An automated aequorin luminescence-based functional calcium assay for G-protein-coupled receptors.

We describe in detail an automated and highly sensitive functional assay for calcium-coupled receptors (those receptors whose activation results in an increase in intracellular calcium levels) utilizing coelenterazine-charged aequorin as a probe for intracellular calcium levels ([Ca(2+)](i)). The assay was originally established to investigate Galpha(q)-coupled prostanoid receptors, which are members of the G-protein-coupled receptor (GPCR) superfamily, signaling through elevation of [Ca(2+)](i), initially focusing on the human EP(1) prostanoid receptor (hEP(1)). The parental human embryonic kidney cell line 293-AEQ17, developed by Button and Brownstein (Cell Calcium 14, 663-671, 1993), constitutively expresses apoaequorin and was used to develop a clonal cell line which stably coexpresses hEP(1). This cell line was used to optimize assay parameters in order to maximize accuracy and throughput in an automated 96-well format with the result that each 96-well plate can be completed in 70 min. Use of this flexible system will greatly simplify the functional analysis of GPCRs and other receptors which when activated result in increases in [Ca(2+)](i).

Visceral leishmaniasis in Gizan, Saudi Arabia.

Visceral leishmaniasis is endemic in southern Saudi Arabia. We prospectively evaluated 121 patients with visceral leishmaniasis at King Fahad Hospital in Gizan. All patients were infants and children. Seasonal variation was observed with more cases presenting in late spring and summer and few in winter. The predominant clinical features in these patients were chronic fever, abdominal distention, weight loss and hepatosplenomegaly. Lymphadenopathy was rare in contrast to African kala-azar. Common laboratory abnormalities included anemia, leukopenia, thrombocytopenia, hypoalbuminemia and hypergammaglobulinemia. Liver function tests were deranged in one-third of patients. Leishmania hemagglutination test was positive in all patients and all of them had positive bone marrow smear or culture for Leishmania donovani. Patients responded well to stibogluconate (Pentostam) therapy with a cure rate of 96.7%. Four patients died in the first few days of therapy. Jaundice and grossly deranged liver function tests were found to be bad prognostic signs.

Endoscopic removal of duodenal bruneroma.

A case of a pedunculated Brunner's gland hamartoma of the duodenum is presented. It was resected endoscopically with complete resolution of symptoms on long term follow-up. The pathological features of the tumour and the therapeutic approaches are discussed with particular reference to endoscopic resection.

Sensitivity of protein and RNA synthesis to emetine in axenic Entamoeba histolytica.

The action of emetine on the incorporation of (14C)1-DL-valine and (14C)-8-adenine in TCA insoluble fraction of axenic Entamoeba histolytica was investigated. These compounds were almost exclusively incorporated in the 'protein' and 'RNA' fractions, respectively. Incorporation of the purine showed a significantly higher sensitivity to emetine. While the percentage inhibition of valine incorporation by emetine decreased with increasing pH, the susceptibility of adenine incorporation was greater in the alkaline range.

Monitoring of drug therapy in epileptic children.

Twenty children who were receiving phenytoin either alone or in combination with phenobarbitone, were monitored for their plasma steady state levels. A wide interindividual variation was observed in steady state plasma levels. Among children who were receiving only phenytoin, nearly 50% had drug levels above 10 micrograms/ml. It was observed that children with drug levels above 10 micrograms/ml exhibited good therapeutic response. Two children who were presented with acute toxicity showed drug levels above 40 micrograms/ml. Children receiving combination of phenytoin and phenobarbitone showed extreme degree of variation in drug levels which was reflective of drug interaction. In view of the wide interindividual variation in level of phenytoin and the unpredictability of interaction with other anticonvulsants, the monitoring of drug levels become mandatory.

Monitoring of phenobarbitone in epileptic children.

Seventy-five children with different nutritional status, who were receiving phenobarbitone for treatment of various seizure disorders, were monitored for their plasma steady state level, therapeutic efficacy and toxicity. A wide inter individual variation in the steady state level was observed. About 10 percent of them had subtherapeutic level, while nearly 30 percent of them had potentially toxic levels, the remaining were within therapeutic range of 10-25 micrograms/ml. Poor compliance was found to be an important contributing factor for the variations in the level. Steady state levels were significantly higher in children with grade II protein energy malnutrition (PEM) than normally nourished children. A good correlation existed between plasma drug level and therapeutic response in nearly 60 percent of the children. Clinical toxicity was observed in nearly two thirds of the children, sedation and behavioral problems being the most common. The importance of monitoring the drug level is discussed for the proper management of epileptic children.

Antiviral efficacy of homoeopathic drugs against animal viruses

The antiviral effect of homoeopathic drugs against two animal viruses, Chicken Embryo Virus (CEV) of fowls and Simliki Forest Virus (SFV), causing encephalitis and death in mice were investigated. In all 10 drugs in 33 potencies were tested against CEV and 8 drugs in 26 potencies showed varying degree of virus inhibition. The drugs that caused 100//inhibition of CEV were Typhoidinum 200, Hydrophobinum 1000, Tuberculinum 1000, Nux vomica 200, and Malandrinum 1000. Of the drugs tested in 11 potencies against SFV, none were found effective in either preventing disease or death of mice infected with this virus

Immunoregulatory role of stress mediators in rheumatoid arthritis.

Eighteen patients suffering from chronic rheumatoid arthritis were selected for the present study. Plasma levels of stress hormones like catecholamines and cortisol were found to be elevated. At the same time reduction in percentage of E-rosette forming lymphocytes and an elevation in levels of major serum immunoglobulins (IgG, IgA and IgM) were observed. Certain other alterations in serum protein fractions were also noted. Probable role of these factors in the pathogenesis of this disease is discussed and attempts have been made to inter relate these findings.