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Biomedical subjects

A Omer

Publications and source records attributed to A Omer.

At least 19 recordsLinked to original sources
PubMed2006

Melaena as the presenting symptom of gastric mucosal injury due to blunt abdominal trauma.

Blunt abdominal trauma is a common cause of admission to the typical trauma centre. Hollow viscus injury from blunt trauma, however, is unusual and rarely involves the stomach. A 15 year old boy sustained a bicycle handle bar injury to the abdomen and presented to the casualty department four days later with melaena. A computed tomography (CT) scan of the abdomen showed normal findings but endoscopy revealed two "kissing" areas of mucosal ulceration on the anterior and posterior wall of the gastric antrum. The patient received a blood transfusion for anaemia but was otherwise treated conservatively and made a full recovery. The authors believe this to be the first reported case of melaena as the primary presenting symptom of gastric ulceration secondary to blunt abdominal trauma. Diagnosis of hollow viscus injuries due to blunt abdominal trauma requires a high index of suspicion and thorough investigation, particularly if the presentation is delayed.

Abdominal Injuries↗
PubMed2003

Field evaluation of latex agglutination test for detecting urinary antigens in visceral leishmaniasis in Sudan.

A latex agglutination test to detect urinary antigens for visceral leishmaniasis (VL) was studied. In 204 patients with suspected VL, KAtex had a sensitivity of 95.2% with good agreement with microscopy smears but poor agreement with 4 different serology tests. It was also positive in 2 confirmed VL cases co-infected with HIV. In all K4tex-positive confirmed cases actively followed up after treatment, the test became negative 1 month after completion of treatment. While IC4tex had a specificity of 100% in healthy endemic and non-endemic controls, the direct agglutination test (DAT) was positive in 14% of the KAtex-negative healthy endemic controls. KAtex is a simple addition to the diagnostics of VL particularly at field level and as a complementary test for the diagnosis of VL in smear-negative cases with positive DAT results.

Adolescent↗
PubMed2001

C-peptide responses after meal challenge in mice transplanted with microencapsulated rat islets.

AIMS/HYPOTHESIS: This study aimed to assess a response of microencapsulated rat islets to a meal challenge after being transplanted intraperitoneally into diabetic mice. METHODS: Microencapsulated rat islets or control naked syngeneic mouse islets were transplanted intraperitoneally into mice with streptozotocin-induced diabetes. Meal challenges were done 3, 6 and 9 weeks after transplantation. Glucose-induced insulin secretion from microencapsulated islets before and after transplantation was assessed in vitro. RESULTS: Within the first week, all animals transplanted with either microencapsulated rat islets or with syngeneic murine islets became normoglycaemic (< 11 mmol/l). At 4 and 6 weeks, body weight was less than normal in the non-diabetic control mice. Mice with the encapsulated rat islets had lower fasting glucose concentrations and more rapid glucose clearance after a meal challenge than the control mice. The group of mice with transplanted syngeneic islets had similar glucose profiles to control mice, except for slightly accelerated glucose clearance. The C peptide responses of mice with either microencapsulated or naked islets were clearly lower than the controls. An increase of C peptide appeared as early as 20 min in the plasma of the group with encapsulated islets, but this was considerably slower than in the other two groups. Microencapsulated rat islets retrieved 9 weeks after transplantation did not lose their ability to respond to glucose, but their output was less than half of the pretransplant control islets. CONCLUSION/INTERPRETATION: The delivery of C peptide and presumably the accompanying insulin are delayed by restrictions of the capsules and the peritoneal location. However, this delay in reaching peripheral target organs does not prevent microencapsulated grafts from efficiently clearing glucose after a meal.

Alginates↗
PubMed2001

A guided tour: small RNA function in Archaea.

In eukaryotes, the C/D box family of small nucleolar (sno)RNAs contain complementary guide regions that are used to direct 2'-O-ribose methylation to specific nucleotide positions within rRNA during the early stages of ribosome biogenesis. Direct cDNA cloning and computational genome searches have revealed homologues of C/D box snoRNAs (called sRNAs) in prokaryotic Archaea that grow at high temperature. The guide sequences within the sRNAs indicate that they are used to direct methylation to nucleotides in both rRNAs and tRNAs. The number of sRNA genes that are detectable within currently sequenced genomes correlates with the optimal growth temperature. We suggest that archaeal sRNAs may have two functions: to guide the deposition of methyl groups at the 2'-O position of ribose, which is an important determinant in RNA structural stability, and to serve as a molecular chaperones to help orchestrate the folding of rRNAs and tRNAs at high temperature.

Animals↗
PubMed2001

Complete protection of islets against allorejection and autoimmunity by a simple barium-alginate membrane.

