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1.
EMBO J ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39060516

RESUMEN

Ageing and fertility are intertwined. Germline loss extends the lifespan in various organisms, termed gonadal longevity. However, the original longevity signal from the somatic gonad remains poorly understood. Here, we focused on the interaction between germline stem cells (GSCs) and their niche, the distal tip cells (DTCs), to explore the barely known longevity signal from the somatic gonad in C. elegans. We found that removing germline disrupts the cell adhesions between GSC and DTC, causing a significant transcriptomic change in DTC through hmp-2/ß-catenin and two GATA transcription factors, elt-3 and pqm-1 in this niche cell. Inhibiting elt-3 and pqm-1 in DTC suppresses gonadal longevity. Moreover, we further identified the TGF-ß ligand, tig-2, as the cytokine from DTC upon the loss of germline, which evokes the downstream gonadal longevity signalling throughout the body. Our findings thus reveal the source of the longevity signalling in response to germline removal, highlighting the stem cell niche as a critical signalling hub in ageing.

2.
Langmuir ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39021329

RESUMEN

This research delves into the preparation of heteronuclear bimetallic catalysts and explores their catalytic properties in the thermal decomposition of ammonium perchlorate (AP). The study's central focus is on enhancing the thermal decomposition characteristics of AP and, consequently, the combustion performance of composite solid propellants. The synthesized materials underwent structural characterization by XRD, XPS, SEM, and FTIR. Catalytic properties were examined using DTA tests. Notably, catalysts derived from calcination at 500 °C exhibited heightened catalytic activity. They advanced the pyrolysis temperature by 135.4 °C and reduced the activation energy by 82.38 kJ/mol compared with pure AP. To further elucidate the decomposition mechanism of AP, the investigation also employed a combined approach involving DSC-TG-FTIR-MS analysis.

3.
Medicine (Baltimore) ; 103(14): e37658, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38579057

RESUMEN

To investigate the status quo and influencing factors of general postpartum well-being in primiparas, analyze its correlation with postpartum depression, and provide a theoretical foundation for enhancing the postpartum well-being of primiparas. From the start of November 2021 to the end of December 2021, the General Information Questionnaire, General Well-Being Scale, and the Edinburgh Postpartum Depression Scale were used to survey primiparas in a tertiary hospital, and the correlation between general well-being and postpartum depression was analyzed. We surveyed a total of 225 primiparas. The average score for general well-being in primiparas was 77.84 ±â€…6.83, and the total score for postpartum depression was 9.11 ±â€…2.51. Confinement location, planned pregnancy, pregnancy complications, neonatal sex, medical expenses, etc, had statistically significant effects on the general well-being scores (P < .05), whereas per capita monthly income, pregnancy complications, maternal and infant care skills, and medical expenses had statistically significant effects on postpartum depression scores (P < .05). Postpartum depression scores were negatively correlated with general well-being, health anxiety, energy, sad or happy mood, relaxation, and tension. There is a negative correlation between the general well-being of primiparas and postpartum depression, suggesting that in clinical care, the focus should be on primiparas with pregnancy complications, and psychological counseling should be provided in advance to prevent postpartum depression and the resulting decrease in well-being.


Asunto(s)
Depresión Posparto , Complicaciones del Embarazo , Embarazo , Lactante , Recién Nacido , Femenino , Humanos , Depresión Posparto/epidemiología , Depresión/epidemiología , Estudios Transversales , Periodo Posparto/psicología , Complicaciones del Embarazo/epidemiología
4.
J Robot Surg ; 18(1): 107, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38436785

