Journal articles: 'Lactose hydration'

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Wijayasinghe, Rangani, Todor Vasiljevic, and Jayani Chandrapala. "Lactose behaviour in the presence of lactic acid and calcium." Journal of Dairy Research 83, no. 3 (August 2016): 395–401. http://dx.doi.org/10.1017/s0022029916000315.

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Physical properties of lactose appeared influenced by presence of lactic acid in the system. Some other components such as Ca may further attenuate lactose behaviour and impact its phase transition. A model-based study was thus implemented with varying concentrations of Ca (0·12, 0·072 or 0·035% w/w) and lactic acid (0·05, 0·2, 0·4 or 1% w/w) in establishing the effects of these two main acid whey constituents on lactose phase behaviour. Concentrated solutions (50% w/w) containing lactose, lactic acid and Ca were analysed for thermal behaviour and structural changes by Differential Scanning Colorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. Presence of 1% (w/w) lactic acid and 0·12% (w/w) Ca in lactose solution significantly increased the evaporation enthalpy of water, delayed and increased the energy required for lactose crystallisation as compared to pure lactose. FTIR analysis indicated a strong hydration layer surrounding lactose molecules, restricting water mobility and/or inducing structural changes of lactose, hindering its crystallisation. The formation of calcium lactate, which restricts the diffusion of lactose molecules, is also partly responsible. It appears that Ca removal from acid whey may be a necessary step in improving the processability of acid whey.

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Alvi, Muhammad Adnan, Zhaohui Zhang, Xiaoyan Zhao, Yang Yu, Tianyao Zhang, and Jawad Aslam. "Dissociation and Recombination Processes in Lactose Monohydrate Detected by THz Time-Domain Spectroscopy." Journal of Advanced Computational Intelligence and Intelligent Informatics 26, no. 5 (September 20, 2022): 740–46. http://dx.doi.org/10.20965/jaciii.2022.p0740.

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The terahertz (THz) region has much appeal for differentiating between hydrate systems and for physically characterizing pharmaceutical drug materials. The present study employs THz absorption spectroscopy to investigate the effect of heating on dehydration and hydration in α-lactose monohydrate. Distinctive THz absorption spectra were observed following various heating durations. The THz absorption spectra for α-lactose monohydrate and anhydrous α-lactose exhibit clear differences. Pure α-lactose monohydrate displays clear absorption peaks at 0.53, 1.05, 1.11, 1.33, and 1.56 THz. The complete dehydration of α-lactose monohydrate takes only 15 mins at 145°C (418 K). Moreover, the THz refractive index of α-lactose monohydrate decreases during dehydration. The dehydration of α-lactose monohydrate was also studied using Beer–Lambert law to compare THz absorption spectra as functions of the heating time. The absorption coefficient spectra recorded at 0.53 and 1.35 THz for α-lactose monohydrate after different dehydration times vary linearly with the remaining water content.

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Rohde, Jon E. "Training of Paramedical Personnel. Understanding priorities in treatment of diarrhea." Paediatrica Indonesiana 14, no. 9-10 (June 13, 2017): 153. http://dx.doi.org/10.14238/pi14.9-10.1974.153-8.

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Training of medical personnel must emphasize the importtance of dehydration, its diagnosis, recognition, prevention and treatment. Maintenance of body hydration is the key to therapy for cholera, amoebiasis, toxin producing E. coli, measles, lactose intolerance, acute food poisoning, dengue hemorrhagic fever, viral enteritis, heat stoke; the list is almost endless. Management is basically the same for all.

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Gutierrez, Elizabeth, Jessica Jarick Metcalfe, and Melissa Pflugh Prescott. "The Relationship between Fluid Milk, Water, and 100% Juice and Health Outcomes among Children and Adolescents." Nutrients 14, no. 9 (April 30, 2022): 1892. http://dx.doi.org/10.3390/nu14091892.

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Beverages can provide improved nutrient intake and hydration, but also pose concerns related to overnutrition or contamination for children and adolescents who are in a time of critical growth. This narrative review aims to understand the impact of milk, 100% juice, and water consumption on health-related outcomes in youth. The literature review conducted used PubMed, Web of Science, and CABI global. Forty-five research articles met the quality criteria and were included. Health organization and governmental resources were also reviewed to identify current intake and consumption recommendations. All beverages in this review were associated with a variety of desirable and undesirable findings that spanned over 40 different health outcomes. Most studies that assessed milk lacked clear distinction between milk type (flavored vs. unflavored) or fat percentage, making it difficult to understand the impact of milk consumption. The relationship between milk intake and anthropometric-related outcomes were mixed within and across studies. Water was consistently associated with better hydration, while 100% juice and flavored milk intake was associated with more desirable dietary patterns or nutrients that children are currently not consuming adequate amounts of. The implications of these findings were discussed in the context of the National School Lunch Program (NSLP), while considering the impact of issues such as contaminated water and lactose intolerance. This review suggests that water may be an optimal default beverage option in the NSLP to promote hydration and accommodate beverage preferences for those with lactose intolerance.

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Cal, S., G. Iglesias, C. Souto, A. Concheiro, J. L. Gómez-Amoza, and R. Martinez-Pacheco. "Effects of hydration on the properties of a roller-dried β-lactose for direct compression." International Journal of Pharmaceutics 129, no. 1-2 (March 1996): 253–61. http://dx.doi.org/10.1016/0378-5173(95)04360-8.

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Ting, Valeska P., Marc Schmidtmann, Paul F. Henry, Sandie E. Dann, Jenna L. Crisp, Chick C. Wilson, and Mark T. Weller. "The kinetics of bulk hydration of the disaccharides α-lactose and trehalose by in situ neutron powder diffraction." MedChemComm 1, no. 5 (2010): 345. http://dx.doi.org/10.1039/c0md00093k.

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Kumar, Ashwani, Ruby Rani, Tanu Sharma, and Rajinder K. Bamezai. "Effect of temperature and concentration alterations on the volumetric, acoustic and hydration studies of l-threonine in aqueous lactose solutions." Journal of Molecular Liquids 276 (February 2019): 961–69. http://dx.doi.org/10.1016/j.molliq.2018.12.113.

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Afrassiabian, Zahra, and Khashayar Saleh. "Caking of anhydrous lactose powder owing to phase transition and solid-state hydration under humid conditions: From microscopic to bulk behavior." Powder Technology 363 (March 2020): 488–99. http://dx.doi.org/10.1016/j.powtec.2020.01.033.

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Angberg, M., C. Nystrμ, and S. Castensson. "Evaluation of heat-conduction microcalorimetry in pharmaceutical stability studies. IV. The influence of microcrystalline cellulose on the hydration rate of anhydrous lactose." International Journal of Pharmaceutics 77, no. 2-3 (November 1991): 269–77. http://dx.doi.org/10.1016/0378-5173(91)90327-k.

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Singh, Sudarshan, Tanvi R. Dodiya, Rajesh Dodiya, Sangeeta Singh, and Sunil B. Bothara. "In vivo, ex vivo and in vitro Mucoadhesive Strength Assessment of Potential Pharmaceutical Bio-resource Polymer from Diospyros melonoxylon Roxb seeds." International Journal of Pharmaceutical Sciences and Nanotechnology 14, no. 1 (January 1, 2021): 5307–14. http://dx.doi.org/10.37285/ijpsn.2021.14.1.6.

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In this study, an oral bio-based mucoadhesive polymer was developed from Diospyros melonoxylon Roxb (Ebenaceae) seed mucilage and evaluated for mucoadhesive strength. The mucilage showed shear stress results (0.140 ± 0.0007N), with comparable adhesiveness to HPMC E5 (0.098 ± 0.0008N). Force of adhesion required to detach the seed mucilage and HPMC E5 tablets from the mucin of intestinal tissue were 0.0509 ± 0.0007 (N) and 0.0049 ± 0.0006 (N). Seed mucilage revealed significant higher detachment time, erosion time, in vitro wash off time and ex vivo residence compared to HPMC E5 and lactose tablets (p<0.01). In vivo test indicated that seed mucilage tablets possessed good mucoadhesive strength compared to HPMC E5 and resisted disintegration for ≤ 8 h. The swelling index and wetting time showed comparable results between the mucilage and synthetic polymer tablets. Mucilage demonstrated high moisture absorption, percentage hydration, and matrix erosion of 20.0 ± 0.037, 53.66 ± 0.127, and 20.00 ± 0.077 compared to HPMC E5 10.0 ± 0.079, 36.00 ± 0.089, and 1.26 ± 0.085. The mucoadhesive properties of seeds mucilage were comparable to guar gum and HPMC E5. Thus, seed mucilage of D. melonoxylon can be exploited for usage as pharmaceutical excipient in oral bioadhesive drug delivery systems.

