Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 274
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Ann Surg ; 280(2): 222-228, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38385254

RESUMEN

OBJECTIVE: To evaluate the effect of perioperative dexamethasone on postoperative complications after pancreaticoduodenectomy. BACKGROUND: The glucocorticoid dexamethasone has been shown to improve postoperative outcomes in surgical patients, but its effects on postoperative complications after pancreaticoduodenectomy are unclear. METHODS: This multicenter, double-blind, randomized controlled trial was conducted in four Chinese high-volume pancreatic centers. Adults undergoing elective pancreaticoduodenectomy were randomized to receive either 0.2 mg/kg dexamethasone or a saline placebo as an intravenous bolus within 5 minutes after anesthesia induction. The primary outcome was the Comprehensive Complication Index (CCI) score within 30 days after the operation, analyzed using the modified intention-to-treat principle. RESULTS: Among 428 patients for eligibility, 300 participants were randomized and 265 were included in the modified intention-to-treat analyses. One hundred thirty-four patients received dexamethasone and 131 patients received a placebo. The mean (SD) CCI score was 14.0 (17.5) in the dexamethasone group and 17.9 (20.3) in the placebo group (mean difference: -3.8; 95% CI: -8.4 to 0.7; P = 0.100). The incidence of major complications (Clavien-Dindo grade ≥III; 12.7% vs 16.0%, risk ratio: 0.79; 95% CI: 0.44 to 1.43; P = 0.439) and postoperative pancreatic fistula (25.4% vs 31.3%, risk ratio: 0.81; 95% CI: 0.55 to 1.19; P = 0.286) were not significantly different between the two groups. In the stratum of participants with a main pancreatic duct ≤3 mm (n = 202), the CCI score was significantly lower in the dexamethasone group (mean difference: -6.4; 95% CI: -11.2 to -1.6; P = 0.009). CONCLUSIONS: Perioperative dexamethasone did not significantly reduce postoperative complications within 30 days after pancreaticoduodenectomy.


Asunto(s)
Dexametasona , Pancreaticoduodenectomía , Complicaciones Posoperatorias , Humanos , Pancreaticoduodenectomía/efectos adversos , Dexametasona/uso terapéutico , Dexametasona/administración & dosificación , Masculino , Método Doble Ciego , Femenino , Complicaciones Posoperatorias/prevención & control , Persona de Mediana Edad , Anciano , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Atención Perioperativa/métodos , Resultado del Tratamiento , Adulto
2.
BMC Cancer ; 24(1): 251, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395787

RESUMEN

BACKGROUND: The occurrence of surgical site infection (SSI) after pancreaticoduodenectomy (PD) is still relatively high. The aim of this retrospective study is to evaluate the efficacy of piperacillin-tazobactam as perioperative prophylactic antibiotic on organ/space SSI for patients underwent PD. METHODS: Four hundred seven consecutive patients who underwent PD between January 2018 and December 2022 were enrolled and analyzed retrospectively. The univariate and multivariate analysis were used to identify independent risk factors of organ/space SSI. Postoperative complications were compared between the two groups according to the use of prophylactic antibiotics by a ratio of 1:1 propensity score-matched (PSM) analysis. RESULTS: Based on perioperative prophylactic antibiotic use, all 407 patients were divided into the ceftriaxone group (n = 192, 47.2%) and piperacillin-tazobactam group (n = 215, 52.8%). The rate of organ/space SSI was 31.2% with the choice of perioperative antibiotics (OR = 2.837, 95%CI = 1.802-4.465, P < 0.01) as one of independent risk factors. After PSM, there were similar baseline characteristics among the groups. Meanwhile, the piperacillin-tazobactam group had a significant lower rate of organ/space SSI compared to the ceftriaxone group both before and after PSM(P < 0.05). CONCLUSIONS: The adoption of piperacillin-tazobactam as perioperative prophylaxis for patients underwent PD reduced organ/space SSI significantly.


