68 research outputs found

    Pengembangan Lembar Kegiatan Siswa (Lks) Kimia Sma/ma Berbasis Learning Cycle 5e Pada Materi Laju Reaksi

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    Penelitian ini bertujuan untuk: (1) mengembangkan Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E, (2) mengetahui kualitas Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E, (3) mengetahui efektivitas Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E untuk meningkatkan prestasi belajar siswa. Penelitian dan pengembangan Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E menggunakan prosedur penelitian dan pengembangan dari Borg and Gall yang disederhanakan menjadi 9 tahapan yaitu: (1) penelitian pendahuluan dan pengumpulan data, (2) perencanaan, (3) pengembangan produk, (4) uji coba lapangan awal, (5) revisi produk awal, (6) uji coba pelaksanaan lapangan, (7) penyempurnaan produk hasil uji coba lapangan, (8) uji coba pelaksanaan lapangan, (9) penyempurnaan produk akhir. Analisis Data yang digunakan adalah analisis deskriptif kualitatif. Hasil Penelitian menunjukkan: (1) telah berhasil dikembangkan Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E pada materi Laju Reaksi yang dilakukan berdasarkan tahapan penelitian dan pengembangan R&D yang terdiri dari 9 tahapan, (2) kualitas Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E pada materi Laju Reaksi memiliki kualitas sangat baik pada aspek komponen kelayakan isi, bahasa, penyajian dan kegrafisan dengan persentase sebesar 84,06% berdasarkan penilaian siswa dan 90,88% berdasarkan penilaian guru, (hasil uji efektivitas pada aspek pengetahuan terdapat perbedaan antara kelas eksperimen (pembelajaran dengan menggunakan model Learning Cycle 5E disertai Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E ) dan kelas baseline (pembelajaran dengan menggunakan model pembelajaran Learning Cycle 5E tanpa disertai Lembar Kegiatan Siswa (LKS) berbasis Learning Cycle 5E ),, sedangkan pada aspek sikap dan keterampilan tidak terdapat perbedaan

    Secreted Human Amyloid Precursor Protein Binds Semaphorin 3a and Prevents Semaphorin-Induced Growth Cone Collapse

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    The amyloid precursor protein (APP) is well known for giving rise to the amyloid-β peptide and for its role in Alzheimer's disease. Much less is known, however, on the physiological roles of APP in the development and plasticity of the central nervous system. We have used phage display of a peptide library to identify high-affinity ligands of purified recombinant human sAPPα695 (the soluble, secreted ectodomain from the main neuronal APP isoform). Two peptides thus selected exhibited significant homologies with the conserved extracellular domain of several members of the semaphorin (Sema) family of axon guidance proteins. We show that sAPPα695 binds both purified recombinant Sema3A and Sema3A secreted by transfected HEK293 cells. Interestingly, sAPPα695 inhibited the collapse of embryonic chicken (Gallus gallus domesticus) dorsal root ganglia growth cones promoted by Sema3A (Kd≤8·10−9 M). Two Sema3A-derived peptides homologous to the peptides isolated by phage display blocked sAPPα binding and its inhibitory action on Sema3A function. These two peptides are comprised within a domain previously shown to be involved in binding of Sema3A to its cellular receptor, suggesting a competitive mechanism by which sAPPα modulates the biological action of semaphorins

    Inflammation and lung injury in an ovine model of fluid resuscitated endotoxemic shock

