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1.
Neotrop Entomol ; 47(3): 369-378, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29322381

RESUMEN

A study was conducted on the Neotropical scale insect genus Coccidella Hambleton (Hemiptera: Coccomorpha: Rhizoecidae) based on soil sample material deposited at the Hungarian Natural History Museum. Descriptions of the adult females of two new Coccidella species, i.e., Coccidella hexapora Kaydan & Konczné Benedicty, sp. n. and Coccidella kozari Kaydan & Szita, sp. n., are provided, plus a redescription and illustration of adult female of Coccidella kissbalazsi Konczné Benedicty & Kozár. An identification key and new additional locality records for the currently known Coccidella species are provided and the affinities of the new species are discussed.


Asunto(s)
Hemípteros/clasificación , Animales , Bolivia , Brasil , Chile , Colombia , Ecuador , Femenino , Hemípteros/anatomía & histología , Perú
2.
AJNR Am J Neuroradiol ; 35(6 Suppl): S64-80, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24557702

RESUMEN

Pediatric bipolar disorder is a severe mental illness whose pathophysiology is poorly understood and for which there is an urgent need for improved diagnosis and treatment. MR spectroscopy is a neuroimaging method capable of in vivo measurement of neurochemicals relevant to bipolar disorder neurobiology. MR spectroscopy studies of adult bipolar disorder provide consistent evidence for alterations in the glutamate system and mitochondrial function. In bipolar disorder, these 2 phenomena may be linked because 85% of glucose in the brain is consumed by glutamatergic neurotransmission and the conversion of glutamate to glutamine. The purpose of this article is to review the MR spectroscopic imaging literature in pediatric bipolar disorder, at-risk samples, and severe mood dysregulation, with a focus on the published findings that are relevant to glutamatergic and mitochondrial functioning. Potential directions for future MR spectroscopy studies of the glutamate system and mitochondrial dysfunction in pediatric bipolar disorder are discussed.


Asunto(s)
Trastorno Bipolar/diagnóstico , Trastorno Bipolar/metabolismo , Encéfalo/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Pediatría , Niño , Humanos
3.
Nanotechnology ; 19(43): 435601, 2008 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-21832697

RESUMEN

Vertically aligned double- and single-walled carbon nanotubes (DWNTs and SWNTs) were synthesized on a substrate at 590 °C by hot-filament chemical vapor deposition. An optimized combination of iron and aluminum layers as the catalyst resulted in iron particles ranging from 1-5 nm floating in an aluminum matrix after annealing. Selective synthesis of DWNTs and SWNTs from such particles was achieved by adjusting the dilution ratio of acetylene that was used as the source gas. The yield of DWNTs among all CNTs was as high as 81%, while that of SWNTs was almost 100%. The diameter distribution of DWNTs was narrow, with a standard deviation of about 12%.

4.
Kidney Int ; 71(5): 379-81, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17315006

RESUMEN

Incompleteness of O-glycosylation in the IgA1 hinge has been implicated as a central mechanism in the development of IgA nephropathy. Although underglycosylation was reported to be an acquired abnormality, genes for enzymes of O-glycosylation, such as C1GALT1, may be responsible for susceptibility to IgA nephropathy.


Asunto(s)
Galactosiltransferasas/genética , Predisposición Genética a la Enfermedad , Glomerulonefritis por IGA/genética , Inmunoglobulina A/metabolismo , Glomerulonefritis por IGA/enzimología , Glicosilación , Humanos
5.
Kidney Int ; 69(9): 1626-32, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16672924

RESUMEN

Although uremia is well known as the most common cause of pruritus, the mechanisms of pruritus in chronic hemodialysis patients remain unclear. The purpose was to characterize uremic pruritus in more detail and to investigate whether severe pruritus is a marker for poor prognosis. A total of 1773 adult hemodialysis patients were studied. A questionnaire was given to each patient to assess the intensity and frequency, as well as pruritus-related sleep disturbance. We analyzed the relationship between clinical and laboratory data and the severity of pruritus in hemodialysis patients and followed them for 24 months prospectively. In total, 453 patients had severe pruritus with a visual analogue scale (VAS) score more than or equal to 7.0. Among them, more than 70% complained of sleep disturbance, whereas the majority of patients with a VAS score of less than 7.0 had no sleep disturbance. Male gender, high levels of blood urea nitrogen, beta2-microglobulin (beta2MG), hypercalcemia, and hyperphosphatemia were identified as independent risk factors for the development of severe pruritus, whereas a low level of calcium and intact-parathyroid hormone were associated with reduced risk. During the follow-up, 171 (9.64%) patients died. The prognosis of patients with severe pruritus was significantly worse than the others. Moreover, severe pruritus was independently associated with death even after adjusting for other clinical factors including diabetes mellitus, age, beta2MG, and albumin. Severe uremic pruritus caused by multiple factors, not only affects the quality of life but may also be associated with poor outcome in chronic hemodialysis patients.


