Biomedical subjects

A Haque

Publications and source records attributed to A Haque.

At least 37 records · Page 2Linked to original sources

PubMed2001

Heparin-binding EGF-like growth factor decreases inducible nitric oxide synthase and nitric oxide production after intestinal ischemia/reperfusion injury.

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) has been shown to protect intestine from ischemia/reperfusion (I/R) injury in vivo and to down-regulate inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in intestinal epithelial cells in vitro. The present study was undertaken to investigate whether HB-EGF could modulate the iNOS/NO axis after total midgut I/R injury in rats. I/R injury induced a significant increase in iNOS gene expression (quantified by real-time RT-PCR) and protein production (detected by western blots), as well as elevation of serum NO levels (measured by chemiluminescence assay). Nitrotyrosine (NT) and iNOS production colocalized immunohistochemically, with positive staining found mainly in villous and crypt epithelial cells, as well as ganglion cells. Intraluminal administration of HB-EGF 45 min after the start of a 90-min ischemic interval significantly decreased I/R-induced iNOS gene expression and protein production, as well as serum NO levels. Immunohistochemically, HB-EGF administration led to elimination of iNOS and NT staining in crypt epithelial cells and ganglion cells, with only weak staining that remained in villous epithelial cells. Thus, HB-EGF protects the intestine from I/R injury, at least partially, through down-regulation of the iNOS/NO/NT pathway, a mechanism that is central to I/R injury in multiple organ systems.

Animals↗

PubMed2001

Apolipoprotein E genetic polymorphism and stroke subtypes in a Bangladeshi hospital-based study.

The association between apolipoprotein E (apoE) genetic polymorphism and stroke has not been concordant in different racial populations. We investigated the association between apoE genotypes and stroke subtypes by a case-control study in Bangladesh for the first time among south Asian countries. First-ever-stroke patients (n=227; cerebral infarction, n=147, cerebral hemorrhage, n=80) and 190 controls were recruited from a hospital in Dhaka, Bangladesh. The diagnosis of stroke was based on CT and clinical findings. Cerebral infarction was classified anatomically into cortical and penetrating region. Infarction in the cortical region was further categorized etiologically into thrombosis and embolism. Cerebral hemorrhage was considered as a whole in all analyses. ApoE genotypes were determined by restriction fragment length polymorphism. In the multivariate conditional logistic regression analysis adjusted for potential confounders both the epsilon3/epsilon4 genotype and epsilon4 carrier conferred an approximately 3-fold increased risk for cerebral thrombosis in the cortical artery region (OR 3.5, 95% CI 1.2 to 10.4 and OR 3.1, 95% Cl 1.1 to 9.0, respectively) compared with epsilon3/epsilon3 genotype. However, when the analysis was restricted to the elderly (>60 years), epsilon 2 carrier was associated with a risk of hemorrhagic stroke (OR 19.2, 95% CI 1.3 to 295.2). Our study suggested that both apoE epsilon3/epsilon4 genotype and epsilon4 carriers were risk factors for cerebral thrombosis in cortical artery region, whereas epsilon 2 carrier was a risk factor for hemorrhagic stroke in the elderly.

Aged↗

PubMed2001

Computed tomographic-pathologic correlation of gross tumor volume and clinical target volume in non-small cell lung cancer: a pilot experience.

