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Biomedical subjects

A Kumar

Publications and source records attributed to A Kumar.

At least 199 records · Page 11Linked to original sources

Hypothyroidism alters the expression of Bcl-2 family genes to induce enhanced apoptosis in the developing cerebellum.

Thyroid hormone (TH) deficiency results in delayed proliferation and migration of cerebellar granule cells. Although extensive cell loss during the development of the cerebellum under hypothyroid conditions is known, its nature and its mechanism are poorly understood. Bcl-2 family gene expression is known to determine the fate of cells to undergo apoptosis. We evaluated the effect of hypothyroidism on Bcl-2 family gene expression in the developing rat cerebellum. Electrophoresis and Western blotting were used to analyze DNA fragmentation and expression of DNA fragmentation factor (DFF-45), Bcl-2, Bcl-xL and Bax genes respectively. In the hypothyroid condition, extensive DNA fragmentation and enhanced cleavage of DFF-45 were seen throughout development (postnatal day 0 to day 24) and adulthood whereas they were absent in the euthyroid state. The anti-apoptotic genes Bcl-2 and Bcl-xL were down-regulated and the pro-apoptotic gene Bax was expressed at higher levels compared with the euthyroid state. These results suggest that normal levels of TH prevent cerebellar apoptosis to a large extent, whereas hypothyroidism not only increases the extent but also the duration of apoptosis by down-regulating the anti-apoptotic genes and maintaining a high level of the pro-apoptotic gene Bax.

Animals↗

Biological monitoring of exposure to benzene in traffic policemen of north India.

Occupational health of traffic policemen employed at six major towns of north India was monitored during these investigations. Traffic controllers face the risk of exposure to benzene present in the ambient air as a component of fuel exhaust. Inhaled benzene is metabolized and excreted as phenol. Our observations on urinary phenol show much higher values than prescribed by ACGIH. Furthermore, social habits like alcohol consumption and cigarette smoke were found to modulate benzene metabolism. It was noticed that cigarette smoke synergizes the effect of benzene whereas antagonistic effects of alcohol were observed.

Benzene↗

Pacinian corpuscles hyperplasia--an uncommon cause of digital pain.

The authors present two cases of hyperplasia of Pacinian corpuscles, one in the hand and another in the foot. In the hand the corpuscles were located along the radial border of the pulp of the little finger and presented with localised sharp pain. In the foot, it presented as metatarsalgia in association with Morton's neuroma of the second web space. Both patients underwent exploration and excision of the lesion with complete resolution of symptoms.

Adult↗

Mortality among HIV-infected paediatric patients in Barbados.

Since the onset of the HIV epidemic, AIDS has become the leading cause of mortality in the paediatric age group in many developing countries. The main objective of this study was to review the mortality in HIV-infected paediatric patients in Barbados. It is a retrospective analysis of the hospitalization course of HIV-infected paediatric patients aged < 16 years who died during a 15-year period of surveillance. Using a specific database, information pertaining to number and duration of hospitalizations, and cause of death were analyzed. There were 39 (65%) deaths among 60 HIV-infected patients diagnosed during the period of study. Twenty-one (54%) were male and 18 (46%) were female. Twenty-seven (69%) case records were retrieved for analysis. The highest mortality (56%) was among patients aged < 1 year and between 1989 and 1995. Hospitalizations averaged three per patient. No patient received anti-retroviral therapy. Nineteen (70%) patients died during hospitalization on the paediatric ward. Lower respiratory tract infections suspected to be Pneumocystis carinii, gastroenteritis and septicaemia were the most frequent diagnoses at the time of death. The annual mortality ranged between 0 and 1.7 (mean 0.7) per 1000 live births. The overall mortality rate was high among HIV-infected paediatric patients, with lower respiratory tract infections being implicated as a major contributing cause of death. Results of this study definitely indicate a need for improved resources in the management of paediatric HIV/AIDS cases, especially focussing on the availability and administration of anti-retroviral therapy.

Acquired Immunodeficiency Syndrome↗

Anthropometry and body composition in northern Asian Indian patients with type 2 diabetes: receiver operating characteristics (ROC) curve analysis of body mass index with percentage body fat as standard.

