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Biomedical subjects

S Islam

Publications and source records attributed to S Islam.

At least 145 records · Page 8Linked to original sources
PubMed1975

Interaction between the activity of an epileptic focus and discrete skilled movements in rats.

Sixteen male hooded rats were trained to reach into a narrow feeding tube for small food pellets. The paw movements were photoelectrically detected. An epileptic focus established by local application of 1% picrotoxin on the exposed motor cortex increased the frequency of reaching with the ipsilateral paw and impaired reaching with the contralateral paw. Interictal discharge rate of all ipsilateral foci was increased by reaching in the same way as the slow activity (less than 0.5/sec) of contralateral foci. On the other hand, fast activity (greater than 0.5/sec) of contralateral foci was decreased by reaching. Computer analysis of interictal discharge indicence during 512 msec before and after reaching onset showed that the brief facilitation of discharge (50 msec) during the actual movement was often preceded and followed by more prolonged inhibition (200 msec). The inhibition was better expressed in the contralateral hemisphere. The results are interpreted as due to changes of cortical excitability associated with reaching and to interference of the epileptic focus with the cortical elaboration of the skilled movement.

Action Potentials↗
PubMed1975

Interhemispheric transfer of extinction of the active avoidance reaction in rats.

Cortical spreading depression (CSD) was employed in rats to study the lateralization of extinction of a jumping avoidance reaction. Under unilateral CSD, 181 nonreinforced trials were needed to extinguish the avoidance reaction acquired in three 100-trial sessions of intact-brain training. During a second extinction session, either with the same or with the contralateral hemisphere depressed, the mean number of trials to the extinction criterion (9/10) was 39 (n = 12) or 186 (n = 15), respectively. Five extinction trials performed with the brain intact 1 hr before extinction with contralateral CSD decreased the number of trials to extinction of 98 (n = 11). Thus, extinction of active avoidance can be lateralized and interhemispherically transferred in the same way as acquisition of this habit.

Animals↗
PubMed1975

Epidemiologic investigation of an outbreak of Shiga bacillus dysentery in an island population.

An epidemic of dysentery broke out in St. Martin island during May through July 1973. The epidemic was caused by Shigella dysenteriae type 1. The dysentery could not be controlled by conventional antibiotics and other antidysenteric drugs. The average attack rate was 32.9%. The age specific attack rate was highest in the age group 1-4 years (52.2%). The attack rates were higher in smaller families. The rates were not greatly different amongst people using different sources of water. The overall death rate was 2.1%. The overall infection-to-death rate was 6.4% but amongst children less than a year old, it was 41.1%. A common source outbreak was unlikely. The higher attack rate in smaller families suggested limited possibility of person to person spread. No particular water source could be implicated with higher attack rate. Flies may have played an active role in transmission.

Adolescent↗
PubMed1975

The effect of cortical spreading depression on motor performance and depth avoidance in rats.

Functional decortication induced by cortical spreading depression (CSD) was used to estimate the significance of cerebral cortex for swimming and depth avoidance in arts. In the swimming test (5 gr sinkers, 36 degrees C water) the median swimming time was reduced from greater 120 minutes in the controls to 16 minutes in the bilaterally depressed rats. Depth avoidance in the physical and visual cliff situation (6 cm to the shallow and 48 cm to the deep surface) was unimpaired by unilateral CSF but was abolished by bilateral CSD. Combination of monocular occlusion with ipsilateral CSD deteriorated the visual cliff test but not the physical cliff behaviour. Functional decortication increased descent latencies and decreased the explaration rate in both tests. It is concluded that cerebral cortex plays an important role in the regulation of unlearned, innate activities with the overall behaviour of the organism.

Animals↗
PubMedDate not supplied

Drug-induced hepatitis associated with anticytoplasmic organelle autoantibodies.

A study from five hepatology units documenting 157 cases of drug-induced hepatitis and a second study from a laboratory of immunology which tested more than 100,000 sera permitted us to establish the frequency of antiorganelle antibodies and their diagnostic value in drug-induced hepatitis. In drug-induced hepatitis caused by a heterogenous group of drugs consisting of ajmaline, aminopterine, isaxonine, isoniazid, perhexiline, phenylbutazone and troleandromycine, antiorganelle antibodies were absent or rare. In drug-induced hepatitis caused by another heterogenous group of drugs, including clometacin, fenofibrate, oxyphenisatin and papaverine, antismooth muscle, antinucleus and antimitochondria antibodies were found in isolation or in different combinations in 70% of cases. From the presence of antismooth muscle antibodies in sera, we could trace 30 cases of clometacin-induced hepatitis. The third group included drug-induced hepatitis with special antibody:iproniazid-induced hepatitis with antimitochondrial antibody 6 and tienilic acid (ticrynafen)-induced hepatitis with antiliver/kidney microsome antibody 2 (anti-LKM2). These two antibodies are rare in routine sera and were absent in patients who received the drug and had no liver damage. From the presence of corresponding antibodies, we detected six cases of iproniazid-induced hepatitis and 67 cases of tienilic acid-induced hepatitis. Antiorganelle antibodies found in high titers disappeared in 2 to 24 months following withdrawal of the offending drug. The fourth group was represented by halothane-induced hepatitis; antiliver/kidney microsome antibody 1 was weak and infrequent. Similarities between drug-induced hepatitis of the second group and lupoïd hepatitis suggest that drugs may reveal this spontaneous disorder.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Chronic active hepatitis associated with antiliver/kidney microsome antibody type 1: a second type of "autoimmune" hepatitis.