CONTEXT: Computed tomographic (CT) scan data are used regularly in radiation treatment planning for patients with lung cancer. To our knowledge, the relationship of the CT images of tumors and their corresponding microscopic extent has not yet been studied in detail. OBJECTIVE: To correlate tumor sizes on CT with tumor sizes measured microscopically (ie, the gross tumor volume [GTV]-clinical target volume margin) in non-small cell lung cancers. DESIGN: Prospective pilot study. SETTING: Single institution. PATIENTS: Patients with operable non-small cell lung cancer were identified preoperatively. INTERVENTIONS: Once the surgical specimen was available, it was oriented with the surgeon and the pathologist. Seven whole-mount, cross-sectional histologic glass slides were made from 5 tumors using formalin fixation and hematoxylin-eosin staining. The pathologist then outlined the cancer-containing area under the microscope (Micro-GTV) and the area of surrounding inflammatory response (Micro-GTV + inflammation). Preoperative CT scans were used for outlining tumor on the corresponding slice (CT-GTV). MAIN OUTCOME MEASURES: Correlation of the areas of Micro-GTV, Micro-GTV + inflammation, and CT-GTV was performed. RESULTS: There was an obvious trend that the CT-GTV was bigger than the Micro-GTV, except in specimen 1, in which the 2 areas were about equal. However, on comparing the values for the CT-GTV and the Micro-GTV + inflammation, the difference between the 2 areas became smaller. CONCLUSIONS: Modern CT scans might overestimate the GTV in non-small cell lung cancer. The GTV-clinical target volume margin could actually be zero or even a negative value. The findings in this small study are interesting and provoking. Further study with a larger number of patients and more rigid quality control is warranted to confirm our findings.

Carcinoma, Non-Small-Cell Lung↗

PubMed2001

Prednisolone in Duchenne muscular dystrophy.

This Study was carried out in the department of Neuromedicine, Bangabandbu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh. A total of 19 Duchenne muscular dystrophy (DMD) patients were recruited for randomized controlled study to see the effect of prednisolone in the natural course of the disease process. Prednisolone was given in 10 patients (study group) in a dose of 0.75 mg/kg for six months. Vitamin was given in 8 patients (control group) for the same duration. One patient was dropped from the study. Patients were assessed for average muscle strength, timed function test and functional grades (pelvic and pectoral). It was found that at the end of the study, almost all the parameters were improved significantly in the prednisolone treated group (P < 0.05).

Activities of Daily Living↗

PubMed2001

Utility of PCR in diagnosis of problematic cases of typhoid.

Typhoid is a global problem. Conventional diagnostic methods have limitations. The Widal test gives a high proportion of false positive results, and indiscriminate use of antibiotics has reduced the utility of blood culture. Consequently, these procedures are inadequate for diagnosing suspected cases of typhoid that do not present clear-cut symptoms. We previously showed that PCR-based diagnosis of typhoid targeting the flagellin gene has unparalleled specificity. We assessed the utility of this method for diagnosis of problematic cases of typhoid. A comparative study of PCR, blood culture, and Widal test was carried out on 55 cases of suspected typhoid with fever for 3-30 days and possessing an ambiguous clinical picture. A control group comprised of 20 healthy persons was also included. The respective positive results by PCR, blood culture, and Widal test for these groups were 58.2 and 0%, 14.5 and 0%, and 52.7 and 45%. Sensitivity of PCR as compared with that of blood culture was significantly better. We concluded that PCR is much superior to conventional methods and, due to its high sensitivity and specificity, can be of great use for rapid and definitive diagnosis of problematic cases of typhoid.

Case-Control Studies↗

PubMed2001

Stroke: seasonal variation and association with hypertension.

A prospective study was contemplated with 155 patients of acute stroke in the Department of Neurology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, from March 1996 to February 1997. The objective of the study was to find out seasonal variation of stroke occurrence. An attempt was also made to find out the association of hypertension with ischaemic and haemorrhagic stroke during summer and winter. The numberofsubjects duringsummer and winterwere 121 and 34, respectively. In summer, out of 121 subjects, 87(71.9%) were ischaemic stroke and 34(28.1%) haemorrhagic stroke, of which 32 were intracerebral haemorrhage (ICH) and 2 subarachnoid haemorrhage (SAH). There were 18 (52.9%) ischaemic stroke and 16(47.06%) haemorrhagic stroke (all ICH) among total 34 subjects during winter. The frequency of ischaemic stroke during summer was significantly greater than that during winter (p<0.05). The frequency of haemorrhagic stroke during winter was significantly greater than that during summer (p<0.05). Temperature was positively correlated to ischaemic stroke (p<0.01) and negatively correlated to haemorrhagic stroke (p<0.1). Hypertension was significantly more associated with haemorrhagic stroke than with ischaemic stroke irrespective of season (p<0.05).

