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1.
J Shoulder Elbow Surg ; 33(1): 73-81, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37379964

RESUMEN

BACKGROUND: Instability after reverse shoulder arthroplasty (RSA) is one of the most frequent complications and remains a clinical challenge. Current evidence is limited by small sample size, single-center, or single-implant methodologies that limit generalizability. We sought to determine the incidence and patient-related risk factors for dislocation after RSA, using a large, multicenter cohort with varying implants. METHODS: A retrospective, multicenter study was performed involving 15 institutions and 24 American Shoulder and Elbow Surgeons members across the United States. Inclusion criteria consisted of patients undergoing primary or revision RSA between January 2013 and June 2019 with minimum 3-month follow-up. All definitions, inclusion criteria, and collected variables were determined using the Delphi method, an iterative survey process involving all primary investigators requiring at least 75% consensus to be considered a final component of the methodology for each study element. Dislocations were defined as complete loss of articulation between the humeral component and the glenosphere and required radiographic confirmation. Binary logistic regression was performed to determine patient predictors of postoperative dislocation after RSA. RESULTS: We identified 6621 patients who met inclusion criteria with a mean follow-up of 19.4 months (range: 3-84 months). The study population was 40% male with an average age of 71.0 years (range: 23-101 years). The rate of dislocation was 2.1% (n = 138) for the whole cohort, 1.6% (n = 99) for primary RSAs, and 6.5% (n = 39) for revision RSAs (P < .001). Dislocations occurred at a median of 7.0 weeks (interquartile range: 3.0-36.0 weeks) after surgery with 23.0% (n = 32) after a trauma. Patients with a primary diagnosis of glenohumeral osteoarthritis with an intact rotator cuff had an overall lower rate of dislocation than patients with other diagnoses (0.8% vs. 2.5%; P < .001). Patient-related factors independently predictive of dislocation, in order of the magnitude of effect, were a history of postoperative subluxations before radiographically confirmed dislocation (odds ratio [OR]: 19.52, P < .001), primary diagnosis of fracture nonunion (OR: 6.53, P < .001), revision arthroplasty (OR: 5.61, P < .001), primary diagnosis of rotator cuff disease (OR: 2.64, P < .001), male sex (OR: 2.21, P < .001), and no subscapularis repair at surgery (OR: 1.95, P = .001). CONCLUSION: The strongest patient-related factors associated with dislocation were a history of postoperative subluxations and having a primary diagnosis of fracture nonunion. Notably, RSAs for osteoarthritis showed lower rates of dislocations than RSAs for rotator cuff disease. These data can be used to optimize patient counseling before RSA, particularly in male patients undergoing revision RSA.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Luxaciones Articulares , Osteoartritis , Articulación del Hombro , Humanos , Masculino , Anciano , Femenino , Artroplastía de Reemplazo de Hombro/efectos adversos , Artroplastía de Reemplazo de Hombro/métodos , Articulación del Hombro/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Osteoartritis/cirugía , Luxaciones Articulares/cirugía , Rango del Movimiento Articular
2.
Clin Trials ; 20(5): 546-558, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37329282

RESUMEN

BACKGROUND/AIMS: We present and describe recruitment strategies implemented from 2013 to 2017 across 45 clinical sites in the United States, participating in the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study, an unmasked, randomized controlled trial evaluating four glucose-lowering medications added to metformin in individuals with type 2 diabetes mellitus (duration of diabetes <10 years). We examined the yield of participants recruited through Electronic Health Records systems compared to traditional recruitment methods to leverage access to type 2 diabetes patients in primary care. METHODS: Site selection criteria included availability of the study population, geographic representation, the ability to recruit and retain a diverse pool of participants including traditionally underrepresented groups, and prior site research experience in diabetes clinical trials. Recruitment initiatives were employed to support and monitor recruitment, such as creation of a Recruitment and Retention Committee, development of criteria for Electronic Health Record systems queries, conduct of remote site visits, development of a public screening website, and other central and local initiatives. Notably, the study supported a dedicated recruitment coordinator at each site to manage local recruitment and facilitate screening of potential participants identified by Electronic Health Record systems. RESULTS: The study achieved the enrollment goal of 5000 participants, meeting its target with Black/African American (20%), Hispanic/Latino (18%), and age ≧60 years (42%) subgroups but not with women (36%). Recruitment required 1 year more than the 3 years originally planned. Sites included academic hospitals, integrated health systems, and Veterans Affairs Medical Centers. Participants were enrolled through Electronic Health Record queries (68%), physician referral (13%), traditional mail outreach (7%), TV, radio, flyers, and Internet (7%), and other strategies (5%). Early implementation of targeted Electronic Health Record queries yielded a greater number of eligible participants compared to other recruitment methods. Efforts over time increasingly emphasized engagement with primary care networks. CONCLUSION: Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness successfully recruited a diverse study population with relatively new onset of type 2 diabetes mellitus, relying to a large extent on the use of Electronic Health Record to screen potential participants. A comprehensive approach to recruitment with frequent monitoring was critical to meet the recruitment goal.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metformina , Humanos , Femenino , Persona de Mediana Edad , Diabetes Mellitus Tipo 2/prevención & control , Selección de Paciente
3.
J Shoulder Elbow Surg ; 32(12): 2483-2492, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37330167

