Effect of Khat chewing on the bioavailability of ampicillin and amoxycillin

The study examined the effect of Khat chewing on ampicillin and amoxycillin bioavailability following the administration of a 500 mg single dose of each antibiotic at different times relative to Khat chewing. Using a urinary excretion method the bioavailabilities of ampicillin and amoxycillin were determined in eight healthy adult male Yemeni volunteers. The extent and rate of ampicillin bioavailability were reduced significantly by Khat chewing except when administered 2 h after the Khat chewing session. However, the bioavailability of amoxycillin was only significantly reduced when the antibiotic was taken midway through the Khat chewing session. It was concluded that the two antibiotics, particularly ampicillin, should be taken 2 h after Khat chewing.

Neonatal meningitis in northern Jordan

A two-and-a-half year prospective study of neonatal meningitis in the two main referral hospitals in Northern Jordan was carried out to determine the clinical spectrum and particular characteristics of meningitis in the newborn. The 53 cases studied represented an incidence of 1.1 per 1000 live births. The commonest bacterial pathogen isolated was Klebsiella species (40 per cent) followed by Enterobacter (19 per cent). The mortality rate and neurological sequelae among surviving children were 32 and 39 per cent, respectively, with higher rates among preterm/low birth weight and early onset meningitis groups. Of the presenting clinical features, there was a highly positive association between two risk factors and outcome. A bulging anterior fontanelle was the only significant predictor of mortality (P = 0.009) and altered sensorium was the only predictive of post-meningitis sequelae (P = 0.016). The need to recognize that Klebsiella species is an increasingly important pathogen; cefotaxime or ceftazidime plus ampicillin are the most appropriate antibiotics to be used initially, and continuous surveillance thereafter have been stressed.

Hazard analysis and critical control point evaluation of school food programs in Bahrain

Hazard analyses were conducted in six food preparation sites and 16 school canteens in the State of Bahrain. Sandwiches made with cheese, meat, eggs, liver, and beef burgers were prepared in small shops or a bakery outside schools. Foods were cooked between 4 and 5 A.M. Time-temperature exposure during cooking was adequate to kill vegetative microbes and their spores, but potential for recontamination existed from the hands of food workers, utensils, and cloths and sponges used for wiping. All foods were left at room temperature before they were transported in vans to schools where they were also kept at room temperature between 17 degrees C and 41 degrees C. Air temperature inside the canteens during this investigation was between 18.5 and 28 degrees C with a relative humidity of 65 to 70%. Hazard analyses, which included observation of operations inside school canteens and sites of food preparation, measuring temperatures, and interviewing workers and consumers (teachers, students) were carried out. Hazards were primarily associated with preparation of foods long before they were consumed, physical touching of products, and holding foods at room temperature after preparation. Holding foods at room temperature would have allowed germination of bacterial spores and multiplication of microbes. Reheating of foods was not practiced. Health promoters must be aware of these hazards and need to educate food workers, administrators, and the public on the methods of prevention.

The role of heparin-binding growth-associated molecule (HB-GAM) in the postsynaptic induction in cultured muscle cells

The heparan sulfate proteoglycan (HSPGs) is a components of the extracellular matrix of skeletal muscle that is concentrated at the neuromuscular junction (NMJ). Recent studies have suggested that HSPG, together with its bound peptide growth factors, plays important roles in autocrine or paracrine types of regulation of cell growth and differentiation. Heparin-binding growth-associated molecule (HB-GAM; also known as pleiotrophin, or p18) is a newly discovered HSPG-bound factor that is expressed at high levels in the developing CNS and PNS. In this study, we examined the role of this factor in NMJ development by examining its relationship to the formation of ACh receptor (AChR) clusters. Using an antibody against recombinant rat brain HB-GAM, we found that this protein is present prominently on the surface of cultured Xenopus myotomal muscle cells by immunocytochemistry. It is associated with HSPGs as evidenced by the fact that heparin and heparinase treatment greatly diminished the antibody labeling. HB-GAM is concentrated at preexisting AChR hot spots as well as at those induced by polystyrene beads. In addition, this molecule is also concentrated at AChR clusters induced by spinal cord neurons in nerve-muscle cocultures. To assess its function in synaptic induction, we applied recombinant HB-GAM-coated beads to cultured muscle cells to effect its focal presentation. Over 70% of these beads induced the formation of AChR clusters as shown by fluorescent alpha-bungarotoxin labeling. Furthermore, bath application of HB-GAM inhibited the nerve-induced formation of AChR clusters. Thus, HB-GAM is an endogenous muscle-derived factor that may be a component of the molecular mechanism in postsynaptic induction.

