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1.
Mol Genet Genomics ; 299(1): 24, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38438804

RESUMEN

The search for probiotics and exploration of their functions are crucial for livestock farming. Recently, porcine-derived lactic acid bacteria (LAB) have shown great potential as probiotics. However, research on the evaluation of porcine-derived LAB as potential probiotics through genomics-based analysis is relatively limited. The present study analyzed four porcine-derived LAB strains (Lactobacillus johnsonii L16, Latilactobacillus curvatus ZHA1, Ligilactobacillus salivarius ZSA5 and Ligilactobacillus animalis ZSB1) using genomic techniques and combined with in vitro tests to evaluate their potential as probiotics. The genome sizes of the four strains ranged from 1,897,301 bp to 2,318,470 bp with the GC contents from 33.03 to 41.97%. Pan-genomic analysis and collinearity analysis indicated differences among the genomes of four strains. Carbohydrate active enzymes analysis revealed that L. johnsonii L16 encoded more carbohydrate active enzymes than other strains. KEGG pathway analysis and in vitro tests confirmed that L. johnsonii L16 could utilize a wide range of carbohydrates and had good utilization capacity for each carbohydrate. The four strains had genes related to acid tolerance and were tolerant to low pH, with L. johnsonii L16 showing the greatest tolerance. The four strains contained genes related to bile salt tolerance and were able to tolerate 0.1% bile salt. Four strains had antioxidant related genes and exhibited antioxidant activity in in vitro tests. They contained the genes linked with organic acid biosynthesis and exhibited antibacterial activity against enterotoxigenic Escherichia coli K88 (ETEC K88) and Salmonella 6,7:c:1,5, wherein, L. johnsonii L16 and L. salivarius ZSA5 had gene clusters encoding bacteriocin. Results suggest that genome analysis combined with in vitro tests is an effective approach for evaluating different strains as probiotics. The findings of this study indicate that L. johnsonii L16 has the potential as a probiotic strain among the four strains and provide theoretical basis for the development of probiotics in swine production.


Asunto(s)
Lactobacillales , Porcinos , Animales , Lactobacillales/genética , Genómica , Agricultura , Antibacterianos , Antioxidantes , Escherichia coli , Carbohidratos
2.
Sci Total Environ ; 918: 170821, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38336077

RESUMEN

There are various types of bacteria inhabiting the intestine that help maintain the balance of the intestinal microbiota. Lactobacillus is one of the important beneficial bacteria and is widely used as a food starter and probiotic. In this study, we investigated the daily fluctuation of the colonic Lactobacillus species and their distribution of antibiotic resistance genes (ARGs) as well as antibiotic susceptibility in pigs. Metagenomic analysis revealed that genus Lactobacillus was one of the most dominant genera in the colon of growing pigs. Rhythmicity analysis revealed that 84 out of 285 Lactobacillus species exhibited rhythmic patterns. Lactobacillus johnsonii and Lactobacillus reuteri were the two most abundant lactobacilli with circadian oscillation, which increased during the day and decreased at night. The profile of the antibiotic resistome was modified over time within 24-h period. Elfamycin resistance genes were the most enriched class found in Lactobacillus. Furthermore, the seven strains of Lactobacillus isolated from the pig intestine mainly exhibited resistance to gentamicin, erythromycin, and lincomycin. The whole genome annotation of four Lactobacillus strains indicated the presence of multiple ARGs, including elfamycin resistance genes, however, the most abundant ARG was optrA in genome of four strains. These results indicate the presence of various Lactobacillus species harboring a large number of ARGs in the swine intestine. This implies that when using animal-derived lactobacilli, it is essential to assess antibiotic resistance to prevent further transmission between animals and the environment.


Asunto(s)
Antibacterianos , Lactobacillus , Animales , Porcinos , Antibacterianos/farmacología , Lactobacillus/genética , Farmacorresistencia Microbiana/genética , Eritromicina , Bacterias/genética , Colon , Genes Bacterianos
3.
Ecotoxicol Environ Saf ; 262: 115312, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37544067

