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1.
Rocío Santos-Gally Rocío Pérez-Barrales Violeta I. Simón Juan Arroyo 《Annals of botany》2013,111(2):317-328
Background and Aims
Heterostyly and related style polymorphisms are suitable model systems to evaluate the importance of functional pollinators in the maintenance of population variability. In Narcissus papyraceus different functional pollinators, incompatibility system and flower morphology have been proposed to influence the maintenance of polymorphism through their effect on disassortative mating. Here a test is done to find out if the visitation rate of long- versus short-tongued pollinators correlates with the morph ratio and if the latter is related to other flower traits of the species across its main geographic range.Methods
Floral traits from 34 populations in the south-west of the Iberian Peninsula and in north-west Africa were measured, perianth variation was described and a comparison was made of allometric relationships between sex organs and floral tube. Correlations between pollinator guilds, stigma–anther separation of reciprocal morphs (our proxy for disassortative mating) and morph-ratio variation were analysed. Finally, the incompatibility system of the species in the northern and southern borders of its distribution are described.Key Results
Flowers from southern populations were significantly larger than flowers from centre and northern populations. The abundance of short-styled plants decreased gradually with increasing distance from the core region (the Strait of Gibraltar), with these disappearing only in the northern range. Although there was a significant difference in stigma–anther separation among populations, morph ratio was not associated with reciprocity or floral tube length. Long-style morph frequency increased with short-tongued pollinator visitation rate. Populations from both edges of the distribution range were self-incompatible and within- and between-morph compatible.Conclusions
The style morph ratio changed gradually, whereas perianth trait variation showed abrupt changes with two morphotypes across the range. The positive relationship between the visitation rate of short-tongued pollinators and the decrease of the short-style morph supports our initial hypothesis. The results highlight the importance of different pollinators in determining the presence of style polymorphism. 相似文献2.
Kyoung-Nam Kim Jin Hee Kim Ho-Jang Kwon Soo-Jong Hong Byoung-Ju Kim So-Yeon Lee Yun-Chul Hong Sanghyuk Bae 《PloS one》2014,9(10)
Background
Although the effect of bisphenol A on various health outcomes has been extensively examined, few studies have investigated its effect on asthma.Objective
We hypothesized that exposure to bisphenol A in school-age children was associated with wheezing and asthma.Methods
Participants included 127 children aged 7–8 years without a previous asthma diagnosis in an elementary school in Seoul, Korea. Three surveys were conducted, each 2 years apart. Bisphenol A concentration was measured at the baseline survey, and PC20, which is defined as the methacholine concentration that induces a decrease in FEV1 of 20% from baseline, was measured at every survey. Associations between bisphenol A concentration at 7–8 years of age and wheezing, asthma, and PC20 at ages up to 11–12 years were examined using generalized estimating equations, a marginal Cox regression model, and a linear mixed model.Results
The log-transformed creatinine-adjusted urinary bisphenol A concentration at 7–8 years was positively associated with wheezing (odds ratio, 2.48; 95% confidence interval, 1.15–5.31; P = .02) and asthma (hazard ratio, 2.13; 95% confidence interval, 1.51–3.00; P<.001) at ages up to 11–12 years. Bisphenol A was also negatively associated with PC20 (ß = −2.33; P = .02). When stratified by sex, the association between bisphenol A and asthma remained significant only in girls (hazard ratio, 2.45; 95% confidence interval, 2.18–2.76; P<.001).Conclusion
Increased urinary bisphenol A concentrations at 7–8 years old were positively associated with wheezing and asthma and negatively associated with PC20 at ages up to 11–12 years. 相似文献3.
