Biomedical subjects

M A Ali

Publications and source records attributed to M A Ali.

At least 91 records · Page 5Linked to original sources

PubMed1995

Antipyrine clearance and metabolite excretion in patients with chronic hepatitis C.

BACKGROUND/AIMS: Our aim was to study whether chronic hepatitis C affects the three metabolic pathways of the model drug antipyrine differently. METHODS: We measured antipyrine clearance from saliva as well as urinary excretion of its main metabolites 4-hydroxy-antipyrine, 3-hydroxy-methyl-antipyrine, and nor-antipyrine in 24 patients with chronic hepatitis C and in 21 healthy control subjects. Due to incomplete urine collection, 12 liver patients and three controls were excluded. RESULTS: Antipyrine clearance (mean +/- SD) was significantly lower in patients with chronic hepatitis C, 1.2 +/- 0.7 l.h-1 (n = 12), than in controls (n = 18), 2.2 +/- 1.0 l.h-1 (p = 0.006). The urinary excretion of each of the metabolites was depressed to an equal extent in liver patients. The severity of the liver disease, as assessed by Child Pugh score, serum albumin and bilirubin, correlated significantly with antipyrine clearance and urinary excretion of the metabolite 3-hydroxy-methyl-antipyrine. The hepatitis activity index (Knodell) correlated with 3-hydroxy-methyl-antipyrine and 4-hydroxy-antipyrine, only. CONCLUSIONS: Moderate-severe chronic hepatitis C does not seem to depress the three main metabolic pathways of antipyrine differently.

Adult↗

PubMed1995

Phosphorylase b kinase deficiency glycogenosis with cirrhosis of the liver.

We describe an Arab girl with complete absence of phosphorylase b kinase activity in the liver, symptomatic hypoglycemia, and persistently elevated serum aminotransferase values whose symptoms did not lessen with age; sequential liver biopsies showed progression to cirrhosis. Cirrhosis could not be ascribed to any other known cause. We conclude that type IX glycogenosis is not always associated with a benign outcome.

Child, Preschool↗

PubMed1995

Chromophobe cell carcinoma of the kidney. A clinicopathologic study of 21 cases.

The clinicopathologic features in a series of 21 chromophobe cell carcinomas are reviewed. Patients' ages ranged from 30 to 83 years (mean, 53 years), and the number of men and women was roughly equal. Major presenting complaints included hematuria, flank pain, and flank mass. All but two tumors were staged as tumor node metastasis (TNM) T2N0M0. Histologically, the carcinomas were composed of large cells with variably reticulated, translucent cytoplasm. The tumor cells could be divided into three types according to the extent and distribution of reticulated cytoplasm. Ultrastructurally, these reticulated areas were characterized by the presence of large numbers of microvesicles, which appeared to be unique to chromophobe cell carcinomas because ultrastructural examination of 20 clear cell carcinomas and six granular cell carcinomas failed to reveal similar structures. The origin of the vesicles appeared to be from saccular outpouchings from the outer mitochondrial membrane. Immunohistochemical studies revealed that all the tumors were variably positive for cytokeratins 8, 18, and 19, and epithelial membrane antigen but negative for vimentin. Flow cytometric DNA analysis of eight carcinomas revealed slightly hypodiploid cell populations in seven tumors. Of these, four also contained hyperdiploid cell populations. Follow-up (6-108 months) of 16 patients revealed all these patients to be alive and well. These findings further confirm the concept that chromophobe cell carcinoma is a special subtype of renal cell carcinoma in which the presence of microvesicles is a characteristic morphologic feature. Furthermore, loss of chromosomal DNA may also be a frequent, perhaps unique, feature of chromophobe cell carcinoma.

Adenocarcinoma↗

PubMed1995

A prospective study to determine the frequency and clinical significance of alloimmunization post-transfusion.