Adult↗

PubMed2001

Depression after stroke-analysis of 297 stroke patients.

Stroke is commonly followed by some form of psychiatric disturbance. Association and severity of depression at the 3rd and 12th months after stroke in patients and controls were compared. Two registers of stroke patients were maintained over 2 years period in two different centers--one in Barisal Town and other in Mitford Hospital, Dhaka. A total of 297 first-ever strokes were registered. These patients were called back at the 3rd and 12th month interview and assessment. Beck's Depression Inventory (BDI), with 10 as the cut off point for depression, was applied to 161 of 212 survivors at the 3rd month and to 156 of 195 survivors at the 12th month. At the 3rd month, 41% of patients and 18% of controls were depressed (P<.001) and the difference was maintained at the 12th month 42% versus 19% (P<.05). Univariate risk factors for depression at the 3rd month were female sex, severe prognostic score at the onset of stroke, age more than 70 years, family history of stroke and living alone after stroke. Depression was common among stroke survivors at the 3rd months and its rate did not decrease at 1 year follow-up. Depression could be decreased if post-stroke rehabilitation services are improved. After the development of depression earlier diagnosis and management help a lot to the patients and care givers.

Aged↗

PubMed2000

Use of the stationary phase inducible promoters, spv and dps, to drive heterologous antigen expression in Salmonella vaccine strains.

We have investigated the ability of the growth phase regulated promoters dps and spv, to drive expression of heterologous antigens in Salmonella vaccine strains. Reporter plasmids were constructed which directed beta-galactosidase expression from dps (pDpslacZ) or spv (pSpvlacZ) and these were introduced independently into the Salmonella typhimurium vaccine strain SL3261 (aroA(-)). beta-galactosidase expression was induced 20-fold and 100-fold when broth cultures of SL3261 (pDpslacZ) or SL3261 (pSpvlacZ) respectively, entered the stationary phase of growth. Within macrophages, beta-galactosidase expression was induced 3.5-fold with SL3261 (pDpslacZ) and 7-fold with SL3261 (pSpvlacZ). The spv and dps promoters were used to drive independent expression of the C fragment domain of tetanus toxin (TetC) from plasmids harboured in S. typhimurium SL3261. Levels of anti-TetC antibodies were significantly higher in the sera of BALB/c mice perorally inoculated with SL3261 (pSpvtetC) or SL3261 (pDpstetC) compared to unvaccinated controls. This suggests that these promoter systems may be used to drive foreign antigen expression in live oral Salmonella vaccines.

Animals↗

PubMed2000

Socioeconomic distress and health status: the urban-rural dichotomy of services utilization for people with sickle cell disorder in North Carolina.

Research on sickle cell disorder has not focused attention on the socioeconomic background and geographic distribution of people with the disease. This study examines 1,189 persons with sickle cell disorder in North Carolina during 1991 to 1995. Three indices were developed using clients' medical, psychosocial and socioeconomic characteristics for the purpose of analyzing the urban-rural difference in treatment for sickle cell disease. The study observed a wide disparity in these indices between urban and rural population groups. Also, differences were observed in the utilization of services and clients' health status. The findings suggest that utilization of services is directly related to socioeconomic condition facing clients and clinic distance from clients. They further suggest that people in rural areas who have high distress levels and are far from clinics have limited access to health care. The limited availability of medical and health care in rural areas, as well as other support systems calls for an increase in community based healthcare services. These findings should be of particular interest to the state level sickle cell disorder program in North Carolina and other areas with a large rural population. Enhanced support for all persons with sickle cell disorder in North Carolina, particularly those in rural areas, is critical.

Adolescent↗

PubMed2000

Cardiovascular and other risk factors for Alzheimer's disease and vascular dementia.

