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1.
J Shoulder Elbow Surg ; 31(8): e369-e375, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35562030

RESUMO

BACKGROUND: Telemedicine has become a critical component in the evaluation and management of patients with shoulder pathology. However, the interobserver reliability of findings on virtual physical examination relative to in-person evaluation is unclear. The purpose of this study was to determine the reliability of prerecorded video telemedicine for the evaluation of shoulder pathology compared with traditional in-person physical examination. METHODS: New patients with unilateral shoulder pain presenting to a single-surgeon shoulder clinic were recruited between July and November 2020. In 1 visit, patients were evaluated with standardized in-person and video-guided telemedicine physical examinations in randomized order. Patients were evaluated for range of motion (ROM) and symptoms including pain, weakness, and apprehension. The telemedicine examination was recorded and consisted of a video guide displaying self-directed shoulder examination maneuvers that patients performed during remote coaching by an independent non-physician observer. The in-person physical examination was performed by the treating physician. The telemedicine videos were evaluated by two independent observers for interobserver reliability. The treating physician subsequently evaluated the telemedicine videos after a minimum two-month washout period for intraobserver reliability and intra-platform reliability. Interobserver and intraobserver reliability analyses were conducted using Kuder-Richardson formula 20 (KR-20). Specificity and likelihood ratios were calculated with P < .05 representing statistical significance. RESULTS: A total of 32 patients (17 male and 15 female patients; average age, 50.2 ± 16.2 years) were included in the analysis. Overall Kuder-Richardson formula 20 (KR-20) reliability across 40 physical examination maneuvers was 0.391 ± 0.332 (76.4% ± 15.4% agreement) between the in-person and telemedicine examinations. Telemedicine maneuvers examining ROM limitations had the highest degree of reliability, sensitivity, specificity, and likelihood of also producing a positive finding on the in-person examination (0.700 ± 0.114, 66.5%, 81.0%, and 6.06, respectively). Telemedicine maneuvers identifying apprehension associated with glenohumeral instability were found to have the lowest reliability, sensitivity, and likelihood of producing a positive finding on the in-person examination (0.170 ± 0.440, 23.5%, and 0.518, respectively). All patients were satisfied with their telemedicine experience. CONCLUSION: The overall reliability of a non-physician-directed video-guided telemedicine examination ranged from unacceptable to good. Shoulder ROM limitations identified during the telemedicine examinations were found to be the most reliable, whereas evaluations of instability were found to be the least reliable. Although initial telemedicine evaluation by a non-physician may be appropriate for ROM evaluation, in-person physician evaluation is recommended to confirm suspected diagnoses, especially if clinical concern for shoulder instability exists. Alternative methods of telemedicine delivery should be explored to improve the reliability of self-directed physical examination maneuvers.


Assuntos
Instabilidade Articular , Articulação do Ombro , Telemedicina , Adulto , Idoso , Feminino , Humanos , Instabilidade Articular/patologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Exame Físico/métodos , Reprodutibilidade dos Testes , Ombro , Articulação do Ombro/patologia , Dor de Ombro/diagnóstico , Telemedicina/métodos
2.
J Virol ; 93(3)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30429338

