Fluid intake, hydration status and body mass changes in U-15 judo athletes during a training day

Despite numerous studies related to dehydration there is still a lack of scientific literature presenting hydration status and fluid intake of judo athletes during different periods. Therefore, the aim of this study was to investigate, fluid intake, hydration status and body weight changes of young judo athletes during a typical day of training in preparation period. Twenty-two young judo athletes (age: 12 ± 0.7 y, experience: 3.5 ± 1.1) voluntarily participated in this study. Hydration status and weight were examined in the morning, before and immediately after the training. All athletes trained 90 min and they consumed fluids ad libitum during the exercise. According to morning urine specific gravity (USG) values, 81.2% of the athletes were dehydrated while only 18.8% of the athletes were euhydrated. Pre-training urine measurements showed that 63.64% of the athletes presented dehydration and 77.27% of the athletes completed the training in dehydrated condition despite fluid availability during the training. Mean body weight loss during training was -0.64 ± 0.66%. It can be concluded that young judo athletes presented high prevalence of dehydration as indicated by USG values. Most of the athletes were dehydrated during a typical training day and completed the training in more dehydrated conditions compared to pre training values despite ad libitum fluid intake. It is of great importance to evaluate hydration status of the athletes before training to refrain from common practice of fluid restriction for weight loss and adverse effects of a persistent state of fluid deficit on physical and health related state.

Estudo de estabilidade de anfetaminas e produtos de biotransformação de cocaína e tetraidrocanabinol em amostras de urina seca em papel (dried urine spots) / Stability study of amphetamines, biotransformation products of cocaine and tetrahydrocannabinol in dried urine spots

O número de pessoas utilizando substâncias ilícitas de forma recreativa aumenta a cada ano, chamando a atenção de estudiosos de diversas áreas do conhecimento. Com isso, a demanda de exames toxicológicos exigida para trabalhadores, vítimas de crimes e esportistas também tem crescido. A amostra biológica mais utilizada para análises toxicológicas continua sendo a urina, visto que sua obtenção é menos invasiva, possibilita coletar grande volume de amostra e pode-se detectar substâncias até dias após ter ocorrido a exposição ou consumo. Entretanto, estas amostras necessitam de um grande volume físico para serem armazenadas e transportadas aos laboratórios, devendo ser mantidas em temperatura baixa e controlada para conservação. Outro ponto a se considerar é a quantidade de amostra insuficientemente coletada, ou extravasamento do conteúdo, contaminando outras amostras e muitas vezes, inviabilizando a análise. Uma alternativa recente para tais problemas é utilizar a técnica chamada de dried urine spots (DUS), onde poucos microlitros de urina são colocados em um papel absorvente e secos sob temperatura ambiente, preservando de agentes degradantes os componentes presentes na urina. Assim, o objetivo deste trabalho é avaliar a estabilidade das substâncias do presente estudo em alta temperatura, temperatura ambiente e em temperaturas de 4°C e -20°C. Para este fim, foi necessário desenvolver, validar e aplicar métodos de extração e determinação de anfetaminas e produtos de biotransformação de cocaína e tetraidrocanabinol carboxílico (THCCOOH) em amostras dried urine spot, utilizando cromatografia líquida acoplada à espectrometria de massas. Os picos foram identificados por UPLC-ESI-MS/MS, com tempo total de 5 mins utilizando fase A- água, formiato de amônio e 0,1% ácido fórmico, e B- metanol: acetonitrila (6:4) + 0,1% de ácido fórmico. A extração foi feita utilizando acetonitrila: metanol: acetona (1:1:1) +ácido fórmico 0,1%. Não foi possível iniciar a validação de THCCOOH, visto uma possível complexação do analito com o papel. Para as outras substâncias, o método cromatográfico desenvolvido se mostrou eficiente e seletivo, com LOD e LOQ de 10 ng/mL para todos os analitos, sendo linear até 1000 ng/mL, atendeu as especificações de precisão e exatidão e carryover. As amostras permaneceram estáveis ao longo de 32 dias nas temperaturas estudadas, demonstrando a segurança em se utilizar a técnica de DUS para armazenamento e transporte de amostras biológicas dentro da faixa de temperatura do estudo até 32 dias

