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OBJECTIVES: To investigate the association between added sugar and macronutrient and micronutrient intakes, and to assess whether added sugar intake is related to biochemical indices of nutritional status, Mini-Nutritional Assessment (MNA) score, body mass index (BMI) and performance on physical function tests. DESIGN: A cross-sectional, analytical study. SETTING AND SUBJECTS: Convenient sample of 285 institutionalised and community-dwelling black South African men and women aged 60+ y. METHODS: An interviewer-administered 24-h dietary recall and MNA were performed. Serum albumin, vitamin B12, ferritin, cholesterol, haemoglobin, red blood cell (RBC) folate and plasma vitamin C were measured. Handgrip strength, BMI, 'sit-to-stand' and 'get-up-and-go' tests were measured. Outcome variables were analysed according to tertiles of added sugar, in grams and as a percentage of total energy (% E). RESULTS: In each tertile of sugar intake, mean MNA score fell in the 'at-risk' classification. In women, energy, protein, % E protein, fibre, thiamin, riboflavin, niacin, vitamin B6, folate, pantothenic acid, biotin, vitamin C, calcium, iron, magnesium, phosphorus, zinc, copper and selenium intake were significantly lowest in subjects in the highest % E sugar tertile. In men, no differences were found for micronutrient intake according to tertiles of total added sugar or % E added sugar. Physical function declined with increasing sugar intake, and suboptimal RBC folate and plasma ascorbic acid status was associated with increasing sugar intake (in women). No relationship was found between added sugar intake and the very high prevalence (65%) of obesity in women. CONCLUSION: A nutrient-diluting effect of added sugars intake was demonstrated in elderly black South African women. Further studies in this population are required in order to develop food-based dietary guidelines, which include messages on added sugar intake.  相似文献   
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OBJECTIVE: To investigate whether MRI-based volumes of whole brain, medial temporal lobe and white matter hyperintensities (WMH) predict progression of cognitive decline in a sample of nondemented elderly. METHODS: Thirty-seven nondemented elderly attending a memory clinic and 28 elderly controls participated in this follow-up study. The average follow-up period was 1.8 years. Cognitive function was measured at baseline and follow-up with the Cambridge Cognitive Examination (CAMCOG). Baseline Magnetic Resonance Imaging (MRI) provided quantitative measures of whole brain, medial temporal lobe and WMH. Linear mixed models controlled for age and sex were used to assess the independent associations between MRI measures, baseline cognition, and annual decline in cognition. RESULTS: Medial temporal lobe volume was independently associated with baseline CAMCOG score (p < 0.01), whereas whole brain volume (p < 0.01) and WMH (p < 0.05) were associated with annual decline in CAMCOG score. CONCLUSIONS: These data suggest that regional damage to the medial temporal lobes underlies initial mild cognitive impairment, whereas more global brain changes, such as whole brain atrophy and WMH, contribute to further progression of cognitive decline.  相似文献   
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Objective   The aim of this study was to evaluate the efficacy of uterine artery embolisation (UAE) in myomatous uteri larger than 24 week's gestation (780 cm3).
Design   Prospective case contro study.
Setting   Universitas Hospital, University of the Free State, Bloemfontein, South Africa.
Population   Sixty-one women, who underwent UAE, were included in the study. The study group comprised of 12 women with uteri ≥780 cm3 and the control group 49 women with uteri <780 cm3.
Methods   UAE was performed and the difference in outcome for the two groups was determined at 12 months.
Main outcome measure   Symptomatic improvement with embolisation of the large uterus.
Results   Reduction of dysmenorrhoea, menorrhagia and pressure effects was similar for both groups. The median reduction in uterine volume (pre- to post-embolisation) was 188 cm3 (range 28–2038 cm3) with a 95% CI for the median difference for paired data of 146.5 and 236. Only 66% of the study group had, however, a reduction in volume to <780 cm3. The complication rates were similar for the two groups with regards to post-embolisation syndrome, fibroid slough, haematoma formation, infection, hysterectomy and failure to embolise. Satisfaction was similar between the two groups, with 91% of women satisfied with the procedure.
