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931.
Andrea Alter Louis de Léséleuc Nguyen Van Thuc Vu Hong Thai Nguyen Thu Huong Nguyen Ngoc Ba Cynthia Chester Cardoso Audrey Virginia Grant Laurent Abel Milton Ozório Moraes Alexandre Alcaïs Erwin Schurr 《Human genetics》2010,127(3):337-348
The chromosomal region 10p13 has been linked to paucibacillary leprosy in two independent studies. The MRC1 gene, encoding the human mannose receptor (MR), is located in the 10p13 region and non-synonymous SNPs in exon 7 of the gene have been suggested as leprosy susceptibility factors. We determined that G396S is the only non-synonymous exon 7-encoded polymorphism in 396 unrelated Vietnamese subjects. This SNP was genotyped in 490 simplex and 90 multiplex leprosy families comprising 704 patients (47% paucibacillary; 53% multibacillary). We observed significant under-transmission of the serine allele of the G396S polymorphism with leprosy per se (P = 0.036) and multibacillary leprosy (P = 0.034). In a sample of 384 Brazilian leprosy cases (51% paucibacillary; 49% multibacillary) and 399 healthy controls, we observed significant association of the glycine allele of the G396S polymorphism with leprosy per se (P = 0.016) and multibacillary leprosy (P = 0.023). In addition, we observed a significant association of exon 7 encoded amino acid haplotypes with leprosy per se (P = 0.012) and multibacillary leprosy (P = 0.004). Next, we tested HEK293 cells over-expressing MR constructs (293-MR) with three exon 7 haplotypes of MRC1 for their ability to bind and internalize ovalbumin and zymosan, two classical MR ligands. No difference in uptake was measured between the variants. In addition, 293-MR failed to bind and internalize viable Mycobacterium leprae and BCG. We propose that the MR–M. leprae interaction is modulated by an accessory host molecule of unknown identity. 相似文献
932.
André Luís Branco de Barros Luciene das Graças Mota Carolina de Aguiar Ferreira Mônica Cristina de Oliveira Alfredo Miranda de Góes Valbert Nascimento Cardoso 《Bioorganic & medicinal chemistry letters》2010,20(21):6182-6184
A bombesin derivative was successfully radiolabeled in high labeling yield. Biodistribution studies and scintigraphic images in Ehrlich tumor-bearing mice were performed. This compound showed high accumulation in tumor tissue with high tumor-to-muscle and tumor-to-blood ratios. Thus, 99mTc-HYNIC-Bombesin(7–14) could be used as an agent for tumor diagnosis. 相似文献
933.
A commonly held principle in visual ecology is that communication compromises camouflage: while visual signals are often conspicuous, camouflage provides concealment. However, some traits may have evolved for communication and camouflage simultaneously, thereby overcoming this functional compromise. Visual patterns generally provide camouflage, but it was suggested that a particular type of visual pattern – avian barred plumage – could also be a signal of individual quality. Here, we test if the evolution of sexual dimorphism in barred plumage, as well as differences between juvenile and adult plumage, indicate camouflage and/or signalling functions across the class Aves. We found a higher frequency of female- rather than male-biased sexual dimorphism in barred plumage, indicating that camouflage is its most common function. But we also found that, compared to other pigmentation patterns, barred plumage is more frequently biased towards males and its expression more frequently restricted to adulthood, suggesting that barred plumage often evolves or is maintained as a sexual communication signal. This illustrates how visual traits can accommodate the apparently incompatible functions of camouflage and communication, which has implications for our understanding of avian visual ecology and sexual ornamentation. 相似文献
934.
Ricardo Cardoso Neves Marina Ribeiro da Cunha Peter Funch Andreas Wanninger Reinhardt Møbjerg Kristensen 《Helgoland Marine Research》2010,64(3):257-262
Cycliophora is a recently described phylum to which only two species have been assigned so far, Symbion pandora and S. americanus. The cycliophoran life cycle is complex and alternates between asexual and sexual stages. Although not recognized as an entirely
independent free-swimming stage when the phylum was first described, the dwarf male has a remarkably complex bodyplan albeit
its very small size (approx. 30–40 μm in length). Aiming to increase the knowledge on the gross morphology of the cycliophoran
dwarf male, specimens from S. pandora and S. americanus were analyzed by scanning electron microscopy. In both species, anterior and ventral ciliated fields, as well as paired lateral
sensorial organs, were identified, thus confirming previous observations. However, new details are described herein such as
the penial pouch that encloses the penis. We compare our findings on both Symbion species with the data currently available on other metazoan dwarf males. 相似文献
935.
Background
Females often express the same ornaments as males to a similar or lesser degree. Female ornaments can be adaptive, but little is known regarding their origins and mode of evolution. Current utility does not imply evolutionary causation, and therefore it is possible that female ornamentation evolved due to selection on females, as a correlated response to selection on males (sexual constraint), or a combination of both. We tested these ideas simulating simple models for the evolution of male and female correlated traits, and compared their predictions against the coloration of finches in the genus Carduelis. 相似文献936.
João CR Cardoso Florbela A Vieira Ana S Gomes Deborah M Power 《BMC evolutionary biology》2010,10(1):135
Background
The secretin family is a pleotropic group of brain-gut peptides with affinity for class 2 G-protein coupled receptors (secretin family GPCRs) proposed to have emerged early in the metazoan radiation via gene or genome duplications. In human, 10 members exist and sequence and functional homologues and ligand-receptor pairs have been characterised in representatives of most vertebrate classes. Secretin-like family GPCR homologues have also been isolated in non-vertebrate genomes however their corresponding ligands have not been convincingly identified and their evolution remains enigmatic. 相似文献937.
Ruth Landau John C. Kraft Lisa Y. Flint Brendan Carvalho Philippe Richeb�� Monica Cardoso Patricia Lavand��homme Michal Granot David Yarnitsky Alex Cahana 《Journal of visualized experiments : JoVE》2010,(35)
Many women undergo cesarean delivery without problems, however some experience significant pain after cesarean section. Pain is associated with negative short-term and long-term effects on the mother. Prior to women undergoing surgery, can we predict who is at risk for developing significant postoperative pain and potentially prevent or minimize its negative consequences? These are the fundamental questions that a team from the University of Washington, Stanford University, the Catholic University in Brussels, Belgium, Santa Joana Women''s Hospital in São Paulo, Brazil, and Rambam Medical Center in Israel is currently evaluating in an international research collaboration. The ultimate goal of this project is to provide optimal pain relief during and after cesarean section by offering individualized anesthetic care to women who appear to be more ''susceptible'' to pain after surgery.A significant number of women experience moderate or severe acute post-partum pain after vaginal and cesarean deliveries. 1 Furthermore, 10-15% of women suffer chronic persistent pain after cesarean section. 2 With constant increase in cesarean rates in the US 3 and the already high rate in Brazil, this is bound to create a significant public health problem. When questioning women''s fears and expectations from cesarean section, pain during and after it is their greatest concern. 4 Individual variability in severity of pain after vaginal or operative delivery is influenced by multiple factors including sensitivity to pain, psychological factors, age, and genetics. The unique birth experience leads to unpredictable requirements for analgesics, from ''none at all'' to ''very high'' doses of pain medication. Pain after cesarean section is an excellent model to study post-operative pain because it is performed on otherwise young and healthy women. Therefore, it is recommended to attenuate the pain during the acute phase because this may lead to chronic pain disorders. The impact of developing persistent pain is immense, since it may impair not only the ability of women to care for their child in the immediate postpartum period, but also their own well being for a long period of time.In a series of projects, an international research network is currently investigating the effect of pregnancy on pain modulation and ways to predict who will suffer acute severe pain and potentially chronic pain, by using simple pain tests and questionnaires in combination with genetic analysis. A relatively recent approach to investigate pain modulation is via the psychophysical measure of Diffuse Noxious Inhibitory Control (DNIC). This pain-modulating process is the neurophysiological basis for the well-known phenomenon of ''pain inhibits pain'' from remote areas of the body. The DNIC paradigm has evolved recently into a clinical tool and simple test and has been shown to be a predictor of post-operative pain.5 Since pregnancy is associated with decreased pain sensitivity and/or enhanced processes of pain modulation, using tests that investigate pain modulation should provide a better understanding of the pathways involved with pregnancy-induced analgesia and may help predict pain outcomes during labor and delivery. For those women delivering by cesarean section, a DNIC test performed prior to surgery along with psychosocial questionnaires and genetic tests should enable one to identify women prone to suffer severe post-cesarean pain and persistent pain. These clinical tests should allow anesthesiologists to offer not only personalized medicine to women with the promise to improve well-being and satisfaction, but also a reduction in the overall cost of perioperative and long term care due to pain and suffering. On a larger scale, these tests that explore pain modulation may become bedside screening tests to predict the development of pain disorders following surgery. 相似文献
938.
939.
Becky E. Raboy Leonardo G. Neves Sara Zeigler Nicholas A. Saraiva Nayara Cardoso Gabriel Rodrigues dos Santos Jonathan D. Ballou Peter Leimgruber 《Biotropica》2010,42(3):388-397
We investigated the effects of forest fragmentation on golden-headed lion tamarins (Leontopithecus chrysomelas) by qualitatively and quantitatively characterizing the landscape throughout the species range, conducting surveys, and exploring predictive models of presence and absence. We identified 784 forest patches that varied in size, shape, core area, habitat composition, elevation, and distance to neighboring patches and towns. We conducted 284 interviews with local residents and 133 playback experiments in 98 patches. Results indicated a reduction in the western portions of the former species range. We tested whether L. chrysomelas presence or absence was related to the aforementioned fragmentation indices using Monte Carlo logistic regression techniques. The analysis yielded a majority of iterations with a one-term final model of which Core Area Index (percent of total area that is core) was the only significant type. Model concordance ranged between 65 and 90 percent. Area was highlighted for its potential predictive ability. Although final models for area lacked significance, their failure to reach significance was marginal and we discuss potential confounding factors weakening the term's predictive ability. We conclude that lower Core Area Index scores are useful indicators of forest patches at risk for not supporting L. chrysomelas. Taken together, our analyses of the landscape, survey results, and logistic regression modeling indicated that the L. chrysomelas metapopulation is facing substantial threat. The limited vagility of lion tamarins in nonforest matrix may lead to increasingly smaller and inbred populations subject to significant impact from edge effects and small population size. Local extinction is imminent in many forest patches in the L. chrysomelas range. 相似文献
940.
Rosângela V Andrade Hugo C Paes André M Nicola Maria José A de Carvalho Ana Lúcia Fachin Renato S Cardoso Simoneide S Silva Larissa Fernandes Silvana P Silva Eduardo A Donadi Elza T Sakamoto-Hojo Geraldo AS Passos Célia MA Soares Marcelo M Brígido Maria Sueli S Felipe 《BMC genomics》2006,7(1):1-13