Biomedical subjects

M A Ali

Publications and source records attributed to M A Ali.

At least 145 records · Page 8Linked to original sources

PubMed1991

Long-term efficacy of repeat argon laser trabeculoplasty.

The role of repeat argon laser trabeculoplasty (RALT) in the management of open-angle glaucoma is controversial. To determine the long-term efficacy of RALT, the authors reviewed case records of 44 patients (50 eyes) who received RALT for uncontrolled glaucoma at the Wills Eye Hospital before 1986. Success was defined as a 3 mmHg or greater decrease in intraocular pressure (IOP) to less than 22 mmHg, and no further surgical intervention. By life table analysis, RALT was successful in 35% of eyes at 6 months, in 21% at 12 months, in 11% at 24 months, and in 5% at 48 months. Thirty-three percent of eyes in which primary ALT was successful for 1 year were successful 12 months after RALT. Complications included IOP spikes in 12%. In conclusion, RALT was generally not effective for long-term control of open-angle glaucoma, but may be useful as a temporizing measure. However, this use of RALT must be weighed against the risks of complications and the additional progression of disease before more definitive surgical intervention.

Adult↗

PubMed1991

Intestinal lymphangiectasia masquerading as coeliac disease.

Intestinal lymphangiectasia (IL) usually presents with either non-specific general or gastro-intestinal symptoms. As IL may mimic other gastro-intestinal disorders, the diagnosis is often delayed. Intestinal lymphangiectasia was diagnosed in three children who were originally treated as cases of coeliac disease. Two were sisters who had been placed on a gluten-free diet, for 3 years in one and 10 years in the other, with no favourable response. The third patient had been tried on various formulae and underwent many investigations for failure to thrive, oedema, abdominal distension and recurrent chest infections. The diagnosis of IL was based on clinical history, physical examination and radiological and histological findings. The three patients were commenced on a medium-chain triglyceride-based diet and vitamins, with satisfactory results.

Adolescent↗

PubMed1991

Human learning during general anaesthesia and surgery.

To determine if learning occurs during general anaesthesia, 72 women undergoing surgery were given postoperative implicit memory tests in which performance could be influenced by auditory information presented during general anaesthesia. Two methods of anaesthesia were used: nitrous oxide and opioids (n = 24) or nitrous oxide and isoflurane (1, 1.3 and 1.5 MAC for n = 12, 24 and 12, respectively). Three tests showed some retention, apparently unconscious, of information presented during anaesthesia: in Behavioural Suggestions tests, patients who were instructed during anaesthesia to touch a particular body part (ear or nose) during later questioning touched the "correct" (suggested) body part longer than the "incorrect" (not suggested) body part during a postoperative interview on the day of surgery (means 2.5 vs 0.2 s); in World Completion tests, patients shown a page containing the first three letters of words and asked to give words beginning with those letters gave more words from a list that had been played during anaesthesia than from a list not played (means 0.48 vs 0.27 words); in Nonsense Word tests, patients who were played different nonsense words between two and 16 times during anaesthesia preferred and guessed more accurately those that had been played most often (16 times) relative to those played less often in subsequent preference and recognition tests (means 56% vs 46% for preference and 62% vs 48% for recognition), while showing no such patterns in additional control tests. Learning did not vary with the method of anaesthesia, as might have been expected if learning was a monotonic function of brain depression. Some information processing functions of the brain evidently continue to function during adequate general anaesthesia.

Adult↗

PubMed1991

Congenital hepatic fibrosis in Saudi Arabia.

Congenital hepatic fibrosis (CHF) is a recognized cause of portal hypertension with oesophageal varices, gastro-intestinal haemorrhage and cholangitis in children without significant impairment of hepatic or renal function. This report describes the varied clinical presentation of CHF as seen at King Faisal Specialist Hospital and Research Centre (KFSH & RC) and emphasizes the clinical patterns that should enable a pediatrician to consider the diagnosis. Fourteen children with CHF were diagnosed between 1981 and 1988. The age at presentation ranged from 1.8-14 years (mean: 7.5 years); clinical manifestations at diagnosis were splenomegaly (12), hepatomegaly (11), failure to thrive (10), marked abdominal distention (4), and fever (4). Liver function tests were normal except for high alkaline phosphatase. Eight patients had polycystic kidneys confirmed on ultrasound examination. Upper gastro-intestinal endoscopy showed oesophageal varices of variable severity in all eight patients examined. Splenoportography revealed splenic vein occlusion in one patient. One patient died within days of admission with convulsions, coma, and aspiration pneumonia. One patient was lost to follow-up. The remaining 12 patients are all alive and receive regular follow-up. Two patients required splenorenal shunt. In view of the prevalence of consanguinity in Saudi Arabia, the diagnosis of CHF should be considered in children with hepatomegaly despite normal liver function tests, and particularly in those with renal abnormalities and/or evidence of portal hypertension.

