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1.
Br J Surg ; 107(3): 171-190, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31916607

RESUMO

BACKGROUND: Umbilical and epigastric hernia repairs are frequently performed surgical procedures with an expected low complication rate. Nevertheless, the optimal method of repair with best short- and long-term outcomes remains debatable. The aim was to develop guidelines for the treatment of umbilical and epigastric hernias. METHODS: The guideline group consisted of surgeons from Europe and North America including members from the European Hernia Society and the Americas Hernia Society. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, the Scottish Intercollegiate Guidelines Network (SIGN) critical appraisal checklists, and the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument were used. A systematic literature search was done on 1 May 2018, and updated on 1 February 2019. RESULTS: Literature reporting specifically on umbilical and epigastric hernias was limited in quantity and quality, resulting in a majority of the recommendations being graded as weak, based on low-quality evidence. The main recommendation was to use mesh for repair of umbilical and epigastric hernias to reduce the recurrence rate. Most umbilical and epigastric hernias may be repaired by an open approach with a preperitoneal flat mesh. A laparoscopic approach may be considered if the hernia defect is large, or if the patient has an increased risk of wound morbidity. CONCLUSION: This is the first European and American guideline on the treatment of umbilical and epigastric hernias. It is recommended that symptomatic umbilical and epigastric hernias are repaired by an open approach with a preperitoneal flat mesh.

2.
Nature ; 577(7788): 47-51, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31894148

RESUMO

Phase separation is a cooperative process, the kinetics of which underpin the orderly morphogenesis of domain patterns on mesoscopic scales1,2. Systems of highly degenerate frozen states may exhibit the rare and counterintuitive inverse-symmetry-breaking phenomenon3. Proposed a century ago4, inverse transitions have been found experimentally in disparate materials, ranging from polymeric and colloidal compounds to high-transition-temperature superconductors, proteins, ultrathin magnetic films, liquid crystals and metallic alloys5,6, with the notable exception of ferroelectric oxides, despite extensive theoretical and experimental work on the latter. Here we show that following a subcritical quench, the non-equilibrium self-assembly of ferroelectric domains in ultrathin films of Pb(Zr0.4Ti0.6)O3 results in a maze, or labyrinthine pattern, featuring meandering stripe domains. Furthermore, upon increasing the temperature, this highly degenerate labyrinthine phase undergoes an inverse transition whereby it transforms into the less-symmetric parallel-stripe domain structure, before the onset of paraelectricity at higher temperatures. We find that this phase sequence can be ascribed to an enhanced entropic contribution of domain walls, and that domain straightening and coarsening is predominantly driven by the relaxation and diffusion of topological defects. Computational modelling and experimental observation of the inverse dipolar transition in BiFeO3 suggest the universality of the phenomenon in ferroelectric oxides. The multitude of self-patterned states and the various topological defects that they embody may be used beyond current domain and domain-wall-based7 technologies by enabling fundamentally new design principles and topologically enhanced functionalities within ferroelectric films.

3.
J Phys Chem A ; 123(46): 10057-10064, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31670512

RESUMO

Superfluid helium nanodroplets comprised of thousands to millions of helium atoms can serve as a reactor for the synthesis of heterogeneous molecular clusters at cryogenic conditions. The cluster synthesis occurs via consecutive pick-up of the cluster building blocks by the helium droplet and their subsequent coalescence within the droplet. The effective collision cross section of the building blocks is determined by the helium droplet size and thus exceeds by orders of magnitude that of a reactive collision in the gas phase. Moreover, the cryogenic helium environment (at 0.38 K) as a host promotes the formation of metastable cluster configurations. The question arises as to the extent of the actual involvement of the helium environment in the cluster formation. The present study deals with clusters of single phthalocyanine (Pc) molecules with single water molecules. A large fluorophore such as Pc offers several sites where the water molecule can attach. The resulting isomeric variants of the Pc-H2O complex can be selectively identified by electronic spectroscopy. We compare the experimental electronic spectra of the Pc-H2O complex generated in superfluid helium nanodroplets with the results of quantum-chemical calculations on the same cluster but under gas-phase conditions. The number of isomeric variants observed in the helium droplet experiment comes out the same as that obtained from our gas-phase calculations.

4.
Pneumologie ; 73(10): 586-591, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31622997

RESUMO

Infectious Diseases are a cross-sectional area connected to various medical disciplines and offer interested physicians multiple working opportunities. The spectrum of infectious diseases covers both out- and inpatient care as well as basic, clinical and epidemiological research. The need for infectious diseases specialists is increasing, thus career prospects are promising. Working conditions in infectious diseases are comparatively family-friendly. With this article we intend to arouse interest for working in the fascinating fields of infectious diseases and provide information on career opportunities. Data from a recently conducted survey among members of the German Society of Infectious Diseases deliver insight, how infectious disease specialists work today.


