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1.
BMC Psychol ; 11(1): 245, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626397

RESUMO

BACKGROUND: Stress-related disorders such as anxiety and depression are highly prevalent and cause a tremendous burden for affected individuals and society. In order to improve prevention strategies, knowledge regarding resilience mechanisms and ways to boost them is highly needed. In the Dynamic Modelling of Resilience - interventional multicenter study (DynaM-INT), we will conduct a large-scale feasibility and preliminary efficacy test for two mobile- and wearable-based just-in-time adaptive interventions (JITAIs), designed to target putative resilience mechanisms. Deep participant phenotyping at baseline serves to identify individual predictors for intervention success in terms of target engagement and stress resilience. METHODS: DynaM-INT aims to recruit N = 250 healthy but vulnerable young adults in the transition phase between adolescence and adulthood (18-27 years) across five research sites (Berlin, Mainz, Nijmegen, Tel Aviv, and Warsaw). Participants are included if they report at least three negative burdensome past life events and show increased levels of internalizing symptoms while not being affected by any major mental disorder. Participants are characterized in a multimodal baseline phase, which includes neuropsychological tests, neuroimaging, bio-samples, sociodemographic and psychological questionnaires, a video-recorded interview, as well as ecological momentary assessments (EMA) and ecological physiological assessments (EPA). Subsequently, participants are randomly assigned to one of two ecological momentary interventions (EMIs), targeting either positive cognitive reappraisal or reward sensitivity. During the following intervention phase, participants' stress responses are tracked using EMA and EPA, and JITAIs are triggered if an individually calibrated stress threshold is crossed. In a three-month-long follow-up phase, parts of the baseline characterization phase are repeated. Throughout the entire study, stressor exposure and mental health are regularly monitored to calculate stressor reactivity as a proxy for outcome resilience. The online monitoring questionnaires and the repetition of the baseline questionnaires also serve to assess target engagement. DISCUSSION: The DynaM-INT study intends to advance the field of resilience research by feasibility-testing two new mechanistically targeted JITAIs that aim at increasing individual stress resilience and identifying predictors for successful intervention response. Determining these predictors is an important step toward future randomized controlled trials to establish the efficacy of these interventions.


Assuntos
Resiliência Psicológica , Adolescente , Humanos , Adulto Jovem , Ansiedade , Transtornos de Ansiedade , Nível de Saúde , Saúde Mental , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Anaesthesia ; 75(12): 1620-1625, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32520406

RESUMO

Lung ultrasound could facilitate the triage of patients with suspected COVID-19 infection admitted to the emergency room. We developed a predictive model for COVID-19 diagnosis based on lung ultrasound and clinical features. We used ultrasound to image the lung bilaterally at two anterior sites, one and two hands below each clavicle, and a posterolateral site that was the posterior transverse continuation from the lower anterior site. We studied 100 patients, 31 of whom had a COVID-19 positive reverse transcriptase polymerase chain reaction. A positive test was independently associated with: quick sequential organ failure assessment score ≥1; ≥3 B-lines at the upper site; consolidation and thickened pleura at the lower site; and thickened pleura line at the posterolateral site. The model discrimination was an area (95%CI) under the receiver operating characteristic curve of 0.82 (0.75-0.90). The characteristics (95%CI) of the model's diagnostic threshold, applied to the population from which it was derived, were: sensitivity, 97% (83-100%); specificity, 62% (50-74%); positive predictive value, 54% (41-98%); and negative predictive value, 98% (88-99%). This model may facilitate triage of patients with suspected COVID-19 infection admitted to the emergency room.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Serviço Hospitalar de Emergência/estatística & dados numéricos , Pulmão/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Adulto , Idoso , Área Sob a Curva , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/diagnóstico , Serviços Médicos de Emergência , Serviço Hospitalar de Emergência/organização & administração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Pandemias , Pleura/diagnóstico por imagem , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Triagem , Ultrassonografia
4.
Math Biosci Eng ; 16(6): 8144-8161, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31698660

RESUMO

In this paper, the infinitesimal orbits around the libration points in the photogravitational oblate restricted problem are computed. To reach this goal, the Hamiltonian of our dynamical model taking into account the considered perturbing forces is constructed. A lie operator method, as a method of solution, is outlined. The Hamiltonian is transferred to any point of the equilibruim point as an origin. The explicit first order as well as the second order solutions for the coordinates and their conjugate momenta of a test particle in an infinitesimal orbit around any equilibrium point are obtained.