RESUMEN

BACKGROUND: Hyperuricemia has been linked to exposure to certain metals in cross-sectional studies. However, prospective studies evaluating the associations of multiple metal exposures with incident hyperuricemia are scarce. OBJECTIVES: To prospectively investigate the associations of multiple metal/metalloid concentrations with incident hyperuricemia as well as average annual change in uric acid levels in a longitudinal cohort. METHODS: A longitudinal cohort study included 3957 subjects who were free of cardiovascular disease with certain risk factors for cardiovascular disease at baseline. Incident hyperuricemia was ascertained if serum uric acid level was ≥ 420 µmol/L for men and ≥ 360 µmol/L for women during the follow-up visit in 2013. The relationships between 17 single plasma metals/metalloids and incident hyperuricemia were assessed using unconditional logistic regression models. For metals/metalloids significantly related to incident hyperuricemia, we further utilized generalized linear regression models to evaluate their associations with the average annual change in uric acid levels. Finally, we applied the weighted quantile sum (WQS) regression to investigate the joint effects of metals/metalloids on hyperuricemia risk and uric acid changes, and to identify the most significant metals. RESULTS: After adjusting for potential confounders, plasma aluminum, arsenic, barium, lead, strontium, vanadium, and zinc concentrations were positively associated with incident hyperuricemia in both main analyses and sensitivity analyzes. Compared to the lowest quartiles, participants in the highest quartiles had 63 %-125 % higher risks of incident hyperuricemia (all FDR < 0.05). Furthermore, the positive associations of these seven metals with an average annual uric acid increase reinforced the findings. Finally, the WQS analyses showed that plasma metals mixtures were positively associated with the risk of incident hyperuricemia (OR: 1.47; 95 % CI: 1.23, 1.76) and the average annual change in uric acid levels (ß: 3.17; 95 % CI: 2.42, 3.93), and strontium and vanadium were the most heavily weighted metals, respectively. CONCLUSION: Our findings identify aluminum, arsenic, barium, lead, strontium, vanadium, and zinc exposures as independent risk factors for hyperuricemia and provide new insights into the prevention of hyperuricemia.

4.
Sci Total Environ ; 891: 164692, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37290656

RESUMEN

The increasing prevalence of antimicrobial resistance (AMR) poses a significant threat to public health, and the gut microbiota of livestock (e.g., pigs) are considered a crucial reservoir of antibiotic resistance genes (ARGs), contributing to the long-term persistence of AMR. However, there is still a lack of relevant research on the composition and diurnal fluctuation of ARGs, and their correlation with nutrient substrates in the gut of pigs. To address this knowledge gap, we characterized the antibiotic resistome structure, and circadian oscillations in 45 colonic metagenomically sequenced samples, covering 9-time points within 24 h, from growing pigs. We identified 227 unique types of ARGs, which belonged to 35 drug resistance classes. Tetracycline resistance and antibiotic target protection were the most enriched class and mechanism of drug resistance in colon samples, respectively. The relative abundance of ARGs fluctuated over time within 24 h, with the total abundance peaking at T21 (sampling time at 21:00 p.m.) and the total numbers reaching the peak at T15. A total of 70 core ARGs were identified, which contributed to 99 % of all ARGs. Rhythmicity analysis revealed that 50 out of 227 ARGs and 15 of 49 mobile genetic elements (MGEs) exhibited rhythmic patterns. TetW was the most abundant ARG with circadian rhythm frequently found in Limosilactobacillus reuteri. The concentration of ammonia nitrogen in the colon was significantly correlated with the host genera of rhythmic ARGs. Partial least squares path modeling (PLS-PM) analysis indicated that rhythmic ARGs were significantly correlated with bacterial community, MGEs, and colonic ammonia nitrogen. This study provides new insight into the diurnal fluctuation of ARG profiles in the colon of growing pigs, which was likely driven by the dynamic change of the availability of colonic nutrients substrates.


Asunto(s)
Antibacterianos , Genes Bacterianos , Porcinos , Animales , Antibacterianos/análisis , Amoníaco , Bacterias/genética , Farmacorresistencia Microbiana/genética
5.
Phytopathology ; 113(1): 6-10, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35906769

RESUMEN

The development of full-length infectious cDNA clones for plant RNA viruses is important for studying their molecular biological characteristics, functional genomics, pathogenesis, and vectorization applications. Citrus mosaic virus (CiMV), a member of the genus Sadwavirus, is of economic importance to the citrus industry and comprises a bipartite, positive-sense, single-stranded RNA genome encapsidated in icosahedral virions. In the present study, full-length cDNA clones of CiMV RNA1 and RNA2 were constructed based on a ternary yeast-Escherichia coli-Agrobacterium tumefaciens shuttle vector, pTY, using transformation-associated recombination (TAR) strategy. Infectivity of cDNA clones of CiMV RNA1 and RNA2 was examined in multiple citrus varieties via Agrobacterium-mediated vacuum-infiltration (AVI) through symptom observation, RT-PCR, and virion detection with an electron microscope. Furthermore, the genome-sized RT-PCR fragments of RNA1 and RNA2 were obtained from symptomatic Jinchengyou (Citrus grandis) plants infected by the cloned virus (CiMV211). In addition, CiMV211 produced typical symptoms of wild-type CiMV in cowpea (Vigna angularis) plants inoculated by Agrobacterium-mediated injection. This is the first report of infectious cDNA clones of CiMV, which may lay the foundation for research on the pathogenesis and vectorization of the virus.


