Two-stage SBR for treatment of oil refinery wastewater

A two-stage sequencing batch reactor (SBR) system was used for treatment of oily wastewater with COD and oil and grease (O&G) concentrations ranging from 1,722-7,826 mg/L and 5,365-13,350 mg/L, respectively. A suitable start-up protocol was developed using gradual increase in oily wastewater composition with methanol as the co-substrate. This strategy enabled a short acclimation period of 12 days for the sludge in the two-stage SBR to adapt to the oily wastewater. After acclimation, the 1st stage and 2nd stage SBRs were able to achieve COD removals of 47.0+/-2.4% and 95.3+/-0.5%, respectively. The 1st stage SBR was able to achieve 99.8+/-0.1% of O&G removal and effluent O&G from the 1st stage SBR was only 6+/-2 mg/L. The 2nd stage SBR was used to further remove COD in the effluent from the 1st stage SBR. The final effluent from the 2nd stage SBR had a COD concentration of 97+/-16 mg/L with no detectable O&G content. Thus, a two-stage SBR system was shown to be feasible for treating high strength oily wastewater to meet the local discharge standards.

Relationships of perceived benefits and barriers to physical activity, physical activity participation and physical fitness in Hong Kong female adolescents

AIM

Previous studies that examined participation in physical activity suggested that female adolescents were less active compared with males. However, the relationship between physical fitness, physical activity participation, and perceived benefits and barriers for physical activity to adolescents, irrespective of gender, has not been made clear. This study examines the association of these factors in female adolescents.

METHODS

Physical activity participation and perceived benefits and barriers to physical activity were determined in 206 secondary school female subjects (aged 11 to 18) using a validated questionnaire.

RESULTS

Subjects with a correct concept about optimal physical activity participation to maintain health engaged in an activity level higher than the group without a correct concept (t=2.37, p=0.02). A significant correlation was established between the physical activity participation with "health" (r=0.22, p<0.001) and "body image" (r=0.17, p=0.02) in the perceived benefit category. The individual factor, "make me feel better in general" in the "health" category (p=0.04) and the intention to participate (p<0.001) were shown to be significant predictors for physical activity participation. The combined effects of the regression model explained 35.9% of the variance in participation in physical activity.

CONCLUSION

Policies to support regular physical activity participation at school and out-of-school should be strategically developed and promoted, highlighting the promotion of health benefits in exercise and the reinforcement of initial intent towards exercise.

Meningioma--the Sarawak General Hospital experience

The aim of this study was to determine the factors for the large size of intracranial meningiomas at the time of presentation to the Sarawak General Hospital. The data was collected prospectively from 1/3/2000 to 28/2/2001. During this period a total of 57 cases of intracranial tumours were operated upon. Twenty of these cases (35%) were meningioma, making meningioma the most common intracranial tumour operated in the Neurosurgery service here with one to two cases operated per month. Headache was the most common symptom. The average duration of symptoms before the diagnosis was made was twenty-five months, the longest being fifteen years. The patients needed an average of seven visits prior to the diagnosis.

Suggestive evidence for linkage of schizophrenia to markers at chromosome 15q13-14 in Taiwanese families

In order to evaluate the linkage of schizophrenia to loci at chromosome 15q, we genotyped six microsatellite markers at chromosome 15q11-14 in 52 Taiwanese schizophrenic families. Two phenotype models (narrow: DSM-IV schizophrenia only; and broad: including schizophrenia, schizoaffective, and other nonaffective psychotic disorders) were used to define the disease phenotype. Maximum nonparametric linkage scores (NPL scores) of 3.33 (P = 0.0003) and 2.96 (P = 0.0008) were obtained at the marker D15S976 under broad and narrow models, respectively. Positive linkage results were also observed at the marker D15S1360, previously reported to have significant linkage to a neurophysiological deficit of schizophrenia, with NPL scores of 2.71 (P = 0.003) and 2.78 (P = 0.002) under broad and narrow models, respectively. The results provide suggestive linkage evidence of schizophrenia to loci at chromosome 15q13-14 in an ethnically distinct Taiwanese sample.

