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1.
Kidney Int ; 105(3): 496-507, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38142039

RESUMEN

Primary hyperoxaluria type 1 (PH1) is a childhood-onset autosomal recessive disease, characterized by nephrocalcinosis, multiple recurrent urinary calcium oxalate stones, and a high risk of progressive kidney damage. PH1 is caused by inherent genetic defects of the alanine glyoxylate aminotransferase (AGXT) gene. The in vivo repair of disease-causing genes was exceedingly inefficient before the invention of base editors which can efficiently introduce precisely targeted base alterations without double-strand DNA breaks. Adenine base editor (ABE) can precisely convert A·T to G·C with the assistance of specific guide RNA. Here, we demonstrated that systemic delivery of dual adeno-associated virus encoding a split-ABE8e could artificially repair 13% of the pathogenic allele in AgxtQ84X rats, a model of PH1, alleviating the disease phenotype. Specifically, ABE treatment partially restored the expression of alanine-glyoxylate-aminotransferase (AGT), reduced endogenous oxalate synthesis and alleviated calcium oxalate crystal deposition. Western blot and immunohistochemistry confirmed that ABE8e treatment restored AGT protein expression in hepatocytes. Moreover, the precise editing efficiency in the liver remained stable six months after treatment. Thus, our findings provided a prospect of in vivo base editing as a personalized and precise medicine for PH1 by directly correcting the mutant Agxt gene.


Asunto(s)
Hiperoxaluria Primaria , Hiperoxaluria , Humanos , Ratas , Animales , Niño , Oxalato de Calcio , Edición Génica , ARN Guía de Sistemas CRISPR-Cas , Hiperoxaluria Primaria/genética , Hiperoxaluria Primaria/terapia , Transaminasas/genética , Transaminasas/química , Transaminasas/metabolismo , Alanina , Mutación
2.
Pediatr Surg Int ; 39(1): 200, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37191737

RESUMEN

PURPOSE: Ureterocele has been hypothesized to be the risk factor for febrile urinary tract infections (F-UTIs) in patients with duplex collecting systems, but this has not been proved, and our goal was to assess the relation between ureterocele with duplex collecting systems and F-UTIs. METHODS: We included individual-participant data from patients seen for complicated duplex collecting systems from 2010 to 2020 retrospectively followed. Those with using continuous low-dose antibiotic prophylaxis and incompletely duplicated systems were removed from the study. The participants were divided into two cohorts according to patients with or without ureterocele. The primary endpoint of this study was recurrent F-UTIs. RESULTS: We analyzed medical reports of 300 patients, of which 75% were female. Among the 300 patients, F-UTIs developed in 111/159 (69.8%) patients in the ureterocele group and in 69/141 (48.9%) patients in the no-ureterocele group. Univariate analysis found no discernible difference except in grade of hydronephrosis between ureterocele group and no-ureterocele group. Moreover, Cox proportional regression analysis revealed that patients of duplex system ureterocele might be intrinsically more prone to develop F-UTIs (adjusted hazard ratio 1.894; 95% CI 1.412-2.542; p  <  0.001). CONCLUSION: Among participants with duplex systems, the risk of recurrent F-UTIs in patients with ureterocele was higher than patients without it, and mini-invasive surgical correction should be considered at young age to reduce F-UTIs.


Asunto(s)
Hidronefrosis , Enfermedades Renales , Ureterocele , Infecciones Urinarias , Humanos , Femenino , Lactante , Masculino , Estudios Retrospectivos , Enfermedades Renales/complicaciones , Infecciones Urinarias/epidemiología , Infecciones Urinarias/etiología , Hidronefrosis/complicaciones , Profilaxis Antibiótica , Ureterocele/complicaciones , Ureterocele/diagnóstico por imagen , Ureterocele/cirugía
3.
Small ; 18(43): e2106983, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35187834

