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2.
BMC Emerg Med ; 23(1): 141, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38030981

RESUMEN

BACKGROUND AND IMPORTANCE: Use of video review in medicine is established in contexts such as surgery. Although not widely used in the emergency department (ED), some centres use it to evaluate non-technical skills (NTS) to support teaching and quality improvement. OBJECTIVE: There is no consensus on assessment of NTS using video review in the ED and the purpose of this review was to identify tools used in this context. DESIGN, SETTING AND PARTICIPANTS: Studies were identified using Embase, Medline, CINAHL and Google Scholar. Inclusion criterion for the review was NTS of resuscitation teams working within the ED were assessed using video review. A systematic search method was used, and results were synthesised after search criteria was checked by two independent reviewers. Authors settled on the same 9 studies eligible for inclusion. OUTCOME MEASURES AND ANALYSIS: Reliability and validity of tools identified for use in this context. Due to the heterogeneity of studies, no meta-analysis occurred. MAIN RESULTS: There are 9 studies included in the review. The review was registered with PROSPERO (Ref No: CRD42022306129). Four unique tools were identified - 6 studies used T-NOTECHS, 1 used TTCA-24, 1 used CALM and 1 used the Communication tool. T-NOTECHS is validated in the literature for use in this context. CONCLUSION: T-NOTECHS is the tool of choice for assessing ED teams in this context.


Asunto(s)
Competencia Clínica , Grupo de Atención al Paciente , Humanos , Reproducibilidad de los Resultados , Servicio de Urgencia en Hospital , Comunicación
3.
Cardiovasc Drugs Ther ; 37(5): 1021-1026, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-35488973

RESUMEN

PURPOSE: Previous work suggests that Dihydroorotate dehydrogenase (DHODH) inhibition via teriflunomide (TERI) may provide protection in multiple disease models. To date, little is known about the effect of TERI on the heart. This study was performed to assess the potential effects of TERI on cardiac ischemia reperfusion injury. METHODS: Male and female rat hearts were subjected to global ischemia (25 min) and reperfusion (120 min) on a Langendorff apparatus. Hearts were given either DMSO (VEH) or teriflunomide (TERI) for 5 min prior to induction of ischemia and during the reperfusion period. Left ventricular pressure, ECG, coronary flow, and infarct size were determined using established methods. Mitochondrial respiration was assessed via respirometry. RESULTS: Perfusion of hearts with TERI led to no acute effects in any values measured across 500 pM-50 nM doses. However, following ischemia-reperfusion injury, we found that 50 nM TERI-treated hearts had an increase in myocardial infarction (p < 0.001). In 50 nM TERI-treated hearts, we also observed a marked increase in the severity of contracture (p < 0.001) at an earlier time-point (p = 0.004), as well as reductions in coronary flow (p = 0.037), left ventricular pressure development (p = 0.025), and the rate-pressure product (p = 0.008). No differences in mitochondrial respiration were observed with 50 nM TERI treatment (p = 0.24-0.87). CONCLUSION: This study suggests that treatment with TERI leads to more negative outcomes following cardiac ischemia reperfusion, and administration of TERI to at-risk populations should receive special considerations.


Asunto(s)
Infarto del Miocardio , Isquemia Miocárdica , Daño por Reperfusión , Ratas , Animales , Masculino , Femenino , Corazón , Miocardio
4.
Prof Sch Couns ; 26(1b): 2156759X221105557, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36118911

RESUMEN

The COVID-19 pandemic and the shift to online learning exacerbated the mental health needs of children and adolescents, especially among minoritized students who were disproportionately impacted by the virus. Although the pandemic has increased the demand for counseling, research finds that school counselors are often hindered by organizational constraints. Using organizational role theory, this study examined school counselors' perceptions of their role delivering mental health supports during the pandemic. Findings indicate that school counselors reported an increased need for counseling, but faced multiple barriers to supporting students, leaving those who most needed the support particularly vulnerable.

