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1.
Transfusion ; 61 Suppl 1: S286-S293, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34269456

RESUMEN

BACKGROUND: Hemorrhage is the leading cause of death in trauma patients with most fatalities occurring before reaching a higher level of care-this applies to both the civilian setting and the military combat setting. Hemostatic resuscitation with increased emphasis on blood transfusion while limiting use of crystalloids has become routine in trauma care. However, the prehospital setting-especially in combat-presents unique challenges with regard to storage, transport, and administration. We sought to evaluate available technology on the market for storage and administration technology that is relevant to the prehospital setting. STUDY DESIGN AND METHODS: We conducted a market review of available technology through subject-matter expert inquiry, reviews of published literature, reviews of Federal Drug Administration databases, internal military publications, and searches of Google. RESULTS: We reviewed and described a total of 103 blood transporters, 22 infusers, and 6 warmers. CONCLUSIONS: The risk of on-scene fatality in trauma patients and recent developments in trauma care demonstrate the need for prehospital transfusion. These transfusions have been logistically prohibited in many operations. We have reviewed the current commercially available equipment and recommended pursuit of equipment that improves accessibility to field transfusion. Current technology has limited applicability for the prehospital setting and is further limited for the military setting.


Asunto(s)
Almacenamiento de Sangre , Transfusión Sanguínea , Transportes , Animales , Almacenamiento de Sangre/métodos , Transfusión Sanguínea/instrumentación , Transfusión Sanguínea/métodos , Hospitales , Humanos , Transportes/instrumentación
2.
Front Neuroendocrinol ; 54: 100773, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31344387

RESUMEN

Proopiomelanocortin (POMC) is a key mediator of satiety. Epigenetic marks such as DNA methylation may modulate POMC expression and provide a biological link between early life exposures and later phenotype. Animal studies suggest epigenetic marks at POMC are influenced by maternal energy excess and restriction, prenatal stress and Triclosan exposure. Postnatal factors including energy excess, folate, vitamin A, conjugated linoleic acid and leptin may also affect POMC methylation. Recent human studies suggest POMC DNA methylation is influenced by maternal nutrition in early pregnancy and associated with childhood and adult obesity. Studies in children propose a link between POMC DNA methylation and elevated lipids and insulin, independent of body habitus. This review brings together evidence from animal and human studies and suggests that POMC is sensitive to nutritional programming and is associated with a wide range of weight-related and metabolic outcomes.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Trastornos del Metabolismo de la Glucosa/metabolismo , Fenómenos Fisiológicos de la Nutrición , Obesidad/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Proopiomelanocortina/metabolismo , Animales , Femenino , Trastornos del Metabolismo de la Glucosa/etiología , Trastornos del Metabolismo de la Glucosa/genética , Humanos , Obesidad/etiología , Obesidad/genética , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Proopiomelanocortina/genética
3.
BMC Health Serv Res ; 19(1): 391, 2019 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-31208427

RESUMEN

BACKGROUND: Fall prevention is a priority in Canadian tertiary rehabilitation hospitals. We aimed to understand the perspectives of hospital administrators on the challenges experienced when implementing fall prevention policies/procedures for patients with spinal cord injury (SCI) in tertiary rehabilitation hospitals. METHODS: Semi-structured interviews were conducted with 10 administrators employed in six Canadian tertiary rehabilitation hospitals. Guided by an interpretive description framework, interviews were analyzed using a constant comparison approach. RESULTS: Challenges with fall prevention experienced by administrators fell into the three categories: 1) fall prevention policy and procedural challenges (e.g. fall prevention policy not SCI-specific, expectation of zero falls, determining contributing factors, learning from falls, and overall effectiveness of the fall prevention policy), 2) clinician-related challenges (e.g. variable staff adherence with the organizations' fall prevention procedures, inconsistent delivery of fall prevention education, and integrating individualized fall risks to guide clinical practice), and 3) patient-related challenges (e.g. balancing risk vs independence and rehabilitation progress, responsibility for fall prevention, and non-preventable falls). CONCLUSIONS: Fall prevention policies/procedures required by the hospitals were insufficient for clinical practice in SCI rehabilitation.