Lactic acidosis and renal enlargement at diagnosis and relapse of acute lymphoblastic leukemia

Bilateral renal enlargement was noted on ultrasonography during an extensive renal evaluation for severe hypokalemic metabolic acidosis with an increased anion gap in a 12-year-old Hispanic boy who had normal results of a physical examination and complete blood count. The patient was found to have acute lymphoblastic leukemia. Resolution of the lactic acidosis and bilateral renal enlargement occurred with initiation of chemotherapy and recurred with each subsequent relapse.

Retinoblastoma gene product-associated proteins in human colon cancer cell lines

The expression of cellular proteins that associate with the human retinoblastoma (RB1) gene protein was examined in three colorectal carcinoma cell lines (SW480, SW403, DiFi) by immunoprecipitation analysis, using the mouse monoclonal antibody (RB-MAb-1) directed against the RB1 gene product (RB). The potential of RB-MAb-1 to detect RB-associated proteins by immunoprecipitation analysis was confirmed using three control cell lines (WI-38, J82, T24) known to express RB and/or RB-associated proteins. In all colon cancer cell lines tested, multiple RB-associated protein (RAP) bands were found with molecular weights of 30-50 kDa. Because involvement of the RB1 gene in colorectal tumorigenesis appears to differ from its role in other cancer types (wherein RB1 is lost or inactivated), it will be important to characterize the role of RAPs in RB growth regulatory mechanisms of colonic epithelial cells.

RB1 protein in normal and malignant human colorectal tissue and colon cancer cell lines

The pattern of human retinoblastoma (RB1) gene protein expression was directly examined in normal and malignant human colorectal tissues and in seven colorectal carcinoma cell lines by immunohistochemistry using the mouse monoclonal antibody (RB-MAb-1) directed against the retinoblastoma protein (RB). This is the first demonstration of RB immunostaining in adult human colonic epithelium and colorectal carcinomas. Specificity using RB-MAb-1 was confirmed by western blot analysis, which showed bands of 110-116 kDa corresponding to the sizes of unphosphorylated and phosphorylated RB. RB staining of normal adult colonic epithelium was confined to the nucleus and was most intense in the transitional zone of the crypt, whereas lumenal cells (fully differentiated) were RB negative. Primary colorectal carcinomas and all the colon cancer cell lines stained positively for nuclear RB, but the expression was heterogeneous with varying fractions of RB negative cells present. Because we and others have previously shown that loss or inactivation of the RB1 gene is infrequent in colorectal carcinomas, reduced RB expression in such cells is probably due to a cellular regulatory mechanism. For example, RB negative cells may be those in early-G1 phase (known to have reduced RB levels) or growth-arrested cells that have differentiated. The ability to directly detect RB in primary colorectal carcinomas will permit assessment of whether heterogeneous expression of the RB1 gene product has prognostic significance for survival of patients with this cancer.

