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1.
Biochem Biophys Res Commun ; 656: 30-37, 2023 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-36947964

RESUMEN

The widespread adoption of chimeric antigen receptor (CAR)-T cell therapy has been hindered by its complex and costly manufacturing process. Induced pluripotent stem cells (iPSCs) have shown promise as a cellular immunotherapy alternative, due to their unlimited self-renewal potential in culture and capacity to differentiate into functional immune cell types. However, it is imperative to carefully select the original cell for iPSC seed preparation, as iPSCs have been found to retain the epigenetic imprint of the original somatic cells. Additionally, the efficiency of reprogramming terminal differentiated cells for immunotherapy must be addressed. Our research highlights the superiority of lymphocyte-origin cells over embryonic stem cells in functional immune cell differentiation. Furthermore, blocking Fas-FasL induced apoptosis in T cells significantly improves iPSC generation. Interestingly, transient Fas suppression in T cells does not alter the expression of Fas in the resulting iPSCs or affect their differentiation potential. This finding brings up new avenues in the field of cellular immunotherapy and provides a solution for creating high-quality and suitable iPSCs for lymphocyte differentiation for immunotherapy purposes.


Asunto(s)
Células Madre Pluripotentes Inducidas , Reprogramación Celular , Linfocitos T , Diferenciación Celular
2.
Opt Lett ; 48(10): 2748-2751, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37186756

RESUMEN

Anisotropic two-dimensional (2D) materials, such as black phosphorus (BP), normally possess unique directional in-plane electrical, optical, and thermal properties that are highly correlated with their crystalline orientations. Nondestructive visualization of their crystalline orientation is an indispensable premise for the 2D materials to harness their distinctive strengths in optoelectronic and thermoelectric applications. Here, by photoacoustically recording the anisotropic optical absorption variation under linearly polarized laser beams, an angle-resolved polarized photoacoustic microscopy (AnR-PPAM) is developed, capable of non-invasively determining and visualizing BP's crystalline orientation. We theoretically deduced the physical relationship between the crystalline orientation and polarized photoacoustic (PA) signals, and experimentally proved the ability of AnR-PPAM to universally visualize BP's crystalline orientation regardless of its thickness, substrate, and encapsulation layer. This method provides a new, to the best of our knowledge, strategy for crystalline orientation recognition of 2D materials with flexible measurement conditions, prefiguring important potential for the applications of anisotropic 2D materials.

3.
Opt Lett ; 48(7): 1718-1721, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221749

RESUMEN

Photoacoustic microscopy (PAM) has attracted increasing research interest in the biomedical field due to its unique merit of combining light and sound. In general, the bandwidth of a photoacoustic signal reaches up to tens or even hundreds of MHz, which requires a high-performance acquisition card to meet the high requirement of precision of sampling and control. For most depth-insensitive scenes, it is complex and costly to capture the photoacoustic maximum amplitude projection (MAP) images. Herein, we propose a simple and low-cost MAP-PAM system based on a custom-made peak holding circuit to obtain the extremum values by Hz data sampling. The dynamic range of the input signal is 0.01-2.5 V, and the -6-dB bandwidth of the input signal can be up to 45 MHz. Through in vitro and in vivo experiments, we have verified that the system has the same imaging ability as conventional PAM. Owing to its compact size and ultra-low price (approximately $18), it provides a new performance paradigm for PAM and opens up a new way for an optimal photoacoustic sensing and imaging device.

