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Biomedical subjects

M A Ali

Publications and source records attributed to M A Ali.

At least 253 records · Page 14Linked to original sources
PubMed1977

Effect of lead on globin synthesis in vitro.

A defect in heme synthesis is well documented to occur in lead intoxication. Globin synthesis and the alpha/beta globin chain synthesis ratio have been shown to be disturbed in lead poisoning. To elucidate further the nature of the inhibitory effect of lead on hemoglobin synthesis, reticulocyte-rich peripheral blood samples have been incubated with lead at concentrations of 10(-6), 10(-5), and 10(-4) M, equivalent to 20, 200, and 2,000 mug/dl (.96, 9.6 and 96.0 mumol/l), respectively. The incorporation of tritiated leucine into globin was determined. Globin chain synthesis decreased to 85, 49 and 15% of the control value with increasing lead concentrations. The effect of heme on inhibition of globin synthesis by lead was studied by incubating reticulocyte-enriched blood with lead 10(-5) M (200 mug/dl; 9.6 mumol/l) in the presence or absence of heme at a concentration of 10(-3) M. Lead alone depressed the incorporation of tritiated leucine to 45% of control, while globin synthesis with heme alone was 109% of control. Although in the presence of both heme and lead, the mean incorporation of leucine into globin was 69.2% of control, the increase was not significantly different from that obtained with lead alone. It is concluded that (1) lead has an inhibitory effect on globin synthesis at a concentration considered to be within the acceptable range encountered in environmental lead pollution, and the extent of inhibition is dose-dependent; (2) the effect of lead on globin synthesis is not significantly prevented by heme and, therefore, does not appear to be mediated through the well-documented inhibitory effect of lead on heme synthesis.

Dose-Response Relationship, Drug↗
PubMed1977

Subacute staphylococcal meningitis secondary to postpartum endometritis.

A woman with Staphylococcus aureus meningitis following postpartum endometritis presented with lumbar backache and fever of several weeks' duration. Thick, green exudate was aspirated at lumbar puncture hours before death. Histologic examination demonstrated subacute inflammation of the meninges and chronic inflammation of the endometrium. Although rare, postpartum endometritis followed by low back pain and fever should alter the physician to the possibility of serious infection involving the central nervous system. Diagnosis and treatment at this early stage would be expected to decrease mortality.

Adult↗
PubMed1977

Diagnosis of intravascular haemolysis using starch gel electrophoresis.

Starch gel electrophoresis was used to screen for intravascular haemolysis in 15 patients with clinical disorders known to be characterized by intravascular haemolysis. Decreased serum haptoglobins, increased free plasma haemoglobin and the presence of methaemalbumin was documented in all 15 patients. It is suggested that starch gel electrophoresis and staining with haem specific stain is a simple and reliable method for confirming intravascular haemolysis.

Anemia, Hemolytic↗
PubMed1977

Retinal structure in Synbranchus marmoratus with observations on two new cone myoid inclusions.

The retina of a South American swamp eel, Synbranchus marmoratus (Synbranchidae), was studied by Golgi impregnation, light and electron microscopy. Its principal features include (1) the presence of a dense matrix, possibly a new type of tapetum lucidum, in the pigment epithelium, (2) a well developed photoreceptor layer containing large rods, single, double and triple cones, and (3) well developped inner nuclear and plexiform layers, with the exception of horizontal cells which are few and relatively small. These and other observations are discussed in relation to the photic environment and habits of this fish. The presence of microfilament bundles and two unusual features, microtubuleladen dense bodies and paracrystalline inclusions, in cone myoids are discussed in terms of their possible involvement in retinomotor responses.

Animals↗
PubMed1977

Value of serum copper measurement in acute leukaemia of childhood.

Serum copper level (SCL) determination was carried out on sixteen normal children and on 16 with acute leukaemia. A significant increase in SCL was observed in cases of leukaemia than in normal controls. Drop of SCL occurs in cases who respond to quadruple chemotherapy, while those who failed to respond showed persistantly high serum copper level.

Acute Disease↗
PubMed1976

Hemoglobin Bethesda, beta 145 (HC2) Tyr replaced by His, in a Canadian family.