We describe a new technique for microencapsulation with high-mannuronic acid (high-M) alginate crosslinked with BaCl(2) without a traditional permselective component, which allows the production of biocompatible capsules that allow prolonged survival of syngeneic and allogeneic transplanted islets in diabetic BALB/c and NOD mice for >350 days. The normalization of the glycemia in the transplanted mice was associated with normal glucose profiles in response to intravenous glucose tolerance tests. After explantation of the capsules, all mice became hyperglycemic, demonstrating the efficacy of the encapsulated islets. The retrieved capsules were free of cellular overgrowth and islets responded to glucose stimulation with a 5- to 10-fold increase of insulin secretion. Transfer of splenocytes isolated from transplanted NOD mice to NOD/SCID mice adoptively transferred diabetes, indicating that NOD recipients maintained islet-specific autoimmunity. In conclusion, we have developed a simple technique for microencapsulation that prolongs islet survival without immunosuppression, providing complete protection against allorejection and the recurrence of autoimmune diabetes.

Alginates↗
PubMed2000

Human peritoneal adhesions are highly cellular, innervated, and vascularized.

Peritoneal adhesions are a major complication of healing following surgery or infection and can lead to conditions such as intestinal obstruction, infertility, and chronic pain. Mature adhesions are the result of aberrant peritoneal healing and historically have been thought to consist of non-functional scar tissue. The aim of the present study was to analyse the cellular composition, vascularity, and extracellular matrix distribution of human peritoneal adhesions, to determine whether adhesions represent redundant scar tissue or are dynamic regenerating structures. Furthermore, the histological appearance of each adhesion was correlated with the clinical history of the patient, to determine whether maturity or intraperitoneal pathology influences adhesion structure. Human peritoneal adhesions were collected from 29 patients undergoing laparotomy for various conditions and were prepared for histology, immunocytochemistry, and transmission electron microscopy. All adhesions were highly vascularized, containing well-developed arterioles, venules, and capillaries. Nerve fibres, with both myelinated and non-myelinated axons, were present in adhesions from nearly two-thirds of the patients, with increased incidence in those with a malignancy. Approximately one-third of the adhesions contained conspicuous smooth muscle cell clusters lined by collagen fibres of heterogeneous size. Adipose tissue was a consistent feature of all the adhesions, with some areas displaying fibrosis. There appeared to be no correlation between the estimated maturity or site of each adhesion and its histological appearance. However, intraperitoneal pathology at the time of surgery did influence the incidence of some histological features, such as the presence of nerve fibres, clusters of smooth muscle cells, and inflammation. This study challenges previous concepts that adhesions represent non-functional scar tissue and clearly demonstrates that established adhesions are highly cellular, vascularized, and innervated, features more consistent with dynamic, regenerating structures.

Adult↗
PubMed1998

Rehabilitation of the expanded programme on immunization in Sudan following a poliomyelitis outbreak.

In 1993 a large outbreak of paralytic poliomyelitis occurred in Sudan as a result of an accumulation of large numbers of susceptible children that was accelerated by faltering immunization services. The extent of the outbreak led to the rapid rehabilitation of Sudan's Expanded Programme on Immunization (EPI); the government began financing vaccine purchase, operational aspects of EPI were decentralized, vaccine delivery was changed from a mobile to a fixed-site strategy, a solar cold chain network was installed, inservice training was resuscitated, and social mobilization was enhanced. National immunization days (NIDs) for poliomyelitis eradication were conducted throughout the country, including the southern states during a cease fire in areas of conflict. Measles immunization coverage was increased by offering measles vaccine during the second round of NIDs and subsequently through routine immunization services. Supplemental tetanus toxoid immunization of women of child-bearing age began in three provinces at high risk for neonatal tetanus. From 1994 to 1996 reported immunization coverage increased and the incidence of all EPI target diseases fell. Trends in coverage, disease incidence, financing, and the implementation of WHO-recommended disease-control strategies suggest that more sustainable immunization services have been re-established in Sudan.

Adult↗
PubMed1992

Surgical treatment of chronic fissure-in-ano: a prospective randomised study.

A prospective randomised study compared anal dilatation (n = 37), posterior internal sphincterotomy (n = 21) and lateral sphincterotomy (n = 20) in the surgical treatment of chronic anal fissures in 78 consecutive patients. All the operations were performed under general anaesthesia using standard techniques. Anal dilatation relieved anal pain early (immediate relief in 57% of patients; the mean pain-days +/- SD of 3.2 +/- 5.4 days). Anal fissures after this operation healed in a mean time +/- SD of 20.3 +/- 12.5 days, coming in second place to lateral sphincterotomy. Anal dilatation was followed by insignificant wound infection but its main disadvantage was a high rate of post operative anal incontinence (in 24.3% of patients). Fissurectomy and posterior internal sphincterotomy was followed by the longest period of post operative anal pain (mean +/- SD of 32.4 +/- 10 days) as compared to the other two operations. It was the least favourable operation. Lateral sphincterotomy was followed by early relief of pain (immediate relief in 95% of patients). It was not followed by wound infection. It had the quickest healing time for the fissures (a mean +/- SD of 14.7 +/- 8.7 days). It was followed by anal incontinence in only one patient. In conclusion lateral sphincterotomy was the most favourable operation and it is perhaps the operation of choice to perform in patients with chronic anal fissures needing surgical treatment.

Adult↗
PubMed1989

Muscle glutamine concentration and protein turnover in vivo in malnutrition and in endotoxemia.

