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1.
Proc Natl Acad Sci U S A ; 118(16)2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33853942

RESUMEN

Host-derived fatty acids are an important carbon source for pathogenic mycobacteria during infection. How mycobacterial cells regulate the catabolism of fatty acids to serve the pathogenicity, however, remains unknown. Here, we identified a TetR-family transcriptional factor, FdmR, as the key regulator of fatty acid catabolism in the pathogen Mycobacterium marinum by combining use of transcriptomics, chromatin immunoprecipitation followed by sequencing, dynamic 13C-based flux analysis, metabolomics, and lipidomics. An M. marinum mutant deficient in FdmR was severely attenuated in zebrafish larvae and adult zebrafish. The mutant showed defective growth but high substrate consumption on fatty acids. FdmR was identified as a long-chain acyl-coenzyme A (acyl-CoA)-responsive repressor of genes involved in fatty acid degradation and modification. We demonstrated that FdmR functions as a valve to direct the flux of exogenously derived fatty acids away from ß-oxidation toward lipid biosynthesis, thereby avoiding the overactive catabolism and accumulation of biologically toxic intermediates. Moreover, we found that FdmR suppresses degradation of long-chain acyl-CoAs endogenously synthesized through the type I fatty acid synthase. By modulating the supply of long-chain acyl-CoAs for lipogenesis, FdmR controls the abundance and chain length of virulence-associated lipids and mycolates and plays an important role in the impermeability of the cell envelope. These results reveal that despite the fact that host-derived fatty acids are used as an important carbon source, overactive catabolism of fatty acids is detrimental to mycobacterial cell growth and pathogenicity. This study thus presents FdmR as a potentially attractive target for chemotherapy.


Asunto(s)
Ácidos Grasos/metabolismo , Lipogénesis/fisiología , Mycobacterium marinum/metabolismo , Animales , Proteínas Bacterianas/metabolismo , Lipólisis , Metabolismo/fisiología , Modelos Animales , Mycobacterium/metabolismo , Infecciones por Mycobacterium no Tuberculosas/metabolismo , Infecciones por Mycobacterium no Tuberculosas/fisiopatología , Oxidación-Reducción , Factores de Transcripción/metabolismo , Virulencia/fisiología , Pez Cebra/metabolismo , Pez Cebra/microbiología
2.
Plant Dis ; 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36825316

RESUMEN

Jackfruit (Artocarpus heterophyllus) is an important tropical commercial fruit crop grown in Hainan province, China. In recent years, severe jackfruit bronzing disease has been found in 11 cities and counties in Hainan. On average, 80% of trees in a jackfruit orchard are affected once bronzing disease is detected. The disease is characterized by yellow-orange to reddish discoloration of the pulp and rags of infected fruit (Hernández-Morales et al. 2017). Jackfruit bronzing disease has been reported previously in the Philippines (Gapasin et al. 2012), Malaysia (Zulperi et al. 2017), and Mexico (Hernández-Morales et al. 2017). Diseased samples of jackfruit 'Tai Eight' with the bronzing symptoms were collected from a plantation in Changjiang, Hainan. The samples were sterilized with 75% ethanol for 30 s, then soaked with 1% sodium hypochlorite for 8 min, and rinsed with sterilized distilled water. The sterilized tissues were ground in 2 mL sterile water, and allowed to stand for 30 min. Then, 500 µL of the supernatant was spread on Glucose-Yeast agar medium and incubated overnight at 28ºC. Representative bacterial colonies were lemon-yellow, convex and smooth, transparent with entire edges. Colonies were Gram-negative, positive for catalase and gelatin liquefaction, which were consistent with the characteristics of P. stewartii subsp. stewartii. In PCR amplifications, an 920 bp amplicon of strain JTPE2 with the primers ES16/ESIG2c (Coplin et al. 2002) and an 1100 bp amplicon of strain JTPC2 with the primers CPSL1/CPSR2c (Ibrahim et al. 2019) were obtained, whereas no bands were observed for the negative control samples. The ES16/ESIG2c and CPSL1/CPSR2c fragments were sequenced for nucleotide BLAST (BLASTn) searches of the NCBI database and phylogenetic tree construction. The obtained ES16/ESIG2c sequences (SAR accession no. SRR22405292) showed 99.07%-99.60% similarity with P. stewartii subsp. stewartii (CP017581, AJ311838 and MF598163). The obtained CPSL1/CPSR2c sequences (SAR accession no. SRR22405293) showed 99.40%-99.99% similarity with P. stewartii subsp. stewartii (MW971422, MH752485 and MH257287). Phylogenetic analysis based on cpsDE sequences (Ibrahim et al. 2019) using the maximum likelihood method revealed that strains JTPE2 and JTPC2 were clustered together with P. stewartii subsp. stewartii. A pathogenicity test was conducted by injecting 2 mL of 108 CFU/ml bacterial suspension into pulp from healthy, surface-sterilized jackfruit. Pulp injected with sterilized distilled water served as a negative control. All inoculated samples produced bronzing symptoms from 2-3 weeks post-inoculation similar to the field-observed symptoms, whereas control fruit were asymptomatic. The strains were reisolated from symptomatic jackfruit pulp to complete Koch's postulates. The bacterial suspension was inoculated on 2-week-old maize seedlings to supplement in vivo pathogenicity testing. Typical Stewart's disease leaf symptoms were visible at 2 weeks post-inoculation. Based on morphological, biochemical, and physiological evidence, pathogenicity tests, and molecular analyses, the pathogenic bacterium isolated from 'Tai Eight' jackfruit was identified as P. stewartii subsp. stewartii. To our knowledge, this is the first report of bronzing disease caused by P. stewartii subsp. stewartii on jackfruit in China, which may assist in preventing the global spread of jackfruit bronzing disease.

