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1.
J Cell Biochem ; 123(11): 1817-1826, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35959632

RESUMEN

Understanding the mechanisms responsible for the kidney's defense against ascending uropathogen is critical to devise novel treatment strategies against increasingly antibiotic resistant uropathogen. Growing body of evidence indicate Intercalated cells of the kidney as the key innate immune epithelial cells against uropathogen. The aim of this study was to find orthologous and differentially expressed bacterial defense genes in human versus murine intercalated cells. We simultaneously analyzed 84 antibacterial genes in intercalated cells enriched from mouse and human kidney samples. Intercalated cell "reporter mice" were exposed to saline versus uropathogenic Escherichia coli (UPEC) transurethrally for 1 h in vivo, and intercalated cells were flow sorted. Human kidney intercalated cells were enriched from kidney biopsy using magnetic-activated cell sorting and exposed to UPEC in vitro for 1 h. RT2 antibacterial PCR array was performed. Mitogen-activated protein kinase kinase kinase 7 (MAP3K7) messenger RNA (mRNA) expression increased in intercalated cells of both humans and mice following UPEC exposure. Intercalated cell MAP3K7 protein expression was defined by immunofluorescence and confocal imaging analysis, was consistent with the increased MAP3K7 mRNA expression profiles defined by PCR. The presence of the orthologous innate immune gene MAP3K7/TAK1 suggests that it may be a key regulator of the intercalated cell antibacterial response and demands further investigation of its role in urinary tract infection pathogenesis.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli Uropatógena , Humanos , Ratones , Animales , Escherichia coli Uropatógena/genética , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Riñón , Células Epiteliales/microbiología , Genes Reguladores , Inmunidad Innata/genética , Antibacterianos , ARN Mensajero
3.
Nat Commun ; 12(1): 2405, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33893305

RESUMEN

Kidney intercalated cells are involved in acid-base homeostasis via vacuolar ATPase expression. Here we report six human intercalated cell subtypes, including hybrid principal-intercalated cells identified from single cell transcriptomics. Phagosome maturation is a biological process that increases in biological pathway analysis rank following exposure to uropathogenic Escherichia coli in two of the intercalated cell subtypes. Real time confocal microscopy visualization of murine renal tubules perfused with green fluorescent protein expressing Escherichia coli or pHrodo Green E. coli BioParticles demonstrates that intercalated cells actively phagocytose bacteria then acidify phagolysosomes. Additionally, intercalated cells have increased vacuolar ATPase expression following in vivo experimental UTI. Taken together, intercalated cells exhibit a transcriptional response conducive to the kidney's defense, engulf bacteria and acidify the internalized bacteria. Intercalated cells represent an epithelial cell with characteristics of professional phagocytes like macrophages.


Asunto(s)
Células Epiteliales/inmunología , Riñón/inmunología , Fagocitos/inmunología , Escherichia coli Uropatógena/inmunología , Ácidos/química , Animales , Células Cultivadas , Células Epiteliales/citología , Células Epiteliales/metabolismo , Perfilación de la Expresión Génica/métodos , Humanos , Riñón/citología , Riñón/metabolismo , Túbulos Renales Colectores/citología , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Confocal , Fagocitos/citología , Análisis de la Célula Individual/métodos , ATPasas de Translocación de Protón Vacuolares/metabolismo
4.
PLoS One ; 15(7): e0235328, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32628701

RESUMEN

OBJECTIVE: Current urinary tract infection (UTI) diagnostic strategies that rely on leukocyte esterase have limited accuracy. We performed an aptamer-based proteomics pilot study to identify urine protein levels that could differentiate a culture proven UTI from culture negative samples, regardless of pyuria status. METHODS: We analyzed urine from 16 children with UTIs, 8 children with culture negative pyuria and 8 children with negative urine culture and no pyuria. The urine levels of 1,310 proteins were quantified using the Somascan™ platform and normalized to urine creatinine. Machine learning with support vector machine (SVM)-based feature selection was performed to determine the combination of urine biomarkers that optimized diagnostic accuracy. RESULTS: Eight candidate urine protein biomarkers met filtering criteria. B-cell lymphoma protein, C-X-C motif chemokine 6, C-X-C motif chemokine 13, cathepsin S, heat shock 70kDA protein 1A, mitogen activated protein kinase, protein E7 HPV18 and transgelin. AUCs ranged from 0.91 to 0.95. The best prediction was achieved by the SVMs with radial basis function kernel. CONCLUSIONS: Biomarkers panel can be identified by the emerging technologies of aptamer-based proteomics and machine learning that offer the potential to increase UTI diagnostic accuracy, thereby limiting unneeded antibiotics.


