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1.
J Glob Antimicrob Resist ; 36: 167-174, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38141953

RESUMEN

OBJECTIVES: The relationship between antifungal susceptibility and mortality of cryptococcal meningitis (CM) in HIV-negative patients is poorly understood. METHODS: We conducted a retrospective analysis of 1-year follow-up of 200 HIV-negative CM patients with an initial cerebrospinal fluid (CSF) culture for Cryptococcus neoformans. According to the cut-off values of minimum inhibitory concentration (MIC), two groups of five antifungal agents were classified: amphotericin B (AmB), ≤0.5 µg/mL, >0.5 µg/mL; 5-flucytosine (5-FC), ≤4 µg/mL, >4 µg/mL; fluconazole (FLU), ≤4 µg/mL, >4 µg/mL; itraconazole (ITR), ≤0.125 µg/mL, >0.125 µg/mL; and voriconazole (VOR), <0.25 µg/mL, ≥0.25 µg/mL. Comparisons were performed to analyse clinical features, laboratory, modified Rankin Scale (mRS) scores, and CSF findings under different prognosis outcomes in 1-year. RESULTS: All of Cryptococcus neoformans isolates were sensitive to AmB and VOR, most of them were sensitive to 5-FC and FLU (95.5% and 90.5%, respectively) while only 55.0% of them were susceptible to ITR. Minimum inhibitory concentrations of ITR and VOR were significantly related to baseline mRS scores. All-cause mortality was not significantly related to MICs in Cryptococcus neoformans strains. The combination of actual antifungal agents and two groups of the MICs values for antifungal agents had no significant effects on all-cause mortality. CONCLUSION: Most Cryptococcus neoformans isolates were sensitive to AmB, VOR, 5-FC, and FLU. Because of the small number of deaths, we are not able to comment on whether MIC is associated with mortality of CM in HIV-negative patients.


Asunto(s)
Criptococosis , Cryptococcus neoformans , Infecciones por VIH , Meningitis Criptocócica , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Meningitis Criptocócica/tratamiento farmacológico , Meningitis Criptocócica/complicaciones , Meningitis Criptocócica/microbiología , Estudios Retrospectivos , Fluconazol/farmacología , Criptococosis/complicaciones , Criptococosis/tratamiento farmacológico , Criptococosis/microbiología , Anfotericina B/farmacología , Flucitosina/farmacología , Voriconazol/farmacología , Voriconazol/uso terapéutico , Itraconazol/farmacología , Infecciones por VIH/tratamiento farmacológico
2.
Mar Drugs ; 11(10): 3582-600, 2013 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-24084781

RESUMEN

This study was carried out to investigate the protective effects of chitosan nanoparticles (CNP) against hydrogen peroxide (H2O2)-induced oxidative damage in murine macrophages RAW264.7 cells. After 24 h pre-incubation with CNP (25-200 µg/mL) and chitosan (CS) (50-200 µg/mL, as controls), the viability loss in RAW264.7 cells induced by H2O2 (500 µM) for 12 h was markedly restored in a concentration-dependent manner as measured by MTT assay (P < 0.05) and decreased in cellular LDH release (P < 0.05). Moreover, CNP also exerted preventive effects on suppressing the production of lipid peroxidation such as malondialdehyde (MDA) (P < 0.05), restoring activities of endogenous antioxidant including superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) (P < 0.05), along with increasing total antioxidant capacity (T-AOC) (P < 0.05). In addition, pre-incubation of CNP with RAW264.7 cells for 24 h resulted in the increase of the gene expression level of endogenous antioxidant enzymes, such as MnSOD and GSH-Px (P < 0.05). At the same concentration, CNP significantly decreased LDH release and MDA (P < 0.05) as well as increased MnSOD, GSH-Px, and T-AOC activities (P < 0.05) as compared to CS. Taken together, our findings suggest that CNP can more effectively protect RAW264.7 cells against oxidative stress by H2O2 as compared to CS, which might be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries.


Asunto(s)
Quitosano/farmacología , Peróxido de Hidrógeno/farmacología , Macrófagos/efectos de los fármacos , Nanopartículas/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Animales , Células Cultivadas , Glutatión Peroxidasa/metabolismo , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Superóxido Dismutasa/metabolismo
3.
Adv Sci (Weinh) ; 10(23): e2301292, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37316967

RESUMEN

Printing or patterning particle-based liquid metal (LM) ink is a good strategy to overcome poor wettability of LM for its circuits' preparation in flexible and printed electronics. Subsequently, a crucial step is to recover conductivity of LM circuits consisting of insulating LM micro/nano-particles. However, most widely used mechanical sintering methods based on hard contact such as pressing, may not be able to contact the LM patterns' whole surface conformally, leading to insufficient sintering in some areas. Hard contact may also break delicate shapes of the printed patterns. Hereby, an ultrasonic-assisted sintering strategy that can not only preserve original morphology of the LM circuits but also sinter circuits on various substrates of complex surface topography is proposed. The influencing factors of the ultrasonic sintering are investigated empirically and interpreted with theoretical understanding by simulation. LM circuits encapsulated inside soft elastomer are successfully sintered, proving feasibility in constructing stretchable or flexible electronics. By using water as energy transmission medium, remote sintering without any direct contact with substrate is achieved, which greatly protect LM circuits from mechanical damage. In virtue of such remote and non-contact manipulation manner, the ultrasonic sintering strategy would greatly advance the fabrication and application scenarios of LM electronics.

4.
5.
iScience ; 25(12): 105495, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36419853

RESUMEN

Crack control strategies have been proven very useful for enhancing the stretchability of metal film-based stretchable conductors. However, existing strategies often suffer from the drawbacks of complicated preparation and predefined effective directions. Here, we propose a crack compensation strategy for preparing conductors featured with high stretchability by using liquid metal microparticles (LMMPs)-embedded polydimethylsiloxane (PDMS) as the substrate with a thin film of gold (Au) sputtered on the surface. LMMPs can be elongated to connect the cracked Au film upon stretching, which can form a conductive "island-tunnel" (IT) architecture to compensate for the cracks and maintain the conductivity. The high performance of the stretchable conductor is demonstrated by using it as electrodes to record surface electromyography of human brachioradialis and monitor electrocorticography signals of a rat in normal and epileptic states. The developed strategy shows the potential to provide a new perspective for the fabrication of flexible electronics.

6.
Mar Drugs ; 9(6): 1038-1055, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21747747

RESUMEN

The study was conducted to investigate the promoted immune response to ovalbumin in mice by chitosan nanoparticles (CNP) and its toxicity. CNP did not cause any mortality or side effects when mice were administered subcutaneously twice with a dose of 1.5 mg at 7-day intervals. Institute of Cancer Research (ICR) mice were immunized subcutaneously with 25 µg ovalbumin (OVA) alone or with 25 µg OVA dissolved in saline containing Quil A (10 µg), chitosan (CS) (50 µg) or CNP (12.5, 50 or 200 µg) on days 1 and 15. Two weeks after the secondary immunization, serum OVA-specific antibody titers, splenocyte proliferation, natural killer (NK) cell activity, and production and mRNA expression of cytokines from splenocytes were measured. The serum OVA-specific IgG, IgG1, IgG2a, and IgG2b antibody titers and Con A-, LPS-, and OVA-induced splenocyte proliferation were significantly enhanced by CNP (P < 0.05) as compared with OVA and CS groups. CNP also significantly promoted the production of Th1 (IL-2 and IFN-γ) and Th2 (IL-10) cytokines and up-regulated the mRNA expression of IL-2, IFN-γ and IL-10 cytokines in splenocytes from the immunized mice compared with OVA and CS groups. Besides, CNP remarkably increased the killing activities of NK cells activity (P < 0.05). The results suggested that CNP had a strong potential to increase both cellular and humoral immune responses and elicited a balanced Th1/Th2 response, and that CNP may be a safe and efficacious adjuvant candidate suitable for a wide spectrum of prophylactic and therapeutic vaccines.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Quitosano/administración & dosificación , Nanopartículas/administración & dosificación , Ovalbúmina/administración & dosificación , Células TH1/efectos de los fármacos , Células Th2/efectos de los fármacos , Animales , Anticuerpos/inmunología , Línea Celular Tumoral , Quitosano/efectos adversos , Quitosano/inmunología , Femenino , Humanos , Inmunización/métodos , Inmunoglobulina G/inmunología , Interferón gamma/biosíntesis , Interferón gamma/genética , Interleucina-10/biosíntesis , Interleucina-10/genética , Interleucina-2/biosíntesis , Interleucina-2/genética , Células K562 , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Ratones , Ratones Endogámicos ICR , Nanopartículas/efectos adversos , Ovalbúmina/inmunología , Bazo/efectos de los fármacos , Bazo/inmunología , Células TH1/inmunología , Células Th2/inmunología
7.
J Environ Sci (China) ; 23(11): 1808-15, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22432304

RESUMEN

The adsorption properties of Cu(2+)-loaded montmorillonite clays (MMT-Cu) for Escherichia coli K88 as a function of time, bacteria concentrations, pH, ionic strength and temperature were investigated. The results showed that the bacteria adsorption onto MMT-Cu surface reached equilibrium after 90 min. The percentages of E. coli K88 adsorbed onto the surfaces of MMT-Cu and montmorillonite clays (MMT) at equilibrium were 88.9% and 56.5%, respectively. Scanning electron microscopy revealed that a lot of E. coli K88 adhered to the surface of MMT-Cu. The zeta potential of MMT-Cu was relatively high as compared to that of MMT. The adsorptive ability of MMT-Cu for E. coli K88 was higher than that of MMT (P < 0.05). Moreover, pH, ionic strength and temperature produced a strong influence on the extent of E. coli K88 adsorption to surface of MMT-Cu and MMT. The mechanism of adsorption of E. coli onto MMT-Cu may involve electrostatic attraction and physiochemical properties of bacterial cell walls and minerals surfaces.


Asunto(s)
Bentonita/química , Sulfato de Cobre/química , Escherichia coli Enterotoxigénica/aislamiento & purificación , Adsorción , Microscopía Electrónica de Rastreo
8.
Fish Shellfish Immunol ; 28(1): 49-55, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19800009

RESUMEN

The protective efficacy of oral administration of VP28 using Bacillus subtilis as vehicles (rVP28-bs) in shrimp, Fenneropenaeus chinensis, upon challenge with white spot syndrome virus (WSSV) was investigated. The calculated relative percent survival (RPS) value of rVP28-bs fed shrimp was 83.3% when challenged on the 14th day post-administration, which is significantly higher (p < 0.001) than that of the group administered recombinant Escherichia coli over-expressing rVP28 (rVP28-e21). After immunization, activities of phenoloxidase (PO), superoxide dismutase (SOD) and inducible nitric oxide synthase (iNOS) in hemolymph were analyzed. It was found that the supplementation of rVP28-bs into shrimp food pellets resulted in the most pronounced increase of iNOS activity (p < 0.001), but had the least influence on activities of PO and SOD. Besides, in the shrimp orally administered with rVP28-bs, the caspase-3 activity was one-fifth that of the control, though the signs of apoptosis (chromatin margination, nuclear fragmentation and apoptotic bodies) could not be observed by transmission electron microscope (TEM). These results suggest that by oral delivery of rVP28-bs, shrimp showed significant resistance to WSSV and an effect on the innate immune system of shrimp. The remarkably enhanced level of iNOS after rVP28-bs administration might be responsible for antiviral defense in shrimp.


Asunto(s)
Penaeidae/inmunología , Virus del Síndrome de la Mancha Blanca 1/inmunología , Animales , Apoptosis/inmunología , Bacillus subtilis/virología , Caspasa 3/metabolismo , Inmunidad Innata/inmunología , Monofenol Monooxigenasa/metabolismo , Óxido Nítrico Sintasa/metabolismo , Penaeidae/enzimología , Penaeidae/virología , Superóxido Dismutasa/metabolismo
9.
Fish Shellfish Immunol ; 26(5): 685-90, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19268545

RESUMEN

White spot syndrome virus (WSSV) is a highly pathogenic and prevalent virus infecting shrimp and other crustaceans. The potentiality of binary ethylenimine (BEI)-inactivated WSSV against WSSV in crayfish, Procambarus clarkii, was investigated in this study. Efficacy of BEI-inactivated WSSV was tested by vaccination trials followed by challenge of crayfish with WSSV. The crayfish injected with BEI-inactivated WSSV showed a better survival (P<0.05) to WSSV on the 7th and 21st day post-vaccination (dpv) compared to the control. Calculated relative percent survival (RPS) values were 77% and 60% on the 7th and 21st dpv for 2mM BEI-inactivated WSSV, and 63%, 30% on 7th and 21st dpv for 3mM BEI-inactivated WSSV. However, heat-inactivated WSSV did not provide protection from WSSV even on 7th dpv. In the inactivation process WSSV especially their envelope proteins maybe changed as happened to 3mM BEI and heat-inactivated WSSV particles. These results indicate the protective efficacy of BEI-inactivated WSSV lies on the integrity of envelope proteins of WSSV and the possibility of BEI-inactivated WSSV to protect P. clarkii from WSSV.


Asunto(s)
Astacoidea/inmunología , Astacoidea/virología , Inactivación de Virus , Virus del Síndrome de la Mancha Blanca 1/fisiología , Animales , Aziridinas/química , Calor , Análisis de Supervivencia , Factores de Tiempo , Vacunación/veterinaria , Vacunas de Productos Inactivados , Vacunas Virales , Virus del Síndrome de la Mancha Blanca 1/patogenicidad , Virus del Síndrome de la Mancha Blanca 1/ultraestructura
10.
Dis Aquat Organ ; 85(3): 239-43, 2009 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-19750812

RESUMEN

We investigated the effects of Cu2+-loaded silicate (CLS) on the growth performance, microflora of skin, gill and intestine, and intestinal morphology of crucian carp Carassius auratus. A total of 225 native wild crucian carp, with an average initial body weight of 20 g, were randomly divided into 5 treatment groups using 3 replicate tanks of 15 fish per group. The dietary treatments were (1) basal diet, (2) basal diet + CuSO4, (3) basal diet + silicate, (4) basal diet + 0.5% CLS and (5) basal diet + 50 mg kg(-1) chlortetracycline (CTC, purity 98.8%). The trial lasted for 60 d. We found that body weight increased slightly while feed conversion ratio decreased in the CLS-treated group compared with the control groups. The total number of aerobic bacteria counted in the intestine of carp fed the diet supplemented with the CLS (i.e. Vibrio sp. and E. coli), was significantly lower (p = 0.05) compared with the control groups and the CTC-treated fish, while lactobacillus counts were significantly higher (p = 0.05). Lactobacilli counts of the intestine increased significantly (p = 0.05). However, the microflora of the skin and gill was not affected by the addition of CuSO4, silicate, CLS or CTC. The height of the villi in the proximal, mid and distal intestine mucosa of the silicate- and CLS-treated groups was found to be longer (p = 0.05) compared with the villi of the control or the CTC-treated fish. Supplementation with CuSO4 had no effect on the microflora and the intestinal morphology (p = 0.05). These results indicate that CLS had an antibacterial activity in vivo, which may help protect the intestinal mucosa from invasion of pathogenic bacteria and their toxins.


Asunto(s)
Bacterias/efectos de los fármacos , Cobre/farmacología , Dieta/veterinaria , Suplementos Dietéticos , Carpa Dorada , Intestinos/efectos de los fármacos , Silicatos/farmacología , Animales , Bacterias/crecimiento & desarrollo , Cobre/administración & dosificación , Branquias/microbiología , Carpa Dorada/crecimiento & desarrollo , Carpa Dorada/microbiología , Intestinos/microbiología , Distribución Aleatoria , Silicatos/administración & dosificación , Piel/microbiología
11.
Anim Reprod Sci ; 105(3-4): 292-301, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17475421

RESUMEN

The objective of this study was to optimize the protocols for bovine oocytes activation through comparing the effectiveness of different treatments on the activation and subsequent development of oocytes and examining the effects of two combined activation treatments on the blastocyst apoptosis and ploidy. Cumulus-oocyte complexes (COCs) were recovered from abattoir-derived ovaries and matured in vitro. After maturation, cumulus-free oocytes were activated according to the experiment designs. Activated oocytes were cultured in vitro in modified synthetic oviductal fluid (mSOF) medium and assessed for pronuclear formation (15-16 h), cleavage (46-48 h) and development to the blastocyst stage. In Experiment 1, the matured oocytes were treated with single activation agents, including ionomycin (5 microM for 5 min), ethanol (7% for 7 min), calcium ionophore A23187 (5 microM for 5 min) or strontium (10mM for 5h). The pronuclear formation and cleavage rate were higher significantly in ionomycin (39.0 and 30.7%) and ethanol (41.5 and 28.1%) treatment alone compared to other treatments (9.7-25.2 and 11.3-23.7%, respectively, P<0.05). Very low blastocyst rates (3.9-5.3%) resulted which were not significantly different among treatments (P>0.05). For the combined activation treatment (Experiment 2), the same concentrations of ionomycin and ethanol as in Experiment 1 were used in combination with either 6-dimethylaminopurine (6-DMAP, 2.0 mM for 3 h) or cycloheximide (CHX)+cytochalasin B (CB, 10 microg/ml for 3 h). The pronuclear formation, cleavage rate, blastocyst rate and cell number of blastocyst were higher significantly (P<0.05) in ionomycin+6-DMAP treatment (67.1, 69.2, 28.0 and 91.3%, respectively) and ethanol+CHX+CB treatment (68.9, 70.2, 25.5 and 89.3%, respectively) compared to other treatments (11.7-58.1, 10.2-47.1, 1.5-24.2 and 34.2-62.7%, respectively). In Experiment 3, the parthenogenetic blastocysts produced by activation with ionomycin+6-DAMP and ethanol+CHX+CB and in vitro fertilized blastocysts (control group) were examined for apoptosis using a terminal deoxynucleotidyl transferase mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) assay. The ethanol+CHX+CB treatment (7.0%) showed significantly lower blastocyst apoptosis index compared to ionomycin+6-DAMP treatment (9.1%, P<0.05). Furthermore, the chromosomal composition in the parthenotes embryos differed (P<0.05) among treatments. The percentage of haploid parthenotes was higher in ionomycin+6-DMAP treatment than ethanol+CHX+CB treatment. These results suggested that ethanol+CHX+CB treatment was more favorable protocol for parthenogenesis of bovine oocytes.


Asunto(s)
Apoptosis/fisiología , Bovinos/embriología , Desarrollo Embrionario/efectos de los fármacos , Desarrollo Embrionario/fisiología , Oocitos/fisiología , Partenogénesis/fisiología , Adenina/análogos & derivados , Adenina/farmacología , Animales , Apoptosis/efectos de los fármacos , Cicloheximida/farmacología , Citocalasina B/farmacología , Etanol/farmacología , Femenino , Etiquetado Corte-Fin in Situ/veterinaria , Ionomicina/farmacología , Ionóforos/farmacología , Partenogénesis/efectos de los fármacos , Ploidias , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Estroncio/farmacología , Virginiamicina/farmacología
12.
Eur J Cancer ; 43(1): 184-93, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17049839

RESUMEN

Chitosan nanoparticles (CNP), a kind of widely used drug carrier, have shown potent cytotoxic effects on various tumour cell lines in vitro and in vivo. This study sought to evaluate the antitumour effect of CNP on growth of human hepatocellular carcinoma (BEL7402) and the possible mechanisms involved. Cells were grown in the absence and presence of various concentrations of CNP with mean particle size of about 40nm. Cell viability, ultrastructural changes, surface charge, mitochondrial membrane potential, reactive oxygen species (ROS) generation, lipid peroxidation, DNA fragmentation and fatty acid composition were analysed by MTT assay, electron microscopy, zetasizer analysis, flow cytometry, spectrophotometric thiobarbituric (TBA) assays, DNA agarose gel electrophoresis and GC/MS respectively. For in vivo experiments, male BABL/c nude mice were implanted with BEL7402 cells subcutaneously to establish human hepatoma model. Chitosan, saline, and CNP with different mean particle size (40, 70 and 100nm) were administrated by oral administration (1mg/kg body weight). Tumour and body weight were measured, morphologic changes of tumour and liver tissues were studied under electron microscope. In vitro, CNP exhibited high antitumour activities with an IC(50) value of 15.01microg/ml, 6.19microg/ml and 0.94microg/ml after treatment for 24h, 48h and 72h respectively. CNP could induce cell necrosis observed by electron microscope and DNA fragmentation. The antitumour mechanism was mediated by neutralisation of cell surface charge, decrease of mitochondrial membrane potential and induction of lipid peroxidation. The tumour growth inhibitory rates on BEL7402 cells in nude mice treated with chitosan and CNP with different mean particle size (40, 70 and 100nm) were 24.07%, 61.69%, 58.98% and 34.91% respectively. Typical necrotic morphological changes of tumour tissues and no liver abnormalities were found under electron microscope. In this paper, results show a strong antitumour effect of CNP on human hepatoma cell line BEL7402 in vitro and in vivo. These findings suggest that CNP could be a kind of promising agent for further evaluations in the treatment of hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quitosano/uso terapéutico , Neoplasias Hepáticas/terapia , Nanopartículas/uso terapéutico , Animales , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Supervivencia Celular , Degradación Necrótica del ADN , Fragmentación del ADN , Ácidos Grasos/metabolismo , Humanos , Peroxidación de Lípido , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Masculino , Potencial de la Membrana Mitocondrial , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Electrónica , Distribución Aleatoria , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Ultrasonografía
13.
Bioresour Technol ; 98(1): 202-6, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16446085

RESUMEN

The effect of the protein-bound polysaccharide extracted from Glaciecola polaris (PSG) was investigated in vitro in the protection of oxidatively-injured mouse macrophages stressed by tert-butyl hydroperoxide (tbOOH) or by oxidatively modified low-density lipoprotein (Ox-LDL). The results showed that PSG treatments to protect the macrophages from oxidative injury was effective and the macrophage colony-stimulating factor (M-CSF) exhibited some similar effects. It was speculated that both M-CSF and PSG could protect macrophages from oxidative injury. The results suggested that the effects of PSG were associated with its capability of inducing M-CSF expression.


Asunto(s)
Bacterias/metabolismo , Macrófagos Peritoneales/efectos de los fármacos , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/farmacología , Animales , Lipoproteínas LDL/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Estrés Oxidativo , terc-Butilhidroperóxido/farmacología
14.
Anim Reprod Sci ; 100(1-2): 22-31, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16870363

RESUMEN

The present study examined the effect of green tea polyphenols (GTP) during in vitro maturation (IVM) of bovine oocytes on in vitro fertilization (IVF) parameters, intracellular glutathione (GSH) concentration and subsequent embryo development. Cumulus-oocyte complexes were aspirated from the ovaries derived from slaughterhouse and cultured in modified synthetic oviduct fluid (m-SOF) supplemented with 0-25 microM GTP for 24h. After IVM, cumulus-free oocytes were coincubated with frozen-thawed spermatozoa for 15-18 h. Putative embryos were transferred to m-SOF and cultured for 8 days (Experiment 1). In comparison with the absence of GTP, treatment with GTP at a concentration of 15 microM showed a significant increase in the proportion of pronuclear (PN) formation after sperm penetration (65% versus 80%, P<0.05). No significant differences in the rates of sperm penetration and polyspermic fertilization were found among treatments. The cleavage rate at 48 h of in vitro insemination showed no difference in oocytes matured with or without GTP. However, compared to no addition (23.5%), the presence of 15 and 20 microM GTP during IVM significantly (P<0.05) increased the proportion of blastocysts (38.1% and 36.4%) on day 9 of in vitro insemination. A further increase from 20 to 25 microM GTP reduced (P<0.05) the proportion of blastocysts. In Experiment 2, after IVM, oocytes were fixed to analyze the GSH concentration. Compared to no addition, a higher (P<0.05) level of GSH was found in oocytes matured with 15 microM GTP and compared with 15 microM GTP, GSH was low (P<0.05) at 20 and 25 microM GTP. The results suggest that at certain concentrations of GTP (15 microM) in IVM medium has beneficial effects on subsequent embryo development, and is correlated with intracellular GSH level in bovine oocytes.


Asunto(s)
Bovinos , Embrión de Mamíferos/efectos de los fármacos , Embrión de Mamíferos/fisiología , Fertilización In Vitro/veterinaria , Flavonoides/farmacología , Oocitos/efectos de los fármacos , Oocitos/crecimiento & desarrollo , Fenoles/farmacología , Té/química , Animales , Técnicas de Cultivo , Transferencia de Embrión/veterinaria , Femenino , Fertilización In Vitro/efectos de los fármacos , Flavonoides/química , Fenoles/química , Polifenoles
15.
Biol Trace Elem Res ; 119(2): 128-36, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17916936

RESUMEN

The present study was designed to investigate the effects of various cadmium concentrations on porcine growth hormone (GH) secretion in serum and cultured pituitary cells and to explore the possible mechanisms of cadmium toxicity. In feeding trial, 192 barrows (Duroc x Landrace x Yorkshire), with similar initial body weights, were randomly divided into four different treatment groups with three replicates for each treatment. The diets were supplemented for 83 days with 0, 0.5, 5.0, and 10.0 mg/kg cadmium (as CdCl2). For the cell culture trial, dispersed pituitary cells were incubated with graded doses of cadmium (0, 5, 10, 15, or 20 microM) for 24 h. Pigs treated with 10 mg/kg cadmium had significantly decreased serum GH content. 3-(4,5-dimethyl-2-yl)-2,5-diphenyl tetrazolium bromide assay showed that Cd toxicity was dose-dependent. Cell viability was reduced to 50% at 15 microM concentration. Administration of cadmium significantly reduced GH secretion, whereas cellular NO content and inducible nitric oxide synthase activity increased to a certain extent. These findings suggest that the decrease of GH might be related to NO production and to a change of NO signal pathway caused by cadmium.


Asunto(s)
Intoxicación por Cadmio/metabolismo , Hormona del Crecimiento/sangre , Óxido Nítrico/biosíntesis , Hipófisis/metabolismo , Animales , Cloruro de Cadmio/toxicidad , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Hormona del Crecimiento/metabolismo , Masculino , Óxido Nítrico Sintasa de Tipo II/metabolismo , Porcinos
16.
J Zhejiang Univ Sci B ; 8(5): 323-30, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17542060

RESUMEN

This 6-week study was conducted to evaluate the effects of seven different levels of dietary chromium (Cr) (0, 75, 150, 300, 450, 600, and 1 200 ppb Cr) in the form of Cr nanoparticle (CrNano) on growth, body composition, serum hormones and tissue Cr in Sprague-Dawley (SD) rats. Seventy male SD rats (average initial body weight of (83.2+/-4.4) g) were randomly assigned to seven dietary treatments (n=10). At the end of the trial, body composition was assessed via dual energy X-ray absorptiometry (DEXA). All rats were then sacrificed to collect samples of blood, organs and tissues for determination of serum hormones and tissue Cr contents. The results indicated that lean body mass was significantly increased (P<0.05) due to the addition of 300 and 450 ppb Cr from CrNano. Supplementation of 150, 300, 450, and 600 ppb Cr decreased (P<0.05) percent body fat significantly. Average daily gain was increased (P<0.05) by addition of 75, 150, and 300 ppb Cr and feed efficiency was increased (P<0.05) by supplementation of 75, 300, and 450 ppb Cr. Addition of 300 and 450 ppb Cr decreased (P<0.05) the insulin level in serum greatly. Cr contents in liver and kidney were greatly increased (P<0.05) by the addition of Cr as CrNano in the dosage of from 150 ppb to 1 200 ppb. In addition, Supplementation of 300, 450, and 600 ppb Cr significantly increased (P<0.05) Cr content in the hind leg muscle. These results suggest that supplemental CrNano has beneficial effects on growth performance and body composition, and increases tissue Cr concentration in selected muscles.


Asunto(s)
Composición Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Cromo/administración & dosificación , Cromo/farmacocinética , Hormonas/sangre , Nanopartículas/administración & dosificación , Animales , Cromo/química , Relación Dosis-Respuesta a Droga , Masculino , Nanopartículas/ultraestructura , Especificidad de Órganos , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Distribución Tisular
17.
Drug Discov Today ; 11(19-20): 911-6, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16997141

RESUMEN

In vitro display technologies, especially ribosome display, are valuable tools for many applications. In this paper, ribosome display technology and its applications for directed evolution of functional proteins will be reviewed. Ribosome display has great potential for directed evolution of protein stability and affinity, the generation of high-quality libraries by in vitro preselection, the selection of enzymatic activities, and the display of cDNA and random-peptide libraries. Ribosome display is carried out fully in vitro, which overcomes some of the limitations of cell-based display systems. We anticipate that ribosome display will have a great impact on applications in biotechnology, medicine and proteomics.


Asunto(s)
Ingeniería de Proteínas , Ribosomas/metabolismo , Animales , Evolución Molecular Dirigida , Humanos , Proteínas/metabolismo
18.
Toxicon ; 48(2): 221-6, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16846625

RESUMEN

The objective of this work is to optimize the process parameters for detoxification of gossypol in cottonseed meal (CSM) by Candida tropicalis ZD-3 during solid substrate fermentation (SSF). The maximum detoxification efficiency of gossypol was achieved by employing the substrate, which consists of 70% of CSM, 20% of corn flour and 10% of wheat bran. The optimum fermentation conditions for gossypol detoxification are incubation period of 48h, incubation temperature at 30 degrees Celsius, inoculum level 5% v/w, moisture content of solid substrate 50% and pH in nature. Adding minerals solution to CSM substrate benefit fermentation detoxification.


Asunto(s)
Candida tropicalis/metabolismo , Aceite de Semillas de Algodón/metabolismo , Fermentación , Gossypium , Gosipol/metabolismo , Inactivación Metabólica , Alimentación Animal/análisis , Aceite de Semillas de Algodón/química , Microbiología de Alimentos , Gosipol/análisis
19.
Dis Aquat Organ ; 71(2): 175-8, 2006 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-16956066

RESUMEN

The effect of hyperthermia on the development of white spot syndrome virus (WSSV) in the crayfish Procambarus clarkii was studied by competitive PCR. Crayfish were exposed to different temperatures (24 +/- 1 and 32 +/- 1 degrees C) after WSSV injection. No mortality was observed when crayfish were held at 32 +/- 1 degrees C, but mortality reached 100% when crayfish were transferred to 24 +/- 1 degrees C. Competitive PCR showed that viral levels at 32 +/- 1 degrees C remained at 10(5) copies mg(-1) tissue, while at 24 +/- 1 degrees C levels were significantly higher, rising from 10(4) to 10(10) copies mg(-1) tissue. These results suggest that hyperthermia reduces viral replication, but does not eliminate viral particles from WSSV-infected crayfish.


Asunto(s)
Astacoidea/virología , Calor , Replicación Viral/fisiología , Virus del Síndrome de la Mancha Blanca 1/fisiología , Animales , Cartilla de ADN/química , Branquias/virología , Reacción en Cadena de la Polimerasa/métodos , Análisis de Supervivencia , Factores de Tiempo
20.
Biol Trace Elem Res ; 110(3): 251-63, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16845161

RESUMEN

Malondialdehyde (MDA), glutathione (GSH) content, total antioxidant capacity (T-AOC) levels, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione transferase (GST) activities were studied in serum, liver, and kidney of growing pigs after graded doses of cadmium administration in diets. One hundred ninety-two barrows (Duroc x Landrace x Yorkshire), with similar initial body weight 27.67 +/- 1.33 kg, were randomly allotted into 4 different treatments with 3 replications (16 pigs per replication). The treatments received the same basal diet added with 0, 0.5, 5.0, and 10.0 mg/kg cadmium (as CdCl2), respectively. The results showed pigs treated with 10 mg/kg cadmium significantly decreased average daily gain (ADG) (p<0.05) and increased feed/gain ratio (F/G) (p<0.05) compared to the control. In this treatment, the contents of MDA increased significantly (p<0.05), GSH concentrations, T-AOC levels, and the activities of SOD, GSH-PX, and GST decreased significantly (p<0.05). The results indicate 10 mg/kg cadmium could decrease pig antioxidant capacity after extended exposure and cadmium-induced increase lipid peroxidation might not be only the result of the possibility of lower level of GSH but could also be as a result of direct action of cadmium on peroxidation reaction.


Asunto(s)
Antioxidantes/metabolismo , Cadmio/farmacología , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Animales , Glutatión/metabolismo , Riñón/efectos de los fármacos , Riñón/enzimología , Hígado/efectos de los fármacos , Hígado/enzimología , Malondialdehído/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Porcinos
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