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Biomedical subjects

M Ali

Publications and source records attributed to M Ali.

At least 253 records · Page 14Linked to original sources
PubMed1992

Severe heart muscle degeneration caused by Clostridium perfringens type A in camel calves (Camelus dromedarius).

Clostridium perfringens type A was isolated from different organs and intestines from three to five weeks old camel calves which have died from heart muscle necrosis. No other bacterial pathogens were isolated. Virus isolation on two different cell lines including a fetal camel skin were also negative. Mice which were injected with bacteria free filtrates prepared from intestinal contents of necropsied camel calves died after one to six hours demonstrating the presence of clostridial toxins. Our findings suggest that the cardiac muscle necrosis is caused by Clostridium perfringens type A toxins.

Animals↗
PubMed1992

The clinical significance of hemoglobinopathies in the Hamilton region: a twenty-year review.

Between 1970-1990, the Laboratory tested 38,391 specimens for hemoglobinopathies, of which 7,935 were positive. The major abnormalities detected were beta thalassemia trait (4,688), alpha thalassemia trait (1,248) and sickle cell trait (847). Clinically significant hemoglobinopathies detected were Hemoglobin H disease (100), sickle cell disease (67) and sickle cell Hemoglobin C disease (79). Hemoglobinopathies are therefore common in the Hamilton area as a reflection of the cultural diversity of area citizens. Of the 49 patients with thalassemia without documented iron deficiency, 8 (16%) received iron therapy for a variable period of time and 3 were investigated for gastrointestinal blood loss. Hemoglobin abnormalities cause or have the potential to cause clinical disease and they can, if not detected, result in unnecessary iron therapy or gastrointestinal investigation.

Hemoglobin C Disease↗
PubMed1992

Vanadate treatment increases the activity of glycolytic enzymes and raises fructose 2,6-bisphosphate concentration in hearts from diabetic rats.

The present study examined the effect of vanadate on the activity of key enzymes of glycolysis and the level of fructose 2,6-bisphosphate (F-2, 6-P2) in the hearts of diabetic rats. A 20% decrease in the total hexokinase activity and 66% decrease in the type II isoenzyme was found in diabetic rat hearts. Vanadate treatment doubled the activity of type II hexokinase. Pyruvate kinase and phosphofructokinase 1 activity was reduced by 20% in diabetes, vanadate treatment restored the activity of the enzymes to normal. A 43% decrease in the cardiac F-2, 6-P2 level was found in diabetes of four weeks duration. A significant inverse correlation between blood glucose of experimental animals and the level of heart F-2, 6-P2 was observed. Vanadate treatment doubled the amount of F-2, 6-P2 in diabetic rat hearts.

Animals↗
PubMed1992

A radiation resistance factor in cultured Cloudman S91 mouse melanoma cells.

The gamma-ray survival of a radiation-sensitive amelanotic subclone of Cloudman S91 mouse melanoma, S91/amel, is increased by the presence in the tissue culture dishes of heavily irradiated cells from the same cell line (amel-HRCells) and from clonally related melanotic S91/I3 radioresistant cells (I3-HRCells). The D0 of the target S91/amel cells increases from 1.25 to 2.08 Gy in the presence of 60,000 heavily irradiated S91/amel cells per dish. The presence of I3-HRCells in dishes of target S91/I3 cells does not increase their radioresistance. Comparable numbers of I3-HRCells are more effective than amel-HRCells at increasing survival of target S91/amel cells irradiated with 3 Gy of gamma rays. Conditioned medium from the S91 melanoma cells also increases the radioresistance of S91/amel, but is not as effective as the HRCells. Unirradiated cells can condition the medium as effectively as irradiated cells. It is concluded that the radiosensitive mouse melanoma cell line is made significantly more resistant by a diffusible cellular factor(s) elaborated more proficiently by radiation-resistant cells.

Animals↗
PubMed1991

Measurement of urokinase-type plasminogen activator activity in sera of nasopharyngeal carcinoma patients by an immunocapture assay.

The urokinase-type plasminogen activator (uPA) activity in sera of patients suffering from nasopharyngeal carcinoma was examined by a uPA-specific immunocapture assay. The results revealed that the activity levels in the patient sera were significantly higher than that of normal healthy controls. The uPA activity also increased with the staging of the disease and the anti-EBV VCA IgA titre which is a diagnostic test for the disease, although the results were not statistically different. These findings showed that the levels of the enzyme were related to the spread of the disease. In addition, it was demonstrated that the sensitivity of the assay could be increased by using SDS. If the sera were treated with 0.2% sodium dodecyl sulphate (SDS) prior to the assay, higher levels of measureable PA activity were detected.