Adolescent↗

PubMed1991

Efficacy of therapeutic suggestions for improved postoperative recovery presented during general anesthesia.

There have been claims that the postoperative course of patients may be improved by presentation during general anesthesia of therapeutic suggestions which predict a rapid and comfortable postoperative recovery. This study evaluated the effectiveness of such therapeutic suggestions under double-blind and randomized conditions. A tape recording predicting a smooth recovery during a short postoperative stay without pain, nausea, or vomiting was played during anesthesia to about half the patients (N = 109), while the remaining, control patients were played a blank tape instead (N = 100). The patients were primarily undergoing operations on the fallopian tubes, total abdominal hysterectomy, vertical banding gastroplasty, cholecystectomy, and ovarian cystectomy or myomectomy. The anesthesia methods consisted of either isoflurane with 70% nitrous oxide in oxygen to produce end-tidal concentrations of 1.0, 1.3, or 1.5 MAC; or 70% nitrous oxide in oxygen combined with high or low doses of opioids. Assessments of the efficacy of the therapeutic suggestions in the recovery room and throughout the postoperative hospital stay included: the frequency of administration of analgesic and antiemetic drugs; opioid doses; the incidence of fever; nausea, retching, and vomiting; other gastrointestinal and urinary symptoms; ratings of pain; ratings of anxiety; global ratings of the patients' physical and psychological recoveries by the patients and their nurses; and length of postoperative hospital stay. There were no meaningful, significant differences in postoperative recovery of patients receiving therapeutic suggestions and controls. These negative results were not likely to be due to insensitivity of the assessments of recovery, as they showed meaningful interrelations among themselves and numerous differences in recovery following different types of surgery. Widespread utilization of therapeutic suggestions as a routine operating room procedure seems premature in the absence of adequate replication of previously published positive studies.

Adult↗

PubMed1991

Overestimation of fetomaternal haemorrhage by the acid-elution technique in mothers with beta-thalassaemia minor.

In Rh-negative women, it is important to quantify the magnitude of an Rh-positive fetomaternal haemorrhage (FMH) so that sufficient Rh immune globulin (RhIg) can be administered early in the post-partum period to prevent alloimmunization. The standard post-partum dose of RhIg varies from 100 micrograms in the UK to 300 micrograms in North America. It is therefore important to identify all Rh-negative women who have had an FMH greater than 10 ml in the UK or greater than 30 ml in North America because an FMH greater than these amounts will affect the dose of RhIg that is administered. As acid-elution techniques can overestimate the magnitude of an FMH in the presence of an elevated maternal haemoglobin F level, we performed a prospective study to determine how often this occurred. Of 1,894 consecutive Rh-negative mothers who delivered Rh-positive infants, whose blood was screened for an FMH greater than 10 ml of fetal blood using an acid-elution procedure, 11 were found to have an FMH over 10 ml. In five of these 11 women, the volume of FMH was less than 10 ml using an alternative technique (rosette test) to assess the FMH size. Six of these women were found to have beta-thalassaemia minor on the basis of a low MCV, and high haemoglobin A2 and/or high haemoglobin F levels. In five of these the FMH was significantly overestimated by the acid-elution technique compared to the rosette technique. Therefore, in the presence of a maternal condition, which may result in an elevated haemoglobin F level, an FMH estimated to be over 10 ml in the UK or 30 ml in North America using an acid-elution procedure, should be confirmed by an alternative technique, which does not involve the estimation, directly or indirectly, of haemoglobin F.

Cell Count↗

PubMed1991

Ultrastructure and opsin immunocytochemistry of the pineal complex of the larval Arctic charr Salvelinus alpinus: a comparison with the retina.

