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Biomedical subjects

I Ahmed

Publications and source records attributed to I Ahmed.

At least 109 records · Page 6Linked to original sources
PubMed1998

Multiplicity and tissue specific expression of camel cytochrome P450(s).

The presence of multiple forms of the cytochrome P450 was demonstrated enzymatically in camel tissues using a variety of isoenzyme specific substrates and immunochemically using isoenzyme specific antibodies. The maximum catalytic activity using xenobiotics as substrate was observed in the liver followed by the kidney. However, lauric acid hydroxylation was found to be higher in the kidney than in any other tissues. Camel liver microsomal monooxygenase activity using aniline, aminopyrene, ethoxycoumarin, ethoxyresorufin and benzo(a)pyrene as substrates was comparable with those of rat and human livers. The activity of the enzymes in extrahepatic tissues of the camel was comparable with those of the rat extrahepatic tissues. The maximum expression of P450 protein was seen in the camel liver and kidney while the brain and intestine exhibited relatively low levels of expression. P450 expression in camel tissues appeared to be higher than in rat tissues. Immunohistochemical staining of P450 in the camel liver, kidney and brain confirmed the higher expression of P450 enzyme proteins in the liver and kidney as compared to other extrahepatic tissues. The maximum expression of P450 in the liver was observed in hepatocytes around the central vein and in the kidney it was observed in the proximal tubules. These results demonstrate that the multiple forms of P450s are differentially expressed in camel tissues and that the relative levels of expression are comparable with those of rat and human tissues. These observations may be important in understanding the differential susceptibility of camel tissues to the toxic/therapeutic effects of xenobiotics/drugs and environmental pollution.

Animals↗
PubMed1998

The specificity of proneural genes in determining Drosophila sense organ identity.

The proneural genes (atonal and the genes of the achaete-scute complex (AS-C)) are required for the selection of sense organ precursors. They also endow these precursors with sense organ subtype information. In most of the ectoderm, atonal is required for precursors of chordotonal sense organs, whereas AS-C are required for those of most external sense organs, such as bristles. To address the question of how proneural genes influence subtype identity, we have made use of the Gal4/UAS system of misexpression. Unlike previous misexpression experiments, we found that under specific conditions of misexpression, atonal shows high subtype specificity of ectopic sense organ formation. Moreover, atonal can even transform wild-type external sense organs to chordotonal organs, although scute cannot perform the reciprocal transformation. Our evidence demonstrates that atonal's subtype determining role is not to activate directly chordotonal fate, but to repress the activation of cut, a gene that is necessary for external sense organ fate, thereby freeing its precursors to follow the alternative chordotonal organ fate.

Animals↗
PubMed1998

Vitamin D status of breastfed Pakistani infants.

This study was conducted to evaluate the vitamin D status of healthy breastfed Pakistani infants and their nursing mothers. Sixty-two breastfed healthy infants and their nursing mothers belonging to the upper and lower socioeconomic classes were examined. Serum 25-hydroxy vitamin D [25(OH)D], serum calcium, phosphorus and alkaline phosphatase were measured. The mean serum 25(OH)D in infants was 34.59 +/- 26.56 nmol/l. Fifty-five percent of infants and 45% of mothers had very low serum 25(OH)D levels (<25 nmol/l). Significantly higher levels were found in infants of lower socioeconomic class (p < 0.001) and in those living in mud houses (p = 0.002) and infants >6 months (p < 0.001). A high prevalence of vitamin D deficiency was found in breastfed infants and nursing mothers, predominantly among those belonging to the upper socioeconomic class. Infants of the lower socioeconomic class had comparatively higher serum 25(OH)D levels, but even these levels were below the normal range for infants (90 +/- 27.5 nmol/l).

Alkaline Phosphatase↗
PubMed1998

Intercessory Prayer for ill Health: A Systematic Review.