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Giuffrida, Sergio, Antonio Cupane, and Grazia Cottone. "“Water Association” Band in Saccharide Amorphous Matrices: Role of Residual Water on Bioprotection." International Journal of Molecular Sciences 22, no. 5 (March 2, 2021): 2496. http://dx.doi.org/10.3390/ijms22052496.

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Saccharides protect biostructures against adverse environmental conditions mainly by preventing large scale motions leading to unfolding. The efficiency of this molecular mechanism, which is higher in trehalose with respect to other sugars, strongly depends on hydration and sugar/protein ratio. Here we report an Infrared Spectroscopy study on dry amorphous matrices of the disaccharides trehalose, maltose, sucrose and lactose, and the trisaccharide raffinose. Samples with and without embedded protein (Myoglobin) are investigated at different sugar/protein ratios, and compared. To inspect matrix properties we analyse the Water Association Band (WAB), and carefully decompose it into sub-bands, since their relative population has been shown to effectively probe water structure and dynamics in different matrices. In this work the analysis is extended to investigate the structure of protein-sugar-water samples, for the first time. Results show that several classes of water molecules can be identified in the protein and sugar environment and that their relative population is dependent on the type of sugar and, most important, on the sugar/protein ratio. This gives relevant information on how the molecular interplay between residual waters, sugar and protein molecules affect the biopreserving properties of saccharides matrices.

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Singh, Sudarshan, Tanvi R. Dodiya, Sangeeta Singh, Rajesh Dodiya, and Sunil B. Bothara. "Bio-based Polymer Isolated from Seeds of Buchanania lanzan Spreng with Potential Use as Pharmaceutical Mucoadhesive Excipient." International Journal of Pharmaceutical Sciences and Nanotechnology 13, no. 4 (July 12, 2020): 5028–35. http://dx.doi.org/10.37285/ijpsn.2020.13.4.9.

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This study was aimed to develop an oral bio-based mucoadhesive polymer from seeds mucilage of Buchanania lanzan spreng, belongs to family anacardiaceae. Isolated mucilage was evaluated for mucoadhesive strength and compared with existing polymer. The mucilage showed shear stress results (0.099 ± 0.0001N), with comparable adhesiveness to methocel E5 (0.098 ± 0.0008N). Force of adhesion required to detach the seed mucilage and methocel E5 tablets from the mucin of intestinal tissue were 0.0276 ± 0.0019 (N) and 0.0049 ± 0.0006 (N), respectively. Seed mucilage revealed significant (P<0.01) higher detachment time, erosion time, in-vitro wash-off time and ex-vivo residence compared to methocel E5 and lactose tablets. In vivo test indicated that seed mucilage tablets possessed good mucoadhesive strength compared to methocel E5 and resisted disintegration for ≤ 8 h. The swelling index and wetting time showed comparable results between the mucilage and synthetic polymer tablets. Mucilage demonstrated high moisture absorption, percentage hydration, and matrix erosion of 18.57 ± 0.036, 50.00 ± 0.051, and 8.30 ± 0.155 compared to methocel E5 10.0 ± 0.079, 36.00 ± 0.089, and 1.26 ± 0.085, respectively. Mucoadhesive properties of seeds mucilage were comparable to guar gum and methocel E5, thus seed mucilage of B. lanzan can be potentially exploited for usage as a bioadhesive pharmaceutical excipient.

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Choudbua, Noppawan, Thawatchai Phaechamud, and Garnpimol C. Ritthidej. "Development of Prolonged Action, Bioadhesive and Slowly Dissolving Minitablets." Advanced Materials Research 93-94 (January 2010): 425–28. http://dx.doi.org/10.4028/www.scientific.net/amr.93-94.425.

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Minitablets can be used either single or multiple unit sustained release dosage form. The objectives of this study were to prepare and evaluate the prolonged action, bioadhesive and slowly dissolving minitablets. The minitablets (Ø 2.5 mm, 7 mg) were prepared by direct compression method using 75%w/w of various hydrophilic polymers: hydroxypropylcellulose (HPC), hydroxypropyl methylcellulose (HPMC), carboxy methylcellulose (CMC), pectin (PT) and chitosan (CS). Spray dried lactose was used as diluent. Prior to compression, the angle of repose, bulk-tab density and %compressibility of each mixed powder were evaluated. The rate of hydration and erosion of the obtained minitablets were carried out in phosphate buffer (pH 7.4). The powder blends containing HPC, CMC or HPMC showed satisfactory flow properties and compressibility. Accordingly, the prepared matrix tablets of HPC, CMC and HPMC showed good physical properties such as hardness, while those of CS and PT showed poor properties. The degree of swelling were ranked as CS>CMC>PT>HPC>HPMC, while the erosion were ranked as CMC≈HPMC≈PT > HPC≈CS. Adhesion time of these minitablets on isolated pig intestine was >30 min for CMC, PT and CS tablets while HPC and HPMC tablets exhibited weaker bioadhesion. In conclusion, among tested polymers, CS, PT and CMC were appropriate for prolonged action, bioadhesive and slowly dissolving minitablets.

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Yen, Tran Thi Hai, Le Nho Dan, Le Hoang Duc, Bui Thanh Tung, and Pham Thi Minh Hue. "Preparation and Characterization of Freeze-dried Liposomes Loaded with Amphotericin B." Current Drug Therapy 14, no. 1 (March 6, 2019): 65–73. http://dx.doi.org/10.2174/1574885514666181217130259.

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Background: Amphotericin B (AmB) is a drug of choice in the therapy of systemic fungal infection because of its board-spectrum antifungal activity. However, its conventional formulation has many side effects such as acute and chronic nephrotoxicity. Liposomes have been developed to reduce the drug’s toxicity. However, they had to meet strict stability criteria. In general, liposomes can be freeze-dried to inhibit liposomes infusion, phospholipids degradation during storage. Liposomal size usually increases after freeze-drying because of being influenced by many factors in freezing, lyophilizing and rehydration processes. Therefore, cryoprotectants are used to stabilize liposomal vesicles during freeze-drying process. Objective: In the present study, we developed AmB liposomal suspension and lyophilized liposomes loaded with AmB, evaluated the effect of different cryoprotectants on the characterization of freeze-dried AmB liposomes. Methods: In this study, AmB liposomes were prepared from hydrogenated soy phosphatidylcholine, distearoylphosphatidylglycerol and cholesterol by thin lipid film hydration method using different hydrate mediums likely: Glucose solution, citrate buffer, phosphate buffer. High-pressure homogenization and extrusion methods were used to reducing vesicles size. Dynamic light scattering was used to characterize liposomal size, and size distribution. HPLC method was used to assay drug and determine entrapment efficiency. Liposomal suspension was lyophilized with different cryoprotectants: Sucrose, mannitol, lactose, trehalose and glycerol. Differential scanning calorimetry was used to study lyophilized cake. Results: We found that liposomal suspension with hydration medium10 mM citrate buffer pH 5.5 had a small average size (<100nm) and narrow distribution (PDI <0.2). Sucrose and trehalose stabilized vesicles size during freezing process, and lyophilized liposomes with sucrose and trehalose had an elegant appearance, yellow, compact cake. DSC study showed that sucrose and trehalose in lyophilized cake were amorphous. The cake was rehydrated within 10 seconds to form liposomal suspension, in which vesicles size was less than 140 nm. Conclusion: We have developed successfully AmB liposomal suspension and lyophilized liposomes loaded with AmB. Sucrose and trehalose can be used as cryoprotectants in the freeze-drying and reconstitution process.

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Chougule, Mahavir Bhupal, Bijay Kumar Padhi, and Ambikanandan Misra. "Nano-Liposomal Dry Powder Inhaler of Amiloride Hydrochloride." Journal of Nanoscience and Nanotechnology 6, no. 9 (September 1, 2006): 3001–9. http://dx.doi.org/10.1166/jnn.2006.405.