4.
Eur Spine J ; 32(3): 1068-1076, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36717400

RESUMEN

PURPOSE: To investigate the imaging characteristics of thoracic ossification of ligamentum flavum (OLF) combined with dural ossification (DO) and the clinical efficacy of zoning laminectomy. METHOD: The clinical data of 48 patients with thoracic OLF combined with DO who underwent zoning laminectomy between June 2016 and May 2020 were retrospectively analyzed. The modified Japanese Orthopedic Association (mJOA) score was used to evaluate neurological function before and after surgery, and the clinical efficacy was evaluated according to the improvement rate. RESULTS: The symptoms of all patients significantly improved after the operation, and the average follow-up time was 27.8 (10-47) months. In addition, the average mJOA score had increased from 5.0 (2-8) preoperatively to 8.7 (6-11) postoperatively (t = 18.880, P < 0.05). The average improvement rate was 62.6% (25-100%), with 16 patients graded as excellent, 21 as good, and 11 as fair. Cerebrospinal fluid leakage occurred in 12 cases (25.0%), and all of them healed well after treatment. No postoperative aggravation of neurological dysfunction, wound infection or hematoma occurred. At the last follow-up, there was no recurrence of symptoms and kyphosis. CONCLUSION: The Zoning laminectomy described here is both safe and effective.


Asunto(s)
Ligamento Amarillo , Osificación Heterotópica , Humanos , Descompresión Quirúrgica/métodos , Osteogénesis , Ligamento Amarillo/diagnóstico por imagen , Ligamento Amarillo/cirugía , Estudios Retrospectivos , Osificación Heterotópica/diagnóstico por imagen , Osificación Heterotópica/cirugía , Osificación Heterotópica/complicaciones , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía
5.
Br J Clin Pharmacol ; 88(6): 2747-2756, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34964162

RESUMEN

AIMS: The mortality of critically ill patients undergoing mechanical ventilation (MV) is high and few strategies are available. We explored the relationship between ondansetron pre-treatment, the neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR), and mortality of ventilated patients in the intensive care unit. METHODS: We developed a retrospective cohort study that involved patients undergoing MV in the Multiparameter Intelligent Monitoring in Intensive Care IV (MIMIC-IV) database. Causal mediation analysis was conducted to assess the relationship of ondansetron use and mortality and to explore the potential causal pathway mediated by the NLR or PLR. The primary outcome was 28-day mortality. RESULTS: A total of 17 927 eligible patients took part in the study (5665 had taken ondansetron before MV initiation and 12 262 patients had not). The odds ratio (OR) for 28-day mortality for ondansetron use uncorrelated with the mediator (NLR, PLR) was 0.72 (95% confidence interval [CI] = 0.64-0.81, P < .001). Ondansetron was also associated with a reduction in 28-day mortality after controlling for the mediator of NLR (OR = 0.98, 95% CI = 0.97-0.99, P < .01). For the indirect effect, the NLR could explain 13.47% (95% CI = 8.59-20.54%, P < .01) of the impact of ondansetron use on 28-day mortality. The proportion mediated increased to 21.50% (95% CI = 12.36-47.44%, P < .01) for 90-day mortality. Adjusted mediation analysis revealed no suggestion of a causal mediation pathway for this effect by the PLR (P = .12). CONCLUSIONS: NLR may play substantial roles in the relationship between ondansetron pre-treatment before initiation of mechanical ventilation and the reduction of death risk in ventilated patients.


Asunto(s)
Neutrófilos , Respiración Artificial , Cuidados Críticos , Humanos , Unidades de Cuidados Intensivos , Linfocitos , Análisis de Mediación , Neutrófilos/metabolismo , Ondansetrón/uso terapéutico , Recuento de Plaquetas , Pronóstico , Estudios Retrospectivos
6.
Gynecol Endocrinol ; 38(6): 499-502, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35532201

RESUMEN

OBJECTIVE: This study aimed to investigate serum levels of adiponectin, and the mRNA expression of forkhead box C2 (FOXC2) and glucose transporter-4 (GLUT4) in visceral adipose tissue obtained from patients with gestational diabetes mellitus (GDM) and healthy pregnant women. METHODS: Venous blood samples were obtained from 60 pregnant women with gestational normal glucose tolerance (GNGT) and 21 patients with GDM. Visceral adipose tissues were obtained from 11 women with GDM and 30 with GNGT. Serum adiponectin levels were detected by enzyme-linked immunosorbent assay, and FOXC2 and GLUT4 mRNA expression were detected by quantitative polymerase chain reaction. RESULTS: Serum adiponectin concentrations were lower in the women with GDM than in the controls (p < .05). FOXC2 and GLUT4 mRNA expression were decreased in visceral adipose tissue of GDM women than in the controls (p < .05). Correlation analyses showed that FOXC2 tended to have a positive correlation with GLUT4 in GDM patients' visceral adipose tissue (p =.0564). CONCLUSION: Our results revealed that decreased adiponectin, FOXC2, and GLUT4 expression were associated with increased risk of GDM and the regulation mechanism of GLUT4 mediated by FOXC2 would be the focus of further studies.


