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1.
Pediatr Blood Cancer ; : e31217, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039777

RESUMEN

Germ cell tumors (GCT) are a complex, heterogeneous collection of tumors that may present in either gonadal or extragonadal sites. They consist of a variety of benign and malignant histologies that can occur at several locations throughout the body. An important component of treatment is surgical resection, and while the key components of resection are site specific, the universal goals of GCT resection include the complete resection of tumor without violating the tumor capsule, while preserving function of surrounding organs, minimizing morbidity, and assessing for regional spread.

2.
Ecol Food Nutr ; 63(2): 112-134, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38421255

RESUMEN

Our intersectional research explored food insecurity and job insecurity as predictors of healthcare insecurity and mental health challenges among households living in economic instability since the COVID19 pandemic began. The New York City COVID19 Research Team adapted a validated, web based, anonymous survey questionnaire using a Social Determinants of Health Framework. The study oversampled underserved populations with a total of 2,099 participants. We report strong associations between food insecurity and job insecurity among healthcare insecure households, and significant mental health challenges among food insecure and healthcare insecure households. This underscores the need for integrated social policies to protect underserved urban populations.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Salud Mental , Seguridad del Empleo , Marco Interseccional , Abastecimiento de Alimentos , Inseguridad Alimentaria , Atención a la Salud
3.
PLoS Comput Biol ; 17(10): e1009474, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34662342

RESUMEN

The role of heating, ventilation, and air-conditioning (HVAC) systems in the transmission of SARS-CoV-2 is unclear. To address this gap, we simulated the release of SARS-CoV-2 in a multistory office building and three social gathering settings (bar/restaurant, nightclub, wedding venue) using a well-mixed, multi-zone building model similar to those used by Wells, Riley, and others. We varied key factors of HVAC systems, such as the Air Changes Per Hour rate (ACH), Fraction of Outside Air (FOA), and Minimum Efficiency Reporting Values (MERV) to examine their effect on viral transmission, and additionally simulated the protective effects of in-unit ultraviolet light decontamination (UVC) and separate in-room air filtration. In all building types, increasing the ACH reduced simulated infections, and the effects were seen even with low aerosol emission rates. However, the benefits of increasing the fraction of outside air and filter efficiency rating were greatest when the aerosol emission rate was high. UVC filtration improved the performance of typical HVAC systems. In-room filtration in an office setting similarly reduced overall infections but worked better when placed in every room. Overall, we found little evidence that HVAC systems facilitate SARS-CoV-2 transmission; most infections in the simulated office occurred near the emission source, with some infections in individuals temporarily visiting the release zone. HVAC systems only increased infections in one scenario involving a marginal increase in airflow in a poorly ventilated space, which slightly increased the likelihood of transmission outside the release zone. We found that improving air circulation rates, increasing filter MERV rating, increasing the fraction of outside air, and applying UVC radiation and in-room filtration may reduce SARS-CoV-2 transmission indoors. However, these mitigation measures are unlikely to provide a protective benefit unless SARS-CoV-2 aerosol emission rates are high (>1,000 Plaque-forming units (PFU) / min).


Asunto(s)
Aire Acondicionado , COVID-19/transmisión , Calefacción , SARS-CoV-2 , Ventilación , Aerosoles , Microbiología del Aire , Movimientos del Aire , COVID-19/prevención & control , COVID-19/virología , Biología Computacional , Simulación por Computador , Humanos , Modelos Biológicos , Pandemias , SARS-CoV-2/efectos de la radiación , Interacción Social , Rayos Ultravioleta , Lugar de Trabajo
4.
J Surg Res ; 269: 51-58, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34520982

RESUMEN

BACKGROUND: Use of routine chest x-rays (CXR) following thoracostomy tube (TT) removal is highly variable and its utility is debated. We hypothesize that routine post-pull chest x-ray (PP-CXR) findings following TT removal in pediatric trauma would not guide the decision for TT reinsertion. METHODS: Patients ≤ 18 y who were not mechanically ventilated and undergoing final TT removal for a traumatic hemothorax (HTX) and/or pneumothorax (PTX) at a level I pediatric trauma center from 2010 to 2020 were retrospectively reviewed. The outcomes of interest were rate of PP-CXR and TT reinsertion rate following PP-CXR. Clinical predictors for worsened findings on PP-CXR were also assessed. RESULTS: Fifty-nine patients were included. A CXR after TT removal was performed in 57 patients (97%), with 28% demonstrating worsened CXR findings compared to the prior film. Except for higher ISS (p = 0.033), there were no demographic or clinical predictors for worsened CXR findings. However, they were more likely to have additional films following the TT removal (p = 0.008) than those with stable or improved PP-CXR findings. One (1.8%) asymptomatic child with worsened PP-CXR findings had TT reinsertion based purely on their worsened PP-CXR findings. CONCLUSIONS: The vast majority of PP-CXR did not guide TT reinsertion after pediatric thoracic trauma. Treatment algorithms may aid to reduce variability and potentially unnecessary routine films.