5.
Child Obes ; 17(8): 516-524, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34227849

RESUMEN

Background: Partnerships with community programs have been used to improve access to obesity care and address clinical barriers to childhood obesity management; however, little is known about the program referral process. The objective of this study was to identify factors that affect the referral from clinics to community-based programs. Methods: Active Recreation through Community-Healthcare Engagement Study (ARCHES) is a mixed-method, implementation study designed to test the feasibility of establishing clinic-community partnerships to treat childhood obesity. We collected clinical referral and program attendance data from the six ARCHES clinic-community partnerships and conducted semistructured interviews (n = 19) with key stakeholders. Logistic regression models were used to identify referral characteristics associated with ever attending a community program. We used deductive thematic analysis to examine contextual factors affecting the clinical referral and subsequent attendance at the community programs. Results: Patients referred from individual providers [odds ratio (OR): 3.20, 95% confidence interval (CI): 1.08-9.48], specialty clinics (OR: 2.73, 95% CI: 1.48-5.05), and community wellness clinics (OR: 3.42, 95% CI: 1.05-11.13), had greater odds of ever attending the programs compared with patients from primary care clinics. Patients referred to cohort-based programs compared with open enrollment programs had greater odds of ever attending the programs. Stakeholders emphasized the value of communication within the partnership and with patients in clinical settings. Effective provider communication with patients involved engaging and program endorsing conversations to explain the value of the program. Conclusions: We identified factors that may improve the referral process in clinic-community partnerships to provide resources to primary care providers looking to address childhood obesity. Clinical Trial Registration number: NCT03246763.


Asunto(s)
Obesidad Infantil , Niño , Estudios de Cohortes , Servicios de Salud Comunitaria , Personal de Salud , Humanos , Obesidad Infantil/epidemiología , Obesidad Infantil/prevención & control , Derivación y Consulta
6.
J Adolesc Health ; 69(2): 263-271, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33958267

RESUMEN

PURPOSE: Physical activity is strongly associated with health benefits in youth, although wide disparities in physical activity persist across sex, race/ethnicity, and income. Active transportation is an important source of youth physical activity. We aimed to describe active transportation patterns for United States adolescents and young adults ages 12-25 years across sociodemographic and weight status characteristics. METHODS: Cross-sectional secondary data analyses were based on self-reported transportation-related physical activity using the National Health and Nutrition Examination Survey, 2007-2016. RESULTS: Of the sample (n = 8,680; population represented, N = 57,768,628), 4,300 (49.5%) were adolescents (12-17 y), and 4,380 (50.4%) were young adults (18-25 y). Male adolescents were more likely to participate in any (risk ratio [RR] = 1.3; 95% confidence interval [CI], 1.16-1.40) and daily (RR = 1.3; 95% CI, 1.06-1.63) active transportation than females. Black (RR = 1.1; 95% CI, 1.01-1.31) and Hispanic (RR = 1.2; 95% CI, 1.05-1.31) adolescents were more likely to engage in any active transportation than whites. Young adult males were more likely to participate in any (RR = 1.3; 95% CI, 1.20-1.50) and daily (RR = 1.3; 95% CI, 1.08-1.55) active transportation than females. Young adults with a lower family income, and both adolescents and young adults with a lower household education, were more likely to engage in any and daily active transportation. We also observed an inverse relationship between weight class and active transportation participation. CONCLUSION: Active transportation was higher in males, minority, and lower income youth. Our study findings provide evidence for physical activity interventions, suggesting active transportation is a feasible target for low-income and minority youth to reduce physical activity disparities and support optimal health.