Sixty-five patients with histologically proven chronic active hepatitis of unknown cause but associated with the antiliver/kidney microsome antibody type 1, confirmed by immunofluorescence and immunoprecipitation, were selected as forming a special entity. This disease was found to be rare with a prevalence of 5/1,000,000. The female to male ratio was 8:1. The condition occurred at all ages but was most common between the ages of 2 and 14 years. In 22 of the 65 cases, the hepatitis was associated with an autoimmune disease, most commonly insulin-dependent diabetes, autoimmune thyroid disease and vitiligo. The same autoimmune diseases were present in first-degree relatives from seven families. In 36 cases, the onset of disease resembled acute viral hepatitis. Serum biochemical tests showed marked elevation in aminotransaminases and hypergammaglobulinemia. Paradoxically, serum and salivary IgA levels were often normal or low. Histologic findings were multifocal hepatic necrosis with bridging in the acute stage, and aggressive hepatitis with mononuclear cell infiltration or macronodular cirrhosis in the late stages. Serologically, apart from the presence of antiliver/kidney microsome antibody type 1, the disease was characterized by the absence of antiactin, antimitochondria and antinucleus antibodies; however, organ-specific autoantibodies were often present. The clinical course was usually severe: six patients in the acute stage presented with fulminant hepatitis, and all, except two, other patients progressed to cirrhosis. Prolonged treatment with corticosteroids and immunosuppressants was usually effective in rendering the cirrhosis inactive. The cumulative survival rate was 51% at 14 years. We propose to call this entity "anti-LKM1 chronic active hepatitis" or "autoimmune hepatitis type II" to differentiate it from classical "lupoid hepatitis" or autoimmune hepatitis type I.

Autoantibodies↗
PubMedDate not supplied

Determinants of endothelium-dependent femoral artery vasodilation in youth.

OBJECTIVE: Decreased endothelium-dependent arterial dilation to reactive hyperemia has been shown in adults to be associated with various manifestations of cardiovascular diseases and cardiovascular risk factors. In a sample of children, we examined the relationships between flow-mediated femoral artery dilation and anthropometric, demographic, cardiovascular, and serum lipid variables that have been associated with cardiovascular diseases. METHOD: Thirty-three asymptomatic, healthy 11 to 14 years olds were randomly selected from participants in a longitudinal cardiovascular health study. There were 17 boys and 16 girls; 21 whites and 12 blacks. Sixteen had documented family history of premature myocardial infarction (ie, < or = 55 years of age) in first-degree relatives and 17 did not. Measurements included fasting lipids, anthropometrics, blood pressure and heart rate at rest and during supine exercise, postural change, and forehead cold stimulation. Femoral artery dilation to reactive hyperemia was measured via high resolution ultrasound. RESULTS: Bivariate analyses indicated flow-mediated dilation was negatively correlated with systolic pressure increases to postural change, forehead cold stimulation and dynamic exercise, greater average skinfold thickness, and body fat via dual x-ray absorptiometry and positively correlated with cardiovascular fitness (all ps < .05). Stepwise multiple regression revealed that cardiovascular fitness and systolic pressure reactivity to exercise significantly predicted flow-mediated dilation accounting for 31% of the variance (p < .01). CONCLUSIONS: Decreased flow-mediated dilation is associated with decreased cardiovascular fitness, increased systolic pressure reactivity to various stressors, and increased indices of body fatness in asymptomatic youth. Further research is warranted to better understand early relationships between this noninvasive measure of endothelial function and cardiovascular risk factors in youth.

Adolescent↗
PubMedDate not supplied

Predicting violence: nursing diagnosis versus psychiatric diagnosis.

