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71.
72.
Sex-sorting damages spermatozoa function, shortening their lifespan and fertility. This study used an immunofluorescence technique to investigate the effect of sex-sorting on the localization of glucose transporters (GLUTs) in boar spermatozoa. GLUTs are trans-membrane proteins responsible for glucose transport within cells. Distribution of GLUTs on sperm cells was similar in unsorted and sex-sorted semen, suggesting that the flow cytometric sex-sorting process did not affect the sperm energy apparatus.  相似文献   
73.
DNA double-strand breaks (DSBs) are highly hazardous for genome integrity because they have the potential to cause mutations, chromosomal rearrangements and genomic instability. The cellular response to DSBs is orchestrated by signal transduction pathways, known as DNA damage checkpoints, which are conserved from yeasts to humans. These pathways can sense DNA damage and transduce this information to specific cellular targets, which in turn regulate cell cycle transitions and DNA repair. The mammalian protein kinases ATM and ATR, as well as their budding yeast corresponding orthologs Tel1 and Mec1, act as master regulators of the checkpoint response to DSBs. Here, we review the early steps of DSB processing and the role of DNA-end structures in activating ATM/Tel1 and ATR/Mec1 in an orderly and reciprocal manner.  相似文献   
74.
Combinatorial peptide ligand libraries (CPLLs) have been adopted for investigating the proteomes of lemon peels and pulp, of a home-made alcoholic infusion of peels and of a very popular Italian liqueur called “Limoncello”, stated to be an infusion of the flavedo (the outer, yellow skin of lemons). The aim of this study was not only to perform the deepest investigation so far of the lemon peel proteome but also to assess the genuineness of the commercial liqueur via a three-pronged attack. First, different extraction techniques have been used for the characterization of the peel (and additionally of the pulp) proteome, secondly a home-made infusion has been analysed and finally the proteome of the commercial drink was checked. The peel (the flavedo, not the underlying layer called albedo) proteome has been evaluated via prior capture with CPLLs at different pH values (2.2 and 7.2). Via mass spectrometry analysis of the recovered fractions, after elution of the captured populations in 4% boiling SDS, we could identify a total of 1011 unique gene products in the peel extracts and 674 in the pulp, 264 proteins in the home-made infusion and just 8 proteins (and protein fragments), together with 12 peptides, in one Italian Limoncello produced in the Sorrento Region, thus proving the genuineness of this product. On the contrary, cheaper Limoncellos were devoid of any protein/peptide, casting doubts on their production from vegetable extracts. This could be the starting point for investigating the genuineness and natural origin of commercial drinks in order to protect consumers from adulterated products.  相似文献   
75.
The main goal of the work was to uncover the dynamical changes in actin induced by the binding of cofilin and profilin. The change in the structure and flexibility of the small domain and its function in the thermodynamic stability of the actin monomer were examined with fluorescence spectroscopy and differential scanning calorimetry (DSC). The structure around the C-terminus of actin is slightly affected by the presence of cofilin and profilin. Temperature dependent fluorescence resonance energy transfer measurements indicated that both actin binding proteins decreased the flexibility of the protein matrix between the subdomains 1 and 2. Time resolved anisotropy decay measurements supported the idea that cofilin and profilin changed similarly the dynamics around the fluorescently labeled Cys-374 and Lys-61 residues in subdomains 1 and 2, respectively. DSC experiments indicated that the thermodynamic stability of actin increased by cofilin and decreased in the presence of profilin. Based on the information obtained it is possible to conclude that while the small domain of actin acts uniformly in the presence of cofilin and profilin the overall stability of actin changes differently in the presence of the studied actin binding proteins. The results support the idea that the small domain of actin behaves as a rigid unit during the opening and closing of the nucleotide binding pocket in the presence of profilin and cofilin as well. The structural arrangement of the nucleotide binding cleft mainly influences the global stability of actin while the dynamics of the different segments can change autonomously.  相似文献   
76.
Genome-wide association studies (GWAS) simultaneously investigating hundreds of thousands of single nucleotide polymorphisms (SNP) have become a powerful tool in the investigation of new disease susceptibility loci. Haplotypes are sometimes thought to be superior to SNPs and are promising in genetic association analyses. The application of genome-wide haplotype analysis, however, is hindered by the complexity of haplotypes themselves and sophistication in computation. We systematically analyzed the haplotype effects for breast cancer risk among 5,761 African American women (3,016 cases and 2,745 controls) using a sliding window approach on the genome-wide scale. Three regions on chromosomes 1, 4 and 18 exhibited moderate haplotype effects. Furthermore, among 21 breast cancer susceptibility loci previously established in European populations, 10p15 and 14q24 are likely to harbor novel haplotype effects. We also proposed a heuristic of determining the significance level and the effective number of independent tests by the permutation analysis on chromosome 22 data. It suggests that the effective number was approximately half of the total (7,794 out of 15,645), thus the half number could serve as a quick reference to evaluating genome-wide significance if a similar sliding window approach of haplotype analysis is adopted in similar populations using similar genotype density.  相似文献   
77.

Objective

To map and investigate the relationships established on the web between leading health-research institutions around the world.