Asunto(s)
Accidentes por Caídas/prevención & control , Accidentes por Caídas/estadística & datos numéricos , Administradores de Hospital , Hospitales de Rehabilitación , Traumatismos de la Médula Espinal/rehabilitación , Canadá/epidemiología , Recolección de Datos , Conductas Relacionadas con la Salud , Investigación sobre Servicios de Salud , Humanos , Guías de Práctica Clínica como Asunto , Factores de Riesgo , Traumatismos de la Médula Espinal/epidemiología
4.
Gene Ther ; 21(4): 413-21, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24572787

RESUMEN

The Hedgehog (Hh) pathway is a crucial regulator of muscle development during embryogenesis. We have previously demonstrated that Sonic hedgehog (Shh) regulates postnatal myogenesis in the adult skeletal muscle both directly, by acting on muscle satellite cells, and indirectly, by promoting the production of growth factors from interstitial fibroblasts. Here, we show that in mdx mice, the murine equivalent of Duchenne muscular dystrophy in humans, progression of the dystrophic pathology corresponds to progressive inhibition of the Hh signaling pathway in the skeletal muscle. We also show that the upregulation of the Hh pathway in response to injury and during regeneration is significantly impaired in mdx muscle. Shh treatment increases the proliferative potential of satellite cells isolated from the muscles of mdx mice. This treatment also increases the production of proregenerative factors, such as insulin-like growth factor-1 and vascular endothelial growth factor, from fibroblasts isolated from the muscle of mdx mice. In vivo, overexpression of the Hh pathway using a plasmid encoding the human Shh gene promotes successful regeneration after injury in terms of increased number of proliferating myogenic cells and newly formed myofibers, as well as enhanced vascularization and decreased fibrosis.


Asunto(s)
Terapia Genética , Proteínas Hedgehog/genética , Músculo Esquelético/crecimiento & desarrollo , Distrofia Muscular de Duchenne/terapia , Regeneración/genética , Animales , Proteínas Hedgehog/uso terapéutico , Humanos , Ratones , Ratones Endogámicos mdx , Desarrollo de Músculos/genética , Músculo Esquelético/lesiones , Distrofia Muscular de Duchenne/genética , Mioblastos/patología , Factor A de Crecimiento Endotelial Vascular/genética
5.
Vaccine ; 41(25): 3772-3781, 2023 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-37198022

RESUMEN

BACKGROUND: In the United States (US), half of new human papillomavirus (HPV) infections occur among young people aged 15-24 years. Despite the effectiveness of HPV vaccination in protecting against HPV-associated cancers, its coverage among adolescents remains suboptimal. This study examined the association of sociodemographic characteristics and HPV vaccination hesitancy with HPV vaccination coverage in five US states with disproportionately low adolescent coverage rates compared to the national average. METHODS: Responses to an online Qualtrics survey from 926 parents of children aged 9-17 years in Arkansas, Mississippi, Missouri, Tennessee, and Southern Illinois in July 2021 were analyzed using multivariate logistic regression to estimate the association of sociodemographic characteristics and HPV vaccination hesitancy with HPV vaccination coverage. RESULTS: Of the parents, 78 % were female, 76 % were non-Hispanic White, 61.9 % lived in rural areas, 22 % were classified as HPV vaccine hesitant, and 42 % had vaccinated their oldest child between the ages of 9-17 years against HPV. Children of vaccine hesitant parents were less likely to have received any doses of the HPV vaccine than children of non-vaccine hesitant parents (AOR: 0.17, 95 % CI:0.11-0.27). Male children were less likely to have initiated the HPV vaccine series than female children (AOR: 0.70, 95 % CI:0.50-0.97). Older children (13-17 vs 9-12 years), receiving the meningococcal conjugate or most recent seasonal influenza vaccine were all associated with higher likelihoods of receiving any doses of the HPV vaccine (AOR: 6.01, 95 % CI:3.98-9.08; AOR: 2.24, 95 % CI:1.27-3.95; AOR: 2.41, 95 % CI:1.73-3.36, respectively). CONCLUSIONS: Adolescent HPV vaccination coverage remains low in our targeted states. Children's age, sex, and parental vaccine hesitancy were significantly associated with likelihood of HPV vaccination. These findings offer the opportunity for targeted interventions among parents in regions with low vaccine uptake and underscore the importance of developing and implementing strategies to address parental HPV vaccination hesitancy to improve uptake in the US.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Adolescente , Niño , Estados Unidos , Humanos , Masculino , Femenino , Vacilación a la Vacunación , Cobertura de Vacunación , Infecciones por Papillomavirus/prevención & control , Vacunación , Padres , Arkansas , Conocimientos, Actitudes y Práctica en Salud
6.
J Spec Oper Med ; 23(2): 13-18, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37094291