The prognostic significance of positive CMV cultures during surveillance of renal transplant recipients

Renal transplant recipients are at risk of severe morbidity and mortality from CMV disease. We have undertaken routine surveillance for CMV shedding on 133 transplant recipients, using a rapid culture technique, in order to assess the incidence of CMV infection and disease in these patients and to assess the prognostic significance of detection in whole blood, throat swab specimens, or urine. Donor CMV seropositivity was associated with posttransplant CMV infection (P < 0.05) and disease (P = 0.06). CMV infection and disease were associated with the receipt of anti-T-cell antibodies (P < 0.0001 and P = 0.08, respectively). First shedding of virus from any site occurred earlier posttransplant in those recipients who developed disease (median 39 days) than in those who did not (median 55 days)(P < 0.05). Detection of virus in blood occurred at a median time of 16 days before onset of symptoms, compared with 9 days before symptoms in urine, and 3 days after onset of symptoms from throat swab. A positive blood culture represented a relative risk of 7.1 for the subsequent development of disease, compared with 2.1 and 1.8 for positive urine and saliva cultures, respectively. The addition of urine cultures to blood cultures increased the sensitivity for identification of those at risk--however, the relative risk was reduced to 5.8. We conclude that routine surveillance for CMV shedding, especially in blood and urine, can identify recipients at high risk of CMV disease, and propose a trial in which those with asymptomatic viremia are allocated to receive ganciclovir or placebo, in order to assess the efficacy of "preemptive" therapy in this group of patients.

Calcium set point progressively worsens in hemodialysis patients despite conventional oral 1-alpha hydroxycholecalciferol supplementation

Calcium set point was measured in 12 patients on chronic hemodialysis. Dialysate calcium concentration was 1.65 mmol/l. Calcium carbonate (CaCO3) was used as the phosphate binder and oral 1-alpha hydroxycholecalciferol (alfacalcidol) was administered in a dose of 0.25-1.0 micrograms/day for 12 months. Comparing base line and post study values, there were no significant changes in ionized calcium (ICa++), intact immunoreactive parathyroid hormone (iPTH), plasma total calcium (TCa++), plasma phosphate (P), alkaline phosphatase (ALP), or aluminum (Al). However, the relative calcium set point significantly worsened (shifted to the right). Three patients developed hypercalcemia (25%) with a total calcium > 2.65 mmol/l. Total bone mineral content (BMC) fell suggesting demineralization. We conclude that this dose of oral alfacalcidol, CaCO3, and a dialysate calcium concentration of 1.65 mmol/l are not sufficient to halt the progression of secondary hyperparathyroidism in chronic hemodialysis patients. Measurement of calcium set point may be the best early measure of failure to prevent worsening of hyperparathyroidism.

The effect of prenatal diagnosis on the incidence of Down syndrome livebirths in the Singapore General Hospital

During a 3-year-period between January 1988 and December 1990, there were 12 Down Syndrome (DS) livebirths out of 13,794 livebirths at the Department of Obstetrics and Gynaecology, Singapore General Hospital, giving an incidence of 1 in 1,150 livebirths or 0.87 per thousand. There were 1569 mothers who were 35 years or older at the expected date of delivery (EDD) and 5 of these 12 DS livebirths were from these older mothers. Although only 11.5% of all mothers were 35 years or more, as a group, these older mothers contributed to 42% of the DS livebirths. There were 5 DS fetuses diagnosed prenatally and 4 were aborted electively. The fifth DS fetus which was diagnosed prenatally was allowed to continue to term because of the mother's religious objection to an induced abortion. The failure to offer prenatal diagnosis and selective procreation to all mothers 35 years or older had resulted in 4 unnecessary DS births, reducing our DS detection rate by a factor of 33%. All these 4 cases were booked late for antenatal care.

Double-blind, placebo-controlled trial of human lymphoblastoid interferon prophylaxis of cytomegalovirus infection in renal transplant recipients