Asunto(s)
Prurito/epidemiología , Prurito/etiología , Diálisis Renal , Uremia/complicaciones , Uremia/terapia , Anciano , Biomarcadores/sangre , Nitrógeno de la Urea Sanguínea , Femenino , Humanos , Hipercalcemia/sangre , Masculino , Persona de Mediana Edad , Fosfatos/sangre , Pronóstico , Factores de Riesgo , Trastornos del Sueño-Vigilia/diagnóstico , Resultado del Tratamiento , Microglobulina beta-2/sangre
6.
Tissue Antigens ; 64(1): 35-42, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15191521

RESUMEN

Transforming growth factor (TGF)-beta1, a multifunctional cytokine, which regulates proliferation and differentiation of a variety of cell types, has the central role in the development and progression of renal injury in both animal models and human. Although it has been suggested that genetic variations in the TGF-beta1 gene are associated with the activity of the gene product, their clinical significance in glomerular disease is unknown. We investigated whether the polymorphisms of C-509T and T869C in TGF-beta1 account for interindividual variation in manifestations of IgA nephropathy (IgAN) using 626 Japanese subjects including 329 patients with histologically proven IgAN and 297 healthy controls with normal urinalysis. The frequencies of genotypes, alleles, and major haplotypes were similar between the patients and controls. The C-509T and T869C polymorphisms were in tight linkage disequilibrium, and the major haplotypes were C-C and T-T, which accounted for more than 95% of the total. In patients with -509CC and in those with the 869CC, urinary protein excretion was higher than in those with other genotypes, whereas no difference in other clinical manifestations was noted. Moreover, patients with -509CC and those with 869CC genotypes presented with a significant higher score of mesangial cell proliferation than in those with other genotypes. These results suggest that TGF-beta1 gene polymorphisms are specifically associated with heavy proteinuria and mesangial cell proliferation in Japanese patients with IgAN, although they do not confer susceptibility to this disease.


Asunto(s)
Glomerulonefritis por IGA/genética , Glomerulonefritis por IGA/inmunología , Factor de Crecimiento Transformador beta/genética , Adulto , Anciano , Secuencia de Bases , Estudios de Casos y Controles , ADN/genética , Femenino , Frecuencia de los Genes , Glomerulonefritis por IGA/patología , Haplotipos , Humanos , Japón , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Factor de Crecimiento Transformador beta1
9.
Kyobu Geka ; 56(5): 427-9, 2003 May.
Artículo en Japonés | MEDLINE | ID: mdl-12739370

RESUMEN

A case of a patient with a intrathoracic chronic expanding hematoma presenting as a neoplasm is reported. A chronic encapsulated intrathoracic hematoma is rare condition and is clinically included in a category of chronic hemorrhagic empyemas as a type of chronic empyemas in Japan. The clinical picture of our case suggested a slowly growing tumor. Though needle biopsy was performed, only blood was aspirated. Intraoperative findings revealed a intrathoracic hematoma with a tough capsule. It adhered to the chest wall hardly. Histopathological investigations revealed that the capsule consisted of a collagenous outer layer and a newly vascularized inner layer with fibrosis. Hemosiderin deposits suggested recurrent bleeding from fragile vessels. The mechanisms of hematoma formation and its expanding nature are discussed. The hematoma appeared to have been enlarged by repeated exudation or bleeding from capillaries inside the capsule.