Predicting violent behavior is a major concern for nurses as well as other mental health professionals. Two diagnostic assessment systems (Nursing Diagnosis-NANDA and Psychiatric Diagnosis-DSM III-R) were compared in their ability to predict assaultive behavior. The nursing diagnosis potential for violence suggested a difference (p = .07) between the assaultive and control subjects. No differences were found between assaultive and control subjects on psychiatric diagnoses. Nursing diagnosis is based upon measurable behaviors and is time specific. Clinical implications and further research endeavors in this area are suggested.

Case-Control Studies↗
PubMedDate not supplied

Effects of tropisetron, a 5-hydroxytryptamine type 3 receptor blocker, on intestinal secretion induced by cholera toxin or deoxycholic acid in rabbits in vivo.

It has been suggested that 5-hydroxytryptamine is involved in the pathogenesis of various intestinal hypersecretory states including cholera. In this study, the effect of tropisetron (ICS 205-930), a specific 5-hydroxytryptamine type-3 receptor blocker, on jejunal and colonic fluid secretion induced respectively by cholera toxin and deoxycholic acid was investigated in rabbits using isolated loops of intestine in vivo. Marked fluid accumulation in both the jejunal and colonic loops was observed after exposure to cholera toxin and deoxycholic acid respectively. Elevation of jejunal and colonic mucosal cyclic adenosine monophosphate concentrations was also noted. Intraperitoneal administration of tropisetron dose-dependent inhibited jejunal secretion induced by cholera toxin. In contrast, no significant anti-secretory effect of tropisetron was observed against colonic secretion induced by deoxycholic acid. Tropisetron did not affect elevated mucosal cyclic adenosine monophosphate concentrations. The inhibitory effect of tropisetron on intestinal secretion induced by cholera toxin, which was independent of cyclic adenosine monophosphate formation, suggests that 5-hydroxytryptamine plays an important role in this type of secretion.

Animals↗
PubMedDate not supplied

Iron absorption after single pharmacological oral iron loading test in patients on chronic peritoneal dialysis and in healthy volunteers.

OBJECTIVE: Oral iron is poorly absorbed in chronic dialysis patients. We tested the hypothesis that a superpharmacologic dose of iron sulfate (260 mg elemental iron) administered on an empty stomach results in significant iron absorption in these patients. DESIGN: A prospective open controlled trial. SETTING: Outpatient department of a university hospital. PATIENTS: Nine stable chronic peritoneal dialysis (PD) patients and seven normal control subjects. METHOD: All subjects ingested a single dose of 4 tablets of iron sulfate (260 mg elemental iron total) in the morning while fasting. OUTCOME MEASURES: Serum iron concentrations at baseline, and at 2 and 4 hours after the oral dose were compared between the two groups. RESULTS: The control group showed a significant rise in mean [standard error (SE)] serum iron concentration, from a baseline value of 76.5 +/- 7 microg/dL to 191 +/- 10.5 microg/dL at 2 hours and to 190 +/- 24 microg/dL at 4 hours. This result represents a percentage rise of 164% +/- 32% at 2 hours and 152% +/- 28.5% at 4 hours. In the PD patients, a significant rise in serum iron concentration was also seen, from a baseline value of 64 +/- 8 microg/dL to 130 +/- 3 microg/dL at 2 hours and 111 +/- 18 microg/dL at 4 hours. This result represents a percentage rise of 105% = 29% at 2 hours and 77% +/- 23.5% at 4 hours. However, the absolute change in serum iron concentration in PD patients at 2 and 4 hours was approximately equal to 50% of the change in control subjects at those time points. None of the PD patients experienced gastrointestinal side effects; 4 control subjects experienced mild side effects. CONCLUSION: Despite impaired oral iron absorption in chronic dialysis patients, a large pharmacologic dose given orally can result in significant iron absorption and may prove to be a more efficient means of oral iron supplementation therapy in these patients.

Absorption↗
PubMedDate not supplied

Coronary Artery Risk Detection in Appalachian Communities (CARDIAC): preliminary findings.

West Virginia's mortality and morbidity from cardiovascular disease (CVD) is among the highest in the developed world. Appalachia, and West Virginia in particular, could reduce the high prevalence of premature coronary heart disease (CHD) by addressing modifiable independent risk factors such as poor nutrition, sedentary lifestyle, and tobacco use. School-based health promotion programs have been shown to be an effective means of influencing student and parental health behavior. The pilot phase of the Coronary Artery Risk Detection in Appalachian Communities (CARDIAC) project substantiated an alarmingly high incidence of CVD risk factors among 347 fifth grade children from three rural counties, and was also an effective means of identifying parents at risk of developing CHD. Utilization of the innovative Rural Health Education Partnerships (WVRHEP), coupled with a health conscious public school system, offers a unique opportunity to establish the first statewide cardiovascular disease community intervention project in the nation.

Blood Pressure Determination↗