The number of people using illegal substances in a recreational way increases each year, drawing the attention of scholars from different areas of knowledge. As a result, the demand for workplaces drug tests, toxicological tests for victims of crimes and dopping has also grown. The biological sample most used for toxicological tests remains urine, since obtaining it is less invasive, it is possible to collect a large volume of sample and it is possible to detect substances up to days after exposure or consumption has occurred. However, these samples require a large physical volume to be stored and transported to the laboratories, and must be kept at a low temperature for conservation. Another point to consider is the amount of sample insufficiently collected, or leakage of the content, causing contamination of other samples and often making the analysis unfeasible. A recent alternative to such problems is to use "dried urine spots" (DUS), where few microliters of urine are placed on absorbent paper and dried at room temperature, preserving the components present in the urine from degrading agents. Thus, the objective of this work is to evaluate the stability of the substances in this study at high temperature, room temperature and at temperatures of 4°C and -20°C. For this purpose, it was necessary to develop, validate and apply methods of extraction and determination of amphetamines and biotransformation products of cocaine and carboxylic tetrahydrocannabinol (THCCOOH) in dried urine spot samples, using liquid chromatography coupled to mass spectrometry (LC-MS). The peaks were identified liquid chromatography coupled to a mass spectrometer (UPLC-ESI-MS/MS), with a total time of 5 mins using phase A- water, ammonium formate and 0.1% formic acid, and B- methanol: acetonitrile (6:4) + 0.1% formic acid. Extraction was done using acetonitrile: methanol: acetone (1:1:1) + 0.1% formic acid. It was not possible to perform the validation of THCCOOH, given a possible complexation of the analyte with the paper. To the others substances, the chromatographic method developed proved to be efficient and selective, with LOD and LOQ of 10 ng/mL for all analytes, being linear up to 1000 ng/mL, meeting the specifications of precision and accuracy and carryover. The samples remained stable for 32 days at the temperatures studied, demonstrating the safety of using the DUS technique for storage and transport of biological samples until 32 days on temperature range studied

A Method to Monitor the NAD+ Metabolome-From Mechanistic to Clinical Applications.

Nicotinamide adenine dinucleotide (NAD+) and its reduced form (NADH) are coenzymes employed in hundreds of metabolic reactions. NAD+ also serves as a substrate for enzymes such as sirtuins, poly(ADP-ribose) polymerases (PARPs) and ADP-ribosyl cyclases. Given the pivotal role of NAD(H) in health and disease, studying NAD+ metabolism has become essential to monitor genetic- and/or drug-induced perturbations related to metabolic status and diseases (such as ageing, cancer or obesity), and its possible therapies. Here, we present a strategy based on liquid chromatography-tandem mass spectrometry (LC-MS/MS), for the analysis of the NAD+ metabolome in biological samples. In this method, hydrophilic interaction chromatography (HILIC) was used to separate a total of 18 metabolites belonging to pathways leading to NAD+ biosynthesis, including precursors, intermediates and catabolites. As redox cofactors are known for their instability, a sample preparation procedure was developed to handle a variety of biological matrices: cell models, rodent tissues and biofluids, as well as human biofluids (urine, plasma, serum, whole blood). For clinical applications, quantitative LC-MS/MS for a subset of metabolites was demonstrated for the analysis of the human whole blood of nine volunteers. Using this developed workflow, our methodology allows studying NAD+ biology from mechanistic to clinical applications.

Short-term metabolic disruptions in urine of mouse models following exposure to low doses of oxygen ion radiation.

Molecular alterations as a result of exposure to low doses of high linear energy transfer (LET) radiation can have deleterious short- and long-term consequences on crew members embarking on long distance space missions. Oxygen ions (16O) are among the high LET charged particles that make up the radiation environment inside a vehicle in deep space. We used mass spectrometry-based metabolomics to characterize urinary metabolic profiles of male C57BL/6J mice exposed to a single dose of 0.1, 0.25 and 1.0 Gy of 16O (600 MeV/n) at 10 and 30 days post-exposure to delineate radiation-induced metabolic alterations. We recognized a significant down regulation of several classes of metabolites including cresols and tryptophan metabolites, ketoacids and their derivatives upon exposure to 0.1 and 0.25 Gy after 10 days. While some of these changes reverted to near normal by 30 days, some metabolites including p-Cresol sulfate, oxalosuccinic acid, and indoxylsulfate remained dysregulated at 30 days, suggesting long term prognosis on metabolism. Pathway analysis revealed a long-term dysregulation in multiple pathways including tryptophan and porphyrin metabolism. These results suggest that low doses of high-LET charged particle irradiation may have long-term implications on metabolic imbalance.

Deep Phenotyping of Urinary Leukocytes by Mass Cytometry Reveals a Leukocyte Signature for Early and Non-Invasive Prediction of Response to Treatment in Active Lupus Nephritis.

Non-invasive biomarkers are necessary for diagnosis and monitoring disease activity in lupus nephritis (LN) to circumvent risks and limitations of renal biopsies. To identify new non-invasive cellular biomarkers in the urine sediment of LN patients, which may reflect kidney inflammation and can be used to predict treatment outcome, we performed in-depth urinary immune cell profiling by mass cytometry. We established a mass cytometric workflow to comparatively analyze the cellular composition of urine and peripheral blood (PB) in 13 patients with systemic lupus erythematosus (SLE) with active, biopsy-proven proliferative LN. Clinical and laboratory data were collected at the time of sampling and 6 months after induction of therapy in order to evaluate the clinical response of each patient. Six patients with different acute inflammatory renal diseases were included as comparison group. Leukocyte phenotypes and composition differed significantly between urine and paired PB samples. In urine, neutrophils and monocytes/macrophages were identified as the most prominent cell populations comprising together about 30%-83% of nucleated cells, while T and B lymphocytes, eosinophils, and natural killer (NK) cells were detectable at frequencies of <10% each. The majority of urinary T cells showed phenotypical characteristics of activated effector memory T cells (EM) as indicated by the co-expression of CD38 and CD69 - a phenotype that was not detectable in PB. Kidney inflammation was also reflected by tissue-imprinted macrophages, which phenotypically differed from PB monocytes by an increased expression of HLA-DR and CD11c. The presence of activated urinary T cells and macrophages could be used for differential diagnosis of proliferative LN forms and other renal pathologies. Most interestingly, the amount of EM in the urine sediment could be used as a biomarker to stratify LN patients in terms of response to induction therapy. Deep immunophenotypic profiling of urinary cells in LN allowed us to identify a signature of activated T cells and macrophages, which appear to reflect leukocytic infiltrates in the kidney. This explorative study has not only confirmed but also extended the knowledge about urinary cells as a future non-invasive biomarker platform for diagnosis and precision medicine in inflammatory renal diseases.

Loading-induced antitumor capability of murine and human urine.

While urine has been considered as a useful bio-fluid for health monitoring, its dynamic changes to physical activity are not well understood. We examined urine's possible antitumor capability in response to medium-level, loading-driven physical activity. Urine was collected from mice subjected to 5-minute skeletal loading and human individuals before and after 30-minute step aerobics. Six cancer cell lines (breast, prostate, and pancreas) and a mouse model of the mammary tumor were employed to evaluate the effect of urine. Compared to urine collected prior to loading, urine collected post-activity decreased the cellular viability, proliferation, migration, and invasion of tumor cells, as well as tumor weight in the mammary fat pad. Detection of urinary volatile organic compounds and ELISA assays showed that the loading-conditioned urine reduced cholesterol and elevated dopamine and melatonin. Immunohistochemical fluorescent images presented upregulation of the rate-limiting enzymes for the production of dopamine and melatonin in the brain. Molecular analysis revealed that the antitumor effect was linked to the reduction in molecular vinculin-linked molecular force as well as the downregulation of the Lrp5-CSF1-CD105 regulatory axis. Notably, the survival rate for the high expression levels of Lrp5, CSF1, and CD105 in tumor tissues was significantly lowered in the Cancer Genome Atlas database. Collectively, this study revealed that 5- or 10-minute loading-driven physical activity was sufficient to induce the striking antitumor effect by activating the neuronal signaling and repressing cholesterol synthesis. The result supported the dual role of loading-conditioned urine as a potential tumor suppressor and a source of diagnostic biomarkers.

Urine as a Main Effector in Urological Tissue Engineering-A Double-Edged Sword.

In order to reconstruct injured urinary tract tissues, biodegradable scaffolds with autologous seeded cells are explored in this work. However, when cells are obtained via biopsy from individuals who have damaged organs due to infection, congenital disorders, or cancer, this can result in unhealthy engineered cells and donor site morbidity. Thus, neo-organ construction through an alternative cell source might be useful. Significant advancements in the isolation and utilization of urine-derived stem cells have provided opportunities for this less invasive, limitless, and versatile source of cells to be employed in urologic tissue-engineered replacement. These cells have a high potential to differentiate into urothelial and smooth muscle cells. However, urinary tract reconstruction via tissue engineering is peculiar as it takes place in a milieu of urine that imposes certain risks on the implanted cells and scaffolds as a result of the highly cytotoxic nature of urine and its detrimental effect on both growth and differentiation of these cells. Both of these projections should be tackled thoughtfully when designing a suitable approach for repairing urinary tract defects and applying the needful precautions is vital.

Studying the urine microbiome in superficial bladder cancer: samples obtained by midstream voiding versus cystoscopy.

BACKGROUND: Preliminary data suggest that the urinary microbiome may play a role in bladder cancer. Information regarding the most suitable method of collecting urine specimens is needed for the large population studies needed to address this. To compare microbiome metrics resulting from 16S ribosomal RNA gene sequencing between midstream, voided specimens and those obtained at cystoscopy. METHODS: Adults, with a history of superficial urothelial cell carcinoma (non-muscle invasive bladder cancer) being followed with periodic surveillance cystoscopy had a urine sample collected by a mid-stream, voided technique and then from the bladder at cystoscopy. Urine samples underwent 16S ribosomal RNA gene sequencing on the Illumina MiSeq platform. RESULTS: 22 subjects (8 female, 14 male) were included. There was no significant difference in beta diversity (diversity between samples) in all samples between collection methods. However, analysis by sex revealed a difference between voided and cystoscopy samples from the same individual in males (p = 0.006, Adonis test) but not in females (p = 0.317, Adonis test). No differences were seen by collection method in any alpha diversity (diversity within a sample) measurement or differential abundance of taxa. CONCLUSIONS: Beta diversity of the urine microbiome did differ by collection method for males only. This suggests that the urinary microbiomes of the two collection methods are not equivalent to each other, at least in males, which is the sex that bladder cancer occurs most frequently in. Therefore, the same collection method within a given study should be used.

Science and fiction in critical care: established concepts with or without evidence?

In the absence of evidence, therapies are often based on intuition, belief, common sense or gut feeling. Over the years, some treatment strategies may become dogmas that are eventually considered as state-of-the-art and not questioned any longer. This might be a reason why there are many examples of "strange" treatments in medical history that have been applied in the absence of evidence and later abandoned for good reasons.In this article, five dogmas relevant to critical care medicine are discussed and reviewed in the light of the available evidence. Dogma #1 relates to the treatment of oliguria with fluids, diuretics, and vasopressors. In this context, it should be considered that oliguria is a symptom rather than a disease. Thus, once hypovolaemia can be excluded as the underlying reason, there is no justification for giving fluids, which may do more harm than good in euvolaemic or hypervolaemic patients. Similarly, there is no solid evidence for forcing diuresis by administering vasopressors and loop diuretics. Dogma #2 addresses the treatment of crush syndrome patients with aggressive fluid therapy using NaCl 0.9%. In fact, this treatment may aggravate renal injury by iatrogenic metabolic acidosis and subsequent renal hypoperfusion. Dogma #3 concerns the administration of NaCl 0.9% to patients undergoing kidney transplantation. Since these patients are usually characterised by hyperkalaemia, the potassium-free solution NaCl 0.9%, containing exclusively 154 mmol/l of sodium and chloride ions each, is often considered as the fluid of choice. However, large volumes of chloride-rich solutions cause hyperchloraemic acidosis in a dose-dependent manner and induce a potassium shift to the extracellular space, thereby increasing serum potassium levels. Thus, balanced electrolyte solutions are to be preferred in this setting. Dogma #4 relates to the fact that enteral nutrition is often withheld for patients with high residual gastric volume due to the theoretical risk of gastro-oesophageal reflux, potentially resulting in aspiration pneumonitis. Despite controversial discussions, there is no clinical data supporting that residual gastric volume should be generally measured, especially not in patients without a gastro-intestinal surgery and/or motility disorders. Clinical evidence rather suggests that abandoning residual gastric volume monitoring does not increase the incidence of pneumonia, but may benefit patients by facilitating adequate enteral feeding. Finally, dogma #5 is about sedating all mechanically ventilated patients because "fighting" against the respirator may cause insufficient ventilation. This concern needs to be balanced against the unwanted consequences of sedation, such as prolonged mechanical ventilation and intensive care unit length of stay as well as increased risk of delirium. Modern concepts based on adequate analgesia and moderate to no sedation appear to be more suitable.In conclusion, dogmas are still common in clinical practice. Since science rather than fiction should govern our actions in intensive care medicine, it is important to remain critical and challenge long established concepts, especially when the underlying evidence is weak or non-existing.

Hydration Marker Diagnostic Accuracy to Identify Mild Intracellular and Extracellular Dehydration.

Identifying mild dehydration (≤2% of body mass) is important to prevent the negative effects of more severe dehydration on human health and performance. It is unknown whether a single hydration marker can identify both mild intracellular dehydration (ID) and extracellular dehydration (ED) with adequate diagnostic accuracy (≥0.7 receiver-operating characteristic-area under the curve [ROC-AUC]). Thus, in 15 young healthy men, the authors determined the diagnostic accuracy of 15 hydration markers after three randomized 48-hr trials; euhydration (water 36 ml·kg-1·day-1), ID caused by exercise and 48 hr of fluid restriction (water 2 ml·kg-1·day-1), and ED caused by a 4-hr diuretic-induced diuresis begun at 44 hr (Furosemide 0.65 mg/kg). Body mass was maintained on euhydration, and dehydration was mild on ID and ED (1.9% [0.5%] and 2.0% [0.3%] of body mass, respectively). Urine color, urine specific gravity, plasma osmolality, saliva flow rate, saliva osmolality, heart rate variability, and dry mouth identified ID (ROC-AUC; range 0.70-0.99), and postural heart rate change identified ED (ROC-AUC 0.82). Thirst 0-9 scale (ROC-AUC 0.97 and 0.78 for ID and ED) and urine osmolality (ROC-AUC 0.99 and 0.81 for ID and ED) identified both dehydration types. However, only the thirst 0-9 scale had a common dehydration threshold (≥4; sensitivity and specificity of 100%; 87% and 71%, 87% for ID and ED). In conclusion, using a common dehydration threshold ≥4, the thirst 0-9 scale identified mild intracellular and ED with adequate diagnostic accuracy. In young healthy adults', thirst 0-9 scale is a valid and practical dehydration screening tool.

ASP6432, a type 1 lysophosphatidic acid receptor antagonist, reduces urethral function during urine voiding and improves voiding dysfunction.

Current pharmacotherapies for voiding dysfunctions are in need of improvement. Lysophosphatidic acid (LPA) is a phospholipid that contracts the urethra by activating type 1 LPA receptors (LPA1). However, the role of LPA1 in regulating urethral tonus during urine voiding which primarily affects the voiding function has not been investigated. To elucidate the role of LPA1 in the regulation of urethral tonus during urine voiding, we investigated the effects of ASP6432, a novel LPA1 antagonist, and the α1-adrenoceptor antagonist tamsulosin on urethral perfusion pressure (UPP) at the filling phase (UPPbase) and the minimum UPP at the voiding phase (UPPnadir) in anesthetized rats under isovolumetric conditions. We further evaluated the effects of ASP6432 and tamsulosin on voiding dysfunction characterized by changes in post-void residual urine (PVR) and voiding efficiency (VE) induced by the nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME) in conscious rats using single cystometry. ASP6432 dose-dependently decreased UPPbase and UPPnadir, while tamsulosin reduced UPPbase but did not change UPPnadir. ASP6432 dose-dependently suppressed the L-NAME-induced increase in PVR and decrease in VE, whereas tamsulosin did not affect either PVR or VE. We demonstrate that ASP6432 reduced UPPnadir and ameliorated L-NAME-induced voiding dysfunction, neither of which were affected by tamsulosin. Our study results suggest that LPA1 has a significant role in regulating urethral tonus during urine voiding, and highlight the potential of ASP6432 for improving voiding dysfunctions associated with various lower urinary tract diseases.

Urine can speed up the re-epithelialization process of prostatic urethra wounds by promoting the proliferation and migration of prostate epithelial cells.

OBJECTIVES: The present study aimed to investigate the influence of urine on re-epithelialization in canine prostatic urethra after prostatectomy and explore possible causes. METHOD: We established two groups of prostatic canine models. The first group contained urine that canines underwent the surgery by two-micron laser resection of the prostate-tangerine technique (TmLRP-TT), and no transurethral catheter was required. The second group was without urine that canines accepted the surgery by TmLRP-TT add ureter skin ostomy urine bypass. Histopathology of re-epithelialization of repair in trauma in canine prostatic urethra was observed by hematoxylin and eosin (HE) staining, and immunochemistry was used to determine the expression of transforming growth factor-ß1 (TGF-ß1). Human prostate epithelial line (BPH-1) cells were cultured with or without urine and the abilities of proliferation and migration were tested by CCK-8 and transwell assays, respectively. RESULTS: The histology displayed that there was distinct proliferation of prostatic cell under the wound after 3 days, re-epithelialization began after 9 days, and finished after 28 days at urine group. The TGF-ß1 like-IR in prostatic epithelium cells and fibroblast cells under the wound at urine group were strikingly increased as compared with the cells at no urine group after 3, 9, and 11 days, respectively (p < 0.05). In CCK-8 and Transwell assays, an increase of cells' proliferation and migration was detected in urine culture group compared with no urine culture group (p < 0.05). CONCLUSION: Urine may speed up the re-epithelialization process for prostatic urethra wounds by promoting proliferation and migration of prostate epithelial cells.

Preoperative Urinary pH is Associated with Acute Kidney Injury After Cardiac Surgery in Non-Diabetic Patients.

BACKGROUND: Acute kidney injury is a common complication of cardiac surgery that increases morbidity and mortality. The present study aims to analyze the association of preoperative urinary pH with acute kidney injury after isolated coronary artery bypass graft surgery (CABG). METHODS: We retrospectively reviewed the data of 270 adult non-diabetic patients who underwent isolated CABG surgery with normal renal function. The perioperative data of the patients included demographic data, laboratory findings, morbidity, and mortality. The patient population was divided into four groups: Group I, patients with preoperative urinary pH=5; Group II, patients with preoperative urinary pH=5.5; Group III, patients with preoperative urinary pH=6-6.5; and Group IV, patients with preoperative urinary pH ≥ 7.0. Kidney injury was interpreted according to the Kidney Disease: Improving Global Outcomes (KDIGO). RESULTS: There were 108 patients (40%) in Group I, 44 patients (16.3%) in Group II, 78 patients (28.9%) in Group III, and 40 patients (14.8%) in Group IV. Postoperative acute kidney injury (AKI) occurred in 39 patients (36.1%) in Group I, 4 patients (9.1%) in Group II, and 2 patients (2,5%) in Group III. None of the patients developed AKI in Group IV. Renal replacement therapy was required in 8 patients (2.3%) (6 patients from Group I; 2 patients from Group II; P = .016). Thirty-day mortality occurred in 5 patients (1.9%) (5 patients from Group I; none from other groups; P =  .017). All of the patients required renal replacement therapy. Logistic regression analysis revealing the presence of lower pH levels preoperatively was shown to be associated with increased incidence of postoperative AKI (OR: 0.193; 95% CI: 0.103-0.361; P < .001). CONCLUSION: Low preoperative urinary pH (≤5.5) results in severe acute kidney injury and increases the rate of morbidity and mortality after isolated CABG.

Prevalence of voluntary dehydration according to urine osmolarity in elementary school students in the metropolitan region of São Paulo, Brazil

OBJECTIVES: To evaluate the prevalence of voluntary dehydration based on urine osmolarity in elementary school students from two public educational institutions in the metropolitan region of São Paulo and evaluate whether there is a relationship between voluntary dehydration and nutritional status or socioeconomic status. METHODS: Analytical cross-sectional study with students from two public schools in the city of Osasco. The determination of urine osmolarity was performed using the freezing method of the Advanced® Osmometer Model 3W2. Urine osmolarity greater than 800 mOsm/kg H2O was considered voluntary dehydration. During data collection, the weights and heights of the students, environmental temperatures and air humidity levels were obtained. RESULTS: A total of 475 students aged six to 12 years were evaluated, of whom 188 were male. Voluntary dehydration occurred in 63.2% of the students and was more frequent in males than in females. The prevalence of voluntary dehydration was more frequent in males aged six to nine years than in females. However, no statistically significant difference was observed between males and females aged 10 to 12 years. No association was found between voluntary dehydration and nutritional status or socioeconomic status. CONCLUSION: The prevalence of voluntary dehydration was high in elementary school students and was more frequent in males. No association was found between voluntary dehydration and nutritional or socioeconomic status.

Factors associated with residual urine volume preservation in patients undergoing hemodialysis for end-stage kidney disease in Kinshasa.

BACKGROUND: Decreased residual urine volume (RUV) is associated with higher mortality in hemodialysis (HD). However, few studies have examined RUV in patients on HD in Sub-Saharan Africa. The aim of this study was to identify predictors of RUV among incident hemodialysis patients in Kinshasa. METHODS: This historical cohort study enrolled 250 patients with ESRD undergoing hemodialysis between January 2007 and July 2013 in two hemodialysis centers in Kinshasa. RUV were collected over 24 h at the initiation of HD and 6 and 12 months later during the interdialytic period. We compared the baseline characteristics of the patients according to their initial RUV (≤ 500 ml/day vs >  500 ml/day) using Student's t, Mann-Whitney U and Chi2 tests. Linear mixed-effects models were used to search for predictors of decreased RUV by adding potentially predictive baseline covariates of the evolution of RUV to the effect of time: age, sex, diabetes mellitus, hypertension, diastolic blood pressure, diuretics, angiotensin conversion enzyme inhibitors (ACEI), angiotensin receptor blockers, hypovolemia, chronic tubulointerstitial nephropathy, left ventricular hypertrophy and initial hemodialysis characteristic. A value of p < 0.05 was considered the threshold of statistical significance. RESULTS: The majority of hemodialysis patients were male (68.8%, sex ratio 2.2), with a mean age of 52.5 ± 12.3 years. The population's RUV decreased with time, but with a slight deceleration. The mean RUV values were 680 ± 537 ml/day, 558 ± 442 ml/day and 499 ± 475 ml/day, respectively, at the initiation of HD and at 6 and 12 months later. The use of ACEI at the initiation of HD (beta coefficient 219.5, p < 0.001) and the presence of chronic tubulointerstitial nephropathy (beta coefficient 291.8, p = 0.007) were significantly associated with RUV preservation over time. In contrast, the presence of left ventricular hypertrophy at the initiation of HD was significantly associated with decreased RUV over time (beta coefficient - 133.9, p = 0.029). CONCLUSIONS: Among incident hemodialysis patients, the use of ACEI, the presence of chronic tubulointerstitial nephropathy and reduced left ventricular hypertrophy are associated with greater RUV preservation in the first year of dialysis.

Mode of Surgical Injury Influences the Source of Urothelial Progenitors during Bladder Defect Repair.

The bladder urothelium functions as a urine-blood barrier and consists of basal, intermediate, and superficial cell populations. Reconstructive procedures such as augmentation cystoplasty and focal mucosal resection involve localized surgical damage to the bladder wall whereby focal segments of the urothelium and underlying submucosa are respectively removed or replaced and regeneration ensues. We demonstrate using lineage-tracing systems that urothelial regeneration following augmentation cystoplasty with acellular grafts exclusively depends on host keratin 5-expressing basal cells to repopulate all lineages of the de novo urothelium at implant sites. Conversely, repair of focal mucosal defects not only employs this mechanism, but in parallel host intermediate cell daughters expressing uroplakin 2 give rise to themselves and are also contributors to superficial cells in neotissues. These results highlight the diversity of urothelial regenerative responses to surgical injury and may lead to advancements in bladder tissue engineering approaches.

Urine flow rate monitoring in hypovolemic multiple trauma patients.

BACKGROUND: The urine output is an important clinical parameter of renal function and blood volume status, especially in critically ill multiple trauma patients. In the present study, the minute-to-minute urine flow rate and its variability were analyzed in hypotensive multiple trauma patients during the first 6 h of their ICU (intensive care unit) stay. These parameters have not been previously reported. METHODS: The study was retrospective and observational. Demographic and clinical data were extracted from the computerized Register Information Systems. A total of 59 patients were included in the study. The patients were divided into two study groups. Group 1 consisted of 29 multiple trauma patients whose systolic blood pressure was greater than 90 mmHg on admission to the ICU and who were consequently deemed to be hemodynamically compromised. Group 2 consisted of 30 patients whose systolic blood pressure was less than 90 mmHg on admission to the ICU and who were therefore regarded as hemodynamically uncompromised. RESULTS: The urine output and urine flow rate variability during the first 6 h of the patients' ICU stay was significantly lower in group 2 than in group 1 (p < 0.001 and 0.006 respectively). Statistical analysis by the Pearson method demonstrated a strong direct correlation between decreased urine flow rate variability and decreased urine output per hour (R = 0.17; P = 0.009), decreased mean arterial blood pressure (R = 0.24; p = 0.001), and increased heart rate (R = 0.205; p = 0.001). CONCLUSION: These findings suggest that minute-to-minute urine flow rate variability is a reliable incipient marker of hypovolemia and that it should therefore take its place among the parameters used to monitor the hemodynamic status of critically ill multiple trauma patients.

Outcomes Associated with Reducing the Urine Alkalinization Threshold in Patients Receiving High-Dose Methotrexate.

STUDY OBJECTIVES: Urine alkalinization increases methotrexate (MTX) solubility and reduces the risk of nephrotoxicity. The objectives of this study were to determine whether a reduction in the urine pH threshold from 8 to 7 in patients receiving high-dose methotrexate (HDMTX) results in a shorter length of hospital stay, delayed MTX clearance, or higher rates of nephrotoxicity; and to determine whether specific factors were associated with prolonged MTX clearance. DESIGN: Retrospective cohort study. SETTING: Hematology service of a large university-affiliated teaching hospital in Ottawa, Canada. PATIENTS: Sixty-five adults with 150 HDMTX exposures who had elective admissions for HDMTX between September 1, 2014, and December 18, 2015, were included. Thirty-four patients (with 79 HDMTX exposures) had their urine alkalinized to a pH of 8 or higher, and 31 patients (with 71 HDMTX exposures) had their urine alkalinized to a pH of 7 or higher, after an institutional change in the urine pH threshold from 8 to 7 was implemented on May 1, 2015. MEASUREMENTS AND MAIN RESULTS: Data related to patient demographics, urine alkalinization, MTX serum concentration monitoring, hospital length of stay, and renal function were collected retrospectively from patients' electronic health records. Lowering the urine pH threshold from 8 to 7 did not significantly affect hospital length of stay (absolute difference 3.5 hrs, 95% confidence interval -4.0 to 10.9) or clearance of MTX (elimination rate constant 0.058 in the pH of 7 or higher group vs 0.064 in the pH of 8 or higher group, p=0.233). Nephrotoxicity rates were similar between groups (15.5% in the pH of 7 or higher group vs 10.1% in the pH of 8 or higher group, p=0.34). Higher MTX dose and interacting medications (e.g., proton pump inhibitors and sulfonamide antibiotics) were significantly associated with delayed MTX elimination. CONCLUSION: No significant differences in HDMTX-associated hospital length of stay, MTX clearance, or rates of nephrotoxicity were noted between patients in the urine pH of 7 or higher and 8 or higher groups. Interacting medications and higher MTX dose were associated with delayed MTX elimination, suggesting that a closer review of interacting medications before HDMTX administration may be warranted.

Contexto escolar e hábitos miccionais: estudo transversal com escolares do distrito federal / Contexto escolar y hábitos miccionales: estudio transversal con escolares del distrito federal / School setting and voiding habits: a cross-sectional study among school-aged children from the federal district

RESUMO Estudo transversal realizado em oito escolas públicas e particulares do Riacho Fundo,(Distrito Federal),com escolares deseis a 12 anos, com o objetivo de avaliar a frequência de ida e permissão para uso do toalete na escola, sob a perspectiva do escolar, assim como mensurar a taxa de ocorrência e o impacto da experiência de ter tido alguma vez na vida um evento de perda urinária no contexto escolar. A coleta de dados incluiu entrevista por meio de perguntas-chave desenvolvidas pelas pesquisadoras. A análise dos dados incluiu técnicas básicas de análise exploratória de dados como,frequência absoluta e relativa, calculadas no programa Statistical Package for the Social Sciences. Das 86 crianças participantes da pesquisa, 73% (n=63) relataram irtodos os dias ao toalete escolar, ao passo que as que afirmam não utilizar o toalete apontaram como justificativas a falta de vontade, a falta de papel higiênico nos toaletes e a falta de privacidade ou problema com as portas. Quanto à permissão para o uso do toalete, 66% (n=57) afirmaram poder ir sempre que tivessem vontade. A experiência de perda urinária na escola foi relatada por17 (20%) crianças e apresentou impacto altamente negativo sob a perspectiva do escolar.

