The Role of MMP-9 in Regulating Degradation of the Splenic Microvascular Basement Membrane Induced by High Altitude Hypoxia / Rol de la MMP-9 en la Regulación de la Degradación de la Membrana Basal Microvascular Esplénica Inducida por Hipoxia de Altura

SUMMARY: To investigate changes of MMP-9 in the rat spleen and hypoxia-induced microvascular basement membrane under high altitude hypoxia. Thirty male specific pathogen-free Sprague Dawley rats were randomly divided into control and hypoxia groups, with 15 rats in each group. The rats in the control group were placed in Dingxi City, Gansu Province (2080 m above sea level) for 30 days. Rats in the hypoxia group were raised in a hypoxic environment in Maduo County, Qinghai Province (4300 m above sea level), for 30 days to establish a hypoxic rat model. Routine blood tests, MMP-9 mRNA, MMP-9 protein, and the spleen microvascular basement membrane were detected. (1) Compared with the control group, the red blood cell count, hemoglobin, and hematocrit levels of the rats in the hypoxia group were all increased; thus, a hypoxia model was successfully established. (2) Compared with the control group, the expression of MMP-9 mRNA and protein was significantly higher in the spleen of rats in the hypoxic group, and the difference was statistically significant (P <0.05). (3) Compared with the control group, the blood vessel basement membrane in the spleen of the hypoxia group was degraded. Under natural low air pressure and high altitude conditions, the expression of MMP-9 in rat spleen tissue increases and participates in the degradation of the microvascular basement membrane.

El objetivo de este trabajo fue investigar los cambios de la MMP-9 en el bazo de la rata y la membrana basal microvascular inducida bajo hipoxia a gran altura. Treinta ratas macho Sprague Dawley, libres de patógenos específicos, se dividieron aleatoriamente en dos grupos de 15 ratas cada uno, un grupo control y un grupo hipoxia. Durante 30 días las ratas del grupo control estuvieron en la ciudad de Dingxi, provincia de Gansu (2080 m sobre el nivel del mar). Las ratas del grupo de hipoxia se criaron en un entorno hipóxico en el condado de Maduo, provincia de Qinghai (4300 m sobre el nivel del mar), durante 30 días para establecer un modelo de rata hipóxica. Se realizaron análisis de sangre de rutina, ARNm de MMP-9, proteína MMP-9 y de la membrana basal microvascular del bazo. En comparación con el grupo control, el recuento de glóbulos rojos, la hemoglobina y los niveles de hematocrito de las ratas del grupo de hipoxia aumentaron; por lo tanto, se estableció con éxito un modelo de hipoxia. En comparación con el grupo control, la expresión de ARNm y proteína de MMP-9 fue significativamente mayor en el bazo de las ratas del grupo hipóxico, siendo la diferencia estadísticamente significativa (P <0,05). En comparación con el grupo control, la membrana basal de los vasos sanguíneos estaba degradada en el bazo del grupo hipoxia. En condiciones naturales de baja presión atmosférica y gran altitud, la expresión de MMP-9 en el tejido del bazo de la rata aumenta y participa en la degradación de la membrana basal microvascular.

COVID-19, glomerulonefritis ANCA y anti-membrana basal glomerular. Caso clínico / Association of COVID-19 and glomerulonephritis with ANCA and anti-glomerular basement membrane antibodies. Report of one case

Renal involvement in COVID-19 infection is varied and worsens its outcome and prognosis. However, the association of COVID-19 infection with glomerulonephritis is exceptional. We report a 46-year-old woman with COVID-19 who had an acute kidney injury and ANCA associated glomerulonephritis two weeks after the onset of the disease. The kidney biopsy showed a crescentic glomerulo-nephritis and the presence of anti-glomerular basement membrane antibodies (GBM-Abs). She was treated with steroids and oral cyclophosphamide with good response without requiring plasmapheresis. Plasma anti GBM-Abs were negative. This case suggests that the presence of anti-GBM-Abs in the kidney, was temporally related to COVID-19 pulmonary damage. The absence of plasma antibodies is probably due to transient production and glomerular adsorption, but with unknown pathogenic role.