Assessing the risk of sudden cardiac death

Detection of a major risk factor for sudden death in an otherwise asymptomatic person often raises major difficulties in management, particularly where the only treatment available is invasive, such as the implantable defibrillator. Recent guidelines have described the appropriate use of this technology, but often difficulty remains. This is particularly the case where the condition is newly recognised and its natural history not yet extensively described. A 63 year old man, whose condition was diagnosed as Brugada syndrome, in whom this problem is illustrated is described.

Cerebral blood flow in obsessive-compulsive patients with major depression: effect of treatment with sertraline or desipramine on treatment responders and non-responders

We examined the effects of sertraline and of desipramine on patients with OCD and comorbid major depressive episodes at study entry. Sixteen patients, 9 receiving sertraline and 7 desipramine, received HMPAO SPECT scans while free of medication and after 12 weeks of treatment. Patients on sertraline showed significantly reduced regional cerebral blood flow (rCBF) in the right prefrontal and temporal regions. Patients on desipramine showed more diffuse rCBF reductions in frontal and temporal regions, more so in the left side. In a second analysis, patients who had a symptom reduction on the Yale-Brown Obsessive Compulsive Scale (YBOCS), irrespective of the type of medication, were retrospectively classified as 'responders' to treatment. Eleven patients were 'responders' and 5 'non-responders'. Before being medicated, responders differed from non-responders through higher rCBF in prefrontal regions, mostly on the left, and higher rCBF in the cingulate and basal ganglia bilaterally. After 12 weeks of treatment, responders showed a diffuse reduction of rCBF in prefrontal regions while non-responders showed only a few scattered low-frequency responses. Thus, higher prefrontal and subcortical activity was associated with better response to drug treatment. In addition, clinical change, but not the administration of medication as such, was associated with a decrease of prefrontal rCBF.

Hypertensive basal ganglia hemorrhage: a prospective study comparing surgical and nonsurgical management

BACKGROUND

The optimal treatment of hypertensive supratentorial intracerebral hemorrhage is still debated. Some studies have shown no improvement in survival or functional outcome after surgery when compared to conservative management while others have shown otherwise.

METHODS

This study was a prospective trial, matching patients for hematoma volume and Glasgow Coma score on admission.

RESULTS

There were a total of 34 patients. Seventeen were treated conservatively and 17 surgically. There was no significant difference between the two groups in terms of age, GCS, hematoma volume, or presence of intraventricular blood. At 3, 6, and 12-month follow-up, they were assessed using the Modified Barthel Index by a blinded observer. There was no difference between the two groups at 3, 6, or 12 months follow-up. The mortality rate was similar in the two groups.

CONCLUSIONS

Based on this study and review of the literature, we cannot recommend routine evacuation of clots to treat these hemorrhages.

Therapeutic drug monitoring for immunosuppressants

BACKGROUND

Immunosuppressants have significantly increased patient survival, e.g. in renal transplant up to 90% for the first year.

METHODS

Four immunosuppressants are used for clinical applications in the United States: cyclosporine (CsA) (Sandimmune and Neoral), FK 506-tacrolimus (ProGraf), mycophenolic mofetil (CellCept)--the prodrug for the mycophenolic acid (MPA), and rapamycin (RAPA) (Sirolimus). For CsA and FK 506, the rationale for monitoring is due to the variable pharmacokinetics, acute infection, dosage adjustment, non-compliance check, and for long-term maintenance therapy. Targeted whole blood concentrations ranges are: for CsA, 100-400 ng/ml depending on the methods, therapy and organs; and for FK 506, 5-20 ng/ml. For MPA, drug bioavailability--the plasma area-under-curve up to 12 h of 32.2-60.6 mg h/l was correlated to the biopsy-proven rejection rate of <10%. Monitoring is advocated for liver and renal transplants, for pediatrics, and for checking for non-compliance. RAPA monitoring is useful to check for variable pharmacokinetics, for non-compliance and others. The therapeutic range is tentatively targeted for 5-15 ng/ml. Monitoring methodologies are: for CsA, immunoassays such as fluorescence polarization immunoassay, and liquid chromatography (LC); for FK 506, microparticle enzyme immunoassay (MEIA); for MPA, enzyme multiplied immunoassay and LC; and for RAPA, MEIA, LC and LC-mass spectrometry. Proficiency survey programs for CsA and FK 506 are available from the US and Europe.

