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A Arimura C A Meyers W L Case W A Murphy A V Schally 《Biochemical and biophysical research communications》1979,89(3):913-918
The 1:1 Cu(II), Co(II), Co(II)-O2, Fe(II)-NO, and Fe(III) complexes of depBLM have been investigated by ESR spectroscopy and compared with the corresponding metal complexes of BLM. DepBLM which lacks the α-amino group of β-aminoalanine portion in BLM molecule, forms the metal complexes different from BLM with regard to the fifth axial donor. In addition, the formation of hydroxyl radical by the depBLM-Fe(II) complex is remarkably lower than that by the BLM-Fe(II) complex. This study indicates an important effect of fifth axial nitrogen on metal coordination and oxygen activation of BLM. 相似文献
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Gertrude Membang Zachee Ambang Hermine Claudine Mahot Apollin Fotso Kuate Komi Kouma Mokpokpo Fiaboe Rachid Hanna 《Journal of Applied Entomology》2020,144(6):468-480
Management of the banana root borer (BRB), Cosmopolites sordidus (Germar; Coleoptera: Curculionidae), remains a challenge in banana and plantain production worldwide. Synthetic pesticides remain the most widely used solution while mycoinsecticides are increasingly being recommended. In this study, we selected indigenous isolates of Beauveria bassiana and Metarhizium anisopliae collected from plantain fields in Cameroon, and tested them in the laboratory for their viability, pathogenicity and virulence against all C. sordidus life stages. Of 13 isolates initially screened for spore germination and pathogenicity to adult weevils in conidial suspension of 3.2 × 108 conidia/ml, eight isolates with high to moderate germination and highest weevil mortality were selected for dose–response bioassays with four concentrations per isolate: 3.2 × 102, 3.2 × 104, 3.2 × 106 and 3.2 × 108 conidia/ml. The virulent isolates from adult bioassays were tested with eggs, larva and pupae in conidial suspension of 3.2 × 108 conidia/ml. Isolates performance depended on insect life stage with significantly high pathogenicity and virulence against larval, pupa and adult stages. The Beauveria isolate BIITAC6.2.2 caused the highest mortality rates followed by MIITAC1.1.5. Lethal times and lethal concentrations were relatively low for the three M. anisopliae isolates and three B. bassiana isolates which were the best isolates in almost all insect life stages. Apart from being effective in multiple life stages, these isolates were transmitted horizontally from one stage to another when eggs and pupae were treated. The implication of these findings for integrated management of the BRB, and potential biopesticides development and commercialization are discussed. 相似文献
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Muhamadi Lubega Neema Nakyaanjo Sumaya Nansubuga Edgar Hiire Godfrey Kigozi Gertrude Nakigozi Tom Lutalo Fred Nalugoda David Serwadda Ronald Gray Maria Wawer Caitylin Kennedy Steven James Reynolds 《PloS one》2015,10(8)
Background
In Kasensero fishing community, home of the first recorded case of HIV in Uganda, HIV transmission is still very high with an incidence of 4.3 and 3.1 per 100 person-years in women and men, respectively, and an HIV prevalence of 44%, reaching up to 74% among female sex workers. We explored drivers for the high HIV transmission at Kasensero from the perspective of fishermen and other community members to inform future policy and preventive interventions.Methods
20 in-depth interviews including both HIV positive and HIV negative respondents, and 12 focus-group discussions involving a total of 92 respondents from the Kasensero fishing community were conducted during April-September 2014. Content analysis was performed to identify recurrent themes.Results
The socio-economic risk factors for high HIV transmission in Kasensero fishing community cited were multiple and cross-cutting and categorized into the following themes: power of money, risk denial, environmental triggers and a predisposing lifestyle and alcoholism and drug abuse. Others were: peer pressure, poor housing and the search for financial support for both the men and women which made them vulnerable to HIV exposure and or risk behavior.Conclusions
There is a need for context specific combination prevention interventions in Kasensero that includes the fisher folk and other influential community leaders. Such groups could be empowered with the knowledge and social mobilization skills to fight the negative and risky behaviors, perceptions, beliefs, misconceptions and submission attitudes to fate that exposes the community to high HIV transmission. There is also need for government/partners to ensure effective policy implementation, life jackets for all fishermen, improve the poor housing at the community so as to reduce overcrowding and other housing related predispositions to high HIV rates at the community. Work place AIDS-competence teams have been successfully used to address high HIV transmission in similar settings. 相似文献259.
