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1.
Faraday Discuss ; 245(0): 112-137, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37462069

RESUMO

The understanding of planet formation has changed recently, embracing the new idea of pebble accretion. This means that the influx of pebbles from the outer regions of planet-forming disks to their inner zones could determine the composition of planets and their atmospheres. The solid and molecular components delivered to the planet-forming region can be best characterized by mid-infrared spectroscopy. With Spitzer low-resolution (R = 100, 600) spectroscopy, this approach was limited to the detection of abundant molecules, such as H2O, C2H2, HCN and CO2. This contribution will present the first results of the MINDS (MIRI mid-INfrared Disk Survey, PI:Th Henning) project. Due do the sensitivity and spectral resolution provided by the James Webb Space Telescope (JWST), we now have a unique tool to obtain the full inventory of chemistry in the inner disks of solar-type stars and brown dwarfs, including also less-abundant hydrocarbons and isotopologues. The Integral Field Unit (IFU) capabilities will enable at the same time spatial studies of the continuum and line emission in extended sources such as debris disks, the flying saucer and also the search for mid-IR signatures of forming planets in systems such as PDS 70. These JWST observations are complementary to ALMA and NOEMA observations of outer-disk chemistry; together these datasets will provide an integral view of the processes occurring during the planet-formation phase.

2.
Nat Commun ; 10(1): 4470, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578321

RESUMO

The second plague pandemic, caused by Yersinia pestis, devastated Europe and the nearby regions between the 14th and 18th centuries AD. Here we analyse human remains from ten European archaeological sites spanning this period and reconstruct 34 ancient Y. pestis genomes. Our data support an initial entry of the bacterium through eastern Europe, the absence of genetic diversity during the Black Death, and low within-outbreak diversity thereafter. Analysis of post-Black Death genomes shows the diversification of a Y. pestis lineage into multiple genetically distinct clades that may have given rise to more than one disease reservoir in, or close to, Europe. In addition, we show the loss of a genomic region that includes virulence-related genes in strains associated with late stages of the pandemic. The deletion was also identified in genomes connected with the first plague pandemic (541-750 AD), suggesting a comparable evolutionary trajectory of Y. pestis during both events.


Assuntos
DNA Bacteriano/genética , Genoma Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Pandemias , Peste/epidemiologia , Yersinia pestis/genética , Arqueologia/métodos , DNA Bacteriano/química , DNA Bacteriano/classificação , Europa Oriental/epidemiologia , Fósseis , Humanos , Filogenia , Filogeografia , Peste/microbiologia , Polimorfismo de Nucleotídeo Único , Fatores de Tempo , Virulência/genética , Yersinia pestis/patogenicidade
3.
J Craniomaxillofac Surg ; 42(6): 852-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24444757

RESUMO

Early detection and complete resection of oral carcinomas is of crucial importance for patient survival. This could be significantly improved by developing a non-invasive, sensitive and real-time detection technique. Time-resolved autofluorescence measurement is state-of-the-art technology originally developed for non-destructive inspection of material. In this study, we measured time-resolved autofluorescence in tumours and healthy tissues of the oral cavity ex vivo and calculated the corresponding fractal dimension which was significantly higher in tumours than in healthy tissues (1.8 vs. 1.6, P < 0.001, unpaired t-test) with non-overlapping 95% confidential intervals 1.88-1.84 and 1.57-1.69, respectively. Very high specificity (86%) could be reached at 100% sensitivity. The area under the curve was 99%, further suggesting the superior prediction potential of fractal dimension based on time-resolved autofluorescence spectra.


Assuntos
Fractais , Mucosa Bucal/anatomia & histologia , Neoplasias Bucais/diagnóstico , Imagem Óptica/métodos , Área Sob a Curva , Carcinoma de Células Escamosas/diagnóstico , Detecção Precoce de Câncer , Fluorescência , Previsões , Humanos , Lasers , Sensibilidade e Especificidade , Espectrometria de Fluorescência/instrumentação , Fatores de Tempo
4.
Biosci Biotechnol Biochem ; 77(10): 2134-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24096648

RESUMO

We investigated the effects of a Eupatorium chinense var. simplicifolium (EUC) root extract on muscle disorders and explored the underlying mechanism for oxidative stress-induced C(2)C(12) myoblast damage. An EUC pre-treatment reduced the decreased cell viability after an H2O2 treatment. The heat shock protein (HSP) 70 level increased, and the phosphorylation of Jun amino-terminal kinases (JNKs) decreased in the EUC-pre-treated C(2)C(12) myoblasts. The results of the present study demonstrate the potential benefit of a herbal medicine in treating oxidative stress-related muscle disorders.


Assuntos
Apoptose/efeitos dos fármacos , Eupatorium/química , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Linhagem Celular , Mioblastos/metabolismo , Estresse Oxidativo/efeitos dos fármacos
5.
Med Eng Phys ; 35(7): 1015-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23127900

RESUMO

This study tested the effectiveness of low-level laser therapy (LLLT) in preventing and/or treating osteoporotic trabecular bone. Mice were ovariectomized (OVX) to induce osteoporotic bone loss. The tibiae of eight OVX mice were treated for 5 days each week for 2 weeks by LLLT (660 nm, 3 J) using a minimally invasive laser needle system (MILNS) which is designed to minimize loss of laser energy before reaching bone (LASER group). Another eight mice received a sham treatment (SHAM group). Structural parameters of trabecular bone were measured with in vivo micro-computed tomography images before and after laser treatment. After LLLT for 2 weeks, the percentage reduction (%R) was significantly lower in BV/TV (bone volume fraction) and Tb.N (trabecular number, p<0.05 and p<0.05) and significant higher in Tb.Sp (trabecular separation) and SMI (structure model index, p<0.05 and p<0.05) than in the SHAM group. The %R in BV/TV at sites directly treated by LLLT was significantly lower in the LASER group than the SHAM group (p<0.05, p<0.05). These results indicated that LLLT using MILNS may be effective for preventing and/or treating trabecular bone loss and the effect may be site-dependent in the same bone.


Assuntos
Terapia com Luz de Baixa Intensidade/instrumentação , Agulhas , Osteoporose/prevenção & controle , Osteoporose/radioterapia , Ovariectomia , Tíbia/efeitos da radiação , Animais , Feminino , Camundongos , Fatores de Tempo
6.
J Biomech ; 45(11): 2046-9, 2012 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-22663762

RESUMO

Mechanical loading is one of the determining factors for bone modulation, and is therefore frequently used to treat or prevent bone loss; however, there appears to be no data on the effects of baseline bone quantity on this response. This study aimed to verify whether baseline bone quantity affects osteoporotic trabecular bone adaptive response to mechanical stimulation. Twenty-four female Sprague-Dawley (SD) rats were ovariectomized (OVX). After 3 weeks of OVX, rats were divided into a high bone quantity and a low bone quantity group, and rats in each group were then subdivided into 4 groups that were exposed to different loading strategies. In the loading groups, tibiae were stimulated through axial loading at 2000µÎµ of strain, for 1500 cycles each of 75s, 150s, or 250s. The sham treatment groups received no loading. Changes in BV/TV for trabecular bone in the tibia were measured at the baseline (before loading), and at 3 weeks and 6 weeks after loading. BV/TVs in loading groups of the low baseline bone quantity group were significantly increased at 6 weeks, compared with those in the no-loading groups (p<0.05), while those in the high quantity groups were not increased (p>0.05). A significant negative correlation was observed between baseline BV/TV and its relative variations at 3 weeks or 6 weeks (p<0.05). These results indicate that adaptive responses of osteoporotic trabecular bone to mechanical loading depend on baseline bone quantity.


Assuntos
Osteoporose/fisiopatologia , Ovariectomia , Tíbia/fisiopatologia , Suporte de Carga , Animais , Força Compressiva , Módulo de Elasticidade , Feminino , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley
7.
Sudhoffs Arch ; 94(2): 214-42, 2010.
Artigo em Alemão | MEDLINE | ID: mdl-21322922

RESUMO

The article deals with the question of medicine in the time of the Nazi regime in Germany. It focuses on the question how the media in the "Third Reich" took up the subject "medicine" in general and which aspects were notably mentioned. The footing of this research is the "Westdeutscher Beobachter" and its local edition for the region and the city of Aachen. It was a newspaper published by the regional division of the NSDAP, hence a direct repetition of the Nazi ideology can be expected. During the research it became clear that medicine was not an important subject of propaganda in this newspaper. Only a few articles were about classic Nazi medical topics like "Erbgesundheit" (racial hygiene) and even less about naturopathy. The frequency of articles containing medical issues was very inconsistent, but only in 1934 there was a mentionable number of articles mostly concerning "Erbgesundheit". In this year the racial hygiene poured in law. The main consequence was the forced sterilization of over 300,000 people. Furthermore the topic "medicine" in general seems to be a marginal factor. More popular topics like economic or foreign policy dominated the report of the "Westdeutscher Beobachter". It seems to be that the emphasis was deliberately not laid on the matter "medicine" especially eugenics--which was one of the main components of the Nazi ideology--because the regime didn't want it to become a public interest.


Assuntos
Eugenia (Ciência)/história , Política de Saúde/história , Judeus/história , Socialismo Nacional/história , Jornais como Assunto/história , Alemanha , História do Século XX , Humanos
8.
J Biophotonics ; 2(10): 596-606, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19504515

RESUMO

Fluorescent cellular biomarkers play a prominent role in biosciences. Most of the available biomarkers have some drawbacks due to either physical and optical or cytotoxic properties. In view of this, we investigated the potential of green fluorescent nanodiamonds as biomarkers in living cells. Nanodiamonds were functionalized by attaching antibodies that target intracellular structures such as actin filaments and mitochondria. Then, the nanodiamond conjugates were transfected into HeLa cells. Transfections were mediated by 4(th)-generation dendrimers, cationic liposomes and protamine sulfate. Using fluorescence microscopy, we confirmed successful transfections of the nanodiamonds into HeLa cells. Nanodiamond fluorescence could be easily differentiated from cellular autofluorescence. Furthermore, nanodiamonds could be targeted selectively to intracellular structures. Therefore, nanodiamonds are a promising tool for intracellular assays.


Assuntos
Diamante/análise , Corantes Fluorescentes/análise , Imunoconjugados/química , Imunoconjugados/metabolismo , Mitocôndrias/metabolismo , Técnicas de Sonda Molecular , Nanopartículas/análise , Actinas/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Carbodi-Imidas/química , Dendrímeros/química , Diamante/química , Corantes Fluorescentes/química , Células HeLa , Humanos , Lipossomos/química , Microscopia de Fluorescência , Proteínas Mitocondriais/imunologia , Nanopartículas/química , Tamanho da Partícula , Protaminas/química , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Eletricidade Estática , Succinimidas/química , Propriedades de Superfície
9.
Eur Urol ; 55(2): 376-83, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18359147

RESUMO

OBJECTIVES: To determine the feasibility of ex situ prostate cancer detection by triple spectroscopy. A positive surgical margin following radical prostatectomy is an adverse factor for recurrence-free survival. Detection of residual cancer cells in vivo would be the most useful, allowing the resection of such tissue during the procedure. Aside from the use of frozen sections, the ability to detect positive surgical margins is limited. Laser-induced autofluorescence, white-light remission, and high-frequency impedance spectroscopy are methods that allow discrimination of tissues of different dignities based on their specific signature. We tested whether the combination of these techniques can differentiate malignant and benign prostate tissue ex vivo. MATERIALS AND METHODS: In preparation for future in vivo measurements, an ex vivo study was performed to detect characteristics of prostate tissue. Ninety-five tissue samples from 32 patients undergoing radical prostatectomy for clinically localized prostate cancer were taken immediately after removal of the prostate and stored in liquid nitrogen. Tissue samples were thawed for laser-induced autofluorescence, white-light remission, and high-frequency impedance spectroscopy. Based on these results, a computerized algorithm was developed for tissue differentiation. RESULTS: The statistical analysis of laser-induced autofluorescence and white-light remission data demonstrated a differentiation of benign and malignant prostate tissue with a sensitivity of 87.5% and a specificity of 87.3%. By adding the acquired high-frequency impedance data to the statistical analysis, sensitivity and specificity were increased to 93.8% and 92.4%. CONCLUSION: A highly accurate differentiation of prostate tissue was achieved in an ex vivo model. In vivo studies need to be performed to evaluate whether this technique can be successful in an intraoperative setting to detect positive surgical margins.


Assuntos
Neoplasias da Próstata/patologia , Análise Espectral/métodos , Algoritmos , Biópsia/métodos , Diferenciação Celular , Impedância Elétrica , Estudos de Viabilidade , Fluorescência , Humanos , Masculino , Valor Preditivo dos Testes , Próstata/patologia , Neoplasias da Próstata/cirurgia , Reprodutibilidade dos Testes
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