RESUMO

The impact of the Zika virus (ZIKV) epidemic highlights the need for vaccines that reduce or prevent infection and reliably prevent teratogenic complications. The live-attenuated measles virus (MV) vaccine strains are a promising vaccine platform, since they induce robust humoral and cellular immune responses against additional antigens and have an excellent safety record. To explore its potential to protect against ZIKV, we compared a recombinant Schwarz strain MV that encodes ZIKV prM and soluble E proteins (MV-Zika-sE) with a prototypic alum-adjuvanted whole inactivated ZIKV particle vaccine. Analysis of MV-Zika-sE-infected cells confirmed antigen expression, and the virus replicated with vaccine strain characteristics. Immunized IFNAR-/--CD46Ge mice developed E protein-specific and neutralizing antibodies, and ZIKV E-specific cellular immune responses were observed by gamma interferon (IFN-γ) enzyme-linked immunospot (ELISpot) and in vitro T cell proliferation assays. To analyze protective efficacy, vaccinated female mice were challenged with ZIKV after allogeneic mating. In MV-Zika-sE-vaccinated mice, weight gain was similar to that in uninfected mice, while no plasma viremia was detectable in the majority of the animals. In contrast, infected control animals gained less weight and experienced about 100-fold higher viremia over at least 3 days. Moreover, vaccination with MV-Zika-sE reduced the ZIKV load in different organs and the placentas and prevented infection of the fetus. Consequently, no fetal growth retardation, anemia, or death due to ZIKV infection was seen in MV-Zika-sE-vaccinated dams. In contrast, the inactivated ZIKV vaccine had little to no effect in our studies. Therefore, the MV-derived ZIKV vaccine is a promising candidate for further preclinical and clinical development.IMPORTANCE Zika virus (ZIKV) is a mosquito-borne flavivirus that causes a variety of neurological complications, including congenital birth defects. Despite the urgent need, no ZIKV vaccine has yet been licensed. Recombinant vaccine strain-derived measles viruses (MV) constitute a promising vector platform to induce immunity against foreign pathogens by expressing antigens from additional transcription units while at the same time possessing a remarkable safety profile. This concept has already been validated against different pathogens, including at least 3 other flaviviruses, and our data show that vaccination with MV expressing soluble ZIKV E protein significantly diminishes infection and prevents fetal loss or damage in an allogeneic mouse pregnancy model. It can thus be regarded as a promising emergency vaccine candidate with the potential for inclusion in routine vaccination settings in areas of endemicity to prevent teratogenic effects of circulating ZIKV during pregnancy, comparable to standard rubella virus vaccination.


Assuntos
Modelos Animais de Doenças , Vacina contra Sarampo/administração & dosagem , Vírus do Sarampo/imunologia , Proteínas do Envelope Viral/imunologia , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Animais , Anticorpos Antivirais/sangue , Feminino , Genoma Viral , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Vacina contra Sarampo/imunologia , Proteína Cofatora de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Gravidez , Receptor de Interferon alfa e beta/fisiologia , Vacinação , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Zika virus/genética , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
3.
Bioinformatics ; 34(4): 705-707, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29069312

RESUMO

Summary: PESTO is a widely applicable and highly customizable toolbox for parameter estimation in MathWorks MATLAB. It offers scalable algorithms for optimization, uncertainty and identifiability analysis, which work in a very generic manner, treating the objective function as a black box. Hence, PESTO can be used for any parameter estimation problem, for which the user can provide a deterministic objective function in MATLAB. Availability and implementation: PESTO is a MATLAB toolbox, freely available under the BSD license. The source code, along with extensive documentation and example code, can be downloaded from https://github.com/ICB-DCM/PESTO/. Contact: jan.hasenauer@helmholtz-muenchen.de. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , Software , Algoritmos
4.
J Allergy Clin Immunol ; 141(5): 1786-1798.e11, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28886863

RESUMO

BACKGROUND: Fusion proteins incorporating the Toll-like receptor 5 ligand flagellin are currently undergoing clinical trials as vaccine candidates for many diseases. OBJECTIVE: We studied the mechanisms of immune modulation by a flagellin:allergen fusion protein containing the Toll-like receptor 5 ligand flagellin A from Listeria monocytogenes and the birch pollen allergen Bet v 1 (recombinant flagellin A [rFlaA]:Betv1). METHODS: BALB/c mice were vaccinated with rFlaA:Betv1 in an experimental Bet v 1 sensitization model. Myeloid dendritic cells (mDCs) were differentiated from mouse bone marrow, and PBMCs were isolated from subjects with birch pollen allergy. Cells were stimulated with equimolar amounts of rFlaA, rBet v 1, rFlaA plus rBet v 1, or the rFlaA:Betv1 conjugate and analyzed for cell activation, cytokine secretion, and metabolic state. RESULTS: rFlaA:Betv1 displayed strong immune-modulating properties both in vivo and in vitro, as characterized by secretion of both proinflammatory and anti-inflammatory cytokines from murine mDCs and PBMCs from patients with birch allergy. rFlaA:Betv1 suppressed TH2 responses from Bet v 1-specific CD4+ T cells and prevented allergic sensitization in a mouse allergy model. Aggregation of rFlaA:Betv1 resulted in stronger protein uptake accompanied by an increased resistance to microsomal digestion. Remarkably, rFlaA:Betv1 induced activation of mammalian target of rapamycin, which increased the metabolic activity of the stimulated mDCs. rFlaA:Betv1-mediated IL-10 secretion, but not proinflammatory cytokine secretion, was inhibited by rapamycin in mDCs. CONCLUSION: These results provide evidence that mammalian target of rapamycin is a key player involved in prevention of TH2 responses by flagellin A conjugate vaccines.