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The purpose of this study was to encapsulate Amiloride Hydrochloride into nano-liposomes, incorporate it into dry powder inhaler, and to provide prolonged effective concentration in airways to enhance mucociliary clearance and prevent secondary infection in cystic fibrosis. Liposomes were prepared by thin film hydration technique and then dispersion was passed through high pressure homogenizer to achieve size of nanometer range. Nano-liposomes were separated by centrifugation and were characterized. They were dispersed in phosphate buffer saline pH 7.4 containing carriers (lactose/sucrose/mannitol), and glycine as anti-adherent. The resultant dispersion was spray dried. The spray dried powders were characterized and in vitro drug release studies were performed using phosphate buffer saline pH 7.4. in vitro and in vivo drug pulmonary deposition was carried out using Andersen Cascade Impactor and by estimating drug in bronchial alveolar lavage and lung homogenate after intratracheal instillation in rats respectively. Nano-liposomes were found to have mean volume diameter of 198 ± 15 nm, and 57% ± 1.9% of drug entrapment. Mannitol based formulation was found to have low density, good flowability, particle size of 6.7 ± 0.6 μm determined by Malvern MasterSizer, maximum fine particle fraction of 67.6 ± 0.6%, mean mass aerodynamic diameter 2.3 ± 0.1 μm, and geometric standard deviation 2.4 ± 0.1. Developed formulations were found to have prolonged drug release following Higuchi's Controlled Release model and in vivo studies showed maximal retention time of drug of 12 hrs within the lungs and slow clearance from the lungs. This study provides a practical approach for direct lung delivery of Amiloride Hydrochloride encapsulated in liposomes for controlled and prolonged retention at the site of action from dry powder inhaler. It can provide a promising alternative to the presently available nebulizers in terms of prolonged pharmacological effect, reducing systemic side effects such as potassium retention due to rapid clearance of the drug from lungs in patients suffering from cystic fibrosis.

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Kosmidis, Ioannis, Stefanos Nikolaidis, Alexandros Chatzis, Kosmas Christoulas, Thomas Metaxas, and Vassilis Mougios. "Reliability of the Urine Lactate Concentration After Alternating-Intensity Interval Exercise." Proceedings 25, no. 1 (August 29, 2019): 1. http://dx.doi.org/10.3390/proceedings2019025001.

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Aim: Our previous studies have shown that the post-exercise urine lactate concentration is a reliable exercise biomarker under controlled post-exercise hydration conditions. However, the reliability of the urine lactate concentration has been examined only after brief maximal exercise. As a result, there is no information about the reliability of this biomarker after prolonged submaximal exercise. Thus, the aim of the present study was to examine the reliability of the urine lactate concentration after interval exercise of alternating intensity under controlled or ad libitum hydration during exercise. Material & Method: Twenty-eight physically active adults (16 men and 12 women) performed three identical 45-min running tests (2 sets of 22.5 min with 3 min rest interval) on the treadmill with alternating speed and inclination at 19–24 °C, spaced three days apart. The participants drank the same amount of water during exercise in two of tests and ad libitum in the other test, in random, counterbalanced order. Blood samples were collected before exercise and 1, 3, as well as 5 min post-exercise. The highest lactate value among the post-exercise samples of each individual was recorded as his/her peak post-exercise value. Urine samples were collected before exercise and 10 as well as 60 min post-exercise and the average value of the post-exercise samples was recorded. Blood and urine lactate were analyzed spectrophotometrically. Results: The peak post-exercise blood lactate concentration was 5.5 1.7 mmol/L (mean SD throughout) for men and 4.7 1.8 mmol/L for women. The post-exercise urine lactate concentration was 1.6 1.0 mmol/L for men and 1.5 1.0 mmol/L for women. The reliability of the blood lactate concentration at the three tests was high (ICC 077–0.88), being higher under controlled hydration. However, the reliability of the urine lactate concentration was low or non-significant (ICC 0.29–0.36). Conclusions: The urine lactate concentration after prolonged submaximal exercise was lower than the corresponding blood lactate concentration and showed unsatisfactory reliability regardless of the hydration pattern during exercise. Thus, it cannot be used as a biomarker for this kind of exercise.

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T. J., Cicily, Sherin Sams, and Anitha K. Gopal. "Effect of hydration therapy on oligohydramnios." International Journal of Reproduction, Contraception, Obstetrics and Gynecology 6, no. 5 (April 27, 2017): 1800. http://dx.doi.org/10.18203/2320-1770.ijrcog20171538.

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Background: Oligamnios is defined as an AFI <5cm, SDP <2cms or an AFI below the 5th centile for the gestational age and is associated with many maternal and perinatal complications. An effective, non-invasive method of increasing AFV is the hydration therapy. The objective of present study was to determine the impact of hydration therapy in patients complicated by oligamnios and to measure the maternal and perinatal outcome in oligamnios corrected by Intravenous hydration therapy.Methods: It is a randomised control trial done at Government Medical College, Kottayam, Kerala, India from Jan 2012 to May 2013. 136 singleton pregnant females with gestation age >34 weeks with AFI <5 cms were randomised into an Intervention group who receive 1 litre of ringer lactate i.v given daily for 5 days and nonintervention group who were kept under observation by serial ultrasound and antepartum fetal surveillance. All were followed-up till delivery to obtain maternal and perinatal outcomes.Results: Among the 68 who were given intervention, 61 responded and 7 were non responders. With hydration therapy, mean increase in AFI was 4 cm and minimum duration needed for improvement was one week. Hydration therapy showed significant improvement in the maternal and fetal outcomes. Intravenous route of maternal hydration has the advantage that a fixed amount of fluid can be infused at a relatively constant rate with ensured compliance.Conclusions: From the study, it was concluded that Hydration therapy is an excellent method to improve AFI in Oligohydramnios and maternal and perinatal outcome.

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Kim, Yuyoung, and Hongkee Sah. "Protein Loading into Spongelike PLGA Microspheres." Pharmaceutics 13, no. 2 (January 21, 2021): 137. http://dx.doi.org/10.3390/pharmaceutics13020137.

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A self-healing microencapsulation process involves mixing preformed porous microspheres in an aqueous solution containing the desired protein and converting them into closed-pore microspheres. Spongelike poly-d,l-lactide-co-glycolide (PLGA) microspheres are expected to be advantageous to protein loading through self-healing. This study aimed to identify and assess relevant critical parameters, using lysozyme as a model protein. Several parameters governed lysozyme loading. The pore characteristics (open-pore, closed-pore, and porosity) of the preformed microspheres substantially affected lysozyme loading efficiency. The type of surfactant present in the aqueous medium also influenced lysozyme loading efficiency. For instance, cetyltrimethylammonium bromide showing a superior wetting functionality increased the extent of lysozyme loading more than twice as compared to Tween 80. Dried preformed microspheres were commonly used before, but our study found that wet microspheres obtained at the end of the microsphere manufacturing process displayed significant advantages in lysozyme loading. Not only could an incubation time for hydrating the microspheres be shortened dramatically, but also a much more considerable amount of lysozyme was encapsulated. Interestingly, the degree of microsphere hydration determined the microstructure and morphology of closed-pore microspheres after self-healing. Understanding these critical process parameters would help tailor protein loading into spongelike PLGA microspheres in a bespoke manner.

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D’Souza, Susan, Rossella Dorati, and Patrick P. DeLuca. "Effect of Hydration on Physicochemical Properties of End-Capped PLGA." Advances in Biomaterials 2014 (August 13, 2014): 1–9. http://dx.doi.org/10.1155/2014/834942.

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The objective of this study was to assess the physicochemical effects of hydrating a hydrophobic end-capped poly(lactide-co-glycolide) (PLGA) polymer in the liquid and vapor state. PLGA RG503 polymer was incubated at 37°C in 0.5% polyvinyl alcohol (PVA) solution and at 90% RH. Samples were withdrawn at predetermined intervals and changes to polymer properties like glass transition temperature (Tg), moisture uptake, molecular weight change, and % acid number were determined using differential scanning calorimetry, Karl Fisher titrimetry, gel permeation chromatography, and acid base titrimetry, respectively. Study results showed that Tg was depressed instantaneously upon hydration, indicating that bulk water acted as a plasticizer of hydrophobic end-capped PLGA. Tg values decreased to levels below the incubation temperature when hydrated in 0.5% PVA solution but not in 90% RH. The drop in Tg exhibited a linear relationship (R2>0.99) to the amount of water uptake by the polymer; higher moisture uptake was noted with liquid water. Removal of moisture from the polymer matrix resulted in recovery of Tg, only up to a period of 14 days. Presence of water in liquid or vapor form caused a reduction in molecular weight of the polymer and a corresponding increase in % acid number over the duration of the study.

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Kondoh, A., and T. Oi. "Interaction of Alkaline Earth Metal Ions with Acetic and Lactic Acid in Aqueous Solutions Studied by 13C NMR Spectroscopy." Zeitschrift für Naturforschung A 52, no. 4 (April 1, 1997): 351–57. http://dx.doi.org/10.1515/zna-1997-0410.

