PubMed Health⌕ Search

Biomedical subjects

M Goyal

Publications and source records attributed to M Goyal.

At least 19 recordsLinked to original sources
PubMed2002

The molecular epidemiology of tuberculosis in inner London.

The study used DNA fingerprint typing (spoligotyping and Heminested-lnverse-PCR) of Mycobacterium tuberculosis from all culture-confirmed inner London patients over a 12-month period to describe transmission. The methodology was evaluated by comparison with standard IS6110 typing and by examining its ability to identify known household clusters of cases. Isolates sharing indistinguishable typing patterns using both techniques were defined as clustered. Clusters were investigated to identify epidemiological links. The methodology showed good discriminatory power and identified known household clusters of cases. Of 694 culture-confirmed cases, 563 (81%) were typed. Eleven (2%) were due to laboratory cross-contamination and were excluded. Of the remaining 552 isolates 148 (27%) were clustered. Multivariate analysis indicated that clustering was more common in those with pulmonary smear positive disease (P < 0.02); those born in the United Kingdom (P < 0.0003) and in patients living in south London (P = 0.02). There was also a trend towards clustering being more common in those not known to have HIV infection (P = 0.051). The results suggest that in inner London, recent local transmission makes an important contribution to notification rates.

Adolescent↗
PubMed2001

Nitric oxide binding to oxygenated hemoglobin under physiological conditions.

We have added nitric oxide (NO) to hemoglobin in 0.1 M and 0.01 M phosphate buffers as well as to whole blood, all as a function of hemoglobin oxygen saturation. We found that in all these conditions, the amount of nitrosyl hemoglobin (HbNO) formed follows a model where the rates of HbNO formation and methemoglobin (metHb) formation (via hemoglobin oxidation) are independent of oxygen saturation. These results contradict those of an earlier report where, at least in 0.01 M phosphate, an elevated amount of HbNO was formed at high oxygen saturations. A radical rethink of the reaction of oxyhemoglobin with NO under physiological conditions was called for based on this previous proposition that the primary product is HbNO rather than metHb and nitrate. Our results indicate that no such radical rethink is called for.

Blood↗
PubMed2001

Tubercular pseudoaneurysms of aorta.

BACKGROUND: Tubercular pseudoaneurysm of aorta is a rare but important complication of tuberculosis. With worldwide resurgence of tuberculosis due to increasing incidence of drug-resistant tuberculosis and its association with acquired immunodeficiency syndrome, the tubercular pseudoaneurysm has become a real clinical entity. METHODS: In the past 3 years, 5 young patients (22 to 40 years) presented with tubercular pseudoaneurysm. Site of involvement included ascending aorta, distal aortic arch, proximal descending thoracic aorta, distal descending thoracic aorta, and infrarenal abdominal aorta. Two patients had macroscopic focus of tuberculosis in the nearby vicinity, and all 5 patients had evidence of active/treated pulmonary pericardial tuberculosis. All patients either had received antitubercular therapy previously or were receiving it at the time of presentation. Rapid deterioration in the clinical status was the most marked clinical feature. All patients underwent operation. Graft interposition was performed in 2, patch repair in 2, and direct closure of the rent was performed in 1 patient. All 5 patients received antitubercular therapy in the postoperative period. RESULTS: All patients survived the operation and were discharged from the hospital. One patient developed recurrence at the original site after 8 months and died at reoperation. The remaining patients are symptom free at 18 to 36 months postoperatively. CONCLUSIONS: A combination of chemotherapy and operation yields gratifying results for the treatment of tubercular pseudoaneurysm.

Adult↗
PubMed2001

Overexpression of heat-shock proteins reduces survival of Mycobacterium tuberculosis in the chronic phase of infection.

Elevated expression of heat-shock proteins (HSPs) can benefit a microbial pathogen struggling to penetrate host defenses during infection, but at the same time might provide a crucial signal alerting the host immune system to its presence. To determine which of these effects predominate, we constructed a mutant strain of Mycobacterium tuberculosis that constitutively overexpresses Hsp70 proteins. Although the mutant was fully virulent in the initial stage of infection, it was significantly impaired in its ability to persist during the subsequent chronic phase. Induction of microbial genes encoding HSPs might provide a novel strategy to boost the immune response of individuals with latent tuberculosis infection.

Animals↗
PubMed2001

Podocyte depletion and glomerulosclerosis have a direct relationship in the PAN-treated rat.

BACKGROUND: Podocytes are highly differentiated glomerular epithelial cells with limited potential to divide. They are responsible for maintaining and supporting the glomerular basement membrane so as to facilitate efficient filtration. The hypothesis tested was whether the development of glomerulosclerosis in the puromycin aminonucleoside (PAN)-treated rat could be attributed to podocyte depletion. METHODS: PAN was injected in Sprague-Dawley rats once, twice, or three times at 30-day intervals. Podocytes were counted in glomeruli using immunoperoxidase histochemistry and antibodies to both GLEPP1 (PTPRO) and WT-1. Podocytes were assayed in urine using reverse transcription-quantitative polymerase chain reaction (RT-QPCR). Glomerular areas were measured by computerized morphometry. RESULTS: In a preliminary experiment, a single injection of PAN caused a reduction in the glomerular podocyte count by 25%. Additional independent confirmation that podocytes were lost from glomeruli after PAN injection was obtained identifying detached podocytes in Bowman's space, measurement of nephrin and GLEPP1 mRNAs in urine, ultrastructural analysis of glomeruli, and identification of TUNEL-positive apoptotic podocytes in glomeruli. In a second experiment, sequential podocyte depletion by 15, 31, and 53% was achieved by the administration of one, two, or three injections of PAN at 30-day intervals. The region of the glomerulus devoid of podocytes developed glomerulosclerosis, and this area progressively increased as podocytes were progressively depleted. The correlation coefficient (r(2)) value for the relationship between percent podocyte depletion and glomerulosclerotic area was 0.99. The Y intercept of this plot showed that glomerulosclerosis was initiated when only 10 to 20% of podocytes were lost. CONCLUSION: This report supports the growing body of data linking glomerulosclerosis directly to a reduction in relative podocyte number [increased glomerular area per podocyte (GAPP)]. It raises important questions related to the mechanisms of podocyte loss, strategies for prevention of podocyte depletion, and the prevention of progression of glomerular diseases.

Animals↗
PubMed2001

The tau sign.

Explore the source record for details and available documents.

Cerebral Arteries↗
PubMed2000

Sonographic appearance of the Angelchik prosthesis.

The Angelchik prosthesis is a silicone-filled, doughnut-shaped device used for the surgical treatment of gastroesophageal reflux. This device appears on sonograms as a C-shaped, hypoechoic structure with nonspecific Doppler waveforms. Because the Angelchik prosthesis is rarely used anymore, recently trained sonographers and radiologists may misinterpret this sonolucent appearance as an unusual vascular lesion. We report a case of an Angelchik prosthesis that was incidentally noted at the gastroesophageal junction on a routine abdominal sonographic examination.

Aged↗
PubMed2000

Adenocarcinoma arising in interposed colon: report of a case.

A rare occurrence of primary adenocarcinoma arising in an interposed colon nearly seven years after the surgery is described. Remarkably, there were no symptoms from a large mass in the transposed bowel. Diagnosis was made fortuitously while searching for the cause of the patient's iron-deficiency anemia. The rationale for careful preoperative screening of the colonic segment intended for transplant to exclude pre-existing pathology is reemphasized. The various methods of evaluating the postoperative colon graft and their advantages and limitations are discussed.

Adenocarcinoma↗
PubMed2000

Malignant pleural mesothelioma in a 13-year-old girl.

Pleural mesothelioma is an uncommon tumor in all age groups, but is especially rare in childhood. We describe the clinical and radiological features of malignant pleural mesothelioma in a 13-year-old girl. The chest radiograph showed nearly complete opacification and loss of volume in the left hemithorax. Computed tomography demonstrated a large pleural effusion centrally surrounded by a thick enhancing rind of soft tissue. The radiological features of childhood pleural mesothelioma in our case were similar to those described in adults with this disease.

Child↗
PubMed2000

Disseminated lymphangiomatosis presenting with massive chylothorax.

BACKGROUND: Lymphangiomatosis is a disease characterized by involvement of various body constituents and can involve the skeletal system, connective tissues, and visceral organs. MATERIALS AND METHODS: We present a case of a 9-year-old girl where this entity presented with extensive right-sided chylothorax. Conventional imaging, including skeletal scintigraphy and contrast enhanced CT of the chest and abdomen, may have underestimated the extent of the disease, as seen on follow-up T2-weighted MR images of the chest and abdomen in our case. RESULTS: MRI easily demonstrated additional bone lesions as well as multiple small splenic lesions, which were difficult to appreciate on prior CT examinations. CONCLUSION: We suggest that MRI may be helpful to assess the extent of this disease more accurately.

Bone Neoplasms↗
PubMed2000

How residents spend their nights on call.

PURPOSE: Night call is a significant part of residents' education, but little information about their night-call activities is available. This study recorded residents' activities during night-call rotations on internal medicine and pediatrics wards. METHOD: In June and July 1997, on-call pediatrics and internal medicine residents at an urban academic medical center were accompanied by trained observers on the general wards between the hours of 7 PM and 7 AM. The types and duration of activities were recorded. RESULTS: Residents were observed for 106 nights. Internal medicine and pediatrics residents spent their time similarly. They spent 5.3 hours and 5.7 hours per night, respectively, on "basic" activities such as eating, resting, chatting, and sleeping, and an average of 2.6 hours and 2.2 hours, respectively, on chart review and documentation. In both programs, discussing the case with team members averaged 1.5 hours per night and use of the computer averaged slightly more than half an hour. Internal medicine residents spent approximately 1.5 hours on patients' history and physical examinations while pediatrics residents spent 1.3 hours. With each new patient, internal medicine residents spent an average of 19.7 minutes and pediatrics residents spent 16.5 minutes. The only significant difference between the two groups of residents was that the pediatrics residents spent more time per night on procedures than did the internal medicine residents (37 minutes versus 14 minutes, p < 0.01). CONCLUSIONS: Residents from both programs spent a surprising amount of time each night on chart review and documentation. In fact, they spent more time with charts than with patients. Whether this activity truly contributes to residents' education or improved patients' outcomes is not clear.

Humans↗
PubMed2000

Functioning liver metastases on an I-131 whole-body scan: a case of malignant struma ovarii.

A 46-year-old women was examined for severe constipation. Pelvic examination revealed a large pelvic mass extending to the level of the umbilicus. Computed tomography showed a large multicystic, septated mass in the pelvis and a small amount of fluid in the cul de sac. In addition, multiple ill-defined, mixed-attenuation hepatic lesions were identified. A malignant ovarian neoplasm with liver metastases was considered, so the pelvic mass was resected. Interestingly, histopathologic analysis revealed malignant struma ovarii of the follicular type. Biopsy of the liver lesions confirmed metastatic disease with similar histopathologic findings. All thyroid laboratory values were in the normal range. The patient then had a total thyroidectomy to optimize thyroid ablation therapy with I-131. This revealed a small follicular adenoma but no evidence of cancer. An I-131 whole-body scan was performed and showed uptake in multiple functioning liver metastases.

Adenoma↗