Assuntos
Alérgenos/imunologia , Flagelina/imunologia , Interleucina-10/imunologia , Rinite Alérgica Sazonal/imunologia , Serina-Treonina Quinases TOR/imunologia , Animais , Antígenos de Plantas/imunologia , Betula/imunologia , Medula Óssea/imunologia , Linfócitos T CD4-Positivos , Citocinas/imunologia , Células Dendríticas , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pólen/imunologia , Proteínas Recombinantes/imunologia , Células Th2/imunologia , Receptor 5 Toll-Like/imunologia
5.
NPJ Vaccines ; 8(1): 46, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964176

RESUMO

A novel Influenza A virus (subtype H7N9) emerged in spring 2013 and caused considerable mortality in zoonotically infected patients. To be prepared for potential pandemics, broadly effective and safe vaccines are crucial. Recombinant measles virus (MeV) encoding antigens of foreign pathogens constitutes a promising vector platform to generate novel vaccines. To characterize the efficacy of H7N9 antigens in a prototypic vaccine platform technology, we generated MeVs encoding either neuraminidase (N9) or hemagglutinin (H7). Moraten vaccine strain-derived vaccine candidates were rescued; they replicated with efficiency comparable to that of the measles vaccine, robustly expressed H7 and N9, and were genetically stable over 10 passages. Immunization of MeV-susceptible mice triggered the production of antibodies against H7 and N9, including hemagglutination-inhibiting and neutralizing antibodies induced by MVvac2-H7(P) and neuraminidase-inhibiting antibodies by MVvac2-N9(P). Vaccinated mice also developed long-lasting H7- and N9-specific T cells. Both MVvac2-H7(P) and MVvac2-N9(P)-vaccinated mice were protected from lethal H7N9 challenge.