Asunto(s)
Aptámeros de Nucleótidos/química , Proteómica/métodos , Máquina de Vectores de Soporte , Urinálisis/métodos , Infecciones Urinarias/diagnóstico , Adolescente , Biomarcadores/orina , Niño , Preescolar , Femenino , Humanos , Masculino , Proyectos Piloto , Estudios Prospectivos , Infecciones Urinarias/orina
5.
J Pediatr Urol ; 16(2): 169-177, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31956092

RESUMEN

PURPOSE: Estimated glomerular filtration rate (eGFR) in the general population is stable in children after 2 years of age until adulthood. In the first three decades after age 18, eGFR decreases by 0.3-0.8 ml/min/1.73 m2/year. Little data exists regarding eGFR changes in the spina bifida (SB) population given variability in muscle mass. In the absence of a validated SB-specific eGFR formula, the performance of different eGFR formulas may vary. We performed a cross-sectional study (1) to determine trends in eGFR with increasing age in children and adults with SB and (2) to compare eGFRs calculated using different formulas. METHODS: We retrospectively reviewed records of patients 2-50 years old with SB followed at our institution (2014-2019). We determined eGFR using four pediatric formulas (2-17 years: CKiDSCr, CKiDCys, CKiDSCr-Cys, ZappitelliSCr-Cys) and four adult formulas (18 + years: MDRDSCr, CKD-EPISCr, CKD-EPICys, CKD-EPISCr-Cys). One eGFR per patient was included (most recent eGFR for those with serial measurements). Patients were categorized as chronic kidney disease (CKD) stage 2 (eGFR 60-89) and Stage 3+ (<60). Non-parametric tests, linear regression, and Spearman's correlation were used for analysis. RESULTS: Among 209 children with SB (median age 10.3 years), depending on the formula used, eGFR decreased by -0.7 to -1.8 ml/min/1.73 m2/year (CKiDCys, CKiDScr, p ≤ 0.001), remained stable (CKiDSCr-Cys, p = 0.41), or increased by +2.7/year (ZappitelliSCr-Cys, p < 0.001) (Figure). The proportion of children with CKD 2 or higher varied between formulas (11.5-58.9%, p < 0.001). Correlations between pediatric formulas were negligible to moderate. Comparing any two formulas, 12.0-65.6% of children were assigned a different CKD stage. Among 164 adults (median age 26.3), eGFR decreased for each formula (range: -1.3 to -2.2/year, p ≤ 0.01) (Figure). The proportion of adults with CKD 2 or higher varied between formulas (9.2-30.5%, p < 0.001). Correlations between adult formulas were moderate to very high. Comparing any two formulas, 8.5-26.8% of adults were assigned a different CKD stage. COMMENT: We cannot reliably determine whether eGFR changed during childhood. Among adults, eGFR decreased with age for every formula evaluated at greater than twice the general population rate. Without a validated SB-specific eGFR formula, we are left with formulas providing different results. CONCLUSIONS: Estimated GFR among adults with SB appears to deteriorate at a higher rate than in the general population. Due to lack of precision of accepted eGFR formulas in the SB population, this may be a real phenomenon, an artifact of inaccurate eGFR formulas, or both. A validated SB-specific eGFR formula is needed.


Asunto(s)
Insuficiencia Renal Crónica , Disrafia Espinal , Adolescente , Adulto , Niño , Preescolar , Creatinina , Estudios Transversales , Tasa de Filtración Glomerular , Humanos , Persona de Mediana Edad , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Estudios Retrospectivos , Disrafia Espinal/complicaciones , Adulto Joven
6.
Pediatr Neonatol ; 61(2): 195-200, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31761714

