Miracle-dz/UniFAR-FTUs huggingface dataset:
Comparison of Protein A Gene Sequencing with Pulsed-Field Gel Electrophoresis and Epidemiologic Data for Molecular Typing of Methicillin-Resistant Staphylococcus aureus

ABSTRACT The epidemiologic relatedness of methicillin-resistantStaphylococcus aureus (MRSA) isolates is currently determined by analysis of chromosomal DNA restriction patterns by pulsed-field gel electrophoresis (PFGE). We have evaluated an alternative typing system (MicroSeq StaphTrack Kit; Perkin-Elmer Biosystems) based on the sequence analysis of the chromosomally encoded polymorphic repeat X region of the S. aureus protein A (spa) gene. A total of 69 clinical MRSA isolates were divided into 18 groups according to the number and nucleotide sequences of the spa repeats. Molecular typing results obtained both by spa sequencing and from the PFGE patterns were concordant except for one group, which contained 20 isolates recovered over a 2-year period from hospitalized patients at the Mayo Clinic. Although the spa typing patterns were indistinguishable for those isolates, PFGE analysis yielded seven related but distinguishable patterns. Further coagulase gene sequence analysis subtyped those 20 strains into four groups which followed distinct temporal and geographic distributions. During a 2-year epidemic period there were up to 7 fragment changes in PFGE patterns among epidemiologically related isolates, suggesting that PFGE may be unsuitable for long-term typing of strains involved in epidemics. Although more limited than PFGE in discriminatory power, spa sequencing analysis could be used as a screening method for typing of MRSA strains because of the shorter turnaround time, ease of use, and the inherent advantages of sequence analysis, storage, and sharing of information.
Burnout Syndrome Among Health Care Students

The aim of this study was to examine the effect of Type D personality, along with other personality traits (resilience and sense of coherence), on burnout syndrome and its counterpart, engagement, among students of nursing, midwifery, and psychology. A cross-sectional study was conducted on 97 university students (91.9% females; M age = 20.2 ± 1.49 years). A Type D personality subscale, School Burnout Inventory, Utrecht Work Engagement Scale, Sense of Coherence Questionnaire, and Baruth Protective Factor Inventory were used. Linear regression models, Student’s t test, and Pearson’s correlation analysis were employed. Negative affectivity, a dimension of Type D personality, was a significant personality predictor for burnout syndrome (β = .54; 95% CI = [0.33, 1.01]). The only significant personality predictor of engagement was a sense of coherence. Students who were identified as having Type D personality characteristics scored significantly higher on the burnout syndrome questionnaire (t = −2.58, p < .01). In health care professions, personality predictors should be addressed to prevent burnout.
Miniprobe confocal laser microscopy for the detection of invisible neoplasia in patients with Barrett’s oesophagus

Objective: The biggest challenge in endoscopic surveillance of Barrett’s oesophagus is better detection of neoplasia in mucosa of normal macroscopic appearance. We evaluated in vivo miniprobe confocal laser microscopy (CLM) for the detection of invisible Barrett’s neoplasia. Design: Prospective two-centre trial in two phases: phase I to establish criteria of Barrett’s neoplasia and phase II to test these criteria. Patients and intervention: 296 biopsy sites in 38 consecutive patients with Barrett’s oesophagus (mean age 62.1 years, 89.5% men, median length of the Barrett’s oesophagus, 3 cm) were examined with standard high-resolution endoscopy and by miniprobe CLM, with precise matching of CLM recordings to biopsy sites. CLM image criteria for normal versus neoplastic Barrett’s oesophagus were established from 95 biopsies of 15 patients (phase I); these criteria were then prospectively tested on 201 biopsies from the remaining patients without visible focal changes (phase II). All 201 CLM video recordings from phase II cases were randomised and blindly evaluated by two gastroenterologists. Main outcome measure: The primary endpoints were accuracy values in diagnosing HGIN or early carcinoma (EC) on a per-biopsy basis. Secondary endpoints included inter-observer agreement. Results: All initially defined miniprobe CLM criteria (phase I) were significantly more frequently detected in HGIN/EC sites compared with sites with no or low grade neoplasia (phase II). In a per-biopsy analysis, sensitivity and specificity for two independent investigators were 75.0% and 88.8%, and 75.0% and 91.0%, respectively, translating at best into a positive predictive value of 44.4% and a negative predictive value of 98.8%. Inter-observer agreement was good (kappa 0.6). Conclusion: Miniprobe CLM showed a high negative predictive value for the diagnosis of endoscopically invisible neoplasia in Barrett’s oesophagus; sensitivity, however, has still to be improved.
A Blended Learning Approach to Course Design and Implementation

