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81.
82.
Mohamed Khadar Abdi Daniela Lupi Ian C. W. Hardy 《Journal of evolutionary biology》2020,33(8):1068-1085
Kinship among interacting individuals is often associated with sociality and also with sex ratio effects. Parasitoids in the bethylid genus Goniozus are sub‐social, with single foundress females exhibiting post‐ovipositional maternal care via short‐term aggressive host and brood defence against conspecific females. Due to local mate competition (LMC) and broods normally being produced by a single foundress, sex ratios are female‐biased. Contests between adult females are, however, not normally fatal, and aggression is reduced when competing females are kin, raising the possibility of multi‐foundress reproduction on some hosts. Here, we screen for further life‐history effects of kinship by varying the numbers and relatedness of foundresses confined together with a host resource and also by varying the size of host. We confined groups of 1–8 Goniozus nephantidis females together with a host for 5+ days. Multi‐foundress groups were either all siblings or all nonsiblings. Our chief expectations included that competition for resources would be more intense among larger foundress groups but diminished by both larger host size and closer foundress relatedness, affecting both foundress mortality and reproductive output. From classical LMC theory, we expected that offspring group sex ratios would be less female‐biased when there were more foundresses, and from extended LMC theory, we expected that sex ratios would be more female‐biased when foundresses were close kin. We found that confinement led to the death of some females (11% overall) but only when host resources were most limiting. Mortality of foundresses was less common when foundresses were siblings. Developmental mortality among offspring was considerably higher in multi‐foundress clutches but was unaffected by foundress relatedness. Groups of sibling foundresses collectively produced similar numbers of offspring to nonsibling groups. There was little advantage for individual females to reproduce in multi‐foundress groups: single foundresses suppressed even the largest hosts presented and had the highest per capita production of adult offspring. Despite single foundress reproduction being the norm, G. nephantidis females in multi‐foundress groups appear to attune sex allocation according to both foundress number and foundress relatedness: broods produced by sibling foundresses had sex ratios similar to broods produced by single foundresses (ca. 11% males), whereas the sex ratios of broods produced by nonsibling females were approximately 20% higher and broadly increased with foundress number. We conclude that relatedness and host size may combine to reduce selection against communal reproduction on hosts and that, unlike other studied parasitoids, G. nephantidis sex ratios conform to predictions of both classical and extended LMC theories. 相似文献
83.
Yu Yao Aden Ka-Yin Chan Zhi Yong Qin Ling Chao Chen Xin Zhang Jesse Chung-Sean Pang Hiu Ming Li Yin Wang Ying Mao Ho-Keung NG Liang Fu Zhou 《PloS one》2013,8(6)
Recurrence and progression to higher grade lesions are characteristic behaviorsof gliomas. Though IDH1 mutation frequently occurs and is considered as an early event in gliomagenesis, little is known about its role in the recurrence and progression of gliomas. We therefore analysed IDH1 and IDH2 statusat codon 132 of IDH1 and codon 172 of IDH2 by direct sequencing and anti-IDH1-R132H immunohistochemistry in 53 paired samples and their recurrences, including 29 low- grade gliomas, 16 anaplastic gliomas and 8 Glioblastomas. IDH1/IDH2 mutation was detected in 32 primarytumors, with 25 low- grade gliomas and 6 anaplastic gliomas harboring IDH1 mutation and 1 low- grade glioma harboring IDH2 mutation. All of the paired tumors showed consistent IDH1 and IDH2 status. Patients were analyzed according to IDH1 status and tumor-related factors. Malignant progression at recurrence was noted in 22 gliomas and was not associated with IDH1 mutation. Survival analysis revealed patients with IDH1 mutated gliomas had a significantly longer progression-free survival (PFS) and overall survival (OS). In conclusion, this study demonstrated a strong tendency of IDH1/IDH2 status being consistent during progression of glioma. IDH1 mutation was not a predictive marker for malignant progression and it was a potential prognostic marker for gliomas of Chinese patients. 相似文献
84.
85.
Khalaj L Peirovi H Khodagholi F Abdi A Dargahi L Ahmadiani A 《Neurochemical research》2011,36(2):268-280
Postoperative neurologic deficit due to spinal cord ischemia-reperfusion (I/R) injury is the most devastating complication
following thoracoabdominal aortic aneurysm repairs. The protective potential for 17β-Estradiol has not been yet studied in
such injury. In this study, ischemia induction for 18 min in male New Zealand White rabbits resulted in the highest percentage
(80%) of biphasic paraplegic outcome assessed by Tarlov’s score. Acute Estradiol pretreatment (1 mg/kg, i.p., 30 min before
I/R induction) altered this outcome and significantly prevented the worsening pattern of neurologic deficits over 48 h of
observation. Histopathologic and oxidative stress evaluations of lumbar spinal cords taken in delayed permanent paraplegic
phase (48 h after ischemia induction), further confirmed protective efficacy of Estradiol in such context. In western blot
analysis, the expression of cleaved caspase-3 and heat shock protein 70 declined in Estradiol pretreated group compared to
ischemic control group. TUNEL assay also showed the efficacy of Estradiol to abate motor neuron apoptosis. Interestingly,
Estradiol respectively increased and decreased the expression of Cyclooxygenase (COX)-1 and COX-2, to a significant extent.
