bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of collaborative interactivity in the observational practice of clinical skills
Authors: Grierson Lawrence E M , Barry Maureen , Kapralos Bill , Carnahan Heather , Dubrowski Adam 
Published: March 2012

Medical Education 2012: 46: 409–416Context  Video‐based observational practice can extend simulation‐based learning outside the training space. This study explores the value of collaborative feedback provided during observational practice to the acquisition of clinical skills.Methods  Nursing students viewed a video demonstrating the proper ventrogluteal injection technique before performing a videotaped pre‐test trial on a simulator. They were then assigned randomly to one of three observational practice groups: a group that observed the expert demonstration (EO group); a group that viewed the expert demonstration, self‐assessed their individual pre‐test and contrasted their self‐assessments with expert feedback (ESO group), and a group that observed the expert demonstration, self‐assessed and contrasted their assessments with those of an expert, and formed a community that engaged in peer‐to‐peer feedback (ESPO group). The observation of all videos, the provision of assessments and all networking occurred via an Internet‐mediated network. After 2 weeks, participants returned for post‐tests and transfer tests.Results  The pre‐test–post‐test analyses revealed significant interactions (global rating scale: F(2,22) = 4.00 [p = 0.033]; checklist: F(2,22) = 4.31 [p = 0.026]), which indicated that post‐test performance in the ESPO group was significantly better than pre‐test performance. The transfer analyses revealed main effects for both the global rating scale (F(2,23) = 6.73; p = 0.005) and validated checklist (F(2,23) = 7.04; p = 0.004) measures. Participants in the ESPO group performed better on the transfer test than those in the EO group.Conclusions  The results suggest that video‐based observational practice can be effective in extending simulation‐based learning, but its effectiveness is mediated by the amount of time the learner spends engaged in the practice and the type of learning activities the learner performs in the observational practice environment. We speculate that increasing collaborative interactivity supports observational learning by increasing the extent to which the educational environment can accommodate learners’ specific needs.
Opsin gene sequence variation across phylogenetic and population histories in Mysis (Crustacea: Mysida) does not match current light environments or visual‐pigment absorbance spectra
Authors: AUDZIJONYTE ASTA , PAHLBERG JOHAN , VILJANEN MARTTA , DONNER KRISTIAN , VÄINÖLÄ RISTO 
Published: March 2012

AbstractThe hypothesis that selection on the opsin gene is efficient in tuning vision to the ambient light environment of an organism was assessed in 49 populations of 12 Mysis crustacean species, inhabiting arctic marine waters, coastal littoral habitats, freshwater lakes (‘glacial relicts’) and the deep Caspian Sea. Extensive sequence variation was found within and among taxa, but its patterns did not match expectations based on light environments, spectral sensitivity of the visual pigment measured by microspectrophotometry or the history of species and populations. The main split in the opsin gene tree was between lineages I and II, differing in six amino acids. Lineage I was present in marine and Caspian Sea species and in the North American freshwater Mysis diluviana, whereas lineage II was found in the European and circumarctic fresh‐ and brackish‐water Mysis relicta, Mysis salemaai and Mysis segerstralei. Both lineages were present in some populations of M. salemaai and M. segerstralei. Absorbance spectra of the visual pigment in nine populations of the latter three species showed a dichotomy between lake (λmax = 554–562 nm) and brackish‐water (Baltic Sea) populations (λmax = 521–535 nm). Judged by the shape of spectra, this difference was not because of different chromophores (A2 vs. A1), but neither did it coincide with the split in the opsin tree (lineages I/II), species identity or current light environments. In all, adaptive evolution of the opsin gene in Mysis could not be demonstrated, but its sequence variation did not conform to a neutral expectation either, suggesting evolutionary constraints and/or unidentified mechanisms of spectral tuning.
nMAT1, a nuclear‐encoded maturase involved in the trans‐splicing of nad1 intron 1, is essential for mitochondrial complex I assembly and function
Authors: Keren Ido , Tal Liat , des Francs‐Small Catherine C. , Araújo Wagner L. , Shevtsov Sofia , Shaya Felix , Fernie Alisdair R. , Small Ian , Ostersetzer‐Biran Oren 
Published: March 2012

