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1.
Int J Lang Commun Disord ; 59(2): 648-664, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37189286

RESUMO

BACKGROUND: Adults with traumatic brain injuries (TBI) frequently experience cognitive, emotional, physical and communication deficits that require long-term rehabilitation and community support. Although access to rehabilitation services is linked to positive outcomes, there can be barriers to accessing community rehabilitation related to system navigation, referral processes, funding, resource allocation and communications required to ensure access. AIMS: This study aimed to identify barriers to accessing insurer funding for rehabilitation and healthcare services, for adults with TBI injured in motor vehicle collisions (MVCs). METHODS: We used a co-design approach to collaborate with persons with lived experience to design a survey of adults who sustained a TBI in an MVC. The survey examined access to insurer funding for rehabilitation services and was disseminated through brain injury networks in Ontario, Canada. RESULTS: Respondents (n = 148) identified multiple barriers to accessing rehabilitation services through insurer funding, including delays of more than 2 years (49%), mandatory duplicative assessments (64%) and invasion of privacy (55%). Speech-language therapy and neuropsychological services were denied most frequently. Negative experiences included insurers' poor understanding of TBI symptoms, denials of services despite medical evidence demonstrating need and unsupportive insurer interactions. Although 70% of respondents reported cognitive-communication difficulties, accommodations were rarely provided. Respondents identified supports that would improve insurer and healthcare communications and rehabilitation access. CONCLUSION & IMPLICATIONS: The insurance claims process had many barriers for adults with TBI, limiting their access to rehabilitation services. Barriers were exacerbated by communication deficits. These findings indicate a role for Speech-language therapists in education, advocacy and communication supports during the insurance process specifically as well as rehabilitation access processes in general. WHAT THIS PAPER ADDS: What is already known on this subject There is extensive documentation of the long-term rehabilitation needs of individuals with traumatic brain injury (TBI) and their challenges in accessing rehabilitation services over the long term. It is also well known that many individuals with TBI have cognitive and communication deficits that affect their interactions in the community, including with healthcare providers, and that SLTs can train communication partners to provide communication supports to individuals with TBI in these communication contexts. What this study adds This study adds important information about barriers to accessing rehabilitation, including barriers to accessing SLT services in the community. We asked individuals with TBI about challenges to accessing auto insurance funding for private community services, and their responses illustrate the broader challenges individuals with TBI face in communicating their deficits, conveying service needs, educating and convincing service administrators and self-advocating. The results also highlight the critical role that communication plays in healthcare access interactions, from completing forms to reviewing reports and funding decisions, to managing telephone calls, writing emails and explaining to assessors. What are the clinical implications of this work? This study shows the lived experience of individuals with TBI in overcoming barriers to accessing community rehabilitation. The results show that best practices in intervention should include evaluating rehabilitation access, which is a critical step in patient-centred care. Evaluation of rehabilitation access includes evaluating referral and navigation, resource allocation and healthcare communications, and ensuring accountability at each step, regardless of model of service delivery or funding source. Finally, these findings show the critical role of speech-language therapists in educating, advocating and supporting communications with funding sources, administrators and other healthcare providers.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Adulto , Humanos , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/reabilitação , Fonoterapia/métodos , Lesões Encefálicas/reabilitação , Comunicação , Cognição
2.
Oncoimmunology ; 12(1): 2217737, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37288324

RESUMO

Immune checkpoint inhibition (ICI) has revolutionized cancer treatment; however, only a subset of patients benefit long term. Therefore, methods for identification of novel checkpoint targets and development of therapeutic interventions against them remain a critical challenge. Analysis of human genetics has the potential to inform more successful drug target discovery. We used genome-wide association studies of the 23andMe genetic and health survey database to identify an immuno-oncology signature in which genetic variants are associated with opposing effects on risk for cancer and immune diseases. This signature identified multiple pathway genes mapping to the immune checkpoint comprising CD200, its receptor CD200R1, and the downstream adapter protein DOK2. We confirmed that CD200R1 is elevated on tumor-infiltrating immune cells isolated from cancer patients compared to the matching peripheral blood mononuclear cells. We developed a humanized, effectorless IgG1 antibody (23ME-00610) that bound human CD200R1 with high affinity (KD <0.1 nM), blocked CD200 binding, and inhibited recruitment of DOK2. 23ME-00610 induced T-cell cytokine production and enhanced T cell-mediated tumor cell killing in vitro. Blockade of the CD200:CD200R1 immune checkpoint inhibited tumor growth and engaged immune activation pathways in an S91 tumor cell model of melanoma in mice.