RESUMEN

Room-temperature sodium-sulfur (RT-Na-S) batteries are attracting increased attention due to their high theoretical energy density and low-cost. However, the traditional RT-Na-S batteries assembled with glass fiber (GF) separators are still hindered by the polysulfide shuttle effect and sodium dendrite growth, limiting the battery's capacity and cycling stability. Here, a facile and effective method toward commercial polyolefin separators for constructing stable RT-Na-S batteries is presented. By coating commercial polypropylene membrane with core-shell structured MXene@C nanosheets, a powerful dual-functional separator with improved electrolyte wettability that can inhibit polysulfide migration and induce uniform sodium disposition is developed. More importantly, the modified separator can also accelerate the conversion kinetics of sodium polysulfides. Benefiting from these characteristics, the as-prepared RT-Na-S battery exhibits a remarkably enhanced capacity (1159 mAh g-1 at 0.2 C) and excellent cycling performance (95.8% of capacity retention after 650 cycles at 0.5 C). This study opens a promising avenue for the development of high-performance Na-S batteries.

4.
World J Urol ; 40(5): 1211-1216, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35149915

RESUMEN

PURPOSE: To compare the clinical characteristics of pediatric urolithiasis patients with positive and negative molecular diagnoses. METHODS: The clinical characteristics corresponding to pediatric urolithiasis patients that had undergone exome sequencing at our hospital between January 2016 and May 2021 were collected. Genetic analysis results were used to separate patients into positive and negative molecular diagnosis groups. Multivariate logistic regression analyses adjusted for visiting age, sex, ethnicity, province, and body mass index were used to compare differences in medical history, diagnostic imaging findings, and renal function between individuals with and without molecular diagnoses. RESULTS: In total, 194 patients with pediatric urolithiasis of unknown etiology underwent exome sequencing and were included in the present study, of whom 63 obtained urolithiasis-related molecular diagnoses. Relative to cases without a molecular diagnosis, those with a positive molecular diagnosis were more likely to be associated with a positive family history (OR 2.84, 95% CI 1.29-6.29, p = 0.008), consanguineous parents (OR 24.7, 95% CI 1.34-454, p = 0.002), early onset (OR 1.26, 95% CI 1.09-1.45, p < 0.001), nephrocalcinosis (OR 10.6, 95% CI 3.06-36.6, p < 0.001), cast stone (OR 18.9, 95% CI 4.40-81.1, p < 0.001), multiple stones (OR 13.9, 95% CI 6.39-30.2, p < 0.001), bilateral stones (OR 7.04, 95% CI 3.47-14.2, p < 0.001), a lower estimated glomerular filtration rate (OR 1.17, 95% CI 1.07-1.28, p < 0.001), and chronic kidney disease (OR 26.9, 95% CI 1.42-526, p < 0.001). CONCLUSION: A positive family history, consanguineous parents, early onset, nephrocalcinosis, severe stone burden, and impaired renal function are signals of concern that are suggestive of inherited urolithiasis.


Asunto(s)
Nefrocalcinosis , Insuficiencia Renal Crónica , Urolitiasis , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos , Urolitiasis/diagnóstico , Urolitiasis/genética
5.
World J Urol ; 39(7): 2759-2765, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32936332

RESUMEN

PURPOSE: To investigate the prevalence of inherited causes in an early onset urolithiasis cohort and each metabolic subgroup. METHODS: A retrospective analysis of both metabolic and genomic data was performed for the first 105 pediatric urolithiasis patients who underwent exome sequencing at our hospital from February 2016 to October 2018. Measurements included the diagnostic yield of exome sequencing in the entire cohort and each metabolic subgroup (hyperoxaluria, hypocitraturia, hypercalciuria, hyperuricosuria and cystine stone subgroups). The conformity between molecular diagnoses and metabolic evaluation was also evaluated. RESULTS: The present study involved a cohort of 105 pediatric patients with urolithiasis, from which diagnostic variants were identified in 38 patients (36%), including 27 primary hyperoxaluria and 11 cystinuria. In the metabolic subgroup analyses, 41% hyperoxaluria cases were primary hyperoxaluria caused by monogenic defects, and 100% of the causes of cystine stones could be explained by monogenic defects. However, no appropriate inherited causes were identified for hypocitraturia, hypercalciuria, or hyperuricosuria in the cohort. A high conformity (100%) was obtained between the molecular diagnoses and metabolic evaluation. CONCLUSION: Exome sequencing in a cohort of 105 pediatric patients with urolithiasis yielded a genetic diagnosis in 36% of cases and the molecular diagnostic yield varies substantially across different metabolic abnormalities.


