Biomedical subjects

M Bhalla

Publications and source records attributed to M Bhalla.

At least 19 recordsLinked to original sources

PubMed2000

Odor recognition and identification: effect of labels over time.

The effect of labels on recognition and identification of odors over time was assessed. 30 men and 30 women were presented 20 odors; half of the participants were also told a name for the odor as a label. Five min. and 60 min. later, all participants were given 20 odors (10 from the original set, 10 new) and asked whether each odor was new or old (odor recognition). The group given labels was also asked to recall the label provided (odor identification). Analysis indicated a significant effect of time on recognition. Significantly more odors were recognized at 5 min. than 60 min. The effect of label was also significant, with recognition being better for the Label condition than the No-Label condition. As for odor identification, women identified more labels than did men. Overall, odor recognition was better with labels soon after exposure, and the women were better at remembering the labels than the men.

Adolescent↗

PubMed1999

Visual-motor recalibration in geographical slant perception.

In 4 experiments, it was shown that hills appear steeper to people who are encumbered by wearing a heavy backpack (Experiment 1), are fatigued (Experiment 2), are of low physical fitness (Experiment 3), or are elderly and/or in declining health (Experiment 4). Visually guided actions are unaffected by these manipulations of physiological potential. Although dissociable, the awareness and action systems were also shown to be interconnected. Recalibration of the transformation relating awareness and actions was found to occur over long-term changes in physiological potential (fitness level, age, and health) but not with transitory changes (fatigue and load). Findings are discussed in terms of a time-dependent coordination between the separate systems that control explicit visual awareness and visually guided action.

Adult↗

PubMed1999

Misdiagnosis of toxoplasma infection by PCR: fears unfounded.

A nested PCR based diagnostic assay for the detection of toxoplasmosis was devised in 1990 and was used successfully among a battery of tests for the clinical diagnosis of Toxoplasma gondii infection since 1991. However, it was reported that the assay produced false positive diagnoses with Nocardia asteroides infection. Investigation of this phenomenon showed that although cross reactivity with some unrelated organisms may be observed when altered conditions are employed, the assay does not lead to misdiagnosis if performed under the appropriate, stringent conditions.

Actinomyces↗

PubMed1998

Anti-inflammatory benzopyran-2-ones and their active oxygen species (aos) scavenging activity.

Benzopyrano derivatives were synthesized and evaluated for their anti-inflammatory, ulcerogenic activities and toxicity studies. The in-vitro studies comprised of anti-proteolytic activity, lipid peroxidation inhibitory and reducing activities against alpha, alpha-diphenyl-beta-picrylhydrazyl (DPPH). Two potent compounds were studied further for their inhibition of lipid peroxidation and effect on Superoxide dismutase (SOD) activity in-vivo. These compounds were found promising in all the parameters studied, thereby signifying inter-relationship between their anti-inflammatory activity and anti-oxidant properties.

Animals↗

PubMed1997

Volumetric (helical/spiral) CT (VCT) of the airways.

Volumetric computed tomography (VCT) represents an important improvement over conventional CT for assessing most airway abnormalities. Elimination of misregistration due to variations in respiration coupled with decreased motion artifact and the ability to obtain routine overlapping sections allow a more confident estimation of the presence and extent of disease. Recently, attention has focused on newer reconstruction techniques including: multiplanar reconstructions (MPRs), including curved multiplanar reformations; multiplanar volume reconstructions (MPVRs) using ray projection techniques, such as maximum and minimum projection imaging; external rendering, or 3D-shaded surface displays; and, most recently, internal rendering or so-called "virtual bronchoscopy". Given the often redundant nature of many of these methodologies determining indications for their use remains to be established, especially by comparison to axial imaging. The purpose of this article is to review these various reconstruction techniques and, based on current knowledge, place them in an appropriate clinical context.

Humans↗

PubMed1997

AIDS-related airway disease.

To our knowledge, the importance of airway disease in HIV-positive patients has been infrequently noted. This deficit likely reflects a combination of factors including lack of familiarity with recent changes in clinical and epidemiologic patterns of pulmonary manifestations of HIV infection and documented limitations of chest radiography for identifying and differentiating airway disease from other causes of pulmonary disease in HIV-positive patients. Familiarity with the imaging findings for these various entities should facilitate prompt diagnosis and treatment. The accuracy of CT in detecting airway disease [55-59] is well established and should be of value in excluding more common diseases that may be initially confused with airway abnormalities [60, 61]. Small airways disease, in particular, which may be occult or mimic an interstitial infiltrate on chest radiography, can be recognized with CT as likely representing infectious bronchitis or bronchiolitis. Patients with findings suggesting bacterial infections may benefit from empiric antibiotic therapy. CT also may be valuable for differentiating between various noninfectious pulmonary diseases, allowing a presumptive diagnosis of parenchymal Kaposi's sarcoma in the appropriate clinical context. In distinction, by detecting localized endobronchial or parenchymal abnormalities in patients with mycobacterial or fungal infections or lymphoma, CT may be valuable for deciding between various invasive methods of obtaining either histologic or bacteriologic diagnoses.