Assuntos
Escolha da Profissão , Infectologia/educação , Infectologia/organização & administração , Médicos , Estudos Transversais , Alemanha , Humanos , Médicos/organização & administração , Médicos/estatística & dados numéricos , Sociedades Médicas , Inquéritos e Questionários
5.
Nanoscale ; 11(41): 19190-19201, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31397835

RESUMO

The combination of computational chemistry and computational materials science with machine learning and artificial intelligence provides a powerful way of relating structural features of nanomaterials with functional properties. However, combining these fundamentally different scientific approaches is not as straightforward as it seems. Machine learning methods were developed for large data sets with small numbers of consistent features. Typically nanomaterials data sets are small, with high dimensionality and high variance in the feature space, and suffer from numerous destructive biases. None of the established data science or machine learning methods in widespread use today were devised with (nano)materials data sets in mind, but there are ways to overcome these challenges and use them reliably. In this review we will discuss domain-specific constraints on data-driven nanomaterials design, and explore the differences between nanomaterials simulation and nanoinformatics that can be leveraged for greater impact.

6.
Hernia ; 23(5): 969-977, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31420773

RESUMO

BACKGROUND: Due to the increased prevalence of overweight patients with ventral hernia, abdominal wall reconstruction combining ventral hernia repair (VHR) with panniculectomy (VHR-PAN) in overweight patients is increasingly considered. We present a retrospective comparison between VHR-PAN and VHR alone in overweight patients by examining costs, clinical outcomes, and quality of life (QoL). METHODS: Patients with body mass index (BMI) > 25.0 kg/m2 underwent VHR-PAN or VHR alone between September 2015 and May 2017 with a single surgeon and were matched into cohorts by BMI and age (n = 24 in each cohort). QoL was assessed using the Hernia-related Quality of Life Survey (HerQLes). Cost was assessed using billing data. Statistical analyses were performed using Fisher's exact tests, Mann-Whitney U tests, and regression modeling. RESULTS: Hernia defect size (p = 0.127), operative time (p = 0.140), mesh placement (p = 0.357), and recurrence rates (p = 0.156) did not vary significantly between cohorts at average follow up of one year. 60% of patients completed QoL surveys, with 61% net improvement in VHR-PAN postoperatively (p = 0.042) vs 36% in VHR alone (p = 0.054). Mean total hospitalization costs were higher for VHR alone (p = 0.019). Regression modeling showed no significant independent contribution of procedure performed due to differences in cost, wound complications, or hernia recurrence. CONCLUSIONS: At mean follow up of 2 years, VHR-PAN patients reported a comparable increase in QoL to those who received VHR alone without significantly different cost and complication rates. Concurrent VHR-PAN may therefore be a safe approach for overweight patients presenting with hernia and excess abdominal skin.

7.
Urologe A ; 58(10): 1179-1184, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31338523

RESUMO

Religion, which is one of the most important sources of human identity, has so far hardly been taken into account in the clinic. In the largely secularized society of Germany, this has played a highly subordinate role. Currently, however, the development towards a multireligious society is emerging, which will also be reflected in everyday medical care. Disease and mortality in patients can affect different cultural-religious spheres. Although distinction between cultural and religious aspects is possible, it is not necessary for clinical practice. In the situation of oncological therapy, questions may arise which must be answered differently in the religions Christianity, Judaism and Islam and which should be taken into account when selecting therapy. The consideration of cultural-religious rules can intensify the patient's acceptance, but it can also impair it in case of disregard. Such peculiarities can be the separation into male and female spheres or the restriction of certain auxiliary substances or drugs (blood products, narcotics). Kübler-Ross's phase model is suitable for determining where cultural-religious sensitivities should be taken into account in the phases of disease and how cultural-religious offerings can benefit the course of therapy. Due to large individual, regional, cultural and confessional differences, no systematic catalogue of procedures can be provided here. However, knowledge of such differences, more sensitive interaction with patients and their families and cooperation with hospital pastors can strengthen the relationship of trust between doctor and patient and thus improve the conditions for successful oncological therapy. These aspects should not be underestimated when treating people of other faiths in Germany's secular society.


Assuntos
Competência Cultural , Neoplasias/terapia , Religião e Medicina , Religião , Cristianismo , Feminino , Alemanha , Humanos , Islamismo , Judaísmo , Masculino , Neoplasias/etnologia , Neoplasias/psicologia , Espiritualidade
8.
Br J Dermatol ; 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31278741

RESUMO

Autosomal recessive epidermolytic ichthyosis is a rare skin condition associated with KRT10 loss-of-function mutations. It presents with severe life-threatening clinical manifestations. Here we describe a case of autosomal recessive epidermolytic ichthyosis with an unusually mild, spontaneously improving phenotype. Erythroderma and superficial blistering were present at birth, but the skin recovered and remained almost intact at the age of 1 year. Mild scaling on the neck and skin fragility manifesting as superficial erosions after scratching were the only clinical features as the child grew. As a cause, previously unreported compound heterozygous KRT10 pathogenic variants were found: a nonsense mutation leads to mRNA decay, while the other synonymous variant induces a leaky splice site, explaining the residual keratin 10 expression and mild clinical phenotype. What's already known about this topic? Autosomal recessive epidermolytic ichthyosis is a rare skin condition caused by loss-of-function KRT10 mutations. The clinical phenotype is severe with superficial skin blistering, scaling and hyperkeratosis. What does this study add? Here we extend the mutational and phenotypic spectrum of autosomal recessive epidermolytic ichthyosis. Our case presented with erythroderma and superficial blistering at birth, but the skin recovered and was almost intact at the age of 1 year. The only disease manifestations were mild scaling on the neck and skin fragility appearing as superficial erosions after scratching. The causative factors were found to be one nonsense mutation in KRT10 that leads to mRNA decay, and one synonymous variant that affects the donor splice site of exon 3. We hypothesize that this leaky splice site explains the residual keratin 10 expression and self-improving clinical phenotype.

11.
Health Phys ; 116(5): 727-735, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30747756

RESUMO

The identification of radiological sources by analysis of a gamma spectrum usually relies on the location of the set of radionuclide-specific electron energies corresponding to the incident photons interacting by photoelectric absorption in the detection medium. The challenge in low-level detection applications is the identification of these "photopeaks" above the background counts registered in the detector from the natural radiation environment and system noise. For source detection decisions, regions of the gamma spectrum other than at the photopeak energies may provide additional information about the presence of a source and allow for a higher rate of correct identification of a weak source. A statistical algorithm utilizing low-fidelity spectral data partitioned into three distinct regions and employing a binomial discriminator was tested in a laboratory setting against the traditional approach of source identification by exceeding a decision threshold within the photopeak region of interest. For an unshielded Cs source with no significant scatter between the source and the detector, the traditional peak identification method performs as well or better than most algorithm settings for various source strengths. However, an algorithm which also includes information in the energy range of Compton scattered photons provides improved detection capabilities for shielded weak sources. Such algorithms, including higher-fidelity developments, could be deployed to improve current tools for the search for orphan radiological sources and in the characterization of low-level environmental contamination.

12.
Hernia ; 23(2): 329-334, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30734888

RESUMO

PURPOSE: The penetration of hernia prevention techniques into surgical practice remains unknown. METHODS: A survey about knowledge/attitudes on hernia prevention was sent to the members of hernia societies. RESULTS: The 497 respondents were mostly from the US (47%) or Europe (40%). Most reported practicing, but not measuring their suture-to-wound length closure of > 4:1 (63%) and practicing but not measuring the number of stitches (58%). Reasons for not using short stitch closure were: does not apply to patient population (19%), not familiar enough with methods to correctly execute (25%), takes too long (13%), not reimbursed (4%), concerned about closure-related complications (27%), and other (22%). Regarding prophylactic mesh, respondents stated they were not familiar with literature (11%), familiar with literature but would not use (24%), familiar with literature and interested in use (45%), familiar with literature and using (15%), and other (5%). CONCLUSIONS: There appears to be some application of hernia prevention principles related to fascial closure; however, the use of prophylactic mesh still appears to be controversial.

13.
Science ; 363(6426): 516-521, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30705189

RESUMO

To provide an observational basis for the Intergovernmental Panel on Climate Change projections of a slowing Atlantic meridional overturning circulation (MOC) in the 21st century, the Overturning in the Subpolar North Atlantic Program (OSNAP) observing system was launched in the summer of 2014. The first 21-month record reveals a highly variable overturning circulation responsible for the majority of the heat and freshwater transport across the OSNAP line. In a departure from the prevailing view that changes in deep water formation in the Labrador Sea dominate MOC variability, these results suggest that the conversion of warm, salty, shallow Atlantic waters into colder, fresher, deep waters that move southward in the Irminger and Iceland basins is largely responsible for overturning and its variability in the subpolar basin.

14.
J Chem Phys ; 150(2): 024504, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30646699

RESUMO

In the present work, we employ broadband dielectric spectroscopy to study the molecular dynamics of the prototypical glass former glycerol confined in two microporous zeolitic imidazolate frameworks (ZIF-8 and ZIF-11) with well-defined pore diameters of 1.16 and 1.46 nm, respectively. The spectra reveal information on the modified α relaxation of the confined supercooled liquid, whose temperature dependence exhibits clear deviations from the typical super-Arrhenius temperature dependence of the bulk material, depending on the temperature and pore size. This allows assigning well-defined cooperativity length scales of molecular motion to certain temperatures above the glass transition. We relate these and previous results on glycerol confined in other host systems to the temperature-dependent length scale deduced from nonlinear dielectric measurements. The combined experimental data can be consistently described by a critical divergence of this correlation length as expected within theoretical approaches assuming that the glass transition is due to an underlying phase transition.

16.
Int J Cancer ; 144(1): 190-199, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30255938

RESUMO

Tyrosine kinase inhibitors (TKI) have improved prognosis in metastatic anaplastic lymphoma kinase (ALK)-driven lung adenocarcinoma, but patient outcomes vary widely. We retrospectively analyzed the clinical course of all cases with assessable baseline TP53 status and/or ALK fusion variant treated at our institutions (n = 102). TP53 mutations were present in 17/87 (20%) and the echinoderm microtubule-associated protein-like 4 (EML4)-ALK variant 3 (V3) in 41/92 (45%) patients. The number of metastatic sites at diagnosis was affected more by the presence of V3 than by TP53 mutations, and highest with both factors (mean 5.3, p < 0.001). Under treatment with ALK TKI, progression-free survival (PFS) was shorter with either TP53 mutations or V3, while double positive cases appeared to have an even higher risk (hazard ratio [HR] = 2.9, p = 0.015). The negative effect of V3 on PFS of TKI-treated patients was strong already in the first line (HR = 2.5, p = 0.037) and decreased subsequently, whereas a trend for PFS impairment under first-line TKI by TP53 mutations became stronger and statistically significant only when considering all treatment lines together. Overall survival was impaired more by TP53 mutations (HR = 4.9, p = 0.003) than by V3 (HR = 2.4, p = 0.018), while patients with TP53 mutated V3-driven tumors carried the highest risk of death (HR = 9.1, p = 0.02). Thus, TP53 mutations and V3 are independently associated with enhanced metastatic spread, shorter TKI responses and inferior overall survival in ALK+ lung adenocarcinoma. Both markers could assist selection of cases for more aggressive management and guide development of novel therapeutic strategies. In combination, they define a patient subset with very poor outcome.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Mutação , Proteínas de Fusão Oncogênica/genética , Proteína Supressora de Tumor p53/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Proteína Supressora de Tumor p53/metabolismo
17.
Br J Dermatol ; 180(4): 931-932, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30339730
18.
Br J Dermatol ; 180(3): 657-661, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30022487

RESUMO

Focal dermal hypoplasia (FDH, Goltz syndrome, MIM #305600) constitutes a rare multisystem genetic disorder of the skin, skeleton, teeth and eyes with considerable variation in the clinical features. FDH is transmitted as an X-linked dominant trait and is caused by mutations in PORCN. In male children, hemizygous PORCN mutations are lethal in utero. Around 300 cases have been reported in the literature to date. About 10% of them are male patients presenting with either Klinefelter syndrome (karyotype 47, XXY) or mosaicism of a postzygotic mutation. Here we describe four cases of women with typical features of FDH, in whom a PORCN mutation was found in DNA from affected cutaneous tissue but not in DNA from peripheral blood. This study suggests that mosaicism caused by a postzygotic mutation occurs more often than assumed to date in female patients with FDH. A negative analysis performed on peripheral blood DNA does not exclude the diagnosis of FDH and it is therefore of practical importance to analyse DNA from the affected skin in order to identify low-level mosaicism and thus to improve diagnostic precision. In total, we found two missense variants, one novel indel and one novel splice-site variant. Individuals harbouring postzygotic mosaicism run a risk of transmitting the disorder to their daughters, because the maternal mosaic could also affect the gonads.

19.
Br J Dermatol ; 180(2): 272-281, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30216406

RESUMO

These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016 and a consensus on the discussions. They summarize evidence and expert-based recommendations and are intended to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is part one, covering topical therapies, systemic therapies, psychosocial management, communicating the diagnosis and genetic counselling.

20.
Br J Dermatol ; 180(3): 484-495, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29897631

RESUMO

These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016, and a consensus on the discussions. These guidelines summarize evidence and expert-based recommendations and intend to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is part two, covering the management of complications and the particularities of some forms of congenital ichthyosis.

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