bluuebunny/crossref_metadata_2025_split huggingface dataset:
Grains of connectivity: analysis at multiple spatial scales in landscape genetics
Authors: GALPERN PAUL , MANSEAU MICHELINE , WILSON PAUL 
Published: June 2012

AbstractLandscape genetic analyses are typically conducted at one spatial scale. Considering multiple scales may be essential for identifying landscape features influencing gene flow. We examined landscape connectivity for woodland caribou (Rangifer tarandus caribou) at multiple spatial scales using a new approach based on landscape graphs that creates a Voronoi tessellation of the landscape. To illustrate the potential of the method, we generated five resistance surfaces to explain how landscape pattern may influence gene flow across the range of this population. We tested each resistance surface using a raster at the spatial grain of available landscape data (200 m grid squares). We then used our method to produce up to 127 additional grains for each resistance surface. We applied a causal modelling framework with partial Mantel tests, where evidence of landscape resistance is tested against an alternative hypothesis of isolation‐by‐distance, and found statistically significant support for landscape resistance to gene flow in 89 of the 507 spatial grains examined. We found evidence that major roads as well as the cumulative effects of natural and anthropogenic disturbance may be contributing to the genetic structure. Using only the original grid surface yielded no evidence for landscape resistance to gene flow. Our results show that using multiple spatial grains can reveal landscape influences on genetic structure that may be overlooked with a single grain, and suggest that coarsening the grain of landcover data may be appropriate for highly mobile species. We discuss how grains of connectivity and related analyses have potential landscape genetic applications in a broad range of systems.
A Bacillus subtilis sensor kinase involved in triggering biofilm formation on the roots of tomato plants
Authors: Chen Yun , Cao Shugeng , Chai Yunrong , Clardy Jon , Kolter Roberto , Guo Jian‐hua , Losick Richard 
Published: June 2012

SummaryThe soil bacterium Bacillus subtilis is widely used in agriculture as a biocontrol agent able to protect plants from a variety of pathogens. Protection is thought to involve the formation of bacterial communities – biofilms – on the roots of the plants. Here we used confocal microscopy to visualize biofilms on the surface of the roots of tomato seedlings and demonstrated that biofilm formation requires genes governing the production of the extracellular matrix that holds cells together. We further show that biofilm formation was dependent on the sensor histidine kinase KinD and in particular on an extracellular CACHE domain implicated in small molecule sensing. Finally, we report that exudates of tomato roots strongly stimulated biofilm formation ex planta and that an abundant small molecule in the exudates, L‐malic acid, was able to stimulate biofilm formation at high concentrations in a manner that depended on the KinD CACHE domain. We propose that small signalling molecules released by the roots of tomato plants are directly or indirectly recognized by KinD, triggering biofilm formation.
The nitric oxide reductase of enterohaemorrhagic Escherichia coli plays an important role for the survival within macrophages
Authors: Shimizu Takeshi , Tsutsuki Hiroyasu , Matsumoto Akio , Nakaya Haruaki , Noda Masatoshi 
Published: June 2012

SummaryIn enterohaemorrhagic Escherichia coli (EHEC) O157, there are two types of anaerobic nitric oxide (NO) reductase genes, an intact gene (norV) and a 204 bp deletion gene (norVs). Epidemiological analysis has revealed that norV‐type EHEC are more virulent than norVs‐type EHEC. Thus, to reveal the role of NO reductase during EHEC infection, we constructed isogenic norV‐type and norVs‐type EHEC mutant strains. Under anaerobic conditions, the norV‐type EHEC was protected from NO‐mediated growth inhibition, while the norVs‐type EHEC mutant strain was not, suggesting that NorV of EHEC was effective in the anaerobic detoxification. We then investigated the role of NO reductase within macrophages. The norV‐type EHEC produced a lower NO level within macrophages compared with the norVs‐type EHEC. Moreover, the norV‐type EHEC resulted in higher levels of Shiga toxin 2 (Stx2) within macrophages compared with the norVs‐type EHEC. Finally, the norV‐type EHEC showed a better level of survival than the norVs‐type EHEC. These data suggest that the intact norV gene plays an important role for the survival of EHEC within macrophages, and is a direct virulence determinant of EHEC.
Downregulation of TLR‐7 receptor in hepatic and non‐hepatic patients with lichen planus
Authors: El Tawdy Amira , Rashed Laila 
Published: June 2012