RESUMEN

BACKGROUND: Both patient and implant related variables have been implicated in the incidence of acromial (ASF) and scapular spine fractures (SSF) following reverse shoulder arthroplasty (RSA); however, previous studies have not characterized nor differentiated risk profiles for varying indications including primary glenohumeral arthritis with intact rotator cuff (GHOA), rotator cuff arthropathy (CTA), and massive irreparable rotator cuff tear (MCT). The purpose of this study was to determine patient factors predictive of cumulative ASF/SSF risk for varying preoperative diagnosis and rotator cuff status. METHODS: Patients consecutively receiving RSA between January 2013 and June 2019 from 15 institutions comprising 24 members of the American Shoulder and Elbow Surgeons (ASES) with primary, preoperative diagnoses of GHOA, CTA and MCT were included for study. Inclusion criteria, definitions, and inclusion of patient factors in a multivariate model to predict cumulative risk of ASF/SSF were determined through an iterative Delphi process. The CTA and MCT groups were combined for analysis. Consensus was defined as greater than 75% agreement amongst contributors. Only ASF/SSF confirmed by clinical and radiographic correlation were included for analysis. RESULTS: Our study cohort included 4764 patients with preoperative diagnoses of GHOA, CTA, or MCT with minimum follow-up of 3 months (range: 3-84). The incidence of cumulative stress fracture was 4.1% (n = 196). The incidence of stress fracture in the GHOA cohort was 2.1% (n = 34/1637) compared to 5.2% (n = 162/3127) (P < .001) in the CTA/MCT cohort. Presence of inflammatory arthritis (odds ratio [OR] 2.90, 95% confidence interval [CI] 1.08-7.78; P = .035) was the sole predictive factor of stress fractures in GHOA, compared with inflammatory arthritis (OR 1.86, 95% CI 1.19-2.89; P = .016), female sex (OR 1.81, 95% CI 1.20-2.72; P = .007), and osteoporosis (OR 1.56, 95% CI 1.02-2.37; P = .003) in the CTA/MCT cohort. CONCLUSION: Preoperative diagnosis of GHOA has a different risk profile for developing stress fractures after RSA than patients with CTA/MCT. Though rotator cuff integrity is likely protective against ASF/SSF, approximately 1/46 patients receiving RSA with primary GHOA will have this complication, primarily influenced by a history of inflammatory arthritis. Understanding risk profiles of patients undergoing RSA by varying diagnosis is important in counseling, expectation management, and treatment by surgeons.


Asunto(s)
Artritis , Artroplastía de Reemplazo de Hombro , Fracturas por Estrés , Lesiones del Manguito de los Rotadores , Articulación del Hombro , Femenino , Humanos , Artritis/cirugía , Artroplastía de Reemplazo de Hombro/efectos adversos , Fracturas por Estrés/diagnóstico por imagen , Fracturas por Estrés/etiología , Rango del Movimiento Articular , Estudios Retrospectivos , Factores de Riesgo , Lesiones del Manguito de los Rotadores/complicaciones , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Lesiones del Manguito de los Rotadores/cirugía , Escápula/diagnóstico por imagen , Escápula/cirugía , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía , Resultado del Tratamiento , Masculino
4.
PLoS One ; 17(5): e0267794, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35522660