RESUMEN

BACKGROUND: The 2011 American Academy of Pediatrics clinical practice guideline recommends when to obtain renal and bladder ultrasound (RBUS) and voiding cystourethrography (VCUG) following febrile urinary tract infection (UTI) for children age 2-24 months. However, there is not consensus about when to obtain imaging in neonates. The objective of this study is to evaluate UTI diagnostic criteria along with RBUS and VCUG in neonates admitted to the NICU in the first 3 months of life. METHODS: A retrospective electronic medical record review was performed of neonates admitted to Nationwide Children's Hospital system NICUs between January 2010 and December 2014 with UTI as a primary or secondary diagnosis. Urine culture results were evaluated versus established UTI criteria and renal US and VCUG results were compared. RESULTS: Of 81 patients with a straight catheterized urine culture obtained, 28 patients met laboratory criteria for diagnosis of UTI and all but 4 had a RBUS. Urine cultures had an equal distribution of Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, and Coagulase negative staphylococcus. RBUS showed dilation of the collecting system in 37.5% of patients with UTI compared to 41.3% without UTI. VCUG showed vesicourteral reflux (VUR) on 41.7% of those with UTI compared to 34.8% without UTI. For patients with UTI, the sensitivity of RBUS for VUR on VCUG was 60% with CI [0.17, 0.93] and specificity was 43% with CI [0.12, 0.80]. In patients without UTI, sensitivity of RBUS for VUR on VCUG was 63% with CI [0.26, 0.90] and specificity was 71% with CI [0.42, 0.90]. CONCLUSIONS: Fewer than half of neonates that were diagnosed clinically with UTI met laboratory criteria for a UTI. Positive urine cultures grew a wide variety of organisms. The sensitivity of renal ultrasound for VUR is only about 60%.


Asunto(s)
Riñón/diagnóstico por imagen , Vejiga Urinaria/diagnóstico por imagen , Infecciones Urinarias/diagnóstico , Femenino , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Estudios Retrospectivos , Ultrasonografía , Infecciones Urinarias/diagnóstico por imagen , Reflujo Vesicoureteral/diagnóstico por imagen
7.
Sci Rep ; 9(1): 545, 2019 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-30679625

RESUMEN

The renal collecting duct consists of intercalated cells (ICs) and principal cells (PCs). We have previously demonstrated that collecting ducts have a role in the innate immune defense of the kidney. Transcriptomics is an important tool used to enhance systems-level understanding of cell biology. However, transcriptomics performed on whole kidneys provides limited insight of collecting duct cell gene expression, because these cells comprise a small fraction of total kidney cells. Recently we generated reporter mouse models to enrich collecting duct specific PC and ICs and reported targeted gene expression of anti-microbial peptide genes. Here we report transcriptomics on enriched ICs and PCs and performed a pilot study sequencing four single ICs. We identified 3,645 genes with increased relative expression in ICs compared to non-ICs. In comparison to non-PCs, 2,088 genes had higher relative expression in PCs. IC associated genes included the innate interleukin 1 receptor, type 1 and the antimicrobial peptide(AMP) adrenomedullin. The top predicted canonical pathway for enriched ICs was lipopolysaccharide/Interleukin 1 mediated inhibition of Retinoid X Receptor alpha function and decreased Retinoid X Receptor expression was confirmed to occur 1-hour post experimental murine UTI in ICs but not in non-ICs.


Asunto(s)
Células Epiteliales/metabolismo , Perfilación de la Expresión Génica/métodos , Túbulos Renales Colectores/citología , Túbulos Renales Colectores/inmunología , Lipopolisacáridos/metabolismo , Receptor alfa X Retinoide/antagonistas & inhibidores , Receptor alfa X Retinoide/metabolismo , Animales , Acuaporina 2/genética , Acuaporina 2/metabolismo , Femenino , Inmunidad Innata/genética , Interleucina-1/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proyectos Piloto , Transducción de Señal/genética , Transcriptoma/inmunología , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo
8.
Urology ; 115: 168-170, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29499256

RESUMEN

Nephrogenic diabetes insipidus (NDI), a rare cause of polyuria and polydipsia in children, is usually managed with medications and careful monitoring of water intake. We present a child who was incidentally found to have right hydronephrosis secondary to ureteropelvic junction obstruction, and was subsequently also diagnosed with NDI. After being medically managed, he underwent open right pyeloplasty. His polydipsia abated within 1 month of surgery, and he has done well off of medications since that time. NDI resolution after correction of obstructive uropathy in adults has been reported, but this represents a novel case in pediatrics.


