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T Mustafa

Publications and source records attributed to T Mustafa.

At least 37 records · Page 2Linked to original sources
PubMed1999

Increased expression of Fas ligand on Mycobacterium tuberculosis infected macrophages: a potential novel mechanism of immune evasion by Mycobacterium tuberculosis?

We have studied the location and mechanism of apoptosis within the granulomas in the lungs at various stages of slowly progressive primary murine Mycobacterium tuberculosis infection. Parallel sections were analyzed for detection of mycobacterial antigens, Fas, and Fas ligand (FasL) by immunohistochemistry, and for apoptotic cells by terminal deoxynucleotidyl-transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) method. The frequency of apoptosis was high in the macrophage aggregates as compared to the lymphocyte aggregates and at the interface between them. Five to seven percent of the vacuolated macrophages in the granulomas expressed FasL intensely. These cells contained large amounts of mycobacterial antigens. These findings suggest that M. tuberculosis infection can induce increased expression of FasL in a population of infected macrophages. As a consequence the infected macrophages will be protected from the attack of cytotoxic T cells and activation of bactericidal mechanisms by Th1 type lymphocytes. This constitutes a novel evasion mechanism for M. tuberculosis possibly explaining the chronic course of infection.

Animals↗
PubMed1999

Changes in T-lymphocyte subsets in lungs and spleens of mice with slowly progressive primary mycobacterium tuberculosis infection: involvement of unconventional T-cell subsets.

Our previous study showed that the cell-activation responses and cytokine-secretion patterns were different in lungs and spleens of mice with slowly progressive primary Mycobacterium tuberculosis infection. The aim of the present study was to characterize the T-cell subsets in lungs and spleens of mice with a similar infection. The percentages of T-cell subsets were determined by flow cytometry and the absolute numbers were calculated. Spleens of infected mice showed a threefold expansion of CD4+ cells but no change in CD8+ cells, whereas lungs had a threefold increase of both subsets. A significant expansion of CD4-CD8-alphabeta+ [double negative (DN)alphabeta+] subsets was observed in the lungs of infected mice compared with uninfected mice. This was not the case in the spleens of infected mice. In infected mice the CD4-CD8- (DN) population preferentially expressed alphabeta-T-cell receptors (TCR) in the lungs but gammadelta-TCR in the spleens. The percentages of many T-cell subsets were significantly higher in the lungs than in the spleens of both uninfected and infected mice. However, the percentages of CD4+ and CD4-CD8+TCR- subsets in the lungs were significantly lower than in the spleens of infected mice. We also observed some previously unreported T-cell subsets: double positive-TCR- (DPTCR-), DPalphabeta+ and DPgammadelta+. So far their functions are unknown.

Animals↗
PubMed1999

A mouse model for slowly progressive primary tuberculosis.

The progression from primary Mycobacterium tuberculosis infection to disease is usually slow in humans. The aim of this study was to develop and characterize a mouse model for slowly progressive primary tuberculosis, using the intraperitoneal (i.p.) route of infection, and to compare it with our previously described model of latent M. tuberculosis infection. B6D2F1 hybrid mice inoculated with 1.5 x 106 colony-forming units (CFUs) of M. tuberculosis H37Rv were followed-up for 70 weeks. Lungs, livers and spleens were examined for bacillary growth, histopathological changes and mycobacterial antigens (MPT64, ManLAM and multiple antigens of M. tuberculosis), by immunohistochemical staining. The infection was found to pass through three distinctive phases. During phase 1, mice were healthy despite development of small granulomas and an increasing number of bacilli in the lungs. During phase 2, mice were unwell but mortality was low. The count of M. tuberculosis and the granuloma size stabilized. The granulomas contained an increasing population of large, vacuolated macrophages. During phase 3, mice became moribund and died rapidly, but the M. tuberculosis count remained relatively stable. The inflammatory infiltrates filled approximately 80% of the lung parenchyma and the lesions were not well demarcated. Rapidly progressing inflammation, rather than an increase in the M. tuberculosis count, seems to contribute more to mortality.

Animals↗
PubMed1999

Effect of raw versus boiled aqueous extract of garlic and onion on platelet aggregation.

The effects of aqueous extracts of raw and boiled garlic and onions were studied in vitro on the collagen-induced platelet aggregation using rabbit and human platelet-rich plasma. A dose dependant inhibition of rabbit platelet aggregation was observed with garlic. Onion also showed dose-dependent inhibitory effects on the collagen-induced platelet aggregation but this inhibition was of a lesser magnitude compared to garlic when related to dose. The concentration required for 50% inhibition of the platelet aggregation for garlic was calculated to be approximately 6.6 mg ml(-1) plasma, whereas the concentration for onion was 90 mg ml(-1) plasma. Boiled garlic and onion extracts showed a reduced inhibitory effect on platelet aggregation. Garlic but not onion significantly inhibits human platelet aggregation in a dose-dependent fashion. The potency of garlic in inhibiting the collagen-induced platelet aggregation is approximately similar to that of rabbit platelets (8.8 mg ml(-1) produced 50% inhibition of platelet aggregation). The results of this study show that garlic is about 13 times more potent than onion in inhibiting platelet aggregation and suggest that garlic and onion could be more potent inhibitors of blood platelet aggregation if consumed in raw than in cooked or boiled form.