Asunto(s)
Profilaxis Antibiótica , Infección de la Herida Quirúrgica , Humanos , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control , Estudios Retrospectivos , Profilaxis Antibiótica/efectos adversos , Ceftriaxona , Pancreaticoduodenectomía/efectos adversos , Puntaje de Propensión , Antibacterianos/uso terapéutico , Combinación Piperacilina y Tazobactam
3.
FASEB J ; 37(10): e23217, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37738023

RESUMEN

Ubiquitination is the most common post-translational modification and is essential for various cellular regulatory processes. RNF187, which is known as RING domain AP1 coactivator-1, is a member of the RING finger family. RNF187 can promote the proliferation and migration of various tumor cells. However, whether it has a similar role in regulating spermatogonia is not clear. This study explored the role and molecular mechanism of RNF187 in a mouse spermatogonia cell line (GC-1). We found that RNF187 knockdown reduced the proliferation and migration of GC-1 cells and promoted their apoptosis. RNF187 overexpression significantly increased the proliferation and migration of GC-1 cells. In addition, we identified Keratin36/Keratin84 (KRT36/KRT84) as interactors with RNF187 by co-immunoprecipitation and mass spectrometry analyses. RNF187 promoted GC-1 cell growth by degrading KRT36/KRT84 via lysine 48-linked polyubiquitination. Subsequently, we found that KRT36 or KRT84 overexpression significantly attenuated proliferation and migration of RNF187-overexpressing GC-1 cells. In summary, our study explored the involvement of RNF187 in regulating the growth of spermatogonia via lysine 48-linked polyubiquitination-mediated degradation of KRT36/KRT84. This may provide a promising new strategy for treating infertility caused by abnormal spermatogonia development.


Asunto(s)
Lisina , Espermatogonias , Ubiquitina-Proteína Ligasas , Animales , Masculino , Ratones , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
4.
BMC Infect Dis ; 24(1): 571, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851671

RESUMEN

OBJECTIVE: In this study, we examined the value of chest CT signs combined with peripheral blood eosinophil percentage in differentiating between pulmonary paragonimiasis and tuberculous pleurisy in children. METHODS: Patients with pulmonary paragonimiasis and tuberculous pleurisy were retrospectively enrolled from January 2019 to April 2023 at the Kunming Third People's Hospital and Lincang People's Hospital. There were 69 patients with pulmonary paragonimiasis (paragonimiasis group) and 89 patients with tuberculous pleurisy (tuberculosis group). Clinical symptoms, chest CT imaging findings, and laboratory test results were analyzed. Using binary logistic regression, an imaging model of CT signs and a combined model of CT signs and eosinophils were developed to calculate and compare the differential diagnostic performance of the two models. RESULTS: CT signs were used to establish the imaging model, and the receiver operating characteristic (ROC) curve was plotted. The area under the curve (AUC) was 0.856 (95% CI: 0.799-0.913), the sensitivity was 66.7%, and the specificity was 88.9%. The combined model was established using the CT signs and eosinophil percentage, and the ROC was plotted. The AUC curve was 0.950 (95% CI: 0.919-0.980), the sensitivity was 89.9%, and the specificity was 90.1%. The differential diagnostic efficiency of the combined model was higher than that of the imaging model, and the difference in AUC was statistically significant. CONCLUSION: The combined model has a higher differential diagnosis efficiency than the imaging model in the differentiation of pulmonary paragonimiasis and tuberculous pleurisy in children. The presence of a tunnel sign on chest CT, the absence of pulmonary nodules, and an elevated percentage of peripheral blood eosinophils are indicative of pulmonary paragonimiasis in children.


Asunto(s)
Eosinófilos , Paragonimiasis , Tomografía Computarizada por Rayos X , Tuberculosis Pleural , Humanos , Paragonimiasis/diagnóstico , Paragonimiasis/diagnóstico por imagen , Masculino , Femenino , Niño , Estudios Retrospectivos , Diagnóstico Diferencial , Tuberculosis Pleural/diagnóstico , Preescolar , Adolescente , Curva ROC , Sensibilidad y Especificidad
5.
BMC Pregnancy Childbirth ; 24(1): 77, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263003