AbstractBackground  Lichen planus (LP) is an inflammatory disease of the skin and oral mucosa. The association of LP and chronic hepatitis C virus (HCV) is well established, with variable prevalence rates among different populations. Toll‐like receptors (TLRs) are key regulators of both the innate response and the adaptive response. However, TLRs also interact with endogenous ligands released by necrotic cells, and this process can intensify autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus.Objective  To investigate the role of Toll‐like receptor‐7 (TLR‐7) in LP through the detection of TLR‐7 protein, and to compare between the expression of TLR‐7 protein in HCV‐positive and HCV‐negative patients with LP.Materials and methods  The study included 20 skin biopsies from patients with LP and 10 control biopsies. TLR‐7 protein was detected by Western blot analysis. Detection of HCV‐specific antibodies in the patient serum was done using ELISA technique.Results  Our analysis revealed a significantly lower level of TLR‐7 protein in all the LP skin biopsies compared with controls. The expression showed no difference between HCV‐positive and HCV‐negative patients.Conclusion  We concluded that TLR‐7 abnormal expression in LP may have an impact on the pathogenesis of the disease. TLR‐7 receptor and HCV relationship in patients with LP could not be confirmed by this study.
Detection of human papillomavirus type 16 in Bowen’s carcinoma of the toe
Authors: Mii Sumiyuki , Niiyama Shiro , Takasu Hiroshi , Kosaka Shinichiro , Hara Kazuya , Kitasato Hidero , Sato Yuichi , Katsuoka Kensei 
Published: June 2012

AbstractBackground  Human papillomavirus (HPV) is known to cause cervical cancer. Because it has been detected in lesions of Bowenoid papulosis, Bowen’s disease, and Bowen’s carcinoma, HPV infection has been implicated in the pathogenesis of these diseases.Methods  A 44‐year‐old man was diagnosed clinicopathologically with Bowen’s carcinoma of the right great toe. He developed multiple organ metastases and died. We examined HPV DNA in skin biopsy specimens from the primary and skin metastatic lesions by polymerase chain reaction (PCR) and in situ hybridization (ISH). The PCR assay was carried out using primer sets specifically designed for detecting the E6 and E7 genes of the HPV types associated with malignancy. Purified and cloned PCR products were subjected to DNA sequence analysis. The ISH studies used INFORM® HPV III probes.Results  We found HPV DNA in specimens from both the primary and the skin metastatic lesions. DNA sequencing detected HPV type 16. We compared the base sequences of viral DNA from the primary and metastatic lesions. Point mutations of the base sequences of the E6 and E7 genes were observed in viral DNA from metastases but not in that from primary lesions. The E6 gene had mutated from G to A in the 383rd base sequence, causing a Glu‐to‐Lys amino acid change. Results of ISH showed punctuate signals in the nuclei of tumor cells.Conclusions  We suspect an association between HPV 16 infection and the development of this malignant occurrence.
Risk factors for surgical site infection after dermatological surgery
Authors: Heal Clare F. , Buettner Petra G. , Drobetz Herwig 
Published: June 2012

AbstractObjectives  Surgical site infection (SSI) following minor surgery contributes to patient morbidity and compromises cosmetic outcomes. The purpose of this study was to determine the incidence of and risk factors for SSI after dermatological surgery in general practice.Methods  A prospective, observational study which assessed infection among 972 patients was conducted in regional north Queensland, Australia. Consecutive patients presenting for minor skin excisions were invited to participate. Wounds were assessed for SSI at the time of removal of sutures.Results  Infection occurred in 85 of the 972 excisions; thus, the overall incidence of infection was 8.7% (95% confidence interval 6.5–11.0). Excisions in the upper (P < 0.001) or lower (P < 0.001) extremities, excisions of basal cell carcinoma (BCC) (P = 0.001) or squamous cell carcinoma (SCC) (P = 0.001), and re‐excision of skin cancer were found to be independent risk factors for wound infection. The length of the excision (P < 0.001) and the patient’s status as an ex‐smoker (P = 0.019) were additional independent risk factors for infection. Diabetes was not found to be an independent risk factor for infection (P = 0.891).Conclusions  Prophylactic antibiotics are probably prescribed excessively or inappropriately for dermatological surgery, and overall we wish to discourage their use. The results of this study may encourage the more judicial use of prophylactic antibiotics by defining high‐risk procedures, such as excisions from the extremities, excision of BCC or SCC, and larger excisions, and patients who are at high risk for infection, such as ex‐smokers.
Itch pathophysiology may differ among ethnic groups
Authors: Hajdarbegovic Enes , Thio Hok Bing 
Published: June 2012