Asunto(s)
Diabetes Gestacional , Resistencia a la Insulina , Adiponectina , Femenino , Humanos , Insulina , Resistencia a la Insulina/fisiología , Grasa Intraabdominal/metabolismo , Embarazo , ARN Mensajero/metabolismo
7.
Cell Biol Int ; 45(10): 2107-2117, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34288216

RESUMEN

Inflammation is a common pathophysiological process as well as a clinical threat that occurs in various diseases worldwide. It is well-documented that nuclear factor-κB (NF-κB) and mitogen-activated protein kinase pathways are involved in inflammatory reactions to microbial infections in lipopolysaccharide (LPS)-activated macrophages. The deubiquitinase ubiquitin carboxyl-terminal hydrolase-L1 (UCHL1) has been reported as an oncoprotein to promote the growth and progression of cancer cells. However, the regulatory mechanism of UCHL1 in inflammation is currently unclear. Here, we aimed to assess the effects of UCHL1 on LPS-associated inflammatory response in vitro and in vivo by enzyme-linked immunosorbent assay, quantitative reverse-transcription polymerase chain reaction, and western blot analysis. This study identified that inhibition or knockdown of UCHL1 decreased the amounts of the key pro-inflammatory cytokines, including interleukin-6 and tumor necrosis factor-α in macrophages. Additionally, inhibition of UCHL1 suppressed LPS-induced extracellular signal-regulated protein kinase 1/2 phosphorylation and NF-κB translocation by regulating the inhibitor of NF-κB. Mechanically, UCHL1 interacts with IκBα protein in THP-1. Meanwhile, inhibition of UCHL1 blocked the LPS-induced degradation of IκBα through the ubiquitin-proteasome system. Moreover, in vivo assay showed that suppression of UCHL1 notably reduced the LPS-induced animal death and release of pro-inflammatory cytokines. Overall, the current findings uncover that UCHL1 functions as a crucial regulator for inflammatory response via reversing the degradation of IκBα, representing a potential target for the treatment of inflammatory diseases.


Asunto(s)
Inflamación/prevención & control , Lipopolisacáridos/toxicidad , Macrófagos/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Animales , Antiinflamatorios/farmacología , Citocinas/metabolismo , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/genética , FN-kappa B/genética , Sepsis/inducido químicamente , Sepsis/metabolismo , Sepsis/patología , Sepsis/prevención & control , Transducción de Señal , Ubiquitina Tiolesterasa/genética
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(12): 1370-1374, 2021 Dec 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-35232906

