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31.
32.
BackgroundEbola virus disease is a highly virulent and transmissible disease. The largest recorded fatality from Ebola virus disease epidemic is ongoing in a few countries in West Africa, and this poses a health risk to the entire population of the world because arresting the transmission has been challenging. Vaccination is considered a key intervention that is capable of arresting further spread of the disease and preventing future outbreak. However, no vaccine has yet been approved for public use, although various recombinant vaccines are undergoing trials and approval for public use is imminent. Therefore, this study aimed to determine the acceptability of and willingness-to-pay for Ebola virus vaccine by the public.MethodsThe study was a community-based cross-sectional qualitative and quantitative interventional study conducted in two communities, each in two states in Nigeria. An interviewer-administered questionnaire was used to collect information on respondents’ knowledge of the Ebola virus, the ways to prevent the disease, and their preventive practices, as well as their acceptability of and willingness-to-pay for a hypothetical vaccine against Ebola virus disease. The association between acceptability of the vaccine and other independent variables were evaluated using multivariate regression analysis.ResultsEbola virus disease was considered to be a very serious disease by 38.5% of the 582 respondents (224/582), prior to receiving health education on Ebola virus and its vaccine. Eighty percent (80%) accepted to be vaccinated with Ebola vaccine. However, among those that accepted to be vaccinated, most would only accept after observing the outcome on others who have received the vaccine. More than 87.5% was willing to pay for the vaccine, although 55.2% was of the opinion that the vaccine should be provided free of charge.ConclusionThe level of acceptability of Ebola virus vaccine among respondents was impressive (though conditional), as well as their willingness to pay for it if the vaccine is not publicly funded. In order to achieve a high uptake of the vaccine, information and education on the vaccine should be extensively shared with the public prior to the introduction of the vaccine, and the vaccine should be provided free of charge by government.  相似文献   
33.
The T cell immunoglobulin mucin 3 (Tim-3) receptor is highly expressed on HIV-1-specific T cells, rendering them partially "exhausted" and unable to contribute to the effective immune mediated control of viral replication. To elucidate novel mechanisms contributing to the HTLV-1 neurological complex and its classic neurological presentation called HAM/TSP (HTLV-1 associated myelopathy/tropical spastic paraparesis), we investigated the expression of the Tim-3 receptor on CD8(+) T cells from a cohort of HTLV-1 seropositive asymptomatic and symptomatic patients. Patients diagnosed with HAM/TSP down-regulated Tim-3 expression on both CD8(+) and CD4(+) T cells compared to asymptomatic patients and HTLV-1 seronegative controls. HTLV-1 Tax-specific, HLA-A*02 restricted CD8(+) T cells among HAM/TSP individuals expressed markedly lower levels of Tim-3. We observed Tax expressing cells in both Tim-3(+) and Tim-3(-) fractions. Taken together, these data indicate that there is a systematic downregulation of Tim-3 levels on T cells in HTLV-1 infection, sustaining a profoundly highly active population of potentially pathogenic T cells that may allow for the development of HTLV-1 complications.  相似文献   
34.
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), infects one third of the world''s population. Among these infections, clinical isolates belonging to the W-Beijing appear to be emerging, representing about 50% of Mtb isolates in East Asia, and about 13% of all Mtb isolates worldwide. In animal models, infection with W-Beijing strain, Mtb HN878, is considered “hypervirulent” as it results in increased mortality and causes exacerbated immunopathology in infected animals. We had previously shown the Interleukin (IL) -17 pathway is dispensable for primary immunity against infection with the lab adapted Mtb H37Rv strain. However, it is not known whether IL-17 has any role to play in protective immunity against infection with clinical Mtb isolates. We report here that lab adapted Mtb strains, such as H37Rv, or less virulent Mtb clinical isolates, such as Mtb CDC1551, do not require IL-17 for protective immunity against infection while infection with Mtb HN878 requires IL-17 for early protective immunity. Unexpectedly, Mtb HN878 induces robust production of IL-1β through a TLR-2-dependent mechanism, which supports potent IL-17 responses. We also show that the role for IL-17 in mediating protective immunity against Mtb HN878 is through IL-17 Receptor signaling in non-hematopoietic cells, mediating the induction of the chemokine, CXCL-13, which is required for localization of T cells within lung lymphoid follicles. Correct T cell localization within lymphoid follicles in the lung is required for maximal macrophage activation and Mtb control. Since IL-17 has a critical role in vaccine-induced immunity against TB, our results have far reaching implications for the design of vaccines and therapies to prevent and treat emerging Mtb strains. In addition, our data changes the existing paradigm that IL-17 is dispensable for primary immunity against Mtb infection, and instead suggests a differential role for IL-17 in early protective immunity against emerging Mtb strains.  相似文献   
35.
Life cycle assessment of the supply and use of water in the Segura Basin   总被引:1,自引:0,他引:1  

Purpose

In this paper, the combined life cycle assessment of the water supply alternatives and the water use in a water-stressed watershed in Spain (the Segura) is presented. Although it is a dry area, agriculture and tourism are very profitable sectors with high water demands. Thus, external water supply alternatives including water transfers or desalination partly balance the reduced natural water availability to cover the existing water demands.

Methods

In order to integrate both the impact of water supply alternatives and water use, the ReCiPe method was used to assess the water supply alternatives at the endpoint approach with the three specific damage categories: human health, ecosystem diversity and damage to resources availability. At the same time, the water use impact was calculated and grouped in the same categories. Firstly, one average cubic metre of water at the user's gate in the Segura Basin area was taken as the functional unit. As irrigation and drinking water constitute the principal water uses, it was considered that to separately analyse 1 m3 used for irrigation and 1 m3 destined to drinking purposes could provide interesting information. Then, these units were also considered as functional units. Then, three additional hypothetical scenarios were introduced: two of them defined by a strong variability in rainfall and the third by a sudden diminution of water transferred from a neighbouring basin.