Bullous systemic lupus erythematosus in a 10-year-old child

Abstract: Bullous systemic lupus erythematosus (BSLE) is a rare autoimmune subepidermal blistering disease, with few cases described in childhood. It has different clinical-pathological features. We report a case of BSLE in a 10-year-old child with systemic lupus erythematosus, treated with prednisone and hydroxychloroquine. There was complete remission with dapsone, with no recurrence of skin lesions throughout one year of follow-up. We highlight the rarity and early age of occurrence.

Linear IgA and IgG bullous dermatosis

Abstract Childhood linear immunoglobulin A dermatosis is a rare autoimmune vesiculobullous disease. It results in linear deposition of autoantibodies (immunoglobulin A) against antigens in the basal membrane zone, leading to subepidermal cleavage. Additional depositions of immunoglobulin G and complement-3 might occur. It is still debated whether concomitant findings of immunoglobulins A and G should be considered a subtype of this dermatosis or a new entity. Further studies are needed to recognize this clinical variant.

Argon Green Laser for Valsalva Retinopathy Treatment and Long-term Follow-up of the Internal Limiting Membrane Changes in Optical Coherence Tomography

No abstract available.

Imunoglobulina intravenosa para tratamento de epidermólise bolhosa adquirida grave refratária a terapia imunossupressora convencional / Intravenous immunoglobulin for treatment of severe acquired bullous epidermolysis refractory to conventional immunosuppressive therapy

A epidermólise bolhosa adquirida é doença bolhosa subepidérmica crônica e rara. Geralmente, inicia-se na fase adulta, sendo a etiologia desconhecida, embora vinculada à presença de anticorpos contra o colágeno tipo VII. Há formação de bolhas, espontaneamente ou após trauma, podendo causar complicações graves. O tratamento é desapontador e difícil. Além da terapia convencional com corticoides sistêmicos, recentemente, novas modalidades terapêuticas promissoras estão sendo utilizadas, dentre elas, a imunoglobulina intravenosa. Destaca-se, neste relato, o difícil manejo clínico desta doença, e a melhora importante com a imunoglobulina intravenosa.

Acquired bullous epidermolysis is a chronic and rare bullous subepidermal disease. It usually begins in adulthood and its etiology is unknown although it is associated with antibodies against type VII collagen. There are spontaneous and trauma induced formation of blisters that may cause serious complications. Treatment is disappointing and difficult. Apart from conventional therapy with systemic corticosteroid, new therapeutic modalities such as intravenous immunoglobulin are currently being used. This report highlights the extremely difficult clinical management of this rare disease and the important improvement provided by intravenous immunoglobulin.

Alport syndrome: significance of gingival biopsy in the initial diagnosis and periodontal evaluation after renal transplantation

Alport Syndrome (AS) is an important hereditary disorder affecting the glomerular basement membrane. Diagnosis of AS is based on the presence of hematuric nephropathy, renal failure, hearing loss, ocular abnormalities and changes in the glomerular basement membrane of the lamina densa. The aims of this case report were to show the changes in the gingival tissues in a patient with AS under therapy with cyclosporin-A after renal transplantation and to discuss the possible role of type IV collagen in gingival basal lamina as an alternative approach for the diagnosis of AS. A 20-year-old male patient with AS underwent periodontal therapy including a series of gingivectomy surgeries. Gingival samples obtained during the second surgery were examined histopathologically and by transmission electron microscopy for further pathological examination. Gingivectomy procedures have been performed every 6 months over the last 4 years. The excessive and fibrous gingival enlargements resulted in migration of the anterior teeth, but no alveolar bone loss occurred. This is the first report to demonstrate the possible changes in the gingival tissues caused by AS. It is suggested that gingival biopsy can be an initial diagnostic tool instead of renal or skin biopsies. Proper dental and periodontal care and regular visits to the dentist could provide limited gingival hyperplasia to patients with AS.

Correlation of " in vivo" microcirculation and degeneration of the basal cells of the epithelium in lingual lichen planus.