6.
Front Immunol ; 14: 1136669, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37026001

RESUMO

Background: A recombinant fusion protein combining the adjuvant and TLR5-ligand flagellin with the major birch pollen allergen Bet v 1 (rFlaA:Betv1) has been suggested to prevent the manifestation of birch allergy. Noteworthy, rFlaA:Betv1 induced both pro- and anti-inflammatory responses which were differentially regulated. However, the mechanism by which flagellin fusion proteins modulate allergen-specific immune responses, especially the mechanisms underlying IL-1ß secretion and their contribution to the overall immune responses remains elusive. Objective: To investigate the mechanisms underlying the production of IL-1ß from rFlaA:Betv1 stimulated macrophages. Methods: Macrophages were derived from mouse peritoneal-, human buffy-coat-, and PMA-differentiated THP-1 (wild type or lacking either ASC, NLRP3, or NLRC4) cells. Macrophages were stimulated with non-modified rFlaA:Betv1, mutant variants lacking either the flagellin DC0 domain or a sequence motif formerly described to mediate TLR5-activation, and respective controls in the presence or absence of inhibitors interfering with MAPK- and NFκB-signaling. Cytokine secretion was analyzed by ELISA and intracellular signaling by Western Blot. To study the contribution of IL-1ß to the overall immune responses, IL1R-deficient mouse peritoneal macrophages were used. Results: rFlaA:Betv1 consistently activated all types of investigated macrophages, inducing higher IL-1ß secretion compared with the equimolar mixture of both proteins. rFlaA:Betv1-induced activation of THP-1 macrophages was shown to be independent of either the TLR5-activating sequence motif or the flagellin DC0 domain but depended on both NLRP3- and NLRC4-inflammasomes. In addition, NFκB and SAP/JNK MAP kinases regulated rFlaA:Betv1-induced inflammasome activation and cytokine secretion by modulating pro-Caspase-1- and pro-IL-1ß-expression in THP-1 macrophages. Finally, lack of IL-1ß positive feedback via the IL1R strongly diminished the rFlaA:Betv1-induced secretion of IL-1ß, IL-6, and TNF-α from peritoneal macrophages. Conclusion: The mechanisms contributing to rFlaA:Betv1-induced IL-1ß secretion from macrophages were shown to be complex, involving both NLRC4- and NLRP3-inflammsomes, as well as NFκB- and SAP/JNK MAP kinase-signaling. Better understanding the mechanisms regulating the activation of immune cells by novel therapeutic candidates like the rFlaA:Betv1 fusion protein will allow us to further improve and develop new treatment strategies when using flagellin as an adjuvant.


Assuntos
Flagelina , Inflamassomos , Animais , Humanos , Camundongos , Adjuvantes Imunológicos/farmacologia , Alérgenos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Inflamassomos/metabolismo , Macrófagos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Recombinantes , Receptor 5 Toll-Like/metabolismo
7.
Geburtshilfe Frauenheilkd ; 82(6): 610-618, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35903717

RESUMO

Background Intraoperative frozen section analysis (FSA) of sentinel lymph nodes (SLNs) declined in the post American College of Surgeons Oncology Group Z0011 (ACOSOG Z0011) trial era. However, for those patients who do not meet the ACOSOG Z0011 criteria, FSA continues to be a valuable tool in intraoperative decision-making for axillary lymph node dissection (ALND). The aim of this study was therefore to retrospectively evaluate the benefit and accuracy of FSA of Z0011 criteria eligible versus ineligible patients and identify possible predictive factors for false negative results. Methods Intraoperative FSA was performed on SLNs of 522 cT1-T3 breast cancer patients between 2008 and 2013. Clinicopathologic characteristics were retrospectively assessed by chart review. Results Overall FSA sensitivity and specificity was 67.8% and 100%. Sensitivity was generally higher for macrometastasis than for micrometastasis. The Z0011 eligible group showed a sensitivity and specificity of 72.7% and 100% versus 62.1% and 100% in the Z0011 ineligible group. Importantly, subgroup analysis of ≤ 2 versus > 2 positive SLNs of the Z0011 eligible group demonstrated both a 100% specificity and sensitivity. Several clinicopathologic factors were associated with a higher rate of false negative results in the Z0011 ineligible patient group. FSA was beneficial for 22.2% of Z0011 ineligible patients and for only 0.6% of Z0011 eligible patients regarding intraoperative decision-making for ALND. Conclusions FSA continues to be especially beneficial in the intraoperative assessment of SLNs in the Z0011 ineligible group to prevent second stage ALND. Despite an overall lower FSA sensitivity in the Z0011 eligible patient group, FSA offers in both groups a comparable high sensitivity and diagnostic accuracy for macrometastasis.