Asunto(s)
Hematoma/cirugía , Enfermedades Torácicas/cirugía , Enfermedad Crónica , Humanos , Masculino , Persona de Mediana Edad
10.
Intern Med ; 40(9): 867-72, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11579946

RESUMEN

OBJECTIVE: In order to explore the possibility that genetic predisposition to dysfunction of mucosal immunity and the IgA processing pathway plays a role in the pathogenesis of mesangial IgA1 deposition in IgAN, we examined the possible association of the gene polymorphism of pIgR in the patients with and without IgAN. SUBJECTS AND METHODS: Genomic DNA of peripheral blood cells was isolated from 372 individuals including 172 histologically confirmed IgAN patients. Segments of the pIgR gene were PCR amplified and restriction fragment length polymorphism was determined as A1 and A2 with and without Pvu II site, respectively. RESULTS: The pIgR genotype distribution was significantly different between the patients with IgAN and those without IgAN. Allele frequency of A2 was higher in IgAN than in other renal diseases (A1 and A2; 0.516 and 0.484 in IgAN, 0.641 and 0.359 in others, chi2 = 9.84, P = 0.0017, Odds ratio = 1.71). Moreover, the subjects with A2A2 genotype were associated with a relatively low level of serum IgA only in the patients with IgAN but not in other renal diseases. The difference of allele frequencies was more remarkable in the patients with a serum IgA level of less than 300 mg/dl (A1 and A2; 0.439 and 0.561 in IgAN, 0.702 and 0.298 in others, chi2 = 12.44, P = 0.0004, Odds ratio = 3.01). CONCLUSION: This is the first demonstration of the pIgR gene polymorphisms in IgAN which are associated with its clinical phenotype. Gene polymorphisms of pIgR may be candidate genetic markers of susceptibility to IgAN.


Asunto(s)
Glomerulonefritis por IGA/genética , Polimorfismo de Nucleótido Simple , Receptores Fc/genética , Receptores de Inmunoglobulina Polimérica/genética , Alanina/genética , Alelos , Marcadores Genéticos , Genotipo , Glicina/genética , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN , Treonina/genética
11.
J Synchrotron Radiat ; 8(Pt 2): 505-7, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11512831

RESUMEN

We report here the temperature-dependent unoccupied molecular orbitals (MO's) of C60 molecules adsorbed on a Si(001)-(2 x 1) surface measured using near edge x-ray absorption fine structure (NEXAFS). At 300 K, the NEXAFS spectrum reveals that the interaction between a 1.0 monolayer (ML) C60 film and a Si(001) surface is mainly the van der Waals force. After annealing the samples at 500 K, we observe an increment in the full-width at half-maximum of unoccupied MO's, which indicates the change of the interaction. Moreover, the lowest unoccupied molecular orbital (LUMO) shifts to the higher photon energy side and the intensity of the LUMO+1 relative to that of the LUMO+3 decreases in the NEXAFS spectrum. These results suggest that the strong interaction induced at 500 K has a covalent character, to which the LUMO+1 contributes.

12.
Kidney Int ; 59(5): 1911-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11318963

RESUMEN

BACKGROUND: Hyperlipoproteinemia is occasionally associated with severe glomerular injury caused by abnormal accumulation of lipid in glomeruli, which occurs in conditions such as lipoprotein glomerulopathy (LPG). This study investigates the cases of two siblings with homozygous apolipoprotein (apo) E2 who show unique histologic features, massive proteinuria, and dysbetalipoproteinemia. METHODS: Histologic studies were performed using renal biopsy specimens. Plasma lipoproteins were extensively characterized. The exons of the apo E genes were sequenced to avoid missing any mutations. RESULTS: Histologically, the siblings' condition resembled LPG by light microscopy studies. Electron microscopy studies revealed large lipoid deposits in the paramesangium, subendothelium, and subepithelium of the glomeruli, which were different from LPG in terms of not forming the layered structure resembling a fingerprint even in large lipoprotein thrombi, and mesangial foam cells. Immunohistochemically, the lipoid deposits contained apo E and apo B. These patients did not have either diabetic nephropathy or other known forms of glomerulonephritis. The sequence of exons of the apo E genes revealed homozygosity for apo E2 in both cases. CONCLUSION: The extensive lipoprotein deposition in glomeruli, which resembles LPG, can also occur in apo E2 homozygous individuals, but in a distinct fashion. Because the two cases were siblings, they may have other shared alleles, in addition to the apo E2 allele, that negatively affect processing of lipoproteins and lead to abnormal accumulation of lipoprotein deposits in glomeruli.


