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Biomedical subjects

N Reissenweber

Publications and source records attributed to N Reissenweber.

12 recordsLinked to original sources
PubMed1999

Adrenergic innervation in reactive human lymph nodes.

Several experimental models have demonstrated that the central nervous system is functionally linked to the immune system by means of the autonomic nervous system. Samples of 36 lymph nodes of patients whose ages ranged from 16 to 69 y were studied. In order to demonstrate the existence and distribution of sympathetic nerve fibres, a polyclonal antibody antityrosine hydroxylase (TH), with the streptavidin-biotin system of detection, was used. TH-positive nerve fibres appeared in all reactive patterns of the lymph nodes studied. Thin nerve fascicles ramified at the hilar region and also in the connective tissue septae. Adventitial adrenergic nerve fibres were found following afferent, and to a lesser extent, efferent blood vessels. Another source of incoming nerve fibres was found at capsular level, accompanying blood vessels. On the arterial side, the innervation ceased before reaching the follicular arterioles. Our demonstration of innervation in postcapillary venules could support a regulatory role of adrenergic neurotransmitters in lymphocyte traffic. Occasional nerve fibres were also seen in T areas among parenchymatous cells. These findings confirm the existence of sympathetic innervation in human lymph nodes, and provide indirect evidence that the psychoneuroimmune axis could also exist in humans.

Adolescent↗
PubMed1998

The interrelationship between tubular and papillary sectors of tubulo-villous colorectal adenomas: comparative morphometric analysis and evaluation of cell proliferation.

In a series of 100 colorectal adenomas, 23 tubulo-villous adenomas were individualized through the identification of papillae as structures persisting for more than 100 microm in serial sections with a connective axis lined with epithelial cells. In these adenomas, the tubular and villous areas with the highest dysplasia were selected, and a morphometric analysis was undertaken to assess the Index of Structural Atypia, the Nucleo-Glandular Index, and the Nuclear Stratification Index. The AgNor count and the proliferating cell nuclear antigen (PCNA) Label Index (LI) also were performed. The overall mean of each of these indexes was significantly higher in the villous sector than in the tubular one (P < .001). In 16 cases, the semi-objective method of dysplasia gradation showed a superior degree in the papillary sector, whereas it showed an equal degree in the remaining seven lesions. The AgNOR count was significantly different in all cases, with higher values in villous sectors (P < .05). With the exception of one case, this was confirmed by the PCNA LI. The Stratification Index showed significantly different values in 20 cases, whereas the other morphometric indexes showed a less discriminatory result. Our findings objectively show that the degree of dysplasia in tubulo-villous adenomas should be analyzed in the villous sector. The existence of heterogeneous cellular populations has been confirmed both in the structural organization of cells and in some basic parameters such as the cell proliferation rate in colorectal adenomas. Our findings suggest that the occurrence of villous architectural growth is a secondary event in a tubular adenoma. Enhanced cellular proliferation of the villous area allows the progressive substitution of tubular structures.

Adenoma, Villous↗
PubMed1997

Localized myofibroblastic proliferation in the neck of a patient with an IgG myeloma.

We describe a myofibroblastic proliferation in the neck and lower part of the face involving skin and muscle of a 68-year-old female patient with an IgG kappa myeloma. Biopsies showed a fusocellular proliferation with scarce pseudoganglion cells involving the superficial fascia and the cutaneous muscle of the neck. The proliferative cells showed immunohistochemical and ultrastructural features characteristic of myofibrobasts with a proliferating cell nuclear antigen index of 48%; 42% of the cells displayed HLADR-positive membrane staining. Cellular proliferation subsided following the use of immunosuppressive drugs. Eight months after initial consultation, the patient developed polymyositis without a proliferative component and died of aplastic anemia.

Aged↗
PubMed1995

[Primary small cell carcinoma of the esophagus].

Primary small cell carcinoma of the esophagus, morologically indistinguishable from its counterpart of the lung is a rare tumour with a frequency between 0.05 to 7.6% of all esophageal malignancies. Currently they are divided into oat cell and non oat cell, regarding the presence of neuroendocrine granules. We report 3 cases from our hospital. They were studied clinicopathologically and also examined by electron microscopy.

Aged↗
PubMed1995

[Quantitative evaluation of juxtatrabecular fibrosis in myelodysplastic syndromes].

