Munc18c function is required for insulin-stimulated plasma membrane fusion of GLUT4 and insulin-responsive amino peptidase storage vesicles

To examine the functional role of the interaction between Munc18c and syntaxin 4 in the regulation of GLUT4 translocation in 3T3L1 adipocytes, we assessed the effects of introducing three different peptide fragments (20 to 24 amino acids) of Munc18c from evolutionarily conserved regions of the Sec1 protein family predicted to be solvent exposed. One peptide, termed 18c/pep3, inhibited the binding of full-length Munc18c to syntaxin 4, whereas expression of the other two peptides had no effect. In parallel, microinjection of 18c/pep3 but not a control peptide inhibited the insulin-stimulated translocation of endogenous GLUT4 and insulin-responsive amino peptidase (IRAP) to the plasma membrane. In addition, expression of 18c/pep3 prevented the insulin-stimulated fusion of endogenous and enhanced green fluorescent protein epitope-tagged GLUT4- and IRAP-containing vesicles into the plasma membrane, as assessed by intact cell immunofluorescence. However, unlike the pattern of inhibition seen with full-length Munc18c expression, cells expressing 18c/pep3 displayed discrete clusters of GLUT4 abd IRAP storage vesicles at the cell surface which were not contiguous with the plasma membrane. Together, these data suggest that the interaction between Munc18c and syntaxin 4 is required for the integration of GLUT4 and IRAP storage vesicles into the plasma membrane but is not necessary for the insulin-stimulated trafficking to and association with the cell surface.

Biochemical profiles of hydatid cyst fluids of Echinococcus granulosus of human and animal origin in Libya

A comparative study on the biochemical parameters in hydatid cyst fluids of sheep, goats, camels, cattle and human cystic forms of Echinococcus granulosus has been made in Libya. Quantitative variations in the levels of sodium, potassium, calcium, cholesterol, glucose, urea, creatinine and gamma glutamyl transpeptidase (gamma GT) were found in the cystic fluids of different host origins although these differences were statistically insignificant compared with the hydatid fluids of sheep. However, the concentration of triglycerides and proteins were significantly elevated in the cyst fluids of sheep compared with the other fluids studied. Similarities in the biochemical composition of different hydatid cyst fluids suggest the existence of sheep strains of E. granulosus in human and other domestic animal intermediate hosts in Libya.

Angiolymphoid hyperplasia with eosinophilia (alhe) versus kimura's disease : Changing concepts

The clinico-pathological differences between Kimura's angiolymphoid hyperplasia with eosinophilia are presented to emphasize that they are two separate disease entities which until now were considered as the same disease.

Pneumothorax due to electrical burn

A 25-year-old male developed early as well as delayed (15 days post burn) pneumothorax of right side following high voltage, 1100 KV, electrical burn of the right side of the chest wall. Diagnosis was established by clinical examination and chest x-ray. Intercostal tube drainage with underwater seal relieved the patient of pneumothorax.

Prevalence of Helicobacter pylori antibodies in endoscopy personnel and non-medical volunteers of Karachi

Prevalence of Helicobacter pylori (Hp) is high in developing countries. As endoscopy personnel are at greater risk of exposure to gastric secretions, they are apparently at higher risk of acquiring this infection. The aim of this study was to determine prevalence of Hp antibodies in endoscopy staff and compare it with non-medical volunteers and assess any additional risk of occupational exposure to Hp in the former group. Thirty-three subjects working in endoscopy suites of different hospitals of Karachi and 33 non-medical volunteers were investigated for the prevalence of Hp antibodies by using a commercially available rapid qualitative test (FlexPack HP; Abbott). The two groups were comparable in mean age, sex and social class. Twenty-six of 33 (79%) of the endoscopy personnel and 19/33 (58%) of the non-medical volunteers were positive for Hp serology (p = 0.06 R.R 1.37). Among the endoscopy personnel 13/14 (93%) of endoscopy assistants were positive and this subgroup had a significantly higher prevalence of Hp antibodies as compared to the control group (p = 0.019). No correlation could be found between the positive serology and symptoms of dyspepsia.

Hepatitis A and cytomegalovirus infection precipitating acute hemolysis in glucose-6-phosphate dehydrogenase deficiency

A 34-year-old man presented with acute hemolytic anemia secondary to acute viral hepatitis A and a coexisting acute cytomegalovirus infection. This association has not been described previously in patients with glucose-6-phosphate dehydrogenase deficiency and is the subject of this report.