Asunto(s)
Neumotórax , Traumatismos Torácicos , Tubos Torácicos/efectos adversos , Niño , Humanos , Neumotórax/etiología , Neumotórax/cirugía , Estudios Retrospectivos , Traumatismos Torácicos/cirugía , Toracostomía/efectos adversos
5.
Lett Appl Microbiol ; 74(3): 302-310, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34826143

RESUMEN

The human oral cavity is host to a diverse microbiota. Much of what is known about the behaviour of oral microbes derives from studies of individual or several cultivated species, situations which do not totally reflect the function of organisms within more complex microbiota or multispecies biofilms. The number of validated models that allow examination of the role that biofilms play during oral cavity colonization is also limited. The CDC biofilm reactor is a standard method that has been deployed to study interactions between members of human microbiotas allowing studies to be completed during an extended period under conditions where nutrient availability, and washout of waste products are controlled. The objective of this work was to develop a robust in vitro biofilm-model system from a pooled saliva inoculum to study the development, reproducibility and stability of the oral microbiota. By employing deep sequencing of the variable regions of the 16S rRNA gene, we found that the CDC biofilm reactor could be used to efficiently cultivate microbiota containing all six major phyla previously identified as the core saliva microbiota. After an acclimatisation period, communities in each reactor stabilised. Replicate reactors were predominately populated by a shared core microbiota; variation between replicate reactors was primarily driven by shifts in abundance of shared operational taxonomic units. We conclude that the CDC biofilm reactor can be used to cultivate communities that replicate key features of the human oral cavity and is a useful tool to facilitate studies of the dynamics of these communities.


Asunto(s)
Microbiota , Biopelículas , Humanos , Boca , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados
6.
Occup Med (Lond) ; 71(2): 95-98, 2021 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-33585881

RESUMEN

BACKGROUND: It is recognized that healthcare workers (HCWs) are at high risk of contracting Covid-19. It is incumbent on occupational health staff to recognize potential symptoms of Covid-19 among HCWs. AIMS: The aims of the study were to describe the presenting symptoms of HCWs who developed Covid-19 in Ireland, and to estimate the odds of specific symptoms being associated with a positive Covid-19 polymerase chain reaction (PCR) result. METHODS: A retrospective chart review of all symptomatic HCWs who self-presented for Covid-19 testing in Cork from March to May 2020 was conducted. A sex-matched case-control study was carried out to compare presenting features among those who tested positive compared to those who tested negative. Univariate and multivariable-adjusted conditional logistic regression models were run using Stata 15.0 to identify the symptoms associated with positive Covid-19 swab results. RESULTS: Three hundred and six HCWs were included in the study; 102 cases and 204 controls. Common presenting features among cases were fever/chills (55%), cough (44%) and headache (35%). The symptoms which were significantly associated with a positive Covid-19 swab result were loss of taste/smell (adjusted odds ratio [aOR] 12.15, 95% confidence interval [CI] 1.36-108.79), myalgia (aOR 2.36, 95% 1.27-4.38), fatigue (aOR 2.31, 95% CI 1.12-4.74), headache (aOR 2.11, 95% CI 1.19-3.74) and fever/chills (aOR 1.88, 95% CI 1.12-3.15). CONCLUSIONS: Fever, fatigue, myalgia, loss of taste/smell and headache were associated with increased odds of a Covid-19 diagnosis among symptomatic self-referred HCWs compared with those had negative swab results. Testing criteria for HCWs should reflect the broad range of possible symptoms of Covid-19.


