Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Ann Intern Med ; 171(8): 555-567, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31590181

RESUMEN

Background: Whether health care provider burnout contributes to lower quality of patient care is unclear. Purpose: To estimate the overall relationship between burnout and quality of care and to evaluate whether published studies provide exaggerated estimates of this relationship. Data Sources: MEDLINE, PsycINFO, Health and Psychosocial Instruments (EBSCO), Mental Measurements Yearbook (EBSCO), EMBASE (Elsevier), and Web of Science (Clarivate Analytics), with no language restrictions, from inception through 28 May 2019. Study Selection: Peer-reviewed publications, in any language, quantifying health care provider burnout in relation to quality of patient care. Data Extraction: 2 reviewers independently selected studies, extracted measures of association of burnout and quality of care, and assessed potential bias by using the Ioannidis (excess significance) and Egger (small-study effect) tests. Data Synthesis: A total of 11 703 citations were identified, from which 123 publications with 142 study populations encompassing 241 553 health care providers were selected. Quality-of-care outcomes were grouped into 5 categories: best practices (n = 14), communication (n = 5), medical errors (n = 32), patient outcomes (n = 17), and quality and safety (n = 74). Relations between burnout and quality of care were highly heterogeneous (I2 = 93.4% to 98.8%). Of 114 unique burnout-quality combinations, 58 indicated burnout related to poor-quality care, 6 indicated burnout related to high-quality care, and 50 showed no significant effect. Excess significance was apparent (73% of studies observed vs. 62% predicted to have statistically significant results; P = 0.011). This indicator of potential bias was most prominent for the least-rigorous quality measures of best practices and quality and safety. Limitation: Studies were primarily observational; neither causality nor directionality could be determined. Conclusion: Burnout in health care professionals frequently is associated with poor-quality care in the published literature. The true effect size may be smaller than reported. Future studies should prespecify outcomes to reduce the risk for exaggerated effect size estimates. Primary Funding Source: Stanford Maternal and Child Health Research Institute.


Asunto(s)
Agotamiento Profesional/epidemiología , Calidad de la Atención de Salud , Agotamiento Profesional/psicología , Personal de Salud/psicología , Humanos , Calidad de la Atención de Salud/estadística & datos numéricos
2.
J Allergy Clin Immunol ; 140(5): 1339-1350, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28343701

RESUMEN

BACKGROUND: Newborns display distinct immune responses, leaving them vulnerable to infections and impairing immunization. Targeting newborn dendritic cells (DCs), which integrate vaccine signals into adaptive immune responses, might enable development of age-specific vaccine formulations to overcome suboptimal immunization. OBJECTIVE: Small-molecule imidazoquinoline Toll-like receptor (TLR) 8 agonists robustly activate newborn DCs but can result in reactogenicity when delivered in soluble form. We used rational engineering and age- and species-specific modeling to construct and characterize polymer nanocarriers encapsulating a TLR8 agonist, allowing direct intracellular release after selective uptake by DCs. METHODS: Chemically similar but morphologically distinct nanocarriers comprised of amphiphilic block copolymers were engineered for targeted uptake by murine DCs in vivo, and a range of TLR8 agonist-encapsulating polymersome formulations were then synthesized. Novel 96-well in vitro assays using neonatal human monocyte-derived DCs and humanized TLR8 mouse bone marrow-derived DCs enabled benchmarking of the TLR8 agonist-encapsulating polymersome formulations against conventional adjuvants and licensed vaccines, including live attenuated BCG vaccine. Immunogenicity of the TLR8 agonist adjuvanted antigen 85B (Ag85B)/peptide 25-loaded BCG-mimicking nanoparticle formulation was evaluated in vivo by using humanized TLR8 neonatal mice. RESULTS: Although alum-adjuvanted vaccines induced modest costimulatory molecule expression, limited TH-polarizing cytokine production, and significant cell death, BCG induced a robust adult-like maturation profile of neonatal DCs. Remarkably, TLR8 agonist polymersomes induced not only newborn DC maturation profiles similar to those induced by BCG but also stronger IL-12p70 production. On subcutaneous injection to neonatal mice, the TLR8 agonist-adjuvanted Ag85B peptide 25 formulation was comparable with BCG in inducing Ag85B-specific CD4+ T-cell numbers. CONCLUSION: TLR8 agonist-encapsulating polymersomes hold substantial potential for early-life immunization against intracellular pathogens. Overall, our study represents a novel approach for rational design of early-life vaccines.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Vacuna BCG/inmunología , Células Dendríticas/inmunología , Imidazoles/administración & dosificación , Monocitos/inmunología , Nanopartículas/administración & dosificación , Quinolinas/administración & dosificación , Inmunidad Adaptativa , Animales , Animales Recién Nacidos , Biomimética , Linfocitos T CD4-Positivos/inmunología , Células Cultivadas , Citocinas/metabolismo , Humanos , Imidazoles/química , Imidazoles/farmacología , Inmunidad Innata , Inmunomodulación , Recién Nacido , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Nanopartículas/química , Polímeros/química , Quinolinas/química , Quinolinas/farmacología , Receptor Toll-Like 8/agonistas , Vacunación
3.
Workplace Health Saf ; 68(12): 560-566, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32812844

