Stimulation of NADH oxidation by xanthine oxidase and polyvanadate in presence of some dehydrogenases and flavin compounds

The rates of NADH oxidation in presence of xanthine oxidase increase to a small and variable extent on addition of high concentrations of lactate dehydrogenase and other dehydrogenases. This heat stable activity is similar to polyvanadate-stimulation with respect to pH profile and SOD sensitivity. Isocitric dehydrogenase (NADP-specific) showed heat labile, SOD-sensitive polyvanadate-stimulated NADH oxidation activity. Polyvanadate-stimulated SOD-sensitive NADH oxidation was also found to occur with riboflavin, FMN and FAD in presence of a non-specific protein, BSA, suggesting that some flavoproteins may possess this activity.     

Pregnancies following long luteal phases in southern white rhinoceros (Ceratotherium simum simum)

All extant species in the Rhinocerotidae family are experiencing escalating threats in the wild, making self-sustaining captive populations essential genetic reservoirs for species survival. Assisted reproductive technologies (ARTs) will become increasingly important for achieving and maintaining ex situ population sustainability and genetic diversity. Previous reports have shown that a large proportion of captive southern white rhinoceros (SWR) females are irregularly cyclic or acyclic, and that cycling females display two different estrous cycle lengths of approximately 30 or 70 days. It has been suggested that the longer estrous cycle length is infertile or subfertile, as no term pregnancies have been observed following long cycles. Here we report the achievement of two pregnancies following long luteal phases, using ovulation induction and artificial insemination with either fresh or frozen-thawed semen. One female SWR conceived on the first insemination attempt and gave birth to a live offspring. A second female conceived twice in consecutive long cycles although the first embryo was resorbed by 33 days post-insemination. A pregnancy from this female's second insemination is ongoing with expected parturition in November 2019. Whether prolonged estrous cycles in SWR are subfertile or infertile in natural breeding situations remains unclear. However, our findings demonstrate that the application of ARTs following prolonged cycles can result the successful establishment of pregnancies in SWR. Therefore, with ARTs, female SWR otherwise considered nonreproductive due to long estrous cycles may still have the potential for representation and contribution to the ex situ population.     

Metabolic utilization of human osteoblast cell line hFOB 1.19 under normoxic and hypoxic conditions: A phenotypic microarray analysis

Osteoblasts play an important role in bone regeneration and repair. The hypoxia condition in bone occurs when bone undergoes fracture, and this will trigger a series of biochemical and mechanical changes to enable bone repair. Hence, it is interesting to observe the metabolites and metabolism changes when osteoblasts are exposed to hypoxic condition. This study has looked into the response of human osteoblast hFOB 1.19 under normoxic and hypoxic conditions by observing the cell growth and utilization of metabolites via Phenotype MicroArrays™ under these two different oxygen concentrations. The cell growth of hFOB 1.19 under hypoxic condition showed better growth compared to hFOB 1.19 under normal condition. In this study, osteoblast used glycolysis as the main pathway to produce energy as hFOB 1.19 in both hypoxic and normoxic conditions showed cell growth in well containing dextrin, glycogen, maltotriose, D-maltose, D-glucose-6-phospate, D-glucose, D-mannose, D-Turanose, D-fructose-6-phosphate, D-galactose, uridine, adenosine, inosine and α-keto-glutaric acid. In hypoxia, the cells have utilized additional metabolites such as α-D-glucose-1-phosphate and D-fructose, indicating possible activation of glycogen synthesis and glycogenolysis to metabolize α-D-glucose-1-phosphate. Meanwhile, during normoxia, D-L-α-glycerol phosphate was used, and this implies that the osteoblast may use glycerol-3-phosphate shuttle and oxidative phosphorylation to metabolize glycerol-3-phosphate.     

Use of the Population Grouping Methodology of the Canadian Institute for Health Information to predict high-cost health system users in Ontario

BACKGROUND:Prior research has consistently shown that the heaviest users account for a disproportionate share of health care costs. As such, predicting high-cost users may be a precondition for cost containment. We evaluated the ability of a new health risk predictive modelling tool, which was developed by the Canadian Institute for Health Information (CIHI), to identify future high-cost cases.METHODS:We ran the CIHI model using administrative health care data for Ontario (fiscal years 2014/15 and 2015/16) to predict the risk, for each individual in the study population, of being a high-cost user 1 year in the future. We also estimated actual costs for the prediction period. We evaluated model performance for selected percentiles of cost based on the discrimination and calibration of the model.RESULTS:A total of 11 684 427 individuals were included in the analysis. Overall, 10% of this population had annual costs exceeding $3050 per person in fiscal year 2016/17, accounting for 71.6% of total expenditures; 5% had costs above $6374 (58.2% of total expenditures); and 1% exceeded $22 995 (30.5% of total expenditures). Model performance increased with higher cost thresholds. The c-statistic was 0.78 (reasonable), 0.81 (strong) and 0.86 (very strong) at the 10%, 5% and 1% cost thresholds, respectively.INTERPRETATION:The CIHI Population Grouping Methodology was designed to predict the average user of health care services, yet performed adequately for predicting high-cost users. Although we recommend the development of a purpose-designed tool to improve model performance, the existing CIHI Population Grouping Methodology may be used — as is or in concert with additional information — for many applications requiring prediction of future high-cost users.

A substantial literature across health systems shows that the highest users of services account for disproportionate shares of the public costs of health care. It has recently been reported that more than three-quarters of individual health care costs in Ontario were incurred by just 10% of the population.¹ Similarly, an Ontario Ministry of Health and Long-Term Care (MOHLTC) analysis of inpatient and home care costs found that the top 5% of patients were responsible for 61% of spending in those domains.² Consistent findings have been reported for Manitoba, Alberta and British Columbia.^3–7Some of the highest-cost cases may be explained by rare, unpredictable events, but others arise in the presence of multiple chronic conditions. Research from the United States has suggested that spending on chronic conditions accounts for the majority of health care expenditures.⁸ Predicting high-cost users may help us to understand and better manage public spending on health care.Cognizant of this need, the Ontario MOHLTC developed a predictive model for high-cost users based on sociodemographic, utilization and clinical diagnostic characteristics.⁹ Although the model performed well, it relied on a coarse categorization of 20 diagnostic variables consisting of broadly defined chapters of the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) and a small number of chronic conditions, which limited its utility for explaining predictions. Moreover, this model is not available for use outside the MOHLTC. As such, there is a need for a predictive model that can be applied more widely by researchers and other stakeholders with an interest in health policy and spending in Canada.The Canadian Institute for Health Information (CIHI) has recently released a new population-based case mix product, the Population Grouping Methodology, which uses diagnoses obtained from patient health care encounters in multiple settings to summarize the universe of diagnosis codes into a clinically meaningful set of 226 health conditions. The grouping and modelling methodologies are described in more detail in Appendix 1 (available at www.cmaj.ca/lookup/suppl/doi:10.1503/cmaj.191297/-/DC1) and in previous reports.^10,11 The CIHI grouping methodology was not designed to predict high-cost cases, and previous work has already shown that the model performs better for low- and moderate-cost users than for highest-cost users (i.e., those with annual costs exceeding $25 000).¹¹ We evaluated the suitability of CIHI’s model for predicting future high-cost users in Ontario by examining the predicted costs for individuals who exceeded the top 10%, 5%, and 1% thresholds of actual cost.     

Addition of a small hydrophobic segment from the head region to an amphipathic leucine zipper like motif of E. coli toxin hemolysin E enhances the peptide-induced permeability of zwitterionic lipid vesicles

To find out the sequence requirement of the H-205 peptide, containing an amphipathic leucine zipper motif corresponding to the amino acid (a.a.) region 205-234 of hemolysin E (HlyE) to induce efficient permeation in zwitterionic lipid vesicles, the peptide was extended at the N-terminal after the addition of seven amino acids from the predicted transmembrane region in the head domain of the protein-toxin. The new peptide, H-198 (a.a. 198-234) and a scrambled mutant peptide of the same size were synthesized, fluorescently labeled and characterized functionally and structurally. The results showed that H-198 induced significantly higher permeation in the zwitterionic PC/Chol lipid vesicles than its shorter version, H-205. H-198 formed large aggregates in the PC/Chol vesicles unlike H-205 and also adopted more helical structure in the membrane mimetic environments compared to that of H-205. Fluorescence energy transfer experiments by flow cytometry indicated that only H-198 but not its mutant or H-205 oligomerized in the zwitterionic lipid vesicles, while in the negatively charged lipid vesicles both H-198 and H-205 formed oligomeric assembly. The results suggest a probable role of the hydrophobic residues of the head domain of HlyE in inducing permeability in the zwitterionic lipid vesicles by the peptide derived from the a.a. 198-234 of the toxin.     

Enhanced glutamate,IP3 and cAMP activity in the cerebral cortex of Unilateral 6-hydroxydopamine induced Parkinson's rats: Effect of 5-HT,GABA and bone marrow cell supplementation

Parkinson's disease is characterized by progressive cell death in the substantia nigra pars compacta, which leads to dopamine depletion in the striatum and indirectly to cortical dysfunction. Increased glutamatergic transmission in the basal ganglia is implicated in the pathophysiology of Parkinson's disease and glutamate receptor mediated excitotoxicity has been suggested to be one of the possible causes of the neuronal degeneration. In the present study, the effects of serotonin, gamma-aminobutyric acid and bone marrow cells infused intranigrally to substantia nigra individually and in combination on unilateral 6-hydroxydopamine induced Parkinson's rat model was analyzed. Scatchard analysis of total glutamate and NMDA receptor binding parameters showed a significant increase in B_max (P < 0.001) in the cerebral cortex of 6-hydroxydopamine infused rat compared to control. Real Time PCR amplification of NMDA2B, mGluR5, bax, and ubiquitin carboxy-terminal hydrolase were up regulated in cerebral cortex of 6-hydroxydopamine infused rats compared to control. Gene expression studies of GLAST, ά-Synuclien and Cyclic AMP response element-binding protein showed a significant (P < 0.001) down regulation in 6-OHDA infused rats compared to control. Behavioural studies were carried out to confirm the biochemical and molecular studies. Serotonin and GABA along with bone marrow cells in combination showed reversal of glutamate receptors and behaviour abnormality shown in the Parkinson's rat model. The therapeutic significance in Parkinson's disease is of prominence.