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1.
BMC Psychiatry ; 23(1): 597, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592231

RESUMO

BACKGROUND: Digital self-management tools blended with clinical triage and peer support have the potential to improve access to early warning signs (EWS) based relapse prevention in schizophrenia care. However, the implementation of digital interventions in psychosis can be poor. Traditionally, research focused on understanding how people implement interventions has focused on the perspectives of mental health staff. Digital interventions are becoming more commonly used by patients within the context of daily life, which means there is a need to understand implementation from the perspectives of patients and carers. METHODS: Semi-structured one-on-one interviews with 16 patients who had access to the EMPOWER digital self-management intervention during their participation in a feasibility trial, six mental health staff members who supported the patients and were enrolled in the trial, and one carer participant. Interviews focused on understanding implementation, including barriers and facilitators. Data were coded using thematic analysis. RESULTS: The intervention was well implemented, and EMPOWER was typically perceived positively by patients, mental health staff and the carer we spoke to. However, some patients reported negative views and reported ideas for intervention improvement. Patients reported valuing that the app afforded them access to things like information or increased social contact from peer support workers that went above and beyond that offered in routine care. Patients seemed motivated to continue implementing EMPOWER in daily life when they perceived it was creating positive change to their wellbeing, but seemed less motivated if this did not occur. Mental health staff and carer views suggest they developed increased confidence patients could self-manage and valued using the fact that people they support were using the EMPOWER intervention to open up conversations about self-management and wellbeing. CONCLUSIONS: The findings from this study suggest peer worker supported digital self-management like EMPOWER has the potential to be implemented. Further evaluations of these interventions are warranted, and conducting qualitative research on the feasibility gives insight into implementation barriers and facilitators, improving the likelihood of interventions being usable. In particular, the views of patients who demonstrated low usage levels would be valuable.


Assuntos
Comunicação , Transtornos Psicóticos , Humanos , Saúde Mental , Grupo Associado , Probabilidade , Transtornos Psicóticos/terapia
2.
Cardiol Young ; 33(11): 2350-2356, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36876641

RESUMO

OBJECTIVE: We aimed to identify factors independently associated with the need for inotropic support for low cardiac output or haemodynamic instability after pulmonary artery banding surgery for CHD. METHODS: We performed a retrospective chart review of all neonates and infants who underwent pulmonary banding between January 2016 and June 2019 at our institution. Bivariate and multivariable analyses were performed to identify factors independently associated with the use of post-operative inotropic support, defined as the initiation of inotropic infusion(s) for depressed myocardial function, hypotension, or compromised perfusion within 24 hours of pulmonary artery banding. RESULTS: We reviewed 61 patients. Median age at surgery was 10 days (25%,75%:7,30). Cardiac anatomy was biventricular in 38 patients (62%), hypoplastic right ventricle in 14 patients (23%), and hypoplastic left ventricle in 9 patients (15%). Inotropic support was implemented in 30 patients (49%). Baseline characteristics of patients who received inotropic support, including ventricular anatomy and pre-operative ventricular function, were not statistically different from the rest of the cohort. Patients who received inotropic support, however, were exposed to larger cumulative doses of ketamine intraoperatively - median 4.0 mg/kg (25%,75%:2.8,5.9) versus 1.8 mg/kg (25%,75%:0.9,4.5), p < 0.001. In a multivariable model, cumulative ketamine dose greater than 2.5mg/kg was associated with post-operative inotropic support (odds ratio 5.5; 95% confidence interval: 1.7,17.8), independent of total surgery time. CONCLUSIONS: Inotropic support was administered in approximately half of patients who underwent pulmonary artery banding and more commonly occurred in patients who received higher cumulative doses of ketamine intraoperatively, independent of the duration of surgery.


Assuntos
Ketamina , Artéria Pulmonar , Lactente , Recém-Nascido , Humanos , Artéria Pulmonar/cirurgia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
3.
Eur Spine J ; 30(9): 2613-2621, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34050807