There is debate in the literature about the frequency and importance of delayed transfusion reactions. This uncertainty could reflect the endpoints used (clinical or serological) and the type of study (typically retrospective or case series). In this report we describe a prospective investigation to determine the frequency of alloimmunization post transfusion and whether the alloantibody production is a laboratory event or has clinical relevance. A total of 2490 patients were transfused 11,218 red cell concentrates. One or more blood samples were collected within 7 d post transfusion and screened for serological evidence of alloimmunization. If any antibody was detected the patient's post-transfusion sample was screened for biochemical evidence of haemolysis and the patient's chart reviewed for documentation of clinical signs of a transfusion reaction. Post transfusion alloimmunization occurred in 2.6% of the patients (95% CI 2.1-3.6%), who had no detectable alloantibody in pre-transfusion testing. For those 86 patients (3.5%) with alloantibodies detectable pretransfusion, 8.9% (95% CI 3.6-17.4%) developed additional aloantibodies. The most common alloantibodies detected were anti-Jka, anti-E and anti-K. Despite the high frequency of serological evidence of delayed transfusion reactions, only one patient (0.05%) had clinical evidence of a delayed haemolytic transfusion reaction (95% CI 0.0-0.27%). Serological evidence of a delayed transfusion reaction is common; however, these reactions rarely cause clinical symptoms.

Blood Group Incompatibility↗

PubMed1995

Regulation of melatonin secretion by light in the isolated pineal organ of the white sucker (Catostomus commersoni).

The effects of different lighting conditions and physical parameters of light were investigated in the isolated pineal organ of the white sucker kept under static or superfusion culture. The secretion of pineal melatonin is directly controlled by the photoperiod and completely suppressed under constant illumination. When pineal organs are exposed to unexpected light at night, the secretion of melatonin is significantly reduced within 15 min and reaches basal value after 30-35 min of light treatment. The inhibition of melatonin secretion by unexpected light at night depends on the irradiance, duration, timing of the treatment and the lighting history of the pineal organ.

Animals↗

PubMed1995

Diabetes mellitus in Egypt: risk factors and prevalence.

Major sociodemographic changes have occurred in Egypt to promote the development of noncommunicable diseases. We have performed a cross-sectional, population-based survey of persons > or = 20 years of age in Cairo and surrounding rural villages to describe the prevalence of diabetes risk factors, diagnosed diabetes, previously undiagnosed diabetes, and impaired glucose tolerance by age, sex, rural and urban residence, and socioeconomic status (SES). In the survey, we identified 6052 eligible households: 76% of household respondents completed a household examination and 72% of selected household respondents subsequently completed a medical examination. Exercise was assessed by questionnaire; adiposity by measurement of height, weight, and girths; and diabetes by history and 2-h 75 g oral glucose tolerance test. In rural areas, 52% of persons > or = 20 years of age were sedentary, 16% were obese, and 4.9% had diabetes. In lower SES urban areas, 73% were sedentary, 37% were obese, and 13.5% had diabetes. In higher SES urban areas, 89% were sedentary, 49% were obese, and 20% had diabetes. The combined prevalence of diagnosed and undiagnosed diabetes in the Egyptian population > or = 20 years of age was estimated to be 9.3%. Approximately half the diabetes was diagnosed and the other half was previously undiagnosed. The prevalence of diabetes in Egypt is high, and the gradient in risk factors and disease from rural to urban areas and in urban areas from lower to higher SES suggest that diabetes is a major, emerging clinical and public health problem in Egypt.

Adult↗

PubMed1995

Screening for diabetes mellitus in adults. The utility of random capillary blood glucose measurements.