Asunto(s)
Urolitiasis/diagnóstico , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Urolitiasis/genética , Urolitiasis/metabolismo , Secuenciación del Exoma
6.
Kidney Int ; 98(4): 947-957, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32464217

RESUMEN

Primary hyperoxaluria type I is caused by mutations in the alanine glyoxylate aminotransferase gene (AGXT), leading to accumulation of glyoxylate and subsequent production of oxalate and urolithiasis. Here, we generated a novel rat model of primary hyperoxaluria type I that carries a D205N mutation in the partially humanized Agxt gene through the CRISPR/Cas9 system. The AgxtD205N mutant rats showed undetectable alanine glyoxylate aminotransferase protein expression, developed hyperoxaluria at 1 month of age and exhibited severe renal calcium oxalate deposition after ethylene glycol challenge. This suggests our novel model is more relevant to the human disease than existing animal models. To test whether this model could be used for the development of innovative therapeutics, SaCas9 targeting hydroxyacid oxidase 1, responsible for metabolizing glycolate into glyoxylate, was delivered via adeno-associated viral vectors into newborn rats with primary hyperoxaluria type 1. This approach generated nearly 30% indels in the Hao1 gene in the liver, leading to 42% lower urine oxalate levels in the treated group than in the control group and preventing the rats with primary hyperoxaluria type 1 from undergoing severe nephrocalcinosis for at least 12 months. Thus, our results demonstrate that this partially humanized AgxtD205N rat strain is a high-performing model of primary hyperoxaluria type 1 for understanding pathology, and the development of novel therapeutics, such as reprogramming of the metabolic pathway through genome editing.


Asunto(s)
Hiperoxaluria Primaria , Hiperoxaluria , Animales , Sistemas CRISPR-Cas , Modelos Animales de Enfermedad , Hiperoxaluria Primaria/genética , Hiperoxaluria Primaria/terapia , Redes y Vías Metabólicas , Ratas , Transaminasas/genética
7.
Small ; 15(10): e1804786, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30721557

RESUMEN

Lithium-sulfur (Li-S) batteries are considered as one of the most potential next-generation rechargeable batteries due to their high theoretical energy density. However, some critical issues, such as low capacity, poor cycling stability, and safety concerns, must be solved before Li-S batteries can be used practically. During the past decade, tremendous efforts have been devoted to the design and synthesis of electrode materials. Benefiting from their tunable structural parameters, hollow porous carbon materials (HPCM) remarkably enhance the performances of both sulfur cathodes and lithium anodes, promoting the development of high-performance Li-S batteries. Here, together with the templated synthesis of HPCM, recent progresses of Li-S batteries based on HPCM are reviewed. Several important issues in Li-S batteries, including sulfur loading, polysulfide entrapping, and Li metal protection, are discussed, followed by a summary on recent research on HPCM-based sulfur cathodes, modified separators, and lithium anodes. After the discussion on emerging technical obstacles toward high-energy Li-S batteries, prospects for the future directions of HPCM research in the field of Li-S batteries are also proposed.