RESUMEN

OBJECTIVES: The 17q12 microdeletion syndrome is a type of syndrome caused by a deletion of 1.4 to 1.8 Mb in the 17q12 region of the chromosome. The main clinical features of the syndrome are structural or functional abnormalities in the kidney and urethra, type 5 diabetes, and neurodevelopmental or neuropsychiatric disorders. The diverse range of phenotypes associated with 17q12 microdeletion limited clinical recognition and diagnosis. In addition, the phenotypic description of this microdeletion is mainly about postpartum. Due to the rarity of the 17q12 microdeletion itself, studies on the prenatal phenotype of the 17q12 microdeletion are limited. This study aims to analyze the prenatal ultrasound features of 17q12 microdeletion, and to investigate the possibility of genotype-phenotype relationship for providing evidence for genetic counseling in such pregnancies. METHODS: A total of 3 320 pregnant women and their fetuses were collected for the detection of chromosome copy number variation sequencing (CNV-Seq) due to different ultrasound anomalies in Xiangya Hospital of Central South University. The clinical data of pregnant women and their fetuses who were found to harbor 17q12 microdeletion were reviewed, including maternal age, fetus ultrasound findings, gestational week of the invasive procedure, CNV-Seq results, and the pregnancy outcome. CNV-Seq was tested in the parents to verify whether the abnormality was de novo or inherited. The prenatal ultrasound features and CNV-Seq test results of these 12 fetuses were analyzed and their pregnancy outcomes were followed up. RESULTS: Approximately 0.36% (12/3 320) of fetuses were detected to have 17q12 microdeletion, all characterized as renal abnormalities, accounting for 4.2% (12/288) of all prenatal ultrasound with renal abnormalities, accounting for 48% (12/25) of prenatal ultrasound with renal abnormalities and pathogenic chromosomal abnormalities. The sizes of 17q12 deletion ranged from 1.4 to 1.7 Mb, and all of them included the HNF1B gene. Nine cases were de novo, 2 inherited from the mother, and 1 inherited from father. Among 12 fetuses with 17q12 deletion, 11 cases of prenatal ultrasound suggested bilateral hyperechogenic kidneys and 1 case only showed renal cyst, in which 3 fetuses with enlarged kidneys, 1 with clubfeet, and 1 with subependymal cyst. Pregnancy outcomes were available for 11 of the 12 fetuses. Of them, the parents of 9 fetuses with de novo deletion chose to terminate the pregnancy, and 2 live birth babies inherited from their mother with normal renal function had persistent renal echogenicity enhancement after birth. CONCLUSIONS: Bilateral hyperechogenic kidneys show strikingly correlation with 17q12 microdeletion, suggesting the necessity of chromosome copy numbers detection for fetuses with hyperechogenic kidneys.


Asunto(s)
Variaciones en el Número de Copia de ADN , Anomalías Urogenitales , Deleción Cromosómica , Femenino , Pruebas Genéticas , Humanos , Embarazo , Diagnóstico Prenatal , Ultrasonografía Prenatal
9.
Cell Physiol Biochem ; 45(6): 2421-2430, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29554646

RESUMEN

BACKGROUND/AIMS: Cardiac hypertrophy is a major outcome and compensatory response of the cardiovascular system to hemodynamic and additional stress responses that ultimately lead to heart failure. Auranofin (Aur) has been used for treating rheumatic arthritis for several decades. Aur is a 19S proteasome-associated deubiquitinase inhibitor, and inhibition of the proteasome is speculated to reverse cardiac hypertrophy. However, the role of the deubiquitinases, especially 19S proteasome-associated deubiquitinases, in the regulation of cardiac remodeling remains poorly understood. The present study investigated the role of Aur in cardiac hypertrophy both in vitro and in vivo. METHODS: Male Sprague-Dawley rats underwent abdominal aortic constriction to induce left ventricular hypertrophy. The neonatal rat primary myocardial cell hypertrophy model was induced by Ang II. Echocardiography, hematoxylin-eosin staining, Masson's trichrome staining, immunochemistry, western blot analysis, a cell viability assay, and enzyme-linked immunosorbent assay were performed. RESULTS: Aur significantly reduced the abdominal aortic constriction that led to left ventricular hypertrophy, reduced heart cavity expansion, and functional disorder, and thereby reduced fetal gene expression and attenuated cardiac fibrosis. Furthermore, Aur caused marked accumulation of ubiquitinated proteins and IκBα, as well as inactivation of NF-κB. This phenomenon was confirmed in the neonatal rat primary myocardial cell hypertrophy model. CONCLUSIONS: The present study indicated that Aur blocks the development of left ventricular hypertrophy induced by abdominal aortic constriction. This phenomenon might be attributed to inhibition of the 19S proteasome-associated deubiquitinase that can lead to aggregation of IκBα and inactivation of the NF-κB pathway. Thus, Aur could be a potential anti-cardiac hypertrophy agent.