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    Background Sepsis is a multi-system syndrome that remains the leading cause of mortality and critical illness worldwide, with hemodynamic support being one of the cornerstones of the acute management of sepsis. We used an ovine model of endotoxemic shock to determine if 0.9% saline resuscitation contributes to lung inflammation and injury in acute respiratory distress syndrome, which is a common complication of sepsis, and investigated the potential role of matrix metalloproteinases in this process. Methods Endotoxemic shock was induced in sheep by administration of an escalating dose of lipopolysaccharide, after which they subsequently received either no fluid bolus resuscitation or a 0.9% saline bolus. Lung tissue, bronchoalveolar fluid (BAL) and plasma were analysed by real-time PCR, ELISA, flow cytometry and immunohistochemical staining to assess inflammatory cells, cytokines, hyaluronan and matrix metalloproteinases. Results Endotoxemia was associated with decreased serum albumin and total protein levels, with activated neutrophils, while the glycocalyx glycosaminoglycan hyaluronan was significantly increased in BAL. Quantitative real-time PCR studies showed higher expression of IL-6 and IL-8 with saline resuscitation but no difference in matrix metalloproteinase expression. BAL and tissue homogenate levels of IL-6, IL-8 and IL-1β were elevated. Conclusions This data shows that the inflammatory response is enhanced when a host with endotoxemia is resuscitated with saline, with a comparatively higher release of inflammatory cytokines and endothelial/glycocalyx damage, but no change in matrix metalloproteinase levels

    Apnea of prematurity: from cause to treatment

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    Apnea of prematurity (AOP) is a common problem affecting premature infants, likely secondary to a “physiologic” immaturity of respiratory control that may be exacerbated by neonatal disease. These include altered ventilatory responses to hypoxia, hypercapnia, and altered sleep states, while the roles of gastroesophageal reflux and anemia remain controversial. Standard clinical management of the obstructive subtype of AOP includes prone positioning and continuous positive or nasal intermittent positive pressure ventilation to prevent pharyngeal collapse and alveolar atelectasis, while methylxanthine therapy is a mainstay of treatment of central apnea by stimulating the central nervous system and respiratory muscle function. Other therapies, including kangaroo care, red blood cell transfusions, and CO2 inhalation, require further study. The physiology and pathophysiology behind AOP are discussed, including the laryngeal chemoreflex and sensitivity to inhibitory neurotransmitters, as are the mechanisms by which different therapies may work and the potential long-term neurodevelopmental consequences of AOP and its treatment

    Outcome prediction with a social cognitive battery: a multicenter longitudinal study

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    The interest in social cognition in schizophrenia is justified by the relationship between deficits in these skills and negative functional outcomes. Although assessment batteries have already been described, there is no consensus about which measures are useful in predicting patient functioning or quality of life (QoL). We investigated a set of five measures of recognition of facial emotions, theory of mind (ToM), and empathy in a cohort of 143 patients with schizophrenia or schizoaffective disorder at inclusion and, amongst whom 79 were reassessed 1 year later. The distribution was satisfactory for the TREF (Facial Emotion Recognition Task), V-SIR (Versailles-Situational Intention Reading), and QCAE (Questionnaire of Cognitive and Affective Empathy). Internal consistency was satisfactory for the TREF, V-SIR, V-Comics (Versailles Intention Attribution Task), and QCAE. Sensitivity to change was acceptable for the TREF. The TREF and V-SIR showed a cross-sectional relationship with functioning beyond the clinical symptoms of schizophrenia but not beyond neurocognition. Moreover, the TREF and V-SIR at inclusion could not predict functioning one year later, whereas most neurocognitive and clinical dimensions at inclusion could. Finally, only affective QCAE showed a significant cross-sectional, but not longitudinal, association with QoL. In conclusion, the TREF had satisfactory psychometric properties and showed a cross-sectional, but not longitudinal, association with objective outcome measures, thus appearing to be reliable in clinical practice and research. The V-SIR also showed promising psychometric properties, despite a possible weakness to detect change. However, these measures should be interpreted within the context of the good predictive power of the neurocognitive and clinical status on the outcome.Sorbonne Universités à Paris pour l'Enseignement et la RechercheFondaMental-Cohorte

    Developing a proxy version of the Adult Social Care Outcome Toolkit (ASCOT)

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    Background: Social care-related quality of life is a key outcome indicator used in the evaluation of social care interventions and policy. It is not, however, always possible to collect quality of life data by self-report even with adaptations for people with cognitive or communication impairments. A new proxy-report version of the Adult Social Care Outcomes Toolkit (ASCOT) measure of social care-related quality of life was developed to address the issues of wider inclusion of people with cognitive or communication difficulties who may otherwise be systematically excluded. The development of the proxy-report ASCOT questionnaire was informed by literature review and earlier work that identified the key issues and challenges associated with proxy-reported outcomes. Methods: To evaluate the acceptability and content validity of the ASCOT-Proxy, qualitative cognitive interviews were conducted with unpaid carers or care workers of people with cognitive or communication impairments. The proxy respondents were invited to ‘think aloud’ while completing the questionnaire. Follow-up probes were asked to elicit further detail of the respondent’s comprehension of the format, layout and content of each item and also how they weighed up the options to formulate a response. Results: A total of 25 unpaid carers and care workers participated in three iterative rounds of cognitive interviews. The findings indicate that the items were well-understood and the concepts were consistent with the item definitions for the standard self-completion version of ASCOT with minor modifications to the draft ASCOT-Proxy. The ASCOT-Proxy allows respondents to rate the proxy-proxy and proxy-patient perspectives, which improved the acceptability of proxy report. Conclusions: A new proxy-report version of ASCOT was developed with evidence of its qualitative content validity and acceptability. The ASCOT-Proxy is ready for empirical testing of its suitability for data collection as a self-completion and/or interview questionnaire, and also evaluation of its psychometric properties

    Developing a proxy version of the Adult Social Care Outcome Toolkit (ASCOT)

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    Background: Social care-related quality of life is a key outcome indicator used in the evaluation of social care interventions and policy. It is not, however, always possible to collect quality of life data by self-report even with adaptations for people with cognitive or communication impairments. A new proxy-report version of the Adult Social Care Outcomes Toolkit (ASCOT) measure of social care-related quality of life was developed to address the issues of wider inclusion of people with cognitive or communication difficulties who may otherwise be systematically excluded. The development of the proxy-report ASCOT questionnaire was informed by literature review and earlier work that identified the key issues and challenges associated with proxy-reported outcomes. Methods: To evaluate the acceptability and content validity of the ASCOT-Proxy, qualitative cognitive interviews were conducted with unpaid carers or care workers of people with cognitive or communication impairments. The proxy respondents were invited to ‘think aloud’ while completing the questionnaire. Follow-up probes were asked to elicit further detail of the respondent’s comprehension of the format, layout and content of each item and also how they weighed up the options to formulate a response. Results: A total of 25 unpaid carers and care workers participated in three iterative rounds of cognitive interviews. The findings indicate that the items were well-understood and the concepts were consistent with the item definitions for the standard self-completion version of ASCOT with minor modifications to the draft ASCOT-Proxy. The ASCOT-Proxy allows respondents to rate the proxy-proxy and proxy-patient perspectives, which improved the acceptability of proxy report. Conclusions: A new proxy-report version of ASCOT was developed with evidence of its qualitative content validity and acceptability. The ASCOT-Proxy is ready for empirical testing of its suitability for data collection as a self-completion and/or interview questionnaire, and also evaluation of its psychometric properties

    Diagnosis of obstructive coronary artery disease using computed tomography angiography in patients with stable chest pain depending on clinical probability and in clinically important subgroups: meta-analysis of individual patient data

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    OBJECTIVETo determine whether coronary computed tomography angiography (CTA) should be performed in patients with any clinical probability of coronary artery disease (CAD), and whether the diagnostic performance differs between subgroups of patients.DESIGNProspectively designed meta-analysis of individual patient data from prospective diagnostic accuracy studies.DATA SOURCESMedline, Embase, and Web of Science for published studies. Unpublished studies were identified via direct contact with participating investigators.ELIGIBILITY CRITERIA FOR SELECTING STUDIESProspective diagnostic accuracy studies that compared coronary CTA with coronary angiography as the reference standard, using at least a 50% diameter reduction as a cutoff value for obstructive CAD. All patients needed to have a clinical indication for coronary angiography due to suspected CAD, and both tests had to be performed in all patients. Results had to be provided using 2x2 or 3x2 cross tabulations for the comparison of CTA with coronary angiography. Primary outcomes were the positive and negative predictive values of CTA as a function of clinical pretest probability of obstructive CAD, analysed by a generalised linear mixed model; calculations were performed including and excluding non-diagnostic CTA results. The no-treat/treat threshold model was used to determine the range of appropriate pretest probabilities for CTA. The threshold model was based on obtained post-test probabilities of less than 15% in case of negative CTA and above 50% in case of positive CTA. Sex, angina pectoris type, age, and number of computed tomography detector rows were used as clinical variables to analyse the diagnostic performance in relevant subgroups.RESULTSIndividual patient data from 5332 patients from 65 prospective diagnostic accuracy studies were retrieved. For a pretest probability range of 7-67%, the treat threshold of more than 50% and the no-treat threshold of less than 15% post-test probability were obtained using CTA. At a pretest probability of 7%, the positive predictive value of CTA was 50.9% (95% confidence interval 43.3% to 57.7%) and the negative predictive value of CTA was 97.8% (96.4% to 98.7%); corresponding values at a pretest probability of 67% were 82.7% (78.3% to 86.2%) and 85.0% (80.2% to 88.9%), respectively. The overall sensitivity of CTA was 95.2% (92.6% to 96.9%) and the specificity was 79.2% (74.9% to 82.9%). CTA using more than 64 detector rows was associated with a higher empirical sensitivity than CTA using up to 64 rows (93.4% v 86.5%, P=0.002) and specificity (84.4% v 72.6%, P<0.001). The area under the receiver-operating-characteristic curve for CTA was 0.897 (0.889 to 0.906), and the diagnostic performance of CTA was slightly lower in women than in with men (area under the curve 0.874 (0.858 to 0.890) v 0.907 (0.897 to 0.916), P<0.001). The diagnostic performance of CTA was slightly lower in patients older than 75 (0.864 (0.834 to 0.894), P=0.018 v all other age groups) and was not significantly influenced by angina pectoris type (typical angina 0.895 (0.873 to 0.917), atypical angina 0.898 (0.884 to 0.913), non-anginal chest pain 0.884 (0.870 to 0.899), other chest discomfort 0.915 (0.897 to 0.934)).CONCLUSIONSIn a no-treat/treat threshold model, the diagnosis of obstructive CAD using coronary CTA in patients with stable chest pain was most accurate when the clinical pretest probability was between 7% and 67%. Performance of CTA was not influenced by the angina pectoris type and was slightly higher in men and lower in older patients

    Changing trends in mastitis

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    <p>Abstract</p> <p>The global dairy industry, the predominant pathogens causing mastitis, our understanding of mastitis pathogens and the host response to intramammary infection are changing rapidly. This paper aims to discuss changes in each of these aspects. Globalisation, energy demands, human population growth and climate change all affect the dairy industry. In many western countries, control programs for contagious mastitis have been in place for decades, resulting in a decrease in occurrence of <it>Streptococcus agalactiae </it>and <it>Staphylococcus aureus </it>mastitis and an increase in the relative impact of <it>Streptococcus uberis </it>and <it>Escherichia coli </it>mastitis. In some countries, <it>Klebsiella </it>spp. or <it>Streptococcus dysgalactiae </it>are appearing as important causes of mastitis. Differences between countries in legislation, veterinary and laboratory services and farmers' management practices affect the distribution and impact of mastitis pathogens. For pathogens that have traditionally been categorised as contagious, strain adaptation to human and bovine hosts has been recognised. For pathogens that are often categorised as environmental, strains causing transient and chronic infections are distinguished. The genetic basis underlying host adaptation and mechanisms of infection is being unravelled. Genomic information on pathogens and their hosts and improved knowledge of the host's innate and acquired immune responses to intramammary infections provide opportunities to expand our understanding of bovine mastitis. These developments will undoubtedly contribute to novel approaches to mastitis diagnostics and control.</p
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