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Tuttle C, Boto J, Martin S, Barnaure I, Korchi AM, Scheffler M, Vargas MI. Neuroimaging of acute and chronic unilateral and bilateral thalamic lesions. Insights Imaging 2019; 10:24. [PMID: 30796553 PMCID: PMC6386756 DOI: 10.1186/s13244-019-0700-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 11/08/2018] [Indexed: 11/10/2022] Open
Abstract
The thalami are bilateral ovoid grey matter cerebral structures bordering the third ventricle on both sides, which participate in functions such as relaying of sensory and motor signals, regulation of consciousness, and alertness. Pathologies affecting the thalami can be of neoplastic, infectious, vascular, toxic, metabolic, or congenital origin.The purpose of this review is to provide a comprehensive approach to the thalamus focusing on its anatomy, the main pathologies affecting this structure and their radiological semiology on CT and MRI. We will also illustrate the importance of multimodal MR imaging (morphologic sequences, diffusion-weighted imaging, perfusion, spectroscopy) for the diagnosis and treatment of these conditions.
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Prendki V, Huttner B, Marti C, Mamin A, Fubini PE, Meynet MP, Scheffler M, Montet X, Janssens JP, Reny JL, Kaiser L, Garin N, Stirnemann J. Accuracy of comprehensive PCR analysis of nasopharyngeal and oropharyngeal swabs for CT-scan-confirmed pneumonia in elderly patients: a prospective cohort study. Clin Microbiol Infect 2019; 25:1114-1119. [PMID: 30641227 PMCID: PMC7172172 DOI: 10.1016/j.cmi.2018.12.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 12/18/2018] [Accepted: 12/22/2018] [Indexed: 01/19/2023]
Abstract
OBJECTIVES We aimed to assess the accuracy of PCR detection of viruses and bacteria on nasopharyngeal and oropharyngeal swabs (NPS) for the diagnosis of pneumonia in elderly individuals. METHODS We included consecutive hospitalized elderly individuals suspected of having pneumonia. At inclusion, NPS were collected from all participants and tested by PCR for the presence of viral and bacterial respiratory pathogens (index test, defined as comprehensive molecular testing). Routine diagnostic tests (blood and sputum culture, urine antigen detection) were also performed. The reference standard was the presence of pneumonia on a low-dose CT scan as assessed by two independent expert radiologists. RESULTS The diagnosis of pneumonia was confirmed in 127 of 199 (64%) included patients (mean age 83 years, community-acquired pneumonia in 105 (83%)). A pathogen was identified by comprehensive molecular testing in 114 patients (57%) and by routine methods in 22 (11%). Comprehensive molecular testing was positive for viruses in 62 patients (31%) and for bacteria in 73 (37%). The sensitivity and specificity were 61% (95% CI 53%-69%) and 50% (95% CI 39%-61%) for comprehensive molecular testing, and 14% (95% CI 82%-21%) and 94% (95% CI 86%-98%) for routine testing, respectively. Positive likelihood ratio was 2.55 for routine methods and 1.23 for comprehensive molecular testing. CONCLUSION Comprehensive molecular testing of NPS increases the number of pathogens detected compared with routine methods, but results are poorly predictive of the presence of pneumonia. Hence, comprehensive molecular testing is unlikely to impact clinical decision-making (NCT02467192). CLINICAL TRIALS REGISTRATION NCT02467192.
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Chabbert-Buffet N, Marret H, Agostini A, Cardinale C, Hamdaoui N, Hassoun D, Jonville-Bera AP, Lambert M, Linet T, Pienkowski C, Plu-Bureau G, Pragout D, Robin G, Rousset-Jablonski C, Scheffler M, Vidal F, Vigoureux S, Hédon B. [Contraception: CNGOF Guidelines for Clinical Practice (Short Version)]. ACTA ACUST UNITED AC 2018; 46:760-776. [PMID: 30416023 DOI: 10.1016/j.gofs.2018.10.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Indexed: 12/26/2022]
Abstract
The French College of Obstetrics and Gynecology (CNGOF) releases its first global recommendations for clinical practice in contraception, to provide physicians with an updated synthesis of available data as a basis for their practice. The French Health Authority (HAS) methodology was used. Twelve practical issues were selected by the organizing committee and the task force members. The available literature was screened until December 2017, and allowed the release of evidence-based, graded recommendations. This synthesis is issued from 12 developed texts, previously reviewed by experts and physicians from public and private practices, with an experience in the contraceptive field. Male and female sterilization, as well as the use of hormonal treatments without contraceptive label were excluded from the field of this analysis. Specific practical recommendations on the management of contraception prescription, patient information including efficacy, risks, and benefits of the different contraception methods, follow up, intrauterine contraception, emergency contraception, local and natural methods, contraception in teenagers and after 40, contraception in vascular high-risk situations, and in case of cancer risk are provided. The short/mid-term future of contraception mostly relies on improving the use of currently available methods. This includes reinforced information for users and increased access to contraception for women, whatever the social and clinical context. That is the goal of these recommendations.
