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1.
Environ Health Perspect ; 129(6): 67005, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34160246

RESUMEN

BACKGROUND: In utero exposure to heavy metals lead (Pb), mercury (Hg), and cadmium (Cd) may be associated with higher childhood blood pressure (BP), whereas trace elements selenium (Se) and manganese (Mn) may have protective antioxidant effects that modify metal-BP associations. OBJECTIVES: We examined the individual and joint effects of in utero exposure to Pb, Hg, Cd, Se, and Mn on childhood BP. METHODS: We used data from the Boston Birth Cohort (enrolled 2002-2013). We measured heavy metals and trace elements in maternal red blood cells collected 24-72 h after delivery. We calculated child BP percentile per the 2017 American Academy of Pediatrics Clinical Practice Guideline. We used linear regression models to estimate the association of each metal, and Bayesian kernel machine regression (BKMR) to examine metal coexposures, with child BP between 3 to 15 years of age. RESULTS: Our analytic sample comprised 1,194 mother-infant pairs (61% non-Hispanic Black, 20% Hispanic). Hg and Pb were not associated with child systolic BP (SBP). Se and Mn were inversely associated with child SBP percentiles, which, on average, were 6.23 points lower with a doubling of Se (95% CI: -11.51, -0.96) and 2.62 points lower with a doubling of Mn (95% CI: -5.20, -0.04). BKMR models showed similar results. Although Cd was not associated with child SBP overall, the inverse association between Mn and child SBP was stronger at higher levels of Cd (p-interaction=0.04). Consistent with this finding, in utero exposure to cigarette smoke modified the Mn-child SBP association. Among children whose mothers smoked during pregnancy, a doubling of Mn was associated with a 10.09-point reduction in SBP percentile (95% CI: -18.03, -2.15), compared with a 1.49-point reduction (95% CI: -4.21, 1.24) in children whose mothers did not smoke during pregnancy (p-interaction=0.08). CONCLUSION: Se and Mn concentrations in maternal red blood cells collected 24-72 h after delivery were associated with lower child SBP at 3 to 15 years of age. There was an interaction between Mn and Cd on child SBP, whereby the protective association of Mn on child SBP was stronger among mothers who had higher Cd. The association of Mn and child SBP was also modified by maternal cigarette smoking-a source of Cd-during pregnancy. Optimizing in utero Se levels, as well as Mn levels in women who had high Cd or smoked during pregnancy, may protect offspring from developing high BP during childhood. https://doi.org/10.1289/EHP8325.


Asunto(s)
Metales Pesados , Selenio , Oligoelementos , Teorema de Bayes , Presión Sanguínea , Niño , Femenino , Humanos , Metales Pesados/toxicidad , Embarazo
2.
J Nat Prod ; 79(11): 2924-2932, 2016 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-27933899

RESUMEN

A phytochemical investigation to obtain new NO inhibitors resulted in the identification of six new (1-6) and four known (7-10) terpenoids from Salvia plebeia. Compounds 1 and 2 are new diterpenoids, 3-5 are new meroditerpenoids, 6-9 are sesquiterpenoids, and 10 is a known meroditerpenoid. The structures of these isolates were determined by routine NMR experiments and X-ray diffraction, as well as the electronic circular dichroism spectra. Compounds 1-4 are diterpenoids carrying an oxygen bridge, and 6 is a rare copane-type sesquiterpenoid with a bridged tricyclic framework. The isolates inhibited NO generation induced by lipopolysaccharide in BV-2 cells. The possible mechanism of NO inhibition of some bioactive compounds was also investigated using molecular docking, which revealed interactions of bioactive compounds with the iNOS protein.


