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Biomedical subjects

A Asghar

Publications and source records attributed to A Asghar.

17 recordsLinked to original sources
PubMed2005

Diltiazem inhibits human intestinal cytochrome P450 3A (CYP3A) activity in vivo without altering the expression of intestinal mRNA or protein.

AIMS: To determine the effect of diltiazem on intestinal CYP3A activity and protein and mRNA expression in vivo in healthy subjects. METHODS: Intestinal biopsies were obtained from ten healthy controls and from ten healthy subjects after receiving diltiazem 120 mg bid for 7 days. Intestinal CYP3A activity, CYP3A4 protein and mRNA concentrations were quantified in both groups. Intestinal CYP3A activity was determined by incubation of small bowel homogenate with midazolam (25 microM) and NADPH for 5 min and the rate of formation of 1'-hydroxymidazolam was quantified. RESULTS: All subjects in the treatment group had detectable diltiazem concentration in the serum. While there was no significant difference in CYP3A4 protein and mRNA expression between the control and treatment groups, the formation of 1'-hydroxymidazolam (446 pmol min(-1) mg(-1) 6 (control) vs. 170 (CI 112, 228) pmol min(-1) mg(-1) 95% confidence interval (CI 269, 623) (diltiazem group)) was significantly reduced (P < 0.05). CONCLUSION: Diltiazem decreased small bowel CYP3A activity by 62% as a result of irreversible inhibition with no corresponding change in intestinal CYP3A4 mRNA or protein concentrations.

Adult↗
PubMed1999

Detection of Helicobacter pylori DNA in fecal samples from infected individuals.

Stool, gastric biopsy, and serum samples were collected from 22 subjects. DNA from stool was extracted, amplified, and hybridized with primers specific for the 16S rRNA gene of Helicobacter pylori. DNA from gastric biopsy specimens was analyzed similarly for comparison. Universal primers were used to confirm successful extraction of DNA from samples. Histologic, serologic, and DNA analyses were scored in a blinded fashion. Universal primer amplification verified successful DNA extraction from all stool and gastric tissue specimens. The gastric tissue DNA assay was positive for H. pylori in 11 of the 22 subjects, correlating completely with histologic and serologic results. Stool DNA was positive for H. pylori by our molecular assay in 8 of these 11 H. pylori-positive subjects. All subjects who were negative by histologic, serologic, and gastric tissue DNA analyses were also negative by stool DNA analysis. Compared to histology, serology, and gastric tissue DNA analyses, the sensitivity of our stool DNA assay was 73%, with a specificity of 100%.

DNA, Bacterial↗
PubMed1997

Smoking in Oklahoma: the seven-year trend.

BACKGROUND: The serious health consequences of smoking have been known to us for more than 30 years. Every year, research brings forth more serious consequences of this risk factor. These are reviewed by us. The year 2000 will soon be with us. We need to know where we stand in relation to the year 2000 objectives with regard to smoking. STUDY DESIGN: The study design is cross-sectional. METHODS: This study is based on the data obtained during the years 1989 through 1995 from the Oklahoma Behavioral Risk Factor Surveillance System. RESULTS AND CONCLUSIONS: There has been a significant decrease in the prevalence of smoking in Oklahoma in the last seven years. Although there has been no significant change in smoking among females in the last seven years, smoking among males has dropped significantly, especially in the last two years of the study, 1994 and 1995. The prevalence of smoking in 1995 was the same among males and females, at about 22%. In age groups 18-24 and 25-34, there has been no significant change in smoking since 1990. The prevalence of smoking is related to the level of education; the higher the education the lower the prevalence of smoking. Smoking among those with college or higher level education has remained at about the same level, 15%, in the last seven years. Among those with less than high school education, smoking has remained the same at about 30% over the last seven years. Prevalence of smoking is the highest among American Indians. Smoking among whites (non-Hispanic) shows a significant decrease from about 26% in 1990-91 to about 22% in 1994-95. Among white males, smoking has significantly dropped from 31% in 1989 to about 22% in 1995. In 1995, smoking was almost the same in the two sexes at about 22%. We need to achieve a reduction of 7% in the overall prevalence rate of smoking in the coming years to achieve the Year 2000 objective. To effect this reduction, our efforts at health promotion and community mobilization will have to be strengthened. Further, with the prevalence rate of around 25% in 1995 among women of reproductive age, and the year 2000 target of 12%, it is apparent that very strenuous efforts will have to be made among this group in our population to achieve Year 2000 objectives.

