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1.
Ann Oncol ; 33(11): 1186-1199, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35988656

RESUMO

BACKGROUND: Germline variant evaluation in precision oncology opens new paths toward the identification of patients with genetic tumor risk syndromes and the exploration of therapeutic relevance. Here, we present the results of germline variant analysis and their clinical implications in a precision oncology study for patients with predominantly rare cancers. PATIENTS AND METHODS: Matched tumor and control genome/exome and RNA sequencing was carried out for 1485 patients with rare cancers (79%) and/or young adults (77% younger than 51 years) in the National Center for Tumor Diseases/German Cancer Consortium (NCT/DKTK) Molecularly Aided Stratification for Tumor Eradication Research (MASTER) trial, a German multicenter, prospective, observational precision oncology study. Clinical and therapeutic relevance of prospective pathogenic germline variant (PGV) evaluation was analyzed and compared to other precision oncology studies. RESULTS: Ten percent of patients (n = 157) harbored PGVs in 35 genes associated with autosomal dominant cancer predisposition, whereof up to 75% were unknown before study participation. Another 5% of patients (n = 75) were heterozygous carriers for recessive genetic tumor risk syndromes. Particularly, high PGV yields were found in patients with gastrointestinal stromal tumors (GISTs) (28%, n = 11/40), and more specifically in wild-type GISTs (50%, n = 10/20), leiomyosarcomas (21%, n = 19/89), and hepatopancreaticobiliary cancers (16%, n = 16/97). Forty-five percent of PGVs (n = 100/221) supported treatment recommendations, and its implementation led to a clinical benefit in 40% of patients (n = 10/25). A comparison of different precision oncology studies revealed variable PGV yields and considerable differences in germline variant analysis workflows. We therefore propose a detailed workflow for germline variant evaluation. CONCLUSIONS: Genetic germline testing in patients with rare cancers can identify the very first patient in a hereditary cancer family and can lead to clinical benefit in a broad range of entities. Its routine implementation in precision oncology accompanied by the harmonization of germline variant evaluation workflows will increase clinical benefit and boost research.


Assuntos
Neoplasias , Adulto Jovem , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Mutação em Linhagem Germinativa , Predisposição Genética para Doença , Estudos Prospectivos , Síndrome , Medicina de Precisão/métodos
2.
BMC Psychiatry ; 22(1): 430, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35752758

RESUMO

BACKGROUND: Virtual communities played an important role in mental health and well-being during the Covid-19 pandemic by providing access to others and thereby preventing loneliness. The pandemic has accelerated the urge for digital solutions for people with pre-existing mental health problems. So far, it remains unclear how the people concerned communicate with each other and benefit from peer-to-peer support on a moderated digital platform. OBJECTIVE: The aim of the project was to identify and describe the communication patterns and verbal expression of users on the inCLOUsiv platform during the first lockdown in 2020. METHODS: Discussions in forums and live chats on inCLOUsiv were analysed using text mining, which included frequency, correlation, n-gram and sentiment analyses. RESULTS: The communication behaviour of users on inCLOUsiv was benevolent and supportive; and 72% of the identified sentiments were positive. Users addressed the topics of 'corona', 'anxiety' and 'crisis' and shared coping strategies. CONCLUSIONS: The benevolent interaction between users on inCLOUsiv is in line with other virtual communities for Covid-19 and the potential for peer-to-peer support. Users can benefit from each other's experiences and support each other. Virtual communities can be used as an adjuvant to existing therapy, particularly in times of reduced access to local health services.


Assuntos
COVID-19 , Comunicação em Saúde , Controle de Doenças Transmissíveis , Mineração de Dados , Humanos , Saúde Mental , Pandemias , SARS-CoV-2
3.
Phys Rev Lett ; 126(18): 187801, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018790

RESUMO

By neutron spin echo spectroscopy, we have studied the center of mass motion of short tracer chains on the molecular length scale within a highly entangled polymer matrix. The center of mass mean square displacements of the tracers independent of their molecular weight is subdiffusive at short times until it has reached the size of the tube d; then, a crossover to Fickian diffusion takes place. This observation cannot be understood within the tube model of reptation, but is rationalized as a result of important interchain couplings that lead to cooperative chain motion within the entanglement volume ∼d^{3}. Thus, the cooperative tracer chain motions are limited by the tube size d. If the center of mass displacement exceeds this size, uncorrelated Fickian diffusion takes over. Compared to the prediction of the Rouse model we observe a significantly reduced contribution of the tracer's internal modes to the spectra corroborating the finding of cooperative rather than Rouse dynamics within d^{3}.