RESUMEN

BACKGROUND: Airway obstruction is the second leading cause of potentially preventable death on the battlefield. The treatment for airway obstruction is intubation or advanced airway adjunct, which has a known risk of aspiration. We sought to describe the variables associated with aspiration pneumonia after prehospital airway intervention. METHODS: This is a sub-analysis of previously described data from the Department of Defense Trauma Registry (DoDTR) from 2007 to 2020. We included casualties that had at least one prehospital airway intervention with documentation of subsequent aspiration pneumonia or pneumonia within three days of the intervention. We used a generalized linear model with Firth bias estimates to test for associations. RESULTS: There were 1,509 casualties that underwent prehospital airway device placement. Of these, 41 (2.7%) met inclusion criteria into the aspiration pneumonia cohort. The demographics had no statistical difference between the groups. The non-aspiration cohort had fewer median ventilator days (2 versus 6, p < 0.001), intensive care unit days (2 versus 7, p < 0.001, and hospital days [3 versus 8, p < 0.001]). Survival was lower in the non-aspiration cohort (74.2% versus 90.2%, p = 0.017). The administration of succinylcholine was higher in the non-aspiration cohort (28.0% versus 12.2%, p = 0.031). In our multivariable model, only the administration of succinylcholine was significant and was associated with lower probability of aspiration pneumonia (odds ratio 0.56). CONCLUSION: Overall, the incidence of aspiration pneumonia was low in our cohort. The administration of succinylcholine was associated with a lower odds of developing aspiration pneumonia.


Asunto(s)
Obstrucción de las Vías Aéreas , Servicios Médicos de Urgencia , Neumonía por Aspiración , Humanos , Manejo de la Vía Aérea , Succinilcolina , Obstrucción de las Vías Aéreas/terapia , Neumonía por Aspiración/epidemiología , Neumonía por Aspiración/etiología , Sistema de Registros
7.
Res Sq ; 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37693576

RESUMEN

Background: Cardiovascular disease (CVD) is a complex disease, and genetic factors contribute individually or cumulatively to CVD risk. While African American women and men are disproportionately affected by CVD, their lack of representation in genomic investigations may widen disparities in health. We investigated the associations of cardiometabolic polygenic risk scores (PRSs) with CVD risk in African Americans. Methods: We used the Jackson Heart Study, a prospective cohort study of CVD in African American adults and the predicted atherosclerotic cardiovascular disease (ASCVD) 10-year risk. We included 40-79 years old adults without a history of coronary heart disease (CHD) or stroke at baseline. We derived genome-wide PRSs for systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, LDL cholesterol, hemoglobin A1c (HbA1c), triglycerides, and C-reactive protein (CRP) separately for each of the participants, using African-origin UK Biobank participants' genome-wide association summary statistics. We estimated the associations between PRSs and 10-year predicted ASCVD risk adjusting for age, sex, study visit date, and genetic ancestry using linear and logistic regression models. Results: Participants (n=2,077) were 63% female and 66% never-smokers. They had mean (SD) 56 (10) years of age, 127.8 (16.3) mmHg SBP, 76.3 (8.7) mmHg DBP, 200.4 (40.2) mg/dL total cholesterol, 51.7 (14.7) mg/dL HDL cholesterol, 127.2 (36.7) mg/dL LDL cholesterol, 6.0 (1.3) mmol/mol HbA1c, 108.9 (81.7) mg/dL triglycerides and 0.53 (1.1) CRP. Their median (interquartile range) predicted 10-year predicted ASCVD risk was 8.0 (4.0-15.0). Participants in the >75th percentile for HbA1c PRS had 1.42 percentage-point greater predicted 10-year ASCVD risk (1.42 [95% CI: 0.58-2.26]) and higher odds of ≥10% predicted 10-year ASCVD risk (OR: 1.46 [95% CI: 1.03-2.07]) compared with those in the <25th percentile for HbA1c PRS. Participants in the >75th percentile for SBP PRS had higher odds of ≥10% predicted 10-year ASCVD risk (OR: 1.52 [95% CI: 1.07-2.15]) compared with those in the <25th percentile for SBP PRS. Conclusion: Among 40-79 years old African Americans without CHD and stroke, higher PRSs for HbA1c and SBP were associated with CVD risk. PRSs may help stratify individuals based on their clinical risk factors for CVD early prevention and clinical management.

