Critical review on toxic contaminants in surface water ecosystem: sources, monitoring, and its impact on human health.

Surface water pollution is a critical and urgent global issue that demands immediate attention. Surface water plays a crucial role in supporting and sustaining life on the earth, but unfortunately, till now, we have less understanding of its spatial and temporal dynamics of discharge and storage variations at a global level. The contamination of surface water arises from various sources, classified into point and non-point sources. Point sources are specific, identifiable origins of pollution that release pollutants directly into water bodies through pipes or channels, allowing for easier identification and management, e.g., industrial discharges, sewage treatment plants, and landfills. However, non-point sources originate from widespread activities across expansive areas and present challenges due to its diffuse nature and multiple pathways of contamination, e.g., agricultural runoff, urban storm water runoff, and atmospheric deposition. Excessive accumulation of heavy metals, persistent organic pollutants, pesticides, chlorination by-products, pharmaceutical products in surface water through different pathways threatens food quality and safety. As a result, there is an urgent need for developing and designing new tools for identifying and quantifying various environmental contaminants. In this context, chemical and biological sensors emerge as fascinating devices well-suited for various environmental applications. Numerous chemical and biological sensors, encompassing electrochemical, magnetic, microfluidic, and biosensors, have recently been invented by hydrological scientists for the detection of water pollutants. Furthermore, surface water contaminants are monitored through different sensors, proving their harmful effects on human health.

Endogenous ZAP affects Zika virus RNA interactome.

One of the most recent advances in the analysis of viral RNA-cellular protein interactions is the Comprehensive Identification of RNA-binding Proteins by Mass Spectrometry (ChIRP-MS). Here, we used ChIRP-MS in mock-infected and Zika-infected wild-type cells and cells knockout for the zinc finger CCCH-type antiviral protein 1 (ZAP). We characterized 'ZAP-independent' and 'ZAP-dependent' cellular protein interactomes associated with flavivirus RNA and found that ZAP affects cellular proteins associated with Zika virus RNA. The ZAP-dependent interactome identified with ChIRP-MS provides potential ZAP co-factors for antiviral activity against Zika virus and possibly other viruses. Identifying the full spectrum of ZAP co-factors and mechanisms of how they act will be critical to understanding the ZAP antiviral system and may contribute to the development of antivirals.

Randomised controlled trial of tourniquet associated pain generated in lower limb after exsanguination by Esmarch bandage versus limb elevation.

BACKGROUND: Tourniquets are common adjuncts in the operating theatre but can be associated with post-operative pain. This study was designed to compare what effect pre-tourniquet Esmarch bandage exsanguination has on pain, compared to pre-tourniquet exsanguination by elevation alone. METHODS: 52 volunteers (104 lower limbs) were included in this study with each volunteer acting as their own matched control. The primary outcome was patient reported pain, measured in both legs simultaneously using area under curve. Secondary outcomes were pain score during inflation and deflation, cumulative pain score, duration of recovery and blood pressure during testing. RESULTS: Pain after Esmarch was superior to elevation as measured by area under pain curve (68.9 SD 26.1 vs 77.2 SD 27.3, p = 0.0010), independent of leg dominance. Cumulative pain scores demonstrated the same superiority after inflation (50.7 SD 17.1 vs 52.9 SD 17.0, p = 0.026) but not after deflation (p = 0.59). Blood pressure was not significantly different. Time to full recovery of the lower limb was the same for both groups-7.6 min (SD 2.1 min, p = 0.80). CONCLUSION: Previous studies describe a positive effect on pain when Esmarch bandage was used prior to tourniquet inflation for upper limb. Our findings suggest the same benefit from Esmarch when it was used on lower limbs-particularly during inflation of tourniquet. In addition to pain profiles, surgeon preference and patient factors need to be considered when deciding between elevation and Esmarch bandage.

Soil-mustard revitalization via rice husk ash, a promising soil amendment material for sustainable management of heavy metal contamination in tropical ecosystem.