A comparison of the changes in the concentration of glutamine [Gln] in skeletal muscle in a variety of catabolic states with the attendant changes in rates of protein synthesis and degradation indicates a number of substantial correlations which provide insight into both the way in which [Gln] is regulated in muscle and possible regulatory influences of [Gln] on protein balance. There is a striking direct correlation between [Gln] and the rate of protein synthesis in the whole data set. Further examination of this relationship in protein deficiency shows that the changes in [Gln] correlate mainly with the reductions in ribosomal concentration (RNA/protein) and with the decrease in the rate of protein degradation. Because the fall in [Gln] in protein deficiency is also correlated with the decrease in free T3 concentrations, it is suggested that in this case the correlations of [Gln] with rates of protein turnover may be incidental, reflecting thyroidal influences on both protein turnover and glutamine transport. In contrast, in endotoxemia the changes in [Gln] were highly correlated with the ribosomal activity, kRNA, and in this case [Gln] was inversely correlated with the rate of protein degradation. Similar correlated changes occur in starvation and in response to glucocorticoids, and it is suggested that the reductions in [Gln] in endotoxemia could be causally related to the development of insulin resistance and the inhibition of the translational phase of protein synthesis which occurs in these circumstances. The mechanism of the reduction in [Gln] and any linked inhibition of protein synthesis is unknown, but it is shown to be independent of prostaglandin production.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex Hormones↗
PubMed1987

Prevalence of thalassaemias in ethnic Saudi Arabians.

A study of the prevalence of alpha- and beta-thalassaemia and the sickle cell gene was carried out on 840 healthy adult male Saudi Arabians of different tribal origins. Complete blood count, haemoglobin electrophoresis and HbA2 estimation were carried out on all. Globin biosynthetic analysis was carried out on all 85 subjects with microcytic red cells and on 180 randomly selected subjects with normal red cell indices. The results showed prevalence of beta-thalassaemia of 3.0%, alpha/beta thalassaemia of 0.9%, alpha-thalassaemia of 43.3% and sickle trait of 5.7%. There were tribal variations in the prevalence of both alpha-thalassaemia and the sickle gene.

Adult↗
PubMed1986

Benzylpenicillin-induced neutropenia.

Neutropenia is a potentially serious complication of parenteral benzylpenicillin administration. It is thought to occur more frequently in patients receiving infusions of stored penicillin solutions. We report three cases of neutropenia produced after bolus injections of freshly prepared benzylpenicillin. Twenty-five other cases were reviewed from the literature and the data summarized.

Adolescent↗
PubMed1986

Association of red cell glucose-6-phosphate dehydrogenase with haemoglobinopathies.

A total of 1,112 randomly selected Saudi Arabs, of both sexes, living in Jeddah and the surrounding areas were screened for the phenotypic distribution of red cell glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD). They were also investigated for haemoglobin and for thalassaemia. Phenotyping of the haemoglobins and the red cell enzymes was carried out by starch gel electrophoresis and the dye-decolouration screening test, while the investigation for thalassaemia was carried out by globin-chain biosynthesis, followed by column chromatography. The red cell Gd- alleles were significantly associated with the sickle-cell gene in both the males (chi 2(1): AS-28.80; SS-4.89) and females (chi 2(1): AS-10.99; SS-13.16). A similar association was also observed between G6PD deficiency and thalassaemias in males (chi 2(1): alpha-thalassaemia - 3.13; beta-thalassaemia - 11.06) and females (chi 2(1): alpha-thalassaemia - 6.63). However, no such association was detected between red cell 6PGD types and haemoglobin genes. The results suggest that the red cell G6PD deficiency, sickle-cell and thalassaemia genes might have evolved as a result of the same ecological factor, probably malaria.

Adolescent↗
PubMed1985

Non-benign sickle cell anaemia in western Saudi Arabia.

Seventy-one Saudi and Yemeni Arabs with sickle cell anaemia from western Saudi Arabia aged between 1 1/2 and 42 years were studied. The mean steady state haemoglobin concentration of 8.1 g/dl was lower than that of 10.7 g/dl reported previously for sickle cell anaemia in eastern Saudi Arabia. The patients were divided into an SSLF group with fetal haemoglobin (HbF) of 10.0% or below (44 patients) and an SSHF group having HbF above 10.0% (27 patients). No significant differences were found in the haemoglobin concentrations, haematological indices and incidences of bone changes of the two groups. SSLF patients were significantly more prone to infections (P less than 0.01), however. Also, there was an overall high incidence of hepatomegaly (69.0%) and splenomegaly (54.9%) and hepatomegaly was significantly more common in the SSLF group (P less than 0.02). Many of the patients, even with HbF levels over 10.0%, did not follow a benign course and suffered from severe anaemia, infections of the respiratory and urinary tracts, bone pains and infarcts, or bossing of the skull. Rarer complications included hepatic crisis, chest syndrome, retinal haemorrhage, epistaxis and hemiplegia. It is therefore apparent that Saudi Arabian sickle cell anaemia, even in patients with raised haemoglobin F levels, may be as clinically severe as in African patients.

Adolescent↗