RESUMEN

The purpose was to investigate the safety and advantages of different surgical approaches applied to overweight or obese cervical cancer patients by comparing their surgical and oncological outcomes. This is a retrospective cohort study. 382 patients with a body mass index of at least 24.0 kg/m2 and stage IB-IIA (The International Federation of Gynecology and Obstetrics, FIGO 2009) cervical cancer were enrolled, and then were divided into three groups: open radical hysterectomy (ORH) group, laparoscopic radical hysterectomy (LRH) group, and robot-assisted radical hysterectomy (RRH) group according to the surgical approach. IBM SPSS version 25.0 was used to analyze data. There were 51 patients in ORH group, 225 patients in LRH group and 106 patients in RRH group. In the comparison of surgical outcomes, compared to LRH and ORH, RRH had the shortest operating time, the least estimated blood loss, the shortest postoperative hospital stay, and the shortest recovery time for bowel function (P < 0.05). In the comparison of postoperative complications, ORH has the highest rate of postoperative infection and wound complication compared to LRH and RRH (P < 0.05), and RRH has the highest proportion of urinary retention. After a median follow-up time of 61 months, there was no statistically significant difference between the three groups in terms of 5-year overall survival (OS) rate and 5-year recurrence-free survival (RFS) rate, (P = 0.262, P = 0.453). In patients with overweight or obese cervical cancer, the long-term outcomes of the three surgical approaches were comparable, with RRH showing significant advantages over ORH and LRH in terms of surgical outcomes.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Neoplasias del Cuello Uterino , Femenino , Embarazo , Humanos , Sobrepeso , Neoplasias del Cuello Uterino/complicaciones , Neoplasias del Cuello Uterino/cirugía , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/métodos , Obesidad/complicaciones , Complicaciones Posoperatorias/epidemiología
5.
Eur J Obstet Gynecol Reprod Biol ; 294: 210-216, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38301499

RESUMEN

OBJECTIVE: To investigate the relationship between Ki-67 and P16 expression levels after neoadjuvant chemotherapy, and the clinicopathological characteristics and prognosis of patients with locally advanced cervical cancer. METHODS: Patients with FIGO 2009 stage IB2 or IIA2 cervical cancer, who underwent neoadjuvant chemotherapy combined with radical hysterectomy at the First Affiliated Hospital of Chongqing Medical University between January 2015 and December 2019, were identified retrospectively to correlate postoperative Ki-67 and P16 expression levels with clinicopathological factors. The optimal threshold for predicting recurrence was analysed using receiver operating characteristic (ROC) curves for the Ki-67 index, and univariate and multi-factorial Cox regression analysis were used to investigate the association between clinicpathological features including Ki-67 and P16 and recurrence-free survival. RESULTS: In total, 334 patients were included after screening. The cut-off value of Ki-67 for determining recurrence was 67.5 % according to the ROC curve. On multi-factorial Cox analysis, lymphatic vascular space (p = 0.003) and Ki-67 index (p = 0.005) were shown to increase the risk of recurrence, and were independent prognostic factors for recurrence, while the expression of P16 was not significantly associated with the risk of recurrence (p = 0.097, odds ratio = 0.319). Patients with cervical cancer in the high Ki-67 expression group (Ki-67 ≥ 67.5 %) had lower recurrence-free survival and overall survival than patients in the low Ki-67 expression group (Ki-67 < 67.5 %) (p = 0.001 and 0.036, respectively). CONCLUSION: The expression levels of Ki-67 and P16 after neoadjuvant chemotherapy for locally advanced cervical cancer correlated with tumour differentiation. High expression of Ki-67 (Ki-67 ≥ 67.5 %) may indicate poorer recurrence-free survival and overall survival.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Antígeno Ki-67 , Neoplasias del Cuello Uterino/patología , Estudios Retrospectivos , Estadificación de Neoplasias , Pronóstico , Terapia Neoadyuvante , Histerectomía , Recurrencia Local de Neoplasia/patología
6.
Oncol Rep ; 51(3)2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38240107

RESUMEN

Various types of human cancer may develop aberrant trophoblastic differentiation, including histological changes and altered expression of ß­human chorionic gonadotropin (ß­hCG). Aberrant trophoblastic differentiation in epithelial cancer is usually associated with poor differentiation, tumor metastasis, unfavorable prognosis and treatment resistance. Since ß­hCG­targeting vaccines have failed in an early phase II trial, it is crucial to obtain a better understanding of the molecular pathogenesis of trophoblastic differentiation in human cancer. The present review summarizes the clinical and translational research on this topic with the aim of accelerating the development of an effective targeted therapy. Ectopic expression of ß­hCG promotes proliferation, migration, invasion, vasculogenesis and epithelial­mesenchymal transition (EMT) in vitro, and enhances metastatic and tumorigenic capabilities in vivo. Signaling cascades modulated by ß­hCG include the TGF­ß receptor pathway, EMT­related pathways, the c­MET receptor tyrosine kinase and mitogen­activated protein kinase/ERK pathways, and the SMAD2/4 pathway. Taken together, these findings indicated that TGF­ß receptors, c­MET and ERK1/2 are potential therapeutic targets. Nevertheless, further investigation on the molecular basis of aberrant trophoblastic differentiation is mandatory to improve the design of precision therapy for this aggressive type of human cancer.