3.
Plant Dis ; 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37079014

RESUMEN

Jackfruit (Artocarpus heterophyllus) is widely cultivated in the tropical areas in the world. Jackfruit bark split disease occurred in the large-scale plantations of 18 cities and counties surveyed in Hainan since 2021, among which the incidence rate of serious orchards reached about 70%, and the mortality rate reached about 35%. Jackfruit bark split disease mainly harms tree branches and trunks, manifested as water stains, bark gumming, bark depression, bark cracking, and ultimately plant death. To identify the pathogen, Four samples with jackfruit bark split disease symptoms were collected, sterilized with 75% ethanol for 30 s, then soaked in 2% sodium hypochlorite (NaClO) for 5 mins, and finally rinsed continuously with sterilized distilled water. The sterilized tissues were placed on LB agar medium and incubated in illumination incubator at 28 ℃. Four milky white, round with neat edges, convex and smooth, translucent colonies were obtained. All isolates (JLPs-1 to JLPs-4) were Gram-negative, negative for oxidase, catalase and gelatin liquefaction. Amplification and sequencing of 16S rDNA gene from 4 isolates were conducted with the universal primers 27f /1492r (Lane et al. 1991). The BLASTn analysis of obtained JLPs-1 and JLPs-3 sequences (GenBank accession nos. OP942452 and OP942453) showed an identity percentage of 98.99% and 98.93% with Pectobacterium sp. (CP104733), respectively. Phylogenetic analysis based on 16S rDNA gene using the neighbor-joining method with MEGA 7.0 software revealed that JLPs-1 and JLPs-3 were clustered together with P. carotovorum reference strains. The four housekeeping genes gyrA, recA, rpoA and rpoS were partially sequenced for JLPs-1 isolates using primers gyrA1/gyrA4, recA1/recA2c, rpoS1/rpoS2 and rpoA F1/rpoA R1 (Loc et al. 2022), respectively. Multilocus sequence analyses identified the isolates from jackfruit as P. carotovorum. To further confirm the identification of Pectobacterium carotovorum, pelY gene, P. carotovorum subsp. Brasiliensis 16S-23S intergenic region (Pcb IGS) and P. carotovorum subsp. carotovorum (Pcc) specific fragment were amplified with primers Y1/Y2 (Darrasse et al. 1994), BR1f/L1r (Duarte et al. 2004) and EXPCCF/EXPCCR (Kang et al. 2003), respectively. A 540 bp target fragment was successfully amplified from JTPs only by EXPCCF/EXPCCR and there no bands for the other two primers. Pathogenicity test was performed in the field, and all the inoculated trees were 2-3-year-old 'Qiong Yin No.1' variety. Dense small holes were pierced with sterilized inoculation needle on four healthy jackfruit trees. Then punctured wounds were spraying-inoculated with bacteria suspension of JLPs-1 (108 CFU/ml), and finally wrapped with plastic wrap to moisturize. Two trees inoculated with sterile distilled water served as negative control. Typical symptoms of bark gumming, bark depression, bark cracking were observed on all of the inoculated trees at 17 dpi which just similar to those originally caused by P. carotovorum in the field, whereas negative control trees remained asymptomatic. The strains were re-isolated successfully from symptomatic jackfruit trees and were consistent with the biological and molecular biological characteristics of original strains, confirming that the pathogen of jackfruit bark split disease was Pectobacterium carotovorum. To our knowledge, this is the first report of P. carotovorum causing bark split disease on jackfruit in China.

4.
Clin Exp Pharmacol Physiol ; 48(1): 147-156, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32860257

RESUMEN

PURPOSE: Keratin 18 (KRT18) is a cytoskeleton protein that plays a key role in multiple cancers. The present study aims to further investigate the roles of KRT18 in gastric cancer (GC) tissues and cells. METHODS: The KRT18 protein expression levels of GC tissues and cells were detected using immunohistochemistry and western blot. The relationship between KRT18 expression levels and the prognosis of GC patients was further analyzed. To explore this relationship, small interfering RNA (siRNA) was used to inhibit the endogenous expression of KRT18 in GC cells. Furthermore, the effects of KRT18 on the proliferation, invasion, migration, and apoptosis of GC cells were analyzed in vitro. In addition, the role of KRT18 in GC-specific processes was investigated. RESULTS: Keratin 18 expression was shown to be up-regulated in GC tissues and associated with poor prognosis. Following KRT18 silencing with siRNA, the proliferation, invasion, and migration ability of GC cells were significantly inhibited, while the apoptotic process was promoted. Furthermore, the activation of the MAPK signalling pathway was identified as the potential mechanism through which KRT18 influenced GC processes. CONCLUSIONS: Keratin 18 plays a cancer-promoting role and might be a potential therapeutic target in the treatment of GC.