RESUMEN

BACKGROUND: Heart failure (HF) is a serious health condition, associated with high health care costs, and poor outcomes. Patient empowerment and self-care are a key component of successful HF management. The emergence of telehealth may enable providers to remotely monitor patients' statuses, support adherence to medical guidelines, improve patient wellbeing, and promote daily awareness of overall patients' health. OBJECTIVE: To assess the feasibility of a voice activated technology for monitoring of HF patients, and its impact on HF clinical outcomes and health care utilization. METHODS: We conducted a randomized clinical trial; ambulatory HF patients were randomized to voice activated technology or standard of care (SOC) for 90 days. The system developed for this study monitored patient symptoms using a daily survey and alerted healthcare providers of pre-determined reported symptoms of worsening HF. We used summary statistics and descriptive visualizations to study the alerts generated by the technology and to healthcare utilization outcomes. RESULTS: The average age of patients was 54 years, the majority were Black and 45% were women. Almost all participants had an annual income below $50,000. Baseline characteristics were not statistically significantly different between the two arms. The technical infrastructure was successfully set up and two thirds of the invited study participants interacted with the technology. Patients reported favorable perception and high comfort level with the use of voice activated technology. The responses from the participants varied widely and higher perceived symptom burden was not associated with hospitalization on qualitative assessment of the data visualization plot. Among patients randomized to the voice activated technology arm, there was one HF emergency department (ED) visit and 2 HF hospitalizations; there were no events in the SOC arm. CONCLUSIONS: This study demonstrates the feasibility of remote symptom monitoring of HF patients using voice activated technology. The varying HF severity and the wide range of patient responses to the technology indicate that personalized technological approaches are needed to capture the full benefit of the technology. The differences in health care utilization between the two arms call for further study into the impact of remote monitoring on health care utilization and patients' wellbeing.


Asunto(s)
Insuficiencia Cardíaca , Telemedicina , Estudios de Factibilidad , Femenino , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Tecnología
5.
J Virol ; 82(11): 5381-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18353959

RESUMEN

Scaffolding proteins of spherical prokaryotic and eukaryotic viruses have critical roles in capsid assembly. The primary scaffolding components of cytomegalovirus, called the assembly protein precursor (pAP, pUL80.5) and the maturational protease precursor (pPR, pUL80a), contain two nuclear localization sequences (NLS1 and NLS2), at least one of which is required in coexpression experiments to translocate the major capsid protein (MCP, pUL85) into the nucleus. In the work reported here, we have mutated NLS1 and NLS2, individually or together, in human cytomegalovirus (HCMV, strain AD169) bacmid-derived viruses to test their effects on virus replication. Consistent with results from earlier transfection/coexpression experiments, both single-mutant bacmids gave rise to infectious virus but the double mutant did not. In comparisons with the wild-type virus, both mutants showed slower cell-to-cell spread; decreased yields of infectious virus (3-fold lower for NLS1(-) and 140-fold lower for NLS2(-)); reduced efficiency of pAP, pPR, and MCP nuclear translocation (sixfold lower for NLS1(-) and eightfold lower for NLS2(-)); increased amounts of a 120-kDa MCP fragment; and reduced numbers of intranuclear capsids. All effects were more severe for the NLS2(-) mutant than the NLS1(-) mutant, and a distinguishing feature of cells infected with the NLS2(-) mutant was the accumulation of large, UL80 protein-containing structures within the nucleus. We conclude that these NLS assist in the nuclear translocation of MCP during HCMV replication and that NLS2, which is unique to the betaherpesvirus UL80 homologs, may have additional involvements during replication.


Asunto(s)
Proteínas de la Cápside/metabolismo , Citomegalovirus/fisiología , Endopeptidasas/metabolismo , Proteínas Virales/metabolismo , Replicación Viral , Transporte Activo de Núcleo Celular , Proteínas de la Cápside/genética , Proteínas de la Cápside/ultraestructura , Células Cultivadas , Citomegalovirus/ultraestructura , Citosol/metabolismo , Endopeptidasas/genética , Genes Reporteros/genética , Humanos , Microscopía Electrónica de Transmisión , Mutación/genética , Señales de Localización Nuclear , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Proteínas Virales/genética
6.
J Virol ; 81(2): 620-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17079329