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Abstract Interaction of alkaline earth metal (magnesium, calcium, strontium and barium) ions with acetic and lactic acid in aqueous media was investigated by 13C NMR spectroscopy. In the acetate systems, signals whose chemical shifts were the averages of those of the free and bound acetate ions were observed. Downfield shifts of the carboxylate carbon signals with increasing metal ion concentration indicated that the acetate ion acted as a monodentate ligand coordinating to the metal ion using the carboxylate group. The metal ion concentration dependence of the peak positions of the methine and carboxylate carbon signals of the lactate ion in the lactate systems suggested that the lactate ion coordinated to a metal ion using the carboxylate and hydroxyl groups. Unique upfield shifts upon complexation in the magnesium lactate systems suggested that the lactate ion coordinated to the magnesium ion from outside the primary hydration sphere.The present results were consistent with the isotope effects of the alkaline earth metals observed in cation exchange chromatography.

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de Jesus Silva, Raquel, Lysandro Pinto Borges, Lucindo José Quintans-Júnior, Camila Ferezin Resende, Flávio Adsuara Cadegiani, João Henrique Gomes, and Renata Rebello Mendes. "Acute effects of a typical rhythmic gymnastic training session on physiological parameters in Olympic athletes." Kinesiology 54, no. 2 (2022): 278–87. http://dx.doi.org/10.26582/k.54.2.9.

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The aim of this study was to evaluate the effects of a day with two separate training sessions (morning and afternoon) of rhythmic gymnastics on erythrocytes, leukocytes, muscle damage, oxidative stress, and hydration of Brazilian team [age 17.7 (±1.1) years; body height 165 (±0.5) cm; body mass 49.7 (±4.2) kg]. Heart rate and session-ratings of perceived exertion were used to monitor training intensity. Blood samples were collected immediately before (M1) and after (M2) the training day for analyzing erythrocytes, leukocytes, plasma creatine kinase activity, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, ferric reducing ability plasma, thyroid-stimulating hormone, and free T4. Saliva was collected for cortisol analysis. After 24 hours rest (M3), blood collection was performed to analyze creatine kinase and lactate dehydrogenase. The moderate-intensity training day induced significant elevations of total leukocytes (5,163.3 to 9,617.8), lymphocytes (1,752.7 to 2,729.7), neutrophils (2,873.9 to 6,163.6), monocytes (255.7 to 519.1), platelets (280,000.0 to 300,666.7), aspartate aminotransferase (13.1 to 25.6), lactate dehydrogenase (102.5 to 249.1), thyroid-stimulating hormone (1.0 to 3.2), and ferric reducing ability plasma (136.8 to 165.4), as well as significant reductions in red cells (4,691,111.1 to 4,497,777.8), hematocrit (42.1 to 39.3), and hemoglobin (12.9 to 12.5) at M2. There were also significant increases in creatine kinase (144.2 to 519.3) and lactate dehydrogenase (102.5 to 538.2) at M3. The average dehydration rate was 1.3%. A moderate-intensity day of training in rhythmic gymnastics of 8h21min duration caused hemolysis, leukocytosis, muscle damage, redox status perturbations, and insufficient hydration status. These findings show that athletes are exposed to physiological vulnerabilities that can possibly harm their performance and health.

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Judelson, Daniel A., Carl M. Maresh, Linda M. Yamamoto, Mark J. Farrell, Lawrence E. Armstrong, William J. Kraemer, Jeff S. Volek, Barry A. Spiering, Douglas J. Casa, and Jeffrey M. Anderson. "Effect of hydration state on resistance exercise-induced endocrine markers of anabolism, catabolism, and metabolism." Journal of Applied Physiology 105, no. 3 (September 2008): 816–24. http://dx.doi.org/10.1152/japplphysiol.01010.2007.

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Hypohydration (decreased total body water) exacerbates the catabolic hormonal response to endurance exercise with unclear effects on anabolic hormones. Limited research exists that evaluates the effect of hypohydration on endocrine responses to resistance exercise; this work merits attention as the acute postexercise hormonal environment potently modulates resistance training adaptations. The purpose of this study was to examine the effect of hydration state on the endocrine and metabolic responses to resistance exercise. Seven healthy resistance-trained men (age = 23 ± 4 yr, body mass = 87.8 ± 6.8 kg, body fat = 11.5 ± 5.2%) completed three identical resistance exercise bouts in different hydration states: euhydrated (EU), hypohydrated by ∼2.5% body mass (HY25), and hypohydrated by ∼5.0% body mass (HY50). Investigators manipulated hydration status via controlled water deprivation and exercise-heat stress. Cortisol, epinephrine, norepinephrine, testosterone, growth hormone, insulin-like growth factor-I, insulin, glucose, lactate, glycerol, and free fatty acids were measured during euhydrated rest, immediately preceding resistance exercise, immediately postexercise, and during 60 min of recovery. Body mass decreased 0.2 ± 0.4, 2.4 ± 0.4, and 4.8 ± 0.4% during EU, HY25, and HY50, respectively, supported by humoral and urinary changes that clearly indicated subjects achieved three distinct hydration states. Hypohydration significantly 1) increased circulating concentrations of cortisol and norepinephrine, 2) attenuated the testosterone response to exercise, and 3) altered carbohydrate and lipid metabolism. These results suggest that hypohydration can modify the hormonal and metabolic response to resistance exercise, influencing the postexercise circulatory milieu.

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Wing-Gaia, Stacie L., Andrew W. Subudhi, and Eldon W. Askew. "Effects of Purified Oxygenated Water on Exercise Performance during Acute Hypoxic Exposure." International Journal of Sport Nutrition and Exercise Metabolism 15, no. 6 (December 2005): 680–88. http://dx.doi.org/10.1123/ijsnem.15.6.680.

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The purpose of this study was to assess the effects of purified oxygenated water on exercise performance under hypoxic conditions. Nine recreational male cyclists (age = 26.6 ± 5.2 y, weight = 87.6 ± 19.5 kg, VO2peak = 46.5 ± 5.9 mL · kg−1 · min−1) completed two 600 kJ cycling time trials under hypoxic conditions (FIO2 = 13.6% O2, Pbar = 641 mmHg) separated by 2 wk. Trials were completed following 3 d ingestion of 35 mL · kg−1 · d−1 of control (CON) or experimental (EXP) water. Time to completion, heart rate (HR), rate of perceived exertion (RPE), pulse oximetry (SaO2), blood gases (PcO2 and PcCO2), and lactate were measured during the trials. Hydration was assessed with pre- and post-exercise body weight and 24-h urine specific gravity. Performance, hydration, and blood oxygenation were unaffected by EXP water. Results of this study suggest that purified oxygenated water does not improve exercise performance in moderately active males.

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Sakata, Yukoh, Sumihiro Shiraishi, and Makoto Otsuka. "Characterization of dehydration and hydration behavior of calcium lactate pentahydrate and its anhydrate." Colloids and Surfaces B: Biointerfaces 46, no. 3 (December 2005): 135–41. http://dx.doi.org/10.1016/j.colsurfb.2005.10.004.

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Chycki, Jakub, Maciej Kostrzewa, Adam Maszczyk, and Adam Zajac. "Chronic Ingestion of Bicarbonate-Rich Water Improves Anaerobic Performance in Hypohydrated Elite Judo Athletes: A Pilot Study." International Journal of Environmental Research and Public Health 18, no. 9 (May 6, 2021): 4948. http://dx.doi.org/10.3390/ijerph18094948.

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In combat sports, anaerobic power and anaerobic capacity determine sport performance and the dominant metabolic pathways. The decline in performance during exercise that is attributed to the cumulative effects of fatigue, including excessive accumulation of metabolites, depletion of energy substrates, and water and electrolyte disturbances, seems to be of greatest significance. In our experiment, we evaluated the effectiveness of three weeks of bicarbonate-rich water ingestion on anaerobic performance in a state of hydration and dehydration in elite judo athletes. Eight male, elite judo athletes participated in two single-blind, repeated-measures trials. They were assigned to two hydration protocols, ingesting low mineralized table water and bicarbonate-rich water. Anaerobic performance was evaluated by two 30 s Wingate tests for lower and upper limbs, respectively, under conditions of hydration as well as exercise-induced dehydration. Resting, post-ingestion, and post-exercise concentrations of bicarbonate (HCO3), urine osmolality (UOSM), urine specific gravity (UGRAV), and lactate (La) were measured. The current investigation assessed two related factors that impair anaerobic performance—hypohydration and buffering capacity. High-bicarbonate water ingestion improved buffering capacity, and we demonstrated the potential role of this mechanism and its phenomenon in masking the adverse effects of dehydration in the context of repeated high-intensity anaerobic exercise (HIAE).

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Xie, Yao, Jia Liu, Shu Cai, Xiaogang Bao, Qianqian Li, and Guohua Xu. "Setting Characteristics and High Compressive Strength of an Anti-washout, Injectable Calcium Phosphate Cement Combined with Thermosensitive Hydrogel." Materials 13, no. 24 (December 17, 2020): 5779. http://dx.doi.org/10.3390/ma13245779.