8.
World J Urol ; 37(8): 1713-1721, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30488096

RESUMEN

PURPOSE: We analyzed primary hyperoxaluria (PH) genotype and phenotype in Chinese children. Vitamin B6 response in the patients with genetically confirmed PH1 was also studied. METHODS: We, respectively, analyzed 80 children with urinary stones. Sixty-four children were diagnosed with hyperoxaluria. Twenty-one children consented to genetic evaluation (targeted gene panel-based and whole-exome sequencing), and DNA was obtained from the children and both the parents. RESULTS: PH accounted for 57.1% (12/21) of hyperoxaluria cases. We reported 12 PH cases, including 5 PH1, 1 PH2, and 6 PH3 cases; 2 novel mutations in AGXT and GRHPR each and 4 HOGA1 mutations were identified. The mutations in AGXT and GRHPR were c0.1161C>A and c0.551C>A, and c0.370C>T and c0.864_865delTG, respectively. Four HOGA1 mutations, c0.290G>A, c0.110G>A, c0.554C>T and c0.834_834 + 1delinsTT, were not reported previously. The average urine Ox 24 level in the PH patients was 0.91 mmol/1.73 m2. Moreover, the average urine Ox 24 level in the PH1 patients (1.07 mmol/1.73 m2) was higher than that in the PH2 and PH3 patients (0.73 mmol/1.73 m2 and 0.71 mmol/1.73 m2, respectively). The eGFR of the PH1 patients (76.86 mL/min) was lower than that of the PH2 and PH3 patients (132 mL/min and 136 mL/min, respectively). CONCLUSIONS: PH incidence was higher than the reported PH incidence in children with urinary stones. Hence, we suggested that genetic examination was necessary for all the children with hyperoxaluria. These novel mutations broaden the range of known gene mutations in PH.


Asunto(s)
Hiperoxaluria Primaria/genética , Cálculos Urinarios/genética , Pueblo Asiatico , Niño , Preescolar , Femenino , Variación Genética , Genotipo , Humanos , Hiperoxaluria Primaria/complicaciones , Lactante , Masculino , Mutación , Fenotipo , Cálculos Urinarios/complicaciones
9.
Pediatr Nephrol ; 34(10): 1785-1790, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31123811

RESUMEN

BACKGROUND: Primary hyperoxaluria type 3 (PH3) is characterized by mutations in the 4-hydroxy-2-oxoglutarate aldolase (HOGA1) gene. PH3 patients are thought to present with a less severe phenotype than PH1 and PH2 patients. However, the clinical characteristics of PH3 patients have yet to be defined in sufficient detail. The aims of this study were to report HOGA1 mutations of PH3 in Chinese children, and to analyze the genotype and clinical characteristics of these PH3 patients. METHODS: Genetic analysis (targeted gene panel-based and/or whole-exome sequencing) of HOGA1 was performed in 52 patients with a high suspicion of PH3, and DNA was obtained from the patient and both the parents. The clinical, biochemical, and genetic data of these 12 patients identified with HOGA1 mutations were subsequently retrospectively reviewed. RESULTS: These 12 patients were identified with HOGA1 mutation. The median onset of clinical symptoms was 18.25 (range 5-38) months. In total, 14 different mutations were identified including 9 novel mutations in these 12 patients with PH3. All of these 12 patients initially presented with urolithiasis, and 3 patients among them comorbid urinary tract infection (UTI) as another initial symptom. Ten patients experienced hyperoxaluria (average oxalate 0.77 mmol/1.73 m2/24h). In contrast, urine calcium excretion was normal in 8 patients and 2 patients with hypercalciuria (urine calcium > 4 mg/kg/24 h). At the time of diagnosis, estimated GFR was 155.6 ml/min per 1.73 m2, and at last follow-up time (17.3 months later from diagnosis on average), estimated GFR was 157.5 ml/min per 1.73 m2. To date, none of the patients has impaired renal function based on and progressed to ESRD. CONCLUSIONS: We found that PH3 was significantly diagnosed in our urolithiasis patients during childhood. Nine novel HOGA1 mutations were identified in association with PH3, which provide a first-line investigation in Chinese PH3 patients. The eGFR was normal in all children with PH3. This finding is in contrast to the early impairment of renal function in PH1 and PH2.