Animals↗
PubMed1998

A mouse model for latent tuberculosis.

The aim of the study was to establish a reproducible murine model for latent tuberculosis. We propose an operational definition of latent murine tuberculosis as a stable Mycobacterium-tuberculosis count in lungs and spleens without clinical signs or obvious histopathological changes in the lungs over a long period of time and without spontaneous reactivation of disease. B6D2F1Bom mice were inoculated with a wide range of Mycobacterium tuberculosis doses intraperitoneally or intravenously and followed for a long period to determine suitable conditions to produce latent infection. No anti-tuberculosis drug treatment was used. Microbiological and histopathological studies were carried out. Corticosterone challenge was used to reactivate the latent infection. Mice infected with 4 x 10(4) and 4 x 10(5) bacilli i.p. were followed up to 107 weeks without spontaneous reactivation. The present model is discussed in comparison with previous latent tuberculosis mouse models as well as the possible mechanisms of shift to stationary phase from multiplying bacilli.

Animals↗
PubMed1998

Vasoactivity of adenosine in the trout (Oncorhynchus mykiss) coronary system: involvement of nitric oxide and interaction with noradrenaline

A vasoconstrictory response to adenosine has been reported in coronary rings from fish. Since the reactivity of the large coronary arteries and the microcirculation may differ, the present study was undertaken to determine the role of adenosine in the intact coronary system of trout under constant pressure or flow using an isolated and non-working heart preparation. The involvement of nitric oxide (NO) and the interaction with noradrenaline were also studied. At 10(-9) to 10(-8 )mol l-1, adenosine caused a vasoconstrictory response, whereas between 10(-7) and 10(-5 )mol l-1 the response was predominantly vasodilative. Theophylline abolished both these responses to adenosine. The vasodilation induced by adenosine (at 10(-5 )mol l-1) was significantly reduced when the preparation was perfused under constant-flow than rather under constant-pressure conditions. The nitric oxide synthase inhibitor N-nitro-l-arginine (l-NA, 10(-4 )mol l-1) partially reduced the vasodilation induced by adenosine (at 10(-5 )mol l-1) under constant-pressure but not under constant-flow conditions. Perfusion of the intact coronary system with l-arginine or with adenosine significantly increased the rate of nitrite (NO2-) release, while perfusion with l-NA or theophylline reduced NO2- release. Chemical denudation of the coronary endothelium by CHAPS resulted in the loss of both the l-arginine- and adenosine-mediated vasodilation and the l-arginine-induced increase in the rate of NO2- release. Adenosine (10(-5 )mol l-1) offset and overrode the vasoconstriction induced by 10(-7 )mol l-1 noradrenaline. l-NA inhibited only the adenosine-induced vasodilation but not the ability to offset noradrenaline vasoconstriction, excluding the involvement of NO in the interaction between adenosine and noradrenaline.

Journal Article↗
PubMed1996

Trends in mortality and health behaviors: status of white and African-American women.

A substantial proportion of mortality in the United States can be attributed to three major behaviors: using tobacco, maintaining an unhealthy diet, and being physically inactive. Using data from the South Carolina mortality files and Behavioral Risk Factor Surveillance System we were able to document state trends in mortality, cigarette smoking, physical inactivity, and unhealthy dietary practices. We found that, in spite of the declines in heart disease and stroke mortality noted nationally and in the state, the risk factor profiles for most women in South Carolina did not improve. This analysis further suggests that physical inactivity and dietary issues (excess caloric intake, low fruit and vegetable consumption) would be good choices for lifestyle interventions among women in South Carolina, not only because they ultimately affect mortality, but also because they exert interim effects on morbidity, including physical functioning and independence.

Black or African American↗
PubMed1995

The effects of medically-orientated labour ward routines on prefeeding behaviour and body temperature in newborn infants.

The effects of medically-orientated labour ward routines were studied during the the first hour after birth, in 48 vaginal, single deliveries. All infants were immediately separated from their mothers and left on a resuscitation table. There was no significant difference in onset of crying if the infant received cutaneous stimulation or not. It was found that 17 infants, not showing hand-to-mouth activity, were bathed at an average time of 17 min (12-23 min) after birth, while those who did were bathed at 28.5 (24.5-41.5) min (P = 0.002). One infant was breastfed during the first hour. Being separated from its mother, bathed early, and swaddled after birth seemed to interfere with the infant's inborn ability to signal hunger. Forty-one infants were hypothermic at 1 hour. According to a multiple regression analysis infant body temperature at 60 min of age corresponded positively with birth weight (P = 0.0001) and time of oxygen administration (P = 0.0002). A plausible explanation for the effect of oxygen exposure is that there is brown fat inactivation in normal newborn infants and administration of oxygen activates the brown fat. It might be advantageous to let the mother keep the baby warm, rather than manipulate the baby's metabolism with oxygen.