5.
Wei Sheng Yan Jiu ; 49(5): 790-794, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-33070826

RESUMEN

OBJECTIVE: To explore the effect of myrica flavone on male reproductive toxicity induced by cyclophosphamide and its mechanism. METHODS: Thirty 6-week-old male ICR mice were randomly divided into 5 groups: blank control group, cyclophosphamide reproductive injury model group, myricetin low-medium high-dose intervention group. Except the blank control group, the other groups were intraperitoneally injected with cyclophosphamide 50 mg/kg daily for 7 consecutive days. The myricetin group received intragastric administration of 100, 200, and 400 mg/kg myricetin daily for 30 consecutive days since the second day of modeling. The blank control group and the model control group were given an equal volume of a 0. 25% sodium carboxymethyl cellulose solution. The body weight was measured every 3 days, and the day after the last administration, the mice were sacrificed by cervical dislocation, and the epididymis and testes were quickly taken. Testicular weighing, testicular index calculation, epididymis to obtain sperm, sperm analyzer to analyze sperm density and vitality. The expression of Bax and Bcl-2 in testicular tissues was detected by immunoblotting, and the mitochondrial membrane potential of sperm was detected by flow cytometry. RESULTS: After 9 days of modeling, the weight of mice in the model group was lower than that of the blank control group, which was statistically different(P<0. 05). There was no difference between the myricetin treatment group and the model group. The testis index of the model group was(3. 93±0. 91)mg/g, which was significantly lower than that of the blank control group(6. 93±0. 98)mg/g, and the difference was statistically significant(P<0. 05). After treatment with bayberry flavonoids, the testis index increased, in the 100 and 200 groups and 400 mg/kg testis index were(3. 94±1. 21) mg/g, (4. 33±0. 88) mg/g, and(4. 80±0. 43) mg/g, respectively. Compared with model control group, The difference was statistically significant(P<0. 05 and P<0. 01). Compared with the control group, the sperm density, sperm rate of forward movement, sperm rate of non-forward movement, and decreased sperm rate of non-moving sperm increased in the model group. After treatment with bayberry flavonoids, compared with the model group, the sperm density, sperm rate of forward motion, and sperm rate of non-forward motion increased, and the immobility sperm rate decreased. The 200 and 400 mg/kg groups had statistical significance(P<0. 05 or P<0. 01); the normal rate of sperm mitochondrial membrane potential in the model group was(54. 70±5. 45)%, and the normal mitochondrial membrane potential rate after treatment with myricetin of 100, 200 and 400 mg/kg(59. 10±9. 97)%, (62. 10±6. 07)% and(77. 10±8. 87)%, of which the 400 mg/kg group was statistically significant(P<0. 05); the ratio of Bax/Bcl-2 in the model group was 5. 92±1. 45, and the ratio of Bax/Bcl-2 decreased after treatment with myricetin of 100, 200 and 400 mg/kg, which were 2. 52±0. 51, 1. 71±0. 52 and 1. 07±0. 29. There were statistical differences(P<0. 05 or P<0. 01). CONCLUSION: Myrica flavone can protect sperm mitochondrial membrane potential, inhibit testicular cell apoptosis, and protect the male mice from reproductive toxicity induced by cyclophosphamide.


Asunto(s)
Flavonoides , Motilidad Espermática , Animales , Ciclofosfamida/toxicidad , Flavonoides/toxicidad , Humanos , Masculino , Ratones , Ratones Endogámicos ICR
6.
Wei Sheng Yan Jiu ; 49(1): 98-131, 2020 Jan.
Artículo en Zh | MEDLINE | ID: mdl-32290922

RESUMEN

OBJECTIVE: To study the effect of curcumin on the expression of glucose regulated protein 78 kD(GRP78) and cysteinyl aspartate specific proteinase-12(caspase-12) of myocardial endoplasmic reticulum stress related factors in type 2 diabetes rats. METHODS: Type 2 diabetes rats model was established by high-fat drink feeding and one-time intraperitoneal injecting streptozotocin(35 mg/kg). After model rats were built, rats was randomly divided into diabetic model group and low dose of curcumin group(200 mg/kg), high dose of curcumin group(400 mg/kg) and captopril group(60 mg/kg) with 10 rats in each group. The rats in each group were ig administered with corresponding drugs once a day. Continuous administration for 12 w. The levels of fasting blood glucose(FBG) and lactate dehydrogenase(LDH), electrocardiogram and heart weight index(HWI) were measured respectively. The myocardial pathological changes were observed by HE staining. The levels of collagen fiber expression in myocardial tissue were performed by Masson staining. The protein expression levels of GRP78 and caspase-12 in myocardium of rats were observed by immunohistochemistry. RESULTS: The result showed that compared with control group, the levels of FBG and LDH of serum were increased obviously, HWI was increased, myocardial cells were hypertrophy, the collagen fibers of intercellular space of cell were increased, the protein expressions of GRP78 and caspase-12 of myocardium were increased in rats, myocardial cell apoptosis was increased in the model group(P<0. 05). Compared with model group, FBG and LDH levels and HWI were reduced, the collagen fiber of intercellular space were decreased, the protein expression levels of GRP78 and caspase-12 were lowered in high dose of curcumin group(P<0. 05). CONCLUSION: It indicates that Cur defends myocardium tissue in type 2 diabetes rats, which may be related to decreasing the level of blood glucose and the protein expressions of GRP78 and caspase-12, and blocking the ERS-initiated apoptotic.


