bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence and genotype distribution of human papillomavirus infection of the cervix in Spain: The CLEOPATRE study
Authors: Castellsagué Xavier , Iftner Thomas , Roura Esther , Vidart José Antonio , Kjaer Susanne K. , Bosch F. Xavier , Muñoz Nubia , Palacios Santiago , Rodriguez Maria San Martin , Serradell Laurence , Torcel‐Pagnon Laurence , Cortes Javier ,   for the CLEOPATRE Spain Study Group
Published: April 2012

Human papillomavirus (HPV) infection is a necessary cause of cervical cancer. The aim of this study was to estimate the prevalence of cervical HPV infection and HPV type‐specific distribution among women attending cervical cancer screening in Spain during 2007 and 2008. Women aged 18–65 years were recruited according to an age‐stratified sampling method. Liquid‐based cervical samples were collected and analyzed for cytology, HPV detection, and genotyping. HPV genotyping was determined using the INNO‐LiPA HPV Genotyping Extra Reverse Hybridization Line Probe Assay. Prevalence estimates were age‐standardized using 2001 Spanish census data. The present study included 3,261 women. Age‐standardized HC2‐based HPV prevalence was 14.3% (95% CI, 13.1–15.5) among women aged 18–65 years, and 28.8% (26.6–31.1) among women aged 18–25 years. High‐risk HPV types were detected in 12.2% (95% CI, 11.1–13.4) of HPV‐tested women, representing 84.0% of HPV‐positive samples. Multiple infections were present in 4.1% (95% CI, 3.4–4.8) of HPV‐tested women (25.0% of HPV‐positive samples). The most common high‐risk HPV‐types among HPV‐tested women were 16 (2.9%), 52 (1.8%), 51 (1.6%), 31 (1.3%), and 66 (1.2%). HPV‐type 16 was present in 16.9% of HPV‐positive samples. One or more of the HPV vaccine types 6/11/16/18 were detected in 3.8% of HPV‐tested women (22.1% of HPV‐positive samples). Though not a true population‐based survey, this study provides valuable baseline data for future assessment of the impact of current HPV vaccination programs in Spain. The high prevalence of HPV infection among young women may reflect recent changes in sexual behavior. J. Med. Virol. 84:947–956, 2012. © 2012 Wiley Periodicals, Inc.
Early human enterovirus infections in healthy Swedish children participating in the PRODIA pilot study
Authors: Simonen‐Tikka Marja‐Leena , Hiekka Anna‐Kaisa , Klemola Päivi , Poussa Tuija , Ludvigsson Johnny , Korpela Riitta , Vaarala Outi , Roivainen Merja
Published: April 2012

Human enteroviruses (HEV) are common, especially in childhood and during the enterovirus season, causing mainly asymptomatic infections but also mild and severe illnesses. Numerous studies have shown the association between HEV infections and type 1 diabetes. Here, the prevalence of HEV infections was studied in healthy Swedish children with increased HLA‐associated risk for type 1 diabetes participating in the PRODIA pilot study in which children were randomized to receive probiotics or placebo during the first 6 months of life. Stool specimens collected from 197 children in every 3 months from the age of 3 to 24 months were screened for HEV using traditional viral culturing method and identified with reverse transcriptase polymerase chain reaction (RT‐PCR) and sequencing of the partial VP1 coding part of the viral genome. Altogether 4.8% (52/1,094) of the specimens were HEV‐positive and 22.3% (44/197) of the children excreted HEV during the follow‐up. HEV‐A and HEV‐B were present in 2.1 and 2.7% of the specimens, respectively. HEV‐C and HEV‐D viruses were not detected. In total, 17 different HEV serotypes were detected and the most common findings were CV‐A9 (13.5%), CV‐A16 (11.5%), and CV‐A2 (9.6%). The majority of the infections (92.3%) were during the enterovirus season extending from July to December. Probiotic treatment did not affect significantly the risk of HEV infections during the 2‐year follow‐up although a trend for transient decrease for HEV positivity (HEV‐A and/or HEV‐B) by the age of 12 months was observed in children who received probiotics [OR 0.40; 95% confidence interval 0.15 to 1.08; P‐value 0.071, generalized estimating (GEE) analysis]. According to the results, HEV‐A findings were nearly as common as HEV‐B findings among the healthy children participating in this study. Also it was shown that serotypes belonging to HEV‐A species can be detected by means of viral culturing. J. Med. Virol. 84:923–930, 2012. © 2012 Wiley Periodicals, Inc.
Improved quantitative PCR protocols for adenovirus and CMV with an internal inhibition control system and automated nucleic acid isolation
Authors: Henke‐Gendo C. , Ganzenmueller T. , Kluba J. , Harste G. , Raggub L. , Heim A.
Published: April 2012