The fine structure and opsin immunocytochemistry of the pineal and parapineal organs of the salmonid fish Salvelinus alpinus, the landlocked Arctic charr, were studied and compared with the retina in various developmental stages, from prehatching to two-month-old. For opsin immunocytochemistry two polyclonal antibovine rhodopsin and the monoclonal antichicken opsin antibodies OS-2 (detecting blue and green pigments) and OS-1 (detecting green and red pigments) were used. Histologically, the pineal organ consists of nervous tissue like that of the retina. It is composed of photoreceptor pinealocytes, which formed axon terminals containing synaptic ribbons, on the dendrites and perikarya of secondary pineal neurons. Already in prehatching embryos, both the pineal and retinal photoreceptors display well-developed outer segments and form synaptic terminals. The distal part of the pineal organ differentiates earlier than its proximal stalk. The differentiation of the retina starts centrally, but the caudal and dorsal retinae are differentiated earlier than the rostral and ventral ones. At the end of the larval period, the lateral retina is still undifferentiated. In all stages studied, (rhod)opsin immunoreactivity was found in the outer segments of the pineal organ and rod-type retinal photoreceptors, a finding speaking in favour of the presence of the opsin of a rhodopsin/porphyropsin. Cone-type retinal photoreceptors identified morphologically in the pre- and posthatching stages were opsin-immunonegative with the four primary antisera used. This result suggests that in the charr the opsins of cone visual pigments differ in their chemical nature from those of rhodopsin/porphyropsin. The parapineal organ was opsin immunonegative. Using the monoclonal antibody OS-2 opsin immunoreactivity was also detected in inner segments, perikarya, and pedicles of rod-type photoreceptors of both retina and pineal organ of embryos and 1- to 4-day-old larvae. This may indicate a high level of opsin gene expression during photoreceptor growth around hatching. The well-developed pineal organ and its opsin content are discussed in connection with the photonegative behaviour of the larval charr.

Animals↗

PubMed1991

Oral iron absorption in hemodialysis patients treated with erythropoietin.

The effect of the erythropoietic activity of the bone marrow on oral iron absorption was investigated in hemodialysis patients. The subjects were enrolled in the Canadian Multicentre Erythropoietin (EPO) Trial; four patients were in the placebo group and four were in the EPO group. All patients were maintained iron replete with oral and intravenous iron as required to maintain ferritin greater than 200 micrograms/L. All patients had two oral radio-labelled iron (59Fe) absorption tests. The first took place during the last two months of the EPO trial, and the second within the first three months of the maintenance phase where all patients received EPO. The erythropoietic activity of the bone marrow was changed by administration of EPO to the placebo group. The group with an unchanged EPO prescription served as controls. The placebo group absorbed 4.5% and 3.9% of 59Fe pre- and post-EPO, respectively (delta NS). The control group absorbed 3.2% and 4.4% of 59Fe and thus similarly showed no change in iron absorption. Oral iron absorption is low in hemodialysis patients, and is not augmented by short-term EPO therapy. The high level of iron stores (i.e., ferritin) present in the Canadian EPO study patients may prevent an effect of the erythropoietic stimulation on iron absorption. Although an increase in iron absorption by EPO was not demonstrated, a type II error could not be excluded.

Adult↗

PubMed1991

Causes of lymphadenopathy in Egyptian children other than malignancy.

Fifty children aged 3 to 12 years presented with cervical or inguinal lymph nodes enlargement were selected from Zagazig University Hospitals. They were subjected to routine laboratory examination as well as histopathological & immunopathological studies. The results revealed eosinophilia and intestinal parasites in 80 percent. Besides, pediculosis and flea dermatitis were also demonstrated in 30 and 12 percent respectively. Histopathological studies of the nodal tissues revealed sinus hyperplasia (ten cases), reactive paracortical hyperplasia (30 cases) and necrosis and caseition (ten cases). Infiltration with eosinophils was demonstrated in the nodal tissues of 40 cases. Immunopathologyical studies revealed cytotoxic T-cells in all the cases, and helper T lymphocytes in only 15 cases. It is concluded that this may give an explanation of some causes of lymphadenopathy in Egyptian children other than malignancy.

Biopsy↗

PubMed1991

Budd-Chiari syndrome in association with Behçet's disease.

Budd-Chiari syndrome developed in 3 patients with preexisting Behçet's disease. Benign intracranial hypertension was the chief presenting complaint in one patient, who later suffered extensive inferior vena caval and hepatic vein thrombosis, with manifestations of Budd-Chiari syndrome. She did not respond to treatment and subsequently died of hepatic coma. In the other 2 patients, Budd-Chiari syndrome was confirmed by liver biopsy. Both patients made a good recovery and remain well at the time of this report.

Adult↗

PubMed1990

Recurrent acute splenic sequestration crisis due to interacting genetic defects: hemoglobin SC disease and hereditary spherocytosis.