Asunto(s)
Ejercicio Físico , Transportes , Adolescente , Adulto , Niño , Estudios Transversales , Femenino , Humanos , Renta , Masculino , Encuestas Nutricionales , Estados Unidos , Adulto Joven
7.
J Adolesc Health ; 68(4): 801-807, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33158686

RESUMEN

PURPOSE: We sought to evaluate if internalizing symptoms (i.e., anxiety and depression) and/or externalizing symptoms (i.e., impulsivity, sensation seeking, and substance use) were risk factors for the onset of 30-day e-cigarette use and escalation in the number of days used across the following 30 months among adolescents. METHODS: Adolescents (N = 1,808) from public high schools outside Philadelphia, PA, completed in-classroom surveys at wave 1 (fall 2016, beginning of ninth grade) and at 6-month intervals for the following 30 months (spring 2019, end of 11th grade). RESULTS: A two-part latent growth curve model of e-cigarette use revealed significant positive associations between externalizing factors, past 30-day e-cigarette use, and the number of days of e-cigarette use only at wave 1 (p values <.05). Cigarette smoking was associated with a slowing in the rate of onset of 30-day e-cigarette use across the 30-month follow-up (ß = -.24, z = -2.41, p = .02). Depression was associated with an increased rate of escalation in the number of days of e-cigarette use across the following 30 months (ß = .01, z = 2.52, p = .01), whereas anxiety was associated with a decreased rate (ß = -.72, z = -2.36, p = .02). CONCLUSIONS: The findings highlight two groups of adolescents at risk for e-cigarette use: adolescents whose e-cigarette use reflects a higher-risk profile with early e-cigarette onset, and adolescents who have a lower-risk profile, at least initially, with later e-cigarette use onset. The timing and content of prevention efforts should be tailored to each group.


Asunto(s)
Conducta del Adolescente , Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Vapeo , Adolescente , Humanos , Philadelphia
8.
Front Neurosci ; 14: 752, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32792899

RESUMEN

Multiple studies have demonstrated that musicians have enhanced auditory processing abilities compared to non-musicians. In these studies, musicians are usually defined as having received some sort of formal music training. One issue with this definition is that there are many musicians who are self-taught. The goal of the current study was to determine if self-taught musicians exhibit different auditory enhancements as their formally trained counterparts. Three groups of participants were recruited: formally trained musicians, who received formal music training through the conservatory or private lessons; self-taught musicians, who learned to play music through informal methods, such as with books, videos, or by ear; non-musicians, who had little or no music experience. Auditory processing abilities were assessed using a speech-in-noise task, a passive pitch oddball task done while recording electrical brain activity, and a melodic tonal violation task, done both actively and passively while recording electrical brain activity. For the melodic tonal violation task, formally trained musicians were better at detecting a tonal violation compared to self-taught musicians, who were in turn better than non-musicians. The P600 evoked by a tonal violation was enhanced in formally trained musicians compared to non-musicians. The P600 evoked by an out-of-key note did not differ between formally trained and self-taught musicians, while the P600 evoked by an out-of-tune note was smaller in self-taught musicians compared to formally trained musicians. No differences were observed between the groups for the other tasks. This pattern of results suggests that music training format impacts auditory processing abilities in musical tasks; however, it is possible that these differences arose due to pre-existing factors and not due to the training itself.

9.
JAMA Netw Open ; 2(12): e1917001, 2019 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-31808925

RESUMEN

Importance: Almost two-thirds of adolescents who smoke blunts also report using cigars. Although adolescent co-use of blunts and cigars is prevalent, whether adolescent blunt use is associated with progression to current cigar use (past 30-day use) and increased frequency of use is unknown. Objective: To determine whether adolescent use of blunts is associated with progression to cigar use (past 30-day use) and increased number of days used (in the past 30 days) across the subsequent 24 months compared with adolescents who have never used blunts. Design, Setting, and Participants: In this prospective cohort study of adolescents from 4 public high schools outside of Philadelphia, Pennsylvania, in-classroom surveys were administered at baseline (fall 2016, beginning of 9th grade) and at 6-month intervals for the following 24 months (fall 2018, beginning of 11th grade). Data analyses were conducted in September and October 2019. Exposures: Self-report of lifetime (ever) blunt use at baseline (age 14 years). Main Outcomes and Measures: Progression to current cigar use (use in the past 30 days) and escalation in the frequency of use (number of days used in the past 30 days) across the subsequent 24 months. Results: Of 1825 participants, 907 (49.7%) were female, 1330 (72.9%) were white, and 376 (20.6%) were Hispanic; the mean (SD) age at baseline was 14.38 (0.55) years. In all, 257 participants (14.0%) reported ever blunt use. Mixed-effects models revealed that ever blunt use at baseline vs never blunt use was associated with progression to current cigar use (past 30 days use: odds ratio, 22.66; 95% CI, 11.34-45.27) but not escalation in the number of days used across the following 24 months (ß = 0.13; 95% CI, -0.17 to 0.43). Conclusions and Relevance: These findings highlight the risk that blunt use may pose for subsequent cigar use among adolescents. Policies and public health campaigns addressing marijuana as well as cigars will be important to reduce adolescent blunt use and cigar use.