Asunto(s)
COVID-19/complicaciones , Personal de Salud , Salud Laboral , Pandemias , Adulto , COVID-19/diagnóstico , COVID-19/virología , Prueba de COVID-19 , Tos/diagnóstico , Tos/etiología , Fatiga/diagnóstico , Fatiga/etiología , Femenino , Fiebre/diagnóstico , Fiebre/etiología , Cefalea/diagnóstico , Cefalea/etiología , Humanos , Irlanda , Modelos Logísticos , Masculino , Persona de Mediana Edad , Mialgia/diagnóstico , Mialgia/etiología , Oportunidad Relativa , Trastornos del Olfato/diagnóstico , Trastornos del Olfato/etiología , Estudios Retrospectivos , SARS-CoV-2 , Trastornos del Gusto/diagnóstico , Trastornos del Gusto/etiología , Adulto Joven
7.
Br J Dermatol ; 182(1): 156-165, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31056744

RESUMEN

BACKGROUND: The updated American Joint Committee on Cancer (AJCC) staging criteria for melanoma remain unable to identify high-risk stage I tumour subsets. OBJECTIVES: To determine the utility of epidermal autophagy and beclin 1 regulator 1 (AMBRA1)/loricrin (AMLo) expression as a prognostic biomarker for AJCC stage I cutaneous melanoma. METHODS: Peritumoral AMBRA1 expression was evaluated in a retrospective discovery cohort of 76 AJCC stage I melanomas. AMLo expression was correlated with clinical outcomes up to 12 years in two independent powered, retrospective validation and qualification cohorts comprising 379 AJCC stage I melanomas. RESULTS: Decreased AMBRA1 expression in the epidermis overlying primary melanomas in a discovery cohort of 76 AJCC stage I tumours was associated with a 7-year disease-free survival (DFS) rate of 81·5% vs. 100% survival with maintained AMBRA1 (P < 0·081). Following an immunohistochemistry protocol for semi-quantitative analysis of AMLo, analysis was undertaken in validation (n = 218) and qualification cohorts (n = 161) of AJCC stage I melanomas. Combined cohort analysis revealed a DFS rate of 98·3% in the AMLo low-risk group (n = 239) vs. 85·4% in the AMLo high-risk cohort (n = 140; P < 0·001). Subcohort multivariate analysis revealed that an AMLo hazard ratio (HR) of 4·04 [95% confidence interval (CI) 1·69-9·66; P = 0·002] is a stronger predictor of DFS than Breslow depth (HR 2·97, 95% CI 0·93-9·56; P = 0·068) in stage IB patients. CONCLUSIONS: Loss of AMLo expression in the epidermis overlying primary AJCC stage I melanomas identifies high-risk tumour subsets independently of Breslow depth. What's already known about this topic? There is an unmet clinical need for biomarkers of early-stage melanoma. Autophagy and beclin 1 regulator 1 (AMBRA1) is a proautophagy regulatory protein with known roles in cell proliferation and differentiation, and is a known tumour suppressor. Loricrin is a marker of epidermal terminal differentiation. What does this study add? AMBRA1 has a functional role in keratinocyte/epidermal proliferation and differentiation. The combined decrease/loss of peritumoral AMBRA1 and loricrin is associated with a significantly increased risk of metastatic spread in American Joint Committee on Cancer (AJCC) stage I tumours vs. melanomas, in which peritumoral AMBRA1 and loricrin are maintained, independently of Breslow depth. What is the translational message? The integration of peritumoral epidermal AMBRA1/loricrin biomarker expression into melanoma care guidelines will facilitate more accurate, personalized risk stratification for patients with AJCC stage I melanomas, thereby facilitating stratification for appropriate follow-up and informing postdiagnostic investigations, including sentinel lymph node biopsy, ultimately resulting in improved disease outcomes and rationalization of healthcare costs.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Melanoma , Proteínas de la Membrana/genética , Neoplasias Cutáneas , Autofagia , Epidermis/patología , Humanos , Melanoma/patología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Estados Unidos
8.
Clin Exp Dermatol ; 45(1): 48-55, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31265150