8.
Nat Med ; 5(4): 434-8, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10202935

RESUMEN

Endothelial progenitor cells (EPCs) have been isolated from circulating mononuclear cells in human peripheral blood and shown to be incorporated into foci of neovascularization, consistent with postnatal vasculogenesis. We determined whether endogenous stimuli (tissue ischemia) and exogenous cytokine therapy (granulocyte macrophage-colony stimulating factor, GM-CSF) mobilize EPCs and thereby contribute to neovascularization of ischemic tissues. The development of regional ischemia in both mice and rabbits increased the frequency of circulating EPCs. In mice, the effect of ischemia-induced EPC mobilization was demonstrated by enhanced ocular neovascularization after cornea micropocket surgery in mice with hindlimb ischemia compared with that in non-ischemic control mice. In rabbits with hindlimb ischemia, circulating EPCs were further augmented after pretreatment with GM-CSF, with a corresponding improvement in hindlimb neovascularization. There was direct evidence that EPCs that contributed to enhanced corneal neovascularization were specifically mobilized from the bone marrow in response to ischemia and GM-CSF in mice transplanted with bone marrow from transgenic donors expressing beta-galactosidase transcriptionally regulated by the endothelial cell-specific Tie-2 promoter. These findings indicate that circulating EPCs are mobilized endogenously in response to tissue ischemia or exogenously by cytokine therapy and thereby augment neovascularization of ischemic tissues.


Asunto(s)
Células de la Médula Ósea/fisiología , Endotelio Vascular/fisiología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Isquemia/fisiopatología , Neovascularización Fisiológica/fisiología , Células Madre/fisiología , Animales , Antígenos de Diferenciación , Células de la Médula Ósea/citología , Trasplante de Médula Ósea , Córnea/irrigación sanguínea , Endotelio Vascular/citología , Miembro Posterior/irrigación sanguínea , Isquemia/tratamiento farmacológico , Masculino , Ratones , Ratones Transgénicos , Conejos , Células Madre/citología
9.
Nat Med ; 6(4): 405-13, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10742147

RESUMEN

Ischemic peripheral neuropathy is a frequent, irreversible complication of lower extremity vascular insufficiency. We investigated whether ischemic peripheral neuropathy could be prevented and/or reversed by gene transfer of an endothelial cell mitogen designed to promote therapeutic angiogenesis. Intramuscular gene transfer of naked DNA encoding vascular endothelial growth factor (VEGF) simultaneously with induction of hindlimb ischemia in rabbits abrogated the substantial decrease in motor and sensory nerve parameters, and nerve function recovered promptly. When gene transfer was administered 10 days after induction of ischemia, nerve function was restored earlier and/or recovered faster than in untreated rabbits. These findings are due in part to enhanced hindlimb perfusion. In addition, however, the demonstration of functional VEGF receptor expression by Schwann cells indicates a direct effect of VEGF on neural integrity as well. These findings thus constitute a new paradigm for the treatment of ischemic peripheral neuropathy.


