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41.
The blue-green eggshell pigment biliverdin is an efficient antioxidant, the deposition of which may be costly and act as a handicap to the female's antioxidant capacity. Thus, it is hypothesized that there exists a positive correlation between the degree of eggshell coloration and the condition and health state of the mother. In this study, we measured the blue-green chroma of collared flycatcher Ficedula albicollis eggs, and investigated the associations between egg colour and parental characteristics, laying date, clutch size and laying order. We also analysed the possible correlations between egg size, yolk carotenoid and antibody levels and eggshell pigmentation. Our results revealed no significant relationships between egg colour and female age, morphological and serological variables. Blue-green colour intensity of eggs increased throughout the breeding season, which could be the result of either a proximate constraint or an adaptive strategy. We found a positive association between egg colour saturation and yolk lutein concentration. This relationship could be the result of the seasonal improvement of caterpillar supply, which could influence the deposition of both components into the egg. Furthermore, we found that females mated to lower-quality males produced eggs with higher biliverdin pigmentation. It is possible that deposition of biliverdin is correlated to some unmeasured aspect of egg quality that could enhance the viability of offspring of lower-quality fathers. We found that intensity of blue-green coloration increased with laying order between the first and fifth eggs. 相似文献
42.
JeeNa Hwang Jinjie Li Wing-Yee Liu Song-Ji An Hwajin Cho Nam Han Her Inhwa Yeam Dosun Kim Byoung-Cheorl Kang 《Molecules and cells》2009,27(3):329-336
To evaluate the involvement of translation initiation factors eIF4E and eIFiso4E in Chilli veinai mottle virus (ChiVMV) infection in pepper, we conducted a genetic analysis using a segregating population derived from a cross between
Capsicum annuum ‘Dempsey’ containing an eIF4E mutation (pvr1
2
) and C. annuum ‘Perennial’ containing an eIFiso4E mutation (pvr6). C. annuum ‘Dempsey’ was susceptible and C. annuum ‘Perennial’ was resistant to ChiVMV. All F1 plants showed resistance, and F2 individuals segregated in a resistant-susceptible ratio of 166:21, indicating that many resistance loci were involved. Seventy-five
F2 and 329 F3 plants of 17 families were genotyped with pvr1
2
and pvr6 allele-specific markers, and the genotype data were compared with observed resistance to viral infection. All plants containing
homozygous genotypes of both pvr1
2
and pvr6 were resistant to ChiVMV, demonstrating that simultaneous mutations in eIF4E and eIFiso4E confer resistance to ChiVMV in pepper. Genotype analysis of F2 plants revealed that all plants containing homozygous genotypes of both pvr1
2
and pvr6 showed resistance to ChiVMV. In protein-protein interaction experiments, ChiVMV viral genome-linked protein (VPg) interacted
with both eIF4E and eIFiso4E. Silencing of eIF4E and eIFiso4E in the VIGS experiment showed reduction in ChiVMV accumulation. These results demonstrated that ChiVMV can use both eIF4E
and eIFiso4E for replication, making simultaneous mutations in eIF4E and eIFiso4E necessary to prevent ChiVMV infection in pepper.
These authors contributed equally to this work. 相似文献
43.
Lisa F. P. Ng Angela Chow Yong-Jiang Sun Dyan J. C. Kwek Poh-Lian Lim Frederico Dimatatac Lee-Ching Ng Eng-Eong Ooi Khar-Heng Choo Zhisheng Her Philippe Kourilsky Yee-Sin Leo 《PloS one》2009,4(1)
Background
Little is known about the immunopathogenesis of Chikungunya virus. Circulating levels of immune mediators and growth factors were analyzed from patients infected during the first Singaporean Chikungunya fever outbreak in early 2008 to establish biomarkers associated with infection and/or disease severity.Methods and Findings
Adult patients with laboratory-confirmed Chikungunya fever infection, who were referred to the Communicable Disease Centre/Tan Tock Seng Hospital during the period from January to February 2008, were included in this retrospective study. Plasma fractions were analyzed using a multiplex-microbead immunoassay. Among the patients, the most common clinical features were fever (100%), arthralgia (90%), rash (50%) and conjunctivitis (40%). Profiles of 30 cytokines, chemokines, and growth factors were able to discriminate the clinical forms of Chikungunya from healthy controls, with patients classified as non-severe and severe disease. Levels of 8 plasma cytokines and 4 growth factors were significantly elevated. Statistical analysis showed that an increase in IL-1β, IL-6 and a decrease in RANTES were associated with disease severity.Conclusions
This is the first comprehensive report on the production of cytokines, chemokines, and growth factors during acute Chikungunya virus infection. Using these biomarkers, we were able to distinguish between mild disease and more severe forms of Chikungunya fever, thus enabling the identification of patients with poor prognosis and monitoring of the disease. 相似文献44.