RESUMO

PURPOSE: To examine whether unilateral multifidus damage could promote degeneration at the L5-6 facet joint (FJ) and compensatory changes in lumbo-pelvic muscles in rats. METHODS: 12 facet clamp, 12 facet sham and 7 control rats were studied. Facet clamp and sham animals had the left L5-6 FJ exposed, and the clamp group had a mild compressive clamp applied using hemostatic forceps to model post-traumatic arthritis. Both groups then had the left multifidus detached from the L1-L6 spinous processes. Animals were euthanized 28 days post-surgery. Muscle mass and fascicle length were evaluated bilaterally for the paraspinal muscles, gluteal muscles and biceps femoris. Intra-muscular collagen of the paraspinal muscles was measured histologically. FJ transverse plane angles were measured from micro-computed tomography scans. L5-6 FJ degeneration was evaluated through the 24-point OARSI scale. RESULTS: Differences, compared to control, were observed in the detached multifidus from both facet clamp and sham groups; namely decreased mass and fascicle length and increased collagen content. However, no between group differences were found for any other muscle. Further, mild FJ degeneration was more prevalent in the groups that had experienced multifidus injury but was not exacerbated by the mild compressive clamping of the FJ. CONCLUSION: Unilateral multifidus injury with or without FJ compressive clamping does not have a clear impact on the characteristics of surrounding spinal musculature within 28 days post-surgery in rats. Mild FJ degeneration was present in some animals from all three groups, and the impact of multifidus injury on this degeneration is inconclusive.


Assuntos
Espondilose , Articulação Zigapofisária , Animais , Músculos Paraespinais/diagnóstico por imagem , Ratos , Microtomografia por Raio-X , Articulação Zigapofisária/diagnóstico por imagem
4.
Vet Surg ; 49(1): 106-113, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31664725

RESUMO

OBJECTIVE: To determine the influence of prophylactic administration of oral antimicrobial medications after tibial plateau leveling osteotomy (TPLO) on surgical site infections (SSI) and antimicrobial-resistant infections. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Dogs treated with unilateral TPLO (n = 308) between January 2013 and December 2015. METHODS: Medical records were reviewed for signalment, surgically treated limb, duration of surgery and anesthesia, postoperative administration of antimicrobial medications, antibiotic agent, surgeon, and development of SSI. Statistical analyses included descriptive statistics, simple linear regression, analysis of variance, Fisher's protected least significant difference, and χ2 testing. RESULTS: Data were collected from records of 31 dogs that did not receive antimicrobial medications and 277 dogs that did receive oral antimicrobial medications for 14 days after TPLO. Superficial incisional SSI was detected in two of 31 dogs that did not receive antimicrobial medications and in 48 of 277 dogs that did receive antimicrobial medications (P = .1194). Deep incisional SSI occurred in two of 31 dogs that did not receive antimicrobial medications and in 27 of 277 dogs that did receive antimicrobial medications (P = .5513). Antibiotic-resistant deep incisional SSI occurred in two of 31 dogs that did not receive antimicrobial medications and in 18 of 277 dogs that did receive antimicrobial medications (P = .9920). Body weight correlated with deep incisional SSI and resistant infections. Prolonged duration of surgery and anesthesia were associated with superficial incisional SSI, deep incisional SSI, and antibiotic resistance. Surgeons influenced deep incisional SSI. CONCLUSION: Previously reported predisposing factors for infection were confirmed, but postoperative administration of antimicrobial medications was not protective against SSI nor did it predispose to antibiotic resistance in our clinical setting. CLINICAL SIGNIFICANCE: This study does not provide evidence to support administration of prophylactic oral antimicrobial medications after unilateral TPLO.


Assuntos
Anti-Infecciosos/uso terapêutico , Cães/lesões , Osteotomia/veterinária , Infecção da Ferida Cirúrgica/veterinária , Tíbia/cirurgia , Administração Oral , Animais , Anti-Infecciosos/administração & dosagem , Cães/cirurgia , Feminino , Masculino , Período Pós-Operatório , Registros/veterinária , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/prevenção & controle , Resultado do Tratamento
5.
J Med Internet Res ; 21(10): e14366, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31651400