Asunto(s)
Antirreumáticos/uso terapéutico , Auranofina/uso terapéutico , Cardiomegalia/tratamiento farmacológico , Enzimas Desubicuitinizantes/antagonistas & inhibidores , FN-kappa B/antagonistas & inhibidores , Inhibidores de Proteasoma/uso terapéutico , Animales , Antirreumáticos/farmacología , Auranofina/farmacología , Cardiomegalia/metabolismo , Cardiomegalia/patología , Células Cultivadas , Enzimas Desubicuitinizantes/metabolismo , Hipertrofia Ventricular Izquierda , Masculino , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , FN-kappa B/metabolismo , Inhibidores de Proteasoma/farmacología , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos
10.
Opt Lett ; 43(21): 5267-5270, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30382984

RESUMEN

We proposed polarized photoacoustic microscopy (PPAM) for quantitative detection of a target's microscopic anisotropy based on the vectorial optical absorption by applying four linearly polarized laser beams as excitation sources. Compared to conventional photoacoustic microscopy that treats targets as isotropic absorbers, PPAM allows us to quantitatively detect the target's anisotropic features beyond optical absorption with a newly proposed parameter valued between 0 and 1. The feasibility of the method was validated by dichroic phantoms. The dichroic compound eyes of mantis shrimps were imaged in situ to demonstrate the method's capability for quantitative three-dimensional biological imaging. The PPAM method provides an effective and straightforward strategy for tissue polarimetry, prefiguring great potential for biological imaging and material inspection.

11.
Opt Lett ; 43(10): 2336-2339, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29762586

RESUMEN

We have developed a second harmonic photoacoustic microscopy (SH-PAM) for subdiffraction-limited imaging based on nonlinear thermal diffusion. When a sine-modulated Gaussian temperature field is introduced by a laser beam, the temperature dependence of the thermal diffusivity induces a nonlinear photoacoustic (PA) effect and thus results in the production of second harmonic PA signals. We demonstrate through both simulation and experiment that the second harmonic PA images can be reconstructed with a lateral resolution exceeding that of conventional optical resolution PA microscopy. The feasibility of SH-PAM was verified on phantom samples. Amphioxus zygotes and germinated pollens have been studied by SH-PAM to demonstrate its biomedical imaging capability. This method expands the scope of conventional PA imaging and opens up new possibilities for super-resolution imaging, prefiguring great potential for biological imaging and material inspection.


Asunto(s)
Embrión no Mamífero/diagnóstico por imagen , Anfioxos/embriología , Microscopía Acústica/métodos , Técnicas Fotoacústicas/métodos , Microscopía de Generación del Segundo Armónico , Difusión Térmica , Animales , Fantasmas de Imagen , Polen
12.
Mol Cell Biochem ; 431(1-2): 87-96, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28364380

RESUMEN

Persistent activation of nuclear factor B (NF-κB) is very important in the modulation of macrophages cellular response to microbial infections. The deubiquitinase USP14, which is critical for ubiquitin-mediated proteasomal degradation of proteins, is known to be involved in cancer, neurological diseases, and aging. However, the mechanism by which USP14 regulates inflammation remains unclear. Here, we demonstrated that decreasing the deubiquitinase activity of USP14 resulted in reduced lipopolysaccharides (LPS)-mediated tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 release in THP-1 and RAW264.7 cells. Meanwhile, USP14 knockdown by siRNA showed the same effects, with no cytotoxicity in THP-1 cells. Moreover, inhibiting the deubiquitinase activity of USP14 or USP14 knockdown resulted in decreased ERK1/2 and IκBα phosphorylation, increased amounts of the NF-κB inhibitor IκBα, and reduced NF-κB p65 transport from the cytoplasm into nucleus. These findings suggested that USP14 induces NF-κB activity and ERK1/2 phosphorylation triggered by microbial infection.