AIMS: To determine the anthropometric profile and appropriate cut off of body mass index (BMI) to define obesity in Asian Indians with Type 2 diabetes mellitus (T2DM). METHODS: Three hundred and eighty T2DM patients (213 males and 167 females) in northern India were subjected to anthropometric and body fat analysis (derived from skinfold thickness). The latter was considered as "standard" for defining obesity. Receiver Operating Characteristics (ROC) curves were drawn for males and females to determine the appropriate limits of BMI to define obesity. RESULTS: Mean values of percentage of body fat (%BF) were 40.2 +/- 6.2% and 29.4 +/- 7.1% in females and males, respectively. Of particular note, substantial percentage of patients had high values of waist-hip ratio (W-HR) [males > 0.95 (53.9%), and females > 0.80 (88.6%)] indicating significant abdominal obesity, and high % BF [males > 25 % BF (73.2%), females > 30% BF (92.2%)] indicating generalized obesity as well. Significantly higher prevalence of obesity was observed in both males (p < 0.001) and females (p < 0.001) when estimated by %BF (males > 25%, females > 30%), as compared to BMI (> 25 kg/m2 in both males and females). ROC curve analysis showed that with %BF taken as the 'standard' for determining obesity, sensitivity and specificity of BMI of > 25 kg/m2 were low. For BMI > 22 kg/m2 in males and > 23 kg/m2 in females, sensitivity increased and there was decrease in overall misclassification. CONCLUSIONS: The data of current study suggest strikingly high prevalence of abdominal obesity, and generalized obesity as determined by %BF in T2DM patients, and that cut offs for defining obesity by BMI are lower than the suggested limit of 25 kg/m2. Revised definition of obesity using lower cut off of BMI, or based on %BF in northern Asian Indian T2DM patients will lead to a more rational application of dietary restriction, lifestyle measures, and use of metformin.

Abdomen↗

Pulmonary hyalinizing granuloma presenting with dysphagia.

We describe a middle aged, non-smoking female who presented with dysphagia and underwent repeated endoscopies and oesophageal dilatation for a period of six months without any response. On imaging she was found to be having a lobulated mass with a radiological differential diagnosis of malignancy, lymphoma or a rare inflammatory lesion. After an inconclusive CT guided biopsy the patient underwent thoracoscopy on which an unresectable mass was found. The biopsy from the mass revealed pulmonary hyalinizing granuloma (PHG). To best of our knowledge this is the first case of PHG presenting as dysphagia reported in the English Literature. Literature on this rare entity is reviewed.

Adult↗

Groundnut as the commonest foreign body of tracheobronchial tree in winter in Northern India. An analysis of fourteen cases.

In Northern India, in an institution like ours which receives quite a number of patients from surrounding rural areas, we found groundnut as the most common foreign body of tracheobronchial tree in children particularly in winter months of October to January. This article attempts to address the potential hazard of groundnut inhalation in children. In Northern India, in an institution like ours which receives quite a number of patients from surrounding rural areas, we found groundnut as the most common foreign body of tracheobronchial tree in children particularly in winter months of October to January. This article attempts to address the potential hazard of groundnut inhalation in children.

Arachis↗

Thyroid function tests in pregnancy.

The recognition of abnormality in thyroid function tests during pregnancy is important for the welfare of the mother as well as fetus. The values of serum tri-iodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH) in nonpregnant women are not applicable during pregnancy and also differ in iodine deficient areas. In the present study, one hundred and twenty-four apparently normal, healthy young primigravidas with no known metabolic disorders and normal carbohydrate gestational intolerance test, consecutively attending the antenatal clinic were included in the study. The serum tri-iodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) in these women were estimated. In the first trimester, the mean T3 values were found to be 1.85 nmol/L, which increased to a mean of 2.47 nmol/L in the second trimester and declined in the third trimester to 1.82 nmo/L. Mean T4 levels were also seen to rise from 164.50 nmol/L in the first trimester to 165.80 nmol/L in the second trimester and then decreased in the third trimester to 159.90 nmol/L. Mean TSH levels were seen to rise progressively through the three trimesters of pregnancy from 1.20 microlU/ ml in the first trimester to 2.12 microlU/ml in the second trimester and further to 3.30 microlU/ml in the third trimester of pregnancy. Three asymptomatic pregnant women (2.5%) were found to have abnormal TSH values with normal T3 and T4 levels and good obstetric outcome. This pilot study also indicates the range to T3 as 1.7 - 4.3 nmol/L in second trimester and 0.4 - 3.9 nmol/L in third trimester, T4 as 92.2 - 252.8 nmol/L in second trimester and 108.2 - 219.0 nmol/ L in third trimester, and TSH as 0.1 - 5.5 microlU/ml in second trimester and 0.5- 7.6 microlU/ml in third trimester of pregnancy.

Adult↗

Modified release bi-layered tablet of melatonin using beta-cyclodextrin.

A modified release bi-layered tablet of melatonin incorporating a fast release fraction consisting of melatonin-beta-cyclodextrin inclusion complex and a slow release fraction containing melatonin in HPMC K15M and Carbopol 971 P matrices was prepared. The formulation developed showed an initial burst followed by a near zero order release pattern for a period of 8 h. The drug content, physical characteristics and the release profile were unaffected after 3 months of an accelerated stability study at 40 degrees C and 75% relative humidity.

Acrylic Resins↗

Relevance of computerized electroencephalographic topography (brain mapping) in ischemic stroke.