Asunto(s)
Citrus , Virus del Mosaico , Virus de Plantas , Plantones/genética , ADN Complementario/genética , Citrus/genética , Vacio , ARN Viral/genética , Enfermedades de las Plantas , Virus del Mosaico/genética , Agrobacterium tumefaciens/genética , Virus de Plantas/genética , Plantas/genética , Células Clonales
6.
Molecules ; 29(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38202798

RESUMEN

Oxidative stress is caused by an imbalance between reactive oxygen species and antioxidant levels. Current research suggests that oxidative stress is one of the key factors in the development of many chronic diseases, and it has been a concern for many years. Many natural compounds have been studied for their special free-radical-scavenging properties. The major chemical constituents of the leaves of Diospyros kaki are flavonoids and triterpenoids, both of which are potential antioxidants that can prevent damage caused by reactive oxygen species or reactive nitrogen species and ameliorate diseases associated with oxidative stress. In addition to the major constituents such as flavonoids and triterpenoids, the leaves of Diospyros kaki include compounds such as phenylpropanoids, alkaloids, phenolic acids, and terpenes. Studies have shown these compounds have certain antioxidant and neuroprotective activities. Experiments have shown that flavonoids or the extracts from the leaves of Diospyros kaki have a variety of good pharmacological activities, which could activate oxidative stress and mitochondrial apoptosis, inhibit the proliferation of human prostate cancer cells and induce apoptosis. It also could achieve the effect of anti-cancer cell proliferation and induce apoptosis by regulating oxidative stress. The main chemical substance of the leaves of Diospyros kaki regulating oxidative stress may be these multi-hydroxyl structure compounds. These natural products exhibit significant antioxidant activity and are an important basis for the leaves of Diospyros kaki to treat human diseases by regulating oxidative stress. This review summarizes the structural types of natural products in the leaves of Diospyros kaki and elaborates the mechanism of the leaves of Diospyros kaki in neuroprotection, anti-diabetes, renal protection, retinal degenerative diseases, and anti-cancer from a new perspective of oxidative stress, including how it supplements other pharmacological effects. The chemical constituents and pharmacological effects of the leaves of Diospyros kaki are summarized in this paper. The relationship between the chemical components in the leaves of Diospyros kaki and their pharmacological effects is summarized from the perspective of oxidative stress. This review provides a reference for the study of natural anti-oxidative stress drugs.


Asunto(s)
Productos Biológicos , Diospyros , Triterpenos , Humanos , Masculino , Antioxidantes/farmacología , Especies Reactivas de Oxígeno , Estrés Oxidativo , Efedrina , Flavonoides/farmacología , Triterpenos/farmacología
7.
Biosensors (Basel) ; 12(11)2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36354483

RESUMEN

Herein, a paper-based glucose/air biofuel cell (BFC) was constructed and implemented for self-powered pesticide detection. Our developed paper-based chip relies on a hollow-channel to transport fluids rather than capillarity, which reduces analysis times as well as physical absorption. The gold nanoparticles (Au NPs) and carbon nanotubes (CNTs) were adapted to modify the paper fibers to fabricate the flexible conductive paper anode/cathode electrode (Au-PAE/CNT-PCE). Molecularly imprinted polymers (MIPs) using 2,4-dichlorophenoxyacetic acid (2,4-D) as a template were synthesized on Au-PAE for signal control. In the cathode, bilirubin oxidase (BOD) was used for the oxygen reduction reaction. Based on a competitive reaction between 2,4-D and glucose-oxidase-labeled 2,4-D (GOx-2,4-D), the amount of GOx immobilized on the bioanode can be simply tailored, thus a signal-off self-powered sensing platform was achieved for 2,4-D determination. Meanwhile, the coupling of the paper supercapacitor (PS) with the paper-based chip provides a simple route for signal amplification. Combined with a portable digital multi-meter detector, the amplified signal can be sensitively readout. Through rational design of the paper analytical device, the combination of BFC and PS provides a new prototype for constructing a low-cost, simple, portable, and sensitive self-powered biosensor lab-on-paper, which could be easily expanded in the field of clinical analysis and drug delivery.