RESUMEN

Assembly of many spherical virus capsids is guided by an internal scaffolding protein or group of proteins that are often cleaved and eliminated in connection with maturation and incorporation of the genome. In cytomegalovirus there are at least two proteins that contribute to this scaffolding function; one is the maturational protease precursor (pUL80a), and the other is the assembly protein precursor (pUL80.5) encoded by a shorter genetic element within UL80a. Yeast GAL4 two-hybrid assays established that both proteins contain a carboxyl-conserved domain that is required for their interaction with the major capsid protein (pUL86) and an amino-conserved domain (ACD) that is required for their self-interaction and for their interaction with each other. In the work reported here, we demonstrate that when the ACD is deleted (deltaACD) or disrupted by a point mutation (L47A), the bacterially expressed mutant protein sediments as a monomer during rate-velocity centrifugation, whereas the wild-type protein sediments mainly as oligomers. We also show that the L47A mutation reduces the production of infectious virus by at least 90%, results in the formation of irregular nuclear capsids, gives rise to tube-like structures in the nucleus that resemble the capsid core in cross-section and contain UL80 proteins, slows nuclear translocation of the major capsid protein, and may slow cleavage by the maturational protease. We provide physical corroboration that mutating the ACD disrupts self-interaction of the UL80 proteins and biological support for the proposal that the ACD has a critical role in capsid assembly and production of infectious virus.


Asunto(s)
Cápside/metabolismo , Citomegalovirus/metabolismo , Endopeptidasas/química , Regulación Viral de la Expresión Génica , Proteínas Virales/química , Ensamble de Virus , Células Cultivadas , Citomegalovirus/genética , Citomegalovirus/patogenicidad , Endopeptidasas/genética , Endopeptidasas/metabolismo , Fibroblastos/virología , Humanos , Microscopía Fluorescente , Mutación Puntual , Técnicas del Sistema de Dos Híbridos , Proteínas Virales/genética , Proteínas Virales/metabolismo
7.
J Virol ; 80(12): 6003-12, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16731939

RESUMEN

We show here that the high-molecular-weight protein (HMWP or pUL48; 253 kDa) of human cytomegalovirus (HCMV) is a functionally competent deubiquitinating protease (DUB). By using a suicide substrate probe specific for ubiquitin-binding cysteine proteases (DUB probe) to screen lysates of HCMV-infected cells, we found just one infected-cell-specific DUB. Characteristics of this protein, including its large size, expression at late times of infection, presence in extracellular virus particles, and reactivity with an antiserum to the HMWP, identified it as the HMWP. This was confirmed by constructing mutant viruses with substitutions in two of the putative active-site residues, Cys24Ile and His162Ala. HMWP with these mutations either failed to bind the DUB probe (C24I) or had significantly reduced reactivity with it (H162A). More compellingly, the deubiquitinating activity detected in wild-type virus particles was completely abolished in both the C24I and H162A mutants, thereby directly linking HMWP with deubiquitinating enzyme activity. Mutations in these active-site residues were not lethal to virus replication but slowed production of infectious virus relative to wild type and mutations of other conserved residues. Initial studies, by electron microscopy, of cells infected with the mutants revealed no obvious differences at late times of replication in the general appearance of the cells or in the distribution, relative numbers, or appearance of virus particles in the cytoplasm or nucleus.


Asunto(s)
Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/fisiología , Citomegalovirus/enzimología , Proteínas Virales/fisiología , Sitios de Unión/genética , Células Cultivadas , Cisteína , Fibroblastos/virología , Histidina , Humanos , Mutación Missense , Proteínas Virales/genética , Virión , Replicación Viral/genética
8.
J Virol ; 79(20): 12961-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16188998

RESUMEN

The cytomegalovirus (CMV) maturational protease, assemblin, contains an "internal" (I) cleavage site absent from its homologs in other herpesviruses. Blocking this site for cleavage did not prevent replication of the resulting I(-) mutant virus. However, cells infected with the I(-) virus showed increased amounts of a fragment produced by cleavage at the nearby "cryptic" (C) site, suggesting that its replication may bypass the I-site block by using the C site as an alternate cleavage pathway. To test this and further examine the biological importance of these cleavages, we constructed two additional virus mutants-one blocked for C-site cleavage and another blocked for both I- and C-site cleavage. Infectivity comparisons with the parental wild-type virus showed that the I(-) mutant was the least affected for virus production, whereas infectivity of the C(-) mutant was reduced by approximately 40% and when both sites were blocked virus infectivity was reduced by nearly 90%, providing the first evidence that these cleavages have biological significance. We also present and discuss evidence suggesting that I-site cleavage destabilizes assemblin and its fragments, whereas C-site cleavage does not.