8.
Cells ; 10(10)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34685593

RESUMO

TLR5 ligand flagellin-containing fusion proteins are potential vaccine candidates for many diseases. A recombinant fusion protein of flagellin A and the major birch pollen allergen Bet v 1 (rFlaA:Betv1) modulates immune responses in vitro and in vivo. We studied the effects of rFlaA:Betv1 on bone marrow-derived macrophages (BMDMs). BMDMs differentiated from BALB/c, C57BL/6, TLR5-/-, or MyD88-/- mice were pre-treated with inhibitors, stimulated with rFlaA:Betv1 or respective controls, and analyzed for activation, cytokine secretion, metabolic state, RNA transcriptome, and modulation of allergen-specific Th2 responses. Stimulation of BMDMs with rFlaA:Betv1 resulted in MyD88-dependent production of IL-1ß, IL-6, TNF-α, IL-10, CD69 upregulation, and a pronounced shift towards glycolysis paralleled by activation of MAPK, NFκB, and mTOR signaling. Inhibition of either mTOR (rapamycin) or SAP/JNK-MAPK signaling (SP600125) resulted in dose-dependent metabolic suppression. In BMDM and T cell co-cultures, rFlaA:Betv1 stimulation suppressed rBet v 1-induced IL-5 and IL-13 secretion while inducing IFN-γ production. mRNA-Seq analyses showed HIF-1a, JAK, STAT, phagosome, NLR, NFκB, TNF, TLR, and chemokine signaling to participate in the interplay of cell activation, glycolysis, and immune response. rFlaA:Betv1 strongly activated BMDMs, resulting in MyD88-, MAPK-, and mTOR-dependent enhancement of glucose metabolism. Our results suggest macrophages are important target cells to consider during restauration of allergen tolerance during AIT.


Assuntos
Alérgenos/imunologia , Antígenos de Bactérias/imunologia , Antígenos de Plantas/imunologia , Flagelina/imunologia , Proteínas Recombinantes de Fusão/imunologia , Animais , Proteínas de Bactérias/imunologia , Células Cultivadas , Glucose/metabolismo , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Plantas/imunologia , Pólen/imunologia
9.
ACS Appl Bio Mater ; 2(9): 4027-4036, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-35021336

RESUMO

Medical implants of polypropylene (PP) are commonly used in many surgical procedures to support tissues. Previous studies on polypropylene meshes removed from patients demonstrated biodegradation relative to the amount of time after implantation. Among the many possible factors, bacterial colonization is believed to be one of the causes for the biodegradation of PP. To gain insights on this hypothesis, PP mesh samples were tested in Luria-Bertani broth (LB) media containing Escherichia coli (E. coli) to observe possible degradation in a controlled single-organism environment. Mesh samples were immersed in either an LB media with E. coli or a control solution, and the biodegradation was measured at 1-, 2-, and 3-month intervals. The samples were then harvested from both LB media with E. coli and the control media for analysis, and results were then compared with pristine polypropylene mesh. The experimental results demonstrate qualitative and quantitative bioerosion, increased oxygen content, and enhanced hydrophilicity over the surface of the mesh structure, thus confirming the oxidative degradation in vitro.

10.
Nat Biotechnol ; 37(4): 461-468, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30936567

RESUMO

Recent single-cell RNA-sequencing studies have suggested that cells follow continuous transcriptomic trajectories in an asynchronous fashion during development. However, observations of cell flux along trajectories are confounded with population size effects in snapshot experiments and are therefore hard to interpret. In particular, changes in proliferation and death rates can be mistaken for cell flux. Here we present pseudodynamics, a mathematical framework that reconciles population dynamics with the concepts underlying developmental trajectories inferred from time-series single-cell data. Pseudodynamics models population distribution shifts across trajectories to quantify selection pressure, population expansion, and developmental potentials. Applying this model to time-resolved single-cell RNA-sequencing of T-cell and pancreatic beta cell maturation, we characterize proliferation and apoptosis rates and identify key developmental checkpoints, data inaccessible to existing approaches.