With the establishment of routine virus load (DNAemia) screening for Human adenovirus (HAdV) and Cytomegalovirus (CMV) in post‐transplant care quality standards for quantitative PCR‐assays are increasing. Established real‐time PCR assays were improved with a fully automated DNA‐extraction and with a competitive internal control DNA packaged into a lambda phage which serves as an extraction and amplification control in each sample. HAdV and CMV DNA were detected and quantified simultaneously in various types of diagnostic samples like blood, feces or respiratory tract materials. Inhibition was observed in 0.33–0.66% of over 14,000 diagnostic samples, an infrequent but nevertheless not negligible event, which is observed mainly in stool samples. CMV viral load in broncho‐alveolar lavage fluid (BALF) ranged between positive but below the quantitation limit of 1,000 copies/ml up to 1.8 × 107 copies/ml with a median of 6.0 × 103 copies/ml. Forty‐one (4.7%) BALF samples had a viral load above 5.0 × 105 copies/ml, which was proposed as a threshold for the diagnosis of pneumonia. HAdV viral loads ranged between positive but below the quantitation limit of 1,000 copies/ml to a very high concentration of 1.3 × 1011 copies/ml in stool and BALF samples. A HAdV‐DNAemia of >104 copies/ml was found only in patients with stool viral load of above 105 copies/ml. These data support the hypothesis that quantitation in diagnostic materials other than blood may give valuable diagnostic information and that further evaluation of this approach is reasonable. J. Med. Virol. 84:890–896, 2012. © 2012 Wiley Periodicals, Inc.
Human parvovirus B19 surveillance in patients with rash and fever from Belarus
Authors: Yermalovich Marina A. , Hübschen Judith M. , Semeiko Galina V. , Samoilovich Elena O. , Muller Claude P.
Published: April 2012

Human parvovirus B19 (B19V) infection in immunocompetent patients usually has a mild clinical course, but during pregnancy it can cause serious and even fatal complications in the fetus. The most common clinical presentation of B19V infection is erythema infectiosum and in this case laboratory confirmation is required for differentiation from other exanthematous diseases. Measles and rubella negative sera collected in Belarus between 2005 and 2008 from 906 patients with a rash and fever were screened for B19V infection by ELISA. More than 35% of the samples (322/906) were positive for B19V. The proportion ranged from 10.1% in 2008 to 53.2% in 2006 when an outbreak took place in Minsk city. All B19V outbreaks and cluster cases occurred during the winter–spring period, but sporadic cases were recorded basically throughout the year. The majority of the cases (56.5%) occurred among the 2 till 10 year old children, and 27.3% of the cases were observed in adults between 19 and 53 years. All 104 B19V strains sequenced in the NS1/VP1u region belonged to genotype 1 with a maximal genetic distance of 1.75%. The two phylogenetic clusters reflected the geographic origins of the viruses within the country. Forty‐two unique nucleotide mutations as compared to sequences downloaded from GenBank were found in the VP1u and NS1 regions; most of these changes were nonsynonymous. This report highlights the importance of B19V infection in patients with a rash and fever in Belarus. J. Med. Virol. 84:973–978, 2012. © 2012 Wiley Periodicals, Inc.
Assessing risk of a short‐term antiretroviral therapy discontinuation as a read‐out of viral control in immune‐based therapy
Authors: Routy J.P. , Boulassel M.R. , Nicolette C.A. , Jacobson J.M.
Published: April 2012

Although analytical treatment interruption is used as a strategy to test immunotherapeutic agents in HIV‐infection, it may pose a risk for study participants. The potential risks of short‐term interruption of antiretroviral therapy (ART) during treatment with an autologous dendritic cell immune‐based therapy (AGS‐004‐001) were assessed using data from a subgroup of subjects in the strategies for management of antiretroviral therapy (SMART) study with matched eligibility criteria. A retrospective subgroup analysis of the SMART study population using the eligibility criteria and treatment stopping rules of AGS‐004‐001 study was analyzed. Key inclusion criteria for AGS‐004‐001 study were applied to the data collected from participants of the SMART study. There were 440 of 2,720 on the drug conservation arm and 436 of 2,752 on the viral suppression arm that matched the AGS‐004‐001 inclusion criteria and were used in the SMART subgroup analysis. In the first 16 weeks following randomization into the SMART study there were no deaths in either subgroup. There were two AIDS‐related events in the drug conservation subgroup and one in the viral suppression subgroup, making the overall risk of AIDS‐related events 2 per 100 person years (0.005%) and 1 per 100 person years (0.002%) in the two subgroups, respectively. There were 6/440 subjects (1.4%) in the drug conservation subgroup and 4/436 subjects (0.92%) in the viral suppression subgroup who experienced Grade 2 adverse events. These results demonstrated that analytical treatment interruption within the context of highly selective, closely monitored studies assessing the antiviral activity of immune‐based agents should be an acceptable strategy for at least 16 weeks. J. Med. Virol. 84:885–889, 2012. © 2012 Wiley Periodicals, Inc.
High‐resolution computed tomography analysis of the prevalence of onodi cells
Authors: Tomovic Senja , Esmaeili Azadeh , Chan Norman J. , Choudhry Osamah J. , Shukla Pratik A. , Liu James K. , Eloy Jean Anderson
Published: April 2012

Objectives/Hypothesis:

Onodi cells are the posterior‐most ethmoid air cells that lie superior to the sphenoid sinus. Identification of these cells is essential prior to endoscopic sinus and skull base surgery due to their intricate relationship with the optic nerves and carotid arteries, which may lead to deleterious complications. In this study, high‐resolution computed tomography (HRCT) scans from 170 adult‐patients were analyzed by two independent observers for the presence of Onodi cells.

Study Design:

Radiographic analysis at a tertiary care medical center.

Methods:

A retrospective analysis was performed on patients undergoing HRCT between July 2008 and September 2010. Incidence of Onodi cells and demographic data were collected.

Results:

The overall prevalence of Onodi cells in this cohort was 65.3%. Subgroup analysis based on ethnicity showed a rate of Onodi cells of 83.3% in Asians, 73.1% in whites, 57.0% in African Americans, and 62.7% in Hispanics. The prevalence of Onodi cells was not significantly different among the different ethnicities (P > .05). However, this was limited by a small sample size in some ethnic groups. Onodi cell prevalence was equivalent among males and females: 62.2% and 63.5% respectively (P > .05). Overall, our results show a greater prevalence of Onodi cells than previously reported.