PURPOSE: Myelofibrosis is a common, poor-prognosis feature of myelodysplastic syndromes (MDS). The aim of this work was to evaluate quantitatively the extent of the juxtatrabecular fibrosis in primary MDS and in secondary myelodysplasias, along with the presence of immature precursor cells in anomalous position, that is, the displacement of granulopoiesis from the paratrabecular area to central positions. PATIENTS AND METHODS: Twenty-seven bone marrow samples were examined: 9 from primary MDS, 9 from secondary myelodysplasias, and 9 normal. The percentage of myeloblasts and promyelocytes with nucleoli located in the central areas was estimated, in an attempt to correlate such feature with the degree of juxtatrabecular fibrosis. The analysis of data was performed with the Kruskal-Wallis test, values of p < 0.01 being significant. RESULTS: Sectorial juxtatrabecular fibrosis was present in all the myelodysplastic samples, ranging from 6% to 55% of the trabecular surface; the highest values found in the controls were about 3.6% (p < 0.01). Although the juxtatrabecular fibrosis figures are higher in secondary MDS, the difference is not significant with regard to the primary MDS in the number of patients studied here. The count of myeloblasts and promyelocytes with nucleoli present in the MDS was significantly greater than that of the control group. The number of promyelocytes with nucleoli was significantly higher in the primary MDS with respect to the secondary ones, whereas no significant difference was seen between the two types of MDS regarding the myeloblast count. CONCLUSIONS: The increased number of central immature precursor cells in MDS was not directly correlated with the extent of the juxtatrabecular fibrosis. Although the number of cases is small, the fact that the juxtatrabecular fibrosis was higher in the two deceased patients in the series (49% and 56%, respectively) suggests a poor-risk prognosis for such finding.

Anemia, Refractory↗
PubMed1994

[Endoscopic-pathologic correlation of rectocolonic lesions less than 10 mm].

Ninety eight rectocolonic lesions up to 10 mm in diameter found in 50 patients were analyzed. The relationship between endoscopic and pathologic diagnosis was established. Emphasis was made on the detection of adenomas based in the following: Yamada III or IV lateral vision, Yamada I and II with smooth but erythematous surface, and in pale with irregular surface lesions. The sensitivity of the method was 92% and the specificity was 72% for adenomas. Six percent of adenomas were pale, with mucous hypersecretion on histopathology, and can be mistaken for hyperplastic polyps. This mucous hypersecretion correlates with low grade dysplasia, which supposedly indicates a lower evolutive risk.

Adenoma↗
PubMed1994

[Early gastric carcinoma in Uruguay].

This report comprises all early gastric carcinomas (EGCs) submitted to surgery in Uruguay from 1972 to 1989. The EGC definition and type classification have been carried out according to the guidelines of the Japanese Research Society for Gastric Cancer. We have included 25 personal cases and also several other cases on the basis of the information provided by other pathologists. We have had frequent access to the microscopic slides for revision as well. 15 cases were discarded due to inadequacy of sampling of the surgical specimen. 69 EGCs were detected in the surgical specimens of 64 patients. Three patients showed a second independent EGC while one showed three lesions. The most frequent endoscopic types were: type IIc (slightly depressed) 36.2%, type IIc + III (combined type, depressed + ulcerated) 29% and type I (protruding type) 18.8%. Three were classified as minute EGCs (5mm or less in diameter). 39 lesions showed neoplastic cells only in the mucosa (m type) whereas 30 invaded the submucosal layer (sm type). EGC's with a diameter of 10 mm (or less) showed at the microscopical level only two histological types: tubular well-differentiated adenocarcinoma (intestinal type) or signet ring cell carcinoma. When the ratio of EGC's versus advanced carcinomas was studies reviewing the pathological files of the Hospital de Clínicas, we found the EGC percentage increased continuously from 1981 to 1989. The median value was 16.6%. This evidence indicates an improvement in the early detection of gastric cancer concomitant with the better training of endoscopists. However, the medial value decreased to 4.9% when specimens from the whole country were considered.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1982

[Anaplastic carcinoma of the thyroid: early clinical and histopathological stages. Therapeutic implications (author's transl)].

Anaplastic carcinoma of the thyroid is generally considered a primary condition. Our study, based on ten observations, shows that anaplastic carcinoma of the thyroid with a rapidly fatal course may arise in long-standing goiters. Borderline histologic changes may be encountered; in some differentiated nodules, undifferentiated areas were found. Factors inducing transformation is equally obscure. Anaplastic changes may result from the growth of previously quiescent clones. The time-interval between benignant and malignant lesions varies widely and is difficult to establish unequivocally. In some instances, anaplastic carcinoma occurs after surgical removal of differentiated carcinoma.

Adult↗
PubMedDate not supplied

Van der Woude syndrome. A case report.

We describe several members of a family with Van der Woude syndrome, a genetic and congenital malformation syndrome with autosomal dominant inheritance and 70% to 80% penetrance with variable expressivity. It is characterized by clinical signs localized to the face, such as bilateral or unilateral pits on conical elevations in babies or extensive depressions in adults, both in the vermilion border of the lower lip, with cleft lip, with or without cleft palate and uvula. Small accessory or heterotopic salivary glands empty into sinuses or fistulas in the lips. This eight member family had various clinical signs of the condition. All had cleft lip and palate. We studied the major characteristics of the eight patients and describe histopathologic and immunohistochemical features.

Cleft Lip↗