Adolescent↗
PubMed1996

Characterization of the APC gene in sporadic gastric adenocarcinomas.

The prominent role of the APC gene in colorectal tumor development is well established. However, its role in tumorigenesis in other tissues is not clear. Hence, DNA from 30 primary sporadic gastric adenocarcinomas was obtained from patients living in a high risk area of the world (North-Central Italy) in order to further define APC's role in gastric tumorigenesis. We thoroughly examined that region of APC which is commonly mutated in colorectal tumors using proven sensitive methods. The IVS protein assay and DNA sequence analysis of APC codons 686 through 1693 revealed no intragenic mutations. However, allelic loss of loci near APC was detected in 7 (28%) of 25 informative gastric adenocarcinomas using two 5q dinucleotide repeat markers for LOH analysis. These results suggest that genetic alteration of a region of APC commonly mutated in colorectal cancer is not a common event during sporadic gastric tumor development, at least in patients from North-Central Italy. Further analysis of chromosome 5q might identify another gene to be significantly altered in these gastric cancers.

Adenocarcinoma↗
PubMed1996

Prevalence of overweight and associated factors among Oklahomans.

BACKGROUND: Obesity among adults in the, United States has been increasing for the last three decades. Overweight is associated with numerous health risks such as diabetes, atherosclerosis, hypertension, sedentary lifestyle, etc. It also throws a very heavy economic burden on society, estimated at $39.3 billion in 1986. OBJECTIVE: To estimate the prevalence of obesity and its associated factors so that efforts to achieve the Healthy Oklahomans 2000 objectives may be brought into sharper focus. STUDY DESIGN: The study design is cross-sectional. METHODS: The study is based on the data from the Behavioral Risk Factor Surveillance System (a three-stage cluster sample survey) for the years 1991 through 1994. Statistical analysis was done with SUDAAN software for complex survey. RESULTS: More than 25% of Oklahomans are overweight. To reach the Year 2000 objectives, a reduction of 10% in overweight will have to be achieved in about three and one-half years. Prevalence of moderate obesity among women is higher than among men. Prevalence of severe obesity is higher among the black community than among other communities. However, prevalence of moderate obesity is the same among blacks and whites. Severe obesity is significantly higher among those with less than a high school education than among those with college education. The prevalence of moderate obesity among non-smokers is significantly higher than among smokers. Among the severely obese, hypertension is more than twice as prevalent as normal blood pressure. Among the moderately obese, high blood pressure is more than one and one-half times more prevalent than normal blood pressure. Obesity increases with age in a predictive manner; it drops after the age of 54. Moderate obesity is significantly higher among women who have had a hysterectomy than those who have not had a hysterectomy. Prevalence of severe obesity as well as moderate obesity is very much higher among diabetics than among non-diabetics. A large proportion of severely obese people are physically inactive. We did not find an association between consumption of fruits and vegetables as a part of normal diet and prevalence of obesity. CONCLUSION: Strenuous and focused efforts need to be made among the vulnerable groups, in view of the short time left until year 2000, to reduce the prevalence of obesity to the level laid down in the Year 2000 objectives.

Adult↗
PubMed1995

Smoking: high hazards in high school.