Asunto(s)
Gonadotropina Coriónica Humana de Subunidad beta , Neoplasias , Humanos , Transducción de Señal , Pronóstico , Sistema de Señalización de MAP Quinasas , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Transición Epitelial-Mesenquimal , Movimiento Celular , Línea Celular Tumoral
7.
Sci Total Environ ; 912: 168918, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38040373

RESUMEN

Accurately applying engineered nanoparticles (NPs) in farmland stress management is important for sustainable agriculture and food safety. We investigated the protective effects of four engineered NPs (SiO2, CeO2, ZnO, and S) on pakchoi under arsenic (As) stress using pot experiments. The results showed that CeO2, SiO2, and S NPs resulted in biomass reduction, while ZnO NPs (100 and 500 mg kg-1) significantly increased shoot height. Although 500 mg kg-1 S NPs rapidly dissolved to release SO42-, reducing soil pH and pore water As content and further reducing shoot As content by 21.6 %, the growth phenotype was inferior to that obtained with 100 mg kg-1 ZnO NPs, probably due to acid damage. The addition of 100 mg kg-1 ZnO NPs not only significantly reduced the total As content in pakchoi by 23.9 % compared to the As-alone treatment but also enhanced plant antioxidative activity by increasing superoxide dismutase (SOD) and peroxidase (POD) activities and decreasing malondialdehyde (MDA) content. ZnO NPs in soil might inhibit As uptake by roots by increasing the dissolved organic carbon (DOC) by 19.12 %. According to the DLVO theory, ZnO NPs were the most effective in preventing As in pore water from entering plant roots due to their smaller hydrated particle size. Redundancy analysis (RDA) further confirmed that DOC and SO42- were the primary factors controlling plant As uptake under the ZnO NP and S NP treatments, respectively. These findings provide an important basis for the safer and more sustainable application of NP-conjugated agrochemicals.


Asunto(s)
Arsénico , Nanopartículas del Metal , Nanopartículas , Nanoestructuras , Contaminantes del Suelo , Óxido de Zinc , Nanoestructuras/toxicidad , Dióxido de Silicio , Suelo/química , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Agua , Óxido de Zinc/química
8.
Oncol Lett ; 26(6): 539, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38020305

RESUMEN

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are the first-line regimen for the treatment of non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, false-negative results are occasionally observed, even with FDA-approved molecular tests. Such examples in have been reported in our pilot study showing a slightly upward-shifted amplification curve using commercial reverse transcription-quantitative (RT-q)PCR. Verification using peptide nucleic acid (PNA) clamping-sequencing, which has a sensitivity of ~0.1%, may allow better prediction of which patients will benefit from EGFR-TKI therapy. To confirm this hypothesis, samples were prospectively collected from 1,783 lung cancer cases diagnosed in National Cheng Kung University Hospital between 2012-2018. An independent lung cancer cohort of 1,944 cases was also recruited from other hospitals. The clinical significance of mutant-enriched PCR with PNA-sequencing was analyzed and patient outcomes were followed. A total of 17 of 34 cases (50%) were found to harbor EGFR mutations by PNA-sequencing. A total of 22 cases were discovered in the independent lung cancer cohort, and 14 of these (63.6%) cases had EGFR mutations. TKIs were administered to 14 of the 17 mutation-positive patients, and a partial response was observed in 4 cases and stable disease in 10 cases. Patients with EGFR mutations receiving a TKI regimen had a longer overall survival (OS) (median: 40.0 vs. 10.0 months) compared with those without treatment. The difference in OS was not significant. Based on the results of the present study, combining RT-qPCR with PNA-sequencing may be a practical supplementary technology in a clinical molecular laboratory for a subset of lung cancer patients in selection of EGFR TKI therapy.