RESUMO

BACKGROUND: Relapse is a common experience for people diagnosed with psychosis, which is associated with increased service costs and profound personal and familial distress. EMPOWER (Early signs Monitoring to Prevent relapse in psychosis and prOmote Well-being, Engagement, and Recovery) is a peer worker-supported digital intervention that aims to enable service users to self-monitor their mental health with the aim of encouraging self-management and the shared use of personal data to promote relapse prevention. Digital interventions have not been widely used in relapse prevention and, therefore, little is currently known about their likely implementation-both within trials and beyond. OBJECTIVE: Seeking the perspectives of all relevant stakeholder groups is recommended in developing theories about implementation because this can reveal important group differences in understandings and assumptions about whether and for whom the intervention is expected to work. However, the majority of intervention implementation research has been retrospective. This study aimed to discover and theoretically frame implementation expectations in advance of testing and synthesize these data into a framework. METHODS: To develop a hypothetical implementation framework, 149 mental health professionals, carers, and people diagnosed with psychosis participated in 25 focus groups in both Australia and the United Kingdom. An interview schedule informed by the normalization process theory was used to explore stakeholders' expectations about the implementation of the EMPOWER intervention. Data were analyzed using thematic analysis and then theoretically framed using the Medical Research Council guidelines for understanding the implementation of complex interventions. RESULTS: All groups expected that EMPOWER could be successfully implemented if the intervention generated data that were meaningful to mental health staff, carers, and service users within their unique roles. However, there were key differences between staff, carers, and service users about what facilitators and barriers that stakeholders believe exist for intervention implementation in both the cluster randomized controlled trial stage and beyond. For example, service user expectations mostly clustered around subjective user experiences, whereas staff and carers spoke more about the impact upon staff interactions with service users. CONCLUSIONS: A hypothetical implementation framework synthesized from stakeholder implementation expectations provides an opportunity to compare actual implementation data gathered during an ongoing clinical trial, giving valuable insights into the accuracy of these stakeholders' previous expectations. This is among the first studies to assess and record implementation expectations for a newly developed digital intervention for psychosis in advance of testing in a clinical trial. TRIAL REGISTRATION: ISRCTN Registry ISRCTN99559262; http://www.isrctn.com/ISRCTN99559262.


Assuntos
Aplicativos Móveis/normas , Transtornos Psicóticos/diagnóstico , Humanos , Transtornos Psicóticos/psicologia , Pesquisa Qualitativa , Recidiva , Estudos Retrospectivos , Autogestão
6.
J Proteome Res ; 15(3): 815-25, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26784366

RESUMO

The risk of developing post-traumatic osteoarthritis (PTOA) following joint injury is high. Furthering our understanding of the molecular mechanisms underlying PTOA and/or identifying novel biomarkers for early detection may help to improve treatment outcomes. Increased expression of integrin α1ß1 and inhibition of epidermal growth factor receptor (EGFR) signaling protect the knee from spontaneous OA; however, the impact of the integrin α1ß1/EGFR axis on PTOA is currently unknown. We sought to determine metabolic changes in serum samples collected from wild-type and integrin α1-null mice that underwent surgery to destabilize the medial meniscus and were treated with the EGFR inhibitor erlotinib. Following (1)H nuclear magnetic resonance spectroscopy, we generated multivariate statistical models that distinguished between the metabolic profiles of erlotinib- versus vehicle-treated mice and the integrin α1-null versus wild-type mouse genotype. Our results show the sex-dependent effects of erlotinib treatment and highlight glutamine as a metabolite that counteracts this treatment. Furthermore, we identified a set of metabolites associated with increased reactive oxygen species production, susceptibility to OA, and regulation of TRP channels in α1-null mice. Our study indicates that systemic pharmacological and genetic factors have a greater effect on serum metabolic profiles than site-specific factors such as surgery.


Assuntos
Cloridrato de Erlotinib/farmacologia , Integrina alfa1/genética , Metaboloma , Osteoartrite do Joelho/sangue , Animais , Receptores ErbB , Cloridrato de Erlotinib/uso terapêutico , Feminino , Masculino , Meniscos Tibiais/cirurgia , Metaboloma/efeitos dos fármacos , Metaboloma/genética , Camundongos , Camundongos Knockout , Osteoartrite do Joelho/tratamento farmacológico , Espécies Reativas de Oxigênio , Canais de Potencial de Receptor Transitório
7.
Nanotechnology ; 27(7): 075103, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26788907

RESUMO

Although metal-metal oxide nanoparticles have attracted considerable interest as catalysts, they have attracted little interest in nanomedicine. This is likely due to the fact that metal oxide semiconductors generally require biologically harmful ultraviolet excitation. In contrast, this study focuses upon WO3/Pt nanoparticles, which can be excited by visible light. To optimize the nanoparticles' catalytic performance, platinization was performed at alkaline pH. These nanoparticles destroyed organic dyes, consumed dissolved oxygen and produced hydroxyl radicals. 4T1 breast cancer cells internalized WO3/Pt nanoparticles within the membrane-bound endo-lysosomal compartment as shown by electron and fluorescence microscopy. During visible light exposure, but not in darkness, WO3/Pt nanoparticles manufacture reactive oxygen species, promote lipid peroxidation, and trigger lysosomal membrane disruption. As cells of the immune system degrade organic molecules, produce reactive oxygen species, and activate the lipid peroxidation pathway within target cells, these nanoparticles mimic the chemical attributes of immune effector cells. These biomimetic nanoparticles should become useful in managing certain cancers, especially ocular cancer.