A 14-year-old boy with hemoglobin SC disease and alpha-thalassemia-2 experienced five episodes of acute splenic sequestration crisis (ASSC), while two of his siblings with identical globin genotypes (SC and -alpha/alpha alpha) had no such experience. To determine if an additional red blood cell (RBC) defect was responsible for the unusual occurrence of frequent ASSCs, we performed detailed rheologic characterization and membrane protein analysis on RBCs from the proband and other members of his family. Reduced surface area, increased mechanical instability, and decreased spectrin content of the membrane, distinguishing features of RBCs in hereditary spherocytosis, were observed in cells from the proband and his mother, but not in cells from other family members. These findings are consistent with the dominant inheritance of spherocytosis by the proband. We suggest that the combined effects of SC disease and spherocytosis in the proband resulted in decreased RBC deformability and led to increased splenic trapping, intrasplenic sickling, and consequently, recurrent sequestration crisis. Marked clinical and hematologic improvement occurred from splenectomy. Thus, inheritance of interacting genetic defects, sickling hemoglobinopathy, and hereditary spherocytosis appear to be responsible for the unusual clinical manifestation of recurrent ASSC in this patient.

Anemia, Sickle Cell↗

PubMed1990

Fine-needle aspiration biopsy of seminoma and dysgerminoma: cytologic, histologic, and electron microscopic correlations.

Cytomorphologic features in a series of fine-needle aspiration biopsies from eight patients with seminoma or dysgerminoma were reviewed, and the findings were further correlated with histopathologic and ultrastructural appearances. Three cell types were encountered. Type I was least differentiated and least frequent. Type II was most frequent and had well-developed cytoplasm rich in organelles. Type III was similar to type II but also contained abundant cytoplasmic glycogen. In cytology smears, type III cells contained large punched-out cytoplasmic vacuoles corresponding to the areas of glycogen deposition. The background contained a variable mixture of inflammatory cells including lymphocytes, plasma cells, epithelioid cells, and epithelioid granulomas. The significance of these findings in the diagnosis of seminoma or dysgerminoma and the distinction from other germ-cell and non-germ-cell tumors is briefly discussed.

Adolescent↗

PubMed1990

Fine-needle aspiration biopsy of mucus-producing medullary carcinoma of thyroid: report of a case with cytologic, histologic, and ultrastructural correlations.

Cytologic features of aspiration smears from a mucus-producing medullary carcinoma of the thyroid are described. Two patterns of mucin production by the tumor cells were noted. In some cells, mucin was present as numerous small cytoplasmic vacuoles with ultrastructural morphology characteristic of mucin granules. Other cells had larger, more well-defined cytoplasmic mucin vacuoles; on ultrastructural examination, they were found to be intracytoplasmic lumina. Although mucin production has been demonstrated in several histologic studies of medullary carcinoma, it has not been previously recognized in fine-needle aspiration biopsies from this neoplasm.

Biopsy, Needle↗

PubMed1990

Fine-needle aspiration biopsy diagnosis of endodermal sinus tumor: histologic and ultrastructural correlations.

Fine-needle aspiration biopsies from five patients with endodermal sinus tumors (ESTs) were reviewed, and the findings were correlated with histologic and ultrastructural appearances. In the aspiration smears, two types of tumor cells were seen, forming clusters of variable sizes. Type A cells had distinct cell borders, and their cytoplasm contained only occasional vacuoles. Type B cells had ill-defined cell borders and formed syncytial clusters; their cytoplasm was characterized by large numbers of rounded vacuoles. The background contained patches of mucoid material and macrophages with foamy cytoplasm. Eosinophilic hyaline cytoplasmic bodies and irregular deposits of intercellular basement membrane-like material were recognized easily in aspiration smears. These features correlated well with histologic and ultrastructural appearances. The significance of these findings in the fine-needle aspiration biopsy diagnosis of EST and its distinction from other germ-cell and non-germ-cell tumors is discussed.

Adult↗

PubMed1990

Serologic specificity of antibodies to herpes simplex virus glycoprotein B present in human sera. Analysis by transient expression of glycoprotein B-derivatives.

Glycoprotein B (gB) is an essential glycoprotein of herpes simplex virus (HSV) and a major target for cellular and humoral immune response in the infected host. In the present study, we have analyzed the pattern of reactivity of a panel of 23 HSV-seropositive patient sera using as test antigens gB derivatives made in COS cells in a transient expression assay. Our results show that nearly all the sera tested, reacted with wild-type gB or tgB (772) (that lacks 102 amino acids cytoplasmic domain). However, when tgB (477 amino acids) or gBdl (an inframe deletion between amino acids 477-772) were used as test antigens only 12 out of 23 sera tested positive. Further analysis using competition assays revealed that these sera can be classified into at least two groups: (i) that contain gB-reactive antibodies reactive to intact gB or tgB (772); (ii) that contain antibodies that recognize all forms of gB-derivatives tested. The results presented here underscore the potential limitations in using certain truncated forms of gB as antigens for subunit vaccine or in the serodiagnosis of HSV infection.