Assuntos
Leucócitos Mononucleares , Linfócitos T , Humanos , Camundongos , Animais , Estudo de Associação Genômica Ampla , Imunoglobulinas
3.
J Affect Disord ; 274: 602-609, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663993

RESUMO

BACKGROUND: Major Depressive Disorder (MDD) is a common and debilitating mood disorder. Individuals with MDD are often misdiagnosed or diagnosed in an untimely manner, exacerbating existing functional impairments. Ecological momentary assessment (EMA) involves the repeated sampling of an individual's symptoms within their natural environment and has been demonstrated to assist in illness assessment and characterization. Capturing data in this way would set the stage for improved treatment outcomes and serve as a complementary resource in the management and treatment of depressive symptoms. METHODS: Online databases PubMed/MedLine and PsycINFO were searched using PRISMA guidelines and combinations of the following keywords: EMA, depression, smartphone app, diagnosing, symptoms, phone, app, ecological momentary assessment, momentary assessment, data mining, unobtrusive, passive data, GPS, sensor. RESULTS: A total of nineteen original articles were identified using our search parameters and ten articles met the inclusion criteria for full-text review. Among the ten relevant studies, three studies evaluated feasibility, seven evaluated detection, and three evaluated treatment of MDD. LIMITATIONS: Limitations include that the design of all of the studies included in this review are non-randomized. It should be noted that most of the studies included were pilot studies and/or exploratory trials lacking a control group. CONCLUSIONS: Available evidence suggests that the use of passive smartphone-based applications may lead to improved management of depressive symptoms. This review aids the creation of new EMA applications, highlights the potential of EMA usage in clinical settings and drug development, emphasizes the importance for regulation of applications in the mental health field, and provides insight into future directions.


Assuntos
Transtorno Depressivo Maior , Envio de Mensagens de Texto , Depressão , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/terapia , Avaliação Momentânea Ecológica , Humanos , Smartphone
4.
Int J Cancer ; 144(10): 2428-2439, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30411796

RESUMO

It has been encouraged to use large existing data like insurance claims data to investigate the new indications of old drugs. New strategies of research are warranted to identify feasible drugs. We conducted a dual research model with a population-based case-control study using Taiwan's National Health Insurance Research Database and an in vitro study to investigate the association between atypical antipsychotic and Hepatocellular carcinoma (HCC) risk. The study herein consists of two components. The first is a population-based case-control study using existing data from the Taiwan National Health Insurance Research Database. The second component was an in vitro study in which HCC cell lines (Huh7 and Hep G2) were treated with risperidone, quetiapine and clozapine. after treatment of the foregoing antipsychotics, the HCC cell lines were assessed for cell proliferation, invasion and apoptosis. Multivariate conditional logistic regression analysis revealed that antipsychotic use was independently and inversely associated with HCC risk (adjusted odds-ratio [aOR]:0.85, 95% CI: 0.81-0.89). The protective effect was dose-dependent: compared to the low cumulative defined daily dose (cDDD) group (0-29 cDDD), the 30-89 cDDD and ≥90 cDDD groups were associated with significantly reduced risk for HCC (aOR: 0.56, 95% CI: 0.41-0.76; aOR: 0.37, 95% CI: 0.27-0.50, respectively). In vitro study results indicated that risperidone, quetiapine and clozapine significantly inhibited cell proliferation, invasion and induced apoptosis in human HCC cell lines. Our results herein suggested that antipsychotic use might reduce the risk of HCC and may provide evidence for new uses of old drugs.