We have conducted a double-blind, placebo-controlled trial of human lymphoblastoid interferon prophylaxis of cytomegalovirus (CMV) infection in 74 renal transplant recipients. Interferon (3 x 10(6) units was given thrice weekly for the first 6 weeks, then twice weekly for a further 8 weeks. During the period of interferon therapy, the incidence of CMV excretion was lower in the interferon group (28% versus 50%, P = 0.065), mainly due to a significant reduction of CMV reactivation (9% versus 56%, P = 0.02). However, for the whole study period (including the follow-up period after interferon therapy), there was no difference in the incidence of CMV excretion (44% versus 53%). The onset of CMV excretion was delayed (8.2 +/- 0.8 to 20.9 +/- 5.5 weeks, P = 0.04). The duration of CMV excretion was also reduced (11.1 +/- 3.1 to 29.4 +/- 5.7 weeks, P = 0.008). The number of positive CMV isolates from urine and saliva was significantly less in the interferon group. There was no difference in the site of CMV excretion. Of the patients in the treatment group who excreted CMV, 43% developed disease as compared to 63% in the control group (difference not significant). There was also no significant difference in the severity of the CMV infection between the two groups. Benefit appears to be restricted to seropositive recipients of seronegative kidneys. The interferon regime used in this study was well tolerated, with mild fever being the only reported side-effect. No patient had to stop therapy because of toxicity. The incidence of rejection and graft loss was not different between the two groups.

Phase coherence of the middle-latency response in the elderly

We compared phase coherence of the auditory-evoked, middle-latency response (MLR) and the 40-Hz steady-state evoked potential (SSEP) in two groups of elderly listeners, matched for degree of audiometric hearing sensitivity loss. In group A, speech understanding was appropriate to the degree of audiometric sensitivity loss. In group B, speech understanding was disproportionately poor in relation to the degree of loss. In both modes of measurement (MLR and SSEP) phase coherence was significantly poorer in group B than in group A. In the case of MLR, maximum phase coherence was observed at the expected 40 Hz in group A, but at 30 Hz in group B. In the case of SSEP, maximum phase coherence was observed at 40 Hz in both groups but was poorer at almost all Fourier components in group B.

Studies on Balanites aegyptiaca fruits, an antidiabetic Egyptian folk medicine

An aqueous extract of mesocarps of the fruits of Balanites aegyptiaca exhibited a prominent antidiabetic activity by oral administration in streptozotocin induced diabetic mice. From one of the active fractions of this extract, two new steroidal saponins were isolated, and their structures were determined as 26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol 3-O-[alpha-L-rhamnopyranosyl-(1----2)]-[beta-D-xylopyranosyl-(1---- 3)]-[alpha-L-rhamnopyranosyl-(1----4)]-beta-D-glucopyranoside and its 22-methyl ether. In addition, two known saponins, 26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol 3-O-(2,4-di-O-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside and its methyl ether were isolated and identified. It was revealed that the individual saponins did not show antidiabetic activity, while the recombination of these saponins resulted in significant activity. From an ethanolic extract of the epicarps, two known flavonol glycosides, isorhamnetin-3-O-robinobioside and isorhamnetin-3-O-rutinoside were isolated and identified.

A study on intestinal helminths causing human anaemia in Cairo

Haematological and biochemical studies were done for 50 urban and rural Egyptians, from Cairo, suffering from Ancylostoma duodenale, Ascaris lumbricoides, Enterobius vermicularis, Hymenolepis nana, Schistoosma mansoni and Taenia saginata. Anaemia of varying degrees was noticed in all cases. The lowest Hb% and hematocrit value and highest eosinophilia were found in cases of ancylostomiasis with severe hypochromia compared with the other parasitic infections. Total blood protein was normal in all cases, except in 2 cases of S. mansoni, it was higher. Blood cholesterol and blood urea showed no deviation.

Oral contraceptives and the hemostatic system

We studied 30 control women and 131 pill users to evaluate effects of birth control pills and clinical factors on hemostasis. When control patients were matched with an equal number of pill users, none of the direct markers of activated hemostasis (fibrinopeptide A, platelet factor 4, and beta thromboglobulin) were increased. Plasminogen, prekallikrein, and protein C (protective against clotting) were significantly higher in pill users. Fibrinogen, antithrombin, alpha-2 antiplasmin, and fibronectin were comparable. Among the 131 pill users, antithrombin levels decreased with a family history of thromboembolism. Fibrinogen and fibronectin were increased with obesity, but there was no evidence of activated hemostasis. Overall, pill use did not appear to result in hypercoagulability. Considering family history of thromboembolism might further improve the safety of oral contraceptive use.