Conclusions:

We found a higher prevalence of Onodi cells in our cohort than previously reported in the literature. Therefore, it is important for surgeons to anticipate the presence of these cells during endoscopic sinus and skull base procedures to prevent potential complications. Laryngoscope, 2012
The effect of alcohol abuse and alcohol withdrawal on short‐term outcomes and cost of care after head and neck cancer surgery
Authors: Genther Dane J. , Gourin Christine G.
Published: April 2012

Objectives/Hypothesis:

Alcohol abuse is associated with an increased incidence of postoperative complications in surgical patients and is a significant risk factor for the development of head and neck cancer (HNCA). We sought to determine the relationship between alcohol abuse and in‐hospital mortality, postoperative complications, length of stay, and costs in HNCA surgery.

Study Design:

Retrospective cross‐sectional study.

Methods:

Discharge data from the Nationwide Inpatient Sample for 92,312 patients aged 18 years and older who underwent an ablative procedure for a malignant oral cavity, laryngeal, hypopharyngeal, or oropharyngeal neoplasm in 2003 to 2008, were analyzed using cross‐tabulations and multivariate regression modeling.

Results:

Patients who abused alcohol were more likely to have advanced comorbidity, undergo major surgical procedures, and require medical care at another facility or home healthcare after discharge. The development of alcohol withdrawal symptoms (AWS) was associated with an increased incidence of acute medical complications (odds ratio [OR]: 5.6, P < .001) and surgical complications (OR: 2.3, P < .001). After controlling for all other variables, there was no significant association of alcohol abuse or AWS with in‐hospital mortality; however, alcohol abuse and AWS were associated with significantly increased length of hospitalization and hospital‐related costs, with AWS having the single largest impact on length of stay and costs.

Conclusions:

Alcohol withdrawal is associated with an increase in postoperative medical and surgical complications, length of hospitalization, and hospital‐related costs in HNCA surgical patients. Aggressive measures to prevent the development of AWS in patients who abuse alcohol are warranted. Laryngoscope, 2012
The physiologic impact of transnasal flexible endoscopy
Authors: Ongkasuwan Julina , Yung Katherine C. , Courey Mark S.
Published: April 2012

Objectives/Hypothesis:

Diagnostic transnasal flexible endoscopy (TNFE) is a commonly used office procedure in otolaryngology. Currently there is a paucity of data on the impact of TNFE on physiologic parameters. This is relevant with the advent of office‐based endoscopic procedures. The goal of this study is to measure the impact of topical decongestion, anesthesia, and diagnostic TNFE on vital signs: systolic blood pressure (SBP) and diastolic blood pressure (DBP), heart rate (HR), and oxygenation (O2 sat).

Study Design:

Prospective case control study, in which the patient is his/her control.

Methods:

Vital signs were obtained at baseline, immediately after the application of Neosynephrine, after the application of lidocaine, 5 minutes later, with the scope in the nasopharynx and hypopharynx, and upon completion of the procedure.

Results:

Compared to the baseline data, there was a statistically significant increase in HR after the procedure (mean change, 4.06 ± 10.15 bpm; range, −14 to 42 bpm, P = .01). There was also a change in O2 sat (mean change, 0.42% ± 1.36%; range −3% to 3%, P = .03) after the application of lidocaine. When comparing each data point to the preceding point, there was a statistically significant change in SBP with the scope in the nasopharynx (mean change, 5.34 ± 10.65 mm Hg; range, −22 to 28 mm Hg, P = .001) and in HR with the scope in the hypopharynx (mean change, 3.76 ± 6.41 bpm; range, −9 to 19 bpm, P = .0004).

Conclusions:

Diagnostic TNFE and topical lidocaine can have an impact on physiologic parameters; however, these changes are unlikely to be clinically significant.
Role of nutrition and microbiota in susceptibility to inflammatory bowel diseases
Authors: Gentschew Liljana , Ferguson Lynnette R.
Published: April 2012

Inflammatory bowel diseases (IBDs), Crohn's disease (CD), and ulcerative colitis (UC) are chronic inflammatory conditions, which are increasing in incidence, prevalence, and severity, in many countries. While there is genetic susceptibility to IBD, the probability of disease development is modified by diet, lifestyle, and endogenous factors, including the gut microbiota. For example, high intakes of mono‐ and disaccharides, and total fats consistently increases the risk developing both forms of IBD. High vegetable intake reduces the risk of UC, whereas increased fruit and/or dietary fiber intake appears protective against CD. Low levels of certain micronutrients, especially vitamin D, may increase the risk of both diseases. Dietary patterns may be even more important to disease susceptibility than the levels of individual foods or nutrients. Various dietary regimes may modify disease symptoms, in part through their actions on the host microbiota. Both probiotics and prebiotics may modulate the microflora, and reduce the likelihood of IBD regression. However, other dietary factors affect the microbiota in different ways. Distinguishing cause from effect, and characterizing the relative roles of human and microbial genes, diet, age of onset, gender, life style, smoking history, ethnic background, environmental exposures, and medications, will require innovative and internationally integrated approaches.
Combined prospective and retrospective correction to reduce motion‐induced image misalignment and geometric distortions in EPI
Authors: Ooi Melvyn B. , Muraskin Jordan , Zou Xiaowei , Thomas William J. , Krueger Sascha , Aksoy Murat , Bammer Roland , Brown Truman R.
Published: April 2012

