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1.
IUBMB Life ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39139071

RESUMO

Senescent cells are typically characterized by a stable proliferation arrested in dividing cells accompanied with a senescence-associated secretory phenotype (SASP). Skin cellular senescence is the primary cause of skin aging, whereas the lack of identified skin senescence markers limits our understanding of the mechanisms involved in skin aging. Recent studies have revealed that intracellular calcium signaling has emerged as a key player in regulating cellular senescence and aging. However, the implication and roles of calcium signaling in skin keratinocyte senescence remain only partially understood. In this study, we developed a model for skin keratinocyte senescence using ionizing radiation (I/R) stimulation and found that the calcium-associated gene transglutaminase 2 (TGM2) was significantly induced compared with normal control. Interestingly, inhibition of TGM2 was found to delay skin keratinocyte senescence by suppressing I/R-promoted intracellular calcium signaling, accumulation of reactive oxygen species (ROS), DNA damage, as well as NF-κB-mediated SASP secretion. Taken together, our findings demonstrate that inhibition of TGM2 contributes to bypassing I/R-induced skin keratinocyte senescence and sheds light on novel strategies against skin stresses caused by I/R.

2.
Front Surg ; 11: 1348806, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055132

RESUMO

Objective: To study the effectiveness of liver transplantation (LT) in treating mitochondrial DNA depletion syndrome (MDS) caused by the MPV17 gene variant. Case presentation: A boy aged 2.8 years presented with edema of the lower limbs and abdomen, which persisted for over 10 days and was of unknown origin; this was accompanied by abnormal liver function, intractable hypoglycemia, and hyperlactatemia. During the second week of onset, he developed acute-on-chronic liver failure and was diagnosed with MDS due to homozygous variant c.293C>T in the MPV17 gene. Subsequently, he underwent LT from a cadaveric donor. At follow-up after 15 months, his liver function was found to be normal, without any symptoms. Additionally, a literature review was performed that included MDS patients with the MPV17 variant who underwent LT. The results demonstrated that the survival rates for MDS patients who underwent LT were 69.5%, 38.6%, 38.6%, and 38.6% at 1-year, 5-year, 10-year, and 20-year intervals, respectively. Sub-group analyses revealed the survival rate of MDS patients with isolated liver disease (83.33%, 5/6) was higher than that of hepatocerebral MDS patients (44.44%, 8/18). Fifteen variants were identified in the MPV17 gene, and patients with the c.293C>T (p.P98l) variant exhibited the highest survival rate. Conclusion: Hepatocerebral MDS patients without neurological symptoms may benefit from LT.

3.
Adv Mater ; 36(32): e2405731, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38857110

RESUMO

The recycling and utilization of precious metals have emerged as a critical research focus in advancing the development of the circular economy. Among numerous methods for recovering precious metals such as gold, adsorbents with both high adsorption selectivity and capacity have become key technologies. This article incorporated the N-phenylpyrrolidine into a flexible porous polynorbornene backbone to create a class of distinctive porous organic polymers, named BIT-POP-14-BIT-POP-17. Through a reductive capture mechanism, the reductive adsorption sites of N-phenylpyrrolidine coordinate selectively with precious metals, the reduced metal is captured by the hierarchically porous polymers with flexible backbone. This approach leads to remarkable gold recovery efficiency, achieving a record of 2321 mg g-1 at ambient conditions, and 3020 mg g-1 under UV light, surpassing the theoretical limit. The porous polymers are filled in a column for a continuous uptake of gold from waste printed circuit boards (PCBs), showing recovery efficiency toward gold as high as 95% after 84 h. Overall, this work offers a new perspective on designing novel adsorbents for precious metal recovery, providing inspiration for researchers to explore novel adsorption modes and contribute to the advancement of the circular economy.