Asunto(s)
Factores de Crecimiento Endotelial/genética , Técnicas de Transferencia de Gen , Terapia Genética , Isquemia/terapia , Linfocinas/genética , Enfermedades del Sistema Nervioso Periférico/terapia , Sistema Nervioso Periférico/irrigación sanguínea , Animales , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Factores de Crecimiento Endotelial/farmacología , Miembro Posterior/inervación , Miembro Posterior/metabolismo , Miembro Posterior/fisiopatología , Linfocinas/farmacología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuropilina-1 , Enfermedades del Sistema Nervioso Periférico/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Conejos , Ratas , Ratas Sprague-Dawley , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Factores de Crecimiento/genética , Receptores de Factores de Crecimiento/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular , Células de Schwann/efectos de los fármacos , Células de Schwann/fisiología , Factor A de Crecimiento Endotelial Vascular , Receptor 1 de Factores de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
10.
Nat Med ; 7(6): 706-11, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11385508

RESUMEN

Sonic hedgehog (Shh) is a prototypical morphogen known to regulate epithelial/mesenchymal interactions during embryonic development. We found that the hedgehog-signaling pathway is present in adult cardiovascular tissues and can be activated in vivo. Shh was able to induce robust angiogenesis, characterized by distinct large-diameter vessels. Shh also augmented blood-flow recovery and limb salvage following operatively induced hind-limb ischemia in aged mice. In vitro, Shh had no effect on endothelial-cell migration or proliferation; instead, it induced expression of two families of angiogenic cytokines, including all three vascular endothelial growth factor-1 isoforms and angiopoietins-1 and -2 from interstitial mesenchymal cells. These findings reveal a novel role for Shh as an indirect angiogenic factor regulating expression of multiple angiogenic cytokines and indicate that Shh might have potential therapeutic use for ischemic disorders.


Asunto(s)
Factores de Crecimiento Endotelial/metabolismo , Linfocinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Neovascularización Fisiológica/fisiología , Proteínas/metabolismo , Transducción de Señal , Transactivadores , Angiopoyetina 1 , Angiopoyetina 2 , Animales , Vasos Sanguíneos/anatomía & histología , Vasos Sanguíneos/fisiología , Neovascularización de la Córnea , Factores de Crecimiento Endotelial/genética , Femenino , Genes Reporteros , Proteínas Hedgehog , Miembro Posterior/irrigación sanguínea , Humanos , Inmunohistoquímica , Isquemia/terapia , Linfocinas/genética , Masculino , Glicoproteínas de Membrana/genética , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Miocardio/metabolismo , Receptores Patched , Proteínas/genética , Receptores de Superficie Celular , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/metabolismo , Flujo Sanguíneo Regional/fisiología , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
11.
Dalton Trans ; 49(5): 1570-1581, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31934703

RESUMEN

The interaction of Np(v) with borate was investigated in 0.1-5.0 M NaCl and 0.25-4.5 M MgCl2 solutions with 7.2 ≤ pHm ≤ 10.0 (pHm = -log[H+]) and 0.004 M ≤ [B]tot ≤ 0.16 M. Experiments were performed under an Ar-atmosphere at T = (22 ± 2) °C using a combination of under- and oversaturation solubility experiments, NIR spectroscopy, and extensive solid phase characterization. A bathochromic shift (≈5 nm) in the Np(v) band at λ = 980 nm indicates the formation of weak Np(v)-borate complexes under mildly alkaline pHm-conditions. The identification of an isosbestic point supports the formation of a single Np(v)-borate species in dilute MgCl2 systems, whereas a more complex aqueous speciation (eventually involving the formation of several Np(v)-borate species) is observed in concentrated MgCl2 solutions. The solubility of freshly prepared NpO2OH(am) remained largely unaltered in NaCl and MgCl2 solutions with [B]tot = 0.04 M within the timeframe of this study (t ≤ 300 days). At [B]tot = 0.16 M, a kinetically hindered but very significant drop in the solubility of Np(v) (3-4 log10-units, compared to borate-free systems) was observed in NaCl and dilute MgCl2 solutions with pHm ≤ 9. The drop in the solubility was accompanied by a clear change in the colour of the solid phase (from green to white-greyish). XRD and TEM analyses showed that the amorphous NpO2OH(am) "starting material" transformed into crystalline solid phases with similar XRD patterns in NaCl and MgCl2 systems. XPS, SEM-EDS and EXAFS further indicated that borate and Na/Mg participate stoichiometrically in the formation of such solid phases. Additional undersaturation solubility experiments using the newly formed Na-Np(v)-borate(cr) and Mg-Np(v)-borate(cr) compounds further confirmed the low solubility ([Np(v)]aq ≈ 10-6-10-7 M) of such solid phases in mildly alkaline pHm-conditions. The formation of these solid phases represents a previously unreported retention mechanism for the highly mobile Np(v) under boundary conditions (pHm, [B]tot, ionic strength) of relevance to certain repository concepts for nuclear waste disposal.

12.
Br J Cancer ; 101(3): 465-72, 2009 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-19603024

RESUMEN

BACKGROUND: We address the prognostic and predictive value of KRAS, PIK3CA and BRAF mutations for clinical outcomes in response to active agents in the treatment of metastatic colorectal cancer (mCRC). METHODS: We determined KRAS, BRAF and PIK3CA mutations in tumours from 168 patients treated for mCRC at two institutions. All patients received 5-FU-based first-line chemotherapy and treatment outcome was analysed retrospectively. RESULTS: KRAS, BRAF and PIK3CA mutations were present in 62 (37%), 13 (8%) and 26 (15%) cases, respectively. Multivariate analysis uncovered BRAF mutation as an independent prognostic factor for decreased survival (hazard ratio (HR) 4.0, 95% confidence interval (CI) 2.1-7.6). In addition, patients with BRAF-mutant tumours had significantly lower progression-free survival (PFS: HR 4.0, 95% CI 2.2-7.4) than those whose tumors that carried wild-type BRAF. Among 92 patients treated using chemotherapy and cetuximab as salvage therapy, KRAS mutation was associated with lack of response (P=0.002) and shorter PFS (P=0.09). BRAF (P=0.0005) and PIK3CA (P=0.01) mutations also predicted reduced PFS in response to cetuximab salvage therapy. CONCLUSIONS: These results underscore the potential of mutational profiling to identify CRCs with different natural histories or treatment responses. The adverse significance of BRAF mutation should inform patient selection and stratification in clinical trials.


Asunto(s)
Neoplasias Colorrectales/genética , Mutación , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Cetuximab , Fosfatidilinositol 3-Quinasa Clase I , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Valor Predictivo de las Pruebas , Pronóstico , Proteínas Proto-Oncogénicas p21(ras) , Terapia Recuperativa
13.
Science ; 224(4655): 1340-2, 1984 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-17837194

RESUMEN

Evidence of in situ metal (iron and manganese) deposition onto bacteria associated with rapidly sinking particles in the open ocean is reported. Below 100 meters, bacteria are found with extracellular capsules containing metal precipitates; the frequency of these capsules increases with depth. The capsular metal deposits appear to contribute a major portion of the weakly bound fraction of the particulate iron flux.

14.
Science ; 201(4353): 371-3, 1978 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-17793735

RESUMEN

In near-surface waters of the neritic zone, the fragile aggregate material called "marine snow" is enriched by a variety of planktonic organisms and detrital products of plankton. Here marine snow is a source of patchiness and taxonomic diversity for microplankton populations and is a likely food resource and recycling agent for fecal particles.

15.
Science ; 221(4606): 152-4, 1983 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-17769213

RESUMEN

Nitrogen fixation, apparently by bacterial endosymbionts, is associated with intertwining chains of two species of the diatom Rhizosolenia. In situ fixation rates were enhanced by incubation in the dark, whereas concurrent shipboard experiments either underestimated or did not detect nitrogen fixation. This is the first example of nitrogen fixation associated with a bacteria-diatom symbiosis in the pelagic zone, and it indicates that these systems may contribute a significant amount of "new" nitrogen to oligotrophic waters.