5.
Br J Anaesth ; 121(3): 534-540, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30115250

RESUMO

BACKGROUND: Dynamic arterial elastance (Eadyn) has been proposed as an indicator of vascular tone that predicts the decrease in arterial pressure in response to changes in norepinephrine (NE). The purpose of this study was to determine whether Eadyn measured by uncalibrated pulse contour analysis (UPCA) can predict a decrease in arterial pressure when the NE dosage is decreased. METHODS: We conducted a prospective study in a university hospital intensive care unit. Patients with vasoplegic syndrome for whom the intensive care physician planned to decrease the NE dosage were included. Haemodynamic and UPCA (VolumeView and FloTrac; Edwards Lifesciences, Irvine, CA, USA) values were obtained before and after decreasing the NE dosage. Responders were defined by a >10% decrease in mean arterial pressure (MAP). RESULTS: Of 35 patients included, 11 (31%) were pressure responders with a median decrease of 13%. Eadyn was correlated to systolic arterial pressure (SAP) (r=0.255; P=0.033), diastolic arterial pressure (r=0.271; P=0.024), MAP (r=0.310; P=0.009), heart rate (r=0.543; P=0.0001), and transthoracic echography cardiac output (r=0.264; P=0.024). Baseline Eadyn was correlated with MAP changes (r=0.394; P=0.019) and SAP changes (r=0.431; P=0.009). Eadyn predicted the decrease in arterial pressure with an area under the receiver-operating-characteristic curve of 0.84 (95% confidence interval: 0.70-0.97). The best cut-off was 0.90. CONCLUSIONS: The present study confirms the ability of Eadyn measured by UPCA to predict an arterial pressure response to a decrease in NE. Eadyn may constitute an easy-to-use functional approach to arterial tone assessment regardless of the monitor used to measure its determinant. CLINICAL TRIAL REGISTRATION: DRCIT95.


Assuntos
Pressão Arterial/efeitos dos fármacos , Norepinefrina/administração & dosagem , Análise de Onda de Pulso/métodos , Vasoconstritores/administração & dosagem , Vasoplegia/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Pressão Arterial/fisiologia , Cuidados Críticos/métodos , Relação Dose-Resposta a Droga , Elasticidade/efeitos dos fármacos , Elasticidade/fisiologia , Feminino , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Norepinefrina/farmacologia , Estudos Prospectivos , Vasoconstritores/farmacologia , Vasoplegia/fisiopatologia
7.
Cell Death Differ ; 23(4): 640-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26470725

RESUMO

Integrin α5ß1 expression is correlated with a worse prognosis in high-grade glioma. We previously unraveled a negative crosstalk between integrin α5ß1 and p53 pathway, which was proposed to be part of the resistance of glioblastoma to chemotherapies. The restoration of p53 tumor-suppressor function is under intensive investigations for cancer therapy. However, p53-dependent apoptosis is not always achieved by p53-reactivating compounds such as Nutlin-3a, although full transcriptional activity of p53 could be obtained. Here we investigated whether integrin α5ß1 functional inhibition or repression could sensitize glioma cells to Nutlin-3a-induced p53-dependent apoptosis. We discovered that α5ß1 integrin-specific blocking antibodies or small RGD-like antagonists in association with Nutlin-3a triggered a caspase (Casp) 8/Casp 3-dependent strong apoptosis in glioma cells expressing a functional p53. We deciphered the molecular mechanisms involved and we showed the crucial role of two anti-apoptotic proteins, phosphoprotein enriched in astrocytes 15 (PEA-15) and survivin in glioma cell apoptotic outcome. PEA-15 is under α5ß1 integrin/AKT (protein kinase B) control and survivin is a p53-repressed target. Moreover, interconnections between integrin and p53 pathways were revealed. Indeed PEA-15 repression by specific small-interfering RNA (siRNA)-activated p53 pathway to repress survivin and conversely survivin repression by specific siRNA decreased α5ß1 integrin expression. This pro-apoptotic loop could be generalized to several glioma cell lines, whatever their p53 status, inasmuch PEA-15 and survivin protein levels were decreased. Our findings identify a novel mechanism whereby inhibition of α5ß1 integrin and activation of p53 modulates two anti-apoptotic proteins crucially involved in the apoptotic answer of glioma cells. Importantly, our results suggest that high-grade glioma expressing high level of α5ß1 integrin may benefit from associated therapies including integrin antagonists and repressors of survivin expression.


