Comparison of Microtox and Xenoassay light as a near real time river monitoring assay for heavy metals.

Luminescence-based assays for toxicants such as Microtox, ToxAlert, and Biotox have been used extensively worldwide. However, the use of these assays in near real time conditions is limited due to nonoptimal assay temperature for the tropical climate. An isolate that exhibits a high luminescence activity in a broad range of temperatures was successfully isolated from the mackerel, Rastrelliger kanagurta. This isolate was tentatively identified as Photobacterium sp. strain MIE, based on partial 16S rDNA molecular phylogeny. Optimum conditions that support high bioluminescence activity occurred between 24 and 30°C, with pH 5.5 to 7.5, 10 to 20 g/L of sodium chloride, 30 to 50 g/L of tryptone, and 4 g/L of glycerol as the carbon source. Assessment of near real time capability of this bacterial system, Xenoassay light to monitor heavy metals from a contaminated river running through the Juru River Basin shows near real time capability with assaying time of less than 30 minutes per samples. Samples returned to the lab were tested with a standard Microtox assay using Vibrio fishceri. Similar results were obtained to Xenoassay light that show temporal variation of copper concentration. Thus, this strain is suitable for near real time river monitoring of toxicants especially in the tropics.

Final results of the global and Asia cohorts of KAMILLA, a phase IIIB safety trial of trastuzumab emtansine in patients with HER2-positive advanced breast cancer.

BACKGROUND: KAMILLA is a single-arm safety study of trastuzumab emtansine (T-DM1) in patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (BC; NCT01702571). We report the final analysis of cohort 2 (Asia) within the context of published cohort 1 (Global) findings. METHODS: Patients had HER2-positive, locally advanced, or metastatic BC progressing after chemotherapy and anti-HER2 therapy or ≤6 months after adjuvant therapy. The primary objective was to further evaluate T-DM1 (3.6 mg/kg, administered intravenously every 3 weeks) safety/tolerability, including the following adverse events of primary interest (AEPIs): grade ≥3 AEPIs (hepatic events, allergic reactions, thrombocytopenia, hemorrhage events), all grade ≥3 treatment-related AEs, and all-grade pneumonitis. RESULTS: KAMILLA enrolled 2185 patients (cohort 1, n = 2003; cohort 2, n = 182) as of 31 July 2019. Of these, 2002 and 181 per cohort were treated and included in the safety population. Approximately 70% of patients had two or more previous treatment lines in the metastatic setting. Median T-DM1 exposure was 5.6 and 5.0 months per cohort; median follow-up was 20.6 and 15.1 months. The overall AEPI rate was higher in cohort 2 (93/181; 51.4%) versus cohort 1 (462/2002; 23.1%), mostly driven by a higher grade ≥3 thrombocytopenia rate in cohort 2. In cohort 2, grade ≥3 thrombocytopenia was not associated with grade ≥3 hemorrhagic events and most (128/138) fully resolved. Grade ≥3 treatment-related AEPI rates were 18.4% (cohort 1) and 48.6% (cohort 2), the latter mainly due to thrombocytopenia. Any-grade pneumonitis rates were 1.0% and 2.2%. No new safety signals were identified. Median (95% confidence interval) progression-free survival was 6.8 months (5.8-7.6 months) and 5.7 months (5.5-7.0 months) in cohorts 1 and 2, respectively; median overall survival was 27.2 months (25.5-28.7 months) and 29.5 months (21.1 months to non-estimable). In both cohorts, median progression-free survival and overall survival decreased with increasing prior therapy lines. CONCLUSIONS: Cohort 2 results aligned with previous findings in Asian patients, supporting the manageable safety profile and use of T-DM1 in advanced BC.

Evaluation of IgM LAT and IgM ELISA as compared to microscopic agglutination test (MAT) for early diagnosis of Leptospira sp.