Methods

Sample selection was based on the World Health Organization (WHO) Collaborating Centres (CCs). Data on the 768 active CCs in 89 countries were retrieved from the WHO''s database. The final sample consisted of 190 institutions devoted to health sciences in 42 countries. Data on each institution''s website were retrieved using webometric techniques (interlinking), and an asymmetric matrix was generated for social network analysis.

Findings

The results showed that American and European institutions, such as the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH) and the National Institute of Health and Medical Research (INSERM), are the most highly connected on the web and have a higher capacity to attract hyperlinks. The Karolinska Institute (KI-SE) in Sweden is well placed as an articulation point between several integrants of the network and the component''s core but lacks general recognition on the web by hyperlinks. Regarding the north-south divide, Mexico and Brazil appear to be key southern players on the web. The results showed that the hyperlinks exchanged between northern and southern countries present an abysmal gap: 99.49% of the hyperlinks provided by the North are directed toward the North itself, in contrast to 0.51% that are directed toward the South. Regarding the South, its institutions are more connected to its northern partners, with 98.46% of its hyperlinks directed toward the North, and mainly toward the United States, compared with 1.54% toward southern neighbors.

Conclusion

It is advisable to strengthen integration policies on the web and to increase web networking through hyperlink exchange. In this way, the web could actually reflect international cooperation in health and help to legitimize and enhance the visibility of the many existing south-south collaboration networks.  相似文献   
78.
Increasing evidence supports the involvement of autophagy in the etiopathology of autoimmune diseases. Despite the identification of autophagy-related protein (Atg)-5 as one of the susceptibility loci in systemic Lupus erythematosus (SLE), the consequences of the carriage of these mutations for patients remain unclear. The present work analyzed the association of Atg5 rs573775 single nucleotide polymorphism (SNP) with SLE susceptibility, IFNα, TNFα and IL-10 serum levels, and clinical features, in 115 patients and 170 healthy individuals. Patients who where carriers of the rs573775 T* minor allele presented lower IFNα levels than those with the wild genotype, whereas the opposite result was detected for IL-10. Thus, since IL-10 production was regulated by rs1800896 polymorphisms, we evaluated the effect of this Atg5 mutation in genetically high and low IL-10 producers. Interestingly, we found that the rs573775 T* allele was a risk factor for SLE in carriers of the high IL-10 producer genotype, but not among genetically low producers. Moreover, IL-10 genotype influences SLE features in patients presenting the Atg5 mutated allele. Specifically, carriage of the rs573775 T* allele led to IL-10 upregulation, reduced IFNα and TNFα production and a low frequency of cytopenia in patients with the high IL-10 producer genotype, whereas patients with the same Atg5 allele that were low IL-10 producers presented reduced amounts of all these cytokines, had a lower prevalence of anti-dsDNA antibodies and the latest onset age. In conclusion, the Atg5 rs573775 T* allele seems to influence SLE susceptibility, cytokine production and disease features depending on other factors such as functional IL-10 genotype.  相似文献   
79.
Many invasive species exploit the disturbed habitats created by human activities. Understanding the effects of habitat disturbance on invasion success, and how disturbance interacts with other factors (such as biotic resistance to the invaders from the native fauna) may suggest new ways to reduce invader viability. In tropical Australia, commercial livestock production can facilitate invasion by the cane toad (Rhinella marina), because hoofprints left by cattle and horses around waterbody margins provide distinctive (cool, moist) microhabitats; nevertheless the same microhabitat can inhibit the success of cane toads by increasing the risks of predation or drowning. Metamorph cane toads actively select hoofprints as retreat-sites to escape dangerous thermal and hydric conditions in the surrounding landscape. However, hoofprint geometry is important: in hoofprints with steep sides the young toads are more likely to be attacked by predatory ants (Iridomyrmex reburrus) and are more likely to drown following heavy rain. Thus, anthropogenic changes to the landscape interact with predation by native taxa to affect the ability of cane toads in this vulnerable life-history stage to thrive in the harsh abiotic conditions of tropical Australia.  相似文献   
80.
This study describes the age structure and sex-specific growth patterns of Lahille's bottlenose dolphins (Tursiops truncatus gephyreus), a subspecies endemic to the Southwest Atlantic Ocean (SWAO). The ages of 120 animals collected in southern Brazil between 1976 and 2017 were determined. We found high frequencies of young animals, mostly males, with no sex bias among adults. A temporal change in the age structure of strandings was observed, and we conclude it is a consequence of increased bycatch rates of young dolphins after 2000. The oldest male and female were 27 and 44 years old, respectively, suggesting that females live longer than males in southern Brazil. Growth curve analysis using Gompertz and Laird-Gompertz growth models estimated asymptotic lengths of 316.5 cm for females and 351.6 cm for males, (reached around 13 and 18 years old, respectively), supporting sexual size dimorphism for the subspecies. A second growth pulse was identified for males. Our work highlights the benefit of long-term studies and contributes valuable information toward understanding the life history of Lahille's bottlenose dolphin. It will serve as baseline for future studies that seek to understand mortality patterns of bottlenose dolphins elsewhere and the effects of anthropogenic actions on the survival of these animals.  相似文献   
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