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Biomedical subjects

A Singal

Publications and source records attributed to A Singal.

30 records · Page 2Linked to original sources
PubMed1998

Developmental remodeling and shortening of the cardiac outflow tract involves myocyte programmed cell death.

The embryonic outflow tract is a simple tubular structure that connects the single primitive ventricle with the aortic sac and aortic arch arteries. This structure undergoes a complex sequence of morphogenetic processes to become the portion of the heart that aligns the right and left ventricles with the pulmonary artery and aorta. Abnormalities of the outflow tract are involved in many clinically significant congenital cardiac defects; however, the cellular and molecular processes governing the development of this important structure are incompletely understood. Histologic and tissue-tagging studies indicate that the outflow tract tissues compact and are incorporated predominantly into a region of the right ventricle. The hypothesis tested in the current study was that cell death or apoptosis in the muscular portion of the outflow tract is an important cellular mechanism for outflow tract shortening. The tubular outflow tract myocardium was specifically marked by infecting myocytes of the chicken embryo heart with a recombinant replication-defective adenovirus expressing beta-galactosidase (beta-gal) under the control of the cytomegalovirus promoter. Histochemical detection of the beta -gal-labeled outflow tract myocytes revealed that the tubular structure shortened to become a compact ring at the level of the pulmonic infundibulum over several days of development (stages 25-32, embryonic days 4-8). The appearance of apoptotic cardiomyocytes was correlated with OFT shortening by two histologic assays, TUNEL labeling of DNA fragments and AnnexinV binding. The rise and fall in the number of apoptotic myocytes detected by histologic analyses paralleled the change in activity levels of Caspase-3, a protease in the apoptotic cascade, measured in outflow tract homogenates. These results suggest that the elimination of myocytes by programmed cell death is one mechanism by which the outflow tract myocardium remodels to form the proper connection between the ventricular chambers and the appropriate arterial trunks.

Adenoviridae↗
PubMed1990

Ulcers after intravariceal sclerotherapy: correlation of symptoms and factors affecting healing.

Esophageal variceal ulcers have been held responsible for most postsclerotherapy complaints. To investigate a possible relation between these ulcers and symptoms, we followed for 4 weeks 40 patients with portal hypertension who had received a single course of intravariceal sclerotherapy. All 40 patients were found to have mucosal variceal ulcers on the day after sclerotherapy. One or more symptoms were given by 26 (65%) patients; dysphagia by 53% (mean duration 4.6 +/- 2.2 days), retrosternal pain by 28% (mean duration 3.0 +/- 2.5 days), and fever by 15% (mean duration 2.1 +/- 0.4 days). A gastric variceal ulcer was responsible for bleeding in one (2.2%) patient. We found no correlation between the occurrence and duration of symptoms and the presence of variceal ulcers. While symptoms were transient, ulcers persisted for several days to weeks in most patients. Patients who had received a higher amount of sclerosant developed larger ulcers (greater than 1 cm) with more symptoms and healing was more delayed than in those who had received lesser amounts and developed smaller ulcers (less than 1 cm). In patients with a serum albumin level greater than 3.0 g/dl, ulcers healed more often than in those with a less than 3.0 g/dl albumin (72 versus 18%, p less than 0.05). Development of mucosal ulcers is a natural consequence of intravariceal sclerotherapy and it appears unrelated to symptoms. The chemical nature and the volume of the injected sclerosant are probably responsible for the symptoms after sclerotherapy. Further, postsclerotherapy ulcers heal spontaneously, more often in patients with good nutritional status.

Esophageal Diseases↗
PubMed1988

Evaluation of the incidence and significance of the "mosaic pattern" in patients with cirrhosis, noncirrhotic portal fibrosis, and extrahepatic obstruction.