Asunto(s)
Caspasa 12/metabolismo , Curcumina/farmacología , Diabetes Mellitus Tipo 2 , Estrés del Retículo Endoplásmico , Corazón/efectos de los fármacos , Proteínas de Choque Térmico/metabolismo , Animales , Apoptosis , Glucemia , Corazón/fisiopatología , Miocardio , Distribución Aleatoria , Ratas
7.
Inorg Chem ; 56(21): 13329-13336, 2017 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-29035050

RESUMEN

To develop coordination polymers (CPs) as catalysts to selectively catalyze the reaction of C-H bond activation of arylalkanes to their homologous ketones, three new Cu(I)-based coordination polymers (CuI-CPs) [CuI(aas-TPB)]n (1), [CuBr(ass-TPB)CH3CN]n (2), and {[Cu(ass-TPB)]Cl}n (3) (TPB = N,N,N-tris(3-pyridinyl)-1,3,5-benzenetricarboxamide) were synthesized. Structural variations from a herringbone fashion one-dimensional framework of 1 to a two-dimensional framework of 2 containing a 48-membered macrocycle and a cationic three-dimensional framework of 3 filled with Cl- anions were observed arising from the different halogen ions (I-, Br-, and Cl-). 1-3 were used as the green heterogeneous catalysts to catalyze direct C-H bond activation reactions of arylalkanes to ketones under mild reaction conditions with water as solvent. Handy product separation, convenient reaction procedures, and recyclability of these catalysts make the catalytic system fascinating. Moreover, the CuI-CPs performed the reaction with high regioselectivity due to the unique spatial confinement effect of CPs.

8.
J Korean Med Sci ; 32(2): 186-194, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28049228

RESUMEN

The present study developed an oral hepatocyte growth factor (HGF) gene therapy strategy for gastric ulcers treatment. An attenuated Salmonella typhimurium that stably expressed high HGF (named as TPH) was constructed, and the antiulcerogenic effect of TPH was evaluated in a rat model of gastric ulcers that created by acetic acid subserosal injection. From day 5 after injection, TPH (1 × 109 cfu), vehicle (TP, 1 × 109 cfu), or sodium bicarbonate (model control) was administered orally every alternate day for three times. Then ulcer size was measured at day 21 after ulcer induction. The ulcer area in TPH-treated group was 10.56 ± 3.30 mm², which was smaller when compared with those in the TP-treated and model control groups (43.47 ± 4.18 and 56.25 ± 6.38 mm², respectively). A higher level of reepithelialization was found in TPH-treated group and the crawling length of gastric epithelial cells was significantly longer than in the other two groups (P < 0.05). The microvessel density in the ulcer granulation tissues of the TPH-treated rats was 39.9 vessels/mm², which was greater than in the TP-treated and model control rats, with a significant statistical difference. These results suggest that TPH treatment significantly accelerates the healing of gastric ulcers via stimulating proliferation of gastric epithelial cells and enhancing angiogenesis on gastric ulcer site.


Asunto(s)
Factor de Crecimiento de Hepatocito/metabolismo , Salmonella/genética , Úlcera Gástrica/terapia , Administración Oral , Animales , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Terapia Genética , Factor de Crecimiento de Hepatocito/análisis , Factor de Crecimiento de Hepatocito/genética , Humanos , Masculino , Neovascularización Fisiológica , Proteínas Proto-Oncogénicas c-met/metabolismo , Ratas , Ratas Wistar , Úlcera Gástrica/patología , Cicatrización de Heridas
9.
Biomed Chromatogr ; 29(10): 1553-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25808247

RESUMEN

A sensitive and simple liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method for the determination of corilagin in rat plasma has been developed. Samples were prepared with protein precipitation method and analyzed with a triple quadrupole tandem mass spectrometer. We employed negative electrospray ionization as the ionization source and the analytes were detected in multiple reaction monitoring mode. Separation was achieved on a C8 column eluted with mobile phase consisting of methanol-0.1% formic acid in a gradient mode at the flow rate of 0.3 mL/min. The total run time was 7.0 min.This method was proved to have good linearity in the concentration range of 2.5-1000.0 ng/mL. The lower limit of quantification of corilagin was 2.5 ng/mL. The intra- and inter-day relative standard deviationa across three validation runs for four concentration levels were both <9.8%. The relative error was within ±6.0%. This assay offers advantages in terms of expediency and suitability for the analysis of corilagin in rat plasma. The practical utility of this new HPLC-MS/MS method was confirmed in pilot plasma concentration studies in rats following oral administration.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Glucósidos/sangre , Taninos Hidrolizables/sangre , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Administración Oral , Animales , Calibración , Límite de Detección , Masculino , Phyllanthus/química , Extractos Vegetales/administración & dosificación , Extractos Vegetales/sangre , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Zhongguo Zhong Yao Za Zhi ; 40(21): 4240-4, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-27071264