4.
Appl Opt ; 60(19): D43-D51, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263827

RESUMO

We present the inscription of narrow-linewidth fiber Bragg gratings (FBGs) into different types of multicore fibers (MCFs) using ultrashort laser pulses and the phase mask technique, which can act as notch filters. Such filters are required, e.g., to suppress light emitted by hydroxyl in the Earth's upper atmosphere, which disturbs ground-based observation of extraterrestrial objects in the near infrared. However, the inscription into a commercially available seven-core fiber showed a quite large core-to-core deviation of the resonance wavelength of up to 0.45 nm. Two options are presented to overcome this: first, we present the photo-treatment of the FBGs to tune the resonance wavelength, which allows for sufficient resonance shifts. Second, adapted MCFs containing 12 cores, arranged on a circle, are fabricated. For this, two different fabrication procedures were investigated, namely, the mechanical drilling of the preform for a rod-in-tube version as well as a stack-and-draw approach. Both adapted MCFs yielded significant improvements with core-to-core wavelength variations of the FBGs of only about 0.18 nm and 0.11 nm, respectively, sufficient to fulfill the requirements for astronomical filter applications as discussed above.

5.
Opt Express ; 28(24): 35682-35694, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379679

RESUMO

We present an innovative concept of a semi-aperiodic phase mask design that enables the realization of multi-notch fiber Bragg gratings (FBG). This design utilizes the overlap and interference of near-infrared ultrashort laser pulses diffracted by short sequenced phase mask sections, which not only allows for a highly stable and reproducible inscription of a large number of wavelength filters but also paves the way towards full aperiodic phase masks. The semi-aperiodic FBG inscribed by this phase mask enables versatile notch filters showing multiple non-equidistant resonances. Those filters target applications, for instance in ground-based telescopes, where a large number of hydroxyl emission lines emitted in the upper atmosphere at near-infrared wavelengths restrict the observation of faint extraterrestrial objects.

6.
Phys Rev Lett ; 125(23): 238004, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33337173

RESUMO

This work clarifies the self-similar dynamics of large polymer rings using pulsed-field gradient nuclear magnetic resonance and neutron spin echo spectroscopy. We find center of mass diffusion taking place in three dynamic regimes starting (i) with a strongly subdiffusive domain ⟨r^{2}(t)⟩_{com}∼t^{α} (0.4≤α≤0.65); (ii) a second subdiffusive region ⟨r^{2}(t)⟩_{com}∼t^{0.75} that (iii) finally crosses over to Fickian diffusion. While the t^{0.75} range previously has been found in simulations and was predicted by theory, we attribute the first to the effect of cooperative dynamics resulting from the correlation hole potential. The internal dynamics at scales below the elementary loop size is well described by ring Rouse motion. At larger scales the dynamics is self-similar and follows very well the predictions of the scaling models with preference for the self-consistent fractal loopy globule model.