16.
Science ; 183(4129): 1085-7, 1974 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-4812036

RESUMEN

Injection of sodium arachidonate (1.4 milligrams per kilogram) into the marginal ear veins of rabbits caused death within 3 minutes. Histological examination showed platelet thrombi in the microvasculature of the lungs. Rabbits were protected from the lethal effects of arachidonic acid by pretreatment with aspirin. Fatty acids closely related to arachidonic acid did not cause death.


Asunto(s)
Ácidos Araquidónicos/toxicidad , Adhesividad Plaquetaria/efectos de los fármacos , Trombosis/inducido químicamente , Animales , Ácidos Araquidónicos/administración & dosificación , Ácidos Araquidónicos/antagonistas & inhibidores , Aspirina/farmacología , Muerte Súbita , Inyecciones Intravenosas , Microcirculación , Circulación Pulmonar/efectos de los fármacos , Conejos
17.
Science ; 275(5302): 964-7, 1997 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-9020076

RESUMEN

Putative endothelial cell (EC) progenitors or angioblasts were isolated from human peripheral blood by magnetic bead selection on the basis of cell surface antigen expression. In vitro, these cells differentiated into ECs. In animal models of ischemia, heterologous, homologous, and autologous EC progenitors incorporated into sites of active angiogenesis. These findings suggest that EC progenitors may be useful for augmenting collateral vessel growth to ischemic tissues (therapeutic angiogenesis) and for delivering anti- or pro-angiogenic agents, respectively, to sites of pathologic or utilitarian angiogenesis.


Asunto(s)
Endotelio Vascular/citología , Neovascularización Fisiológica , Células Madre/citología , Animales , Antígenos CD34/análisis , Biomarcadores/análisis , Diferenciación Celular , Separación Celular , Células Cultivadas , Endotelio Vascular/química , Citometría de Flujo , Miembro Posterior/irrigación sanguínea , Humanos , Isquemia/fisiopatología , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Ratones Transgénicos , Óxido Nítrico Sintasa/análisis , Conejos , Proteínas Tirosina Quinasas Receptoras/análisis , Receptores de Factores de Crecimiento/análisis , Receptores de Factores de Crecimiento Endotelial Vascular , Células Madre/química
18.
Science ; 200(4337): 52-4, 1978 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-345441

RESUMEN

Prostacyclin, a potent, naturally occurring prostaglandin exerts a variety of cardiovascular and cellular actions of potential value in acute myocardial ischemia. These properties include the reduction of systemic blood pressure without changing heart rate, the lowering of coronary vascular and total peripheral resistance, the inhibition of platelet aggregation and the concomitant formation of thromboxane B2, and the reduction of the release of lysosomal enzymes.


Asunto(s)
Epoprostenol/farmacología , Hemodinámica/efectos de los fármacos , Prostaglandinas/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Gatos , Circulación Coronaria/efectos de los fármacos , Enfermedad Coronaria/tratamiento farmacológico , Epoprostenol/uso terapéutico , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Lisosomas/efectos de los fármacos , Lisosomas/enzimología , Contracción Miocárdica/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Tromboxanos/sangre , Resistencia Vascular/efectos de los fármacos
19.
J Small Anim Pract ; 60(1): 32-37, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30209807