Asunto(s)
Hiperoxaluria Primaria/genética , Oxo-Ácido-Liasas/genética , Urolitiasis/genética , Edad de Inicio , Preescolar , China , Análisis Mutacional de ADN , Femenino , Pruebas Genéticas , Tasa de Filtración Glomerular , Humanos , Hiperoxaluria Primaria/complicaciones , Hiperoxaluria Primaria/diagnóstico , Hiperoxaluria Primaria/orina , Lactante , Masculino , Mutación , Oxalatos/orina , Estudios Retrospectivos , Urolitiasis/orina , Secuenciación del Exoma
10.
J Environ Manage ; 232: 254-263, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30476687

RESUMEN

In order to reduce landfill disposal of waterworks sludge (alum sludge) and incinerated sewage sludge ash (ISSA), this study proposed an innovative approach for upcycling them into value-added controlled low-strength materials (CLSM). Waterworks sludge interfered with cement hydration reaction and delayed the stiffening time of CLSM (>10 h) due to its high organics content (5%). The addition of triethanolamine (TEA) with a dosage of 0.1 wt% of binder effectively shortened the stiffening time to 4.5 h. The lab-scale results suggested that the optimal CLSM design (6% cement, 14% ISSA, 8% sludge, and 72% recycled fine aggregate at a water/binder ratio of 1.2) complied with the standard requirement of flowability (>200 mm), stiffening time (<5 h), and compressive strength (0.3-2.1 MPa). The pilot-scale field tests further confirmed that the sludge-incorporated CLSM achieved a high flowability (220 mm), short stiffening time (4 h), low compressive strength (1.38 MPa), and easy re-excavatability after 3 months. This study demonstrated that waterworks sludge can be potentially transformed into sustainable construction materials for urban development.


Asunto(s)
Materiales de Construcción , Aguas del Alcantarillado , Fuerza Compresiva , Reciclaje , Agua
11.
Small ; 14(24): e1800759, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29774641

RESUMEN

2D layered metal hydroxides (LMH) are promising materials for electrochemical energy conversion and storage. Compared with exfoliation of bulk layered materials, wet chemistry synthesis of 2D LMH materials under mild conditions still remains a big challenge. Here, an "MgO-mediated strategy" for mass production of various 2D LMH nanosheets is presented by hydrolyzing MgO in metal salt aqueous solutions at room temperature. Benefiting from this economical and scalable strategy, ultrathin LMH nanosheets (M = Ni, Fe, Co, NiFe, and NiCo) and their derivatives (e.g., metal oxides and sulfides) can be synthesized in high yields. More importantly, this strategy opens up opportunities to fabricate hierarchically structured LMH nanosheets, resulting in high-performance electrocatalysts for the oxygen- and hydrogen-evolution reactions to realize stable overall water splitting with a low cell voltage of 1.55 V at 10 mA cm-2 . This work provides a powerful platform for the synthesis and applications of 2D materials.

12.
Nanotechnology ; 29(23): 235501, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29561737

RESUMEN

Wearable strain sensors based on nanomaterial/elastomer composites have potential applications in flexible electronic skin, human motion detection, human-machine interfaces, etc. In this research, a type of high performance strain sensors has been developed using fragmentized carbon nanotube/polydimethylsiloxane (CNT/PDMS) composites. The CNT/PDMS composites were ground into fragments, and a liquid-induced densification method was used to fabricate the strain sensors. The strain sensors showed high sensitivity with gauge factors (GFs) larger than 200 and a broad strain detection range up to 80%, much higher than those strain sensors based on unfragmentized CNT/PDMS composites (GF < 1). The enhanced sensitivity of the strain sensors is ascribed to the sliding of individual fragmentized-CNT/PDMS-composite particles during mechanical deformation, which causes significant resistance change in the strain sensors. The strain sensors can differentiate mechanical stimuli and monitor various human body motions, such as bending of the fingers, human breathing, and blood pulsing.