Assuntos
Antipsicóticos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Células Hep G2 , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Taiwan , Adulto Jovem
5.
Ann Clin Psychiatry ; 31(1): 17-26, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30372511

RESUMO

BACKGROUND: The aim of this study was to examine the role of perceived sleep quality in predicting subjective as well as objective cognitive function in adults with major depressive disorder (MDD). METHODS: Adults with recurrent MDD (n = 100) experiencing a major depressive episode of at least moderate severity and age-, sex-, and education-matched healthy controls (HC) (n = 100) were recruited to participate in a clinical trial validating the THINC-integrated tool (THINC-it; NCT02508493) for cognitive function. The THINC-it includes subjective and objective measures of cognitive function. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). RESULTS: Compared with HC, individuals with MDD reported significantly poorer sleep quality, as assessed by domain and global PSQI scores (all P values <.05). Both perceived sleep quality (P < .001) and depression severity (P = .002) were found to independently predict impairments in subjective cognitive performance. Only perceived sleep quality predicted objective cognitive impairments (P = .017). Exploratory mediation analysis revealed depression severity to be a partial mediator of the relationship between perceived sleep quality and subjective cognitive performance (95% confidence interval [CI]: -0.56, -0.33). CONCLUSIONS: The results indicate that the subjective and objective cognitive impairments are differentially related to perceived sleep quality and depression severity and emphasize the importance of treating sleep disturbances in MDD.


Assuntos
Cognição/fisiologia , Transtorno Depressivo Maior/psicologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Recidiva , Inquéritos e Questionários
6.
Ann Clin Psychiatry ; 30(1): 25-31, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29373615

RESUMO

BACKGROUND: Individuals with binge eating disorder (BED) are differentially affected by attention-deficit/hyperactivity disorder (ADHD), obesity, and substance use disorder. We have investigated to what extent cognitive deficits are relevant to binge eating behavior (BEB). METHODS: Data from the International Mood Disorders Collaborative Project were retrospectively and cross-sectionally analyzed to compare individuals with and without BEB on measures of anhedonia and general cognitive functions (n = 566). BEB was assessed using items from the Mini International Neuropsychiatric Interview Plus 5.0.0 for DSM-IV-TR that correspond with DSM-5-defined diagnostic criteria for BED. Individuals currently prescribed benzodiazepines were excluded from analyses. RESULTS: Individuals with BEB were more likely to exhibit anhedonia (P = .044) and general cognitive (P = .005) symptoms, when compared to those without BEB. We also observed that individuals with BEB were more likely to have specific psychiatric (eg, ADHD) and medical (eg, obesity) disorders (P < .05). CONCLUSIONS: Our results suggest that a central disturbance in cognitive processes may be mechanistically relevant to the cause and treatment of BEB in adults.


Assuntos
Transtorno da Compulsão Alimentar/psicologia , Transtornos Cognitivos/psicologia , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Adulto , Anedonia/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade , Estudos Retrospectivos
7.
Ann Clin Psychiatry ; 30(1): 38-50, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29373617

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with deficits across multiple cognitive domains; however, the determinants of cognitive impairment in T2DM are not well characterized. We aimed to evaluate body mass index (BMI), glycemic control, and T2DM duration as moderators of cognitive dysfunction in T2DM. METHODS: We conducted a meta-analytic review of the literature reporting data on BMI, hemoglobin A1c (HbA1c), T2DM duration, and validated measures of processing speed (ie, Digit Symbol Substitution Test, Trail Making Test [TMT]-A), verbal learning and memory (ie, Rey Auditory Verbal Learning Test), and working memory/executive function (ie, TMT-B) among individuals with vs without T2DM. RESULTS: Individuals with T2DM demonstrated deficits across multiple cognitive domains (k = 40; n = 4,252 T2DM; n = 22,322 non-T2DM; effect sizes 0.21 to 0.35). Illness duration and BMI did not significantly moderate measures of cognition; however, higher HbA1c levels were significantly associated with deficits in measures of processing speed (R2 values 0.41 to 0.73, P < .01) and working memory/executive function (R2 = 0.62, P < .001). CONCLUSIONS: Adults with T2DM exhibited significant deficits across multiple domains of cognitive function. Additionally, we identified an association between poorer glycemic control and cognitive dysfunction. A clinical translation of our findings relates to the reduction in morbidity by improving glycemic control.