Factors accelerating cerebral degenerative changes represent potentially modifiable risks for cognitive decline. Putative risks accelerating subtle cognitive decline and dementia were correlated with repeated measures of cerebral atrophy, CT densitometry, perfusions, and cognitive testing among 224 neurologically and cognitively normative aging volunteers. After age 60, cerebral atrophy, ventricular enlargement, polioaraiosis, and leukoaraiosis geometrically increased as perfusions declined. Risks accelerating perfusional decline, cerebral atrophy, polioaraiosis, and leukoaraiosis were: transient ischemic attacks (TIAs), hypertension, smoking, hyperlipidemia, male gender. At age 71.5 +/- 11.9, subtle cognitive decline began, accelerated by TIAs, hypertension, and heart disease. Leukoaraiosis began before cognitive decline. TIAs, hypertension, and hyperlipidemia correlated with vascular dementias. Excessive cortical perfusional decreases and cerebral atrophy correlated with cognitive decline. Family history of neurodegenerative disease correlated with Alzheimer's disease. We concluded that TIAs, hypertension, hyperlipidemia, smoking, and male gender accelerate cerebral degenerative changes, cognitive decline, and dementia.

Adult↗

PubMed2000

Baroreflexes prevent neurally induced sodium retention in angiotensin hypertension.

Recent studies indicate that renal sympathetic nerve activity is chronically suppressed during ANG II hypertension. To determine whether cardiopulmonary reflexes and/or arterial baroreflexes mediate this chronic renal sympathoinhibition, experiments were conducted in conscious dogs subjected to unilateral renal denervation and surgical division of the urinary bladder into hemibladders to allow separate 24-h urine collection from denervated (Den) and innervated (Inn) kidneys. Dogs were studied 1) intact, 2) after thoracic vagal stripping to eliminate afferents from cardiopulmonary and aortic receptors [cardiopulmonary denervation (CPD)], and 3) after subsequent denervation of the carotid sinuses to achieve CPD plus complete sinoaortic denervation (CPD + SAD). After control measurements, ANG II was infused for 5 days at a rate of 5 ng. kg(-1). min(-1). In the intact state, 24-h control values for mean arterial pressure (MAP) and the ratio for urinary sodium excretion from Den and Inn kidneys (Den/Inn) were 98 +/- 4 mmHg and 1.04 +/- 0.04, respectively. ANG II caused sodium retention and a sustained increase in MAP of 30-35 mmHg. Throughout ANG II infusion, there was a greater rate of sodium excretion from Inn vs. Den kidneys (day 5 Den/Inn sodium = 0.51 +/- 0.05), indicating chronic suppression of renal sympathetic nerve activity. CPD and CPD + SAD had little or no influence on baseline values for either MAP or the Den/Inn sodium, nor did they alter the severity of ANG II hypertension. However, CPD totally abolished the fall in the Den/Inn sodium in response to ANG II. Furthermore, after CPD + SAD, there was a lower, rather than a higher, rate of sodium excretion from Inn vs. Den kidneys during ANG II infusion (day 5 Den/Inn sodium = 2.02 +/- 0.14). These data suggest that cardiac and/or arterial baroreflexes chronically inhibit renal sympathetic nerve activity during ANG II hypertension and that in the absence of these reflexes, ANG II has sustained renal sympathoexcitatory effects.

Angiotensin II↗

PubMed2000

XE-CT CBF changes during normative aging, cognitive decline and dementia.

Factors accelerating cerebral degenerative changes represent potentially modifiable risks for cognitive decline. Putative risk factors accelerating mild cognitive decline and dementia were correlated with repeated measures of cerebral atrophy, CT densitometry, perfusions and cognitive testing among neurologically and cognitively normative volunteers. TIAs, hypertension, smoking and male gender accelerate cerebral degenerative changes, mild cognitive decline and dementia. Intervention by control of risk factors and cholinesterase inhibitors should prevent cerebral atropho-degenerative changes so that optimal cognitive performance is maintained.

