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1.
Huan Jing Ke Xue ; 44(9): 4954-4964, 2023 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-37699813

RESUMEN

The typical river-lake ecotone (tail end area) of Poyang Lake, which is a sensitive area and prone to outbreaks of cyanobacteria bloom, is vulnerable to frequent human activities. To explore the diversity of phytoplankton community structure and the relevant driving mechanism in the typical river lake junction area of Poyang Lake, the water quality and phytoplankton at seven sampling points in the typical river lake junction area of Poyang Lake, at six sampling points in the middle section of Poyang Lake River, and at one sampling point in the main lake area were investigated in the field from 2019 to 2020 (dry season), April (flood season), July (wet season), and October (recession period). The results showed that there were seven phyla and 64 genera of phytoplankton in the typical river-lake ecotone of Poyang Lake, and the biomass and relative abundance of phytoplankton were dominated by diatoms and cyanobacteria. The biomass and abundance in the east of the typical river-lake ecotone of Poyang Lake were generally higher than those in the west, and the biomass and abundance in the river-lake ecotone were higher than those in the middle of the river. The dominant degree of cyanobacteria in the lake area and the river-lake ecotone was large, and the dominant degree of diatoms in the middle section of the river was large. The Monte Carlo test results showed that total nitrogen (TN), total phosphorus (TP), orthophosphate phosphorus (PO43--P), water depth (WD), water temperature (WT), and transparency (SD) were significantly related environmental factors affecting the distribution of the phytoplankton community. Redundancy analysis results showed that the typical river-lake ecotone in the west of Poyang Lake was highly affected by the hydration factors (TN, TP, and PO43--P), and the hydrological factors (WT, WD, and SD) in the typical river-lake ecotone in the east were highly significant. The impact factors of phytoplankton in the typical river-lake ecotone of Poyang Lake were seasonal, being greatly affected by hydration factors in winter and hydrological factors in summer.


Asunto(s)
Diatomeas , Fitoplancton , Humanos , Ríos , Biomasa , Nitrógeno , Fósforo
2.
Healthcare (Basel) ; 9(8)2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34442198

RESUMEN

Despite campaigns to increase public awareness of stroke symptoms by advocating FAST (Face-Arms-Speech-Time), some stroke patients still show delays in the recognition of and response to stroke symptoms and miss the golden first 4.5 h to receive rt-PA (recombinant tissue plasminogen activator) treatment. The aim of this study was to explore how acute ischemic stroke patients with prehospital delay seek help and undergo the decision process before arriving at the hospital. A qualitative approach using a grounded theory was applied. There were 24 ischemic stroke patients recruited by purposive sampling. Our main findings were: "Hesitating and puzzling" was the core category to describe and guide the process of acute ischemic stroke patients with prehospital delay. During the process, "Awareness the sudden change of physical sensation and/or function" was the antecedent category. In the prehospital delay experience, the following five interaction categories were identified: (1) "Self-judgment and interpretation according to previous experience," (2) "Puzzling and doubting-it may only be a minor problem," (3) "Self-treatment or seeking medical attention nearby," (4) "Unexpected symptoms getting worse" needing immediate advanced medical help and (5) "Rushing to ER with different transportation-self-alerting that serious disease is coming." Eventually, the patients "Regret to delay seeking treatment and become a disable person." The process of prehospital delay provides some hidden cues for patients to increase their knowledge about strokes. The study emphasizes the importance of educating community residents about identifying stroke symptoms, breaking the myth of folk therapy, and seeking medical attention immediately. These results will assist healthcare providers by offering references for designing patient-centric educational strategies for preventing stroke prehospital delay to improve the quality of stroke medical care.

3.
Molecules ; 26(13)2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34209270

RESUMEN

Resveratrol butyrate esters (RBE) are derivatives of resveratrol (RSV) and butyric acid and exhibit biological activity similar to that of RSV but with higher bioavailability. The aim of this study was designed as an animal experiment to explore the effects of RBE on the serum biochemistry, and fat deposits in the offspring rats exposed to bisphenol A (BPA), along with the growth and decline of gut microbiota. We constructed an animal model of perinatal Bisphenol A (BPA) exposure to observe the effects of RBE supplementation on obesity, blood lipids, and intestinal microbiota in female offspring rats. Perinatal exposure to BPA led to weight gain, lipid accumulation, high levels of blood lipids, and deterioration of intestinal microbiota in female offspring rats. RBE supplementation reduced the weight gain and lipid accumulation caused by BPA, optimised the levels of blood lipids, significantly reduced the Firmicutes/Bacteroidetes (F/B) ratio, and increased and decreased the abundance of S24-7 and Lactobacillus, respectively. The analysis of faecal short-chain fatty acid (SCFA) levels revealed that BPA exposure increased the faecal concentration of acetate, which could be reduced via RBE supplementation. However, the faecal concentrations of propionate and butyrate were not only significantly lower than that of acetate, but also did not significantly change in response to BPA exposure or RBE supplementation. Hence, RBE can suppress BPA-induced obesity in female offspring rats, and it demonstrates excellent modulatory activity on intestinal microbiota, with potential applications in perinatological research.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Ácido Butírico/farmacología , Obesidad , Fenoles/toxicidad , Efectos Tardíos de la Exposición Prenatal , Resveratrol/farmacología , Animales , Ácidos Grasos Volátiles/metabolismo , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Obesidad/inducido químicamente , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/tratamiento farmacológico , Efectos Tardíos de la Exposición Prenatal/metabolismo , Ratas , Ratas Sprague-Dawley
4.
Antioxidants (Basel) ; 10(3)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33801821

