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61.
Human cytomegalovirus (HCMV) possesses low pathogenic potential in an immunocompetent host. In the immunosuppressed host, however, a wide spectrum of infection outcomes, ranging from asymptomatic to life threatening, can follow either primary or nonprimary infection. The variability in the manifestations of HCMV infection in immunosuppressed individuals implies that there is a threshold of host antiviral immunity that can effectively limit disease potential. We used a nonhuman primate model of CMV infection to assess the relationship between CMV disease and the levels of developing anti-CMV immunity. Naive rhesus macaques were inoculated with rhesus cytomegalovirus (RhCMV) followed 2 or 11 weeks later by inoculation with pathogenic simian immunodeficiency virus SIVmac239. Two of four monkeys inoculated with SIV at 2 weeks after inoculation with RhCMV died within 11 weeks with simian AIDS (SAIDS), including activated RhCMV infection. Neither animal had detectable anti-SIV antibodies. The other two animals died 17 and 27 weeks after SIV inoculation with either SAIDS or early lymphoid depletion, although no histological evidence of activated RhCMV was observed. Both had weak anti-SIV antibody titers. RhCMV antibody responses for this group of monkeys were significantly below those of control animals inoculated with only RhCMV. In addition, all animals of this group had persistent RhCMV DNA in plasma and high copy numbers of RhCMV in tissues. In contrast, animals that were inoculated with SIV at 11 weeks after RhCMV infection rarely exhibited RhCMV DNA in plasma, had low copy numbers of RhCMV DNA in most tissues, and did not develop early onset of SAIDS or activated RhCMV. SIV antibody titers were mostly robust and sustained in these monkeys. SIV inoculation blunted further development of RhCMV humoral responses, unlike the normal pattern of development in control monkeys following RhCMV inoculation. Anti-RhCMV immunoglobulin G levels and avidity were slightly below control values, but levels maintained were higher than those observed following SIV infection at 2 weeks after RhCMV inoculation. These findings demonstrate that SIV produces long-lasting insults to the humoral immune system beginning very early after SIV infection. The results also indicate that anti-RhCMV immune development at 11 weeks after infection was sufficient to protect the host from acute RhCMV sequelae following SIV infection, in contrast to the lack of protection afforded by only 2 weeks of immune response to RhCMV. As previously observed, monkeys that were not able to mount a significant immune response to SIV were the most susceptible to SAIDS, including activated RhCMV infection. Rapid development of SAIDS in animals inoculated with SIV 2 weeks after RhCMV inoculation suggests that RhCMV can augment SIV pathogenesis, particularly during primary infection by both viruses.  相似文献   
62.
Lake Hayq was previously described as having exceptionally clearwater and very low phytoplankton biomass. It is now very different,with a shallow euphotic depth and abundant phytoplankton. Zooplanktonpopulations have changed as well; Daphnia and Diaphanosoma wererecorded before, whereas we found no Cladocera. Among the possiblecauses for this change in trophic status is the introductionof the planktivorous fish Oreochromis niloticus.  相似文献   
63.
Life cycle sustainability assessment (LCSA) can be used as a tool to understand how products and operating systems can meet the United Nations’ Sustainable Development Goals (SDGs). However, existing linkages between SDGs and LCSA are limited and an analysis of coverage in literature is needed. In this paper, we propose a generic methodological framework establishing connections between LCSA categories at micro-level and SDGs at macro-level based on derivation from the literature. The qualitative heuristic research method developed builds on keyword literature search, bibliometric analysis, mapping, and narrative literature review for connection rationales. By using qualitative assessment levels, an assessment of linkages between LCSA categories and SDGs reveal that “technology development,” “public commitment to sustainability issues,” “access to material resources,” and “education provided in the local community” have the highest number of reported relationships with SDGs. Twenty-two LCSA categories were found with no direct/indirect connection with any SDG; reasons include absence of life cycle thinking perspective in SDGs and lack of sustainability-based discussion for workers, consumers, and value chain actors' stakeholder groups. Despite these gaps, the results provide new insights for industries looking to measure the contribution of their product systems along their life cycle in the context of SDGs supporting them to some extent, to select LCSA categories with either highest number of identified relationships to SDGs or that contribute to prioritized list of SDGs. The approach provides a starting point to improve transparency and consistency of reporting of sustainability performance of product systems by connecting LCSA to the global agenda for sustainable development.  相似文献   
64.