BACKGROUND: Young people in school are at an impressionable age, peer pressures are intense, and the probability that they will pick up a high-risk behavior, such as smoking, is high. The key to reduction of smoking among adults is to target our prevention efforts at young adults and teens. OBJECTIVE: To study the prevalence and trend of smoking among young adults and teens and to formulate guidelines on smoking reduction to guide those who counsel young people. STUDY DESIGN: The study design is cross sectional. METHODS: This study is based on the data from the Oklahoma Behavioral Risk Factor Surveillance System and the National Youth Risk Behavioral Surveillance System - the two systems that monitor the prevalence of behaviors that most influence health. RESULTS: The prevalence of smoking among young adults (age 18-24) in Oklahoma is high at more than 21%. The disturbing feature is that it is higher among young females than among young males. The prevalence of smoking among young adults is the highest among high school dropouts and is more than 38%. It is lower among high school graduates (about 28%) and lowest among college graduates (about 18%). The percentage of smoking among students who classify themselves as current smokers rises from 23% to 30% as the students progress from grade 9 to 12 and the percentage of frequent smokers increases from 8% to 16%. CONCLUSIONS: Guidelines suggested for counselors are: 1. Along with smoking, look for comorbid behaviors such as alcohol use, drug abuse, and high-risk sexual behavior. 2. Ask whether the student has easy access to free cigarette samples. 3. Check whether the teen is trying to lose weight; suggest appropriate methods for losing weight if smoking is being used for losing weight. 4. Target health education efforts early in a student's school career starting in elementary school, but concentrate especially at the 8th or 9th grade level to have maximum preventive impact.

Adolescent↗
PubMed1989

Influence of oxidised dietary oil and antioxidant supplementation on membrane-bound lipid stability in broiler meat.

1. The effects of oxidised oil, dietary alpha-tocopherol and BHA/BHT-supplementation on the fatty acid composition of mitochondrial, microsomal and soluble protein fractions of broiler muscles, and on their lability to metmyoglobin/hydrogen peroxide-catalysed peroxidation were investigated. 2. Oxidised oil in the broiler diets induced rapid oxidation of the membrane-bound lipids and decreased their stability towards metmyoglobin-hydrogen peroxide-catalysed peroxidation. 3. Supplementation of the broiler diets with alpha-tocopherol increased the alpha-tocopherol concentrations in the microsomal and soluble protein fractions of the dark meat as well as the soluble protein fraction of the white meat. This, in turn, stabilised the membrane-bound lipids against metmyoglobin/hydrogen peroxide-initiated peroxidative changes.

Animals↗
PubMed1989

Effects of oxidised dietary oil and antioxidant supplementation on broiler growth and meat stability.

1. Broilers were fed on diets containing oxidised sunflower oil, sunflower oil and sunflower oil supplemented with alpha-tocopherol, butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT). 2. Oxidised oil caused a significant reduction in broiler body and carcase weights, whereas alpha-tocopherol and BHA/BHT supplementation improved growth. 3. Meat samples from these broilers were stored at 4 degrees C and -20 degrees C and their oxidative stability evaluated. Feeding oxidised oil to broilers resulted in meat that underwent rapid oxidative changes during refrigerated and frozen storage. 4. On the other hand, dietary alpha-tocopherol and BHA/BHT supplementation increased alpha-tocopherol and BHA/BHT concentrations in meat and significantly (P less than 0.05) improved the oxidative stability of meat during refrigerated and frozen storage.

Animals↗
PubMed1989

The role of shigella spp. in childhood diarrhoea in Iran and their antibiotic resistance.

The incidence of shigellae was measured in 445 children with diarrhoea in Sanandaj, Kordestan, and 715 in Tehran during a 1-year study. 18 (4%) patients in Sanandaj and 41 (5.7%) patients in Tehran were positive for various shigella species. Sh. boydii (7 strains) and Sh. sonnei (25 strains) were the commonest species in Sanandaj and Tehran respectively. Among the isolates from Sanandaj the highest resistance was to tetracycline (55.5%), whereas in Tehran it was to sulfamethoxazole/trimethoprim (68.3%).

Child, Preschool↗
PubMed1985

Functionality of muscle proteins in gelation mechanisms of structured meat products.

Recent advances in muscle biology concerning the discoveries of a large variety of proteins have been described in this review. The existence of polymorphism in several muscle proteins is now well established. Various isoforms of myosin not only account for the difference in physiological functions and biochemical activity of different fiber types or muscles, but also seem to differ in functional properties in food systems. The functionality of various muscle proteins, especially myosin and actin in the gelation process in modal systems which simulate structured meat products, is discussed at length. Besides, the role of different subunits and subfragments of myosin molecule in the gelation mechanism, and the various factors affecting heat-induced gelation of actomyosin in modal systems are also highlighted. Finally, the areas which need further investigation in this discipline have been suggested.