Despite rigid‐body realignment to compensate for head motion during an echo‐planar imaging time‐series scan, nonrigid image deformations remain due to changes in the effective shim within the brain as the head moves through the B0 field. The current work presents a combined prospective/retrospective solution to reduce both rigid and nonrigid components of this motion‐related image misalignment. Prospective rigid‐body correction, where the scan‐plane orientation is dynamically updated to track with the subject's head, is performed using an active marker setup. Retrospective distortion correction is then applied to unwarp the remaining nonrigid image deformations caused by motion‐induced field changes. Distortion correction relative to a reference time‐frame does not require any additional field mapping scans or models, but rather uses the phase information from the echo‐planar imaging time‐series itself. This combined method is applied to compensate echo‐planar imaging scans of volunteers performing in‐plane and through‐plane head motions, resulting in increased image stability beyond what either prospective or retrospective rigid‐body correction alone can achieve. The combined method is also assessed in a blood oxygen level dependent functional MRI task, resulting in improved Z‐score statistics. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
An Alternative Preparation of 1‐(N,N‐Dimethylaminomethyl)‐1′‐(diphenylphosphanyl)ferrocene: Synthesis and Structural Characterization of AuI and PdII Complexes with this Hybrid Ligand
Authors: Štěpnička Petr , Zábranský Martin , Císařová Ivana
Published: April 2012

1‐(N,N‐Dimethylaminomethyl)‐1′‐(diphenylphosphanyl)ferrocene (1) was synthesized in good yield by lithiation of 1‐bromo‐1′‐(diphenylphosphanyl)ferrocene and subsequent reaction with Eschenmoser’s salt (dimethylmethylideneammonium iodide). Making use of an easily accessible, nontoxic starting material, this procedure represents a convenient alternative to the original synthetic protocol based on stepwise lithiation/functionalization of 1,1′‐bis(tributylstannyl)ferrocene and reductive amination [M. E. Wright, Organometallics 1990, 9, 853–856]. Compound 1 has typical hybrid‐donor properties. When reacted with [AuCl(tht)] (tht=tetrahydrothiophene), it afforded the expected AuI phosphane complex [AuCl(1‐κP)] (2). An attempted removal of the chloride ligand from 2 with AgClO4 produced an ill‐defined material formulated as Au(1)ClO4. The uncoordinated amine substituent reacted with traces of hydrogen chloride formed by slow decomposition typically occurring in solution. In this manner, complexes [AuCl(Ph2PfcCH2NHMe2)]Cl (3, fc=ferrocene‐1,1′‐diyl) and [AuCl(Ph2PfcCH2NHMe2)]ClO4 (4) were isolated from crystallizations experiments with 2 and Au(1)ClO4, respectively. On a larger scale, complex 3 was prepared easily from 2 and hydrogen chloride. The course of reactions between [PdCl2(cod)] (cod=cycloocta‐1,5‐diene) and 1 were found to depend on the ligand‐to‐metal ratio. Whereas the reaction with two equivalents of 1 afforded bis(phosphane) complex trans‐[PdCl2(1‐κP)2] (5), that of a Pd:P ratio 1:1 produced ligand‐bridged dimer [(μ‐1)PdCl2]2 (6). With hydrogen chloride, complex 6 reacted to afford zwitterionic complex [PdCl3(1H‐κP)] (7), which was also formed when ligand 1 and [PdCl2(cod)] were allowed to react slowly by liquid‐phase diffusion of their chloroform solutions. The compounds were characterized by spectroscopic methods (multinuclear NMR and ESI–MS), and the molecular structures of complex 2–4, 6⋅2CHCl3 and 7⋅1.5CHCl3 were determined by single‐crystal X‐ray diffraction analysis.
Relationship of non‐visualization of the fetal gallbladder and amniotic fluid digestive enzymes analysis to outcome
Authors: Dreux Sophie , Boughanim Mathias , Lepinard Catherine , Guichet Agnès , Rival Jean‐Marie , de Becdelievre Alix , Dugueperoux Ingrid , Muller Françoise
Published: April 2012

Objective

The aims of this study were evaluate the significance of non‐visualization of fetal gallbladder at routine ultrasound scan in a series of 102 cases and to determine the contribution of amniotic fluid digestive enzyme (AF‐DE) analysis towards the outcome.

Method

This is a multicenter retrospective study. Outcome of pregnancies, karyotype, and result of screening for CFTR gene mutations were known in all cases. Amniotic fluid gamma‐glutamyl‐transpeptidase and intestinal alkaline phosphatase isoenzyme were assayed.

Results

Non‐visualization of the fetal gallbladder was associated with a severe disease in 25 cases (cystic fibrosis in ten, biliary duct atresia in eight, digestive tract anomalies in six, and chromosomal anomaly in one). In the remaining 77 cases, gallbladder agenesis was diagnosed in 22, and in 55, the gallbladder was subsequently demonstrated. Before 22 weeks of gestation (n = 30), an abnormal AF‐DE pattern had a 90% sensitivity and 80% specificity in detecting cystic fibrosis or biliary duct atresia. After 22 weeks, sensitivity fell to 53%. The AF‐DE pattern was normal in 82% of gallbladder agenesis cases (benign) and in 91% of the cases where the gallbladder was subsequently detected.