RESUMEN

To investigate the effect of flavonoids from Sophora flavescens in aging mice induced by D-galactose and its mechanism. Totally 60 mice were randomly divided into six groups: the control group, the model group, the piracetam group (positive control group) and flavonoids from S. flavescens low, medium and high doses groups. Except for the control group, all of the rest groups were subcutaneously injected with D-galactose (160 mg x kg(-1)) for successively 30 days to establish the sub-acute senescent model. Meanwhile, flavonoids from S. flavescens low, medium and high doses groups were respectively administered with 150, 300 and 600 mg xkg-('1)of flavonoids from S. flavescens for 30 days. The learning and memory abilities of mice were determined by avoiding darkness ex-eriment and jumping stair experiment. The contents of malondialdehyde (MDA) tumor necrosis factor-aα NF-aα the activities of superoxide dismutase (SOD) monoamine oxidase-B (MAO-B) Na'(+)K'(+)-ATPase and Ca2(+ )-ATPase in the brain of mice were deter-ined respectively after the behavioral experiments. The activity of lactic dehydrogenase ( DH) in blood serum was also determined and analyzed by microscope after HE staining to observe the changes in hippocampal organizational structure. Compared with the model group, flavonoids from S. favescens medium and high doses groups showed significantly increases in the latency of avoiding darkness and jumping stair experiments; flavonoids from S. fllvescens low, medium and high doses groups and the piracetam group showed de-reases in the numbers of errors in avoiding darkness experiment; the flavonoids from S. flavescens high dose group and the piracetam group showed reduction- n the number of errors in jumping stair experiment (P <0 . 5 or P <0 . 1). Flavonoids from S. flavescens me-ium and high doses groups and the piracetam group showed improvements in the activities of SOD, Na'(+)K'(+)ATPase in the brain of mice and declines in the contents of MDA and TNF-aα the activity of MAO-B in the brain of mice, the activity of LDH in blood serum (P <0 . 5 or P <0 . 1). Flavonoids from S. flavescens low, medium and high doses groups and the piracetam group also showed im-rovement in the activity of Ca2(+ )ATPase, with statistical difference from the model group (P <0 . 5 or P <0 . 1). The pathological result showed decreases in the number of cells of hippocampal dentate gyrus area, sparse cell arrangement, incomplete cellular mor-hology, scarce cytoplasm, blurred boundary between nucleus and cytoplasm, nuclei anachromasis, irregular pyknosis and unconspicu-us nucleoli in the model group. Compared with the model group, flavonoids from S. flavescens low, medium and high doses groups and the piracetam group showed improvements in hippocampal organization tissues. Flavonoids from S. favescens can improve the learning and memory ability of senescent mice induced by D-galactose. Its mechanism may be correlated with the enhancement of anti-oxidative actions by lowering TNF-aαcontent, which results in the stability of cell membrane and the reduction in MAO-B activity.


Asunto(s)
Envejecimiento/efectos de los fármacos , Medicamentos Herbarios Chinos/administración & dosificación , Flavonoides/administración & dosificación , Sophora/química , Envejecimiento/metabolismo , Envejecimiento/psicología , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Femenino , Galactosa/efectos adversos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Humanos , Aprendizaje/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Ratones , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
11.
Analyst ; 139(9): 2099-107, 2014 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-24622614

RESUMEN

Improving the detection sensitivity of analytical instruments has been a challenging task for chemometricians since undetectability has been almost unavoidable in trace analysis, even under optimized experimental conditions and with the use of modern instruments. Various chemometrics methods have been developed which attempt to address this detection problem but with limited success (e.g., fast Fourier transform and wavelet transform). However, the application of stochastic resonance (SR) creates an entirely new and effective methodology. Stochastic resonance is a phenomenon which is manifested in non-linear systems where a weak signal can be amplified and optimized with the assistance of noise. In this review, we summarize the use of basic SR, optimization of parameters and its modifications, including periodic modulation stochastic resonance (PSRA), linear modulation stochastic resonance (LSRA), single-well potential stochastic resonance (SSR) and the Duffing oscillator algorithm (DOA) for amplifying sub-threshold small signals. We also review the advantages and the disadvantages of various SR procedures.


Asunto(s)
Cromatografía/métodos , Procesos Estocásticos , Análisis de Fourier , Límite de Detección
12.
Protein Expr Purif ; 90(1): 27-33, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23648869

RESUMEN

Protein transduction domains (PTDs), such as the TAT peptide derived from HIV Tat protein, may transduce macromolecules into cells. In the present study, the TAT peptide-fused artificial transcription factors (ATFs) were generated by fusion of the N-terminal TAT peptide with SV40 promoter-targeted three-fingered C2H2 zinc finger proteins and the KRAB transcriptional repression domain. The fusion proteins were then expressed in an E .coli system and purified by Ni-NTA affinity chromatography. The purified fusion proteins were tested on mammalian cell lines CHO DG44 and L929. TAT-ATF-S, which contains the zinc fingers that bind to the SV40 promoter with high specificity, exhibited the desired transcriptional repression activity to the reported genes, indicating the successful cellular delivery and desired conformation of TAT-ATF-S. Our study has provided a new strategy for intracellular ATF delivery.


Asunto(s)
VIH-1/metabolismo , Proteínas Recombinantes de Fusión/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/genética , Animales , Sitios de Unión , Células CHO , Cricetinae , Cricetulus , Productos del Gen tat/genética , VIH-1/genética , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Dedos de Zinc , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismo
13.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 42(2): 184-91, 2013 03.
Artículo en Zh | MEDLINE | ID: mdl-23585005