Huiqing Zhan Jan M. Spitsbergen Wei Qing Yi Lian Wu Thomas A. Paul James W. Casey Guor Muor Her Zhiyuan Gong 《Marine biotechnology (New York, N.Y.)》2010,12(6):640-649
A retrovirus homologue gene of cellular cyclin D
1
, walleye dermal sarcoma virus rv-cyclin gene (orf A or rv-cyclin), was expressed in the livers of zebrafish under the control of liver fatty acid-binding protein (lfabp) promoter. To prevent possible fatality caused by overexpression of the oncogene, the GAL4/upstream activation sequence (GAL4/UAS)
system was used to maintain the transgenic lines. Thus, both GAL4-activator [Tg(lfabp:GAL4)] and UAS-effector [Tg(UAS:rvcyclin)] lines were generated, and the rv-cyclin gene was activated in the liver after crossing these two lines. Since no obvious neoplasia phenotypes were observed in the
double-transgenic line, cancer susceptibility of the transgenic fish expressing rv-cyclin was tested by carcinogen treatment. Unexpectedly, transgenic fish expressing rv-cyclin gene (rvcyclin+) were more resistant to the carcinogen than siblings not expressing this gene (rvcyclin–). Lower incidences
of multiple and malignant liver tumors were observed in rvcyclin+ than in rvcyclin– fish, and the liver tumors in the rvcyclin+
group appeared later and were less malignant. These results suggest that expression of rv-cyclin protects the fish liver from carcinogen damage and delays onset of malignancy. These findings indicate that transgenic fish
models are powerful systems for investigating mechanisms of inhibition and regression of liver tumors. 相似文献
45.
Chien-Li Chiu Jen-Leih Wu Guor-Mour Her Yi-Li Chou Jiann-Ruey Hong 《Apoptosis : an international journal on programmed cell death》2010,15(6):653-668
Aquatic birnavirus induces post-apoptotic necrotic cell death via a newly synthesized protein-dependent pathway. However,
the involvement of viral genome-encoded protein(s) in this death process remains unknown. In the present study, we demonstrated
that the submajor capsid protein, VP3, up-regulates the pro-apoptotic protein, Bad, in fish and mouse cells. Western blot
analysis revealed that VP3 was expressed in CHSE-214 cells at 4 h post-infection (pi), indicating an early role during viral replication. We cloned
the VP3 gene and tested its function in fish and mouse cells; VP3 overexpression induced apoptotic cell death by TUNEL assay. In
addition, it up-regulated Bad gene expression in zebrafish ZLE cells by threefold at 12 h post-transfection (pt) and in mouse NIH3T3 cells by tenfold at
24 h pt. VP3 up-regulation of Bad expression altered mitochondria function, inducing mitochondrial membrane potential (MMP)
loss and activating initiator caspase-9 and effector caspase-3. Furthermore, reduced Bad expression (65% reduction), MMP loss
(up to 40%), and enhanced cell viability (up to 60%) upon expression of VP3 antisense RNA in CHSE-214 cells at 24 h post-IPNV
infection was observed. Finally, overexpression of the anti-apoptotic gene, zfBcl-xL, reduced VP3-induced apoptotic cell death and caspase-3 activation at 24 h in fish cells. Taken together, these results suggest
that aquatic birnavirus VP3 induces apoptosis via up-regulation of Bad expression and mitochondrial disruption, which activates a downstream caspase-3-mediated death pathway that is blocked by
zfBcl-xL. 相似文献
46.