Asunto(s)
Lipopolisacáridos/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Factor de Transcripción ReIA/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Animales , Línea Celular Tumoral , Humanos , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Sistema de Señalización de MAP Quinasas/genética , Ratones , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Fosforilación/efectos de los fármacos , Fosforilación/genética , Células RAW 264.7 , Factor de Transcripción ReIA/genética , Ubiquitina Tiolesterasa/genética
13.
Biochem Biophys Res Commun ; 478(3): 1236-41, 2016 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-27545607

RESUMEN

Cardiac hypertrophy, a compensatory response to various stimuli in the heart, independently predicts cardiovascular ailments and related deaths. Increasing evidence indicates ubiquitin-proteasome signaling contributes to cardiac hypertrophy regulation. Here, we identified ubiquitin-specific protease 14 (USP14), a 19S proteasome associated deubiquitinase (DUB), as a novel target for cardiac hypertrophy therapy via inhibition of the GSK-3ß pathway. Indeed, USP14 expression was increased in an animal model of abdominal aorta constriction. In an angiotensin II (AngII) induced primary neonatal rat cardiomyocyte hypertrophy model, USP14 expression was increased in a time-dependent manner, and reduced USP14 deubiquitinase activity or USP14 knockdown resulted in lower expression levels of the myocardial hypertrophy specific marker ß-MHC, and subsequent decreased GSK-3ß phosphorylation. In conclusion, USP14 mediates the development of cardiac hypertrophy by promoting GSK-3ß phosphorylation, suggesting that USP14 might represent a novel therapeutic target for cardiac hypertrophy treatment.


Asunto(s)
Cardiomegalia/enzimología , Cardiomegalia/patología , Progresión de la Enfermedad , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Animales , Animales Recién Nacidos , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/patología , Biomarcadores/metabolismo , Cardiomegalia/diagnóstico por imagen , Constricción Patológica , Modelos Animales de Enfermedad , Técnicas de Silenciamiento del Gen , Ventrículos Cardíacos/patología , Masculino , Miocardio/metabolismo , Miocardio/patología , Cadenas Pesadas de Miosina/metabolismo , Fosforilación , Ratas Sprague-Dawley
14.
Opt Express ; 24(25): 28693-28703, 2016 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-27958513

RESUMEN

It has been recently demonstrated that a metallic surface with periodic grooves can support a laterally-confined surface wave called spoof plasmon polaritons (SSPPs). Here we propose a SSPPs waveguide drilled with L-shaped grooves which can support SSPPs efficiently. Dispersion relations based on the modal expansion method (MEM) are derived and discussed. Under the deep subwavelength condition, a concise formula for the dispersion relations is obtained. Our results show that the dispersion relations are sensitive to the transversal depths. The L-shaped groove is equivalent to a deeper rectangular groove, but more compact than the straight one. As an example of the applications, the rainbow-trapping effect is realized by changing the transversal depths of the L-shaped grooves.

15.
Angew Chem Int Ed Engl ; 55(39): 11897-901, 2016 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-27561950

RESUMEN

For the first time, a highly regioselective intermolecular sulfonylamidation unactivated secondary Csp(3) -H bond has been achieved using Ir(III) catalysts. The introduced N,N'-bichelating ligand plays a crucial role in enabling iridium-nitrene insertion into a secondary Csp(3) -H bond via an outer-sphere pathway. Mechanistic studies and density functional theory (DFT) calculations demonstrated that a two-electron concerted nitrene insertion was involved in this Csp(3) -H amidation process. This method tolerates a broad range of linear and branched-chain N-alkylamides, and provides efficient access to diverse γ-sulfonamido-substituted aliphatic amines.