Assuntos
Disfunção Cognitiva/psicologia , Diabetes Mellitus Tipo 2/psicologia , Hemoglobinas Glicadas/análise , Complicações do Diabetes , Humanos , Testes Neuropsicológicos/estatística & dados numéricos
8.
Scand J Pain ; 15: 62-67, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28850348

RESUMO

OBJECTIVES: To examine the role of pain on cognitive function in adults with major depressive disorder (MDD). METHODS: Adults (18-65) with a Diagnostic and Statistical Manual - Fifth Edition (DSM-5)-defined diagnosis of MDD experiencing a current major depressive episode (MDE) were enrolled (nMDD=100). All subjects with MDD were matched in age, sex, and years of education to healthy controls (HC) (nHC=100) for comparison. Cognitive function was assessed using the recently validated THINC-integrated tool (THINC-it), which comprises variants of the choice reaction time (i.e., THINC-it: Spotter), One-Back (i.e., THINC-it: Symbol Check), Digit Symbol Substitution Test (i.e., THINC-it: Codebreaker), Trail Making Test - Part B (i.e., THINC-it: Trails), as well as the Perceived Deficits Questionnaire for Depression - 5-item (i.e., THINC-it: PDQ-5-D). A global index of objective cognitive function was computed using objective measures from the THINC-it, while self-rated cognitive deficits were measured using the PDQ-5-D. Pain was measured using a Visual Analogue Scale (VAS). Regression analyses evaluated the role of pain in predicting objective and subjective cognitive function. RESULTS: A significant between-group differences on the VAS was observed (p<0.001), with individuals with MDD reporting higher pain severity as evidenced by higher scores on the VAS than HC. Significant interaction effects were observed between self -rated cognitive deficits and pain ratings (p<0.001) on objective cognitive performance (after adjusting for MADRS total score), suggesting that pain moderates the association between self-rated and objective cognitive function. CONCLUSIONS: Results indicated that pain is associated with increased self-rated and objective cognitive deficits in adults with MDD. IMPLICATIONS: The study herein provides preliminary evidence demonstrating that adults with MDD reporting pain symptomatology and poorer subjective cognitive function is predictive of poorer objective cognitive performance. THINC-it is capable of detecting cognitive dysfunction amongst adults with MDD and pain.


Assuntos
Disfunção Cognitiva/etiologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/psicologia , Dor/complicações , Dor/psicologia , Adolescente , Adulto , Idoso , Cognição , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Adulto Jovem
9.
J Clin Psychopharmacol ; 37(4): 412-418, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28590365

RESUMO

BACKGROUND: Psychostimulants are frequently prescribed off-label for adults with major depressive disorder or bipolar disorder. The frequent and increasing usage of stimulants in mood disorders warrants a careful appraisal of the efficacy of this class of agents. Herein, we aim to estimate the efficacy of psychostimulants in adults with unipolar or bipolar depression. METHODS: The PubMed/Medline database was searched from inception to January 16, 2016 for randomized, placebo-controlled clinical trials investigating the antidepressant efficacy of psychostimulants in the treatment of adults with unipolar or bipolar depression. RESULTS: Psychostimulants were associated with statistically significant improvement in depressive symptoms in major depressive disorder (odds ratio [OR], 1.41; 95% confidence interval [CI], 1.13-1.78; P = 0.003) and bipolar disorder (OR, 1.42; 95% CI, 1.13-1.78; P = 0.003). Efficacy outcomes differed across the psychostimulants evaluated as a function of response rates: ar/modafinil (OR, 1.47; 95% CI, 1.20-1.81; P = 0.0002); dextroamphetamine (OR, 7.11; 95% CI, 1.09-46.44; P = 0.04); lisdexamfetamine dimesylate (OR, 1.21; 95% CI, 0.94-1.56; P = ns); methylphenidate (OR, 1.49; 95% CI, 0.88-2.54; P = ns). Efficacy outcomes also differed between agents used as adjunctive therapy (OR, 1.39; 95% CI, 1.19-1.64) or monotherapy (OR, 2.25; 95% CI, 0.67-7.52). CONCLUSIONS: Psychostimulants are insufficiently studied as adjunctive or monotherapy in adults with mood disorders. Most published studies have significant methodological limitations (eg, heterogeneous samples, dependent measures, type/dose of agent). In addition to improvements in methodological factors, a testable hypothesis is that psychostimulants may be more appropriately tested in select domains of psychopathology (eg, cognitive emotional processing), rather than as "broad-spectrum" antidepressants.