Assuntos
Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Nanopartículas/química , Óxidos/farmacologia , Platina/farmacologia , Tungstênio/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Luz , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Nanopartículas/ultraestrutura , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Óxidos/química , Platina/química , Espécies Reativas de Oxigênio/metabolismo , Tungstênio/química
8.
Nanotechnology ; 27(6): 065101, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26683660

RESUMO

To provide a means of delivering an artificial immune effector cell-like attack on tumor cells, we report the tumoricidal ability of inorganic WO3/Pt nanoparticles that mimic a leukocyte's functional abilities. These nanoparticles route electrons from organic structures and electron carriers to form hydroxyl radicals within tumor cells. During visible light exposure, WO3/Pt nanoparticles manufacture hydroxyl radicals, degrade organic compounds, use NADPH, trigger lipid peroxidation, promote lysosomal membrane disruption, promote the loss of reduced glutathione, and activate apoptosis. In a model of advanced breast cancer metastasis to the eye's anterior chamber, we show that WO3/Pt nanoparticles prolong the survival of 4T1 tumor-bearing Balb/c mice. This new generation of inorganic photosensitizers do not photobleach, and therefore should provide an important therapeutic advance in photodynamic therapy. As biomimetic nanoparticles destroy targeted cells, they may be useful in treating ocular and other forms of cancer.


Assuntos
NADPH Oxidases/metabolismo , Nanopartículas/administração & dosagem , Óxidos/farmacologia , Platina/farmacologia , Tungstênio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Biomimética/métodos , Catálise/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Radical Hidroxila/química , Luz , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oxirredução/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia
9.
Biochem Biophys Res Commun ; 445(1): 184-90, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24495803

RESUMO

BACKGROUND/PURPOSE: The goal of this study was to determine the role of the collagen binding receptor integrin α1ß1 in regulating osmotically induced [Ca(2+)]i transients in chondrocytes. METHOD: The [Ca(2+)]i transient response of chondrocytes to osmotic stress was measured using real-time confocal microscopy. Chondrocytes from wildtype and integrin α1-null mice were imaged ex vivo (in the cartilage of intact murine femora) and in vitro (isolated from the matrix, attached to glass coverslips). Immunocytochemistry was performed to detect the presence of the osmosensor, transient receptor potential vanilloid-4 (TRPV4), and the agonist GSK1016790A (GSK101) was used to test for its functionality on chondrocytes from wildtype and integrin α1-null mice. RESULTS/INTERPRETATION: Deletion of the integrin α1 subunit inhibited the ability of chondrocytes to respond to a hypo-osmotic stress with [Ca(2+)]i transients ex vivo and in vitro. The percentage of chondrocytes responding ex vivo was smaller than in vitro and of the cells that responded, more single [Ca(2+)]i transients were observed ex vivo compared to in vitro. Immunocytochemistry confirmed the presence of TRPV4 on wildtype and integrin α1-null chondrocytes, however application of GSK101 revealed that TRPV4 could be activated on wildtype but not integrin α1-null chondrocytes. Integrin α1ß1 is a key participant in chondrocyte transduction of a hypo-osmotic stress. Furthermore, the mechanism by which integrin α1ß1 influences osmotransduction is independent of matrix binding, but likely dependent on the chondrocyte osmosensor TRPV4.


Assuntos
Condrócitos/metabolismo , Integrina alfa1beta1/metabolismo , Pressão Osmótica/fisiologia , Transdução de Sinais/fisiologia , Animais , Cálcio/metabolismo , Células Cultivadas , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Feminino , Imuno-Histoquímica , Integrina alfa1beta1/genética , Leucina/análogos & derivados , Leucina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Microscopia Confocal , Sulfonamidas/farmacologia , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/metabolismo
10.
Osteoarthr Cartil Open ; 5(2): 100357, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37008821

RESUMO

Objective: Integrin α1ß1 protects against osteoarthritis when it is upregulated in the early stages of disease, however, the mechanism behind this is currently unknown. Hypo-osmotic stress, interleukin-1 (IL-1) and transforming growth factor ß (TGFß) influence chondrocyte signaling and are important mediators of osteoarthritis. Evidence for primary cilia as a signaling hub for these factors and the involvement of the F-actin cytoskeleton in this response is growing. The purpose of this study was to investigate the role of integrin α1ß1 in the response of primary cilia and the F-actin cytoskeleton to these osteoarthritic mediators. Design: Primary cilia length and the number of F-actin peaks were measured in ex vivo wild type and itga1-null chondrocytes in response to hypo-osmotic stress, IL-1, and TGFß alone or in combination, and with or without focal adhesion kinase inhibitor. Results: We show that integrin α1ß1 and focal adhesions are necessary for cilial lengthening and increases in F-actin peaks with hypo-osmotic stress and IL-1, but are not required for cilial shortening with TGFß. Furthermore, we established that the chondrocyte primary cilium has a resting length of 2.4 â€‹µm, a minimum length of 2.1 â€‹µm corresponding to the thickness of the pericellular matrix, and a maximum length of 3.0 â€‹µm. Conclusions: While integrin α1ß1 is not necessary for the formation of chondrocyte primary cilia and cilial shortening in response to TGFß, it is necessary for the mediation of cilial lengthening and the formation of F-actin peaks in response to hypo-osmotic stress and IL-1.

