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Weight Variation (weight + variation)
Selected AbstractsIs there variability in drug release and physical characteristics of amiodarone chloride from different commercially available tablets?INTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 4 2010Possible therapeutic implications Abstract Objectives, Amiodarone is a low-solubility, high-permeability drug with a narrow therapeutic index and reported bioavailability problems associated with switching formulations. The aim of this study was to identify whether there is variability in drug release and physical characteristics of different commercially available amiodarone hydrochloride formulations in Australia. Methods, Four available formulations (innovator Cordarone (COR) and generic products G1, G2 and G3) were tested for drug dissolution, content uniformity, hardness, weight variation, friability and disintegration in accordance with the US Pharmacopeia specifications. Key findings, The tested formulations exhibited variable dissolution behaviours: G1 and G3 exhibited the fastest dissolution, G2 dissolution was the slowest and Cordarone showed a medium dissolution. After 3 months' exposure to high temperature (40 ± 2°C) and relative humidity (75 ± 5%), the products exhibited a higher degree of disparity, with drug-release profiles of the generics being markedly different from that of Cordarone. This suggests possible implications on bioequivalence for patients who live in warm/tropical regional areas. Most products met the US Pharmacopeia specifications for drug-content uniformity and other test physical characteristics. Conclusions, The results suggested that variability in drug release profiles in vitro of amiodarone formulations might be a potential indicator of compromised bioavailability, causing possible interference with the therapeutic response of the drug. [source] Climate predictability and breeding phenology in red deer: timing and synchrony of rutting and calving in Norway and FranceJOURNAL OF ANIMAL ECOLOGY, Issue 4 2005L. E. LOE Summary 1Timing and synchrony of reproduction are regarded as crucially important factors for fitness in seasonal environments. Natural selection has probably favoured temperate and arctic female herbivores that match reproduction with onset of plant growth in spring. However, breeding synchrony may also be affected by variation in phenotypic quality of females in a population, because females in poor body condition have been found to delay ovulation and subsequent calving. 2We compared breeding phenology, i.e. the timing and synchrony of rutting (roaring, sexual aggregation) and calving of red deer (Cervus elaphus L.) in France (latitude: 49°N) and Norway (latitude: 63°N). We hypothesized (H1) that calving and rutting were later at the site with latest onset of plant growth. 3We further quantified overall environmental predictability as the sum of annual constancy and seasonality and tested three different (not mutually exclusive) hypotheses about breeding synchrony: (H2a) the population experiencing most seasonal plant phenology should show the highest breeding synchrony; (H2b) overall predictability of plant phenology should determine breeding synchrony; and (H2c) breeding should be more synchronized in the population with lowest female body weight variation within age classes because they ovulate more synchronously. 4Calving and rutting, as well as onset of plant phenology, were later in Norway than in France, complying with the first hypothesis. Plant growth in spring was overall more predictable and also more seasonal in Norway than France. Hence we expected higher breeding synchrony in Norway than in France according to H2a and H2b. Variance in female body weight was slightly higher in France than in Norway, which should also cause more synchronized breeding in Norway than in France (H2c). Contrary to all predictions, variance in rutting and calving dates was around two times higher in Norway than in France. 5We suggest two alternative explanations of breeding synchrony. A more variable topography in Norway can make optimal birth date more variable on a local scale than in France, thereby maintaining a higher genetic variance for calving date in Norwegian red deer. Further, population age structure may play a role, as ovulation varies according to female age. Clearly, processes of breeding synchrony are far more complex than previously realized. [source] Germination is related to seed mass in grasses (Poaceae) of the eastern Qinghai-Tibetan Plateau, ChinaNORDIC JOURNAL OF BOTANY, Issue 5-6 2007Gaolin Wu Seed germination is a vulnerable stage in the plant life cycle. Many studies have focused on effects of seed mass on seed germination within a single species, but few studies have compared species of a common habitat. Poaceae plants are widely distributed on the Qinghai-Tibetan Plateau. We investigated how seed mass affect seed germination characters with forty-seven species of Poaceae typical to the alpine meadows of the eastern Qinghai-Tibetan plateau. The frequency of seed mass classes for these species produced a log-normal distribution. The weight of the seeds varied from 0.11 mg to 14.4 mg, and the weight variation nearly reached 103%. There were positive correlations between seed mass and germination index (R=0.331, p<0.05) and between seed mass and germination percentage (R=0.168, p>0.05). The results suggest that seed mass of the Poaceae family on the eastern Qinghai,Tibetan plateau is comparatively log-normal distributed as consistent with other studies, and the larger-seed species have faster germination than the smaller-seed species. Seed mass could be considered as one of the maintenance and construction mechanisms for plant communities in alpine meadows. [source] Low birth weight of contemporary African Americans: An intergenerational effect of slavery?AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2009Grazyna Jasienska The average birth weight in the contemporary African-American population is about 250 g lower than the average birth weight of European Americans. Differences in genetic and socioeconomic factors present between these two groups can explain only part of birth weight variation. I propose a hypothesis that the low birth weight of contemporary African Americans not only results from the difference in present exposure to lifestyle factors known to affect fetal development but also from conditions experienced during the period of slavery. Slaves had poor nutritional status during all stages of life because of the inadequate dietary intake accompanied by high energetic costs of physical work and infectious diseases. The concept of "fetal programming" suggests that physiology and metabolism including growth and fat accumulation of the developing fetus, and, thus its birth weight, depend on intergenerational signal of environmental quality passed through generations of matrilinear ancestors. I suggest that several generations that have passed since the abolition of slavery in the United States (1865) has not been enough to obliterate the impact of slavery on the current biological and health condition of the African-American population. Am. J. Hum. Biol., 2009. © 2008 Wiley-Liss, Inc. [source] Acrylate terpolymer in fabrication of medicated skin patchesPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 8 2001Vibha S. Mare Abstract An acrylate based pressure sensitive adhesive (PSA) was synthesized to design a drug-in-adhesive (DIA) type transdermal therapeutic system (TTS) for nitroglycerin used in the treatment of angina pectoris. 2-Ethylhexyl acrylate (EHA), methyl methacrylate (MMA) and acrylic acid (AA) were used to synthesize the PSA by free radical solution polymerization. The effects of reaction time, reaction temperature, initiator concentration and solvent on polymerization were studied. The synthesized terpolymer was characterized by 1H-NMR, FT-IR, differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) and also evaluated for intrinsic viscosity, refractive index, peel strength, moisture uptake and skin irritation potential. The PSA was used to develop DIA type patches of nitroglycerin. The patches were cast using solvent evaporation technique and dried at controlled temperature. The patches were evaluated for thickness uniformity, weight variation, peel strength and moisture pick-up. The percent drug content and in vitro drug release was determined by high pressure liquid chromatography (HPLC) method. On the basis of in vitro release profile, patches were selected for in vitro skin permeation studies. The developed formulation TP-1 (K,=,24.892 mcg/cm2/hr) followed zero-order rate kinetics and showed better skin permeation rate in comparison to the marketed TTS (MTTS) (K,=,17.413 mcg/cm2/hr). TP-1 was subjected to stability testing for a period of 1 year according to ICH guidelines. The patches were found to be stable and an expiry date of 2 years was predicted with storage at 25,°C or below. Copyright © 2001 John Wiley & Sons, Ltd. [source] Epinephrine for the treatment of anaphylaxis: do all 40 mg sublingual epinephrine tablet formulations with similar in vitro characteristics have the same bioavailability?BIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 9 2006Mutasem M. Rawas-Qalaji Abstract Epinephrine autoinjectors are underutilized in the first aid emergency treatment of anaphylaxis in the community; so non-invasive sublingual epinephrine administration is being proposed. In order to determine the effect of changing excipients on the bioavailability of sublingual epinephrine, four distinct fast-disintegrating epinephrine 40 mg tablet formulations, A, B, C and D, were manufactured using direct compression. All formulations were evaluated for tablet hardness (H), disintegration time (DT) and wetting time (WT). In a prospective 5-way crossover study, four sublingual formulations and epinephrine 0.3 mg i.m. as a control were tested sequentially in a validated rabbit model. Blood samples were collected before dosing and at intervals afterwards. Epinephrine plasma concentrations were measured using HPLC-EC. All tablet formulations met USP standards for weight variation and content uniformity, and resulted in similar mean H, DT and WT (n=6). The area under the curve (AUC), maximum concentration (Cmax) and time at which Cmax was achieved (Tmax) did not differ significantly after the sublingual administration of formulation A and epinephrine 0.3 mg i.m. The AUC after B, C and D were significantly lower (p<0.05) than after epinephrine 0.3 mg i.m. These results suggest that the selection of excipients used in these tablet formulations can affect the bioavailability of sublingually administered epinephrine. Copyright © 2006 John Wiley & Sons, Ltd. [source] Anti,tumour necrosis factor-, therapy increases body weight in patients with chronic plaque psoriasis: a retrospective cohort studyJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2008P Gisondi Abstract Background, Chronic plaque psoriasis is associated with overweight or obesity. Anti,tumour necrosis factor-, (anti-TNF-,) treatments are now frequently used in psoriasis management. TNF-, is deeply involved in body weight homeostasis, which may be affected by TNF-,,targeted therapy. Objective, To investigate whether anti-TNF-, treatments is associated with changes in body weight in patients with chronic plaque psoriasis. Methods, We performed a retrospective controlled analysis comparing the variations in body weight and body mass index (BMI) in three closed cohorts of psoriatic patients during a 6-month treatment with etanercept (N = 58), infliximab (N = 40) or methotrexate (N = 43). Results, We observed a body weight increment of 1.5 ± 2.7 kg (mean ± SD; P = 0.0002) and 2.5 ± 3.3 kg (P = 0.004) in patients treated with etanercept and infliximab, respectively. In contrast, a non-significant change (0.6 ± 1.4 kg; P = 0.4) was measured in patients treated with methotrexate. The BMI increased with 0.5 ± 0.5 (P = 0.01) and 0.8 ± 1 (P = 0.003) points in patients treated with etanercept and infliximab, respectively, whereas it did not change (< 0.2 ± 0.5; P = 0.06) in patients treated with methotrexate. About one fourth of patients experienced a 4- to 10-kg weight gain. Differences in body weight variations among patients treated with anti-TNF-, therapies and methotrexate were statistically significant (P = 0.0005). We could not identify clinical parameters predicting this phenomenon. Conclusions, Patients with psoriasis treated with long-term anti-TNF-, therapies may manifest a body weight gain. This effect should be taken into account in the global approach to patients with psoriasis. [source] | |||||||||||||