Leptospirosis is a worldwide zoonotic disease caused by spirochetes of the genus Leptospira. The clinical manifestation of leptospirosis is non-specific and frequently misdiagnosed as other illnesses. The aim of this study was to compare the diagnostic accuracies of two commercial tests for early diagnosis of Leptospira species: the IgM latex agglutination test (IgM LAT) and the IgM enzyme-linked immunosorbent assay (IgM ELISA). A total of 140 serum samples were obtained from patients suspected of leptospirosis at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC). These serum samples were tested for the presence of Leptospira sp. using IgM LAT, IgM ELISA and MAT. From Table 1, IgM LAT showed 21% (n = 29) positive, 18% (n = 25) inconclusive and 61% (n = 86) negative, while IgM ELISA showed 6% (n = 8) positive, 6% (n = 8) inconclusive, 88% (n = 124) negative and MAT showed 11% (n = 16) positive, 47% (n = 65) inconclusive, 42% (n = 59) negative. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of IgM LAT were 68.8%, 57.6%, 30.6% and 87.2% respectively, while for IgM ELISA they were 37.5%, 89.8%, 50% and 84.1%, respectively as compared to MAT (Table 2). The results showed that IgM LAT had higher sensitivity but lower specificity compared to IgM ELISA. In conclusion, IgM LAT can be useful as an early screening test for early diagnosis of Leptospira sp., while IgM ELISA is a suitable method for reducing false negative detection of Leptospira sp. As both tests show moderate percentages (~65%) in accuracy, an additional test is required for better detection of Leptospira sp.

Presence of methicillin resistance and heteroresistance among Coagulase Negative Staphylococci (CoNS) isolates obtained from Health Sciences students at a Public University.

This study was carried out to investigate the Coagulase Negative Staphylococci (CoNS) nasal carriage and the presence of methicillin resistant Coagulase Negative Staphylococci (MR-CoNS) among health sciences students at Faculty of Medicine and Health Sciences, Universiti Putra Malaysia. A total of 120 isolates of CoNS (62.5%) was isolated from 192 student volunteers. The mecA gene was detected in 15 isolates of CoNS (12.5%). Eight out of the 15 isolates of mecA positive CoNS were resistant to cefoxitin in disc diffusion test whereas the remaining seven isolates of mecA positive CoNS were susceptible to cefoxitin. Analysis of questionnaires showed no significant association between CoNS nasal carriage and the socio-demographic and risk factors except for the genders and history of cold (P < 0.050). Generally, this finding showed a relatively low level of methicillin resistance among CoNS nasal carriage from student volunteers.

Effect of dihydroergocristine on energy metabolism studied in the isolated perfused rat brain affected by ischemia and in neuroblastoma cells deprived of oxygen and glucose.

The effect of dihydroergocristine on energy metabolism was studied in the isolated perfused rat brain affected by ischemia and in cultivated C-1300 neuroblastoma cells deprived of oxygen and glucose. Creatine phosphate, ATP, ADP, AMP, glucose, glucose-6-phosphate, fructose-6-phosphate, fructose-1,6-diphosphate, pyruvate, and lactate were measured enzymatically. After a perfusion period of 30 min, the cortex of the isolated perfused rat brain exhibited an energy state not different from that in vivo. Dihydroergocristine added to the perfusion medium (5 mumol/L) did not influence these substrate levels under normal perfusion conditions. However, this drug was able to retard the breakdown of high-energy phosphates during ischemia and to accelerate the restoration of the energy state during the postischemic reperfusion period. The perfusion rate was not changed by the drug, and therefore it was assumed that dihydroergocristine could act directly on cell metabolism. This view was supported by the results obtained from experiments using cultivated N-2a neuroblastoma cells. These cells were incubated in a buffered salt solution deprived of glucose and oxygen for 15 min. Under these conditions, dihydroergocristine (2 mumol/L) added to the incubation medium caused changes in the concentrations or the high-energy phosphates similar to those in the isolated brain preparation: It increased the ATP concentration and decreased the ADP concentration significantly.

Comparison of rat brain and heart mitochondrial hexokinase solubilized by methohexital.

The purpose of the present investigation was to compare the solubilizing effect of methohexital on the mitochondrially bound hexokinase activity in brain and heart tissue of the rat. Experiments were performed using intact rats, the isolated perfused rat brain and heart as well as mitochondrial fractions from rat brain and heart tissue. It was shown that bound hexokinase activity was significantly solubilized by methohexital in brain tissue in vivo and in the isolated perfused rat brain but no effect was demonstrable in heart tissue. When mitochondrial fractions were incubated with methohexital in vitro, hexokinase activity was significantly solubilized from brain mitochondria but only slightly from heart mitochondria although glucose-6-phosphate was able to displace hexokinase also from heart mitochondria. The results suggest that mitochondrially bound hexokinase activity in brain tissue is particularly sensitive against the solubilizing effect of anesthetics. This effect could contribute to the sensitivity of brain function and metabolism against anesthetic drugs.

Presence of methicillin resistance and heteroresistance among Coagulase Negative Staphylococci (CoNS) isolates obtained from Health Sciences students at a Public University

This study was carried out to investigate the Coagulase Negative Staphylococci (CoNS) nasal carriage and the presence of methicillin resistant Coagulase Negative Staphylococci (MR-CoNS) among health sciences students at Faculty of Medicine and Health Sciences, Universiti Putra Malaysia. A total of 120 isolates of CoNS (62.5%) was isolated from 192 student volunteers. The mecA gene was detected in 15 isolates of CoNS (12.5%). Eight out of the 15 isolates of mecA positive CoNS were resistant to cefoxitin in disc diffusion test whereas the remaining seven isolates of mecA positive CoNS were susceptible to cefoxitin. Analysis of questionnaires showed no significant association between CoNS nasal carriage and the socio-demographic and risk factors except for the genders and history of cold (P < 0.050). Generally, this finding showed a relatively low level of methicillin resistance among CoNS nasal carriage from student volunteers.

P-31 nuclear magnetic resonance analysis of brain: II. Effects of oxygen deprivation on isolated perfused and nonperfused rat brain.

Phosphatic metabolite (perchloric acid extractable) concentrations of cerebral tissues were analyzed by phosphorus-31 nuclear magnetic resonance (P-31 NMR) spectroscopy following external perfusion of the isolated rat brain (30 min or 60 min) under the following conditions: (a) constant perfusion pressure with either fluorocarbon- or erythrocyte-based medium, and (b) constant perfusate flow rate (3 ml/min) with the erythrocyte-based medium. Metabolite concentrations of control perfused brains were compared with those in nonperfused controls to provide a basis for detecting any qualitative or quantitative changes in cerebral metabolite composition. Metabolic responses of perfused brains to ischemia (incomplete ischemia, 83% reduction in flow for 10 min; transient complete ischemia for 1.5 or 2 min) were evaluated immediately after the ischemic episode and at selected time points during reperfusion (3 and 15 min). Alterations in cerebral metabolite levels induced by hypoxia were analyzed using a nonperfused rat brain model. Irrespective of the perfusion method employed, the phosphatic metabolites of control perfused rat brains were identical quantitatively to those of the nonperfused controls. Cerebral ischemia resulted in significantly increased levels of ADP, AMP + IMP, Pi, fructose 1,6-diphosphate, and glycerol 3-phosphate (global ischemia only), whereas ATP and phosphocreatine (PCr) levels declined significantly. The magnitude of these changes varied with the severity of the ischemia; however, following 15 min of control reperfusion metabolite levels had reverted to preischemic values. Significant perturbations in tissue phosphoethanolamine (3.84 delta resonance) content were evident at various time points during ischemia and postischemic recovery, which varied according to the perfusion conditions. In contrast to the changes observed in response to ischemia, hypoxia affected only cerebral high-energy phosphate levels. ATP and PCr levels were reduced, while a concomitant, essentially equimolar, increase in Pi and ADP was observed. The present studies indicate that in terms of phosphatic metabolites, the control equilibrated isolated perfused rat brain is quantitatively and qualitatively indistinguishable from the nonperfused rat brain in vivo regardless of the perfusion conditions (constant flow versus constant pressure). The metabolic responses to ischemia and hypoxia, as measured by P-31 NMR, were consistent with the pattern of changes reported elsewhere. Overall, P-31 NMR spectroscopic evaluation of the intact rat brain provides a potential experimental context for dynamic measures of cerebral metabolism under exogenously controlled conditions. Th