Asunto(s)
Fumar Marihuana/epidemiología , Estudiantes/estadística & datos numéricos , Productos de Tabaco/estadística & datos numéricos , Adolescente , Femenino , Humanos , Masculino , Oportunidad Relativa , Philadelphia/epidemiología , Estudios Prospectivos , Autoinforme
10.
Drug Alcohol Depend ; 202: 149-155, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31351341

RESUMEN

OBJECTIVE: E-cigarettes are the most prevalent tobacco product used by adolescents. We sought to determine whether the presence of flavoring and/or the presence of nicotine at the first e-cigarette exposure predicted progression to current e-cigarette use (use in past 30 days) as well as escalation in use (number of days in the past 30 days) among adolescents. METHODS: Adolescents from public high schools outside of Philadelphia, PA completed in-classroom surveys at baseline (9th grade) and at 6-month intervals for the following 18 months (fall 2018, beginning of 11th grade). Adolescents who reported ever having used e-cigarettes at baseline (N = 354) comprised the analytical sample. RESULTS: We employed a two-part Latent Growth Curve Model including flavor, nicotine, and other covariates. Initial use of a flavored (vs unflavored) e-cigarette was associated with progression to current e-cigarette use (ß = 0.54, z = 2.09, p = 0.04) and escalation in the number of days of e-cigarette use (ß = 0.35, z = 2.58, p = 0.01) across the following 18 months. Initial use of an e-cigarette with nicotine (vs without nicotine) was associated with a greater number of days of e-cigarette use at baseline (ß = 0.49, z = 2.16, p = 0.03). CONCLUSIONS: The findings underscore the risk that flavoring and nicotine pose for progression beyond initial e-cigarette use. Regulations addressing flavoring and nicotine in e-cigarettes have the potential to reduce the number of adolescents who become current as well as frequent e-cigarette users.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Aromatizantes/análisis , Nicotina/análisis , Estudiantes/psicología , Vapeo/psicología , Adolescente , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Philadelphia/epidemiología , Instituciones Académicas , Encuestas y Cuestionarios , Gusto , Vapeo/epidemiología
12.
Expert Opin Biol Ther ; 16(12): 1445-1453, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27666115

RESUMEN

INTRODUCTION: Loss of exclusivity for biological therapeutics opens the door for biosimilar development. Biosimilars must demonstrate structural, functional, and clinical similarity with a currently approved biological originator product. A therapeutic alternative for biologic-naive patients, a single switch from an originator to biosimilar has also been studied in clinically stable patients; further, switching therapy multiple times (alternating) between an originator and a biosimilar has been investigated. Because biosimilars are not identical to originators and no robust clinical data have convincingly demonstrated that switching or alternating therapy of stable patients is safe and efficacious, there is an imperative need to understand the characteristics of well-designed clinical trials to support these practices. Areas covered: Clinical trials of biosimilars are reviewed, with an emphasis on trial designs that incorporate therapy switching, including the NOR-SWITCH study as an example. Expert opinion: As currently designed, biosimilar clinical trials provide insufficient information to support switching or alternating between originator products and their biosimilars. Lack of regulatory guidance contributes to this void. More robust data are required to inform the safety and efficacy of switching or alternating therapies, particularly regarding immunogenicity risks. Studies that also include alternations of therapy are needed to address these knowledge gaps.