11.
J Orthop Surg Res ; 18(1): 170, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879303

RESUMO

BACKGROUND: Osteoarthritis (OA) is a debilitating disease involving cartilage degradation. A need remains for the discovery of new molecular targets in cartilage for pharmaceutical intervention of OA. One potential target is integrin α1ß1 that protects against OA when it is upregulated by chondrocytes early in the disease process. Integrin α1ß1 offers this protection by dampening epidermal growth factor receptor (EGFR) signaling, and its effects are more robust in females compared to males. The aim of this study, therefore, was to measure the impact of itga1 on chondrocyte EGFR activity and downstream reactive oxygen species (ROS) production in male and female mice. Furthermore, chondrocyte expression of estrogen receptor (ER) α and ERß was measured to investigate the mechanism for sexual dimorphism in the EGFR/integrin α1ß1 signaling axis. We hypothesized that integrin α1ß1 would decrease ROS production and pEGFR and 3-nitrotyrosine expression, with this effect being greater in females. We further hypothesized that chondrocyte expression of ERα and ERß would be greater in females compared to males, with a greater effect seen in itga1-null compared to wild-type mice. MATERIALS AND METHODS: Femoral and tibial cartilage of male and female, wild-type and itga1-null mice were processed for ex vivo confocal imaging of ROS, immunohistochemical analysis of 3-nitrotyrosine, or immunofluorescence of pEGFR and ERα and ERß. RESULTS: We show that ROS-producing chondrocytes are more abundant in female itga1-null compared to wild-type mice ex vivo; however, itga1 had limited influence on the percent of chondrocytes stained positively for 3-nitrotyrosine or pEGFR in situ. In addition, we found that itga1 influenced ERα and ERß expression in femoral cartilage from female mice, and that ERα and ERß were coexpressed as well as colocalized in chondrocytes. Finally, we show sexual dimorphism in ROS and 3-nitrotyrosine production, but surprisingly not in pEGFR expression. CONCLUSIONS: Together these data highlight sexual dimorphism in the EGFR/integrin α1ß1 signaling axis and underline the need for further investigation into the role of ERs in this biological paradigm. Understanding the molecular mechanisms underlying the development of OA is essential for the development of individualized, sex-specific treatments in this age of personalized medicine.


Assuntos
Cartilagem Articular , Osteoartrite , Feminino , Masculino , Animais , Camundongos , Receptor alfa de Estrogênio/genética , Espécies Reativas de Oxigênio , Integrina alfa1beta1 , Caracteres Sexuais , Receptor beta de Estrogênio/genética , Receptores ErbB , Camundongos Knockout , Osteoartrite/genética
12.
Osteoarthr Cartil Open ; 5(4): 100399, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37649532

RESUMO

Objectives: Integrin α1ß1 protects against osteoarthritis (OA) when it is upregulated in the superficial zone of cartilage in the early stages of disease. However, the mechanism behind this protection is unknown. Integrin α1ß1 moderates transforming growth factor ß receptor II (TGFBR2) signalling, a critical regulator of chondrocyte anabolic activity. To this end, mice lacking integrin α1ß1 have increased baseline activation of TGFBR2 signalling and overall fibrosis. The purpose of this study was to evaluate the interplay between integrin α1ß1 and TGFBR2 in the development of spontaneous OA. We hypothesized that dampening TGFBR2 signalling in the cartilage of itga1-null mice would attenuate OA. Methods: Behavioural and histological manifestations of spontaneous knee OA were measured at 4, 8, 12 and 16 months in mice with and without a ubiquitous itga1 deletion and with and without a tamoxifen-induced cartilage specific TGFBR2 depletion. Results: Knee cartilage degeneration, collateral ligament ossification and pain responses increased with age. Itga1-null mice with intact TGFBR2 signalling developed earlier and more severe OA compared to controls. In agreement with our hypothesis, depleting TGFBR2 signalling in the cartilage of itga1-null mice attenuated OA progression. Conclusion: Intact TGFBR2 signalling drives early and worse knee OA in itga1-null mice. This result supports the hypothesis that the increased expression of integrin α1ß1 by superficial zone chondrocytes early in OA development dampens TGFBR2 signalling and thus protects against degeneration.