RESUMEN

BACKGROUND: Nearly half of U.S. pediatricians have symptoms of burnout. This pilot study examined the feasibility of a 6-week yoga-based program (RISE) for neonatologists and obstetricians at Brigham and Women's Hospital and studied the effects on burnout, professional fulfillment, and psychological health. METHODS: Participants were recruited via email to participate either in both program and research study, or exclusively the program. RISE was delivered 1 hour/week during the workday for 6 consecutive weeks either in-person or remotely; 18 physicians participated, 12 completed post-program, and 11 completed 2-month follow-up. The questionnaires assessed burnout and measures of psychological health, professional fulfillment, work exhaustion, interpersonal disengagement/burnout (PFI), mindfulness (FFMQ), perceived stress (PSS), positive/negative affect (PANAS), resilience (RS), anxiety/depression/sleep disturbances (PROMIS), at baseline, post-program, and 2 months after RISE. FINDINGS: Average attendance in-person was 2.8 sessions and remotely 1.4 sessions (4.2/6 sessions). Participants demonstrating total burnout reduced from 50.0% at baseline to 9.1% post-program. Participants demonstrating professional fulfillment were 8.3% at baseline and 27.3% post-program. Paired samples t-tests revealed statistically significant improvements in burnout, professional fulfillment, interpersonal disengagement, stress, resilience, anxiety, and depression at post-program compared with baseline (N = 12, all ps < .05). At 2-month follow-up, statistically significant improvements in interpersonal disengagement, resilience, and mindfulness (N = 11, all ps < .05) compared with baseline were reported. CONCLUSIONS/APPLICATION TO PRACTICE: RISE is feasible within a workday and may address burnout and other psychological health measures in physicians with effects potentially sustainable over 2 months. Occupational health practitioners in health care should consider this type of intervention for their workers.


Asunto(s)
Agotamiento Profesional/prevención & control , Neonatólogos/psicología , Médicos/psicología , Yoga/psicología , Centros Médicos Académicos , Adulto , Anciano , Boston , Agotamiento Profesional/psicología , Femenino , Humanos , Persona de Mediana Edad , Atención Plena , Obstetricia , Estrés Laboral/prevención & control , Proyectos Piloto , Resiliencia Psicológica , Encuestas y Cuestionarios
4.
Cardiovasc Diagn Ther ; 10(5): 1691-1695, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33224782

RESUMEN

Prenatal closure of the ductus arteriosus (DA) can lead to cardiovascular dysfunction resulting in pulmonary hypertension (PH), progressive right heart failure, fetal hydrops, and fetal or neonatal demise. Supportive therapies-including mechanical ventilation, oxygen, and nitric oxide (NO)-have been employed with variable success among infants born full term, but there is no widely accepted management of prenatal closure of the DA, particularly for preterm infants. We present the case of an infant born at 31 weeks' gestation with right ventricular (RV) dysfunction and PH due to prenatal ductal closure, who was successfully treated with milrinone, resulting in full recovery of cardiac function. Prenatal ductal closure is rare, particularly under 32 weeks gestation, but should be suspected in cases of postnatal hypoxemia in the absence of significant lung disease or structural heart disease. Milrinone may be considered as a therapeutic agent to treat both PH and RV dysfunction in preterm infants status post in utero closure of the DA.