9.
Cell Mol Life Sci ; 80(11): 338, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37897534

RESUMEN

Induction of DNA damage response (DDR) to ensure accurate duplication of genetic information is crucial for maintaining genome integrity during DNA replication. Cellular senescence is a DDR mechanism that prevents the proliferation of cells with damaged DNA to avoid mitotic anomalies and inheritance of the damage over cell generations. Human WWOX gene resides within a common fragile site FRA16D that is preferentially prone to form breaks on metaphase chromosome upon replication stress. We report here that primary Wwox knockout (Wwox-/-) mouse embryonic fibroblasts (MEFs) and WWOX-knockdown human dermal fibroblasts failed to undergo replication-induced cellular senescence after multiple passages in vitro. Strikingly, by greater than 20 passages, accelerated cell cycle progression and increased apoptosis occurred in these late-passage Wwox-/- MEFs. These cells exhibited γH2AX upregulation and microsatellite instability, indicating massive accumulation of nuclear DNA lesions. Ultraviolet radiation-induced premature senescence was also blocked by WWOX knockdown in human HEK293T cells. Mechanistically, overproduction of cytosolic reactive oxygen species caused p16Ink4a promoter hypermethylation, aberrant p53/p21Cip1/Waf1 signaling axis and accelerated p27Kip1 protein degradation, thereby leading to the failure of senescence induction in Wwox-deficient cells after serial passage in culture. We determined that significantly reduced protein stability or loss-of-function A135P/V213G mutations in the DNA-binding domain of p53 caused defective induction of p21Cip1/Waf1 in late-passage Wwox-/- MEFs. Treatment of N-acetyl-L-cysteine prevented downregulation of cyclin-dependent kinase inhibitors and induced senescence in Wwox-/- MEFs. Our findings support an important role for fragile WWOX gene in inducing cellular senescence for maintaining genome integrity during DDR through alleviating oxidative stress.


Asunto(s)
Proteína p53 Supresora de Tumor , Rayos Ultravioleta , Animales , Humanos , Ratones , Senescencia Celular/genética , ADN/metabolismo , Fibroblastos/metabolismo , Inestabilidad Genómica , Células HEK293 , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Oxidorreductasa que Contiene Dominios WW/genética , Oxidorreductasa que Contiene Dominios WW/metabolismo
10.
Org Lett ; 25(20): 3778-3783, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37166360

RESUMEN

Diazoacetates are widely used to synthesize highly valuable indoles. Previous research has focused on using metal carbene reactivity or the innate nucleophilicity of the diazoacetates to create indoles through a traditional two-electron pathway. However, these strategies are constrained by the need for transition metals, oxidants, or substrate prefunctionalization. To overcome the limitations, we report herein an open-shell strategy that utilizes the radical reactivity of diazoacetates to synthesize indoles for the first time, especially for more valuable [a]-annulated indoles. Notably, this visible-light-driven transformation is enabled by a single organophotocatalyst, proceeding without metals ot additives. Preliminary mechanistic studies and density functional theory calculations disclose a relay visible-light photoredox catalytic process that probably involves several discrete photoredox catalytic cycles in a single operation with one organophotocatalyst.

11.
Clin Cardiol ; 46(7): 745-756, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37226575

RESUMEN

BACKGROUND: Whether there is a multiplicative interaction of lactate/albumin (L/A) ratio and geriatric nutritional risk index (GNRI) on the mortality of critically ill elderly patients with heart failure (HF) remains unclear. HYPOTHESIS: To assess the interaction of L/A ratio and GNRI on the all-cause mortality in critically ill elderly patients with HF. METHODS: This was a retrospective cohort study and data were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. The endpoints were 28-day and 1-year all-cause mortality, and the independent variables were L/A ratio and GNRI. The multiplicative interaction of L/A ratio and GNRI on the mortality was examined using Cox proportional-hazards model. RESULTS: A total of 5627 patients were finally included. Results showed that patients with higher L/A ratio or GNRI ≤ 58 had higher risk of 28-day and 1-year all-cause mortality (all p < .01). We also found the significant multiplicative interaction effect between L/A ratio and GNRI score on the 28-day and 1-year all-cause mortality (both p < .05). The increased L/A ratio was associated with higher risk of 28-day and 1-year all-cause mortality in patients with GNRI ≤ 58 than those with GNRI > 58. CONCLUSIONS: There was a multiplicative interaction effect between L/A ratio and GNRI score on the mortality, and low GNRI score was associated with the increased risk of all-cause mortality with the increase of L/A ratio, suggesting the importance of nutrition-oriented intervention in critically ill elderly HF patients with high L/A ratio.