Asunto(s)
Apolipoproteínas E/genética , Hiperlipoproteinemias/genética , Hiperlipoproteinemias/metabolismo , Enfermedades Renales/genética , Enfermedades Renales/metabolismo , Glomérulos Renales/metabolismo , Lipoproteínas/genética , Lipoproteínas/metabolismo , Secuencia de Aminoácidos , Apolipoproteína E2 , Secuencia de Bases , ADN/genética , Análisis Mutacional de ADN , Cartilla de ADN/genética , Femenino , Genotipo , Homocigoto , Humanos , Hiperlipoproteinemias/patología , Enfermedades Renales/patología , Glomérulos Renales/patología , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Fenotipo
13.
Hypertens Res ; 24(2): 111-7, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11325069

RESUMEN

This study investigates the circadian blood pressure variation of non-diabetic chronic hemodialysis (HD) patients on both HD and non-HD days as well as the factors affecting diurnal BP variation. Forty-nine HD patients aged 61.8 +/- 12.9 years who were on daytime HD for 97 +/- 68 months were studied. No significant difference was found in every daytime and nighttime BP between the first (HD) and the second (non-HD) day. However, the ratio nighttime/daytime BP was significantly higher on the second day. Each BP diurnal variability pattern was classified as either Dipper (D: the ratio nighttime/daytime mean BP 0.8-0.9), non-dipper (0.9 < ND < 1.0), or inverted dipper (ID > 1.0). More than 75% of the cases were classified as ND (26 cases) or ID (11 cases). The ultrafiltration rate in D was significantly less than that in ND and ID. The difference of plasma renin activity between pre- and post-HD (dRen) was significantly higher in ID than in D and ND. The amount of dialysis (Kt/V) was found to be significantly correlated with nighttime BP fall. Ultrafiltration, dRen and Kt/V were independent factors for the abnormal BP diurnal variability. In conclusion, the decreased nocturnal BP fall seen in non-diabetic HD patients is associated with increased extracellular fluid even in the patients without overt overhydration, whereas relatively insufficient amount of dialysis (low Kt/V) may be another possible cause. The increased dRen observed only in ID patients may reflect occult cardiovascular damage or functional disturbances in aortic and carotid baroreflexes caused by arterial structural changes.


Asunto(s)
Presión Sanguínea , Ritmo Circadiano , Hipertensión/diagnóstico , Fallo Renal Crónico/diagnóstico , Adulto , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Femenino , Humanos , Hipertensión/epidemiología , Fallo Renal Crónico/epidemiología , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Diálisis Renal , Renina/sangre , Factores de Riesgo
14.
Jpn J Thorac Cardiovasc Surg ; 48(8): 540-1, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11002590

RESUMEN

Pulmonary aspergillosis and lung cancer rarely occur simultaneously. We report a 66-year-old man with a round shadow in the thin-wall cavity of the right upper lobe. Radiological findings and transbronchial biopsy revealed squamous cell carcinoma complicated by aspergilloma at the site. Right upper lobectomy suggested that early lung cancer arose from preexisting lung scars containing an aspergilloma.


Asunto(s)
Aspergilosis/complicaciones , Carcinoma de Células Escamosas/complicaciones , Enfermedades Pulmonares Fúngicas/complicaciones , Neoplasias Pulmonares/complicaciones , Anciano , Carcinoma de Células Escamosas/cirugía , Humanos , Neoplasias Pulmonares/cirugía , Masculino
15.
JAMA ; 284(9): 1111-3, 2000 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-10974690

RESUMEN

CONTEXT: Although concerns continue to be raised about the diversity of the US physician workforce, there has never been a nationwide survey of both the sex and underrepresented minority (URM) composition of medical school admission committees. OBJECTIVE: To document US medical school admission committee membership in several demographic domains, including sex and URM (African American, Mexican American, mainland Puerto Rican, Native American, Native Hawaiian, and Native Alaskan) status. DESIGN: Mailed survey. SETTING AND PARTICIPANTS: Deans or directors of admission at 85 US medical schools that were members of the Association of American Medical Colleges (response rate, 70%). MAIN OUTCOME MEASURES: Prevalence of 1999-2000 school-year committee members in demographic categories, such as sex, URM status, physician or medical student status; compensation status. RESULTS: The overall ratio of men to women on admission committees was 1.77 to 1. On average, 16% of committee members were from URM groups. Physicians with URM status comprised 8% of committee membership; 51% of committees had 1 or 0 URM physicians. Seventy-four percent of committees had at least 1 medical student; medical students comprised 15% of total membership. Ninety-one percent of committees operated on a volunteer basis. CONCLUSION: Although representation of women and persons with URM status on medical school admission committees has improved since 1972, URM membership, in particular, remains low. JAMA. 2000;284:1111-1113