Andrea A. Jones Fidel Vila-Rodriguez William J. Panenka Olga Leonova Verena Strehlau Donna J. Lang Allen E. Thornton Hubert Wong Alasdair M. Barr Ric M. Procyshyn Geoffrey N. Smith Tari Buchanan Mel Krajden Michael Krausz Julio S. Montaner G. William MacEwan David J. Nutt William G. Honer 《PloS one》2013,8(11)
Background
The Independent Scientific Committee on Drugs (ISCD) assigned quantitative scores for harm to 20 drugs. We hypothesized that a personalized, ISCD-based Composite Harm Score (CHS) would be associated with poor health outcomes in polysubstance users.Methods
A prospective community sample (n=293) of adults living in marginal housing was assessed for substance use. The CHS was calculated based on the ISCD index, and the personal substance use characteristics over four weeks. Regression models estimated the association between CHS and physical, psychological, and social health outcomes.Results
Polysubstance use was pervasive (95.8%), as was multimorbid illness (median 3, possible range 0–12). The median CHS was 2845 (interquartile range 1865–3977). Adjusting for age and sex, every 1000-unit CHS increase was associated with greater mortality (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.07–2.01, p = 0.02), and persistent hepatitis C infection (OR 1.29, 95% CI 1.02–1.67, p = 0.04). The likelihood of substance-induced psychosis increased 1.39-fold (95% CI 1.13–1.67, p = 0.001). The amount spent on drugs increased 1.51-fold (1.40–1.62, p < 0.001) and the odds of having committed a crime increased 1.74-fold (1.46–2.10, p < 0.001). Multimorbid illness increased 1.43-fold (95% CI 1.26–1.63, p < 0.001).Conclusions
Greater CHS predicts poorer physical, psychological, and social health, and may be a useful quantitative, personalized measure of risk for drug-related harm. 相似文献4.
Background and Aims
It has been proposed that variation in pollinator preferences or a fluctuating environment can act to maintain flower colour polymorphism. These two hypotheses were tested in an aquatic monocot Butomus umbellatus (Butomaceae) with a pink or white gynoecium in the field population.Methods
Pollinator visitation was compared in experimental arrays of equivalent flowering cymes from both colour morphs. Seed set was compared between inter- and intramorph pollination under different water levels to test the effect of fluctuating environment on seed fertility.Key Results
Overall, the major pollinator groups did not discriminate between colour morphs. Compared with the white morph, seed production in the pink morph under intermorph, intramorph and open pollination treatments was significantly higher when the water level was low but not when it was high. Precipitation in July was correlated with yearly seed production in the pink morph but not in the white morph.Conclusions
The results indicated that the two colour morphs differed in their tolerance to water level. Our study on this aquatic plant provides additional evidence to support the hypothesis that flower colour polymorphism can be preserved by environmental heterogeneity. 相似文献5.
Background and Aims
Organisms may be polymorphic within natural populations, but often the significance and genetic background to such polymorphism is not known. To understand the colour polymorphism expressed in the diploid marsh-orchids Dactylorhiza incarnata, morphological, habitat and genetic differentiation was studied in mixed populations on the island of Gotland, supplemented with genetic marker data from adjacent areas.Methods
A total of 398 accessions was investigated for plastid haplotype and three nuclear microsatellites. Morphometric data and vegetation data were obtained from a subset of 104 plants.Key Results
No clear pattern of habitat differentiation was found among the colour morphs. Within sites, the yellow-flowered morph (ochroleuca) was slightly larger than the others in some flower characters, whereas the purple-flowered morph with spotted leaves (cruenta) was on average smaller. However, populations of the same colour morph differed considerably between sites, and there was also considerable overlap between morphs. Morphs were often genetically differentiated but imperfectly separated within sites. Most populations were characterized by significant levels of inbreeding. The ochroleuca morph constitutes a coherent, highly homozygous sublineage, although introgression from purple-flowered morphs occurs at some sites. The cruenta morph was genetically variable, although Gotland populations formed a coherent group. Purple-flowered plants with unspotted leaves (incarnata in the strict sense) were even more variable and spanned the entire genetic diversity seen in the other morphs.Conclusions
Colour polymorphism in D. incarnata is maintained by inbreeding, but possibly also by other ecological factors. The yellow-flowered morph may best be recognized as a variety of D. incarnata, var. ochroleuca, and the lack of anthocyanins is probably due to a particular recessive allele in homozygous form. Presence of spotted leaves is an uncertain taxonomic character, and genetic differentiation within D. incarnata would be better described by other morphological characters such as leaf shape and stature and size and shape of lip and spur.Key words: Dactylorhiza incarnata, cruenta, ecology, genetic differentiation, Gotland, microsatellites, ochroleuca, plastid DNA, polymorphism 相似文献6.