Asunto(s)
Factores Biológicos/administración & dosificación , Biosimilares Farmacéuticos/administración & dosificación , Ensayos Clínicos como Asunto/métodos , Sustitución de Medicamentos/métodos , Factores Biológicos/química , Biosimilares Farmacéuticos/química , Humanos , Proyectos de Investigación
13.
Adv Ther ; 32(3): 270-83, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25772256

RESUMEN

INTRODUCTION: The purpose of the present study was to investigate the traceability of adverse events (AEs) for branded and generic drugs with identical nonproprietary names and to consider potential implications for the traceability of AEs for branded and biosimilar biologics. METHODS: Adverse event reports in the Food and Drug Administration AE Reporting System (FAERS) were compared with those in a commercial insurance claims database (Truven Health MarketScan(®)) for 2 drugs (levetiracetam and enoxaparin sodium) with manufacturing or prescribing considerations potentially analogous to those of some biosimilars. Monthly rates of branded- and generic-attributed AEs were estimated pre- and post-generic entry. Post-entry branded-to-generic AE relative rate ratios were calculated. RESULTS: In FAERS, monthly AE rate ratios during the post-generic period showed a pattern in which AE rates for the branded products were greater than for the generic products. Differences in rates of brand- and generic-attributed AEs were statistically significant for both study drugs; the AE rate for the branded products peaked at approximately 10 times that of the generic levetiracetam products and approximately 4 times that of the generic enoxaparin sodium products. In contrast, monthly ratios for the MarketScan data were relatively constant over time. CONCLUSION: Use of the same nonproprietary name for generic and branded products may contribute to poor traceability of AEs reported in the FAERS database due to the significant misattribution of AEs to branded products (when those AEs were in fact associated with patient use of generic products). To ensure accurate and robust safety surveillance and traceability for biosimilar products in the United States, improved product identification mechanisms, such as related but distinguishable nonproprietary names for biosimilars and reference biologics, should be considered.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos/organización & administración , Biosimilares Farmacéuticos/efectos adversos , Medicamentos Genéricos/efectos adversos , Terminología como Asunto , Adulto , Sistemas de Registro de Reacción Adversa a Medicamentos/normas , Bases de Datos Factuales , Humanos , Revisión de Utilización de Seguros , Estados Unidos , United States Food and Drug Administration
14.
J Genet Couns ; 20(2): 129-35, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20878216

RESUMEN

The University of British Columbia Hospital Clinic for Alzheimer Disease and Related Disorders (UBCH-CARD) invests significant effort to obtain medical records for the confirmation of patient-reported family histories of dementia. The effectiveness of requesting these records was assessed through a review of the 275 requests made by UBCH-CARD genetic counselors during the 24-month period of January 1, 2005-December 31, 2006. The results were categorized according to outcome. Useful medical records were obtained from 92 (33.5%) requests: 77 (28%) records supported, and 15 (5.5%) records did not support, the patient-reported information. An additional 20 (7.5%) requests yielded only vague information. When verification was possible, patient-reported family histories of Alzheimer disease, dementia, or memory loss were accurate in 84% of cases. During the study period, almost 500 h of genetic counselor work time was spent obtaining, reviewing, and following-up on records received. Changes made to UBCH-CARD procedure in response to these findings are discussed.