4.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345452

RESUMO

Numerous scientific satellites require micronewton thrusters for compensating environmental disturbances. The mass flow control proportional valve plays a crucial role in precisely regulating the thrust. To meet the high resolution and wide range requirements of the thrusters, this paper introduces a novel proportional valve with two sets of independently controllable piezoelectric stack. One set of the piezo-stack is used to compensate the stroke loss of the valve core, mainly caused by the deformation of the valve seat. The valve sealing mechanism is carefully analyzed to reduce the stroke loss. Another set of the stack works as the primary actuator, enabling the high mass flow control resolution. Two sets of independently controlled piezoelectric stacks not only expand the range and improve the range ratio but also provide redundancy and enhance reliability. This means that the actuator can still operate at lower ranges even if one piezo-stack is damaged. The piezo-actuators are assembled using U-shaped connectors, creating a compact and space-efficient overall design. Experimental tests have been conducted to verify the performance of the valve, which demonstrated a mass flow range of 0-675 µg/s with a resolution better than 0.1 µg/s and a flow noise below 0.1 µg/s/Hz1/2 at 0.1 mHz-1 Hz.

5.
Front Cell Infect Microbiol ; 13: 1175747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465762

RESUMO

Objective: The aim of this study was to explore the predictive value of the ratio of procalcitonin (PCT) in serum to Simpson's dominance index (SDI) in bronchoalveolar lavage fluid (BALF), in short-term prognosis of patients with severe bacterial pneumonia (SBP). Methods: This is a retrospective review of case materials of 110 patients with SBP who selected BALF metagenomic next-generation sequencing technique in the intensive care unit (ICU) of the Affiliated Hospital of Yangzhou University from January 2019 and July 2022. Based on the acute physiology and chronic health status score II, within 24 h after admission to the ICU, patients were divided into a non-critical group (n = 40) and a critical group (n = 70). Taking death caused by bacterial pneumonia as the endpoint event, the 28-day prognosis was recorded, and the patients were divided into a survival group (n = 76) and a death group (n = 34). The SDI, PCT, C-reactive protein (CRP), PCT/SDI, and CRP/SDI were compared and analyzed. Results: Compared with the non-critical group, the critical group had a higher PCT level, a greater PCT/SDI ratio, a longer ventilator-assisted ventilation time (VAVT), and more deaths in 28 days. Compared with the survivors, the death group had a higher PCT level, a lower SDI level, and a greater PCT/SDI ratio. The SDI level was significantly negatively correlated with the VAVT (r = -0.675, p < 0.05), while the PCT level, ratio of PCT/SDI, and ratio of CRP/SDI were remarkably positively correlated with VAVT (r = 0.669, 0.749, and 0.718, respectively, p < 0.05). The receiver operating characteristic (ROC) curves analysis showed that the area under ROC curves of PCT/SDI predicting patient death within 28 days was 0.851, followed by PCT + SDI, PCT, SDI, and CRP/SDI (0.845, 0.811, 0.778, and 0.720, respectively). The sensitivity and specificity of PCT/SDI for predicting death were 94.1% and 65.8%, respectively, at the optimal value (11.56). Cox regression analysis displayed that PCT/SDI (HR = 1.562; 95% CI: 1.271 to 1.920; p = 0.039) and PCT (HR = 1.148; 95% CI: 1.105 to 1.314; p = 0.015) were independent predictors of death in patients. Conclusion: The ratio of PCT/SDI was a more valuable marker in predicting the 28-day prognosis in patients with SBP.