OBJECTIVES: To review the effectiveness of prayer as an additional intervention for those with health problems already receiving standard medical care. SEARCH STRATEGY: Electronic Searches of Biological Abstracts, CINAHL, The Cochrane Controlled Trials Register, EM-BASE, MEDLINE, PsycLIT, and Sociofile were undertaken. All references of articles selected were searched for further relevant trials. SELECTION CRITERIA: Randomised and quasi-randomised trials of personal, focused, committed and organised intercessory prayer on behalf of anyone with a health problem were considered. Outcomes such as achievement of desired goals, death, illness, quality of life and well-being for the recipients of prayer, those praying and the caregivers were sought. DATA COLLECTION AND ANALYSIS: Studies were reliably selected and assessed for methodological quality. Data were extracted by 4 reviewers working independently. Dichotomous data were analysed on an intention-to-treat basis, and continuous data with over 50% completion rate are presented. MAIN RESULTS: There was no evidence that prayer affected the numbers of people dying from leukaemia or heart disease (OR 0.64, CI 0.32-1.27), or that it decreased coronary care complications (OR 1.05, CI 0.49-2.26) or the time participants stayed in hospital. There were significantly fewer 'intermediat//poor outcomes' for those with heart disease in the prayed-for group (OR 0.49, CI 0.30-0.80), and this finding was robust to some changes in definition. CONCLUSIONS: This review provides no guidance for those wishing to uphold or refute the effect of intercessory prayer on the outcomes studied in the available trials. Therefore, in the light of the best available data, there are no grounds to change current practices. There are very few completed trials of the value of intercessory prayer. The evidence presented so far is interesting enough to justify further study. If prayer is seen as a human endeavour it may or may not be beneficial, and further trials could uncover this. It could be the case that any effects are due to elements beyond present scientific understanding that will, in time, be understood. If any benefit derives from God's response to prayer it may be beyond any such trials to prove or disprove.

Journal Article↗
PubMed1998

Cytosine arabinoside-induced vasculitis.

Dermatologic side effects of cytosine arabinoside (ara-C) are rare and most commonly occur after high-dose (more than 100 to 200 mg/m2 per day) therapy has been administered for several days. Although vascular reactions after combination chemotherapeutic regimens with ara-C have been anecdotally described, they have not been previously reported after single-agent chemotherapy with ara-C. Herein we describe two patients with acute nonlymphoblastic leukemia in whom cutaneous small vessel necrotizing vasculitis developed after high-dose single-agent chemotherapy with ara-C. Cutaneous lesions developed 3 to 5 days after initiation of therapy and resolved spontaneously within a week after the chemotherapeutic regimen was completed. No evidence of systemic vasculitis was present in either patient. Prior experimental data have demonstrated a direct toxic effect of ara-C on endothelial cells, and this outcome may represent the underlying mechanism of vascular injury.

Adult↗
PubMed1998

Posttraumatic Psychosis.

There are about three million cases of traumatic brain injury in the US each year. These patients have between two to five times greater risk of developing psychosis than the general population. In this report, we explore the limited number studies examining the incidence of psychosis in different populations. These studies were primarily retrospective and involved both veterans and civilians suffering from different types of injuries, penetrating or open and closed head injuries. Posttraumatic psychosis can occur several years after the head injury and the relationship between the injury and the psychosis is not always clear. In this report, we explore this relationship from the standpoint of risk factors for the development of psychosis. These may be lesion-specific such as the extent of the injury, laterality of lesion, as well as others such as genetic vulnerability and comorbid epilepsy, which actually may be an intervening variable between the brain injury and the onset of late-onset psychosis. Treatment is based on limited data and consists of both pharmacologic and nonpharmacologic approaches. Pharmacologic treatment of posttraumatic psychosis consists of symptomatic, functional, and hypothetical approaches. Specific pharmacologic treatment consists of antipsychotics, or antikindling anticonvulsants, or a combination thereof. Nonpharmacologic approaches such as cognitive retraining and behavioral treatment are oriented towards improving functioning and teaching adaptive coping strategies.

Journal Article↗
PubMed1998

The pharmacological effects of ginkgo biloba, a plant extract, on the brain of dementia patients in comparison with tacrine.

