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BACKGROUND: Evidence-based programs (EBPs) for older adults effectively improve health outcomes. However, there is a limited understanding of the unique needs of service providers as they consider adopting, implementing, and maintaining programs for older minority adults in low-income communities with limited aging services. METHODS: We conducted semi-structured interviews with key informants of community-based organizations (CBOs) to understand implementation and sustainability needs of CBOs within four racial and ethnically diverse Los Angeles County geographic areas. We performed thematic analysis of interview transcripts. RESULTS: Interviews were conducted with representatives from 25 senior-serving agencies providing aging-related EBPs. CBO representatives reported implementing EBPs in 8 domains: Falls Prevention (68%), Mental Health (64%), Caregiver Health (48%), Chronic Disease Management (48%), Diabetes Management (36%), Arthritis Management (28%), Physical Activity (24%), and Multiple Conditions Management (8%). Themes are presented using the six domains of the Bass and Judge framework for factors impacting successful and sustained EBP implementation. CBOs in low-income and diverse communities described unique challenges with tailoring interventions based on local community context (literacy, language), cultural context, and locally available resources (technology, safe community spaces, transportation) and faced resource-intensive administrative burdens through staff turnover, data collection, sustainable funding, and networking. CONCLUSIONS: Serving racial and ethnic communities has unique challenges that require tailored approaches and additional resources to ensure equitable access to EBPs for all communities. We describe suggestions for enhancing the effective adoption of EBPs among service agencies in under-resourced and diverse aging communities serving populations with aging-related health disparities.
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Artritis , Grupos Raciales , Humanos , Anciano , Envejecimiento , Terapia Conductista , Recolección de DatosRESUMEN
Persson and Savulescu argue that moral bioenhancement is not only morally permissible; in some cases, it is morally obligatory. In this article, I introduce a new reason to worry about moral enhancement. I adapt the disability concept of misfit to show how moral enhancement could cause extreme moral disempowerment to those enhanced, which would result in moral injury. I argue that any safety framework that guides the development of moral bioenhancement must be sensitive to the problem of moral misfitting. I present the best case for moral bioenhancement before turning to my own worry concerning the development of moral bioenhancement and its practical implications. Finally, I consider a series of objections and responses.
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Refuerzo Biomédico , Humanos , Principios MoralesRESUMEN
OBJECTIVE: To develop EULAR points-to-consider for therapeutic drug monitoring (TDM) of biopharmaceuticals in inflammatory rheumatic and musculoskeletal diseases (RMDs). METHODS: The points-to-consider were developed in accordance with EULAR standardised operation procedures by a multidisciplinary task force from eight European countries, based on a systematic literature review and expert consensus. Level of evidence and strength of the points-to-consider were determined, and mean levels of agreement among the task force were calculated using a 10-point rating scale. RESULTS: Six overarching principles and 13 points-to-consider were formulated. The level of agreement among the task force for the overarching principles and points-to-consider ranged from 8.4 to 9.9.The overarching principles define TDM and its subtypes, and reinforce the underlying pharmacokinetic/pharmacodynamic principles, which are relevant to all biopharmaceutical classes. The points-to-consider highlight the clinical utility of the measurement and interpretation of biopharmaceutical blood concentrations and antidrug antibodies in specific clinical scenarios, including factors that influence these parameters. In general, proactive use of TDM is not recommended but reactive TDM could be considered in certain clinical situations. An important factor limiting wider adoption of TDM is the lack of both high quality trials addressing effectiveness and safety of TDM and robust economic evaluation in patients with RMDs. Future research should focus on providing this evidence, as well as on further understanding of pharmacokinetic and pharmacodynamic characteristics of biopharmaceuticals. CONCLUSION: These points-to-consider are evidence-based and consensus-based statements for the use of TDM of biopharmaceuticals in inflammatory RMDs, addressing the clinical utility of TDM.