Assuntos
Pneumonia Bacteriana , Sepse , Humanos , Pró-Calcitonina , Sepse/metabolismo , Sensibilidade e Especificidade , Estudos Retrospectivos , Proteína C-Reativa , Pneumonia Bacteriana/diagnóstico
6.
Cancer Med ; 12(13): 14025-14036, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37329224

RESUMO

BACKGROUND: Although thymic squamous cell carcinoma (TSCC) is among the most prevalent forms of thymic carcinoma, there are relatively few studies on this tumor type, and its staging, optimal treatment strategies, and relevant prognostic factors remain controversial. METHODS: The present study analyzed 79 patients diagnosed with TSCC between January 2008 and January 2021. Kaplan-Meier curves and Cox univariate and multivariate regression analyses were used to explore factors associated with overall survival (OS) and progression-free survival (PFS) in the overall patient cohort and patient subgroups stratified according to the TNM stage. Time-dependent receiver operating characteristic (ROC) analyses were used to compare the TNM and Masaoka systems as predictors of patient prognosis. RESULTS: The 5- and 10-year OS rates in this study were 65.5% and 49.4%, respectively, with corresponding 5- and 10-year PFS rates of 52.3% and 37.9%. Survival outcomes were better for patients with early-stage disease (p < 0.001) and patients that underwent surgical treatment (p < 0.001). Neither extent of resection (p = 0.820) nor the surgical approach (p = 0.444) influenced patient survival. In individuals with advanced disease, all forms of adjuvant therapy including radiotherapy (p = 0.021), chemotherapy (p = 0.035), and chemoradiation (p = 0.01) significantly improved patient PFS, but only adjuvant chemoradiotherapy improved patient OS (p = 0.035). When predicting the patient survival outcomes, the TNM system was slightly superior to the Masaoka system (area under the ROC curve [AUC] at 5 years: OS, 0.742 vs. 0.723; PFS, 0.846 vs. 0.816). CONCLUSION: TSCC is an orphan malignancy with a poor prognosis. TNM staging may be superior to Masaoka staging as a predictor of TSCC patient prognosis. Surgery is the mainstay of TSCC treatment. Video-assisted thoracoscopy (VATS) should be considered for selected patients. Multimodal therapy was associated with excellent results for patients with advanced TNM stage, particularly when surgery was accompanied by adjuvant chemoradiation.


Assuntos
Carcinoma de Células Escamosas , Timoma , Neoplasias do Timo , Humanos , Prognóstico , Timoma/patologia , Carcinoma de Células Escamosas/patologia , Estadiamento de Neoplasias , Neoplasias do Timo/patologia , Estudos Retrospectivos
7.
Front Aging Neurosci ; 15: 1167170, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205058

RESUMO

For post-menopausal women, stroke is complicated by the variable effects of estrogen therapy and the age-related therapeutic consequences involved. Estrogen therapy has been shown to have an age-dimorphic effect, which is neuroprotective in young females, but non-neuroprotective, even neurotoxic in acyclic females. We hypothesized that arterial baroreflex (ABR) and its downstream acetylcholine-α7 nicotinic acetylcholine receptor (α7nAChR) anti-inflammatory pathways are involved in estrogen efficacy toward cerebral ischemic damage. Our data showed that estrogen supplements contributed to ABR improvement and neuroprotection in adult, not aged, ovariectomized (OVX) rats. In adult rats, OVX-induced estrogen deficiency aggravated middle cerebral artery occlusion (MCAO), which induced brain infarction and reduced ABR function, with decreased α7nAChR expression of the brain and exaggerated inflammation following MCAO; these effects were significantly prevented by supplementation with estrogen. ABR impairment by sinoaortic denervation partly attenuated the estrogen effect on baroreflex sensitivity (BRS) and ischemic damage in adult rats, as well as α7nAChR expression and inflammatory response. These data suggested that ABR and acetylcholine-α7nAChR anti-inflammatory pathways are involved in the neuroprotection of estrogen in adult OVX rats. In contrast, aged rats exhibited more severe ischemic damage and inflammatory response than adult rats, as well as poorer baroreflex function and lower α7nAChR expression. Estrogen supplements did not improve BRS or confer neuroprotection in aged rats without affecting brain α7nAChR and post-ischemic inflammation. Most importantly, ketanserin restored ABR function and significantly postponed the onset of stroke in aged female strokeprone spontaneously hypertensive rats, whereas estrogen treatment failed to delay the development of stroke. Our findings reveal that estrogen is protective against ischemic stroke (IS) in adult female rats and that ABR played a role in this beneficial action. Dysfunction of ABR and unresponsiveness to estrogen in aged female rats may contribute to a reduced estrogen efficacy against cerebral ischemia.