13.
Biomolecules ; 13(4)2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37189414

RESUMO

Intrinsically disordered proteins play important roles in cell signaling, and dysregulation of these proteins is associated with several diseases. Prostate apoptosis response-4 (Par-4), an approximately 40 kilodalton proapoptotic tumor suppressor, is a predominantly intrinsically disordered protein whose downregulation has been observed in various cancers. The caspase-cleaved fragment of Par-4 (cl-Par-4) is active and plays a role in tumor suppression by inhibiting cell survival pathways. Here, we employed site-directed mutagenesis to create a cl-Par-4 point mutant (D313K). The expressed and purified D313K protein was characterized using biophysical techniques, and the results were compared to that of the wild-type (WT). We have previously demonstrated that WT cl-Par-4 attains a stable, compact, and helical conformation in the presence of a high level of salt at physiological pH. Here, we show that the D313K protein attains a similar conformation as the WT in the presence of salt, but at an approximately two times lower salt concentration. This establishes that the substitution of a basic residue for an acidic residue at position 313 alleviates inter-helical charge repulsion between dimer partners and helps to stabilize the structural conformation.


Assuntos
Proteínas Intrinsicamente Desordenadas , Neoplasias , Masculino , Humanos , Conformação Proteica , Modelos Moleculares , Genes Supressores de Tumor , Mutagênese Sítio-Dirigida , Proteínas Intrinsicamente Desordenadas/química , Dicroísmo Circular
14.
J Orthop ; 32: 104-108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35668833

RESUMO

Objective: Osteoarthritis (OA) is a degenerative joint disease that is more prevalent in women than men, especially later in life. This suggests that sexual dimorphism may be present in the pathogenesis of the disease. The purpose of this review is to discuss evidence of sexual dimorphism in knee OA development and presentation as it is framed by two contrasting paradigms: biomechanics and biology. Methods: A comprehensive search of databases was conducted including, but not limited to, MEDLINE via Ovid, PubMed, and Google Scholar. Keywords including osteoarthritis, sex differences, and/or sexual dimorphism were searched in combination with knee biomechanics, ACL, joint malalignment, estrogen, chondrocyte signal(l)ing, growth factor and integrin(s). Results: The biomechanical approach has identified sex differences in joint malalignment, bone shape, gait, and lower limb muscle strength leading to altered load transmission, as well as increased knee laxity in women predisposing them to joint injury. The biological approach has largely focused on the influence of estrogen receptor signaling on the maintenance of joint tissues. Preliminary work identifying sexual dimorphism in chondrocyte signaling pathways involving growth factors and collagen receptors has been reported in addition to more systemic levels of inflammatory cytokines and metabolites. Conclusion: Understanding the true etiology of OA is crucial for developing effective, individualized treatment in the age of personalised medicine. A shift from a 'one size fits all' mentality towards an individualized approach for therapeutic treatment must begin with the acknowledgment of sex differences in the biomechanical and biological factors underlying the onset and development of OA.

15.
Arthritis Rheum ; 62(10): 2973-83, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20583100

RESUMO

OBJECTIVE: Mechanical loading significantly influences the physiology and pathology of articular cartilage, although the mechanisms of mechanical signal transduction are not fully understood. Transient receptor potential vanilloid 4 (TRPV4) is a Ca(++)-permeable ion channel that is highly expressed by articular chondrocytes and can be gated by osmotic and mechanical stimuli. The goal of this study was to determine the role of Trpv4 in the structure of the mouse knee joint and to determine whether Trpv4(-/-) mice exhibit altered Ca(++) signaling in response to osmotic challenge. METHODS: Knee joints of Trpv4(-/-) mice were examined histologically and by microfocal computed tomography for osteoarthritic changes and bone structure at ages 4, 6, 9, and 12 months. Fluorescence imaging was used to quantify chondrocytic Ca(++) signaling within intact femoral cartilage in response to osmotic stimuli. RESULTS: Deletion of Trpv4 resulted in severe osteoarthritic changes, including cartilage fibrillation, eburnation, and loss of proteoglycans, that were dependent on age and male sex. Subchondral bone volume and calcified meniscal volume were greatly increased, again in male mice. Chondrocytes from Trpv4(+/+) mice demonstrated significant Ca(++) responses to hypo-osmotic stress but not to hyperosmotic stress. The response to hypo-osmotic stress or to the TRPV4 agonist 4α-phorbol 12,13-didecanoate was eliminated in Trpv4(-/-) mice. CONCLUSION: Deletion of Trpv4 leads to a lack of osmotically induced Ca(++) signaling in articular chondrocytes, accompanied by progressive, sex-dependent increases in bone density and osteoarthritic joint degeneration. These findings suggest a critical role for TRPV4-mediated Ca(++) signaling in the maintenance of joint health and normal skeletal structure.