7.
Eur J Neurol ; 27(6): 1039-1047, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32149450

RESUMO

BACKGROUND AND PURPOSE: We investigated the effectiveness of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS) patients with large vessel or distal occlusions and mild neurological deficits, defined as National Institutes of Health Stroke Scale scores < 6 points. METHODS: The primary efficacy outcome was 3-month functional independence (FI) [modified Rankin Scale (mRS) scores 0-2] that was compared between patients with and without IVT treatment. Other efficacy outcomes of interest included 3-month favorable functional outcome (mRS scores 0-1) and mRS score distribution at discharge and at 3 months. The safety outcomes comprised all-cause 3-month mortality, symptomatic intracranial hemorrhage (ICH), asymptomatic ICH and severe systemic bleeding. RESULTS: We evaluated 336 AIS patients with large vessel or distal occlusions and mild stroke severity (mean age 63 ± 15 years, 45% women). Patients treated with IVT (n = 162) had higher FI (85.6% vs. 74.8%, P = 0.027) with lower mRS scores at hospital discharge (P = 0.034) compared with the remaining patients. No differences were detected in any of the safety outcomes including symptomatic ICH, asymptomatic ICH, severe systemic bleeding and 3-month mortality. IVT was associated with higher likelihood of 3-month FI [odds ratio (OR), 2.19; 95% confidence intervals (CI), 1.09-4.42], 3-month favorable functional outcome (OR, 1.99; 95% CI, 1.10-3.57), functional improvement at discharge [common OR (per 1-point decrease in mRS score), 2.94; 95% CI, 1.67-5.26)] and at 3 months (common OR, 1.72; 95% CI, 1.06-2.86) on multivariable logistic regression models adjusting for potential confounders, including mechanical thrombectomy. CONCLUSIONS: Intravenous thrombolysis is independently associated with higher odds of improved discharge and 3-month functional outcomes in AIS patients with large vessel or distal occlusions and mild stroke severity. IVT appears not to increase the risk of systemic or symptomatic intracranial bleeding.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Administração Intravenosa , Idoso , Isquemia Encefálica/tratamento farmacológico , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Hemorragias Intracranianas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia , Terapia Trombolítica , Resultado do Tratamento
8.
J Chem Phys ; 152(5): 054901, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32035437

RESUMO

Investigations of polymer systems that rely on the interpretation of dynamical scattering results as, e.g., the structure factor S(Q, t) of single chains or chain sections may require the inclusion of effects, as described within the framework of the random phase approximation (RPA) for polymers. To do this in practice for the dynamic part of S(Q, t) beyond the initial slope is a challenge. Here, we present a method (and software) that allows a straightforward assessment of dynamical RPA effects and inclusion of these in the process/procedures of model fitting. Examples of applications to the interpretation of neutron spin-echo data multi-component polymer melts are shown.

9.
Aesthetic Plast Surg ; 44(3): 1014-1042, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32410196

RESUMO

BACKGROUND: The worldwide spread of a novel coronavirus disease (COVID-19) has led to a near total stop of non-urgent, elective surgeries across all specialties in most affected countries. In the field of aesthetic surgery, the self-imposed moratorium for all aesthetic surgery procedures recommended by most international scientific societies has been adopted by many surgeons worldwide and resulted in a huge socioeconomic impact for most private practices and clinics. An important question still unanswered in most countries is when and how should elective/aesthetic procedures be scheduled again and what kind of organizational changes are necessary to protect patients and healthcare workers when clinics and practices reopen. Defining manageable, evidence-based protocols for testing, surgical/procedural risk mitigation and clinical flow management/contamination management will be paramount for the safety of non-urgent surgical procedures. METHODS: We conducted a MEDLINE/PubMed research for all available publications on COVID-19 and surgery and COVID-19 and anesthesia. Articles and referenced literature describing possible procedural impact factors leading to exacerbation of the clinical evolution of COVID-19-positive patients were identified to perform risk stratification for elective surgery. Based on these impact factors, considerations for patient selection, choice of procedural complexity, duration of procedure, type of anesthesia, etc., are discussed in this article and translated into algorithms for surgical/anesthesia risk management and clinical management. Current recommendations and published protocols on contamination control, avoidance of cross-contamination and procedural patient flow are reviewed. A COVID-19 testing guideline protocol for patients planning to undergo elective aesthetic surgery is presented and recommendations are made regarding adaptation of current patient information/informed consent forms and patient health questionnaires. CONCLUSION: The COVID-19 crisis has led to unprecedented challenges in the acute management of the crisis, and the wave only recently seems to flatten out in some countries. The adaptation of surgical and procedural steps for a risk-minimizing management of potential COVID-19-positive patients seeking to undergo elective aesthetic procedures in the wake of that wave will present the next big challenge for the aesthetic surgery community. We propose a clinical algorithm to enhance patient safety in elective surgery in the context of COVID-19 and to minimize cross-contamination between healthcare workers and patients. New evidence-based guidelines regarding surgical risk stratification, testing, and clinical flow management/contamination management are proposed. We believe that only the continuous development and broad implementation of guidelines like the ones proposed in this paper will allow an early reintegration of all aesthetic procedures into the scope of surgical care currently performed and to prepare the elective surgical specialties better for a possible second wave of the pandemic. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Infecções por Coronavirus/prevenção & controle , Procedimentos Cirúrgicos Eletivos/métodos , Controle de Infecções/métodos , Pandemias/prevenção & controle , Segurança do Paciente , Pneumonia Viral/prevenção & controle , Cirurgia Plástica/métodos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico/métodos , Controle de Doenças Transmissíveis/organização & administração , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Gerenciamento Clínico , Estudos de Viabilidade , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Equipamento de Proteção Individual/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Cuidados Pós-Operatórios/métodos , Cuidados Pré-Operatórios/métodos , Fatores Sexuais
10.
Nervenarzt ; 91(10): 908-919, 2020 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-32894302