Assuntos
Glioma/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Integrina alfa5beta1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Apoptose/genética , Proteínas Reguladoras de Apoptose , Astrócitos/metabolismo , Astrócitos/patologia , Linhagem Celular Tumoral , Glioma/genética , Glioma/patologia , Humanos , Proteínas Inibidoras de Apoptose/genética , Integrina alfa5beta1/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosfoproteínas/genética , Survivina , Proteína Supressora de Tumor p53/genética
8.
J Biomed Mater Res B Appl Biomater ; 94(2): 493-500, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20574974

RESUMO

Suture needles are essential instruments for performing blood vessel anastomosis in coronary artery bypass graft (CABG) surgeries. Exceptional needle performance is needed now as never before because of the increasing prevalence of elderly patients with advanced stages of coronary disease and calcified tissue. The various properties that affect the performance of suture needles used in CABG surgery are reviewed and recent progress towards improving needle performance through the use of tungsten-rhenium alloys and novel lubricous needle coatings is presented. Substantial enhancement of properties beyond those exhibited by commercially available stainless steel suture needles has been made, including an approximate 40% increase in strength, 100% increase in stiffness, and superior multiple pass penetration performance in both synthetic rubber media and human cadaver carotid arteries (p < 0.01).


Assuntos
Ponte de Artéria Coronária/instrumentação , Agulhas/normas , Rênio , Tungstênio , Humanos , Suturas
10.
J Forensic Sci ; 49(5): 935-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15461093

RESUMO

TATP in post explosion exhibits was reported earlier to be best recovered from vapor phase. A typical procedure includes its adsorption on Amberlite XAD-7, elution with acetonitrile and analysis by GC/MS. In this work, improved recovery of TATP from the vapor phase was achieved by SPME using PDMS/DVB fiber and immediate sampling to GC/MS. The recovery of TATP by SPME was compared with headspace and with adsorption on Amberlite XAD-7 by spiking onto filter paper put in a 100 mL beaker. The limit of detection of TATP was 6.4 ng in these conditions, few orders magnitude more than in the other tested methods. Recovery of TATP in the presence of various solvents was also studied. Acetone, water, and mixtures of water:alcohols (1:1) were found to reduce the recovery of TATP. Using SPME, TATP has been identified in dozens of post-explosion cases.


Assuntos
Explosões , Medicina Legal/métodos , Compostos Heterocíclicos com 1 Anel/análise , Peróxidos/análise , Acetona , Resinas Acrílicas , Adsorção , Resinas de Troca Aniônica , Dimetilpolisiloxanos , Etanol , Cromatografia Gasosa-Espectrometria de Massas , Metanol , Poliestirenos , Polivinil , Silicones , Solventes , Volatilização , Água
11.
Opt Lett ; 27(19): 1699-701, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18033340

RESUMO

Powerful green upconversion lasing of Er(3+):LiLuF(4) was achieved with a multipass pumping setup. The maximum output was 213 mW for Ti:sapphire laser pumping. Diode-pumped cw lasing at room temperature is demonstrated for the first time to the authors' knowledge.

12.
Klin Monbl Augenheilkd ; 216(4): 232-4, 2000 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-10820710

RESUMO

BACKGROUND: Foreign-body-reactions with granulomas after use of silicone-containing biomaterials are of clinical importance [4]. HISTORY AND SIGNS: A 4-year old patient entered our hospital with a reddish vascularised tumor. The tumor's origin was in the conjunctiva of the nasal lid-angle of the right eye. THERAPY AND OUTCOME: After a traumatic disconnection of the canaliculus lacrimalis inferior, a bicanalicular silicon-tube intubation had been performed with the patient in the age of one year. Only 3 years after this intervention a secondary clinical examination could be performed. At this time, an extended solid conjunctival-tumor appeared at the operated eye. After removal and histological examination it could be classified as a foreign body granuloma. CONCLUSIONS: The blood- and tissue compatibility of silicone is only insufficiently guaranteed on the basis of the hydrophobic material-surface. After reconstructive lacrimal surgery postoperative care and the removal of the stabilizing silicone material is necessary.


