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991.
Selection of critical habitats for bottlenose dolphins (Tursiops truncatus) based on behavioral data,in relation to marine traffic in the Istanbul Strait,Turkey 下载免费PDF全文
Marine traffic is a significant source of disturbance to the bottlenose dolphin population in the Istanbul Strait, Turkey. To determine the importance of this threat, behavioral data together with sighting data of both dolphins and marine vessels were assessed for 2012. The current study suggests that the Istanbul Strait is used mostly as a foraging ground for bottlenose dolphins. Nonetheless, in the same area there is intense marine traffic as well as increase of industrial fishing activities in autumn. The findings of this study indicated that high‐speed ferries and high‐speed boats were the most significant source of disturbance. Moreover, increased densities of fishing vessels resulted in a drastic decline of dolphin sightings. This study highlights that vessel type, speed, distance, and density have a cumulative negative effect on dolphins. In order to mitigate the impacts of vessels, it is necessary to establish managed areas in the Istanbul Strait. Such proposed areas should limit speed and density of marine traffic and have specific restrictions on vessel routes. We propose three different seasonal managed areas according to their values as critical habitat for bottlenose dolphins in the strait. 相似文献
992.
Amandine Hauer Krystel De Cruz Thierry Cochard Sylvain Godreuil Claudine Karoui Sylvie Henault Tabatha Bulach Anne-Laure Ba?uls Franck Biet María Laura Boschiroli 《PloS one》2015,10(2)
To study the dynamics of bovine tuberculosis (bTB) in France, 4,654 M. bovis strains isolated mainly from livestock and wildlife since 1978 were characterized by spoligotyping and MLVA based on MIRU-VNTR. In our study spoligotyping allowed the discrimination of 176 types although 3 spoligotypes are predominant and account for more than half of the total strain population: SB0120 (26%), SB0134 (11%) and SB0121 (6%). In addition, 11% of the isolates, principally from Southern France, showing close spoligotypes and MIRU-VNTR types have been gathered in a family designated as the “F4-family”. MLVA typing allowed extensive discrimination, particularly for strains with predominant spoligotypes, with a total of 498 genotypes, several of which were highly regionalized. The similarity of the strains’ genetic relationships based on spoligotyping and MIRU-VNTR markers supports the co-existence of different clonal populations within the French M. bovis population. A genetic evolution of the strains was observed both geographically and in time. Indeed, as a result of the reduction of bTB due to the national control campaigns, a large reduction of the strains’ genetic variability took place in the last ten years. However, in the regions were bTB is highly prevalent at present, cases in both livestock and in wildlife are due to the spread of unique local genotype profiles. Our results show that the highly discriminating genotyping tools used in this study for molecular studies of bTB are useful for addressing pending questions, which would lead to a better insight into the epidemiology of the disease, and for finding proper solutions for its sustainable control in France. 相似文献
993.
Soon Chul Heo Won Chul Shin Mi Jeong Lee Ba Reun Kim Il Ho Jang Eun-Jung Choi Jung Sub Lee Jae Ho Kim 《PloS one》2015,10(3)
Background
Periostin, an extracellular matrix protein, is expressed in bone, more specifically, the periosteum and periodontal ligaments, and plays a key role in formation and metabolism of bone tissues. Human adipose tissue-derived mesenchymal stem cells (hASCs) have been reported to differentiate into osteoblasts and stimulate bone repair. However, the role of periostin in hASC-mediated bone healing has not been clarified. In the current study, we examined the effect of periostin on bone healing capacity of hASCs in a critical size calvarial defect model.Methods and Results
Recombinant periostin protein stimulated migration, adhesion, and proliferation of hASCs in vitro. Implantation of either hASCs or periostin resulted in slight, but not significant, stimulation of bone healing, whereas co-implantation of hASCs together with periostin further potentiated bone healing. In addition, the number of Ki67-positive proliferating cells was significantly increased in calvarial defects by co-implantation of both hASCs and periostin. Consistently, proliferation of administered hASCs was stimulated by co-implantation with periostin in vivo. In addition, co-delivery of hASCs with periostin resulted in markedly increased numbers of CD31-positive endothelial cells and α-SMA-positive arterioles in calvarial defects.Conclusions
These results suggest that recombinant periostin potentiates hASC-mediated bone healing by stimulating proliferation of transplanted hASCs and angiogenesis in calvarial defects. 相似文献994.