Conclusion

Non‐visualization of the fetal gallbladder was associated with severe anomalies in 24% of cases. Prior to 22 weeks, determination of AF‐DE contributes to the prediction of biliary atresia or the presence of cystic fibrosis. © 2012 John Wiley & Sons, Ltd.
Discovery of epigenetic biomarkers for the noninvasive diagnosis of fetal disease
Authors: Bunce Kimberly , Chu Tianjiao , Surti Urvashi , Hogge William Allen , Peters David G.
Published: April 2012

Objectives

The primary goal of this study was to identify CpG sites in the human genome that are differentially methylated in DNA obtained from chorionic villus sampling (CVS) samples and gestational age‐matched maternal blood cell (MBC) samples.

Methods

We used the HumanMethylation27 DNA Analysis BeadChip to characterize DNA methylation in samples of CVS and MBC. We then selected a subset of differentially methylated CpG sites on chromsome 13 and subjected them to analysis by mass spectrometry using the Epityper platform.

Results

We identified 718 tissue‐specific differentially methylated regions (DMRs) between MBC and CVS; 563 of these were hypermethylated in MBC and hypomethylated in CVS, whereas 155 sites were hypomethylated in MBC and hypermethylated in CVS. Further analysis of 13 DMRs on chromosome 13 by Epityper confirmed the microarray data and provided us with additional data about the methylation patterns of surrounding CpG sites.

Conclusions

Analysis of the resulting data identified a large number of cytosine‐guanine dinucleotides that are potential biomarkers for the selective amplification of fetal DNA from maternal plasma and the subsequent noninvasive detection of trisomy 13. © 2012 John Wiley & Sons, Ltd.
Faculty as undergraduate research mentors for students of color: Taking into account the costs
Authors: Schwartz Joni
Published: April 2012

This article is based on the findings of a 2‐year study that examined the nature of effective faculty/student undergraduate research (UR) science, technology, engineering, and mathematics (STEM) relationships. The study site was a large urban public college where three fourths of all incoming freshmen receive need‐based aid; and although not a historically Black college or university (HBCU), 85% are students of color. The college offers 2‐ and 4‐year STEM degree programs. Utilizing cultural historical activity theory (CHAT) as both a theoretical and methodological framework, this phenomenological study employed semistructured interviews, written surveys, and member checking to understand four paired faculty/student UR mentoring relationships over 2 years. The findings not only concur with the bulk of UR research, indicating UR's promise for addressing the low enrollment and retention rates of students of color in the STEM disciplines but also raise issues around the emotional, financial, and professional costs to UR faculty. It is these costs that are the focus of this article that concludes with ideas, for university and college administrators and all others concerned, about on how we might support faculty in UR's crucial work toward the goal of retaining students of color in STEM. © 2012 Wiley Periodicals, Inc. Sci Ed 96:527–542, 2012
Redox of NiO thin film on YSZ (111) substrate
Authors: Xing Juanjuan , Takeguchi Masaki , Tanaka Miyoko , Nakayama Yoshiko
Published: April 2012

The effect of redox process on the microstructure and composition of NiO thin film deposited on YSZ (111) substrate at room temperature by radio frequency sputtering method was investigated by transmission electron microscopy (TEM). The orientation relationship of NiO (002) or NiO (11) plane paralleling to YSZ (11) plane with NiO [110] paralleling to YSZ [110] was observed. After reduction, Ni (11) plane paralleled to YSZ (11) or YSZ (002) plane. Both reduction and oxidation processes started at the surface. A very thin nickel oxide layer remained even after reduction, which might result from oxygen transfer from YSZ to the interface. The formation of nickel oxide clusters with voids after reoxidation was due to the imbalanced transfer between the outward nickel and inward oxygen diffusions. Copyright © 2012 John Wiley & Sons, Ltd.
Mathematical models of morphogen gradients and their effects on gene expression
Authors: Shvartsman Stanislav Y. , Baker Ruth E.
Published: April 2012

An introduction to mathematical models of pattern formation by morphogen gradients is presented, using the early embryo of the fruit fly Drosophila as the main experimental example. Analysis of morphogen gradient formation is based on the source–diffusion–degradation models and a formalism of local accumulation times. Transcriptional control by morphogens is discussed within the framework of thermodynamic site occupancy models of gene regulatory regions. WIREs Dev Biol 2012 doi: 10.1002/wdev.55

For further resources related to this article, please visit the WIREs website.
Production of leukotriene B4 by Paracoccidioides brasiliensis
Authors: Biondo Guilherme Augusto , Dias‐Melicio Luciane Alarcão , Bordon‐Graciani Ana Paula , Kurokawa Cilmery Suemi , de Campos Soares Angela Maria Victoriano
Published: April 2012

Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis, the most prevalent deep mycosis in Latin America. The production of eicosanoids during fungal infection has been associated with the biology of these microorganisms and modulation of host immune response. The aim of our study was to evaluate whether P. brasiliensis strains with high or low virulence produce leukotriene B4 (LTB4), using endogenous and/or exogenous sources of arachidonic acid (AA). Moreover, we assessed whether this fungus might use the same metabolic pathway, described for mammalian cells, that involves the lipoxygenase (LOX) enzyme. The association between the production of this eicosanoid and fungus survival and growth was also evaluated. Our results showed that P. brasiliensis, irrespective of its virulence, produces high levels of LTB4 using endogenous AA. In addition, in cultures treated with exogenous AA, LTB4 levels were significantly higher, showing that this fungus also uses exogenous sources of fatty acids. Treatment with MK886, which blocks the activity of lipoxygenase, by inhibiting five‐lipoxygenase‐activating protein (FLAP) or with nordihydroguaiaretic acid (NDGA), a non‐selective lipoxygenase inhibitor, resulted in a significant reduction in LTB4 levels, indicating that the fungus produces this eicosanoid by using the LOX pathway or an enzyme with biochemically similar function. The significant reduction in viability detected in cultures treated with these inhibitors was, however, restored by adding exogenous LTB4, confirming the role of this eicosanoid in fungus survival. Moreover, the addition of LTB4 to cultures capable of producing LTs induces fungal growth. These results provide a foundation for additional studies on the contributions of LTB4 in P. brasiliensis virulence. Copyright © 2012 John Wiley & Sons, Ltd.
Diagnostic Value of FDG‐PET/CT for Lymph Node Metastasis of Colorectal Cancer
Authors: Kwak Jae Young , Kim Jae Seung , Kim Hye Jin , Ha Hyun Kwon , Yu Chang Sik , Kim Jin Cheon
Published: April 2012