Prolonged wastewater irrigation in agriculture has led to the accumulation of heavy metals in soil, endangering both the soil quality and food safety, thereby posing a potential threat to human health through the consumption of contaminated crops. The present study aimed to enhance the yield of mustard (Brassica juncea L. cv. Varuna and NRCHB 101) plants and stabilize heavy metals (Cd, Cr, Ni, Cu, and Zn) in wastewater-irrigated soil using rice husk ash (RHA), rice mill by-product, collected from Chandauli region of Eastern Uttar Pradesh, India. Results demonstrated significant improvements in growth, biomass, physiology, and yield of mustard plant with increasing RHA application in wastewater irrigated soil (p ≤ 0.05). Heavy metal accumulation in different parts of mustard plants decreased as RHA application rate increased. Applying RHA at 2% in soil proved to be most effective in reducing Cd, Cr, Ni, Cu, and Zn accumulation in seeds by 29%, 29.6%, 23.1%, 21.3% and 20.1%, respectively in Varuna and 30.1%, 21.4%, 11.1%, 12.1%, and 28.5%, respectively in NRCHB 101cultivars. The present findings showed that RHA amendment in wastewater irrigated soil had reduced bioaccumulation of Cd, Cr, Ni, Cu, and Zn and consequently their toxicity in cultivated mustard plants. A novel application of RHA is unveiled in this research, offering a promising solution to promote sustainable agriculture and to reduce heavy metal associated health risks within the soil-mustard system.

Screening of mustard cultivars for phytoremediation of heavy metals contamination in wastewater irrigated soil systems.

The mustard (Brassica juncea L.) plant is a well-known and widely accepted hyper-accumulator of heavy metals. The genetic makeup of mustard's cultivars may significantly impact their phytoremediation capabilities. The present study aimed to investigate the growth performance, yield attributes, and heavy metal accumulation potential of B. juncea cv. Varuna, NRCHB 101, RH 749, Giriraj, and Kranti, cultivated in soil irrigated with wastewater (EPS) and bore-well water (MPS). EPS contributed more Cr, Cd, Cu, Zn, and Ni to tested mustard cultivars than the MPS. EPS reduced morphological, biochemical, physiological, and yield attributes of tested mustard cultivars significantly (p < 0.05) than the MPS. Among the tested cultivars of mustard plants, Varuna had the highest heavy metal load with the lowest harvest index (35.8 and 0.21, respectively). Whereas NRCHB 101 showed the lowest heavy metal load with the highest harvest index (26.9 and 0.43, respectively). The present study suggests that B. juncea cv. Varuna and NRCHB 101 could be used for the phytoextraction of heavy metals and reducing their contamination in food chain, respectively in wastewater irrigated areas of peri-urban India. The outcomes of the present study can also be utilized to develop a management strategy for sustainable agriculture in heavy metal polluted areas resulting from long-term wastewater irrigation.

Repurposing dimethyl fumarate as an antiepileptogenic and disease-modifying treatment for drug-resistant epilepsy.

BACKGROUND: Epilepsy affects over 65 million people worldwide and significantly burdens patients, caregivers, and society. Drug-resistant epilepsy occurs in approximately 30% of patients and growing evidence indicates that oxidative stress contributes to the development of such epilepsies. Activation of the Nrf2 pathway, which is involved in cellular defense, offers a potential strategy for reducing oxidative stress and epilepsy treatment. Dimethyl fumarate (DMF), an Nrf2 activator, exhibits antioxidant and anti-inflammatory effects and is used to treat multiple sclerosis. METHODS: The expression of Nrf2 and its related genes in vehicle or DMF treated rats were determined via RT-PCR and Western blot analysis. Neuronal cell death was evaluated by immunohistochemical staining. The effects of DMF in preventing the onset of epilepsy and modifying the disease were investigated in the kainic acid-induced status epilepticus model of temporal lobe epilepsy in rats. The open field, elevated plus maze and T-Maze spontaneous alteration tests were used for behavioral assessments. RESULTS: We demonstrate that administration of DMF following status epilepticus increased Nrf2 activity, attenuated status epilepticus-induced neuronal cell death, and decreased seizure frequency and the total number of seizures compared to vehicle-treated animals. Moreover, DMF treatment reversed epilepsy-induced behavioral deficits in the treated rats. Moreover, DMF treatment even when initiated well after the diagnosis of epilepsy, reduced symptomatic seizures long after the drug was eliminated from the body. CONCLUSIONS: Taken together, these findings suggest that DMF, through the activation of Nrf2, has the potential to serve as a therapeutic target for preventing epileptogenesis and modifying epilepsy.

