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Biomedical subjects

R Bhatia

Publications and source records attributed to R Bhatia.

At least 109 records · Page 6Linked to original sources
PubMed1995

Serial transcranial Doppler study in meningitis.

Serial transcranial doppler studies were carried out in 12 patients, who developed meningitis during their hospital stay. Blood flow velocities in large basal vessels of the anterior circle of Willis were correlated with CSF pleocytosis and CSF sugar values. Mean blood flow velocities were found to be directly proportional to the CSF white blood cell (WBC) count and were inversely proportional to the CSF sugar values. Blood flow velocities were higher when CSF WBC count was raised. With only one exception these velocities decreased progressively with a fall in the CSF WBC count. At the time of meningitis there occurred a reduction in CSF sugar values and the blood flow velocities were significantly higher. With increase in CSF sugar values there occurred a gradual fall in the blood flow velocities.

Adolescent↗
PubMed1995

Autografting for chronic myelogenous leukemia.

Two thirds of patients with chronic myelogenous leukemia do not have suitable donors for allogeneic transplantation. As for other leukemias, autografting may potentially be curative, because normal Ph- hematopoietic stem cells persist in the marrow and blood of patients with chronic myelogenous leukemia. Several studies indicate that use of unpurged autologous blood or marrow grafts may extend survival for patients undergoing transplantation in chronic phase. Ex vivo or in vivo purging of chronic myelogenous leukemia marrow or blood prior to autografting may result in increased cytogenetic remissions after transplantation in those patients in whom the Ph+ clone can be eliminated. However, when the Ph+ clone cannot be eliminated, use of purged rather than unpurged autografts provides no advantage and may be associated with increased graft failure. Although sustained cytogenetic remissions have not been observed, autografting may result in a plateau in the survival curve not observed with conventional chemotherapy. Efforts are currently directed toward developing improved methods of purging as well as posttransplantation treatments directed against leukemic cells persisting after myeloablative therapy.

Bone Marrow Purging↗
PubMed1995

Treatment of marrow stroma with interferon-alpha restores normal beta 1 integrin-dependent adhesion of chronic myelogenous leukemia hematopoietic progenitors. Role of MIP-1 alpha.

The mechanisms by which interferon-alpha (IFN-alpha) restores normal hematopoiesis in chronic myelogenous leukemia (CML) are not well understood. We have recently demonstrated that IFN-alpha acts directly on CML hematopoietic progenitors to restore their adhesion to marrow stroma by modulating beta 1 integrin receptor function. In the present study we examined the effect of IFN-alpha treatment of marrow stroma on subsequent adhesion of CML progenitors. Stromal layers were preincubated with IFN-alpha (10,000 microns/ml) for 48 h. Subsequent coincubation with CML progenitors for 2 h resulted in significantly increased adhesion of CML progenitors. We demonstrated that alpha 4 beta 1 and alpha 5 beta 1 integrin receptors were involved in the enhanced adhesion of CML progenitors, suggesting that IFN-alpha-treated stroma can upregulate CML integrin function. This effect is due, at least in part, to IFN-alpha-induced increased stromal production of the chemokine macrophage inflammatory protein-1 alpha (MIP-1 alpha), which upregulates beta 1 integrin-dependent adhesion of CML progenitors to stroma. Thus, IFN-alpha treatment of marrow stroma restores beta 1 integrin-dependent adhesion of CML progenitors, at least in part through induction of MIP-1 alpha production. These observations provide further insights into mechanisms by which IFN-alpha may restore normal hematopoiesis in CML.

Adipose Tissue↗
PubMed1995

T lymphocytes cultured from chronic myelogenous leukemia bone marrow suppress autologous hematopoietic progenitors.