Estradiol, exerting its protection through affecting one or a combination of involved biochemical factors can constitute a
potential candidate to protect against thoracoabdominal aortic aneurysm repairs induced spinal cord I/R injury. 相似文献
86.
The active catalysts for the enantioselective ring opening (ARO) of meso-stilbene oxide, cis-butene oxide, cyclohexene oxide, cyclopentene oxide, and cyclooctene oxide with various substituted anilines were generated in situ by the reaction of Ti(O(i)Pr)(4) with poly-[(R,R)-N,N'-bis-{3-(1,1-dimethylethyl)-5-methylene salicylidene} cyclohexane-1,2-diamine]-1 and (1R,2R)-N,N'-bis[3,5-di(tert-butyl)salicylidene] cyclohexane-1,2-diamine-2. These catalysts in the presence of nonracemic imine as an additive provided β-amino alcohol in excellent yield (99%) and chiral purity (enantiomeric excess (ee) up to 99%) for the ARO of meso-stilbene oxide with aniline. The same protocol was less effective for the ARO of cyclic epoxides; however, when triphenylphosphine was used as an additive, there was a significant improvement in catalyst performance for the ARO of cyclohexene oxide (yield, 85-90%; ee, 63-67%). Both in situ generated polymeric and monomeric catalysts performed in a similar manner except that the polymeric catalyst Ti(IV)-1 was more active and recycled several times with retention of enantioselectivity when compared with the monomeric catalyst Ti(IV)-2, which was nonrecyclable. 相似文献
87.
88.
Supakit Paosen Sakkarin Lethongkam Suttiwan Wunnoo Nussana Lehman Ekwipoo Kalkornsurapranee Abdi Wira Septama Supayang Piyawan Voravuthikunchai 《Biotechnology journal》2021,16(9):2100030
Failure in the prevention of cross-transmission from contaminated gloves has been recognized as an important factor that contributes to the spread of several healthcare-associated infections. Ex situ coating process with silver nanoparticles (AgNPs) using Eucalyptus citriodora ethanolic leaf extract as reducing and capping agents to coat glove surfaces has been developed to prevent this mode of transmission. Elemental analysis of coated gloves showed 24.8 Wt% silver densely adhere on the surface. The coated gloves fully eradicated important hospital-acquired pathogens including Gram-positive bacteria, Gram-negative bacteria, and yeasts within 1 h. The coated gloves showed significant reduction, an average of five logs when tested against all standard strains and most clinical isolates (p < 0.01). Following prolonged exposure, the coating significantly reduced the numbers of most adhered pathogenic species, compared with uncoated gloves (p < 0.0001). AgNPs-coated gloves reduced microbial adhesion of mixed-species biofilms. A series of contamination and transmission assays demonstrated no transmission of viable organisms. Biocompatibility analysis confirmed high viability of HaCaT and L929 cells at all concentrations of AgNPs tested. The coated gloves were non-toxic with direct contact with L929 cells. The highly efficacious AgNPs-coated gloves potentially provide additional protection against transmission of healthcare-associated infections. 相似文献
89.
A new sensing area for a sensor based on surface plasmon resonance (SPR) was fabricated to detect trace amounts of mercury and lead ions. The gold surface used for SPR measurements were modified with polypyrrole-chitosan (PPy-CHI) conducting polymer composite. The polymer layer was deposited on the gold surface by electrodeposition. This optical sensor was used for monitoring toxic metal ions with and without sensitivity enhancement by chitosan in water samples. The higher amounts of resonance angle unit (ΔRU) were obtained for PPy-CHI film due to a specific binding of chitosan with Pb(2+) and Hg(2+) ions. The Pb(2+) ion bind to the polymer films most strongly, and the sensor was more sensitive to Pb(2+) compared to Hg(2+). The concentrations of ions in the parts per million range produced the changes in the SPR angle minimum in the region of 0.03 to 0.07. Data analysis was done by Matlab software using Fresnel formula for multilayer system. 相似文献
90.
Meijaard E Buchori D Hadiprakarsa Y Utami-Atmoko SS Nurcahyo A Tjiu A Prasetyo D Nardiyono Christie L Ancrenaz M Abadi F Antoni IN Armayadi D Dinato A Ella Gumelar P Indrawan TP Kussaritano Munajat C Priyono CW Purwanto Y Puspitasari D Putra MS Rahmat A Ramadani H Sammy J Siswanto D Syamsuri M Andayani N Wu H Wells JA Mengersen K 《PloS one》2011,6(11):e27491
Human-orangutan conflict and hunting are thought to pose a serious threat to orangutan existence in Kalimantan, the Indonesian part of Borneo. No data existed prior to the present study to substantiate these threats. We investigated the rates, spatial distribution and causes of conflict and hunting through an interview-based survey in the orangutan's range in Kalimantan, Indonesia. Between April 2008 and September 2009, we interviewed 6983 respondents in 687 villages to obtain socio-economic information, assess knowledge of local wildlife in general and orangutan encounters specifically, and to query respondents about their knowledge on orangutan conflicts and killing, and relevant laws. This survey revealed estimated killing rates of between 750 and 1800 animals killed in the last year, and between 1950 and 3100 animals killed per year on average within the lifetime of the survey respondents. These killing rates are higher than previously thought and are high enough to pose a serious threat to the continued existence of orangutans in Kalimantan. Importantly, the study contributes to our understanding of the spatial variation in threats, and the underlying causes of those threats, which can be used to facilitate the development of targeted conservation management. 相似文献