Asunto(s)
Diabetes Insípida Nefrogénica/complicaciones , Obstrucción Ureteral/complicaciones , Obstrucción Ureteral/cirugía , Humanos , Hidronefrosis/etiología , Lactante , Pelvis Renal/cirugía , Masculino , Polidipsia/etiología , Poliuria/etiología
9.
Am J Physiol Renal Physiol ; 315(4): F812-F823, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28468965

RESUMEN

The urinary tract is usually culture negative despite its close proximity to microbial flora. The precise mechanism by which the kidneys and urinary tract defends against infection is not well understood. The initial kidney cells to encounter ascending pathogens are the collecting tubule cells that consist of principal cells (PCs) that express aquaporin 2 (AQP2) and intercalated cells (ICs) that express vacuolar H+-ATPase (V-ATPase, B1 subunit). We have previously shown that ICs are involved with the human renal innate immune defense. Here we generated two reporter mice, VATPase B1-cre+tdT+ mice to fluorescently label ICs and AQP2-cre+tdT+ mice to fluorescently label PCs, and then performed flow sorting to enrich PCs and ICs for analysis. Isolated ICs and PCs along with proximal tubular cells were used to measure antimicrobial peptide (AMP) mRNA expression. ICs and PCs were significantly enriched for AMPs. Isolated ICs responded to uropathogenic Escherichia coli (UPEC) challenge in vitro and had higher RNase4 gene expression than control while both ICs and PCs responded to UPEC challenge in vivo by upregulating Defb1 mRNA expression. To our knowledge, this is the first report of isolating murine collecting tubule cells and performing targeted analysis for multiple classes of AMPs.


Asunto(s)
Acuaporina 2/inmunología , Células Epiteliales/metabolismo , Túbulos Renales Colectores/inmunología , Reacción en Cadena de la Polimerasa , Animales , Acuaporina 2/genética , Inmunidad Innata/inmunología , Riñón/inmunología , Riñón/metabolismo , Ratones Transgénicos , Reacción en Cadena de la Polimerasa/métodos , Regulación hacia Arriba/inmunología , ATPasas de Translocación de Protón Vacuolares/inmunología , ATPasas de Translocación de Protón Vacuolares/metabolismo
10.
Front Pediatr ; 5: 175, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28848728

RESUMEN

AIM: To find the trend in patient's visits to our centers for vesicoureteral reflux (VUR). We hypothesize that VUR diagnosis and hence possible nephropathy recognition may be diminishing because of changing practice patterns. METHODS: Data were extracted from electronic medical records for new and follow-up patients aged 0-18 years with ICD-9/10 codes to correspond with VUR, VUR unilateral, VUR bilateral, and VUR with reflux nephropathy, as well as new patients with diagnoses of urinary tract infections (UTI) and pyelonephritis at two major pediatric centers from 2012 to 2015. Figures and statistics to reflect absolute clinic visits and annual trends were created with SPSS 2010. Linear regression was applied. RESULTS: Annually, Le Bonheur Children's Hospital and Nationwide Children's Hospital experienced an average decrease of 13 and 17% in total VUR visits, and an average decrease of 22 and 27% in VUR nephropathy visits, respectively, for each institution. Patient visits for UTIs were reduced an average of 16% annually in both centers. Linear regression demonstrated that number of patients (patients/year ± SE) decreased annually 69 ± 19 (P = 0.02), 7 ± 2 (P = 0.02), and 67 ± 25 (P = 0.04) for VUR, VUR nephropathy, and UTI, respectively. CONCLUSION: We conclude that the decreased number of VUR and VUR nephropathy cases identified in subspecialty clinics (Nephrology/Urology) at two major children's hospitals reflect a possible decreased identification of VUR. This trend may also be due to decreased referral of low grade cases of VUR. We cannot conclude that "undifferentiated UTI" referrals increased concomitantly to account for the decreased VUR as our data reflects a decreased trend in those visits as well. We suggest that clinicians following the American Academy of Pediatrics guidelines ensure that all UTI are accounted for and surveillance is appropriately escalated for recurrent UTI or abnormal imaging results.