RESUMEN

OBJECTIVE: To investigate the role of phospholipase C(PLC) in cytoskeleton rearrangement of mouse dendritic cells invaded by Mycobacterium tuberculosis. METHODS: Mouse dendritic DC2.4 cells were co-cultured with Mycobacterium tuberculosis H37Rv. F-actin of DC2.4 cells were strained with phalloidin-TRITC, the microtubule was stained with anti-ß-tubulin monoclonal antibody and FITC-conjugated AffiniPure anti-mouse IgG. The changes of cytoskeleton in DC2.4 cells induced by Mycobacterium tuberculosis H37Rv were determined by fluorescence microscopy and the rates of F-actin rearrangements were calculated. The expressions of PLC in cytoplasm and cytomembrane of DC2.4 cells were measured by ELISA. DC2.4 cells were pretreated with PLC inhibitor U73122, then F-actin rearrangements induced by invasion of Mycobacterium tuberculosis were observed. RESULTS: Bacterial invasion was observed while DC2.4 cells were co-incubated with Mycobacterium tuberculosis H37Rv for 2 h. The rates of invasion were (26.1 ± 4.5)%, (39.9 ± 5.6)%, (51.2 ±5.9)%, (57.9 ± 6.1)% and (63.9 ± 6.8)% at 4, 6, 8, 10 and 12 h of co-culture, respectively; while those were (13.6 ± 3.1)%, (14.2 ± 3.9)%, (15.1 ± 4.3)%, (16.8 ± 4.0)% and (18.3 ± 5.2)% after blocked by PLC, respectively. The rates of the F-actin rearrangements at 2, 4, 6, 8, 10 and 12 h after DC2.4 cells were invaded by H37Rv were (26.9 ± 1.5)%, (59.3 ± 2.8)%, (72.7 ± 4.8)%, (78.2 ± 5.9)%, (63.3 ± 2.9)% and (43.2 ± 2.6)%, respectively; while those were (18.5 ± 1.2)%, (22.3 ± 1.7)%, (3.6 ± 2.5)%, (24.8 ± 2.3)%, (22.3 ± 1.3)% and (23.8 ± 1.8)% after blocked by PLC, respectively. There were no changes of the microtubule observed in DC2.4 cells at the same time points. The rates of the F-actin rearrangements before blocked by PLC were higher than those after PLC blockade at 4, 6, 8 and 10 h (P <0.05). The expressions of PLC in cytomembrane in DC2.4 cells increased after 2 h and reached its highest level at 8 h. The PLC inhibitor U73122 inhibited the expressions of PCL in cytomembrane of DC2.4 cells, but not in cytoplasm. CONCLUSION: Mycobacterium tuberculosis can provoke to F-actin rearrangements through PLC molecule, which would further lead to Mycobacterium tuberculosis invasion of DC2.4 cells.


Asunto(s)
Citoesqueleto/metabolismo , Células Dendríticas/citología , Mycobacterium tuberculosis/patogenicidad , Fosfolipasas de Tipo C/metabolismo , Actinas/metabolismo , Animales , Línea Celular , Técnicas de Cocultivo , Células Dendríticas/microbiología , Ratones , Microtúbulos/metabolismo
14.
Front Med (Lausanne) ; 10: 1167452, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37425304

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become the most common coronavirus that causes large-scale infections worldwide. Currently, several studies have shown that the ABO blood group is associated with coronavirus disease 2019 (COVID-19) infection and some studies have also suggested that the infection of COVID-19 may be closely related to the interaction between angiotensin-converting enzyme 2 (ACE2) and blood group antigens. However, the relationship between blood type to clinical outcome in critically ill patients and the mechanism of action is still unclear. The current study aimed to examine the correlation between blood type distribution and SARS-CoV-2 infection, progression, and prognosis in patients with COVID-19 and the potential mediating role of ACE2. With 234 patients from 5 medical centers and two established cohorts, 137 for the mild cohort and 97 for the critically ill cohort, we found that the blood type A population was more sensitive to SARS-CoV-2, while the blood type distribution was not relevant to acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), and mortality in COVID-19 patients. Further study showed that the serum ACE2 protein level of healthy people with type A was significantly higher than that of other blood groups, and type O was the lowest. The experimental results of spike protein binding to red blood cells also showed that the binding rate of people with type A was the highest, and that of people with type O was the lowest. Our finding indicated that blood type A may be the biological marker for susceptibility to SARS-CoV-2 infection and may be associated with potential mediating of ACE2, but irrelevant to the clinical outcomes including ARDS, AKI, and death. These findings can provide new ideas for clinical diagnosis, treatment, and prevention of COVID-19.

15.
Clin Cardiol ; 46(12): 1569-1577, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37711064

RESUMEN

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a common cardiac genetic disorder that clinically manifests with sudden death and progressive heart failure. Moreover, thyroid dysfunction is associated with increased cardiovascular morbidity and mortality risks. Therefore, this study aimed to clarify whether thyroid hormones could serve as an independent predictor of adverse events in patients with HCM. METHODS: The cohort consisted of 782 patients with HCM who had thyroid hormones baseline data and were admitted to the Affiliated Hospital of Jiaxing University. Patients were divided into two groups according to serum levels of free triiodothyronine (fT3): the normal fT3 and low triiodothyronine (T3) syndrome groups. Low T3 syndrome was defined as fT3 < 2.43 pmol/L with a normal thyroid-stimulating hormone (TSH) level. Patients whose TSH levels were abnormally high or abnormally low were excluded from this study. The primary endpoint was the occurrence of sudden cardiac death (SCD) events, and the secondary endpoint was a composite of worsening heart failure (WHF) events, including heart failure death, cardiac decompensation, hospitalization for heart failure, and HCM-related stroke. The Kaplan-Meier and Cox regression were performed for the survival analysis. RESULTS: After a median follow-up of 52 months, 75 SCD events and 134 WHF events were recorded. The Kaplan-Meier survival curves showed that the cumulative incidence of SCD events and WHF events were significantly higher in patients with low T3 syndrome (log-rank p = .02 and log-rank p = .001, respectively). Furthermore, multivariate Cox regression analysis demonstrated that low T3 syndrome is a strong predictor of SCD events and WHF events (adjusted hazard ratio [HR: 1.53, 95% confidence interval [CI]: 1.13-2.24, p < .01; HR: 3.87, 95% CI: 2.91-4.98, p < .001, respectively). CONCLUSIONS: Low T3 syndrome is highly prevalent among patients with HCM and was independently associated with an increased risk of SCD events and WHF events. The routine assessment of serum fT3 levels may provide risk stratification in this population.


