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Out-of-pocket (OOP) payments have severe consequences for health care access and utilisation and are especially catastrophic for the poor. Although women comprise the majority of the poor in Nigeria and globally, the implications of OOP payments for health care access from a gender perspective have received little attention. This study seeks to fill this gap by using a combination of quantitative and qualitative analysis to investigate the gendered impact of OOPs on healthcare utilisation in south-eastern Nigeria. 411 households were surveyed and six single-sex Focus Group Discussions conducted. This study confirmed the socioeconomic and demographic vulnerability of female-headed households (FHHs), which contributed to gender-based inter-household differences in healthcare access, cost burden, choices of healthcare providers, methods of funding healthcare and coping strategies. FHHs had higher cost burdens from seeking care and untreated morbidity than male-headed households (MHHs) with affordability as a reason for not seeking care. There is also a high utilisation of patent medicine vendors (PMVs) by both households (PMVs are drug vendors that are unregulated, likely to offer very low-quality treatment and do not have trained personnel). OOP payment was predominantly the means of healthcare payment for both households, and households spoke of the difficulties associated with repaying health-related debt with implications for the medical poverty trap. It is recommended that the removal of user fees, introduction of prepayment schemes, and regulating PMVs be considered to improve access and provide protection against debt for FHHs and MHHs. The vulnerability of widows is of special concern and efforts to improve their healthcare access and broader efforts to empower should be encouraged for them and other poor households.  相似文献   
84.
This study compared the responses of Avicennia marina and Trichilia dregeana seeds, both of which are recalcitrant, to partial dehydration and storage. Seeds of A. marina exhibited a faster rate of water and viability loss (± 50% viability loss in 4 days) during partial dehydration, compared with T. dregeana (± 50% viability loss in 14 days). In A. marina embryonic axes, reactive oxygen species (ROS) production peaked on 4 days of dehydration and was accompanied by an increase in the GSH:GSSG ratio; it appears that the glutathione system alone could not overcome dehydration-induced oxidative stress in this species. In A. marina, ROS and axis water content levels increased during hydrated storage and were accompanied by a decline in the GSH:GSSG ratio and rapid viability loss. In T. dregeana embryonic axes, ROS production (particularly hydrogen peroxide) initially increased and thereafter decreased during both partial dehydration and hydrated storage. Unlike in A. marina embryonic axes, this reduced ROS production was accompanied by a decline in the GSH:GSSG ratio. While T. dregeana seeds may have incurred some oxidative stress during storage, a delay in and/or suppression of the ROS-based trigger for germination may account for their significantly longer storage longevity compared with A. marina. Mechanisms of desiccation-induced seed viability loss may differ across recalcitrant-seeded species based on the rate and extent to which they lose water during partial drying and storage. While recalcitrant seed desiccation sensitivity and, by implication, storage longevity are modulated by redox metabolism, the specific ROS and antioxidants that contribute to this control may differ across species.  相似文献   
85.
Nano-drug delivery systems have proven to be an efficient formulation tool to overcome the challenges with current antibiotics therapy and resistance. A series of pH-responsive lipid molecules were designed and synthesized for future liposomal formulation as a nano-drug delivery system for vancomycin at the infection site. The structures of these lipids differ from each other in respect of hydrocarbon tails: Lipid1, 2, 3 and 4 have stearic, oleic, linoleic, and linolenic acid hydrocarbon chains, respectively. The impact of variation in the hydrocarbon chain in the lipid structure on drug encapsulation and release profile, as well as mode of drug interaction, was investigated using molecular modeling analyses. A wide range of computational tools, including accelerated molecular dynamics, normal molecular dynamics, binding free energy calculations and principle component analysis, were applied to provide comprehensive insight into the interaction landscape between vancomycin and the designed lipid molecules. Interestingly, both MM-GBSA and MM-PBSA binding affinity calculations using normal molecular dynamics and accelerated molecular dynamics trajectories showed a very consistent trend, where the order of binding affinity towards vancomycin was lipid4?>?lipid1?>?lipid2?>?lipid3. From both normal molecular dynamics and accelerated molecular dynamics, the interaction of lipid3 with vancomycin is demonstrated to be the weakest (?Gbinding?=??2.17 and ?11.57, for normal molecular dynamics and accelerated molecular dynamics, respectively) when compared to other complexes. We believe that the degree of unsaturation of the hydrocarbon chain in the lipid molecules may impact on the overall conformational behavior, interaction mode and encapsulation (wrapping) of the lipid molecules around the vancomycin molecule. This thorough computational analysis prior to the experimental investigation is a valuable approach to guide for predicting the encapsulation ability, drug release and further development of novel liposome-based pH-responsive nano-drug delivery system with refined structural and chemical features of potential lipid molecule for formulation development.  相似文献   
86.