OBJECTIVE: Because half of the people with non-insulin-dependent diabetes mellitus (NIDDM) are undiagnosed and because near-normal glycemic control can prevent diabetic complications, we evaluated the use of field-based random capillary blood glucose measurement as a screening test for NIDDM. RESEARCH DESIGN AND METHODS: A cross-sectional sample of 828 Egyptians > or = 20 years of age underwent both a random capillary blood glucose measurement performed with a portable reflectance meter in the field and an oral glucose tolerance test in the laboratory. The sensitivity and specificity of random capillary blood glucose measurements in predicting the presence of NIDDM were evaluated. RESULTS: Multivariate analyses showed that the screening test performed better when subjects had eaten shortly before the test (area under receiver operating characteristic curve, 0.87 for a 1-h postprandial period compared with 0.69 for an 8-h postprandial period) and that the optimal capillary blood glucose cutoff points to define a positive test increased with age. For a postprandial period of 1 h, cutoff points of 115 mg/dl for individuals 30 years of age and 140 mg/dl for those 75 years of age yielded similar performance characteristics (sensitivity 82% and specificity 78% for those 30 years old; sensitivity 81% and specificity 80% for those 75 years old). CONCLUSIONS: Adjusting random capillary blood glucose measurements for the postprandial period and using age-specific cutoff point values can improve performance of the screening test.

Adult↗

PubMed1995

Intraradicular disc herniation: a case report and review of the literature.

Intradural disc herniation accounts for < 0.3% of all disc herniations. Intraradicular disc herniation accounts for 4.1% of all such cases. Preoperative diagnosis is difficult, and a high index of suspicion during surgery is required for the diagnosis. We present a patient with intraradicular disc herniation in the lumbar region whose symptoms were severe enough to recommend surgery. The myelogram showed a block at the involved nerve root. Diagnosis of intraradicular herniation was made during surgery. The symptoms were immediately relieved by surgery. The literature on intradural and intraradicular disc herniation is reviewed.

Humans↗

PubMed1995

Effect of temperature on the lipid and fatty acid composition of Yersinia pseudotuberculosis.

In Yersinia pseudotuberculosis, the total lipid content is increased by decreasing the temperature of the growth medium. Thin layer chromatography of phospholipids revealed the presence of phosphatidy glycerols (PG) and phosphatidylethanolamine (PE) in the bacterium when grown at 26 degrees and 37 degrees C. Cardiolipin (CL) is present only in the bacterium grown at 37 degrees C, while lysophosphatidylglycerol (LPG) is present only in the bacterium grown at 26 degrees C. Unidentified phospholipids designated X1 was present in the bacterium at the two temperatures and X2 was only detected at 26 degrees C. Fatty acid unsaturation increased with decreasing temperature. Hexadecenoic acid (C16:1) content increased as the temperature was reduced to 26 degrees C. At lower temperature, stearic, oleic, linoleic, eicosanoic and linolenic acids were decreased. These observations support the view that regulation of membrane adaptation and the mechanism behind the responses might be more complex than is generally believed.

Adaptation, Biological↗

PubMed1995

Preoperative administration of antibodies against tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) and their impact on peritoneal adhesion formation.

This study investigates the effects of preoperative intravenous administration of antibodies against TNF-alpha and IL-1 on peritoneal adhesion formation. Fifty-six Sprague-Dawley rats (350-400 gm) were used in this study. Eight rats were used to empirically determine the amount of anti TNF-alpha and anti IL-1 needed for complete in vivo neutralization. This amount was used for preoperative treatment of selected groups. Forty-eight rats were divided into four equal groups (n = 12). All rats underwent a midline laparotomy. Ten cm square of cecal serosa was abraded, the peritoneal cavity was irrigated with normal saline, and the incision was closed in layers. Cultures were obtained intraoperatively and rats with positive cultures were excluded. Rats in Group 1 were not treated (control), while rats in Groups 2, 3, and 4 were treated with anti TNF-alpha, anti IL-1, and a combination of anti TNF-alpha and IL-1 respectively. All rats were killed at 3 weeks, and peritoneal adhesions were graded using a scale of 0 (none) to 3 (extensive, dense). Rats treated with anti IL-1 (Group 3) and those treated with a combination of anti TNF-alpha and anti IL-1 (Group 4) had significantly fewer adhesions when compared with Group 1 (control) (P < 0.01 and < 0.005, respectively). Least adhesion formation was associated with Group 4 rats. In conclusion, selective immunosuppression, at a molecular level, appears to have a significant impact on rates of postoperative peritoneal adhesion formation.