In 1994, a standardized dry extract of Ginkgo biloba leaves (SeGb), has been approved by German health authorities for the treatment of primary degenerative dementia and vascular dementia. More than 24 different brands of Ginkgo biloba extract are sold in the United States. Tacrine, also known as tetrahydroaminoacrine (THA), and donepezil are currently the only drugs approved in the United States for the treatment of Alzheimer's disease. Previous studies demonstrated that SeGb and tacrine induce significant pharmacological effects on the brains of young, healthy human males, as determined by bioelectrical activity measurements obtained using the quantitative pharmaco-electroencephalogram (QPEEG) method. The type of central nervous system (CNS) effects we have seen on computer-analyzed EEGs (CEEGs) after administration of tacrine or EGb suggests both are "cognitive activators" which are, as a class of products, characterized by a (prepost) relative increase of 7.5 to 13 Hz ("alpha") and decrease of 1.3 to 7.5 Hz ("delta" and "theta") activity. To determine whether EGb or tacrine had noticeable pharmacological effects on elderly subjects diagnosed with possible or probable Alzheimer's, the present open, uncontrolled trial was conducted. Data from 18 subjects (11 males, 7 females) at an average age of 67.4 years with light to moderate dementia (Mini Mental mean score = 23.7, ranges: 15-29 [Geriatric Depression Scale mean scores = 3.7; range: 3.2-5.4]) were analyzed for this presentation. Each subject was randomly administered a single oral "Test-Dose" of either 40 mg of tacrine or 240 mg of EGb2 in two separate sessions within 3- to 7-day intervals. Before drug administration and at 1- and 3-hour intervals after drug administration, CEEGs were recorded for a minimum of 10 minutes. The CEEGs were analyzed using Period Analysis programs we developed for QPEEG. The results indicated that both EGb and, to a lesser degree, tacrine induced pharmacological effects, as established by QPEEG measurements, in the CNS similar to those previously established in healthy, young subjects. The type of CNS effects produced by EGb (as established by HZI's CEEG psychotropic drug database) in elderly dementia patients were similar to those induced by tacrine responders as well as those seen after the administration of other "cognitive activators" (pramiracetam, vinpocetine, BMY-21502, suloctidil, and lisuride) and anti-dementia drugs approved in the United States or Europe (tacrine, donepezil, nimodipine, piracetam, and oxiracetam) from our database. The results also showed that 240 mg of EGb has typical cognitive activator CEEG profiles (responders) in more subjects (8 of 18) than 40 mg tacrine (3 of 18 subjects). Because of the small sample size, we could not test the hypothesis that subjects who showed cognitive activator-type pharmacological response to the first Test-Dose of EGb or tacrine also exhibit more therapeutic effects (compared to nonresponders) when drugs are administered chronically.

Aged↗
PubMed1998

Maternal vitamin-D deficiency in Pakistan.

OBJECTIVE OF THE STUDY: This study was performed to assess the vitamin D status of healthy Pakistani nursing mothers and their breastfed infants. METHODS: Seventy-one nursing mothers and their breastfed infants belonging to upper and lower socio-economic class were examined 6 weeks to 11 months after delivery. Serum 25-hydroxy vitamin D [25(OH)D], serum calcium, phosphorus and alkaline phosphatase were measured. RESULTS: The mean serum 25(OH)D in mothers was 36.7+/-32.4 nmol/L and 41.25+/-35.4 nmol/ L in infants. Thirty-four (48%) mothers and 37 (52%) infants had levels less than 25 nmol/ L. Significantly higher levels were found in uneducated mothers (p=0.01), mothers of lower socio-economic class (p<0.001) and in those living in mud houses (p<0.001). A significant correlation was found between serum 25(OH)D levels of infants under three months of age and their mothers (p<0.01). CONCLUSIONS: High prevalence of vitamin D deficiency was found in nursing mothers and their infants predominantly in the upper socioeconomic class.

Adult↗
PubMed1997

A short-term trial of tacrolimus ointment for atopic dermatitis. European Tacrolimus Multicenter Atopic Dermatitis Study Group.