Assuntos
Diferenciação Celular/genética , Análise de Sequência de RNA/estatística & dados numéricos , Análise de Célula Única/estatística & dados numéricos , Animais , Apoptose/genética , Biotecnologia , Proliferação de Células/genética , Feminino , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Funções Verossimilhança , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Fatores de Tempo
11.
Environ Entomol ; 37(3): 707-18, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18559176

RESUMO

Addition of floral resources to agricultural field margins has been shown to increase abundance of beneficial insects in crop fields, but most plants recommended for this use are non-native annuals. Native perennial plants with different bloom periods can provide floral resources for bees throughout the growing season for use in pollinator conservation projects. To identify the most suitable plants for this use, we examined the relative attractiveness to wild and managed bees of 43 eastern U.S. native perennial plants, grown in a common garden setting. Floral characteristics were evaluated for their ability to predict bee abundance and taxa richness. Of the wild bees collected, the most common species (62%) was Bombus impatiens Cresson. Five other wild bee species were present between 3 and 6% of the total: Lasioglossum admirandum (Sandhouse), Hylaeus affinis (Smith), Agapostemon virescens (F.), Halictus ligatus Say, and Ceratina calcarata/dupla Robertson/Say. The remaining wild bee species were present at <2% of the total. Abundance of honey bees (Apis mellifera L.) was nearly identical to that of B. impatiens. All plant species were visited at least once by wild bees; 9 were highly attractive, and 20 were moderately attractive. Honey bees visited 24 of the 43 plant species at least once. Floral area was the only measured factor accounting for variation in abundance and richness of wild bees but did not explain variation in honey bee abundance. Results of this study can be used to guide selection of flowering plants to provide season-long forage for conservation of wild bees.


Assuntos
Abelhas , Comportamento Animal , Conservação dos Recursos Naturais , Flores , Magnoliopsida , Animais , Michigan , Polinização
12.
Virology ; 521: 99-107, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29902727

RESUMO

Cases of Middle East respiratory syndrome coronavirus (MERS-CoV) continue to occur, making it one of the WHO´s targets for accelerated vaccine development. One vaccine candidate is based on live-attenuated measles virus (MV) vaccine encoding the MERS-CoV spike glycoprotein (MERS-S). MVvac2-MERS-S(H) induces robust humoral and cellular immunity against MERS-S mediating protection. Here, the induction and nature of immunity after vaccination with MVvac2-MERS-S(H) or novel MVvac2-MERS-N were further characterized. We focused on the necessity for vector replication and the nature of induced T cells, since functional CD8+ T cells contribute importantly to clearance of MERS-CoV. While no immunity against MERS-CoV or MV was detected in MV-susceptible mice after immunization with UV-inactivated virus, replication-competent MVvac2-MERS-S(H) triggered robust neutralizing antibody titers also in adult mice. Furthermore, a significant fraction of MERS CoV-specific CD8+ T cells and MV-specific CD4+ T cells simultaneously expressing IFN-γ and TNF-α were induced, revealing that MVvac2-MERS-S(H) induces multifunctional cellular immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Coronavirus/prevenção & controle , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Infecções por Coronavirus/imunologia , Modelos Animais de Doenças , Imunidade Celular , Vírus do Sarampo , Camundongos Endogâmicos BALB C , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Atenuadas/imunologia , Vacinas Virais/genética
13.
BMC Syst Biol ; 10(1): 80, 2016 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-27549154

RESUMO

BACKGROUND: Ordinary differential equation (ODE) models are widely used to describe (bio-)chemical and biological processes. To enhance the predictive power of these models, their unknown parameters are estimated from experimental data. These experimental data are mostly collected in perturbation experiments, in which the processes are pushed out of steady state by applying a stimulus. The information that the initial condition is a steady state of the unperturbed process provides valuable information, as it restricts the dynamics of the process and thereby the parameters. However, implementing steady-state constraints in the optimization often results in convergence problems. RESULTS: In this manuscript, we propose two new methods for solving optimization problems with steady-state constraints. The first method exploits ideas from optimization algorithms on manifolds and introduces a retraction operator, essentially reducing the dimension of the optimization problem. The second method is based on the continuous analogue of the optimization problem. This continuous analogue is an ODE whose equilibrium points are the optima of the constrained optimization problem. This equivalence enables the use of adaptive numerical methods for solving optimization problems with steady-state constraints. Both methods are tailored to the problem structure and exploit the local geometry of the steady-state manifold and its stability properties. A parameterization of the steady-state manifold is not required. The efficiency and reliability of the proposed methods is evaluated using one toy example and two applications. The first application example uses published data while the second uses a novel dataset for Raf/MEK/ERK signaling. The proposed methods demonstrated better convergence properties than state-of-the-art methods employed in systems and computational biology. Furthermore, the average computation time per converged start is significantly lower. In addition to the theoretical results, the analysis of the dataset for Raf/MEK/ERK signaling provides novel biological insights regarding the existence of feedback regulation. CONCLUSION: Many optimization problems considered in systems and computational biology are subject to steady-state constraints. While most optimization methods have convergence problems if these steady-state constraints are highly nonlinear, the methods presented recover the convergence properties of optimizers which can exploit an analytical expression for the parameter-dependent steady state. This renders them an excellent alternative to methods which are currently employed in systems and computational biology.