Asunto(s)
Diterpenos/aislamiento & purificación , Diterpenos/farmacología , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Salvia/química , Cristalografía por Rayos X , Diterpenos/química , Medicamentos Herbarios Chinos/química , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Conformación Molecular , Simulación del Acoplamiento Molecular , Estructura Molecular , Óxido Nítrico/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología
3.
J Nat Prod ; 78(11): 2800-7, 2015 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-26558315

RESUMEN

Two new ent-pimarane (1 and 2), eight new ent-abietane (3-10) diterpenoids, and eight known analogues (11-18) were isolated from the whole plants of Chloranthus henryi. The absolute configuration of 1 was determined on the basis of single-crystal X-ray diffraction data. Compound 8 represents a class of rare naturally occurring C-14 norabietanes, and compounds 9 and 10 feature rare 13,14-seco-abietane skeletons. Compounds 5, 12, 13, and 15 inhibited the yeast-to-hyphae transition of Candida albicans with IC50 values between 97.3 and 738.7 µM.


Asunto(s)
Abietanos/aislamiento & purificación , Diterpenos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Magnoliopsida/química , Abietanos/química , Abietanos/farmacología , Asteraceae/química , Candida albicans/efectos de los fármacos , Cristalografía por Rayos X , Diterpenos/química , Diterpenos/farmacología , Diterpenos de Tipo Kaurano/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Concentración 50 Inhibidora , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular
4.
J Agric Food Chem ; 63(41): 9006-11, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26429144

RESUMEN

Inula japonica belongs to the family Asteraceae, and its flowers have been used as dietary supplements and health tea in China. The study aimed to identify the bioactive components with the antiproliferative property. Ten 1,10-seco-eudesmanolide derivatives, including four new compounds (1-4), were isolated from the flowers of I. japonica. Their structures were established on the basis of the interpretation of spectroscopic data and electronic circular dichroism (ECD) calculations. All of these isolates were evaluated for their antiproliferative activities against MCF-7 and MDA-MB-231 human breast cancer cells. Compound 4 possessed the most potent effects, with the IC50 values of 0.20 ± 0.04 and 6.22 ± 1.30 µM against MCF-7 and MDA-MB-231 cells, respectively. The present investigation indicated that eudesmanolide derivatives from the flowers of I. japonica, especially compound 4, might be used as potential antitumor chemotherapy agent candidates.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Inhibidores de Crecimiento/química , Inhibidores de Crecimiento/farmacología , Inula/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Línea Celular Tumoral , Medicamentos Herbarios Chinos/aislamiento & purificación , Flores/química , Inhibidores de Crecimiento/aislamiento & purificación , Humanos , Estructura Molecular , Sesquiterpenos/aislamiento & purificación
5.
J Agric Food Chem ; 62(45): 10945-53, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25331421

RESUMEN

Celastrus orbiculatus is an insecticidal plant belonging to the Celastraceae family. In this survey on the secondary metabolites of plants for obtaining bioactive substances to serve agriculture, the chemical constituents of the fruits of C. orbiculatus were investigated. This phytochemical investigation resulted in the isolation of nine new and one known sesquiterpene. Their structures, especially the complicated stereochemical features, were elucidated on the basis of extensive NMR spectroscopic data analyses, time-dependent density functional theory CD calculations, and the CD exciton chirality method. Biological screenings disclosed that these sesquiterpenes showed antifungal activities against six phytopathogenic fungi. The results of our phytochemical investigation further disclosed the chemical components of C. orbiculatus, and biological screening implied that it may be potentially useful to protect crops against phytopathogenic fungi and the bioactive compounds may be regarded as candidate agents of antifungal agrochemicals for crop protection products.


Asunto(s)
Antifúngicos/farmacología , Celastrus/química , Hongos/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Frutas/química , Hongos/fisiología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación
6.
J Nat Prod ; 77(10): 2182-9, 2014 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-25286284

RESUMEN

Eight new clerodane diterpenes, balanspenes A-H (1-8), along with two known analogues (9 and 10), were isolated from the twigs of Casearia balansae. The structures of 1-8 were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analysis, and the absolute configurations of compounds 1, 4, and 7 were confirmed by comparing their experimental CD spectra with those calculated by the time-dependent density functional theory method. Compounds 4-7, 9, and 10 were found to possess the property of being able to stimulate NGF-mediated neurite outgrowth from PC12 cells.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Casearia/química , Diterpenos de Tipo Clerodano/aislamiento & purificación , Diterpenos de Tipo Clerodano/farmacología , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Animales , Antineoplásicos Fitogénicos/química , Dicroismo Circular , Diterpenos de Tipo Clerodano/química , Ensayos de Selección de Medicamentos Antitumorales , Medicamentos Herbarios Chinos/química , Estructura Molecular , Factor de Crecimiento Nervioso/farmacología , Neuritas/efectos de los fármacos , Resonancia Magnética Nuclear Biomolecular , Células PC12 , Tallos de la Planta/química , Ratas
7.
J Agric Food Chem ; 62(38): 9362-7, 2014 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-25188451