Background: Oral lichen planus is an inflammatory chronic disease with an autimmune pathogenesis and unknown etiology that affects oral mucosa, with or without the involvement of the skin and other mucous membranes. The principal histological characteristics are the degeneration of the basal cell layer and the abnormal infiltration of inflammatory cells into the subepithelial layer of connective tissue. Objectives: This study is aimed to appraise if lingual lichen planus (LLP) is sustained by alteration of the oral microcirculation and if this abnormal vascularisation increases the degeneration of basal keratinocytes and the disruption of the basement membrane. Materials and Methods: Fifteen patients with a histological diagnosis of LLP with higher degree of degeneration of the basement membrane, fifteen LLP patients with lower degree of basement membrane (BM) degeneration and fifteen healthy patients were included in the study. The microcirculation of the left margin of the lingual mucosa of all the patients and subjects was analysed with the videocapillaroscopy. The following parameters were analyzed on each capillaroscopic image: c0 apillary loop length, loop diameter, and capillary density. The results obtained by videocapillaroscopy software were subjected to statistical analysis using Mann Whitney U-test (P < 0.001). Statistical analysis was performed using PAST software, v. 1.53. Results: Capillary density, loop length, and total diameter showed statistically significant differences between LLP patients with histologically lower degree of BM degeneration and healthy subjects and a meaningful significant difference between LLP patients with higher degree of BM degeneration. Conclusions: A remarkable increase in capillary density was showed by videocapillaroscopic exam. The increased value of the density could be associated with angiogenesis mechanism and it could be an indicator of the evolutionary condition of LLP. Videocapillaroscopy may be useful for the evaluation of the evolution or regression of the disease.

Aspectos histoquímicos da membrana basal associados a variáveis clínicas em carcinoma epidermóide oral / Histochemical aspects of the basal membrane associated with clinical variables in oral squamous cell carcinoma

Objetivo: Avaliar o comportamento da membrana basal em lesões do carcinoma epidermóide oral, relacionando esse comportamento com a classificação clínica TNM, localização anatômica e sobrevida dos pacientes. Método: O estudo foi baseado em uma revisão retrospectiva incluindo a observação histológica de 20 casos de carcinoma epidermóide oral dos arquivos do Laboratório de Patologia do Hospital Estadual Dr. Luis Antônio em Natal, RN, Brasil. Com a análise dos prontuários médicos, foram obtidos os dados referentes à classificação clínica TNM e localização anatômica. A gradação histológica de malignidade foi realizada na área invasiva do tumor por dois patologistas em secções histológicas de 3 micrometros de espessura coradas pela hematoxilina e eosina (HE), para obtenção dos escores histológicos de malignidade, e pelo ácido periódico de Schiff (PAS) para o estudo da membrana basal. Resultados: O principal padrão de marcação da membrana basal foi contínuo, variando entre fraco, moderado e intenso, em lesões com baixo escore de malignidade e principalmente localizadas no lábio com a maioria dos pacientes livres da doença. Em lesões reincidentes principalmente em língua, com alto escore de malignidade, o padrão mais evidente de marcação da membrana basal foi descontínuo ou ausente. Conclusão: Lesões de língua com membrana basal descontínua ou ausente em pacientes com estadiamento clínico TNM III ou IV estão relacionadas com um prognóstico desfavorável, ao contrário, das lesões em lábio com a membrana basal contínua e estadiamento clínico TNM I ou II.

Objective: To evaluate the behavior of the basal membrane in oral squamous cell carcinoma lesions, relating this behavior to the TNM clinical classification, anatomic location and patient survival rate. Method: The study was based on a retrospective review, including the histological examination of 20 oral squamous cell carcinoma cases from the fi les of the Dr. Luis Antonio State Hospital's Pathology Laboratory in the city of Natal, RN, Brazil. Data referring to TNM clinical classification and anatomic location were obtained from the analysis of medical records. The histological grading of malignancy was made by the analysis of 3-micrometrics - thick histological sections stained with hematoxylin and eosin by two pathologists in order to obtain the histological malignancy scores, and by the periodic acid-Schiff (PAS) for the analysis of the basal membrane. Results: The main labeling pattern of the basal membrane was continuous, varying among weak, moderate and severe in lesions with low malignancy scores and were predominantly located in the lower lip in most healthy patients. For the recurrent lesions, mainly located on the tongue, with high malignancy scores, the most evident basal membrane labeling pattern was discontinuous or absent. Conclusion: Tongue lesions with discontinuous or absent basal membrane in patients in the III or IV TNM clinical stages are related to a poor prognosis, unlike lip lesions with continuous basal membrane and classified as I or II TNM clinical stages.