Asunto(s)
Fuentes de Energía Bioeléctrica , Técnicas Biosensibles , Nanopartículas del Metal , Nanotubos de Carbono , Plaguicidas , Polímeros Impresos Molecularmente , Oro , Electrodos , Glucosa , Ácido 2,4-Diclorofenoxiacético
8.
Environ Int ; 169: 107511, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36095929

RESUMEN

BACKGROUND: Metals in the human body represent both environmental exposure and nutritional status. Little is known about the miRNA signature in relation to circulating metals in humans. OBJECTIVES: To characterize metal-associated miRNAs in leukocytes, individually and collectively as networks. METHODS: In a panel of 160 Chinese adults, we measured 23 metals/metalloids in plasma, and sequenced miRNAs and mRNAs in leukocytes. We used linear regression to model the associations between ln-transformed metal concentrations and normalized miRNA levels adjusting for potential confounders. We inferred the enriched leukocyte subtypes for the identified miRNAs using an association approach. We utilized mRNA sequencing data to explore miRNA functions. We also constructed modules to identify metal-associated miRNA networks. RESULTS: We identified 55 metal-associated miRNAs at false discovery rate-adjusted P < 0.05. In particular, we found that lead, nickel, and vanadium were positively associated with potentially lymphocyte-enriched miR-142-3p, miR-150-3p, miR-28-5p, miR-361-3p, and miR-769-5p, and were inversely associated with potentially granulocyte-enriched let-7a/c/d-5p and miR-1294. Interestingly, the five lymphocyte-enriched miRNAs inhibited, whereas miR-1294 activated, ROS and DNA repair pathways. We further confirmed the findings using oxidative damage biomarkers. Next, we clustered co-expressed miRNAs into modules, and identified four miRNA modules that were associated with different metals. The identified modules represented miRNAs enriched in different leukocyte subtypes, and were involved in biological processes including hematopoiesis and immune response, mitochondrial functions, and response to the stimulus. CONCLUSIONS: At commonly exposed low levels, circulating metals were associated with distinct miRNA signatures in leukocytes. The identified miRNAs, individually or as regulatory networks, may provide a mechanistic link between metal exposure and pathophysiological changes in the immune system.


Asunto(s)
Metaloides , MicroARNs , Adulto , Biomarcadores , China , Perfilación de la Expresión Génica , Humanos , Leucocitos , MicroARNs/genética , Níquel , ARN Mensajero/genética , Especies Reactivas de Oxígeno , Vanadio
9.
Plant Dis ; 106(3): 828-834, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34645307

RESUMEN

Citrus yellow vein clearing virus (CYVCV), a new member of the genus Mandarivirus in the family Alphaflexiviridae, is the causal agent of citrus yellow vein clearing disease. CYVCV is transmitted to citrus by Dialeurodes citri, grafting, and contaminated knife blades, threatening citrus production. In this study, four infectious full-length complementary DNA clones of CYVCV (namely AY112, AY132, AY212, and AY221) derived from CYVCV isolate AY were obtained through yeast homologous recombination and inoculated to 'Eureka' lemon (Citrus limon Burm. f.) by Agrobacterium-mediated vacuum infiltration. Pathogenicity analysis indicated that the clones AY212 and AY221 caused more severe symptoms than AY112 and AY132. Northern blot and quantitative reverse transcription PCR analyses showed that the titers of virulent clones (AY212 and AY221) were significantly higher than those of attenuated clones (AY112 and AY132) in the infected 'Eureka' lemon seedlings. Subsequent comparative studies of viral infectivity, accumulation, and symptoms induced by AY221 in nine citrus cultivars indicated that the infectivity of AY221 varied from 25 to 100% between cultivars; 'Oota' ponkan (C. reticulata L.) showed the lowest infection rate, with mild symptoms, which might be a useful resource for CYVCY-resistance genes; and CYVCV titer was positively associated with the symptom development in infected citrus seedlings. In general, this report revealed the biological properties of CYVCV, thus laying a foundation for further investigation of pathogenic mechanisms in this virus.