Background

Lymph node metastasis is an important prognostic factor in patients with colorectal cancer. We assessed the ability of 18F‐fluorodeoxyglucose positron emission tomography/computed tomography (FDG‐PET/CT) to diagnose lymph node metastases in colorectal cancer patients.

Methods

We retrospectively analyzed the records of 473 patients who underwent preoperative FDG‐PET/CT, followed by curative surgery for colorectal cancer. Lymph node metastases were assessed as proximal or distal, depending on their anatomical location. We analyzed the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of FDG‐PET/CT and CT for detecting lymph node metastases.

Results

In detecting proximal lymph nodes, FDG‐PET/CT had a sensitivity of 66 %, a specificity of 60 %, a PPV of 63 %, an NPV of 62 %, and an accuracy of 63 %; whereas CT had a sensitivity of 87 %, a specificity of 29 %, a PPV of 57 %, an NPV of 68 %, and an accuracy of 59 % (P = 0.245). FDG‐PET/CT and CT also showed similar accuracy in detecting distal lymph nodes (87 vs. 88 %, P = 0.620).

Conclusion

Preoperative FDG‐PET/CT and CT have comparable accuracy in detecting lymph node metastases of colorectal cancer.
Early versus Delayed Imaginal Exposure for the Treatment of Posttraumatic Stress Disorder Following Accidental Upper Extremity Injury
Authors: Weis Jo M. , Grunert Brad K. , Christianson Heidi Fowell
Published: April 2012

Background

The consequences following work-related injuries are far reaching, which are in part due to unrecognized and untreated posttraumatic stress disorder (PTSD). Imaginal exposure is a frequently used cognitive behavioral approach for the treatment of PTSD. This study examined the impact of early versus delayed treatment with imaginal exposure on amelioration of PTSD symptomatology in individuals who suffered upper extremity injuries.

Methods

Sixty individuals who suffered severe work-related injuries received standard, non-randomly assigned psychological treatment for PTSD (e.g., prolonged imaginal exposure) either early (30–60 days) or delayed (greater than 120 days) following severe work-related upper extremity injury. Nine measures of various components of PTSD symptomatology were administered at onset of treatment, end of treatment, and at 6-month follow-up evaluations.

Results

Patients showed significant treatment outcomes at all three measurement intervals in both the early and delayed groups demonstrating that Prolonged Imaginal Exposure is an appropriate treatment for persons diagnosed with PTSD. In addition, there was no difference in return to work status between the early and the delayed treatment groups. However, the early treatment group required significantly fewer treatment sessions than the delayed treatment group.

Conclusions

Results supported the utility of imaginal exposure and the need for early assessment and referral for those diagnosed with PTSD following upper extremity injuries.
Mediation analysis and categorical variables: The final frontier
Authors: Iacobucci Dawn
Published: April 2012

Many scholars are interested in understanding the process by which an independent variable affects a dependent variable, perhaps in part directly and perhaps in part indirectly, occurring through the activation of a mediator. Researchers are facile at testing for mediation when all the variables are continuous, but a definitive answer had been lacking heretofore as to how to analyze the data when the mediator or dependent variable is categorical. This paper describes the problems that arise as well as the potential solutions. In the end, a solution is recommended that is both optimal in its statistical qualities as well as practical and easily implemented: computezMediation.
Mediation analysis and categorical variables: Some further frontiers
Authors: Feinberg Fred M.
Published: April 2012

Iacobucci (2012) provides a conceptually appealing, readily implemented measure to assess mediation for a far wider range of data type combinations than traditional OLS‐based analyses permit. Here, we consider potential applications and extensions along several lines, particularly in terms of random utility models, simulation‐based estimation, and potential nonlinearities, as well as some methodological and cultural impediments.
Mediation with categorical variables compleat
Authors: Iacobucci Dawn
Published: April 2012

This rejoinder addresses the thoughtful issues raised by the commentators. We hold to the analytical solution of fitting X → M (to obtain a and sa) and X&M→ (to obtain b and sb) via regression or logistic regression, depending on whether M and Y are continuous or categorical. Then researchers compute za, zb, and ZMediation.
Matched asymptotic solutions for turbulent plumes
Authors: Candelier Fabien , Vauquelin Olivier
Published: April 2012