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In this work, a thermosensitive poly(D,L-lactide-co-glycolide)-poly(ethylene glycol)-poly(D,L-lactide-co-glycolide) (PLGA-PEG-PLGA) hydrogel was introduced into calcium phosphate cement (CPC) to enhance the anti-washout property of CPC. The effects of the hydrogel on the setting time, injectability, anti-washout property and compressive strength of CPC were thoroughly investigated. The results showed that the hydrogel significantly increased the injectability and anti-washout property of CPC, meanwhile maintained the setting time with an acceptable range. Moreover, the hydrogel improved the initial compressive strength of CPC. The composite cement with 20% v/v hydrogel in the liquid phase showed fine crystals of hydration product, a more compact microstructure and lower porosity compared with control CPC. The analysis of X-ray diffraction (XRD), infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) indicated that suitable volume ratio of hydrogel (20% v/v) in the setting liquid of CPC could promote the formation of hydroxyapatite in the early hydration period. The degradation behavior of the cement was characterized by immersion tests in simulated body fluid. The hydrogel had no adverse effect on the degradation rate of CPC over the immersion period of 23 days. This study indicated that incorporating PLGA-PEG-PLGA hydrogel could be a promising strategy to reinforce the handing properties and initial compressive strength of calcium phosphate cement.

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Esposito, A., A. Lukas, J. E. Meany, and Y. Pocker. "The reversible enolization and hydration of pyruvate: possible roles of keto, enol, and hydrated pyruvate in lactate dehydrogenase catalysis." Canadian Journal of Chemistry 77, no. 5-6 (June 1, 1999): 1108–17. http://dx.doi.org/10.1139/v99-071.

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The reversible enolization and hydration of pyruvic acid and pyruvate anion were monitored using spectrophotometric methods at several temperatures. Widely varying values for the equilibrium constant for the enolization of pyruvic acid and pyruvate ion appear in the literature. To accurately determine the position of equilibrium for the enolization reaction, we have developed a method that gives consistent results in which purified samples of sodium pyruvate are first "titrated" with triiodide ion to remove any triiodide-scavenging impurities such as those resulting from aldol condensation reactions. After reequilibration to allow the regeneration of enol pyruvate, the addition of small quantities of triiodide result in an initial burst in the decrease of absorbance at 353 nm, followed by the much slower zero-order decrease due to the formation of new enol pyvuvate molecules. The absorbance change during the burst phase of the reaction is proportional to the enol concentration plus that of any triiodide-scavenging impurity which may be present in the original pyruvate solution. Thus, as the quantity of triiodide used in the pretreatment stage of the experiments is increased, these burst absorbance changes, ΔA, decrease until a constant value of ΔA is reached. Accordingly, this final ΔA value is proportional to enol pyruvate (or enol pyruvic acid) in the absence of triiodide-scavenging impurity, allowing the accurate and reproducible determinations of Kenol. The equilibrium constants for both pyruvate and pyruvic acid are relatively temperature insensitive and, typically, Kenol (pyruvate anion) = 2.6 × 10-5 and Kenol (pyruvic acid) = 7.8 × 10-5 at 25.0°C. The zero-order phase of the reaction of triiodide ion may be used to calculate rate constants for enolization. The hydration and dehydration of pyruvic acid were followed directly by following absorbance changes in the peak at 340 nm due to the keto group. The thermodynamic and kinetic results reported in this paper are used to help determine whether the observed "substrate" inhibition of the lactate dehydrogenase catalyzed reduction of pyruvate is actually caused by keto, hydrated, or enol pyruvate.Key words: pyruvate, enolization, hydration, lactate dehydrogenase.

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Fini, D. S., V. C. Miguel, V. S. Pinto, V. C. Pandolfelli, M. H. Moreira, and A. P. Luz. "Aluminum lactate role in improving hydration and drying behavior of MgO-bonded refractory castables." Ceramics International 46, no. 10 (July 2020): 17093–102. http://dx.doi.org/10.1016/j.ceramint.2020.04.006.

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Li, Shimin, Edward Kim, and Joseph A. Bonanno. "Fluid transport by the cornea endothelium is dependent on buffering lactic acid efflux." American Journal of Physiology-Cell Physiology 311, no. 1 (July 1, 2016): C116—C126. http://dx.doi.org/10.1152/ajpcell.00095.2016.

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Maintenance of corneal hydration is dependent on the active transport properties of the corneal endothelium. We tested the hypothesis that lactic acid efflux, facilitated by buffering, is a component of the endothelial fluid pump. Rabbit corneas were perfused with bicarbonate-rich (BR) or bicarbonate-free (BF) Ringer of varying buffering power, while corneal thickness was measured. Perfusate was collected and analyzed for lactate efflux. In BF with no added HEPES, the maximal corneal swelling rate was 30.0 ± 4.1 μm/h compared with 5.2 ± 0.9 μm/h in BR. Corneal swelling decreased directly with [HEPES], such that with 60 mM HEPES corneas swelled at 7.5 ± 1.6 μm/h. Perfusate [lactate] increased directly with [HEPES]. Similarly, reducing the [HCO3−] increased corneal swelling and decreased lactate efflux. Corneal swelling was inversely related to Ringer buffering power (β), whereas lactate efflux was directly related to β. Ouabain (100 μM) produced maximal swelling and reduction in lactate efflux, whereas carbonic anhydrase inhibition and an monocarboxylic acid transporter 1 inhibitor produced intermediate swelling and decreases in lactate efflux. Conversely, 10 μM adenosine reduced the swelling rate to 4.2 ± 0.8 μm/h and increased lactate efflux by 25%. We found a strong inverse relation between corneal swelling and lactate efflux ( r = 0.98, P < 0.0001). Introducing lactate in the Ringer transiently increased corneal thickness, reaching a steady state (0 ± 0.6 μm/h) within 90 min. We conclude that corneal endothelial function does not have an absolute requirement for bicarbonate; rather it requires a perfusing solution with high buffering power. This facilitates lactic acid efflux, which is directly linked to water efflux, indicating that lactate flux is a component of the corneal endothelial pump.

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Güvenç, Alpay. "Effects of Ramadan Fasting on Body Composition, Aerobic Performance and Lactate, Heart Rate and Perceptual Responses in Young Soccer Players." Journal of Human Kinetics 29, no. 1 (September 1, 2011): 79–91. http://dx.doi.org/10.2478/v10078-011-0042-9.

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Effects of Ramadan Fasting on Body Composition, Aerobic Performance and Lactate, Heart Rate and Perceptual Responses in Young Soccer PlayersThe purpose of this study was to examine the effects of Ramadan fasting on body composition, aerobic exercise performance and blood lactate, heart rate and perceived exertion in regularly trained young soccer players. Sixteen male soccer players participated in this study. Mean age, stature, body mass and training age of the players were 17.4±1.2 years, 175.4±3.6 cm, 69.6±4.3 kg and 5.1±1.3 years, respectively. During the Ramadan period, all subjects voluntarily chose to follow the fasting guidelines and abstained from eating and drinking from sunrise to sunset. Body composition, hydration status, dietary intake and sleep duration were assessed on four occasions: before Ramadan, at the beginning of Ramadan, at the end of Ramadan and 2 weeks after the end of Ramadan. On each occasion, aerobic exercise performance and blood lactate, heart rate and rating of perceived exertion responses of players were also determined during an incremental running test. Repeated measures of ANOVA revealed that body mass, percentage of body fat, fat-free mass, hydration status, daily sleeping time and daily energy and macronutrient intake of players did not vary significantly throughout the study period (p>0.05). However, players experienced a small but significant decrease in skinfold thicknesses over the course of the study (p<0.05). Although ratings of perceived exertion at submaximal workloads increased during Ramadan (p<0.05), blood lactate and heart rate responses had decreased by the end of Ramadan (p<0.05). In line with these changes, peak running performance and running velocity at anaerobic threshold also improved by the end of Ramadan (p<0.05). Improvements in aerobic exercise performance with time were probably due to the effects of pre-season training program that was performed after the break of the fast (Iftar) during the month of Ramadan. The results of the present study suggest that if regular training regimen, body fluid balance, daily energy intake and sleep duration are maintained as before Ramadan, Ramadan fasting does not have detrimental effects on aerobic exercise performance or body composition in young soccer players.

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Dandia, Anshu, Pratibha Saini, M. J. Chithra, Sivaranjana Reddy Vennapusa, and Vijay Parewa. "Catalyst- and acid-free Markovnikov hydration of alkynes in a sustainable H2O/ethyl lactate system." Journal of Molecular Liquids 331 (June 2021): 115758. http://dx.doi.org/10.1016/j.molliq.2021.115758.