Background

Appreciable evidence suggest that dysbiosis in microbiota, reflected in gut microbial imbalance plays a key role in the pathogenesis of neuropsychiatric disorders including depression and inflammatory diseases. Recently, the antidepressant properties of ketamine have gained prominence due to its fast and long lasting effects. Additional uses for ketamine in inflammatory disorders such as irritable bowel syndrome have been suggested. However, ketamine’s exact mechanism of action and potential effects on microbiome is not known. Here, we examined the effects of low dose ketamine, known to induce antidepressant effects, on stool microbiome profile in adult male Wistar rats. Animals (5/group) were injected intraperitoneally with ketamine (2.5?mg/kg) or saline, daily for 7?days and sacrificed on day 8 when intestinal stools were collected and stored at ??80?°C. DNA was extracted from the samples and the 16?S rRNA gene-based microbiota analysis was performed using 16S Metagenomics application.

Results

At genus–level, ketamine strikingly amplified Lactobacillus, Turicibacter and Sarcina by 3.3, 26 and 42 fold, respectively. Conversely, opportunistic pathogens Mucispirillum and Ruminococcus were reduced by approximately 2.6 and 26 fold, respectively, in ketamine group. Low levels of Lactobacillus and Turicibacter are associated with various disorders including depression and administration of certain species of Lactobacillus ameliorates depressive-like behavior in animal models. Hence, some of the antidepressant effects of ketamine might be mediated through its interaction with these gut bacteria. Additionally, high level of Ruminococcus is positively associated with the severity of irritable bowel syndrome (IBS), and some species of Mucispirillum have been associated with intestinal inflammation. Indirect evidence of anti-inflammatory role of Sarcina has been documented. Hence, some of the anti-inflammatory effects of ketamine and its usefulness in specific inflammatory diseases including IBS may be mediated through its interaction with these latter bacteria.

Conclusion

Our data suggest that at least some of the antidepressant and anti-inflammatory effects of daily ketamine treatment for 7?days may be mediated via its interaction with specific gut bacteria. These findings further validate the usefulness of microbiome as a target for therapeutic intervention and call for more detailed investigation of microbiome interaction with central mediators of mood and/or inflammatory disorders.
  相似文献   
65.

Background

Currently in Ethiopia, young people’s sexual and reproductive health services are limited and there is a growing issue of confidentiality and affordability of these health services. Moreover, the available services provided are not sensitive to the special needs of young people. Therefore, this study was aimed to assess young people’s sexual and reproductive health service utilization and its associated factors in Awabel district, Northwest Ethiopia.

Methods

A community based cross-sectional study was conducted among 781 randomly selected young people using a pre-tested structured questionnaires in Awabel district, Northwest Ethiopia. Data were entered into Epi data version 3.1 and analyzed using SPSS version 16.0 software.

Results

The mean age of respondents were 17.80 (+ 2.65) years. About 41% of young people had utilized sexual and reproductive health services. Young people from families of higher family expenditure, lived with mothers, participated in peer education and lived near to a Health Center were more likely to utilize sexual and reproductive health services. Furthermore, those who had a parental discussion on sexual and reproductive health (AOR (95% C.I): 2.23 (1.43, 3.46)) and ever had sexual intercourse (AOR (95% C.I): 1.88 (1.30, 2.71)) were more likely to utilize the service than their counterparts. On the other hand, those young people lived with their father and had a primary level of educational attainment was less likely to utilize the service.

Conclusion

Utilization of sexual and reproductive health services is low which needs a great attention where; if not intervened, young people might engage in risky sexual activities. Therefore, it needs a concerted effort from all the concerned bodies to improve their service utilization and thereby reduce the burden of young people’s disease and disabilities associated with sexual and reproductive health.  相似文献   
66.
The present study was carried out to determine an optimum honeybee colony’s carrying capacity of selected valleys dominated by Ziziphus spina-christi and Acacia tortilis in the Al-Baha region, Kingdom of Saudi Arabia. The study was conducted based on the assessment of the number of colonies kept, their productivities and the existing productive bee forage resources in the target valleys with its economic implication. In the existing beekeeping practice, the average number of managed honeybee colonies introduced per square kilometer was 530 and 317 during the flowering period of Z. spina-christi and A. tortilis, respectively. Furthermore, the overall ratios of productive bee forage plants to the number of honeybee colonies introduced were 0.55 and 11.12 to Ziziphus trees and A. tortilis shrubs respectively. In the existing situation the average honey production potential of 5.21 and 0.34 kg was recorded per Ziziphus and A. tortilis plants per flowering season, respectively. The present study, revealed that the number of honeybee colonies introduced in relation to the existing bee forage potential was extremely overcrowding which is beyond the carrying capacity of bee forage resources in selected valleys and it has been observed to affect the productivities and subsequent profitability of beekeeping. The study infers that, by keeping the optimum honeybee colony’s carrying capacity of valleys (88 traditional hives/km2 or 54 Langstroth hives/km2 in Ziziphus field and 72 traditional hives/km2 or 44 Langstroth hives/km2 in A. tortilis field), profitability of beekeeping can be boosted up to 130.39% and 207.98% during Z. spina-christi and A. tortilis, flowering seasons, respectively.  相似文献   
67.
68.
Improving productivity of maize (Zea mays L.) and water use efficiency is of great significance for agriculture in Ethiopia. In this study, the effects of ridge‐furrow with film mulch cultivation were tested on maize yields in Melkassa, Ethiopia. Three field experiments (drip irrigation, furrow irrigation and rainfed) were conducted each with randomised complete block design with three replicates. The drip irrigation experiment was conducted in the dry season and constituted three film mulch methods (non‐mulch, transparent film mulch and black film mulch) with three irrigation levels (357, 435 and 515 mm). The furrow irrigation experiment was also conducted in the dry season and constituted two film mulches (non‐mulch and transparent film mulch) with three irrigation levels (484, 674 and 865 mm). The rainfed experiment was conducted in the rainy season and constituted three mulches (non‐mulch, transparent film mulch and black film mulch) with two farming methods (ridge‐furrow farming and flat farming). In the drip irrigation experiment, the highest maize yields (5.9 ± 0.6 t ha?1) and irrigation water use efficiency (9.6 ± 1 kg ha?1 mm?1) were recorded in the treatment using black film mulch with high irrigation, with increases of 68% and 68.4% compared to using non‐mulch treatment at that irrigation level. In the furrow irrigation experiment, maize yields and irrigation water use efficiency reached 7 (± 0.8) t ha?1 and 9.1 (± 1.9) kg ha?1 mm?1 in the treatment using transparent film mulch with medium irrigation (674 mm), with increases of 46% and 46.8% compared to that with non‐mulch treatment. In the rainfed experiment, the film mulch rather than farming method had positive effects on the maize yields and rainwater use efficiency. The average maize yield reached 8.5 (± 0.7) t ha?1 in the film mulch treatments, with an increase of 39% than using the non‐mulch treatment. Compared with that of non‐mulch treatment, the net income in the film mulch treatments increased by 94% in the furrow experiment and 31% in the rainfed experiment. Our results indicate that the ridge‐furrow with film mulch system can be recommended for water‐saving irrigation with low cost in dry seasons, and film mulch with flat farming can be recommended in rainy seasons for maize production in Ethiopia. This study provides strong evidence that maize productivity can be effectively improved in Ethiopia and other similar areas of the world using this simple and cost‐effective technology.  相似文献   
69.
70.
BackgroundThe objectives of this study were to assess the heterogeneities of estimates and to estimate the seroprevalence of brucellosis in animals and humans in Ethiopia.ConclusionsThe seroprevalence of brucellosis is higher in goats than in other species. Its occurrence is evocative of its importance in the country in general and in the pastoral system in particular. Public awareness creation could reduce the transmission of Brucella spp. from animals to humans and the potential of livestock vaccination as a means of control of brucellosis needs to be assessed.  相似文献   
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