RESUMEN

BACKGROUND: We conducted a re-audit of the surgical practice of UK dermatologists for the treatment of nonmelanoma skin cancer and examined changes with reference to our previous audit in 2014. The audit was supplemented by a detailed assessment of completeness of the histopathology reports for each tumour. METHODS: UK dermatologists collected data on 10 consecutive nonmicrographic excisions for basal cell carcinoma (BCC) and 5 for squamous cell carcinoma (SCC). Data were collected on site, preoperative diagnosis, histological diagnosis, proximity to previous scars, and histological deep and peripheral margins. RESULTS: In total, 222 responses were received from 135 centres, reporting on 3290 excisions. Excisions from the head and neck accounted for 56.7% of cases. Tumour diameter (mean ± SD) was 11.4 ± SD 7.1 mm (maximum size 100 mm) and 97% of cases were primary excisions. BCCs and SCCs respectively accounted for 65.7% and 26.8% of total cases. Of the suspected BCCs and SCCs, 95.8% and 80.4%, respectively, were confirmed histologically. All margins for any tumour were clear in 97.0% of cases, and complication rate in the audit was < 1%. Of the 2864 histology reports evaluated, only 706 (24.6%) contained all core data items; 95% of these were structure (synoptic) reports. Commonly omitted items were level of invasion, risk and T stage, which were absent from 35.7%, 64.2% and 44.1% of reports, respectively. CONCLUSIONS: Diagnostic accuracy and complete excision rates remain high. Complication rates may be under-reported owing to lack of follow-up. Histopathology reporting has a greater chance of being complete if reports are generated on a field-based platform (synoptic reporting).


Asunto(s)
Dermatólogos , Patólogos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Neoplasias Cutáneas/cirugía , Carcinoma Basocelular/cirugía , Carcinoma de Células Escamosas/cirugía , Auditoría Clínica , Procedimientos Quirúrgicos Dermatologicos/estadística & datos numéricos , Márgenes de Escisión , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología , Sociedades Médicas , Reino Unido
9.
HIV Med ; 20(2): 157-163, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30457205

RESUMEN

OBJECTIVES: HIV disproportionately affects men who have sex with men (MSM) in Ireland. The aim of this study was to improve understanding of HIV testing among MSM living in Ireland to inform prevention and testing initiatives. METHODS: We used data from the MSM Internet Survey Ireland 2015 (MISI 2015), a cross-sectional survey of MSM living in Ireland. We identified factors associated with never having tested for HIV using univariable and multivariable logistic regression. We identified preferred sites for future tests and examined the relationships between unmet HIV testing needs and socio-demographic groups. RESULTS: More than one-third (n = 1006; 36%) of MSM had never tested for HIV. Multivariable logistic regression showed that untested men were more likely to be aged 18-24 years, live outside Dublin, have a lower level of education, be born in Ireland, identify as bisexual, be out to fewer people, and not have had sex with a man in the previous 12 months. The same groups of men also had the least knowledge about HIV and were least confident in accessing an HIV test. Men who had never tested for HIV were more likely to prefer testing by their general practitioner (GP) or using home sampling HIV kits and less likely to prefer testing in a sexual health clinic. CONCLUSIONS: HIV prevention and testing programmes for MSM should be targeted towards younger men, those living outside Dublin and those with lower levels of education. We recommend increased promotion and availability of free HIV testing services in a range of clinical and nonclinical settings (including self-sampling and home testing).


Asunto(s)
Infecciones por VIH/diagnóstico , Disparidades en Atención de Salud/estadística & datos numéricos , Homosexualidad Masculina/estadística & datos numéricos , Adulto , Factores de Edad , Estudios Transversales , Promoción de la Salud , Humanos , Internet , Irlanda/epidemiología , Modelos Logísticos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Medición de Riesgo , Encuestas y Cuestionarios , Adulto Joven
10.
Arterioscler Thromb Vasc Biol ; 38(7): 1644-1655, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29880491