RESUMEN

Petasites tatewakianus is an edible plant belonging to the family Compositae. In our continuous search for NO inhibitors, which may be useful for the development of anti-inflammatory agents, the chemical constituents of the leaves of the edible plant P. tatewakianus were investigated. This phytochemical investigation led to the isolation of 3 new (1-3) and 10 known (4-13) sesquiterpenes and 2 other types of known compounds (14 and 15). Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analyses, and the absolute configurations of compounds 1 and 3 were confirmed by comparing their experimental CD spectra with those calculated by the time-dependent density functional theory (TDDFT) method. The following biological studies disclosed that these isolated compounds showed inhibitory activities on LPS-induced NO production in murine microglial BV-2 cells. The results of our phytochemical investigation, including two new bakkenolide sesquiterpenes (1 and 2), one new sesquiterpene with an unusual carbon skeleton (3), and the first report of compounds 5-7 and 10-15 from this species, further revealed the chemical composition of P. tatewakianus as an edible plant, and the biological studies implied that P. tatewakianus, containing bioactive substances with the inhibitory activities of NO production, was potentially beneficial to human health.


Asunto(s)
Óxido Nítrico/antagonistas & inhibidores , Petasites/química , Extractos Vegetales/química , Plantas Comestibles/química , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Línea Celular , Ratones , Microglía/efectos de los fármacos , Microglía/inmunología , Estructura Molecular , Óxido Nítrico/inmunología , Extractos Vegetales/aislamiento & purificación
8.
J Agric Food Chem ; 62(20): 4784-8, 2014 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-24801989

RESUMEN

The inhibitory reagents to inhibit the activation of microglial cells may be potentially useful for the treatment of neurodegenerative diseases. The leaves of the plant Laurus nobilis belonging to the family Lauraceae, namely, bay leaves, have been used as a popular spice, and their extract showed moderate inhibition on microglial activation. A further phytochemical investigation of the leaves led to the isolation of two new (1, 2) and eight known (3-10) sesquiterpenes. Their structures were elucidated on the basis of extensive 1D and 2D NMR (HMQC, HMBC, (1)H-(1)H COSY, and NOESY) spectroscopic data analyses and Chem3D modeling. The following biological studies disclosed that these isolated compounds showed inhibitory activities on LPS-induced microglial activation. The results of our phytochemical investigation, including two new sesquiterpenes (1 and 2) and the first report of two compounds (3 and 4) from this species, further revealed the chemical composition of bay leaves as a popular spice, and the biological studies implied that bay leaves, containing bioactive substances with the inhibition of microglial activation, were potentially beneficial to human health.


Asunto(s)
Laurus/química , Microglía/efectos de los fármacos , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Animales , Humanos , Ratones , Microglía/fisiología , Estructura Molecular , Enfermedades Neurodegenerativas/fisiopatología , Extractos Vegetales/química , Hojas de la Planta/química , Sesquiterpenos/química
9.
Fitoterapia ; 95: 229-33, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24685507