5.
F1000Res ; 7: 616, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30271580

RESUMEN

Background: There is a need to prevent and treat infection in newborns. One approach is administration of antimicrobial proteins and peptides (APPs) such as LL-37, a membrane-active cathelicidin antimicrobial peptide, and mannose-binding lectin (MBL), a pattern-recognition protein that binds to microbial surface polysaccharides resulting in opsonization and complement activation. Low plasma/serum levels of LL-37 and of MBL have been correlated with infection and exogenous administration of these agents may enhance host defense. Methods: The antimicrobial activity of LL-37 (15 µg/ml) or rMBL (0.5, 2 and 10 µg/ml) was tested in hirudin-anticoagulated preterm and term human cord blood (N = 12-14) against Staphylococcus aureus (SA) USA 300 (2x10 4 CFU/ml), Staphylococcus epidermis (SE) 1457 (2x10 4 CFU/ml) and Candida albicans (CA) SC5314 (1x10 4 CFU/ml). After incubation (1, 45, or 180 min), CFUs were enumerated by plating blood onto agar plates. Supernatants were collected for measurement of MBL via ELISA. Results: Preterm cord blood demonstrated impaired endogenous killing capacity against SA and SE compared to term blood. Addition of LL-37 strongly enhanced antimicrobial/antifungal activity vs SA, SE and CA in term blood and SE and CA in preterm blood. By contrast, rMBL showed modest fungistatic activity vs CA in a sub-analysis of term newborns with high basal MBL levels. Baseline MBL levels varied within preterm and term cohorts with no correlation to gestational age. In summary, exogenous LL-37 demonstrated significant antimicrobial activity against SA, SE and CA in term and SE and CA in preterm human blood tested in vitro. rMBL demonstrated modest antifungal activity in term cord blood of individuals with high baseline MBL levels. Conclusions: To the extent that our in vitro results predict the effects of APPs in vivo, development of APPs for prevention and treatment of infection should take into account host age as well as the target pathogen.


Asunto(s)
Catelicidinas/metabolismo , Sangre Fetal/inmunología , Lectina de Unión a Manosa/metabolismo , Péptidos Catiónicos Antimicrobianos/farmacología , Candida albicans/efectos de los fármacos , Catelicidinas/farmacología , Femenino , Sangre Fetal/química , Edad Gestacional , Humanos , Recién Nacido , Masculino , Lectina de Unión a Manosa/farmacología , Proteínas Recombinantes/metabolismo , Staphylococcus aureus , Staphylococcus epidermidis/efectos de los fármacos
6.
Front Immunol ; 9: 29, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29416539

RESUMEN

Immunization is key to protecting term and preterm infants from a heightened risk of infection. However, preterm immunity is distinct from that of the term, limiting its ability to effectively respond to vaccines routinely given at birth, such as hepatitis B vaccine (HBV). As part of the Expanded Program on Immunization, HBV is often given together with the live-attenuated vaccine Bacille Calmette-Guérin (BCG), known to activate multiple pattern-recognition receptors. Of note, some clinical studies suggest BCG can enhance efficacy of other vaccines in term newborns. However, little is known about whether BCG can shape Th-polarizing cytokine responses to HBV nor the age-dependency of such effects, including whether they may extend to the preterm. To characterize the effects of BCG on HBV immunogenicity, we studied individual and combined administration of these vaccines to cord newborn and adult human whole blood and mononuclear cells in vitro and to neonatal and adult mice in vivo. Compared to either BCG or HBV alone, (BCG + HBV) synergistically enhanced in vitro whole blood production of IL-1ß, while (BCG + HBV) also promoted production of several cytokines/chemokines in all age groups, age-specific enhancement included IL-12p70 in the preterm and GM-CSF in the preterm and term. In human mononuclear cells, (BCG + HBV) enhanced mRNA expression of several genes including CSF2, which contributed to clustering of genes by vaccine treatment via principle component analysis. To assess the impact of BCG on HBV immunization, mice of three different age groups were immunized subcutaneously with, BCG, HBV, (BCG + HBV) into the same site; or BCG and HBV injected into separate sites. Whether injected into a separate site or at the same site, co-administration of BCG with HBV significantly enhanced anti-HBV IgG titers in mice immunized on day of life-0 or -7, respectively, but not in adult mice. In summary, our data demonstrate that innate and adaptive vaccine responses of preterm and term newborns are immunologically distinct. Furthermore, BCG or "BCG-like" adjuvants should be further studied as a promising adjuvantation approach to enhance immunogenicity of vaccines to protect these vulnerable populations.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Vacuna BCG/administración & dosificación , Vacunas contra Hepatitis B/administración & dosificación , Inmunogenicidad Vacunal/efectos de los fármacos , Adulto , Animales , Animales Recién Nacidos , Citocinas/genética , Citocinas/inmunología , Femenino , Sangre Fetal , Humanos , Recién Nacido , Recien Nacido Prematuro , Leucocitos Mononucleares/inmunología , Masculino , Ratones Endogámicos C57BL , Nacimiento Prematuro , Nacimiento a Término , Adulto Joven
7.
JCI Insight ; 2(6): e91020, 2017 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-28352660