Asunto(s)
Insuficiencia Cardíaca , Evaluación Nutricional , Humanos , Anciano , Estudios de Cohortes , Estudios Retrospectivos , Ácido Láctico , Enfermedad Crítica , Medición de Riesgo/métodos , Insuficiencia Cardíaca/diagnóstico , Albúmina Sérica , Evaluación Geriátrica , Factores de Riesgo
12.
PLoS One ; 18(4): e0284227, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37098015

RESUMEN

Microsatellite instability (MSI) is the primary predictive biomarker for therapeutic efficacies of cancer immunotherapies. Establishment of the MSI detection methods with high sensitivity and accessibility is important. Because MSI is mainly caused by defects in DNA mismatch repair (MMR), immunohistochemical (IHC) staining for the MMR proteins has been widely employed to predict the responses to immunotherapies. Thus, due to the high sensitivity of PCR, the MSI-PCR analysis has also been recommended as the primary approach as MMR IHC. This study aimed to develop a sensitive and convenient platform for daily MSI-PCR services. The routine workflow used a non-labeling QIAxcel capillary electrophoresis system which did not need the fluorescence labeling of the DNA products or usage of a multi-color fluorescence reader. Furthermore, the 15 and 1000 bp size alignment markers were used to precisely detect the size of the DNA product. A cohort of 336 CRC cases was examined by MSI-PCR on the five mononucleotide MSI markers recommended by ESMO. The PCR products were analyzed in the screening gels, followed by high-resolution gel electrophoresis for confirmation if needed. In the MSI-PCR tests, 90.1% (303/336) cases showed clear major shift patterns in the screening gels, and only 33 cases had to be re-examined using the high-resolution gels. The cohort was also analyzed by MMR IHC is, which revealed 98.5% (331/336) concordance with MSI-PCR. In the five discordant cases, 4 (3 MSI-L and 1 MSS) showed MSH6 loss. Besides, one case exhibited MSI-H but no loss in the MMR IHC. Further NGS analysis, in this case, found that missense and frameshift mutations in the PMS2 and MSH6 genes occurred, respectively. In conclusion, the non-labeling MSI-PCR capillary electrophoresis revealed high concordance with the MMR IHC analysis and is cost- and time-effective. Therefore, it shall be highly applicable in clinical laboratories.


Asunto(s)
Neoplasias Colorrectales , Inestabilidad de Microsatélites , Humanos , Reparación de la Incompatibilidad de ADN/genética , Flujo de Trabajo , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Repeticiones de Microsatélite/genética , Proteínas de Unión al ADN/genética , Electroforesis Capilar , Homólogo 1 de la Proteína MutL/genética
13.
Micromachines (Basel) ; 15(1)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38276845

RESUMEN

Typical edge defects in the edge region of a new cemented carbide insert without edge preparation include burrs, poor surface quality, micro-breakages, and irregularities along the edge. To address the problems in new cemented carbide inserts without edge preparations, a chemical-mechanical synergistic preparation (CMSP) method for the cemented carbide insert cutting edge was proposed. Firstly, the CMSP device for the insert cutting edge was constructed. Then, the polishing slurry of the CMSP for the insert cutting edge was optimized using the Taguchi method combined with a grey relation analysis and fuzzy inference. Finally, orthogonal experiments, the Taguchi method, and analysis of variance (ANOVA) were used to investigate the effect of the polishing plate's rotational speed, swing angle, and input frequency of the controller on the edge preparation process, and the parameters were optimized. The results showed that the best parameter combination for the polishing slurry for the cemented carbide inserts was the mass concentration of the abrasive particle of 10 wt%, the mass concentration of the oxidant of 10 wt%, the mass concentration of the dispersant of 2 wt%, and the pH of 8. The CMSP process parameter combination for the linear edge had the polishing plate's rotational speed of 90 rpm, the swing angle of 6°, and the input frequency of the controller of 5000 Hz. The optimum CMSP process parameter combination for the circular edge had the polishing plate's rotational speed of 90 rpm, the swing angle of 6°, and the input frequency of the controller of 7000 Hz. The polishing plate's rotational speed had the most significant impact on the edge preparation process, followed by the swing angle, and the effect of the input frequency of the controller was the smallest. This study demonstrated that CMSP is a potential way to treat the cemented carbide insert cutting edge in a tool enterprise.