Results and discussion

Regarding the facilities to provide 1 m3 at user's gate in the Segura Basin, results showed that the seawater desalination plants obtained the highest score for all the three considered damage categories, followed by the Tajo–Segura water transfer, the groundwater, the local surface waters and the water reuse. In relation to the water use impact, the damage to ecosystems diversity was very representative with respect to the one coming from water supply infrastructures because irrigation constituted 85 % of the total demand.

Conclusions

The diversification of water supply alternatives within a region considerably increases any environmental impact, primarily stemming from the additional required infrastructures, and frequently from the use of external water sources for their uses. Thus, users and policy makers should be aware of the costs that a guaranteed water supply entails. In water-scarce territories, the use of external solutions such as desalination or water transfer either increase the environmental impact due to their high energy consumption or they are limited by existing climate variability. Therefore, they cannot be considered as the definite solution, which would be a balance between renewable sources and existing demands.  相似文献   
36.

Objectives

Depression is an adverse prognostic factor after an acute myocardial infarction (MI), and an increased propensity toward emotionally-driven myocardial ischemia may play a role. We aimed to examine the association between depressive symptoms and mental stress-induced myocardial ischemia in young survivors of an MI.

Methods

We studied 98 patients (49 women and 49 men) age 38–60 years who were hospitalized for acute MI in the previous 6 months. Patients underwent myocardial perfusion imaging at rest, after mental stress (speech task), and after exercise or pharmacological stress. A summed difference score (SDS), obtained with observer-independent software, was used to quantify myocardial ischemia under both stress conditions. The Beck Depression Inventory-II (BDI-II) was used to measure depressive symptoms, which were analyzed as overall score, and as separate somatic and cognitive depressive symptom scores.

Results

There was a significant positive association between depressive symptoms and SDS with mental stress, denoting more ischemia. After adjustment for demographic and lifestyle factors, disease severity and medications, each incremental depressive symptom was associated with 0.14 points higher SDS. When somatic and cognitive depressive symptoms were examined separately, both somatic [β = 0.17, 95% CI: (0.04, 0.30), p = 0.01] and cognitive symptoms [β = 0.31, 95% CI: (0.07, 0.56), p = 0.01] were significantly associated with mental stress-induced ischemia. Depressive symptoms were not associated with ischemia induced by exercise or pharmacological stress.

Conclusion

Among young post-MI patients, higher levels of both cognitive and somatic depressive symptoms are associated with a higher propensity to develop myocardial ischemia with mental stress, but not with physical (exercise or pharmacological) stress.  相似文献   
37.
An NAD(P)H-dependent oxidoreductase has been purified approximately 40-fold from the soluble protein fraction of the dissimilatory iron-reducing, anaerobic, thermophilic bacterium Carboxydothermus ferrireducens. The enzyme, a flavoprotein, has broad-substrate specificity—reducing Fe3+, Cr6+, and AQDS with rates of 0.31, 0.33, and 3.3 U mg−1 protein and calculated NADH oxidation turnover numbers of 0.25, 0.25, and 2.5 s−1, respectively. Numerous quinones are reduced via a two-electron transfer from NAD(P)H to quinone, thus participating in managing oxidative stress by avoiding the formation of semiquinone radicals.  相似文献   
38.
This study enrolled 125 premenopausal women diagnosed with bacterial vaginosis (BV) by presence of vaginal irritation, discharge and 'fishy' odor, and Nugent criteria and detection of sialidase enzyme. The subjects were treated with oral metronidazole (500 mg) twice daily from days 1 to 7, and randomized to receive oral Lactobacillus rhamnosus GR-1 (1 x 10(9)) and Lactobacillus reuteri RC-14 (1 x 10(9)) or placebo twice daily from days 1 to 30. Primary outcome was cure of BV as determined by normal Nugent score, negative sialidase test and no symptoms or signs of BV at day 30. A total of 106 subjects returned for 30-day follow-up, of which 88% were cured in the antibiotic/probiotic group compared to 40% in the antibiotic/placebo group (p<0.001). Of the remaining subjects, 30% subjects in the placebo group and none in the probiotic group had BV, while 30% in the placebo and 12% in the probiotic group fell into the intermediate category based upon Nugent score, sialidase result and clinical findings. High counts of Lactobacillus sp. (>10(5) CFU/ml) were recovered from the vagina of 96% probiotic-treated subjects compared to 53% controls at day 30. In summary, this study showed efficacious use of lactobacilli and antibiotic in the eradication of BV in black African women.  相似文献   
39.
The duration of development of immature stages of Aleyrodes proletella (L.) decreased with increase in temperature. The rate of the developmental time was smallest in the egg and largest in the second instar. The calculated threshold temperatures of development were approximately equal for the egg (10°) and the fourth-instar larva (10.4°) but differed significantly (P<0.05) from those of the first instar (7.3°), second instar (5°), and third instar (6.5°).
Zusammenfassung Die Entwicklungszeit des Eistadiums und der Larvenstadiums von Aleyrodes proletella nahm mit zunehmender Temperatur ab. Die relative tägliche Entwicklung war am geringsten beim Ei und am höchsten bei der Zweitlarve. Der berechnete Entwicklungsnullpunkt war ungefähr gleich für das Ei (10°) und für die Viertlarve (10,4°), während er für die Erstlarve (7,3°), für die Zweitlarve (5°) und für die Drittlarve (6,5°) etwas tiefer lag.
  相似文献   
40.
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