Asunto(s)
Demografía , Facultades de Medicina/organización & administración , Recolección de Datos , Femenino , Humanos , Masculino , Grupos Minoritarios/estadística & datos numéricos , Criterios de Admisión Escolar , Facultades de Medicina/estadística & datos numéricos , Distribución por Sexo , Encuestas y Cuestionarios , Estados Unidos
17.
RNA ; 6(2): 220-32, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10688361

RESUMEN

The many interactions of tRNA with the ribosome are fundamental to protein synthesis. During the peptidyl transferase reaction, the acceptor ends of the aminoacyl and peptidyl tRNAs must be in close proximity to allow peptide bond formation, and their respective anticodons must base pair simultaneously with adjacent trinucleotide codons on the mRNA. The two tRNAs in this state can be arranged in two nonequivalent general configurations called the R and S orientations, many versions of which have been proposed for the geometry of tRNAs in the ribosome. Here, we report the combined use of computational analysis and tethered hydroxyl-radical probing to constrain their arrangement. We used Fe(II) tethered to the 5' end of anticodon stem-loop analogs (ASLs) of tRNA and to the 5' end of deacylated tRNA(Phe) to generate hydroxyl radicals that probe proximal positions in the backbone of adjacent tRNAs in the 70S ribosome. We inferred probe-target distances from the resulting RNA strand cleavage intensities and used these to calculate the mutual arrangement of A-site and P-site tRNAs in the ribosome, using three different structure estimation algorithms. The two tRNAs are constrained to the S configuration with an angle of about 45 degrees between the respective planes of the molecules. The terminal phosphates of 3'CCA are separated by 23 A when using the tRNA crystal conformations, and the anticodon arms of the two tRNAs are sufficiently close to interact with adjacent codons in mRNA.


Asunto(s)
ARN de Transferencia/química , ARN de Transferencia/metabolismo , Ribosomas/metabolismo , Anticodón/genética , Bacteriófago T4/genética , Secuencia de Bases , Sitios de Unión/genética , Codón/genética , Proteínas de Unión al ADN/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Radical Hidroxilo/química , Hierro/química , Modelos Moleculares , Técnicas de Sonda Molecular , Conformación de Ácido Nucleico , ARN de Transferencia/genética , Proteínas Virales/genética
18.
Am J Physiol ; 276(3): C621-7, 1999 03.
Artículo en Inglés | MEDLINE | ID: mdl-10069989

RESUMEN

A family of water-selective channels, aquaporins (AQP), has been demonstrated in various organs and tissues. However, the localization and expression of the AQP family members in the gastrointestinal tract have not been entirely elucidated. This study aimed to demonstrate the expression and distribution of several types of the AQP family and to speculate on their role in water transport in the rat gastrointestinal tract. By RNase protection assay, expression of AQP1-5 and AQP8 was examined in various portions through the gastrointestinal tract. AQP1 and AQP3 mRNAs were diffusely expressed from esophagus to colon, and their expression was relatively intense in the small intestine and colon. In contrast, AQP4 mRNA was selectively expressed in the stomach and small intestine and AQP8 mRNA in the jejunum and colon. Immunohistochemistry and in situ hybridization demonstrated cellular localization of these AQP in these portions. AQP1 was localized on endothelial cells of lymphatic vessels in the submucosa and lamina propria throughout the gastrointestinal tract. AQP3 was detected on the circumferential plasma membranes of stratified squamous epithelial cells in the esophagus and basolateral membranes of cardiac gland epithelia in the lower stomach and of surface columnar epithelia in the colon. However, AQP3 was not apparently detected in the small intestine. AQP4 was present on the basolateral membrane of the parietal cells in the lower stomach and selectively in the basolateral membranes of deep intestinal gland cells in the small intestine. AQP8 mRNA expression was demonstrated in the absorptive columnar epithelial cells of the jejunum and colon by in situ hybridization. These findings may indicate that water crosses the epithelial layer through these water channels, suggesting a possible role of the transcellular route for water intake or outlet in the gastrointestinal tract.