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Nees J, Schott S, Schafferer S, Müller U, Rom J, Tang Q, Koal T, Wolf B, Scheffler M, Marmé F, Sohn C, Schneeweiss A, Burwinkel B. Identification of a blood based metabolomic classifer for the detection of ovarian cancer – MeDOC. Geburtshilfe Frauenheilkd 2018. [DOI: 10.1055/s-0038-1671309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Ohlmann C, Roger Z, Rüssel C, Hellmis E, Suttmann H, Janssen M, Hübner A, Dahm J, Gleißner J, Scheffler M, Feyerabend S, Telle J, Klier J. Abiraterone acetate plus prednisone and LHRH therapy versus abiraterone acetate plus prednisone while sparing LHRH therapy in patients with progressive, metastatic and chemotherapy-naïve, castration-resistant prostate cancer: Results from the SPARE-trial (NCT02077634). Ann Oncol 2018. [DOI: 10.1093/annonc/mdy284.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Salazar C, Baumann D, Hänke T, Scheffler M, Kühne T, Kaiser M, Voigtländer R, Lindackers D, Büchner B, Hess C. An ultra-high vacuum scanning tunneling microscope operating at sub-Kelvin temperatures and high magnetic fields for spin-resolved measurements. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:065104. [PMID: 29960518 DOI: 10.1063/1.5027782] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We present the construction and performance of an ultra-low-temperature scanning tunneling microscope (STM), working in ultra-high vacuum (UHV) conditions and in high magnetic fields up to 9 T. The cryogenic environment of the STM is generated by a single-shot 3He magnet cryostat in combination with a 4He dewar system. At a base temperature (300 mK), the cryostat has an operation time of approximately 80 h. The special design of the microscope allows the transfer of the STM head from the cryostat to a UHV chamber system, where samples and STM tips can be easily exchanged. The UHV chambers are equipped with specific surface science treatment tools for the functionalization of samples and tips, including high-temperature treatments and thin film deposition. This, in particular, enables spin-resolved tunneling measurements. We present test measurements using well-known samples and tips based on superconductors and metallic materials such as LiFeAs, Nb, Fe, and W. The measurements demonstrate the outstanding performance of the STM with high spatial and energy resolution as well as the spin-resolved capability.
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Kron A, Riedel R, Michels S, Fassunke J, Merkelbach-Bruse S, Scheffler M, Nogova L, Fischer R, Ueckeroth F, Abdulla D, Kron F, Pauli B, Kaminsky B, Braess J, Graeven U, Grohe C, Krueger S, Büttner R, Wolf J. Impact of co-occurring genomic alterations on overall survival of BRAF V600E and non-V600E mutated NSCLC patients: Results of the Network Genomic Medicine. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx380.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Riedel R, Kron A, Michels S, Fassunke J, Scheffler M, Fischer R, Nogova L, Abdulla D, Heydt C, Ueckeroth F, Pauli B, Serke M, Krueger S, Grohe C, Sebastian M, Koschel D, Kambartel KO, Zander T, Büttner R, Wolf J. Impact of next generation TKI and co-occurring mutations in ALK-positive NSCLC patients: Results of the Network Genomic Medicine. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx380.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Prendki V, Scheffler M, Garin N, Carballo S, Serratrice C, Marti C, Roux X, Serratrice J, Montet X, Reny J, Stirnemann J. Intérêt du scanner thoracique low-dose dans le diagnostic de la pneumonie du sujet âgé. Rev Med Interne 2017. [DOI: 10.1016/j.revmed.2017.03.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Kambartel K, Eggert J, Kopeika U, Liebisch P, Mlynek-Kersjes ML, Rösel C, Scheffler M, Yildirim A, Krbek T, Wolf J, Büttner R, Voshaar T. Erfolgreiche Therapie mit Afatinib und Crizotinib bei einer cMET-Amplifikation als Ursache einer sekundären EGFR-Resistenz. Pneumologie 2017. [DOI: 10.1055/s-0037-1598336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Koleczko S, Schäpers C, Scheffler M, Ihle M, Kostenko A, Michels S, Fischer R, Nogova L, Brandes V, Abdulla D, Ueckeroth F, Thurat M, Frank R, Eisert A, Bitter E, Wömpner C, Gogl L, Merkelbach-Bruse S, Büttner R, Wolf J. A comprehensive analysis of potentially targetable genetic aberrations and clinical findings in 821 patients with squamous-cell NSCLC – a comparison of NGM and TCGA LUSC data. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw383.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Nicholson EG, Schlegel C, Garofalo RP, Mehta R, Scheffler M, Mei M, Piedra PA. Robust Cytokine and Chemokine Response in Nasopharyngeal Secretions: Association With Decreased Severity in Children With Physician Diagnosed Bronchiolitis. J Infect Dis 2016; 214:649-55. [PMID: 27190183 PMCID: PMC4957440 DOI: 10.1093/infdis/jiw191] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 05/03/2016] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Bronchiolitis causes substantial disease in young children. Previous findings had indicated that a robust innate immune response was not associated with a poor clinical outcome in bronchiolitis. This study tested the hypothesis that increased concentrations of cytokines and chemokines in nasal wash specimens were associated with decreased severity in bronchiolitis. METHODS Children <24 months old who presented to the emergency department with signs and symptoms of bronchiolitis were eligible for enrollment. Nasal wash specimens were analyzed for viral pathogens and cytokine/chemokine concentrations. These results were evaluated with regard to disposition. RESULTS One hundred eleven children with bronchiolitis were enrolled. A viral pathogen was identified in 91.9% of patients (respiratory syncytial virus in 51.4%, human rhinovirus in 11.7%). Higher levels of cytokines and chemokines (interferon [IFN] γ; interleukin [IL] 4, 15, and 17; CXCL10; and eotaxin) were significantly associated with a decreased risk of hospitalization. IL-17, IL-4, IFN-γ, and IFN-γ-inducible protein 10 (CXCL10 or IP-10) remained statistically significant in the multivariate analyses. CONCLUSIONS The cytokines and chemokines significantly associated with decreased bronchiolitis severity are classified in a wide range of functional groups (T-helper 1 and 2, regulatory, and chemoattractant). The involvement of these functional groups suggest that a broadly overlapping cytokine/chemokine response is required for control of virus-mediated respiratory disease in young children.
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Ziemssen F, Hufenbach U, Wiedon A, Scheffler M, Bertelmann T. [Regional Differences in the Care of Patients with Neovascular Age-Related Macular Degeneration, Based on the Non-Interventional OCEAN Study]. Klin Monbl Augenheilkd 2016; 233:1367-1377. [PMID: 27454304 DOI: 10.1055/s-0042-100472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Background: The main cause of blindness in the elderly in Germany is neovascular age-related macular degeneration (nAMD). In the non-interventional OCEAN study, data were prospectively collected on the routine clinical care of patients treated with the drug ranibizumab. Patients: As part of an interim analysis within the ongoing study (NCT02194803), stratification was performed by the 17 regions of the German associations of panel physicians and by areas of different population density. Only data were analysed for patients for whom the first treatment with ranibizumab was documented. Results: A total of 5,606 patients were documented. The present manuscript reviews 2,658 treatment-naive patients with nAMD, documented by 324 ophthalmologists. Most patients receiving an intravitreal injection were female (60 %). The average patient was aged 77.7 ± 8.2 years at study start. The great majority of patients had statutory health insurance (91 %). At baseline, fluorescein angiography (FLA) was performed for 72 % of patients, while optical coherence tomography (OCT) was carried out for 76 %. A combination of both was performed for 54 % of patients, varying regionally from 26 % (Saxony-Anhalt) to 100 % (Berlin). The average waiting time between the first examination and the first injection was 20.0 ± 18.5 days. With different statistical models (ANOVA adjusted, with/without interactions), significant effects on treatment delay were found for district type (population density), federal state and type of specialist. Conclusion: No major regional differences were observed in the demographic characteristics of the patient population. The main regional disparities in the care of nAMD patients were in the application of diagnostic methods and the waiting times between the first examination and the first drug administration. The regional variations in treatment delays could clearly influence the risk of worse functional outcome.