Wei-Jun Gu Qian Zhang Ying-Qian Wang Guo-Qing Yang Tian-Pei Hong Da-Long Zhu Jin-Kui Yang Guang Ning Nan Jin Kang Chen Li Zang An-Ping Wang Jin Du Xian-Ling Wang Li-Juan Yang Jian-Ming Ba Zhao-Hui Lv Jing-Tao Dou Yi-Ming Mu 《Experimental biology and medicine (Maywood, N.J.)》2015,240(11):1480-1489
Kallmann syndrome, a form of idiopathic hypogonadotropic hypogonadism, is characterized by developmental abnormalities of the reproductive system and abnormal olfaction. Despite association of certain genes with idiopathic hypogonadotropic hypogonadism, the genetic inheritance and expression are complex and incompletely known. In the present study, seven Kallmann syndrome pedigrees in an ethnic Han Chinese population were screened for genetic mutations. The exons and intron–exon boundaries of 19 idiopathic hypogonadotropic hypogonadism (idiopathic hypogonadotropic hypogonadism)-related genes in seven Chinese Kallmann syndrome pedigrees were sequenced. Detected mutations were also tested in 70 sporadic Kallmann syndrome cases and 200 Chinese healthy controls. In pedigrees 1, 2, and 7, the secondary sex characteristics were poorly developed and the patients’ sense of smell was severely or completely lost. We detected a genetic mutation in five of the seven pedigrees: homozygous KAL1 p.R191ter (pedigree 1); homozygous KAL1 p.C13ter (pedigree 2; a novel mutation); heterozygous FGFR1 p.R250W (pedigree 3); and homozygous PROKR2 p.Y113H (pedigrees 4 and 5). No genetic change of the assayed genes was detected in pedigrees 6 and 7. Among the 70 sporadic cases, we detected one homozygous and one heterozygous PROKR2 p.Y113H mutation. This mutation was also detected heterozygously in 2/200 normal controls and its pathogenicity is likely questionable. The genetics and genotype–phenotype relationships in Kallmann syndrome are complicated. Classical monogenic inheritance does not explain the full range of genetic inheritance of Kallmann syndrome patients. Because of stochastic nature of genetic mutations, exome analyses of Kallmann syndrome patients may provide novel insights. 相似文献
995.
Gerg? Gógl Kyle D. Schneider Brian J. Yeh Nashida Alam Alex N. Nguyen Ba Alan M. Moses Csaba Hetényi Attila Reményi Eric L. Weiss 《PLoS biology》2015,13(5)
Eukaryotic cells commonly use protein kinases in signaling systems that relay information and control a wide range of processes. These enzymes have a fundamentally similar structure, but achieve functional diversity through variable regions that determine how the catalytic core is activated and recruited to phosphorylation targets. “Hippo” pathways are ancient protein kinase signaling systems that control cell proliferation and morphogenesis; the NDR/LATS family protein kinases, which associate with “Mob” coactivator proteins, are central but incompletely understood components of these pathways. Here we describe the crystal structure of budding yeast Cbk1–Mob2, to our knowledge the first of an NDR/LATS kinase–Mob complex. It shows a novel coactivator-organized activation region that may be unique to NDR/LATS kinases, in which a key regulatory motif apparently shifts from an inactive binding mode to an active one upon phosphorylation. We also provide a structural basis for a substrate docking mechanism previously unknown in AGC family kinases, and show that docking interaction provides robustness to Cbk1’s regulation of its two known in vivo substrates. Co-evolution of docking motifs and phosphorylation consensus sites strongly indicates that a protein is an in vivo regulatory target of this hippo pathway, and predicts a new group of high-confidence Cbk1 substrates that function at sites of cytokinesis and cell growth. Moreover, docking peptides arise in unstructured regions of proteins that are probably already kinase substrates, suggesting a broad sequential model for adaptive acquisition of kinase docking in rapidly evolving intrinsically disordered polypeptides. 相似文献
996.
Several genes encoding for different cytokines may play crucial roles in host susceptibility to Brucellosis, since the cytokine production capacity varies among individuals and depends on the cytokine gene polymorphism. The association of the cytokine gene polymorphisms with the development of Brucellosis was investigated in this study. DNA samples were obtained from a Turkish population of 40 patients with Brucellosis, and 50 healthy control subjects. All genotyping (IL-6, IL10, IFN-gamma, TGF-beta and TNF-alpha) experiments were performed using sequence-specific primers PCR (PCR-SSP). When compared to the healthy controls, the frequencies of high/intermediate producing genotypes of IL-10 and high producing genotype of IL-6 were significantly more common in the patient group. These results suggest that IL-10 and IL-6 gene polymorphisms may affect susceptibility to Brucellosis and increase risk of developing the disease. In order to confirm the biological significance of our results, further studies should be performed in larger population groups. 相似文献
997.