Assuntos
Doenças Palpebrais/patologia , Pálpebras/lesões , Reação a Corpo Estranho/patologia , Ducto Nasolacrimal/lesões , Complicações Pós-Operatórias/patologia , Elastômeros de Silicone , Stents , Pré-Escolar , Dacriocistorinostomia , Doenças Palpebrais/cirurgia , Pálpebras/patologia , Pálpebras/cirurgia , Feminino , Reação a Corpo Estranho/cirurgia , Humanos , Lactente , Obstrução dos Ductos Lacrimais/patologia , Ducto Nasolacrimal/patologia , Ducto Nasolacrimal/cirurgia , Complicações Pós-Operatórias/cirurgia , Reoperação
14.
Arch Biochem Biophys ; 350(1): 87-94, 1998 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9466824

RESUMO

Peroxidase active preparations from three Ancistrocladus species and from Triphyophyllum peltatum have been partially purified. They catalyze the oxidative dimerization of korupensamines A and B to michellamines A and C, respectively, as well as the mixed coupling to michellamines A, B, and C. All of these enzymes consist of single polypeptides of approximately 65 kDa with peroxidase activity as monomers. They were characterized as soluble proteins predominantly localized in the leaf phloem of all species examined. Comparative studies with various naphthol precursors revealed an unexpected substrate specificity. Only korupensamines were dimerized by the enzymes, while other monomers, even if closely related, were not accepted as substrates. The coupling reactions described here represent the first direct synthesis of michellamines from korupensamines without previous protection of these precursors.


Assuntos
Alcaloides/metabolismo , Fármacos Anti-HIV/metabolismo , Isoquinolinas/metabolismo , Magnoliopsida/enzimologia , Naftalenos/metabolismo , Peroxidases/metabolismo , Oxirredução , Especificidade da Espécie , Distribuição Tecidual
15.
Phytochemistry ; 47(1): 31-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9429317

RESUMO

From the as yet unexplored East African Liana, Ancistrocladus robertsoniorum, several naphthylisoquinoline alkaloids have been isolated, based mainly on High Speed Countercurrent Chromatography (HSCCC). The structure of the new compound, ancistrobertsonine A, was elucidated by chemical and spectroscopic methods. Furthermore, the known alkaloids ancistrocladine, its atropo-diastereomer, hamatine, and its regioisomer, ancistrobrevine B, were isolated.


Assuntos
Alcaloides/isolamento & purificação , Isoquinolinas/isolamento & purificação , Plantas/química , Alcaloides/química , Isoquinolinas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Estrutura Molecular
16.
Philos Trans R Soc Lond B Biol Sci ; 352(1358): 1191-202, 1997 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-9304686

RESUMO

To recognize a previously seen object, the visual system must overcome the variability in the object's appearance caused by factors such as illumination and pose. Developments in computer vision suggest that it may be possible to counter the influence of these factors, by learning to interpolate between stored views of the target object, taken under representative combinations of viewing conditions. Daily life situations, however, typically require categorization, rather than recognition, of objects. Due to the open-ended character of both natural and artificial categories, categorization cannot rely on interpolation between stored examples. Nonetheless, knowledge of several representative members, or prototypes, of each of the categories of interest can still provide the necessary computational substrate for the categorization of new instances. The resulting representational scheme based on similarities to prototypes appears to be computationally viable, and is readily mapped onto the mechanisms of biological vision revealed by recent psychophysical and physiological studies.


Assuntos
Cognição/fisiologia , Percepção de Forma/fisiologia , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão , Animais , Humanos , Reconhecimento Visual de Modelos/fisiologia , Primatas
17.
Neural Comput ; 9(4): 701-20, 1997 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9161020

RESUMO

A representational scheme under which the ranking between represented similarities is isomorphic to the ranking between the corresponding shape similarities can support perfectly correct shape classification because it preserves the clustering of shapes according to the natural kinds prevailing in the external world. This article discusses the computational requirements of representation that preserves similarity ranks and points out the relative straightforwardness of its connectionist implementation.