Asian Zika virus can acquire generic African-lineage mutations during in utero infection.

The Zika virus 2015 epidemic showed an unusual phenotype for human flaviviruses, specifically fetal infection. We previously showed that in utero inoculation with the Asian Zika virus isolated from the human sample causes persistent infection in porcine fetuses. Here, we characterized the evolution of the Asian Zika virus in the fetal brain and placenta. Interestingly, the Asian Zika virus acquired generic African lineage K101R (A408G) and R1609 K (G4932A) mutations during in utero infection. Both African mutations were nonsynonymous and had a high frequency of nearly 100% in the fetal brain. Then, we synthetically generated the wild-type Asian variant and fetal brain-specific variant with generic African-lineage K101R and R1609 K mutations. In mosquito C6/36 cells, but not in human and pig cells, the fetal brain-specific variant showed higher virus loads compared to the Asian wild-type prototype. While in utero infection with both variants caused comparable virus loads in the placenta and amniotic fluids, fetuses injected with the fetal brain-specific variant had the trend to higher virus loads in lymph nodes. Also, introduced K101R and R1609 K mutations were stable and had high nearly 100% frequency at 28 days after in utero inoculation in both directly injected and trans-infected fetuses. These findings evoke concerns because Zika persists in pig herds and mosquitoes on farms in Mexico. It will be essential to identify how persistent in utero infection affects virus evolution and whether in utero-emerged Zika variants have the potential for shedding into the environment, more efficient transmission, and more aggressive infection phenotypes.

Hydrogen adsorption and diffusion through a two dimensional sheet of lithium: a first principles study.

Two-dimensional (2D) materials have shown promise as highly selective, ultrathin membranes to transport ions, and atomic and subatomic particles. They have also been regarded as potential hydrogen storage candidates due to their chemical stability and high specific surface area. However, most of these studies have been carried out with semiconducting 2D materials. With recent explorations towards the existence and stability of 2D metals, we explore the hydrogen adsorption and diffusion through a 2D metallic sheet of lithium. We report that in the lowest energy metallic configuration, the sheet is predicted to crystallize in a highly buckled honeycomb structure. We calculate the adsorption energy for the diffusion of hydrogen on various high symmetry sites in the lattice, and find that adsorption is energetically favoured. We study the minimum energy pathways for diffusion through the sheet and find that the lowest energy barriers exist for tunneling through the honeycomb ring. Our results would be of direct technological relevance to the applications of 2D metallic nanostructures as membranes for selective transport or towards storage.

Nrf2 is expressed more extensively in neurons than in astrocytes following an acute epileptic seizure in rats.

The modulation of the nuclear factor erythroid 2-like 2 (Nrf2) activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post-status epilepticus rat model; however, the spatiotemporal as well as cell type-specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the rats' cortex and the hippocampus up to 1 week following the induced seizure. We found that after a pentylenetetrazol-induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3 h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3 h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3-6 h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co-localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after the seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.

Nrf2 is predominantly expressed in hippocampal neurons in a rat model of temporal lobe epilepsy.

BACKGROUND: Drug resistance is a particular problem in patients with temporal lobe epilepsy, where seizures originate mainly from the hippocampus. Many of these epilepsies are acquired conditions following an insult to the brain such as a prolonged seizure. Such conditions are characterized by pathophysiological mechanisms including massive oxidative stress that synergistically mediate the secondary brain damage, contributing to the development of epilepsy. The transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged in recent years as an attractive therapeutic approach targeting to upregulate the antioxidative defenses in the cell, to ameliorate the oxidative stress-induced damage. Thus, it is important to understand the characteristics of Nrf2 activation during epileptogenesis and epilepsy. Here, we studied the temporal, regional, and cell-type specific expression of Nrf2 in the brain, in a rat model of temporal lobe epilepsy. RESULTS: Early after status-epilepticus, Nrf2 is mainly activated in the hippocampus and maintained during the whole period of epileptogenesis. Only transient expression of Nrf2 was observed in the cortex. Nevertheless, the expression of several Nrf2 antioxidant target genes was increased within 24 h after status-epilepticus in both the cortex and the hippocampus. We demonstrated that after status-epilepticus in rats, Nrf2 is predominantly expressed in neurons in the CA1 and CA3 regions of the hippocampus, and only astrocytes in the CA1 increase their Nrf2 expression. CONCLUSIONS: In conclusion, our data identify previously unrecognized spatial and cell-type dependent activation of Nrf2 during epilepsy development, highlighting the need for a time-controlled, and cell-type specific activation of the Nrf2 pathway for mediating anti-oxidant response after brain insult, to modify the development of epilepsy.