Assuntos
Cartilagem Articular/fisiopatologia , Condrócitos/fisiologia , Articulação do Joelho/fisiopatologia , Osteoartrite/fisiopatologia , Transdução de Sinais/fisiologia , Canais de Cátion TRPV/fisiologia , Animais , Artrite Experimental , Densidade Óssea/fisiologia , Feminino , Masculino , Camundongos , Pressão Osmótica/fisiologia , Fatores Sexuais , Canais de Cátion TRPV/deficiência
16.
J Community Health ; 36(1): 23-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20496001

RESUMO

The current study was designed to evaluate a unique adolescent peer type 2 diabetes mellitus (Type 2 DM) prevention training program for fifth grade children. Peer educators were 22 high school students who participated in the Elementary Institute of Science's Commission on Science that Matters, a year-long program promoting active participation in the health and environmental sciences. Peer education was delivered in the form of a two hour health fair. A knowledge survey was given to fifth grade students in the classroom before the health fair began and then again in the classroom after the health fair. Fifth grade students were able to correctly identify Type 1 DM (23 vs. 40%; P < .01), Type 2 DM (21 vs. 52%; P < .001), and the signs of diabetes (10 vs. 39%; P < .001) after the health fair. This approach could be inexpensively integrated into any community-based health promotion with children and adolescents.


Assuntos
Diabetes Mellitus Tipo 2/prevenção & controle , Exposições Educativas , Conhecimentos, Atitudes e Prática em Saúde , Grupo Associado , Ensino/métodos , Adolescente , Negro ou Afro-Americano/educação , Criança , Diabetes Mellitus , Feminino , Hispânico ou Latino/educação , Humanos , Masculino , Pobreza , Avaliação de Programas e Projetos de Saúde , Estudantes , Inquéritos e Questionários
17.
Exp Gerontol ; 149: 111311, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33744392

RESUMO

Naturally occurring spine osteoarthritis is clinically associated with the manifestation of chronic inflammatory muscle (myofascial) disease. The purpose of this study was to investigate the causal association between experimentally induced spine osteoarthritis and neurogenic inflammatory responses within neurosegmentally linked myotomes. Wistar Kyoto rats were randomly assigned to spine facet compression surgery (L4-L6) or sham surgery. Animals exposed to facet compression surgery demonstrated radiographic signs of facet-osteoarthritis (L4-L6 spinal levels) and sensory changes (allodynia, thermal hyperalgesia) at 7, 14 and 21 days post-intervention, consistent with the induction of central sensitization; no radiologic or sensory changes were observed after sham surgery. Increased levels of proinflammatory biomarkers including substance P (SP), calcitonin gene related peptide (CGRP), protease-activated receptor-2 (PAR2) and calcium/calmodulin dependent protein kinase II (CaMKII) were observed post-surgery within neurosegmentally-linked rectus femoris (L2-L5) muscle when compared to the non-segmentally linked biceps brachii (C4-C7) muscle; no differences were observed between muscles in the sham surgery group. These findings offer novel insight into the potential role of spine osteoarthritis and neurogenic inflammatory mechanisms in the pathophysiology of chronic inflammatory muscle (myofascial) disease.


Assuntos
Osteoartrite da Coluna Vertebral , Animais , Peptídeo Relacionado com Gene de Calcitonina , Hiperalgesia , Inflamação Neurogênica , Ratos , Ratos Sprague-Dawley , Substância P
18.
Front Neuroanat ; 15: 628711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33737870