Animals↗

PubMed1995

The role of smooth-ended ameloblasts in enamel protein degradation in the rat incisor pigmentation.

Rats were perfused with glutaraldehyde. The lower incisors were dissected free. Mid-sagittal slice was cut through the entire incisor, demineralized. The pigmentation zone was isolated and further sliced into cross sections. These sections were incubated for CMPase. CMPase reaction product were associated with the lateral cell membrane of subclass II and Subclass III. This localization confirm the role of extracellular space of SAs as a route of enamel proteins during maturation.

Ameloblasts↗

PubMed1994

Small round cell tumor with divergent differentiation: cytologic, histologic, and ultrastructural findings.

A case study of desmoplastic small round cell tumor with divergent differentiation in a 13-yr-old boy is presented. Clinical, cytologic, histologic, immunohistochemical, and ultrastructural findings are reported. There was a close correlation between the various histologic and cytologic patterns. Immunohistochemical studies revealed strong positivity of many of the tumor cells for cytokeratin, vimentin, and desmin. Ultrastructurally, some of the tumor cells contained aggregates of cytoplasmic intermediate filaments. Fine-needle aspiration biopsy may suggest the diagnosis of desmoplastic small round cell tumor. Confirmation of the diagnosis may be provided by immunohistochemistry and electromicroscopy.

Abdominal Neoplasms↗

PubMed1994

Fine-needle aspiration biopsy diagnosis of extrarenal malignant rhabdoid tumor.

Two cases of extrarenal malignant rhabdoid tumors are presented in which diagnosis was suggested by fine-needle aspiration biopsy and confirmed by histologic and electron microscopic examination. Fine-needle aspiration smears in both cases revealed round to polygonal cells with vesicular nuclei and prominent nucleoli. Several tumor cells contained cytoplasmic inclusions composed of intermediate filaments. A majority of the tumor cells stained strongly for vimentin and cytokeratin. Electron microscopic examination revealed many cells with large aggregates of intermediate filaments corresponding to the cytoplasmic inclusions. Fine-needle aspiration biopsy may be used for diagnosing malignant rhabdoid tumor. The diagnosis may be further confirmed by immunohistochemistry and electron microscopy.

Abdominal Neoplasms↗

PubMed1994

Melatonin activity rhythms in eyes and cerebral ganglia of Aplysia californica.

In this study, we used a sensitive and specific radioimmunoassay to detect a substance which appears to be melatonin, an acetylation and methylation product of serotonin, in the eyes and central nervous system of the opisthobranch mollusc Aplysia californica. This identification was confirmed in the eyes by HPLC with fluorimetric detection. Melatonin activity was high in the eyes during the day and in the cerebral ganglia during the night. Only small amounts of melatonin were present at midday or midnight in the pedal ganglia. A single 1-hr exposure to light in the middle of the dark phase resulted in a sharp increase of melatonin in the eyes, whereas no such activity was detectable in cerebral and pedal ganglia. Eyes maintained in culture exhibited a diurnal rhythm of released melatonin activity over a 3-day period. These results suggest that melatonin is produced in A. californica in a rhythmic pattern different from that associated with pineal melatonin production in vertebrates.

Animals↗

PubMed1994

Effect of gibberellic acid on broiler chickens performance and some metabolic parameters.

Feeding 2-weeks old broiler chicks on gibberellic acid (GA3)-containing diets (0, 1, 5, 25 and 125 ppm) for 3-weeks led, generally, to nonsignificant increase of body weight, decreased feed consumption and better feed conversion (on 25-125 ppm). Yet, the percentages of the carcass and the other organs (liver, gizzard, heart) and glands (adrenal, thyroid and pituitary) weights were lower comparing with the control (0 level). Blood protein and magnesium concentrations raised significantly. Blood glucose increased but not significantly. There was remarkable decrease (P < or = 0.01) in transaminases activity. The muscular protein decreased, whereas the fat percentage significantly increased. The bone reflected lower density and mineral (calcium, magnesium and phosphorus) contents. GA3 led to numerous histological lesions in different organs. Two-weeks withdrawal period did not ameliorate the negative effects of GA3-inclusion whether on the dressing percentages, blood picture, or on the muscles and bone constituents.

