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611.
Following the ban in 2003 on the use of tributyl-tin compounds in antifouling coatings, the search for an environmentally-friendly alternative has accelerated. Biocidal TBT alternatives, such as diuron and Irgarol 1051®,1 have proved to be environmentally damaging to marine organisms. The issue regarding the use of biocides is that concerning the half-life of the compounds which allow a perpetuation of the toxic effects into the marine food chain, and initiate changes in the early stages of the organisms' life-cycle. In addition, the break-down of biocides can result in metabolites with greater toxicity and longevity than the parent compound. 相似文献
612.
The Gray Wolf is a wide ranging carnivore in Iran, absent only in the central deserts and Dasht-e Lut. This study was carried out to verify whether, despite their high mobility, individual wolves belonging to different populations show morphological variations in the skull. We collected 48 skulls from various regions of Iran and measured 24 variables on the cranium. These primary variables were then used to generate six indices to examine any variations in the shape of the skulls collected in different regions of the country. Although the largest skulls collected for this study originated in the mountainous regions of the northwest, northeast, and west, principle component analysis (PCA) did not result in a meaningful difference in the size and shape of wolf skulls in different regions of Iran. Our results confirm that the minor morphological variations of the skull in wolves of Iran are not an evidence for the separation of wolf populations in different regions or the existence of various subspecies in the country. This uniformity can be explained by the strong gene flow among populations as well as high mobility of the wolf that facilitates movement of individuals between populations. 相似文献
613.
Roxane M. Pommier Rami Jaafar Chang X. Zhang Laurent Bartholin Philippe Bertolino 《Genesis (New York, N.Y. : 2000)》2013,51(2):120-127
Alk4 is a type I receptor that belongs to the transforming growth factor‐beta (TGF‐β) family. It takes part in the signaling of TGF‐β ligands such as Activins, Gdfs, and Nodal that had been demonstrated to participate in numerous mechanisms ranging from early embryonic development to adult‐tissue homeostasis. Evidences indicate that Alk4 is a key regulator of many embryonic processes, but little is known about its signaling in adult tissues and in pathological conditions where Alk4 mutations had been reported. Conventional deletion of Alk4 gene (Acvr1b) results in early embryonic lethality prior gastrulation, which has precluded study of Alk4 functions in postnatal and adult mice. To circumvent this problem, we have generated a conditional Acvr1b floxed‐allele by flanking the fifth and sixth exons of the Acvr1b gene with loxP sites. Cre‐mediated deletion of the floxed allele generates a deleted allele, which behaves as an Acvr1b null allele leading to embryonic lethality in homozygous mutant animals. A tamoxifen‐inducible approach to target disruption of Acvr1b specifically in adult tissues was used and proved to be efficient for studying Alk4 functions in various organs. We report, therefore, a novel conditional model allowing investigation of biological role played by Alk4 in a variety of tissue‐specific contexts. genesis 51:120–127, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
614.
Molecular Biology Reports - Azotobacter chroococcum and A. salinestris do not possess significant and distinct morphological and physiological differences and are often mistaken with each other in... 相似文献
615.
Klančnik Anja Šimunović Katarina Sterniša Meta Ramić Dina Smole Možina Sonja Bucar Franz 《Phytochemistry Reviews》2021,20(1):55-84
Phytochemistry Reviews - Biofilms provide a protective environment for pathogens such as Campylobacter jejuni, the most prevalent foodborne pathogen, and biofilm formation can enhance bacterial... 相似文献
616.
Massarwa Eyass Aronis Ze’ev Eliasy Rami Einav Shmuel Haj-Ali Rami 《Biomechanics and modeling in mechanobiology》2021,20(5):1889-1901
Biomechanics and Modeling in Mechanobiology - A unique three-dimensional (3D) computational multiscale modeling approach is proposed to investigate the influence of presence of microcalcification... 相似文献
617.
Mojdeh Khosravi Hanieh Mohammad Rahimi Abdoreza Nazari Kaveh Baghaei Hamid Asadzadeh Aghdaei Shabnam Shahrokh Meysam Sharifdini Ana Claudia Torrecilhas Fatemeh Mehryab Hamed Mirjalali Faezeh Shekari Mohammad Reza Zali 《Journal of cellular and molecular medicine》2023,27(17):2614-2625
Hydatidosis is a disease caused by the larval stage of Echinococcus granulosus, which involves several organs of intermediate hosts. Evidence suggests a communication between hydatid cyst (HC) and hosts via extracellular vesicles. However, a little is known about the communication between EVs derived from HC fluid (HCF) and host cells. In the current study, EVs were isolated using differential centrifugation from sheep HCF and characterized by western blot, electron microscope and size distribution analysis. The uptake of EVs by human monocyte cell line (THP-1) was evaluated. The effects of EVs on the expression levels of pro- and anti-inflammatory cytokines were investigated using quantitative real-time PCR (RT-PCR), 3 and 24 h after incubation. Moreover, the cytokine level of IL-10 was evaluated in supernatant of THP-1 cell line at 3 and 24 h. EVs were successfully isolated and showed spherical shape with size distribution at 130.6 nm. After 3 h, the expression levels of pro-inflammatory cytokine genes (IL1Β, IL15 and IL8) were upregulated, while after 24 h, the expression levels of pro-inflammatory cytokines were decreased and IL13 gene expression showed upregulation. A statistically significant increase was seen in the levels of IL-10 after 24 h. The main mechanism of the communication between EVs derived from HCF and their host remains unclear; however, time-dependent anti-inflammatory effects in our study suggest that HC may modulate the immune responses via EVs. 相似文献
618.
619.
Ramião Nilza G. Martins Pedro S. Rynkevic Rita Fernandes António A. Barroso Maria Santos Diana C. 《Biomechanics and modeling in mechanobiology》2016,15(5):1307-1323
Biomechanics and Modeling in Mechanobiology - This paper reviews the existing literature on the tests used to determine the mechanical properties of women breast tissues (fat, glandular and tumour... 相似文献
620.
Magdalena C Liebl Jutta Moehlenbrink Huong Becker Günter Raddatz Suhaib
K Abdeen Rami I Aqeilan Frank Lyko Thomas G Hofmann 《Nucleic acids research》2021,49(5):2759
The DNA damage-responsive tumor suppressors p53 and HIPK2 are well established regulators of cell fate decision-making and regulate the cellular sensitivity to DNA-damaging drugs. Here, we identify Deleted in Azoospermia-associated protein 2 (DAZAP2), a small adaptor protein, as a novel regulator of HIPK2 and specifier of the DNA damage-induced p53 response. Knock-down or genetic deletion of DAZAP2 strongly potentiates cancer cell chemosensitivity both in cells and in vivo using a mouse tumour xenograft model. In unstressed cells, DAZAP2 stimulates HIPK2 polyubiquitination and degradation through interplay with the ubiquitin ligase SIAH1. Upon DNA damage, HIPK2 site-specifically phosphorylates DAZAP2, which terminates its HIPK2-degrading function and triggers its re-localization to the cell nucleus. Interestingly, nuclear DAZAP2 interacts with p53 and specifies target gene expression through modulating a defined subset of p53 target genes. Furthermore, our results suggest that DAZAP2 co-occupies p53 response elements to specify target gene expression. Collectively, our findings propose DAZAP2 as novel regulator of the DNA damage-induced p53 response that controls cancer cell chemosensitivity. 相似文献