PubMed Health⌕ Search

Biomedical subjects

J Biswas

Publications and source records attributed to J Biswas.

At least 19 recordsLinked to original sources
PubMed2006

Diagnostic value of specific local antibody production and nucleic acid amplification technique-nested polymerase chain reaction (nPCR) in clinically suspected ocular toxoplasmosis.

OBJECTIVE: The study was to evaluate the diagnostic efficacy of nested polymerase chain reaction (nPCR) using primers targeting B1 gene of Toxoplasma gondii (T. gondii) with Witmer Desmonts coefficient (WDC) technique in intraocular fluids of clinically suspected toxoplasma retino choroiditis (TRC) patients. MATERIALS AND METHODS: Two hundred and seventy eight specimens from 189 patients (25 TRC patients and 164 controls) consisting of 189 serum samples and 89 intraocular fluids were included in the study. The clinical specimens were categorized into TRC patients (typical TRC lesion-group I & atypical TRC lesion-group II) and controls (voluntary blood donors-group III, patients undergoing uncomplicated cataract surgery-group IV, ocular inflammation of non-toxoplasma origin-group V). Detection of anti T. gondii IgG and IgM antibodies in serum samples and intraocular fluids were performed and WDC was calculated by the standard method. The standardized nPCR was applied on the 89 intraocular fluids. RESULTS: Clinical diagnosis of TRC based on fundus examination was considered to be the "gold standard." Anti T. gondii IgG/IgM antibodies were detected in serum by ELISA in 95.6% of 25 clinically suspected TRC patients (gp I and II), 28% of gp III, 40.4% of gp IV, and in 58.3% of gpV. Witmer Desmont's coefficient was positive in 72.7% (16/22) and nPCR in 59.1% (13/22) of TRC patients (gp I and II). Both WDC and nPCR were negative in all the controls. The difference in sensitivity of WDC and nPCR was not statistically significant (p=0.5247). CONCLUSIONS: Though both WDC and nPCR were reliable diagnostic techniques for ocular toxoplasmosis, nPCR is more acceptable because of the amount of specimen(s) required, rapidity, cost effectiveness, and direct evidence of T. gondii DNA in the intraocular fluids.

Animals↗
PubMed2004

Thrombosed orbital varix -- a correlation between imaging studies and histopathology.

A thrombosed varix in the orbit is comparatively rare. Clinical examination alone is often inadequate for diagnosis. Radio-logical examination, such as a computed tomography (CT) scan of the orbit, is extremely important. Histopathological examination (HPE) after excision biopsy can confirm the diagnosis. The present authors describe a case of proptosis in the left eye of a 45-year-old man. CT-scan and HPE supported the diagnosis of a thrombosed orbital varix. This paper discusses the use of radiological investigations to supplement a clinical suspicion and make the diagnosis. This entity needs to be included in the differential diagnosis of proptosis and requires a coordinated approach for establishment of the diagnosis.

Biopsy, Needle↗
PubMed2004

Transporter associated protein expression in uveal melanoma.

BACKGROUND/AIM: Transporter associated protein (TAP) is important for presenting peptides to major histocompatibility complex (MHC) class I molecules. Defects in TAP lead to decreased MHC class I expression. The immunoexpression of human leucocyte antigen (HLA) class I molecules and the TAP1 subunit were studied in primary uveal melanomas and correlated with the cell types and extrascleral extension. METHODS: The HLA class I antigen and TAP1 subunit were analysed by immunoperoxidase staining with monoclonal antibodies on 45 primary uveal melanoma archival specimens. The tumours were divided into two groups-group A: tumours with no extrascleral extension; group B tumours with extrascleral extension/liver metastasis. Immunoanalysis was done by a semiquantitative method. RESULTS: HLA class I antigen and TAP1 were decreased in 35 of 35 tumours with no extrascleral extension and positive in six of 10 tumours with liver metastasis. Decreased immunoexpression of HLA class I antigen and TAP1 in uveal melanomas with no extrascleral extension was significant (p<0.001). HLA class I antigen and TAP1 were negative in spindle cell melanomas (p<0.001). CONCLUSIONS: HLA class I antigen and TAP1 expression were decreased in uveal melanomas with no extrascleral extension and in spindle cell melanomas. Decreased expression of TAP1 may lead to decreased expression of HLA class I antigen in uveal melanomas. This preliminary observation deserves further investigation, which may shed more light on the immune escape mechanisms of this tumour and thus enable novel therapeutic strategies.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2004

Current perspectives of herpesviral retinitis and choroiditis.

Vision-threatening viral retinitis are primarily caused by members of the herpesvirus family. The biology and molecular characterization of herpesviruses, clinical presentations of retinopathies, pathology and pathogenesis including the host responses, epidemiology and the laboratory methods of aetiological diagnosis of these diseases are described. Clinical syndromes are acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis, multifocal choroiditis and serpiginous choroiditis besides other viral retinopathies. Herpes simplex virus (HSV) retinitis is more common in immunocompetent persons while varicella zoster virus (VZV) affects both immunocompetent and immunosuppressed patients equally. CMV retinitis is most common among patients with AIDS. The currently employed laboratory methods of antigen detection, virus isolation and antibody detection by enzyme linked immuno-sorbent assay (ELISA) have low sensitivity. Polymerase chain reaction (PCR) has increased the value of diagnosis due to its high clinical sensitivity and absolute specificity in detection of herpesviruses in intraocular specimens.