RESUMEN

OBJECTIVE: To improve the understanding of the clinical features and imaging characteristics of pregnant women with and without in-vitro fertilisation-embryo transfer combined with pulmonary tuberculosis (TB). METHODS: A retrospective analysis was conducted involving 50 patients with pregnancy who had pulmonary TB and were admitted to the Third People's Hospital of Kunming (China) between 1 January 2017 and 31 December 2021. These patients were divided into an in-vitro fertilisation and embryo transfer (IVF-ET) conception group and a natural conception group according to the conception method. The clinical and imaging data were then collected and compared. RESULTS: The mean age of the IVF-ET group (n = 13, 31.85 ± 5.84 years) was higher than in the natural conception group (n = 37, 27.05 ± 5.5 years). The proportions of fever, haematogenous TB and extrapulmonary TB in the IVF-ET group (92.31%, 84.62% and 76.92%, respectively) were higher than those in the natural conception group (40.54%,16.22%,27.03%,respectively). The percentage of patients with pregnancy who had intracranial TB (76.9%) in the IVF-ET group was higher than in the natural conception group (10.8%). The percentage of pregnancy terminations in the IVF-ET conception group (84.62%) was higher than in the natural conception group (48.65%). All the above results had statistically significant differences (p < 0.05). CONCLUSION: Overall, IVF-ET conception combined with extensive pulmonary TB lesions lead to heavy systemic toxic symptoms, severe disease and poor pregnancy outcomes. Therefore, screening for TB prior to performing IVF-ET is recommended.


Asunto(s)
Tuberculosis Pulmonar , Tuberculosis , Femenino , Humanos , Embarazo , Transferencia de Embrión , Fertilización , Estudios Retrospectivos , Estudios de Casos y Controles
6.
Hum Genet ; 142(4): 531-541, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36933034

RESUMEN

One of the most severe forms of infertility in humans, caused by gametogenic failure, is non-obstructive azoospermia (NOA). Approximately, 20-30% of men with NOA may have single-gene mutations or other genetic variables that cause this disease. While a range of single-gene mutations associated with infertility has been identified in prior whole-exome sequencing (WES) studies, current insight into the precise genetic etiology of impaired human gametogenesis remains limited. In this paper, we described a proband with NOA who experienced hereditary infertility. WES analyses identified a homozygous variant in the SUN1 (Sad1 and UNC84 domain containing 1) gene [c. 663C > A: p.Tyr221X] that segregated with infertility. SUN1 encodes a LINC complex component essential for telomeric attachment and chromosomal movement. Spermatocytes with the observed mutations were incapable of repairing double-strand DNA breaks or undergoing meiosis. This loss of SUN1 functionality contributes to significant reductions in KASH5 levels within impaired chromosomal telomere attachment to the inner nuclear membrane. Overall, our results identify a potential genetic driver of NOA pathogenesis and provide fresh insight into the role of the SUN1 protein as a regulator of prophase I progression in the context of human meiosis.


Asunto(s)
Azoospermia , Membrana Nuclear , Masculino , Humanos , Membrana Nuclear/genética , Azoospermia/patología , Proteínas Asociadas a Microtúbulos/genética , Espermatocitos/metabolismo , Espermatocitos/patología , Telómero/patología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo
7.
Mol Med ; 29(1): 95, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37434129

RESUMEN

BACKGROUND: The main cause of high mortality from sepsis is that immunosuppression leads to life-threatening organ dysfunction, and reversing immunosuppression is key to sepsis treatment. Interferon γ (IFNγ) is a potential therapy for immunosuppression of sepsis, promoting glycolysis to restore metabolic defects in monocytes, but the mechanism of treatment is unclear. METHODS: To explore the immunotherapeutic mechanism of IFNγ, this study linked the Warburg effect (aerobic glycolysis) to immunotherapy for sepsis and used cecal ligation perforation (CLP) and lipopolysaccharide (LPS) to stimulate dendritic cells (DC) to establish in vivo and in vitro sepsis models, Warburg effect inhibitors (2-DG) and PI3K pathway inhibitors (LY294002) were used to explore the mechanism by which IFNγ regulates immunosuppression in mice with sepsis through the Warburg effect. RESULTS: IFNγ markedly inhibited the reduction in cytokine secretion from lipopolysaccharide (LPS)-stimulated splenocytes. IFNγ-treated mice had significantly increased the percentages of positive costimulatory receptor CD86 on Dendritic cells expressing and expression of splenic HLA-DR. IFNγ markedly reduced DC-cell apoptosis by upregulating the expression of Bcl-2 and downregulating the expression of Bax. CLP-induced formation of regulatory T cells in the spleen was abolished in IFNγ -treated mice. IFNγ treatment reduced the expression of autophagosomes in DC cells. IFNγ significant reduce the expression of Warburg effector-related proteins PDH, LDH, Glut1, and Glut4, and promote glucose consumption, lactic acid, and intracellular ATP production. After the use of 2-DG to suppress the Warburg effect, the therapeutic effect of IFNγ was suppressed, demonstrating that IFNγ reverses immunosuppression by promoting the Warburg effect. Moreover, IFNγ increased the expression of phosphoinositide 3-kinases (PI3K), protein kinase B (Akt), rapamycin target protein (mTOR), hypoxia-inducible factor-1 (HIF-1α), pyruvate dehydrogenase kinase (PDK1) protein, the use of 2-DG and LY294002 can inhibit the expression of the above proteins, LY294002 also inhibits the therapeutic effect of IFNγ. CONCLUSIONS: It was finally proved that IFNγ promoted the Warburg effect through the PI3K/Akt/mTOR pathway to reverse the immunosuppression caused by sepsis. This study elucidates the potential mechanism of the immunotherapeutic effect of IFNγ in sepsis, providing a new target for the treatment of sepsis.


