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11.
Gonzalez E Kulkarni H Bolivar H Mangano A Sanchez R Catano G Nibbs RJ Freedman BI Quinones MP Bamshad MJ Murthy KK Rovin BH Bradley W Clark RA Anderson SA O'connell RJ Agan BK Ahuja SS Bologna R Sen L Dolan MJ Ahuja SK 《Science (New York, N.Y.)》2005,307(5714):1434-1440
Segmental duplications in the human genome are selectively enriched for genes involved in immunity, although the phenotypic consequences for host defense are unknown. We show that there are significant interindividual and interpopulation differences in the copy number of a segmental duplication encompassing the gene encoding CCL3L1 (MIP-1alphaP), a potent human immunodeficiency virus-1 (HIV-1)-suppressive chemokine and ligand for the HIV coreceptor CCR5. Possession of a CCL3L1 copy number lower than the population average is associated with markedly enhanced HIV/acquired immunodeficiency syndrome (AIDS) susceptibility. This susceptibility is even greater in individuals who also possess disease-accelerating CCR5 genotypes. This relationship between CCL3L1 dose and altered HIV/AIDS susceptibility points to a central role for CCL3L1 in HIV/AIDS pathogenesis and indicates that differences in the dose of immune response genes may constitute a genetic basis for variable responses to infectious diseases. 相似文献
12.
Carol L. Chambers Samuel A. Cushman Arnulfo Medina-Fitoria José Martínez-Fonseca Marlon Chávez-Velásquez 《Landscape Ecology》2016,31(6):1299-1318
Context
Scale dependence of bat habitat selection is poorly known with few studies evaluating relationships among landscape metrics such as class versus landscape, or metrics that measure composition or configuration. This knowledge can inform conservation approaches to mitigate habitat loss and fragmentation.Objectives
We evaluated scale dependence of habitat associations and scaling patterns of landscape metrics in relation to bat occurrence or capture rate in forests of southwestern Nicaragua.Methods
We captured 1537 bats at 35 locations and measured landscape and class metrics across 10 spatial scales (100–1000 m) surrounding capture locations. We conducted univariate scaling across the 10 scales and identified scales and variables most related to bat occurrence or capture rate.Results
Edge and patch density, at both landscape and class levels, were the most important variables across species. Feeding guilds varied in their response to metrics. Certain landscape and configuration metrics were most influential at fine (100 m) and/or broad (1000 m) spatial scales while most class and composition metrics were influential at intermediate scales.Conclusions
These results provide insight into the scale dependence of habitat associations of bat species and the influence of fine and broad scales on habitat associations. The effects of scale, examined in our study and others from fine (100 m) to broad (5 km) indicate habitat relationships for bats may be more informative at larger scales. Our results suggest there could be general differences in scale relationships for different groups of landscape metrics, which deserves further evaluation in other taxonomic groups.13.
Use of controlled internal drug releasing (CIDR) devices to control reproduction in goats: A review 
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下载免费PDF全文 High reproductive rates are necessary in order to increase the productivity of goat operations. Progesterone and its analogues are widely used in other species to control the reproductive system to facilitate synchronized births, induce fertile estrus or to facilitate the use of assisted reproductive techniques with the goal of increasing productivity of livestock. Progesterone impregnated controlled internal drug releasing (CIDR) devices are approved for delivery of the natural hormone progesterone to synchronize and induce fertile estrus in sheep. A few studies have reported a high estrous response and pregnancy rates when CIDRs are used to induce estrus in goats. However, significant variation exists in the duration of treatment (5‐16 days) and in the use of exogenous gonadotropins as part of the treatment protocol. As gonadotropins are not currently approved for commercial use in small ruminants in the USA, studies are needed to determine the necessity for exogenous gonadotropins and whether they can be replaced by enhancing endogenous secretion through photoperiodic manipulation of the doe and \ or increase stimulation through the ‘buck‐effect’. Future studies must not only evaluate efficacy, but should consider the economic feasibility of using CIDRs in commercial production systems. 相似文献
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Marlon Felipe Higuita Palacio Olga I Montoya Clara I Saldamando Erika García-Bonilla Howard Junca Gloria E Cadavid-Restrepo Claudia Ximena Moreno-Herrera 《Journal of insect science (Online)》2021,21(6)
Spodoptera frugiperda is a polyphagous pest of several crops of economic importance. Nowadays, the insect is broadly distributed in America and, recently, in Africa, Asia, and Australia. The species has diverged into corn and rice strains. The role of the gut microbiota in insect physiology is relevant due to its participation in crucial functions. However, knowledge of seasonal variations that alter the gut microbiome in pests is limited. Gut microbiome composition between the dry and rainy seasons was analyzed with cultured and uncultured approaches in S. frugiperda corn strain larvae collected at Northwest Colombia, as seasonal microbiome changes might fluctuate due to environmental changes. On the basis of culture-dependent methods, results show well-defined microbiota with bacterial isolates belonging to Enterococcus, Klebsiella (Enterobacteriales: Enterobacteriaceae), Enterobacter (Enterobacterales: Enterobacteriaceae), and Bacillus (Bacillales: Bacillaceae) genera. The community composition displayed a low bacterial diversity across all samples. The core community detected with uncultured methods was composed of Enterococcus, Erysipelatoclostridium (Erysipelotrichales: Erysipelotrichaceae), Rasltonia (Burkholderiales: Burkholderiaceae), and Rhizobium (Hyphomicrobiales: Rhizobiaceae) genera, and Enterobacteriaceae family members. Significant differences in microbiome diversity were observed between the two seasons. The relative abundance of Erysipelatoclostridium was high in the dry season, while in the phylotype ZOR0006 (Erysipelotrichales: Erysipelotrichaceae) and Tyzzerella (Lachnospirales: Lachnospiraceae) genus, the relative abundance was high in the rainy season. The overall low gut bacterial diversity observed in the S. frugiperda corn strain suggests a strong presence of antagonist activity as a selection factor possibly arising from the host, the dominant bacterial types, or the material ingested. Targeting the stability and predominance of this core microbiome could be an additional alternative to pest control strategies, particularly in this moth. 相似文献
16.
Lucas Rafael de Souza Camacho Marlon Mathias Dacal Coan Carlos Alberto Scapim Ronald Jos Barth Pinto Dauri Jos Tessmann Rodrigo Ivn Contreras‐Soto 《Plant Breeding》2019,138(6):770-780
Southern corn rust (SCR) is a fungal disease found on corn in several countries worldwide. In Brazil, the disease can result in productivity losses of 65%, especially in areas with a history of the disease. In this study, the genetic architecture and identification of genomic regions associated with SCR resistance was investigated by performing a genome‐wide association study. Genotyping‐by‐sequencing was performed to carry out the association between single nucleotide polymorphism (SNP) markers and phenotypic data from two environments on a panel of 164 maize inbred lines. Eight SNPs were identified as significant for SCR resistance. These SNPs were colocalized with QTL regions, some of which underlie candidate resistance genes with functions that play an important role in the stress response during pathogen recognition. These candidate genes, involved in plant defense pathways, could be associated with partial resistance to SCR and provide a partial comprehensive insight into the genetic architecture of this trait. After validation of the SNPs, they will be useful for marker–assisted selection and for a better understanding of maize resistance to SCR. 相似文献
17.
The present study examined the effect of transportation stress on hypothalamic–pituitary–adrenal axis responsiveness to tropic hormone stimulation and on abundance of corticotropin releasing factor (CRF) receptor R1 (CRFR1) and arginine vasopressin (AVP) receptor V3 (V3) mRNAs in the anterior pituitary (AP) of cattle. Holstein steers were transported for 10 h or used as non-transported controls (NTC). Blood samples were collected at start of transportation and every 1–2 h thereafter. To test AP responsiveness to tropic hormones, animals were challenged (i.v.) with CRF (0.5 μg/kg), AVP (1 μg/kg) or CRF plus AVP immediately after end of transportation and blood samples collected every 30 min for 3 h. The AP of animals transported for 0, 4 or 10 h were harvested for mRNA analyses. Plasma ACTH in transported animals increased within 1 h and remained elevated for 6 and 8 h versus NTC and 0 h values, respectively. Plasma concentrations of cortisol increased in response to transportation and remained elevated throughout the transport period. Injection of CRF or AVP to NTC animals increased plasma ACTH, but ACTH secretion in response to CRF or AVP was dramatically reduced in transported animals. ACTH secretion following co-injection of CRF and AVP tended to be less in transported animals, but was almost 100% greater than when secretagogues were administered separately. Despite decreased AP responsiveness to CRF and AVP, AP CRFR1 and V3 mRNAs were increased after 10 h transportation. Results indicate decreased AP responsiveness to CRF and AVP may regulate duration of ACTH secretion in response to transportation stress in cattle. 相似文献
18.
Kobayashi Y Okuda H Nakamura K Sato G Itou T Carvalho AA Silva MV Mota CS Ito FH Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(11):1145-1154
To investigate the genetic characteristics of phosphoprotein (P) and matrix protein (M) genes of variable rabies virus (RV) prevalent in Brazil, the authors genetically characterized the P and M genes from 30 Brazilian RV field isolates. Phylogenetic analysis based on the P and M genes revealed the presence of six RV variants that consisted primarily of three insectivorous bats, the vampire bat, dog and fox in Brazil. Specific amino acid substitutions corresponding to these phylogenetic lineages were observed, with Asp(42) and Glu(62) in the P protein found to be characteristic of Brazilian chiroptera- and carnivora-related RVs, respectively. Amino acid sequence motifs predicted to associate with a viral function in the P and M proteins were conserved among Brazilian RV variants. 相似文献
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Donald A. Croll Heidi Dewar Nicholas K. Dulvy Daniel Fernando Malcolm P. Francis Felipe Galván‐Magaña Martin Hall Shawn Heinrichs Andrea Marshall Douglas Mccauley Kelly M. Newton Giuseppe Notarbartolo‐Di‐Sciara Mary O'Malley John O'Sullivan Marloes Poortvliet Marlon Roman Guy Stevens Bernie R. Tershy William T. White 《水产资源保护:海洋与淡水生态系统》2016,26(3):562-575
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20.
Marlon Ferrari Wanessa Aparecida Carlos da Silva Rafael Veríssimo Monteiro 《Journal of Exotic Pet Medicine》2013,22(4):393-395
Nine healthy chinchillas (Chinchilla lanigera) were used to characterize the ultrasonographic size and anatomical structure of the kidneys. Sonographic evaluations were performed with the aid of a 12-MHz linear probe. Kidney measurements included total width and length, total organ area, cortex and medullary thickness, and width and length of the renal pelvis. Based on the results of this study, normal chinchilla kidneys are located retroperitoneally, with the right kidney in a more cranial location than the left. Statistical analysis showed that measurements were similar between contralateral kidneys and between sexes. Chinchilla kidneys have a single papilla and a wider renal pelvis compared with the renal pelvis of dogs and cats. Moreover, chinchilla kidneys have a longer medullary area. The data herein may aid diagnosis of renal disease in chinchillas, avoiding misinterpretations of ultrasonic findings involving the kidneys of this species. 相似文献