RESUMEN

Nerve growth factor (NGF) and analog reagents to promote the neurite outgrowth of nerve cells against the neuron degeneration are expected to be potentially useful for the medical treatment of Alzheimer's disease. In our focus on the discovery of bioactive diterpenes, we investigated the chemical constituents of the plant Croton yanhuii. This investigation led to the isolation and identification of two novel clerodane diterpenes (1 and 2). Their structures were elucidated on the basis of extensive 1D and 2D NMR (COSY, HMQC, HMBC, and NOESY) and mass (ESIMS and HR-ESIMS) spectroscopic data analyses. Further biological screenings showed that both of the compounds enhanced NGF-mediated neurite outgrowth from PC12 cells.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Croton/química , Diterpenos de Tipo Clerodano/aislamiento & purificación , Neuritas/efectos de los fármacos , Animales , Diterpenos de Tipo Clerodano/química , Diterpenos de Tipo Clerodano/farmacología , Diterpenos de Tipo Clerodano/uso terapéutico , Sinergismo Farmacológico , Espectroscopía de Resonancia Magnética , Estructura Molecular , Factor de Crecimiento Nervioso/metabolismo , Células PC12 , Plantas Medicinales , Ratas
10.
Fitoterapia ; 95: 133-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24641945

RESUMEN

Three new jatrophane diterpenes (1-3), an unreported spectroscopic data jatrophane diterpenene (4), and nine known analogues (5-13) have been isolated from the whole plants of Euphorbia helioscopia. Their structures were established by detailed spectroscopic data analyses (IR, ESIMS, HR-ESIMS, and 1D and 2D NMR), and the structure of 1 was confirmed by X-ray crystallography. The diterpenes showed inhibitory activities on LPS-induced NO production in murine microglial BV-2 cells.


Asunto(s)
Diterpenos/farmacología , Euphorbia/química , Óxido Nítrico/metabolismo , Extractos Vegetales/farmacología , Animales , Línea Celular , Cristalografía por Rayos X , Diterpenos/química , Diterpenos/aislamiento & purificación , Lipopolisacáridos/metabolismo , Espectroscopía de Resonancia Magnética , Medicina Tradicional China , Ratones , Microglía/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales
11.
Food Chem ; 141(3): 2075-82, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23870930

RESUMEN

Neuroprotective reagents to protect the nerve cells against oxidative stress and other damages are potentially effective for the medical treatment of Parkinson's disease. Petasites japonicus, a wild vegetable, belongs to the family Compositae and its extract has shown the neuroprotective effects. A further phytochemical investigation of P. japonicus for neuroprotective substances led to the isolation of eight new (1-8) and two known (9 and 10) sesquiterpenes. Their structures were elucidated on the basis of extensive 1D and 2D NMR (HMQC, HMBC, (1)H-(1)H COSY, and NOESY) spectroscopic data analyses, and the structure of 1 was confirmed by X-ray crystallography. The neuroprotective activities of these sesquiterpenes were evaluated against cobalt chloride (CoCl2)-induced neuronal cell death in human dopaminergic SH-SY5Y cells. Five compounds showed a neuroprotective activity.


Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Petasites/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Línea Celular , Medicamentos Herbarios Chinos/aislamiento & purificación , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Sesquiterpenos/aislamiento & purificación
12.
Cancer Immunol Immunother ; 58(5): 737-48, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-18815785

RESUMEN

Current therapeutic approaches to treatment of patients with bulky cervical cancer are based on conventional in situ ablative modalities including cisplatin-based chemotherapy and radiation therapy. The 5-year survival of patients with nonresectable disease is dismal. Because over 99% of squamous cervical cancer is caused by persistent infection with an oncogenic strain of human papillomavirus (HPV), particularly type 16 and viral oncoproteins E6 and E7 are functionally required for disease initiation and persistence, HPV-targeted immune strategies present a compelling opportunity in which to demonstrate proof of principle. Sublethal doses of radiation and chemotherapeutic agents have been shown to have synergistic effect in combination with either vaccination against cancer-specific antigens, or with passive transfer of tumor-specific cytotoxic T lymphocytes (CTLs). Here, we explored the combination of low-dose radiation therapy with DNA vaccination with calreticulin (CRT) linked to the mutated form of HPV-16 E7 antigen (E7(detox)), CRT/E7(detox) in the treatment of E7-expressing TC-1 tumors. We observed that TC-1 tumor-bearing mice treated with radiotherapy combined with CRT/E7(detox) DNA vaccination generated significant therapeutic antitumor effects and the highest frequency of E7-specific CD8(+) T cells in the tumors and spleens of treated mice. Furthermore, treatment with radiotherapy was shown to render the TC-1 tumor cells more susceptible to lysis by E7-specific CTLs. In addition, we observed that treatment with radiotherapy during the second DNA vaccination generated the highest frequency of E7-specific CD8(+) T cells in the tumors and spleens of TC-1 tumor-bearing mice. Finally, TC-1 tumor-bearing mice treated with the chemotherapy in combination with radiation and CRT/E7(detox) DNA vaccination generate significantly enhanced therapeutic antitumor effects. The clinical implications of the study are discussed.