Background
C5 palsy is a serious but poorly understood complication after posterior cervical decompression that could lead to muscle weakness, brachialgia and numbness of the upper limbs. The incidence of C5 palsy varies greatly between studies. The risk factors are inconclusive and even conflicting.Object
To perform a systematic review on the incidence and risk factors of C5 palsy after posterior cervical decompression.Materials and Methods
Four databases, PubMed, Embase, Web of Science and Cochrane CENTRAL, were searched to identify eligible studies. Either a fixed- or a random-effects model was used to calculate the pooled odd ratio (RR) or standardized mean difference (SMD) with its 95% confidence interval (95%CI).Results
Of the 589 pre-recruited studies, 25 were included in this study for systematic review. The pooled incidence of C5 palsy after posterior decompression was 5.8% (95%CI: 4.4–7.2%). The incidence after open-door laminoplasty, double-door laminoplasty and laminectomy was 4.5%, 3.1% and 11.3%, respectively. The significant risk factors of C5 palsy were OPLL (OR, 2.188; 95%CI, 1.307–3.665), narrower intervertebral foramen (SMD, −0.972; 95%CI, −1.398 to −0.545), laminectomy (vs. open-door laminoplasty, OR, 2.988; 95%CI, 1.298–6.876), excessive spinal cord drift (SMD, 1.289, 95%CI, 0,197–2.381) and male gender (OR, 1.54; 95%CI, 1.036–2.301).Conclusions
The results of this systematic review suggest that patients with excessive spinal cord drift, preexisting intervertebral foramenal stenosis, OPLL, laminectomy and male gender are at high risk for postoperative C5 palsy, and risk-reduction options should be considered for such patients. 相似文献7.
Background and Aims
Floral polymorphism is frequently attributed to pollinator-mediated selection. Multiple studies, however, have revealed the importance of non-pollinating visitors in floral evolution. Using the polymorphic annual daisy Ursinia calenduliflora, this study investigated the importance of different insect visitors, and their effects on fitness, in the maintenance of floral polymorphism.Methods
The spatial structure of a discrete floral polymorphism was characterized based on the presence/absence of anthocyanin floret spots in U. calenduliflora. A 3-year observational study was then conducted in polymorphic populations to investigate differences in visitation rates of dominant visitors to floral morphs. Experiments were performed to explore the floral preference of male and female Megapalpus capensis (the dominant insect visitor) and their effectiveness as pollinators. Next, floral damage by antagonistic florivores and the reproductive success of the two floral morphs were surveyed in multiple populations and years.Key Results
Floral polymorphism in U. calenduliflora was structured spatially, as were insect visitation patterns. Megapalpus capensis males were the dominant visitors and exhibited strong preference for the spotted morph in natural and experimental observations. While this may indicate potential fitness benefits for the spotted morph, female fitness did not differ between floral morphs. However, as M. capensis males are very efficient at exporting U. calenduliflora pollen, their preference may likely increase the reproductive fitness of the spotted morph through male fitness components. The spotted morph, however, also suffered significantly greater costs due to ovule predation by florivores than the spotless morph.Conclusions
The results suggest that pollinators and florivores may potentially exert antagonistic selection that could contribute to the maintenance of floral polymorphism across the range of U. calenduliflora. The relative strength of selection imposed by each agent is potentially determined by insect community composition and abundance at each site, highlighting the importance of community context in the evolution of floral phenotypes. 相似文献8.
Isabelle Morard Sophie Clément Alexandra Calmy Alessandra Mangia Andrea Cerny Andrea De Gottardi Meri Gorgievski Markus Heim Raffaele Malinverni Darius Moradpour Beat Müllhaupt David Semela Stéphanie Pascarella Pierre-Yves Bochud Franco Negro 《PloS one》2014,9(9)
Background
The CCR5 receptor, expressed on Th1 cells, may influence clinical outcomes of HCV infection. We explored a possible link between a CCR5 32-base deletion (CCR5delta32), resulting in the expression of a non-functioning receptor, and clinical outcomes of HCV infection.Methods
CCR5 and HCV-related phenotypes were analysed in 1,290 chronically infected patients and 160 patients with spontaneous clearance.Results
Carriage of the CCR5delta32 allele was observed in 11% of spontaneous clearers compared to 17% of chronically infected patients (OR = 0.59, 95% CI interval 0.35–0.99, P = 0.047). Carriage of this allele also tended to be observed more frequently among patients with liver inflammation (19%) compared to those without inflammation (15%, OR = 1.38, 95% CI interval 0.99–1.95, P = 0.06). The CCR5delta32 was not associated with sustained virological response (P = 0.6), fibrosis stage (P = 0.8), or fibrosis progression rate (P = 0.4).Conclusions
The CCR5delta32 allele appears to be associated with a decreased rate of spontaneous HCV eradication, but not with hepatitis progression or response to antiviral therapy. 相似文献9.
Background
Ischemia-modified albumin is an altered serum albumin that forms under conditions of oxidative stress, a state also associated with doxorubicin-induced myocardial injury.Objective
The aim of this study was to better assess diagnostic and prognostic significance of ischemia-modified albumin in patients with breast cancer undergoing doxorubicin chemotherapy.Methods
Blood samples were collected from 152 breast cancer patients before and after each cycle of doxorubicin chemotherapy to measure the serum levels of ischemia-modified albumin, cardiac troponin T and creatine kinase-MB. We also monitored cardiac function during a 12 month follow-up.Results
There was a significant difference in ischemia-modified albumin levels before and after each cycle of chemotherapy and the ischemia-modified albumin concentration positively correlated with the cumulative dose of doxorubicin (r = 0.212, P < 0.05). The combination of ischemia-modified albumin with cardiac troponin T and creatine kinase-MB increased the sensitivity to 0.920 and the specificity to 0.830 in the diagnosis of doxorubicin-induced myocardial injury. The optimal cutoff for ischemia-modified albumin concentration was 112.09 U/ml. The rate of change for ischemia-modified albumin levels correlated negatively with the rate of change for left ventricular ejection fraction at one year (r = –0.221, P < 0.05).Conclusion
Ischemia-modified albumin may be a clinically potential new marker for diagnosing doxorubicin-induced myocardial injury, and is helpful to predict long-term impairment of cardiac function. 相似文献10.
Yu Lu Cuiju Mo Zhiyu Zeng Siyuan Chen Yantong Xie Qiliu Peng Yu He Yan Deng Jian Wang Li Xie Jie Zeng Shan Li Xue Qin 《PloS one》2013,8(12)
Background
Many epidemiological studies have been conducted to explore the association between a single CYP2D6 gene polymorphism and Parkinson’s disease (PD) susceptibility. However, the results remain controversial.Objectives
To clarify the effects of a single CYP2D6 gene polymorphism on the risk of PD, a meta-analysis of all available studies relating to CYP2D6*4 polymorphism and the risk of PD was conducted.Methods
A comprehensive literature search of PubMed, EMBASE, and the China National Knowledge Infrastructure (CNKI) up to September 1, 2013 was conducted. Data were extracted by two independent authors and pooled odds ratio (OR) with 95% confidence interval (CI) were calculated. Meta-regression, Galbraith plots, subgroup analysis, sensitivity analysis, and publication bias analysis were also performed.Results
Twenty-two separate comparisons consisting of 2,629 patients and 3,601 controls were included in our meta-analysis. The pooled analyses showed a significant association between CYP2D6*4G/A polymorphism and PD risk in all of the comparisons (A vs. G allele: OR = 1.28, 95% CI = 1.14–1.43, P = 0.001; AA vs. GG: OR = 1.43, 95% CI = 1.06–1.93, P = 0.018; AG vs. GG: OR = 1.22, 95% CI = 1.06–1.40, P = 0.006; AG+AA vs. GG: OR = 1.26, 95% CI = 1.10–1.44, P = 0.001; AA vs. AG+GG: OR = 1.37, 95% CI = 1.02–1.83, P = 0.036). In subgroup analysis stratified by ethnicity, significant associations were also demonstrated in Caucasians but not in Asians. No significant association was found in subgroup analysis stratified by age of onset or disease form.Conclusions
We concluded that the CYP2D6*4G/A polymorphism denotes an increased genetic susceptibility to PD in the overall population, especially in Caucasians. Further large and well-designed studies are needed to confirm this association. 相似文献11.
Chuiwen Deng Chaojun Hu Si Chen Jing Li Xiaoting Wen Ziyan Wu Yuan Li Fengchun Zhang Yongzhe Li 《PloS one》2015,10(1)
Purpose
To conduct a meta-analysis to evaluate the diagnostic value of anti-muscarinic receptor type 3 (M3R) antibodies in Sjögren syndrome (SS).Methods
Two databases, PUBMED and the Cochrane Library, were systematically searched. Approximately 2,000 participants from several studies were included in this research. STATA 11.2 software and Meta-DiSc 1.4 was used to conduct the meta-analysis.Results
Eleven studies were included in the meta-analysis. The pooled DOR was 13.00 (95% CI, 6.00–26.00). The sensitivity was 0.43 (95% CI, 0.28–0.58) and the specificity was 0.95 (95%CI, 0.91–0.97). The LR+ and LR- were 7.90 (95% CI, 4.70–13.40), 0.61 (95% CI, 0.46–0.79), respectively. The AUC was 0.89 (95% CI, 0.86–0.92).Conclusion
The anti-M3R antibody had high specificity but relatively low sensitivity for the diagnosis of SS. 相似文献12.
Jacques Montplaisir Dominique Petit Marie-Josée Quinn Manale Ouakki Geneviève Deceuninck Alex Desautels Emmanuel Mignot Philippe De Wals 《PloS one》2014,9(9)
Context
An association between an adjuvanted (AS03) A/H1N1 pandemic vaccine and narcolepsy has been reported in Europe.Objective
To assess narcolepsy risk following administration of a similar vaccine in Quebec.Design
Retrospective population-based study.Setting
Neurologists and lung specialists in the province were invited to report narcolepsy cases to a single reference centre.Population
Patients were interviewed by two sleep experts and standard diagnostic tests were performed. Immunization status was verified in the provincial pandemic influenza vaccination registry.Main Outcome Measures
Confirmed narcolepsy with or without cataplexy with onset of excessive daytime sleepiness between January 1st, 2009, and December 31st, 2010. Relative risks (RRs) were calculated using a Poisson model in a cohort analysis, by a self-controlled case series (SCCS) and a case-control method.Results
A total of 24 cases were included and overall incidence rate was 1.5 per million person-years. A cluster of 7 cases was observed among vaccinated persons in the winter 2009–2010. In the primary cohort analysis, 16-week post-vaccination RR was 4.32 (95% CI: 1.50–11.12). RR was 2.07 (0.70–6.17) in the SCCS, and 1.48 (0.37–7.03) using the case-control method. Estimates were lower when observation was restricted to the period of pandemic influenza circulation, and tended to be higher in persons <20 years old and for cataplexy cases.Conclusions
Results are compatible with an excess risk of approximately one case per million vaccine doses, mainly in persons less than 20 years of age. However, a confounding effect of the influenza infection cannot be ruled out. 相似文献13.
Shaoyong Xu Bin Gao Ying Xing Jie Ming Junxiang Bao Qiang Zhang Yi Wan Qiuhe Ji 《PloS one》2013,8(10)
Background
Not all the people with metabolic syndrome (MS) have abdominal obesity (AO). The study aimed to investigate gender differences in the prevalence and development of MS in Chinese population with abdominal obesity, which has rarely been reported.Methods
Data were obtained from the 2007-08 China National Diabetes and Metabolic Disorders Study, and participants were divided into two samples for analysis. Sample 1 consisted of 19,046 people with abdominal obesity, while sample 2 included 2,124 people meeting pre-specified requirements. Survival analysis was used to analyze the development of MS.Results
The age-standardized prevalence of MS in Chinese population with AO was 49.5%. The prevalence in males (73.7%) was significantly higher than that in females (36.9%). Males had significantly higher proportions of combinations of three or four MS components than females (36.4% vs. 30.2% and 18.4% vs. 5%, respectively). MS developed quick at first and became slow down later. Half of the participants with AO developed to MS after 3.9 years (95% CI: 3.7–4.1) from the initial metabolic abnormal component, whereas 75% developed to MS after 7.7 years (95% CI: 7.5–7.9).Conclusion
Compared with females, Chinese males with AO should receive more attention because of their higher prevalence of MS and its components, more complex and risky combinations of abnormal components, and faster development of MS. 相似文献14.
Background
Anemia is associated with poor prognosis in heart failure (HF) patients. Contributors to the risk of anemia in HF include hemodilution, renal dysfunction and inflammation. Hemoglobin levels may also be negatively affected by alterations in stress regulatory systems. Therefore, psychological distress characterized by such alterations may adversely affect hemoglobin in HF. The association between hemoglobin and Type D personality and affective symptomatology in the context of HF is poorly understood.Aim
To examine the relationship between Type D personality and affective symptomatology with hemoglobin levels at inclusion and 12-month follow-up, controlling for relevant clinical factors.Methods
Plasma levels of hemoglobin and creatinine were assessed in 264 HF patients at inclusion and at 12-month follow-up. Type D personality and affective symptomatology were assessed at inclusion.Results
At inclusion, hemoglobin levels were similar for Type D and non-Type D HF patients (p = .23), and were moderately associated with affective symptomatology (r = –.14, p = .02). Multivariable regression showed that Type D personality (β = –.15; p = .02), was independently associated with future hemoglobin levels, while controlling for renal dysfunction, gender, NYHA class, time since diagnosis, BMI, the use of angiotensin-related medication, and levels of affective symptomatology. Change in renal function was associated with Type D personality (β = .20) and hemoglobin at 12 months (β = –.25). Sobel mediation analysis showed significant partial mediation of the Type D – hemoglobin association by renal function deterioration (p = .01). Anemia prevalence increased over time, especially in Type D patients. Female gender, poorer baseline renal function, deterioration of renal function and a longer HF history predicted the observed increase in anemia prevalence over time, while higher baseline hemoglobin was protective.Conclusion
Type D personality, but not affective symptomatology, was associated with reduced future hemoglobin levels, independent of clinical factors. The relation between Type D personality and future hemoglobin levels was mediated by renal function deterioration. 相似文献15.
Lene Fogt Lundbo Louise Nygaard Clausen Nina Weis Kristian Sch?nning Lene Rosen?rn Thomas Benfield Peer Brehm Christensen 《PloS one》2014,9(12)
Objective
Liver fibrosis has been associated with hepatitis C virus (HCV) genotype and genetic variation near the interleukin 28B (IL28B) gene, but the relative contribution is unknown. We aimed to investigate the relation between HCV genotypes, IL28B and development of liver stiffness.Patients and Methods
This cross-sectional study consists of 369 patients with chronic hepatitis C (CHC). Liver stiffness was evaluated using transient elastograhy (TE). Factors associated with development of liver fibrosis were identified by logistic regression analysis.Results
We identified 369 patients with CHC. 235 were male, 297 Caucasians, and 223 had been exposed to HCV through intravenous drug use. The overall median TE value was 7.4 kPa (interquartile range (IQR) 5.7–12.1). HCV replication was enhanced in patients carrying the IL28B CC genotype compared to TT and TC (5.8 vs. 5.4 log10 IU/mL, p = 0.03). Patients infected with HCV genotype 3 had significantly higher TE values (8.2 kPa; IQR, 5.9–14.5) compared to genotype 1 (6.9 kPa; IQR, 5.4–10.9) and 2 (6.7 kPa; IQR, 4.9–8.8) (p = 0.02). Within patients with genotype 3, IL28B CC genotype had the highest TE values (p = 0.04). However, in multivariate logistic regression, using various cut-off values for fibrosis and cirrhosis, only increasing age (odds ratio (OR) 1.09 (95% confidence interval (CI), 1.05–1.14 per year increment)), ALT (OR 1.01 (95% CI, 1.002–1.011), per unit increment) and HCV genotype 3 compared to genotype 1 (OR 2.40 (95% CI, 1.19–4.81), were consistently associated with cirrhosis (TE>17.1 kPa).Conclusions
Age, ALT and infection with HCV genotype 3 were associated with cirrhosis assessed by TE. However, IL28B genotype was not an independent predictor of fibrosis in our study. 相似文献16.
Ravi Narang Kelly Bakewell Jane Peach Sadie Clayton Martin Samuels John Alexander Warren Lenney Francis J. Gilchrist 《PloS one》2014,9(9)
Objectives
Flexible bronchoscopy with bronchoalveolar lavage (FB-BAL) is increasingly used for the microbiological confirmation of protracted bacterial bronchitis (PBB) in children with a chronic wet cough. At our centre, when performing FB-BAL for microbiological diagnosis we sample 6 lobes (including lingula) as this is known to increase the rate of culture positive procedures in children with cystic fibrosis. We investigated if this is also the case in children with PBB.Methods
We undertook a retrospective case note review of 50 children investigated for suspected PBB between May 2011 and November 2013.Results
The median (IQR) age at bronchoscopy was 2.9 (1.7–4.4) years and the median (IQR) duration of cough was 11 (8.0–14) months. Positive cultures were obtained from 41/50 (82%) and 16 (39%) of these patients isolated ≥2 organisms. The commonest organisms isolated were Haemophilus influenzae (25 patients), Moraxella catarrhalis (14 patients), Staphylococcus aureus (11 patients) and Streptococcus pneumoniae (8 patients). If only one lobe had been sampled (as per the European Respiratory Society guidance) 17 different organisms would have been missed in 15 patients, 8 of whom would have had no organism cultured at all. The FB-BAL culture results led to an antibiotic other than co-amoxiclav being prescribed in 17/41 (41%) patients.Conclusions
Bacterial distribution in the lungs of children with PBB is heterogeneous and organisms may therefore be missed if only one lobe is sampled at FB-BAL. Positive FB-BAL results are useful in children with PBB and can influence treatment. 相似文献17.
Michael Dalager-Pedersen Mette S?gaard Henrik C. Sch?nheyder Reimar W. Thomsen John A. Baron Henrik Nielsen 《PloS one》2014,9(1)
Background
Infections may increase the risk for venous thromboembolism (VTE), but little is known about VTE risk associated with community-acquired bacteraemia (CAB). We examined the risk for VTE within one year of CAB in comparison to that in matched controls.Methods
We conducted a population-based cohort study in North Denmark 1992–2011, using data from high-quality health-care databases. We included 4,213 adult CAB patients who had positive blood cultures drawn on the day of hospital admission, 20,084 matched hospitalised controls admitted for other acute medical illness, and 41,121 matched controls from the general population. We computed 0–90 and 91–365 day absolute risks for hospital-diagnosed VTE and used regression analyses with adjustment for confounding factors to compare the risk for VTE in bacteraemia patients and controls.Results
Among CAB patients, 1.1% experienced VTE within 90 days of admission and 0.5% during 91–365 days after admission. The adjusted 90-day odds ratio (OR) for VTE was 1.9 (95% CI 1.4–2.7) compared with hospitalised controls, and 23.4 (95% CI 12.9–42.6) compared with population controls. During 91–365 days after CAB admission, the VTE risk remained moderately increased (adjusted hazard ratio vs. hospitalised controls, 1.4; 95% CI 0.8–2.5, and vs. population controls, 1.9; 95% CI 1.0–3.3). Compared to hospitalised controls, the 90-day VTE risk increase was greater for Gram-positive infection (adjusted OR 2.5; 95% CI 1.6–4.1) than for Gram-negative infection (adjusted OR, 1.2; 95% CI 0.7–2.1), partly due to a high risk after Staphylococcus aureus infection (3.6%).Conclusion
The risk for VTE is substantially increased within 90 days after community-acquired bacteraemia when compared to hospitalised controls and population controls. However, the absolute risk of VTE following CAB is low. 相似文献18.
Background and Aims
Many aquatic species with stylar polymorphisms have the capacity for clonal and sexual reproduction and are sensitive to the balance of the two reproductive modes when there are a limited number of mating morphs within a population. This study asked how the clonal and sexual reproductive modes perform in populations that contain only a single morph and where fitness gain through sexual reproduction is rare. In clonal aquatic Nymphoides montana, polymorphic populations normally contain two mating morphs in equal frequencies. Populations are sexually fertile and appear to be maintained by pollen transfer between the two partners. However, in a monomorphic population of N. montana where mating opportunities are unavailable, female and male function is impaired and clonality maintains the population. Here, the consequences of intraspecific variation in sexuality were explored between monomorphic and polymorphic N. montana populations in eastern Australia.Methods
Comparative measurements of male and female fertility, total dry mass and genotypic diversity using ISSR markers were made between populations with variable sexuality.Key Results and Conclusions
Very few seeds were produced in the monomorphic population under natural and glasshouse conditions due to dysfunctional pollen and ovules. Stigma–anther separation was minimal in the monomorphic population, which may be a consequence of the relaxed selective pressures that regulate the maintenance of sexual function. However, clonal reproduction was favoured at the expense of sexual reproduction in the monomorphic population; this may facilitate the establishment of sterility throughout the population via resource reallocation or pleiotropic effects. The ISSR results showed that the monomorphic population was one large, single genotype, unlike the multi-genotypic fertile polymorphic populations. Evolutionary loss of sex in a clonal population in which a mating morph is absent was evident; under these conditions clonal growth may assure reproduction and expand the population via spreading stolons. 相似文献19.
Sung-Min Kim Junwoo Park Sun Hee Kim Su-Yeon Park Jee Young Kim Jung-Joon Sung Kyung Seok Park Kwang-Woo Lee 《PloS one》2013,8(12)
Background and Objective
Neuromyelitis optica (NMO) is an inflammatory demyelinating disorder of the central nervous system with a relapsing and remitting course. We aimed to identify factors associated with the time to next attack, including the effect of the natural disease course and the diverse treatment regimens, by applying a longitudinal statistical analysis to the individual attacks of each patient.Methods
In total, 184 acute attacks among 58 patients with either NMO or NMO spectrum disorder with anti-aquaporin-4 antibody were assessed retrospectively. Patient demographics, clinical characteristics at each attack, and type of treatment during inter-attack periods were assessed. The dependent variable was defined as the time from each attack to the next attack (inter-attack interval). An exponential accelerated failure time model with shared gamma frailty was adapted for statistical analysis.Results
A multivariable analysis revealed that the time from each attack to the next attack in NMO increased independently by 1.31 times (95% confidence interval (CI), 1.02–1.67; p = 0.035) with each additional cumulative attack experienced, by 5.34 times (95% CI, 1.57–18.13; p = 0.007) with combined azathioprine treatment and continued oral prednisolone, and by 4.26 times (95% CI, 1.09–16.61; p = 0.037) with rituximab treatment.Conclusion
The time to next attack in NMO can increase naturally in the later stages of the disease as the number of cumulative attacks increases. Nevertheless, both combined azathioprine treatment with continued oral prednisolone and rituximab treatment were also associated with a longer time to next attack, independently of the natural disease course of NMO. 相似文献20.
Jaishri Mehraj Manas K. Akmatov Julia Str?mpl Anja Gatzemeier Franziska Layer Guido Werner Dietmar H. Pieper Eva Medina Wolfgang Witte Frank Pessler Gérard Krause 《PloS one》2014,9(9)