Assuntos
Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/tratamento farmacológico , Psicotrópicos/uso terapêutico , Compostos Benzidrílicos/uso terapêutico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Transtorno Depressivo Maior/psicologia , Dextroanfetamina/uso terapêutico , Humanos , Metilfenidato/uso terapêutico , Modafinila , Resultado do Tratamento
10.
Adv Ther ; 34(1): 78-90, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27913990

RESUMO

Convergent evidence indicates that abnormalities in the innate immune system may be pertinent to the pathogenesis, phenomenology, and possible treatment of several mental disorders. In keeping with this view, the targeting of interleukin-6 with the human monoclonal antibody sirukumab may represent a possible treatment and disease modification approach, for adults with brain-based disorders (e.g., major depressive disorder). A PubMed/Medline database search was performed using the following search terms: sirukumab; anti-IL-6; IL-6; major depressive disorder; inflammation. A systematic review was conducted of both preclinical and clinical trials reporting on the pharmacology of sirukumab or investigating the efficacy of targeting IL-6 signaling. Overall, sirukumab has been reported to be a safe and well-tolerated agent, capable of modulating the immune response in healthy populations as well as in subjects with inflammatory disorders (e.g., rheumatoid arthritis). Sirukumab's effects on cytokine networks as part of the innate immune system provide a coherent rationale for possible application in neuropsychiatric disorders with possible benefits across several domains of the biobehavioral Research Domain Criteria matrix (e.g., general cognitive processes, positive valence systems). Amongst individuals with complex brain-based disorders (e.g., mood disorders), the dimensions/domains most likely to benefit with sirukumab are negative valence disturbances (e.g., anxiety, depression, rumination), positive valence disturbances (e.g., anhedonia) as well as general cognitive processes. We suggest that sirukumab represents a prototype and possibly a proof-of-concept that agents that engage IL-6 targets have salutary effects in psychiatry.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Inflamação/tratamento farmacológico , Interleucina-6/antagonistas & inibidores , Adulto , Anticorpos Monoclonais Humanizados , Transtorno Depressivo Maior/imunologia , Humanos , Inflamação/imunologia , Masculino , Transtornos do Humor/tratamento farmacológico , Transtornos do Humor/imunologia
11.
Proc Natl Acad Sci U S A ; 111(44): 15741-5, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25331893

RESUMO

There are many transmembrane receptor-like proteins whose ligands have not been identified. A strategy for finding ligands when little is known about their tissue source is to screen each extracellular protein individually expressed in an array format by using a sensitive functional readout. Taking this approach, we have screened a large collection (3,191 proteins) of extracellular proteins for their ability to activate signaling of an orphan receptor, leukocyte tyrosine kinase (LTK). Only two related secreted factors, FAM150A and FAM150B (family with sequence similarity 150 member A and member B), stimulated LTK phosphorylation. FAM150A binds LTK extracellular domain with high affinity (K(D) = 28 pM). FAM150A stimulates LTK phosphorylation in a ligand-dependent manner. This strategy provides an efficient approach for identifying functional ligands for other orphan receptors.


Assuntos
Citocinas/metabolismo , Proteoma/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais/fisiologia , Citocinas/genética , Feminino , Células HEK293 , Humanos , Masculino , Fosforilação/fisiologia , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína , Proteoma/genética , Proteômica , Receptores Proteína Tirosina Quinases/genética
12.
J Craniofac Surg ; 24(2): 354-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23524692

RESUMO

Calcium phosphate ceramics such as hydroxyapatite (HA) and biphasic calcium phosphates are used clinically to repair bone defects. These calcium phosphate ceramics can differ by composition, structure, and rate of degradation. This study compared 3 calcium phosphate ceramics, 2 of which have similar structure but different composition: 100% HA (algae derived) and HA/ß-tricalcium phosphate (ß-TCP) 20/80 (algae derived), and 2 with different structure but similar composition: HA/ß-TCP 20/80 (algae derived) and HA/ß-TCP 15/85 (synthetic). Calcium phosphate ceramics can be difficult to handle and contour during the surgeries. To improve handling, Poloxamer 407 (P407) was added to the 3 ceramics, and its effect on bone healing was also assessed. Bilateral calvarial defects created in the parietal bones of New Zealand white rabbits were left unfilled or were filled with autograft or one of the ceramics, with and without P407. Six weeks after operation, healing was evaluated qualitatively by histology and quantitatively by micro-computed tomography analysis and histomorphometry. All 3 calcium phosphate ceramics demonstrated osteoconductivity and performed similarly in supporting new bone formation, suggesting that the differences in their composition, structure, or degradation did not significantly affect their ability to promote bone healing in this application. Incorporating P407 did not impede osteoconductivity as HA and biphasic calcium phosphate combined with P407 performed similarly as when used alone for craniofacial defect repair.