11.
Curr Treat Options Pediatr ; 2(2): 82-93, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27570729

RESUMEN

The past 30 years have seen broad changes in the diagnosis and management of vesicoureteral reflux (VUR). Recently, a clinical debate has generated an open discussion in academic circles. New evidence has shifted treatment patterns away from widespread surgical management and recently brought into question some pharmacologic treatments. VUR is usually not hazardous by itself but is a significant risk factor for urinary tract infection (UTI) and less commonly, renal scarring and insufficiency. Given the costs and morbidity of UTI as well as the potential for significant renal injury, our approach remains conservative. Careful follow-up, parental education about pathophysiology and management of VUR and UTI, and management of bowel and bladder dysfunction (BBD) when present, are the foundation of treatment. Additionally, though we recognize the limitation of continuous antibiotic prophylaxis (CAP), we believe the benefits outweigh the risks and costs for many patients. Careful observation can be considered in patients with a single medical home, parental understanding of what UTI signs and symptoms are, low grade VUR, no history of complicated UTIs and close follow-up. Surgical management remains a relevant option for select patients who fail conservative measures with breakthrough UTIs or failure to resolve. Minimally invasive surgical options are available with acceptable outcomes though open ureteroneocystostomy still carries the highest success rate.

12.
Kidney Int ; 90(3): 568-79, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27401534

RESUMEN

Diabetes mellitus is a systemic disease associated with a deficiency of insulin production or action. Diabetic patients have an increased susceptibility to infection with the urinary tract being the most common site. Recent studies suggest that Ribonuclease 7 (RNase 7) is a potent antimicrobial peptide that plays an important role in protecting the urinary tract from bacterial insult. Because the impact of diabetes on RNase 7 expression and function are unknown, we investigated the effects of insulin on RNase 7 using human urine specimens. The urinary RNase 7 concentrations were measured in healthy control patients and insulin-deficient type 1 diabetics before and after starting insulin therapy. Compared with controls, diabetic patients had suppressed urinary RNase 7 concentrations, which increased with insulin. Using primary human urothelial cells, the mechanisms by which insulin stimulates RNase 7 synthesis were next explored. Insulin induced RNase 7 production via the phosphatidylinositide 3-kinase signaling pathway (PI3K/AKT) to shield urothelial cells from uropathogenic E. coli. In contrast, uropathogenic E. coli suppressed PI3K/AKT activity and RNase 7 production. Thus, insulin and PI3K/AKT signaling are essential for RNase 7 expression and increased infection risks in diabetic patients may be secondary to suppressed RNase 7 production. Our data may provide unique insight into novel urinary tract infection therapeutic strategies in at-risk populations.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Infecciones por Escherichia coli/metabolismo , Insulina/metabolismo , Ribonucleasas/metabolismo , Infecciones Urinarias/metabolismo , Sistema Urinario/metabolismo , Adolescente , Antígenos CD/metabolismo , Línea Celular Tumoral , Niño , Preescolar , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/orina , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/etiología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/orina , Femenino , Humanos , Insulina/uso terapéutico , Masculino , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasas/metabolismo , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor de Insulina/metabolismo , Ribonucleasas/orina , Transducción de Señal , Sistema Urinario/microbiología , Infecciones Urinarias/etiología , Infecciones Urinarias/microbiología , Infecciones Urinarias/orina
13.
Kidney Int ; 89(3): 612-24, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26880456

RESUMEN

Proper development and maintenance of urothelium is critical to its function. Uroplakins are expressed in developing and mature urothelium where they establish plaques associated with the permeability barrier. Their precise functional role in development and disease is unknown. Here, we disrupted Upk1b in vivo where its loss resulted in urothelial plaque disruption in the bladder and kidney. Upk1b(RFP/RFP) bladder urothelium appeared dysplastic with expansion of the progenitor cell markers, Krt14 and Krt5, increased Shh expression, and loss of terminal differentiation markers Krt20 and uroplakins. Upk1b(RFP/RFP) renal urothelium became stratified with altered cellular composition. Upk1b(RFP/RFP) mice developed age-dependent progressive hydronephrosis. Interestingly, 16% of Upk1b(RFP/RFP) mice possessed unilateral duplex kidneys. Our study expands the role of uroplakins, mechanistically links plaque formation to urinary tract development and function, and provides a tantalizing connection between congenital anomalies of the kidney and urinary tract along with functional deficits observed in a variety of urinary tract diseases. Thus, kidney and bladder urothelium are regionally distinct and remain highly plastic, capable of expansion through tissue-specific progenitor populations. Furthermore, Upk1b plays a previously unknown role in early kidney development representing a novel genetic target for congenital anomalies of the kidney and urinary tract.


