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Biomedical subjects

R Sen Gupta

Publications and source records attributed to R Sen Gupta.

10 recordsLinked to original sources

[Progressive paralysis caused by radiation-induced cervical malignant peripheral nerve sheath tumor].

HISTORY AND DIAGNOSIS: A 59-year old engineer was admitted to the hospital because of pain in his right collar region and the onset of incomplete paresis of the right arm. Magnetic resonance tomography displayed an advanced tumour arising from the right paravertebral soft tissue. Histological examination revealed a malignant peripheral nerve sheath tumor (MPNST). Thirteen years before admission, the patient had a right-sided tumor-tonsillectomy of a squamous cell carcinoma and local radiation of a cystic squamous cell carcinoma in the ipsilateral cervical soft tissue. CLINICAL COURSE AND THERAPY: In the following course, progressive neurological symptoms occurred including beginning paraplegia, right phrenic paralysis and a severe concomitant pain syndrome. Due to the location and advanced tumor state, surgical treatment was not performed and palliative chemotherapy remained ineffective. Three months later the patient died due to rapidly progressive neurological failure. CONCLUSION: MPNST represents a rare entity which has been related to postoperative radiation. Unusual neurological symptoms in anatomical regions of former radiation should therefore include neurogenic secondary malignancies in the differential diagnosis for early surgical intervention.

Arm↗

HOPE-fixation enables improved PCR-based detection and differentiation of Mycobacterium tuberculosis complex in paraffin-embedded tissues.

Standard PCR-based detection of mycobacterial DNA in paraffin-embedded specimens may lack sufficient sensitivity because of the degradation of nucleic acids caused by routinely used formalin fixation. Therefore, we set up an approach that aimed at improving the results by applying the novel HOPE-fixative in PCR-detection of mycobacteria in paraffin-embedded tissues. Comparison of PCR-results using DNA extracted from either HOPE- or formalin-fixed specimens in BCG-infected SCID-mice revealed a more than 100fold enhanced sensitivity for the HOPE-fixed material. Owing to the preservation of DNA from degradation in HOPE-fixed tissues, even differentiation within the M. tuberculosis complex was possible by spoligotyping. We therefore conclude that the HOPE-fixative is a useful tool for molecular pathology that enhances the sensitivity of PCR-based methods for the detection of pathogens in paraffin-embedded tissues compared to formalin-fixation. Owing to the better preserved DNA, improved differentiation of mycobacteria from archived materials is possible. These results promise new and a substantially wider range of possibilities in the field of molecular pathology.

Animals↗

[Inflammatory fibroid polyps of the gastrointestinal tract].

Inflammatory fibroid polyps of the gastrointestinal tract represent a relatively rare entity. Although the histopathological classification, the etiology and the pathogenesis of this lesion remains unclear, the biological dignity is commonly understood as benign. Nevertheless, these polyps are able to cause gastrointestinal bleeding, intestinal obstruction or intussusception which often provides the indication for surgical treatment. In endoscopical biopsies unexpected difficulties for the pathologist may arise from the fact that these uncommon lesions often show a submucosal growth pattern. With reference to two case reports, the clinical, diagnostic and histopathological aspects of inflammatory fibroid polyps will be discussed. An additional literature review of the etiology, immunohistochemistry and differential diagnosis is presented.

Aged↗

Effect of atenolol on cadmium-induced testicular toxicity in male rats.

Cadmium-induced stress adversely affects testicular activity and causes sympathetic stimulation. To investigate the effect of atenolol, a beta-adrenergic receptor blocker, on testicular androgen synthesis after cadmium treatment, adult Sprague-Dawley strain male rats were given a single sc dose of cadmium chloride 0.45 mg/kg BW. Animals were killed on day 3 after treatment. Adrenal weight, adrenal delta 5-3 beta-hydroxysteroid dehydrogenase (delta 5-3 beta-HSD) activity, serum corticosterone, and brain noradrenaline were increased significantly while testicular delta 5-3 beta-HSD and 17 beta-HSD activities, serum testosterone, and accessory sex organs weight were decreased. Oral coadministration of atenolol at a dose of 2.0 mg/kg body weight for 3 days resulted in complete protection of adrenal delta 5-3 beta-HSD, testicular delta 5-3 beta-HSD, and 17 beta-HSD activities, adrenal weight, serum corticosterone, and serum testosterone when compared with cadmium-only group and there were no significant differences in these parameters from the vehicle control values. Simultaneous administration of cadmium and atenolol also protected brain noradrenaline content and reduced the rise of testicular cadmium concentration. All the parameters were similar to control levels in rats treated with atenolol alone. We conclude that atenolol may protect testicular androgen synthesis by inhibiting the action of noradrenaline on testicular Leydig cells and adrenocortical hyperactivity in cadmium-treated rats.

17-Hydroxysteroid Dehydrogenases↗

HOPE--a novel tool for the pathologist.

The growing demand for the detection of prognostic and diagnostic biomarkers by application of molecular-biological techniques has been slowed down to a large degree by the use of formalin and its influence onto antigenic structures and nucleic acids, although other reasons also exist. With regard to morphology a limitation in the possibilities, compared to frozen sections, takes place. With the introduction of the HOPE (Hepes glutamic acid buffer mediated Organic solvent Protection Effect) -fixation to date both have become possible; substantially enlarged possibilities concerning the detection of DNA, RNA and proteins in combination with excellent morphological results comparable to formalin-fixed tissues. We also highlight some aspects from our lung specific work during the last years. Immunohistochemical markers for differential diagnostics of malignancies in the lungs are discussed; their enhanced detectability using the HOPE-technique is pathbreaking for the future. The same holds true for the substantially enhanced detectability of germs (e.g. mycobacteria) in HOPE-fixed tissues.

Buffers↗