Asunto(s)
Terapia de Inmunosupresión , Interferón gamma , Sepsis , Animales , Ratones , Interferón gamma/uso terapéutico , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Sepsis/tratamiento farmacológico
8.
Mol Biol Rep ; 50(8): 6963-6974, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37358764

RESUMEN

The glucose transporter family has an important role in the initial stage of glucose metabolism; Glucose transporters 2 (GLUTs, encoded by the solute carrier family 2, SLC2A genes) is the major glucose transporter in ß-cells of pancreatic islets and hepatocytes but is also expressed in the small intestine, kidneys, and central nervous system; GLUT2 has a relatively low affinity to glucose. Under physiological conditions, GLUT2 transports glucose into cells and allows the glucose concentration to reach balance on the bilateral sides of the cellular membrane; Variation of GLUT2 is associated with various endocrine and metabolic disorders; In this study, we discussed the role of GLUT2 in participating in glucose metabolism and regulation in multiple organs and tissues and its effects on maintaining glucose homeostasis.


Asunto(s)
Glucosa , Islotes Pancreáticos , Glucosa/metabolismo , Islotes Pancreáticos/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Hepatocitos/metabolismo , Transporte Biológico , Transportador de Glucosa de Tipo 2/genética , Transportador de Glucosa de Tipo 2/metabolismo
9.
Eur Surg Res ; 64(2): 252-260, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36754029

RESUMEN

INTRODUCTION: Sarcopenia and visceral obesity have been identified as risk factors for postoperative complications following hepatobiliary and colon surgery. However, the correlation between body composition parameters and morbidity following pancreatectomy remains unclear. This study aimed to assess the predictive value of body composition parameters measured from preoperative CT images for postoperative complications following pancreaticoduodenectomy (PD). METHODS: A retrospective study of patients who underwent PD between January 2018 and January 2021 was performed. Areas of subcutaneous adipose tissue, visceral adipose tissue, total abdominal muscle area, and mean muscle radio-attenuation were measured from preoperative CT images. Postoperative complications were categorized according to the Clavien-Dindo classification, and comprehensive complication index (CCI) scores were calculated. Logistic regression analysis was performed to identify factors associated with clinically relevant postoperative pancreatic fistula (CR-POPF) and high CCI score (≥26.2). RESULTS: From the data collected on 129 study patients, sarcopenia, visceral obesity, and myosteatosis were detected in 47 (36.4%), 38 (29.4%), and 50 (38.7%) patients, respectively. CR-POPF developed in 51 (39.5%) patients, the overall median CCI score was 30.8 (22.6-36.2), and high CCI scores were identified in 70 (54.3%) patients. Multivariate analysis indicated sarcopenia and visceral obesity were independent risk variables for CR-POPF. Preoperative sarcopenia, visceral obesity, age, preoperative biliary drainage, and a positive culture of postoperative drainage were predictors of high CCI scores. CONCLUSION: Sarcopenia and visceral obesity were significant predictors of CR-POPF and high CCI score. Preoperative body composition assessment by CT images may help identify high-risk patients who undergo PD.