SummaryMitochondrial genomes (mtDNAs) in angiosperms contain numerous group II‐type introns that reside mainly within protein‐coding genes that are required for organellar genome expression and respiration. While splicing of group II introns in non‐plant systems is facilitated by proteins encoded within the introns themselves (maturases), the mitochondrial introns in plants have diverged and have lost the vast majority of their intron‐encoded ORFs. Only a single maturase gene (matR) is retained in plant mtDNAs, but its role(s) in the splicing of mitochondrial introns is currently unknown. In addition to matR, plants also harbor four nuclear maturase genes (nMat 1 to 4) encoding mitochondrial proteins that are expected to act in the splicing of group II introns. Recently, we established the role of one of these proteins, nMAT2, in the splicing of several mitochondrial introns in Arabidopsis. Here, we show that nMAT1 is required for trans‐splicing of nad1 intron 1 and also functions in cis‐splicing of nad2 intron 1 and nad4 intron 2. Homozygous nMat1 plants show retarded growth and developmental phenotypes, modified respiration activities and altered stress responses that are tightly correlated with mitochondrial complex I defects.
Molecular background of D‐negative phenotype in the Tunisian population
Authors: Moussa H. , Tsochandaridis M. , Chakroun T. , Jridi S. , Abdelneji B. , Hmida S. , Silvy M. , Bailly P. , Gabert J. , Levy‐Mozziconacci A. , Jemni‐Yacoub Saloua 
Published: March 2012

Background: Most studies of the molecular basis of Rhesus D‐negative phenotype have been conducted in Caucasian and African populations. A comprehensive survey of RHD alleles was lacking in people from North Africa (Tunisians, Moroccans and Algerians) which could be very efficient for managing donors and patients carrying an RHD molecular variant. We analyse the molecular background of D‐negative population in Tunisia in the present study.Materials and methods: Blood samples were collected from native Tunisians. A total of 448 D‐negative donors from different regions of Tunisia were analysed by RHD genotyping according to an adopted strategy using real‐time PCR, ASP‐PCR and sequencing.Results: Among the 448 D‐negative samples, 443 were phenotyped unequivocally as true D‐negative including three molecular backgrounds which were RHD gene deletion (n = 437), RHDψ pseudogene (n = 2) and RHD‐CE‐D hybrid gene (n = 4) with the respective frequencies of 0·9900, 0·0023 and 0·0046. The remaining five samples, in discordance with the serological results, were identified as two weak D type 11, one weak D type 29, one weak D type 4·0 and one DBT‐1 partial D.Conclusion: This study showed that the Tunisian population gets closer to Caucasians, given that the RHD gene deletion is the most prevalent cause of D‐negative phenotype, but it is slightly different by the presence of the RHDψ pseudogene which was found with a very low frequency compared with that described in the African population. Nevertheless, the relative occurrence of weak D variants among studied serologically D‐negative samples make necessary the adaptation of RHD genotyping strategy to the spectrum of prevalent alleles.
An Improved Growth Medium to Assess Mycelial Compatibility Groups in Sclerotium rolfsii
Authors: Remesal Efrén , Navas‐Cortés Juan A. 
Published: March 2012

AbstractMycelial compatibility is assayed mainly by pairing mycelial plugs of field isolates on Petri dishes with agar media. Although methodologically simple, mycelial compatibility testing requires an artificial growth medium that permits the identification of compatible and incompatible interactions. In this work, several growth media were studied to assess consistently mycelial interactions between Sclerotium rolfsii isolates. A modification of Patterson’s medium with an increment of 25% glucose from the original concentration at a rate of 23.4 g/l and amended with 180 μl/l of red food colouring was the most effective combination for enhancing the size, density and distinctiveness of the aversion zone between incompatible isolates. This medium allowed the unequivocal identification of compatible and incompatible reactions of a set of five S. rolfsii isolates, which could be determined quickly after 5 days of incubation in the dark at 25°C. This new formulation improved significantly and consistently the assessment of the aversion zone reaction that was visible as a red line on the colony reverse as compared to that assessed using previous media formulations, for which the visualization of aversion zones was scarcely discernible. The utility of the improved growth medium was validated by microscopic observations of the contact area of hyphal pairings between isolates of S. rolfsii in microscope slide cultures.
Diagnosis of invasive fungal infections using real‐time PCR assay in paediatric acute leukaemia induction
Authors: Mandhaniya Sushil , Iqbal Sobuhi , Sharawat Surender Kumar , Xess Immaculata , Bakhshi Sameer 
Published: March 2012

SummaryInvasive fungal infections (IFI) lead to morbidity and mortality in neutropenic patients and in allogenic stem cell transplantation. Serum‐based fungal detection assays have limitation of specificity or sensitivity. Studies on fungal DNA detection using real‐time PCR in childhood leukaemia are lacking. The aim of this study was to develop sensitive and specific diagnostic tools for IFI in paediatric acute leukaemia patients using real‐time PCR. Of 100 randomised paediatric acute leukaemia patients receiving antifungal prophylaxis with voriconazole/amphotericin B, single peripheral whole blood sample in EDTA was used for Pan‐AC real‐time PCR assay (detects nine Candida and six Aspergillus species) in patients who failed prophylaxis due to proven, probable, possible or suspected fungal infections. PCR results were retrospectively correlated with clinical profile. Real‐time PCR test was positive in 18/29 (62%) patients who failed prophylaxis. The only patient with proven IFI (mucormycosis), real‐time PCR assay was negative. Real‐time PCR was positive in 2/4 (50%) patients with possible and 16/24 (66.6%) suspected IFI and 5/10 (50%) patients with pneumonia. By applying method A/B, sensitivity and positive predictive value could not be commented due to unproven Aspergillus or Candida infections; specificity and negative predictive values (NPV) were 41% and 100% respectively; by method C (included episodes of possible IFI as true positive), sensitivity, specificity, PPV and NPV were 50%, 36%, 11% and 81% respectively. In those with suspected IFI, 8/24 (33.3%) were PCR negative and unnecessarily received empirical antifungal therapy (EAFT). Real‐time PCR is a practical, rapid, non‐invasive screening test for excluding IFI in paediatric leukaemia. The high NPV makes real‐time PCR a promising tool to use this prior to initiating EAFT in antibiotic‐resistant febrile neutropenic patients; this would avoid toxicity, cost and hospitalisation for EAFT (ClinicalTrials.gov identifier:NCT00624143).
Clinical characterization of gastric lesions initially diagnosed as low‐grade adenomas on forceps biopsy
Authors: Kasuga Akiyoshi , Yamamoto Yorimasa , Fujisaki Junko , Okada Kazuhisa , Omae Masami , Ishiyama Akiyoshi , Hirasawa Toshiaki , Chino Akiko , Tsuchida Tomohiro , Igarashi Masahiro , Hoshino Etsuo , Yamamoto Noriko , Kawaguchi Minoru , Fujita Rikiya 
Published: March 2012

Aim:  The aim of this study was to elucidate characteristics of gastric lesions that are initially diagnosed as low‐grade adenomas and to establish appropriate treatment.Methods:  We retrospectively reviewed 231 lesions initially diagnosed as gastric adenomas. All forceps biopsy samples were histologically diagnosed as category 3 low‐grade adenomas according to the revised Vienna Classification. All patients underwent endoscopic resection with endoscopic findings and post‐resection diagnoses evaluated subsequently.Results:  Sixty‐three lesions were initially diagnosed as depressed adenomas, and 168 lesions were diagnosed as protruding adenomas. The depressed lesions were significantly smaller (11.6 ± 5.0 mm) than the protruding lesions (17.0 ± 10.8 mm) (P < 0.001). Diagnoses reclassified to category 4 mucosal high‐grade neoplasia (i.e. high‐grade adenoma, adenocarcinoma in adenoma and adenocarcinoma) were more frequent among depressed lesions (52.4%) than among protruding lesions (31.0%) (P = 0.004). Multivariate analysis of all 231 lesions showed that lesion size larger than 20 mm (P < 0.001) and depressed appearance (including central depression) (P < 0.001) were significant independent factors suggesting cancer. For the 168 protruding lesions, lesion size larger than 20 mm (P < 0.001) and central depression (P < 0.001) were significant independent factors suggesting cancer. For the 63 depressed lesions, lesion size larger than 15 mm (P = 0.016) and a moth‐eaten appearance (P = 0.017) were significant independent factors in the pre‐treatment diagnosis of cancer.Conclusions:  Adenocarcinoma lesions were often found in depressed lesions and protruding lesions with central depression. Endoscopic resection for total biopsy is recommended, even if forceps biopsy indicates low‐grade adenoma, as pre‐treatment biopsy may be inadequate for an accurate histological diagnosis.
Efficacy of acetic acid‐spraying method in diagnosing extension of barrett's cancer under the squamous epithelium
Authors: Yamagata Taku , Hirasawa Dai , Fujita Naotaka , Obana Takashi , Sugawara Toshiki , Ohira Tetsuya , Harada Yoshihiro , Maeda Yuki , Koike Yoshiki , Suzuki Kenjiro , Yamamoto Yasuchika , Kusaka Jun , Tanaka Megumi , Noda Yutaka 
Published: March 2012

Aim:  Endoscopic diagnosis of the lateral extension of Barrett's cancer under the squamous epithelium (BCUS) is sometimes difficult because the cancer is unobservable in the esophageal lumen. The aim of the present study was to clarify the endoscopic features of the extension of BCUS and verify the usefulness of the acetic acid‐spraying method (AAS) for diagnosis.Methods:  A total of 25 patients with Barrett's cancer who had undergone endoscopic resection were included in this study. Histological examination of patients' resected specimens was performed to identify the presence of BCUS. Then, the endoscopic images of the BCUS cases were reviewed to summarize the findings and to evaluate the feasibility of diagnosing the extent of BCUS with each imaging technique.Results:  Of the 25 patients, 10 (40%) had BCUS. With white‐light imaging, subtle reddish change was observed in the area of BCUS in 80% of the patients, and a flat elevated lesion was recognized in 30%. With narrow band imaging, slight brownish change was observed in the area of BCUS in 86% of the patients. Slight white changes were visualized in all cases with AAS. The extension of BCUS was correctly diagnosed by white‐light imaging, narrow band imaging and AAS in 50%, 43% and 100% of the cases, respectively. Histology verified the opening of cancerous glands, which extended under the squamous epithelium, into the esophagus in the area showing slight white changes by AAS.Conclusion:  AAS can be useful for diagnosing the extension of BCUS.
Relationship between vomiting reflex during esophagogastroduodenoscopy and dyspepsia symptoms
Authors: Enomoto Shotaro , Watanabe Mika , Yoshida Takeichi , Mukoubayashi Chizu , Moribata Kosaku , Muraki Yosuke , Shingaki Naoki , Deguchi Hisanobu , Ueda Kazuki , Inoue Izumi , Maekita Takao , Iguchi Mikitaka , Tamai Hideyuki , Kato Jun , Fujishiro Mitsuhiro , Oka Masashi , Mohara Osamu , Ichinose Masao 
Published: March 2012

Aim:  Although frequent vomiting reflexes during esophagogastroduodenoscopy (EGD) causes suffering in patients, very few studies have investigated the characteristics of subjects who frequently develop vomiting reflexes. This study examined the incidence of the vomiting reflex and related factors, especially upper gastrointestinal symptoms, among individuals undergoing transoral EGD.Methods:  Subjects included 488 consecutive adults (mean age, 56.1 ± 8.9 years) who underwent transoral EGD for gastric cancer screening between February 2010 and March 2011. All procedures were performed by an endoscopist with 15 years of experience. Based on a questionnaire survey using the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG), symptoms (dyspepsia and acid reflux symptoms) and the number of vomiting reflexes during EGD were recorded.Results:  Of the 488 subjects, 271 (56%) developed vomiting reflexes (mean, 4.2 times). This reflex‐positive group was younger (54.3 ± 9.5 years) than the reflex‐negative group (58.3 ± 7.7 years, P < 0.001). The number of subjects in the reflex‐positive group with a high FSSG dyspepsia score (2.27 ± 2.57 vs 1.23 ± 1.84; P < 0.001), acid reflux symptom score (1.96 ± 2.22 vs 1.34 ± 2.14; P < 0.01) or an esophageal hiatal hernia (14.8% vs 4.6%; P < 0.001) was significantly higher than in the reflex‐negative group. Multivariate analysis also showed a significant correlation between these four factors and the occurrence of vomiting reflexes. Using an FSSG dyspepsia score of 1 as the cut‐off offered 68% sensitivity and 57% specificity for predicting the occurrence of vomiting reflexes.Conclusion:  Based on FSSG questionnaire responses on upper gastrointestinal symptoms, dyspepsia symptoms, in particular, are related to presence of vomiting reflexes during EGD.
Flicking method: A novel colonoscope insertion method for surveillance colonoscopy in ulcerative colitis patients
Authors: Sato Toru , Miyawaki Tetsumaru , Katsuno Tatsuro , Nakagawa Tomoo , Inoue Masahito , Watanabe Yoshiyuki , Hishikawa Etsuo , Arai Makoto , Yokosuka Osamu 
Published: March 2012

Aim:  Periodic surveillance colonoscopy is required for patients with ulcerative colitis to detect colitis‐associated dysplasia at an early stage. However, sometimes colonoscopy may damage the fragile mucosa of patients with ulcerative colitis. The aim of this study was to devise a new method of surveillance colonoscopy for patients with mild to moderate ulcerative colitis.Methods:  The ‘flicking method’ of colonoscope insertion was recently developed by our team. It is a completely novel method that involves using the elastic force of the colonoscope to introduce it into the deeper regions while using colon mucosa patterns as a guide. The subjects were 66 hospital outpatients with ulcerative colitis who underwent colonoscopies during a 2‐year period, from April 2006 to March 2008, with both the conventional insertion method and the flicking method.Results:  Cecal intubation rate, insertion time, patient pain level, change in number of defecations pre‐ and post‐colonoscopy, and change in severity pre‐ and post‐colonoscopy were compared between the conventional and flicking methods. The flicking method was superior in all respects.Conclusions:  The flicking method is a novel colonoscope insertion method that is regarded as particularly useful in cases when the intestinal mucosa is fragile, as is the case with ulcerative colitis patients.
Robust Detection and Identification of Sparse Segments in Ultrahigh Dimensional Data Analysis
Authors: Tony Cai T. , Jessie Jeng X. , Li Hongzhe 
Published: March 2012

SummaryCopy number variants (CNVs) are alternations of DNA of a genome that result in the cell having less or more than two copies of segments of the DNA. CNVs correspond to relatively large regions of the genome, ranging from about one kilobase to several megabases, that are deleted or duplicated. Motivated by CNV analysis based on next generation sequencing data, we consider the problem of detecting and identifying sparse short segments hidden in a long linear sequence of data with an unspecified noise distribution. We propose a computationally efficient method that provides a robust and near optimal solution for segment identification over a wide range of noise distributions. We theoretically quantify the conditions for detecting the segment signals and show that the method near optimally estimates the signal segments whenever it is possible to detect their existence. Simulation studies are carried out to demonstrate the efficiency of the method under various noise distributions. We present results from a CNV analysis of a HapMap Yoruban sample to illustrate the theory and the methods further.
Sexual behaviours, knowledge and attitudes regarding safe sex, and prevalence of non‐viral sexually transmitted infections among attendees of youth clinics in St. Petersburg, Russia
Authors: Shipitsyna E. , Krasnoselskikh T. , Zolotoverkhaya E. , Savicheva A. , Krotin P. , Domeika M. , Unemo M. 
Published: March 2012

AbstractBackground  Adolescents and young adults are at increased risk of sexually transmitted infections (STIs). Knowledge of STI prevalence and risk factors are essential tools to elaborate preventive strategies. However, internationally reported studies on epidemiology of STIs among the youth in Russia are mainly lacking.Objectives  To ascertain sexual behaviours, knowledge and attitudes about safe sex and prevalence and correlates with STIs in attendees of youth clinics in St. Petersburg, Russia.Methods  A total of 301 women and 131 men, who self‐referred for STI testing, completed a questionnaire and were screened for Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis using nucleic acid amplification tests.Results  The overall STI prevalence was 16.9%, and similar in the female patients and male patients (15.6% and 19.8% respectively). C. trachomatis, N. gonorrhoeae, M. genitalium and T. vaginalis were detected in 13%, 2.5%, 4.6% and 1.2% of the attendees respectively. The men displayed riskier sexual behaviours and worse knowledge and attitudes regarding safe sex compared to the women, with the most distinguishing features being younger age at first intercourse (P < 0.0005), higher numbers of sex partners during lifetime (P = 0.001) and latest 6 months (P < 0.0005), more frequently consuming alcohol (P < 0.0005), poorer knowledge of STI/HIV prevention measures (P < 0.0005), and less positive attitudes towards safe sex (P = 0.001). However, no significant predictors of STI positivity were found in the men. In the women, the strongest predictors of STI positivity were young age (15–19 years) and multiple sex partners (≥2) during latest 6 months.Conclusions  The overall prevalence of STIs among users of STI services at youth clinics in St. Petersburg was high. Comprehensive epidemiological data on STI prevalence and sexual behaviour correlates are necessary to initiate new and strengthen existing STI prevention programmes for the youth, in Russia as well as in many other settings.