Assuntos
Percepção de Forma/fisiologia , Modelos Neurológicos , Visão Ocular/fisiologia , Humanos
18.
Int J Parasitol ; 27(1): 29-32, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9076526

RESUMO

Retarded development of exoerythrocytic stages of the rodent malaria parasite Plasmodium berghei in human hepatoma cells by extracts from Dioncophyllaceae and Ancistrocladaceae species. International Journal for Parasitology 27: 29-32. Naphthylisoquinoline alkaloid-containing extracts (10 micrograms ml-1) of species belonging to the Dioncophyllaceae and the Ancistrocladaceae, 2 small tropical plant families, display pronounced in vitro activities against exoerythrocytic stages of Plasmodium berghei (Anka), developing in human hepatoma cells (Hep G2). The highest activities were obtained with CH2Cl2 root and bark extracts, and a CH2Cl2/NH3 leaf extract from Triphyophyllum peltatum, a CH2Cl2/NH3 root extract from Ancistrocladus abbreviatus, and a CH2Cl2 leaf extract from A. tectorius. The degrees of growth inhibition ranged within 27.7-70.0%. The commercially available drug primaquine diphosphate (25 micrograms ml-1) caused a comparable effect (62.1%) in the same test system.


Assuntos
Antimaláricos/farmacologia , Malária/fisiopatologia , Extratos Vegetais/farmacologia , Plantas Medicinais , Plasmodium berghei/fisiologia , Animais , Carcinoma Hepatocelular , Linhagem Celular , Humanos , Neoplasias Hepáticas , Medicina Tradicional , Raízes de Plantas , Caules de Planta , Plasmodium berghei/efeitos dos fármacos , Roedores , Células Tumorais Cultivadas
19.
Symp Soc Exp Biol ; 46: 179-88, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1341034

RESUMO

The gene which is defective in Duchenne Muscular Dystrophy (DMD) extends over 2300 kb of the X chromosome. Its product in the muscle is a 14 kb mRNA encoding a 427 kd rod-shaped protein called dystrophin. A 14 kb transcript encoding a very similar isoform of dystrophin is produced in the brain. The brain 14 kb mRNA is transcribed from the same gene but controlled by a different promoter, located at least 75 kb upstream from the muscle dystrophin promoter. The regulation of these promoters is very stringently controlled. The muscle-type but not the brain-type dystrophin mRNA is found in cloned skeletal muscle cells and its presence is correlated with the appearance of multinucleated fibers. The brain type is expressed in neurons, while in glia cells the muscle-type promoter is active. A third DMD gene transcript which is only 6.5 kb long has been identified. It contains the sequence coding for the C-terminal domain and the cysteine-rich domain of dystrophin but not the large region encoding the spectrin-like repeats and the N-terminal domain. The cell type distribution of this transcript is also very different from that of the two 14 kb mRNA isoforms. It is the major product of the DMD gene in many nonmuscle tissues including brain. Using monoclonal antibodies we have identified a 77 Kd protein which seems to be the translation product of this mRNA. As expected from the distribution of the 6.5 Kb mRNA, this protein is the major DMD gene product detectable in brain and many other nonmuscle tissues; it is undetectable in skeletal muscle but is present in the heart and stomach (as is the 6.5 Kb mRNA).


Assuntos
Distrofina/genética , Distrofias Musculares/genética , Sequência de Bases , Química Encefálica , Humanos , Dados de Sequência Molecular , Músculos/química , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/análise
20.
Biochem J ; 272(2): 557-60, 1990 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-2176467

RESUMO

A novel transcript of the Duchenne muscular dystrophy gene has been identified. This 6.5 kb mRNA contains sequences from the 3' untranslated region of dystrophin mRNA and from the regions coding for the C-terminal and the cysteine-rich domains. However, probes for the regions encoding the spectrin-like repeats and the actin-binding domain, as well as probes for the first exons of the muscle- and brain-type dystrophin mRNA, did not hybridize with this new mRNA. Significant amounts of the 6.5 kb mRNA were found in a variety of non-muscle tissues, such as liver, testis, lung and kidney, but not in skeletal muscle. The abundance of this mRNA in the brain is at least as high as that of the previously described 14 kb brain-type dystrophin mRNA.


Assuntos
Distrofina/genética , Variação Genética , Músculos/metabolismo , Distrofias Musculares/genética , RNA Mensageiro/genética , Animais , Encéfalo/metabolismo , Carcinoma Hepatocelular , Linhagem Celular , Genes , Humanos , Neoplasias Hepáticas , Masculino , Hibridização de Ácido Nucleico , Especificidade de Órgãos , Splicing de RNA , Ratos , Espectrina/genética , Transcrição Gênica
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