Asunto(s)
Citrus , Flexiviridae , ADN Complementario , Flexiviridae/genética , Enfermedades de las Plantas , Plantones/genética
10.
Environ Sci Pollut Res Int ; 27(21): 26066-26078, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32358744

RESUMEN

It is of great importance to determine the risk grades of the leakage and non-leakage cases of concentrated saltwater from an underground reservoir for the safe operation of reservoirs and environmental protection. In this paper, the model of risk evaluation for environmental pollution of an underground reservoir stored with concentrated saltwater is established. Moreover, the effects of different influencing factors on the risk grades are investigated, along with an uncertainty analysis. In addition, the risk grade of Lingxin Mining Area is calculated, which can contribute to the prevention and control of pollution in the future for that area. The results show that the water quality complexity of mine water is the most significant indicator for risk grade determination. The certainty of weak-risk grade for environmental pollution caused by an underground reservoir when there is no leakage is more than 60% in the Lingxin Mining Area, and the risk grade becomes a strong-risk grade rapidly after concentrated saltwater leakage is considered. This research can provide a theoretical basis for risk control and management of underground reservoirs storing concentrated saltwater.


Asunto(s)
Minas de Carbón , Agua Subterránea , Carbón Mineral , Monitoreo del Ambiente , Minería , Agua , Calidad del Agua
11.
J Biomol Struct Dyn ; 38(7): 2029-2037, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31157597

RESUMEN

Ferulic acid (FA), a dietary phenolic acid compound, is proved to possess numerous biological activities. Hence, this study was devoted to explore the interaction between FA and calf thymus DNA (ctDNA) by UV - vis absorption, fluorescence, circular dichroism (CD) spectroscopy combined with multivariate curve resolution-alternating least-squares (MCR - ALS) and molecular docking studies. The concentration curves and the pure spectra of compositions (FA, ctDNA and FA - ctDNA complex) were obtained by MCR - ALS approach to verify and monitor the interaction of FA with ctDNA. The groove binding mode between FA and ctDNA was confirmed by the results of melting analysis, viscosity measurements, single-stranded DNA experiments, and competitive studies. The binding constant of FA - ctDNA complex was 4.87 × 104 L mol-1 at 298 K. The values of enthalpy (ΔH°) and entropy (ΔS°) changes in the interaction were -16.24 kJ mol-1 and 35.02 J mol-1 K-1, respectively, indicating that the main binding forces were hydrogen bonds and hydrophobic interactions. The result of CD spectra suggested that a decrease in right-handed helicity of ctDNA was induced by FA and the DNA conformational transition from the B-form to the A-form. The results of docking indicated that FA binding with ctDNA in the minor groove. These findings may be conducive to understand the interaction mechanism of FA with ctDNA and the pharmacological effects of FA. Communicated by Ramaswamy H. Sarma[Formula: see text].


Asunto(s)
ADN , Dicroismo Circular , Ácidos Cumáricos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Termodinámica
12.
Polymers (Basel) ; 11(9)2019 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-31527475

RESUMEN

To improve the adsorption selectivity towards hexavalent chromium anion (Cr(VI)), surface Cr(VI)-imprinted polypropylene (PP) fibers were fabricated by the plasma-mediated grafting strategy. Hence, a non-thermal Rradio frequency discharge plasma irradiation followed by a gaseous phase grafting was used to load acrylic acid (AA) onto PP fibers, which was afterwards amidated with triethylenetetramine and subjected to imprinting with a Cr(VI) template. The plasma irradiation conditions, i.e., gas species, output power, pressure, and time, were optimized and then the influence of grafting time, pressure, and temperature on the grafting degree of AA was investigated. Scanning electron microscopy and Fourier transform infrared spectroscopy were used for the characterization of pristine and modified fibers and to confirm the synthesis success. The hydrophilicity of modified fibers was greatly improved compared with pristine PP fibers. The adsorption thermodynamics and kinetics of Cr(VI) were investigated, as well as the elution efficiency and reusability. The prepared imprinted fibers showed superior adsorption selectivity to Cr(VI) compared with non-imprinted fibers. Finally, the stability of the imprinted fibers against the oxidation ability of Cr(VI) is discussed.

