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11.
The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry captures information on interstage management of infants with hypoplastic left heart syndrome (HLHS). The purpose of this study was to identify interstage risk factors for increased resource use and adverse outcomes during bidirectional Glenn (BDG) hospitalization. All infants in the NPC-QIC registry (31 United States hospitals) undergoing BDG surgery were included (December 2009 to August 2010). Patient demographics, interstage variables, operative procedures, and complications were recorded. Days of hospitalization, ventilation, inotrope use, and complications were surrogates of resource use. Logistic regression analysis determined the associations between predictor variables and resource use. Of 162 infants, 105 (65 %) were males. At BDG, the median age was 155 days (range 78–128), mean weight-for-age z-score was ?1.6 ± 1.1, mean length-for-age z-score was ?1.5 ± 1.7, and mean preoperative oxygen saturation was 78 % ± 7 %. Caloric recommendations were met in 60 % of patients, and 85 % of patients participated in a home-surveillance program. Median days of intubation, inotrope use, and hospitalization were 1, 2, and 7, respectively. There were 4 post-BDG deaths and 55 complications. In multivariate analysis, lower weight-for-age z-score, female sex, and aortic atresia with mitral stenosis were associated with a higher risk of BDG complications. Meeting caloric recommendations before BDG was associated with fewer hospitalization days. Lower weight-for-age z-score was an independent and potentially modifiable risk factor for BDG complications. HLHS infants who met caloric recommendations before BDG had a lower duration of hospitalization at BDG. These data justify targeting nutrition in interstage strategies to improve outcomes and decrease costs for patients with HLHS.  相似文献   
12.
OBJECTIVES: To investigate the association between occupational social class and cardiovascular disease (CVD) incidence, and the extent to which classical and lifestyle risk factors explain such relationships, and if any differences persist after 65 years of age. DESIGN, SETTING AND PARTICIPANTS: Prospective population study of 22,478 men and women aged 39-79 years living in the general community in Norfolk, United Kingdom, recruited using general practice age-sex registers in 1993-1997 and followed up for total mortality to 2006. MAIN RESULTS: In both men and women an inverse relationship was observed between social class and CVD incidence, with a relative risk of social class V compared to I of 1.90 in men (95% CI 1.47 to 2.47, P < 0.001) and 1.90 in women (95% CI 1.45 to 2.49, P < 0.001). Adjusting for classical and lifestyle risk factors (age, smoking, BMI, systolic blood pressure, total blood cholesterol, history of diabetes, physical activity, weekly alcohol intake and plasma vitamin C levels) had little effect in men; the relative risk of social class V compared to I of 1.70 (95% CI 1.31 to 2.22, P < 0.001), while there was some attenuation seen in women, relative risk of social class V compared to I of 1.56 (95% CI 1.18 to 2.05, P = 0.011). The association persisted in men and women aged > or =65 years. CONCLUSIONS: Some but not all of the socioeconomic differential in CVD incidence can be explained by potentially modifiable classical and lifestyle risk factors. Low social class remains a risk factor for CVD after age 65 years. Further understanding of the mechanisms underlying the association is needed if we are to reduce inequalities in health.  相似文献   
13.
C-terminal deletions in the ALAS2 gene lead to gain of function and cause X-linked dominant protoporphyria without anemia or iron overload
Whatley et al. (2008)
The American Journal of Human Genetics 83: 408–414  相似文献   
14.
Red blood cells infected with Plasmodium falciparum (iRBCs) have been shown to modulate maturation of human monocyte-derived dendritic cells (DCs), interfering with their ability to activate T cells. Interaction between Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) and CD36 expressed by DCs is the proposed mechanism, but we show here that DC modulation does not require CD36 binding, PfEMP1, or contact between DCs and infected RBCs and depends on the iRBC dose. iRBCs expressing a PfEMP1 variant that binds chondroitin sulfate A (CSA) but not CD36 were phagocytosed, inhibited lipopolysaccharide (LPS)-induced phenotypic maturation and cytokine secretion, and abrogated the ability of DCs to stimulate allogeneic T-cell proliferation. CD36- and CSA-binding iRBCs showed comparable inhibition. P. falciparum lines rendered deficient in PfEMP1 expression by targeted gene knockout or knockdown also inhibited LPS-induced phenotypic maturation, and separation of DCs and iRBCs in transwells showed that inhibition was not contact dependent. Inhibition was observed at an iRBC:DC ratio of 100:1 but not at a ratio of 10:1. High doses of iRBCs were associated with apoptosis of DCs, which was not activation induced. Lower doses of iRBCs stimulated DC maturation sufficient to activate autologous T-cell proliferation. In conclusion, modulation of DC maturation by P. falciparum is dose dependent and does not require interaction between PfEMP1 and CD36. Inhibition and apoptosis of DCs by high-dose iRBCs may or may not be physiological. However, our observation that low-dose iRBCs initiate functional DC maturation warrants reevaluation and further investigation of DC interactions with blood-stage P. falciparum.  相似文献   
15.
16.
Members of the Poxviridae family are particularly adept at avoiding the host immune system, encoding a plethora of immunomodulatory proteins that subvert host defense. With their large genome, poxviruses are also useful for studying the effect of exogenous genes on virus-host interactions and immune responses. The insertion of the Th2 cytokine interleukin-4 (IL-4) into several poxviruses significantly increases the efficiency of the recombinant virus as a pathogen by directly inhibiting the development of Th1 immunity, which is crucial for viral clearance. In an age in which the fear of genetically modified weaponized pathogens exists, the understanding of how to make viruses more pathogenic further blurs the distinction between fundamental academic research and bioweapons development. Here, the extent of immune evasion by IL-4-expressing poxviruses will be explored, as will the consequences of this increased pathogenicity on protective immune responses.  相似文献   
17.
The virulence of different isolates of MAC was studied in naturally susceptible BALB/c mice. In preliminary experiments, MAC bacteria forming smooth transparent colonies on solid media (SmT variants) were found to be virulent for BALB/c mice, causing progressive infection; smooth opaque (SmOp) were generally avirulent, being slowly eliminated from the infected organs; and rough (Rg) variants were either avirulent or as virulent as SmT variants. We chose to compare the virulence of different isolates of MAC of different origins, studying only the SmT morphotype. Strains of MAC isolated from naturally infected animals were those that most consistently caused progressive infections. AIDS patients-derived isolates were of intermediate virulence or devoid of virulence in mice. The environmental strains were eliminated from mice or did not proliferate. Strains of MAC isolated from individuals who were not infected by HIV varied in virulence from completely avirulent to highly virulent. There was no close correlation between virulence and restriction fragment length polymorphism (RFLP) type, although all highly virulent strains were of the A/I type. There was also no correlation between virulence analysed in vivo and the ability to grow in cultured macrophages.  相似文献   
18.
The role that maternal and fetal human leukocyte antigen (HLA) genes play in pregnancy is unknown, but it has been suggested that fetuses whose HLA alleles do not differ from maternal alleles (i.e. histocompatible fetuses) are more likely to be aborted than fetuses with HLA alleles that differ from maternal alleles (i.e. histoincompatible fetuses). To elucidate the role of HLA compatibility in pregnancy, we tested the hypothesis that couples who match for HLA alleles or haplotypes would have reduced fertility because only these couples could produce histocompatible fetuses. We conducted a 10 year prospective study of HLA matching and pregnancy outcome in 111 Hutterite couples, providing information on 251 pregnancies. A logistic regression analysis was performed to determine the effects of HLA matching at HLA regions and loci on pregnancy outcome (fetal loss versus delivery). Significantly increased fetal loss rates were observed among couples matching for the entire 16-locus haplotype (P = 0.002). Among the individual loci, loss rates were increased among couples matching for HLA-B (P = 0.019), HLA-C (P = 0.033) and the complement component, C4 (P = 0.043). We interpret these results as evidence that matching for the entire 16-locus haplotype and/or alleles at an HLA-B-linked locus confers significant risk for fetal loss.   相似文献   
19.
Attitudes about genetic risk of couples undergoing in-vitro fertilization   总被引:1,自引:0,他引:1  
Many couples undergoing in-vitro fertilization (IVF) are at a higher risk of having a child with a genetic abnormality. In a sample of 55 consecutive couples starting IVF, only 33% had no genetic risk factor. The most common genetic risks were advanced maternal age and possible abnormalities associated with severe male infertility. Despite education on these risks, 71% of couples had no interest in receiving formal genetic counselling. Only 14% of couples at risk would consider using a gamete donor to avoid transmitting a genetic disorder to a child. The triple test to screen for fetal abnormalities was acceptable to 82% of couples, but only 47% planned to have amniocentesis or chorionic villi sampling. Couples were significantly more likely to opt for prenatal testing if they would consider terminating a pregnancy should the fetus have a severe genetic abnormality (P < 0.01). Roman Catholic couples tended to have more conservative attitudes about pregnancy termination. Socio-economic status and whether the infertility factor was male or female were not predictors of a couple's attitudes.   相似文献   
20.
Ryan KA, Vederman AC, McFadden EM, Weldon AL, Kamali M, Langenecker SA, McInnis MG. Differential executive functioning performance by phase of bipolar disorder. Bipolar Disord 2012: 14: 527–536. © 2012 The Authors. Journal compilation © 2012 John Wiley & Sons A/S. Objective: This study examined the influence of illness phase on executive functioning performance using factor‐derived cognitive scores in a cross‐sectional design. Methods: Healthy control (HC) subjects (n = 57), and euthymic (E‐BD) (n = 117), depressed (D‐BD) (n = 73), and hypomanic/mixed (HM/M‐BD) (n = 26) patients with bipolar disorder (BD) were evaluated using executive functioning measures (Wisconsin Card Sorting Test, Trail Making Test–Parts A and B, Verbal Fluency, Parametric Go/No‐Go, Stroop, and Digit Symbol) comprising Conceptual Reasoning and Set‐Shifting (CRSS), Processing Speed with Interference Resolution (PSIR), Verbal Fluency and Processing Speed (VFPS), and Inhibitory Control (IC) factor scores. Results: Two of the four executive functioning factors were significantly different between groups based upon phase of illness. The HM/M group was significantly worse than both of the other BD groups and the HC group in IC. The VFPS factor was sensitive to the active phase of BD, with the HM/M‐BD and D‐BD groups worse than HC. Extending our prior work, the PSIR factor, and now the CRSS factor were significantly worse in BD relative to HC, irrespective of phase of illness. Conclusions: Phase of illness had differential cognitive profiles in executive functioning factors, even after considering and excluding the impact of clinical features, illness characteristics, medications, and demographics. Consolidating executive functioning tasks into reliable factor scores provides unique information to measure and define cognitive deficiencies throughout phases of BD, and to measure intermediate phenotypes in BD, and may aid in tracking and clarifying treatment focus.  相似文献   
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