Stobadine inhibits doxorubicin-induced apoptosis through a caspase-9 dependent pathway in P815 mastocytoma cells 总被引:3,自引:0,他引:3
Doxorubicin (DOXO), a widely used chemotherapeutic agent, induces apoptosis in transformed and non-transformed cells. The apoptotic effect of DOXO has been linked to the generation of reactive oxygen species (ROS). Antioxidants may be effective in the prevention of DOX-induced apoptosis. In the present study we investigated the effects of stobadine, a pyridoindole antioxidant in a DOXO-induced apoptosis model of P815 cells by flow cytometric analyses and by measuring caspase-3 and caspase-9 activities. Pretreating cells with stobadine significantly increased cell viability and decreased apoptosis rate. Inhibition in apoptosis was observed at maximum levels following treatment of cells with 10(-7)M stobadine as evident from flow cytometric analyses. The antiapoptotic effect of stobadine was further confirmed by inhibition of caspase-3 and caspase-9 activities. We found that the antioxidative effects of stobadine were comparable to the effects of a well known antioxidant, N-acetyl l-cysteine (NAC). 相似文献
998.
Yalçin B Tezel GG Arda N Erman M Alli N 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2007,29(6):358-364
OBJECTIVE: To investigate expression patterns and relationship of vascular endothelial growth factor (VEGF), vascular endothelial receptor-3 (VEGF-R3) (FLT-4) and cyclooxygenase-2 (COX-2) in psoriasis. STUDY DESIGN: Forty-three patients were included in this study. The clinical severity of psoriasis was assessed using the psoriasis area and severity index (PASI). Punch biopsy samples both from psoriatic and nonlesional skin were taken and VEGF, VEGF-R3 and COX-2 expressions determined. RESULTS: VEGF, VEGF-R3 and COX-2 expressions were detected in 90.9%, 78.0% and 86.4% of psoriatic and 84.1%, 71.8%, and 84.1% of nonlesional skin, respectively. Epidermal VEGF, VEGF-R3 and COX-2 expressions were detected in 56.8%, 77.8% and 34.1 of psoriatic and 75%, 78.1% and 65.9% of nonlesional skin, respectively. In dermis, VEGF, VEGF-R3 and COX-2 expression was observed in 88.6%, 77.5% and 84.1% of psoriatic and 81.8%, 64.1% and 77.3% of nonlesional skin, respectively. Among the PASI subgroups no statistically significant differences were detected for VEGF, VEGF-R3 and COX-2 expression. CONCLUSION: Our study demonstrated that VEGF, VEGF-R3 and COX-2 expression in psoriatic and nonlesional skin is significantly high in epidermis and dermis. Although there was significant concordance between VEGF and VEGF-R3 expressions in psoriatic lesions, there seems to be no concordance between the others. 相似文献
999.
Riviere T Diedhiou AG Diabate M Senthilarasu G Natarajan K Verbeken A Buyck B Dreyfus B Bena G Ba AM 《Mycorrhiza》2007,17(5):415-428
Ectomycorrhizal (ECM) fungi have a worldwide distribution. However, the ecology of tropical ECM fungi is poorly documented,
limiting our understanding of the symbiotic associations between tropical plants and fungi. ECM Basidiomycete diversity was
investigated for the first time in two tropical rain forests in Africa (Western Upper Guinea) and in Asia (Western Ghats,
India), using a fragment of the mitochondrial large subunit rRNA gene to type 140 sporocarps and 54 ectomycorrhizas. To evaluate
taxonomic diversity, phylogenetic analyses were performed, and 40 sequences included from identified European specimens were
used as taxonomic benchmarks. Five clades were recovered corresponding to six taxonomic groups: boletoids, sclerodermatoids,
russuloids, thelephoroids, and a clade grouping the Amanitaceae and Tricholomataceae families. Our results revealed that the
Russulaceae species display a great diversity with several putative new species, especially in Guinea. Other taxonomic issues
at family/section levels are also briefly discussed. This study provides preliminary insights into taxonomic diversity, ECM
status, and biogeographic patterns of ECM fungi in tropical two rain forest ecosystems, which appear to be as diverse as in
temperate and boreal forests. 相似文献
1000.
Lecain E Omri B Behar-Cohen F Tran Ba Huy P Crisanti P 《Apoptosis : an international journal on programmed cell death》2007,12(2):333-342
Aminoglycoside antibiotics are ototoxic, inducing irreversible sensorineural hearing loss mediated by oxidative and excitotoxic
stresses. The NF-κB pathway is involved in the response to aminoglycoside damage in the cochlea. However, the molecular mechanisms
of this ototoxicity remain unclear. We investigated the expression of PKCζ, a key regulator of NF-κB activation, in response
to aminoglycoside treatment. Amikacin induced PKCζ cleavage and nuclear translocation. These events were concomitant with
chromatin condensation and paralleled the decrease in NF-κB (p65) levels in the nucleus. Amikacin also induced the nuclear
translocation of apoptotic inducing factor (AIF). Prior treatment with aspirin prevented PKCζ cleavage and nuclear translocation.
Thus, aspirin counteracts the early effects of amikacin, thereby protecting hair cells and spiral ganglion neurons. These
results demonstrate that PKCζ acts as sentinel connecting specific survival pathways to mediate cellular responses to amikacin
ototoxicity.
E. Lecain and B. Omri both authors contributed equally. 相似文献