RESUMO

BACKGROUND: The guidelines of the German Society for Neurology regarding the diagnostics and treatment of acute ischemic stroke contain the general recommendation of treatment on a stroke unit (SU) and the use of recanalizing treatment (intravenous thrombolysis, IVT; mechanical thrombectomy, MT) in appropriate patients. The nationwide availability of all three components represents a large organizational and healthcare political challenge. OBJECTIVE: Updated nationwide analysis of treatment rates in Germany based on a regionalized evaluation. METHODS: Based on the patient's place of residence, nationwide data of all hospitalized patients were evaluated using the German diagnosis-related groups (DRG) statistics from 2018 and compared with previous years. The rates for SU treatment, IVT and MT in the 412 German regional districts were analyzed. The 412 regions were grouped according to the degree of urbanization. RESULTS: Nationwide, a total of 224,647 patient cases with a main diagnosis of acute ischemic stroke were treated in 1382 hospitals in Germany in 2018. Overall, relatively high treatment rates were determined (SU = 73.3%; IVT = 16.4%; MT = 6.5%). Only 10.2% of treatments in the SU were performed on a SU located at a hospital with no neurology department. The regionalized analysis showed large treatment ranges for all three therapeutic components, with significantly lower treatment rates in regions with a lower degree of urbanization (SU, IVT, MT rates: urban = 75.4%, 17.4%, 7.5% and rural = 67.1%; 15.4%, 5.3%, respectively). CONCLUSION: Hospitalized healthcare in Germany shows high treatment rates for both SU admission and acute recanalization treatment in patients with acute ischemic stroke; however, there is further optimization potential in rural regions.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/terapia , Fibrinolíticos/uso terapêutico , Alemanha/epidemiologia , Humanos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Trombectomia , Terapia Trombolítica , Resultado do Tratamento
11.
Phys Rev Lett ; 122(8): 088001, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30932610

RESUMO

A key ingredient within theories focusing on the rheology of entangled polymers is the way how the topological constraints of an entangled chain are lifted by unconstrained segments, i.e., how the constraining tube is dilated. This important question has been addressed by directly measuring the tube diameter d at the scale of the tube by neutron spin echo spectroscopy. The tube diameter d and plateau modulus G_{N}^{0} of highly entangled polyethylene oxide (PEO) chains of volume fraction c that are diluted by low molecular PEO show a concentration dependence d∝c^{a/2} and G_{N}^{0}∝c^{1+a} with an exponent a close to 4/3. This result allows the clear discrimination between different theoretical models that predict 4/3 or other values between 1 and 2 and provides an important ingredient to tube model theories.

12.
Acta Psychiatr Scand ; 140(5): 393-407, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31393996

RESUMO

OBJECTIVES: The question whether mental illness prevalence rates are increasing is a controversially debated topic. Epidemiological articles and review publications that look into this research issue are often compromised by methodological problems. The present study aimed at using a meta-analysis technique that is usually applied for the analysis of intervention studies to achieve more transparency and statistical precision. METHODS: We searched PubMed, PsycINFO, CINAHL, Google Scholar and reference lists for repeated cross-sectional population studies on prevalence rates of adult mental illness based on ICD- or DSM-based diagnoses, symptom scales and distress scales that used the same methodological approach at least twice in the same geographical region. The study is registered with PROSPERO (CRD42018090959). RESULTS: We included 44 samples from 42 publications, representing 1 035 697 primary observations for the first time point and 783 897 primary observations for the second and last time point. Studies were conducted between 1978 and 2015. Controlling for a hierarchical data structure, we found an overall global prevalence increase in odds ratio of 1.179 (95%-CI: 1.065-1.305). A multivariate meta-regression suggested relevant associations with methodological characteristics of included studies. CONCLUSIONS: We conclude that the prevalence increase in adult mental illness is small, and we assume that this increase is mainly related to demographic changes.