16.
Front Nutr ; 11: 1275522, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476599

RESUMEN

Background: Soluble transferrin receptor (sTfR)/log ferritin index (sTfR Index) can be used to assess the entire spectrum of iron status, and is valuable in evaluating iron status in population studies. There is still a lack of evidence on the association between sTfR index and all-cause mortality. Object: To explore the association between sTfR index and all-cause mortality, as well as mortality due to cardiovascular disease (CVD) and cancer. Method: Data were from the National Health and Nutrition Examination Survey (NHANES) between 2003 to 2020. Participants aged 16 years and older who had complete data of serum ferritin and sTfR were included. Pregnant individuals or those with ineligible data on death or follow-up were excluded from the analysis. Baseline sTfR index was calculated by baseline sTfR/log (ferritin) and classified as three tertile. We performed the Cox proportional hazard regression to assess the association of sTfR index (both continuous and categorical scale) with all-cause and cause-specific mortality and further assess the non-linear relationship between sTfR index and the outcomes with restricted cubic spline. Result: In this study, 11,525 participants, a total of 231 (2.0%) all-cause deaths occurred during a median follow-up of 51 months. The risk of all-cause mortality, CVD-related mortality, and cancer-related mortality was higher in participants with highest tertile of sTfR index. After confounding factors adjustment, participants with highest tertile of sTfR index were associated with an increased risk of all-cause mortality (HR: 1.71, 95% CI: 1.14-2.57) as compared with lowest tertile. Additionally, sTfR index per SD increment was associated with a 25% increasing risk of all-cause mortality (HR: 1.25, 95% CI: 1.08-1.45, p = 0.003) and a 38% cancer-related mortality (HR: 1.38, 95% CI: 1.07-1.77, p = 0.018). These associations remained robust after adjusting for the serum ferritin as well as in various subgroups stratified by age, sex, smoking statue, hypertension, diabetes, and CVD. Spline analysis showed that there is approximately linear relationship between sTfR index with all-cause mortality (p for non-linear = 0.481). Moreover, ferritin was not a predictor of all-cause death after adjustment for confounding factors. Significance: This cohort study demonstrated a significant association between sTfR index increment and an increased risk of all-cause and cancer-related mortality, independent of ferritin levels.

17.
PLoS One ; 19(1): e0296303, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38215080

RESUMEN

This paper presents a study on the low-velocity impact response of lightweight steel foam concrete (LSFC) composite slabs. The LSFC composite slab consisted of a W-shaped steel plate, foam concrete and oriented strand board (OSB). Low-velocity impact tests on the LSFC composite slabs were conducted by employing an ultra-high heavy-duty drop hammer testing machine. The tests revealed the failure mode, impact force and displacement response of LSFC composite slabs. The effects of density and thickness of foam concrete and drop height on the peak impact force and energy absorption ratio were investigated. A finite element (FE) model was set up to predict the impact resistance of the LSFC composite slabs, and a good agreement between simulation and test results was achieved. In addition, an equivalent-single-degree-of-freedom (ESDOF) model was set up to predict the displacement response of the LSFC composite slabs under impact loading.


Asunto(s)
Placas Óseas , Acero , Simulación por Computador
18.
Food Chem ; 456: 139859, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38870800

RESUMEN

κ-Carrageenan (CG) was employed to mask the bitterness induced by 50% KCl in surimi gels to achieve salt reduction and gel performance improvement. The combination of KCl and CG (KCl + CG) yielded the increased textural characteristics and water-holding capacity (WHC) of surimi gels and facilitated the transition of free water to immobilized water. In addition, the KCl + CG supplement increased the turbidity and particle size of myofibrillar protein (MP) sols but decreased the surface hydrophobicity in a dose-dependent manner. The hydrophobic interactions and disulfide bonds played crucial roles in maintaining the stability of MP gels. The specific binding of potassium ions to the sulfate groups of CG limited the release and diffusion of potassium ions from the surimi gels during oral processing, effectively masking the bitterness perception and maintaining the saltiness perception. This study provides a promising strategy to reduce the utilization of sodium salt in surimi products.