RESUMEN

OBJECTIVE: Inhibition of PCSK9 (proprotein convertase subtilisin/kexin type 9) and statins are known to lower plasma LDL (low-density lipoprotein)-cholesterol concentrations. However, the comparative effects of these treatments on the postprandial metabolism of TRLs (triglyceride-rich lipoproteins) remain to be investigated. APPROACH AND RESULTS: We performed a 2-by-2 factorial trial of the effects of 8 weeks of subcutaneous evolocumab (420 mg every 2 weeks) and atorvastatin (80 mg daily) on postprandial TRL metabolism in 80 healthy, normolipidemic men after ingestion of an oral fat load. We evaluated plasma total and incremental area under the curves for triglycerides, apo (apolipoprotein)B-48, and VLDL (very-LDL)-apoB-100. We also examined the kinetics of apoB-48 using intravenous D3-leucine administration, mass spectrometry, and multicompartmental modeling. Atorvastatin and evolocumab independently lowered postprandial VLDL-apoB-100 total area under the curves (P<0.001). Atorvastatin, but not evolocumab, reduced fasting plasma apoB-48, apoC-III, and angiopoietin-like 3 concentrations (P<0.01), as well as postprandial triglyceride and apoB-48 total area under the curves (P<0.001) and the incremental area under the curves for plasma triglycerides, apoB-48, and VLDL-apoB-100 (P<0.01). Atorvastatin also independently increased TRL apoB-48 fractional catabolic rate (P<0.001) and reduced the number of apoB-48-containing particles secreted in response to the fat load (P<0.01). In contrast, evolocumab did not significantly alter the kinetics of apoB-48. CONCLUSIONS: In healthy, normolipidemic men, atorvastatin decreased fasting and postprandial apoB-48 concentration by accelerating the catabolism of apoB-48 particles and reducing apoB-48 particle secretion in response to a fat load. Inhibition of PCSK9 with evolocumab had no significant effect on apoB-48 metabolism.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Anticolesterolemiantes/administración & dosificación , Atorvastatina/administración & dosificación , Grasas de la Dieta/sangre , Lipoproteínas/sangre , Inhibidores de PCSK9 , Inhibidores de Serina Proteinasa/administración & dosificación , Triglicéridos/sangre , Administración Oral , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales Humanizados , Apolipoproteína B-100/sangre , Apolipoproteína B-48/sangre , Apolipoproteína C-III/sangre , Grasas de la Dieta/administración & dosificación , Método Doble Ciego , Esquema de Medicación , Humanos , Inyecciones Subcutáneas , Lipoproteínas VLDL/sangre , Masculino , Persona de Mediana Edad , Periodo Posprandial , Proproteína Convertasa 9/metabolismo , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
11.
Arterioscler Thromb Vasc Biol ; 38(5): 1178-1190, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29449335

RESUMEN

OBJECTIVE: Bempedoic acid (BemA; ETC-1002) is a novel drug that targets hepatic ATP-citrate lyase to reduce cholesterol biosynthesis. In phase 2 studies, BemA lowers elevated low-density lipoprotein cholesterol (LDL-C) in hypercholesterolemic patients. In the present study, we tested the ability of BemA to decrease plasma cholesterol and LDL-C and attenuate atherosclerosis in a large animal model of familial hypercholesterolemia. APPROACH AND RESULTS: Gene targeting has been used to generate Yucatan miniature pigs heterozygous (LDLR+/-) or homozygous (LDLR-/-) for LDL receptor deficiency (ExeGen). LDLR+/- and LDLR-/- pigs were fed a high-fat, cholesterol-containing diet (34% kcal fat; 0.2% cholesterol) and orally administered placebo or BemA for 160 days. In LDLR+/- pigs, compared with placebo, BemA decreased plasma cholesterol and LDL-C up to 40% and 61%, respectively. In LDLR-/- pigs, in which plasma cholesterol and LDL-C were 5-fold higher than in LDLR+/- pigs, BemA decreased plasma cholesterol and LDL-C up to 27% and 29%, respectively. Plasma levels of triglycerides and high-density lipoprotein cholesterol, fasting glucose and insulin, and liver lipids were unaffected by treatment in either genotype. In the aorta of LDLR+/- pigs, BemA robustly attenuated en face raised lesion area (-58%) and left anterior descending coronary artery cross-sectional lesion area (-40%). In LDLR-/- pigs, in which lesions were substantially more advanced, BemA decreased aortic lesion area (-47%) and left anterior descending coronary artery lesion area (-48%). CONCLUSIONS: In a large animal model of LDLR deficiency and atherosclerosis, long-term treatment with BemA reduces LDL-C and attenuates the development of aortic and coronary atherosclerosis in both LDLR+/- and LDLR-/- miniature pigs.