Assuntos
Fosfatos de Cálcio/química , Osteogênese/efeitos dos fármacos , Poloxâmero/química , Rodófitas/química , Crânio/cirurgia , Cicatrização/efeitos dos fármacos , Animais , Masculino , Coelhos , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
13.
Growth Factors ; 30(4): 267-75, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22583106

RESUMO

Proteolytic cleavage of precursor bone morphogenetic protein (proBMP) is an important step in generating the active mature BMP. ProBMP-2 contains two proprotein convertase (PC) recognition sites (S1 and S2) and is postulated to be cleaved by PCs at those sites. Cell lines expressing proBMP-2, with a silenced S1 site (mS1) that inhibited PC cleavage, secreted the 20-kDa form BMP-2, while cells expressing wild type (wt) BMP-2 secreted 18- and 20-kDa mature BMP-2 N-terminal isoforms. The mS1 cells secreted 15-fold more mature BMP-2 than the wt, despite their similar mRNA levels. Mutant-secreted BMP-2 demonstrated biological activity in vitro; however, its activity was reduced compared with wt. These data demonstrate that proBMP-2 can be cleaved at an alternative cleavage site without prior S1 site cleavage in cell lines overexpressing BMP-2 and more importantly suggest that the presence of the 2-kDa linker peptide can affect activity and secretion of the mature protein.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Regulação da Expressão Gênica , Mutação , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 2/genética , Células CHO , Cricetinae , Ensaio de Imunoadsorção Enzimática/métodos , Células HEK293 , Humanos , Camundongos , Dados de Sequência Molecular , Peptídeos/química , Reação em Cadeia da Polimerase/métodos , Isoformas de Proteínas , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos
14.
Biotechnol Lett ; 34(2): 221-30, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22038549

RESUMO

To improve recombinant human bone morphogenetic protein-2 (rhBMP-2) yield, cell lines stably expressing hBMP2 were cultured in the presence of polyarginine peptide IND-1 and showed up to 6-fold increase in the yield of mature BMP-2. Repeated addition of IND-1 to cell cultures consistently improved BMP-2 yields over 53 days without affecting cell growth and viability. Investigation of its mechanism of action showed that IND-1 inhibited pro-protein convertase (PC) activity when incubated with cell lysates. However, when intact cells were cultured with IND-1, no change in cellular PC activity was observed. Furthermore, knockdown of furin (a prototypical member of the PCs) in cells did not affect their BMP-2 yields, suggesting furin/PC inhibition is unlikely the mechanism by which IND-1 enhances BMP-2 yields. IND-1 as a medium additive thus enhances BMP-2 production in mammalian cell expression systems.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Peptídeos/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Linhagem Celular , Cricetinae , Meios de Cultura/química , Humanos , Proteínas Recombinantes/metabolismo
16.
Science ; 320(5877): 807-11, 2008 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-18467591

RESUMO

To understand the system of secreted proteins and receptors involved in cell-cell signaling, we produced a comprehensive set of recombinant secreted proteins and the extracellular domains of transmembrane proteins, which constitute most of the protein components of the extracellular space. Each protein was tested in a suite of assays that measured metabolic, growth, or transcriptional responses in diverse cell types. The pattern of responses across assays was analyzed for the degree of functional selectivity of each protein. One of the highly selective proteins was a previously undescribed ligand, designated interleukin-34 (IL-34), which stimulates monocyte viability but does not affect responses in a wide spectrum of other assays. In a separate functional screen, we used a collection of extracellular domains of transmembrane proteins to discover the receptor for IL-34, which was a known cytokine receptor, colony-stimulating factor 1 (also called macrophage colony-stimulating factor) receptor. This systematic approach is thus useful for discovering new ligands and receptors and assessing the functional selectivity of extracellular regulatory proteins.