Identifi cation of novel variants in the COL4A4 gene in Korean patients with thin basement membrane nephropathy.

Background & objectives: The α4 chain of the type 4 collagen family is an important component of the glomerular basement membrane (GBM) in the kidney. It is encoded by the COL4A4 gene, and mutations of this gene are known to be associated with thin basement membrane nephropathy (TBMN). To better understand the contribution of variants in the COL4A4 gene to TBMN, we investigated the sequence of the complete COL4A4 gene in 45 Korean patients with TBMN. Method: Genomic DNA was obtained from the peripheral blood lymphocytes. For the analysis of the COL4A4 gene, all the exons including splicing sites were amplififi ed by PCR and screened by direct sequencing analysis. Results: Eight novel COL4A4 sequence variants were found in these patients. Two of these variants, G199R and G1606E, were possibly pathogenic variants affecting the phenotype. None of these variants were observed in 286 chromosomes from normal Korean control subjects. In addition, 39 polymorphisms including 7 novel SNPs were identifi ed in this study. Interpretation & conclusion: The frequency of COL4A4 mutations in Korean patients with TBMN is low and the other cases may have mutations in other genes like COL4A3. Screening of the COL4A3 gene and fi nding a novel causative gene for TBMN will help clarify the pathogenesis of this disorder and perhaps for distinguishing TBMN from Alport syndrome.

Enfermedad autoinmune: perturbación de la conversación entre la célula blanco (epitelial) y la matriz extracelular / Autoimmune disease: impaired cross-talk between epithelial cell and extracellular matrix

Glándulas salivales de pacientes con síndrome de Sjõgren presentan un aumento en la degradación de componentes de la lámina basal (LB, laminina y colágeno IV) y estroma (colágenos I y III y fibronectina). Estos cambios se correlacionan con un desbalance en la expresión y actividad de metaloproteinasas y sus inhibidores titulares (MMP/TIMP) que desorganiza la LB de acinos y ductos. Esta desorganización es concomitante a una sobreexpresión de lamininas -1 y -5 y a la degradación de nidógenos 1 y -2, que tienen como función establecer puentes de conexión entre laminina y colágeno IV. Cambios post-transcripcionales de la integrina alfa 6 beta 4 están correlacionados con una drástica redistribución de beta 4 en acinos con LB desorganizadas. Estos resultados sugieren que alteraciones en la adhesión célula-matriz y en la formación de contactos célula-célula pueden modificar la señalización de la integrina alfa 6 beta 4 induciendo muerte celular cuando hay una severa interrupción de la célula acinar con la LB.

Increased degradation of basal lamina (BL, laminin and type IV collagen) and stroma (type I and III collagens, and fibronectin) proteins have been observed in salivary glands of patients with Sjõgren’s syndrome. Such changes are associated with imbalanced expression and activity of extracellular matrix metalloproteinases and their tissue inhibitors (MMPs/TIMPs), which contribute to disorganization of the parenchyma basal lamina. Disorganization of the basal lamina is paralleled by an overexpression of laminin-1and -5 and the degradation of nidogens 1 and -2: linker proteins that help maintain the integrity of type IV collagen and laminin networks.Additionally, post-transcriptional changes in alpha 6 beta 4 integrin are associated with a dramatic redistribution of beta 4 in acini, particularly where perturbations in BL organization were apparent. These findings are taken to suggest that changes in acinar cell-matrix adhesion and cell-cell contact formation may alter alpha 6beta 4 integrin signaling, triggering cell death only when severe disruption of cell-BL attachment occurs.