Asunto(s)
Cardiomiopatía Hipertrófica , Síndromes del Eutiroideo Enfermo , Cardiopatías , Insuficiencia Cardíaca , Humanos , Síndromes del Eutiroideo Enfermo/complicaciones , Triyodotironina , Factores de Riesgo , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/diagnóstico , Cardiopatías/complicaciones , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología , Insuficiencia Cardíaca/complicaciones , Tirotropina , Pronóstico
16.
Zhongguo Zhong Yao Za Zhi ; 37(3): 344-7, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22568237

RESUMEN

OBJECTIVE: To detect the effect and mechanism of procyanidin foom vaccinium (PC) on myocardial fibrosis in rats. METHOD: The myocardial fibrosis model in rats was built by subcutaneous injection of 5 mg x kg(-1) x d(-1) of isoprenaline (Iso) for 7 days in vivo while intragastrically administrating PC 100, 200 and 400 mg x kg(-1) x d(-1) for 14 days. Following the model was established, myocardial indexes (heart weight/body weight, HW/BW and left ventricalar weight/body weight, LVW/BW) were measured. Besides, angiotensin II and I , III collagen quantification levels in blood serum were determined respectively by ELISA. The change in the content of nitric oxide (NO) in blood serum was determined with colorimetry. The content of malondialdehyde (MDA) in left ventricle was assayed with spectrophotometry. The contents of lactate dehydrogenase (LDH) and creatine kinase (CK) in blood serum were detected with automatic biochemistry analyzer. RESULT: Compared with the control group, the myocardial indexes, the contents of I , III collagen quantification, angiotensin II in blood serum and malondialdehyde in left ventricle were markedly increased and the content of nitric oxide in blood serum was decreased, the contents of lactate dehydrogenase and creatine kinase in blood serum were markedly increased in Iso model group (P<0.05 or P<0.01). Compared with the model group, the myocardial indexes were decreased, the contents of I , III collagen quantification, angiotensin II in blood serum were reduced in PC 200 and 400 mg x kg(-1) x d(-1) groups (P<0.05 or P<0.01). The content of nitric oxide in blood serum was increased, the content of malondialdehyde in left ventricle was markedly decreased, the contents of lactate dehydrogenase and creatine kinase in blood serum were markedly decreased in PC three groups (P<0.05 or P<0.01). CONCLUSION: PC could inhibit collagen synthesis by decreasing angiotensin II level and increasing the content of nitric oxide and antioxidation, and thereby inhibiting myocardial fibrosis and protect myocardium in rats.


Asunto(s)
Antioxidantes/farmacología , Biflavonoides/farmacología , Catequina/farmacología , Fibrosis Endomiocárdica/tratamiento farmacológico , Fibrosis Endomiocárdica/metabolismo , Isoproterenol/efectos adversos , Proantocianidinas/farmacología , Vaccinium/química , Angiotensinas/sangre , Animales , Antioxidantes/administración & dosificación , Biflavonoides/administración & dosificación , Catequina/administración & dosificación , Fibrosis Endomiocárdica/inducido químicamente , Femenino , Masculino , Malondialdehído/metabolismo , Óxido Nítrico/sangre , Proantocianidinas/administración & dosificación , Ratas , Ratas Wistar , Remodelación Ventricular/efectos de los fármacos
17.
Front Cardiovasc Med ; 9: 934279, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36082113

RESUMEN

Non-obstructive coronary artery disease (CAD), which is defined as coronary stenosis <50%, has been increasingly recognized as an emerging entity in clinical practice. Vasomotion abnormality and coronary microvascular dysfunction are two major mechanisms contributing to the occur of angina with non-obstructive CAD. Although routine coronary functional assessment is limited due to several disadvantages, functional evaluation can help to understand the pathophysiological mechanism and/or to exclude specific etiologies. In this review, we summarized the potential mechanisms involved in ischemia with non-obstructive coronary arteries (INOCA) and myocardial infarction with non-obstructive coronary arteries (MINOCA), the two major form of non-obstructive CAD. Additionally, we reviewed currently available functional assessment indices and their use in non-obstructive CAD. Furthermore, we speculated that novel technique combined anatomic and physiologic parameters might provide more individualized therapeutic choice for patients with non-obstructive CAD.