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Productos Biológicos , Enfermedades Musculoesqueléticas , Enfermedades Reumáticas , Humanos , Productos Biológicos/uso terapéutico , Monitoreo de Drogas , Enfermedades Musculoesqueléticas/tratamiento farmacológico , Anticuerpos , Europa (Continente) , Enfermedades Reumáticas/tratamiento farmacológicoRESUMEN
BACKGROUND: Breastfeeding and postpartum contraception critically influence infant and maternal health outcomes. In this pilot study, we explore the effects of timing and duration of postpartum levonorgestrel exposure on milk lipid and levonorgestrel content to establish baseline data for future research. METHODS: This sub-study recruited a balanced convenience sample from 259 participants enrolled in a parent randomized controlled trial comparing immediate to delayed (4-8 weeks) postpartum levonorgestrel IUD placement. All planned to breastfeed, self-selected for sub-study participation, and provided the first sample at 4-8 weeks postpartum (before IUD placement for the delayed group) and the second four weeks later. We used the Wilcoxon rank sum (inter-group) and signed rank (intra-group) tests to compare milk lipid content (creamatocrit) and levonorgestrel levels between groups and time points. RESULTS: We recruited 15 participants from the immediate group and 17 from the delayed group with 10 and 12, respectively, providing both early and late samples. Initially, median levonorgestrel concentration of the immediate group (n = 10) (32.5 pg/mL, IQR: 24.8, 59.4) exceeded that of the delayed group (n = 12) (17.5 pg/mL, IQR: 0.0, 25.8) (p = 0.01). Four weeks later, the values aligned: 26.2 pg/mL (IQR: 20.3, 37.3) vs. 28.0 pg/mL (IQR: 25.2, 40.8). Creamatocrits were similar between both groups and timepoints. CONCLUSIONS: Immediate postpartum levonorgestrel IUD placement results in steady, low levels of levonorgestrel in milk without apparent effects on lipid content. These findings provide initial support for the safety of immediate postpartum levonorgestrel IUD initiation, though the study was not powered to detect noninferiority between groups. TRIAL REGISTRATION: This randomized controlled trial was registered with ClinicalTrials.gov (Registry No. NCT01990703) on November 21, 2013.
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Anticonceptivos Femeninos , Levonorgestrel , Animales , Anticonceptivos Femeninos/uso terapéutico , Femenino , Humanos , Lactante , Leche , Proyectos Piloto , Periodo PospartoRESUMEN
The Fanconi Anemia (FA) pathway is important for repairing interstrand crosslinks (ICLs) between the Watson-Crick strands of the DNA double helix. An initial and essential stage in the repair process is the detection of the ICL. Here, we report the identification of UHRF2, a paralogue of UHRF1, as an ICL sensor protein. UHRF2 is recruited to ICLs in the genome within seconds of their appearance. We show that UHRF2 cooperates with UHRF1, to ensure recruitment of FANCD2 to ICLs. A direct protein-protein interaction is formed between UHRF1 and UHRF2, and between either UHRF1 and UHRF2, and FANCD2. Importantly, we demonstrate that the essential monoubiquitination of FANCD2 is stimulated by UHRF1/UHRF2. The stimulation is mediating by a retention of FANCD2 on chromatin, allowing for its monoubiquitination by the FA core complex. Taken together, we uncover a mechanism of ICL sensing by UHRF2, leading to FANCD2 recruitment and retention at ICLs, in turn facilitating activation of FANCD2 by monoubiquitination.
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Reparación del ADN/fisiología , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/fisiología , Ubiquitina-Proteína Ligasas/fisiología , Secuencia de Aminoácidos , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/fisiología , Línea Celular , Núcleo Celular/metabolismo , Cromatina/metabolismo , ADN/metabolismo , Daño del ADN/fisiología , Anemia de Fanconi/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/metabolismo , Proteínas del Grupo de Complementación de la Anemia de Fanconi/genética , Células HEK293 , Células HeLa , Humanos , Dominios y Motivos de Interacción de Proteínas , Ubiquitina-Proteína Ligasas/metabolismo , UbiquitinaciónRESUMEN
Of the two human herpesvirus 6 (HHV-6) species, human herpesvirus 6B (HHV-6B) encephalitis is an important cause of morbidity and mortality after allogeneic hematopoietic stem cell transplant. Guidelines for the management of HHV-6 infections in patients with hematologic malignancies or post-transplant were prepared a decade ago but there have been no other guidelines since then despite significant advances in the understanding of HHV-6 encephalitis, its therapy, and other aspects of HHV-6 disease in this patient population. Revised guidelines prepared at the 2017 European Conference on Infections in Leukaemia covering diagnosis, preventative strategies and management of HHV-6 disease are now presented.
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Neoplasias Hematológicas/complicaciones , Herpesvirus Humano 6 , Guías de Práctica Clínica como Asunto , Infecciones por Roseolovirus/diagnóstico , Infecciones por Roseolovirus/etiología , Infecciones por Roseolovirus/terapia , Antivirales/farmacología , Antivirales/uso terapéutico , Transformación Celular Viral , Terapia Combinada , Europa (Continente) , Enfermedad Injerto contra Huésped/etiología , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Huésped Inmunocomprometido , Resultado del TratamientoRESUMEN
OBJECTIVES: Ethnic/racial minority groups are less likely to discuss issues involving end-of-life treatment preferences and utilize palliative care or hospice services. Some barriers may be differences in language, religion, lower levels of health literacy, or less access to healthcare services and information. The purpose of this article is to conduct a systematic review on interventional studies that investigated methods to overcome the barriers faced by ethnic/racial minorities when accessing end-of-life services, including completing advanced directives, accepting palliative care, and enrolling in hospice. METHODS: Literature searches using four standard scientific search engines were conducted to retrieve articles detailing original research in an interventional trial design. All studies were conducted in an outpatient setting, including primary care visits, home visits, and dialysis centers. Target populations were those identified from ethnic or racial minorities. RESULTS: Nine articles were selected to be included in the final review. All were full-text English language articles, with target populations including African Americans, Hispanic or Latinos, and Asian or Pacific Islanders. Measured outcomes involved level of comfort in discussing and knowledge of palliative care services, desire for aggressive care at the end-of-life, completion of advance directives, and rate of enrollment in hospice. SIGNIFICANCE OF RESULTS: Three main avenues of interventions included methods to enhance patient education, increase access to healthcare, or improve communication to establish better rapport with target population. Studies indicate that traditional delivery of healthcare services may be insufficient to recruit patients from ethnic/racial minorities, and outcomes can be improved by implementing tailored interventions to overcome barriers.
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Etnicidad/psicología , Cuidados Paliativos/métodos , Pueblo Asiatico/etnología , Pueblo Asiatico/psicología , Población Negra/etnología , Población Negra/psicología , Disparidades en Atención de Salud/etnología , Hispánicos o Latinos/psicología , Humanos , Cuidados Paliativos/psicología , Cuidados Paliativos/normasRESUMEN
The bioactive sphingolipid, ceramide 1-phosphate (C-1-P), has been implicated as an extracellular chemotactic agent directing cellular migration in hematopoietic stem/progenitor cells and macrophages. However, interacting proteins that could mediate these actions of C-1-P have, thus far, eluded identification. We have now identified and characterized interactions between ceramide 1-phosphate and the annexin a2-p11 heterotetramer constituents. This C-1-P-receptor complex is capable of facilitating cellular invasion. Herein, we demonstrate in both coronary artery macrovascular endothelial cells and retinal microvascular endothelial cells that C-1-P induces invasion through an extracellular matrix barrier. By employing surface plasmon resonance, lipid-binding ELISA, and mass spectrometry technologies, we have demonstrated that the heterotetramer constituents bind to C-1-P. Although the annexin a2-p11 heterotetramer constituents do not bind the lipid C-1-P exclusively, other structurally similar lipids, such as phosphatidylserine, sphingosine 1-phosphate, and phosphatidic acid, could not elicit the potent chemotactic stimulation observed with C-1-P. Further, we show that siRNA-mediated knockdown of either annexin a2 or p11 protein significantly inhibits C-1-P-directed invasion, indicating that the heterotetrameric complex is required for C-1-P-mediated chemotaxis. These results imply that extracellular C-1-P, acting through the extracellular annexin a2-p11 heterotetrameric protein, can mediate vascular endothelial cell invasion.
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Anexina A2/metabolismo , Ceramidas/metabolismo , Quimiotaxis/fisiología , Células Endoteliales/metabolismo , Complejos Multiproteicos/metabolismo , Proteínas S100/metabolismo , Células Cultivadas , Matriz Extracelular/metabolismo , HumanosRESUMEN
BACKGROUND: The use of a cytomegalovirus (CMV)-seronegative donor for a CMV-seronegative allogeneic hematopoietic stem cell transplant (HSCT) recipient is generally accepted. However, the importance of donor serostatus in CMV-seropositive patients is controversial. METHODS: A total of 49 542 HSCT patients, 29 349 seropositive and 20 193 seronegative, were identified from the European Group for Blood and Marrow Transplantation database. Cox multivariate models were fitted to estimate the effect of donor CMV serological status on outcome. RESULTS: Seronegative patients receiving seropositive unrelated-donor grafts had decreased overall survival (hazard ratio [HR], 1.13; 95% confidence interval [CI], 1.06-1.21; P < .0001) compared with seronegative donors, whereas no difference was seen in patients receiving HLA-matched sibling grafts. Seropositive patients receiving grafts from seropositive unrelated donors had improved overall survival (HR, 0.92; 95% CI, .86-.98; P < .01) compared with seronegative donors, if they had received myeloablative conditioning. This effect was absent when they received reduced-intensity conditioning. No effect was seen in patients grafted from HLA-identical sibling donors. The same association was found if the study was limited to patients receiving transplants from the year 2000 onward. CONCLUSIONS: We confirm the negative impact on overall survival if a CMV-seropositive unrelated donor is selected for a CMV-seronegative patient. For a CMV-seropositive patient, our data support selecting a CMV-seropositive donor if the patient receives a myeloablative conditioning regimen.
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Infecciones por Citomegalovirus/inmunología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Donantes de Tejidos , Trasplante Homólogo/efectos adversos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Acondicionamiento Pretrasplante , Resultado del Tratamiento , Adulto JovenRESUMEN
PURPOSE OF REVIEW: This review evaluates publications on human herpesvirus 6 (HHV-6) encephalitis recognizing firstly that HHV-6A and HHV-6B are separate species with differing properties, and secondly the phenomenon of chromosomal integration; this occurs in a minority of persons and the complete viral genome of either HHV-6A or HHV-6B is present in every nucleated cell in the body. Although chromosomal integration has not been associated with disease, the resulting very high level of viral DNA in human tissues and blood has sometimes been wrongly misinterpreted as active infection. RECENT FINDINGS: No disease has been linked to HHV-6A, whereas HHV-6B may cause encephalitis. Encephalitis due to primary HHV-6B infection in young children is commonly reported from Japan, but very rarely elsewhere in the world, suggesting a genetic predisposition. Reports of HHV-6A or HHV-6B encephalitis in immunocompetent older children/adults are most likely due to chromosomal integration and not active infection. HHV-6B reactivation is well established as causing limbic encephalitis after haematopoietic stem cell transplantation, particularly after receipt of cord blood; the outcome is poor and preventive strategies are ineffective. SUMMARY: Understanding the pathophysiology of HHV-6B encephalitis remains incomplete, especially regarding young children. Clinical trials of antiviral therapy are warranted for treatment and prevention of HHV-6B encephalitis after transplantation.
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ADN Viral , Encefalitis Viral/inmunología , Herpesvirus Humano 6/genética , Huésped Inmunocomprometido/inmunología , Infecciones por Roseolovirus/inmunología , Adulto , Pueblo Asiatico/genética , Niño , Encefalitis Viral/epidemiología , Encefalitis Viral/genética , Predisposición Genética a la Enfermedad , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Inmunosupresores/uso terapéutico , Infecciones por Roseolovirus/epidemiología , Infecciones por Roseolovirus/genéticaRESUMEN
BACKGROUND: Prior to initiating immunosuppressive therapy in the treatment of autoimmune inflammatory conditions, it is a requirement to screen for certain viral serology, including hepatitis B (HBV). A positive result may indicate the need for antiviral therapy, or contraindicate immunosuppression all together. An accurate interpretation of serological markers is therefore imperative in order to treat patients appropriately. We present a case of passive anti-HBV antibody transfer following intravenous immunoglobulin (IVIg) infusion, in which misinterpretation of serology results almost led to inappropriate treatment with antiviral therapy and the withholding of immunosuppressive agents. This phenomenon has been previously reported, but awareness remains limited. CASE PRESENTATION: A 50 year old Caucasian gentleman with a history of allogeneic haematopoietic stem cell transplant for transformed follicular lymphoma was admitted to hospital with recurrent respiratory tract infections. Investigation found him to be hypogammaglobulinaemic, and he was thus given 1 g/kg of intravenous immunoglobulin. The patient also disclosed a 3-week history of painful, swollen joints, leading to a diagnosis of seronegative inflammatory polyarthritis. Prior to initiating long term immunosuppression, viral screening found hepatitis B serology suggestive of past infection, with positive results for both anti-HBc and anti-HBs antibody, but negative HBV DNA. In response, prednisolone was weaned and the local hepatology team recommended commencement of lamivudine. Having been unable to identify a source of infection, the case was reported to the local blood centre, who tested a remaining vial from the same batch of IVIg and found it to be anti-HBc and anti-HBs positive. Fortunately the blood products were identified and tested prior to the patient initiating HBV treatment, and the effect of a delay in starting disease-modifying therapy was inconsequential in light of an excellent response to first-line therapies. CONCLUSION: Misinterpretation of serology results following IVIg infusion may lead to significant patient harm, including unnecessary antiviral administration, the withholding of treatments, and psychosocial damage. This is especially pertinent at a time when we have an ever increasing number of patients being treated with IVIg for a wide array of immune-mediated disease. Passive antibody transfer should be considered wherever unexpected serological changes are identified.
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Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Hepatitis B/diagnóstico , Inmunoglobulinas Intravenosas/efectos adversos , Errores Médicos , Antivirales/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunosupresores/uso terapéutico , Lamivudine/uso terapéutico , Linfoma Folicular/inmunología , Linfoma Folicular/terapia , Masculino , Persona de Mediana Edad , Pruebas SerológicasRESUMEN
The Centers of Medicare and Medicaid Services recently announced a new voluntary nationwide model. This model aims to provide comprehensive, standard care for people living with dementia and their unpaid caregivers and to enhance health equity in dementia care. However, little is known about the needs of older adults with dementia and their caregivers in a multiethnic and multicultural patient population of a safety net health system. The aim of this study is to include their voices. We conducted four focus groups in English and Spanish to investigate the common needs and barriers unique to the care of patients within the Los Angeles County healthcare system. Using qualitative, iterative analyses of the transcripts, we identified four domains of concern from the dyads (persons with dementia and their caregivers): need for education for dyad-centered care, barriers to resources, dyad safety, and caregiver burden and insight. These domains are interconnected, and the way this patient population experiences these domains may differ compared to those in well-resourced or predominantly English-speaking healthcare settings. Therefore, the identified domains serve as potential building blocks for dementia support programs inclusive of underserved, multicultural populations.
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OBJECTIVE: Tracheoinnominate artery fistulas (TIFs) are a rare but deadly complication of tracheostomy. Tracheoinnominate artery fistula cases in the literature were summarized in order to understand mortality associations. METHODS: MEDLINE was searched for studies reporting individual characteristics of patients with TIFs after tracheostomy, excluding cases without tracheostomy or with additional procedures at the tracheostomy site. This study followed PRISMA guidelines. RESULTS: 121 TIF patients from 18 case series and 46 case reports were included. The median age was 40 years, and 52.9% were male. The overall mortality rate was 64.5%. There were differences in mortality between cases that presented initially with vs without sentinel bleeding (odds ratio [OR] .34; CI [confidence interval] .16-.73; P = .006). The mortality rate also differed in whether or not the tracheostomy cuff was over-inflated for temporary hemostasis during resuscitation (OR 3.57 (CI 1.57-8.09); P = .002). Treatment compared to no treatment had lower mortality rates (OR .11 (CI 0.04-.32); P < .001); no differences were found if treatment was endovascular vs open surgical. CONCLUSIONS: Mortality is a major concern after detection of a TIF and resuscitation paired with endovascular or open surgical intervention is imperative. Rapidly investigating sentinel bleeds and intervening upon hemorrhage with temporary cuff over inflation may lead to improved outcomes.
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Traqueostomía , Fístula Vascular , Humanos , Masculino , Tronco Braquiocefálico/cirugía , Complicaciones Posoperatorias/mortalidad , Enfermedades de la Tráquea/etiología , Enfermedades de la Tráquea/mortalidad , Enfermedades de la Tráquea/cirugía , Traqueostomía/efectos adversos , Traqueostomía/métodos , Fístula Vascular/mortalidad , Fístula Vascular/etiología , Fístula Vascular/cirugíaRESUMEN
OBJECTIVE: To compare the quality of urinary incontinence (UI) care for women in the safety-net and nonsafety-net settings prior to referral to a specialist. METHODS: We performed a retrospective review of 200 women from two nonsafety-net hospitals and 188 women from two safety-net hospitals who were referred to Urogynecology and Reconstructive Surgery specialists for bothersome UI between March 2017 and March 2020. We evaluated the care that women received 12 months prior to referral, by measuring adherence to a set of previously developed quality indicators (QIs), for example, the performance of a urinalysis or pelvic exam. RESULTS: Women seen in safety-net hospitals were more likely to receive QI-compliant care than women in the nonsafety-net hospitals prior to referral, with 55.53% of appropriate care given in the safety-net vs 40.3% in the nonsafety-net setting (P <.01). Clinicians in the safety-net hospitals were more likely to adhere to QIs in patients with general, stress, and urgency incontinence. CONCLUSION: Women were more likely to receive timely, quality-based UI care in the safety net compared to the nonsafety-net setting. This may be in part due to aspects unique to the safety-net system, including an eConsult referral system, which guides referring clinicians in appropriate management steps that should be taken prior to the specialist visit, as well as women's health-focused primary care clinics.
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Background: To improve care of geriatric trauma patients, the American College of Surgeons (ACS) Trauma Quality Improvement Program (TQIP) updated guidelines in 2021. Amid geriatrician shortages in Southern California, 2 Los Angeles County safety net hospitals were tasked with creating a strategy to meet geriatric trauma guidelines despite constrained resources. Methods: All trauma patients ≥ 60 years admitted to a safety net hospital in Southern California were enrolled without exclusions (August 2022-April 2023). Primary outcome was frailty screening with documentation to identify older trauma patients at a high risk for adverse outcomes. Results: Needs assessment discovered no standardized process to identify high-risk geriatric patients, no geriatric care guidelines, and no inpatient geriatric consultation service. An action plan composed of a resident-led frailty screen resulted in identification of high-risk patients. Overall, 217 patients met criteria. Ninety-six patients (44%) successfully underwent frailty screening. Frailty screening compliance increased over the study, beginning at 37% capture in the first month and increasing to 81% in the final study month. After achieving nearly uniform frailty screening, a form was developed for the EMR for ease of documentation, data capture/tracking, and compliance monitoring. Discussion: In this study, creativity, collaboration, and resourcefulness allowed TQIP guideline implementation at 2 county hospitals. A systematic process is now in place to identify and triage high-risk geriatric trauma patients based on frailty screen to receive inpatient medicine consultation for medical comorbidity optimization. Continued interdisciplinary and interfacility collaboration will be crucial for continued delivery of the optimal care to older injured patients.
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Mejoramiento de la Calidad , Proveedores de Redes de Seguridad , Humanos , Anciano , Femenino , Masculino , California , Heridas y Lesiones/terapia , Evaluación Geriátrica , Anciano de 80 o más Años , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Fragilidad , Adhesión a Directriz , Los AngelesRESUMEN
Group IVA cytosolic phospholipase A2 (cPLA2α), which harbors an N-terminal lipid binding C2 domain and a C-terminal lipase domain, produces arachidonic acid from the sn-2 position of zwitterionic lipids such as phosphatidylcholine. The C2 domain has been shown to bind zwitterionic lipids, but more recently, the anionic phosphomonoester sphingolipid metabolite ceramide-1-phosphate (C1P) has emerged as a potent bioactive lipid with high affinity for a cationic patch in the C2 domain ß-groove. To systematically analyze the role that C1P plays in promoting the binding of cPLA2α-C2 to biological membranes, we employed biophysical measurements and cellular translocation studies along with mutagenesis. Biophysical and cellular translocation studies demonstrate that C1P specificity is mediated by Arg59, Arg6¹, and His6² (an RxRH sequence) in the C2 domain. Computational studies using molecular dynamics simulations confirm the origin of C1P specificity, which results in a spatial shift of the C2 domain upon membrane docking to coordinate the small C1P headgroup. Additionally, the hydroxyl group on the sphingosine backbone plays an important role in the interaction with the C2 domain, further demonstrating the selectivity of the C2 domain for C1P over phosphatidic acid. Taken together, this is the first study demonstrating the molecular origin of C1P recognition.
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Ceramidas/metabolismo , Fosfolipasas A2 Grupo IV/química , Fosfolipasas A2 Grupo IV/metabolismo , Calcio/metabolismo , Eicosanoides/metabolismo , Simulación de Dinámica Molecular , Unión ProteicaRESUMEN
Protein kinase Cθ (PKCθ) is a novel PKC that plays a key role in T lymphocyte activation. To understand how PKCθ is regulated in T cells, we investigated the properties of its N-terminal C2 domain that functions as an autoinhibitory domain. Our measurements show that a Tyr(P)-containing peptide derived from CDCP1 binds the C2 domain of PKCθ with high affinity and activates the enzyme activity of the intact protein. The Tyr(P) peptide also binds the C2 domain of PKCδ tightly, but no enzyme activation was observed with PKCδ. Mutations of PKCθ-C2 residues involved in Tyr(P) binding abrogated the enzyme activation and association of PKCθ with Tyr-phosphorylated full-length CDCP1 and severely inhibited the T cell receptor/CD28-mediated activation of a PKCθ-dependent reporter gene in T cells. Collectively, these studies establish the C2 domain of PKCθ as a Tyr(P)-binding domain and suggest that the domain may play a major role in PKCθ activation via its Tyr(P) binding.
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Isoenzimas/química , Péptidos/química , Fosfotirosina/química , Proteína Quinasa C/química , Activación Enzimática , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Péptidos/genética , Péptidos/metabolismo , Fosforilación/fisiología , Fosfotirosina/genética , Fosfotirosina/metabolismo , Unión Proteica/fisiología , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Proteína Quinasa C-delta/química , Proteína Quinasa C-delta/genética , Proteína Quinasa C-delta/metabolismo , Proteína Quinasa C-theta , Estructura Terciaria de ProteínaRESUMEN
Community-acquired respiratory virus (CARV) infections have been recognized as a significant cause of morbidity and mortality in patients with leukemia and those undergoing hematopoietic stem cell transplantation (HSCT). Progression to lower respiratory tract infection with clinical and radiological signs of pneumonia and respiratory failure appears to depend on the intrinsic virulence of the specific CARV as well as factors specific to the patient, the underlying disease, and its treatment. To better define the current state of knowledge of CARVs in leukemia and HSCT patients, and to improve CARV diagnosis and management, a working group of the Fourth European Conference on Infections in Leukaemia (ECIL-4) 2011 reviewed the literature on CARVs, graded the available quality of evidence, and made recommendations according to the Infectious Diseases Society of America grading system. Owing to differences in screening, clinical presentation, and therapy for influenza and adenovirus, ECIL-4 recommendations are summarized for CARVs other than influenza and adenovirus.