RESUMEN

Infection is the most common cause of mortality in early life, and immunization is the most promising biomedical intervention to reduce this burden. However, newborns fail to respond optimally to most vaccines. Adjuvantation is a key approach to enhancing vaccine immunogenicity, but responses of human newborn leukocytes to most candidate adjuvants, including most TLR agonists, are functionally distinct. Herein, we demonstrate that 3M-052 is a locally acting lipidated imidazoquinoline TLR7/8 agonist adjuvant in mice, which, when properly formulated, can induce robust Th1 cytokine production by human newborn leukocytes in vitro, both alone and in synergy with the alum-adjuvanted pneumococcal conjugate vaccine 13 (PCV13). When admixed with PCV13 and administered i.m. on the first day of life to rhesus macaques, 3M-052 dramatically enhanced generation of Th1 CRM-197-specific neonatal CD4+ cells, activation of newborn and infant Streptococcus pneumoniae polysaccharide-specific (PnPS-specific) B cells as well as serotype-specific antibody titers, and opsonophagocytic killing. Remarkably, a single dose at birth of PCV13 plus 0.1 mg/kg 3M-052 induced PnPS-specific IgG responses that were approximately 10-100 times greater than a single birth dose of PCV13 alone, rapidly exceeding the serologic correlate of protection, as early as 28 days of life. This potent immunization strategy, potentially effective with one birth dose, could represent a new paradigm in early life vaccine development.


Asunto(s)
Vacunas Neumococicas/administración & dosificación , Vacunas Neumococicas/inmunología , Receptor Toll-Like 7/agonistas , Receptor Toll-Like 8/agonistas , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/inmunología , Adyuvantes Inmunológicos/farmacología , Adulto , Animales , Linfocitos B/inmunología , Células Cultivadas , Humanos , Recién Nacido , Macaca mulatta , Linfocitos T/inmunología
8.
Circ Res ; 95(1): 109-16, 2004 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-15178641

RESUMEN

Systemic sclerosis (SSc) skin lesions are characterized by disturbed vessel morphology with enlarged capillaries and an overall reduction in capillary density, suggesting a deregulated, insufficient angiogenic response. It has been postulated that this phenomenon is due to reduced expression of the potent angiogenic factor vascular endothelial growth factor (VEGF). In contrast to this hypothesis, we demonstrate that the expression of both VEGF and its receptors VEGFR-1 and VEGFR-2 is dramatically upregulated in skin specimens of SSc patients throughout different disease stages. Interestingly, upregulation of VEGF was not mediated by hypoxia-inducible transcription factor-1 (HIF-1) as indicated by only a weak expression of the oxygen-sensitive alpha-subunit of HIF-1 in the skin of SSc patients. This was unexpected on measuring low Po2 values in the SSc skin by using a polarographic oxygen microelectrode system. Considering our observation that PDGF and IL-1beta costimulated VEGF expression, we propose that chronic and uncontrolled VEGF upregulation that is mediated by an orchestrated expression of cytokines rather than VEGF downregulation is the cause of the disturbed vessel morphology in the skin of SSc patients. Consequently, for therapeutic approaches aiming to improve tissue perfusion in these patients, a controlled expression and timely termination of VEGF signaling appears to be crucial for success of proangiogenic therapies.