Choroiditis↗
PubMed2001

Status and distribution of golden langurs (Trachypithecus geei) in Assam, India.

The distribution of golden langurs (Trachypithecus geei) is limited to a small area of western Assam in northeast India and Bhutan between the rivers Manas in the east, Sankosh in the west, and Brahmaputra in the south. It is one of the most seriously endangered primate species of India. A comparative analysis based on satellite images taken in 1988 and 1998 showed a 50% loss of original golden langur habitat. Data on population dynamics collected using line transect and total count methods are presented here. An average group size of 8.2 (range 4.0-22.0) individuals was recorded. A total of 1,064 individuals were counted living in 130 groups. The sex ratio was 1.9-2.5 adult females for each adult male. A low percentage of juveniles and infants suggests that the population is unstable. Most of the groups had only one adult male. Small group sizes, isolated distribution, proportionately few infants and juveniles, and degrading habitat are all causes of concern. Demographic trends indicate a decline in the golden langur population.

Animals↗
PubMed2001

Central retinal vein occlusion due to herpes zoster as the initial presenting sign in a patient with acquired immunodeficiency syndrome (AIDS).

Central retinal vein occlusion (CRVO) due to herpes zoster has rarely been reported. Varicella zoster virus is a common opportunistic infection in patients with AIDS. This case report is about a 40-year-old man with herpes zoster ophthalmicus and central retinal vein occlusion of the right eye who is HIV-positive. Although the lesion resolved following treatment with intravenous acyclovir and oral steroid, the patient subsequently developed florid disc neovascularization and vitreous hemorrhage. The paper highlights CRVO as the initial presentation in an AIDS patient with herpes zoster ophthalmicus.

AIDS-Related Opportunistic Infections↗
PubMed2001

Presumed Eales' disease with neurologic involvement: report of three cases.

PURPOSE: To report three cases of presumed Eales' disease with neurologic lesions. METHODS: Case reports, systemic and neurologic evaluation, and magnetic resonance imaging. RESULTS: All three patients were young men who had seizures in the past; two had migrainous headache. Magnetic resonance imaging showed putaminal infarct in two cases and edema in the white matter of temporal cortex was noticed in one case. Clinical features in all these patients were suggestive of Eales' disease. CONCLUSION: Ischemic infarction of the brain can be seen in clinically suspected cases of Eales' disease.

Adult↗
PubMed2001

Acquired immunodeficiency syndrome and the eye.

This incidence of AIDS is rapidly increasing in the whole world. India is emerging as the country with largest number of AIDS patients. The life time cumulative risk of at least one abnormal ocular lesion developing in an HIV positive ranges from 52% to 100% in various studies. The role of ophthalmologist in the management of an HIV infected patient is becoming increasingly important. This review article describes the common ocular lesions in AIDS patients, particularly seen in Indian patients and available treatment modalities.

AIDS-Related Opportunistic Infections↗
PubMed2001

Boron compounds against human leukemic cells.

Two new boron compoumds, dihydroxy(oxybiguanido) boron (iii) hydrochloride monohydrate (HB) and guanidine biboric acid adduct (GB) were used in this study to observe the antitumor effect. Leukemic blast cells isolated from chronic myeloid leukemia (CML) patients showed significant cell growth inhibition within twentyfour hours. IC50 of GB and HB was 2mg/ml. The metabolically active cells were found to be inhibited by drug treatment as assessed by MTT test. Inhibition of 3H Thymidine incorporation also supported the above result. In this study we investigated the molecular mechanisms by which HB and GB induce apoptosis in immature blast cells.

Apoptosis↗
PubMed2001

Gross photography of ophthalmic pathology specimens.

Removal of the entire eyeball or a portion of it is required in many ophthalmic conditions. The gross features of such specimens provide valuable information. Gross photography of an intraocular tumour, ruptured eyeball or other pathological specimens including lid lesions, orbital tumors, intraocular lens implants, intraocular and extraocular parasites, retinal pathology such as haemorrhages and peripheral degenerations, establishes a permanent documentation. We herein describe the technique of gross photography of such valuable specimens, using a dissecting microscope with a special arrangement. This technique is currently used by us with gratifying results.

Computers↗
PubMed2001

Multiple cranial nerve palsy in an HIV-positive patient.

We report the case of a 32 -year- old HIV-positive Indian male who presented with sixth nerve (bilateral), ninth, tenth and twelfth nerve palsies; cerebellar and posterior column involvement. CT scan showed gyriform enhancement in the right occipital lobe and nodular leptomeningeal enhancement in the left frontal lobe. Cytomegalovirus serology was positive and the patient was treated as presumed CMV. HIV can present with multiple cranial neuropathy and varied neurological involvement.

Adult↗