A hemoglobin mutant with the mobility of hemoglobin (Hb) A on alkaline cellulose acetate or starch gel electrophoresis and mobility between Hb A and Hb S on citrate agar electrophoresis was detected in a patient with erythrocytosis. Structural analysis shows a substitution of histidine by tyrosine at position 145 in the beta-chain.

Adult↗
PubMed1976

Some bacteriologic aspects of the epidemiology of pulmonary and extrapulmonary tuberculosis.

A study was carried out to investigate the drug resistance patterns of the prevalent tubercle bacilli in pulmonary and extrapulmonary tuberculosis in and about the city of Lahore, Pakistan. This report includes 168 strains of Mycobacterium tuberculosis isolated from the same number of pulmonary tuberculosis cases (100 untreated cases, defined as patients either having no history of anti-tuberculous therapy or having had chemotherapy for not more than 10 days; 68 treated, defined as having had chemotherapy for more than 10 days), and 162 strains from the same number of extrapulmonary tuberculosis cases (77 untreated, 38 treated and 47 doubtful). The proportion method of drug susceptibility assay was employed. According to the procedures used in this study and with 1% as the critical proportion for resistance, bacterial resistance was found to be very prevalent in pulmonary tuberculosis. Even among those cases in which no history of previous treatment was elicited, 46% were found to be excreting populations of tubercle bacilli having some degree of resistance to one or more of the primary drugs--isoniazid, streptomycin and para-aminosalicylic acid. In treated cases, 86.8% were found to have some resistance to one or more drugs. Overall, resistance to streptomycin was found to be commonest. Drug resistance was observed to be somewhat less common in extrapulmonary than in pulmonary tuberculosis, with streptomycin resistance predominating. Although both catalase-positive and catalase-negative isoniazid-resistant strains of M. tuberculosis were isolated from patients with pulmonary disease, no catalase-negative strains were isolated from patients with extrapulmonary disease, suggesting limited pathogenic potentialities of catalase-negative strains for man. Epidemiologic aspects of these observations are discussed.

Adult↗
PubMed1976

Scanning electron microscopy of four teleostean retinas.

The morphology of the retinas of the goldeye Hiodon alosoides (fam. Hiodontidae), the brook trout Salvelinus fontinalis (fam. Salmonidae), the yellow perch Perca flavescens and the walleye Stizostedion vitreum (fam. Percidae) was studied by SEM. Semi-thin plastic sections of the same retinas were also examined for comparison. Contrary to observation of earlier authors the goldeye retina was found to possess both rods and cones; in the case of the other three fishes' retinas, present observations correspond to previous ones, adding only details. SEM gives an impressive, three dimensil view of the gross surface features of the retinas. Shrinkage during the processing of the specimens for SEM, while not altering the general topography, does induce artifacts in both plexiform layers.

Animals↗
PubMed1976

Acute idiopathic polyneuritis caused by cytomegalovirus.

Cytomegalovirus was isolated from the PBBC from a patient with acute idiopathic polyneuritis. Viremia occurred during the early phase of the neurologic disease, preceding viruria, and was accompanied by specific CMV-IgM antibodies, which indicates a recently acquired infection. Complement fixing antibodies to CMV remained stable throughout the illness at a relatively low titer. Previously, CMV has been associated with acute idiopathic polyneuritis on the indirect evidence of rising or elevated titers of complement fixing antibodies or isolation of virus from urine or saliva or both. Our findings provide direct evidence for the causative role of CMV in acute idiopathic polyneuritis.

Acute Disease↗
PubMed1976

[Role of the epiphysis in the migration of retinal epithelial pigment during unilateral photic stimulation in Salmo irideus].

Unilateral exposure of dark-adapted fishes indicates that the exposed eye is only partly in a light-adapted state in so far as the position of the epithelial pigment and cones is concerned. This does not occur in epiphysectomized fishes indicating a possible role of the epiphysis. On the basis of available evidence, the nature of the epiphysis role is envisaged and a suggestion made that melatonin, whose synthesis is related to dark, may play a role in this phenomenon.

Animals↗
PubMed1975

Hemoglobinopathies in the Hamilton region. II. Thalassemia traits and iron therapy.