Role of serum angiotensin converting enzyme in sarcoidosis

This study was conducted to determine the role of Serum Angiotensin Converting Enzyme (SACE) as a marker in the differential diagnosis of pulmonary diseases and prognosis of sarcoidosis. A retrospective analysis of 113 medical records of patients at The Aga Khan University Hospital, with laboratory investigation for SACE was performed. Among 113 patients, 51 cases were found to have sarcoidosis, 44 of them had SACE levels greater than 52 IU/L (mean ACE 104.44). SACE levels were also found elevated in other clinical conditions like tuberculosis (mean 58.64 IU/L), but the enzyme level were less (p 0.04) than those found in sarcoidosis (mean (92.97 IU/L). SACE activity was found to be considerably lower in other chronic lung diseases such as, fibrosing alveolitis (mean 43.98 IU/L), interstitial lung disease (mean 42.11 IU/L) and chronic obstructive lung disease (mean 40.85 IU/L). Twenty patients of sarcoidosis, who received steroid treatment subsequently showed a decline in the SACE levels. SACE is a useful marker in differential diagnosis as 37.2% cases of sarcoidosis compared to only 9.09% of tuberculosis had SACE levels greater than 100 IU/L. In addition, our data also suggest that serum ACE is useful for the diagnosis as well as monitoring prognosis in sarcoidosis.

Duodenal erosions and ulcers in patients with pancreatobiliary obstruction

In order to determine whether obstructive pancreatobiliary lesions increase the risk of duodenal erosions and ulcers, the duodenal mucosa of patients with these lesions were prospectively examined before endoscopic retrograde cholangiopancreatography (ERCP). During the study period, 133 patients underwent ERCP for various reasons in the Department of Medicine, The Aga Khan University Hospital. One hundred and twenty-three patients were eligible for final analysis. Sixty-five patients with bilirubin > or = 35 mumol/L and alkaline phosphatase > or = 2.5 times normal levels along with radiological evidence of pancreatobiliary obstruction were included in the obstruction group. Fifty-eight patients who did not fulfil these criteria were used in the control group. Acid peptic lesions, which included erosions and ulcers, were seen in 16 patients of the obstruction group and four patients of the control group (P = 0.016, odds ratio (OR) = 4.41). Patients with carcinoma of the pancreas had a greater number of lesions than the rest of the obstruction group (P = 0.001, OR = 8.75). Individual variables like age, sex, serum bilirubin, alanine aminotransferase, alkaline phosphatase, amylase levels, and duration of jaundice did not increase the vulnerability to acid peptic injury. The degree of obstruction multiplied by duration of jaundice (alkaline phosphatase x days) increased the susceptibility for duodenal disease (P = 0.047). From this data it was concluded that patients with obstructive pancreatobiliary lesions are more prone to acid peptic duodenal lesions.

The use of fine needle aspiration biopsy in the management of thyroid disease

Fine needle aspiration biopsy is now a first line investigation in thyroid disease. The purpose of this study was to evaluate the results of this technique in comparison with routine histopathology. A total of 593 aspirations over a four year period were included. There were 390 (65.7%) solitary nodules, 124 (20.9%) multinodular goiters, 66 (11.1%) diffuse goitres and 13 (2.2%) recurrent post thyroidectomy nodules. Radioisotope scanning in 386 cases showed 325 (84.2%) cold nodules, 54 (14.0%) warm nodules and 7 (1.8%) hot nodules. There were 458 (77.2%) colloid goitres and cysts, 14 cases of thyroiditis (2.2%) and 30 malignancies diagnosed on fine needle aspiration biopsy. In 19 cases (3.2%) a diagnosis of follicular neoplasm and in 29 cases (4.9%) a diagnosis of suspicious aspirate was made. Histological results were available in 176 cases. In 108 cases findings of histology and FNAB were compared with radioisotope scanning. A sensitivity of 92.8% and 42.8%, a specificity of 90.1% and 98.7% and accuracy index of 90.3% and 94.3% was found, when considering suspicious cases alternatively as positives and negatives. Surgery was recommended in all suspicious cases to prevent reduction in sensitivity of the technique. Fine needle aspiration biopsy was found to be a highly effective procedure which can obviate a lot of unnecessary surgery in thyroid lesions.