Recent analytical investigations have shown that the vertical evolution of turbulent plumes variables can be derived straightforwardly from the knowledge of a single function $\Gamma (z)$ (called the plume function) which is the solution of a nonlinear differential equation. This article presents matched asymptotic solutions of this equation in the cases corresponding to highly lazy or highly forced plumes. First, it is shown that, far from the source, the asymptotic expression of the plume function can be derived by means of a perturbation method based on a Padé-like approximation. The resulting outer solution is invariant under translation (with respect to the vertical coordinate) so that we are led to the classical problem concerning the location of the plume (asymptotic) virtual origin. In order to determine this virtual origin location as a function of the conditions at the source, the far-field asymptotic solution is matched to an inner expansion of the solution which is valid near the source. Comparisons between these asymptotic solutions and numerical results are finally made in order to test their validity.
First discovery of Early PalaeozoicBathysiphon(Foraminifera) – test structure and habitat of a ‘living fossil’
Authors: LANDING ED , REYES SANDRA PATRUCCO , ANDREAS AMANDA L. , BOWSER SAMUEL S.
Published: April 2012

The giant, agglutinated foraminiferanBathysiphonSars, previously Triassic–Recent, occurs in much older sedimentary rock (Early Ordovician, late early Tremadocian) of Avalonia. The genus extends back toc. 485 Ma based on its discovery in platform mudstone of the Chesley Drive Group in Cape Breton Island, Nova Scotia. Elongate (up to 60 mm), epibenthicBathysiphontubes occur in wave-rippled, green-grey mudstone with a low diversity, probably dysoxic fauna. The mudstone is coeval with and lithologically similar to the Shineton Formation in Shropshire and the Welsh Borderlands. Scanning microscopy of theBathysiphonwalls shows imbricated mica grains that parallel the long axis of the tests. The lumen has a mélange of packed sediment grains, some of which are spherical structures of siliciclastic mud studded with tetrahedral pyrite crystals. A felt-like, agglutinated test, a lumen packed with spherical structures (probable stercomata) and the domal ends of some specimens are consistent with modernBathysiphon. This report is the first time that cytoplasmic activity and stercomata formation have been used to refer fossil protists to a modern group.Bathysiphondiffers from the Cambrian foraminiferanPlatysolenitesPander, which has an open lumen without stercomata, but support a comparable, sediment deposit-feeding niche.Bathysiphonis truly a ‘living fossil’, with a mode of test construction, cytoplasmic activity that formed stercomata and a niche unchanged for almost 500 million years. Foraminiferans have not been found prior to the Cambrian Period, and the Early Cambrian appearance of agglutinated foraminiferans is part of the radiation of Phanerozoic communities.
Methane reduction and energy partitioning in goats fed two concentrations of tannin from Mimosa spp.
Authors: BHATTA R. , ENISHI O. , YABUMOTO Y. , NONAKA I. , TAKUSARI N. , HIGUCHI K. , TAJIMA K. , TAKENAKA A. , KURIHARA M.
Published: April 2012

Dietary manipulation is one promising approach to reducing methane (CH4) emissions from forage-fed ruminants. Studies were conducted to evaluate the effects of feeding two concentrations of tannins from Mimosa spp. on rumen fermentation, methanogenesis and energy partitioning in goats. Adult male goats were used in three trials where three diets with increasing concentrations of tannins (control, low-tannin and high-tannin) were fed in a switch-over design. The control diet consisted of 0·65 timothy hay, 0·20 crushed maize and 0·15 soybean meal; low- and high-tannin diets contained 0·975 and 0·950 of the control diet, respectively, mixed with 0·025 and 0·050 of a commercial compound containing tannins with mean crude protein (CP) of 147 g/kg dry matter (DM) and gross energy (GE) 19 MJ/kg DM, respectively. Total contents (DM basis) of tannins (hydrolysable and condensed) in the control, low- and high-tannin diets were 0, 2·8 and 5·6 g/kg DM, respectively. The tannin source contained 37 and 76 g/kg DM of condensed and hydrolysable tannins, respectively (DM basis). The DM (664 g/d) and GE intakes (19·0 MJ/d) were similar among diet groups. Digestibilities of all dietary components in the high-tannin diet were lower (P < 0·05) than low-tannin and control diets. The faecal energy (MJ/d) output was lowest in the control diet (3·49) and increased (P < 0·05) in tannin-fed goats (3·80; 4·87) resulting in a corresponding decrease in digestible energy (DE). Methane emission, expressed both on absolute and per unit of feed intake basis, decreased (P < 0·05) with increasing concentration of tannins in the diet. For example, CH4 energy excretion was 0·98, 0·87 and 0·76 MJ/d for goats on control, low- and high-tannin diets, respectively, whereas their corresponding values for CH4 conversion ratio were 0·079, 0·069 and 0·060 of GE intake. These results suggest that natural tannins, even at a low concentration (2·8 g/kg DM of the diet), reduce CH4 emissions, and tree leaves containing appreciable amounts of tannins may potentially be exploited as natural feed additives in ruminants.
Salivary duct carcinoma: what is already known, and can we improve survival?
Authors: Wee D T H , Thomas A A , Bradley P J
Published: April 2012

Salivary duct carcinoma is an aggressive malignancy with a high mortality rate, which phenotypically resembles high-grade breast ductal carcinoma. The parotid gland is the most common location. Standard treatment is surgery to the primary tumour together with post-operative radiotherapy. Despite this, there is a high rate of local recurrence, cervical nodal involvement and distant metastasis. Chemotherapy is currently considered only for end-stage, disseminated disease; however, current evidence indicates that chemotherapy used with radiotherapy may result in improved disease control and survival.