Asunto(s)
Receptores de Factores de Crecimiento Endotelial Vascular/biosíntesis , Esclerodermia Sistémica/metabolismo , Piel/irrigación sanguínea , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Hipoxia de la Célula , Citocinas/farmacología , Proteínas de Unión al ADN/biosíntesis , Dermis/citología , Fibroblastos/metabolismo , Humanos , Factor 1 Inducible por Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia , Neovascularización Fisiológica , Proteínas Nucleares/biosíntesis , Esclerodermia Sistémica/genética , Esclerodermia Sistémica/patología , Piel/patología , Factores de Transcripción/biosíntesis , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/genética
9.
FASEB J ; 17(6): 761-3, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12594177

RESUMEN

The heterodimeric hypoxia-inducible factor (HIF)-1 is a master regulator of oxygen homeostasis. Protein stability and transactivation function of the alpha subunit are controlled by iron- and oxygen-dependent hydroxylation of proline and asparagine residues. The anti-mycotic ciclopirox olamine (CPX) is a lipophilic bidentate iron chelator that stabilizes HIF-1alpha under normoxic conditions at lower concentrations than other iron chelators, probably by inhibiting HIF-1alpha hydroxylation. As shown by the inhibition of iron-dependent quenching of FITC-labeled deferoxamine (DFX) fluorescence, CPX appears to have an even higher affinity for iron than DFX. Initial observations that treatment with 1% CPX, but not with placebo, occasionally caused reddening of wound margins in a mouse skin wound model prompted us to investigate the capability of CPX to induce angiogenesis. CPX-induced HIF-1-mediated reporter gene activity and endogenous HIF-1 target gene expression, including elevation of transcription, mRNA, and protein levels of the vascular endothelial growth factor (VEGF). In the chick chorioallantoic membrane assay, inert polymer disks containing CPX but not the solvent alone induced angiogenesis. In summary, these results suggest that CPX induces angiogenesis in vivo via HIF-1 and VEGF induction. Therefore, CPX might serve as an alternative to recombinant VEGF treatment or to VEGF gene therapy for therapeutic angiogenesis.


Asunto(s)
Antifúngicos/farmacología , Linfocinas/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Piridonas/farmacología , Factores de Transcripción/efectos de los fármacos , 2,2'-Dipiridil/farmacología , Alantoides/irrigación sanguínea , Animales , Sitios de Unión/genética , Unión Competitiva , Células CHO , Embrión de Pollo , Corion/irrigación sanguínea , Ciclopirox , Cricetinae , Deferoxamina/farmacología , Factores de Crecimiento Endotelial/biosíntesis , Factores de Crecimiento Endotelial/genética , Regulación de la Expresión Génica/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/genética , Hierro/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Luciferasas/genética , Luciferasas/metabolismo , Linfocinas/biosíntesis , Linfocinas/genética , Ratones , Piridonas/metabolismo , Conejos , Ratas , Proteínas Recombinantes de Fusión/efectos de los fármacos , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Piel/irrigación sanguínea , Piel/efectos de los fármacos , Piel/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
10.
FASEB J ; 16(3): 411-3, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11790723

RESUMEN

In the first-trimester mammalian fetus, skin wounds heal with perfect reconstitution of the dermal architecture without scar formation. Understanding environmental molecular regulation in fetal wound healing may reveal scar-limiting therapeutical strategies for the prevention of postnatal scarring wound repair. Therefore, we performed studies on fetal skin oxygenation and skin and wound expression of hypoxia-inducible factor 1alpha (HIF-1alpha) in the sheep model in vivo and performed studies on the potential relevance of HIF-1alpha during wound healing in vitro. Skin oxygen partial pressure levels were hypoxic throughout normal development. In nonscarring fetal skin at gestation day (GD)60, HIF-1alpha could be detected neither in healthy nor in wounded tissue. At GD100, in wounds with minimal scar formation, HIF-1alpha was expressed in fibroblasts and was markedly up-regulated at the wound edge. In scarring fetal wounds at GD120, HIF-1alpha was predominantly expressed in inflammatory cells. Expression of transforming growth factor beta3 (TGF-beta3), a potent antiscarring cytokine, overlapped with HIF-1a expression at GD100. HIF-1alpha-deficient mouse embryonic fibroblasts showed impaired migratory capabilities and demonstrated that TGF-beta3, but not proscarring TGF-beta1, manifests hypoxia- and HIF-1alpha-dependent regulation. In conclusion, HIF-1alpha-dependent regulation of a potent antiscarring cytokine may provide new strategies for antiscarring manipulation of wound healing.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Feto/fisiología , Proteínas Nucleares/biosíntesis , Piel/embriología , Factores de Transcripción , Factor de Crecimiento Transformador beta/biosíntesis , Cicatrización de Heridas , Animales , Hipoxia de la Célula , Movimiento Celular , Células Cultivadas , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Feto/anatomía & histología , Fibroblastos/fisiología , Factor 1 Inducible por Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia , Inmunohistoquímica , Ratones , Modelos Biológicos , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Ovinos , Piel/metabolismo , Enfermedades de la Piel/genética , Enfermedades de la Piel/metabolismo , Activación Transcripcional , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/inmunología , Factor de Crecimiento Transformador beta3
11.
In Vivo ; 16(6): 431-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12494886