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Clesse C, Lighezzolo-Alnot J, Hamlin S, De Lavergne S, Scheffler M. [The practice of episiotomy in France 10 years after the recommendations of CNGOF: What inventory?]. ACTA ACUST UNITED AC 2016; 44:232-8. [PMID: 26997462 DOI: 10.1016/j.gyobfe.2016.02.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 02/09/2016] [Indexed: 12/14/2022]
Abstract
Since its creation, the practice of episiotomy has evolved, being influenced by several factors. Various stances on its use were stated, until the eventual reduction of this practice, as suggested by numerous practical guides. In 2005, the National College of Obstetricians and Gynecologists in France published its French Guidelines for Clinical practice in this area. Today, it seems appropriate to focus on the evolution of the use of episiotomy, ten years after the publication of these recommendations. The authors propose a literature review, browsing through all the available epidemiological data in France related to episiotomy, recording all national statistics and some local trends, as there are regional specificities. This review allows to follow the overall evolution of the practice of episiotomy in France between 1981 and 2014, and to identify territorial disparities. Finally, in the specific context of the practice of episiotomy in French gynecological and obstetrics field, the authors conclude it by considering the possible evolution of this surgical practice, as well as, the Clinical Practice Recommendations related to it.
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Gogl L, Scheffler M, Ihle M, Michels S, Fischer R, Serke M, Gerigk U, Wömpner C, Krüger S, Kaminsky B, Schulte W, Höffken G, Merkelbach-Bruse S, Büttner R, Wolf J. 3131 Clinical and molecular characteristics of non-small cell lung cancer in patients harboring CTNNB1 mutations. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)31772-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ziemssen F, Bertelmann T, Hufenbach U, Scheffler M, Liakopoulos S, Schmitz-Valckenberg S. Verzögerung des Behandlungsbeginns um mehr als 2 Wochen. Ophthalmologe 2015. [DOI: 10.1007/s00347-015-0099-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Frank R, Scheffler M, Michels S, König K, Merkelbach-Bruse S, Serke M, Ko Y, Gerigk U, Geist T, Heukamp L, Büttner R, Wolf J. Occurrence and Characteristics of Keap1-Mutations in Patients with Non-Small Cell Lung Cancer (Nsclc). Ann Oncol 2014. [DOI: 10.1093/annonc/mdu349.93] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Michels S, Schultheis A, Scheffler M, Rosner T, Merkelbach-Bruse S, Heukamp L, Engel-Riedel W, Serke M, Krüger S, Benedikter J, Gerigk U, Schulte W, Draube A, Ko Y, Büttner R, Wolf J. Ret Translocation in Adenocarcinoma of the Lung. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu349.87] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Eisert A, Scheffler M, Michels S, Schultheis A, König K, Merkelbach-Bruse S, Serke M, Ko Y, Gerigk U, Geist T, Heukamp L, Büttner R, Wolf J. Genetic Variability and Clinical Presentation of Patients with Non-Small Cell Lung Cancer (Nsclc) Harboring Met-Amplifications. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu349.95] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Nogova L, Mattonet C, Scheffler M, Michels S, Bos M, Heukamp L, Schildhaus H, Fuhr U, Eberhardt W, Reis H, Wiesweg M, Schmid K, Schoch G, Serke M, Ko Y, Schuler M, Büttner R, Wolf J. Try - a Phase Ii Study to Evaluate Safety and Efficacy of Combined Trastuzumab and the Hsp90 Inhibitor Auy922 in Advanced Non-Small-Cell Lung Cancer (Nsclc) with Her2 Overexpression or Amplification or Mutation. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu349.17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Mehta R, Scheffler M, Tapia L, Aideyan L, Patel KD, Jewell AM, Avadhanula V, Mei M, Garofalo RP, Piedra PA. Lactate dehydrogenase and caspase activity in nasopharyngeal secretions are predictors of bronchiolitis severity. Influenza Other Respir Viruses 2014; 8:617-25. [PMID: 25132512 PMCID: PMC4262276 DOI: 10.1111/irv.12276] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2014] [Indexed: 01/19/2023] Open
Abstract
