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Objectives: The objectives of this study were to explore inter-study heterogeneity in the pharmacokinetics (PK) of orally administered rifampicin, to derive summary estimates of rifampicin PK parameters at standard dosages and to compare these with summary estimates for higher dosages.Methods: A systematic search was performed for studies of rifampicin PK published in the English language up to May 2017. Data describing the Cmax and AUC were extracted. Meta-analysis provided summary estimates for PK parameter estimates at standard rifampicin dosages. Heterogeneity was assessed by estimation of the I2 statistic and visual inspection of forest plots. Summary AUC estimates at standard and higher dosages were compared graphically and contextualized using preclinical pharmacodynamic (PD) data.Results: Substantial heterogeneity in PK parameters was evident and upheld in meta-regression. Treatment duration had a significant impact on the summary estimates for rifampicin PK parameters, with Cmax 8.98 mg/L (SEM 2.19) after a single dose and 5.79 mg/L (SEM 2.14) at steady-state dosing, and AUC 72.56 mg·h/L (SEM 2.60) and 38.73 mg·h/L (SEM 4.33) after single and steady-state dosing, respectively. Rifampicin dosages of at least 25 mg/kg are required to achieve plasma PK/PD targets defined in preclinical studies.Conclusions: Vast inter-study heterogeneity exists in rifampicin PK parameter estimates. This is not explained by the available modifying variables. The recommended dosage of rifampicin should be increased to improve efficacy. This study provides an important point of reference for understanding rifampicin PK at standard dosages as efforts to explore higher dosing strategies continue in this field. [ABSTRACT FROM AUTHOR]

Drug-drug interactions between antiretroviral therapy and other drugs are well described. Gastric acid-reducing agents are one such class. However, few data exist regarding the frequency of and indications for prescription, nor risk assessment in the setting of an HIV cohort receiving antiretroviral therapy. To assess prevalence of prescription of gastric acid-reducing agents and drug-drug interaction within a UK HIV cohort, we reviewed patient records for the whole cohort, assessing demographic data, frequency and reason for prescription of gastric acid-reducing therapy. Furthermore, we noted potential drug-drug interaction and whether risk had been documented and mitigated. Of 701 patients on antiretroviral therapy, 67 (9.6%) were prescribed gastric acid-reducing therapy. Of these, the majority (59/67 [88.1%]) were prescribed proton pump inhibitors. We identified four potential drug-drug interactions, which were appropriately managed by temporally separating the administration of gastric acid-reducing agent and antiretroviral therapy, and all four of these patients remained virally suppressed. Gastric acid-reducing therapy, in particular proton pump inhibitor therapy, appears common in patients prescribed antiretroviral therapy. Whilst there remains a paucity of published data, our findings are comparable to those in other European cohorts. Pharmacovigilance of drug-drug interactions in HIV-positive patients is vital. Education of patients and staff, and accurate data-gathering tools, will enhance patient safety. [ABSTRACT FROM AUTHOR]

Alpine ecosystems are globally at risk from climate change. We use the International Union for the Conservation of Nature ( IUCN) Red List Criteria for ecosystems to assess the risk of ecosystem collapse in Australian alpine snow patch herbfields. These ecosystems occur on both mainland Australia and Tasmania. They are restricted to steep, south-easterly slopes where snow pack persists well into the summer growing season. Consequently, they are rare, and have high conservation significance. We evaluated the risk of snow patch herbfield 'ecosystem collapse' against criteria that accounted for the ecosystem's restricted distribution, projected decline in the snowpack and increased rates of invasion by taller growing native species of shrub and grass. Our analyses revealed considerable uncertainty in estimates of risk based on some criteria, particularly those related to thresholds of ecosystem collapse caused by biotic change. On the basis of the IUCN Red List criteria, we conclude that the ecosystem is 'endangered'. This is because of the restricted geographical distribution of the ecosystem, a substantial and highly likely decline in the abundance of snow (the principal abiotic driver of the ecosystem), and the prospect of invasion of much of the ecosystem by taller growing native shrubs and grasses. Our case study demonstrates the utility of the Red List methodology for assessing risks to biodiversity in rare ecosystems where changes to both abiotic factors and the relative dominance of native species constitute major threats. Our findings indicate the importance of snow patch herbfields as refugia for dwarf alpine plant species in the face of climate change, the need for continued monitoring, the removal of feral animals from the Australian Alps and scenario planning. [ABSTRACT FROM AUTHOR]

Kerry Stott and Fiona Cassells review the literature on the subject of weight gain from a biopsychosocial perspective. They describe the physiological changes that occur in the hypothalamus of patients taking clozapine affecting appetite and look at the behavioural factors that can influence food choice. [ABSTRACT FROM AUTHOR]

Outlines the logic used in a knowledge-based sequencing system for a hot-dip coating line (HDCL). Steel sequencing/scheduling applications; Details on the knowledge-based sequencing system; Outline of original knowledge-based system logic; Enhancements to the system; Results and implementation.

In 1984, Bethlehem Steel Corporation installed a new ingot mold stripping facility at its Bethlehem Plant that is capable of handling taller ingots. In order to take maximum advantage of this new facility, we developed a two-phase, computer-based procedure for selecting optimal ingot and internal ingot mold dimensions. Phase I of this procedure generates feasible ingot and internal ingot mold dimensions consistent with both the new stripper's capability and with mill constraints. Phase II then uses a set covering approach to select the optimal ingot and internal ingot mold sizes from among the feasible sizes generated. After analyzing the model, we recommended six new rectangular mold sizes to replace seven existing sizes. To date, implementation of these new ingot and mold sizes is proceeding smoothly and realizing the projected cost reduction benefits. [ABSTRACT FROM AUTHOR]

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cross and self pollen tubes were cultured in 'Victoria' plum flowers (Prunus domestica L.) at 5, 10, 15 and 20%deg;C. Pollen-tube lengths measured at intervals were fitted by S-shaped growth curves (logistic function) and the parameters of the curves used to derive a generalized model for pollen-tube growth based on accumulated temperatures. Above the threshold of 2.5°C, maximum growth rate was 0.34 mm per day-degree and the tubes reached half their final length at 16.6 day-degrees above 2.5°C. The model indicates that fertilization of plum flowers requires 16-20d at a constant temperature of 5°C after pollination, but only 3-4d at 15°C. Mathematical expressions based on the model are given for estimating pollen-tube penetration and growth rate from values of cumulated temperature since pollination, and for estimating the cumulated temperature necessary for pollen tubes to penetrate a given distance. Pollen-tube growth rates were the same in detached flowers, flowers attached to twigs, and flowers on young, grafted trees in pots. In detached flowers growth stopped before fertilization could occur, but some embryo sacs were fertilized in both the remaining treatments. Accurate pollen-tube growth assessments can therefore be made with detached flowers which are most convenient to use and can be accommodated in small incubators. Studies on fertilization, however, must use flowers on bulky and expensive grafted trees. [ABSTRACT FROM AUTHOR]

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coprinus atramentarius was grown on two commercial composts at a constant 20°C or with a cold shock (25°C→20°C) after 10 days. Cold shock was required for it to form fruiting bodies. [ABSTRACT FROM AUTHOR]