Adult↗

PubMed1999

Immunization with heat-killed Toxoplasma gondii stimulates an early IFN-gamma response and induces protection against virulent murine malaria.

In this study, we describe protection of BALB/c mice by immunization with heat-killed T. gondii tachyzoites against infection with Plasmodium yoelii 17XL which causes cerebral malaria and death in mice by day 7-8 post infection. Immunization resulted significant reduction in parasitemia at the peak period of infection. Protection induced by heat-killed T. gondii was associated with marked increase in NK cell number and IFN-gamma mRNA expression early in the infection. The level of IFN-gamma or TNF-alpha was found to diminish in T. gondii-treated mice as the infection progressed to the late stage. This declined response of IFN-gamma or TNF-alpha was associated with marked increase in the expression of IL-10, a counterregulatory cytokine. Pretreatment of mice with live T. gondii induced poor level of protection as compared with that of heat-killed parasites. Mice that received P. yoelii infection alone, had an elevated IFN-gamma response in the late stage of infection. Development of cerebral malaria in untreated mice was accompanied by an augmented production of TNF-alpha and nitric oxide (NO), the proinflammatory mediators. These findings suggest that nonspecific immunization with T. gondii leads to restoration of an early IFN-gamma response in P. yoelii-infected mice and in the establishment of an immunoregulatory mechanism that effectively antagonizes the disease-promoting effects of proinflammatory cytokines in the late phase of infection.

Animals↗

PubMed1999

Direct injection HPLC analysis of some non-steroidal anti-inflammatory drugs on restricted access media columns.

Direct serum injection methods are described for the HPLC determination of selected non-steroidal anti-inflammatory drugs (NSAIDS) on restricted access media (RAM) columns, using either a Pinkerton (ISRP) or semi-permeable surface (SPS) column. Twenty microlitres of a filtered serum sample was injected directly onto each column. Calibration curves were prepared for ketoprofen (1-20 micrograms/mL), fenbufen (0.8-20 micrograms/mL), sulindac (0.8-20 micrograms/mL) and probenecid (1.5-40 micrograms/mL) on the SPS column, and nabumetone (1.5-40 micrograms/mL) and indomethacin (1.5-40 micrograms/mL) on the Pinkerton column. The percentage error and imprecision of the methods were found to be less than 10%. The inter- and intra-day variability for analytes were in the range of 0.15-10%. The limits of quantitation and detection were in the range of 800-1500 and 300-800 ng/mL, respectively, for the analytes studied. A hydrophobic shielded phase (Hisep) column was also investigated and was found to be generally too retentive (> 29 min) for assay of these analytes.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1999

Risk factors accelerating cerebral degenerative changes, cognitive decline and dementia.

OBJECTIVES: Factors accelerating cerebral degenerative changes represent potentially modifiable risks for cognitive decline. Putative risk factors accelerating subtle cognitive decline and dementia were correlated with repeated measures of cerebral atrophy, CT densitometry, perfusions and cognitive testing among neurologically and cognitively normative ageing volunteers. METHODS: Two hundred and twenty-four normative subjects at increased risk for cognitive decline were admitted to the study. Mean entry age was 59. 5+/-15.8 years. Mean follow-up is 4.3+/-3.1 years. At follow-up, 22 developed subtle cognitive decline (deltaCCSE>/=-3), 19 became demented, eight with vascular type (VAD) and 11 with Alzheimer's type (DAT) and 183 remain cognitively unchanged. Standardized questionnaires, medical, neuropsychological, neurological and blood work examinations were obtained. Cerebral atrophy, tissue densities and perfusions were measured by xenon-enhanced CT. RESULTS: After age 60, cerebral atrophy, ventricular enlargement, polio- and leuko-araiosis geometrically increased as perfusions declined. Risk factors accelerating perfusional decline, cerebral atrophy, polio-araiosis and leuko-araiosis (thinning of grey-white matter densities) were: transient ischaemic attacks (TIAs), hypertension, smoking, hyperlipidemia, male gender. At age 71.5+/-11.9, subtle cognitive decline began, accelerated by TIAs, hypertension and heart disease. Leuko-araiosis began before cognitive decline. TIAs, hypertension and hyperlipidemia correlated with VAD. Excessive cortical perfusional decreases and cerebral atrophy correlated with cognitive decline. Family history of neurodegenerative disease correlated with DAT. CONCLUSION: TIAs, hypertension, hyperlipidemia, smoking and male gender accelerate cerebral degenerative changes, cognitive decline and dementia.