RESUMEN

To expand the applications and enhance the stability and bioactivity of resveratrol (RE), and to simultaneously include the potential health benefits of short chain fatty acids (SCFA) esters of RE were prepared by Steglich reactions with acetic, propionic, and butyric acids, respectively. RE and the esterified RE-SCFA products (including RAE, RPE, and RBE) were analyzed using nuclear magnetic resonance (NMR), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis (DTA), and liquid chromatography-mass spectrometry (LC-MS). The FTIR and 13C NMR spectra of the esterified products included ester-characteristic peaks at 1751 cm-1 and 171 ppm, respectively. Moreover, the peaks in the range of 1700 to 1600 cm-1 in the FTIR spectra of the esterified products indicated that the esterification of RE-SCFA was successful. The TGA results revealed that the RE-SCFA esters decomposed at lower temperatures than RE. The peaks in the LC-MS profiles of the esterified products indicated the formation of mono- and diesters, and the calculated monoester synthesis rates ranged between 45.81 and 49.64%. The RE esters inhibited the Cu2+-induced low-density lipoprotein oxidation reaction, exhibited antioxidant activity in bulk oil, and effectively inhibited the hydroxyl radical-induced DNA scission. Moreover, the RE-SCFA esters had better hydrogen peroxide scavenging activity than RE. Our results are the first in the literature to successfully including short chain fatty acids in the esters of resveratrol, and the products could be used as a functional food ingredient in processed foods or can be used as dietary supplements to promote health.

5.
Molecules ; 25(18)2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32937766

RESUMEN

To facilitate broad applications and enhance bioactivity, resveratrol was esterified to resveratrol butyrate esters (RBE). Esterification with butyric acid was conducted by the Steglich esterification method at room temperature with N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide (EDC) and 4-dimethyl aminopyridine (DMAP). Our experiments demonstrated the synthesis of RBE through EDC- and DMAP-facilitated esterification was successful and that the FTIR spectra of RBE revealed absorption (1751 cm-1) in the ester region. 13C-NMR spectrum of RBE showed a peak at 171 ppm corresponding to the ester group and peaks between 1700 and 1600 cm-1 in the FTIR spectra. RBE treatment (25 or 50 µM) decreased oleic acid-induced lipid accumulation in HepG2 cells. This effect was stronger than that of resveratrol and mediated through the downregulation of p-ACC and SREBP-2 expression. This is the first study demonstrating RBE could be synthesized by the Steglich method and that resulting RBE could inhibit lipid accumulation in HepG2 cells. These results suggest that RBE could potentially serve as functional food ingredients and supplements for health promotion.


Asunto(s)
Ácido Butírico/síntesis química , Ésteres/síntesis química , Hígado/efectos de los fármacos , Hígado/metabolismo , Resveratrol/síntesis química , Resveratrol/farmacología , Acetil-CoA Carboxilasa/metabolismo , Carbodiimidas/química , Técnicas de Cultivo de Célula , Regulación hacia Abajo , Esterificación , Células Hep G2 , Humanos , Lípidos/química , Espectroscopía de Resonancia Magnética , Piridinas/química , Espectroscopía Infrarroja por Transformada de Fourier , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Termogravimetría
6.
BMC Cardiovasc Disord ; 17(1): 115, 2017 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-28482853

RESUMEN

BACKGROUND: Eosinophilic myocarditis encompasses a variety of etiologies and the prognosis varies. For patients with a hypersensitive response to medications, high-dose corticosteroids and discontinuation of culprit medications are the main treatments. CASE PRESENTATION: We reported a young man with biopsy-proven eosinophilic myocarditis which was possibly induced by Chinese herbal medicine. His heart failure and left ventricular hypertrophy improved soon after low-dose corticosteroid. CONCLUSION: Low-dose corticosteroid may be effective in selected patients with eosinophilic myocarditis. Early echocardiographic follow-up is mandatory for evaluation of the clinical response.