Between July 1973 and July 1974 all adult patients with hypochromic anemia and a mean corpuscular volume of 75 mum3 or less were screened for hemoglobinopathies. Of the 490 patients 105 had beta-thalassemia trait, 11 had alpha1-thalassemia trait, 4 had hemoglobin Lepore trait and 1 had hemoglobin H disease. Of 48 inpatients whose charts were reviewed 19 had been on oral iron therapy and 7 of them had been given iron intramuscularly. Of 27 outpatients interviewed 10 had been on intermittent iron therapy for 18 months or more; 4 had been given at least 1 g of intramuscular iron. Iron deficiency was not documented in any of these patients. Iron deficiency should be diagnosed by means other than the presence of a hypochromic picture in the peripheral blood before iron therapy is instituted, particularly in communities with a large population of Mediterranean or South-East Asian origin.

Administration, Oral↗
PubMed1975

Hemoglobinopathies in the Hamilton region. I. A 4-year survey.

A regional laboratory for the diagnosis and investigation of hemoglobinopathies was established by the Hamilton District Program in Laboratory Medicine in October 1970. Specimens from patients suspected of having a hemoglobinopathy were referred to the regional laboratory from all the hospitals participating in the program. Between October 1970 and October 1974, 3547 specimens were screened for an abnormal hemoglobin and thalassemia; 758 cases of thalassemia, 165 cases of abnormal hemoglobin and 14 mixed cases were diagnosed. Before 1970, 110 cases of thalassemia and 12 cases of abnormal hemoglobin were on record in the Hamilton region. Regionalization of laboratory services provides a more effective means of screening for abnormalities in hemoglobin structure and synthesis and facilitates the opportunity for improving diagnostic procedures.

Asia, Southeastern↗
PubMed1975

Hemoglobin A2 level. A proposed test for confirming the diagnosis of iron deficiency.

The absolute hemoglobin A2 concentration in mg. per 100 ml. of blood was calculated from the hemoglobin level in Gm. per 100 ml. and hemoglobin A2 percentage for 38 patients with documented iron deficiency, 37 patients with proven beta-thalassemia minor, 26 patients with simple chronic anemia and 40 normal control laboratory workers. The mean hemoglobin A2 concentration (mg. per 100 ml.) in the control group was 459 plus or minus 60 (2 S.D.) and that in the beta-thalassemia group, 766 plus or minus 99. However, in the iron deficiency group it was 229 plus or minus 58, while in the simple chronic anemia group it was 315 plus or minus 39. The mean corpuscular volume (M.C.V.) in cu. mu was 90 plus or minus 8 (2 S.D.) in the normal controls, 68 plus or minus 10 in beta-thalassemia, 69 plus or minus 9 in iron deficiency, and 90 plus or minus 15 in secondary anemia. It is proposed that the absolute hemoglobin A2 level in mg. per 100 ml. of blood taken in conjunction with the M.C.V. is of value in establishing the diagnosis of iron deficiency.

Anemia↗
PubMed1975

Temperature and vision.

Published information concerning the influence of temperature in the physiological range (0-40 degrees) on various aspects of the visual process in invertebrates and vertebrates (poikilotherms and homeotherms) is reviewed. Bleaching and regeneration of scotopic and photopic pigments is influenced by temperature; so is the porphyropsin-rhodopsin ratio in fresh-water fishes. Effect on electrophysiological responses such as early receptor potential (ERP), electroretinogram (ERG) and its flicker fusion frequencies (FFF), S-potentials, glial membrane optic nerve and brain responses is presented. Histophysiological responses such as photomechanical or retinomotor responses are influenced by temperature. It also affects behavioural responses such as innate light reflexes, colour change, sensitivity, threshold acuity, FFF, spectral sensitivity and conditioned responses. General aspects such as oxygen consumption of the retina, acid formation and survival times are discussed with reference to their modification by temperature. Theoretical aspects such as the interaction between light and thermal energy in the absorption of a photon by a molecule, and available equations for comparing the effect of temperature on biological processes are also discussed. An attempt is made to draw a coherent picture and to discuss the significance of the thermal influence on vision to the animal. New avenues of research are also indicated. One hundred and eighty-eight (188) references are cited.

Animals↗