Carbohydrate moiety of Plasmodium falciparum glycoproteins: the nature of the carbohydrate-peptide linkage in the MSP-2 glycoprotein

Metabolic labelling of Plasmodium falciparum parasites with [3H]GlcN, [3H]Man, [3H]Gal and [3H]ethanolamine, and subsequent purification by SDS-PAGE of the labelled material provided effective labelling of the MSP-1, 195 kDa, and MSP-2, 42-53 kDa, glycoproteins. Reductive beta-elimination of the MSP-2 released from the gel consisted of glycopeptides containing labelled sugars. Processing of the eliminated components and identification of the sugar residues demonstrated the presence of N-acetylglucosaminitol and N-acetylgalactosaminitol amongst other labelled sugars. Reductive beta-elimination with sodium hydroxide-sodium borotritide-borohydride showed the presence of glucosaminitol and alanine in the hydrolysis products. The MSP-2 was retained on solid phase wheat-germ agglutinin and was released from the lectin by treatment with GlcNAc. Upon treatment with O-glycanase the MSP-2 glycoprotein released labelled amino sugar, and derived oligosaccharides on treatment with exoglycosidases released labelled components corresponding to the metabolically incorporated sugars. Labelled Gal was incorporated into the MSP-2 glycoprotein using [3H]UDP-Gal and galactosyltransferase. The galactosylated glycoprotein released labelled Gal upon treatment with beta-galactosidase. The results of the present study suggest that the carbohydrate chains of the MSP-2 glycoprotein are attached to the protein backbone via GlcNAc- and GalNAc-serine/threonine in O-glycosyl linkage and the glycoprotein has terminal GlcNAc and Gal residues. The carbohydrate moieties of MSP-2, glycoprotein consist mainly of short chains linked to the protein core.

Recurrent myocardial infarction with patent coronary arteries

Two separate episodes of severe chest pain occurred several years apart in a 25-year-old male patient with typical clinical findings of acute myocardial infarction with each episode. Cardiac catheterization following the second infarction confirmed the presence of myocardial dysfunction with apical akinesis and dyskinesis. Both coronary arteries were radiologically patent; however, there was evidence of probable recanalization of the right coronary artery. Several months later, the patient developed flank pain, hematuria, progressive renal failure, and cardiac decompensation, and died with intractable arrhythmias. At autopsy, a large apical mitral thrombosis was found and was the presumptive source of multiple systemic emboli.

A profile of 100 complicated cases of chronic suppurative otitis media

A two year study of cases of chronic suppurative otitis media admitted in the Ear, Nose and Throat (ENT) Department of Sir Salimullah Medical College and Mitford Hospital from January 1991 to December 1992 was done. 112 patients of chronic suppurative otitis media (CSOM) were admitted during this two year period, out of which 100 patients (89.3%) presented with different types of complications and only 12 patients (10.7%) presented with no complications. Factors associated with the late presentation of the disorder, including poor socioeconomic conditions and lack of hospital facilities, are identified. Measures to prevent the rate of complications and hearing loss in children are suggested.

Prevalence of Epstein-Barr viral sequences and EBV LMP1 oncogene deletions in Burkitt's lymphoma from Pakistan: epidemiological correlations

To investigate the potential relationship of socioeconomic status with the prevalence of Epstein-Barr virus (EBV) and to understand the significance of del-LMP-1 within EBV+ cases of Burkitt's lymphoma (BL), we studied 10 cases of BL, 30 cases of diffuse large cell lymphoma (DLCL) arising in nonimmunocompromised patients, and 30 reactive tonsillar biopsy specimens from Pakistan. Each lymphoma was analyzed for EBV by EBER1 RNA in situ hybridization (EBV-RISH). Cases showing hybridization signal within neoplastic cells and all reactive tonsillar tissues were analyzed for EBV strain type by EBNA-2 polymerase chain reaction (PCR) and for the presence of a del-LMP-1 by PCR. Eight of 10 (80%) of BL were EBV+, each containing EBV strain A and a wild-type LMP-1 gene. In contrast, only 4 of 30 DLCL (13%) cases were EBV positive (three strain A, one strain B), each containing a wild-type LMP-1 gene. Fifteen of 30 tonsillar biopsy specimens contained EBV, all of which were strain A and wild-type for LMP1. The prevalence of EBV in BL from Pakistan is slightly lower than in BL in endemic regions, but significantly higher than in BL in North America. EBV positivity probably reflects the socioeconomic status of the patient population and age at seroconversion. The absence of del-LMP-1 within all EBV+ BL cases is consistent with the view that del-LMP-1 is not involved in the pathogenesis of BL, and the presence of del-LMP-1 in EBV+ cases of BL reported in other studies may likely reflect the prevalence of a viral strain containing the 30-bp deletion within the respective population studied.