Asunto(s)
Inmunoterapia Activa , Neoplasias Experimentales/terapia , Vacunas contra Papillomavirus/uso terapéutico , Radioterapia Adyuvante/métodos , Linfocitos T Citotóxicos/inmunología , Vacunas de ADN/uso terapéutico , Animales , Apoptosis , Calreticulina/genética , Calreticulina/inmunología , Línea Celular Transformada/inmunología , Línea Celular Transformada/trasplante , Transformación Celular Viral , Terapia Combinada , Citocinas/análisis , Modelos Animales de Enfermedad , Femenino , Pulmón , Ratones , Ratones Endogámicos C57BL , Neoplasias Experimentales/inmunología , Neoplasias Experimentales/radioterapia , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/inmunología , Proteínas E7 de Papillomavirus , Dosificación Radioterapéutica , Proteínas Recombinantes de Fusión/inmunología , Neoplasias del Cuello Uterino
13.
Lifetime Data Anal ; 11(1): 61-79, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15747590

RESUMEN

Clustered failure time data are commonly encountered in biomedical research where the study subjects from the same cluster (e.g., family) share the common genetic and/or environmental factors such that the failure times within the same cluster are correlated. Two approaches that are commonly used to account for the intra-cluster association are frailty models and marginal models. In this paper, we study the marginal proportional hazards model, where the structure of dependence between individuals within a cluster is unspecified. An estimation procedure is developed based on a pseudo-likelihood approach, and a risk set sampling method is proposed for the formulation of the pseudo-likelihood. The asymptotic properties of the proposed estimators are studied, and the related issues regarding the statistical efficiencies are discussed. The performances of the proposed estimator are demonstrated by the simulation studies. A data example from a child vitamin A supplementation trial in Nepal (Nepal Nutrition Intervention Project-Sarlahi, or NNIPS) is used to illustrate this methodology.


Asunto(s)
Análisis por Conglomerados , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Deficiencia de Vitamina A/mortalidad , Vitamina A/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Funciones de Verosimilitud , Masculino , Nepal , Ensayos Clínicos Controlados Aleatorios como Asunto , Sensibilidad y Especificidad
14.
Biometrics ; 58(4): 764-72, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12495130

RESUMEN

Cohort case-control design is an efficient and economical design to study risk factors for disease incidence or mortality in a large cohort. In the last few decades, a variety of cohort case-control designs have been developed and theoretically justified. These designs have been exclusively applied to the analysis of univariate failure-time data. In this work, a cohort case-control design adapted to multivariate failure-time data is developed. A risk set sampling method is proposed to sample controls from nonfailures in a large cohort for each case matched by failure time. This method leads to a pseudolikelihood approach for the estimation of regression parameters in the marginal proportional hazards model (Cox, 1972, Journal of the Royal Statistical Society, Series B 34, 187-220), where the correlation structure between individuals within a cluster is left unspecified. The performance of the proposed estimator is demonstrated by simulation studies. A bootstrap method is proposed for inferential purposes. This methodology is illustrated by a data example from a child vitamin A supplementation trial in Nepal (Nepal Nutrition Intervention Project-Sarlahi, or NNIPS).


Asunto(s)
Estudios de Casos y Controles , Estudios de Cohortes , Modelos de Riesgos Proporcionales , Preescolar , Análisis por Conglomerados , Simulación por Computador , Femenino , Humanos , Lactante , Mortalidad Infantil , Funciones de Verosimilitud , Masculino , Análisis Multivariante , Factores de Riesgo , Vitamina A/administración & dosificación
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