Asunto(s)
Pancreaticoduodenectomía , Sarcopenia , Humanos , Pancreaticoduodenectomía/efectos adversos , Pancreatectomía/efectos adversos , Sarcopenia/diagnóstico por imagen , Sarcopenia/complicaciones , Obesidad Abdominal/complicaciones , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Fístula Pancreática/etiología , Factores de Riesgo , Composición Corporal
10.
Eur Surg Res ; 64(3): 334-341, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37068477

RESUMEN

INTRODUCTION: Although the Clavien-Dindo classification (CDC) is the most widely utilized method for quantifying surgical complications, it fails to properly capture all events. To address this, the comprehensive complication index (CCI) was introduced. The purpose of this study was to compare the CCI and CDC as predictors of postoperative length of stay (PLOS) and total hospitalization costs in patients undergoing pancreaticoduodenectomy (PD). METHODS: Data were collected from February 2018 to February 2021. Complications were graded on the CDC scale and the CCI was calculated for each patient. The correlations between CDC and CCI with PLOS and hospitalization costs were compared. Linear analyses were performed to identify factors associated with PLOS and costs. RESULTS: 291 patients were enrolled with an average age of 61.2 years. 286 of them developed postoperative complications at CDC grade 1 (17.8%), 2 (59.9%), 3a (13.4%), 3b (4.5%), 4 (2.1%), and 5 (0.6%). Median CCI of the study cohort was 30.8. Spearman's correlation analysis showed the CDC and CCI were significantly correlated with PLOS and hospitalization costs, but the CCI showed a stronger correlation with PLOS (+0.552 day of stay for each additional CCI point; CCI: ρ = 0.663 vs. CDC: ρ = 0.581; p = 0.036). There were no significant differences in the correlations between total hospitalization costs and the CDC or CCI (CCI: ρ = 0.566 vs. CDC: ρ = 0.565; p = 0.78). CONCLUSION: CCI is an accurate tool for quantifying morbidities after PD and shows a stronger correlation with PLOS compared with the CDC.


Asunto(s)
Pancreaticoduodenectomía , Complicaciones Posoperatorias , Humanos , Persona de Mediana Edad , Pancreaticoduodenectomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Anastomosis Quirúrgica , Tiempo de Internación , Estudios Retrospectivos
11.
Anaerobe ; 83: 102787, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37827238

RESUMEN

OBJECTIVES: This study aimed to elucidate mechanistic explanation(s) for compositional changes to enteric microbiota by determining the impacts of continuous nicotine/cotinine exposure on representative gastrointestinal bacteria and how these alterations impact innate immune cell plasticity. METHODS: In vitro cultures of the gastrointestinal bacteria (Bacteroides fragilis 25285, Prevotella bryantii B14, and Acetoanaerobium sticklandii SR) were continuously exposed to nicotine or cotinine. Supernatant samples were collected for fermentation acid analysis. Vesicles were collected and analyzed for physiological changes in number, size, and total protein cargo. Cultured macrophages were stimulated to a tolerogenic phenotype, exposed to control or altered (nicotine or cotinine - exposed) vesicles, and inflammatory plasticity assessed via inflammatory cytokine production. RESULTS: Nicotine/cotinine exposure differentially affected metabolism of all bacteria tested in a Gram (nicotine) and concentration-dependent (cotinine) manner. Physiological studies demonstrated changes in vesiculation number and protein cargo following nicotine/cotinine exposures. Continuous exposure to 1 µM nicotine and 10 µM cotinine concentrations reduced total protein cargo of Gram (-) - 25285 and B14 vesicles, while cotinine generally increased total protein in Gram (+) - SR vesicles. We found that theses physiological changes to the vesicles of 25285 and SR formed under nicotine and cotinine, respectively, challenged the plasticity of tolerogenic macrophages. Tolerogenic macrophages exposed to vesicles from 1 µM nicotine, and 5 or 10 µΜ cotinine cultures produced significantly less IL-12p70, TNFα, or KC/GRO, regardless of macrophage exposure to nicotine/cotinine. CONCLUSIONS: Nicotine/cotinine exposure differentially alters bacterial metabolism and vesicle physiology, ultimately impacting the inflammatory response of tolerogenic macrophages.


