Water Handling Research Articles

Microbial and Heavy Metal Evaluation of Sachet Drinking Water in the Hohoe Municipality, Ghana

Aim: To study microbial and heavy metal composition in sachet drinking water in the Hohoe municipality in the Volta Region of Ghana. Place and Duration of Study: The study was conducted in the Hohoe Municipality in the Volta region of Ghana and laboratory analyses were carried out at the Microbiology laboratory of the Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology between June 2018 and May 2019. Study Design: Cross-sectional study. Methodology: The study was conducted on three samples each of eight different brands of sachet water randomly selected across various towns from street vendors in the Hohoe Municipality for microbial and chemical analyses. 10ml of each sample was aliquoted under sterile conditions and cultured overnight in nutrient media. Enumeration and qualitative analyses of bacteria were performed using the pour plate method. For heavy metal analysis, 5 ml of concentrated HNO3 was added to 40 ml of each sample and heated at 100 °C for 20–30 minutes to reduce the volume to 20 ml. 30ml of distilled water was subsequently added and the mixture was analyzed using flame atomic absorption Spectroscopy. Results: Out of total twenty-four samples analyzed, 50% of the sachet water was contaminated with total and fecal coliforms with the highest average coliform forming unit (cfu/ml) being 16.2 x 105 cfu/ml and the least 0.01 x 105 cfu/ml. There were Klebsiella spp, and Pseudomonas aeruginosa contamination in 50% of the sachet drinking water but Salmonella spp and E. coli were absent in all brands. Chromium was detected to be within the range of 0.40mg/L - 0.56mg/L in the sachet water while zinc was in the range of 0.03mg/L– 0.94mg/L. Chromium concentration in all sachet brands were above the WHO standard while zinc was within the acceptable range. Cadmium and lead were below detectable limits (BDL). Conclusion: This study indicated that some of the sachet drinking water sold in the Hohoe Municipality is impure for human consumption. Inappropriate water purification procedures and improper handling of sachet water play a significant role in determining the overall quality of sachet drinking water.

Inducible deletion of the prostaglandin EP3 receptor in kidney tubules of male and female mice has no major effect on water homeostasis.

The prostaglandin E2 (PGE2) receptor EP3 has been detected in the thick ascending limb (TAL) and the collecting duct of the kidney, where its actions are proposed to inhibit water reabsorption. However, EP3 is also expressed in other cell types, including vascular endothelial cells. The aim here was to determine the contribution of EP3 in renal water handling in male and female adult mice by phenotyping a novel mouse model with doxycycline-dependent deletion of EP3 throughout the kidney tubule (EP3-/- mice). RNAscope demonstrated that EP3 was highly expressed in the cortical and medullary TAL of adult mice. Compared with controls EP3 mRNA expression was reduced by >80% in whole kidney (RT-qPCR) and nondetectable (RNAscope) in renal tubules of EP3-/- mice. Under basal conditions, there were no significant differences in control and EP3-/- mice of both sexes in food and water intake, body weight, urinary output, or clinical biochemistries. No differences were detectable between genotypes in handling of an acute water load or in their response to the vasopressin analog 1-deamino-8-d-arginine-vasopressin (dDAVP). No differences in water handling were observed when PGE2 production was enhanced using 1% NaCl load. Expression of proteins involved in kidney water handling was not different between genotypes. This study demonstrates that renal tubular EP3 is not essential for body fluid homeostasis in males or females, even when PGE2 levels are high. The mouse model is a novel tool for examining the role of EP3 in kidney function independently of potential developmental abnormalities or systemic effects.NEW & NOTEWORTHY The prostanoid EP3 receptor is proposed to play a key role in the kidney tubule and antagonize the effects of vasopressin on aquaporin-mediated water reabsorption. Here, we phenotyped a kidney tubule-specific inducible knockout mouse model of the EP3 receptor. Our major finding is that, even under physiological stress, tubular EP3 plays no detectable role in renal water or solute handling. This suggests that other EP receptors must be important for renal salt and water handling.

Decontamination of patient bathroom surfaces with 405 nm violet-blue light irradiation in a real-life setting

Irradiation with violet-blue light (VBL), in the spectrum of 405-450 nm, has been reported to be effective against pathogenic bacteria. The aim of the present study was to investigate if VBL irradiation could reduce the level of surface contamination at seven shared patient's bathrooms in two wards at a hospital in Sweden. Repeated sampling of five separate surfaces (door handle, tap water handle, floor, toilet seat and toilet armrest) was performed in the bathrooms where 405 nm light-emitting diode spotlights had been installed. A prospective study with a cross-over design was carried out, which included two study periods, first with the spotlights either switched on or off and a second study period with the opposite spotlight status. In total, 665 surface samples were collected during the study (133 samples per surface). Bacterial growth were found in 84 % of all samples. The most common findings were CoNS and Bacillus spp. The median cfu/cm2 was 15 (IQR 5-40) for all surfaces. In our main outcome, mean cfu/cm2 of all surfaces in a bathroom, no difference was observed with or without VBL. Clean surfaces (<5 cfu/cm2) were more commonly observed in bathrooms with VBL, also when controlling for confounding factors. No difference was observed in number of heavily contaminated surfaces. We could not safely demonstrate an additive effect on bacterial surface levels when adding VBL to routine cleaning in shared patient bathrooms.

Saprolegniosis in aquaculture and how to control it?

AbstractSaprolegniosis, also called water mould, induces a cotton or wool‐like white growth on fish skin. It can kill fish at all stages of life, from eggs to adults. It is caused by oomycetes from the genus Saprolegnia and causes fish mortality and huge financial losses to fish farms and hatcheries. Saprolegnia species are endemic and ubiquitous in all freshwater habitats around the world. The exposing factors for saprolegniosis are still largely unknown, but stressors such as temperature shocks, poor water quality, handling and high fish density have been associated with outbreaks. For decades, malachite green was the most effective treatment against Saprolegnia infection, but it has been banned due to its carcinogenic and toxic effects. This has forced farmers to use alternative disinfection methods against Saprolegnia infection, such as hydrogen peroxide, formalin, Bronopol, NaCl, acetic acid and ozone, although many may have safety concerns or are impractical to use. This has led to the investigation of plant‐based compounds with antifungal and antibacterial properties against saprolegniosis. These include extracts of certain herbs, onion, garlic, extracts of the plant Chrysanthemum, essential oils of Eryngium campestre, Mentha piperita, Cuminum cyminum and Thymus linearis, which include a variety of phenolic compounds and fatty acids with antifungal properties. This review combines the current knowledge regarding the predisposing factors to Saprolegnia infections and current methods to prevent and treat them, including those under further research. Thus far, many compounds have been tested and studied, but an effective, suitable and safe compound to treat Saprolegnia infection remains to be found.

Pelatihan Peningkatan PHBS dan Pengelolaan Air Siap Konsumsi pada Masyarakat Wilayah RW 006, Kelurahan Tanjung Duren Selatan

Water is crucial for human survival, serving both consumption needs and daily activities. However, water contamination often occurs when it is not managed and stored properly. Contaminated drinking water can pose health risks, causing various digestive diseases and even death, especially in children. Therefore, the management and storage of water require special attention. Indonesian communities, especially those in the RW 006, Tanjung Duren Selatan, are still limited in gathering clean water without proper water management for it to be made suitable for consumption. In response to this concern, a program was implemented to enhance awareness and empower the residents of RW 006, Tanjung Duren Selatan, focusing on improving environmental sanitation and the effective management of safe drinking water. The activities took place at the secretariat office of RW 006, Tanjung Duren Selatan, on Friday, November 10, 2023, from 08:30 to 10:15 AM. A total of 25 participants filled out attendance and completed pre-test questionnaires. Participants were then provided with education and training by the team on environmental sanitation, Community-Based Total Sanitation (STMB), proper management of household waste, and the handling of water intended for consumption. The post-test results showed an improvement in participants' knowledge and understanding regarding the enhancement of environmental sanitation and the management of water ready for consumption in households. It is hoped that participants will serve as links in communication and educators within the local community, ultimately contributing to improved sanitation and an enhanced quality of life.

Sex-dependent polymorphism in urinary output is reversed upon deletion of exchange protein directly activated by cAMP (Epac)

It is well-described that there are notable sex-dependent differences in urinary production with females having a smaller volume and greater urinary concentrating ability. Apart from contribution of the androgenic inputs, the underlying signaling intermediates remain largely unexplored. We previously showed that exchange protein directly activated by cAMP (Epac) is a critical regulator of water-solute transport in the proximal tubule and collecting duct. Deletion of either Epac1 or Epac2 isoforms increases urinary output and Na+ excretion. Here, we used metabolic cage balance studies to test whether Epac signaling mediates sex-dependent differences in urinary production. We found that concomitant deletion of Epac1&amp;2 moderately increases 24h urinary volume by 38% (from 1.82+/-0.13 to 2.52+/-0.21 ml) in males, but drastically augment urinary production in females by 320% (from 1.39+/-0.10 to 4.45+/-0.37 ml). This was associated with only a mild though significant reduction in urinary osmolarity in males by 35%, whereas urine osmolarity was markedly decreased from 2511+/-5 to 977+/-60 mOsm in females. Consistently, plasma osmolarity was not different in EpacWT versus Epac1&amp;2−/− males, but became significantly more hypertonic in Epac1&amp;2−/− females. We further determine the functional consequences of impaired Epac cascade on fluid reabsorption in the proximal tubule and collecting duct in males and females. Deletion of Epac1 and Epac2 decreases NHE-3 expression in the proximal tubule in an additive manner. In addition, Na+/H+-dependent recovery after acidification was drastically reduced in freshly isolated split-opened proximal tubules from Epac1&amp;2−/− mice when compared to EpacWT. Interestingly, the reduction of NHE-3 expression was more pronounced in Epac1&amp;2−/− females (by 89%) than in males (by 59%). Immunofluorescence confocal images revealed much more diffuse intracellular distribution of AQP2 water channel in Epac1&amp;2−/− females when compared to males. Furthermore, osmotically-driven water influx was reduced in principal cells within split-opened collecting ducts of Epac1&amp;2−/− females but not males, when compared to respective EpacWT. In summary, our results reveal a substantially greater role of Epac signaling in renal water handling in females than in males. Interestingly, Epac1&amp;2 deletion leads to a reversed pattern of sexual dimorphism in urinary production with females excreting larger volumes of hypotonic urine than males. This research was supported by NIH-NIDDK DK117865, DK119170, AHA EIA35260097 (to O. Pochynyuk). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Point-of-care circulating cathodic antigen positivity and associated factors in school children one year after mass praziquantel administration in an endemic district in Ghana

BackgroundMass drug administration of praziquantel is expected to reduce Schistosome carriage in treated children in endemic communities. However, the effectiveness of this annual exercise has not been assessed in Ghana. Therefore, this study aimed to detect viable Schistosoma mansoni infection using point-of-care circulating cathodic antigen (POC-CCA) positivity as proxy and associated factors in children previously treated with praziquantel in an endemic municipality in Ghana. Materials and methodsThis cross-sectional study was done in the Assin Central municipality in the Central Region of Ghana. School children, less than 16 years of age, treated with 40 mg/kg of praziquantel (treatment period: February–March 2019), provided early morning urine (∼40 mL) and stool (∼4 g) samples. Immediately, POC-CCA (ICT International, South Africa) was done, while S. mansoni ova were detected in formalin fixed samples using microscopy later. Additionally, participant's socio-demographic information and factors associated with S, mansoni infection transmission were collected from each child. ResultsA total of 520 children participated in the study (males-51.9%, majority age range [9–11 years, 34.4%]). Overall, 244 (46.9%) were positive for urinary CCA with no S. mansoni detected by microscopy. POC-CCA positivity was higher in females (48.4%), children with 2–3 siblings (49.3%), children aged 6–8-year range (55.4%) and residents of Brofoyedur (52%). However, age (x2 = 16.1, p = 0.0003) and town of residence (x2 = 11.7, p = 0.019) associated with CCA positivity. Further, location of water body (x2 = 16.4, p = 0.008), frequency of water contact (x2 = 12.3, p = 0.015) and handling of the Biomphalaria intermediate host (x2 = 5.1, p = 0.024) associated with POC-CCA outcome. ConclusionAbout 47% of the school children were positive for CCA, one year after mass praziquantel administration in the Assin Central municipality. Varied factors associated with the post-praziquantel administration POC-CCA positivity. This study should be replicated in other endemic areas to identify groups at risk of parasite persistence or reinfection to inform modification of control and preventive measures.

Regulation of the water channel aquaporin-2 by cullin E3 ubiquitin ligases.

Aquaporin 2 (AQP2) is a vasopressin (VP)-regulated water channel in the renal collecting duct. Phosphorylation and ubiquitylation of AQP2 play an essential role in controlling the cellular abundance of AQP2 and its accumulation on the plasma membrane in response to VP. Cullin-RING ubiquitin ligases (CRLs) are multisubunit E3 ligases involved in ubiquitylation and degradation of their target proteins, eight of which are expressed in the collecting duct. Here, we used an established cell model of the collecting duct (mpkCCD14 cells) to study the role of cullins in modulating AQP2. Western blotting identified Cul-1 to Cul-5 in mpkCCD14 cells. Treatment of cells for 4 h with a pan-cullin inhibitor (MLN4924) decreased AQP2 abundance, prevented a VP-induced reduction in AQP2 Ser261 phosphorylation, and attenuated VP-induced plasma membrane accumulation of AQP2 relative to the vehicle. AQP2 ubiquitylation levels were significantly higher after MLN4924 treatment compared with controls, and they remained higher despite VP treatment. Cullin inhibition increased ERK1/2 activity, a kinase that regulates AQP2 Ser261 phosphorylation, and VP-induced reductions in ERK1/2 phosphorylation were absent during MLN4924 treatment. Furthermore, the greater Ser261 phosphorylation and reduction in AQP2 abundance during MLN4924 treatment were attenuated during ERK1/2 inhibition. MLN4924 increased intracellular calcium levels via calcium release-activated calcium channels, inhibition of which abolished MLN4924 effects on Ser261 phosphorylation and AQP2 abundance. In conclusion, CRLs play a vital role in mediating some of the effects of VP to increase AQP2 plasma membrane accumulation and AQP2 abundance. Whether modulation of cullin activity can contribute to body water homeostasis requires further studies.NEW & NOTEWORTHY Aquaporin 2 (AQP2) is essential for body water homeostasis and is regulated by the antidiuretic hormone vasopressin. The posttranslational modification ubiquitylation is a key regulator of AQP2 abundance and plasma membrane localization. Here we demonstrate that cullin-RING E3 ligases play a vital role in mediating some of the effects of vasopressin to increase AQP2 abundance and plasma membrane accumulation. The results suggest that manipulating cullin activity could be a novel strategy to alter kidney water handling.

Influence of Organic Matter from Native Fish on the Antimicrobial Efficacy of Sodium Hypochlorite (NaClO) in Reducing Salmonella spp. Population

Salmonella spp. is not part of the fish microbiota, being introduced through contaminated water or improper handling. In slaughterhouses, five parts per million (ppm) of free chlorine is recommended in the washing step to eliminate this pathogen. However, Salmonella spp. is still detected in fish processing plants due to persistent contamination as a result of chlorine–organic matter interactions that reduce chlorine effectiveness. Therefore, this study aimed to test whether organic matter contained in culture media and fish washes interferes with the efficacy of chlorine at 2 and 5 ppm, and what is the time of action required to inactivate ATCC and wild strains of S. typhimurium. For this, the elimination or survival of these strains was investigated when exposed to chlorinated solution for different durations (0, 5, 30, 60, 90 and 120 min) in culture medium, 0.85% saline solution and fish wash (in natura and sterilized). The results showed that the use of 5 ppm of free chlorine is efficient, even when the chlorine remains in contact with the organic matter (washed from the fish), as it reduced the bacterial population by ~5 log log10 CFU/mL of Salmonella spp., showing that this reduction was due to interactions, as long as the chlorine action time was 30 min.

NRF2 in kidney physiology and disease.