CONCLUSIONS

Monitoring of immunosuppressants has become an essential adjunct to the drug therapy for organ transplant patients.

SNX3 regulates endosomal function through its PX-domain-mediated interaction with PtdIns(3)P

The sorting nexin (SNX) protein family is implicated in regulating membrane traffic, but the mechanism is still unknown. We show that SNX3 is associated with the early endosome through a novel motif (PX domain) capable of interaction with phosphatidylinositol-3-phosphate (PtdIns(3)P). Overexpression of SNX3 alters endosomal morphology and delays transport to the lysosome. Transport from the early to the recycling endosome is affected upon microinjection of SNX3 antibodies. Our results highlight a novel mechanism by which SNX proteins regulate traffic and uncover a novel class of effectors for PtdIns(3)P.

Genotyping of cytochrome P450 2D6*3 and *4 mutations using conventional PCR

Cytochrome P450 (CYP450) mixed-function mono-oxygenases, consisting of more than 30 enzymes, are responsible for the metabolism of a large number of drugs and metabolites. With the rapid advances in the human genome project, the role of genetic polymorphism in drug metabolism may become an important adjunct for rational drug therapy, and for the explanation of drug toxicity and interactions. This preliminary study modified a previously described procedure for genotyping CYP2D6*3 and *4. An additional step included uracil-DNA glycosylase for the prevention of "carry-over" contamination. DNA was extracted from peripheral blood using PureGene DNA Isolation kit. CYP2D6*3 and *4 sequences were amplified by PCR, followed by digestion with restriction endonuclease Msp1 and Mva1, respectively. Resulting fragments were analyzed by electrophoresis and visualized by ethidium bromide staining. Poor metabolizers of *3 mutation showed 168-, 82- and 20-bp bands, while those of *4 showed a single 355-bp band. Using these protocols, 22 individuals were genotyped, showing the following prevalence for *3 and *4: 0 and 3, respectively-comparable to those of the general population. This method provides a reliable means of genotyping CYP2D6*3 and *4.

Effects of ingesting a large volume of carbohydrate-electrolyte solution on rehydration during recovery and subsequent exercise capacity

This randomized, double-blind study examined the effects of rehydration per se and rehydration plus carbohydrate (CHO) ingestion during recovery (REC) on subsequent endurance running capacity. Nine men ran at 70% VáO2max on a level treadmill for 90 min (T1) on two occasions, followed by a 4 hour REC and a further exhaustive run at the same speed (T2). During the first 3 hours of REC, subjects drank either a 6.9% CHO-electrolyte solution (CE) or a CHO- and electrolyte-free sweetened placebo (PL) every 30 min. Volumes prescribed were 200% of the fluid lost after T1, but the actual volume of fluid ingested during the REC ranged from 113-200% and 88. 5-200% of the body mass lost for the CE and PL trials (NS). However, positive fluid balance was found in both trials after REC. During T2, run time was 24.3 +/- 4.4 min longer in the CE trial (69.3 +/- 5.5 vs. 45.0 +/- 4.2 min; p <.05). Higher blood glucose concentrations were observed throughout REC in the CE trial. These results suggest that ingesting a CHO-electrolyte solution is more effective in restoring endurance capacity compared to the same large volume of placebo, even though complete rehydration was achieved in both trials.