Carpet industry irrigational sources risk assessment: Heavy metal contaminated vegetables and cereal crops in northern India.

Wastewater is often discharged to natural water bodies through an open channel as well as used by marginal farmers to irrigate the agricultural fields, particularly in sub-urban areas of developing countries. In the present study, the samples of irrigation water, soil, vegetables (i.e., palak; Beta vulgaris L. var All green H1, radish; Raphanus sativus L., garlic; Allium sativum L., cabbage; Brassica oleracea L. var. capitata, brinjal; Solanum melongena L.) and crops (i.e., paddy; Oryza sativa L. and wheat; Triticum aestivum L.) were collected from the agricultural areas receiving untreated wastewater from a carpet industrial and residential areas since a decade. The contents of Cd, Cr, Cu, Ni, and Zn in the filtrates of water, soil, and crops were determined using an Atomic Absorption Spectrophotometer (Perkin-Elmer AAnalyst 800, USA). Daily intake, hazardous quotient and heavy metal pollution index were computed to assess the health risk associated with consumption of heavy metal contaminated crops. The mean concentrations of Cd and Zn in B. vulgaris (5.35 µg g-1 dw and 58.41 µg g-1 dw, respectively) and Cr, Cu, and Ni in grains of T. aestivum (16.02 µg g-1 dw, 27.97 µg g-1 dw and 40.74 µg g-1 dw, respectively) were found highest and had exceeded the Indian safety limit. Daily intake of Cu, Ni, and Cr via consumption of tested cereal crops was found higher than the vegetables. The health quotient revealed that health of local residents is more linked to vegetables than cereal crops. The present findings may be helpful to the policymakers and regulatory authorities to modify the existing policy of wastewater uses in the agriculture and disposal to the natural water bodies. The regular monitoring of heavy metals in the wastewater should also be ensured by the regulatory authorities for their safe disposal to natural water bodies/agriculture in order to reduce the human health risk associated with the degree of heavy metal contaminated suburban food systems.

Specific inhibition of NADPH oxidase 2 modifies chronic epilepsy.

Recent work by us and others has implicated NADPH oxidase (NOX) enzymes as main producers of reactive oxygen species (ROS) following a brain insult such as status epilepticus, contributing to neuronal damage and development of epilepsy. Although several NOX isoforms have been examined in the context of epilepsy, most attention has focused on NOX2. In this present study, we demonstrate the effect of gp91ds-tat, a specific competitive inhibitor of NOX2, in in vitro epileptiform activity model as well as in temporal lobe epilepsy (TLE) model in rats. We showed that in in vitro seizure model, gp91ds-tat modulated Ca2+ oscillation, prevented epileptiform activity-induced ROS generation, mitochondrial depolarization, and neuronal death. Administration of gp91ds-tat 1 h after kainic acid-induced status epilepticus significantly decreased the expression of NOX2, as well as the overall NOX activity in the cortex and the hippocampus. Finally, we showed that upon continuous intracerebroventricular administration to epileptic rats, gp91ds-tat significantly reduced the seizure frequency and the total number of seizures post-treatment compared to the scrambled peptide-treated animals. The results of the study suggest that NOX2 may have an important effect on modulation of epileptiform activity and has a critical role in mediating seizure-induced NOX activation, ROS generation and oxidative stress in the brain, and thus significantly contributes to development of epilepsy following a brain insult.

Phytochemical Screening, Quantification, FT-IR Analysis, and In Silico Characterization of Potential Bio-active Compounds Identified in HR-LC/MS Analysis of the Polyherbal Formulation from Northeast India.