13.
BJU Int ; 116(4): 634-40, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25327554

RESUMEN

OBJECTIVE: To investigate whether diacylglycerol kinase κ (DGKK) is a susceptibility gene for hypospadias in the Han Chinese population as has been suggested by previous publications. PATIENTS SUBJECTS AND METHODS: A case-control study involving 466 patients with hypospadias and 402 healthy subjects was conducted to assess the relationship between DGKK single nucleotide polymorphisms (SNPs) and hypospadias risk in the Han Chinese population. The 466 hypospadias patients were further divided into mild, moderate and severe subgroups for analysis. RESULTS: Six SNPs (rs1934179, rs4143304, rs9969978, rs1934188, rs4826632 and rs4599945) were marginally associated with mild and moderate hypospadias [odds ratios (ORs) > 1, P = 0.05 to P < 0.1), whereas no significant relationship was seen with the severe cases (ORs >1, P > 0.1). After correcting for multiple testing, it was determined that neither individual SNPs nor individual haplotypes were associated with hypospadias. To evaluate this relationship in multiple populations, we performed a meta-analysis on six SNPs, using combined data from our present results and those of previous studies of different races (including 1966 patients and 2492 controls). Six SNPs (rs1934179, rs4143304, rs9969978, rs1934188, rs7063116 and rs1934190) were significantly associated with mild/moderate hypospadias (ORs >1, P < 0.05), and rs1934179 was significantly associated with severe hypospadias (OR > 1, P < 0.05). CONCLUSIONS: DGKK gene variants do not appear to play a major role in hypospadias susceptibility in the Chinese Han population. Our meta-analysis supports the hypothesis that DGKK is a common risk gene for hypospadias, particularly in cases of mild or moderate hypospadias in Caucasian populations.


Asunto(s)
Pueblo Asiatico/genética , Diacilglicerol Quinasa/genética , Hipospadias/epidemiología , Hipospadias/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Estudios de Casos y Controles , China , Estudios de Asociación Genética , Humanos , Desequilibrio de Ligamiento , Masculino
14.
ACS Cent Sci ; 10(4): 852-859, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38680562

RESUMEN

Proton exchange membrane water electrolysis (PEMWE) is a promising solution for the conversion and storage of fluctuating renewable energy sources. Although tremendously efficient materials have been developed, commercial PEMWE products still cannot fulfill industrial demands regarding efficiency and stability. In this work, we demonstrate that the stress distribution, a purely mechanical parameter in electrolyzer assembly, plays a critical role in overall efficiency and stability. The conventional cell structure, which usually adopts a serpentine flow channel (S-FC) to deliver and distribute reactants and products, resulted in highly uneven stress distribution. Consequently, the anode catalyst layer (ACL) under the high stress region was severely deformed, whereas the low stress region was not as active due to poor electrical contact. To address these issues, we proposed a Ti mesh flow channel (TM-FC) with gradient pores to reduce the stress inhomogeneity. Consequently, the ACL with TM-FC exhibited 27 mV lower voltage initially and an 8-fold reduction in voltage degradation rate compared to that with S-FC at 2.0 A/cm2. Additionally, the applicability of the TM-FC was demonstrated in cross-scale electrolyzers up to 100 kW, showing a voltage increase of only 20 mV (accounting for less than 2% of overall voltage) after three orders of magnitude scaleup.

15.
Adv Mater ; 36(28): e2402780, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38661112

RESUMEN

The high cost of proton exchange membrane water electrolysis (PEMWE) originates from the usage of precious materials, insufficient efficiency, and lifetime. In this work, an important degradation mechanism of PEMWE caused by dynamics of ionomers over time in anode catalyst layer (ACL), which is a purely mechanical degradation of microstructure, is identified. Contrary to conventional understanding that the microstructure of ACL is static, the micropores are inclined to be occupied by ionomers due to the localized swelling/creep/migration, especially near the ACL/PTL (porous transport layer) interface, where they form transport channels of reactant/product couples. Consequently, the ACL with increased ionomers at PTL/ACL interface exhibit rapid and continuous degradation. In addition, a close correlation between the microstructure of ACL and the catalyst ink is discovered. Specifically, if more ionomers migrate to the top layer of the ink, more ionomers accumulate at the ACL/PEM interface, leaving fewer ionomers at the ACL/PTL interface. Therefore, the ionomer distribution in ACL is successfully optimized, which exhibits reduced ionomers at the ACL/PTL interface and enriches ionomers at the ACL/PEM interface, reducing the decay rate by a factor of three when operated at 2.0 A cm-2 and 80 °C. The findings provide a general way to achieve low-cost hydrogen production.

