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1.
Proc Natl Acad Sci U S A ; 116(44): 22347-22352, 2019 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-31611410

RESUMEN

Observing the structure and regeneration of the myelin sheath in peripheral nerves following injury and during repair would help in understanding the pathogenesis and treatment of neurological diseases caused by an abnormal myelin sheath. In the present study, transmission electron microscopy, immunofluorescence staining, and transcriptome analyses were used to investigate the structure and regeneration of the myelin sheath after end-to-end anastomosis, autologous nerve transplantation, and nerve tube transplantation in a rat model of sciatic nerve injury, with normal optic nerve, oculomotor nerve, sciatic nerve, and Schwann cells used as controls. The results suggested that the double-bilayer was the structural unit that constituted the myelin sheath. The major feature during regeneration was the compaction of the myelin sheath, wherein the distance between the 2 layers of cell membrane in the double-bilayer became shorter and the adjacent double-bilayers tightly closed together and formed the major dense line. The expression level of myelin basic protein was positively correlated with the formation of the major dense line, and the compacted myelin sheath could not be formed without the anchoring of the lipophilin particles to the myelin sheath.


Asunto(s)
Vaina de Mielina/ultraestructura , Regeneración Nerviosa , Traumatismos de los Nervios Periféricos/metabolismo , Animales , Axones/metabolismo , Axones/ultraestructura , Vaina de Mielina/metabolismo , Traumatismos de los Nervios Periféricos/patología , Ratas
2.
Analyst ; 145(16): 5547-5552, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32609115

RESUMEN

MicroRNAs (miRNAs) play a vital role in various biological processes and act as important biomarkers for clinical cancer diagnosis, prognosis, and therapy. Here, we took advantage of Cas12a trans-cleavage activity to develop an enzyme-assisted cascade amplification method for isothermal miRNA detection. A target miRNA-initiated ligation reaction would allow for the production of transcription templates that triggered the transcriptional amplification of RNA strands. These RNA strands were cleaved by the 8-17E DNAzyme to generate crRNAs and recycled RNAs which have the same sequence as the target miRNA. The amplified abundant crRNAs bound to Cas12a and dsDNA activators to form the complex, which trans-cleaved the ssDNA reporters to generate a fluorescence signal for miRNA quantitative analysis. The proposed method exhibits a femtomolar limit of detection and a good specificity in distinguishing the homologous sequences of miRNAs. Its practical application ability was further tested in different cell lines.


Asunto(s)
ADN Catalítico , MicroARNs , Sistemas CRISPR-Cas , ADN , MicroARNs/genética , Técnicas de Amplificación de Ácido Nucleico
3.
Asian-Australas J Anim Sci ; 33(11): 1763-1769, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32054191

RESUMEN

OBJECTIVE: This study was conducted to investigate the effect of L-carnitine on the pig semen characteristics during storage. METHODS: Spermatozoa samples were examined for spermatozoa quality and then randomly divided into 5 groups: 0 (control), 12.5, 25, 50, and 100 mM L-carnitine. Sperm motility, plasma membrane integrity and antioxidant parameters (total reactive oxygen species, total antioxidant capacity, and malondialdehyde) were evaluated after 0, 3, 5, and 10 day cooledstorage at 17°C. Moreover, ATP content, mitochondria activity as well as sperm-binding and in vitro fertilizing ability of preserved boar sperm were also investigated. RESULTS: Supplementation with 50 mM L-carnitine could effectively maintain boar sperm quality parameters such as sperm motility and membrane integrity. Besides, we found that L-carnitine had positive effects on boar sperm quality mainly through improving antioxidant capacities and enhancing ATP content and mitochondria activity. Interestingly, by assessing the effect of L-carnitine on sperm fertility and developmental potential, we discovered that the extender containing L-carnitine could improve sperm quality and increase the number of sperms bounding to zona pellucida, without improving in vitro fertility and development potential. CONCLUSION: These findings suggested that the proper addition of L-carnitine to the semen extender improved boar sperm quality during liquid storage at 17°C.