In vitro culture of T lymphocytes infiltrating solid tumors has resulted in populations with significant, and sometimes selective, anti-tumor activity. In this study we evaluated the ability of T lymphocyte populations generated from the marrow of patients with chronic myelogenous leukemia (CML) to suppress autologous hematopoietic progenitors. T lymphocyte populations were obtained by culture of CML bone marrow mononuclear cells (BMMNC) with low dose rIL-2 (25 U/ml) after initial PHA stimulation, and restimulation during culture with autologous marrow cells. Preincubation of the cultured CML T lymphocytes in close contact with autologous BMMNC resulted in significant, dose-related suppression of autologous CFU-MIX and BFU-E colonies (P < 0.001). Close contact between effectors and targets was important for progenitor suppression. Progenitor suppression was mediated by CD4-positive T lymphocytes. In contrast to the significant suppression of autologous progenitors by CML T lymphocytes, T lymphocytes from normal bone marrow did not suppress autologous progenitors. We conclude that T lymphocyte populations with significant autologous progenitor suppressing ability can be generated from CML marrow. These observations may be of therapeutic value in CML.

Antigens, CD↗
PubMed1995

Comparison of gastric mucosal blood flow in normal subjects and in patients with portal hypertension using endoscopic laser-Doppler velocimetry.

OBJECTIVE: To compare gastric mucosal blood flow (GMBF) in normal subjects with that in patients with portal hypertension with or without portal hypertensive gastropathy (PHG). METHODS: GMBF was measured by endoscopic laser-Doppler velocimetry in 20 gastroscopically normal subjects and 30 patients with portal hypertension with or without PHG. The effects of breath-holding (vasomotor reflex), submucosal epinephrine and sublingual isosorbide dinitrate were also studied. RESULTS: In normal subjects, GMBF on the greater curvature was (mean +/- SD) 9.5 +/- 1.3 V and on the lesser curvature, 9.1 +/- 1.9 V. Breath-holding caused a reduction in GMBF by 57.1 +/- 13.7%, submucosal epinephrine reduced it by 41.5 +/- 21.5% and sublingual isosorbide caused a rise of 25.8 +/- 15.2%. The GMBF on the greater and lesser curvature respectively in patients with mild PHG (7.7 +/- 1.2 V and 7.7 +/- 0.8 V) and those with severe PHG (6.5 +/- 3.5 V and 6.3 +/- 2.2 V), was significantly less than that in normal subjects (p < 0.05 and p < 0.001 respectively). Vasomotor reflex was blunted in patients with mild and severe PHG (23.3% +/- 20.3 and 23.1% +/- 17.7 respectively, p < 0.001). Responses to submucosal epinephrine and sublingual isosorbide were similar to those recorded in normal subjects. CONCLUSIONS: Patients with portal hypertension have significantly reduced GMBF and significantly attenuated vasomotor reflex in the gastric vascular bed as compared to normal subjects.

Adult↗
PubMed1995

Post-traumatic brain abscess: experience of 36 patients.

Thirty-six patients with post-traumatic brain abscess were managed over 18 years. They constituted 9.3% of all brain abscesses encountered during the same period. The head injury was associated with an external compound fracture in 20, internal compounding in three and was closed in 13 patients. The mean interval between the time of injury to presentation with an abscess was 113 days. This did not differ significantly in patients with closed and compound head injury, and amongst patients who had wound sepsis and with clean wounds after the injury. The occurrence of focal neurological deficit was more frequent in patients with a closed injury (p < 0.05). Twenty patients underwent primary excision of the abscess with recurrence of the abscess in one patient. Of the 14 patients in whom the abscess was initially aspirated, eight patients required a subsequent excision. Excision was required in 18 patients (94.7%) with external compound injury, five (50%) of those with closed injury and in all patients with internally compound injuries. Two patients had 'coned' and died before they could be operated upon. The operative mortality in the absence of signs of herniation preoperatively was 12.5% in patient with compound injury and none among patients with closed head injury.

Brain Abscess↗
PubMed1995

Serodiagnosis of tuberculosis.

To overcome limitations of the conventional laboratory tests for the diagnosis of tuberculosis, attempts have been made in the past to develop a good serodiagnostic test. Until the availability of ELISA results obtained with various immunological techniques were of limited use. Even with ELISA, early attempts to estimate specific antimycobacterial antibodies in the serum were based on the use of crude mycobacterial antigens resulting in a very high false positivity. Better results were obtained with purified antigens. Various purified and semipurified antigens which when used in the ELISA test for estimating antibodies in the serum and other body fluids in cases of tuberculosis have given encouraging results. These include a glycolipid antigen from Myc. bovis BCG (ST = 88%, SP = 96%), antigen '5' (ST = 72%, SP = 91%) and a 38 Kd protein antigen (ST = 83%). Estimation of various mycobacterial antigens in different clinical specimens has also been studied using ELISA technique. Encouraging results have been obtained with the detection of a 43 Kd antigen, Lipoarabinomannan antigen and antigen '5' in the serum, CSF and other body fluids of cases of tuberculosis (ST = 80-100%, SP = 93-100%). The serological tests by detecting specific mycobacterial antigens and antibodies can be of great help in diagnosing the smear negative tuberculosis as these are rapid, inexpensive and simple to perform.

Enzyme-Linked Immunosorbent Assay↗
PubMed1995

Effect of a short course of indomethacin on gastric mucosal blood flow using endoscopic laser-Doppler velocimetry.

OBJECTIVE: To assess the effect of a short course of indomethacin on gastric mucosal blood flow (GMBF). METHODS: Patients with musculo-skeletal pain of recent origin and were prescribed a short course of therapy with indomethacin (25 mg tid for 7 days) were studied Baseline measurements of GMBF were carried out using endoscopic laser-Doppler velocimetry prior to starting indomethacin. At sites on the antrum, incisura, lesser and greater curvatures, and fundus. GMBF measurements were repeated after indomethacin therapy, as above and also on sites of erosions, it any. RESULTS: Baseline GMBF at sites on the antrum, incisura, greater and lesser curvatures, and fundus were (mean) 8.6, 7.9, 8.8, 8.5 and 8.7 volts, respectively. Post-therapy values did not differ from the corresponding baseline values (8.7, 8.5, 8.6, 8.6 and 8.3 volts, respectively). However, ten of the 16 patients developed gastric mucosal erosions and the mean GMBF on these sites of erosion was significantly reduced (6.6 +/- 1.3 volts, p < 0.05). CONCLUSIONS: A short course of indomethacin therapy produces a patchy decrease in blood flow in the gastric mucosa and erosions were seen in these areas.

Adult↗
PubMed1995

Prevalence of toxoplasmosis in Indian women of child bearing age.

A total of 2075 women in child bearing age and with past bad obstetrical history were serologically examined by the indirect immunofluorescence antibody test for Toxoplasma antibodies. 160 (7.72%) serum samples were positive with a titre of 1:64 or more. Maximum prevalence as well as highest titres of antibodies were seen in women aged 36 years and above indicating repeated infections. No association between seropositivity and contact with animals was observed. The low overall prevalence is due to infrequent and uncommon practices of ingesting undercooked or uncooked food especially meat.

Adolescent↗
PubMed1994

Bacteriophage typing in Salmonella bareilly.

A total of 675 strains of Salmonella bareilly received from different parts of India and France during 1959-92 were phage typed using six bacteriophages. Overall typability achieved was 90.8% with 23 distinct phage types excluding a group of untypable strains. Phage types have been defined in octal code. Simpson's coefficient was applied for diversity index having a value of 0.839. This system was found to be reproducible, stable and epidemiologically useful.

Animals↗
PubMed1994

Cushing's disease: pituitary imaging.

Fourteen patients with adrenocorticotropic hormone (ACTH)-dependent hypercortisolism underwent pituitary scanning with computed axial tomography (CT) and magnetic resonance imaging (MRI). Computed tomography revealed pituitary macroadenomas in two patients, pituitary hyperplasia in one and a suspicion of pituitary microadenoma in one. Thirteen patients underwent MRI. One with a macroadenoma diagnosed on CT did not undergo MRI. The MRI revealed a pituitary macroadenoma in one, microadenoma in three and hyperplasia in two cases. Magnetic resonance imaging following gadolinium diethylene triamine penta acetic acid (gd-DTPA) enhancement revealed four more pituitary microadenomas. All patients who had pituitary adenomas (micro and macro) and hyperplasia underwent trans-sphenoidal pituitary surgery. One of the two patients, who had an enlarged pituitary on imaging but no demonstrable adenoma, was found to have a microadenoma at surgery. Patients with ACTH-dependent hypercortisolism should undergo MRI of the pituitary gland to identify/localize corticotroph pituitary adenomas. The study should include gd-DTPA enhancement in cases where the scan is normal.

Adenoma↗
PubMed1994

Interferon-alpha restores normal adhesion of chronic myelogenous leukemia hematopoietic progenitors to bone marrow stroma by correcting impaired beta 1 integrin receptor function.

Treatment of chronic myelogenous leukemia (CML) with interferon-alpha frequently results in normalization of peripheral blood counts and, in up to 20% of patients, reestablishment of normal hematopoiesis. We hypothesize that interferon-alpha may restore normal adhesive interactions between CML progenitors and the bone marrow microenvironment and restore normal growth regulatory effects resulting from these progenitor-stroma interactions. We demonstrate that treatment with interferon-alpha induces a significant, dose-dependent increase in the adhesion of primitive long-term culture initiating cells and committed colony-forming cells (CFC) from CML bone marrow to normal stroma. Adhesion of CFC seen after interferon-alpha treatment could be inhibited by blocking antibodies directed at the alpha 4, alpha 5, and beta 1 integrins and vascular cell adhesion molecule, but not CD44 or intracellular adhesion molecule, suggesting that interferon-alpha induces normalization of progenitor-stroma interactions in CML. Because FACS analysis showed that the level of alpha 4, alpha 5, and beta 1 integrin expression after interferon-alpha treatment is unchanged, this suggests that interferon-alpha may restore normal beta 1 integrin function. Normalization of interactions between CML progenitors and the bone marrow microenvironment may then result in the restoration of normal regulation of CML progenitor proliferation, and explain, at least in part, the therapeutic efficacy of interferon-alpha in CML.

Antigens, CD↗
PubMed1994

Large villous adenoma of the duodenum.

A 27-year-old man, who had symptoms of gastric outlet obstruction, was found on endoscopy to have a large duodenal polyp which on histology was diagnosed as villous adenoma. The tumor was resected surgically and the patient remained asymptomatic until two years later.

Adenoma, Villous↗
PubMed1994

Development of a conjoint phage typing & biotyping schema for Salmonella enterica serovar Senftenberg (S. senftenberg) & the correlation of biotypes with phage types.

A total of 287 strains of S. senftenberg received from various parts of India during 1969 to 1992 were phage typed using six lysogenic phages. The typability was 90.3 per cent and 14 different phage types could be defined excluding a small group of untypable strains. A biotyping scheme was developed utilising six characters and 13 biotypes could be defined. Stern's glycerol medium proved to be the best discriminatory medium. Diversity indeces of phage typing and biotyping schemes were 0.868 and 0.503 respectively. Better discrimination was obtained when phage types were subdivided into different biotypes with a diversity index of 0.931. The schemes were found stable, reproducible and epidemiologically useful.

Bacterial Typing Techniques↗
PubMed1994

Transferable beta lactam resistance against cephalosporins in Salmonella typhimurium strains in India.

From 14 strains of S. typhimurium which were resistant to three cephalosporins (cephalexin, cefadroxil and sodium cefotaxime) the resistance plasmids were transferred to two different strains (Escherichia coli K12F-Lac-Rifr and S. typhimurium LT2). The plasmids were autotransferable and the donors as well as transconjugants showed high levels of MIC (80-320 micrograms/ml or more) against these antimicrobial agents. The resistance was demonstrated to be mediated by a 15 kilobase plasmid.

Cefadroxil↗