19.
BMJ Open ; 14(6): e079212, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858161

RESUMEN

INTRODUCTION: Severe septic cardiomyopathy (SCM) is one of the main causes of refractory septic shock (RSS), with a high mortality. The application of venoarterial extracorporeal membrane oxygenation (ECMO) to support the impaired cardiac function in patients with septic shock remains controversial. Moreover, no prospective studies have been taken to address whether venoarterial ECMO treatment could improve the outcome of patients with sepsis-induced cardiogenic shock. The objective of this study is to assess whether venoarterial ECMO treatment can improve the 30-day survival rate of patients with sepsis-induced refractory cardiogenic shock. METHODS AND ANALYSIS: ExtraCorporeal Membrane Oxygenation in the therapy for REfractory Septic shock with Cardiac function Under Estimated is a prospective, multicentre, non-randomised, cohort study on the application of ECMO in SCM. At least 64 patients with SCM and RSS will be enrolled in an estimated ratio of 1:1.5. Participants taking venoarterial ECMO during the period of study are referred to as cohort 1, and patients receiving only conventional therapy without ECMO belong to cohort 2. The primary outcome is survival in a 30-day follow-up period. Other end points include survival to intensive care unit (ICU) discharge, hospital survival, 6-month survival, quality of life for long-term survival (EQ-5D score), successful rate of ECMO weaning, long-term survivors' cardiac function, the number of days alive without continuous renal replacement therapy, mechanical ventilation and vasopressor, ICU and hospital length of stay, the rate of complications potentially related to ECMO treatment. ETHICS AND DISSEMINATION: The trial has been approved by the Clinical Research and Application Institutional Review Board of the Second Affiliated Hospital of Guangzhou Medical University (2020-hs-51). Participants will be screened and enrolled from ICU patients with septic shock by clinicians, with no public advertisement for recruitment. Results will be disseminated in research journals and through conference presentations. TRIAL REGISTRATION NUMBER: NCT05184296.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Choque Cardiogénico , Choque Séptico , Oxigenación por Membrana Extracorpórea/métodos , Humanos , Choque Séptico/terapia , Choque Séptico/mortalidad , Choque Séptico/complicaciones , Estudios Prospectivos , Choque Cardiogénico/terapia , Choque Cardiogénico/mortalidad , Cardiomiopatías/terapia , Estudios Multicéntricos como Asunto , Masculino , Unidades de Cuidados Intensivos , Femenino , Adulto , Tasa de Supervivencia
20.
J Cell Physiol ; 228(12): 2324-36, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23696417

RESUMEN

miRNAs have recently been shown to play a significant role in human aging. However, data demonstrating the effects of aging-related miRNAs in human mesenchymal stem cells (hMSCs) are limited. We observed that hMSC differentiation decreased with aging. We also identified that miR-10a expression was significantly decreased with age by comparing the miRNA expression of hMSCs derived from young and aged individuals. Therefore, we hypothesized that the downregulation of miR-10a may be associated with the decreased differentiation capability of hMSCs from aged individuals. Lentiviral constructs were used to up- or downregulate miR-10a in young and old hMSCs. Upregulation of miR-10a resulted in increased differentiation to adipogenic, osteogenic, and chondrogenic lineages and in reduced cell senescence. Conversely, downregulation of miR-10a resulted in decreased cell differentiation and increased cell senescence. A chimeric luciferase reporter system was generated, tagged with the full-length 3'-UTR region of KLF4 harboring the seed-matched sequence with or without four nucleotide mutations. These constructs were cotransfected with the miR-10a mimic into cells. The luciferase activity was significantly repressed by the miR-10a mimic, proving the direct binding of miR-10a to the 3'-UTR of KLF4. Direct suppression of KLF4 in aged hMSCs increased cell differentiation and decreased cell senescence. In conclusion, miR-10a restores the differentiation capability of aged hMSCs through repression of KLF4. Aging-related miRNAs may have broad applications in the restoration of cell dysfunction caused by aging.


Asunto(s)
Factores de Transcripción de Tipo Kruppel/genética , Células Madre Mesenquimatosas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Regiones no Traducidas 3' , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diferenciación Celular/fisiología , Senescencia Celular/genética , Regulación hacia Abajo , Femenino , Humanos , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Masculino , Mutación , Nucleótidos/genética , Regulación hacia Arriba , Adulto Joven
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