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101.
Clinical and molecular characterization of seven Egyptian families with autosomal recessive robinow syndrome: Identification of four novel ROR2 gene mutations 下载免费PDF全文
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Karen Ruby Lionel Jacob John Nagamani Sen 《Indian Journal of Critical Care Medicine》2014,18(1):21-25
Background and Aim:
Although large studies have demonstrated the association between hyperglycemia and adverse intensive care unit (ICU) outcomes, it is yet unclear which subset of patients benefit from tight sugar control in ICU. Recent evidence suggests that stress induced hyperglycemia (SIH) and co-incidentally detected diabetes mellitus are different phenomena with different prognoses. Differentiating SIH from diabetic hyperglycemia is challenging in ICU settings. We followed a cohort of trauma patients admitted to a surgical intensive care unit (SICU) to evaluate if initial glycated hemoglobin A (HbA1c) level predicts the outcome of admission.Materials and Methods:
A cohort of 120 consecutive admissions to SICU following trauma were recruited and admission blood sugar and HbA1c were measured. Outcomes were prospectively measured by blinded ICU doctors. A logistic regression model was developed to assess if HbA1c predicts poor outcomes in these settings.Results:
Nearly 24% of the participants had HbA1c ≥ 6. Those with HbA1c ≥ 6 had 3.14 times greater risk of poor outcome at the end of hospital stay when compared to those with HbA1c < 6 and this risk increased to an odds ratio of 4.57 on adjusting for other significant predictors: Acute Physiology and Chronic Health Evaluation II, injury severity score, admission blood sugar and age at admission.Conclusions:
Substantial proportion of trauma admissions has underlying diabetes. HbA1c, a measure of pre admission glycaemic status is an important predictor of ICU outcome in trauma patients. 相似文献106.
Isabel M. Scott Andrew P. Clark Steven C. Josephson Adam H. Boyette Innes C. Cuthill Ruby L. Fried Mhairi A. Gibson Barry S. Hewlett Mark Jamieson William Jankowiak P. Lynne Honey Zejun Huang Melissa A. Liebert Benjamin G. Purzycki John H. Shaver J. Josh Snodgrass Richard Sosis Lawrence S. Sugiyama Viren Swami Douglas W. Yu Yangke Zhao Ian S. Penton-Voak 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(40):14388-14393
A large literature proposes that preferences for exaggerated sex typicality in human faces (masculinity/femininity) reflect a long evolutionary history of sexual and social selection. This proposal implies that dimorphism was important to judgments of attractiveness and personality in ancestral environments. It is difficult to evaluate, however, because most available data come from large-scale, industrialized, urban populations. Here, we report the results for 12 populations with very diverse levels of economic development. Surprisingly, preferences for exaggerated sex-specific traits are only found in the novel, highly developed environments. Similarly, perceptions that masculine males look aggressive increase strongly with development and, specifically, urbanization. These data challenge the hypothesis that facial dimorphism was an important ancestral signal of heritable mate value. One possibility is that highly developed environments provide novel opportunities to discern relationships between facial traits and behavior by exposing individuals to large numbers of unfamiliar faces, revealing patterns too subtle to detect with smaller samples.Inspired by evidence from nonhuman species indicating that exaggerated sex-typical traits (e.g., large antlers, peacock tails) are often attractive to mates or intimidating to rivals (1, 2), morphological sex typicality in humans (masculinity in men and femininity in women) has been the focus of considerable research into attractiveness judgments (3, 4). Facial attractiveness research has been revolutionized by this explanatory framework from the biological sciences, which proposes that attractive human faces honestly signaled mate value within ancestral environments.An influential proposal is that facial femininity is a signal of fertility in human female faces (4–9) because, within same-age women, it is associated with estrogens (10), which, in turn, are related to measures of reproductive health (11). Like ovarian function, facial femininity declines with age in adulthood (12, 13). The proposal that fertile women should be attractive to men is seemingly uncontroversial because males who discriminatively mate with fertile females should achieve a straightforward reproductive advantage over those males who do not, with all other factors being equal (6). Although direct associations between facial femininity and fertility have not been demonstrated, the consensus from Western preferences, and from the limited cross-cultural data available, is that femininity is attractive, as predicted by the fertility hypothesis (14–17). In environments where fertility is high and variable, this relationship should be even more apparent.In male faces, masculinity has been variously proposed to signal heritable disease resistance (“good genes” or “immunocompetence”) (4, 15, 18–22) and/or perceived as a cue of aggressiveness and, consequently, intrasexual competitiveness (22, 23). The “honesty” of face shape as an indicator of immunocompetence is proposed to be the result of an immunosuppressive effect of testosterone. Because testosterone influences the growth of sex-typical traits in many species (24, 25), masculine facial shape is proposed to be a costly, and thus honest, signal of male quality (22). The hypothesis that cues of heritable health should be attractive to females is widely accepted (26), although the evidence for a link between heritable health and masculinity in humans is tentative at best (22).Support for a link between masculinity and aggression is largely indirect, and it consists of an association between testosterone and both aggressive behavior (27, 28) and face shape (25), in addition to the fact that honest signaling of dominance is commonly observed in nonhuman species (3). Masculine faces are perceived as aggressive in those groups (i.e., urban, Western) where the relationship has been tested (29). Because masculinity may signal both (desirable) immunity and (potentially costly) aggression in humans, some authors have proposed that preferences for masculinity reflect women trading-off benefits of traits putatively associated with health against those traits associated with prosocial behaviors, such as parental investment (23, 30, 31).Consistent with both of these proposals, data indicate that preferences for masculinity are stronger in circumstances where indirect benefits (heritable quality) can be realized without accompanying direct costs (aggression and low paternal investment). Such circumstances include judging attractiveness in the context of a short-term (vs. a long-term) relationship (32) and in the follicular phase of the menstrual cycle when conception following intercourse is most likely (33). Masculinity is also reported to be more strongly preferred in environments with relatively high pathogen burdens (19, 30) and in environments with higher local homicide rates (23), which has been interpreted as a response to variation in the benefits of heritable disease resistance (19) and in the net benefits conferred by aggressive males under varying levels of male–male competition (23).All of this supporting evidence comes with a very important caveat; although there has been some cross-cultural work in this area (34), the majority of studies have been conducted in Western, often student, populations characterized by high levels of development and urbanization [Western, educated, industrialized, rich, and democratic; so-called WEIRD participants (35)]. Research on preferences in other groups is scant and methodologically inconsistent, using Internet-based designs or a limited cross-cultural component (7, 15–18). Because there are differences between Western/non-Western and industrial/small-scale societies in many behaviors, including aspects of visual perception and mate choice (35), this over-representation greatly limits generalizability. Perhaps most importantly, large-scale (post)industrial societies present inhabitants with large numbers of unfamiliar faces and provide venues for the efficient exchange of (visual) social information (e.g., posters, television, Internet); these factors may be instrumental in the acquisition and reinforcement of preferences (36–39). It is possible therefore that rather than being a legacy of ancestral selection pressures, preferences for dimorphism emerge in large urban groups as a byproduct of the information-processing strategies used to process large amounts of social information or in response to arbitrary cultural norms.Development also introduces an increased presence of highly differentiated social roles that arise from a greater division of labor, along with opportunities to acquire prestige without strength or aggression. Because partner preferences have been proposed to develop in response to sex-typical social roles (40, 41), it is possible that increasingly differentiated roles could influence masculinity preferences if desirable social roles not present in less developed groups are associated with facial appearance.We assessed preferences for, and trait attributions made to, faces varying in dimorphism in a cross-cultural sample of 12 groups, including non-Western, nonstudent, and small-scale societies (n = 962; Tables S1 and S2). We tested the predictions, derived from the immunocompetence handicapping hypothesis, that (i) preferences for dimorphism will be stronger in less developed groups and (ii) masculine faces would be perceived as aggressive in all populations, with perceptions in low-development groups at least as strong as in groups with high development. We estimated social development with the Human Development Index (HDI), which is a composite indicator compiled by the United Nations Development Program. To investigate which aspects of development were associated with variation in perception of our facial stimuli, we took the World Health Organization measures of years lost to disease and United Nations (UN) measures of homicide rates as proxy measures of disease burden and male intrasexual competition, respectively (both log-transformed), and UN measures of levels of urbanization. Using these national statistics almost certainly underestimates disease burden in the small-scale societies in our sample, which is a conservative estimate with regard to our hypotheses.
Open in a separate windowParticipants were asked to choose the most attractive face from five sets (representing five different ethnicities, representing considerable phenotypic variation in human faces) of three opposite-sex photographs, with one 60% masculinized [i.e., with the shape differences between male and female faces caricatured by 60% (4)], one 60% feminized, and one unaltered face in each set (Fig. 1). Participants assessed attractiveness for long-term and short-term relationships. Participants were also asked to choose the most aggressive-looking face, and responses were scored in the same way. Custom randomization tests were used to test for nonrandomness of choice (e.g., Fig. S1), and ordinal generalized linear mixed models (GLMMs) were used to test for associations between choices and predictor variables.Open in a separate windowFig. 1.Examples of stimuli used. A European female composite (Upper) and an East Asian male composite (Lower) are shown. Masculinized stimuli (Left) and feminized stimuli (Right) are shown.Although the previous literature suggests that familiarity effects of ethnicity can subtly affect dimorphism preferences, this influence is small and inconsistent across cultures and is unlikely to bias results as a result of exposure to ethnic variation in facial appearance (4, 15). 相似文献
Table 1.
Summary information for the groups testedGroup | Local region | Country | Subsistence mode | n male | n female | n female after exclusions |
Canadian students | Alberta province | Canada | Market economy | 23 | 60 | 18 |
UK students | Bristol city | United Kingdom | Market economy | 80 | 238 | 134 |
Shanghai students | Shanghai municipality | China | Market economy | 41 | 38 | 38 |
Hangzhou citizens | Zhejiang province | China | Market economy | 43 | 52 | 48 |
Cree Canadians | Alberta province | Canada | Market economy | 26 | 28 | 13 |
Tuvans | Tyva Republic | Russia | Pastoralism, wages | 30 | 30 | 18 |
Kadazan-Dusun | Sabah region | Malaysia | Pastoralism, agriculture | 25 | 26 | 18 |
Fijian villagers | Cakaudrove province | Fiji | Foraging, agriculture, wages | 9 | 10 | 5 |
Shuar | Morona Santiago province | Ecuador | Horticulture, hunting, foraging, recent small-scale agropastoralism | 30 | 31 | 19 |
Miskitu | Región Autónoma del Atlántico Sur | Nicaragua | Horticulture, fishing, hunting | 13 | 17 | 15 |
Tchimba | Kunene region | Namibia | Pastoralism | 35 | 27 | 20 |
Aka | Southwest Central African Republic | Central African Republic | Foraging | 25 | 25 | 11 |
107.
Yamamura A Guo Q Yamamura H Zimnicka AM Pohl NM Smith KA Fernandez RA Zeifman A Makino A Dong H Yuan JX 《Circulation research》2012,111(4):469-481
Rationale: A rise in cytosolic Ca(2+) concentration ([Ca(2+)](cyt)) in pulmonary arterial smooth muscle cells (PASMC) is an important stimulus for pulmonary vasoconstriction and vascular remodeling. Increased resting [Ca(2+)](cyt) and enhanced Ca(2+) influx have been implicated in PASMC from patients with idiopathic pulmonary arterial hypertension (IPAH). Objective: We examined whether the extracellular Ca(2+)-sensing receptor (CaSR) is involved in the enhanced Ca(2+) influx and proliferation in IPAH-PASMC and whether blockade of CaSR inhibits experimental pulmonary hypertension. Methods and Results: In normal PASMC superfused with Ca(2+)-free solution, addition of 2.2 mmol/L Ca(2+) to the perfusate had little effect on [Ca(2+)](cyt). In IPAH-PASMC, however, restoration of extracellular Ca(2+) induced a significant increase in [Ca(2+)](cyt). Extracellular application of spermine also markedly raised [Ca(2+)](cyt) in IPAH-PASMC but not in normal PASMC. The calcimimetic R568 enhanced, whereas the calcilytic NPS 2143 attenuated, the extracellular Ca(2+)-induced [Ca(2+)](cyt) rise in IPAH-PASMC. Furthermore, the protein expression level of CaSR in IPAH-PASMC was greater than in normal PASMC; knockdown of CaSR in IPAH-PASMC with siRNA attenuated the extracellular Ca(2+)-mediated [Ca(2+)](cyt) increase and inhibited IPAH-PASMC proliferation. Using animal models of pulmonary hypertension, our data showed that CaSR expression and function were both enhanced in PASMC, whereas intraperitoneal injection of the calcilytic NPS 2143 prevented the development of pulmonary hypertension and right ventricular hypertrophy in rats injected with monocrotaline and mice exposed to hypoxia. Conclusions: The extracellular Ca(2+)-induced increase in [Ca(2+)](cyt) due to upregulated CaSR is a novel pathogenic mechanism contributing to the augmented Ca(2+) influx and excessive PASMC proliferation in patients and animals with pulmonary arterial hypertension. 相似文献
108.
Ocean barrier layers' effect on tropical cyclone intensification 总被引:5,自引:0,他引:5
K Balaguru P Chang R Saravanan LR Leung Z Xu M Li JS Hsieh 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(36):14343-14347
Improving a tropical cyclone's forecast and mitigating its destructive potential requires knowledge of various environmental factors that influence the cyclone's path and intensity. Herein, using a combination of observations and model simulations, we systematically demonstrate that tropical cyclone intensification is significantly affected by salinity-induced barrier layers, which are "quasi-permanent" features in the upper tropical oceans. When tropical cyclones pass over regions with barrier layers, the increased stratification and stability within the layer reduce storm-induced vertical mixing and sea surface temperature cooling. This causes an increase in enthalpy flux from the ocean to the atmosphere and, consequently, an intensification of tropical cyclones. On average, the tropical cyclone intensification rate is nearly 50% higher over regions with barrier layers, compared to regions without. Our finding, which underscores the importance of observing not only the upper-ocean thermal structure but also the salinity structure in deep tropical barrier layer regions, may be a key to more skillful predictions of tropical cyclone intensities through improved ocean state estimates and simulations of barrier layer processes. As the hydrological cycle responds to global warming, any associated changes in the barrier layer distribution must be considered in projecting future tropical cyclone activity. 相似文献
109.
S McGowan AM Buckle MS Mitchell JT Hoopes DT Gallagher RD Heselpoth Y Shen CF Reboul RH Law VA Fischetti JC Whisstock DC Nelson 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):12752-12757
Bacteriophages deploy lysins that degrade the bacterial cell wall and facilitate virus egress from the host. When applied exogenously, these enzymes destroy susceptible microbes and, accordingly, have potential as therapeutic agents. The most potent lysin identified to date is PlyC, an enzyme assembled from two components (PlyCA and PlyCB) that is specific for streptococcal species. Here the structure of the PlyC holoenzyme reveals that a single PlyCA moiety is tethered to a ring-shaped assembly of eight PlyCB molecules. Structure-guided mutagenesis reveals that the bacterial cell wall binding is achieved through a cleft on PlyCB. Unexpectedly, our structural data reveal that PlyCA contains a glycoside hydrolase domain in addition to the previously recognized cysteine, histidine-dependent amidohydrolases/peptidases catalytic domain. The presence of eight cell wall-binding domains together with two catalytic domains may explain the extraordinary potency of the PlyC holoenyzme toward target bacteria. 相似文献
110.
TM Husain DE Garrido A Aziz-Sultan JC Tang CJ Salgado 《The Journal of craniofacial surgery》2012,23(5):e380-e384
ABSTRACT: Arterial venous malformations (AVMs) are rare conditions that are difficult to manage. Therapeutic options include selective embolization with or without surgical excision. Recurrence, however, is high despite correction of the primary abnormality. Cosmetic concern is among the indications for treatment, particularly if the AVM occurs on the face or scalp. Historically, AVM excision and the residual defect correction have been performed separately. We present the first case reported of a successful embolization and interval excision with immediate reconstruction using a dermal fat graft, as a novel approach to correct soft tissue defect following the resection of an AVM.A 35-year-old man presented with a 20-year history of a nonpulsating mass posterior to the hairline in the right frontoparietal region, measuring 4.0 cm on its longest axis. Embolization of the AVM was achieved by injecting N-butyl cyanoacrylic acid and ethiodol. One month after embolization, surgical excision of the mass was performed. The resulting disfiguring contour defect was immediately corrected using a dermal fat graft harvested from the groin. At 4 months' follow-up, the graft was viable with no evidence of resorption or epidermal cyst formation. In addition, there was no recurrence of the AVM and no complications at the donor site.This case demonstrates the utility of a dermal fat grafts in correcting the impending defect in 1 stage avoiding a second-stage procedure and significant period of cosmetic disfigurement. This method should be considered as a treatment option for patients requiring moderately sized AVM excisions in cosmetically sensitive areas. 相似文献