Adult↗

PubMed1999

Protection against lethal toxoplasmosis in mice by an avirulent strain of Toxoplasma gondii: stimulation of IFN-gamma and TNF-alpha response.

In this study, we examined whether the PTN strain (isolated from an AIDS patient) of Toxoplasma gondii could induce cross-protection in mice against infection with a lethal dose of the PLK strain. Mice were first infected with tachyzoites (5 x 10(5)) of PTN and 5 days later challenged with PLK (1 x 10(5), LD(90)) parasites. None of these mice succumbed to infection until day 21 after infection, whereas 100% of the mice given the same dose of PLK infection alone died between 5 and 11 days after infection. The protection was accompanied by an increased expansion of NK cells and CD4 + T cells. This condition was associated by increased production of IFN-gamma and an augmented number of IFN-gamma-producing cells in the spleen. Further, PTN + PLK-infected mice showed higher production of TNF-alpha and nitrite compared to PLK-infected mice. Mice infected with the PTN strain had an enhanced capacity to activate the immune system early in infection since they produced higher levels of IFN-gamma, TNF-alpha, and NO than PLK-infected mice. Administration of anti-IFN-gamma mAb or anti-asialo GM1 antibody resulted in 100 and 20% mortality, respectively, in PTN-infected mice but no death in PTN + PLK-infected mice. Together, these results suggest that early production of IFN-gamma and NK-cell activity is important in protection against PTN infection, whereas in PTN + PLK infection components of adaptive immunity rapidly developed following elaboration of an effective early innate immune response.

Animals↗

PubMed1999

Determination of ephedrine, theophylline and phenobarbital in a tablet dosage form by capillary electrophoresis.

A capillary electrophoresis method was developed to separate and quantitate ephedrine (ED), theophylline (TP) and phenobarbital (PB) in a tablet dosage form. Tablets were ground and extracted with methanol using ultrasonication. Aliquots of standard stock solution were hydrodynamically injected for 5 s at the anodic end. Separation was performed on a fused silica capillary (72 cm x 50 microm i.d.; 50 cm to detector) at an applied voltage of 20 kV with a phosphate run buffer (pH 8.0, 50 mM). Analysis was performed at ambient temperature (23+/-1 degrees C) and the total run time was 9 min with detection at 220 nm. Calibration curves were prepared for ED, TP and PB with methyl p-hydroxy benzoate as internal standard. For each analyte, the correlation coefficients were >0.999 (n = 4). The RSD% of ten replicate injections for each analyte were <1%. The method was applied to the quantitation of ED, TP and PB in a commercial tablet dosage form.

Calibration↗

PubMed1999

Trauma and arteriovenous malformation of the brain - a problem in medico-legal practice.

Legal difficulties can always arise when a death, owing to a pre-existing natural disease, follows trauma. Arteriovenous malformations of the brain are well known to rupture spontaneously, causing severe and often fatal cerebral haemorrhage. When such rupture is preceded by head injury, it is necessary to consider whether the rupture was coincidental or a direct result of the physical injury sustained. The standard of evidence required for criminal conviction in such cases must be 'beyond any reasonable doubt'. The present article discusses the relationship between physical trauma and cerebral arteriovenous malformation in an adult male who died following an alteration with a colleague that resulted in his being punched in the face, falling down and hitting his head.

Journal Article↗