Animal Feed↗

PubMed1994

Myelodysplastic syndrome with prolonged reticulocyte survival mimicking hemolytic disease.

A patient with myelodysplastic syndrome (refractory anemia) with marked and persistent reticulocytosis is presented. A referring diagnosis of hemolytic disease had been made. However, the 51Cr red cell survival was normal (T1/2 24 days). Reticulocyte morphology, red cell creatine content, and in vitro reticulocyte survival studies have suggested that the reticulocytosis arose as a consequence of delayed maturation of the reticulocytes. Two patients with myelodysplastic syndrome and delayed reticulocyte maturation have previously been described; in both patients, however, red cell survival was also shortened. Anemia with reticulocytosis, mimicking hemolytic disease, may be an unusual presentation of myelodysplastic syndrome.

Aged↗

PubMed1994

Multiple circadian oscillators in the photosensitive pike pineal gland: a study using organ and cell culture.

The fish pineal organ contains typical and, in some species, modified photoreceptor cells involved in the photoperiodic control of melatonin production. In the majority of species studied, the rhythm in melatonin production is driven by an intra-pineal circadian oscillator synchronized by the light:dark cycle. In the present study, it is shown that the endogenous rhythm in melatonin release of superfused pike pineals maintained under constant darkness is expressed at temperatures of 19 degrees C, 20 degrees C, 25 degrees C, and 30 degrees C (period > 24 hr), but not at temperatures of 10 degrees C and 15 degrees C. Under constant darkness, pineal fractions containing either typical photoreceptors, modified photoreceptors, or both behaved like total organs. Dissociated pike pineal cells, cultured statically at 20 degrees C, expressed a high amplitude rhythm in melatonin secretion under a light:dark cycle. Under constant darkness, circadian oscillations, which appeared better sustained than in organ culture, were also observed. This study provides the first evidence that the rhythmic production of melatonin, by a fish pineal, is driven by a population of circadian oscillators or clocks. It is hypothesized that each typical and modified photoreceptor might be the locus of a circadian clock. Damping of the overall rhythm under constant darkness might reflect the desynchronization (uncoupling) between these clocks and/or damping of individual oscillators.

Animals↗

PubMed1994

Rhythmic secretion of melatonin by the superfused pike pineal organ: thermo- and photoperiod interaction.

In the pineal organ of the pike (Esox lucius, teleost), the rhythmic production of melatonin by the photoreceptor cells is governed by a population of endogenous circadian oscillators, synchronized and entrained by the light/dark (L/D) cycle. Production of melatonin is inhibited by light and highly increased in the dark. In the present study, isolated and superfused pike pineals were exposed to a 24-hour temperature cycle of high (10 degrees C) or low (4 degrees C) amplitude, either under L/D, or under constant darkness. Under L/D, photoperiod is the dominant entraining stimulus for the melatonin secretion rhythm. It was high during the dark phase and low during the light phase, either under cold light/warm dark or under warm light/cold dark conditions. Under a warm light/cold dark cycle, the amplitude of the melatonin rhythm was reduced. In pineals cultured at 10 degrees C, a 20 degrees C temperature pulse potentiated or reduced the night-induced rise in melatonin production when applied, during the dark or during the preceding light phase, respectively. Under constant darkness, high- or low-amplitude temperature cycles could synchronize the rhythmic production of melatonin, which peaked with the high temperature. However, the shape of the oscillation could appear modified under warm subjective-L/cold subjective-D, depending on the experimental conditions. Finally, the rhythmic release of melatonin synchronized by a temperature cycle under constant darkness was no longer observed after removal of the external zeitgeber. The present study provides direct evidence that the pineal acts as a photothermotransducer.

Animals↗