BACKGROUND: Tacrolimus (FK 506) is an effective immunosuppressant drug for the prevention of rejection after organ transplantation, and preliminary studies suggest that topical application of tacrolimus is effective in the treatment of atopic dermatitis. METHODS: We conducted a randomized, doubleblind, multicenter study that compared 0.03 percent, 0.1 percent, and 0.3 percent tacrolimus ointment with vehicle alone in patients with moderate to severe atopic dermatitis. The ointment was applied twice daily to a defined, symptomatic area of 200 to 1000 cm2 of skin for three weeks. The primary end point was the change in the summary score for erythema, edema, and pruritus between the first and last days of treatment. RESULTS: After three weeks of treatment, the median percentage decrease in the summary score for dermatitis on the trunk and extremities was 66.7 percent for the 54 patients receiving 0.03 percent tacrolimus, 83.3 percent for the 54 patients receiving 0.1 percent tacrolimus, 75.0 percent for the 51 patients receiving 0.3 percent tacrolimus, and 22.5 percent for the 54 patients receiving vehicle alone (P<0.001). The results for the face and neck were similar. The differences among the three tacrolimus groups were not statistically significant. A sensation of burning at the site of application was the only adverse event that was significantly more frequent with tacrolimus than with vehicle alone (P<0.001). Throughout the study, most patients in all three tacrolimus groups had blood concentrations of tacrolimus below 0.25 ng per milliliter. The highest concentration was 4.9 ng per milliliter, which was reported in the group receiving 0.3 percent tacrolimus. CONCLUSIONS: The short-term application of tacrolimus ointment is effective in the treatment of atopic dermatitis, with the sensation of burning being the main side effect.

Administration, Cutaneous↗
PubMed1997

p53 tumor suppressor protein and tissue proliferative fraction in infiltrating duct carcinoma.

BACKGROUND AND OBJECTIVES: Breast cancer continues to frustrate oncologists worldwide. In India, it is the second most common neoplasm among women and is increasing in incidence. Several molecular markers have been associated with a poor prognosis in patients with breast cancer, and the presence of these markers is often thought to provide information on the biological behavior of the malignant breast tumor. Much attention has recently been focused on the tumor suppressor gene p53. Mutation or alteration in this gene leads to the loss of negative growth regulation and hence to rapid cell proliferation. The present study was designed to evaluate the connection between expression of the p53 protein and its relation to the tissue proliferative compartment as measured by expression of the proliferating cell nuclear antigen (PCNA). METHODS: Expression of p53 and PCNA were detected by immunocytochemistry in paraffin-embedded sections of infiltrating duct carcinoma and control breast tissue (normal tissue and adenoma). RESULTS: A significant correlation was observed between expression of p53 and PCNA. A significant correlation was also observed between expression of p53 and grade of tumor and stage of disease. CONCLUSIONS: Our results support the hypothesis that accumulation of p53 is associated with a high tumor proliferation rate an association that might be expected in view of the role of wild p53 as a negative regulator of cell proliferation.

Adenoma↗
PubMed1997

Photosensitive lichenoid reaction to torsemide--a loop diuretic.

Torsemide, a potent loop diuretic of the sulfonylurea class, has been available for clinical use in the United States since 1993. Adverse generalized and cutaneous reactions to this medication are uncommon and are usually mild and transient. In this article, we describe an 82-year-old man who had a photosensitive lichenoid reaction due to torsemide therapy, a previously undescribed phenomenon. The overwhelming presence of T lymphocytes within the lesional skin biopsy specimen and the photodistributed nature of the eruption supported a localized photoallergic cell-mediated hypersensitivity reaction to torsemide. The presumed epitope targeted in this reaction is unclear. Because of the potential risk for cross-reactivity of torsemide with the sulfonamide group of medications, torsemide should be used cautiously in sulfonamide-hypersensitive patients.

Aged↗
PubMed1997

Ovarian malignancy in patients with dermatomyositis and polymyositis: a retrospective analysis of fourteen cases.