8.
Angew Chem Int Ed Engl ; 62(18): e202301059, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36815280

RESUMO

Adjuvants stimulate the immune system to vigorously respond to a vaccine. While current adjuvants such as aluminum salts and oil-in-water emulsions have been used for decades, they do not generate broad and long-lasting responses in many vaccines. Consequently, more potent adjuvants are needed. Here, using computer-aided molecule design and machine learning, we discovered 2 new, broad-spectrum adjuvants that can boost vaccine responses. Our library containing 46 toll-like receptor (TLR)-targeting agonist ligands were assembled on Au nanoparticles. Comprehensive in vitro, ex vivo and in vivo studies showed both leads promoted dendritic cell activation via multiple TLRs and enhanced antigen presentation to T cells. When used together with tumor-specific antigens to immunize mice against B16-OVA melanoma and 4T1-PD1 breast cancer, both adjuvants unleashed strong immune responses that suppressed tumor growth and lung metastases. Our results show computer-aided design and screening can rapidly uncover potent adjuvants for tackling waning immunity in current vaccines.


Assuntos
Nanopartículas Metálicas , Neoplasias , Vacinas , Animais , Camundongos , Adjuvantes de Vacinas , Ouro , Adjuvantes Imunológicos/farmacologia , Antígenos de Neoplasias
9.
J Am Chem Soc ; 145(4): 2252-2263, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36657461

RESUMO

It is highly desirable to fabricate an accessible catalyst surface that can efficiently activate reactants and desorb products to promote the local surface reaction equilibrium in heterogeneous catalysis. Herein, rare-earth oxycarbonates (Ln2O2CO3, where Ln = La and Sm), which have molecular-exchangeable (H2O and CO2) surface structures according to the ordered layered arrangement of Ln2O22+ and CO32- ions, are unearthed. On this basis, a series of Ln2O2CO3-supported Cu catalysts are prepared through the deposition precipitation method, which provides excellent catalytic activity and stability for the water-gas shift (WGS) reaction. Density functional theory calculations combined with systematic experimental characterizations verify that H2O spontaneously dissociates on the surface of Ln2O2CO3 to form hydroxyl by eliminating the carbonate through the release of CO2. This interchange efficiently promotes the WGS reaction equilibrium shift on the local surface and prevents the carbonate accumulation from hindering the active sites. The discovery of the unique layered structure provides a so-called "self-cleaning" active surface for the WGS reaction and opens new perspectives about the application of rare-earth oxycarbonate nanomaterials in C1 chemistry.

10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(5): 809-814, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36325778

RESUMO

Objective To investigate the clinical characteristics of 30-day unplanned reoperations after thoracic surgery. Methods We retrospectively analyzed the clinical data of patients with unplanned reoperations within 30 days after thoracic surgery in Peking Union Medical College Hospital from May 2016 to May 2021. Results The 30-day unplanned reoperations showed the incidence of 0.75%(79/10 543),the median hospital stay of 19(12,37) days,and the median hospitalization cost of 109 929.11(80 549.46,173 491.87) yuan.Twenty-two(27.85%) patients received blood transfusion and 26(32.91%) underwent intensive care.The period between May 2016 and May 2017 witnessed the most unplanned reoperations.The main causes of unplanned reoperations after thoracic surgery were bleeding(21.52%),chylothorax(17.72%),pulmonary air leakage(16.46%),atelectasis(13.92%),and gastroesophageal fistula(11.39%).Specifically,the main causes of unplanned reoperations in the patients of non-esophagus/cardia group were bleeding,pulmonary air leakage,atelectasis,and chylothorax,and those in the patients of esophagus/cardia group were gastroesophageal fistula,incision infection and poor healing,bleeding,and chylothorax.Among all the patients with unplanned reoperations,4 patients died,17 improved,and 58 recovered. Conclusions The patients who underwent unplanned reoperations after thoracic surgery had a long hospital stay and high hospitalization costs. Bleeding,chylothorax,pulmonary air leakage,atelectasis,and gastroesophageal fistula were the main reasons for the unplanned reoperations.