Asunto(s)
Anticolesterolemiantes/farmacología , Enfermedades de la Aorta/prevención & control , Aterosclerosis/prevención & control , LDL-Colesterol/sangre , Enfermedad de la Arteria Coronaria/prevención & control , Ácidos Dicarboxílicos/farmacología , Ácidos Grasos/farmacología , Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Receptores de LDL/deficiencia , Animales , Animales Modificados Genéticamente , Anticolesterolemiantes/farmacocinética , Enfermedades de la Aorta/sangre , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/patología , Aterosclerosis/sangre , Aterosclerosis/genética , Aterosclerosis/patología , Biomarcadores/sangre , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/patología , Ácidos Dicarboxílicos/farmacocinética , Modelos Animales de Enfermedad , Regulación hacia Abajo , Ácidos Grasos/farmacocinética , Femenino , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Hiperlipoproteinemia Tipo II/sangre , Hiperlipoproteinemia Tipo II/genética , Masculino , Fenotipo , Placa Aterosclerótica , Receptores de LDL/genética , Porcinos , Porcinos Enanos
12.
Limnol Oceanogr ; 64(3): 1333-1346, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31741542

RESUMEN

Arsenic contamination of lakebed sediments is widespread due to a range of human activities, including herbicide application, waste disposal, mining, and smelter operations. The threat to aquatic ecosystems and human health is dependent on the degree of mobilization from sediments into overlying water columns and exposure of aquatic organisms. We undertook a mechanistic investigation of arsenic cycling in two impacted lakes within the Puget Sound region, a shallow weakly-stratified lake and a deep seasonally-stratified lake, with similar levels of lakebed arsenic contamination. We found that the processes that cycle arsenic between sediments and the water column differed greatly in shallow and deep lakes. In the shallow lake, seasonal temperature increases at the lakebed surface resulted in high porewater arsenic concentrations that drove larger diffusive fluxes of arsenic across the sediment-water interface compared to the deep, stratified lake where the lakebed remained ~10#x00B0;C cooler. Plankton in the shallow lake accumulated up to an order of magnitude more arsenic than plankton in the deep lake due to elevated aqueous arsenic concentrations in oxygenated waters and low phosphate: arsenate ratios in the shallow lake. As a result, strong arsenic mobilization from sediments in the shallow lake was countered by large arsenic sedimentation rates out of the water column driven by plankton settling.

13.
Eur Heart J ; 39(27): 2577-2585, 2018 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-29566128

RESUMEN

Aims: Lipoprotein(a) [Lp(a)], a low-density lipoprotein (LDL) particle covalently bound to apolipoprotein(a) [apo(a)], is a potentially potent heritable risk factor for cardiovascular disease. We investigated the mechanism whereby evolocumab, a monoclonal antibody against proprotein convertase subtilisin-kexin type 9 (PCSK9), lowers Lp(a). Methods and results: We studied the kinetics of Lp(a) particles in 63 healthy men, with plasma apo(a) concentration >5 nmol/L, participating in an 8-week factorial trial of the effects of evolocumab (420 mg every 2 weeks) and atorvastatin (80 mg daily) on lipoprotein metabolism. Lipoprotein(a)-apo(a) kinetics were studied using intravenous D3-leucine administration, mass spectrometry, and compartmental modelling; Lp(a)-apoB kinetics were also determined in 16 subjects randomly selected from the treatment groups. Evolocumab, but not atorvastatin, significantly decreased the plasma pool size of Lp(a)-apo(a) (-36%, P < 0.001 for main effect). As monotherapy, evolocumab significantly decreased the production of Lp(a)-apo(a) (-36%, P < 0.001). In contrast, in combination with atorvastatin, evolocumab significantly increased the fractional catabolism of Lp(a)-apo(a) (+59%, P < 0.001), but had no effect on the production of Lp(a)-apo(a). There was a highly significant association between the changes in the fractional catabolism of Lp(a)-apo(a) and Lp(a)-apoB in the substudy of 16 subjects (r = 0.966, P < 0.001). Conclusions: Evolocumab monotherapy lowered the plasma Lp(a) pool size by decreasing the production of Lp(a) particles. In combination with atorvastatin, evolocumab lowered the plasma Lp(a) pool size by accelerating the catabolism of Lp(a) particles. This dual mechanism may relate to an effect of PCSK9 inhibition on Lp(a)-apo(a) production and to marked up-regulation of LDL receptor activity on Lp(a) holoparticle clearance. Clinical Trial Registration Information: NCT02189837.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Anticolesterolemiantes/farmacología , Atorvastatina/farmacología , Lipoproteína(a)/efectos de los fármacos , Lipoproteína(a)/metabolismo , Inhibidores de PCSK9 , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales Humanizados , Humanos , Cinética , Lipoproteína(a)/sangre , Masculino , Persona de Mediana Edad , Adulto Joven
16.
Circulation ; 135(4): 338-351, 2017 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-27941065