Assuntos
Biologia Computacional/métodos , Modelos Biológicos , Algoritmos , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Retroalimentação Fisiológica/efeitos dos fármacos , Células HeLa , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Fosforilação/efeitos dos fármacos , Reprodutibilidade dos Testes , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo
14.
Psychiatry Res ; 228(3): 857-65, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-26032462

RESUMO

This study explores whether self-disorders occur and can be assessed reliably in a non-clinical sample, and whether the prevalence of these anomalies depends upon the degree of psychometrically defined schizotypy. Participants with either high (n=30) or low (n=20) schizotypy scores were interviewed using a modified version of the Examination of Anomalous Self-Experience (EASE). The degree to which interviewees experienced self-disorder symptoms was rated by the interviewer and an independent rater. Inter-rater reliability was calculated for each item, domain scores and the total score. For the total, sample most items (=66) showed substantial or perfect agreement (κ>0.61), with a few (=6) showing moderate agreement (κ>0.41). Reliability scores were only slightly lower when just the more homogeneous group of individuals with high Schizotypal Personality Questionnaire (SPQ) scores were examined. As expected, high SPQ scores were associated with a high level of self-disorders. In sum, the results suggest that self-disorders can be measured reliably in non-clinical samples and are particularly frequent in individuals with pronounced schizotypical traits.


Assuntos
Ego , Determinação da Personalidade/estatística & dados numéricos , Transtorno da Personalidade Esquizotípica/diagnóstico , Adulto , Feminino , Humanos , Entrevista Psicológica , Masculino , Programas de Rastreamento/estatística & dados numéricos , Psicometria , Valores de Referência , Reprodutibilidade dos Testes , Inquéritos e Questionários
15.
Behav Brain Res ; 270: 125-30, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24815314

RESUMO

SKAP-HOM is an adapter protein which regulates the cross-talk between immunoreceptors and integrins and is involved in signal transduction. It is present in murine brain structures such as the hippocampus, frontal cortex, and cerebellum. In the present study we investigated types of hippocampus-dependent learning (fear conditioning, social memory, and the Morris Water Maze) and locomotor sensitization to amphetamine in transgenic SKAP-HOM deficient mice (-/-) in comparison with respective controls (+/+). Animals from both groups showed comparable fear conditioning, and the extinction of conditioned fear was accelerated in -/-. In terms of sociability, there were no differences between the animals, but in -/- mice social memory was impaired. There was no difference between the two groups of mice in spatial learning and memory measured in the Morris Water Maze. Wild-type and deficient animals exhibited similar sensitization to amphetamine. In reaction to amphetamine challenge, the response in +/+ was enhanced. It was hypothesized that SKAP-HOM deficiency does not affect hippocampus-dependent learning in general, but that its effects on cognitive tasks seem to be dependent on the nature of the cognitive task, i.e. spatial vs. non-spatial.


Assuntos
Hipocampo , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Aprendizagem em Labirinto , Memória , Animais , Cognição/fisiologia , Condicionamento Clássico/fisiologia , Medo/psicologia , Hipocampo/metabolismo , Locomoção/fisiologia , Masculino , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Camundongos , Camundongos Transgênicos , Testes Psicológicos , Comportamento Social
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