Asunto(s)
Citomegalovirus/fisiología , Serina Endopeptidasas/fisiología , Línea Celular , Citomegalovirus/enzimología , Humanos , Serina Endopeptidasas/metabolismo , Replicación Viral
9.
J Biol Chem ; 280(39): 33206-12, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-16036911

RESUMEN

Chemical rescue is an established approach that offers a directed strategy for designing mutant enzymes in which activity can be restored by supplying an appropriate exogenous compound. This method has been used successfully to study a broad range of enzymes in vitro, but its application to living systems has received less attention. We have investigated the feasibility of using chemical rescue to make a conditional-lethal mutant of the cytomegalovirus (CMV) maturational protease. The 28-kDa CMV serine protease, assemblin, has a Ser-His-His catalytic triad and an internal (I) cleavage site near its midpoint. We found that imidazole can restore I-site cleavage to mutants inactivated by replacing the critical active site His with Ala or with Gly, which rescued better. Comparable rescue was observed for counterpart mutants of the human and simian CMV assemblin homologs and occurred in both living cells and in vitro. Cleavage was established to be at the correct site by amino acid sequencing and proceeded at approximately 11%/h in bacteria and approximately 30%/h in vitro. The same mutations were unresponsive to chemical rescue in the context of the assemblin precursor, pUL80a. This catalytic difference distinguishes the two forms of the CMV protease.


Asunto(s)
Citomegalovirus/enzimología , Precursores Enzimáticos/metabolismo , Serina Endopeptidasas/metabolismo , Alanina/metabolismo , Sustitución de Aminoácidos , Línea Celular , Línea Celular Transformada , Transformación Celular Viral , Clonación Molecular , Inhibidores Enzimáticos/farmacología , Precursores Enzimáticos/genética , Estudios de Factibilidad , Glicina/metabolismo , Humanos , Imidazoles/farmacología , Cinética , Mutagénesis Sitio-Dirigida , Plásmidos , Análisis de Secuencia de Proteína , Serina Endopeptidasas/química , Serina Endopeptidasas/genética
10.
J Virol ; 78(24): 13501-11, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15564461

RESUMEN

Capsid assembly among the herpes-group viruses is coordinated by two related scaffolding proteins. In cytomegalovirus (CMV), the main scaffolding constituent is called the assembly protein precursor (pAP). Like its homologs in other herpesviruses, pAP is modified by proteolytic cleavage and phosphorylation. Cleavage is essential for capsid maturation and production of infectious virus, but the role of phosphorylation is undetermined. As a first step in evaluating the significance of this modification, we have identified the specific sites of phosphorylation in the simian CMV pAP. Two were established previously to be adjacent serines (Ser156 and Ser157) in a casein kinase II consensus sequence. The remaining two, identified here as Thr231 and Ser235, are within consensus sequences for glycogen synthase kinase 3 (GSK-3) and mitogen-activated protein kinase, respectively. Consistent with Thr231 being a GSK-3 substrate, its phosphorylation required a downstream "priming" phosphate (i.e., Ser235) and was reduced by a GSK-3-specific inhibitor. Phosphorylation of Ser235 converts pAP to an electrophoretically slower-mobility isoform, pAP*; subsequent phosphorylation of pAP* at Thr231 converts pAP* to a still-slower isoform, pAP**. The mobility shift to pAP* was mimicked by substituting an acidic amino acid for either Thr231 or Ser235, but the shift to pAP** required that both positions be phosphorylated. Glu did not substitute for pSer235 in promoting phosphorylation of Thr231. We suggest that phosphorylation of Thr231 and Ser235 causes charge-driven conformational changes in pAP, and we demonstrate that preventing these modifications alters interactions of pAP with itself and with major capsid protein, suggesting a functional significance.


Asunto(s)
Proteínas de la Cápside/metabolismo , Citomegalovirus/metabolismo , Glucógeno Sintasa Quinasa 3/química , Precursores de Proteínas/metabolismo , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Espectrometría de Masas , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mapeo Peptídico , Fosforilación , Precursores de Proteínas/química , Precursores de Proteínas/genética , Proteínas Virales/química , Proteínas Virales/genética
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