Actinin↗
PubMed1984

Age, species, breed, sex, and nutrition effect on hide collagen.

The hide of an animal previously used for leather may be upgraded in value through its expanded use as a food additive. While not a complete protein, collagen--the main protein of hide--may provide desirable functional properties within a food system. This protein is now abundant and will increase as new forms of meat become prevalent. Along with hide, collagen is being generated from hand-separated meat for restructuring, desinewed meat, and bone. This review paper is designed to learn more about the effect of animal age, species, breed, sex, and nutrition on hide collagen. There is general agreement that age not only causes an increase in physical strength of the collagen fiber, through altering the degree of cross-linking, but the quantity of soluble and insoluble collagen also changes.

Aging↗
PubMed1982

Post-mortem stimulation of carcasses: effects on biochemistry, biophysics, microbiology, and quality of meat.

The influence of post-mortem electrical stimulation of carcasses on the physicochemical, ultrastructural, microbiological, and quality characteristics of meat have been described at length. The latest views, based on the physiological, biochemical, and mechanical models that have been extended to explain the development of tension (contraction) in muscle are presented. The mechanisms by which electrical stimulation causes improvement in certain quality characteristics of meat are considered with some new thoughts. The significance of the mode of electrical flow through the carcass and how the various electrical parameters (electrode-carcass contact, type of current, voltage, pulse characteristics) affect the rate of glycolysis have been explained. The commercial implications of electrical stimulation in the meat industry are highlighted giving special emphasis to hot-boning, energy conservation, and operator safety.

Abattoirs↗
PubMed1981

Effects of ad libitum, maintenance and sub-maintenance feeding and of compensatory growth on some biochemical properties of muscle from weanling rabbits.

Weanling male rabbits were fed either: 1) a complete diet ad libitum (control); 2) a maintenance diet; or 3) a sub-maintenance diet. After 20 days, half of each group was slaughtered and the remainder was placed on treatment 1 until they achieved the same body weights as the controls (about 30 more days), when they were also killed. Body organs, including livers, hearts, lungs and kidneys, were significantly reduced in weight by nutritional stress. Maintenance and sub-maintenance feeding resulted in creases in ultimate muscle pH, water content and alkali-soluble and -insoluble stromal proteins. The intracellular proteins, especially the myofibrillar fraction, decreased markedly, depending on the degree of nutritional stress. Swelling of the stromal proteins was less for the underfed rabbits, indicating that nutritional stress increased the number of acid-stable corss-linkages. Calcium-induced contraction was not effected by any of the nutritional treatments. Blood enzymes were not affected by nutritional stress from the standpoint of their multiple molecular forms, mobility or band profiles. All differences in muscle characteristics disappeared during compensatory growth except for the increased amount of alkali-insoluble stroma protein. The concepts of labile, mobilizable and fixed body proteins are discussed.

Animals↗
PubMed1978

The mechanism for the promotion of tenderness in meat during the post-mortem process: a review.

The post-mortem changes in the chemical composition and structure of striated muscle have been reviewed on the basis of various concepts that emerged from the studies of different investigators to explain the course of tenderization of meat during aging. These concepts include the changes in the sarcoplasmic proteins, myofibrillar proteins (such as complete dissociation of actomyosin, partial dissociation of actomyosin, cleavage of disulfide linkages, depolymerization of F-actin filaments, cleavage of myosin filaments, disorganization of Z-bands and the troponin-tropomyosin complex), sarcolemma, connective tissue elements (collagen fibrils, ground substance), and the protein-ion relationship of the muscle cells (more strictly, syncytia). The experimental evidence for and against each of the views is discussed critically in the light of certain fundamentals of biophysical chemistry and biochemistry. Finally, an alternative hypothesis has been presented based on the differential effect of the post-mortem formation of lactic acid (H+ ion concentration) on the intra- and extracellular components of muscle and the possible role of lysosomal cathepsins. Consequently, a series of biophysical, biochemical, and ultrastructural changes seem to account for the mechanism by which meat becomes tender during the aging process.

Actinin↗