Asunto(s)
Cotinina , Nicotina , Nicotina/farmacología , Nicotina/análisis , Nicotina/metabolismo , Cotinina/análisis , Cotinina/metabolismo , Macrófagos/metabolismo , Bacterias/metabolismo
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(1): 198-202, 2023 Jan.
Artículo en Zh | MEDLINE | ID: mdl-36647667

RESUMEN

Objective: To prepare cell membrane nanovesicles (NVs) derived from breast cancer cells, to explore their basic characteristics, tumor cell endocytosis, and in vivo distribution in a tumor-bearing mouse model, and to investigate their tumor targeting properties. Methods: 4T1 breast cancer cells were cultured in vitro. The cell membrane of 4T1 cells was isolated through ultracentrifugation and NVs were formulated with a liposome extruder. The size distribution of NVs was determined by way of dynamic light scattering, and the morphology properties of the NVs were examined with transmission electron microscope. The stability of NVs was analyzed by measuring the diameter changes of NVs submerged in phosphate-buffered saline (PBS). The biocompatibility of NVs was investigated by measuring the viability of dendritic cells treated with NVs at different concentrations (5, 10, 20, 50, and 100 mg·L -1) by CCK-8 assay. Fluorescence microscopy was used to analyze the cellular uptake of NVs by breast cancer cells. A mice model of breast cancer model was established with mice bearing subcutaneous xenograft of 4T1 cells. The mice were treated with Cy5.5-labeled NVs injected via the tail vein and the in vivo distribution of NVs was analyzed with an imaging system for small live animals. Results: The results showed that NVs derived from 4T1 breast cancer cells were successfully prepared. The NVs had a mean diameter of 123.2 nm and exhibited a hollow spherical structure under transmission electron microscope. No obvious change in the size of the NVs was observed after 7 days of incubation in PBS solution. CCK-8 assay results showed that the viability of dendritic cells treated with NVs at different concentrations was always higher than 90%. Fluorescence microscopic imaging showed that NVs could be efficiently internalized into breast cancer cells. in vivo biodistribution analysis revealed that breast cancer cell-derived NVs showed higher distribution in tumor tissue than the NVs prepared with normal cells did. Conclusion: We successfully prepared cell membrane NVs derived from 4T1 breast cancer cells. These NVs had efficient cellular uptake by breast cancer cells and sound tumor targeting properties.


Asunto(s)
Neoplasias de la Mama , Humanos , Ratones , Animales , Femenino , Distribución Tisular , Membrana Celular/metabolismo , Línea Celular Tumoral , Liposomas , Neoplasias de la Mama/metabolismo
13.
Langmuir ; 38(19): 6209-6216, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35508432

RESUMEN

Probing the adlayer structures on an electrode/electrolyte interface is one of the most important tasks in modern electrochemistry for clarifying the electrochemical processes. Herein, we have combined cyclic voltammetry and electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy techniques to explore the potential-dependent adlayer structures on Au(111) in a room-temperature ionic liquid of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIPF6) without or with pyridine (Py). It is clearly found that the BMI+ cations strongly adsorb on the negatively charged surface with a flat-lying orientation, leaving a little space for Py adsorption. Upon increasing the potentials of the electrode, the variations of Raman band intensities and frequencies reveal that the interaction between the BMI+ cations and the Au surface becomes weak; meanwhile, the Py adsorption becomes strong, and its geometry turns from flat, tilted to vertical. Finally, BMI+ cations desorb and leave plenty of surface sites for Py adsorption in bulk solution, and a N-bonded compact Py adlayer is formed on the very positively charged surface. This causes obvious anodic peaks in cyclic voltammograms, and the peak currents increase with the square root of the scanning rate. The present work provides a fair molecular-level understanding of electrochemical interfaces and molecular adsorption of Py in ionic liquids.

14.
Analyst ; 147(7): 1341-1347, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35244130

RESUMEN

The electroreductive cleavage of carbon-halogen bonds has attracted increasing attention in both electrosynthesis and pollution remediation. Herein, by employing the in situ electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique, we have successfully investigated the electroreductive dehalogenation process of aryl halides with the thiol group on a smooth Au electrode in aqueous solution at different pH values. The obtained potential-dependent Raman spectra directly reveal a mixture of the reduction products 4,4'-biphenyldithiol (BPDT) and thiophenol (TP). The conversion ratios of the C-Cl and C-Br bonds at pH = 7 are 37% and 55%, respectively. Furthermore, quantitative analysis of the intensity variations of ν(C-Cl), ν(C-Br) and aromatic ν(CC) stretching modes suggests electroreductive dehalogenation via both direct electron transfer reduction and electrocatalytic hydrodehalogenation. Molecular evidence for the C-C cross coupling process through TP reaction with benzene free radical intermediates is found at negative potentials, which leads to the increasing selectivity of biphenyl products.