Asunto(s)
Diferenciación Celular , Riñón/metabolismo , Tetraspaninas/metabolismo , Vejiga Urinaria/metabolismo , Urotelio/metabolismo , Animales , Proliferación Celular , Regulación del Desarrollo de la Expresión Génica , Genotipo , Homeostasis , Hidronefrosis/genética , Hidronefrosis/metabolismo , Riñón/anomalías , Riñón/ultraestructura , Ratones Noqueados , Fenotipo , Transducción de Señal , Tetraspaninas/deficiencia , Tetraspaninas/genética , Vejiga Urinaria/anomalías , Vejiga Urinaria/ultraestructura , Anomalías Urogenitales/genética , Anomalías Urogenitales/metabolismo , Uroplaquina Ib , Urotelio/anomalías , Urotelio/ultraestructura , Reflujo Vesicoureteral/genética , Reflujo Vesicoureteral/metabolismo
14.
Nat Rev Nephrol ; 11(11): 642-55, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26149835

RESUMEN

Urinary tract infections (UTIs), including pyelonephritis, are among the most common and serious infections encountered in nephrology practice. UTI risk is increased in selected patient populations with renal and urinary tract disorders. As the prevalence of antibiotic-resistant uropathogens increases, novel and alternative treatment options will be needed to reduce UTI-associated morbidity. Discoveries over the past decade demonstrate a fundamental role for the innate immune system in protecting the urothelium from bacterial challenge. Antimicrobial peptides, an integral component of this urothelial innate immune system, demonstrate potent bactericidal activity toward uropathogens and might represent a novel class of UTI therapeutics. The urothelium of the bladder and the renal epithelium secrete antimicrobial peptides into the urinary stream. In the kidney, intercalated cells--a cell-type involved in acid-base homeostasis--have been shown to be an important source of antimicrobial peptides. Intercalated cells have therefore become the focus of new investigations to explore their function during pyelonephritis and their role in maintaining urinary tract sterility. This Review provides an overview of UTI pathogenesis in the upper and lower urinary tract. We describe the role of intercalated cells and the innate immune response in preventing UTI, specifically highlighting the role of antimicrobial peptides in maintaining urinary tract sterility.


Asunto(s)
Riñón/inmunología , Péptidos/fisiología , Infecciones Urinarias/inmunología , Catelicidinas/fisiología , Defensinas/fisiología , Infecciones por Escherichia coli/inmunología , Humanos , Inmunidad Innata , Pielonefritis/microbiología , Ribonucleasas/fisiología , Escherichia coli Uropatógena
15.
Proc Natl Acad Sci U S A ; 112(16): 5105-10, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25848046

RESUMEN

The dietary change resulting from the domestication of plant and animal species and development of agriculture at different locations across the world was one of the most significant changes in human evolution. An increase in dietary carbohydrates caused an increase in dental caries following the development of agriculture, mediated by the cariogenic oral bacterium Streptococcus mutans. Salivary agglutinin [SAG, encoded by the deleted in malignant brain tumors 1 (DMBT1) gene] is an innate immune receptor glycoprotein that binds a variety of bacteria and viruses, and mediates attachment of S. mutans to hydroxyapatite on the surface of the tooth. In this study we show that multiallelic copy number variation (CNV) within DMBT1 is extensive across all populations and is predicted to result in between 7-20 scavenger-receptor cysteine-rich (SRCR) domains within each SAG molecule. Direct observation of de novo mutation in multigeneration families suggests these CNVs have a very high mutation rate for a protein-coding locus, with a mutation rate of up to 5% per gamete. Given that the SRCR domains bind S. mutans and hydroxyapatite in the tooth, we investigated the association of sequence diversity at the SAG-binding gene of S. mutans, and DMBT1 CNV. Furthermore, we show that DMBT1 CNV is also associated with a history of agriculture across global populations, suggesting that dietary change as a result of agriculture has shaped the pattern of CNV at DMBT1, and that the DMBT1-S. mutans interaction is a promising model of host-pathogen-culture coevolution in humans.