The role of NRF2 in kidney biology has received considerable interest over the past decade. NRF2 transcriptionally controls genes responsible for cellular protection against oxidative and electrophilic stress and has anti-inflammatory functions. NRF2 is expressed throughout the kidney and plays a role in salt and water handling. In disease, animal studies show that NRF2 protects against tubulointerstitial damage and reduces interstitial fibrosis and tubular atrophy, and may slow progression of polycystic kidney disease. However, the role of NRF2 in proteinuric glomerular diseases is controversial. Although the NRF2 inducer, bardoxolone methyl (CDDO-Me), increases glomerular filtration rate in humans, it has not been shown to slow disease progression in diabetic kidney disease and Alport syndrome. Furthermore, bardoxolone methyl was associated with negative effects on fluid retention, proteinuria, and blood pressure. Several animal studies replicate findings of worsened proteinuria and a more rapid progression of kidney disease, although considerable controversy exists. It is clear that further study is needed to better understand the effects of NRF2 in the kidney. This review summarizes the available data to clarify the promise and risks associated with targeting NRF2 activity in the kidney.

Progression of renal damage and tubular regeneration in pregnant and non-pregnant adult female rats inoculated with a sublethal dose of Shiga toxin 2

BackgroundShiga toxin-producing Escherichia coli is the main cause of post-diarrheal hemolytic uremic syndrome (HUS) which produces acute kidney injury mainly in children, although it can also affect adults. The kidneys are the organs most affected by Shiga toxin type 2 (Stx2) in patients with HUS. However, previous studies in pregnant rats showed that a sublethal dose of Stx2 causes severe damage in the uteroplacental unit and induces abortion, whereas produces mild to moderate renal damage. The aim of the present work was to study the progression of renal injury caused by a sublethal dose of Stx2, as well as renal recovery, in pregnant and non-pregnant rats, and to investigate whether pregnancy physiology may affect renal damage progression mediated by Stx2. MethodsRenal function and histopathology was evaluated in pregnant rats intraperitoneally injected with a sublethal dose of Stx2 (0.5 ng/g bwt) at the early stage of gestation (day 8 of gestation), and results in these rats were compared over time with those observed in non-pregnant female rats injected with the same Stx2 dose. Hence, progression of cell proliferation and dedifferentiation in renal tubular epithelia was also investigated. ResultsThe sublethal dose of Stx2 induced abortion in pregnant rats as well as a significant more extended functional and histological renal injury in non-pregnant rats than in pregnant rats. Stx2 also caused decreased ability to concentrate urine in non-pregnant rats compared to their controls. However, renal water handling in pregnant rats was not altered by Stx2, and was significantly different than in non-pregnant rats. The greatest renal injury in both pregnant and non-pregnant rats was observed at 4 days post-Stx2 injection, and coincided with a significant increase in tubular epithelial proliferation. Expression of mesenchymal marker vimentin in tubular epithelia was consistent with the level of tubular damage, being higher in non-pregnant rats than in pregnant rats. Recovery from Stx2-induced kidney injury was faster in pregnant rats than in non-pregnant rats. ConclusionsAdaptive mechanisms developed during pregnancy such as changes in water handle and renal hemodynamic may contribute to lessen the Stx2-induced renal injury, perhaps at the expense of fetal loss.

Impacts of sunlight exposure on physicochemical parameters, potential toxic metals, and microbial characteristics of sachet drinking water sold in Calabar metropolis, Nigeria