Diabetes is a group of metabolic disorders characterized by elevated blood sugar levels, leading to many undesirable health consequences. There are many herbal formulations, traditionally used by the Northeast Indian population for disease management. These formulations require scientific validations to optimize their efficacy and increase their popularity. In this study, we attempt to scientifically validate a polyherbal formulation traditionally used for the management of diabetes through preliminary phytochemicals investigation, characterization of potential phytochemicals using Fourier transform infrared (FT-IR) spectroscopy, high-resolution liquid chromatography mass spectrometry (HR-LC/MS) analysis, and in silico characterization of physiochemical, drug-likeness, and pharmacokinetic properties of identified phytochemical compounds. Qualitative phytochemical screening of various extracts of the formulation confirmed the presence of alkaloids, phenols and tannins, flavonoids, fats, and oils. Phytochemical quantification of the various extracts showed that the highest total phenolic content is present in the ethanolic extract (35.61 ± 0.15 mg GAE/g), while the highest total flavonoid content is present in the chloroform extract (76.33 ± 2.96 mg QE/g) of the formulation. FT-IR spectroscopic analysis revealed various characteristic band values with various functional groups in the formulation extract such as amines, alcohol, fluoro compounds, phenol, alkane, alkene, and conjugated acid groups. HR-LC/MS analyses identified nearly 51 compounds including 9 small peptides and 42 potential phytochemical compounds. In silico SwissADME analysis of identified compounds revealed 25 potential compounds following Lipinski's rule and showing drug-like characteristics, and out of them, 16 compounds exhibited good oral bioavailability, as revealed in the bioavailability radar. The overall study showed that the presented polyherbal formulation is enriched with bio-active phytochemical compounds with good pharmaceutical values.

Spatial, temporal, and cell-type-specific expression of NADPH Oxidase isoforms following seizure models in rats.

The NADPH Oxidase (NOX) enzymes are key producers of reactive oxygen species (ROS) and consist of seven different isoforms, distributed across the tissues and cell types. The increasing level of ROS induces oxidative stress playing a crucial role in neuronal death and the development of epilepsy. Recently, NOX2 was reported as a primary source of ROS production, activated by NMDA receptor, a crucial marker of epilepsy development. Here, we demonstrate spatial, temporal, and cellular expression of NOX2 and NOX4 complexes in in-vitro and in-vivo seizure models. We showed that the expression of NOX2 and NOX4 was increased in the initial 24 h following a brief seizure induced by pentylenetetrazol. Interestingly, while this elevated level returns to baseline 48 h following seizure in the cortex, in the hippocampus these levels remain elevated up to one week following the seizure. Moreover, we showed that 1- and 2- weeks following status epilepticus (SE), expression of NOX2 and NOX4 remains significantly elevated both in the cortex and the hippocampus. Furthermore, in in-vitro seizure model, NOX2 and NOX4 isoforms were overexpressed in neurons and astrocytes following seizures. These results suggest that NOX2 and NOX4 in the brain have a transient response to seizures, and these responses temporally vary depending on, seizure duration, brain region (cortex or hippocampus), and cell types.

Japanese encephalitis virus persists in the human reproductive epithelium and porcine reproductive tissues.

Japanese encephalitis virus (JEV) is the emerging and geographically expanding flavivirus and the major causative agent of encephalitis in humans in Asia. There are risks of JEV introduction into the Americas given a large population of amplifying hosts-pigs and wild boars, and insect vectors-Culex mosquitoes. There are emerging concerns about vector-free ways of flavivirus transmission, for example sexual and transplacental Zika virus transmissions, which may change flavivirus epidemiology and expand the geographical range to territories with no insect vectors. It is unknown whether JEV has tropism in the female lower reproductive tract and the potential for sexual transmission in humans. While clinical outcomes of transplacental JEV infection are described in humans and pigs, cellular targets and tissue tropism in the upper reproductive tract are also unknown. Here, we studied JEV infection phenotypes and host transcriptional responses in human reproductive epithelial cells. We found that JEV caused persistent infection and cytopathology in the vaginal epithelium, endometrial epithelium, and trophoblast. Human vaginal epithelial cells infected with JEV had altered transcriptional responses associated with inflammation and disruption of epithelial barrier function. Also, using pigs-the native amplifying host for JEV, we confirmed JEV tropism in the female lower and upper reproductive tracts. We discovered that JEV persists in the vaginal mucosa for at least 28 days and pigs shed the virus in vaginal secretions. We also found JEV persistence in the endometrium and placenta with transplacental and fetal infections. Altogether, we discovered that JEV targets the vaginal epithelium and has the potential for sexual transmission in humans. We also contributed to a better understanding of JEV pathogenesis during transplacental infection. Further studies are needed to better understand the interactions of JEV with reproductive tissues, how persistent infection affects female reproductive functions, and the risks for non-vector transmission.