RESUMEN

BACKGROUND: Monoclonal antibodies against proprotein convertase subtilisin kexin type 9 (PCSK9), such as evolocumab, lower plasma low-density lipoprotein (LDL)-cholesterol concentrations. Evolocumab is under investigation for its effects on cardiovascular outcomes in statin-treated, high-risk patients. The mechanism of action of PCSK9 monoclonal antibodies on lipoprotein metabolism remains to be fully evaluated. Stable isotope tracer kinetics can effectively elucidate the mode of action of new lipid-regulating pharmacotherapies. METHODS: We conducted a 2-by-2 factorial trial of the effects of atorvastatin (80 mg daily) and subcutaneous evolocumab (420 mg every 2 weeks) for 8 weeks on the plasma kinetics of very-low-density lipoprotein (VLDL)-apolipoprotein B-100 (apoB), intermediate-density lipoprotein-apoB, and LDL-apoB in 81 healthy, normolipidemic, nonobese men. The kinetics of apoB in these lipoproteins was studied using a stable isotope infusion of D3-leucine, gas chromatography/mass spectrometry, and multicompartmental modeling. RESULTS: Atorvastatin and evolocumab independently accelerated the fractional catabolism of VLDL-apoB (P<0.001 and P.032, respectively), intermediate-density lipoprotein-apoB (P=0.021 and P=.002, respectively), and LDL-apoB (P<0.001, both interventions). Evolocumab but not atorvastatin decreased the production rate of intermediate-density lipoprotein-apoB (P=0.043) and LDL-apoB (P<0.001), which contributed to the reduction in the plasma pool sizes of these lipoprotein particles. The reduction in LDL-apoB and LDL-cholesterol concentrations was significantly greater with combination versus either monotherapy (P<0.001). Whereas evolocumab but not atorvastatin lowered the concentration of free PCSK9, atorvastatin lowered the lathosterol/campesterol ratio (a measure of cholesterol synthesis/absorption) and apoC-III concentration. Both interventions decreased plasma apoE, but neither significantly altered lipoprotein lipase and cholesteryl ester protein mass or measures of insulin resistance. CONCLUSIONS: In healthy, normolipidemic subjects, evolocumab decreased the concentration of atherogenic lipoproteins, particularly LDL, by accelerating their catabolism. Reductions in intermediate-density lipoprotein and LDL production also contributed to the decrease in LDL particle concentration with evolocumab by a mechanism distinct from that of atorvastatin. These kinetic findings provide a metabolic basis for understanding the potential benefits of PCSK9 monoclonal antibodies incremental to statins in on-going clinical end point trials. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02189837.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Atorvastatina/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Atorvastatina/administración & dosificación , Método Doble Ciego , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Masculino , Persona de Mediana Edad , Adulto Joven
17.
J Surg Res ; 223: 155-164, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29433868

RESUMEN

BACKGROUND: Enteroid-derived tissue-engineered intestine (TEI) contains intestinal subepithelial myofibroblasts (ISEMFs) and smooth muscle cells (SMCs). However, these cell types are not present in the donor enteroids. We sought to determine the origin of these cell types and to quantify their importance in TEI development. MATERIALS AND METHODS: Crypts from pan-EGFP or LGR5-EGFP mice were used for enteroid culture and subsequent implantation for the production of TEI. TEI from pan-EGFP enteroids was labeled for smooth muscle alpha actin (SMA) to identify ISEMFs and SMCs and green fluorescent protein (GFP) to identify cells from pan-EGFP enteroids. Fluorescence in situ hybridization (FISH) for the Y chromosome was applied to TEI from male LGR5-EGFP enteroids implanted into female nonobese diabetic/severe combined immunodeficiency mice. To identify chemotactic effects of intestinal epithelium on ISEMFs, a Boyden chamber assay was performed. RESULTS: Immunofluorescence of TEI from pan-EGFP enteroids revealed GFP-positive epithelium with surrounding SMA positivity and no colocalization of the two. FISH of TEI from male LGR5-EGFP enteroids implanted into female nonobese diabetic/severe combined immunodeficiency mice revealed that only the epithelium was Y chromosome positive. Chemotactic assays demonstrated increased ISEMF migration in the presence of enteroids (983 ± 133) compared to that in the presence of either Matrigel alone (357 ± 36) or media alone (339 ± 24; P ≤ 0.05). CONCLUSIONS: Lack of GFP/SMA colocalization suggests that ISEMFs and SMCs are derived from host animals. This was confirmed by FISH which identified only epithelial cells as being male. All other cell types originated from host animals. The mechanism by which these cells are recruited is unknown; however, Boyden chamber assays indicate a direct chemotactic effect of intestinal epithelium on ISEMFs.