Atopy May Be an Important Determinant of Subepithelial Fibrosis in Subjects with Asymptomatic Airway Hyperresponsiveness

The bronchial pathology of asymptomatic airway hyperreponsiveness (AHR) subjects is not well understood, and the role of atopy in the development of airway remodeling is unclear. The aim of this study was to evaluate whether atopy is associated with airway remodeling in asymptomatic AHR subjects. Five groups, i.e., atopic or non-atopic subjects with asymptomatic AHR, atopic or non-atopic healthy controls, and subjects with mild atopic asthma, were evaluated by bronchoscopic biopsy. By electron microscopy, mean reticular basement membrane (RBM) thicknesses were 4.3+/-1.7 micrometer, 3.4+/-1.8 micrometer, 2.5+/-1.5 micrometer, 2.6+/-1.1 micrometer, and 2.3+/-1.2 micrometer in the mild atopic asthma, atopic and non-atopic asymptomatic AHR, atopic and nonatopic control groups, respectively (p=0.002). RBM thicknesses were significantly higher in the mild atopic asthma group and in the atopic asymptomatic AHR group than in the other three groups (p=0.048). No significant difference in RBM thickness was observed between the atopic asymptomatic AHR group and the mild atopic asthma group (p>0.05), nor between non-atopic asymptomatic AHR group and the two control groups (p>0.05). By light microscopy, subepithelial layer thicknesses between the groups showed the same results. These findings suggest that RBM thickening occurs in subjects with atopic asymptomatic AHR, and that atopy plays an important role in airway remodeling.

Role of apoptosis in erosive and reticular oral lichen planus exhibiting variable epithelial thickness

Oral lichen planus (OLP) is a chronic inflammatory disease with different clinical types. Reticular and erosive forms are the most common. Although the cause of OLP remains speculative, many findings suggest auto-immune involvement, mediated by T lymphocytes against the basal keratinocytes. Inflammation, mechanical trauma or toxic agents can affect the epithelial homeostasia. Increased apoptosis may cause a decrease in epithelial thickness reflecting in the activity of the lesion. The objective of this study was to evaluate the occurrence of apoptosis and epithelial thickness in reticular and erosive forms of OLP. 15 samples of OLP each type (reticular and erosive) plus 10 of healthy mucosa were collected and processed. After morphometry, the apoptotic index and epitelial thickness were obtained. TUNEL and M30 CytoDEATH immunohistochemical assay were used to validate the morphologic criteria used. Apoptosis in the erosive OLP was significantly more intense than in the reticular type and both forms of OLP presented more apoptosis than the healthy oral mucosa. Healthy oral mucosa was thicker than both OLP forms and thicker in OLP reticular form than in the erosive one. The clinical differences between reticular and erosive forms of OLP are related to variations in epithelial thickness and in intensity of apoptosis.

O líquen plano oral (LPO) é uma doença inflamatória crônica com diferentes tipos clínicos. As mais comuns são as formas reticular e erosiva. Embora a causa do LPO permaneça no campo especulativo, muitos achados sugerem tratar-se de uma doença auto-imune, mediada por linfócitos T que têm como alvo os ceratinócitos basais. Inflamação, trauma mecânico ou agentes tóxicos podem afetar a homeostasia epitelial. O aumento da apoptose pode levar a uma diminuição da espessura epitelial e isto refletir na atividade da doença. O objetivo deste estudo foi avaliar a ocorrência de apoptose e a espessura epitelial nas formas reticular e erosiva de LPO. 15 amostras de LPO de cada tipo reticular e erosivo, além de 10 amostras de mucosa saudável foram coletadas e processadas. Depois da morfometria, o índice apoptótico (IA) e a espessura do epitélio foram obtidas. Reação de TUNEL e imunohistoquímica do M30 CytoDeath foram usadas para validação dos critérios morfológicos. A apoptose no LPO erosivo foi significativamente maior que no tipo reticular e ambas as formas de LPO apresentaram mais apoptose que a mucosa oral normal. A mucosa oral normal foi mais espessa que ambas as formas de LPO, sendo que, a forma reticular foi mais espessa que o tipo erosivo. As diferenças clínicas entre as formas reticular e erosiva de LPO têm relação com as variações na espessura epitelial e na intensidade da apoptose.