Human epidermal growth factor receptor-2 is a proto-oncogene which is over-expressed in both breast ductal carcinoma and salivary duct carcinoma. Clinical studies of patients with metastatic breast cancer, using trastuzumab, a monoclonal antibody directed against human epidermal growth factor receptor-2, have shown significant efficacy in tumour response, resulting in improved survival. Such advances in immunohistochemistry, and in targeted immunotherapy for breast ductal carcinoma, should be applied to the treatment of salivary duct carcinoma.
Vowel reduction in Russian: No phonetics in phonology
Authors: IOSAD PAVEL
Published: April 2012

Much recent work in phonology concentrates on the role of sonority in the phenomenon of vowel reduction, capitalizing on two facts: that reduction involves raising and/or shortening and that higher vowels and schwa are normally interpreted as having low sonority. This paper presents a different approach to vowel reduction in Standard Russian. It is proposed that the apparent sonority-driven effects in Russian are epiphenomenal. In particular, reduction to schwa is outside the domain of phonological computation in Russian, being an artifact of reduced duration. Other types of neutralization arising in vowel reduction are potentially amenable to a sonority-based analysis, but I argue that current approaches to sonority-driven reduction suffer from representational shortcomings. When these shortcomings are rectified, however, sonority is unnecessary as an explicit factor in vowel reduction: standard markedness mechanisms suffice to explain the data.
La Economía de Santafé de Bogotá En 1810
Authors: Kalmanovitz Salomón , Rivera Edwin López
Published: April 2012

This essay shows that the growth of the economy of New Granada during the Eighteenth Century made an important impact on its political center, Santafé de Bogota, at least until 1808. Such prosperity was the result of a process of specialization and division of labor between different regions of the new kingdom, derived from the dynamics of gold mining that gave a strong impulse to Santafé's economy as a trade center for the handicraft production of Eastern Colombia and the fertile savanna surrounding it, which was a net food exporter. The Mint established in Santafé, which was a de facto monopoly, attracted merchants and miners who established there a center for the exchange of gold dust for coin.
Communication-oriented language teaching: Where are we now? Where do we go from here?
Authors: Littlewood William
Published: April 2012

In its early days, CLT was widely promoted as suitable for all contexts, but many questions have since been raised about what it really means and what versions of it (if any) are suited to specific learning situations. Experiences in Asia, where educational traditions and current realities often contrast strongly with those where CLT originated, have provided a major impetus for this questioning and the process has been reinforced by developments in the wider context, such as the postmethod perspective in language teaching and the decline of centre-to-periphery conceptions of modernization. CLT now serves not so much as a label for a specific approach as an umbrella term to describe all approaches that aim to develop communicative competence in personally meaningful ways. It also provides a framework for defining issues that research and exploratory practice need to address in the years ahead.
Survival of Dipteryx oleifera (Fabaceae) trees after Hurricane Ida in Nicaragua
Authors: Sarikas Christine , Urquhart Gerald R.
Published: April 2012

The impact of hurricanes on tropical forests has been well documented in recent decades, with hurricane disturbance hypothesized to be a leading contributor to maintenance of the high diversity of trees in lowland tropical rain forests (Frangi & Lugo 1991, Vandermeer et al. 2000). Hurricanes have a heterogeneous impact both on landscapes and tree species (Liu & Fearn 2000, Walker et al. 1996). Damage to trees can take many forms, from leaf loss to stem snapping to uprooting, and is variable across the landscape due to topography, wind speed, direction and tree density (Walker 1995).
Demography ofCycas micronesicaon Guam following introduction of the armoured scaleAulacaspis yasumatsui
Authors: Marler Thomas E. , Lawrence John H.
Published: April 2012

Following the 2003 invasion of the armoured scaleAulacaspis yasumatsuito Guam, changes to population traits of the dominantCycas micronesicawere determined. Belt transects with a width of 4 m and an average length of 120 m were established in October 2004 to document plant mortality until January 2011. Stem height, basal diameter and leaf number were also measured for each plant and used to determine density, demography and allometric relationships. Allometric traits and a left-skewed demographic structure of the pre-invasionC. micronesicahabitat documented a thriving population with high recruitment potential.Aulacaspis yasumatsuidispersed into the study site 4 mo after the initial census. All seedlings were killed within 9 mo and all juvenile plants were killed within 40 ± 10 mo. Mortality reached 92% by 6 y after chronic scale infestations. Allometry and demography of the 2011 survivors described a collapsingC. micronesicapopulation of stressed and reproductively challenged trees with no recruitment. This classic example of the enemy release hypothesis has resulted in a homogeneous decline in plant density from 2007–2011. The trend predicts extirpation ofC. micronesicafrom west Guam habitats by 2019.
Heavy impact on seedlings by the impala suggests a central role in woodland dynamics
Authors: O'Kane Christopher A. J. , Duffy Kevin J. , Page Bruce R. , Macdonald David W.
Published: April 2012

Research has increasingly established that mesoherbivores influence the regeneration of woody plants. However the relationship between mesoherbivore density and degree of impact, and the spatial component of this impact, has not been well established. Using a novel sampling design, we assessed in iMfolozi Park, South Africa, the impact of impala (Aepyceros melampus) across the full complement of woody species within the home range, evaluating its spatial component and relationship to impala density. We used four GPS collars, in separate breeding herds, and a GIS to detect zones of different density of impala in the landscape, thus defining a fine-grain browsing gradient. We assessed impact on woody recruits (≤ 0.5 m height) across this gradient by means of 1600 random 1 × 1-m quadrats. Densities of woody seedlings, and mean percentage of remaining canopy, were significantly less in areas of high impala density versus low-density areas. There was a significant correlation between increasing impala density and decreasing density of favoured woody recruits. We propose a hypothesis of impala-induced patch dynamics. It seems likely that the ubiquitous impala may create and sustain a shifting mosaic of patches, and thus function as a key determinant of landscape heterogeneity.