AIDS-Related Opportunistic Infections↗

PubMed1997

Inherited factor X deficiency in two brothers.

Two brothers born to same parents were diagnosed with inherited factor X deficiency of severe type. Clinical presentation in both the cases were haemarthrosis. The elder brother was diagnosed in the year 1991 when he was four and half years old. Recently the youngest child in the family also presented with haemarthrosis at age of one and half years. Diagnosis was made by abnormal results of Coagulation factors screening mainly Prothrombin time, Activated partial thromboplastin time, Russell's viper venom test, mixing tests factor X assay. Both the brothers had Factor X activity less than one percent.

Child, Preschool↗

PubMed1996

Diffuse lung disease: assessment with helical CT--preliminary observations of the role of maximum and minimum intensity projection images.

PURPOSE: To evaluate assessment of diffuse lung disease with helical computed tomography (CT) and maximum intensity projection (MIP) and minimum intensity projection images. MATERIALS AND METHODS: Six patients with suspected lung disease (the control group) and 20 patients with documented disease underwent axial helical CT through the upper and lower lung fields. Findings on the MIP and minimum intensity projection images of each helical data set were compared with findings on the thin-section scan obtained at the midplane of the series. RESULTS: Owing to markedly improved visualization of peripheral pulmonary vessels (n = 26) and improved spatial orientation, MIP images were superior to helical scans to help identify pulmonary nodules and characterize them as peribronchovascular (n = 2) or centrilobular (n = 7). Minimum intensity projection images were more accurate than thin-section scans to help identify lumina of central airways (n = 23) and define abnormal low (n = 15) and high (ground-glass) (n = 8) lung attenuation. Conventional thin-section scans depicted fine linear structures more clearly than either MIP or minimum intensity projection images, including the walls of peripheral, dilated airways (n = 3) and interlobular septa (n = 3). MIP and minimum intensity projection images added additional diagnostic findings to those on thin-section scans in 13 (65%) of 20 cases. CONCLUSION: MIP and minimum intensity projection images of helical data sets may help diagnosis of a wide spectrum of diffuse lung diseases.

Adult↗

PubMed1996

Noncardiac thoracic surgical procedures. Definitions, indications, and postoperative radiology.

The radiologist should be familiar with the various operative procedures of the chest to accurately interpret routine postoperative radiologic studies. This also will assist them in the detection of common iatrogenic problems and postoperative complications such as bleeding, air leak, and infection. Furthermore, knowledge of serious and specific complications such as cardiac herniation and post-pneumonectomy syndrome can help the radiologist play an active role in the postoperative care of such patients.

Esophagus↗

PubMed1995

Unusual lymphoproliferative disorders in nine adults with HIV or AIDS: CT and pathologic findings.

PURPOSE: To identify characteristic computed tomographic (CT) findings in unusual pulmonary lymphoproliferative disorders seen in adults with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: The authors retrospectively reviewed the CT scans and pathologic specimens from nine patients with pulmonary lymphoproliferative disorders. CT scans were evaluated for nodules, reticulation, areas of ground-glass attenuation, consolidation, and bronchial disease. Changes seen in pathologic specimens were classified as consistent with classic lymphocytic interstitial pneumonitis (LIP), mucosa-associated lymphoid tissue lymphoma (MALTOMA), or atypical lymphoproliferative disorder (ALD). Immunopathologic results were reviewed when available. RESULTS: Eight patients had AIDS. Five patients had classic LIP. One patient had MALTOMA, and three patients had ALD. Altogether, 2-4-mm-diameter nodules were the predominant CT finding in eight patients; these were peribronchovascular in four patients. The presence of interstitial nodules correlated with the pathologic finding of nodular disease in seven patients. CONCLUSION: Familiarity with these AIDS-related disorders and their CT appearance should assist in the differential diagnosis.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Synthesis and pharmacological evaluation of 1,2,4-triazine and its congeners.

3-[Mercapto]-n-propanoxy/methyl-ethanoxy branched chain in 5,6-Diphenyl- 1,2,4-triazine were condensed with O-phenylene diamine or O- aminophenol or o-aminothiophenol. The carboxylic groups of the synthesized compounds were cyclised to yield imidazoles, oxazoles and thiazoles. They were screened for their anti-inflammatory response in albino rats against carrageenin induced paw oedema. The active compounds were also evaluated for their ED50 value in albino rats and analgesic activity in albino mice. The compounds exhibited significant anti-inflammatory activity also showed marked protection against aconitine induced writhing response. The potent compounds showed high LD50 values.

Animals↗

PubMed1995

Substituted quinazolinones and their anti-inflammatory activity.

6-Substituted-2-alkyl-3-(4-aminobenzene sulphonamido)quinazolin-4-(3H) ones (1a-b) were converted either to 2-methyl 3-[(N-aminoacylbenzoate)benzenes sulphonamido]quinazolin-4 (3H) ones (2a-c) or to 6-substituted-2-alkyl-3-(N-arylidene benzene sulphonamido)-quinazolin-4- (3H) ones (3a-h). 3 on reduction, yielded 6-substituted-2-alkyl-3-(N-arylmethyl sulphonamido)-quinazolin-4(3H)ones (4a-l). Reaction of 3a-h with thioglycolic acid afforded 2-alkyl-3-[4'-(5'-arylthiazolidin-3'-one)benzene sulphonamido]quinazolin-4(3H)ones (5a-h). All these compounds were evaluated for their anti-inflammatory activity against carrageenin induced rat's paw oedema. Active compounds were also evaluated for ulcerogenic liability and ALD50 values.

Animals↗

PubMed1994

Surgical flaps in the chest: anatomic considerations, applications, and radiologic appearance.

PURPOSE: To determine the frequency of use of surgical flaps--tissue that is transposed from its normal location to promote healing and prevent complications--in noncardiac thoracic surgery and to demonstrate the typical radiologic appearances of such flaps. MATERIALS AND METHODS: The surgical records of 200 patients who underwent thoracotomy or median sternotomy for noncardiac thoracic surgery were reviewed. Postoperative radiologic studies of randomly selected cases were also reviewed. RESULTS: A total of 213 surgical flaps were used in these patients, including 80 pericardial fat pad flaps (37.6%), 78 greater omental flaps (36.6%), 21 intercostal muscle flaps (9.9%), 16 anterior serratus muscle flaps (7.5%), and 18 greater pectoral muscle, latissimus dorsi muscle, pleural, thymic, or mediastinal fat flaps (8.5%). The flaps produced unusual opacity or attenuation and/or contour of the mediastinum, hilum, or chest wall. CONCLUSION: Knowledge of common thoracic surgical flaps is helpful in interpretation of postoperative radiologic studies.

Adipose Tissue↗

PubMed1994

Needle localization of peripheral lung nodules for video-assisted thoracoscopic surgery.

Video-assisted thoracoscopic surgery provides an alternative to conventional thoracotomy for resection of peripheral lung nodules. To localize small peripheral lung nodules that may not be visible or palpable by the surgeon, we have placed a Kopans hook wire percutaneously into the lung as a guide. The indications for localization included previous nondiagnostic percutaneous needle aspiration biopsy (PNAB) (n = 4), nodules too small for PNAB (n = 2), nodules inaccessible to PNAB (n = 3), and planned resection of a known peripheral tumor less than 1 cm (n = 1). The localization procedure was performed with computed tomographic guidance in all patients. The nodules ranged in size from 2 to 15 mm and were located immediately subpleural to 2-cm deep the pleura. A 20-gauge Greene biopsy needle was used as an introducer for a 35-cm-long Kopans hook wire. Patients were sent directly to the operating room in a dependent position. All ten nodules were successfully resected, including hamartoma (n = 1), carcinoid tumors (n = 2), granulomas (n = 3), adenocarcinoma (n = 1), fibrosis (n = 1), benign metastasizing leiomyoma (n = 1), and lymphoma (n = 1). In two patients, the wire slipped out of the lung. Small focal pneumothoraces developed in five patients. There were no major complications. This procedure can safely and effectively localize nonvisible or nonpalpable pulmonary nodules for thoracoscopic surgery for diagnostic purposes or for resection of small peripheral tumors in patients who cannot tolerate a lobectomy or pneumonectomy.

Aged↗

PubMed1994

Adenosquamous carcinoma of the lung: radiologic appearance.

OBJECTIVE: To our knowledge, the imaging features of pulmonary adenosquamous carcinoma, a form of bronchogenic carcinoma with a greater propensity for metastases at the time of diagnosis and a poorer prognosis than other forms of bronchogenic carcinoma, have not been reported. Accordingly, we studied the radiologic appearance of this tumor to describe the findings and discern if there are features that distinguish it from other bronchogenic carcinomas. MATERIALS AND METHODS: Clinical and radiologic features of 30 cases of adenosquamous carcinoma were reviewed. Chest radiographs were available in all cases and CT scans were available in 23. In cases without CT scans, planar tomograms were reviewed in five cases and MR images were reviewed in one. Tumors were defined by location, morphology, and TNM classification. RESULTS: The tumors measured 0.6-6.5 cm in diameter (mean, 2.8 cm) on CT scans or chest radiographs. One tumor not seen even in retrospect on CT scans or chest radiographs was found at autopsy. Twenty-five tumors were solid and four were cavitary. Five tumors were central and 25 were peripheral, including one tumor of the superior sulcus of the lung and the tumor not seen at imaging. Tumor margins were poorly defined in 19 and spiculated in 10. Four large masses had heterogeneous attenuation on CT scans; one had punctate calcification. Fifty-three percent of tumors were peripheral nodules 1-3 cm in diameter. Results of fine-needle aspiration of 18 masses indicated malignant tumors in 16 cases, but adenosquamous carcinoma in only two. Evidence of previous lung injury, including tumor in or next to scar, pneumoconiosis, radiation fibrosis, and interstitial fibrosis, was found on CT scans, chest radiographs, and/or pathology in half the patients. CONCLUSION: The radiologic findings of adenosquamous lung carcinoma are a spectrum, typically a peripheral solitary nodule, less commonly a central hilar mass or tumor of the superior sulcus. Scar or fibrosis within the lungs suggests that adenosquamous carcinoma, just as adenocarcinoma, may arise in scarred lung parenchyma.

Aged↗

PubMed1994

Synthesis of 1,3,4-thiadiazole-[3,2,-a]-s-triazine-5,7-dithione derivatives and their pharmacological evaluation.

2-Mercapto-6-phenyl-1,3,4-thiadiazole-(3,2-a)-s-triazine-5,7-dithione (1) was converted to 2-[3-carboxyl-2-methyl-1-mercapto]-6-phenyl-1,3,4-thiadiazole-(3,2-a)-s- triazine-5,6 dithione (2) and 2-thioethanoic acid-6-phenyl-1,3,4-thiadiazole-(3, 2-a)-s-triazine-5,7-dithione (4). This on reaction with o-phenylenediamine/ethylenediamine/o-aminophenol/o-aminothiophenol and polyphosphoric acid yielded compounds 3 (a-d) and 5 (a-d). The compounds 1,2,4,3 (a-d) and 5 (a-d) were evaluated for their anti-inflammatory activity against carrageenan induced paw oedema. The compounds found potent were further tested for their antiwrithmogenic activity in albino mice. Two compounds (2,3c) exhibited significant anti-inflammatory activity, also showed protection against aconitine induced writhing response, with high approximate LD50 values.

Animals↗

PubMed1994

Modified Levinson's test in rapid diagnosis of tuberculous meningitis.

Modified Levinson's precipitation test was done in 64 cases of TBM, 54 cases of TBM with inconsistent CSF finding, and 32 cases of pyogenic meningitis. The test was positive in 93.7% cases of TBM (sensitivity, 93.7%), 85.5% cases of TBM with doubtful diagnosis and in 9.4% cases of pyogenic meningitis (specificity 90.6%) compared to 79.7%, 72.2% and 18.8% in original Levinson's test, respectively. With CSF examination only 66% cases of TBM could be diagnosed while with modified Levinson's test and CSF analysis 89% cases could be diagnosed (p < 0.001). So modified Levinson's test for diagnosis of TBM is better than Levinson's test (p < 0.05) with an added advantage of time saving.

Antitubercular Agents↗

PubMed1994

Radiographic features useful for establishing patient identity from improperly labeled portable chest radiographs.

Radiologists in hospital practice often encounter radiographs that either bear no patient identification or are incorrectly labeled as those of a different patient. To avoid repeating these improperly labeled radiographs, and to establish correct patient identity, most radiologists compare these radiographs with previous radiographs of several patients. This happens most often with portable chest radiographs. To study the reliability of various surgical, pathologic, and anatomic features and to help establish a fast and accurate method of establishing the correct patient identity, we performed a retrospective study of 50 patients in the intensive care unit. The characteristic location and configuration of surgical material, fractures, and dense parenchymal/pleural scars with or without calcifications are extremely helpful in establishing patient identity. In the vast majority of patients who lack such characteristic surgical and pathologic features, the anatomic structures that are most reliable for identification purposes are, in order of decreasing reliability, the transverse processes of the first thoracic vertebrae and the adjoining tubercles of the first ribs, the spinous processes, and the scapular wings. We believe that this information will help radiologists to identify the right patient when radiographs are incorrectly labeled.

Adult↗