Estimated GFR Slope Across CKD Stages in Primary Hyperoxaluria Type 1.

RATIONALE & OBJECTIVE: Primary hyperoxaluria type 1 (PH1) is an autosomal recessive disorder of glyoxylate metabolism that results in early-onset kidney stone disease, nephrocalcinosis, and kidney failure. There is an unmet need for reliable markers of disease progression to test effectiveness of new treatments for patients with PH. In this study, we assessed the rate of estimated glomerular filtration rate (eGFR) decline across chronic kidney disease (CKD) glomerular filtration rate (GFR) categories (CKD G2-G5) in a cohort of patients with PH1. STUDY DESIGN: Retrospective observational study. SETTING & PARTICIPANTS: Patients with PH1 enrolled in the Rare Kidney Stone Consortium (RKSC) registry who did not have kidney failure at diagnosis and who had at least 2 eGFR values recorded from within 1 month of diagnosis until their last contact date or incident kidney failure event. PREDICTORS: CKD GFR category, baseline patient and laboratory characteristics. OUTCOME: Annualized rate of eGFR decline. ANALYTICAL APPROACH: Generalized estimating equations and linear regression were used to evaluate the associations between CKD GFR category, baseline patient and laboratory characteristics, and annual change in eGFR during follow-up. RESULTS: Compared with the slope in CKD G2 (-2.3 mL/min/1.73 m2 per year), the mean annual eGFR decline was nominally steeper in CKD G3a (-5.3 mL/min/1.73 m2 per year) and statistically significantly more rapid in CKD G3b and G4 (-14.7 and -16.6 mL/min/1.73 m2 per year, respectively). In CKD G2, older age was associated with a more rapid rate of eGFR decline (P = 0.01). A common PH1-causing variant of alanine glyoxylate aminotransferase, a glycine to arginine substitution at amino acid 170 (G170R), appeared to be associated with less severe annual decline in eGFR. LIMITATIONS: Data at regular time points were not available for all patients due to reliance on voluntary reporting in a retrospective rare disease registry. CONCLUSIONS: The eGFR decline was not uniform across CKD GFR categories in this PH1 population, with a higher rate of eGFR decline in CKD G3b and G4. Thus, CKD GFR category needs to be accounted for when analyzing eGFR change in the setting of PH1.

Clinical characterization of primary hyperoxaluria type 3 in comparison with types 1 and 2.

BACKGROUND: Primary hyperoxaluria (PH) type 3 (PH3) is caused by mutations in the hydroxy-oxo-glutarate aldolase 1 gene. PH3 patients often present with recurrent urinary stone disease in the first decade of life, but prior reports suggested PH3 may have a milder phenotype in adults. This study characterized clinical manifestations of PH3 across the decades of life in comparison with PH1 and PH2. METHODS: Clinical information was obtained from the Rare Kidney Stone Consortium PH Registry (PH1, n = 384; PH2, n = 51; PH3, n = 62). RESULTS: PH3 patients presented with symptoms at a median of 2.7 years old compared with PH1 (4.9 years) and PH2 (5.7 years) (P = 0.14). Nephrocalcinosis was present at diagnosis in 4 (7%) PH3 patients, while 55 (89%) had stones. Median urine oxalate excretion was lowest in PH3 patients compared with PH1 and PH2 (1.1 versus 1.6 and 1.5 mmol/day/1.73 m2, respectively, P < 0.001) while urine calcium was highest in PH3 (112 versus 51 and 98 mg/day/1.73 m2 in PH1 and PH2, respectively, P < 0.001). Stone events per decade of life were similar across the age span and the three PH types. At 40 years of age, 97% of PH3 patients had not progressed to end-stage kidney disease compared with 36% PH1 and 66% PH2 patients. CONCLUSIONS: Patients with all forms of PH experience lifelong stone events, often beginning in childhood. Kidney failure is common in PH1 but rare in PH3. Longer-term follow-up of larger cohorts will be important for a more complete understanding of the PH3 phenotype.