RESUMEN

OBJECTIVES: To determine whether the addition of metronomic chemotherapy improved outcome for dogs with splenic haemangiosarcoma treated with splenectomy and adjuvant maximum tolerated dose chemotherapy. MATERIALS AND METHODS: Medical records were examined retrospectively for dogs with splenic haemangiosarcoma that had undergone splenectomy followed by anthracycline-based chemotherapy. Thirty-nine dogs underwent splenectomy followed by maximum tolerated dose chemotherapy with an anthracycline, cyclophosphamide, or both (Group 1). Twenty-two dogs underwent splenectomy followed by adjuvant maximum tolerated dose chemotherapy with an anthracycline, cyclophosphamide, or both, plus metronomic chemotherapy (Group 2). Dogs in both groups were further separated into those treated with either maximum tolerated dose anthracycline or maximum tolerated dose anthracycline and cyclophosphamide. RESULTS: Median progression-free survival was 165 days and median overall survival time was 180 days in Group 1. Median progression-free survival was 185 days and median overall survival time was 212 days in Group 2. In both groups, the overall survival was shorter in dogs that had received maximum tolerated dose cyclophosphamide. CLINICAL SIGNIFICANCE: The addition of metronomic to maximum tolerated dose chemotherapy protocols does not appear to improve outcome in dogs with splenic haemangiosarcoma treated with splenectomy and maximum tolerated dose chemotherapy.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Enfermedades de los Perros/tratamiento farmacológico , Hemangiosarcoma/veterinaria , Administración Metronómica/veterinaria , Animales , Antraciclinas/administración & dosificación , Quimioterapia Adyuvante , Ciclofosfamida/administración & dosificación , Enfermedades de los Perros/cirugía , Perros , Femenino , Hemangiosarcoma/tratamiento farmacológico , Hemangiosarcoma/cirugía , Estimación de Kaplan-Meier , Masculino , Dosis Máxima Tolerada , Estudios Retrospectivos , Bazo/patología , Bazo/cirugía , Resultado del Tratamiento
20.
Exp Neurol ; 311: 265-273, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30393144

RESUMEN

Parkinson's disease is a neurodegenerative disorder that reduces a patients' quality of life by the relentless progression of motor and non-motor symptoms. Among the non-motor symptoms is a condition called neurogenic bladder that is associated with detrusor muscle underactivity or overactivity occurring from neurologic damage. In Parkinson's disease, Lewy-body-like protein aggregation inside neurons typically contributes to pathology. This is associated with dopaminergic neuron loss in substantia nigra pars compacta (SNc) and in ventral tegmental area (VTA), both of which play a role in micturition. GM1 gangliosides are mature glycosphingolipids that enhance normal myelination and are reduced in Parkinson's brain. To explore the role of mature gangliosides in vivo, we obtained GM2 Synthase knockout (KO) mice, which develop parkinsonian pathology including a loss of SNc dopaminergic neurons, which we reconfirmed. However, bladder function and innervation have never been assessed in this model. We compared GM2 Synthase KO and wild type (WT) littermates' urination patterns from 9 to 19 months of age by counting small and large void spots produced during 1 h tests. Because male and female mice had different patterns, we evaluated data by sex and genotype. Small void spots were significantly increased in 12-16 month GM2 Synthase KO females, consistent with overactive bladder. Similarly, at 9-12 month GM2 KO males tended to have more small void spots than WT males. As GM2 Synthase KO mice aged, both females and males had fewer small and large void spots, consistent with detrusor muscle underactivity. Ultrasounds confirmed bladder enlargement in GM2 Synthase KO mice compared to WT mice. Tyrosine hydroxylase (TH) immunohistochemistry revealed significant dopaminergic loss in GM2 Synthase KO VTA and SNc, and a trend toward TH loss in the GM2 KO periaqueductal gray (PAG) micturition centers. Levels of the nerve growth factor precursor, proNGF, were significantly increased in GM2 Synthase KO bladders and transmission electron micrographs showed atypical myelination of pelvic ganglion innervation in GM2 Synthase KO bladders. Cumulatively, our findings provide the first evidence that mature ganglioside loss affects micturition center TH neurons as well as proNGF dysregulation and abnormal innervation of the bladder. Thus, identifying therapies that will counteract these effects should be beneficial for those suffering from Parkinson's disease and related disorders.


Asunto(s)
Gangliósidos/deficiencia , N-Acetilgalactosaminiltransferasas/deficiencia , Trastornos Parkinsonianos/metabolismo , Vejiga Urinaria Neurogénica/metabolismo , Animales , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Femenino , Gangliósidos/genética , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , N-Acetilgalactosaminiltransferasas/genética , Trastornos Parkinsonianos/genética , Trastornos Parkinsonianos/fisiopatología , Vejiga Urinaria Neurogénica/genética , Vejiga Urinaria Neurogénica/fisiopatología
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