Background Bronchiolitis is the leading cause of hospitalization in infants. Biomarkers of disease severity might help in clinical management. Objective To determine the clinical predictiveness of NW-LDH, NW-caspase 3/7, and NW-LDH/NW-caspase 3/7 ratio in bronchiolitis. Methods Previously healthy children less than 24 months of age with bronchiolitis were recruited from the Texas Children's emergency room and intensive care unit from October 2010 to April 2011. Demographic, clinical information, and NW samples were obtained at enrollment. NW samples were analyzed for respiratory viruses, caspase 3/7, and LDH. Results A viral pathogen was detected in 91·6% of 131 children, with the most common being respiratory syncytial virus and human rhinovirus. A single infection was found in 61·8% of subjects and co-infection in 29·8%. Children admitted to ICU had significantly higher NW-LDH than children sent home from the ER or admitted to the general floor (P = 0·02). Children infected with RSV had the highest NW-LDH concentration (P = 0·03) compared with other viral infections. NW-LDH and NW-caspase were significantly correlated (r = 0·77, P < 0·0001). The univariate models showed NW-LDH and NW-LDH/NW- caspase 3/7 ratio were directly associated with hospitalization. Mutivariate regression analyses suggested a complex interaction between the biomarkers, demographics, and disposition. Conclusions NW-LDH, NW-caspase 3/7 and NW-LDH/NW-caspase 3/7 ratio and their interactions with demographic factors are predictive of bronchiolitis severity and can help distinguish children requiring ICU-level care from those admitted to the general floor, or discharged home from the emergency center.
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Zywietz T, Neugebauer J, Scheffler M, Northrup J, Van de Walle CG. Surface Structures, Surfactants and Diffusion at Cubic and Wurtzite GaN. ACTA ACUST UNITED AC 2014. [DOI: 10.1557/s1092578300000983] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Clean and As covered zinc-blende and wurtzite GaN surfaces have been investigated employing density-functional theory calculations. For clean GaN surfaces our calculations indicate the stability of several novel surface structures that are very different from those found on traditional III-V semiconductors. Adding impurities commonly present in significant concentrations during growth strongly modifies surface reconstructions and energies. In particular, we find that arsenic has a low solubility and significantly stabilizes the cubic GaN (001) surface making it interesting as a potential surfactant. Finally, we have studied the diffusion of Ga and N adatoms on both the equilibrium and non-equilibrium surfaces. Our calculations reveal a very different diffusivity for Ga and N adatoms: While Ga adatoms are very mobile at typical growth temperatures, the diffusion of N adatoms is slower by several orders of magnitude. These results give insight into the fundamental growth mechanisms and allow conclusions concerning optimum growth conditions.
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Scheffler M, Drawe H, Henglein A. Die Reaktionen des weißen Phosphors mit Dimethyldisulfid unter γ-Bestrahlung. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-1968-0705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Trimethylthiophosphite and red phosphorus are formed when solutions of white phosphorus in dimethyldisulfide are exposed to γ-radiation. The red phosphorus has a high content of CH3S groups. It is very reactive and can be converted into trimethylthiophosphite upon further irradiation in dimethyldisulfide suspension. Both the formation of red phosphorus from white phosphorus and the formation of trimethylthiophosphite from red phosphorus are chain processes. The radiation chemical yields are of the order of several 100 molecules/100 eV at room temperature.
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Scheffler M, Henglein A. Notizen: Über Kettenreaktionen bei der Auflösung von reaktivem Phosphor in Dimethyldisulfid unter Einfluß von γ-Strahlung. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-1970-0126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Chabbert-Buffet N, Guigues B, Trillot N, Biron C, Morange P, Pernod G, Scheffler M, Brugere S, Hedon B. [DVT and combined oral contraceptives: update of the pluridisciplinary CNGOF-FNCGM-GEHT-SFMV group]. J Gynecol Obstet Hum Reprod 2013; 42:309-315. [PMID: 23642503 DOI: 10.1016/j.jgyn.2013.03.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 06/02/2023]
Abstract
Thrombotic risk among combined oral contraceptives (COC) users has recently been debated following a court action initiated by a patient. Recent epidemiological data, as well as accumulating biological data underlying these data, have led French Health authorities to modify COC prescription and reimbursement modalities. A short synthesis is proposed by a multidisciplinary group of experts from four French societies (CGOF, FNCGM, GHT, and SFMV).
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