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Gloor, M., J. Fluhr, L. Lehmann, W. Gehring, and R. Thieroff-Ekerdt. "Do Urea/Ammonium Lactate Combinations Achieve Better Skin Protection and Hydration than Either Component Alone?" Skin Pharmacology and Physiology 15, no. 1 (December 21, 2001): 35–43. http://dx.doi.org/10.1159/000049387.

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Tóth, Pál, and Áron Németh. "Investigations into the Usage of the Mineral Alginite Fermented with Lactobacillus Paracasei for Cosmetic Purposes." Hungarian Journal of Industry and Chemistry 50, no. 2 (November 28, 2022): 17–21. http://dx.doi.org/10.33927/hjic-2022-13.

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A remarkable interplay between the skin and the fermentation of lactic acid bacteria (LAB) occurs. The lactate and amino acids in the supernatant of this bacteria help to hydrate the skin. The fermentation broth of lactic acid bacteria, generally referred as "lactic acid bacteria ferment" according to International Nomenclature of Cosmetic Ingredients (INCI), has been used to make a variety of cosmetic components. The goal of this study was to evaluate new approaches to assess ferment filtrates (also known as cell-free fermentation broths) that could be used in cosmeceuticals. Despite years of research on the production of lactic acid, aesthetic evaluations have not yet been performed. First, the Lactobacillus paracasei strain NCAIM B.01525 was employed in our research. Furthermore, a fermentation broth was produced containing the Hungaricum mineral alginite and the impact of hydration on human skin tested. The influence of alginite on the fermentation of LAB was also examined. According to the results of the trials, although alginite might double and triple biomass and specific growth rates, respectively, it cannot facilitate hydration of the skin. These results might contribute to the development of more widely accessible, environmentally-friendly cosmetic components in the future.

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CODINĂ, Georgiana Gabriela, Dumitru ZAHARIA, Silvia MIRONEASA, and Sorina ROPCIUC. "Evaluation of Wheat Flour Dough Rheological Properties by Magnesium Lactate Salt Addition." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Food Science and Technology 75, no. 1 (May 17, 2018): 21. http://dx.doi.org/10.15835/buasvmcn-fst:0019.

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The aim of this study was to assess the influence of the magnesium ions from lactate salt at the level of 100, 150 and 200 mg/100g addition on the rheological properties of the wheat flour dough of 550 type. For this purpose, the empirical dough rheological properties were investigated during mixing, pasting and fermentation process by using the Farinograph, Falling Number, Amylograph and Rheofermentometer devices. During mixing dough hydration capacity decreases with the increased level of magnesium ions addition whereas the dough stability and dough development time decreases at low levels of magnesium ions addition and increases at high levels. The temperature at peak viscosity, total CO2 volume production and the total volume of CO2 lost decreases with the increased level of magnesium addition. PCA analysis shows that the wheat flour with 100 mg and 150 mg /100g magnesium ions addition presents a similar behaviour slightly different to those with 200 mg /100g magnesium ions addition (P < 0.05).

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Kostjukov, Victor V. "Theoretical analysis of lactone and carboxylate forms of camptothecin in aqueous solution: Electronic states, absorption spectra, and hydration." Journal of Molecular Liquids 344 (December 2021): 117804. http://dx.doi.org/10.1016/j.molliq.2021.117804.

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Brancaccio, P. "Influence of Acqua Lete® (Bicarbonate Calcic Natural Mineral Water) Hydration on Blood Lactate After Exercise." Open Sports Medicine Journal 5, no. 1 (February 24, 2012): 1–7. http://dx.doi.org/10.2174/1874387001206010001.

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Kupcis, Peter D., Gary J. Slater, Cathryn L. Pruscino, and Justin G. Kemp. "Influence of Sodium Bicarbonate on Performance and Hydration in Lightweight Rowing." International Journal of Sports Physiology and Performance 7, no. 1 (March 2012): 11–18. http://dx.doi.org/10.1123/ijspp.7.1.11.

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Purpose:The effect of sodium bicarbonate (NaHCO3) ingestion on prerace hydration status and on 2000 m ergometer performance in elite lightweight rowers was examined using a randomized, cross-over, double-blinded design.Methods:To simulate body mass (BM) management strategies common to lightweight rowing, oarsmen reduced BM by approx. 4% in the 24 h preceding the trials, and, in the 2 h before performance, undertook nutritional recovery consisting of mean 43.2 kJ/kg, 2.2 g of CHO per kilogram, 31.8 mg of Na+per kilogram, 24.3 mL of H2O per kilogram, and NaHCO3(0.3 g of NaHCO3per kilogram BM) or placebo (PL; 0.15 g of corn flour per kilogram BM) at 70 to 90 min before racing.Results:At 25 min before performance, NaHCO3had increased blood pH (7.48 ± 0.02 vs PL: 7.41 ± 0.03,P= .005) and bicarbonate concentrations (29.1 ± 1.8 vs PL: 23.9 ± 1.6 mmol/L,P< .001), whereas BM, urine specific gravity, and plasma volume changes were similar between trials. Rowing ergometer times were similar between trials (NaHCO3: 397.8 ± 12.6; PL: 398.6 ± 13.8 s,P= .417), whereas posttest bicarbonate (11.6 ± 2.3 vs 9.4 ± 1.8 mmol/L,P= .003) and lactate concentration increases (13.4 ± 1.7 vs 11.9 ± 1.9 mmol/L,P= .001) were greater with NaHCO3.Conclusion:Sodium bicarbonate did not further enhance rehydration or performance in lightweight rowers when undertaking recommended post-weigh-in nutritional recovery strategies.

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Gomes, Cláudio L. N., Andressa M. Alves, José D. Ribeiro Filho, Felipe J. Moraes Júnior, Raimundo A. Barreto Júnior, Rodrigo S. Fucuta, Bruna M. Ribeiro, and Leandro M. Miranda. "Physiological and biochemical responses and hydration status in equines after two barrel racing courses." Pesquisa Veterinária Brasileira 40, no. 12 (December 2020): 992–1001. http://dx.doi.org/10.1590/1678-5150-pvb-6710.

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ABSTRACT: Studies on biochemical constituents and hydration of horses in training or competitions are essential for the knowledge of their adaptive physiological and metabolic responses to the type of exercise inherent to the sport. The present research evaluated the effects of exercise on hydric status and physiologic and biochemical profiles in Quarter Horses during a barrel race training session. The design consisted of three evaluation times (T): at rest, before the start of physical activity (T0); immediately after a 10-minute warm-up trot and then running the barrel race courses twice with a 10-minute interval (T1); and after one hour’s rest after the second course (T2). The parameters analyzed were: heart rate (HR), respiratory rate (RR), body temperature (BT) and mucose color; the capillary refill time (CRT), packed cell volume (PCV), total plasma proteins (TPP), serum creatinine (CRE) and blood urea nitrogen (BUN) were evaluated and used to infer water status; plasma osmolarity (Osm) was measured; the electrolytes sodium (Na), potassium (K), chloride (Cl), total calcium (tCa), total magnesium (tMg) and phosphorus (P), plasma glucose (Glu) and lactate (Lac) and the muscle enzymes creattine kinase (CK) and aspartate aminotransferase (AST) completed the evaluated parameters. The data for the variables studied were submitted to ANOVA and the Tukey test at 5% probability. After exercise (in T1), HR, RR, BT, PCV, TPP, Glu, Lac, Cre increased (P<0.05), there was also increase in phosphorus and decrease in K (P<0.05), but there was no hypophosphatemia and hipokalemia, respectively. After rest (in T2), only glucose returned to baseline levels (T0) and, with lower mean values, HR, RR, BT, PCV, K and Lac did not return to baseline levels (T0), while P decreased (P<0.05). Osm, BUN, Na, Cl, tCa, tMg, CK and AST did not change between times (P>0.05). It was concluded that the maximum intensity exercise performed on two barrel race courses caused mild hemoconcentration, did not changed plasma osmolality or concentrations of important electrolytes and muscle enzymes of horses, but caused hyperlactatemia without the plasma lactate concentrations being fully recomposed after resting.

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Ceylan, Bayram, Latif Aydos, and Jožef Šimenko. "Effect of Rapid Weight Loss on Hydration Status and Performance in Elite Judo Athletes." Biology 11, no. 4 (March 24, 2022): 500. http://dx.doi.org/10.3390/biology11040500.