Asunto(s)
Mucosa Intestinal/citología , Intestinos/citología , Miocitos del Músculo Liso/citología , Miofibroblastos/citología , Ingeniería de Tejidos , Animales , Células Cultivadas , Quimiotaxis , Femenino , Proteínas Fluorescentes Verdes , Masculino , Ratones , Miocitos del Músculo Liso/fisiología , Miofibroblastos/fisiología
19.
Ecol Food Nutr ; 57(4): 261-281, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29923747

RESUMEN

In this case study, a formative evaluation was conducted for "Promoting Food Security and Healthy Lifestyles" pilot intervention at a Community-Based Organization in a marginalized neighborhood in Bedford-Stuyvesant in New York City. Utilizing a rigorous, theoretically grounded, and mixed methods approach, a survey was designed to encompass the social, environmental, and behavioral determinants of food insecurity and health promotion for Emergency Food Assistance System users. The final survey tested well for face and content validity and meets the criteria for internal reliability. This will aid to develop culturally tailored programs and policies for low-income, food insecure populations facing social and health disparities in this large urban neighborhood.


Asunto(s)
Dieta Saludable , Asistencia Alimentaria , Promoción de la Salud/métodos , Estilo de Vida Saludable , Encuestas Nutricionales , Salud Urbana , Adulto , Anciano , Competencia Cultural , Dieta Saludable/economía , Dieta Saludable/psicología , Salud de la Familia/economía , Femenino , Grupos Focales , Abastecimiento de Alimentos/economía , Humanos , Masculino , Persona de Mediana Edad , Ciudad de Nueva York , Estudios de Casos Organizacionales , Proyectos Piloto , Marginación Social/psicología , Factores Socioeconómicos , Estrés Psicológico/prevención & control , Salud Urbana/economía
20.
J Lipid Res ; 58(7): 1315-1324, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28392500

RESUMEN

Small dense LDL (sdLDL) has been reported to be more atherogenic than large buoyant LDL (lbLDL). We examined the metabolism and protein composition of sdLDL and lbLDL in six subjects with combined hyperlipidemia on placebo and rosuvastatin 40 mg/day. ApoB-100 kinetics in triglyceride-rich lipoproteins (TRLs), lbLDL (density [d] = 1.019-1.044 g/ml), and sdLDL (d = 1.044-1.063 g/ml) were determined in the fed state by using stable isotope tracers, mass spectrometry, and compartmental modeling. Compared with placebo, rosuvastatin decreased LDL cholesterol and apoB-100 levels in TRL, lbLDL, and sdLDL by significantly increasing the fractional catabolic rate of apoB-100 (TRL, +45%; lbLDL, +131%; and sdLDL, +97%), without a change in production. On placebo, 25% of TRL apoB-100 was catabolized directly, 37% was converted to lbLDL, and 38% went directly to sdLDL; rosuvastatin did not alter these distributions. During both phases, sdLDL apoB-100 was catabolized more slowly than lbLDL apoB-100 (P < 0.01). Proteomic analysis indicated that rosuvastatin decreased apoC-III and apoM content within the density range of lbLDL (P < 0.05). In our view, sdLDL is more atherogenic than lbLDL because of its longer plasma residence time, potentially resulting in more particle oxidation, modification, and reduction in size, with increased arterial wall uptake. Rosuvastatin enhances the catabolism of apoB-100 in both lbLDL and sdLDL.


Asunto(s)
LDL-Colesterol/química , LDL-Colesterol/metabolismo , Hiperlipidemia Familiar Combinada/tratamiento farmacológico , Hiperlipidemia Familiar Combinada/metabolismo , Tamaño de la Partícula , Proteómica , Rosuvastatina Cálcica/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rosuvastatina Cálcica/uso terapéutico
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