Assuntos
Saúde Global/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Humanos , Prevalência
13.
Anaesthesist ; 68(11): 785-800, 2019 11.
Artigo em Alemão | MEDLINE | ID: mdl-31555832

RESUMO

Multidrug-resistant pathogens often lead to treatment failure of antimicrobial regimens. After a period of imbalance between the occurrence/spread of resistance mechanisms and the development of new substances, some new substances have meanwhile been approved and many more are currently undergoing clinical testing. They are particularly effective against specific resistance mechanisms/pathogens and should be preserved for definitive treatment of an isolated pathogen. In the absence of alternatives reserve antibiotics, such as aztreonam and colistin have experienced a renaissance. They are again used in special infection scenarios and clinically tested in combination with new substances. Despite the introduction and development of new substances the building of resistance will at some time also render these (at least partially) ineffective. Therefore, their implementation must be carried out according to the antibiotic or infectious diseases stewardship.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Aztreonam/uso terapêutico , Colistina/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana
14.
Anaesthesist ; 68(10): 711-730, 2019 10.
Artigo em Alemão | MEDLINE | ID: mdl-31555833

RESUMO

The increase in resistant pathogens has long been a global problem. Complicated life-threatening infections due to multidrug-resistant pathogens (MRD) meanwhile occur regularly in intensive care medicine. An important and also potentially modifiable factor of the rapid spread of resistance is the irrational use of broad spectrum antibiotics in human medicine. In addition to many other resistance mechanisms, beta-lactamases play an important role in Gram-negative pathogens. They are not uncommonly the leading reason of difficult to treat infections and the failure of known routinely used broad spectrum antibiotics, such as cephalosporins, (acylamino)penicillins and carbapenems. Strategies for containment of MRDs primaríly target the rational use of antibiotics. In this respect interdisciplinary treatment teams, e.g. antibiotic stewardship (ABS) and infectious diseases stewardship (IDS) play a major role.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/efeitos dos fármacos , Carbapenêmicos/uso terapêutico , Cefalosporinas/uso terapêutico , Humanos , Penicilinas/uso terapêutico
15.
Anaesthesist ; 68(Suppl 1): 40-62, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29383395

RESUMO

The mortality of patients with sepsis and septic shock is still unacceptably high. An effective calculated antibiotic treatment within 1 h of recognition of sepsis is an important target of sepsis treatment. Delays lead to an increase in mortality; therefore, structured treatment concepts form a rational foundation, taking relevant diagnostic and treatment steps into consideration. In addition to the assumed infection and individual risks of each patient, local resistance patterns and specific problem pathogens must be taken into account during the selection of anti-infective treatment. Many pathophysiologic alterations influence the pharmacokinetics (PK) of antibiotics during sepsis. The principle of standard dosing should be abandoned and replaced by an individual treatment approach with stronger weighting of the pharmacokinetics/pharmacodynamics (PK/PD) index of the substance groups. Although this is not yet the clinical standard, prolonged (or continuous) infusion of ß­lactam antibiotics and therapeutic drug monitoring (TDM) can help to achieve defined PK targets. Prolonged infusion is sufficient without TDM, but for continuous infusion, TDM is generally necessary. A further argument for individual PK/PD-oriented antibiotic approaches is the increasing number of infections due to multidrug-resistant (MDR) pathogens in the intensive care unit. For effective treatment, antibiotic stewardship teams (ABS teams) are becoming more established. Interdisciplinary cooperation of the ABS team with infectious disease (ID) specialists, microbiologists, and clinical pharmacists leads not only to rational administration of antibiotics, but also has a positive influence on treatment outcome. The gold standards for pathogen identification are still culture-based detection and microbiologic resistance testing for the various antibiotic groups. Despite the rapid investigation time, novel polymerase chain reaction(PCR)-based procedures for pathogen identification and resistance determination are currently only an adjunct to routine sepsis diagnostics, due to the limited number of studies, high costs, and limited availability. In complicated septic courses with multiple anti-infective therapies or recurrent sepsis, PCR-based procedures can be used in addition to treatment monitoring and diagnostics. Novel antibiotics represent potent alternatives in the treatment of MDR infections. Due to the often defined spectrum of pathogens and the practically (still) absent resistance, they are suitable for targeted treatment of severe MDR infections (therapy escalation). (Contribution available free of charge by "Free Access" [ https://link.springer.com/article/10.1007/s00101-017-0396-z ].).


