Armando Martínez

Kinetic Profiles by Topographic Compartments in Muscle- Invasive Transitional Cell Carcinomas of the Bladder Role of TP53 and NF1 Genes

We evaluated 71 muscle-invasive transitional cell carcinomas (TCCs) of the bladder by tumor compartments. Kinetic parameters included mitotic figure counting, Ki-67 index, proliferation rate (DNA slide cytometry), and apoptotic index (in situ end labeling [ISEL] of fragmented DNA using digoxigenin-labeled deoxyuridine triphosphate and Escherichia coli DNA polymerase [Klenow fragment]). At least 50 high-power fields per compartment were screened from the same tumor areas; results are expressed as percentage of positive neoplastic cells. Mean and SD were compared by tumor compartment. DNA was extracted from microdissected samples (superficial and deep) and used for microsatellite analysis of TP53 and NF1 by polymerase chain reaction-denaturing gradient gel electrophoresis. Significantly higher marker scores were revealed in the superficial compartment than in the deep compartment. An ISEL index of less than 1% was revealed in 63% (45/71) of superficial compartments and 86% (61/71) of deep compartments. Isolated NF1 alterations were observed mainly in superficial compartments, whereas isolated TP53 abnormalities were present in deep compartments. Lower proliferation and down-regulation of apoptosis define kinetically the deep compartment of muscle-invasive TCC of the bladder and correlate with the topographic heterogeneity, NF1-defective in superficial compartments and TP53-defective in deep compartments.

Differential kinetic features by tumour topography in cutaneous small-cell neuroendocrine (Merkel cell) carcinomas

Background/Objectives  Merkel cell carcinomas (MCC) reveal epithelial and neuroendocrine differentiation, but its topographic cell kinetics remains unknown. This study analyses proliferation, apoptosis, and DNA ploidy by topography, features that can help planning therapeutic protocols. This study topographically analyses proliferation, apoptosis, and DNA ploidy.

Dural cavernous haem angioma of the anterior cranial fossa

Extra-axial cavernous haem angiomas are uncommon lesions histologically identical to cavernomas in other locations. However, their radiological features and clinical behaviour may differ. They are frequently misdiagnosed preoperatively, as they often mimic other tumours. We describe a patient suffering from loss of the sense of smell, due to a cavernous haemangioma implanted in the dura mater of the anterior cranial fossa close to the olfactory bulb. To our knowledge, this is the first patient reported with such a lesion.

Spinal cord and brain glioblastoma multiforme without previous craniotomy

The frequency of symptomatic spinal cord metastases from brain glioblastoma multiforme (GBM) is between 1.3 and 8.8%. In almost all cases, there has been a history of surgical manipulation or radiation therapy that might have altered the blood‐brain barrier and introduced tumor cells through the cerebrospinal fluid pathways. The interval between the intracerebral GBM and its intramedullary metastasis is 12‐14 months and the mean survival time, under this condition, never exceeds 6 months.2‐4 However, in the absence of previous surgery or radiotherapy, it is difficult to distinguish between true metastasic from multicentric central nervous system GBM, as occurred in our case. 1‐4 A 52-year-old woman presented with a 2-month history of cervical pain and numbness in the left upper extremity; she was admitted with progressive paraparesis and acute urinary retention. Cervical magnetic resonance (MR) imaging demonstrated an intramedullary C4‐6 mass, which enhanced after Gd injection (Fig. 1). The tumor was resected after cervical laminectomy. Histopathological examination revealed that the lesion was a GBM. Considering this diagnosis, we performed brain MR imaging 1 week after the spinal cord surgery and discovered an enhancing mass, 2 cm in diameter, located in the right atrium (Fig. 2). Twenty days after the initial surgery, the intracerebral lesion was resected and its histopathological features were also consistent with a GBM.

Early changes in the Schwann cells in experimental allergic neuritis

Experimental allergic neuritis (EAN) was induced in guinea-pigs by intradermal injection of rabbit peripheral nerve emulsified in Freunds adjuvant. Both sciatic nerves were obtained between 12--24 hr after clinical symptoms were evident. Several fascicles from each nerve were isolated for histochemical studies with NADH-diaphorase (NADH) and acid phosphatase (AP) applied to teased nerve fibres. Small pieces were processed for electron microscopy, and a fascicle was teased after staining with osmium tetroxide. In isolated nerve fibres stained with histochemical techniques myelin lesions of segmental character were found closely related to inflammatory cells; Schwann cell cytoplasm in contact with mononuclear cells showing a heavy enzymatic activity (NADH and AP). Under polarized light, the underliying myelin showed focal loss of birefringence. Some electron-microscopic pictures suggested active myelin breakdown by mononuclear cells. The possibility of primary Schwann cell damage by mononuclear cells with subsequent demyelination is discussed.

Genetic alterations of IDH1 and Vegf in brain tumors

This study evaluates the presence of R132H mutation in isocitrate dehydrogenase (IDH1) gene and the vascular endothelial growth factor (VEGF) +936 C/T polymorphism in brain tumors. The impact of these genetic alterations on overall survival (OS) and progression free survival (PFS) was evaluated.

Intestinal mucosal changes following induced hypothyroidism in the developing rat.

In this study, morphological changes which occur in the small intestine of hypothyroid rats are described. Hypothy roidism was induced during the first 24 h postnataly. — Samples from duodenojejunal and ileocecal junctions were taken, and histologic, histomorphometric, and ultrastructural studies were performed. The most prominent feature was the decrease of the villous height and total mucosal thickness. At electron microscopic level, microvillous height was also markedly decreased. These changes probably represent a direct effect of hormonal deprivation upon the intestinal mucosa, combined with the effect that hypothyroidism may have on the villi.