Laure K Case Emma H Wall Erin E Osmanski Julie A Dragon Naresha Saligrama James F Zachary Bernardo Lemos Elizabeth P Blankenhorn Cory Teuscher 《Genome biology》2015,16(1)
BackgroundThe prevalence of some autoimmune diseases is greater in females compared with males, although disease severity is often greater in males. The reason for this sexual dimorphism is unknown, but it may reflect negative selection of Y chromosome-bearing sperm during spermatogenesis or male fetuses early in the course of conception/pregnancy. Previously, we showed that the sexual dimorphism in experimental autoimmune encephalomyelitis (EAE) is associated with copy number variation (CNV) in Y chromosome multicopy genes. Here, we test the hypothesis that CNV in Y chromosome multicopy genes influences the paternal parent-of-origin effect on EAE susceptibility in female mice.ResultsWe show that C57BL/6 J consomic strains of mice possessing an identical X chromosome and CNV in Y chromosome multicopy genes exhibit sperm head abnormalities and female-biased sex ratio. This is consistent with X-Y intragenomic conflict arising from an imbalance in CNV between homologous X:Y chromosome multicopy genes. These males also display paternal transmission of EAE to female offspring and differential loading of microRNAs within the sperm nucleus. Furthermore, in humans, families of probands with multiple sclerosis similarly exhibit a female-biased sex ratio, whereas families of probands affected with non-sexually dimorphic autoimmune diseases exhibit unbiased sex ratios.ConclusionsThese findings provide evidence for a mechanism at the level of the male gamete that contributes to the sexual dimorphism in EAE and paternal parent-of-origin effects in female mice, raising the possibility that a similar mechanism may contribute to the sexual dimorphism in multiple sclerosis.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0591-7) contains supplementary material, which is available to authorized users. 相似文献260.
Gavin Lear Julia Bellamy Bradley S Case Jack E Lee Hannah L Buckley 《The ISME journal》2014,8(8):1715-1726
The extent to which non-host-associated bacterial communities exhibit small-scale biogeographic patterns in their distribution remains unclear. Our investigation of biogeography in bacterial community composition and function compared samples collected across a smaller spatial scale than most previous studies conducted in freshwater. Using a grid-based sampling design, we abstracted 100+ samples located between 3.5 and 60 m apart within each of three alpine ponds. For every sample, variability in bacterial community composition was monitored using a DNA-fingerprinting methodology (automated ribosomal intergenic spacer analysis) whereas differences in bacterial community function (that is, carbon substrate utilisation patterns) were recorded from Biolog Ecoplates. The exact spatial position and dominant physicochemical conditions (for example, pH and temperature) were simultaneously recorded for each sample location. We assessed spatial differences in bacterial community composition and function within each pond and found that, on average, community composition or function differed significantly when comparing samples located >20 m apart within any pond. Variance partitioning revealed that purely spatial variation accounted for more of the observed variability in both bacterial community composition and function (range: 24–38% and 17–39%) than the combination of purely environmental variation and spatially structured environmental variation (range: 17–32% and 15–20%). Clear spatial patterns in bacterial community composition, but not function were observed within ponds. We therefore suggest that some of the observed variation in bacterial community composition is functionally ‘redundant''. We confirm that distinct bacterial communities are present across unexpectedly small spatial scales suggesting that populations separated by distances of >20 m may be dispersal limited, even within the highly continuous environment of lentic water. 相似文献