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in amoebic liver abscess

We report here three cases of amoebic liver abscess with biochemical abnormalities of syndrome of inappropriate secretion of antidiuretic hormone (SIADH). All three patients were febrile and had pain in the right upper abdomen radiating to the right shoulder. Liver function tests were disturbed. Chest X-ray showed raised right hemidiaphragm with obliteration of the right costophrenic angle. On ultrasound, an abscess 710 cm in diameter was located in the upper right lobe. SIADH was transient and improved with treatment. We believe this to be the first reported association of SIADH with amoebic liver abscess.

A double-blind crossover study in moderately hypercholesterolemic men that compared the effect of aged garlic extract and placebo administration on blood lipids

A double-blind crossover study comparing the effect of aged garlic extract with a placebo on blood lipids was performed in a group of 41 moderately hypercholesterolemic men [cholesterol concentrations 5.7-7.5 mmol/L (220-290 mg/dL)]. After a 4-wk baseline period, during which the subjects were advised to adhere to a National Cholesterol Education Program Step I diet, they were started on 7.2 g aged garlic extract per day or an equivalent amount of placebo as a dietary supplement for a period of 6 mo, then switched to the other supplement for an additional 4 mo. Blood lipids, blood counts, thyroid and liver function measures, body weight, and blood pressure were followed over the entire study period. The major findings were a maximal reduction in total serum cholesterol of 6.1% or 7.0% in comparison with the average concentration during the placebo administration or baseline evaluation period, respectively. Low-density-lipoprotein cholesterol was also decreased by aged garlic extract, 4% when compared with average baseline values and 4.6% in comparison with placebo period concentrations. In addition, there was a 5.5% decrease in systolic blood pressure and a modest reduction of diastolic blood pressure in response to aged garlic extract. We conclude that dietary supplementation with aged garlic extract has beneficial effects on the lipid profile and blood pressure of moderately hypercholesterolemic subjects.

Efficacy of octreotide in diarrhoea due to Vibrio cholerae: a randomized, controlled trial

Although octreotide, a long-acting analogue of somatostatin, is currently used in the treatment of chronic secretory diarrhoea due to various causes, its role in the management of acute secretory diarrhoea is not well established. In the present study, therefore, the therapeutic value of octreotide in the management of cholera, a classical example of acute secretory diarrhoea, was investigated. During an outbreak of cholera, patients admitted with acute secretory diarrhoea of < or = 24 h duration and a purging rate > 100 ml/h were enrolled on the study and randomly assigned to octreotide (N = 17) and control (N = 16) groups. All 33 patients received intravenous fluid replacement and antibiotic treatment (200 mg ofloxacin twice daily for 3 days, by mouth). Each patient in the octreotide group was also given a subcutaneous injection containing 100 micrograms octreotide every 8 h for a maximum of six doses. The stool output of each patient was recorded every hour until there had been none for an hour, which was taken as the endpoint. Mean (S.D.) total stool output was lower [6.56 (3.7) v. 9.7 (6.5) litres] and the mean (S.D.) duration of diarrhoea after admission was shorter [32.9 (15.6) v. 47.8 (22.3); P < 0.05] in the octreotide group than in the control group. However, as both groups generally had similar purging rates, the higher volume of stools from the control group was simply the result of the longer period of diarrhoea in this group. Octreotide therefore only decreased the duration of diarrhoea in the cholera patients.

Trace element nutrition in developing countries

Trace element status in humans is often poorly established in developed, let alone developing, countries. There have been assumptions about inevitable adequacy, especially for ultra-trace elements, like chromium, with varied diets. However, new pressures on trace element adequacy are emerging, like developments in food technology with the new formulated foods and element pollutants (toxic metals) with potential interactions with essential elements. Improved, more sensitive methods for trace element measurements in foods and biological specimens, functional indices of trace element status, with application to nutritional epidemiology, and the pursuit of clinical trials, should allow appropriate revision of current views. This process is likely to more consequential in developing countries.

Clinicopathological features and management of immunoproliferative small intestinal disease and primary small intestinal lymphoma in Pakistan

This study was performed to confirm the existence of immunoproliferative small intestinal disease (IPSID) in Pakistan. Clinicopathological features of 12 patients with histologically confirmed disease were analysed. Patients were mostly young males with median age of 24.6 years. Two thirds belonged to poor socioeconomic class. Main presenting features were chronic diarrhoea and weight loss. Eleven patients had radiologic evidence of malabsorption syndrome. Endoscopic findings of mucosal thickening, edema, and flattened villi were present in the majority. Patients had both secretory and non-secretory types of disease. Six patients presented with stage A disease. Four responded to antibiotics or steroids, although mucosal abnormalities persisted in three. Two stage A patients evolved into stage C disease, one was lost to follow-up, the other is alive with disease. Three patients presented with stage B disease. Two responded completely to chemotherapy, the third refused treatment and expired after 16 months. Three patients had stage C disease at diagnosis. They received aggressive combination chemotherapy and remain in complete remission with a median follow-up of 2.2 years. This is the first series of patients with IPSID reported from Pakistan. Clinicopathological features and therapeutic results are consistent with the experience elsewhere. Increased awareness may result in early diagnosis and better management.

Comparison of liver histology in chronic active hepatitis C and chronic active hepatitis B

OBJECTIVE

To study the histological features of chronic active hepatitis C (CAH-C) and to compare these with those of chronic active hepatitis B (CAH-B).

METHODS

Thirty-two liver biopsy specimens from patients with chronic active hepatitis and presence of antibodies to hepatitis C on second generation enzyme immunoassay were studied and compared with those in 34 patients with CAH-B. Seventeen of the 32 CAH-C patients had fully developed or developing cirrhosis of liver whereas the remainder had only chronic active hepatitis.

RESULTS

Among 32 patients with CAH-C, fatty change (20), Kupffer cell hyperplasia (30), sinusoidal lymphocytosis (27) lymphoid follicles aggregates in portal tracts (26) and bridging necrosis (16) were regular features. Focal necrosis, bile duct necrosis, cholestasis and ground glass cells were however seen much less often. On the other hand, in patients with CAH-B, fatty change (no patient), sinusoidal lymphocytosis (one patient) and lymphoid follicles/aggregates in portal tracts (one patient) were rare. Also, Kupffer cell hyperplasia (22 patients) was seen less commonly in patients with CAH-B as compared to CAH-C. Focal necrosis (34 patients), bile ductular proliferation (9 patients), cholestasis (17 patients) and ground glass cells (15 patients) were more prominent in CAH-B.

CONCLUSION

Presence of certain histological features can help in distinguishing between CAH-C and CAH-B.

Barrett's oesophagus and Helicobacter pylori

In order to demonstrate the presence of Helicobacter pylori in the metaplastic epithelium of Barrett's oesophagus and to evaluate its possible association with this entity, we examined 29 cases of Barrett's oesophagus where concomitant antral biopsies were also available. These cases were compared with an equal number of age and sex matched controls of uncomplicated reflux oesophagitis. H. pylori was present in 11 of 29 cases of Barrett's oesophagus (38%). No increase in the frequency of H. pylori antral gastritis was found in patients of Barrett's oesophagus compared to the control group of uncomplicated reflux oesophagitis. The positivity of Barrett's oesophagus for H. pylori correlated with the presence of H. pylori antral gastritis (P < 0.05), although in two cases of H. pylori-positive Barrett's oesophagus antral biopsies were negative for H. pylori. No difference was found in the severity of inflammatory and dysplastic changes of H. pylori-positive and H. pylori-negative Barrett's oesophagus. Presence of H. pylori does not seem to alter the natural history of Barrett's oesophagus.

The value of fine needle aspiration biopsy in the management of breast disease

Fine needle aspiration biopsy is a technique used all over the world in the diagnosis and management of breast lumps. It is safe, quick, accurate, cost effective and acceptable to the patients. We reviewed 234 fine needle aspiration biopsies performed over a period extending from 1991-1993 for diagnosis of breast lesions. Majority of the patients presented with breast lumps (89.7%). On FNAB 144 (61.4%) cases were reported as benign and 60 (25.6%) as malignant. Histological diagnosis was available in 116 cases. On comparison with open biopsy diagnosis, FNAB was found to have a sensitivity of 96.4%, a specificity of 95.5% and efficiency rate of 96.2%. The results of the study endorse the use of FNAB as an accurate and effective technique in the management of breast ailments in our set-up.