Asunto(s)
Evolución Biológica , Genética de Población , Tasa de Mutación , Mutación/genética , Receptores de Superficie Celular/genética , Agricultura , Secuencia de Aminoácidos , Proteínas de Unión al Calcio , Variaciones en el Número de Copia de ADN/genética , Proteínas de Unión al ADN , Humanos , Ligandos , Datos de Secuencia Molecular , Receptores de Superficie Celular/química , Streptococcus mutans/metabolismo , Proteínas Supresoras de Tumor
16.
J Infect Dis ; 211(9): 1418-28, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25367299

RESUMEN

BACKGROUND: Nonstructural protein 1 (NS1) proteins from avian influenza viruses like the 1918 pandemic NS1 are capable of inhibiting the key signaling integrator c-Abl (Abl1), resulting in massive cytopathic cell alterations. METHODS: In the current study, we addressed the consequences of NS1-mediated alteration of c-Abl on acute lung injury and pathogenicity in an in vivo mouse model. RESULTS: Comparing isogenic strains that differ only in their ability to inhibit c-Abl, we observed elevated pathogenicity for the c-Abl-inhibiting virus. NS1-mediated blockade of c-Abl resulted in severe lung pathology and massive edema formation and facilitated secondary bacterial pneumonia. This phenotype was independent of differences in replication and immune responses, defining it as an NS1 virulence mechanism distinct from its canonical functions. Microarray analysis revealed extensive downregulation of genes involved in cell integrity and vascular endothelial regulation. CONCLUSIONS: NS1 protein-mediated blockade of c-Abl signaling drives acute lung injury and primes for bacterial coinfections revealing potential insights into the pathogenicity of the 1918 pandemic virus.


Asunto(s)
Lesión Pulmonar Aguda/etiología , Infecciones Bacterianas/etiología , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Influenza Pandémica, 1918-1919 , Infecciones por Orthomyxoviridae/virología , Proteínas Proto-Oncogénicas c-abl/metabolismo , Proteínas no Estructurales Virales/metabolismo , Lesión Pulmonar Aguda/complicaciones , Lesión Pulmonar Aguda/patología , Animales , Biomarcadores , Humanos , Pulmón/patología , Pulmón/virología , Ratones , Proteínas Proto-Oncogénicas c-abl/genética
17.
PLoS One ; 8(10): e77714, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24204930

RESUMEN

Beta defensins (BDs) are cationic peptides with antimicrobial activity that defend epithelial surfaces including the skin, gastrointestinal, and respiratory tracts. However, BD expression and function in the urinary tract are incompletely characterized. The purpose of this study was to describe Beta Defensin-1 (BD-1) expression in the lower urinary tract, regulation by cystitis, and antimicrobial activity toward uropathogenic Escherichia coli (UPEC) in vivo. Human DEFB1 and orthologous mouse Defb1 mRNA are detectable in bladder and ureter homogenates, and human BD-1 protein localizes to the urothelium. To determine the relevance of BD-1 to lower urinary tract defense in vivo, we evaluated clearance of UPEC by Defb1 knockout (Defb1(-/-)) mice. At 6, 18, and 48 hours following transurethral UPEC inoculation, no significant differences were observed in bacterial burden in bladders or kidneys of Defb1(-/-) and wild type C57BL/6 mice. In wild type mice, bladder Defb1 mRNA levels decreased as early as two hours post-infection and reached a nadir by six hours. RT-PCR profiling of BDs identified expression of Defb3 and Defb14 mRNA in murine bladder and ureter, which encode for mBD-3 and mBD-14 protein, respectively. MBD-14 protein expression was observed in bladder urothelium following UPEC infection, and both mBD-3 and mBD-14 displayed dose-dependent bactericidal activity toward UPEC in vitro. Thus, whereas mBD-1 deficiency does not alter bladder UPEC burden in vivo, we have identified mBD-3 and mBD-14 as potential mediators of mucosal immunity in the lower urinary tract.


Asunto(s)
Antiinfecciosos/metabolismo , Sistema Urinario/metabolismo , Sistema Urinario/microbiología , beta-Defensinas/genética , beta-Defensinas/metabolismo , Animales , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/prevención & control , Femenino , Humanos , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Noqueados , Escherichia coli Uropatógena/metabolismo
18.
Urology ; 81(5): 943-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23523293

RESUMEN

OBJECTIVE: To characterize the clinical course after cutaneous vesicostomy (CV) in megabladder (mgb(-/-)) mice with functional urinary bladder obstruction. MATERIALS AND METHODS: A total of 45 mgb(-/-) male mice underwent CV at a median age of 25 days. The 34 mice that survived >3 days after CV were evaluated by serial observation and renal ultrasonography. The moribund mice were killed. The urinary bladders and kidneys were analyzed by histopathologic analysis, and urine biochemical studies were performed. RESULTS: At a median duration of 11 weeks after CV, 35% of mgb(-/-) male mice (12 of 34) had become moribund with pelvic masses, which were identified as bladder stones at necropsy. The urine pH was alkaline, and microscopic examination demonstrated struvite crystals. The urine samples contained Gram-positive cocci, and the urine cultures were polymicrobial. The stone composition was chiefly struvite (88%-94%) admixed with calcium phosphate. In 40% of cases (2 of 5), retained intravesical polypropylene suture was identified as the presumed nidus. No stones were detected in >100 male mice before CV or in 25 cases when CV was performed using polydioxanone suture. The kidneys from 33% of the mice (4/12) with bladder stones contained staghorn calculi. The histopathologic findings from the mice with struvite stones demonstrated active cystitis, pyelitis, and chronic pyelonephritis. CONCLUSION: These findings attest to the importance of the nidus in lithogenesis and provide a novel murine model for struvite urolithiasis and chronic infection of the diverted urinary tract.


Asunto(s)
Complicaciones Posoperatorias , Derivación Urinaria/efectos adversos , Infecciones Urinarias/etiología , Urolitiasis/etiología , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Transgénicos , Ultrasonografía , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/patología , Infecciones Urinarias/diagnóstico por imagen , Urolitiasis/diagnóstico por imagen
19.
J Pediatr Urol ; 8(1): 72-6, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21126919

RESUMEN

OBJECTIVE: Physicians often defer obtaining a voiding cystourethrogram (VCUG) after the diagnosis of urinary tract infection (UTI) due to concerns regarding increased health risks and inflated rates of vesicoureteral reflux (VUR). This study examines the health risks and accuracy of VCUG testing after diagnosis of a febrile UTI. PATIENTS AND METHODS: A retrospective review was conducted of children aged 0-18 years admitted to Nationwide Children's Hospital with a febrile UTI in 1995-2000. Children were divided into two cohorts - those who had a VCUG performed within 1 week of diagnosis (early VCUG cohort) and those who had a VCUG performed more than 1 week after diagnosis (late VCUG cohort). All children were followed for an additional 5 years after hospital discharge. RESULTS: The incidence and severity of VUR were similar in patients that underwent early and late VCUG testing. Patients who underwent early VCUG testing showed no sign of worsening illness after the test was performed. During the 5-year follow up, these patients did not have higher rates of return emergency department visits or hospital readmission compared to those who received late VCUG testing. CONCLUSIONS: The rate of VUR detection does not increase with early VCUG testing. Early VCUG testing does not lead to increased risk of bacterial dissemination or urosepsis.


Asunto(s)
Uretra/diagnóstico por imagen , Vejiga Urinaria/diagnóstico por imagen , Infecciones Urinarias/diagnóstico por imagen , Urografía/efectos adversos , Urografía/estadística & datos numéricos , Reflujo Vesicoureteral/epidemiología , Adolescente , Distribución por Edad , Causalidad , Niño , Preescolar , Estudios de Cohortes , Femenino , Fiebre/diagnóstico , Estudios de Seguimiento , Indicadores de Salud , Humanos , Incidencia , Lactante , Masculino , Seguridad del Paciente , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Distribución por Sexo , Estadísticas no Paramétricas , Factores de Tiempo , Infecciones Urinarias/microbiología , Micción , Urografía/métodos , Reflujo Vesicoureteral/etiología , Reflujo Vesicoureteral/fisiopatología
20.
Pediatr Nephrol ; 26(8): 1269-73, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21597971

RESUMEN

Prune belly syndrome (PBS) is a congenital anomaly characterized by the clinical triad of lax abdominal musculature, bilateral cryptorchidism, and abnormalities of the kidney and urinary tract. Previous reports of malignancy in patients with PBS have been limited to germ cell tumors. Hepatoblastoma (HBL) is the most common hepatic malignancy of childhood, affecting approximately 100 children each year in the USA. We describe a set of 4 pediatric patients with PBS and HBL. All individuals were born after 2002. These subjects lacked genetic, natal, or environmental factors known to confer risk of HBL. The occurrence of PBS and HBL in these patients constitutes a novel potential association.


Asunto(s)
Hepatoblastoma/complicaciones , Neoplasias Hepáticas/complicaciones , Síndrome del Abdomen en Ciruela Pasa/complicaciones , Preescolar , Humanos , Lactante , Recién Nacido , Masculino
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