Cloning and expression of Staphylococcus simulans lysostaphin enzyme gene in Bacillus subtilis WB600

Lysostaphin is a glycylglycine endopeptidase, secreted by Staphylococcus simulans, capable of specifically hydrolyzing pentaglycine crosslinks present in the peptidoglycan of the Staphylococcus aureus cell wall. In this paper, we describe the cloning and expression of the lysostaphin enzyme gene in Bacillus subtilis WB600 host using pWB980 expression system. Plasmid pACK1 of S. simulans was extracted using the alkaline lysis method. Lysostaphin gene was isolated by PCR and cloned into pTZ57R/T-Vector, then transformed into Escherichia coli DH5α. The amplified gene fragment and uncloned pWB980 vector were digested using PstI and XbaІ enzymes and purified. The restricted gene fragment was ligated into the pWB980 expression vector by the standard protocols, then the recombinant plasmid was transformed into B. subtilis WB600 using electroporation method. The recombinant protein was evaluated by the SDS-PAGE method and confirmed by western immunoblot. Analysis of the target protein showed a band corresponding to 27-kDa r-lysostaphin. Protein content was estimated 91 mg/L by Bradford assay. The recombinant lysostaphin represented 90% of its maximum activity at 40 °C and displayed good thermostability by keeping about 80% of its maximum activity at 45 °C. Heat residual activity assay of recombinant lysostaphin demonstrated that the enzyme stability was up to 40 °C and showed good stability at 40 °C for 16 h incubation.

Genotype characterization of occult hepatitis B virus strains among Egyptian chronic hepatitis C patients

Chronic hepatitis C virus (HCV) infection combined with occult hepatitis B virus (HBV) infection has been associated with increased risk of hepatitis, cirrhosis and hepatocellular carcinoma. This study aimed to determine the prevalence of occult HBV infection among Egyptian chronic HCV patients, the genotype and occurrence of surface gene mutations of HBV and the impact of co-infection on early response to treatment. The study enrolled 162 chronic HCV patients from Ismailia Fever Hospital, Egypt, who were HBV surface antigen-negative. All patients were given clinical assessment and biochemical, histological and virological examinations. HBV-DNA was detectable in sera from 3 patients out of the 40 patients who were positive for hepatitis B core antibody. These 3 patients were responsive to combination therapy at treatment week 12; only 1 of them had discontinued therapy by week 24. HBV genotype D was the only detectable genotype in those patients, with absence of "a" determinant mutations among those isolates.

Subfertility treatment in women with systemic lupus erythematosus

This study comprised of 65 infertile patients with systemic lupus erythematosus (SLE). The aim was to study causes and different modalities used for the management of subfertile patients with SLE. All patients were diagnosed to have SLE according to the standard criteria of diagnosis. All patients were scheduled to expectant treatment, ovulation induction and timed intercourse, intrauterine insemination (IUI), intracytoplasmic sperm injection (ICSI). Anovulation was in 20 patients (20%), due to PCOS in 10 cases and due to other causes in three patients. A total of 28 patients (43.1%) needed laparoscopy for their work-up of infertility. Male factor for infertility was present in nine couples (16.7%). Ovulation induction and timed intercourse was adopted for a maximum 6 cycles and IUI for 3 cycles. In vitro fertilisation (IVF)/ICSI was needed in five cases using standard long agonist protocol. Four cases were complicated by significant ovarian hyperstimulation syndrome after conventional ovarian stimulation and cycles were cancelled. Pregnancy occurred in 20 women. Ovarian stimulation for ovulation induction and IVF seems to be safe and successful in well selected women with non-complicated SLE.

The epidemiology of schistosomiasis in Egypt: Ismailia governorate

A multi-stage stratified sample of 12,515 individuals from 1,941 households in 42 villages in the Ismailia governorate of Egypt were surveyed for schistosomal infection. A subset of 2,390 subjects were surveyed for morbidity by physical and ultrasonographic examination. The prevalence of Schistosoma mansoni infection in rural Ismailia was 42.9% and the geometric mean egg count (GMEC) was 93.3 eggs/gram of stool, with considerable variability between communities. Prevalence and intensity peaked in the 20-30-year-old age group and was higher in males than in females. Prevalence and intensity of S. haematobium was very low: 1.8% and 3.5 ova/10 ml of urine GMEC, respectively. Canal water exposure risk factors for S. mansoni infection were males bathing (odds ratio [OR] = 2.2), females washing clothes (OR = 1.9), and children playing or swimming (OR = 2.3). Presence of in-house piped water supply and latrine lowered infection rates (P < 0.001 and P = 0.002, respectively). Histories of S. mansoni infection (OR = 1.6) or treatment (OR = 1.5) and blood in feces (OR = 3.5) were associated with infection. Hepatomegaly (16.0%) was more frequently detected than splenomegaly (3.6%) by physical examination, with both being more frequent in older age groups. Splenomegaly, but not hepatomegaly, was associated with presence of S. mansoni ova in stools (OR = 1.4) and the community burden of infection (P = 0.02). Ultrasonographically detected hepatomegaly, splenomegaly, and periportal fibrosis (PPF) were detected in 43.0%, 17.4%, and 39.7% of the subjects, respectively. The higher grades of PPF were rare. Ultrasonographically detected splenomegaly, not hepatomegaly, was associated with S. mansoni infection, community burden of infection, and PPF. Risk factors for PPF were the same as for S. mansoni infection. There was a marginal association of PPF with infection and none (P = 0.33) with the intensity of infection in individuals or in the community. We conclude that in rural Ismailia, S. haematobium infection is rare but the prevalence and intensity of infection with S. mansoni is high. The risk of infection is associated with environmentally detected factors and behaviors. Hepatosplenic morbidity attributable to S. mansoni infection is low, presumably because of the favorable effect of wide application of praziquantel therapy.

The use and limitations of ultrasonography in the diagnosis of liver morbidity attributable to Schistosoma mansoni infection in community-based surveys

The objective of this population-based study was to estimate the liver morbidity attributable to Schistosoma mansoni infection by ultrasonography adopting the proposed standard protocols of the Cairo Meeting on Ultrasonography, 1991. We examined 2384 individuals representing 20% of the households of the rural population of the Ismailia Governorate, East of Delta, Egypt. Prevalence of S. mansoni and S. haematobium infections were 40.3% and 1.7% respectively. Portal tract thickening (PTT) grade 1, 2 and 3 considered diagnostic of schistosomal liver morbidity was detected in 35.1%, 1.3 and 0.2 individuals respectively. Generally, ultrasonographically-detected pathological changes increased with age, but correlated with intensity of infection only in age group 20-59 years. Comparing individuals with and without S. mansoni infections in an endemic and a non-endemic community indicated no significant difference between the former and the latter in either case.

IN CONCLUSION

ultrasonography had a limited value in estimating schistosomal liver morbidity in our population-based study where early grades of liver morbidly were prevalent. The criteria of diagnosing grade I portal fibrosis need to be revised as well as the staging system proposed by the Cairo Meeting on ultrasonography in schistosomiasis.

The clinical significance of lithium-nonsteroidal anti-inflammatory drug interactions

There is conclusive evidence that nonsteroidal anti-inflammatory drugs can increase serum lithium levels, diminish renal lithium clearance, and possibly induce lithium toxicity. Such an interaction has occurred in patients with normal renal function. The effect on serum lithium levels varies greatly among different nonsteroidal anti-inflammatory drugs, indomethacin seeming most potent. On the other hand, there is no convincing evidence that sulindac and aspirin affect serum lithium levels to a clinically significant degree. Ibuprofen and naproxen can significantly increase serum lithium levels, but there is marked interindividual variation. Patients receiving nonsteroidal anti-inflammatory drugs must have their serum lithium levels checked every 4-5 days until the extent of drug interaction is assessed. A reduction in lithium dosage may be needed in some cases.

Ibuprofen can increase serum lithium level in lithium-treated patients

The interaction between lithium and ibuprofen was studied in nine male patients admitted to the geropsychiatric ward of a veterans administration medical center. The patients, diagnosed as having bipolar affective disorder or schizoaffective disorder, who had been kept on a steady-state lithium level, received lithium for 3 days, then lithium and ibuprofen (1800 mg/day) for 6 days, and then lithium for 5 days. Ibuprofen increased the serum lithium level and decreased the lithium clearance with marked interindividual variations. These findings indicate that lithium dosage may need to be reduced in some patients following initiation of ibuprofen therapy. There was no significant correlation between changes in lithium serum level and creatinine clearance. The possibility that a tubular renal prostaglandin system may affect lithium excretion needs further investigation.

Effects of cross-section structure on the dosimetric response functions for 0.4 to 10.0 MeV neutrons in the ICRU tissue sphere

The effect of the fluctuating cross-section structure in the energy range of 0.4 to 10.0 MeV on the dosimetric response functions of neutrons in the ICRU standard tissue sphere is analyzed. A Monte Carlo method with point-energy cross-section values, including coupled transport for neutrons and secondary charged particles, was used in the direct estimation of the absorbed dose and the dose equivalent. An approach was adopted in which source-energy band-average responses were calculated instead of the more usual approach involving monoenergetic source neutrons. Data were obtained for the newly defined term, ambient dose equivalent, at various depths, as well as the older index quantities. Such data generated were compared with information from other research workers. In general, good agreement was found, with due consideration to the differences engendered by the use of the source-energy band-average approach. Agreement was poorest for very shallow depths, corresponding to outer skin thickness, this being a most difficult depth to calculate accurately. The dosimetric data generated in this study should contribute to the ongoing efforts for the standardization of neutron protection dosimetry.

Lithium interaction with sulindac and naproxen

The interaction of lithium with sulindac and naproxen was studied in six sulindac-treated and seven naproxen-treated patients admitted to a geropsychiatry ward. Patients under a steady state lithium level received lithium for 3 days, then lithium + sulindac (300 mg/day) or naproxen (750 mg/day) for 6 days, and then lithium alone for 5 days. Sulindac failed to affect serum lithium levels and lithium clearance. The results with naproxen showed marked interindividual variations ranging from no increase to a 41.9% increase in serum lithium levels within 5 days. There was a corresponding decrease in lithium clearance in naproxen-treated patients. Patients undergoing lithium therapy might need a reduction of their lithium dosage following naproxen administration. More frequent serum lithium level determinations are required following initiation of naproxen therapy until the magnitude of the lithium-naproxen drug interaction can be adequately assessed in a given individual.

Drug abuse among state hospital psychiatric inpatients with particular reference to PCP

The pattern of alcohol and drug abuse among 78 consecutive newly admitted patients to a middle Tennessee state hospital psychiatric ward was examined. There was a high prevalence of alcohol, marijuana, hypnotic sedative, and stimulant abuse among this patient population within 1 month prior to their hospitalization. However, only 1 patient gave a history of PCP abuse and none of the 76 plasma samples analyzed by the GCN and GC2-N methods was positive for PCP or its common analogues. This study does not support a high prevalence of PCP abuse among this group of psychiatric patients.

Prostaglandins and schizophrenia: a review

1. Clinical observations and experimental findings are rendered which have raised the possibility that schizophrenia may be related to PGE deficiency and/or excess. 2. In favor of PGE1 deficiency are the findings that ADP-induced increase in synthesis and PGE1 stimulated cAMP accumulation are significantly lower in platelets of schizophrenic patients than in normal controls. 3. In favor of PGE excess are the findings that the concentration of immunoreactive PGE in cerebrospinal fluid of schizophrenics is higher than that of healthy controls, neurotic patients and patients undergoing neurological examination. 4. An argument against the PG excess hypothesis is that paracetamol, a substance which reduces PG levels has no therapeutic effect in schizophrenia. 5. The two hypotheses--PGE deficiency and PGE excess--are not compatible because of the bell shape dose response curve with PG's in certain biological systems.

Systematic studies with amoxapine, a new antidepressant

Amoxapine, a tricyclic dibenzoxazepine is an antidepressant which in the dosage range of 150-300 mg/day is notable for its rapid onset of action. Because of the rather long, approximately 30-hour, half-life of 8-hydroxyamoxapine, the active metabolite of amoxapine, the possibility was raised that amoxapine therapy may be carried out with single daily dosages. Such a dosage schedule may improve compliance and, if appropriately timed, decrease perception of some of the unwanted effects of the drug. To test the hypothesis that there may be no disadvantages and perhaps even advantages of a once-a-day regimen as compared to a divided dosage schedule, a 6-week double-blind clinical trial was carried out in 35 hospitalized patients with major (18 patients) and minor (17 patients) depressive disorders. While no statistically significant difference was found in overall therapeutic and adverse effects between the groups treated with single or divided daily doses, onset of therapeutic effect appeared a bit faster in the group treated with single daily doses. Of particular relevance for drugs which can be given in single daily doses is their effect on psychomotor performance tests. In view of the findings that a once-a-day dosage regimen with amoxapine may have advantages over divided daily doses, a second study was carried out in which the effects of amoxapine (50 and 100 mg) were compared to an inactive placebo and amitriptyline (50 mg) with and without ethanol in 8 normal male volunteers. The study was double-blind and followed a latin square design. Since the effects of amoxapine on motor reflex, visual-motor coordination and depth perception did not differ significantly from placebo, the results suggest that the effects of amoxapine on the performances measured are clinically insignificant. No significant interaction with ethanol was noted.

Amoxapine: once versus divided daily doses in neurotic and endogenous depression

In a six-week, double-blind clinical study of 35 hospitalized patients with the diagnoses of endogenous depression (18 patients) and depressive neuroses (17 patients), two dosage schedules of amoxapine were compared. While no statistically significant difference in overall therapeutic and adverse effects between the groups treated with single daily doses and divided daily doses were found by the end of the six weeks investigational period, onset of therapeutic effect was faster in the group treated with single daily doses. There was a significantly greater improvement in Anxiety-Somatization and Sleep Disturbance (HAM-D factors) in the group with depressive neurosis than in the group with endogenous depression.

Drug interactions in psychiatric practice

The interaction of neuroleptics, tricyclic antidepressants, monoamine oxidase inhibitors, lithium and anxiolytic sedatives with other drugs and food is reviewed with special emphasis on drug interactions commonly encountered in psychiatric practice. Clinical relevance and mechanism of action of such interactions are discussed. An update of the interaction of lithium with prostaglandin inhibitors is presented.

Interaction of indomethacin and ibuprofen with lithium in manic patients under a steady-state lithium level

The clinical effects of prostaglandin synthesis inhibitors were studied in lithium treated manic patients. While indomethacin increased plasma lithium concentration, the effect of ibuprofen was inconsistent. Adverse reactions included tremors unrelated to changes in plasma lithium levels; nausea and drowsiness in 1 ibuprofen treated patient possibly related to the slight increase in plasma lithium, and a syndrome consisting of running nose, malaise and generalized body aches in 1 indomethacin treated patient. Our findings are in support of an important interaction between prostaglandin synthesis inhibitors and especially indomethacin and lithium, which may result in an increase in adverse reactions.

Naltrexone in chronic schizophrenia. Results of a clinical trial

A 4-week clinical trial, including a 1-week placebo washout period, assessed the antipsychotic activity of naltrexone in 'newly admitted', actively hallucinating, chronic schizophrenics. Chronic naltrexone administration was found to benefit 2 patients and to be of no value in 3 patients. Responsive patients differed from non-responders by the presence of hallucinations despite adequate neuroleptic maintenance therapy and an appropriate response to pathological hallucinatory experience. On the basis of these findings, the possibility of a naltrexone-responsive schizophrenic subgroup was considered.

Indomethacin increases plasma lithium

The effects of indomethacin on plasma lithium concentrations and renal lithium clearance were investigated in three psychiatric patients and four normal volunteers. After steady-state plasma lithium concentrations had been reached, the subjects received indomethacin placebo for three to seven days, indomethacin (50 mg thrice daily) for seven days, and placebo again for three to seven days. Indomethacin increased plasma lithium concentrations by 59% in the psychiatric patients and 30% in the volunteers. Renal lithium clearance was reduced by indomethacin by 31% in the group as a whole, and prostaglandin synthesis, determined by measuring the major metabolite of PGE2 with mass spectrometry, was reduced by 55%. These results show that indomethacin reduces renal lithium clearance to an extent which may be clinically important. They also suggest that the renal clearance may be affected by a prostaglandin-dependent mechanism, possibly located in the distal tubule.