15.
BMC Gastroenterol ; 22(1): 51, 2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35125104

RESUMEN

BACKGROUND: Postoperative pancreatic fistula (POPF) is a frequent complication after pancreaticoduodenectomy (PD). This study aimed to investigate the impact of Vater's ampullary carcinoma (VAC) on clinically relevant POPF (CR-POPF) in patients undergoing PD. METHODS: Clinical data were gathered retrospectively from January 2018 to December 2020 for all patients undergoing PD. The univariate and multivariate analysis were used to identify independent risk factors of CR-POPF. A propensity score-matched (PSM) analysis at a ratio of 1:1 was performed to minimize bias from baseline characteristics between VAC and non-VAC groups. Main postoperative complications were compared between the two groups after PSM. RESULTS: In 263 patients, 94 (35.7%) patients were diagnosed as VAC. CR-POPF occurred in 99 (37.6%) patients and VAC was identified as an independent risk factor of CR-POPF in multivariate logistic regression analysis (OR = 0.548, 95% CI = 0.327-0.920, P = 0.023). After PSM, there were similar baseline characteristics between the VAC and non-VAC group. Moreover, VAC group had a higher rate of CR-POPF (P = 0.025) and intra-abdominal infection (P = 0.015) compared to the non-VAC group. CONCLUSIONS: In patients undergoing PD, VAC increases the risk of CR-POPF and several other postoperative complications.


Asunto(s)
Ampolla Hepatopancreática , Fístula Pancreática , Ampolla Hepatopancreática/cirugía , Humanos , Fístula Pancreática/epidemiología , Fístula Pancreática/etiología , Fístula Pancreática/cirugía , Pancreaticoduodenectomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Puntaje de Propensión , Estudios Retrospectivos , Factores de Riesgo
16.
Glia ; 69(8): 2037-2053, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33851731

RESUMEN

Nicotine is a highly addictive compound present in tobacco, which causes the release of dopamine in different regions of the brain. Recent studies have shown that astrocytes express nicotinic acetylcholine receptors (nAChRs) and mediate calcium signaling. In this study, we examine the morphological and functional adaptations of astrocytes due to nicotine exposure. Utilizing a combination of fluorescence and atomic force microscopy, we show that nicotine-treated astrocytes exhibit time-dependent remodeling in the number and length of both proximal and fine processes. Blocking nAChR activity with an antagonist completely abolishes nicotine's influence on astrocyte morphology indicating that nicotine's action is mediated by these receptors. Functional studies show that 24-hr nicotine treatment induces higher levels of calcium activity in both the cell soma and the processes with a more substantial change observed in the processes. Nicotine does not induce reactive astrocytosis even at high concentrations (10 µM) as determined by cytokine release and glial fibrillary acidic protein expression. We designed tissue clearing experiments to test whether morphological changes occur in vivo using astrocyte specific Aldh1l1-tdTomato knock in mice. We find that nicotine induces a change in the volume of astrocytes in the prefrontal cortex, CA1 of the hippocampus, and the substantia nigra. These results indicate that nicotine directly alters the functional and morphological properties of astrocytes potentially contributing to the underlying mechanism of nicotine abuse.


Asunto(s)
Nicotina , Receptores Nicotínicos , Animales , Astrocitos/metabolismo , Dopamina/metabolismo , Ratones , Nicotina/metabolismo , Nicotina/farmacología , Agonistas Nicotínicos/metabolismo , Agonistas Nicotínicos/farmacología
17.
Cancer Cell Int ; 21(1): 371, 2021 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-34253205

RESUMEN

BACKGROUND: Programmed death- ligand 1 (PD-L1) seems to be associated with the immune escape of tumors, and immunotherapy may be a favorable treatment for PD-L1-positive patients. We evaluated intrahepatic cholangiocarcinoma (ICC) specimens for their expression of PD-L1, infiltration of CD8+ T cells, and the relationship between these factors and patient survival. METHODS: In total, 69 resections of ICC were stained by immunohistochemistry for PD-L1, programmed death factor-1 (PD-1), and CD8+ T cells. CD8+ T-cell densities were analyzed both within tumors and at the tumor-stromal interface. Patient survival was predicted based on the PD-L1 status and CD8+ T-cell density. RESULTS: The expression rate of PD-L1 was 12% in cancer cells and 51% in interstitial cells. The expression rate of PD-1 was 30%, and the number of CD8+ T-cells increased with the increase of PD-L1 expression (p < 0.05). The expression of PD-L1 in the tumor was correlated with poor overall survival(OS) (p = 0.004), and the number of tumor and interstitial CD8+ T-cells was correlated with poor OS and disease-free survival (DFS) (All p < 0.001). CONCLUSIONS: The expression of PD-L1 in the tumor is related to poor OS, and the number of tumor or interstitial CD8+ T-cells is related to poor OS and DFS. For patients who lose their chance of surgery, PD-L1 immunosuppressive therapy may be the focus of future research as a potential treatment.