Poor handling of potable water is a well-known route of contamination. Despite this, Nigeria’s most consumed packaged potable water called “sachet” or “pure water” is still poorly handled with long hours of exposure to sunlight which may affect its quality. This study examined the potential deterioration of the sachet water quality (potential toxic metals and bacteriological), and the health implication posed by long-time exposure to sunlight. Collected water samples were subjected to physiochemical analysis, metal analysis, risk assessment, and microbiological examination. Three sachet water brands (n = 4 bags per brand) exposed to sunlight daily for 14, 28, and 42 days were analysed for potentially toxic metals, and health risk assessments (Average daily dose-ADD, hazard quotient-HQ, hazard index-HI, and carcinogenic risk-CR). The physicochemical, and microbiological (total heterotrophic bacteria count-THBC, and total coliform count-TCC) parameters were equally analysed using the Kirby Bauer and pour plate technique. In all brands, the levels of physicochemical parameters (except pH), and potential toxic metals were comparatively higher than the control in an exposure time-dependent fashion. Furthermore, all the exposed samples failed to meet the safety limits of the WHO, and national standards (NAFDAC and NDSWQ) for drinking water. Among the metals, zinc was the most ingested metal in all the brands. The ADD, HQ, and HI evaluations revealed that consuming the exposed water could lead to higher accumulation of Cr, Cd, Pb, As, and Ni in the body following exposure. The CR of Cr, As, and Ni after exposure to sunlight were > than the safe value (10–4), implying the likelihood of cancer after over 60 years. Microbial counts increased with the length of exposure, and all the isolates showed pathogenicity and multidrug resistance. The potential health risk inherent in sachet water after exposure to sunlight has significant health implications for consumers.

First uninterrupted sleep periodin children and adolescents with nocturnal enuresis: Added value in diagnosis and follow-up during therapy.

The first uninterrupted sleep period (FUSP, time up to the first episode of enuresis/nocturia after falling asleep) is a frequently investigated parameter in adults with nocturia, as it correlates with quality of life. However, it has not been included in pediatric enuresis studies. Investigate FUSP, circadian renal water and sodium handling, as well as sleep quality before and after desmopressin therapy in enuresis. We conducted a post hoc analysis of a prospective study in 30 treatment-naïve children with enuresis who underwent avideo-polysomnographyand a 24-h urine concentration profile before and after 6 months of desmopressin therapy. We analyzed FUSP, periodic limb movements in sleep(PLMS), and arousal indexes and their correlations with the urinary parameters. Sixteen children with a mean age of 10.9 ± 3.1 years had full registrations and were included in this subanalysis. After therapy, FUSP was significantly longer (p < 0.001), and the PLMS index was lower (p = 0.023). Significant differences in the circadian rhythm of diuresis (night/day diuresis, p = 0.041), nocturnal urinary osmolality (p = 0.009), and creatinine (p = 0.001) were found, demonstrating the increase of urinary concentration overnight by desmopressin, as well as a significant antidiuretic effect (diuresis [p = 0.013] and diuresis rate (p = 0.008). There was no correlation between the difference of FUSP, PLMS index, and urinary parameters. Nevertheless, despite this study being underpowered, there are indications of a correlation between nocturnal diuresis and diuresis rate. Our results support the need for further research regarding FUSP in children with enuresis, in accordance with nocturia studies in adults, as this parameter could be valuable in the follow-up and evaluation of therapeutic strategies for enuresis.

Brief early life angiotensin-converting enzyme inhibition attenuates the diuretic response to saline loading in sheep with solitary functioning kidney.

A solitary functioning kidney (SFK) from birth predisposes to hypertension and kidney dysfunction, and this may be associated with impaired fluid and sodium homeostasis. Brief and early angiotensin converting enzyme inhibition (ACEi) in a sheep model of SFK delays onset of kidney dysfunction. We hypothesized that modulation of the renin angiotensin system via brief postnatal ACEi in SFK would reprogram renal sodium and water handling. Here, blood pressure (BP), kidney haemodynamics and kidney excretory function were examined in response to an isotonic saline load (0.13 ml/kg/min; 180 minutes) at 20 months of age in SFK (fetal unilateral nephrectomy at 100 days gestation; term 150 days), sham and SFK+ACEi sheep (ACEi in SFK 4-8 weeks of age). Basal BP was higher in SFK than sham ( 13 mm Hg), and similar between SFK and SFK+ACEi groups. Saline loading caused a small increase in BP ( 3-4 mm Hg) the first two hours in SFK and sham sheep but not SFK+ACEi sheep. Glomerular filtration rate did not change in response to saline loading. Total sodium excretion was similar between groups. Total urine excretion was similar between SFK and sham animals but was 40% less in SFK+ACEi animals compared to SFK animals. In conclusion, this study indicates that water homeostasis in response to a physiological challenge is attenuated at 20 months of age by brief early life ACEi in SFK. Further studies are required to determine if ACEi in early life in children with SFK could compromise fluid homeostasis later in life.

Effect of fluid replacement with green tea on body fluid balance and renal responses under mild thermal hypohydration: a randomized crossover study.

Maintaining an appropriate hydration level by ingesting fluid in a hot environment is a measure to prevent heat-related illness. Caffeine-containing beverages, including green tea (GT), have been avoided as inappropriate rehydration beverages to prevent heat-related illness because caffeine has been assumed to exert diuretic/natriuretic action. However, the influence of caffeine intake on urine output in dehydrated individuals is not well documented. The aim of the present study was to examine the effect of fluid replacement with GT on body fluid balance and renal water and electrolyte handling in mildly dehydrated individuals. Subjects were dehydrated by performing three bouts of stepping exercise for 20min separated by 10min of rest. They were asked to ingest an amount of water (H2O), GT, or caffeinated H2O (20mg/100ml; Caf-H2O) that was equal to the volume of fluid loss during the dehydration protocol; fluid balance was measured for 2h after fluid ingestion. The dehydration protocol induced hypohydration by ~ 10g/kg body weight (~ 1% of body weight). Fluid balance 2h after fluid ingestion was significantly less negative in all trials, and the fluid retention ratio was 52.2 ± 4.2% with H2O, 51.0 ± 5.0% with GT, and 47.9 ± 6.2% with Caf-H2O; those values did not differ among the trials. After rehydration, urine output, urine osmolality, and urinary excretions of osmotically active substances, sodium, potassium and chloride were not different among the trials. The data indicate that ingestion of GT or an equivalent caffeine amount does not worsen the hydration level 2h after ingestion and can be effective in reducing the negative fluid balance for acute recovery from mild hypohydration. ISRCTN53057185; retrospectively registered.

Drinking water quality and associated factors in Bahir Dar City and the surrounding rural areas, Northwest Ethiopia: a community-based cross-sectional study

Abstract In low-income countries like Ethiopia, waterborne illnesses have posed serious public health problems. This study aimed to evaluate drinking water quality (DWQ) and associated factors in Bahir Dar City and the surrounding rural areas in northwest Ethiopia. A cross-sectional study was conducted from January to June 2022 to determine coliform counts and basic physicochemical parameters from the drinking water samples (DWS) collected from urban, peri-urban, and rural sites. A total of 180 DWS were collected from water collection points and households' containers. Potentially pathogenic bacteria were also isolated from fecal coliform (FC)-positive samples and their antibiotic susceptibility profiles were determined. Moreover, the risk factors associated with water quality were assessed. The water quality test results were evaluated against the WHO guidelines for DWQ. Based on the results of this study, only 16.7 and 73.88% of samples met the standards for total coliform and FC, respectively. Moreover, 95.4 and 43% of the isolated bacteria were resistant at least to one of the commonly used antibiotics and multidrug-resistant, respectively. Educating the public on proper drinking water handling, appropriate treatment, and waterline maintenance are needed to safeguard the community from waterborne diseases.

Aquaporin water channels: roles beyond renal water handling.

Aquaporin (AQP) water channels are pivotal to renal water handling and therefore in the regulation of body water homeostasis. However, beyond the kidney, AQPs facilitate water reabsorption and secretion in other cells and tissues, including sweat and salivary glands and the gastrointestinal tract. A growing body of evidence has also revealed that AQPs not only facilitate the transport of water but also the transport of several small molecules and gases such as glycerol, H2O2, ions and CO2. Moreover, AQPs are increasingly understood to contribute to various cellular processes, including cellular migration, adhesion and polarity, and to act upstream of several intracellular and intercellular signalling pathways to regulate processes such as cell proliferation, apoptosis and cell invasiveness. Of note, several AQPs are highly expressed in multiple cancers, where their expression can correlate with the spread of cancerous cells to lymph nodes and alter the response of cancers to conventional chemotherapeutics. These data suggest that AQPs have diverse roles in various homeostatic and physiological systems and may be exploited for prognostics and therapeutic interventions.

Spatial and temporal water chemistry variations of hydraulic fracturing flowback and produced waters from the Duvernay Formation

Chemical characterization of hydraulic fracturing (HF) flowback and produced water (FPW) is important to the environmental sustainability of HF operations. In this research, we analyzed and compared HF FPW samples from different well locations as well as FPW samples from a single well at different stages of FPW production in the Duvernay Formation using a suite of analytical techniques and statistical methods. The results provide vital information to assess the reusability of FPW and support the choice of water handling, treatment, or disposal options. Additionally, this work contributes to a more complete understanding of regional FPW chemical composition and has the potential to provide guidance on best practices for future applications of HF fluid additives. While reuse of FPW is desirable, it is not always feasible. In these scenarios, the transportation of FPW offsite for treatment and/or disposal increases the risk of spills to near-surface environments. This work provides data to aid spill clean-up efforts and to determine the environmental fate of FPW contaminants. Overall, the information presented in this work may be used to provide economic benefits to the oil and gas sector by increasing FPW reuse that will directly decrease wastewater disposal costs and reduce environmental impacts of HF operations by decreasing the volume of used surface water and the risk of FPW surface spills.

Differences in the urinary metabolome and proteome between wet and dry nights in children with monosymptomatic nocturnal enuresis and nocturnal polyuria.

Nocturnal enuresis (NE) is a common disease with multiple pathogenic mechanisms. This study aimed to compare levels of metabolites and proteins between wet and dry nights in urine samples from children with monosymptomatic NE (MNE). Ten boys with MNE and nocturnal polyuria (age: 7.6 ± 1.3 years) collected their total nighttime urine production during a wet and a dry night. Untargeted metabolomics and proteomics were performed on the urine samples by liquid chromatography coupled with high-mass accuracy tandem mass spectrometry (LC-MS/MS). On wet nights, we found reduced urine osmolality (P = 0.025) and increased excretion of urinary potassium and sodium by a factor of, respectively, 2.1 (P = 0.038) and 1.9 (P = 0.19) compared with dry nights. LC-MS identified 59 metabolites and 84 proteins with significantly different levels between wet and dry nights (fold change (FC) < 0.67 or > 1.5, P < 0.05). Some compounds were validated by different methodologies. During wet nights, levels of compounds related to oxidative stress and blood pressure, including adrenalin, were increased. We found reduced levels of aquaporin-2 on wet nights. The FCs in the 59 metabolites were positively correlated to the FCs in the same metabolites identified in urine samples obtained during the evening preceding wet and dry nights. Oxidative stress, which in the literature has been associated with nocturia and disturbances in sleep, might be increased during wet nights in children with MNE. We further found evidence of increased sympathetic activity. The mechanisms related to having wet nights in children with MNE seem complex, and both free water and solute handling appear to be important. A higher resolution version of the Graphical abstract is available as Supplementary information.

Preparing New Ceramic Membranes from Syrian Zeolite Coated with Silver Nanoparticles to Treatment Wells Water

As a result of the exacerbation of the problem of water pollution, research was directed towards studying the treatment using ceramic membranes, which proved to be highly effective in treating all water sources. The research aims to study the possibility of preparing a new type of ceramic membranes from Syrian zeolite that was not previously used in this field. In this research, ceramic membranes were prepared from Syrian raw zeolite in several stages. Zeolite sample was characterized, grinded, mixed with boric acid, pressed to form desks, treated thermally according to experiment program, finally coated with silver nanoparticles. Specifications of prepared membranes were determined according to reference methods, effectiveness of prepared membranes were tested in well water handling, that water sample was filtrated through prepared membranes, and then it type MAC, so removal degree was 100%, While removal degree was 97% for bacterial strains on Agar with type PCA, 93% on Agar with type PDA which were conformed to Syrian standard /45 /2007. Specifications of prepared membranes were determined according to reference methods, effectiveness of prepared membranes were tested in well water handling, that water sample was filtrated through prepared membranes, then it was Characterized after treatment. Results showed that prepared zeolite membranes were high effectiveness through decrease chemical and microbial pollutants which were conformed to Syrian standard /45 /2007