16.
ACS Appl Mater Interfaces ; 16(13): 16408-16417, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38502312

RESUMEN

The widespread application of proton exchange membrane water electrolyzers (PEMWEs) is hampered by insufficient lifetime caused by degradation of the anode catalyst layer (ACL). Here, an important degradation mechanism has been identified, attributed to poor mechanical stability causing the mass transfer channels to be blocked by ionomers under operating conditions. By using liquid-phase atomic force microscopy, we directly observed that the ionomers were randomly distributed (RD) in the ACL, which occupied the mass transfer channels due to swelling, creeping, and migration properties. Interestingly, we found that alternating treatments of the ACL in different water/temperature environments resulted in forming three-dimensional ionomer networks (3D INs) in the ACL, which increased the mechanical strength of microstructures by 3 times. Benefitting from the efficient and stable mass transfer channels, the lifetime was improved by 19 times. A low degradation rate of approximately 3.0 µV/h at 80 °C and a high current density of 2.0 A/cm2 was achieved on a 50 cm2 electrolyzer. These data demonstrated a forecasted lifetime of 80 000 h, approaching the 2026 DOE lifetime target. This work emphasizes the importance of the mechanical stability of the ACL and offers a general strategy for designing and developing a durable PEMWE.

17.
J Urol ; 189(4): 1498-502, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23201375

RESUMEN

PURPOSE: We evaluated the safety and efficacy of extracorporeal shock wave lithotripsy in the treatment of single melamine induced urolithiasis in infants and young children. MATERIALS AND METHODS: A total of 189 infants and young children with single melamine induced urolithiasis were referred to our center for treatment with extracorporeal shock wave lithotripsy between March 2009 and July 2010. Location of the calculus was proximal ureteral in 17 patients, mid ureteral in 5, distal ureteral in 26 and kidney in 141. Stone size ranged from 3.8 to 25 mm (mean ± SD 9.79 ± 3.83). RESULTS: All patients underwent extracorporeal shock wave lithotripsy using the same device with an energy ranging from 8 to 12 kV. Stone-free rate was 97.88%, clinically insignificant residual fragment rate was 1.59% and repeat treatment rate was 2.65%. A total of 180 patients (95.24%) required only 1 lithotripsy session and 5 (2.65%) required 2 sessions. Mean ± SD number of shock waves delivered per session was 580.36 ± 190.69 (range 65 to 950). Extracorporeal shock wave lithotripsy failed to fragment stones in only 1 infant, who had a proximal ureteral stone. A total of 181 specimens were collected and analyzed by infrared spectrum, with results demonstrating that the main composition was uric acid and melamine. All patients were followed for a mean of 28 months (range 20 to 36). No severe complication, such as renal subcapsular hemorrhage, hypertension, kidney rupture or lung injury, was observed. CONCLUSIONS: Extracorporeal shock wave lithotripsy with low energy can effectively disintegrate melamine induced calculi. This approach has become our preferred method for treating single melamine induced urolithiasis in infants and young children.


Asunto(s)
Litotricia/métodos , Resinas Sintéticas/efectos adversos , Triazinas/efectos adversos , Urolitiasis/terapia , Preescolar , China , Femenino , Contaminación de Alimentos , Humanos , Lactante , Fórmulas Infantiles/química , Litotricia/efectos adversos , Litotricia/instrumentación , Masculino , Triazinas/análisis , Ácido Úrico/análisis , Urolitiasis/inducido químicamente , Urolitiasis/complicaciones
18.
Eur J Pediatr ; 172(12): 1693-5, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23559328

RESUMEN

A 1-year-old boy was referred to our department with a pseudoduplication of the external genitalia present since birth. At surgery, we performed a complete excision of the mass through a "Y-type" perineal incision. The boy was taken to our department for a regular physical examination 2 years after the surgery. The appearance of the perineal region was satisfactory.