Asunto(s)
Enfermedad de Alzheimer/terapia , Asesoramiento Genético , Predisposición Genética a la Enfermedad , Anamnesis , Registros Médicos , Enfermedad de Alzheimer/genética , Humanos
15.
Am J Health Syst Pharm ; 65(22): 2144-9, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18997144

RESUMEN

PURPOSE: Nontraditional work schedules for pharmacists at three institutions are described. SUMMARY: The demand for pharmacists and health care in general continues to increase, yet significant material changes are occurring in the pharmacy work force. These changing demographics, coupled with historical vacancy rates and turnover trends for pharmacy staff, require an increased emphasis on workplace changes that can improve staff recruitment and retention. At William S. Middleton Memorial Veterans Affairs Hospital in Madison, Wisconsin, creative pharmacist work schedules and roles are now mainstays to the recruitment and retention of staff. The major challenge that such scheduling presents is the 8 hours needed to prepare a six-week schedule. Baylor Medical Center at Grapevine in Dallas, Texas, has a total of 45 pharmacy employees, and slightly less than half of the 24.5 full-time-equivalent staff work full-time, with most preferring to work one, two, or three days per week. As long as the coverage needs of the facility are met, Envision Telepharmacy in Alpine, Texas, allows almost any scheduling arrangement preferred by individual pharmacists or the pharmacist group covering the facility. Staffing involves a great variety of shift lengths and intervals, with shifts ranging from 2 to 10 hours. Pharmacy leaders must be increasingly aware of opportunities to provide staff with unique scheduling and operational enhancements that can provide for a better work-life balance. CONCLUSION: Compressed workweeks, job-sharing, and team scheduling were the most common types of alternative work schedules implemented at three different institutions.


Asunto(s)
Admisión y Programación de Personal/estadística & datos numéricos , Farmacéuticos , Servicio de Farmacia en Hospital/estadística & datos numéricos , Telemedicina/estadística & datos numéricos , Carga de Trabajo/estadística & datos numéricos , Adulto , Femenino , Hospitales de Veteranos , Humanos , Masculino , Persona de Mediana Edad , Admisión y Programación de Personal/organización & administración , Reorganización del Personal , Servicio de Farmacia en Hospital/organización & administración , Estados Unidos
16.
Langmuir ; 23(5): 2289-92, 2007 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-17274638

RESUMEN

Atomic force microscopy was used to "fish" for binding reactions between a fibronectin-coated probe (i.e., substrate simulating an implant device) and each of 15 different isolates of Staphylococcus aureus obtained from either patients with an infected cardiac prosthesis (invasive group) or healthy human subjects (control group). There is a strong distinction (p = 0.01) in the binding-force signature observed for the invasive versus control populations. This observation suggests that a microorganism's "force taxonomy" may provide a fundamental and practical indicator of the pathogen-related risk that infections pose to patients with implanted medical devices.


Asunto(s)
Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/diagnóstico , Staphylococcus aureus/metabolismo , Biopelículas , Fibronectinas/química , Humanos , Microscopía de Fuerza Atómica , Distribución de Poisson , Prótesis e Implantes , Reproducibilidad de los Resultados , Infecciones Estafilocócicas/inmunología
17.
Gen Comp Endocrinol ; 148(2): 125-31, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16413551

RESUMEN

An islet xenotransplantation model has been developed using tilapia (Oreochromis niloticus) as the donors. Studies using this model for the treatment of experimental type 1 diabetes in mice have produced promising results including the maintenance of long-term normoglycemia and mammalian-like glucose tolerance profiles in islet graft recipients. Islet encapsulation has also provided a promising method for the prevention of graft rejection, and strains of transgenic tilapia expressing a [desThrB30] human insulin molecule have been produced. In addition to studying islet transplantation for the treatment of type 1 diabetes, these studies have also produced insights into piscine glucose homeostasis. Studies demonstrating the glucose responsiveness of tilapia islets are described. In addition, work performed by our group and by others pertaining to presence and nature of piscine glucose transporters is reviewed. Finally, studies addressing some of the broader challenges of islet xenotransplantation are discussed with particular attention paid to the post-transplantation fate of the various islet cell populations and the proteins they produce.