One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various “outbreaks” of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus) collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin), in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight) were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River.  相似文献   
87.
The banana weevil, Cosmopolites sordidus, is the most important insect pest of banana and plantain in the world. Cultural control methods were investigated over 2 years in southern KwaZulu‐Natal, South Africa. Harvesting at ground level and dissection of remnants (treatment 1), and covering the base of the mat (entire plant consisting of several meristems) with soil and moving debris to the inter‐row (treatment 2), were compared to a positive control that involved treatment of plants with a registered pesticide (treatment 3), and a negative control that involved harvesting at 150 cm from the collar with no soil or sanitation amendments (treatment 4). Yield, weevil damage and pseudostem girth of plants were measured from August to November annually, while adult beetle densities were assessed over 4 weeks in October/November and April. Nematode samples were taken and analysed in October/November every year. Damage parameters included the coefficient of infestation, the percentage coefficient of infestation (PCI) at two intervals, the summed PCI value, the percentage cross‐sectional damage of the central cylinder and cortex, and the mean cross‐sectional damage percentage. A randomized block design with three replicates was used in the trial. The parameters were similar before the onset of the trial. Fruit yield and plant girth, corrected by nematode densities, were not significantly different in any treatment, nor were the nematodes controlled. Soil cover and recession of remnants was the only effective treatment, significantly reducing the CI, but not the adult density or the other damage parameters. Soil cover showed promise as a cultural control method because it only needs to be applied seasonally and reduced the percentage cross‐sectional damage of the central cylinder, the damage parameter most closely related to yield, by 14%.  相似文献   
88.
Heroin is an illicit opioid drug which is commonly abused and leads to dependence and addiction. Heroin is considered a pro-drug and is rapidly converted to its major active metabolite 6-monoacetylmorphine (6-MAM) which mediates euphoria and reward through the stimulation of opioid receptors in the brain. The aim of this study was to investigate the distribution and localization of 6-MAM in the healthy Sprague Dawley rat brain following intraperitoneal (i.p) administration of heroin (10 mg/kg), using matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI), in combination with quantification via liquid chromatography mass spectrometry (LC–MS/MS). These findings revealed that 6-MAM is present both in plasma and brain tissue with a Tmax of 5 min (2.8 µg/mL) and 15 min (1.1 µg/mL), respectively. MSI analysis of the brain showed high intensities of 6-MAM in the thalamus-hypothalamus and mesocorticolimbic system including areas of the cortex, caudate putamen, and ventral pallidum regions. This finding correlates with the distribution of opioid receptors in the brain, according to literature. In addition, we report a time-dependent distribution in the levels of 6-MAM, from 1 min with the highest intensity of the drug observed at 15 min, with sparse distribution at 45 min before decreasing at 60 min. This is the first study to use MSI as a brain imaging technique to detect a morphine’s distribution over time in the brain.  相似文献   
89.
Encapsulation of antibiotics into nanocarriers has the potential to overcome resistance and disadvantages associated with conventional dosage forms as well as increase half-life of an antibiotic. Encapsulation of meropenem (MRPN) into solid lipid nanoparticles (SLNs) remains unexplored among the limited work reported on nanoformulation incorporating MRPN. The study aimed to use an experimental design, to optimize MRPN-loaded SLNs, and to undertake in vitro and in silico evaluations. A Box-Behnken design (BBD) was used to optimize manufacturing conditions of glycerol monostearate (GMS) SLNs loaded with MRPN. The SLNs were prepared using hot homogenization and ultrasonication method. Optimized MRPN-SLNs showed particle size, zeta potential, and entrapment efficiency of 112.61?±?0.66 nm, ?20.43?±?0.99 mV, and 89.94?±?1.26%, respectively. The morphology of the SLNs revealed nearly spherical shaped particles. Differential scanning calorimetry and X-ray diffraction analysis showed that meropenem was present in amorphous form in the SLNs. Controlled in vitro MRPN release from SLNs was achieved and followed the Korsmeyer-Peppas model (R 2?=?0.9679). Prolonged in vitro antibacterial activity against Escherichia coli was also observed. The molecular modeling showed that both hydrophobic interactions and hydrogen bonding led to a stable MRPN-GMS complex formation, which was confirmed by its low heat of formation (?5536.13 kcal/mol). This stable complex could have contributed to the controlled release of MRPN from the SLNs and subsequent sustained antibacterial activity.  相似文献   
90.
Ho-Asjoe M  Govender R  Butler P 《Plastic and reconstructive surgery》2004,113(2):775; author reply 775-775; author reply 776
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