Blended learning has become an increasingly popular form of e-learning, and is particularly suitable to the process of transitioning towards e-learning from traditional forms of learning and teaching. This paper describes the use of the blended e-learning model, which is based on a mixture of collaborative learning, problem-based learning (PBL) and independent learning, in a course ldquoTeaching Methods in Information Science,rdquo given at the University of Rijeka, Rijeka, Croatia. This model is realized as a combination of a face-to-face environment and online learning, using a proprietary learning management system (LMS) named adaptive hypermedia courseware (AHyCo). AHyCo is based on adaptive hypermedia and in addition to supporting learning and testing, introduces completely new constructivist and cognitivist elements to education. By supporting collaborative and project-oriented activities AHyCo promotes students' motivation for learning and establishes learning as an active and interactive process. This paper describes both the technology for, and the methodological approach to, course design and development which is aimed at supporting the evolution from traditional teaching to active learning, and raising interest in the topics of e-learning and Web courseware development among IT students. A survey conducted in the end of the course showed that students were satisfied with the pedagogical approach, and their academic achievements were also better than expected. Particularly important is that the dropout rate was greatly diminished, which could be related to students' satisfaction with the support they received from the instructor and the system.
Steep, coincident, and concordant clines in mitochondrial and nuclear‐encoded genes in a hybrid zone between subspecies of Atlantic killifish, Fundulus heteroclitus

Abstract Steep genetic clines resulting from recent secondary contact between previously isolated taxa can either gradually erode over time or be stabilized by factors such as ecological selection or selection against hybrids. We used patterns of variation in 30 nuclear and two mitochondrial SNPs to examine the factors that could be involved in stabilizing clines across a hybrid zone between two subspecies of the Atlantic killifish, Fundulus heteroclitus. Increased heterozygote deficit and cytonuclear disequilibrium in populations near the center of the mtDNA cline suggest that some form of reproductive isolation such as assortative mating or selection against hybrids may be acting in this hybrid zone. However, only a small number of loci exhibited these signatures, suggesting locus‐specific, rather than genomewide, factors. Fourteen of the 32 loci surveyed had cline widths inconsistent with neutral expectations, with two SNPs in the mitochondrial genome exhibiting the steepest clines. Seven of the 12 putatively non‐neutral nuclear clines were for SNPs in genes related to oxidative metabolism. Among these putatively non‐neutral nuclear clines, SNPs in two nuclear‐encoded mitochondrial genes (SLC25A3 and HDDC2), as well as SNPs in the myoglobin, 40S ribosomal protein S17, and actin‐binding LIM protein genes, had clines that were coincident and concordant with the mitochondrial clines. When hybrid index was calculated using this subset of loci, the frequency distribution of hybrid indices for a population located at the mtDNA cline center was non‐unimodal, suggesting selection against advanced‐generation hybrids, possibly due to effects on processes involved in oxidative metabolism.
Mediastinal Lymph Nodes in Patients With Non-small Cell Lung Cancer: Preliminary Experience With Diffusion-weighted MR Imaging

Objectives The purpose of our study was to describe our preliminary experience of evaluating mediastinal lymph node metastases with diffusion-weighted magnetic resonance (MR) imaging in patients with non-small cell lung cancer. Materials and Methods Forty-two consecutive patients with non-small cell lung cancer underwent preoperative diffusion-weighted MR imaging using a non-breath-hold short inversion time inversion recovery-echo planar imaging sequence with a high b value of 1000 s/mm2. An experienced thoracic radiologist prospectively evaluated each study for mediastinal lymph node metastases on a per-patient basis. On diffusion-weighted MR imaging, mediastinal lymph node metastasis was defined as a focus of low signal intensity at the site of a visible lymph node on corresponding T2-weighted image. The MR results were correlated with histopathologic findings. Results Diffusion-weighted MR imaging demonstrated mediastinal lymph node metastasis in 4 (80%) of 5 patients with pathologically proven metastasis and accurately identified 36 (97%) of 37 patients without mediastinal lymph node metastasis. Thus, 40 (95%) of 42 patients were accurately diagnosed. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of diffusion-weighted MR imaging for mediastinal lymph node metastasis were 80%, 97%, 80%, 97%, and 95%, respectively. Conclusions Our preliminary results show that diffusion-weighted MR imaging has a high negative predictive value for excluding mediastinal lymph node metastases from non-small cell lung cancer and has the potential to be a reliable alternative non-invasive imaging method for the preoperative staging of mediastinal lymph node in patients with non-small cell lung cancer.
Human immunodeficiency virus infection and syncytium formation in HeLa cells expressing glycophospholipid-anchored CD4

The CD4 molecule, a glycoprotein expressed primarily on the cell surface of specific T lymphocytes, is thought to function in T-cell antigen recognition and activation. In addition, CD4 serves as a receptor for human immunodeficiency virus type 1 (HIV-1) by a direct interaction with the HIV-1 surface glycoprotein (gp120). To further characterize the HIV-1-cell interaction, a HeLa cell line was established that expressed a chimeric molecule of CD4 and decay-accelerating factor (DAF). In the chimeric CD4-DAF molecule the transmembrane and cytoplasmic domains of CD4 were deleted and replaced with the carboxy-terminal 37 amino acids of DAF. This resulted in the anchoring of the extracellular domain of CD4 to the cell membrane via a glycophospholipid linkage. The glycophospholipid-anchored CD4 had a molecular size of approximately 56 to 62 kDa and was released following treatment of the cells with phosphatidylinositol-specific phospholipase C. HeLa cells expressing the CD4-DAF hybrid could be infected with HIV-1, as evidenced by reverse transcriptase activity, p24 core antigen content, and infectious virus production. In addition, transfection of the HeLa CD4-DAF cells with a plasmid that directs the synthesis of HIV-1 envelope glycoproteins or cocultivation with HeLa cells expressing the virus glycoproteins resulted in syncytium formation. These results indicate that the transmembrane and cytoplasmic domains of the CD4 molecule are dispensable for both HIV infection and syncytium formation.
The challenge of teaching large classes in higher education in South Africa : a battle to be waged outside the classroom

INTRODUCTION The main focus of my work as an educational development practitioner is to help strengthen the quality of teaching in higher education. My aim is to work with colleagues to ‘get it right’ and by that I mean getting it right for all role players, namely students, lecturers and institutions. For students, this means supporting them in their learning and engagement with disciplines and professions; for lecturers, enhancing our sense of integrity and fulfilment as teachers and academics; and for institutions, developing systems and programmes for delivering quality educational experiences in South Africa at the start of the 21st century.
Catecholamines predict outcome in traumatic brain injury

Activation of the sympathetic nervous system attends traumatic brain injury, but the association of the severity of neurological impairment and recovery with the extent of sympathetic nervous system stimulation is poorly defined. In this study, plasma norepinephrine (NE), epinephrine (E), and dopamine (DA) levels were measured serially in 33 patients with traumatic brain injury and compared with the Glasgow Coma Score (GSC), which was obtained concurrently. A catecholamine gradient that reflected the extent of brain injury was demonstrated within 48 hours of the injury. In patients with a GCS of 3 to 4, NE and E levels increased four‐ to fivefold and the DA level increased threefold above normal (NE, 1686 ± 416 pg/ml; E, 430 ± 172 pg/ml; DA, 236 ± 110 pg/ml), while patients with mild brain injury (GCS, ≥ 11) had slightly elevated or normal levels. Patients with marked (GCS, 5 to 7) and moderate (GCS, 8 to 10) traumatic brain injuries had intermediate levels. The prognostic value of determining admission levels of NE was shown in patients with an admission GCS of 3 to 4 1 week after injury. Patients with severe and unchanging neurological impairment 1 week after injury had markedly elevated initial NE levels (2,176 ± 531 pg/ml), whereas initial NE levels (544 ± 89 pg/ml) were only mildly elevated in patients who improved to a GCS of greater than 11. These data indicate that markedly elevated NE levels predict outcome in patients with comparable neurological deficits. Thus levels of circulating catecholamines are excellent endogenous and readily quantifiable markers that appear to reflect the extent of brain injury and that may predict the likelihood of recovery.
Systematic Analysis of the Relation of Electron Transport and ATP Synthesis to the Photodamage and Repair of Photosystem II in Synechocystis1

The photosynthetic machinery and, in particular, the photosystem II (PSII) complex are susceptible to strong light, and the effects of strong light are referred to as photodamage or photoinhibition. In living organisms, photodamaged PSII is rapidly repaired and, as a result, the extent of photoinhibition represents a balance between rates of photodamage and the repair of PSII. In this study, we examined the roles of electron transport and ATP synthesis in these two processes by monitoring them separately and systematically in the cyanobacterium Synechocystis sp. PCC 6803. We found that the rate of photodamage, which was proportional to light intensity, was unaffected by inhibition of the electron transport in PSII, by acceleration of electron transport in PSI, and by inhibition of ATP synthesis. By contrast, the rate of repair was reduced upon inhibition of the synthesis of ATP either via PSI or PSII. Northern blotting and radiolabeling analysis with [35S]Met revealed that synthesis of the D1 protein was enhanced by the synthesis of ATP. Our observations suggest that ATP synthesis might regulate the repair of PSII, in particular, at the level of translation of the psbA genes for the precursor to the D1 protein, whereas neither electron transport nor the synthesis of ATP affects the extent of photodamage.
Asthma: The importance of dysregulated barrier immunity

Chronic asthma is an inflammatory disease of the airway wall that leads to bronchial smooth muscle hyperreactivity and airway obstruction, caused by inflammation, goblet cell metaplasia, and airway wall remodeling. In response to allergen presentation by airway DCs, T‐helper lymphocytes of the adaptive immune system control many aspects of the disease through secretion of IL‐4, IL‐5, IL‐13, IL‐17, and IL‐22, and these are counterbalanced by cytokines produced by Treg cells. Many cells of the innate immune system such as mast cells, basophils, neutrophils, eosinophils, and innate lymphoid cells also play an important role in disease pathogenesis. Barrier epithelial cells are being ever more implicated in disease pathogenesis than previously thought, as these cells have in recent years been shown to sense exposure to allergens via pattern recognition receptors and to activate conventional and inflammatory‐type DCs and other innate immune cells through the secretion of thymic stromal lymphopoietin, granulocyte‐macrophage colony stimulating factor, IL‐1, IL‐33, and IL‐25. Understanding this cytokine crosstalk between barrier epithelial cells, DCs, and immune cells provides important insights into the mechanisms of allergic sensitization and asthma progression as discussed in this review.
Strategies for the development of gadolinium‐based ‘q’‐activatable MRI contrast agents

The emergence and rapid development of activatable contrast agents (CAs), whose relaxivity changes in response to the variation of a specific marker in the surrounding physiological microenvironment, have expanded the scope of MRI beyond anatomical and functional imaging to also convey information at the cellular and molecular level. The essence of an activatable MRI CA is the difference in relaxivity before and after a change in a physiological variable: the larger the difference, the better the CA. In this review, strategies for the design of activatable gadolinium CAs, with a switching mechanism based on the modulation of hydration (q), sensitive to common variables in the physiological microenvironment, such as pH, light, redox and metal ions, are illustrated and discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Organized Crime as the Link between Inequality and Corruption

We study a model that establishes a novel theoretical rationale for the empirically well-documented relation between inequality and corruption. According to our model, inequality can nurture corruption by empowering organized crime because collusion between local police forces and criminal organizations is more likely in societies characterized by high inequality or weak security forces. Law enforcement and organized crime have a strong incentive to collude due to efficiency gains from specialization. However, their agreement breaks down when the mobsters can no longer credibly commit to joint rent maximization and thus start to compete with law enforcement for citizens’ wealth. The mobsters then non-violently monopolize the market for extortion by undercutting the police forces, similar to a strategy of predatory pricing. Criminal collusion is thus not very different from its corporate equivalent; hence, similar policy measures should be promising. In addition, our model also suggests that the criminal organization’s higher efficiency in extracting rents has a greater impact when the relative power between law enforcement and organized crime is rather balanced. Accordingly, when violent conflict becomes less predictable, non-violent elements of relative power become more relevant. Our model also allows for the interpretation that in the absence of strong social norms against corruption, organized crime is more difficult to challenge.
Leptin Signaling Promotes the Growth of Mammary Tumors and Increases the Expression of Vascular Endothelial Growth Factor (VEGF) and Its Receptor Type Two (VEGF-R2)*

To gain insight into the mechanism(s) by which leptin contributes to mammary tumor (MT) development we investigated the effects of leptin, kinase inhibitors, and/or leptin receptor antagonists (LPrA2) on 4T1 mouse mammary cancer cells in vitro and LPrA2 on 4T1-MT development in vivo. Leptin increases the expression of vascular endothelial growth factor (VEGF), its receptor (VEGF-R2), and cyclin D1 through phosphoinositide 3-kinase, Janus kinase 2/signal transducer and activator of transcription 3, and/or extracellular signal-activated kinase 1/2 signaling pathways. In contrast to leptin-induced levels of cyclin D1 the changes in VEGF or VEGF-R2 were more dependent on specific signaling pathways. Incubation of 4T1 cells with anti-VEGF-R2 antibody increased leptin-mediated VEGF expression suggesting an autocrine/paracrine loop. Pretreatment of syngeneic mice with LPrA2 prior to inoculation with 4T1 cells delayed the development and slowed the growth of MT (up to 90%) compared with controls. Serum VEGF levels and VEGF/VEGF-R2 expression in MT were significantly lower in mice treated with LPrA2. Interestingly, LPrA2-induced effects were more pronounced in vivo than in vitro suggesting paracrine actions in stromal, endothelial, and/or inflammatory cells that may impact the growth of MT. Although all the mechanism(s) by which leptin contributes to tumor development are unknown, it appears leptin stimulates an increase in cell numbers, and the expression of VEGF/VEGF-R2. Together, these results provide further evidence suggesting leptin is a MT growth-promoting factor. The inhibition of leptin signaling could serve as a potential adjuvant therapy for treatment of breast cancer and/or provide a new target for the designing strategies to prevent MT development.