18.
Front Microbiol ; 13: 868312, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35633708

RESUMEN

Intercropping is widely used in agricultural production due to its capability of raising land productivity and providing an opportunity to achieve sustainable intensification of agriculture. In this study, soil samples from 10 to 20 cm depth of intercropping Pinto peanut in litchi orchard and litchi monoculture mode were established to determine soil attributes, enzyme activities, as well as the effect on soil bacterial diversity. On this basis, 16S rRNA V4-V5 region of soil bacterial communities in litchi/Pinto peanut intercropping (LP) mode and litchi monoculture mode (CK) was detected by the Illumina MiSeq sequencing platform. The results showed that the content of available potassium (AK) in LP was significantly higher than that in CK by 138.9%, and the content of available nitrogen (AN) in LP was significantly lower than that in CK by 19.6%. The soil enzyme activities were higher in LP as a whole, especially sucrase (SC) and acid protease (PT) were significantly higher by 154.4 and 76.5%, respectively. The absolute abundance and alpha diversity of soil microbiota were significantly higher in the intercropping group. Most importantly, endemic species with a significant difference in LP was higher by ~60 times compared to CK treatment. In the aspect of soil bacterial community structure, the dominant phyla of the two groups were Acidobacteria, Proteobacteria, Chloroflexi, and Actinobacteria. At the genus level, the absolute abundance of Flavobacterium and Nitrososphaera was significantly higher by 79.20 and 72.93%, respectively, while that of Candidatus_Koribacter was significantly lower with an amplitude of 62.24% in LP than in CK. Furthermore, the redundancy analysis (RDA) suggested that AK, which was highly associated with the dominant genera and phyla, is the vitally dominating environmental factors in LP groups, while in CK groups, it is AN and pH. In addition, PICRUSt2 analysis indicated that intercropping improved the metabolic activity of bacteria which can be correlated to the resistance of litchi root systems to soil-borne diseases. Overall, this study is expected to provide a theoretical basis and technical support for the healthy intercropping cultivation of litchi.

19.
Integr Cancer Ther ; 21: 15347354221086900, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35297710

RESUMEN

Triple-negative breast cancer is an aggressive subtype of breast cancer with poor clinical outcomes and poor prognosis. Hesperetin is an active component extracted from Citrus fruits and Traditional Chinese Medicine has a wide range of pharmacological effects. Here, we assessed the anti-migration and anti-invasive effects and explored inhibitory mechanisms of hesperetin on metastasis of human triple negative breast cancer MDA-MB-231 cells. Cell viability experiments revealed that 200 µM hesperetin has a clear inhibitory effect on MDA-MB-231 cells. TGF-ß1 treatment induces apparent tumor progression in MDA-MB-231 cells including aberrant wound-healing and invasion ability, which is effectively suppressed by hesperetin co-treatment. Additionally, hesperetin inhibited the TGF-ß1-mediated actin stress fiber formation. Western blot results showed that hesperetin suppressed the TGF-ß1-mediated (i) activation of Fyn, (ii) phosphorylation of paxillin at Y31, Y88, and Y118 sites, (iii) the increased expression of RhoA, and (iv) activation of Rho-kinase. We demonstrated the increased interaction of Fyn with paxillin and RhoA protein in the TGF-ß1-induced metastasis of MDA-MB-231 cells. Small interfering RNA Fyn inhibited phosphorylation of paxillin (Y31) and activation of Rho-kinase induced by TGF-ß1. In conclusion, hesperetin has a significant inhibitory effect on migration and invasion of MDA-MB-231 cells induced by TGF-ß1, which might be attributed to inhibiting the Fyn/paxillin/RhoA pathway.


Asunto(s)
Hesperidina , Paxillin , Proteínas Proto-Oncogénicas c-fyn , Neoplasias de la Mama Triple Negativas , Proteína de Unión al GTP rhoA , Línea Celular Tumoral , Movimiento Celular , Femenino , Hesperidina/farmacología , Humanos , Paxillin/metabolismo , Proteínas Proto-Oncogénicas c-fyn/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Proteína de Unión al GTP rhoA/metabolismo
20.
Front Cardiovasc Med ; 9: 890506, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35665258

RESUMEN

Background: Hypertrophic cardiomyopathy (HCM) is the prevalent inherited cardiomyopathy and a major contributor to sudden death and heart failure in young adults. Although depression has been associated with poor prognosis in patients with cardiovascular disease, the relationship between anxiety and HCM clinical outcomes has not been addressed. We aimed to determine the prevalence of anxiety symptoms in patients with HCM and the association between anxiety and adverse prognosis in this population. Methods: A total of 793 patients with HCM were prospectively enrolled and followed up for a mean of 4.1 years from March 2014 to January 2018. The primary endpoint was sudden cardiac death (SCD) events, and the secondary endpoint was HCM-related heart failure events. Anxiety symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS) during outpatient visits or hospital stays. Results: Elevated scores on the HADS anxiety subscale (HADS-A ≥ 8) were defined as clinically significant anxiety. SCD and HCM-related heart failure events occurred in 76 and 149 patients, respectively, during the follow-up period. Kaplan-Meier survival curves demonstrated the significant association of anxiety with SCD events (log-rank P = 0.012) and HCM-related heart failure events (log-rank P = 0.001). Multivariable Cox regression analysis showed anxiety as a predictor of SCD events and HCM-related heart failure events (adjusted hazard ratio [HR] = 1.42, 95% confidence interval [CI] = 1.12-2.04, P = 0.03; adjusted HR = 2.9,2 95% CI = 1.73-4.03, P < 0.001), independent of conventional risk factors and depression. Besides, patients with comorbid anxiety and depression showed a fourfold higher risk of heart failure events and 3.5-fold higher risk of SCD versus those with neither (adjusted HR = 4.08, 95% CI = 2.76-5.91, P < 0.001; adjusted HR = 3.52, 95% CI = 2.24-4.67, P < 0.001, respectively). Conclusions: Anxiety was prevalent among Chinese patients with HCM, and it was independently associated with a higher risk of SCD and HCM-related heart failure events, particularly when comorbid with depression. Psychological assessment and intervention should be considered to alleviate anxiety symptoms in this population. Clinical Trial Registration: http://www.chictr.org.cn, identifier: ChiCTR2000040759.

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