BACKGROUND: Dermatomyositis and polymyositis can be associated with an underlying malignancy. OBJECTIVE: Our purpose was to describe a group of patients with dermatomyositis and polymyositis in whom ovarian carcinoma was diagnosed and to evaluate further the characteristics of the association between these diseases. METHODS: A cross-sectional retrospective review identified 14 patients in a 45-year period (1950 to 1995) with dermatomyositis and polymyositis in whom an underlying ovarian malignancy was diagnosed. Clinical and laboratory data of these patients were reviewed, and immunofluorescent and hematoxylin-eosin-stained skin sections were examined. RESULTS: The mean age at diagnosis of dermatomyositis and polymyositis was 59 years. Of the 14 patients, 11 had dermatomyositis, two had polymyositis, and one had an overlap disease. The 12 patients with dermatomyositis had distinctive cutaneous lesions. In eight, cutaneous biopsy specimens demonstrated variable histologic changes. Thirteen patients had signs of proximal muscle weakness, and myopathy was further demonstrated by electromyographic testing in 10. Creatine kinase levels were increased in 6 of the 10 patients tested. Dysphagia was present in five patients, but esophageal dysmotility was not demonstrated in three. Dermatomyositis and polymyositis preceded the ovarian malignancy in nine patients, were concomitant with it in four, and succeeded the ovarian disease in one. CONCLUSION: Physical examination and imaging techniques failed to detect early ovarian cancer in our patients with dermatomyositis and polymyositis. When detected (usually by abdominopelvic examination, in two by computed tomographic examination), it was advanced, and survival was poor.

Adenocarcinoma↗
PubMed1997

Care of asthma: allergy clinic versus emergency room.

BACKGROUND: Demographic and socioeconomic factors have an impact upon the morbidity and mortality rates of asthma in inner-city pediatric populations. Many pediatric patients with asthma use the emergency room as their primary care physician, while a smaller number of children with asthma use the allergy-immunology clinic. OBJECTIVE: We examined the demographic and socioeconomic characteristics of asthmatic patients using the emergency room as their primary care physician and of those attending the allergy-immunology clinic in the same inner-city hospital. We compared the morbidity and cost of care of asthmatic patients who received their medical care in the emergency room to that of those who received their care in the allergy-immunology clinic. METHODS: Fifty consecutive emergency room patients and 25 clinic patients were studied using an identical questionnaire. RESULTS: There was no difference between the two groups in the total number of individuals per household, children per family, monthly income, type or size of dwelling, financial problems purchasing medications, health insurance type, distance to the medical center, or education of the caretaker. Severity of asthma was not different in the two groups before the start of the study. The only significant demographic difference was in age: 10.6 years for the clinic group and 7.8 years for the emergency room group (P < .002). Clinically, in the year preceding the interview, the clinic group had significantly less nocturnal cough (P < .025), sleep interruption (P < .001), weekly asthma (P < .05), and emergency room visits (P < .09). The allergy clinic group had an approximate average savings of $137 per patient per year. Hospital admissions and emergency room costs were increased by a small group of three allergy clinic patients, decreasing the difference in the cost of care between the two groups. CONCLUSION: The data showed that patients who attended the emergency room and those who attended the allergy-immunology clinic were not demographically or socioeconomically different. The decreased morbidity of asthma and cost of care for the allergy clinic patients, as opposed to the emergency room patients, are likely due to the care given in the allergy-immunology clinic.

Allergy and Immunology↗
PubMed1997

The incidence of post-vasectomy chronic testicular pain and the role of nerve stripping (denervation) of the spermatic cord in its management.

OBJECTIVE: To assess the incidence of chronic postvasectomy testicular pain (CPTP) and evaluate the use of denervation of the spermatic cord in its management. PATIENTS AND METHODS: A retrospective postal survey of 560 patients (mean age 36 years, range 25-55; mean time since vasectomy 19 months, range 8-39) who underwent vasectomy between July 1992 and December 1994 was carried out to determine the incidence of CPTP. A prospective study was conducted in a further group of 17 patients (mean age 43 years, range 34-60), who had had CPTP for at least one year, to evaluate the effectiveness of nerve stripping of the spermatic cord in relieving pain. RESULTS: Of 396 replies, 108 (27.2%) patients complained of some testicular pain following their vasectomy operation. In 88 (82%) of these 108 patients the pain was brief and was not defined as CPTP, while 20 (19%) patients had pain for > 3 months; 33 (31%) patients required analgesics to control the pain. Of the 17 patients who underwent spermatic cord denervation, 13 reported complete relief of pain at their first follow-up visit and were discharged. Four patients had a significant improvement in the symptom score and were satisfied with the results. CONCLUSIONS: There is a small but significant incidence of CPTP and patients should be warned of this possibility when counselled before operation. Denervation of the spermatic cord seems to be a viable surgical option for patients with CPTP who fail to respond to conservative measures.

Adult↗