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1.
Ecotoxicol Environ Saf ; 286: 117218, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39426108

RESUMEN

The heavy metal, cadmium (Cd) is an increasingly serious issue in agricultural ecosystems, mediating bottom-up effects on plants, herbivores and natural enemies. We measured how Cd modifies interactions between tomato Solanum lycopersicum, western flower thrips Frankliniella occidentalis, and the predatory bug Orius sauteri by examining Cd effects on the growth of tomato, the fitness of western flower thrips, and the survival and behavior of predators. The photosynthetic parameters of Pn (net photosynthetic rate), Gs (stomatal conductance), Ci (intercellular CO2 concentration), and Tr (transpiration rate) of tomato plants significantly decreased with the increase of Cd concentration. The total survival number of western flower thrips fed on tomato plants treated with different concentrations of Cd was significantly lower than that of the control, and sex ratios (female/male) gradually increased with the increase of Cd concentration. The numbers of thrips predated by O. sauteri on tomato plants treated with high concentrations of Cd (2.0 or 4.0 mg/L) were significantly reduced by the second day. Cadmium was accumulated and bioconcentrated in the roots, stems, leaves of tomato plants, and transferred to F. occidentalis, and O. sauteri. Cadmium translocated in significant quantities from roots to the stems and leaves of tomato plants, and from the tomato leaf to F. occidentalis. However, there was minimal (non-significant) transfer of Cd from F. occidentalis to O. sauteri. The presence of Cd significantly reduced the growth of tomato plants, the fitness of F. occidentalis, and the predation efficiency of O. sauteri. Collectively, Cd can mediate bottom-up effects on tomato, thrip, and predatory bug along food chain, potentially interrupting pest biological control in tomato in heavy metal-contaminated ecosystems.

2.
Ecotoxicology ; 33(9): 973-983, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39066991

RESUMEN

Cadmium (Cd), a widely distributed environmental pollutant in agroecosystems, causes negative effects on crops and herbivores through bottom-up processes. The gut microbial community of an insect can play a critical role in response to metal stress. To understand how microbiota affect the stress responses of organisms to heavy metals in agroecosystems, we initially used 16S rRNA sequencing to characterize the larval gut microbiota of Chilo suppressalis, an important agricultural pest, exposed to a diet containing Cd. The species richness, diversity, and composition of the gut microbial community was then analyzed. Results revealed that while the richness (Chao1 and ACE) of gut microbiota in larvae exposed to Cd was not significantly affected, diversity (Shannon and Simpson) was reduced due to changes in species distribution and relative abundance. Overall, the most abundant genus was Enterococcus, while the abundance of the genera Micrococcaceae and Faecalibaculum in the control significantly superior to that in Cd-exposed pests. Phylogenetic investigation of microbial communities by the reconstruction of unobserved states (PICRUSt) showed that the intestinal microorganisms appear to participate in 34 pathways, especially those used in environmental information processing and the metabolism of the organism. This study suggests that the gut microbiota of C. suppressalis are significantly impacted by Cd exposure and highlights the importance of the gut microbiome in host stress responses and negative effects of Cd pollution in agroecosystems.


Asunto(s)
Microbioma Gastrointestinal , Larva , Metales Pesados , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Larva/efectos de los fármacos , Metales Pesados/toxicidad , Cadmio/toxicidad , ARN Ribosómico 16S , Mariposas Nocturnas/efectos de los fármacos
3.
J Magn Reson Imaging ; 44(1): 30-40, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26588793

RESUMEN

BACKGROUND: The aim of this study was to assess the diagnostic accuracy of diffusion kurtosis magnetic resonance imaging parameters for differentiating high-grade gliomas (HGGs) from primary central nervous system lymphomas (PCNSLs). METHODS: Diffusion parameters, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ// ), radial diffusivity (λ⊥ ); and kurtosis parameters, including mean kurtosis (MK), axial kurtosis (K// ), and radial kurtosis (K⊥ ), were normalized to contralateral normal-appearing white matter (NAWMc) to decrease inter-individual and inter-regional changes across the entire brain, and then compared with the solid parts of 20 HGGs and 11 PCNSLs [median 95% confidence interval (CI), P < 0.004; 0.05/14], significance level, Kolmogorov-Smirnov test, Bonferroni correction]. RESULTS: FA, MD, λ// , and λ⊥ values were higher in HGGs than in PCNSLs, but not significantly [HGGs: 0.209 (95% CI, 0.134-0.338), 1.385 (95% CI, 1.05-1.710), 1.655 (95% CI, 1.30-2.060), 1.228 (95% CI, 0.932-1.480), respectively; PCNSLs: 0.143 (95% CI, 0.110-0.317), 1.070 (95% CI, 0.842-1.470), 1.260 (95% CI, 0.960-1.930), 1.010 (95% CI, 0.782-1.240)], respectively; P = 0.120, 0.010, 0.004, and 0.004, respectively). However, MK and K// were significantly higher in PCNSLs compared with HGGs [PCNSLs: 0.765 (95% CI, 0.697-0.890), 0.787 (95% CI, 0.615-1.030), respectively; HGGs: 0.531 (95% CI, 0.402-0.766), 0.532 (95% CI, 0.432-0.680], respectively; P = 0.001, 0.000, respectively); but not K⊥ [0.774 (95% CI, 0.681-0.899) for PCNSLs; 0.554 (95% CI, 0.389-0.954) for HGGs; P = 0.024]. CONCLUSION: There were significant differences in kurtosis parameters (MK and K// ) between HGGs and PCNSLs, while differences in diffusion parameters between them did not reach significance; hence, better separation was achieved with these parameters than with conventional diffusion imaging parameters. J. Magn. Reson. Imaging 2016;44:30-40.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Imagen de Difusión por Resonancia Magnética/métodos , Glioma/diagnóstico por imagen , Glioma/patología , Linfoma/diagnóstico por imagen , Linfoma/patología , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
4.
Hypertens Res ; 47(6): 1523-1532, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38459173

RESUMEN

Frailty is the most important risk factor causing disability in the elderly. Hypertension is one of the most common chronic diseases in the elderly and is closely related to frailty, but there is still controversy about the association between blood pressure and frailty. To explore the association between baseline blood pressure level and the incident and development of long-term frailty in the community-dwelling very elderly (i.e., over 80 years old [1]) with hypertension, in order to provide a basis for scientific blood pressure management of very elderly hypertension. In this study, very elderly hypertensive patients who received comprehensive geriatric assessment from January to June 2019 and with complete data were included, and follow-up was conducted from January 1 to February 14, 2023. A total of 330 very elderly individuals with hypertension were enrolled in this study. FRAIL scale was used to evaluate frailty. Binomial logistic regression analysis was used to calculate the OR and 95%CI between baseline systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP) levels and long-term incident and development of frailty. The dose-response relationship between baseline office SBP, DBP or PP levels and incident frailty and its development was analyzed by Generalized Additive Model (GAM) using smooth curve fitting and threshold effect analysis. Smooth curve fitting and threshold effect analysis showed that the relationship between baseline office SBP level and incident frailty was U-shaped, with the nadir of the U-shaped curve at 135 mmHg after adjustment. Baseline office SBP, PP level and development frailty was U-shaped and the nadir was 140 mmHg and 77 mmHg. In the community-dwelling very elderly with hypertension, baseline office SBP level had a relationship with long-term incident frailty and its development and PP level had a relationship with long-term development of frailty.


Asunto(s)
Presión Sanguínea , Fragilidad , Hipertensión , Vida Independiente , Humanos , Hipertensión/fisiopatología , Hipertensión/epidemiología , Masculino , Femenino , Anciano de 80 o más Años , Presión Sanguínea/fisiología , Fragilidad/fisiopatología , Incidencia , Anciano Frágil , Evaluación Geriátrica
5.
Environ Sci Pollut Res Int ; 30(15): 43126-43136, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36648731

RESUMEN

Heavy metal contaminants may influence tri-trophic interactions among plants, herbivores, and their natural enemies and affect the results of pest management practices. We examined how the widely distributed heavy metal cadmium (Cd) could modify interactions between kidney bean, Phaseolus vulgaris L., western flower thrips, Frankliniella occidentalis Pergande, and a predator, Orius sauteri (Poppius) by examining Cd effects on the feeding damage on leaves, the growth and reproduction of the thrips, and the feeding and plant location selection behaviors of predators. Leaf feeding damage was significantly reduced only at the highest Cd treatment (625 mg L-1). Survival, reproduction, and population growth of thrips decreased with the increase of Cd treatment concentration (0, 25, and 625 mg L-1). The reproduction rate of thrips from the highest Cd treatment group was reduced to less than 30% of the controls. Predator choice of plants was not impacted at the lowest level of Cd treatment (25 mg L-1) when prey were excluded, but the predators were deterred from plants treated at the high level of Cd (625 mg L-1). However, the predators responded strongly to the presence of prey, and the Cd-based deterrence was effectively eliminated when prey were added. Thus, the presence of Cd can cause a bottom-up effect on the fitness of pests without disrupting the foraging behavior of its predator. Our results provide baseline data on the toxic impacts on the pest and predator, and indicate that the ecology of the system and the biological control efficiency would be potentially impacted by high levels of Cd (625 mg L-1).


Asunto(s)
Heterópteros , Thysanoptera , Animales , Cadmio , Plantas , Reproducción
6.
J Econ Entomol ; 116(4): 1146-1154, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37267079

RESUMEN

Mirid predators are increasingly used in biological control of multiple greenhouse crops pests. However, due to great morphological similarity and tiny body size, some mirid predators have been largely confused with their allied species. Nesidiocoris tenuis Reuter as a commercial mirid predator was confused largely with Nesidiocoris poppiusi Carvalho in China. To evaluate the biocontrol potential of N. poppiusi, its biological traits and the functional response to Bemisia tabaci Gennadius were studied compared with N. tenuis under laboratory conditions. The results showed that no significant differences of the developmental times from the first instar to adult stages between the 2 mirids fed on Corcyra cephalonica Stainton eggs were observed, while N. poppiusi had better population growth parameters than N. tenuis. Under the condition with prey, both female and male of N. poppiusi lived significantly longer than those of N. tenuis. It could lay 74.0 eggs, which was significantly higher than that of N. tenuis (30.2 eggs). Under the condition without prey, both N. poppiusi and N. tenuis couldn't complete development to adulthood on tomato, tobacco, muskmelon, and cabbage leaves, however, tobacco and tomato were more suitable than the other 2 plants. A type II functional response was observed for both males and females of the 2 predators. Nesidiocoris poppiusi females consumed significantly more B. tabaci pupae than N. tenuis when prey densities were large than 30. Our results indicated that N. poppiusi could be a promising candidate for biological control of B. tabaci.


Asunto(s)
Heterópteros , Solanum lycopersicum , Femenino , Masculino , Animales , Heterópteros/fisiología , Conducta Predatoria , Productos Agrícolas , China , Control Biológico de Vectores
7.
Am J Mens Health ; 16(4): 15579883221108898, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35801533

RESUMEN

The prostatic abscess is a rare complication of a bacterial infection of the prostate. Since the early use of potent antibiotics to treat urinary tract infections, the incidence of the prostatic abscess has declined significantly. In keeping with that, prostatic abscess combined with abscesses in the spleen or other distant organs become an extremely rare but fatal clinical condition. Here, we present a case of prostate and spleen abscess due to multi-drug-resistant gram-negative bacilli without obvious risk factors. The patient initially complained of high-grade fever and dysuria. After screening the source of infection by computed tomography (CT) scans, prostate and spleen abscesses were diagnosed. In addition, extended-spectrum beta-lactamase positive Escherichia coli was detected both in urine and blood culture. The patient was successfully treated by a transurethral resection of the prostate followed by splenic puncture and drainage, as well as intravenous administration of meropenem. Although the prostate abscess combined with spleen abscess was rare, the possibility of dissemination in remote tissues should be taken into consideration before the surgical treatment of prostatic abscesses. The concurrent drainage of multiple abscesses followed by intensive and sensitive antibiotics was safe and effective for indicated patients.


Asunto(s)
Enfermedades de la Próstata , Resección Transuretral de la Próstata , Absceso/diagnóstico por imagen , Absceso/etiología , Antibacterianos/uso terapéutico , Humanos , Masculino , Enfermedades de la Próstata/diagnóstico por imagen , Bazo/diagnóstico por imagen , Resección Transuretral de la Próstata/efectos adversos
8.
Insects ; 12(12)2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34940151

RESUMEN

The lepidopteran pest, Spodoptera frugiperda (JE Smith), spread rapidly after its first detection in China and has caused significant yield loss to maize production in the southwestern part of the country. Although natural enemies of S. frugiperda are present in the field, biological control using naturally distributed predators is ineffective because their underlying populations are too low. To enhance our understanding of the potential role of natural enemies in regulating this invasive pest, functional response experiments were conducted to quantify the response of two predators, Orius sauteri (Poppius) (Hemiptera: Anthocoridae) and Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), in terms of consumption of S. frugiperda. Experimental results revealed that the predatory effects of nymphs of O. sauteri and H. axyridis on the eggs and larvae of S. frugiperda fitted Holling's Type II functional response model. Importantly, the theoretical maximum number of prey consumed per day (Na-max), the instantaneous attack rate (a') and the handling time (Th) of O. sauteri nymphs on S. frugiperda eggs were 15.19, 0.7444 and 0.049 d, respectively; and the parameters on first instar larvae of S. frugiperda were 700.24, 0.5602 and 0.0008 d, respectively. These data contrast to those of H. axyridis, where the Na-max, a' and Th of adults on eggs of S. frugiperda were 130.73, 1.1112 and 0.085 d, respectively, and on the first instar larvae of S. frugiperda were 1401.1, 0.8407 and 0.0006 d, respectively. These results revealed that H. axyridis is a highly voracious predator of the eggs and young larvae of S. frugiperda and O. sauteri could also be used as biocontrol agent of this pest. Our work provides a theoretical framework for the application of natural enemies to control S. frugiperda in the field. Further research is required to strategize conservation biological control approaches in the field to increase populations of these predators and enhance the suppression of S. frugiperda.

9.
Chem Commun (Camb) ; 57(48): 5901-5904, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34008620

RESUMEN

By using in-site generated formate, 2D HOFs of TCPP, with excellent stability and permanent porosity (BET surface area larger than 560 m2 g-1), have been obtained. The constructed 2D square-like TCPP-HCO2 grid sheets have shown considerable in-plane stability that comparable to the TCPP-based 2D MOFs, that can be exfoliated into atomically thin 2D nanosheets with efficient photocatalytic activity in aqueous system. These results are expected to shed light on the application-orientated one-pot synthesis for new kinds of multi-dimensional HOFs.

10.
Ann Palliat Med ; 9(5): 2926-2932, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32819121

RESUMEN

BACKGROUND: Since sepsis-3 definition is more accurate and sensitive than previous sepsis definition, implementation the newest diagnosis criteria could definitely bring more benefit to sepsis patients. This study was done to identify the level of current intensivists' knowledge regarding the third international consensus definitions for sepsis and septic shock and its implementation for the diagnosis of sepsis among Chinese adult intensive care units (ICUs). METHODS: A nationwide survey amongst critical care physicians was designed. The questionnaires measured the understanding and the frequency of diagnosis of sepsis and septic shock according to the third international consensus definitions for sepsis and septic shock. One thousand random physician members of Chinese Society of Critical Care Medicine were involved in the survey. A 5-point Likert scale (totally understand, partially understand, understand, hardly understand, do not understand) was used to elicit answers about the degree of understanding the sepsis-3 definition. The other 5-point Likert scale (always, often, sometimes, rarely, never) was used to elicit answers about the frequency of diagnosing sepsis according to the sepsis-3 definition. RESULTS: There were 59 (16.1%) intensivists who could completely understand the sepsis-3 definition. Less practiced intensivists could understand the sepsis-3 definition better than more practiced intensivists (P<0.001). Intensivists from university teaching hospitals understand the sepsis-3 definition better than the intensivists from the community hospitals (P<0.001). Intensivists from small-sized ICUs understand the sepsis-3 definition better than intensivists from big-sized ICUs (P<0.001). There were 60 (16.4%) intensivists who always diagnose sepsis according to the sepsis-3 definition since sepsis-3 published. Less practiced intensivists prefer using the sepsis-3 definition to diagnose sepsis compared with more practiced intensivists (P<0.001). Intensivists from university teaching hospitals prefer using the sepsis-3 definition to diagnose sepsis compared with the intensivists from the community hospitals (P<0.001). Intensivists from small-sized ICUs prefer adapting sepsis-3 definition to diagnosis sepsis compared with intensivists from big-sized ICUs (P<0.001). CONCLUSIONS: In current China, the sepsis-3 definition is well understood and accepted by intensivists.


Asunto(s)
Sepsis , Choque Séptico , Adulto , China , Humanos , Unidades de Cuidados Intensivos , Sepsis/diagnóstico , Choque Séptico/diagnóstico , Encuestas y Cuestionarios
11.
Artículo en Inglés | MEDLINE | ID: mdl-32599020

RESUMEN

Honey bees (Apis mellifera L.) are important ecological and agricultural resources. They are among the most widely available pollinators and provide products as well as services. Unfortunately, honey bee populations are susceptible to several environmental threats, including heavy metal exposure. Honey bees can be exposed to heavy metals when foraging on contaminated honey and pollen resources, and in some cases by airborne exposure. We studied the joint acute and chronic effects of cadmium (Cd) and copper (Cu) on A. mellifera. A 1:1 solution of the two heavy metals increased larval developmental duration and the mortality of both larvae and foragers in a dose-dependent way, decreased forager feeding, increased body metal burdens, and disrupted the sucrose response behavior of foragers. In combination, Cd and Cu demonstrated a weakly synergistic effect on foragers, but for larvae an initially antagonistic effect at low doses changed to strongly synergistic response at higher concentrations. The sucrose response threshold of foragers decreased significantly when they were dosed with increasing concentrations of the metal mixtures. Overall, the fitness of honey bee larvae and foragers is detrimentally affected when these metals co-occur.


Asunto(s)
Abejas/efectos de los fármacos , Cadmio/toxicidad , Cobre/toxicidad , Animales , Abejas/fisiología , Combinación de Medicamentos , Sinergismo Farmacológico , Conducta Alimentaria/efectos de los fármacos , Intoxicación por Metales Pesados/etiología , Intoxicación por Metales Pesados/patología , Larva/efectos de los fármacos , Sacarosa/metabolismo , Pruebas de Toxicidad Aguda
12.
Front Physiol ; 9: 1392, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30337884

RESUMEN

Herbivores respond differently to the level of plant diversity encountered. Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) are highly polyphagous herbivores which cause considerable damage to various crops. Herein, we reared this species both in polyculture and monoculture, including preferred and less preferred host plants such as Chinese cabbage (Brassica rapa L.), tomato (Solanum lycopersicum L.), kidney bean (Phaseolus vulgaris L.) and summer squash (Cucurbita pepo L.). Trends in survival and oviposition were recorded, and impact of plants on growth and development of B. tabaci were studied, particularly in terms of detoxification and digestive enzymatic activity in the insects. We found that the survival rate was the highest in Chinese cabbage monoculture treatment. Further, the egg numbers on individual species in the polyculture generally reflected numbers on the same plant species in monoculture. However, more eggs were observed in each of the four plant species tested in the context of polyculture. The activity of superoxide dismutases (SOD) and alkaline phosphatase (AKP) in B. tabaci fed in a choice situation were significantly lower than those fed with tomato monoculture, indicating a dilution of toxicity with a multi-plant diet compared with less preferred host plant diet. Also, the survival rate of B. tabaci in monoculture was negatively correlated with SOD amount of whitefly. In the plants attacked by whiteflies, the activity of polyphenol oxidase (PPO) and catalase (CAT) in Chinese cabbage was lower in polyculture than in the monoculture. These results implied that multi-plant treatments contained fewer secondary metabolite substances and might be less toxic to polyphagous herbivores. As such, the work herein contributes knowledge relevant for more effective control and management of B. tabaci.

13.
Environ Toxicol Chem ; 35(2): 322-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26448590

RESUMEN

Metal pollution has been increasing rapidly over the past century, and at the same time, the human population has continued to rise and produce contaminants that may negatively impact pollinators. Honey bees (Apis mellifera L.) forage over large areas and can collect contaminants from the environment. The primary objective of the present study was to determine whether the metal contaminants cadmium (Cd), copper (Cu), lead (Pb), and selenium (Se) can have a detrimental effect on whole-colony health in the managed pollinator A. mellifera. The authors isolated small nucleus colonies under large cages and fed them an exclusive diet of sugar syrup and pollen patty spiked with Cd, Cu, Pb, and Se or a control (no additional metal). Treatment levels were based on concentrations in honey and pollen from contaminated hives around the world. They measured whole-colony health including wax, honey, and brood production; colony weight; brood survival; and metal accumulation in various life stages. Colonies treated with Cd or Cu contained more dead pupae within capped cells compared with control, and Se-treated colonies had lower total worker weights compared to control. Lead had a minimal effect on colony performance, although many members of the hive accumulated significant quantities of the metal. By examining the honey bee as a social organism through whole-colony assessments of toxicity, the authors found that the distribution of toxicants throughout the colony varied from metal to metal, some caste members were more susceptible to certain metals, and the colony's ability to grow over time may have been reduced in the presence of Se. Apiaries residing near metal-contaminated areas may be at risk and can suffer changes in colony dynamics and survival.


Asunto(s)
Abejas/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Metales Pesados/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Dieta , Contaminantes Ambientales/análisis , Salud , Metales Pesados/análisis , Polinización , Reproducción/efectos de los fármacos , Conducta Social , Ceras/análisis
14.
Chemosphere ; 152: 530-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27011322

RESUMEN

Honeybees (Apis mellifera L.) have been widely distributed around the world to serve as pollinators for agriculture. They can encounter metal pollutants through various routes of exposure, including foraging on contaminated plant resources. Chronic and acute toxicity tests were conducted on larvae using artificial diets and on foragers using solutions of 50% sucrose, which contained cadmium (Cd), copper (Cu) and lead (Pb). We found that mortality increased in both larvae and foragers in a dose-dependent manner. Control larvae had higher relative growth indices (RGI) from day 6 to day 10 compared to all metal treatments, demonstrating substantial negative effects of metals on development. Copper was the least toxic to larvae with an LC50 of 6.97 mg L(-1). For foragers, Pb had the highest LC50, which was 345 mg L(-1). Foragers and larvae accumulated substantial quantities of all metals, and subsequent sucrose consumption decreased after dosing. Overall, honeybee larvae and foragers suffered detrimental effects when they were exposed to ecologically-relevant concentrations of Cd, Cu and Pb.


Asunto(s)
Abejas/efectos de los fármacos , Cadmio/toxicidad , Cobre/toxicidad , Plomo/toxicidad , Animales , Abejas/crecimiento & desarrollo , Abejas/metabolismo , Bioensayo , Cadmio/farmacocinética , Cobre/farmacocinética , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/metabolismo , Plomo/farmacocinética , Pruebas de Toxicidad Aguda
15.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 29(4): 376-9, 384, 2013 Jul.
Artículo en Zh | MEDLINE | ID: mdl-24175568

RESUMEN

OBJECTIVE: To observe the effects of beta3-adrenergic receptor(beta3-AR) antagonist on myocardial uncoupling protein 2 (UCP2) expression and energy metabolism in chronic heart failure rats. METHODS: Seven weight-matched normal adult rats (control group), 18 isoproterenol (ISO) induced heat failure (HR) rats (ISO group) and 21 ISO induced heart failure rats but received specific beta3-AR inhibitor SR59230A (ISO+ SR59230A group) for 6 weeks were included in this research. At the end of the study, echocardiography was performed, the ratio of left ventricular weight and body weight (LVW/BW) was calculated. The expression of beta3-AR ad UCP2 mRNA in myocardium were detected by reverse transcription-polymerase chain reaction (RT-PCR), the UCP2 protein in myocardium were detected by Western blot. The myocardial contents of creatine phosphate (PCr) and adenosine triphosphate (ATP) were measured by high performance liquid chromatography (HPLC). RESULTS: Compared with control group, the cardiac function was significantly reduced and myocardial beta3-AR mRNA significantly increased, UCP2 mRNA and protein were also significantly increased in ISO group, this change could be attenuated by the treatment with SR59230A, and the expression of myocardial UCP2 protein negatively correlated with the ratio of PCr/ATP. CONCLUSION: In the chronic stage of HF, the expression of UCP2 increases, which causes myocardial energy shortage, SR59230A improves myocardia energy efficiency and cardiac function by means of suppressing the expression of UCP2.


Asunto(s)
Antagonistas Adrenérgicos/farmacología , Insuficiencia Cardíaca/metabolismo , Canales Iónicos/metabolismo , Proteínas Mitocondriales/metabolismo , Miocardio/metabolismo , Animales , Metabolismo Energético , Masculino , Ratas , Ratas Wistar , Receptores Adrenérgicos beta 3/metabolismo , Proteína Desacopladora 2
16.
Tissue Eng Part C Methods ; 19(12): 925-36, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23557537

RESUMEN

Tissue engineering techniques using novel scaffolding materials offer potential alternatives for managing tendon disorders. An ideal tendon tissue engineered scaffold should mimic the three-dimensional (3D) structure of the natural extracellular matrix (ECM) of the native tendon. Here, we propose a novel electrospun nanoyarn network that is morphologically and structurally similar to the ECM of native tendon tissues. The nanoyarn, random nanofiber, and aligned nanofiber scaffolds of a synthetic biodegradable polymer, poly(L-lactide-co-ε-caprolactone) [P(LLA-CL)], and natural collagen I complex were fabricated using electrospinning. These scaffolds were characterized in terms of fiber morphology, pore size, porosity, and chemical and mechanical properties for the purpose of culturing tendon cells (TCs) for tendon tissue engineering. The results indicated a fiber diameter of 632 ± 81 nm for the random nanofiber scaffold, 643 ± 97 nm for the aligned nanofiber scaffold, and 641 ± 68 nm for the nanoyarn scaffold. The yarn in the nanoyarn scaffold was twisted by many nanofibers similar to the structure and inherent nanoscale organization of tendons, indicating an increase in the diameter of 9.51 ± 3.62 µm. The nanoyarn scaffold also contained 3D aligned microstructures with large interconnected pores and high porosity. Fourier transform infrared analyses revealed the presence of collagen in the three scaffolds. The mechanical properties of the sample scaffolds indicated that the scaffolds had desirable mechanical properties for tissue regeneration. Further, the results revealed that TC proliferation and infiltration, and the expression of tendon-related ECM genes, were significantly enhanced on the nanoyarn scaffold compared with that on the random nanofiber and aligned nanofiber scaffolds. This study demonstrates that electrospun P(LLA-CL)/collagen nanoyarn is a novel, 3D, macroporous, aligned scaffold that has potential application in tendon tissue engineering.


Asunto(s)
Colágeno/química , Ensayo de Materiales , Poliésteres/química , Tendones/citología , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Células Cultivadas , Conejos
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