Antigens, Viral↗
PubMed1991

Complementation by two non-homologous recombinant chromosomes 3.

The first example known to us of complementation by two non-homologous chromosomes 3 is present in the karyotype of a phenotypically normal brother of an inv(3)(p25q21) carrier. The normal chromosomes 3 are replaced by two complementary recombinant chromosomes 3. The longer recombinant duplicates 3q21-qter and is deficient for 3p25-pter. It is identical to the recombinant inherited by infants born with multiple congenital anomalies to inv(3)(p25q21) carriers. The shorter recombinant duplicates 3p25-pter and is deficient for 3q21-qter. This recombinant has previously been observed only in prometaphase spreads from sperm of an inv(3) carrier from the same kindred. Theoretically it is possible for the carrier of these complementary recombinant chromosomes 3 to produce sperm carrying either a normal 3, or the inversion 3, which could then fertilize an egg carrying a normal 3 followed by normal fetal development. However, the spouse of our propositus reported one first trimester spontaneous abortion, followed by no recognized pregnancy over the next 12 years of marriage.

Chromosome Inversion↗
PubMed1991

Iron deficiency anemia in the elderly: the diagnostic process.

OBJECTIVE: To determine the effectiveness of physician probability estimates calculated on the basis of findings from history-taking and physical examination in the diagnosis of iron deficiency anemia in elderly patients. DESIGN: Prospective study. SETTING: Two community hospitals offering secondary and tertiary care. PATIENTS: A total of 259 patients over 65 years of age found to have previously undiagnosed anemia. MEASURES: Physician estimates of the likelihood of iron deficiency before (pretest probability) and after (post-test probability) the laboratory test results were available. The hemogram was available to the physicians when they made their pretest probability estimates. Because the serum ferritin level proved to be the most powerful of the laboratory test results studied, the likelihood ratios associated with the post-test estimates were compared with the ratios associated with the serum ferritin level. MAIN RESULTS: The post-test probability estimates were influenced by the serum ferritin level and the pretest estimates. The post-test estimates derived from the findings obtained through history-taking and physical examination and the laboratory test results (including the serum ferritin level) were slightly less accurate in predicting iron deficiency than the serum ferritin level alone. Nevertheless, a model in which the pretest estimates were used in addition to the serum ferritin level to predict iron deficiency proved to be more powerful than the serum ferritin level alone (p = 0.006). This indicated that the limitations of the post-test estimates were due to a misinterpretation of the serum ferritin level and that the findings from history-taking and physical examination added important diagnostic information. CONCLUSIONS: Physicians must be aware of test properties to provide optimal care to their patients. If test results are properly interpreted, pretest probabilities derived from findings obtained through history-taking and physical examination can add useful information that will lead to more accurate diagnoses.

Aged↗
PubMed1991

Depletion of rat liver glucocorticoid receptor hormone-binding and its mRNA in sepsis.

Glucocorticoid receptor (GR) hormone-binding activity, its physical characteristics, and GR mRNA levels were studied in the liver, brain and muscle of normal (saline-injected) and hypermetabolic septic rats 24 h after the subcutaneous injections of E. coli. The GR levels (hormone-binding activity) declined by about 40%, 56%, and 40% in septic liver, brain, and muscle cytosol, respectively. The mechanism of the decrease in the GR levels in sepsis was studied in liver. The GR levels remained low (45% of control hormone-binding) even after 48 h of E. coli administration. The decrease in the liver GR occurred in the 9S untransformed GR. The 9S GR from septic liver transformed to the 4S form in proportions comparable to the control liver GR. In addition, the 4S GR from control and septic liver was capable of binding to DNA-cellulose to a similar extent. The GR mRNA level in septic liver declined by about 30%. Thus, a decrease in GR hormone-binding activity in sepsis appears to be due to a decline in the steady-state GR mRNA level and not from a change in the qualitative properties of the GR protein.

Animals↗
PubMed1991

Collagen toxicity in rabbits.

Different preparations of soluble collagen, from rabbit skin, rat skin, rat tail tendon and guinea-pig skin, produced respiratory distress, agitation, convulsions and finally death when infused intravenously in lethal doses. Analysis of plasma enzyme levels indicated significant increases in total, cardiac and hepatic lactate dehydrogenase, suggesting that damage to the liver occurred as a result of collagen infusion. Histopathological examination of lungs, livers and hearts of collagen-treated rabbits confirmed that damage had occurred to the lungs and livers of these animals, while heart tissues appeared to be normal. The source of collagen did not appear to influence its toxicity at the tissue level.

Alanine Transaminase↗
PubMed1991

Pyrimidine nucleotide synthesis in the rat kidney in early diabetes.