RESUMO

Afferent neurons and their mechanoreceptors provide critical sensory feedback for gait. The anatomical distribution and density of afferents and mechanoreceptors influence sensory feedback, as does mechanoreceptor function. Electrophysiological studies of hind paw skin reveal the different types of afferent responses and their receptive fields, however, the anatomical distribution of mechanoreceptor endings is unknown. Also, the role of integrin α1ß1 in mechanoreceptor function is unclear, though it is expressed by keratinocytes in the stratum basale where it is likely involved in a variety of mechanotransduction pathways and ion channel functionalities. For example, it has been shown that integrin α1ß1 is necessary for the function of TRPV4 that is highly expressed by afferent units. The purpose of this study, therefore, was to determine and compare the distribution of mechanoreceptors across the hind paw skin and the footfall patterns of itga1-null and wild type mice. The itga1-null mouse is lacking the integrin α1 subunit, which binds exclusively to the ß1 subunit, thus rendering integrin α1ß1 nonfunctional while leaving the numerous other pairings of the ß1 subunit undisturbed. Intact hind paws were processed, serially sectioned, and stained to visualize mechanoreceptors. Footfall patterns were analyzed as a first step in correlating mechanoreceptor distribution and functionality. Merkel cells and Meissner-like corpuscles were present, however, Ruffini endings and Pacinian corpuscles were not observed. Meissner-like corpuscles were located exclusively in the glabrous skin of the footpads and digit tips, however, Merkel cells were found throughout hairy and glabrous skin. The increased density of Merkel cells and Meissner-like corpuscles in footpads 1 and 3 and Meissner-like corpuscles in footpad 4 suggests their role in anteroposterior balance, while Meissner-like corpuscle concentrations in digits 2 and 5 support their role in mediolateral balance. Finally, a larger density of Meissner-like corpuscles in footpads 3 and 4 in male itga1-null mice compared to wild type controls paves the way for future site-specific single fiber in vivo recordings to provide insight into the role of integrin α1ß1 in tactile mechanotransduction.

19.
JMIR Hum Factors ; 8(1): e24055, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33666555

RESUMO

BACKGROUND: Recruitment processes for clinical trials of digital interventions for psychosis are seldom described in detail in the literature. Although trial staff have expertise in describing barriers to and facilitators of recruitment, a specific focus on understanding recruitment from the point of view of trial staff is rare, and because trial staff are responsible for meeting recruitment targets, a lack of research on their point of view is a key limitation. OBJECTIVE: The primary aim of this study was to understand recruitment from the point of view of trial staff and discover what they consider important. METHODS: We applied pluralistic ethnographic methods, including analysis of trial documents, observation, and focus groups, and explored the recruitment processes of the EMPOWER (Early Signs Monitoring to Prevent Relapse in Psychosis and Promote Well-being, Engagement, and Recovery) feasibility trial, which is a digital app-based intervention for people diagnosed with schizophrenia. RESULTS: Recruitment barriers were categorized into 2 main themes: service characteristics (lack of time available for mental health staff to support recruitment, staff turnover, patient turnover [within Australia only], management styles of community mental health teams, and physical environment) and clinician expectations (filtering effects and resistance to research participation). Trial staff negotiated these barriers through strategies such as emotional labor (trial staff managing feelings and expressions to successfully recruit participants) and trying to build relationships with clinical staff working within community mental health teams. CONCLUSIONS: Researchers in clinical trials for digital psychosis interventions face numerous recruitment barriers and do their best to work flexibly and to negotiate these barriers and meet recruitment targets. The recruitment process appeared to be enhanced by trial staff supporting each other throughout the recruitment stage of the trial.

20.
Cancer Immunol Immunother ; 59(1): 149-59, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19593564

RESUMO

Ca(2+) messages are broadly important in cellular signal transduction. In immune cells, Ca(2+) signaling is an essential step in many forms of activation. Neutrophil-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) is one form of leukocyte activation that plays an important role in tumor cell killing in vitro and in patient care. Using fluorescence methodologies, we found that neutrophils exhibit Ca(2+) signals during ADCC directed against breast fibrosarcoma cells. Importantly, these signals were localized to Ca(2+) microdomains at the neutrophil-to-tumor cell interface where they display dynamic features such as movement, fusion, and fission. These signals were blocked by the intracellular Ca(2+) buffer BAPTA. At the neutrophil-tumor cell synapse, the neutrophil's cytoplasm was enriched in STIM1, a crucial mediator of Ca(2+) signaling, whereas the Ca(2+)-binding proteins calbindin and parvalbumin were not affected. Our findings suggest that Ca(2+) microdomains are due to an active signaling process. As Ca(2+) signals within neutrophils were necessary for specific tumor cell apoptosis, a central role of microdomains in leukocyte-mediated tumor cell destruction is indicated.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Apoptose/imunologia , Cálcio/fisiologia , Junções Intercelulares/fisiologia , Microdomínios da Membrana/fisiologia , Neutrófilos/imunologia , Neoplasias da Mama , Canais de Cálcio , Adesão Celular , Fusão Celular , Linhagem Celular Tumoral , Feminino , Fibrossarcoma , Humanos , Ativação Linfocitária , Glicoproteínas de Membrana/imunologia , Neutrófilos/fisiologia , Molécula 1 de Interação Estromal
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