13.
Drug Des Devel Ther ; 11: 3065-3075, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29118572

RESUMEN

PURPOSE: Methotrexate is widely used in chemotherapy for a variety of malignancies. However, severe toxicity, poor pharmacokinetics, and narrow safety margin of methotrexate limit its clinical application. The aim of this study was to develop sustained-release methotrexate-loaded implants and evaluate antitumor activity of the implants after intratumoral implantation. MATERIALS AND METHODS: We prepared the implants containing methotrexate, poly(D,L-lactide-co-glycolide), and polyethylene glycol 4000 with the melt-molding technique. The implants were characterized with regards to drug content, morphology, in vitro, and in vivo release profiles. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were carried out to investigate the physicochemical properties of the implants. Furthermore, the antitumor activity of the implants was tested in a sarcoma 180 mouse model. RESULTS: The implants were prepared as solid rods. Scanning electron microscopy images showed a smooth surface of the implant, suggesting that methotrexate was homogeneously dispersed in the polymeric matrix. The results of DSC and FTIR indicated that no significant interaction between methotrexate and the polymer was observed in the implants. Both in vitro and in vivo release profiles of the implants were characterized by burst release followed by sustained release of methotrexate. Intratumoral implantation of methotrexate-loaded implants could efficiently delay tumor growth. Moreover, an increase in the dose of implants led to a higher tumor suppression rate without additional systemic toxicity. CONCLUSION: These results demonstrate that methotrexate-loaded implants had significant antitumor efficacy in a sarcoma 180 mouse model without dose-limiting side effects, and suggest that the implants could be potentially applied as an intratumoral delivery system to treat cancer.


Asunto(s)
Antineoplásicos/farmacología , Portadores de Fármacos/química , Metotrexato/farmacología , Sarcoma 180/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/toxicidad , Rastreo Diferencial de Calorimetría , Preparaciones de Acción Retardada , Sistemas de Liberación de Medicamentos , Implantes de Medicamentos , Liberación de Fármacos , Femenino , Ácido Láctico/química , Masculino , Metotrexato/administración & dosificación , Metotrexato/toxicidad , Ratones , Microscopía Electrónica de Rastreo , Polietilenglicoles/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Wistar , Sarcoma 180/patología
14.
Drug Deliv ; 24(1): 765-774, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28475414

RESUMEN

Etoposide is widely used in the chemotherapy of a variety of malignancies. But the strong lipophilicity, poor bioavailability, and severe side effects of etoposide limit its clinical application. The aim of this study was to develop sustained-release etoposide-loaded implants and evaluate antitumor activity of the implants after intratumoral implantation. We prepared the implants containing etoposide, poly(L-lactid acid) and polyethylene glycol 4000 by the direct compression method. The implants were characterized regarding drug-excipient compatibility, content uniformity, morphology, sterility, in vitro, and in vivo release profiles. Then the antitumor activity of the implants was tested in xenograft model of A549 human non-small cell lung cancer. SEM images displayed smooth surface of the implant and indicated that etoposide was homogeneously dispersed in the polymeric matrix. The results of content uniformity met the requirements of the Chinese Pharmacopoeia. Both in vitro and in vivo release profiles of the implants were characterized by high burst release followed by sustained release of etoposide. Intratumoral implantation of etoposide-loaded implants could efficiently delay the tumor growth. Furthermore, increasing the dose of implants led to higher tumor suppression rate without adding systemic toxicity. These results indicated that etoposide-loaded implants have significant antitumor efficacy in xenograft model without dose-limiting side effects and they possess a strong potential to be used as an intratumoral chemotherapy option for lung cancer treatment.


Asunto(s)
Neoplasias Pulmonares , Células A549 , Antineoplásicos Fitogénicos , Etopósido , Excipientes , Humanos , Polietilenglicoles , Polímeros
15.
Int J Biol Macromol ; 101: 736-746, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28356236

RESUMEN

In this study, the interaction between di-(2-ethylhexyl) phthalate (DEHP) and calf thymus DNA (ctDNA) was investigated by a combination of multispectroscopic methods, chemometrics algorithm, cyclic voltammetry and molecular simulation. The concentration profiles of the components obtained from resolving the UV-vis absorption data by multivariate curve resolution-alternating least-squares (MCR-ALS) provided a basic evidence for the formation of DEHP-ctDNA complex. Furthermore, the groove binding of DEHP to ctDNA was evidenced by the results from iodide quenching effect, single-stranded DNA quenching effect, melting studies, viscosity measurements and cyclic voltammetry. The binding constant of the complex was in the order of magnitudes of 104Lmol-1, and hydrophobic forces were inferred to drive the binding process. Analysis of Fourier transform infrared spectra suggested that DEHP preferentially bound to A-T rich region of ctDNA in the minor groove, and these results further confirmed by molecular docking. The circular dichroism spectra indicated that DEHP induced a decrease in base stacking degree and an increase in right-handed helicity of ctDNA, but did not cause a significant damage in DNA. This study may improve the understanding of interaction between DEHP and ctDNA and help evaluate the toxicological effect of DEHP.


Asunto(s)
ADN/química , ADN/metabolismo , Dietilhexil Ftalato/metabolismo , Animales , Bovinos , División del ADN/efectos de los fármacos , Dietilhexil Ftalato/química , Dietilhexil Ftalato/farmacología , Electroquímica , Modelos Moleculares , Conformación de Ácido Nucleico , Concentración Osmolar , Termodinámica
16.
Am J Transl Res ; 8(9): 3955-3962, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27725875

RESUMEN

Biliary complications remain a major source of morbidity in liver transplant patients. Among these complications, nonanastomotic biliary strictures (NAS) are especially common and they are frequently therapy resistant in part because biliary epithelial cells are more sensitive to warm ischemic injury than hepatocytes. It has been a challenge to maintain the physiological function of biliary epithelial cells during liver transplantation. In this work, we have examined the effect of oxygen on proliferation of biliary epithelial cells in the rat livers obtained from donation after circulatory death (DCD). Twelve rat livers from DCD were divided into two groups. Livers in the control group were isolated following a standard procedure without oxygen supply. Livers in the experimental group were isolated with a constant supply of oxygen. All livers were then connected to an ex situ liver culture system in the presence of bromodeoxyuridine (BrdU), a thymidine analogue and a marker for cell proliferation. After 6 hours of normothermic ex situ liver culture, morphology and DNA replication in hepatocytes and biliary epithelial cells were assessed and compared between the two groups. We found that about 4.5% of the biliary epithelial cells in the experimental group proliferated compared with only 0.4% of cells in the control based on BrdU staining. No significant change in cell morphology was observed in those cells between the two groups. Thus, our results indicate that oxygen supply is required for maintenance of the physiological function of biliary epithelial cells during liver transplant and suggest that a constant oxygen supply during liver isolation along with ex situ liver organ culture can enhance the repair of biliary epithelial cell injury during liver transplantation.

17.
Cornea ; 35(11): 1483-1487, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27362882

RESUMEN

PURPOSE: To report the presence of normal limbal epithelium detected by in vivo confocal laser scanning microscopy (IVCM) in 3 cases of clinically diagnosed total limbal stem cell deficiency (LSCD). METHODS: This is a retrospective case report consisting of 3 patients who were diagnosed with total LSCD based on clinical examination and/or impression cytology. Clinical data including ocular history, presentation, slit-lamp examination, IVCM, and impression cytology were reviewed. RESULTS: The etiology was chemical burn in 3 cases. One patient had 2 failed penetrating keratoplasties. Another had allogeneic keratolimbal transplantation, but the graft failed 1 year after surgery. The third patient had failed amniotic membrane transplantation. These 3 patients presented with signs of total LSCD including the absence of normal Vogt palisades, complete superficial vascularization of the peripheral cornea, nonhealing epithelial defects, and corneal scarring. Impression cytology was performed in 2 cases to confirm the presence of goblet cells. However, each patient still had distinct areas of corneal and/or limbal epithelial cells detected by IVCM. CONCLUSIONS: Residual normal limbal epithelial cells could be present in eyes with clinical features of total LSCD. IVCM seems to be a more accurate method to evaluate the degree of LSCD.


Asunto(s)
Enfermedades de la Córnea/diagnóstico , Epitelio Corneal/citología , Limbo de la Córnea/patología , Células Madre/patología , Anciano , Córnea/citología , Epitelio , Femenino , Humanos , Masculino , Microscopía Confocal , Persona de Mediana Edad , Estudios Retrospectivos
18.
Am J Transl Res ; 8(6): 2562-74, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27398140

RESUMEN

UNLABELLED: Liver transplantation is an effective approach to end-stage liver disease. Shortage of donor liver and increased waiting time for liver transplantation necessitate the development of an organ culture system by which livers can be cultured and maintained ex situ for a prolonged period of time. The aim of this work is to test whether cell culture condition in vitro could be used to culture whole livers ex situ without the use of erythrocytes. Twelve castrated male land race/farm young porcine livers were exposed to 30 min warm ischemia and 30 min cold perfusion. Livers were isolated and connected to an Ex situ liver culture system using a standard culture medium RPMI1640 supplied with 10% of fetal bovine serum and sufficient dissolved oxygen under a normothermic condition for 6 hours. Metabolic biomarkers, bile and urea production, hepatic cell viability and histology analysis of biopsies were examined and newly proliferated hepatic cells labeled by BrdU were analyzed after 6 hours ex situ culture. The results from biochemical assays and histology analysis indicate that livers after the organ culture still maintain the full function. CONCLUSIONS: Our data demonstrate that the liver culture system established in this work can be used to culture whole livers ex situ in the absence of erythrocytes.