18.
Neoplasma ; 68(6): 1147-1156, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34427100

RESUMEN

The cystine/glutamate antiporter xCT (SLC7A11) is frequently upregulated in many cancers, including glioblastoma (GBM). SLC7A11-mediated cystine taken up is reduced to cysteine, a precursor amino acid for glutathione synthesis and antioxidant cellular defense. However, little is known about the biological functions of SLC7A11 and its effect on therapeutic response in GBM. Here, we report that the expression of SLC7A11 is higher in GBM compared with normal brain tissue, but is negatively associated with tumor grades and positively impacts survival in the bioinformatic analysis of TCGA and CGGA database. Additionally, a negative association between SLC7A11 and mismatch repair (MMR) gene expression was identified by Pearson correlation analysis. In the GBM cells with glucose-limited culture conditions, overexpression of SLC7A11 significantly decreased MMR gene expression, including MLH1, MSH6, and EXO1. SLC7A11-overexpressed GBM cells demonstrated elevated double-strand break (DSB) levels and increased sensitivity to radiation treatment. Taken together, our work indicates that SLC7A11 might be a potential biomarker for predicting a better response to radiotherapy in GBM.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Reparación de la Incompatibilidad de ADN , Glioblastoma , Sistema de Transporte de Aminoácidos y+/genética , Sistema de Transporte de Aminoácidos y+/metabolismo , Línea Celular Tumoral , Expresión Génica , Glioblastoma/genética , Glioblastoma/radioterapia , Glucosa , Humanos
19.
Sensors (Basel) ; 21(19)2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34641016

RESUMEN

In recent years, intelligent fault diagnosis methods based on deep learning have developed rapidly. However, most of the existing work performs well under the assumption that training and testing samples are collected from the same distribution, and the performance drops sharply when the data distribution changes. For rolling bearings, the data distribution will change when the load and speed change. In this article, to improve fault diagnosis accuracy and anti-noise ability under different working loads, a transfer learning method based on multi-scale capsule attention network and joint distributed optimal transport (MSCAN-JDOT) is proposed for bearing fault diagnosis under different loads. Because multi-scale capsule attention networks can improve feature expression ability and anti-noise performance, the fault data can be better expressed. Using the domain adaptation ability of joint distribution optimal transport, the feature distribution of fault data under different loads is aligned, and domain-invariant features are learned. Through experiments that investigate bearings fault diagnosis under different loads, the effectiveness of MSCAN-JDOT is verified; the fault diagnosis accuracy is higher than that of other methods. In addition, fault diagnosis experiment is carried out in different noise environments to demonstrate MSCAN-JDOT, which achieves a better anti-noise ability than other transfer learning methods.

20.
Nano Lett ; 20(8): 6135-6141, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32628854

RESUMEN

We present the application of multiphoton in vivo fluorescence correlation spectroscopy (FCS) of fluorescent nanoparticles for the measurement of cerebral blood flow with excellent spatial and temporal resolution. Through the detection of single nanoparticles within the complex vessel architecture of a live mouse, this new approach enables the quantification of nanoparticle dynamics occurring within the vasculature along with simultaneous measurements of blood flow properties in the brain. In addition to providing high resolution blood flow measurements, this approach enables real-time quantification of nanoparticle concentration, degradation, and transport. This method is capable of quantifying flow rates at each pixel with submicron resolution to enable monitoring of dynamic changes in flow rates in response to changes in the animal's physiological condition. Scanning the excitation beam using FCS provides pixel by pixel mapping of flow rates with subvessel resolution across capillaries 300 µm deep in the brains of mice.


Asunto(s)
Microscopía de Fluorescencia por Excitación Multifotónica , Nanopartículas , Animales , Circulación Cerebrovascular , Ratones , Espectrometría de Fluorescencia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA