Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 24
Filter
1.
JCI Insight ; 9(3)2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38127456

ABSTRACT

Despite clinical use of immunosuppressive agents, the immunopathogenesis of minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) remains unclear. Src homology 3-binding protein 2 (SH3BP2), a scaffold protein, forms an immune signaling complex (signalosome) with 17 other proteins, including phospholipase Cγ2 (PLCγ2) and Rho-guanine nucleotide exchange factor VAV2 (VAV2). Bioinformatic analysis of human glomerular transcriptome (Nephrotic Syndrome Study Network cohort) revealed upregulated SH3BP2 in MCD and FSGS. The SH3BP2 signalosome score and downstream MyD88, TRIF, and NFATc1 were significantly upregulated in MCD and FSGS. Immune pathway activation scores for Toll-like receptors, cytokine-cytokine receptor, and NOD-like receptors were increased in FSGS. Lower SH3BP2 signalosome score was associated with MCD, higher estimated glomerular filtration rate, and remission. Further work using Sh3bp2KI/KI transgenic mice with a gain-in-function mutation showed ~6-fold and ~25-fold increases in albuminuria at 4 and 12 weeks, respectively. Decreased serum albumin and unchanged serum creatinine were observed at 12 weeks. Sh3bp2KI/KI kidney morphology appeared normal except for increased mesangial cellularity and patchy foot process fusion without electron-dense deposits. SH3BP2 co-immunoprecipitated with PLCγ2 and VAV2 in human podocytes, underscoring the importance of SH3BP2 in immune activation. SH3BP2 and its binding partners may determine the immune activation pathways resulting in podocyte injury leading to loss of the glomerular filtration barrier.


Subject(s)
Glomerulosclerosis, Focal Segmental , Nephrosis, Lipoid , Nephrotic Syndrome , Animals , Humans , Mice , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Glomerulosclerosis, Focal Segmental/genetics , Glomerulosclerosis, Focal Segmental/metabolism , Kidney/pathology , Kidney Glomerulus/pathology , Mice, Transgenic , Nephrosis, Lipoid/pathology , Nephrotic Syndrome/metabolism , Phospholipase C gamma/genetics , Phospholipase C gamma/metabolism
2.
FASEB J ; 36(10): e22559, 2022 10.
Article in English | MEDLINE | ID: mdl-36125047

ABSTRACT

Increased fluid-flow shear stress (FFSS) contributes to hyperfiltration-induced podocyte and glomerular injury resulting in progression of chronic kidney disease (CKD). We reported that increased FFSS in vitro and in vivo upregulates PGE2 receptor EP2 (but not EP4 expression), COX2-PGE2 -EP2 axis, and EP2-linked Akt-GSK3ß-ß-catenin signaling pathway in podocytes. To understand and use the disparities between PGE2 receptors, specific agonists, and antagonists of EP2 and EP4 were used to assess phosphorylation of Akt, GSK3ß and ß-catenin in podocytes using Western blotting, glomerular filtration barrier function using in vitro albumin permeability (Palb ) assay, and mitigation of hyperfiltration-induced injury in unilaterally nephrectomized (UNX) mice at 1 and 6 months. Results show an increase in Palb by PGE2 , EP2 agonist (EP2AGO ) and EP4 antagonist (EP4ANT ), but not by EP2 antagonist (EP2ANT ) or EP4 agonist (EP4AGO ). Pretreatment with EP2ANT blocked the effect of PGE2 or EP2AGO on Palb . Modulation of EP2 and EP4 also induced opposite effects on phosphorylation of Akt and ß-Catenin. Individual agonists or antagonists of EP2 or EP4 did not induce significant improvement in albuminuria in UNX mice. However, treatment with a combination EP2ANT + EP4AGO for 1 or 6 months caused a robust decrease in albuminuria. EP2ANT + EP4AGO combination did not impact adaptive hypertrophy or increased serum creatinine. Observed differences between expression of EP2 and EP4 on the glomerular barrier highlight these receptors as potential targets for intervention. Safe and effective mitigating effect of EP2ANT + EP4AGO presents a novel opportunity to delay the progression of hyperfiltration-associated CKD as seen in transplant donors.


Subject(s)
Receptors, Prostaglandin E, EP2 Subtype , Renal Insufficiency, Chronic , Albumins , Albuminuria , Animals , Creatinine , Cyclooxygenase 2 , Dinoprostone/metabolism , Glycogen Synthase Kinase 3 beta , Gonadal Steroid Hormones , Mice , Proto-Oncogene Proteins c-akt , Receptors, Prostaglandin E, EP2 Subtype/metabolism , Receptors, Prostaglandin E, EP4 Subtype , beta Catenin
4.
Sci Rep ; 11(1): 13260, 2021 06 24.
Article in English | MEDLINE | ID: mdl-34168254

ABSTRACT

Systemic inflammation in pregnant obese women is associated with 1.5- to 2-fold increase in serum Interleukin-6 (IL-6) and newborns with lower kidney/body weight ratio but the role of IL-6 in increased susceptibility to chronic kidney (CKD) in adult progeny is not known. Since IL-6 crosses the placental barrier, we administered recombinant IL-6 (10 pg/g) to pregnant mice starting at mid-gestation yielded newborns with lower body (p < 0.001) and kidney (p < 0.001) weights. Histomorphometry indicated decreased nephrogenic zone width (p = 0.039) with increased numbers of mature glomeruli (p = 0.002) and pre-tubular aggregates (p = 0.041). Accelerated maturation in IL-6 newborns was suggested by early expression of podocyte-specific protein podocin in glomeruli, increased 5-methyl-cytosine (LC-MS analysis for CpG DNA methylation) and altered expression of certain genes of cell-cycle and apoptosis (RT-qPCR array-analysis). Western blotting showed upregulated pJAK2/pSTAT3. Thus, treating dams with IL-6 as a surrogate provides newborns to study effects of maternal systemic inflammation on future susceptibility to CKD in adulthood.


Subject(s)
Interleukin-6/adverse effects , Prenatal Exposure Delayed Effects/chemically induced , Animals , Animals, Newborn/growth & development , Apoptosis/drug effects , Birth Weight/drug effects , Cell Cycle/drug effects , Female , Kidney/growth & development , Kidney/metabolism , Kidney/pathology , Male , Mice , Mice, Inbred C57BL , Organ Size/drug effects , Pregnancy , Prenatal Exposure Delayed Effects/pathology
5.
Cells ; 10(5)2021 05 19.
Article in English | MEDLINE | ID: mdl-34069476

ABSTRACT

Increased fluid flow shear stress (FFSS) in solitary kidney alters podocyte function in vivo. FFSS-treated cultured podocytes show upregulated AKT-GSK3ß-ß-catenin signaling. The present study was undertaken to confirm (i) the activation of ß-catenin signaling in podocytes in vivo using unilaterally nephrectomized (UNX) TOPGAL mice with the ß-galactosidase reporter gene for ß-catenin activation, (ii) ß-catenin translocation in FFSS-treated mouse podocytes, and (iii) ß-catenin signaling using publicly available data from UNX mice. The UNX of TOPGAL mice resulted in glomerular hypertrophy and increased the mesangial matrix consistent with hemodynamic adaptation. Uninephrectomized TOPGAL mice showed an increased ß-galactosidase expression at 4 weeks but not at 12 weeks, as assessed using immunofluorescence microscopy (p < 0.001 at 4 weeks; p = 0.16 at 12 weeks) and X-gal staining (p = 0.008 at 4 weeks; p = 0.65 at 12 weeks). Immunofluorescence microscopy showed a significant increase in phospho-ß-catenin (Ser552, p = 0.005) at 4 weeks but not at 12 weeks (p = 0.935) following UNX, and the levels of phospho-ß-catenin (Ser675) did not change. In vitro FFSS caused a sustained increase in the nuclear translocation of phospho-ß-catenin (Ser552) but not phospho-ß-catenin (Ser675) in podocytes. The bioinformatic analysis of the GEO dataset, #GSE53996, also identified ß-catenin as a key upstream regulator. We conclude that transcription factor ß-catenin mediates FFSS-induced podocyte (glomerular) injury in solitary kidney.


Subject(s)
Glomerular Filtration Rate , Mechanotransduction, Cellular , Podocytes/metabolism , Solitary Kidney/metabolism , beta Catenin/metabolism , Animals , Cell Line , Databases, Genetic , Disease Models, Animal , Genes, fos , Lac Operon , Lymphoid Enhancer-Binding Factor 1/genetics , Mice, Transgenic , Podocytes/pathology , Promoter Regions, Genetic , Solitary Kidney/genetics , Solitary Kidney/pathology , Solitary Kidney/physiopathology , Stress, Mechanical , Transcription Factor 3/genetics , beta Catenin/genetics
6.
Am J Physiol Renal Physiol ; 319(2): F312-F322, 2020 08 01.
Article in English | MEDLINE | ID: mdl-32628542

ABSTRACT

The ultrafiltrate flow over the major processes and cell body generates fluid flow shear stress (FFSS) on podocytes. Hyperfiltration-associated increase in FFSS can lead to podocyte injury and detachment. Previously, we showed that FFSS-induced upregulation of the cyclooxygenase 2 (COX2)-PGE2-prostaglandin E receptor 2 (EP2) axis in podocytes activates Akt-glycogen synthase kinase-3ß-ß-catenin and MAPK/ERK signaling in response to FFSS. Integrative MultiOmics Pathway Resolution (IMPRes) is a new bioinformatic tool that enables simultaneous time-series analysis of more than two groups to identify pathways and molecular connections. In the present study, we used previously characterized COX2 [prostaglandin-endoperoxide synthase 2 (Ptgs2)], EP2 (Ptger2), and ß1-catenin (Ctnnb1) as "seed genes" from an array data set of four groups analyzed over a time course. The 3 seed genes shared 7 pathways and 50 genes of 14 pathways and 89 genes identified by IMPRes. A composite of signaling pathways highlighted the temporal molecular connections during mechanotransduction signaling in FFSS-treated podocytes. We investigated the "proteoglycans in cancer" and "galactose metabolism" pathways predicted by IMPRes. A custom-designed PCR array validated 60.7% of the genes predicted by IMPRes analysis, including genes for the above-named pathways. Further validation using Western blot analysis showed increased expression of phosho-Erbb2, phospho-mammalian target of rapamycin (mTOR), CD44, and hexokinase II (Hk2); decreased total Erbb2, galactose mutarotase (Galm), and ß-1,4-galactosyltransferase 1 (B4galt1); and unchanged total mTOR and AKT3. These findings corroborate our previously reported results. This study demonstrates the potential of the IMPRes method to identify novel pathways. Identifying the "proteoglycans in cancer" and "galactose metabolism" pathways has generated a lead to study the significance of FFSS-induced glycocalyx remodeling and possible detachment of podocytes from the glomerular matrix.


Subject(s)
Podocytes/metabolism , Proteoglycans/metabolism , Receptors, Prostaglandin E, EP2 Subtype/metabolism , Stress, Mechanical , Transcriptional Activation/physiology , Cyclooxygenase 2/metabolism , Kidney Glomerulus/metabolism , Mechanotransduction, Cellular/physiology , TOR Serine-Threonine Kinases/metabolism , Up-Regulation
7.
J Clin Pathol ; 73(9): 563-570, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31964683

ABSTRACT

AIMS: Historically, there has been no consensus on the diagnostic classification of high-grade B-cell lymphoma (HGBCL) with morphological features of Burkitt lymphoma (BL) but no MYC gene rearrangement (MYC-negative). The 2016 WHO classification of tumours of haematopoietic and lymphoid tissues has shed some light on this field with the modification of the grey-zone lymphoma with features intermediate between BL and diffuse large B-cell lymphoma, and the creation of several new entities. The aim of this study was to investigate how the revised WHO classification affects our practice in diagnosing these lymphomas in children. METHODS: We retrospectively reviewed cases of mature HGBCL diagnosed at our hospital between 2015 and 2018. RESULTS: Among 14 mature HGBCL cases with BL morphological features, 11 showed MYC rearrangement consistent with BL and 3 were MYC-negative. Two MYC-negative cases showed regions of 11q gain and loss by microarray consistent with Burkitt-like lymphoma with 11q aberration (BLL-11q). The third MYC-negative case showed diffuse and strong MUM1 expression, translocation involving 6p25 by chromosome analysis and IRF4 rearrangement by fluorescence in situ hybridisation analysis consistent with large B-cell lymphoma with IRF4 rearrangement (LBL-IRF4). All patients were treated according to applicable chemotherapeutic protocols and achieved remission. CONCLUSIONS: BLL-11q and LBL-IRF4, two newly defined entities, should be considered in paediatric MYC-negative mature HGBCL cases. Accurate diagnosis needs careful histopathological examination and proper cytogenetic testing. Since they have unique cytogenetic features, specific treatments for them may emerge in the future. Therefore, accurate diagnosis based on the 2016 WHO classification is clinically significant.


Subject(s)
Burkitt Lymphoma/classification , Chromosome Aberrations , Lymphoma, Large B-Cell, Diffuse/classification , Translocation, Genetic , Burkitt Lymphoma/genetics , Burkitt Lymphoma/pathology , Child , Child, Preschool , Cytogenetics , Female , Humans , In Situ Hybridization, Fluorescence , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/pathology , Male , Retrospective Studies
8.
J Pediatr Gastroenterol Nutr ; 69(6): 668-672, 2019 12.
Article in English | MEDLINE | ID: mdl-31765335

ABSTRACT

BACKGROUND: Juvenile polyps (JPs) are the most common gastrointestinal polyps diagnosed in children. There is paucity of evidence differentiating polyp burden groups and the presence and significance of neoplastic changes. METHODS: A retrospective chart review of patients, ages birth through 18 years with nonsyndromic JPs was performed from 2003 to 2017. Abstracted data included basic demographics, age, clinical presentation, colonoscopy findings, and pathology report. Slides of polyps with neoplasia were reviewed by a pathologist. RESULTS: A total of 213 subjects underwent 326 procedures and 435 polypectomies. Subjects with positive family history, positive gene mutations, or numerous (>10) polyps were excluded. Groups were defined by polyp number (1, 2-4, 5-10). Polyp recurrence on repeat colonoscopy was significantly related to polyp burden (1 polyp: 1.5%/2-4 polyps 19.2%/5-10 polyps 82.6%: P < 0.001). Polyp distribution was significantly different amongst different groups with isolated polyps favoring a distal distribution. JPs harboring adenomatous foci were reported in 26 (12%) patients. JPs harboring adenomatous foci were significantly more likely to be proximally distributed but the presence of adenomatous transformation within the polyps did not correlate with polyp number or the likelihood of polyp recurrence on repeat colonoscopy. CONCLUSIONS: JP recurrence is positively and significantly related to polyp burden. JP harbored adenomatous changes independent of polyp number, underscoring a possible malignant potential in JPs. In the absence of a consistent genotype or pedigree, the presence of adenomatous transformation within JPs cannot be construed as a biomarker for syndromic juvenile polyposis.


Subject(s)
Colonic Polyps/diagnosis , Intestinal Polyposis/congenital , Neoplastic Syndromes, Hereditary/diagnosis , Child , Child, Preschool , Colonic Polyps/complications , Colonic Polyps/physiopathology , Colonoscopy/statistics & numerical data , Disease Progression , Female , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Neoplasms/etiology , Humans , Intestinal Polyposis/complications , Intestinal Polyposis/diagnosis , Intestinal Polyposis/physiopathology , Male , Neoplasm Recurrence, Local/etiology , Neoplastic Syndromes, Hereditary/complications , Neoplastic Syndromes, Hereditary/physiopathology , Retrospective Studies
9.
Pathol Res Pract ; 215(10): 152550, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31351802

ABSTRACT

When Spitz nevi have increased vertical thickness (>1.0 mm), show ulceration and deep seated mitoses, the differential diagnostic considerations of atypical Spitz tumor (AST) or a Spitzoid melanoma (SM) enter into consideration. While molecular genetic testing could be employed in the work up of atypical melanocytic proliferations, they are expensive and not available at all institutions. Recently, one study employed the combination of p16, Ki-67 and HMB45 (PKH) immunohistochemistry on adult melanomas and proposed a combination of the three markers with scoring of their result to support a diagnosis of melanoma. We report the utility of this antibody combination scoring in discriminating SM and AST in children. We retrospectively reviewed 30 Spitzoid lesions (7 SM, 9 AST and 14 Spitz nevi) from children. Slides from H&E staining and Immunohistochemistry for p16, Ki-67 and HMB45 were reviewed for all cases. The extent of immunohistochemical expression in the lesional cells was scored following published criteria as follows: p16 scored as 0, 1, 2, 3; Ki-67 scored as 0, 1, 2, 3, 4 and HMB45 scored as 0, 1 and 2. Thus, the total PKH score for the combination of the 3 antibodies for any case could vary from 0 to 9. The result of the immunohistochemical analysis of cases in our study revealed that the PKH score of Spitz nevus and AST was below 4 for each of the case and that of SM was >4 for each of the case. These results are significant as the previously published study found that the PKH score of equal/or >4 correlated with melanoma and less <4 correlated with benign nevi. Independently, the immunostains could be misleading as Ki-67 labeling index tended to be higher in young children (<2 years of age) and HMB45 was occasionally negative in both AST and SM, and p16 could be completely lost in AST. Our study replicates the findings of the published study of adult melanomas and nevi that showed a total PKH score of equal/or>4 is seen in melanoma. Although, the number of SM cases in our study are few, the PKH scoring pattern of malignant and benign cases was congruent with the adult study. We suggest routine use of PKH immunohistochemistry in the work up of atypical Spitzoid lesions in children.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p16/metabolism , Ki-67 Antigen/metabolism , Melanoma-Specific Antigens/metabolism , Melanoma/diagnosis , Nevus, Epithelioid and Spindle Cell/diagnosis , Skin Neoplasms/diagnosis , Biomarkers, Tumor/metabolism , Cell Differentiation , Diagnosis, Differential , Humans , Immunohistochemistry , Melanoma/metabolism , Melanoma/pathology , Nevus, Epithelioid and Spindle Cell/metabolism , Nevus, Epithelioid and Spindle Cell/pathology , Retrospective Studies , Skin/metabolism , Skin/pathology , Skin Neoplasms/metabolism , Skin Neoplasms/pathology , gp100 Melanoma Antigen
10.
J Pediatr Hematol Oncol ; 41(8): 586-595, 2019 11.
Article in English | MEDLINE | ID: mdl-30973487

ABSTRACT

Neuroblastoma (NB) in children older than 10 years is rare. We reviewed our archives for patients with NB aged 10 to 18 years and summarized their clinicopathologic/genetic records. Of 96 patients, 4 patients were identified in this age group. Four tumors were abdominal; 1 patient had 2 tumors at diagnosis, one of which was presacral. Tumor sizes ranged from 3 to 20 cm. All tumors were high risk at clinical stages 3 and 4, with metastasis to bone marrow and other areas. Four tumors were poorly differentiated with unfavorable histology and one patient with bilateral adrenal disease had an intermixed ganglioneuroblastoma on one side. Another tumor exhibited pheochromocytoma-like morphology. MYCN amplification was present in bone marrow metastasis in one case. Complex chromosomal gains and 19p deletions were common. Exome sequencing revealed ALK variants in 2 cases and previously unreported MAGI2, RUNX1, and MLL mutations. All patients received standard chemotherapy and 2 patients received ALK-targeted trial therapy. Three patients died of disease, ranging 18 to 23 months after diagnosis. One patient has active disease and is receiving trial therapy. In conclusion, NB in children older than 10 years may exhibit unusual clinicopathologic and genetic features with large tumors, bilateral adrenal disease, rare morphologic features, complex DNA microarray findings and novel mutations. Patients often have grim prognoses despite genomic profiling-guided targeted therapy.


Subject(s)
Antineoplastic Agents/administration & dosage , Neoplasm Proteins/genetics , Neuroblastoma , Adolescent , Child , Female , Humans , Male , Neoplasm Metastasis , Neoplasm Staging , Neuroblastoma/diagnosis , Neuroblastoma/drug therapy , Neuroblastoma/genetics , Neuroblastoma/pathology , Prognosis
11.
Am J Physiol Renal Physiol ; 314(1): F22-F34, 2018 01 01.
Article in English | MEDLINE | ID: mdl-28877882

ABSTRACT

Recently, we and others have found that hyperfiltration-associated increase in biomechanical forces, namely, tensile stress and fluid flow shear stress (FFSS), can directly and distinctly alter podocyte structure and function. The ultrafiltrate flow over the major processes and cell body generates FFSS to podocytes. Our previous work suggests that the cyclooxygenase-2 (COX-2)-PGE2-PGE2 receptor 2 (EP2) axis plays an important role in mechanoperception of FFSS in podocytes. To address mechanotransduction of the perceived stimulus through EP2, cultured podocytes were exposed to FFSS (2 dyn/cm2) for 2 h. Total RNA from cells at the end of FFSS treatment, 2-h post-FFSS, and 24-h post-FFSS was used for whole exon array analysis. Differentially regulated genes ( P < 0.01) were analyzed using bioinformatics tools Enrichr and Ingenuity Pathway Analysis to predict pathways/molecules. Candidate pathways were validated using Western blot analysis and then further confirmed to be resulting from a direct effect of PGE2 on podocytes. Results show that FFSS-induced mechanotransduction as well as exogenous PGE2 activate the Akt-GSK3ß-ß-catenin (Ser552) and MAPK/ERK but not the cAMP-PKA signal transduction cascades. These pathways are reportedly associated with FFSS-induced and EP2-mediated signaling in other epithelial cells as well. The current regimen for treating hyperfiltration-mediated injury largely depends on targeting the renin-angiotensin-aldosterone system. The present study identifies specific transduction mechanisms and provides novel information on the direct effect of FFSS on podocytes. These results suggest that targeting EP2-mediated signaling pathways holds therapeutic significance for delaying progression of chronic kidney disease secondary to hyperfiltration.


Subject(s)
Dinoprostone/metabolism , Mechanotransduction, Cellular/physiology , Podocytes/cytology , Receptors, Prostaglandin E, EP2 Subtype/metabolism , Stress, Mechanical , Animals , Female , Mice , Renal Insufficiency, Chronic/therapy , Signal Transduction/physiology
12.
Pediatr Dev Pathol ; 18(2): 164-6, 2015.
Article in English | MEDLINE | ID: mdl-25569144

ABSTRACT

We describe a case of a 5-year-old girl with onchocerciasis. The patient was recently adopted from Ethiopia and presented with a firm, raised nodule on the midportion of the forehead. Initially, Langerhans cell histiocytosis with bone involvement was suspected; however, histopathologic analysis of the excised nodule revealed the presence of a young-adult, female Onchocerca volvulus worm. This case exemplifies the importance of recognizing the key morphologic characteristics of adult O. volvulus worms isolated from pediatric patients in nonendemic areas to ensure adroit clinical management.


Subject(s)
Onchocerca/isolation & purification , Onchocerciasis/parasitology , Subcutaneous Tissue/parasitology , Animals , Antiparasitic Agents/therapeutic use , Biopsy , Child, Preschool , Female , Forehead , Humans , Immunohistochemistry , Ivermectin/therapeutic use , Onchocerciasis/diagnosis , Onchocerciasis/therapy , Predictive Value of Tests , Subcutaneous Tissue/pathology , Treatment Outcome
13.
Am J Physiol Renal Physiol ; 307(12): F1323-33, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25234310

ABSTRACT

Hyperfiltration subjects podocytes to increased tensile stress and fluid flow shear stress (FFSS). We showed a 1.5- to 2.0-fold increase in FFSS in uninephrectomized animals and altered podocyte actin cytoskeleton and increased synthesis of prostaglandin E2 (PGE2) following in vitro application of FFSS. We hypothesized that increased FFSS mediates cellular changes through specific receptors of PGE2. Presently, we studied the effect of FFSS on cultured podocytes and decapsulated isolated glomeruli in vitro, and on solitary kidney in uninephrectomized sv129 mice. In cultured podocytes, FFSS resulted in increased gene and protein expression of cyclooxygenase (COX)-2 but not COX-1, prostanoid receptor EP2 but not EP4, and increased synthesis and secretion of PGE2, which were effectively blocked by indomethacin. Next, we developed a special flow chamber for applying FFSS to isolated glomeruli to determine its effect on an intact glomerular filtration barrier by measuring change in albumin permeability (Palb) in vitro. FFSS caused an increase in Palb that was blocked by indomethacin (P < 0.001). Finally, we show that unilateral nephrectomy in sv129 mice resulted in glomerular hypertrophy (P = 0.006), increased glomerular expression of COX-2 (P < 0.001) and EP2 (P = 0.039), and increased urinary albumin excretion (P = 0.001). Activation of the COX-2-PGE2-EP2 axis appears to be a specific response to FFSS in podocytes and provides a mechanistic basis for alteration in podocyte structure and the glomerular filtration barrier, leading to albuminuria in hyperfiltration-mediated kidney injury. The COX-2-PGE2-EP2 axis is a potential target for developing specific interventions to ameliorate the effects of hyperfiltration-mediated kidney injury in the progression of chronic kidney disease.


Subject(s)
Cyclooxygenase 2/metabolism , Dinoprostone/metabolism , Kidney Glomerulus/blood supply , Kidney Glomerulus/enzymology , Receptors, Prostaglandin E, EP2 Subtype/metabolism , Renal Circulation , Renal Insufficiency, Chronic/enzymology , Albuminuria/enzymology , Albuminuria/physiopathology , Animals , Cell Line , Cyclooxygenase 2/genetics , Cyclooxygenase Inhibitors/pharmacology , Disease Models, Animal , Kidney Glomerulus/drug effects , Kidney Glomerulus/pathology , Male , Mice , Mice, 129 Strain , Nephrectomy , Podocytes/metabolism , Podocytes/pathology , RNA, Messenger/metabolism , Receptors, Prostaglandin E, EP2 Subtype/genetics , Renal Circulation/drug effects , Renal Insufficiency, Chronic/etiology , Renal Insufficiency, Chronic/genetics , Renal Insufficiency, Chronic/pathology , Renal Insufficiency, Chronic/physiopathology , Signal Transduction , Stress, Mechanical , Time Factors , Up-Regulation
14.
Pediatr Surg Int ; 30(5): 565-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24557155

ABSTRACT

Histologically confirmed polyorchidism is an uncommon condition. The majority of cases are asymptomatic and associated with inguinal hernia or cryptorchidism. There are few reported cases of pediatric supernumerary testis presenting with testicular torsion. We present a case of missed torsion with incidentally detected triorchidism as well as an overview of pediatric polyorchidism.


Subject(s)
Cryptorchidism/diagnostic imaging , Cryptorchidism/surgery , Spermatic Cord Torsion/diagnostic imaging , Spermatic Cord Torsion/surgery , Testis/diagnostic imaging , Adolescent , Cryptorchidism/complications , Follow-Up Studies , Humans , Incidental Findings , Male , Spermatic Cord Torsion/complications , Ultrasonography
15.
Pediatr Dev Pathol ; 16(5): 372-7, 2013.
Article in English | MEDLINE | ID: mdl-23688346

ABSTRACT

A diffuse, infiltrating abdominal mass accompanied with fever and anemia in a child raises the possibility of a benign or malignant tumor, pseudotumor, or infection. Herein, we describe a 9-year-old girl and a 14-year-old boy with multiple large abdominal masses, fever, weight loss, and anemia. During the evaluation of the children, the girl was found to be immunocompetent, while the boy was found to be immunocompromised. Computerized tomography of the abdomen in both cases demonstrated multiple large intra-abdominal masses. Tumors in the girl were composed of wide-spread necrotizing granulomas and necrosis with dystrophic calcifications. In the boy, non-necrotic, homogenous histiocytic infiltrates with rare multinucleated giant cells and lymphocytes were observed histologically. Review of histologic sections identified gram-positive, nonbranching acid-fast bacillary organisms in both cases. Diagnoses of Mycobacterium fortuitum (MF) and Mycobacterium avium-intracellulare complex (MAC) were confirmed by tissue microbiologic cultures in the girl and boy, respectively. The girl with MF infection was appropriately treated and is currently doing well. The boy with MAC was found to have human immunodeficiency virus infection/acquired immune deficiency syndrome (AIDS) and is currently undergoing AIDS treatment. These cases highlight the striking contrast between responses to nontuberculous mycobacteria infection based on immune status.


Subject(s)
Mycobacterium Infections, Nontuberculous/immunology , Mycobacterium avium-intracellulare Infection/immunology , Mycobacterium avium-intracellulare Infection/pathology , Mycobacterium fortuitum , Acquired Immunodeficiency Syndrome/complications , Adolescent , Child , Female , Humans , Male , Mycobacterium Infections, Nontuberculous/pathology , Mycobacterium avium-intracellulare Infection/etiology
16.
Am J Med Genet A ; 143A(22): 2635-41, 2007 Nov 15.
Article in English | MEDLINE | ID: mdl-17937443

ABSTRACT

Mutations involving elastic tissue proteins result in a broad spectrum of phenotypes affecting skin, skeleton, ocular and vascular structures, including tortuous blood vessels and cutis laxa. Here we report on a female newborn with apparently long fingers, aortic aneurysm, tortuous pulmonary arteries and mild generalized lax skin. She died at 27 days of age due to severe respiratory distress and inoperable systemic vascular abnormalities. Skin biopsy showed marked paucity and fragmentation of elastic fibers and autopsy revealed occlusion of the pulmonary artery. DNA analysis identified compound heterozygous mutations ((c.835C > T (p.R279C)/c.1070_1073dupCCGC) in fibulin-4, a recently recognized elastic fiber associated protein. Analyses of dermal fibroblasts from the patient indicated that fibulin-4 mRNAs with the 4-bp duplication transcribed from one allele are probably subject to nonsense-mediated decay, whereas synthesis and secretion of the missense R279C fibulin-4 protein from the other allele is severely impaired. Immunostaining demonstrated a total absence of fibulin-4 fibers in the extracellular matrix deposited by the patient's fibroblasts. Our studies provide evidence that deficiency in fibulin-4 leads to a perinatal lethal condition associated with elastic tissue abnormalities.


Subject(s)
Aortic Aneurysm/genetics , Arachnodactyly/genetics , Arterial Occlusive Diseases/genetics , Cutis Laxa/genetics , Extracellular Matrix Proteins/genetics , Abnormalities, Multiple , Aortic Aneurysm/etiology , Arachnodactyly/etiology , Arterial Occlusive Diseases/etiology , Cutis Laxa/etiology , Elastic Tissue/pathology , Extracellular Matrix Proteins/deficiency , Fatal Outcome , Female , Heterozygote , Humans , Infant, Newborn , Mutation , Pulmonary Artery
17.
Eur J Cardiothorac Surg ; 31(4): 750-2, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17251033

ABSTRACT

Cardiac tumors are detected rarely in childhood. These are most frequently found in infancy, and most are rhabdomyomas. We describe a unique occurrence of a rarely described intracardiac tumor in an asymptomatic 7-year-old child.


Subject(s)
Heart Neoplasms/surgery , Neoplasms, Muscle Tissue/surgery , Child , Echocardiography , Female , Heart Neoplasms/diagnostic imaging , Humans , Neoplasms, Muscle Tissue/diagnostic imaging , Treatment Outcome
19.
Pediatr Nephrol ; 21(5): 711-8, 2006 May.
Article in English | MEDLINE | ID: mdl-16518627

ABSTRACT

We report a Caucasian boy of Italian descent with congenital nephrotic syndrome of the Finnish type (NPHS1, CNF, MIM 256300) who developed recurrence of proteinuria and hypoalbuminemia on the seventh post-operative day following living related renal transplantation from his paternal aunt. The allograft biopsy was normal except for effacement of podocyte foot processes on electron microscopy. He was treated by the substitution of mycophenolate mofetil with cyclophosphamide for 12 weeks, in addition to cyclosporine, prednisone and daclizumab. His proteinuria resolved quickly following the initiation of cyclophosphamide treatment, and he remains in remission 4 years after receiving his transplant. His native and allograft kidneys were evaluated for nephrin expression by immunohistochemistry, DNA analysis for the NPHS1 mutation, serum for the presence of auto-antibodies to nephrin by both enzyme-linked immunosorbent assay (ELISA) and fetal glomeruli immunofluorescence assay, and serum for glomerular permeability to albumin (Palb) activity using a functional in vitro assay for Palb. Nephrin expression was completely absent in the native kidney, while it was decreased in the allograft compared with normal. DNA analysis of the NPHS1 gene revealed mutations 3248G>T and 3250delG in exon 24, causing G1083V and 1084Vfs, respectively, inherited from his father, and 3478C>T in exon 27, that leads to R1160X, inherited from his mother. Serum was negative for auto-antibodies to nephrin. Interestingly, the Palb activity was increased at the time of recurrence of proteinuria following transplantation (Palb 0.73+/-0.10) and remained elevated when retested more than 3 years later (Palb 0.54+/-0.09). This is the first report of increased Palb activity in recurrence of proteinuria following transplantation in NPHS1. We speculate the role of increased Palb activity in the recurrence of proteinuria following transplantation in NPHS1.


Subject(s)
Immunosuppressive Agents/therapeutic use , Kidney Transplantation/adverse effects , Living Donors , Nephrotic Syndrome/congenital , Nephrotic Syndrome/physiopathology , Proteinuria/physiopathology , Albumins/metabolism , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Autoantibodies/immunology , Capillary Permeability/physiology , Cyclophosphamide/therapeutic use , Cyclosporine/therapeutic use , Daclizumab , Humans , Hypoalbuminemia/etiology , Immunoglobulin G/therapeutic use , Infant, Newborn , Kidney Glomerulus/physiopathology , Male , Membrane Proteins/biosynthesis , Membrane Proteins/genetics , Membrane Proteins/immunology , Mutation , Mycophenolic Acid/analogs & derivatives , Mycophenolic Acid/therapeutic use , Nephrectomy , Nephrotic Syndrome/genetics , Nephrotic Syndrome/therapy , Peritoneal Dialysis , Prednisone/therapeutic use , Proteinuria/drug therapy , Proteinuria/etiology , Recurrence
20.
Dig Dis Sci ; 50(6): 1012-8, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15986846

ABSTRACT

To determine if chronic gastritis (CG) is associated with gastric dysrhythmia or delayed solid emptying in children with dyspepsia, 22 patients (7-15 years of age) with dyspepsia and normal gross endoscopies were studied. Antral biopsies were evaluated for chronic gastritis, and immunohistology was performed to determine densities of CD3+, CD20+, CD25+, and tryptase-positive cells. Electrogastrography (EGG) and gastric scintiscan evaluation were performed within 2-7 days of endoscopy. CG and increased immune cell densities were not associated with altered gastric emptying. Mean CD3+ cell counts were positively correlated with the percentage normal slow waves, and patients with a normal EGG had increased CD3+ cell density. In children with dyspepsia, chronic antral inflammation in the setting of a normal gross endoscopy is not associated with EGG abnormalities or delayed solid emptying. Chronic gastritis and gastric dysrhythmia may simply be two separate and distinct mechanisms resulting in the clinical entity of dyspepsia.


Subject(s)
Dyspepsia/etiology , Gastritis/complications , Gastroparesis/complications , Adolescent , Child , Chronic Disease , Dyspepsia/immunology , Electrodiagnosis , Female , Gastric Emptying/physiology , Gastric Mucosa/immunology , Gastritis/diagnosis , Gastritis/immunology , Gastroparesis/diagnosis , Gastroparesis/immunology , Humans , Male , Mast Cells/immunology , Stomach/immunology , Stomach/innervation
SELECTION OF CITATIONS
SEARCH DETAIL
...