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Gestão de Antimicrobianos , Biomarcadores , Monitoramento de Medicamentos , Humanos , Unidades de Terapia Intensiva , Choque Séptico/tratamento farmacológico , beta-Lactamas/farmacocinética , beta-Lactamas/uso terapêutico
16.
Opt Lett ; 43(24): 6069-6072, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30548006

RESUMO

Diffraction gratings are transversally inscribed in the bulk of monolithic crystalline silicon with infrared nanosecond laser pulses. Nanoscale material analyses of the modifications composing the gratings show that they rely on laser-induced stress associated with a positive refractive index change as confirmed with phase-shift interferometry. Characterizations of the optical properties of the gratings, including the diffraction angles and the efficiency of the different orders, are carried out. The refractive index change obtained from these measurements is in good agreement with the phase-shift measurements. Finally, we show that the grating diffraction efficiency depends strongly on the laser writing speed.

17.
Phys Rev Lett ; 120(14): 144802, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29694120

RESUMO

Self-modulation of an electron beam in a plasma has been observed. The propagation of a long (several plasma wavelengths) electron bunch in an overdense plasma resulted in the production of multiple bunches via the self-modulation instability. Using a combination of a radio-frequency deflector and a dipole spectrometer, the time and energy structure of the self-modulated beam was measured. The longitudinal phase space measurement showed the modulation of a long electron bunch into three bunches with an approximately 200 keV/c amplitude momentum modulation. Demonstrating this effect is a breakthrough for proton-driven plasma accelerator schemes aiming to utilize the same physical effect.

19.
Anaesthesist ; 67(12): 936-949, 2018 12.
Artigo em Alemão | MEDLINE | ID: mdl-30511110

RESUMO

In January 2018 the recent revision of the S2k guidelines on calculated parenteral initial treatment of bacterial diseases in adults-update 2018 (Editor: Paul Ehrlich Society for Chemotherapy, PEG) was realized. It is a helpful tool for the complex infectious disease setting in an intensive care unit. The present summary of the guidelines focuses on the topics of anti-infective agents, including new substances, pharmacokinetics and pharmacodynamics as well as on microbiology, resistance development and recommendations for calculated drug therapy in septic patients. As in past revisions the recent resistance situation and results of new clinical studies are considered and anti-infective agents are summarized in a table.


Assuntos
Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Guias como Assunto , Humanos , Infusões Parenterais
20.
Anaesthesist ; 67(6): 461-476, 2018 06.
Artigo em Alemão | MEDLINE | ID: mdl-29766208

RESUMO

Sepsis-induced changes in pharmacokinetic parameters are a well-known problem in intensive care medicine. Dosing of antibiotics in this setting is therefore challenging. Alterations to the substance-specific kinetics of anti-infective substances have an effect on the distribution and excretion processes in the body. Increased clearance and an increased distribution volume (Vd) and particularly compromized organ function with reduced antibiotic elimination are often encountered in patients with sepsis. Renal replacement treatment, which is frequently used in intensive care medicine, represents a substantial intervention in this system. Current international guidelines recommend individualized dosing strategies and adaptation of doses according to measured serum levels and pharmacokinetic/pharmacodynamic (PK/PD) parameters as concepts to optimize anti-infective therapy in the critically ill. Likewise, the recommendation to adjust the administration form of beta-lactam antibiotics to prolonged or continuous infusion can be found increasingly more often in the literature. This article reviews the background of the individual dosing in intensive care patients and their applicability to the clinical routine.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Antibacterianos/farmacocinética , Cuidados Críticos , Monitoramento de Medicamentos , Humanos , Medicina de Precisão , Sepse/tratamento farmacológico , Sepse/metabolismo , Choque Séptico/tratamento farmacológico
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