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Background: This study aimed to investigate the effect of 5% rapid weight loss on hydration status and judo performance in highly trained judo athletes. Methods: Eighteen male judo athletes participated in the study and were divided into two groups: control and rapid weight loss (RWL). RWL athletes were given 48 h to cut 5% of their body mass while the control group followed their routines. Athletes performed three measurements, including hydration, body mass and three consecutive special judo fitness tests (SJFTs). At the 1st and 6th minutes following each SJFT and 1st, 6th and 15th minutes following the last SJFT, blood lactate and heart rate (HR) was monitored. Results: The effect of RWL on variables was tested with split-plot ANOVA. RWL significantly affected urine specific gravity with a higher value following weight loss compared to baseline and recovery (F2-32 = 13.2, p < 0.001). In addition, athletes’ SJFT total throw numbers differed among measurements (F2-32 = 7.70, p < 0.001). Athletes presented worse SJFT index after weight loss (F2-32 = 8.05, p = 0.01; F1-16 = 6.43, p = 0.02, respectively). HR changed significantly among measurements days and times (F28-448 = 143.10, p < 0.001). Conclusion: RWL induced dehydration and impaired heart rate recovery in highly trained judo athletes, and they could not rehydrate between competition simulated weigh-in and 15 h of recovery.

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Aragón-Vela, Jerónimo, Olivia González-Acevedo, Julio Plaza-Diaz, Rafael A. Casuso, and Jesús R. Huertas. "Physiological Benefits and Performance of Sea Water Ingestion for Athletes in Endurance Events: A Systematic Review." Nutrients 14, no. 21 (November 2, 2022): 4609. http://dx.doi.org/10.3390/nu14214609.

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In different endurance events, athletes have limited access to fluid intake, such as ultra-endurance running. For this reason, it is necessary to establish an adequate hydration strategy for this type of long-duration sporting event. Indeed, it seems that the intake of seawater is a suitable hydration alternative to improve post-exercise recovery in this type of endurance event. This seawater is characterized by being a deep natural mineral water of moderate mineralization, which is usually extracted from a depth of about 700 m. Therefore, the aim of this systematic review is to evaluate the efficacy of seawater consumption in both performance and post-exercise recovery in long-duration sport events. A systematic and comprehensive literature search was performed in PubMed, Scopus, and Web of Science in September 2022. Initially, 8 out of 558 articles met the inclusion criteria. Among these eight studies, six were randomized clinical trials, and two were observational studies (one cross-sectional and one prospective study in well-conditioned student athletes). The results showed that deep sea water consumption accelerated the recovery of aerobic capacity and leg muscle capacity on running performance. In addition, the lactate production after the running exercise in seawater was significantly lower than in pure water. In conclusion, the present review demonstrates that seawater consumption could significantly improve the capacity of recovery after exercise.

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Boulay, Marcel R., Olivier Serresse, Germain Thériault, Jean-Aimé Simoneau, Claude Bouchard, and Thomas M. K. Song. "Changes in Plasma Electrolytes and Muscle Substrates During Short-Term Maximal Exercise in Humans." Canadian Journal of Applied Physiology 20, no. 1 (March 1, 1995): 89–101. http://dx.doi.org/10.1139/h95-007.

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This study compared the effects of 3 short-term maximal exercise tests lasting 10, 30, and 90 sec upon blood volume, plasma electrolytes, glucose, glycerol, lactate and skeletal muscle ATP, PC, glycogen, and lactate concentrations. Seven sedentary male subjects were recruited and 5 of them were randomly assigned to each of the 3 protocols. The tests were performed on a modified ergocycle at workloads of 0.9, 0.075, and 0.05 kp∙kg−1 body mass, respectively. Muscle biopsies were taken from the vastus lateralis before and immediately after each exercise. Venous blood samples were collected before, immediately after, and during the recovery (5, 20, 60, and 120 min). Plasma volume decreased during the 30- and 90-sec tests and was increased in all tests after 60 min of recovery. Plasma K+ increased during all tests and returned to normal values 5 min postexercise, except after the 90-sec test where it fell below resting values. Plasma Na+ and Cl− were unaffected. Blood lactate increased in all tests, glucose increased after the 90-sec test, and glycerol increased after the 30- and 90-sec tests. All 3 tests brought relatively similar changes in muscle ATP, PC, and glycogen while muscle lactate changes were related to exercise duration. These results suggest that a normal hydration status is important for a subject undergoing short training bouts, and that high-intensity tests of short duration do not require a special nutritional regimen to enhance glycogen reserves. Key words: skeletal muscle, hemoconcentration, hypervolemia, hyperkalemia

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MILLER, KIRK, GARY C. PACKARD, and MARY J. PACKARD. "Hydric Conditions During Incubation Influence Locomotor Performance of Hatchling Snapping Turtles." Journal of Experimental Biology 127, no. 1 (January 1, 1987): 401–12. http://dx.doi.org/10.1242/jeb.127.1.401.

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Locomotor performance of hatchling snapping turtles (Chelydra serpentina) was assessed while turtles were running on land and swimming in water. Hatchlings from eggs incubated on a relatively wet substrate were faster than hatchlings from eggs incubated on a drier medium, both in absolute distance and in body lengths moved per unit time. The superior performance of turtles from the wet substrate was not due to differences in hydration of tissues, because differences in performance persisted after turtles from both groups had been fully hydrated. The superior performance of turtles from the wet substrate may stem from a greater aerobic capacity, because these animals accumulated lactate more slowly during locomotion than did turtles from eggs incubated on the dry substrate. These observations may provide a physiological basis for the improved survival of larger hatchlings of many species of reptiles.

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Schwantes, Rebecca H., Sophia M. Charan, Kelvin H. Bates, Yuanlong Huang, Tran B. Nguyen, Huajun Mai, Weimeng Kong, Richard C. Flagan, and John H. Seinfeld. "Low-volatility compounds contribute significantly to isoprene secondary organic aerosol (SOA) under high-NOx conditions." Atmospheric Chemistry and Physics 19, no. 11 (June 3, 2019): 7255–78. http://dx.doi.org/10.5194/acp-19-7255-2019.

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Abstract. Recent advances in our knowledge of the gas-phase oxidation of isoprene, the impact of chamber walls on secondary organic aerosol (SOA) mass yields, and aerosol measurement analysis techniques warrant reevaluating SOA yields from isoprene. In particular, SOA from isoprene oxidation under high-NOx conditions forms via two major pathways: (1) low-volatility nitrates and dinitrates (LV pathway) and (2) hydroxymethyl-methyl-α-lactone (HMML) reaction on a surface or the condensed phase of particles to form 2-methyl glyceric acid and its oligomers (2MGA pathway). These SOA production pathways respond differently to reaction conditions. Past chamber experiments generated SOA with varying contributions from these two unique pathways, leading to results that are difficult to interpret. This study examines the SOA yields from these two pathways independently, which improves the interpretation of previous results and provides further understanding of the relevance of chamber SOA yields to the atmosphere and regional or global modeling. Results suggest that low-volatility nitrates and dinitrates produce significantly more aerosol than previously thought; the experimentally measured SOA mass yield from the LV pathway is ∼0.15. Sufficient seed surface area at the start of the reaction is needed to limit the effects of vapor wall losses of low-volatility compounds and accurately measure the complete SOA mass yield. Under dry conditions, substantial amounts of SOA are formed from HMML ring-opening reactions with inorganic ions and HMML organic oligomerization processes. However, the lactone organic oligomerization reactions are suppressed under more atmospherically relevant humidity levels, where hydration of the lactone is more competitive. This limits the SOA formation potential from the 2MGA pathway to HMML ring-opening reactions with water or inorganic ions under typical atmospheric conditions. The isoprene SOA mass yield from the LV pathway measured in this work is significantly higher than previous studies have reported, suggesting that low-volatility compounds such as organic nitrates and dinitrates may contribute to isoprene SOA under high-NOx conditions significantly more than previously thought and thus deserve continued study.

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Siddiqui, Ayesha, Ayisha Aman, Syeda Areej Fatima, Aliya Riaz, Rashida Rahmat Zohra, and Suad Naheed. "In vitro Studies of the Utilization of Industrially Important Substrates by Lactobacillus sp. AAF-1 Isolated from Coconut Water." Biological Sciences - PJSIR 65, no. 1 (February 24, 2022): 62–66. http://dx.doi.org/10.52763/pjsir.biol.sci.65.1.2022.62.66.