New fluorescence polarization immunoassays for analysis of barbiturates and benzodiazepines in serum and urine: performance characteristics

The performance of the new fluorescence polarization immunoassay reagents Cassette COBAS INTEGRA Serum Benzodiazepines assay (SBENZ) and Cassette Serum Barbiturates assay (SBARB) was evaluated as compared to other immunoassays (Abbott TDx Serum Benzodiazepines, Abbott TDx Urine Benzodiazepines, Behring EMIT Serum Benzodiazepines, Abbott ADx Serum Barbiturates, Behring EMIT Serum Barbiturates, and the COBAS INTEGRA Barbiturates (BARB) urine assay) and gas chromatography-mass spectrometry (GC-MS). Recoveries of nordiazepam and secobarbital using the SBENZ and SBARB assays, respectively, were equivalent for serum, plasma, and urine. Cross-reactivities of structurally related benzodiazepines, barbiturates, and their metabolites were very similar in serum and urine for the SBENZ and SBARB assays. Precision was within 5.4% for SBENZ serum and within 11% from 10 to 100 ng/mL for urine. Precision was within 5% for SBARB serum and within 7% from 136 to 277 ng/mL for the urine application. The standard curves for SBENZ and SBARB were stable for at least 16 weeks with the reagents stored open on the COBAS INTEGRA analyzer. Clinical comparison of the SBENZ serum assay indicated an increased pickup rate, as confirmed by GC-MS, compared to TDx and EMIT. The diagnostic sensitivities of the SBENZ serum application, TDx, and EMIT versus GC-MS were 100%, 89%, and 36%, respectively. The diagnostic specificities were 71%, 79%, and 100%, respectively. The diagnostic sensitivities of the SBENZ urine application and TDx versus GC-MS were 100% and the diagnostic specificities were 88%. The increased positive pick-up of the SBENZ assay compared to the other immunoassays is most probably due to the difference in the limit of detection (LOD) and the increased cross-reactivity for the low-dose benzodiazepines. Clinical comparison of the SBARB serum assay indicated an increased positive pick-up rate, as confirmed by GC-MS. The diagnostic sensitivities of the SBARB serum application, ADx, and EMIT versus GC-MS were 96%, 65%, and 35%, respectively. The diagnostic specificities were all 100%. The diagnostic sensitivities for the SBARB urine application and BARB versus GC-MS were all 100%, and the diagnostic specificities were all 91%. The SBENZ and SBARB kits demonstrated increased sensitivity for the detection of benzodiazepines and barbiturates in both serum and urine compared to the other immunoassays.

Chiral high-performance liquid chromatographic analysis of fluoxetine and norfluoxetine in rabbit plasma, urine, and vitreous humor using an acetylated beta-cyclodextrin column

Fluoxetine (Prozac) is a potent selective serotonin reuptake inhibitor used for the treatment of major depression. Both fluoxetine (F) and its demethylated metabolite, norfluoxetine (NF), are racemic. S-Fluoxetine (SF) and S-norfluoxetine (SNF) are more potent inhibitors of serotonin reuptake than R-fluoxetine (RF) and R-norfluoxetine (RNF). Quantitation of individual enantiomers may provide a greater understanding of pharmacokinetic properties. The objective of this study was to perform a limited chiral selectivity study using rabbit plasma, urine, and vitreous humor analyzed by a solid-phase extraction protocol and a newly developed chiral analysis with an acetylated beta-cyclodextrin (CD) column. Liquid chromatographic parameters for CD were as follows: a mobile phase composition of methanol/0.3% triethylamine buffer, pH 5.6, (30:70), a flow rate of 1 mL/min, detection at 214 nm, and a temperature of 40 degrees C. Elution order was SNF, SF, RNF, and RF with capacity factors of 6, 7, 8, and 9, respectively. The corresponding resolution factors were as follows: R1,2 = 0.8, R2,3 = 1.2, and R3,4 = 0.9. The conditions for solid-phase extraction were optimized for Varian Bond Elut Certify columns. Following sample application, the column was rinsed with water, acetic acid, and then with methanol. Drug enantiomers were eluted with methylene chloride, isopropanol, and ammonium hydroxide (78:20:2). After extract evaporation, the extract residue was reconstituted for high-performance liquid chromatographic analysis. To investigate chiral pharmacology, a biodistribution study was performed by administering 2 mg/kg of F to five rabbits. Blood, urine, and vitreous specimens were collected. Plasma samples collected 45 min postinjection showed nearly equal concentrations of RF and SE After 24 h, the only metabolite detected in plasma was RNF. Drugs were not detectable in vitreous humor. Urine concentrations of SNF, SF, RNF, and RF were 51, 76, 34, and 8 microg/L, respectively. The CD column along with the described extraction protocol may be used for a chiral selectivity study of fluoxetine.