AbstractThe prevalence of itch is higher in individuals with darker skin types. In this paper, we review the systems involved in the physiology of itch and how they may differ across the races. Current data point out that the differences may be explained by barrier function, mast cell physiology, and itch receptor polymorphisms.
Varicella‐zoster virus (VZV) and alpha 1 antitrypsin: a fatal outcome in a patient affected by endemic pemphigus foliaceus
Authors: Abreu Velez Ana Maria , Smoller Bruce R. , Gao Weiqing , Grossniklaus Hans E. , Jiao Zhe , Arias Luis F. , Dudley Samuel C. , Howard Michael S. 
Published: June 2012

AbstractBackground  Herpes virus infections are well known infectious complications of pemphigus and bullous pemphigoid. We describe pathologic findings utilizing autopsy tissue from several organs from a patient affected by a new variant of endemic pemphigus in El Bagre, Colombia, South America.Case report  We describe a patient by a new variant of endemic pemphigus foliaceus from El Bagre that was receiving high‐dosage immunosuppressants when hospitalized and died suddenly following contact with a second patient affected by chicken pox.Materials and methods  We performed studies utilizing hematoxylin and eosin, immunohistochemistry, and direct immunofluorescence techniques on tissues from several organs.Results  We detected the presence of varicella zoster virus, as well as strong positivity for α‐1 antitrypsin in the heart, kidneys, spleen, liver, skin, brain, lungs, pancreas, small and large intestines, and skeletal muscle. In regard to structural damage in the kidney and heart, we believe the observed damage is associated with the presence of autoantibodies to these organs, since both of them are rich in plakins and El Bagre‐EPF patients present significant antibodies to plakin molecules.Conclusion  In patients with endemic pemphigus foliaceus, we recommend complete isolation of the patient when receiving high dosages of systemic immunosuppressive agents. We further suggest the clinical possibility of a synergistic, fatal interaction between active pemphigus foliaceus, varicella zoster virus, herpes simplex virus, immunosuppressive agents, and a systemic activation of α‐1 antitrypsin. Thus, we suggest adequate bed spacing, barrier nursing, and preventative testing for α‐1 antitrypsin activation are warranted in these patients to address these complications.
Identification of a novel HLA‐B*46 allele, B*46:01:07, in a Chinese individual
Authors: Jiao S.‐X. , Liu X.‐H. , Chi X.‐Y. , Zhao L. , Feng Z.‐H. 
Published: June 2012

AbstractThe novel allele B*46:01:07 was identified in a Chinese individual by sequence‐based typing.
Maternal and foetal effects of remifentanil for general anaesthesia in parturients undergoing caesarean section: a systematic review and meta‐analysis
Authors: HEESEN M. , KLÖHR S. , HOFMANN T. , ROSSAINT R. , DEVROE S. , STRAUBE S. , VAN DE VELDE M. 
Published: June 2012

BackgroundRemifentanil has been suggested for the induction of general anaesthesia for caesarean section. We aimed to define remifentanil effects on maternal stress response as well as neonatal effects.MethodsRelevant articles were retrieved by a systematic literature search. Randomized, controlled trials comparing remifentanil use before delivery with placebo were selected. Maternal outcome parameters were blood pressure and heart rate; neonatal effects included the need for mask ventilation and intubation, base excess, pH values, Apgar < 7 at 1 and 5 min. The random effects model was used for meta‐analysis; risk ratio or weighted mean difference (WMD) and 95% confidence interval (95% CI) were calculated.ResultsFive articles including 186 patients were identified. Highest and lowest systolic blood pressure were significantly lower in the remifentanil group (WMD: −29.98, −50.90 to −9.07 mmHg, 95% CI; P = 0.005; and WMD: −12.46, −18.21 to −6.71 mmHg, 95% CI; P < 0.0001), the lowest heart rate was significantly lower after remifentanil treatment (WMD: −8.22, −11.67 to −4.78, 95% CI; P < 0.00001). Base excess was significantly higher in infants of remifentanil‐treated mothers (WMD: 1.15, −0.27 to 2.03, 95% CI; P = 0.01); pH was also higher in the remifentanil group, but significance was missed (P = 0.07). No differences were observed for Apgar values or the need of airway assist.ConclusionRemifentanil was found to attenuate the maternal circulatory response to intubation and surgery. Higher base excess and pH suggest a beneficial effect on the neonatal acid‐base status. A trial with adequate power is warranted that addresses neonatal side‐effects of remifentanil.
Estimating fluctuating selection in age‐structured populations
Authors: ENGEN S. , SÆTHER B.‐E. , KVALNES T. , JENSEN H. 
Published: June 2012

AbstractIn age‐structured populations, viability and fecundity selection of varying strength may occur in different age classes. On the basis of an original idea by Fisher of weighting individuals by their reproductive value, we show that the combined effect of selection on traits at different ages acts through the individual reproductive value defined as the stochastic contribution of an individual to the total reproductive value of the population the following year. The selection differential is a weighted sum of age‐specific differentials that are the covariances between the phenotype and the age‐specific relative fitness defined by the individual reproductive value. This enables estimation of weak selection on a multivariate quantitative character in populations with no density regulation by combinations of age‐specific linear regressions of individual reproductive values on the traits. Demographic stochasticity produces random variation in fitness components in finite samples of individuals and affects the statistical inference of the temporal average directional selection as well as the magnitude of fluctuating selection. Uncertainties in parameter estimates and test power depend strongly on the demographic stochasticity. Large demographic variance results in large uncertainties in yearly estimates of selection that complicates detection of significant fluctuating selection. The method is illustrated by an analysis of age‐specific selection in house sparrows on a fitness‐related two‐dimensional morphological trait, tarsus length and body mass of fledglings.
Erodium maritimum (Geraniaceae), a species with an uneven and fragmented distribution along the Western Mediterranean and European Atlantic coasts, has a weak genetic structure
Authors: Alarcón M. L. , Vargas P. , Aldasoro J. J. 
Published: June 2012

AbstractErodium maritimum L. is an annual species presenting heterogeneous, sometimes very small, and distant populations, distributed along a discontinuous coastal strip of the European Atlantic and the central and western Mediterranean basin. The aim of this study is to investigate genetic variation and geographic structure changes across its large distribution. Fourteen populations of E. maritimum were studied using AFLP fingerprints, together with their population sizes, reproductive systems and flower visitors. AFLP markers revealed the genetic structure of the species to be weak. Many individuals from one population clustered together with those of other populations, showing a high degree of genetic admixture. Despite having a self‐compatible reproductive system, populations (especially the largest ones) showed high levels of genetic polymorphism, and the majority of genetic variation was contained within populations. The low genetic structure suggests high levels of gene flow, which might be explained through the dispersability of the species’ fruits. Finally, recommendations are provided for management strategies to facilitate the conservation of this endangered species.
Interactions Among Female Guppies (Poecilia reticulata) Affect Growth and Reproduction
Authors: Borg Åsa A. , Åsmul Tommy , Bolstad Geir H. , Viken Åslaug , Berglund Anders , Rosenqvist Gunilla 
Published: June 2012

AbstractCompetition among females over resources may have consequences for their resource budgets and thereby the resource allocation between growth and reproduction. In addition, the consequences of female–female interactions may differ for dominant and subordinate individuals, with the dominant ones being at an advantage. In this study, we investigated the consequences of female–female competition in guppies by manipulating the competitive environment of females. We found that large guppy females dominated smaller females and that interactions between females likely are costly because females exposed to competition grew less. These females compensated by growing at a higher rate when no longer subjected to competition. The higher growth rate might in turn be the cause of the reduced reproductive effort in the more competitive treatments. Furthermore, interactions were more costly for females when they were in the subordinate role than in the dominant role, because the reduction in growth and reproductive effort was highest in females exposed to larger competitors. Whether there was a differential allocation of resources into growth and reproduction depending on dominance status needs further investigation. However, in general, smaller females had a higher growth rate than larger females, independent of competitive level. We also found a negative relationship between reproduction and growth in all treatments, indicating a cost of reproduction.
Frost Hardiness Expression and Characterisation in Wheat at Ear Emergence
Authors: Al‐Issawi M. , Rihan H. Z. , El‐Sarkassy N. , Fuller M. P. 
Published: June 2012