Birth Weight↗
PubMed1993

Escobar syndrome.

Explore the source record for details and available documents.

Abnormalities, Multiple↗
PubMed1992

Ginger (Zingiber officinale) in rheumatism and musculoskeletal disorders.

One of the features of inflammation is increased oxygenation of arachidonic acid which is metabolized by two enzymic pathways--the cyclooxygenase (CO) and the 5-lipoxygenase (5-LO)--leading to the production of prostaglandins and leukotrienes respectively. Amongst the CO products, PGE2 and amongst the 5-LO products, LTB4 are considered important mediators of inflammation. More than 200 potential drugs ranging from non-steroidal anti-inflammatory drugs, corticosteroids, gold salts, disease modifying anti-rheumatic drugs, methotrexate, cyclosporine are being tested. None of the drugs has been found safe; all are known to produce from mild to serious side-effects. Ginger is described in Ayurvedic and Tibb systems of medicine to be useful in inflammation and rheumatism. In all 56 patients (28 with rheumatoid arthritis, 18 with osteoarthritis and 10 with muscular discomfort) used powdered ginger against their afflictions. Amongst the arthritis patients more than three-quarters experienced, to varying degrees, relief in pain and swelling. All the patients with muscular discomfort experienced relief in pain. None of the patients reported adverse effects during the period of ginger consumption which ranged from 3 months to 2.5 years. It is suggested that at least one of the mechanisms by which ginger shows its ameliorative effects could be related to inhibition of prostaglandin and leukotriene biosynthesis, i.e. it works as a dual inhibitor of eicosanoid biosynthesis.

Aged↗
PubMed1990

Ginger (Zingiber officinale) in migraine headache.

Migraine is considered as a neurological disorder with little convincing evidence of the involvement of some vascular phenomenon. Recent understanding of the mechanisms behind migraine pain generation and perception have considerably helped the development of modern migraine drugs. Most migraine drugs in use, i.e., ergotamine and dihydroergotamine, iprazochrome, pizotifen and diazepam; and non-steroidal antiinflammatory drugs (i.e. aspirin, paracetamol, persantin, etc.) have side-effects and are prescribed with caution for a limited duration. Ginger is reported in Ayurvedic and Tibb systems of medicine to be useful in neurological disorders. It is proposed that administration of ginger may exert abortive and prophylactic effects in migraine headache without any side-effects.

Adult↗
PubMed1989

Ginger (Zingiber officinale) and rheumatic disorders.

Oxygenation of arachidonic acid is increased in inflamed tissues. In this condition products of two enzymic pathways--the cyclooxygenase and the 5-lipoxygenase producing respectively prostaglandins and leukotrienes--are elevated. Of the cyclooxygenase products, PGE2 and of the lipoxygenase products, LTB4 are the strongest candidates for mediating inflammation. Non-steroidal anti-inflammatory drugs which inhibit the cyclooxygenase, and corticosteroids are used to treat such disorders. Both types of drugs produce adverse side-effects on prolonged use. Ginger is reported in Ayurvedic and Tibb systems of medicine to be useful in rheumatic disorders. Seven patients suffering from such disorders reported relief in pain and associated symptoms on ginger administration.

Aged↗
PubMed1977

The phosphoenol-pyruvate branchpoint in adult Hymenolepis diminuta (Cestoda): a study of pyruvate kinase and phosphoenol-pyruvate carboxykinase.

The properties of pyruvate kinase (PK) and phosphoenol pyruvate carboxykinase (PEP CK), two enzymes that determine the preferrential accumulation of either succinate or lactate as endproducts of carbohydrate metabolism, are described in adult Hymenolepis diminuta. PK activity at Vmax and Km levels of PEP was unaffected by ATP, alanine, FDP4, OR H+ ions, but was inhibited by 50% at 6.3 mM L-lactate and 30 mM HCO3. The addition of 30 mM HCO3 increased the Km(PEP) by 6-fold but did not alter the Vmax. The inhibition of PK by HCO3 cannot be explained entirely by an effect of ionic strength, but probably represents a specific modulator-enzyme interaction. Under similar conditions PEP CK was maximally activated. Although L-lactate inhibited PEP CK (Ki(lac) = 1.8 mM), this effector may play a minor role in regulation of PEP flux. These results implicate the poise of the HCO3-:CO2 system as a major determiner of endproduct accumulation in H. diminuta.

Animals↗