RESUMEN

BACKGROUND: Poor tumour oxygenation is associated with radiation resistance. The recording of pre-treatment oxygenation status has been shown to be of prognostic relevance. MATERIAL AND METHODS: Eleven dogs with spontaneously arising soft tissue sarcomas were included in this study. Oxygen partial pressure measurements (pO2) were performed with the Eppendorf method. RESULTS: The mean of median pO2 was 9.6 mmHg (range: 0.1-30 mmHg). Four of the nine dogs included in the statistical analysis showed a median pO2 < or = 2.5 mmHg. The natural logarithm of the hypoxic subvolume correlated with the hypoxic fraction < or = 2.5 mmHg (p = 0.0712) and < or 5 mmHg (p = 0.0988). Mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) correlated significantly to several oxygen parameters. CONCLUSION: Hypoxia exists in spontaneous canine soft tissue sarcomas and the dog can be used as a reliable model for repeated oxygenation measurements. Ultrasonography assures reliability of needle placement.


Asunto(s)
Enfermedades de los Perros/metabolismo , Oxígeno/metabolismo , Sarcoma/veterinaria , Neoplasias de los Tejidos Blandos/veterinaria , Animales , Monitoreo de Gas Sanguíneo Transcutáneo/veterinaria , Enfermedades de los Perros/radioterapia , Perros , Electrodos de Iones Selectos , Estadificación de Neoplasias/veterinaria , Polarografía/veterinaria , Pronóstico , Radioterapia/veterinaria , Sarcoma/metabolismo , Sarcoma/radioterapia , Neoplasias de los Tejidos Blandos/metabolismo , Neoplasias de los Tejidos Blandos/radioterapia , Ultrasonografía/veterinaria
12.
Pulm Circ ; 4(4): 619-29, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25610598

RESUMEN

The combination of a vascular endothelial growth factor receptor antagonist, Sugen 5416 (SU5416), and chronic hypoxia is known to cause pronounced pulmonary hypertension (PH) with angioobliterative lesions in rats and leads to exaggerated PH in mice as well. We sought to determine whether weekly SU5416 injections during 3 weeks of hypoxia leads to long-term development of angioobliterative lesions and sustained or progressive PH in mice. Male C57BL/6J mice were injected with SU5416 (SuHx) or vehicle (VehHx) weekly during 3 weeks of exposure to 10% oxygen. Echocardiographic and invasive measures of hemodynamics and pulmonary vascular morphometry were performed after the 3-week hypoxic exposure and after 10 weeks of recovery in normoxia. SuHx led to higher right ventricular (RV) systolic pressure and RV hypertrophy than VehHx after 3 weeks of hypoxia. Ten weeks after hypoxic exposure, RV systolic pressure decreased but remained elevated in SuHx mice compared with VehHx or normoxic control mice, but RV hypertrophy had resolved. After 3 weeks of hypoxia and 10 weeks of follow-up in normoxia, tricuspid annular plane systolic excursion was significantly decreased, indicating decreased systolic RV function. Very few angioobliterative lesions were found at the 10-week follow-up time point in SuHx mouse lungs. In conclusion, SU5416 combined with 3 weeks of hypoxia causes a more profound PH phenotype in mice than hypoxia alone. PH persists over 10 weeks of normoxic follow-up in SuHx mice, but significant angioobliterative lesions do not occur, and neither PH nor RV dysfunction worsens. The SuHx mouse model is a useful adjunct to other PH models, but the search will continue for a mouse model that better recapitulates the human phenotype.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA