Preparation and characterization of a new polymorphic form and a solvate of glibenclamide

A new crystalline form and a solvate of glibenclamide were prepared and characterized by hot-stage microscopy, DSC, IR, scanning electron microscope, X-ray powder diffraction and dissolution studies. From I, III and the solvate which melt at 174.4, 153.2 and 109.3 degrees C, were obtained by crystallization. Significant differences between the three forms in the X-ray and IR spectra were observed. Polymorphic transformation was observed for the least stable form (III) to the most stable one (form I) upon storage at different temperatures and trituration. The dissolution profiles showed significant differences between the three forms, with form III having the highest dissolution rate.

Dissolution kinetics of glibenclamide glass

This work examines the dissolution kinetics of glibenclamide crystalline state, form I, and glibenclamide glassy state, form II. This required determination of the pH-solubility profiles of the two forms, dissolution at different stirring rates, temperatures, and pHs. It was found that form II exhibited higher solubility and dissolution rate at all the studied pHs. However, a significant increase in dissolution and solubility of form II was noted at pH 6. Dissolution studies at different stirring rates confirmed that the dissolution process is diffusion controlled, zero order in nature and adheres to the Noyes and Whitney and Levich equations. Dissolution studies at different temperatures enabled calculation of the heat of dissolution, Ea, of both forms. Ea for form I and form II was found to be almost identical. Storing of form II for one week at different temperatures resulted in the partial transformation of form II to form I as indicated from dissolution studies. The extent of transformation and hence reduction in dissolution rate increased with the increase in storage temperature.

Pattern of postoperative pyrexia in Khartoum

The pattern of postoperative pyrexia in Khartoum was prospectively studied in 260 patients who underwent a variety of surgical operations. Ninety four patients (36.1%) developed postoperative pyrexia. The commonest causes of pyrexia encountered were wound sepsis (10%), malaria (9.6%) and respiratory tract infection (7.3%). Less frequent causes were urinary tract infection, thrombophlebitis, intra-abdominal sepsis and deep vein thrombosis. In 14.6% of the patients, the cause of pyrexia was undetermined. The risk factors for postoperative pyrexia were the patient's age, diabetes mellitus, obesity, preoperative chest infection, smoking, duration of surgery, operator's surgical experience and urethral catheterisation. The postoperative pyrexia was associated with 7.4% mortality rate which was due to intra-abdominal sepsis and pulmonary embolism. The incidence of postoperative pyrexia can be minimised by adequate preoperative preparation, meticulous surgical technique and good postoperative care.

Schistosomal glomerulopathy: a putative role for commonly associated Salmonella infection

A total of 190 patients were selected after being subjected to hemoculture for detecting Salmonella spp, coproscopy for Schistosoma mansoni eggs and ELISA testing for anti schistosomal sero-reactivity. They made up 4 group; The first comprised 31 febrile patients with positive hemoculture, coproscopy and ELISA, 13 of them with hepatic fibrosis and received combined anti- typhoid and antibilharzial therapy. The second comprised 53 febrile patient with the same criteria; 18 with hepatic fibrosis, and received anti typhoid & antibilharzial alternatively. The third group comprised 46 febrile patients with positive hemoculture and negative coproscopy but with positive ELISA 20 were hepatosplenic & received anti typhoid treatment. The fourth comprised 60 afebrile patients with negative hemoculture and positive coproscopy and ELISA 35 were hepatosplenic, and received anti-bilharzial treatment. 50 healthy individuals were selected as control. The controls and the patients; before and after treatment underwent investigation for determining levels of serum complement3 as a marker of immune complex precipitation activity and creatinine clearance, and urinary proteins excretion in 24 hours as measurements of glomerular function. The specific treatment either combined or alternative or single in the first 3 groups consequently showed marked improvement in the above criteria with insignificant additive pattern in the second. The fourth group showed non-significant difference in the above criteria after anti-bilharzial therapy among the hepatosplenic, meanwhile it improved these criteria significantly among the non-hepatosplenic--in the four groups--whose criteria were significantly higher than among the hepatosplenic before treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal tuberculosis

The abdomen is involved in 10% to 30% of patients with pulmonary tuberculosis. The diagnosis is not difficult in societies where the disease is common and clinicians are aware of it. While previously rare in Western countries, the incidence is now rising among immigrants, and patients with AIDS. In HIV-infected patients, the disease is of a rapidly progressive nature, often fatal through usually treatable, but the diagnosis is difficult and often delayed. Treatment is essentially medical but occasionally surgical operation is necessary.

Knowledge of sexually transmitted diseases, HIV infection and AIDS among sexually active adolescents in Nairobi, Kenya and its relationship to their sexual behaviour and contraception

A total of 675 male and female adolescents, aged 10 to 19 years, who were attending the adolescent antenatal clinic at the Kenyatta National Hospital and the Special STD and Skin Disease Clinic in Nairobi, between April 1, 1991 and July 31, 1991, were interviewed by means of partially structured questionnaire, to determine their level of awareness on sexually transmitted diseases, HIV infection, AIDS and contraception with its relationship to their sexual behaviour and contraceptive practice. Adolescents formed 27.6% of people attending the STD and Skin diseases clinic, of whom 52.9% were females and 41.2% were males. Majority of them were not in any formal employment. A few were students in schools in the city. 70.4% of the total group mentioned gonorrhoea as a sexually transmitted disease, as compared to only 54.3% who mentioned AIDS as a sexually transmitted disease. They only mentioned three diseases, namely gonorrhoea, syphilis, and AIDS (HIV infection). Majority of them had started coitus very early. They were involved with many and different partners, some of whom belonged to the high risk groups for HIV infection as well as STD's. As a reflection of their low awareness on AIDS, most of these sexually active adolescents had not changed their sexual behaviour, nor were they using any protective measure against STD's or HIV infection. The implications of these findings are discussed and possible remedial measures suggested.

Synthesis and evaluation of 1-[11C]methyl-4-aryl-piperazinium salts as myocardial imaging agents

Our previous study with radioiodinated 1-methyl-1-(2-hydroxyethyl)-4- phenylpiperazinium derivatives indicated that these compounds localize selectively in the rat myocardium. Based upon these results, 1-[11C]methyl-1-alkyl-4-phenylpiperazinium cations were synthesized and evaluated for their potential as myocardial imaging agents. Biodistribution studies were performed in rats and imaging studies in normal dogs. The results indicate high concentrations of 3-4% ID/g in the rat heart at 5 min, comparable to those obtained with the radioiodinated analogs. Sequential imaging of the canine heart showed a similar pattern of uptake. The level of activity reached at 20 min was maintained over the 1-h time period. These results suggest that the phenylpiperazinium agents may have potential application as myocardial imaging agents.

Isolation and characterization of simian immunodeficiency virus from African white-crowned mangabey monkeys (Cercocebus torquatus lunulatus)

Forty-eight of 236 sera from seven species of African non-human primates in Kenya, including those of white-crowned mangabey monkeys (Cercocebus torquatus lunulatus) had antibodies to simian immunodeficiency viruses (SIVs). Isolates of simian lentivirus were obtained from seropositive white-crowned mangabey monkeys which are indigenous in West Africa. This virus, designated as SIVWCM, appeared morphologically similar to HIV by electron microscopy, showed Mg(2+)-dependent reverse transcriptase activity, and induced cytopathic effects in human CD4-positive cells. Western blotting analysis revealed that env products of SIVWCM cross-reacted with those of SIVAGM more strongly than with those of HIV-1 and SIVMAC, and clear hybridization bands were detected with an SIVAGM probe. For comparison of the virus sequence with those of other primate lentiviruses, part of the pol gene and the long terminal repeats (LTRs) were amplified and cloned. Sequencing showed that SIVWCM isolates were closely related to SIVAGM isolates. This study suggested that SIVAGM from the Cercopithecus genus and SIVWCM from the Cercocebus genus may be members of an SIV group that is genetically distinct from the SIV from a sooty mangabey monkey (SIVSMM) of the genus Cercocebus, to which the white-crowned mangabey monkey also belongs.

Mycetoma

Mycetoma is a chronic infective condition of tropical and subtropical regions. It is commoner in males, especially those in their third or fourth decade who work on the land. The clinical triad of subcutaneous nodule, sinuses and discharge usually leads to diagnosis; the disease is commonly painless. Treatment is by extensive surgical excision of affected areas and may include limb amputation. Recurrence is common, rates ranging from 20 to 90 per cent. Medical treatment may be used on its own or as an adjunct to surgery. Although such therapy may cure over half of those with actinomycetoma (caused by bacteria, mainly aerobic actinomycetes), those affected by eumycetoma (caused by fungi) have a poorer prognosis and may require many years of drug therapy.

Oesophageal varices in a region of the Sudan endemic for Schistosoma mansoni

In a field study of two villages in the Gezira, an area of the Sudan endemic for Schistosoma mansoni, liver ultrasonography was used to detect subjects with Symmers' hepatic periportal fibrosis, some of whom underwent oesophagoscopy to detect oesophageal varices. The prevalence of oesophageal varices in subjects undergoing oesophagoscopy was 54 per cent and 67 per cent respectively, occurring mainly in males aged about 30 years. The varices were usually asymptomatic. Symptomatic varices (with a positive history of haematemesis) occurred in 4 per cent and 3 per cent respectively of subjects with sonographic evidence of liver periportal fibrosis. By detecting oesophageal varices in an asymptomatic phase, hepatic ultrasonography and fibreoptic oesophagoscopy may elucidate the natural history of the varices and their response to periodic anti-schistosomal chemotherapy.

Consideration on some hormone binding proteins patterns during pregnancy

Serum concentrations of sex hormone binding globulin, transcortin, thyroxine binding globulin, transthyretin together with retinol binding protein, ceruloplasmin, transferrin and albumin were measured sequentially in pregnant women in order to derive more definite suppositions relating to the prime function of hormone binding proteins. Thus, the fact that except for transthyretin all other specific hormone binding proteins exhibited appreciable but significantly variable increases would suggest: a) the apparent existence of more complex mechanisms regulating protein metabolism during pregnancy than hitherto postulated (i.e. the general notion of an integrated estrogen influence); b) a major and distinctive role for each of the hormone binding proteins is plausible since alterations in hormonal requirements by the fetus as pregnancy progresses can not be provided by the almost constant transplacental transfer rate of the "free" hormone moiety.

Effect of oral activated charcoal on the pharmacokinetics of quinidine and quinine administered intravenously to rabbits

The pharmacokinetics of quinidine and quinine following intravenous administration (10 mg/kg) with and without concurrent treatment with oral activated charcoal was studied in the rabbit. Marked differences were observed in the pharmacokinetic parameters. Compared to quinidine, quinine was characterized by larger volume of distribution (Vd), systemic clearance (Cl) and elimination rate constant (Kel), and smaller half-life of elimination (t1/2), mean residence time (MRT) and area under the curve (AUC). Activated charcoal administered orally (15 g) significantly decreased the serum concentrations of quinidine but not quinine. Furthermore, charcoal treatment significantly enhanced the systemic elimination of quinidine as indicated by the significant increase in Cl and decrease in t1/2, MRT and AUC. By contrast, activated charcoal had no significant effect on the pharmacokinetic parameters of quinine. Differences between quinidine and quinine in respect to the effect of activated charcoal on the systemic elimination of these drugs seem at least, in part, dependent on dispositional factors. The high Cl and Vd of quinine in the rabbit are probably factors that mask the effect of charcoal on the elimination of this drug.

Free amino acids, copper, iron and zinc composition in sera of patients with thyrometabolic diseases

Free amino acids together with copper, iron and zinc were measured in sera of 67 adult patients with thyrotoxicosis (n = 29) or hypothyroidism (n = 38). In contradistinction to the almost indifferences exhibited by the three metals, many amino acids displayed significant relationships with the thyrometabolic activity (mainly tyrosine and arginine with r values of 0.5 and 0.44, respectively). Additional analyses revealed certain patterns, between trace metals and amino acids, which conferred challenging difficulties to interpretation. Thus while zinc was associated positively with some amino acids (such as glutamic acid and alanine), copper correlated almost invariably in a negative manner with citrulline, alpha-amino-butyric acid, proline, glycine and valine. This new information should contribute to our knowledge of the complex metabolism of both trace metals and amino acids.

Utilization of a computer-controlled laboratory workstation (Biomek 1000) in routine radioimmunoassay laboratory

The suitability and performance characteristics of a recently introduced computer-controlled laboratory workstation (Biomek 1000) for use in automating sample transfer and reagent additions in radioimmunoassay techniques were assessed. The system is based on the use of disposable tips and, therefore, reduces any possible sample carry-over and eliminates the need for priming with the subsequent reduction in cost of reagents. However, the machine lacks the useful option of liquid-level sensing facility. Acceptable technical performance in terms of precision, accuracy and throughput was obtained with the Biomek 1000 which complied with international recommendations on the safety of hospital laboratory equipment.

Ureteral triplication (type I) with vesicoureteral reflux

Complete triplication of ureter associated with vesicoureteral reflux successfully treated with ureteroureterostomy is described. The principle of the Weigert-Meyer law applies to complete triplication of the ureter.

Physico-chemical characterization of a new salt of ibuprofen

A new salt of ibuprofen was prepared by reaction with t-butylamine; its formation was confirmed by IR and 1H-NMR spectroscopy. The salt was characterized by thermoanalytical, X-ray powder diffraction and solubility studies. The salt was found to be 1.5 times more soluble in water than was ibuprofen, with an enthalpy of solution of -8.84 kcal mol-1.

Fournier's gangrene in Khartoum

Nine patients with Fournier's gangrene are presented and the relevant literature is reviewed. Fournier's gangrene is secondary to other predisposing conditions, the commonest causes being urethral and perianal sepsis. Local excision and antibiotics are the treatment of choice.

Metronidazole prophylaxis in acute mural appendicitis: failure of a single intra-operative infusion to reduce wound infection

The efficacy of a single 500 mg intravenous intra-operative dose of metronidazole in the prevention of postoperative wound infection, following appendicectomy for acute mural appendicitis, was studied in a prospective randomized placebo controlled trial. Fourteen of the 96 patients (14.6%) in the metronidazole group and 13 of the 94 in the placebo group (13.8%) developed postoperative wound infection. Late sepsis was noted in 4 out of the 96 patients in the metronidazole group and in one of the 94 patients in the placebo group. This study suggests that a single intra-operative dose of metronidazole dose not reduce the incidence of postoperative wound infection following appendicectomy for acute mural appendicitis.