19.
Cancer Chemother Pharmacol ; 76(3): 525-36, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26183605

RESUMEN

PURPOSE: The aim of this study was to clarify the pharmacokinetic, tissue distribution, hematologic, and histopathologic characteristics of sustained-release cisplatin from implants [CDDP-nanoparticle (NP) implants]. METHODS: Eighteen dogs (six hybrids and twelve beagles) were divided into three groups. In Group A, the six hybrid dogs were intravenously administered 20 mg CDDP via a hind limb vein. In Groups B and C, CDDP-NP implants containing CDDP doses of 40 and 60 mg, respectively, were embedded into the esophageal submucosa of beagles via painless gastroscopy with an endoscopic booster. Graphite frameless atomic absorption spectrophotometry was used to measure total platinum in plasma and tissues at various timepoints. In addition, free platinum levels in Group B were determined using inductively coupled plasma mass spectrometry. Toxicologic evaluation was also conducted. RESULTS: Pharmacokinetic results indicated that the CDDP-NP implant could achieve a smooth pharmacokinetic curve, with the plasma invalid concentration reached after almost 480 h, which is approximately ten times longer than that of standard CDDP (48 h). The peak time, peak concentration, clearance, elimination half-life, area under the curve, volume of distribution at steady state, and mean residence time of Groups B and C were 494 and 211, 0.39 and 0.42, 0.044 and 0.059, 80.11 and 87.70, 44 and 49, 38.8 and 57.9, and 12.29 and 12.39 times those of Group A, respectively (all P < 0.05). The ratio of free/total platinum concentration was 2.0-3.1% in plasma, 14.2% in liver tissue, and 14.3% in kidney tissue. Tissue distribution studies showed that the highest platinum concentrations were found in the esophagus, followed by the kidney and liver. Compared with pre-implantation (day 0), there were no significant differences in most hematological indicators in Groups B and C (P > 0.05). Furthermore, histopathologic examination of the kidneys of dogs from Group C revealed no significant kidney damage. Unlike the intravenous CDDP group (Group A), no animals in the implantation groups showed any clinical signs of toxicity. CONCLUSION: CDDP-NP implants can be used to achieve a smooth pharmacokinetic curve and higher drug concentration, as well as a longer mean residence time at the implantation site, with reduced side effects compared with intravenous CDDP.


Asunto(s)
Antineoplásicos/farmacocinética , Cisplatino/farmacocinética , Esófago/metabolismo , Animales , Antineoplásicos/administración & dosificación , Cisplatino/administración & dosificación , Perros , Implantes de Medicamentos , Esófago/efectos de los fármacos , Distribución Aleatoria , Distribución Tisular
20.
Zhonghua Wei Chang Wai Ke Za Zhi ; 17(9): 881-3, 2014 Sep.
Artículo en Chino | MEDLINE | ID: mdl-25273655

RESUMEN

OBJECTIVE: To compare the associated anastomotic complication of cervical esophagogastric anastomosis between stapled and hand-sewn anastomosis in minimally invasive esophagectomy(MIE). METHODS: Clinical data of 203 patients with esophageal cancer receiving combined thoracoscopic and laparoscopic esophagectomy with anastomosis in the neck in our hospital from January 2010 to November 2013 were retrospectively analyzed. All the patients were divided into stapled group(104 patients) and hand-sewn group(99 patients). The incidence of anastomotic leakage and anastomotic stricture between these two groups were compared. RESULTS: There were no significant differences between two groups in gender, age, body mass index, total protein, albumin, and neoadjuvant chemotherapy(all P>0.05). There was no significant difference between the two groups in the incidence of anastomotic leakage [6/104(5.77%) vs. 3/99(3.03%), P>0.05], while the difference in the incidence of anastomotic stricture was significant [10/104(9.62%) vs. 2/99(2.02%), P<0.05]. The time of anastomosis, dieting and hospital stay was (15.5±5.0) min, (5.0±2.8) d and (18.3±5.9) d in stapled group, which was significantly shorter than (28.0±4.5) min, (5.9±1.2) d and (21.8±4.2) d in hand-sewn group(all P<0.05). CONCLUSION: In the minimally invasive esophagectomy, stapled cervical esophagogastric anastomosis is simple and precise, but it is associated with increased risk of anastomotic stricture, therefore the type of anastomosis should be chosen based on the conditions of the patient.


Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagectomía/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Suturas , Anastomosis Quirúrgica , Fuga Anastomótica/etiología , Constricción Patológica/etiología , Esofagectomía/instrumentación , Humanos , Laparoscopía , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Estudios Retrospectivos , Resultado del Tratamiento
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