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Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/terapia , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/terapia , Virosis/diagnóstico , Virosis/terapia , Infecciones Comunitarias Adquiridas/etiología , Infecciones Comunitarias Adquiridas/prevención & control , Coronavirus , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia/complicaciones , Leucemia/terapia , Metapneumovirus , Paramyxovirinae , Guías de Práctica Clínica como Asunto , Virus Sincitiales Respiratorios , Infecciones del Sistema Respiratorio/etiología , Infecciones del Sistema Respiratorio/prevención & control , Rhinovirus , Virosis/etiología , Virosis/prevención & controlRESUMEN
Chromosomally integrated human herpesvirus 6 (ciHHV-6) is a condition in which the complete HHV-6 genome is integrated into the host germ line genome and is vertically transmitted in a Mendelian manner. The condition is found in less than 1% of controls in the USA and UK, but has been found at a somewhat higher prevalence in transplant recipients and other patient populations in several small studies. HHV-6 levels in whole blood that exceed 5.5 log10 copies/ml are strongly suggestive of ciHHV-6. Monitoring DNA load in plasma and serum is unreliable, both for identifying and for monitoring subjects with ciHHV-6 due to cell lysis and release of cellular DNA. High HHV-6 DNA loads associated with ciHHV-6 can lead to erroneous diagnosis of active infection. Transplant recipients with ciHHV-6 may be at increased risk for bacterial infection and graft rejection. ciHHV-6 can be induced to a state of active viral replication in vitro. It is not known whether ciHHV-6 individuals are put at clinical risk by the use of drugs that have been associated with HHV-6 reactivation in vivo or in vitro. Nonetheless, we urge careful observation when use of such drugs is indicated in individuals known to have ciHHV-6. Little is known about whether individuals with ciHHV-6 develop immune tolerance for viral proteins. Further research is needed to determine the role of ciHHV-6 in disease.
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Cromosomas Humanos/virología , Herpesvirus Humano 6/fisiología , Infecciones por Roseolovirus/virología , Integración Viral , Herpesvirus Humano 6/genética , Humanos , Infecciones por Roseolovirus/genéticaRESUMEN
BACKGROUND: Evidence-based medicine requires synthesis of research through rigorous and time-intensive systematic literature reviews (SLRs), with significant resource expenditure for data extraction from scientific publications. Machine learning may enable the timely completion of SLRs and reduce errors by automating data identification and extraction. METHODS: We evaluated the use of machine learning to extract data from publications related to SLRs in oncology (SLR 1) and Fabry disease (SLR 2). SLR 1 predominantly contained interventional studies and SLR 2 observational studies. Predefined key terms and data were manually annotated to train and test bidirectional encoder representations from transformers (BERT) and bidirectional long-short-term memory machine learning models. Using human annotation as a reference, we assessed the ability of the models to identify biomedical terms of interest (entities) and their relations. We also pretrained BERT on a corpus of 100,000 open access clinical publications and/or enhanced context-dependent entity classification with a conditional random field (CRF) model. Performance was measured using the F1 score, a metric that combines precision and recall. We defined successful matches as partial overlap of entities of the same type. RESULTS: For entity recognition, the pretrained BERT+CRF model had the best performance, with an F1 score of 73% in SLR 1 and 70% in SLR 2. Entity types identified with the highest accuracy were metrics for progression-free survival (SLR 1, F1 score 88%) or for patient age (SLR 2, F1 score 82%). Treatment arm dosage was identified less successfully (F1 scores 60% [SLR 1] and 49% [SLR 2]). The best-performing model for relation extraction, pretrained BERT relation classification, exhibited F1 scores higher than 90% in cases with at least 80 relation examples for a pair of related entity types. CONCLUSIONS: The performance of BERT is enhanced by pretraining with biomedical literature and by combining with a CRF model. With refinement, machine learning may assist with manual data extraction for SLRs.