Asunto(s)
Genitales Masculinos/anomalías , Genitales Masculinos/cirugía , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Perineo/anatomía & histología , Perineo/cirugía
19.
Zool Res ; 44(6): 993-1002, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37759334

RESUMEN

Targeting key enzymes that generate oxalate precursors or substrates is an alternative strategy to eliminate primary hyperoxaluria type I (PH1), the most common and life-threatening type of primary hyperoxaluria. The compact Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) from the Prevotella and Francisella 1 (Cpf1) protein simplifies multiplex gene editing and allows for all-in-one adeno-associated virus (AAV) delivery. We hypothesized that the multiplex capabilities of the Cpf1 system could help minimize oxalate formation in PH1 by simultaneously targeting the hepatic hydroxyacid oxidase 1 ( Hao1) and lactate dehydrogenase A ( Ldha) genes. Study cohorts included treated PH1 rats ( Agxt Q84X rats injected with AAV-AsCpf1 at 7 days of age), phosphate-buffered saline (PBS)-injected PH1 rats, untreated PH1 rats, and age-matched wild-type (WT) rats. The most efficient and specific CRISPR RNA (crRNA) pairs targeting the rat Hao1 and Ldha genes were initially screened ex vivo. In vivo experiments demonstrated efficient genome editing of the Hao1 and Ldha genes, primarily resulting in small deletions. This resulted in decreased transcription and translational expression of Hao1 and Ldha. Treatment significantly reduced urine oxalate levels, reduced kidney damage, and alleviated nephrocalcinosis in rats with PH1. No liver toxicity, ex-liver genome editing, or obvious off-target effects were detected. We demonstrated the AAV-AsCpf1 system can target multiple genes and rescue the pathogenic phenotype in PH1, serving as a proof-of-concept for the development of multiplex genome editing-based gene therapy.


Asunto(s)
Hiperoxaluria Primaria , Animales , Ratas , Edición Génica/métodos , Edición Génica/veterinaria , Hiperoxaluria Primaria/genética , Hiperoxaluria Primaria/terapia , Hiperoxaluria Primaria/veterinaria , Hígado , Oxalatos
20.
Small ; 8(24): 3816-22, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-22903778

RESUMEN

A versatile system combining chemotherapy with photothermal therapy for cancer cells using Pd nanosheet-covered hollow mesoporous silica nanoparticles is reported. While the hollow mesoporous silica core can be used to load anticancer drugs (i.e., doxorubicin) for chemotherapy, the Pd nanosheets on the surface of particles can convert NIR light into heat for photothermal therapy. More importantly, the loading of Pd nanosheets on hollow mesoporous silica nanospheres can dramatically increase the amount of cellular internalization of the Pd nanosheets: almost 11 times higher than the unloaded Pd nanosheets. The as-prepared nanocomposites efficiently deliver both drugs and heat to cancer cells to improve the therapeutic efficiency with minimal side effects. Compared with chemotherapy or photothermal therapy alone, the combination of chemotherapy and phototherapy can significantly improve the therapeutic efficacy, exhibiting a synergistic effect.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanocáscaras , Neoplasias/terapia , Paladio , Dióxido de Silicio , Antineoplásicos/administración & dosificación , Terapia Combinada , Doxorrubicina/administración & dosificación , Células Hep G2 , Calor/uso terapéutico , Humanos , Nanocompuestos/administración & dosificación , Nanocompuestos/química , Nanocompuestos/ultraestructura , Nanocáscaras/administración & dosificación , Nanocáscaras/química , Nanocáscaras/ultraestructura , Nanotecnología , Fototerapia
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