Asunto(s)
Trasplante de Islotes Pancreáticos/fisiología , Tilapia/fisiología , Tilapia/cirugía , Trasplante Heterólogo/fisiología , Trasplante Heterólogo/veterinaria , Animales , Diabetes Mellitus Tipo 1/terapia , Sistema Endocrino/fisiología , Humanos
18.
Cryobiology ; 50(1): 17-20, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15710365

RESUMEN

PURPOSE: To reduce the time taken for thawing and removal of cryoprotectant from heart valves. METHODS: Three sets of experiments were carried out using porcine heart valves. The valves in all three experiments were first exposed to 10% (v/v) dimethyl sulphoxide (DMSO) by a 2-step protocol. Outcome was determined after the various experimental treatments by monitoring the outgrowth of cells from valve leaflet explants. Experiment 1-Dilution protocol. Valves exposed to 10% DMSO were subjected to 4-, 2- or 1-step dilution to remove the DMSO. Experiment 2-Warming rate. The rate of warming was increased by reducing the volume of cryoprotectant medium in which the valves were frozen. Valves were exposed to 10% DMSO, frozen in different volumes (100, 50, 25 or 0 ml) of cryoprotectant medium, and warmed in a 37 degrees C water bath. The DMSO was removed by 4-step dilution. Experiment 3-Standard vs. Modified protocol. Valves were either frozen in 100 ml 10% DMSO, thawed, and subjected to 4-step dilution (Standard) or frozen in 50 ml 10% DMSO, thawed, and the DMSO removed by single-step dilution (Modified). RESULTS: Neither the rate of warming nor the rate of dilution of DMSO had any influence on the subsequent outgrowth of valve leaflet fibroblasts. There were no differences in the outgrowth of cells from valve leaflets cryopreserved by the Standard or Modified protocols. CONCLUSION: The time taken for thawing and dilution of heart valves could be reduced from >20 min to <10 min without detriment to the viability of the leaflet fibroblasts. This should have a positive impact on valve replacement surgery as the thawing and dilution of valves are typically carried out while the patients are on cardiopulmonary bypass.


Asunto(s)
Criopreservación/métodos , Crioprotectores/farmacología , Prótesis Valvulares Cardíacas , Válvulas Cardíacas/efectos de los fármacos , Válvulas Cardíacas/patología , Animales , Proliferación Celular , Criopreservación/instrumentación , Crioprotectores/administración & dosificación , Técnicas de Cultivo , Dimetilsulfóxido/farmacología , Endotelio Vascular/citología , Fibroblastos/citología , Fibroblastos/metabolismo , Congelación , Técnicas de Cultivo de Órganos/métodos , Porcinos , Temperatura , Factores de Tiempo , Conservación de Tejido/métodos
19.
BMC Microbiol ; 3: 5, 2003 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-12697056

RESUMEN

BACKGROUND: Staphylococcus aureus infection of normal osteoblasts induces expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). RESULTS: Normal osteoblasts were incubated in the presence of purified bacterial products over a range of concentrations. Results demonstrate that purified surface structures and a selected superantigen present in the extracellular environment are not capable of inducing TRAIL expression by osteoblasts. Osteoblasts were co-cultured with S. aureus at various multiplicities of infection utilizing cell culture chamber inserts. Results of those experiments suggest that direct contact between bacteria and osteoblasts is necessary for optimal TRAIL induction. Finally, S. aureus infection of osteoblasts in the presence of anti-TRAIL antibody demonstrates that TRAIL mediates caspase-8 activation and apoptosis of infected cells. CONCLUSIONS: Collectively, these findings suggest a mechanism whereby S. aureus mediates bone destruction via induction of osteoblast apoptosis.


Asunto(s)
Apoptosis , Caspasas/metabolismo , Glicoproteínas de Membrana/biosíntesis , Osteoblastos/microbiología , Staphylococcus aureus/fisiología , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis , Caspasa 8 , Células Cultivadas , Activación Enzimática , Humanos , Ligandos , Glicoproteínas de Membrana/fisiología , Ratones , Osteoblastos/enzimología , Osteoblastos/metabolismo , Osteoblastos/patología , Staphylococcus aureus/química , Ligando Inductor de Apoptosis Relacionado con TNF , Factor de Necrosis Tumoral alfa/fisiología
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