4.
Reprod Domest Anim ; 54(8): 1069-1077, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31099063

RESUMEN

Spermatozoa are highly specialized cells, and energy metabolism plays an important role in modulating sperm viability and function. Rosiglitazone is an antidiabetic drug in the thiazolidinedione class that regulates metabolic flexibility and glucose uptake in various cell types, but its effects on boar sperm metabolism are unknown. In this study, we investigated the potential effect of rosiglitazone against time-dependent deterioration of boar spermatozoa during liquid preservation at 17°C. Freshly ejaculated semen was diluted with Beltsville Thawing Solution (BTS) containing different concentrations of rosiglitazone, and the motility, membrane and acrosome integrity of sperm were detected. Besides, we measured glucose uptake capacity, l-lactate production level, mitochondrial membrane potential, adenosine triphosphate (ATP) content and mitochondrial reactive oxygen species (mROS) production of sperm after boar semen had been incubated with or without rosiglitazone, iodoacetate (glycolysis inhibitor) and rotenone (electron transport chain inhibitor) for 5 days. The addition of rosiglitazone significantly enhanced sperm quality and had a strong protective effect on the sperm membrane and acrosome integrity during storage. BTS containing 50 µM rosiglitazone maintained the total motility of liquid-preserved sperm above 60% for 7 days. Rosiglitazone improved sperm quality by regulating energy metabolism manner of preserved sperm, protected the sperm mitochondrial membrane potential, enhanced sperm ATP production and in the meanwhile reduced mROS through enhancing glycolysis but not oxidative phosphorylation. The data suggested the practical feasibility of using rosiglitazone for improving boar spermatozoa quality during semen preservation.


Asunto(s)
Hipoglucemiantes/farmacología , Rosiglitazona/farmacología , Preservación de Semen/veterinaria , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiología , Porcinos , Animales , Crioprotectores/farmacología , Metabolismo Energético , Masculino , Motilidad Espermática
5.
Angew Chem Int Ed Engl ; 58(16): 5382-5386, 2019 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-30773764

RESUMEN

We have developed an ingenious method, termed Cas9 nickase-based amplification reaction (Cas9nAR), to amplify a target fragment from genomic DNA at a constant temperature of 37 °C. Cas9nAR employs a sgRNA:Cas9n complex with a single-strand nicking property, a strand-displacing DNA polymerase, and two primers bearing the cleavage sequence of Cas9n, to promote cycles of DNA replication through priming, extension, nicking, and displacement reaction steps. Cas9nAR exhibits a zeptomolar limit of detection (2 copies in 20 µL of reaction system) within 60 min and a single-base discrimination capability. More importantly, the underlying principle of Cas9nAR offers simplicity in primer design and universality in application. Considering the superior sensitivity and specificity, as well as the simple-to-implement, rapid, and isothermal features, Cas9nAR holds great potential to become a routine assay for the quantitative detection of nucleic acids in basic and applied studies.


Asunto(s)
Proteína 9 Asociada a CRISPR/metabolismo , ADN Bacteriano/genética , Técnicas de Amplificación de Ácido Nucleico , ARN Guía de Kinetoplastida/metabolismo , Temperatura , Sistemas CRISPR-Cas , Replicación del ADN , Salmonella typhimurium/genética
6.
Fungal Genet Biol ; 113: 24-31, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29410210

RESUMEN

Pbs2, Mkk1 and Ste7 orthologs are three mitogen-activated protein kinase (MAPK) kinases (MAPKKs) acting as checkpoints of the Hog1, Slt2 and Fus3 MAPK cascades that constitute major parts of fungal signaling network. Here, we show that three other MAPKK-like proteins (Mkk4/5/6) exist in Beauveria bassiana and other entomopathogenic or non-entomopathogenic fungi but lack in yeasts and aspergilli, and elucidate how they function in the fungal insect pathogen. Based on phenotypic defects of single-, double- and triple-deletion mutants, Mkk4, Mkk5 and Mkk6 played collaborative or independent roles in sustaining radial growth on various media, conidiation capacity, conidial germination, conidial UV-B resistance, and/or virulence. In stress assays, three single-deletion Δmkk mutants showed increased tolerance to cell wall stress but null response to a 3-h heat shock at 40 °C during normal incubation. Only did Δmkk6 exhibit increased sensitivity to either menadione or H2O2 oxidation. Intriguingly, Δmkk5 and Δmkk6 displayed a remarkable increase in cellular sensitivity to a high osmolarity of NaCl or KCl instead of non-salt sorbitol, suggesting a link of their increased sensitivity to the toxicity of a high Na+/K+ concentration rather than to the plausible osmotic stress of either salt. However, all of the deletion mutants showed no resistance to fludioxonil, a phenylpyrrole-type fungicide. A discussion is provided on whether Mkk4, Mkk5 and Mkk6 could be likely associated with or without the MAPK cascades in B. bassiana.


Asunto(s)
Beauveria/enzimología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Animales , Antifúngicos/farmacología , Beauveria/genética , Pared Celular/genética , Pared Celular/metabolismo , Eliminación de Gen , Respuesta al Choque Térmico , Peróxido de Hidrógeno/metabolismo , Insectos/microbiología , Presión Osmótica , Cloruro de Potasio/farmacología , Transducción de Señal , Cloruro de Sodio/farmacología , Sorbitol/farmacología , Esporas Fúngicas/crecimiento & desarrollo , Estrés Fisiológico , Virulencia , Vitamina K 3/metabolismo
7.
Biol Reprod ; 98(2): 218-226, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29267849

RESUMEN

Mechanisms for postovulatory aging (POA) of oocytes and for spontaneous activation (SA) of rat oocytes are largely unknown. Expression of calcium-sensing receptor (CaSR) in rat oocytes and its role in POA remain unexplored. In this study, expression of CaSR in rat oocytes aging for different times was detected by immunofluorescence microscopy, and western blotting and the role of CaSR in POA was determined by observing the effects of regulating its activity on SA susceptibility and cytoplasmic calcium levels. The results showed that CaSR was expressed in rat oocytes. Oocytes recovered 19 h post human chorionic gonadotropin (hCG) injection were more susceptible to SA and expressed more functional CaSR than oocytes recovered 13 h after hCG injection, although both expressed the same level of total CaSR protein. Treatment with CaSR antagonist significantly suppressed cytoplasmic calcium elevation and SA of oocytes. Activation of Na-Ca2+ exchanger with NaCl inhibited SA to a greater extent than suppression of CaSR with NPS-2143, suggesting that calcium sources other than CaSR-controlled channels contributed to the elevation of cytoplasmic calcium. Treatment with T- or L-type calcium channel blockers significantly reduced SA. Suppression of all calcium channels tested reduced SA to minimum. It is concluded that the level of CaSR functional dimer protein, but not that of the total CaSR protein, was positively correlated with the SA susceptibility during POA of rat oocytes confirming that CaSR is involved in POA regulation. Blocking multiple calcium channels might be a better choice for efficient control of SA in rat oocytes.


Asunto(s)
Oocitos/metabolismo , Ovulación/metabolismo , Receptores Sensibles al Calcio/metabolismo , Animales , Gonadotropina Coriónica/farmacología , Femenino , Naftalenos/farmacología , Oocitos/efectos de los fármacos , Ovulación/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores Sensibles al Calcio/antagonistas & inhibidores , Intercambiador de Sodio-Calcio/metabolismo
8.
Environ Microbiol ; 19(5): 1808-1821, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28076898

RESUMEN

High-osmolarity glycerol (HOG) pathway required for yeast osmoregulation relies upon the mitogen-activated protein kinase (MAPK) Hog1 cascade that comprise the MAPKKKs Ssk2/Ssk22 and Ste11 converging on the MAPKK Pbs2. Here we show a Hog1 cascade with the unique MAPKKK Ssk2 acting in Beauveria bassiana. Hypersensitivity to high osmolarity and high resistance to fludioxonil fungicide appeared in Δssk2, Δpbs2 and Δhog1 mutants whereas the two hallmark phenotypes were reversed in Δste11. Increased sensitivity to heat shock and decreased sensitivity to cell wall perturbation also occurred in the three mutants but not in Δste11 although antioxidant phenotypes were different in all deletion mutants. Intriguingly, signals of Hog1 phosphorylation induced by osmotic, oxidative and thermal cues were present in Δste11 but absent in Δssk2 and Δpbs2. Moreover, vegetative growth on minimal media with different carbon/nitrogen sources was much more suppressed in Δste11 and Δssk2 than in Δpbs2 and Δhog1 although all mutants suffered similar, but severe, conidiation defects on a standard medium. Normal host infection was abolished in Δste11 while virulence was differentially attenuated in other mutants. Our findings exclude Ste11 from the Hog1 cascade that regulates multiple stress responses and environmental adaptation of B. bassiana and perhaps other filamentous fungi.


Asunto(s)
Beauveria/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Osmorregulación/fisiología , Presión Osmótica/fisiología , Beauveria/patogenicidad , Pared Celular/metabolismo , Proteínas Fúngicas/genética , Eliminación de Gen , Glicerol/metabolismo , Quinasas Quinasa Quinasa PAM/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Osmorregulación/genética , Fenotipo , Fosforilación , Virulencia
9.
Environ Microbiol ; 19(7): 2806-2818, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28557308

RESUMEN

High proportions of hypothetical proteins exist in genomic databases of fungi, including putative secretory proteins (PSPs) likely involved in fungal invasion and virulence. Here we characterize one of many PSPs revealed in the previous transcriptome of Beauveria bassiana (a fungal insect pathogen) infecting a global lepidopteran pest and name it vacuole-localized protein 4 (VLP4) because this small, domain-lacking protein (22.96 kDa) was specifically localized in the vacuoles of hyphal cells. Deletion of VLP4 resulted in repression of almost all genes acting in autophagy and central development pathways. Consequently, the deletion mutant formed no autophagosome in hyphal vacuoles and displayed severe defects in aerial conidiation. conidial hydrophobicity to the insect surface, and secretion of cuticle-degrading Pr1 proteases required for normal cuticle infection. Blastospore formation was inhibited in the submerged mutant culture mimic to insect haemolymph, and formation of hyphal bodies in vivo was delayed. The fungal virulence was attenuated in the absence of VLP4. These phenotypic defects were well restored by targeted gene complementation. Our findings unveil a vital role of VLP4 in B. bassiana and call attention to many more PSPs for new insights into the interactions of fungal insect pathogens with insects.


Asunto(s)
Autofagia/fisiología , Beauveria/genética , Beauveria/patogenicidad , Proteínas Fúngicas/genética , Factores de Virulencia/genética , Animales , Autofagia/genética , Hifa/metabolismo , Insectos/microbiología , Esporas Fúngicas/metabolismo , Virulencia/genética
10.
Fungal Genet Biol ; 105: 8-15, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28552321

RESUMEN

Cyclophilin B (CypB) was previously revealed as one of many putative secretory proteins in the transcriptome of Beauveria bassiana infection to a lepidopteran pest. Here we show a main localization of CypB in hyphal cell walls and septa and its essential role in the in vitro and in vivo asexual cycles of the fungal insect pathogen. Deletion of cypB reduced colony growth by 16-42% on two rich media and 30 scant media with different carbon or nitrogen sources. The deletion mutant suffered a delayed conidiation on a standard medium and a final 47% reduction in conidial yield, accompanied with drastic transcript depression of several key genes required for conidiation and conidial maturation. The mutant conidia required 10h longer to germinate 50% at optimal 25°C than wild-type conidia. Intriguingly, cultivation of the mutant conidia in a trehalose-peptone broth mimic to insect hemolymph resulted in 83% reduction in blastospore yield but only slight decrease in biomass level, indicating severe defects in transition of hyphae to blastospores. LT50 for the deletion mutant against Galleria mellonella larvae through normal cuticle infection was prolonged to 7.4d from a wild-type estimate of 4.7d. During colony growth, additionally, the deletion mutant displayed hypersensitivity to Congo red, menadione, H2O2 and heat shock but increased tolerance to cyclosporine A and rapamycin. All of changes were restored by targeted gene complementation. Altogether, CypB takes part in sustaining normal growth, aerial conidiation, conidial germination, dimorphic transition, stress tolerance and pathogenicity in B. bassiana.


Asunto(s)
Beauveria/crecimiento & desarrollo , Ciclofilinas/fisiología , Beauveria/genética , Beauveria/patogenicidad , Ciclofilinas/genética , Ciclofilinas/aislamiento & purificación , Mutagénesis , Reproducción Asexuada , Estrés Fisiológico , Virulencia
11.
Appl Microbiol Biotechnol ; 101(18): 6941-6949, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28766034

RESUMEN

The mitogen-activated protein kinase (MAPK) Mpk3/MpkC resembles the MAPK Hog1 but does not necessarily function in some filamentous fungi. Here, we compared functions of Mpk3 and Hog1 in Beauveria bassiana, a filamentous fungal insect pathogen, by multi-phenotypic analyses of their single/double deletion mutants. Growth defects of Δmpk3 were moderate on all 14 minimal media with different carbon or nitrogen sources and less severe than those of Δhog1 on most media tested. The double deletion mutant suffered significantly more severe growth defects than those observed in Δmpk3 and Δhog1, suggesting overlapping and collaborative roles of Mpk3 and Hog1 in uptake of six carbon and four nitrogen sources during normal growth. Despite little impact on conidiation capacity, mpk3 deletion slowed down conidial germination as much as hog1 or double deletion. Conidial resistance to UV-B irradiation decreased less in Δmpk3 than in Δhog1 or in the double mutant. The fungal virulence was similarly attenuated for all deletion mutants against Galleria mellonella larvae through normal cuticle infection. Intriguingly, the Δmpk3 mutant displayed null response to high osmolarity and fludioxonil fungicide, to which both Δhog1 and double mutants were hypersensitive and highly resistant, respectively, but it was more sensitive to a 3-h heat shock at 40 °C than Δhog1 during normal incubation. Western blot hybridization demonstrated that Mpk3 could collaborate with Hog1 in response to heat shock rather than to the chemical stresses. Altogether, Mpk3 collaborates with Hog1 only in response to heat shock and functions in sustaining the pest control potential of B. bassiana.


Asunto(s)
Beauveria/fisiología , Lepidópteros/microbiología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Animales , Beauveria/genética , Beauveria/patogenicidad , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Respuesta al Choque Térmico , Larva , Proteínas Quinasas Activadas por Mitógenos/genética , Fenotipo , Esporas Fúngicas , Estrés Fisiológico , Virulencia
12.
J Cardiovasc Electrophysiol ; 27(12): 1472-1482, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27558843

RESUMEN

BACKGROUND: The human ether-a-go-go-related gene (hERG) is the major molecular component of the rapidly activating delayed rectifier K+ current (Ikr ). Impairment of hERG function is believed to be a mechanism causing long-QT syndromes (LQTS). Growing evidences have shown that microRNAs (miRNAs) are involved in functional modulation of the hERG pathway. The purpose of this study was to screen and validate miRNAs that regulate the hERG pathway. The miRNAs identified in this study will provide new tools to assess the mechanism of LQTS. METHODS: Six miRNAs were selected by algorithm predictions based on potential interaction with hERG. The effects of each miRNA on hERG were assessed by use of the Dual-Luciferase Reporter assay system, qRT-PCR, Western blotting, and confocal fluorescence microscopy. Furthermore, whole-cell patch clamp technique was used to validate the effect of miR-103a-1 on the electrophysiological characteristic of the Ikr of the hERG protein channel. RESULTS: miR-134, miR-103a-1, miR-143, and miR-3619 significantly downregulated luciferase activity (P < 0.05) in a reporter test system. These 4 miRNAs significantly suppressed expression of hERG mRNA and protein in U2OS cells (P < 0.05).Corresponding AMOs rescued expression of hERG mRNA and protein. Confocal microscopy showed that all 4 miRNAs reduced the expression of both immature and mature hERG protein. miR-103a-1 decreased the maximum current and tail current amplitudes of hERG channel. CONCLUSIONS: Expression and functions of hERG are regulated by specific miRNAs.


Asunto(s)
Canal de Potasio ERG1/metabolismo , Activación del Canal Iónico , Síndrome de QT Prolongado/metabolismo , MicroARNs/metabolismo , Línea Celular Tumoral , Biología Computacional , Bases de Datos Genéticas , Regulación hacia Abajo , Canal de Potasio ERG1/genética , Células HEK293 , Humanos , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/fisiopatología , Potenciales de la Membrana , MicroARNs/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transfección
13.
BMJ ; 384: e078581, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443074

RESUMEN

OBJECTIVE: To evaluate the diagnostic accuracy and safety of using magnetically guided capsule endoscopy with a detachable string (ds-MCE) for detecting and grading oesophagogastric varices in adults with cirrhosis. DESIGN: Prospective multicentre diagnostic accuracy study. SETTING: 14 medical centres in China. PARTICIPANTS: 607 adults (>18 years) with cirrhosis recruited between 7 January 2021 and 25 August 2022. Participants underwent ds-MCE (index test), followed by oesophagogastroduodenoscopy (OGD, reference test) within 48 hours. The participants were divided into development and validation cohorts in a ratio of 2:1. MAIN OUTCOME MEASURES: The primary outcomes were the sensitivity and specificity of ds-MCE in detecting oesophagogastric varices compared with OGD. Secondary outcomes included the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices and the diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices. RESULTS: ds-MCE and OGD examinations were completed in 582 (95.9%) of the 607 participants. Using OGD as the reference standard, ds-MCE had a sensitivity of 97.5% (95% confidence interval 95.5% to 98.7%) and specificity of 97.8% (94.4% to 99.1%) for detecting oesophagogastric varices (both P<0.001 compared with a prespecified 85% threshold). When using the optimal 18% threshold for luminal circumference of the oesophagus derived from the development cohort (n=393), the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices in the validation cohort (n=189) were 95.8% (89.7% to 98.4%) and 94.7% (88.2% to 97.7%), respectively. The diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices was 96.3% (92.6% to 98.2%), 96.9% (95.2% to 98.0%), and 96.7% (95.0% to 97.9%), respectively. Two serious adverse events occurred with OGD but none with ds-MCE. CONCLUSION: The findings of this study suggest that ds-MCE is a highly accurate and safe diagnostic tool for detecting and grading oesophagogastric varices and is a promising alternative to OGD for screening and surveillance of oesophagogastric varices in patients with cirrhosis. TRIAL REGISTRATION: ClinicalTrials.gov NCT03748563.


Asunto(s)
Endoscopía Capsular , Várices Esofágicas y Gástricas , Várices , Adulto , Humanos , Várices Esofágicas y Gástricas/diagnóstico , Várices Esofágicas y Gástricas/etiología , Cirrosis Hepática/complicaciones , Estudios Prospectivos
14.
Int J Nanomedicine ; 18: 1145-1158, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36915699

RESUMEN

Background: Drug-resistant microbes pose a global health concern, requiring the urgent development of effective antibacterial agents and strategies in clinical practice. Therefore, there is an urgent need to explore novel antibacterial materials to effectively eliminate bacteria. The synthesis of quaternary phosphonium salt in haloargentate systems, wherein the phosphorus atom is represented in a cationic form, is a possible strategy for the development of antibacterial materials. Methods: Using (triphenyl)phosphonium-based quaternary phosphorus salts with different spacer lengths (n=2, 4, 6) as a template, we designed three kinds of quaternary phosphorus salts as effective antibacterial agents against drug-resistant bacteria. Results: The synthesized quaternary phosphorus salt of (1,4-DBTPP)Br2 effectively prevented the formation of the bacterial biofilms, and degraded bacterial membranes and cell walls by promoting the production of reactive oxygen species, which exhibited effective therapeutic effects in a rat model of a superficial wound infected with methicillin-resistant Staphylococcus aureus. Conclusion: The quaternary phosphorus salt (1,4-DBTPP)Br2 demonstrated hemocompatibility and low toxicity, revealing its potential in the treatment of clinical infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Ratas , Animales , Fósforo , Sales (Química)/farmacología , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Cloruro de Sodio/farmacología , Cicatrización de Heridas
15.
Yi Chuan ; 34(5): 609-14, 2012 May.
Artículo en Zh | MEDLINE | ID: mdl-22659433

RESUMEN

The cDNA Djtry, encoding a planarian trypsin, was identified from the cDNA library of Dugesia japonica. Multiple alignment analysis showed that the Tryps_SPc domain contained the incompletely conserved catalytic triad in which the first amino acid His was substituted by Lys. Phylogenetic analysis indicateed that Djtry protein falls at the base of other animal trypsins. The Djtry cDNA was cloned into a bacterial vector pET-28a and was transferred into E. coli BL21. The His-tagged Djtry fusion protein expression was induced by IPTG. SDS-PAGE analysis revealed that the Djtry was expressed as inclusion bodies in E. coli BL21 with the estimated molecular weight of approximately 26 kDa. Western blotting with His-tag antibody showed that the antibody was reacted with the fusion protein after refolding. Compared to bovine trypsin using BAEE as special substrate of trypsin, the enzyme activity of Djtry was measured. These results indicate that Djtry represents the archetype of animal trypsins, and this type of mutational trypsin Djtry still performs the trypsin nature with slightly weaker activity.


Asunto(s)
Planarias/enzimología , Tripsina/genética , Tripsina/metabolismo , Secuencia de Aminoácidos , Animales , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/aislamiento & purificación , Tripsina/química
16.
Surg Oncol ; 38: 101628, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34174770

RESUMEN

BACKGROUND AND OBJECTIVES: Lymph node metastasis is crucial for gastric cancer. We aim to explore the value of preoperative gastroscopic carbon nanoparticles labeling in patients undergoing laparoscopic radical gastric cancer surgery. METHODS: 1199 cases undergoing laparoscopic radical gastric cancer surgery were retrospectively analyzed. 214 cases received preoperative gastroscopic carbon nanoparticles labeling. The number of total lymph nodes detected, positive lymph nodes, N staging, and operation time were analyzed. RESULTS: The patients received carbon nanoparticles labeling had more total lymph nodes detected (27.9 ± 6.5 vs 22.2 ± 4.0; P < 0.001) and shorter operation time (185.9 ± 27.8min vs 218.7 ± 69.2min; P < 0.001) compared with the control group. In addition, preoperative endoscopic carbon nanoparticles labeling improved the diagnosis rate of synchronous multiple gastric cancer (2.8% vs 0.4%; P < 0.001). CONCLUSIONS: Preoperative endoscopic carbon nanoparticles tracer labeling is of great value in patients undergoing laparoscopic radical gastric cancer surgery. It shortens the operation time, increases the number of total lymph nodes detected for more accurate pathological TNM staging, and finds some cases of synchronous multiple gastric cancer.


Asunto(s)
Carbono/análisis , Gastroscopía/métodos , Laparoscopía/métodos , Ganglios Linfáticos/patología , Nanopartículas/administración & dosificación , Cuidados Preoperatorios , Neoplasias Gástricas/patología , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Masculino , Persona de Mediana Edad , Nanopartículas/química , Tempo Operativo , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/cirugía
17.
Mol Immunol ; 123: 106-115, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32485469

RESUMEN

Hepatocytes are the targets in autoimmune hepatitis (AIH) that results in T cell-dependent liver injury. However, hepatocytes may also affect the hepatic T cells in AIH, but the underlying mechanisms are not fully understood. Here we report that hepatocytes could secrete galectin-9 (Gal-9) to suppress the intrahepatic production of Th1 cytokine IFN-γ and restrict AIH development, but hepatocyte damage resulted in opposite effects due to release of TLR2/4 ligands that promoted the intrahepatic production of IL-1ß, IL-6, and IL-12. Through Tim-3, Gal-9 could efficiently suppress the intrahepatic T cell activation despite presence of TLR2/4 ligands, thus attenuating Th1 response in AIH. Intriguingly, intrahepatic IL-6/IL-12 suppressed the effect of TGF-ß on Treg cells. Therefore, in AIH, Gal-9 promoted Foxp3 expression and function of hepatic Treg cells through TL1A signaling, although Treg function was still impaired, compared with that in naive state. Due to its promoting effect on Treg function, together with its effect on T effector cells in a Tim-3-independent way, Gal-9 could attenuate intrahepatic IFN-γ production by hindering the increase of hepatic CD4+CD43+ T cells resulting from extrahepatic T cell activation. TLR2/4 ligands attenuated the effects of Gal-9 on Treg cells and CD4+CD43+ T cells by increasing intrahepatic IL-6 and IL-12. Blocking TLR2/4 ligands could efficiently suppress intrahepatic IFN-γ production, liver injury, and hepatic fibrosis. These findings suggest that hepatocytes paradoxically affect Th1 response in AIH due to Gal-9 expression and TLR2/4 ligands release, and that targeting TLR2/4 signaling may provide an important approach in the therapeutic strategy for AIH.


Asunto(s)
Galectinas/metabolismo , Hepatitis Autoinmune/metabolismo , Hepatocitos/fisiología , Interferón gamma/metabolismo , Hígado/metabolismo , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Células Cultivadas , Hepatitis Autoinmune/inmunología , Hepatitis Autoinmune/patología , Ligandos , Hígado/patología , Ratones , Ratones Endogámicos C57BL , Transducción de Señal , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/patología , Células TH1/inmunología , Células TH1/metabolismo
18.
JSLS ; 13(1): 80-3, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19366548

RESUMEN

BACKGROUND: Lipomas are the most common benign mesenchymal tumors of the gastrointestinal tract, with the colon being the most prevalent site. Intestinal lipomas are usually asymptomatic. Tumors >2 cm in diameter may occasionally cause nonspecific symptoms, including change in bowel habits, abdominal pain, or rectal bleeding, but with resection the prognosis is excellent. Herein, we describe the case of an elderly male who presented with painless hematochezia. METHODS: Both colonoscopy and computed tomography of the abdomen and pelvis confirmed the presence of a mass near the ileocecal valve. Because of continuing bleeding, the patient required laparoscopic-assisted right hemicolectomy to resect the mass. RESULTS: Both gross and microscopic pathology were consistent with lipoma at the ileocecal valve. CONCLUSION: Previous cases of ileocecal valve lipomas have been reported in the English literature, with the majority presenting as intussusception or volvulus. We present a rare case of an ulcerated ileocecal valve lipoma presenting as lower gastrointestinal bleeding that was treated successfully with laparoscopic resection.


Asunto(s)
Colectomía/métodos , Neoplasias del Colon/cirugía , Hemorragia Gastrointestinal/cirugía , Válvula Ileocecal/patología , Lipoma/cirugía , Anciano , Neoplasias del Colon/complicaciones , Neoplasias del Colon/diagnóstico , Neoplasias del Colon/patología , Colonografía Tomográfica Computarizada , Colonoscopía , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/patología , Humanos , Lipoma/complicaciones , Lipoma/diagnóstico , Lipoma/patología , Masculino
19.
World J Gastroenterol ; 25(3): 378-387, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30686905

RESUMEN

BACKGROUND: Cirrhosis is a chronic late stage liver disease associated with hepatitis viruses, alcoholism, and metabolic disorders, such as Wilson disease (WD). There are no clear markers or clinical features that define cirrhosis originating from these disparate origins. We hypothesized that cirrhosis is not one disease and cirrhosis of different etiology may have differential clinical hepatic features. AIM: To delineate the liver features between WD-associated cirrhosis and hepatitis B-associated cirrhosis in the Chinese population. METHODS: In this observational study, we reviewed the medical data of consecutive inpatients who had WD-associated cirrhosis or hepatitis B-associated cirrhosis from January 2010 to August 2018, and excluded patients who had carcinoma, severe heart or pulmonary diseases, or other liver diseases. According to the etiology of cirrhosis, patients were divided into two groups: WD-associated cirrhosis group (60 patients) and hepatitis B-associated cirrhosis group (56 patients). The liver fibrosis degree, liver function indices, and portal hypertension features of these patients were compared between the two groups. RESULTS: No inter-group differences were observed in the diagnostic liver fibrosis markers, however, clinical features clearly defined the origin of cirrhosis. WD-associated cirrhosis patients (16-29 years) had lower levels of alanine transaminase, aspartate transaminase, and bilirubin, lower prothrombin time, lower incidence of hepatic encephalopathy, and lower portal vein diameter (P < 0.05), compared to cirrhosis resulting from hepatitis B in older patients (45-62 years). Importantly, they had decreased risks of progression from Child-Pugh grade A to B (odds ratio = 0.046, 95% confidence interval: 0.006-0.387, P = 0.005) and of ascites (odds ratio = 0.08, 95% confidence interval: 0.01-0.48, P = 0.005). Conversely, WD-associated cirrhosis patients had a higher risk of splenomegaly (odds ratio = 4.15, 95% confidence interval: 1.38-12.45, P = 0.011). CONCLUSION: WD-associated cirrhosis presents a higher risk of splenomegaly associated with leukopenia and thrombocytopenia, although revealing milder liver dysfunction and portal hypertension symptoms, which recommends WD patients to be monitored for associated complications.


Asunto(s)
Hepatitis B Crónica/complicaciones , Degeneración Hepatolenticular/complicaciones , Hipertensión Portal/etiología , Cirrosis Hepática/etiología , Hígado/patología , Adolescente , Adulto , Biomarcadores/análisis , China/epidemiología , Femenino , Hepatitis B Crónica/sangre , Hepatitis B Crónica/virología , Degeneración Hepatolenticular/sangre , Humanos , Hipertensión Portal/sangre , Hipertensión Portal/diagnóstico por imagen , Leucopenia/epidemiología , Leucopenia/etiología , Hígado/irrigación sanguínea , Hígado/diagnóstico por imagen , Hígado/virología , Cirrosis Hepática/sangre , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/virología , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Vena Porta/diagnóstico por imagen , Vena Porta/patología , Estudios Retrospectivos , Esplenomegalia/diagnóstico por imagen , Esplenomegalia/epidemiología , Esplenomegalia/etiología , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Adulto Joven
20.
Neural Regen Res ; 14(10): 1814-1822, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31169200

RESUMEN

Accumulating studies suggest that neuroinflammation characterized by microglial overactivation plays a pivotal role in the pathogenesis of Parkinson's disease. As such, inhibition of microglial overactivation might be a promising treatment strategy to delay the onset or slow the progression of Parkinson's disease. Ginsenoside Rb1, the most active ingredient of ginseng, reportedly exerts neuroprotective effects by suppressing inflammation in vitro. The present study aimed to evaluate the neuroprotective and anti-inflammatory effects of ginsenoside Rb1 in a lipopolysaccharide-induced rat Parkinson's disease model. Rats were divided into four groups. In the control group, sham-operated rats were intraperitoneally administered normal saline for 14 consecutive days. In the ginsenoside Rb1 group, ginsenoside Rb1 (20 mg/kg) was intraperitoneally injected for 14 consecutive days after sham surgery. In the lipopolysaccharide group, a single dose of lipopolysaccharide was unilaterally microinjected into the rat substantial nigra to establish the Parkinson's disease model. Lipopolysaccharide-injected rats were treated with normal saline for 14 consecutive days. In the ginsenoside Rb1 + lipopolysaccharide group, lipopolysaccharide was unilaterally microinjected into the rat substantial nigra. Subsequently, ginsenoside Rb1 was intraperitoneally injected for 14 consecutive days. To investigate the therapeutic effects of ginsenoside Rb1, behavioral tests were performed on day 15 after lipopolysaccharide injection. We found that ginsenoside Rb1 treatment remarkably reduced apomorphine-induced rotations in lipopolysaccharide-treated rats compared with the lipopolysaccharide group. To investigate the neurotoxicity of lipopolysaccharide and potential protective effect of ginsenoside Rb1, contents of dopamine and its metabolites in the striatum were measured by high-performance liquid chromatography. Compared with the lipopolysaccharide group, ginsenoside Rb1 obviously attenuated the lipopolysaccharide-induced depletion of dopamine and its metabolites in the striatum. To further explore the neuroprotective effect of ginsenoside Rb1 against lipopolysaccharide-induced neurotoxicity, immunohistochemistry and western blot assay of tyrosine hydroxylase were performed to evaluate dopaminergic neuron degeneration in the substantial nigra par compacta. The results showed that lipopolysaccharide injection caused a large loss of tyrosine hydroxylase-immunoreactive neurons in the substantia nigra and a significant decrease in overall tyrosine hydroxylase expression. However, ginsenoside Rb1 noticeably reversed these changes. To investigate whether the neuroprotective effect of ginsenoside Rb1 was associated with inhibition of lipopolysaccharide-induced microglial activation, we examined expression of the microglia marker Iba-1. Our results confirmed that lipopolysaccharide injection induced a significant increase in Iba-1 expression in the substantia nigra; however, ginsenoside Rb1 effectively suppressed lipopolysaccharide-induced microglial overactivation. To elucidate the inhibitory mechanism of ginsenoside Rb1, we examined expression levels of inflammatory mediators (tumor necrosis factor-α, interleukin-1ß, inducible nitric oxide synthase, and cyclooxygenase 2) and phosphorylation of nuclear factor kappa B signaling-related proteins (IκB, IKK) in the substantia nigra with enzyme-linked immunosorbent and western blot assays. Our results revealed that compared with the control group, phosphorylation and expression of inflammatory mediators IκB and IKK in the substantia nigra of lipopolysaccharide group rats were significantly increased; whereas, ginsenoside Rb1 obviously reduced lipopolysaccharide-induced changes on the lesioned side of the substantial nigra par compacta. These findings confirm that ginsenoside Rb1 can inhibit inflammation induced by lipopolysaccharide injection into the substantia nigra and protect dopaminergic neurons, which may be related to its inhibition of the nuclear factor kappa B signaling pathway. This study was approved by the Experimental Animal Ethics Committee of Shandong University of China in April 2016 (approval No. KYLL-2016-0148).

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