Asunto(s)
Corticoesteroides/administración & dosificación , Medicamentos Herbarios Chinos/efectos adversos , Eosinofilia/tratamiento farmacológico , Miocarditis/tratamiento farmacológico , Prednisolona/administración & dosificación , Enfermedad Aguda , Adulto , Biopsia , Ecocardiografía , Eosinofilia/inducido químicamente , Eosinofilia/diagnóstico , Eosinofilia/inmunología , Insuficiencia Cardíaca/etiología , Humanos , Hipertrofia Ventricular Izquierda/etiología , Masculino , Miocarditis/inducido químicamente , Miocarditis/diagnóstico , Miocarditis/inmunología , Inducción de Remisión , Factores de Tiempo , Resultado del Tratamiento
7.
Int J Radiat Oncol Biol Phys ; 96(2): 313-317, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27496390

RESUMEN

OBJECTIVE: To determine whether the distance between a prostate cancer patient's home and treatment facility was related to the choice of treatment received among those opting for surgery or radiation. METHODS AND MATERIALS: We identified 222,804 patients diagnosed with National Comprehensive Cancer Network low-, intermediate-, or high-risk N0M0 prostate cancer and treated with local therapy (surgery or radiation alone, with or without hormone therapy) using the National Cancer Database. We used multivariable logistic regression to determine whether the choice of radiation therapy vs radical prostatectomy varied by distance among patients living in rural and urban areas. Analyses were adjusted for geographic location within the United States, age, race, Charlson/Deyo comorbidity score, year of diagnosis, income quartile, education quartile, Gleason score, prostate-specific antigen level, and T stage. RESULTS: Patients living in urban or rural areas were less likely to receive radiation compared with surgery if they lived farther from the treatment facility. Among urban patients living ≤5 miles from the treatment facility, 53.3% received radiation, compared with 47.0%, 43.6%, and 33.8% of those living 5 to 10, 10 to 15, or >15 miles away, respectively (P<.001 in all cases). Similarly, rural patients were less likely to receive radiation the farther they lived from the treatment facility (≤25 miles: 62.3%; 25-50 miles: 55.5%; 50-75 miles: 38.4%; >75 miles: 23.8%; P<.05 in all cases). These trends were also present when each risk group was analyzed separately. CONCLUSION: Patients with prostate cancer in both urban and rural settings were less likely to receive radiation therapy rather than surgery the farther away they lived from a treatment center. These findings raise the possibility that the geographic availability of radiation treatment centers may be an important determinant of whether patients are able to choose radiation rather than surgery for localized prostate cancer.


Asunto(s)
Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Prioridad del Paciente/estadística & datos numéricos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/terapia , Población Rural/estadística & datos numéricos , Viaje/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Toma de Decisiones Clínicas/métodos , Geografía , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Prostatectomía , Radioterapia , Estados Unidos/epidemiología
8.
Brachytherapy ; 15(6): 695-700, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27528590

RESUMEN

PURPOSE: Androgen deprivation therapy (ADT) has been shown to improve survival for men with unfavorable-risk prostate cancer (PCa). We investigated the utilization and factors associated with the omission of ADT in radiation-managed high-risk PCa. METHODS AND MATERIALS: We used the National Cancer Database to identify men with National Comprehensive Cancer Network high-risk PCa treated with external beam radiation therapy (EBRT) with or without brachytherapy boost from 2004 to 2012. Multivariable logistic regression adjusting for clinical and sociodemographic factors was used to identify independent predictors for ADT use. RESULTS: A total of 57,968 radiation-treated high-risk PCa men were included in our analysis. There were 49,363 patients (85.2%) treated with EBRT alone and 8605 patients (14.8%) treated with EBRT plus brachytherapy boost. Overall, 77% of men received ADT. In multivariable regression analysis, the use of brachytherapy boost was associated with a significantly lower utilization of ADT (70% vs. 78%; adjusted odds ratio [AOR]: 0.65; 95% CI: 0.62-0.69; p-Value <0.0001), as was treatment at an academic vs. nonacademic center (AOR: 0.90; 95% CI: 0.86-0.95; p-Value <0.0001) and treatment in 2010-2012 compared to 2004-2006 (AOR: 0.85; 95% CI: 0.81-0.90; p-Value <0.0001). Conversely, greater ADT use was seen with higher Gleason scores, PSA, and T-category (all p-Values <0.001). CONCLUSIONS: Approximately one in four men with radiation-managed high-risk PCa do not receive ADT, which may reflect concerns about its toxicity profile despite known improvements in overall survival. Practice patterns suggest that some providers believe dose escalation through brachytherapy boost may obviate the need for ADT in some high-risk patients, but this hypothesis requires further testing.