Endoglin expression on human microvascular endothelial cells association with betaglycan and formation of higher order complexes with TGF-beta signalling receptors

Transforming growth factor-beta (TGF-beta) plays an important role in angiogenesis and vascular function. Endoglin, a transmembrane TGF-beta binding protein, is highly expressed on vascular endothelial cells and is the target gene for the hereditary haemorrhagic telangiectasia type I (HHT1), a dominantly inherited vascular disorder. The specific function of endoglin responsible for HHT1 is believed to involve alterations in TGF-beta responses. The initial interactions on the cell surface between endoglin and TGF-beta receptors may be an important mechanism by which endoglin modulates TGF-beta signalling, and thereby responses. Here it is shown that on human microvascular endothelial cells, endoglin is co-expressed and is associated with betaglycan, a TGF-beta accessory receptor with which endoglin shares limited amino acid homology. This complex formation may occur in either a ligand-dependent or a ligand-independent manner. In addition, the occurrence of three higher order complexes containing endoglin, type II and/or type I TGF-beta receptors, on these cells is demonstrated. Our findings suggest that endoglin may modify TGF-beta signalling by interacting with both betaglycan and the TGF-beta signalling receptors at physiological receptor concentrations and ratios.

Influence of different amounts of carbohydrate on endurance running capacity following short term recovery

This study examined the effect of ingesting different amounts of carbohydrate (CHO) during 4 h recovery (REC) from prolonged running, on subsequent endurance running capacity when subjects were fully rehydrated. Nine men ran at 70% VO2max on a treadmill for 90 min (T1), followed by the REC and a run to exhaustion at the same speed (T2) on two occasions. Thirty minutes into REC, subjects ingested 50 g of CHO from a 6.5% CHO-electrolyte solution (CE) on both occasions. Thereafter, subjects ingested either the same CE or a placebo (PL) every 30 min for the first 3 h of REC. The total volume ingested was equal to 150% of the body mass lost during T1 which achieved rehydration during REC in both trials. Higher blood glucose and serum insulin concentrations (P<0.05) were observed during REC in the CE trial. Nevertheless, similar run times were achieved during T2 in both trials (CE: 56.9+/-8.1 min and PL: 65.4+/-7.8 min) (+/- S.E.M) (NS). Therefore, these results suggest that ingestion of 50 g of CHO immediately after prolonged exercise, and rehydration with a placebo solution, results in a similar endurance capacity, after a 4 h recovery, as ingesting 3 times more CHO (approximately 167 g CHO) over the same period.

Age-dependent core temperature responses of conscious rabbits to acute hypoxemia

Experiments were carried out on chronically instrumented newborn and older rabbits to characterize their core temperature (T(c)) responses to acute hypoxemia and to differentiate "forced" vs. "regulated" thermoregulatory responses. Three age ranges of kits were studied: 4-6, 9-11, and 28-30 days of age. During an experiment, T(c), selected ambient temperature (T(a)), and oxygen consumption were measured from kits studied in a thermocline during a control period of normoxemia, an experimental period of normoxemia or hypoxemia (fraction of inspired oxygen 0.10), and a recovery period of normoxemia. We reasoned that no change or a decrease in T(a) while T(c) decreased during hypoxemia would indicate a regulated thermoregulatory response, whereas an increase in T(a) while T(c) decreased during hypoxemia would indicate a forced thermoregulatory response. T(c) decreased during acute hypoxemia in the older kits but not in the 4- to 6-day-old kits; the decrease in T(c) was accentuated on postnatal days 28-30 compared with postnatal days 9-11. T(a) decreased or stayed the same during exposure to acute hypoxemia. Our data provide evidence that postnatal maturation influences the T(c) response of rabbits to acute hypoxemia and that the decrease in T(c) during hypoxemia in the older kits results from a regulated thermoregulatory response.

Challenges of toxicology for the millennium

In meeting the challenges of toxicology, clinical and forensic toxicologists should expand their services and engage in research and development to meet changing needs. Expanding roles could potentially derive from the threat of terrorism, genotyping for interpretation of potential toxic drug interactions, and criminalistic testings. At the threshold of the next millennium, terrorism via weapons of mass destruction (WMD) has migrated from the war zones to civilian settings. These WMD may be in the form of nuclear, biological, and chemical devices (NBC). Recently, the possible use of chemical/biological weapons in the Middle East conflicts, the use of sarin in a Tokyo subway station, and the unregulated availability of nuclear fuel in some countries all have heightened the potential for international and domestic NBC. In preparation for NBC, both government and civilians in major American cities have been trained for safe handling of patients and casualties. Forensic and clinical toxicologists should be knowledgeable about the clinical pharmacology, safe samples processing, and possible screening and/or analysis of samples exposed to or containing: vesicants; cyanide; and nerve, riot control, and pulmonary agents. These samples may be transported for further analysis and confirmed by designated central laboratories. In criminal/correctional settings, toxicologists should engage in quality assurance and consultation with attorneys, judges, and correctional professionals. With the emergence of pharmacogenetics, genotyping may enhance rational drug therapy for enhanced patient care, and may explain adverse or fatal drug reactions in postmortem analysis.

Clinical efficacy of the Abbott Tacrolimus II assay for the IMx

Monitoring tacrolimus is essential to maintain therapeutic concentrations. Performance of the new Abbott Tacrolimus assay (FK II) was evaluated and compared to the original tacrolimus assay (FK I). 189 trough whole blood samples from transplant cases were included in the study. Samples (n = 117) with FK I concentrations > 5 ng/mL were reanalyzed with the FK II assay. Patient samples (n = 43) that had FK I concentration < 5 ng/mL with apparent mean and range of 3.1 ng/mL and 0.7 to 4.5 ng/mL, respectively, were also reanalyzed with FK II to yield a mean of 5.9 ng/mL with a range of 2.9 to 10.8 ng/mL. Checking for patient compliance, samples (n = 10) with a FK I concentration of 0 ng/mL were re-analyzed. With one exception of a mislabeled cyclosporine sample, all samples (n = 9) showed FK506 levels greater than 2 ng/mL with the FK II assay. The FK II assay was shown to be a clinically efficacious assay, with improved sensitivity and acceptable precision versus the previous FK I assay.

Acute zolpidem overdose--report of two cases

This report describes two cases of acute zolpidem overdose. The decedent in the first case was a 36-year-old female found dead in bed in her secured home. She had a history of psychiatric illness, including paranoid disorder, depression with panic episodes, and post-traumatic stress disorder. She was treated with risperidone and sertraline. Nine months prior to her death, the decedent was also prescribed zolpidem (Ambien). The postmortem examination revealed white foam within the larynx and upper trachea, which is indicative of pulmonary edema. Toxicological analyses of the urine showed the presence of caffeine, risperidone, and zolpidem. Subsequent quantitation of postmortem iliac serum revealed 5.6 microg/L of 9-hydroxyrisperidone and the following zolpidem concentrations: blood (subclavian), 4.5 mg/L; blood (iliac), 7.7 mg/L; vitreous humor, 1.6 mg/L; bile, 8.9 mg/L; urine, 1.2 mg/L; liver, 22.6 mg/kg; and gastric contents, 42 mg. The second case involved a 58-year old female, also found dead in bed, with white foam around her mouth. The decedent had a 25-year history of hypertension and mental illness--manic depression and schizophrenia. She was medicated with carbamazepine, naproxen, risperidone, and zolpidem. The postmortem examination revealed cardiomegaly, pulmonary edema, hepatomegaly, mild coronary atherosclerosis, and no signs of trauma. Toxicological analyses of the urine showed the presence of zolpidem and carbamazepine and metabolite. Zolpidem concentrations were as follows: blood (iliac), 1.6 mg/L; vitreous humor, 0.52 mg/L; bile, 2.6 mg/L; liver, 12 mg/kg; and gastric contents, 0.9 mg. The zolpidem blood concentrations of these cases are consistent with those of the previously published fatalities. The blood/vitreous humor ratios of zolpidem were 2.81 (subclavian) and 4.81 (iliac) in the first case and 3.08 (iliac) in the second case. These ratios, along with the sampling times of blood and vitreous humor for both cases, are not conclusive to indicate a definitive presence or absence of postmortem drug redistribution of zolpidem. The cause of death for both cases was determined to be acute zolpidem overdose, and manner of death was suicide.

Comparison of the serum barbiturate fluorescence polarization immunoassay by the COBAS INTEGRA to a GC/MS method

The authors evaluated a new Cassette Serum Barbiturates fluorescence polarization immunoassay (FPIA) on the COBAS INTEGRA. The assay was calibrated with secobarbital standards at 0, 0.5, and 4.0 microg/mL. The assay range was 0.030 to 80 microg/mL using an automatic 1/20 postdilution feature. Precision was established for two COBAS INTEGRA instruments for ten days by assaying secobarbital target concentrations ranging from 0.125 to 2.2 microg/mL. The coefficients of variation (CV) for the above target concentrations for the first instrument ranged from 2.7% to 8.3%, and for a second instrument, 3.8 to 8.3%. Seven clinically elevated bilirubin samples were spiked with 0.46 and 1.77 microg/mL secobarbital. Bilirubin interference was less than 10.9 and less than 7.9%, respectively. The average recovery ranged from 85% to 94%. The mean difference in recovery in serum versus plasma was < or = 3%. Fifty-two clinical samples were analyzed for butalbital, pentobarbital, secobarbital, and phenobarbital by GC/MS, and the results were compared to the new Cassette Serum Barbiturates FPIA. The diagnostic sensitivity and specificity were 95% and 100%, respectively. Both FPIA and GC/MS assays are clinically efficacious for monitoring serum barbiturates.

Spontaneous subarachnoid haemorrhage and outcome--results from Tan Tock Seng Hospital, Singapore

AIM OF STUDY

To ascertain the number of cases of spontaneous (aneurysmal) subarachnoid haemorrhage presenting to Tan Tock Seng Hospital, Singapore, over a one year period, the demographics of the patients involved, their treatment and their eventual outcome.

METHOD

A retrospective study from June 1995 to June 1996.

RESULTS

There were 62 patients admitted over this period with an average of 5 patients per month. Their ages ranged from 9 to 85 years with a mean of 54 years. All 62 patients underwent 4-vessel cerebral angiograms. Forty-three patients (69%) underwent clipping of their aneurysms. Twelve patients (19%) had negative angiograms. Four patients (6%) underwent coiling of their aneurysms via interventional neuroradiology techniques. Patients with subarachnoid haemorrhage of Grades 1 to 3 on the WFNS (World Federation of Neurological Surgeons) grading had a favourable outcome (Glasgow Outcome Score of 4 and 5) in 85% of the cases. The overall mortality rate for the operated group (all grades) was 11%. However for the group with good WFNS grading, namely the Grade 1 to 2 groups, there were no deaths. Twenty-four percent of patients developed clinically symptomatic vasospasm. Eighteen percent of patients required ventriculo-peritoneal shunting for hydrocephalus secondary to the subarachnoid haemorrhage. The overall management mortality (operated and non-operated cases) was 14% for proven aneurysmal and angiographically-negative spontaneous subarachnoid haemorrhage. These results are comparable to that of other reputable centers reported in the literature.