RESUMEN Se realizó un estudio transversal en 8 escuelas públicas y privadas del Riacho Fundo (Distrito Federal) con escolares de 6 a 12 años que tuvo como objetivo evaluar la frecuencia de idas y permiso al baño en la escuela bajo la perspectiva del escolar, así como medir la tasa de ocurrencia y el impacto de la experiencia de haber tenido alguna vez en la vida pérdida urinaria en el contexto escolar. La recolección de datos incluyó entrevistas con preguntas claves desarrolladas por los investigadores. El análisis de datos incluyó las técnicas básicas de análisis exploratorio de datos como la frecuencia absoluta y relativa, calculada utilizando el programa Statistical Package for the Social Sciences. De los 86 niños participantes, el 73% (n = 63) informaron ir todos los días al baño de la escuela, las justificaciones para no ir fueron falta de voluntad, la falta de papel higiénico y la falta privacidad o problemas con las puertas. En referencia al uso del baño, el 66% (n = 57) dijo que podían ir cuando tuviesen necesidad. La experiencia de pérdida urinaria en la escuela fue reportada por 17 (20%) niños y presentó un impacto muy negativo desde la perspectiva del escolar.

ABSTRACT This was a cross-sectional study conducted in 8 public and private schools of Riacho Fundo (Federal District), with children between 6 and 12 years old, that aimed to evaluate their frequency of going to the school restroom and permission to use it from the children's perspective, as well as to measure the rate of occurrence and impact of the experience of having had some once in a lifetime urinary leakage in the school setting. Data collection included interviews with key questions developed by the researchers. Data analysis included basic techniques of exploratory data analysis such as absolute and relative frequencies calculated using the Statistical Package for Social Sciences program. Out of 86 participating children, 73% (n = 63) reported going every day to the school restroom while those reporting not going pointed out reasons as they did not need to, lack of toilet paper, and lack of privacy or problems with the stalls' doors. Regarding permission to use the restroom, 66% (n = 57) stated being allowed to go whenever they needed. The experience of urinary incontinence at school was reported by 17 (20%) children and presented as a highly negative impact from their perspective.

Validación del método enzimático para la determinación de creatinina en suero y orina / Validation of the enzymatic method for the estimation of serum and urine creatinine

Introducción: la creatinina es un importante marcador de control y monitoreo en diferentes patologías renales. Objetivo: validar un método enzimático colorimétrico de análisis cinético para la determinación de creatinina en suero y orina desarrollado con reactivos de producción nacional para su aplicación en los laboratorios clínicos. Métodos: el método enzimático se aplica para determinaciones cinéticas a partir de la medición espectrofotométrica a una longitud de onda de 550 nm de la quinoneimina formada. Se realizó la validación evaluando los parámetros especificidad, linealidad, precisión, exactitud, límite de detección y de cuantificación, cumpliendo con las regulaciones vigentes en Cuba. Resultados: el método fue suficientemente específico para el objetivo propuesto, brindó una respuesta lineal desde 26,52 a 2 652 µmol/L en suero y de 884 a 26 520 µmol/L en orina, presentó una elevada precisión, exactitud y adecuados límites de detección y cuantificación. Conclusión: al cumplir el método evaluado con las exigencias regulatorias vigentes se puede emplear en los laboratorios clínicos del país, para la determinación de creatinina en suero y orina(AU)

Introduction: creatinine is an important control and monitoring marker in various kidney pathologies. Objectives: to validate a colorimetric enzymatic method of kinetic analysis developed with Cuban-made reagents, in order to determine the serum and urine creatinine for future application in the clinical laboratories. Methods: the enzymatic method is used for kinetic determinations based on the spectrophotometric measurement at 550nm wavelength of the formed quinoneimine. The validation evaluated the parameters specificity, linearity, precision, accuracy, detection and quantitation limits in compliance with the present Cuban regulations. Results: the method was specific for the suggested objective; provided linear response from 26,52 to 2 652 µmol/L in serum and from 884 to 26 520 µmol/L in urine; had great precision and accuracy and its detection and quantitation limits were adequate. Conclusions: since the evaluated method fulfilled the present regulatory demands, it may be used in the domestic clinic laboratories to determine serum and urine creatinine(AU)