Yoo KY Yoo DY Hwang IK Park JH Lee CH Choi JH Kwon SH Her S Lee YL Won MH 《Neurochemical research》2011,36(12):2417-2426
Innate immune system is very important to modulate the host defense against a large variety of pathogens. Toll-like receptors
(TLRs) play a key role in controlling innate immune response. Among TLRs, TLR4 is a specific receptor for lipopolysaccharide
and associated with the release of pro-inflammatory cytokines. In the present study, we investigated ischemia-related changes
of TLR4 immunoreactivity and its protein level, and nuclear factor κB (NF-κB) p65 immunoreactivity regarding inflammatory
responses in the hippocampal CA1 region after 5 min of transient cerebral ischemia to identify the correlation between transient
ischemia and inflammation. In the sham-operated group, TLR4 immunoreactivity was easily detected in pyramidal neurons of the
hippocampal CA1 region (CA1). TLR4 immunoreactivity in pyramidal neurons was distinctively decreased after ischemia/reperfusion
(I/R); instead, based on double immunofluorescence study, TLR4 immunoreactivity was expressed in non-pyramidal neurons and
astrocytes from 2 days postischemia. In addition, TLR4 protein level was lowest at 1 day postischemia and highest 4 days after
I/R. On the other hand, NF-κB p65 immunoreactivity was not detected in the CA1 of the sham-operated group, and NF-κB p65 immunoreactivity
was not observed until 1 day after I/R. However, NF-κB p65 immunoreactivity began to be expressed in astrocytes at 2 days
postischemia, and the immunoreactivity was strong 4 days postischemia. Our results indicate that TLR4 and NF-κB p65 immunoreactivity
are changed in CA1 pyramidal neurons and newly expressed in astrocytes, not in microglia, in the CA1 region after transient
cerebral ischemia. 相似文献
47.
48.
Mayara Costa Mansur Tavares Jamilly Lopes de Macêdo Sérgio Ferreira de Lima Júnior Sandra de Andrade Heráclio Melânia Maria Ramos Amorim Maria de Mascena Diniz Maia Paulo Roberto Eleutério de Souza 《Molecular biology reports》2014,41(2):865-874
Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted disease. High-risk human papillomavirus (HR-HPV) is considered the main etiological agent for cervical neoplasia. Evidences showed that the presence of co-infection of CT and HR-HPV plays a central role in the etiology of cervical intraepithelial neoplasia (CIN) and cervical cancer. The goals of this study were: evaluate the human papillomavirus (HPV) and CT prevalence among Brazilian women with abnormal cytology and provide the effect of this association on the severity of cervical neoplasia. The population of this study was composed by 142 women with incident histological incidence of CIN grades I, II, III or cervical cancer from Recife, Northeast of Brazil. The polymerase chain reaction method on a cervical brush specimen was used to detect both agents and the automatic sequencing method was used for HPV genotyping assay. The prevalence of HPV and CT was 100 and 24.65 %, respectively. Thirteen types of HPV were detected; HPV 16, 18, 31 and 33 were the most common. The most prevalent HPV types were HPV 16 and 18. A significant association between CT positive and HPV 16 infection was found (p < 0.0106; OR = 5.31; 95 % IC 1.59–17.67). In the study population, there was diversity of HPV infections, with high-risk types being the most common. Also, the data collected suggest that CT infection may play an important role in the natural history of HPV infection. 相似文献
49.
50.
Seong Chul Hong Kyu-Hee Her Heung-Up Kim Jaechun Lee Sang Pyo Lee Young-Bae Chung 《The Korean journal of parasitology》2014,52(1):117-120
Several studies have reported that the citrus red mites Panonychus citri were an important allergen of citrus-cultivating farmers in Jeju Island. The aim of the present study was to purify and assess properties of a cysteine protease from the mites acting as a potentially pathogenic factor to citrus-cultivating farmers. A cysteine protease was purified using column chromatography of Mono Q anion exchanger and Superdex 200 HR gel filtration. It was estimated to be 46 kDa by gel filtration column chromatography and consisted of 2 polypeptides, at least. Cysteine protease inhibitors, such as trans poxy-succinyl-L-leucyl-amido (4-guanidino) butane (E-64) and iodoacetic acid (IAA) totally inhibited the enzyme activities, whereas serine or metalloprotease inhibitors did not affect the activities. In addition, the purified enzyme degraded human IgG, collagen, and fibronectin, but not egg albumin. From these results, the cysteine protease of the mites might be involved in the pathogenesis such as tissue destruction and penetration instead of nutrient digestion. 相似文献