Antibodies, Viral↗

PubMed1990

Oligomerization of herpes simplex virus glycoprotein B occurs in the endoplasmic reticulum and a 102 amino acid cytosolic domain is dispensable for dimer assembly.

Glycoprotein B (gB) is an essential protein specified by herpes simplex virus and a major envelope component of the virions. It is known to assemble into noncovalently associated dimers. The aim of this study was to investigate the role of topogenic domains of gB in dimer assembly and the intracellular location at which gB dimers are assembled. Therefore, dimer analyses were performed on intact gB and its three COOH-terminus-truncated gB derivatives encoding NH2-terminal 772, 586, and 477 amino acids (aa) of the mature gB, using SDS-polyacrylamide gel electrophoresis and sucrose gradient assays. Dimers were detected in gB and in tgB(772 aa), but were absent from tgB(586 aa) and from tgB(477 aa). These results showed that a 102 aa cytosolic domain (aa 773-874) is not required for the assembly of gB dimers. In addition, using endoglycosidase H treatment and dimer analysis of gB synthesized during 7 min pulse-labeling period, we have demonstrated that ER is the subcellular organelle at which gB monomers are assembled into dimeric forms.

Amino Acids↗

PubMed1990

Bioavailability of iron in hemodialysis patients treated with erythropoietin: evidence for the inhibitory role of aluminum.

The dose of recombinant human erythropoietin (r-HuEPO) required to correct the anemia of end-stage renal disease (ESRD) varies among patients. The response to r-HuEPO is impaired if absolute or relative iron deficiency exists. Aluminum may cause a microcytic anemia in patients with ESRD, but the mechanism remains incompletely defined. Twenty-two patients in the Canadian Multicentre EPO trial were studied for 6 months. In this randomized double-blind placebo-controlled trial, free erythrocyte protoporphyrin (FEP) was used as an indicator of iron-deficient deficient erythropoiesis. The relationship of FEP to the estimates of iron availability (serum iron, transferrin saturation, ferritin) and iron utilization (corrected reticulocyte count, hemoglobin) was evaluated by multiple linear regression analysis. The effect of aluminum on FEP was evaluated by adjusting the statistical model for this variable. All patients were iron replete as assessed by serum ferritin. FEP was not related to serum aluminum before administration of r-HuEPO, but it was significantly correlated with aluminum in the treated group. In hemodialysis patients treated with r-HuEPO, the proportion of the variability explained by the parameters of iron utilization and iron availability was 0.27. The effect of aluminum increased this to 0.59. In hemodialysis patients not receiving r-HuEPO, the proportion of variability in FEP explained by the model increased from 0.16 to 0.28 by adjusting for aluminum. The data support the hypothesis that aluminum interferes with the bioavailability of stored iron for erythropoiesis and thus may result in a microcytic anemia in patients with ESRD or may blunt their response to r-HuEPO therapy.

Adult↗

PubMed1990

Appraisal of the quality of assessment of memory in anesthesia and psychopharmacology literature.

To test the hypothesis that there are important differences between studies on memory published in anesthesia literature and those published in the psychopharmacology literature, we compared the two from the period January 1978 through May 1988 to identify deficiencies in the design and methodologies used and to provide guidelines for future experiments. Eight-eight articles in each discipline were reviewed. The sample sizes were larger in the articles in anesthesia journals than in those in psychopharmacology journals (medians 52.5 vs. 18 subjects, respectively). Most (85%) of the studies in the anesthesia literature used patients, who had a median age of 38.9 yr and included a median of 28 women among the subjects per study. In contrast, the majority (60%) of the studies in the psychopharmacology literature used healthy volunteers, who had a median age of 23.6 yr and included a median of only 3.5 females among the subjects per study. Characteristics more common in the psychopharmacology than in the anesthesia literature, respectively, were use of a control or placebo group (90% vs. 42%), double-blind design (80% vs. 47%), use of pre- and posttreatment memory measurements (64% vs. 23%), use of multiple memory tests with distinct equated stimuli (83% vs. 8%), relation of methodology to some theoretical model of memory (72% vs. 17%), and use of other behavioral tests (68% vs. 48%). Relative to the psychopharmacology literature, the anesthesia literature used pictures as stimuli for the memory tests more often (44% vs. 14%, respectively) and words less often (11% vs. 67%) and relied heavily on questions about recall of perioperative events (41% vs. 0%). There is room for improvement in both types of literature, and more so in the anesthesia literature.

Anesthesia↗