Early renal hypertrophy of diabetes is associated with increases in the tissue content of RNA, DNA, and sugar nucleotides involved in the formation of carbohydrate-containing macromolecules. We have previously reported an increase in the activity of enzymes of the de novo and salvage pathways of purine synthesis in early diabetes; the present communication explores the changes in the pathways of pyrimidine synthesis. Measurements have been made of key enzymes of the de novo and salvage pathways at 3, 5, and 14 days after induction of diabetes with streptozotocin (STZ), phosphoribosyl pyrophosphate (PPRibP), and some purine and pyrimidine bases. Carbamoyl-phosphate synthetase II, the rate-limiting enzyme of the de novo route, did not increase in the first 5 days after STZ treatment, the period of most rapid renal growth; a significant rise was seen at 14 days (+38%). Dihydroorotate dehydrogenase, a mitochondrial enzyme, showed the most marked rise (+147%) at 14 days. The conversion of orotate to UMP, catalyzed by the enzymes of complex II, was increased at 3 days (+42%), a rise sustained to 14 days. The salvage route enzyme, uracil phosphoribosyltransferase (UPRTase), showed a pattern of change similar to complex II. The effect of the decreased concentration of PPRibP on the activities of CPSII, for which it is an allosteric activator, and on activities of OPRTase and UPRTase, for which it is an essential substrate, is discussed with respect to the relative Ka and Km values for PPRibP and the possibility of metabolite channeling.

Animals↗
PubMed1991

Identification of Some Prostanoids in Aloe vera Extracts.

Screening of extracts from ALOE VERA revealed the presence of endogenous arachidonic acid, a potential precursor for the prostanoids synthesis. The presence of endogenous cyclooxygenase, in the plant extracts, was established by radiometric assay. Relatively high proportions of PGE (2) and TXB (2) and low proportions of other prostaglandins were identified in the plant extract when incubated with [ (14)C]-arachidonic acid. Other lipids present in this plant were examined and a high percentage of phosphatidylcholine and cholesterol was established. Possible importance of prostaglandins formed endogenously by the plant is discussed.

Journal Article↗
PubMed1991

ABO blood groups and the risk of diarrhea due to enterotoxigenic Escherichia coli.

To determine whether blood group O persons are at higher risk for enterotoxigenic Escherichia coli (ETEC) diarrhea, a case-control study was done for 17 months among rural Bangladeshis who were under systematic surveillance for diarrhea. Cases were children less than 3 years old who presented between 1 January 1985 and 1 June 1986 for care of heat labile (LT) or heat stabile toxin-producing ETEC diarrhea. Controls were of similar ages and were randomly selected from three community-based serosurveys between July 1985 and May 1986. No association between blood group O and ETEC diarrhea was found for the 510 cases and 641 controls, nor was an association evident for cases of each toxin phenotype. Further refinement of the case definition to include only patients with LT-ETEC diarrhea, without enteric copathogens, also failed to reveal a substantial association with blood group O. These data suggest that a strong association with ABO groups, analogous to that for cholera, does not exist for ETEC diarrhea.

ABO Blood-Group System↗
PubMed1991

Response of red cell and plasma volume to prolonged training in humans.

To clarify the role of progressive heavy training on vascular volumes and hematologic status, seven untrained males [maximal O2 uptake (VO2max) = 45.1 +/- 1.1 (SE) ml.kg-1.min-1] cycled 2 h/day at an estimated 62% of VO2max. Training was conducted five to six times per week for approximately 8 wk. During this time, VO2max increased (P less than 0.05) by 17.2%. Plasma volume (PV) measured by 125I increased (P less than 0.05) from 3,068 +/- 104 ml at 0 wk to 3,490 +/- 126 ml at 4 wk and then plateaued during the remaining four wk (3,362 +/- 113 ml). Red cell (RBC) mass (RCM) measured by 51Cr-labeled RBC did not change during the initial 4 wk of training (2,247 +/- 66 vs. 2,309 +/- 128 ml). As well, no apparent change occurred in RCM during the final 4 wk of training when RCM was estimated using PV and hematocrit (Hct). Collectively, PV plus RCM, expressed as total blood volume (TBV), increased (P less than 0.05) by 10% at 4 wk and then stabilized for the final 4 wk. During the initial phase of training, reductions (P less than 0.05) were also noted in Hct (4.6%), hemoglobin (Hb, 4.0%), and RBC count (6.3%). In contrast, an increase in mean cell volume (MCV, 1.7%) and mean cell Hb (2.3%) was observed (P less than 0.05). From 4 to 8 wk, no further changes (P greater than 0.05) in Hb, RBC, and MCV were found, whereas both mean cell Hb and Hct returned to pretraining levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