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Coconut water (Cocos nucifera L.) possesses natural hydrating qualities, functional health properties and various nutritional benefits. Lactobacillus species AAF-1 has been isolated and purified from coconut water. The isolated culture was screened for the production of extracellular secreted enzymes having industrial value. Growth of the Lactobacillus sp. AAF-1 on MRS agar containing respective substrates showed that the Lactobacillus sp. AAF-1 is the potential producer of amylase, protease, cellulase and beta galactosidase. Further cell free filtrates of the Lactobacillus sp. AAF-1 showed large zone of hydrolysis of starch, gelatin, cellulose and lactose that reflected the extracellular production of the above enzymes in culture medium at 50 °C. It has been observed that activities after 72 h of incubation in cell free filtrates of protease, amylase, cellulase and beta galactosidase as the zone of respective substrate hydrolysis measured as 10, 8, 6 and 10 mm respectively. Thus, Lactobacillus sp. AAF-1 could be the potential producer of the enzymes having industrial value.

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Udawatta, M. M., R. C. L. De Silva, and D. S. M. De Silva. "Surface modification of Trema orientalis wood biochar using natural coconut vinegar and its potential to remove aqueous calcium ions: column and batch studies." Environmental Engineering Research 28, no. 1 (January 5, 2022): 210522–0. http://dx.doi.org/10.4491/eer.2021.522.

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Recent investigations have revealed the harmful health effects of elevated calcium levels in drinking water. Chemically activated biochar is the most popular option for low-cost cation adsorption. However, most of these chemicals are hardly available for rural communities, corrosive, and difficult to handle by unskilled personnel. This study aimed to determine the ability of natural coconut vinegar, a common mild acid, to activate Trema orientalis wood biochar pyrolyzed at 300˚C (BC) as a facile, safe, and low-cost approach for aqueous calcium ion (Ca2+) removal. Column tests showed a two-fold increase of Ca2+ adsorption capacity and a ten-fold increase of Ca2+ retaining capacity of BC after activation with vinegar. The isotherm results were well correlated with the Langmuir model. The maximum Langmuir adsorption of the activated biochar (BC-A) was 9.96 mg/g. Ca2+ amount was determined using flame photometry. EDX analysis showed that the O/C ratio of BC increased from 0.07 to 0.13 after activation. FTIR and wettability studies showed increased oxygenated functional groups on the BC-A surface. The authors suggest a possible acid-catalyzed hydration of the C-O-C bridges of the biochar, introducing new hydroxyl/carbonyl/ester/carboxylic/lactone groups to the biochar surface due to the vinegar activation, enhancing Ca2+ adsorption through chemisorption.

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Seto, Jong. "On a Robust, Sensitive Cell-Free Method for Pseudomonas Sensing and Quantification in Microfluidic Templated Hydrogels." Micromachines 10, no. 8 (July 31, 2019): 506. http://dx.doi.org/10.3390/mi10080506.

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Through the use of droplet microfluidics to integrate cell-free activity into inert hydrogel beads, we have developed a platform that can perform biologically relevant functions without the need for cells. Specifically, cell-free lysates serve a utility in performing cellular functions and providing biologically relevant metabolic products without requiring the optimal biological conditions for cell growth and proliferation. By teasing out specific biological components that enable transcription and translation to occur, these cell-like functions can be reconstituted in vitro without requiring the entire cell and milieu of cellular organelles. This enables the optimization of synthetic biological circuits, either by concentration or logic switches, simply through the addition or removal of genetic components (plasmids, inducers, or repressors) of regulatory elements. Here, we demonstrate an application of cell-free processes that is robust and portable, independent of a substrate, to apply for sensing and reporting functions of a quorum-sensing molecule N-3-oxododecanoyl homoserine lactone (3OC12HSL) found crucial for pathological Pseudomonas aeruginosa infection. We develop an agarose bead platform that is easily adaptable and simply programmable to fit a variety of biological and chemical sensing applications for the utility of ease of delivery and activation in remote environments—even in conditions with very little hydration.

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Thomas, Javix, Oleksandr Sukhorukov, Wolfgang Jäger, and Yunjie Xu. "Direct Spectroscopic Detection of the Orientation of Free OH Groups in Methyl Lactate-(Water)1,2Clusters: Hydration of a Chiral Hydroxy Ester." Angewandte Chemie International Edition 53, no. 4 (December 4, 2013): 1156–59. http://dx.doi.org/10.1002/anie.201308466.

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Demetrescu, Ioana, Cristina Dumitriu, Georgeta Totea, Cristina Nica, Anca Dinischiotu, and Daniela Ionita. "Zwitterionic Cysteine Drug Coating Influence in Functionalization of Implantable Ti50Zr Alloy for Antibacterial, Biocompatibility and Stability Properties." Pharmaceutics 10, no. 4 (November 8, 2018): 220. http://dx.doi.org/10.3390/pharmaceutics10040220.

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The present paper aims atincreasing the bioperformance of implantable Ti50Zr alloy using zwitterionic cysteine drug coating. Aspects such as stability, biocompatibility, and antibacterial effects were investigated with the help of various methods such as infrared spectroscopy (FT-IR), scanning electronic microscopy (SEM), electrochemical methods, contact angle determinations and cell response. The experimental data of zwitterionic cysteine coating indicate the existence of a hydration layer due to hydrophilic groups evidenced in FT-IR which is responsible for the decrease of contact angle and antibacterial capabilities. The electrochemical stability was evaluatedbased on Tafel plots and electrochemical impedance spectroscopy (EIS). The cell response to cysteine was determined with gingival fibroblasts measuring lactate dehydrogenase (LDH) activity, concentrations of nitric oxide (NO) and intracellular level of reactive oxygen species (ROS). All experimental results supported the increase of stability and better cells response of implantable Ti50Zr alloy coated with zwitterionic cysteine drug. The antibacterial index was measured against Staphylococcus aureus and Escherichia coli. It was demonstrated that the coating enhanced the production of intracellular ROS in time, which subsequently caused a significant increase in antibacterial index.

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MUNHOZ-FILHO, Clewis Henri, Fernando BATIGÁLIA, and Hamilton Luiz Xavier FUNES. "Clinical and therapeutic correlations in patients with slight acute pancreatitis." ABCD. Arquivos Brasileiros de Cirurgia Digestiva (São Paulo) 28, no. 1 (2015): 24–27. http://dx.doi.org/10.1590/s0102-67202015000100007.

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BACKGROUND: Acute pancreatitis is an inflammatory disease of the pancreas due to enzymatic autodigestion which can cause necrosis or multiple organ failure; its pathophysiology is not fully known yet. AIM: To evaluate the correlation between clinical and therapeutic data in patients with mild acute pancreatitis. METHODS: A retrospective study in 55 medical records of patients admitted with acute mild pancreatitis was realized to analyze the association between age, leukocytosis, serum glutamic-oxaloacetic transaminase and lactate dehydrogenase, glucose, antibiotics, time admission and Ranson´s scores. RESULTS: There was a positive association between less intensive care (strict hydration, analgesia and monitoring of vital signs), early antibiotic therapy (monotherapy), early return to diet after 48 hours and laboratory control of the serum amylase and lipase (high in the first week and decreasing after 10 days, without any prognostic value). CONCLUSIONS: Changes in the management of patients with mild acute pancreatitis, such as enteral nutrition, rational use of lower spectrum antibiotics and intensive care, have contributed significantly to the reduction of hospitalization time and mortality.

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Marinea, Marina, Ashling Ellis, Matt Golding, and Simon M. Loveday. "Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids." Foods 10, no. 1 (January 13, 2021): 154. http://dx.doi.org/10.3390/foods10010154.

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In this study, a model system of firm tofu (pressed gel) was prepared to study how the coagulation mechanism—acidification with glucono δ-lactone (GDL) or coagulation with magnesium sulphate (MgSO4)—affected the physical properties of the gels along with their in vitro proteolysis (or extent of proteolysis). The two types of gels were also fortified with 3.5 mM protocatechuic (PCA) and coumaric acid (CMA) to test whether they can be used as bioactive delivery systems. Texture analysis showed that all MgSO4-induced gels (fortified and control) had a higher hydration capacity and a weaker texture than the GDL-induced gels (p < 0.05). MgSO4 gels had almost double proteolysis percentages throughout the in vitro digestion and showed a significantly higher amino acid bioaccessibility than the GDL gels (essential amino acid bioaccessibility of 56% versus 31%; p < 0.05). Lastly, both gel matrices showed a similar phenolic acid release profile, on a percentage basis (~80% for PCA and ~100% for CMA). However, GDL gels delivered significantly higher masses of bioactives under simulated intestinal conditions because they could retain more of the bioactives in the gel after pressing. It was concluded that the coagulation mechanism affects both the macro- and microstructure of the soy protein pressed gels and as a result their protein digestibility. Both pressed gel matrices are promising delivery systems for bioactive phenolic acids.

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Journal articles on the topic 'Lactose hydration'

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