Asunto(s)
Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/radioterapia , Anciano , Anciano de 80 o más Años , Braquiterapia/métodos , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Pautas de la Práctica en Medicina/estadística & datos numéricos , Pautas de la Práctica en Medicina/tendencias , Análisis de Regresión , Estados Unidos
9.
Adv Drug Deliv Rev ; 105(Pt B): 190-204, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27262922

RESUMEN

Graphene and its derivatives have unique physical and chemical properties that make them promising vehicles for photothermal therapy (PTT)-based cancer treatment. With intrinsic near-infrared (NIR) absorption properties, graphene-based nanomaterials can be used for PTT and other therapeutics, particularly in combination therapy, to provide successful thermal ablation of cancer cells. In the recent years, advances in graphene-based PTT have produced efficient and efficacious tumor inhibition via nanomaterial structural design and different functionalizations of graphene-derived nanocomposites. Graphene-based nanosystems exhibit multifunctional properties that are useful for PTT applications including enhancement of multimodalities, guided imaging, enhanced chemotherapy and low-power efficient PTT for optimum therapeutic efficiency. Therefore, in this review, we address critical issues and future aspects of PTT-based combination therapy.


Asunto(s)
Grafito/uso terapéutico , Nanocompuestos/uso terapéutico , Neoplasias/terapia , Fototerapia , Animales , Terapia Combinada , Grafito/química , Humanos , Nanocompuestos/química
10.
Nanoscale ; 8(25): 12648-57, 2016 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26838477

RESUMEN

Sonodynamic therapy (SDT), which induces activation of sonosensitizers in cancer cells through ultrasound irradiation, has emerged as an alternative and promising noninvasive therapeutic approach to kill both superficial and deep parts of tumors. In this study, mesoporous silica (MSN) grown on reduced graphene oxide nanosheet (nrGO) capped with Rose Bengal (RB)-PEG-conjugated iron-oxide nanoparticles (IONs), nrGO@MSN-ION-PEG-RB, was strategically designed to have targeted functionality and therapeutic efficacy under magnetic guiding and focused ultrasound (FUS) irradiation, respectively. The singlet oxygen produced by ultrasound-activated RB and the ultrasound-induced heating effect was enhanced by rGO and IONs, which improved the cytotoxic effect in cancer cells. In an animal experiment, we demonstrated that the combination of sonodynamic/hyperthermia therapy with magnetic guidance using this nanocomposite therapeutic agent can produce remarkable efficacious therapy in tumor growth inhibition. Furthermore, the combination effect induced by FUS irradiation produces significant damage to both superficial and deep parts of the targeted tumor.


Asunto(s)
Compuestos Férricos , Grafito , Hipertermia Inducida , Nanoestructuras , Neoplasias Experimentales/terapia , Nanomedicina Teranóstica , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias , Dióxido de Silicio
11.
Small ; 12(11): 1458-68, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26814978

RESUMEN

A high-sensitivity and low-power theranostic nanosystem that combines with synergistic photothermal therapy and surface-enhanced Raman scattering (SERS) mapping is constructed by mesoporous silica self-assembly on the reduced graphene oxide (rGO) nanosheets with nanogap-aligned gold nanoparticles (AuNPs) encapsulated and arranged inside the nanochannels of the mesoporous silica layer. Rhodamine 6G (R6G) as a Raman reporter is then encapsulated into the nanochannels and anti-epidermal growth factor receptor (EGFR) is conjugated on the nanocomposite surface, defined as anti-EGFR-PEG-rGO@CPSS-Au-R6G, where PEG is polyethylene glycol and CPSS is carbon porous silica nanosheets. SERS spectra results show that rGO@CPSS-Au-R6G enhances 5 × 10(6) magnification of the Raman signals and thus can be applied in the noninvasive cell tracking. Furthermore, it displays high sensitivity (detection limits: 10(-8) m R6G solution) due to the "hot spots" effects by the arrangements of AuNPs in the nanochannels of mesoporous silica. The highly selective targeting of overexpressing EGFR lung cancer cells (A549) is observed in the anti-EGFR-PEG-rGO@CPSS-Au-R6G, in contrast to normal cells (MRC-5). High photothermal therapy efficiency with a low power density (0.5 W cm(-2) ) of near-infrared laser can be achieved because of the synergistic effect by conjugated AuNPs and rGO nanosheets. These results demonstrate that the anti-EGFR-PEG-rGO@CPSS-Au-R6G is an excellent new theranostic nanosystem with cell targeting, cell tracking, and photothermal therapy capabilities.


Asunto(s)
Receptores ErbB/metabolismo , Oro/química , Grafito/química , Hipertermia Inducida , Nanopartículas/química , Fototerapia , Dióxido de Silicio/química , Espectrometría Raman/métodos , Nanomedicina Teranóstica/métodos , Células A549 , Supervivencia Celular , Humanos , Rayos Láser , Microscopía Fluorescente , Nanopartículas/ultraestructura , Oxidación-Reducción , Porosidad
12.
Urology ; 87: 125-32, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26391387

RESUMEN

OBJECTIVE: To identify contemporary, clinically low-risk patients with ≥50% cores positive and compare the risk of upgrading at prostatectomy with other low- or intermediate-risk patients. MATERIALS AND METHODS: We studied 14,902 patients with prostate cancer in the Surveillance, Epidemiology, and End Results database in 2010-2011 treated with prostatectomy. Patients were categorized by National Comprehensive Cancer Network clinical risk groups, separating low-risk patients by percent positive biopsy cores (PBC). We measured incidence of pathologic high-risk disease, defined as pT3a-T4 or Gleason 8-10, and multivariable logistic regression was used to determine if patients with clinical low-risk disease and ≥50% PBC were similar to other low- or intermediate-risk patients. This analysis was repeated with favorable and unfavorable intermediate risk. RESULTS: At prostatectomy, 9.2% of clinically low-risk patients with <50% PBC, 18.6% of clinically low-risk patients with ≥50% PBC, and 27.6% of clinically intermediate-risk patients had occult, high-risk disease (P <.001). On multivariable logistic regression, low-risk patients with ≥50% PBC were more likely than low-risk patients with <50% PBC to have pathologic high-risk disease (adjusted odds ratio [AOR] 2.28, 95% confidence interval 1.90-2.73, P <.001), had similar risk to favorable intermediate patients overall (AOR 1.09, 0.91-1.31, P = .33), and had higher risk than favorable intermediate patients aged over 60 years (AOR 1.28, 1.00-1.64, P = .04). Low-risk patients with ≥50% PBC had a mean tumor size similar to unfavorable intermediate-risk patients (21.3 vs 21.0 mm, P = .82). CONCLUSION: Nearly 1 in 5 clinically low-risk prostate cancer patients with ≥50% PBC harbor occult pT3a-T4 or Gleason 8-10, suggesting that national guidelines should not classify low-risk patients with ≥50% cores positive as "low risk," and patients should be made aware of this excess risk if considering active surveillance.


Asunto(s)
Adenocarcinoma/diagnóstico , Guías como Asunto , Estadificación de Neoplasias/métodos , Neoplasias de la Próstata/diagnóstico , Medición de Riesgo/métodos , Programa de VERF , Adenocarcinoma/epidemiología , Anciano , Biopsia , Adhesión a Directriz , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Prostatectomía , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia/tendencias , Estados Unidos/epidemiología
13.
Arch Environ Contam Toxicol ; 69(4): 399-410, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26250452

RESUMEN

Red-necked grebes (Podiceps grisegena) are piscivorous waterbirds that breed on freshwater lakes in northwestern Canada and stop-over at the Great Lakes during autumn migration to molt feathers and replenish lipid and protein reserves. The objectives of this study were to (1) describe concentrations of, and correlations among, inorganic contaminants in a sample of autumn migrant red-necked grebes from the Great Lakes, (2) compare concentrations of inorganic contaminants to those in autumn migrant common loons from Schummer et al. (Arch Environ Contam Toxicol 62:704, 2011a), (3) evaluate if the inorganic elements are negatively associated with lipid and protein reserves, and (4) determine if nutrient reserves and molt intensity were correlated. None of the 14 contaminants analyzed were above threshold levels known to cause acute health problems in piscivorous birds. Body masses of plucked birds were within the normal reported range. Lipid reserves varied positively with hepatic concentrations of arsenic, copper, iron, nickel, lead, and selenium and negatively with mercury and magnesium. Protein reserves variety negatively with hepatic concentrations of arsenic, calcium, nickel, lead, and zinc and positively with aluminum, cadmium, and iron. A negative correlation was observed between chest molt and lipid reserves but not between nutrient reserves and other feather tracts. The relationships between lipid reserves and both mercury and selenium were consistent with current research on other piscivorous waterbirds at the Great Lakes and justify continued work to determine interactions of these contaminants in waterbirds that breed, stage, and winter in the region.


Asunto(s)
Aves/metabolismo , Monitoreo del Ambiente , Contaminantes Químicos del Agua/metabolismo , Animales , Arsénico/metabolismo , Bahías , Cadmio/metabolismo , Canadá , Plumas/química , Mercurio/metabolismo , Selenio/metabolismo
14.
Metallomics ; 6(3): 465-75, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24413477

RESUMEN

The effects of mercury added as Hg(2+) and selenium as selenite to cultures of the sulfate reducing bacterium Desulfovibrio desulfuricans were investigated under controlled laboratory conditions. There was no significant difference in the growth curves in comparison to control except in the 0.5 µM Hg-6.3 µM Se combined system in which Hg methylation was significantly reduced. A significant decrease in the production of methylmercury indicates a disruption of the methylation process due to the presence of the relatively high concentrations of Se in the system, suggesting a modification of the biological pathway. The results of detailed 2D gel electrophoresis in combination with mass spectrometry confirmed that the Hg methylation process should certainly be influenced when the protein Dde_1198 protein-glutamate O-methyltransferase was totally suppressed in a culture containing 0.5 µM Hg and 6.3 µM Se. Since this protein plays an important role in the methylation process, its suppression in the presence of Se brings a possible explanation for the antagonism between Se and Hg in natural systems. The experiment involving the determination of Hg and Se in membrane proteins separated by 1D gel thin-layer isoelectric focusing revealed that when both elements were present in a culture, the concentration of Hg in the separated proteins was significantly lower in comparison to those without added Se to the culture and vice versa. Finally, near-edge X-ray absorption spectroscopy and extended X-ray absorption fine structure were used to corroborate the presence of a very inert solid HgSe in the cell membrane obtained from the culture containing 0.5 µM Hg and 6.3 µM Se. This confirms the protective effect of Se against Hg assimilation at the molecular level and reinforces the findings of our research group in numerous field and laboratory studies.


Asunto(s)
Desulfovibrio desulfuricans/metabolismo , Mercurio/metabolismo , Compuestos de Metilmercurio/metabolismo , Selenio/metabolismo , Proteínas Bacterianas/metabolismo , Desulfovibrio desulfuricans/crecimiento & desarrollo , Metilación , Metiltransferasas/metabolismo
15.
Alcohol Clin Exp Res ; 38(3): 777-86, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24236888

RESUMEN

BACKGROUND: The neurotransmitter dopamine (DA), acting in various mesolimbic brain regions, is well known for its role in promoting motivated behaviors, including ethanol (EtOH) drinking. Indirect evidence, however, suggests that DA in the perifornical lateral hypothalamus (PF/LH) has differential effects on EtOH consumption, depending on whether it acts on the DA 1 (D1) or DA 2 (D2) receptor subtype, and that these effects are mediated in part by local peptide systems, such as orexin/hypocretin (OX) and melanin-concentrating hormone (MCH), known to stimulate the consumption of EtOH. METHODS: The present study in brain-cannulated Sprague-Dawley rats measured the effects of dopaminergic compounds in the PF/LH on drinking behavior in animals trained to consume 7% EtOH and also on local peptide mRNA expression using digoxigenin-labeled in situ hybridization in EtOH-naïve animals. RESULTS: Experiments 1 and 2 showed that the D1 agonist SKF81297 (10.8 nmol/side) in the PF/LH significantly increased food intake, while tending to increase EtOH intake, and the D1 antagonist SCH23390 significantly decreased EtOH intake without affecting food intake. In contrast, the D2 agonist quinelorane (6.2 nmol/side) in the PF/LH significantly reduced EtOH consumption, while the D2 antagonist sulpiride increased it. Experiments 3 and 4 revealed differential effects of PF/LH injection of the DA agonists on local OX mRNA, which was increased by the D1 agonist and decreased by the D2 agonist. These DA agonists had no impact on MCH expression. CONCLUSIONS: These results support a stimulatory role of the PF/LH D1 receptor in promoting the consumption of both EtOH and food, in contrast to a suppressive effect of the D2 receptor on EtOH drinking. They further suggest that these receptors affect consumption, in part, through local OX-expressing neurons. These findings provide new evidence for the function of PF/LH DA receptor subtypes in controlling EtOH and food intake.


Asunto(s)
Consumo de Bebidas Alcohólicas/metabolismo , Ingestión de Alimentos/fisiología , Hipotálamo/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animales , Hormonas Hipotalámicas/metabolismo , Hibridación in Situ , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Melaninas/metabolismo , Neuropéptidos/metabolismo , Receptores de Orexina/metabolismo , Orexinas , Hormonas Hipofisarias/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1/agonistas , Receptores de Dopamina D1/antagonistas & inhibidores , Receptores de Dopamina D2/agonistas
16.
Environ Pollut ; 175: 8-15, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23313732

RESUMEN

Accumulation of selenium (Se) by lesser and greater scaup (Aythya affinis, A. marila) at staging and wintering areas could have contributed to the decline in their continental population. We exposed lesser scaup to background (0.8 µg/g), moderate (8.1 µg/g) and high (20.7 µg/g) levels of dietary Se in captivity and measured survival rates and indices of health in relation to hepatic Se concentrations. There was 100% survival in scaup exposed to Se for 10-weeks (average staging duration at Great Lakes), but ducks in the high treatment group had less lipids. There was 93% survival after 23-weeks (average wintering duration at Great Lakes), but no differences among treatment groups in body composition. There were no effects of Se on oxidative stress and cell-mediated immunity; rather we recorded immuno-stimulatory effects on antibody production. Results from our captive study suggest Se alone did not cause the continental decline in scaup populations.


Asunto(s)
Anseriformes/metabolismo , Dieta/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/toxicidad , Selenio/toxicidad , Animales , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Contaminantes Ambientales/metabolismo , Estaciones del Año , Selenio/análisis , Selenio/metabolismo
17.
Alcohol ; 47(1): 31-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23199698

RESUMEN

The opioid system is known to enhance motivated behaviors, including ethanol drinking and food ingestion, by acting in various reward-related brain regions, such as the nucleus accumbens, ventral tegmental area and medial hypothalamus. There is indirect evidence, however, suggesting that opioid peptides may act differently in the perifornical lateral hypothalamus (PF/LH), causing a suppression of consummatory behavior. Using brain-cannulated Sprague-Dawley rats trained to voluntarily drink 7% ethanol, the present study tested the hypothesis that opioids in the PF/LH can reduce the consumption of ethanol, with animals receiving PF/LH injections of the δ-opioid receptor agonist D-Ala2-met-enkephalinamide (DALA), the µ-receptor agonist [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO), the κ-receptor agonist (±)-trans-U-50,488 methanesulfonate (U-50,488H), or the general opioid antagonist methylated naloxone (m-naloxone). The consumption of ethanol, lab chow, and water was monitored for 4 h after injection. The results showed that the three opioid receptor agonists injected into the PF/LH specifically and significantly reduced ethanol intake, while causing little change in chow or water intake, and the opposite effect, enhanced ethanol intake, was observed with the opioid antagonist. Of the three opioid agonists, the δ-agonist appears to produce the most consistent and long-lasting suppression of consumption. This effect was not observed with injections 2 mm dorsal to this area, focusing attention on the PF/LH as the main site of action. These results suggest that the opioid peptides have a specific role in the PF/LH of reducing ethanol drinking, which is distinct from their more commonly observed appetitive actions in other brain areas. The additional finding, that m-naloxone in the PF/LH stimulates ethanol intake in contrast to its generally suppressive effect in other regions, focuses attention on this hypothalamic area and its distinctive role in contributing to the variable effects sometimes observed with opioid antagonist therapy for alcoholism.


Asunto(s)
Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Analgésicos Opioides/farmacología , Hipotálamo/efectos de los fármacos , 3,4-Dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclohexil)-bencenacetamida, (trans)-Isómero/farmacología , Animales , Encefalina Ala(2)-MeFe(4)-Gli(5)/farmacología , Encefalina Metionina/análogos & derivados , Encefalina Metionina/farmacología , Naloxona/análogos & derivados , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Ratas , Ratas Sprague-Dawley , Receptores Opioides/agonistas
18.
Adv Mater ; 24(13): 1748-54, 2012 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-22422734

RESUMEN

Quantum-dot-tagged reduced graphene oxide (QD-rGO) nanocomposites (left) internalized into targeted tumor cells display bright fluorescence from the QDs (right); by absorbing NIR radiation incident on the rGO and converting it into heat, they also cause simultaneous cell death and fluorescence reduction (bottom). The nanocomposite is thus capable of tumor imaging, photothermal therapy and in situ monitoring of treatment in progress.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Grafito/uso terapéutico , Nanocompuestos/uso terapéutico , Puntos Cuánticos , Supervivencia Celular/efectos de la radiación , Femenino , Fluorescencia , Grafito/química , Células HeLa , Humanos , Hipertermia Inducida/métodos , Nanocompuestos/química , Oxidación-Reducción , Óxidos/química , Óxidos/uso terapéutico , Fototerapia/métodos
19.
Arch Environ Contam Toxicol ; 62(4): 704-13, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22042040

RESUMEN

Common loons (Gavia immer) are piscivorous, high-trophic level feeders that bioaccumulate inorganic contaminants at concentrations that can negatively impact their health and reproduction. Concentrations of inorganic contaminants, especially mercury (Hg), in blood, organs, and muscle have been quantified in common loons on breeding grounds, but these data are limited for migrating loons. We investigated sex- and age-related hepatic concentrations of inorganic contaminants in common loons (n = 53) that died from botulism and were salvaged at a Great Lakes staging area (i.e., Long Point, Lake Erie) during November 2005. We also investigated if hepatic concentrations of inorganic contaminants influenced lipid, protein, and mineral in our sample of migrant common loons. Last, we determined if there was correlation between Hg and selenium (Se). Consistent with data from breeding grounds, mean concentrations of Hg in liver were approximately 2.5 times greater in adult ([Formula: see text] = 14.64 ± 16.69 µg g(-1)) compared with juvenile birds ([Formula: see text] = 3.99 ± 2.27 µg g(-1)). Elements detected in liver at potentially harmful levels were Hg and Se, of which lipid reserves varied negatively with Hg concentrations but positively with Se concentrations. In addition, Hg and Se were correlated (r = 0.65) at greater then a demethylation threshold (total Hg ≥ 8.5 µg g(-1) dw) but not lower than that. Concentrations of inorganic contaminants did not influence protein and mineral levels in our sample of common loons. Our results suggest that Hg accumulation negatively affects lipid levels in migrant common loons. Results are also consistent with a nontoxic Hg-Se protein complex protecting loons migrating through areas that are relatively Se rich. Although the acquisition of Se during the nonbreeding season may decrease the toxicity of Hg, future research should consider the synergistic Hg-Se effect on reproduction in common loons that migrate through Se-rich locales, such as the Great Lakes.


Asunto(s)
Aves/metabolismo , Hígado/metabolismo , Mercurio/farmacocinética , Selenio/farmacocinética , Contaminantes Químicos del Agua/farmacocinética , Factores de Edad , Migración Animal , Animales , Canadá , Femenino , Lagos , Lípidos/análisis , Masculino , Metales/farmacocinética , Proteínas/análisis , Proteínas/metabolismo , Selenio/sangre , Contaminantes Químicos del Agua/sangre
20.
Arch Environ Contam Toxicol ; 61(4): 677-87, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21424222

RESUMEN

Contaminant inputs to the lower Great Lakes (LGL) have decreased since the 1960s and 1970s, but elemental contaminants continue to enter the LGL watershed at levels that are potentially deleterious to migratory waterfowl. Mute swans (Cygnus olor) using the LGL primarily eat plants, are essentially nonmigratory, forage exclusively in aquatic systems, and have increased substantially in number in the last few decades. Therefore, mute swans are an ideal sentinel species for monitoring elemental contaminants available to herbivorous and omnivorous waterfowl that use the LGL. We investigated hepatic concentrations, seasonal dynamics, and correlations of elements in mute swans (n = 50) collected at Long Point, Lake Erie, and Lake St. Clair from 2001 to 2004. Elements detected in liver at levels potentially harmful to waterfowl were copper (Cu) [range 60.3 to 6063.0 µg g(-1) dry weight (dw)] and selenium (SE; range 1.6 to 37.3 µg g(-1) dw). Decreases in aluminum, Se, and mercury (Hg) concentrations were detected from spring (nesting) through winter (nonbreeding). Elemental contaminants may be more available to waterfowl during spring than fall and winter, but study of seasonal availability of elements within LGL aquatic systems is necessary. From April to June, 68% of mute swans had Se levels >10 µg g(-1), whereas only 18% of swans contained these elevated levels of Se from July to March. An increase in the number of mute swans at the LGL despite elevated levels of Cu and Se suggests that these burdens do not substantially limit their reproduction or survival. Se was correlated with Cu (r = 0.85, p < 0.01) and Hg (r = 0.65, p < 0.01), which might indicate interaction between these elements. Some element interactions decrease the toxicity of both elements involved in the interaction. We recommend continued research of elemental contaminant concentrations, including detailed analyses of biological pathways and element forms (e.g., methylmercury) in LGL waterfowl to help determine the role of element interactions on their toxicity in waterfowl.


Asunto(s)
Anseriformes/fisiología , Hígado/metabolismo , Metales Pesados/metabolismo , Metales Ligeros/metabolismo , Contaminantes Químicos del Agua/metabolismo , Aluminio/análisis , Aluminio/metabolismo , Animales , Carga Corporal (Radioterapia) , Cobre/análisis , Cobre/metabolismo , Monitoreo del Ambiente , Femenino , Lagos , Hígado/química , Masculino , Mercurio/análisis , Mercurio/metabolismo , Metales Pesados/análisis , Metales Ligeros/análisis , Selenio/análisis , Selenio/metabolismo , Contaminantes Químicos del Agua/análisis
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