BACKGROUND AND AIMS: Computerized electroencephalographic topography (CET) (brain mapping) is a non-invasive, spatially oriented procedure for depicting amplitude and frequency patterns by two-dimensional color-coded frequency and amplitude display of the electroencephalograph (EEG). MATERIAL AND METHODS: We prospectively studied the relationship between CT scan lesions, conventional EEG and brain mapping in 40 patients with ischemic stroke within 1 week of onset. EEG and brain mapping was done within 24 hours of doing CT scan. RESULTS: There were 32 males and 8 females and the mean age was 56 years (range 27-75 years). CET/EEG was normal in 2 patients with capsular infarct. Brain mapping showed abnormalities (most commonly low-frequency high-amplitude changes) in 95% of patients, whereas EEG abnormalities were seen in only 40%. Brain mapping abnormalities were appropriate to the side of the CT scan lesion in 20 (52.63%) patients and were present bilaterally n 18 (47.37%) patients. Brain mapping abnormalities were ipsilateral to the side of the CT lesion when the lesion was < 2 cm in diameter and they were bi-hemispherical when the CT lesion was > 2 cm in diameter. CONCLUSIONS: There was no correlation between motor deficits and brain map abnormalities.

Adult↗

Post-cardiorespiratory arrest beta-alpha coma: an unusual electroencephalographic phenomenon.

The presence of frontally-dominant alpha pattern in the EEG is common in patients with coma due to trauma, toxic-metabolic causes and following cardiorespiratory arrest. Diffuse beta activity following resuscitation after a cardiac arrest is not well recognized. We report a case of coma in a 3-year-old girl who had a cardiac arrest from which she was revived. Initial EEG showed diffuse beta activity, which later evolved to predominantly alpha activity. The possible mechanisms involved in the generation of such rhythms are discussed. Transition of EEG activity from faster to slower frequencies is suggested as an adverse prognostic factor in post-cardiorespiratory arrest coma.

Alpha Rhythm↗

Role of in vivo proton MR spectroscopy in the evaluation of adult brain lesions: our preliminary experience.

CONTEXT: A definite diagnosis and characterization of intracranial mass lesions, based on structural Magnetic Resonance Imaging (MRI) alone may be difficult. In such cases Proton Magnetic Resonance Spectroscopy (1H-MRS) along with other non-invasive techniques represents an advance in the specificity of brain lesion diagnosis. AIMS: The primary aim of this study was to evaluate the extent of the utility of 1H-MRS in adult brain tumors and their differentiation from similar-appearing space-occupying lesions. MATERIAL AND METHODS: MRS studies were performed on 1.5 Tesla whole body MR system using standard imaging head coil. Sixty patients (aged 30-65 years), including 35 males (31-65 years) and 25 females (30-65 years) were studied, along with 25 age-matched healthy volunteers (30-64 years). The Student 't' test was used to statistically analyze the spectroscopic data for significant difference in the metabolite ratios of the lesions from normal brain tissue. RESULTS: The Cho/Cr ratio was significantly raised in low and high-grade glioma and meningioma patients (1.85 +/- 0.36, 3.50 +/- 1.00 and 6.65 +/- 2.83 respectively) (mean +/- standard deviation), as compared with the control group (1.16 +/- 0.18); and NAA/Cr and NAA/Cho ratios were found to be lower than normal values in our study (P<0.01). However, in the non-neoplastic lesions, the Cho/Cr ratios were not statistically significant. The tubercular lesions revealed an average Cho/Cr ratio of 1.24 +/- 0.18, while it was 1.14 +/- 0.07 for infarcts. CONCLUSION: MR Spectroscopy was useful to arrive at a more definitive diagnosis in doubtful intracranial space-occupying lesions with similar morphological imaging patterns.

Adult↗

Phylogenetic relationships between Puerto Rico and continental USA HIV-1 pol sequences: a shared HIV-1 infection.

In order to investigate the existing notion that the human immunodeficiency virus type 1 (HIV-1) infection in Puerto Rico (PR) was imported from the continental United States of America (USA) we sequenced and analyzed 900 bases of the HIV-1 pol sequence from individuals in PR for comparison with pol sequences from the USA mainland. The sequences were derived by direct sequencing of reverse transcription-polymerase chain reaction products generated from plasma virus. The products were sequenced in both directions and the complementary strands were compared prior to analysis. These processed sequences and GenBank sequences from the continental USA were subjected to phylogenetic analyses. The PR and USA sequences did not form independent clusters, indicating a shared HIV-1 infection. This may be due to the continuous human traffic or, less likely, may indicate a similar evolution of a common source virus. Analysis of drug resistance mutations, fairly similar in frequency in the PR and USA sequences analyzed here, supports human traffic as a rationale for the common infection. This work indicates that an efficacious vaccine developed for use in the USA mainland will also be effective in prevention in PR and perhaps the other countries of the Caribbean region.

Drug Resistance, Viral↗