[Histopathological differentiation between well differentiated oral squamous cell carcinoma and oral verrucous carcinoma with special staining of basement membrane]

Microscopic differentiation between well differentiated squamous cell carcinoma and verrucous carcinoma is very difficult. As these lesions have different clinical course and treatment a reliable method to help distinguish between them is necessary. The basement membrane in oral verrucous carcinoma is generally intact whereas in oral squamous cell carcinoma is mostly discontinuous. This structure can be studied by different methods. The aim of this study was to differentiate these lesions with special staining of basement membrane. In this tests evaluation study, a total of 26 cases consisting of 15 oral squamous cell carcinomas and 11 oral verrucous carcinomas were retrieved from Cancer Institute of Imam Khomeini hospital archive of pathology and their paraffin blocks were cut and stained with Periodic Acid Schiff method. Slides were studied with light microscope to evaluate the continuity of basement membrane. Sensitivity and specificity of this method were calculated. The sensitivity of this method for differentiating oral squamous cell carcinoma from oral verrucous carcinoma was 100% whereas the specificity was 90.9%. Positive predictive value was 93.75% and negative predictive value 100%. Based on the results of this study, the sensitivity of this test for diagnosis of oral squamous cell carcinoma was high [100%]. Further studies are needed to evaluate the use this method for distinguishing oral verrucous carcinoma from oral squamous cell carcinoma

Asma en niños: aumento de la prevalencia y aspectos fisiopatológicos / Child with asthma: prevalence and physiopathological aspects

El asma representa la condición crónica inflamatoria más frecuente en niños y adolescentes. En nuestro medio se estima que al menos uno de cada siete niños sufre de asma; si bien en su mayoría son formas leves, su inicio ocurre en la niñez, manifestando su cronicidad en edad escolar. Existen muchos reportajes que describen su aumento, sin embargo, las razones de ellos aún permanecen en el área de la investigación. Esta breve revisión aborda aspectos generales epidemiológicos al celebrarse un aniversario mas del mes de mayo, como el mes del asma. Se describen aspectos básicos de la fisiopatología y su relación con factores como el ejercicio y la obesidad.

Gangliosides enhance migration of mouse B16-melanoma cells through artificial basement membrane alone or in presence of laminin or fibronectin.

The migration of B16LuF1 cells, B16-melanoma cells of lower metastatic potential to lung was enhanced through artificial basement membrane in presence of gangliosides of B16LuF1 cells as well as gangliosides of B16-melanoma cells of higher metastatic potential to lung, namely, B16LuF5 and B16LuF10 cells. The same concentration (50 microM) of gangliosides of B16LuF1, B16LuF5 and B16LuF10 cells gradually increased the migration of B16LuF1 cells through basement membrane. Moreover, B16LuF10 cell gangliosides modified the migratory effect of laminin and fibronectin on B16LuF1 cells. Laminin alone increased migration of B16LuF1 cells whereas fibronectin alone decreased migration of the same cells. When B16LuF10 cell gangliosides were used in combination with fibronectin, gangliosides removed the migration inhibitory effect of fibronectin resulting in net enhancing effect. Gangliosides in association with laminin also increased the enhancing effect of laminin on migration of B16LuF1 cells. Thus, gangliosides showed additive enhancing effect when used in combination with laminin. However, effect of individual gangliosides were different. Out of six gangliosides isolated from B16LuF10 cells only two gangliosides corresponding to standard gangliosides GM2 and GM3 enhanced migration of B16LuF1 cells. The migration of B16LuF1 cells in presence of each of the remaining four gangliosides corresponding to GT1b, GD1b, GD1a and GM1 was not altered and was comparable to that of untreated control. Thus, gangliosides of B16 melanoma cells alone or in combination with laminin or fibronectin enhanced migration of B16 melanoma cells through artificial basement membrane, suggesting possible role of tumor gangliosides during invasion of metastatic tumor cells through basement membrane of the surrounding tissues in vivo.

Histologic alterations of the basement membrane of the dermal and epidermal layers of the hoof in horses with acute laminitis