Assuntos
Espaço Extracelular/química , Interleucinas/isolamento & purificação , Receptores de Interleucina/isolamento & purificação , Animais , Clonagem Molecular , DNA Complementar , Humanos , Interleucinas/metabolismo , Interleucinas/fisiologia , Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/fisiologia , Estrutura Terciária de Proteína , Proteoma , Receptores de Interleucina/fisiologia
17.
J Craniofac Surg ; 18(6): 1264-75, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17993867

RESUMO

Calcium phosphates like hydroxyapatite (HA), beta-tricalcium phosphate (beta-TCP), and their mixtures (biphasic calcium phosphates; BCP) are used clinically to repair bone defects. These materials can be difficult to handle and have no inherent biological activity. Handling properties of other bone substitute materials have been improved by combining them with an inert carrier such as Pluronic F-127 (Pluronic, BASF, Mt. Olive, NJ), while the addition of bone morphogenetic proteins (BMP) with such implants has also been shown to enhance bone repair. This study assessed the impact of adding Pluronic and BMPs to an HA (C-Graft) or a BCP (80/20 HA/beta-TCP ratio; Algisorb) implant's ability of promote bony repair in the rabbit calvarial defect model.Twenty-five New Zealand white rabbits were divided into 5 groups of 5 animals each. Bilateral calvarial defects were made in the parietal bones of each animal. HA or BCP alone or combined with Pluronic and/or BMP were implanted into the defect sites. Animals were euthanized at 6 weeks, postoperatively. Bone regeneration was evaluated quantitatively by histomorphometry. The amount of bone regeneration, which occurred in defects containing HA and BCP, was similar over the time period studied. Incorporating Pluronic increased handling and moldability without compromising osteoconductivity of either calcium phosphate. The addition of BMP significantly increased the amount of new bone formed with all calcium phosphates studied (P < 0.05). These results suggest that Pluronic can be added to calcium phosphates to enhance handling and moldability without any negative effects on their biocompatibility and that healing can be enhanced with the incorporation of BMPs.


Assuntos
Implantes Absorvíveis , Alginatos/farmacologia , Proteínas Morfogenéticas Ósseas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos , Portadores de Fármacos , Glucuronatos/farmacologia , Poloxâmero , Animais , Fosfatos de Cálcio , Combinação de Medicamentos , Durapatita , Masculino , Osso Parietal/cirurgia , Coelhos , Procedimentos de Cirurgia Plástica
18.
Assay Drug Dev Technol ; 4(2): 175-83, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16712421

RESUMO

SH2 domain-containing inositol 5-phosphatase 2 (SHIP2) is a potential drug target for the treatment of type 2 diabetes. This enzyme serves as a negative regulator of insulin-mediated signal transduction by catalyzing the dephosphorylation of the second messenger lipid molecule phosphatidylinositol 3,4,5-triphosphate. Traditionally, assays for phosphoinositide phosphatases such as SHIP2 have relied on radiolabeled phosphatidylinositol-containing lipid membranes and chromatographic separation of labeled phospholipid substrate from product by thin-layer chromatography. We have expressed and purified catalytically active phosphatase domain constructs of SHIP2 from Escherichia coli and developed a sensitive and antibody- or binding protein-independent assay for SHIP2 amenable to high-throughput screening of phosphoinositide phosphatases or phosphoinositide kinases. This microfluidic assay, with Z' values approximately 0.8, is based upon the difference in mobility within an electric field between a fluorophore-labeled phosphatidylinositol 3,4,5-triphosphate substrate and the corresponding 3,4-bisphosphate product. High-throughput screening of a 91,060-member compound library in 384-well format resulted in the identification of SHIP2 inhibitors.


Assuntos
Técnicas Analíticas Microfluídicas , Monoéster Fosfórico Hidrolases/análise , Cromatografia em Camada Fina , Dimetil Sulfóxido/química , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Regulação Enzimológica da Expressão Gênica , PTEN Fosfo-Hidrolase/análise , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/análise , Fosfatidilinositol 3-Quinases/genética , Fosfatos de Fosfatidilinositol/análise , Fosfatos de Fosfatidilinositol/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/genética , Proteínas Recombinantes/análise , Transdução de Sinais , Transfecção
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