Conclusion   The large uterus does not decrease UAE's efficacy. Although 33.3% of the study group still had a uterus of ≥780 cm3, symptom reduction was still similar for both groups. Women may thus still be left with a large uterine volume but without symptoms. This must be taken into consideration when counselling women with an extremely large uterus for UAE.  相似文献   
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The study investigates the effect of zolpidem (CAS 82626-48-0) on brain injuries and cerebellar diaschisis. Four patients with varied brain injuries, three of them with cerebellar diaschisis, were imaged by 99mTc HMPAO Brain SPECT before and after application of zolpidem. The baseline SPECT before zolpidem showed poor tracer uptake in brain injury areas and cerebellar diaschisis. After zolpidem, cerebral perfusion through brain injury areas improved substantially in three patients and the cerebellar diaschisis was reversed. Observations point to a GABA based phenomenon that occurs in brain injury and diaschisis that is reversible by zolpidem.  相似文献   
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A comparison of DNA vaccines for the rabies-related virus,Mokola   总被引:6,自引:0,他引:6  
Nel LH  Niezgoda M  Hanlon CA  Morril PA  Yager PA  Rupprecht CE 《Vaccine》2003,21(19-20):2598-2606
Mokola virus, a rabies-related virus, has been reported to date from the African continent only. Like rabies virus, it is highly pathogenic, causes acute encephalitis, and zoonotic events have been documented. Although believed to be rare, there has been an unexplained increase in the number of isolations of the virus in South Africa in recent years. We have cloned and sequenced the glycoprotein (G) and nucleoprotein (N) genes from a South African Mokola virus, and used these in the construction of different DNA vaccines for immunization against Mokola virus. Four vaccines, utilizing different promoters and DNA backbone compositions, were generated and compared for efficacy in protection against Mokola virus. In one of these, both the Mokola virus G and N genes were co-expressed. Two of the single G-expressing DNA vaccines (based on pSG5 and pCI-neo, respectively) protected laboratory mice against lethal challenge, despite major differences in their promoters. However, neither vaccine was fully protective in a single immunization only. Serological assays confirmed titers of virus-neutralizing antibodies after immunization, which increased upon booster vaccine administration. A third construct (based on pBudCE4) was less effective in inducing a protective immune response, despite employing a strong CMV enhancer/promoter also used in the pCI-neo plasmid. Dual expression of Mokola virus G and N genes in pBudCE4 did not enhance its efficacy, under the conditions described. In addition, no significant utility could be demonstrated for a combined prime-boost approach, as no cross-protective immunity was observed against rabies or Mokola viruses from the use of pSG5-mokG or vaccinia-rabies glycoprotein recombinant virus vaccines, respectively, even though both vaccines provided 60-100% protection against homologous virus challenge.  相似文献   
39.
Since 1997, South Africa has been developing and implementing food-based dietary guidelines for people aged >6 years. The complexity of the population, which contains different ethnic groups, as well as the rapid urbanization that is taking place, means that food-based dietary guidelines need to consider both overnutrition and undernutrition. The initial guidelines did not include guidance on sugar, and the Department of Health was not prepared to approve them until appropriate guidance on sugar was included. This paper summarizes the evidence available for such a guideline and the nature of that evidence. Other low- and middle-income countries, particularly those in Africa, may face a similar dilemma and might learn from our experience.  相似文献   
40.
The objectives of this study were to determine whether differences in the size and composition of coarse (2.5-10 micro m), fine (< 2.5 microm), and ultrafine (< 0.1 microm) particulate matter (PM) are related to their uptake in macrophages and epithelial cells and their ability to induce oxidative stress. The premise for this study is the increasing awareness that various PM components induce pulmonary inflammation through the generation of oxidative stress. Coarse, fine, and ultrafine particles (UFPs) were collected by ambient particle concentrators in the Los Angeles basin in California and used to study their chemical composition in parallel with assays for generation of reactive oxygen species (ROS) and ability to induce oxidative stress in macrophages and epithelial cells. UFPs were most potent toward inducing cellular heme oxygenase-1 (HO-1) expression and depleting intracellular glutathione. HO-1 expression, a sensitive marker for oxidative stress, is directly correlated with the high organic carbon and polycyclic aromatic hydrocarbon (PAH) content of UFPs. The dithiothreitol (DTT) assay, a quantitative measure of in vitro ROS formation, was correlated with PAH content and HO-1 expression. UFPs also had the highest ROS activity in the DTT assay. Because the small size of UFPs allows better tissue penetration, we used electron microscopy to study subcellular localization. UFPs and, to a lesser extent, fine particles, localize in mitochondria, where they induce major structural damage. This may contribute to oxidative stress. Our studies demonstrate that the increased biological potency of UFPs is related to the content of redox cycling organic chemicals and their ability to damage mitochondria.  相似文献   
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