Fueron estudiadas las características morfológicas de los cascos de dos grupos de equinos. El primer grupo, conformado por cinco animales adultos, sin ninguna alteración clínica, correspondió al grupo control. El siguiente grupo, constituido por siete equinos recibieron 17,6g/kg de carbohidratos por vía oral, para la inducción de laminitis. De este grupo, 71 por ciento desarrolló la sintomatología entre 36 y 48 horas después de la administración del carbohidrato. Pasadas 48 h de la inducción de laminitis, los animales fueron sacrificados y sus miembros fueron retirados para realizar los respectivos estudios histológicos. Se efectuaron cortes histológicos de 5 a 7µm de grosor y, posteriormente, se tiñeron con hematoxilina-eosina (HE) y ácido peryódico de Schiff (PAS) para ser sometidos a microscopía óptica. A través de la coloración de HE, fue posible determinar alteraciones en la arquitectura de las láminas epidérmicas primarias y secundarias, las cuales se presentaron delgadas y anchas, con los núcleos de las células basales de forma arredondada y, eventualmente, localizados en su polo basal. La coloración por el PAS, permitió observar la membrana basal y la matriz proteica, separando las láminas epidérmicas y dérmicas y definiendo la morfología de éstas. En los equinos del grupo con laminitis se observaron deformación y fragmentación de la membrana basal. La utilización del PAS permitió determinar las alteraciones degenerativas graves en la membrana basal, de presentación precoz y coincidiendo con el desarrollo de los signos clínicos de claudicación.

Relationship between the morphologic alterations of vocal cords from adult autopsies and the cause of death

OBJETIVO: O objetivo deste trabalho foi identificar as possíveis alterações na espessura da membrana basal das cordas vocais e relacionar estas com a causa de morte. MÉTODO: Foram utilizadas laringes coletadas de adultos autopsiados, no período de 1993 até 2001. Realizamos as colorações da Hematoxilina- Eosina e Ácido Periódico de Schiff, onde foi medido o diâmetro da membrana basal. RESULTADOS: Foram analisadas 66 cordas vocais, o espessamento foi identificado em 14 casos (21,2 por cento), sendo encontrado em proporções iguais entre os sexos, sendo freqüente em pacientes da cor branca (12 casos, 85,7 por cento). Foram encontradas alterações respiratórias em 10 (71,4 por cento) dos casos com espessamento. Entre os pacientes intubados, 7 (18,4 por cento) apresentaram espessamento. Entre os fumantes 9 (19,63 por cento) apresentavam espessamento. Não houve influência estatisticamente significativa do espessamento na doença que levou o indivíduo à morte. CONCLUSÃO: Em relação a causa de morte não há diferença estatisticamente significante entre os casos cuja causa de morte foi por doenças respiratórias ou por doenças não respiratórias e o diagnóstico de espessamento da membrana basal das cordas vocais. Sua etiopatogênese necessita de maiores estudos.

Histopathological evaluation of placentas in IUGR pregnancies.

Gross and microscopic examination was conducted on one hundred placentas. These included twenty five normal controls and seventy five from intrauterine growth retardation (IUGR) pregnancies. Weight of the placentas from IUGR pregnancies were less than those of normal placentas. The incidence of infarction, intervillous fibrin deposition were much higher in IUGR placentas on gross examination. Highly significant increase in the incidence of infarction, intervillous fibrin deposition, stromal fibrosis and syncytial knotting were found in IUGR placentas compared to full term normal placentas on microscopic examination. The incidence of basement membrane thickening and cytotrophoblastic hyperplasis were also higher in IUGR placentas. All the major histologic findings pointed towards reduced blood flow to the placentas resulting in the restriction of blood flow to fetus. The information obtained from their examination can be a useful adjunct in planning and management of future pregnancies.

Diffuse Glomerular Basement Membrane Lamellation in Post-Transplant IgA Nephropathy

Diffuse glomerular basement membrane (GBM) lamellation, reminiscent of Alport's syndrome, has rarely, and exclusively, been reported in renal allografts from pediatric donors to adult recipients. We report on a similar lesion, identified in a 42-year-old male, who received a kidney from an unrelated 21-year-old living male donor. The disease of the recipient was unknown. Renal allograft biopsies were performed 3.5 and 4.8 years after the renal transplantation, due to massive proteinuria and serum creatinine elevation. The histological features of both biopsies were similar, but more advanced in the second biopsy. Glomerular mesangium was widened and had an IgA deposit in the first biopsy. In addition to the presence of mesangial electron dense deposits, the GBM showed diffuse lamellation and splintering on the subepithelial side, but no definite deposits. In the second biopsy, IgA deposits were extended to the peripheral capillary walls, but electron microscopic examination was not available. Two months after the second biopsy, the patient returned for hemodialysis.