Mosaic pattern of gastric mucosa has been reported to be a sensitive and specific criterion for the diagnosis of portal hypertension and an important marker of nonvariceal upper gastrointestinal bleeding. So that the validity of this endoscopic sign could be assessed, 136 patients with portal hypertension, 25 chronic alcoholics without portal hypertension, and 366 controls were carefully endoscoped. Mosaic pattern was significantly (p less than 0.01) more common in portal hypertension patients (7.4%) than in controls (1.4%). It was not seen in chronic alcoholics. The incidence of mosaic pattern was 10.9% in cirrhotics, 2.9% in noncirrhotic portal fibrosis, and 5.4% in extrahepatic portal obstruction patients; the differences were not significant. Mosaic pattern was significantly (p less than 0.01) more often seen in postsclerotherapy (13.8%) than in presclerotherapy patients (2.6%). Bleeding from nonvariceal causes was uncommon, and was seen in only one patient (0.8%) showing mosaic pattern. Endoscopic gastric biopsies from areas showing mosaic pattern did not reveal any vascular abnormalities. In conclusion, gastric mucosal lesions are not very common in Indian patients with portal hypertension. In our experience, "mosaic pattern" is not a useful diagnostic feature in portal hypertension patients.

Adolescent↗
PubMedDate not supplied

Corrosive oesophageal strictures following acid ingestion: clinical profile and results of endoscopic dilatation.

There are several reports on oesophageal strictures caused by alkali ingestion, but information on oesophageal strictures due to acid ingestion is scarce. Endoscopic dilatation, which has been found to be quite safe and effective in the treatment of benign oesophageal strictures of other aetiology, has also not been evaluated adequately in the treatment of these strictures. Over a period of 2 years, of 47 patients treated at this centre of benign oesophageal strictures, 17 (36.2%) patients had strictures following ingestion of corrosive agents. Thirteen patients had ingested acids and only four gave a history of alkali ingestion. The age range of these 13 patients was 14-50 years (mean = 25.5 years, s.d. = 2.6). The amount of acid ingested varied from 10 to 100 ml (median = 50 ml). The interval between acid ingestion and presentation to hospital ranged from 1 to 60 months (median = 2 months). Ten patients had multiple strictures, and the most common site of involvement was the upper third followed by the lower third of the oesophagus. Only five of these 13 patients had evidence of gastric involvement in the form of antral stricture (four) and hour glass deformity (one). Strictures were dilated using Eder-Puestow metal olives passed over a guide wire. The total number of sittings required to achieve adequate dilatation in this group ranged from 1 to 30 (median = 14). Most patients were managed successfully with dilatation (good response 63.6%, satisfactory response 18.2%). On follow-up, recurrence of dysphagia was seen in a high number of patients (66%), but this could be managed easily with repeat dilatation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Eyelid involvement in disseminated chronic cutaneous lupus erythematosus.

Eye involvement in chronic cutaneous lupus erythematosus (CCLE) has been reported infrequently. We describe two cases of disseminated CCLE, a 50-year-old woman and a 45-year-old man, with eyelid involvement and disease duration of 4 and 20 years respectively. The first patient showed an excellent response to chloroquine while there was lack of response in the second patient.

Eyelid Diseases↗
PubMedDate not supplied

Involvement of genitofemoral nerve with genital lesions in lepromatous leprosy.

The case of a male patient diagnosed to have lepromatous leprosy with type 2 reaction on multibacillary multidrug therapy, with unusual, widespread involvement of genitalia in the form of plaque and nodules of leprosy over scrotum and perimeatal region of glans, necrotic lesions of erythema nodosum leprosum over scrotum, neuritis of genital branch of genitofemoral nerve bilaterally, and azoospermia, is reported.

Genitalia, Male↗
PubMedDate not supplied

Lepromatous leprosy with bilateral facial nerve palsy and hyperthyroidism.

Bilateral lagophthalmos secondary to facial nerve is extremely uncommon. Further, the aetiology in most of these cases is of central origin unlike the peripheral involvement in leprosy. A patient of lepromatous leprosy (LL) may be euthyroid or hypothyroid on account of leprous involvement of the thyroid gland. A case of LL with bilateral lagophthalmos and hyperthyroidism is reported.

Adult↗