Asunto(s)
Acuaporinas/metabolismo , Sistema Digestivo/metabolismo , Canales Iónicos , Animales , Acuaporina 4 , Acuaporinas/genética , Inmunohistoquímica , Hibridación in Situ , Hibridación de Ácido Nucleico , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas WKY , Ribonucleasas , Distribución Tisular
19.
Am J Physiol ; 275(4): C1151-7, 1998 10.
Artículo en Inglés | MEDLINE | ID: mdl-9755069

RESUMEN

Aquaporin (AQP) 5 gene was recently isolated from salivary gland and identified as a member of the AQP family. The mRNA expression and localization have been examined in several organs. The present study was focused on elucidation of AQP5 expression and localization in the eye, salivary gland, and lung in rat. RNase protection assay confirmed intense expression of AQP5 mRNA in these organs but negligible expression in other organs. To examine the mRNA expression sites in the eye, several portions were microdissected for total RNA isolation. AQP5 mRNA was enriched in cornea but not in other portions (retina, lens, iris/ciliary body, conjunctiva, or sclera). AQP5 was selectively localized on the surface of corneal epithelium in the eye by immunohistochemistry and immunoelectron microscopy using an affinity-purified anti-AQP5 antibody. AQP5 was also localized on apical membranes of acinar cells in the lacrimal gland and on the microvilli protruding into intracellular secretory canaliculi of the serous salivary gland. In the lung, apical membranes of type I pulmonary epithelial cells were also immunostained with the antibody. These findings suggest a role of AQP5 in water transport to prevent dehydration or to secrete watery products in these tissues.


Asunto(s)
Acuaporinas/biosíntesis , Acuaporinas/genética , Córnea/metabolismo , Células Epiteliales/metabolismo , Epitelio Corneal/metabolismo , Pulmón/metabolismo , Proteínas de la Membrana , Glándulas Salivales/metabolismo , Transcripción Genética , Secuencia de Aminoácidos , Animales , Acuaporina 5 , Acuaporinas/análisis , Western Blotting , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Clonación Molecular , Cartilla de ADN , Epitelio Corneal/citología , Epitelio Corneal/ultraestructura , Microscopía Inmunoelectrónica , Microvellosidades/metabolismo , Microvellosidades/ultraestructura , Datos de Secuencia Molecular , Especificidad de Órganos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , Ratas , Ratas Endogámicas WKY
20.
J Am Soc Nephrol ; 9(7): 1234-41, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9644633

RESUMEN

The earliest commitment to the formation of glomeruli is recognizable in S-shaped bodies. Although cell-cell adhesion seems likely to play a crucial role in this process, how glomerular epithelial cells segregate from the other parts of the nephron is unknown. In this study, immunofluorescence microscopy and monoclonal antibodies specific for mouse R-, E-, P- and N-cadherins were used to examine which of these adhesion molecules are involved in glomerulogenesis of the mouse kidney. Weak R-cadherin staining was first found in the vesicle stage, becoming restricted to glomerular visceral epithelial cells (VEC) during the S-shaped body stage. The intensity of this staining became stronger in the capillary loop stage, whereas parietal epithelial cells (PEC) and tubular cells did not stain. In the maturing stage, VEC gradually lost their staining for R-cadherin. E-cadherin was detected in ureteric buds and the upper limb of S-shaped bodies. From the capillary loop to the maturing stage, anti-E-cadherin stained epithelial cells in all tubule segments, but no label was seen in VEC or PEC. P-cadherin was also stained in the ureteric buds and in the upper limb of S-shaped bodies. N-Cadherin was weakly stained in cells at the vesicle stage, but thereafter staining of N-cadherin was not detected at any stage of glomerular formation. Immunoelectron microscopy of differentiating VEC was performed using antibodies specific to alpha-catenin, which is associated with cadherin. Subsequently, immunogold particles identifying alpha-catenin were localized on junctions between primary processes of VEC. These findings indicate that R-cadherin is uniquely expressed in differentiating VEC, suggesting an important role in the early stages of glomerulogenesis.


Asunto(s)
Cadherinas/análisis , Glomérulos Renales/crecimiento & desarrollo , Glomérulos Renales/ultraestructura , Animales , Animales Recién Nacidos , Membrana Basal/química , Membrana Basal/ultraestructura , Western Blotting , Cadherinas/fisiología , Membrana Celular/ultraestructura , Citoplasma/ultraestructura , Desarrollo Embrionario y Fetal , Técnica del Anticuerpo Fluorescente Indirecta , Uniones Intercelulares/ultraestructura , Glomérulos Renales/química , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica , Técnicas de Cultivo de Órganos , Sensibilidad y Especificidad
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