14.
Front Oncol ; 12: 1014132, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36568146

RESUMEN

Clonality assessment, which can detect neoplastic T cells by identifying the uniquely recombined T-cell receptor (TCR) genes, provides important support in the diagnosis of T-cell lymphoma (TCL). BIOMED-2 is the gold standard clonality assay and has proven to be effective in European TCL patients. However, we failed to prove its sensitivity in Taiwanese TCL patients, especially based on the TCRß gene. To explore potential impact of genetic background in the BIOMED-2 test, we analyzed TCRß sequences of 21 healthy individuals and two TCL patients. This analysis suggests that genetic variations in the BIOMED-2 primer sites could not explain the difference in sensitivity. The BIOMED-2 test results of the two TCL patients were positive and negative, respectively. Interestingly, a higher percentage (>81%) of non-recombined TCRß sequences was observed in the test-negative patient than those of the test-positive patient and all healthy individuals (13~66%). The result suggests a new TCR target for enhancing TCL diagnosis. To further explore the hypothesis, we proposed a cost-effective digital PCR assay that quantifies the relative abundance of non-recombined TCRß sequences containing a J2-2P~J2-3 segment. With the digital PCR assay, bone marrow specimens from TCL patients (n=9) showed a positive outcome (i.e., the relative abundance of the J2-2P~J2-3 sequences ≧5%), whereas non-TCL patients (n=6) gave a negative result. As five of nine TCL patients had a negative BIOMED-2 test result, the J2-2P~J2-3 sequences may improve TCL detection. This is the first report showing the capability of characterizing non-recombined TCR sequences as a supplementary strategy for the BIOMED-2 clonality test.

16.
Sci Adv ; 8(28): eabn1958, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35857526

RESUMEN

Matching material degradation with host remodeling, including endothelialization and muscular remodeling, is important to vascular regeneration. We fabricated 3D PGS-PCL vascular grafts, which presented tunable polymer components, porosity, mechanical strength, and degrading rate. Furthermore, highly porous structures enabled 3D patterning of conjugated heparin-binding peptide, dimeric thymosin ß4 (DTß4), which played key roles in antiplatelets, fibrinogenesis inhibition, and recruiting circulating progenitor cells, thereafter contributed to high patency rate, and unprecedentedly acquired carotid arterial regeneration in rabbit model. Through single-cell RNA sequencing analysis and cell tracing studies, a subset of endothelial progenitor cells, myeloid-derived CD93+/CD34+ cells, was identified as the main contributor to final endothelium regeneration. To conclude, DTß4-inspired porous 3DVGs present adjustable physical properties, superior anticoagulating, and re-endothelializing potentials, which leads to the regeneration of small-caliber artery, thus offering a promising tool for vessel replacement in clinical applications.


Asunto(s)
Injerto Vascular , Animales , Prótesis Vascular , Endotelio Vascular/fisiología , Polímeros , Porosidad , Conejos
17.
Adv Mater ; 34(31): e2200004, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35688799

RESUMEN

Transition metal dichalcogenide (TMD) quantum dots (QDs) with defects have attracted interesting chemistry due to the contribution of vacancies to their unique optical, physical, catalytic, and electrical properties. Engineering defined defects into molybdenum sulfide (MoS2 ) QDs is challenging. Herein, by applying a mild biomineralization-assisted bottom-up strategy, blue photoluminescent MoS2 QDs (B-QDs) with a high density of defects are fabricated. The two-stage synthesis begins with a bottom-up synthesis of original MoS2 QDs (O-QDs) through chemical reactions of Mo and sulfide ions, followed by alkaline etching that creates high sulfur-vacancy defects to eventually form B-QDs. Alkaline etching significantly increases the photoluminescence (PL) and photo-oxidation. An increase in defect density is shown to bring about increased active sites and decreased bandgap energy; which is further validated with density functional theory calculations. There is strengthened binding affinity between QDs and O2 due to lower gap energy (∆EST ) between S1 and T1 , accompanied with improved intersystem crossing (ISC) efficiency. Lowered gap energy contributes to assist e- -h+ pair formation and the strengthened binding affinity between QDs and 3 O2 . Defect engineering unravels another dimension of material properties control and can bring fresh new applications to otherwise well characterized TMD nanomaterials.

18.
Front Plant Sci ; 13: 814870, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35498668

RESUMEN

The pollen intine layer is necessary for male fertility in flowering plants. However, the mechanisms behind the developmental regulation of intine formation still remain largely unknown. Here, we identified a positive regulator, Arabidopsis novel microgametophyte defective mutant 1 (AtNMDM1), which influences male fertility by regulating intine formation. The AtNMDM1, encoding a pollen nuclei-localized protein, was highly expressed in the pollens at the late anther stages, 10-12. Both the mutations and the knock-down of AtNMDM1 resulted in pollen defects and significantly lowered the seed-setting rates. Genetic transmission analysis indicated that AtNMDM1 is a microgametophyte lethal gene. Calcofluor white staining revealed that abnormal cellulose distribution was present in the aborted pollen. Ultrastructural analyses showed that the abnormal intine rather than the exine led to pollen abortion. We further found, using transcriptome analysis, that cell wall modification was the most highly enriched gene ontology (GO) term used in the category of biological processes. Notably, two categories of genes, Arabinogalactan proteins (AGPs) and pectin methylesterases (PMEs) were greatly reduced, which were associated with pollen intine formation. In addition, we also identified another regulator, AtNMDM2, which interacted with AtNMDM1 in the pollen nuclei. Taken together, we identified a novel regulator, AtNMDM1 that affected cellulose distribution in the intine by regulating intine-related gene expression; furthermore, these results provide insights into the molecular mechanisms of pollen intine development.

19.
Biomacromolecules ; 23(4): 1757-1764, 2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-35293717

RESUMEN

Polysarcosine (PSar), a water-soluble polypeptoid, is gifted with biodegradability via the random ring-opening copolymerization of sarcosine- and alanine-N-thiocarboxyanhydrides catalyzed by acetic acid in controlled manners. Kinetic investigation reveals the copolymerization behavior of the two monomers. The random copolymers, named PaS, with high molecular weights between 5.3 and 43.6 kg/mol and tunable Ala molar fractions varying from 6 to 43% can be degraded by porcine pancreatic elastase within 50 days under mild conditions (pH = 8.0 at 37 °C). Both the biodegradation rate and water solubility of PaS depend on the content of Ala residues. PaS with Ala fractions below 43% are soluble in water, while the one with 43% Ala self-assembles in water into nanoparticles. Moreover, PaS are noncytotoxic at the concentration of 5 mg/mL. The biodegradability and biocompatibility endow the Ala-containing PSar with the potential to replace poly(ethylene glycol) as a protective shield in drug-delivery.


Asunto(s)
Alanina , Sarcosina , Animales , Péptidos/química , Polietilenglicoles , Sarcosina/análogos & derivados , Sarcosina/química , Porcinos , Agua
20.
Sci Rep ; 12(1): 3319, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35228655

RESUMEN

Neoadjuvant immunotherapy and chemotherapy have improved the major pathological response (MPR) in patients with early-stage operable non-small cell lung cancer (NSCLC). This study aimed to assess whether the presence of targetable driver mutations affects the efficacy of the combination of immunotherapy and chemotherapy. We enrolled patients with early-stage operable NSCLC who received preoperative neoadjuvant therapy between January 1, 2017, and December 30, 2020. Neoadjuvant therapy was delivered with platinum-doublet chemotherapy; moreover, pembrolizumab was added at the attending physician's discretion based on patient's request. Pathological responses were assessed; moreover, disease-free survival was estimated. Next-generation sequencing was performed in case sufficient preoperative biopsy specimens were obtained. We included 23 patients; among them, 11 received a combination of neoadjuvant immunotherapy and chemotherapy while 12 received neoadjuvant chemotherapy alone. The MPR and pathological complete response rates were 54.5% and 27.3%, respectively, in patients who received a combination of neoadjuvant immunotherapy and chemotherapy. These rates were significantly higher than those in patients who only received neoadjuvant chemotherapy. Three patients in the combination group experienced disease recurrence during the follow-up period even though two of them showed an MPR. These three patients had targetable driver mutations, including an EGFR exon 20 insertion, EGFR exon 21 L858R substitution, and MET exon 14 skipping. Only one patient who remained disease-free had a targetable driver mutation. Among patients with early-stage operable NSCLC requiring neoadjuvant therapy, comprehensive genomic profiling is crucial before the administration of the combination of neoadjuvant immunotherapy and chemotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/uso terapéutico , Humanos , Inmunoterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Resultado del Tratamiento
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