AbstractOccasionally, wheat can be exposed to overnight freezing temperatures whilst it is in the early reproductive stage and considerable frost damage can occur. In the vegetative stage, full expression of frost tolerance genes can be gained when plants are exposed to acclimation temperatures (4 °C). Paradoxically, wheat during flowering has limited or no ability to effectively acclimate or re‐acclimate and it demonstrates frost sensitivity during this stage. Using a combined approach involving infrared thermography and molecular analysis, the causes and effects of frost‐induced damage to wheat during ear emergence were investigated. It was demonstrated that frost damage only occurs to wheat ears if the temperature falls below −5 °C but some ears, and some spikelets on frozen ears do not freeze but supercool and escape freezing. In whole plant freezing experiments, spikelets showed both complete and partial sterility upon maturation and this was linked to parallel infrared observation of detached ears showing full or partial freezing of spikelets. It was hypothesised that wherever spikelet freezing occurred the spikelet was sterile and grain production per ear was drastically reduced, and in contrary, spikelet survival was as a result of supercooling. Molecular analysis of the upregulation of Cbf14 showed that as ear emergence progressed the ability to induce Cbf14 decreased but at early stages of ear emergence Cbf14 was able to be induced by exposure to acclimating temperatures (4 °C). The hypothesis that the lack of the ear to acclimate is because of the incapability to induce the CBF transcription factor was only partially upheld in this investigation. Further work is needed to elucidate more precisely the molecular incompetency for the acclimation of wheat during ear emergence.
Developmental Dynamics and Early Growth Vigour in Rice 2. Modelling Genetic Diversity Using Ecomeristem
Authors: Luquet D. , Soulié J. C. , Rebolledo M. C. , Rouan L. , Clément‐Vidal A. , Dingkuhn M. 
Published: June 2012

AbstractEarly vigour is an important objective in rice breeding. A previous study reported strong positive effects of development rate (DR, 1/phyllochron) on early growth vigour in two rice panels. This study provided a model‐based analysis of DR effects on rice early vigour and underlying source–sink processes during exponential growth, using Ecomeristem model. Relevant model parameters were fitted to panel observations, and their effect on early vigour was quantified. A sensitivity analysis was performed to quantify the impact of model parameters on simulation outputs. The simulated behaviour of a population of virtual genotypes defined by the combination of model parameter values was compared with that of diversity panel. Finally, a simulation experiment was conducted to analyse source–sink adjustments constituting early vigour across a range of DR. Parameters governing structural development, particularly DR, had greater impact on vigour than parameters for resource acquisition. High DR was associated with rapid dry weight accumulation and low transitory carbohydrate reserves in both real and virtual populations. Genotypic DR is thus a major driver of early vigour in rice under stress‐free conditions. To evaluate traits contributing to vigour, the capacity of crop models to simulate interactions between structural development and resource acquisition must be improved.
Simple method of <100% oxygen resuscitation for preterm infants
Authors: Nuntnarumit Pracha , Phummaphuti Piyawan , Tangnoo Archara 
Published: June 2012

AbstractBackground:  The aim of this study was to determine the feasibility of 50–60% oxygen resuscitation by a simple method using a self‐inflation bag without oxygen reservoir for positive pressure ventilation (PPV) or using a constant distance and flow rate for blow‐by oxygen.Methods:  Newborn infants ≤35 weeks gestational age were eligible. Infants requiring PPV were initiated with bag‐mask PPV without oxygen reservoir. Nearly 100% oxygen was given by attaching oxygen reservoir if heart rate < 100 beats/min after PPV for 90 s or SpO2 < 75% at 3 min. For those requiring blow‐by oxygen, oxygen flow 5 L/min via facemask was given 5 cm from the nose. Almost 100% oxygen was given by close‐fitting facemask to nose if SpO2 < 80% at 5 min.Results:  Ninety‐one infants were eligible; 67 of them required resuscitation. Thirty‐five infants required PPV; 27 (77.1%) responded to bag‐mask PPV without oxygen reservoir. For 32 infants requiring blow‐by oxygen, 28 (87.5%) reached the targeted SpO2. No significant differences in clinical outcomes were observed between responders and non‐responders.Conclusions:  The technique of <100% oxygen supplementation was effective for preterm newborn resuscitation with a high success rate. This technique may be useful for a limited‐resource setting.