Assuntos
Quilotórax , Atelectasia Pulmonar , Cirurgia Torácica , Humanos , Reoperação , Estudos Retrospectivos , Quilotórax/cirurgia , Hemorragia , Atelectasia Pulmonar/cirurgia , Complicações Pós-Operatórias/epidemiologia
11.
Expert Rev Anticancer Ther ; 22(12): 1349-1355, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36373901

RESUMO

OBJECTIVES: The present study explores an extremely rare disease, thymic mucosa-associated lymphoid tissue (MALT) lymphoma, for its characteristics and prognostic factors by analyzing the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: From 2000 to 2018, cases with a diagnosed thymic MALT lymphoma were extracted. Clinical characteristics, treatments, and survival patterns of these cases were analyzed. RESULTS: Thymic MALT lymphoma (n = 26) accounted for 0.09% of all MALT lymphomas. With a sex ratio of 0.53 (male/female), 68% white population was affected. Most cases were diagnosed with Ann Arbor stage I (50%), yet advanced-stage did not show worse prognosis (p = 0.236). Different treatment protocols did not influence the overall prognosis (p > 0.99). The 5- and 10- year overall survival rates were 83.1% and 78.2%, respectively. Older than 70 years may be an independent risk factor for overall survival (HR = 7.166 [95% CI 1.173-43.756], p = 0.033). CONCLUSION: Thymic MALT lymphoma is a highly rare disease with a favorable prognosis. Ann Arbor staging might not be appropriate to classify severity of this disease or its treatment. Older people may have worse survival. A standardized treatment mode needs to be established, and surgery could remain as the mainstay.


Assuntos
Linfoma de Zona Marginal Tipo Células B , Feminino , Humanos , Masculino , Idoso , Linfoma de Zona Marginal Tipo Células B/terapia , Doenças Raras
12.
J Thorac Dis ; 14(8): 2894-2907, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36071772

RESUMO

Background: Mucosa-associated lymphoid tissue (MALT) lymphoma of the thymus is a rare disease. The present meta-analysis aims at accumulating current evidence to explore the clinical characteristics, treatments, and prognoses of thymic MALT lymphoma. Methods: We searched seven databases for studies published between the start date of database establishment and September 15, 2021. We included studies of patients with histological diagnoses and excluded those without data specifically on thymic MALT lymphoma. The quality was analyzed using an assessment tool. All data were tabulated. Pooled proportion was obtained using random-effects model. Statistical analysis was performed on R statistic software. Results: Overall, 52 case reports and 13 case series were eligible. The quality of case reports was inferior to that of case series in terms of selection (P<0.001). Based on the analysis of patients in the case reports, age, gender, concurrent diseases, and tumor size did not differ between limited-stage and advanced-stage cases. Surgery is the mainstay to treat thymic MALT lymphoma. The surgical approach and extent did not influence the occurrence of events. Patients at Ann Arbor stage I were prone to not receiving postoperative therapy (P=0.011), though it may not reduce the occurrence of events (P=0.637). The five-year overall survival (OS) rate and five-year progression-free survival (PFS) rate were 97.2% and 88.4%, respectively. Patients with advanced-stage disease were more likely to suffer events (P=0.009). Conclusions: Thymic MALT lymphoma is an extremely rare disease with a favorable prognosis. Currently available evidence is insufficient to draw solid judgments about treatment and prognosis. However, patients may benefit if thymectomy is chosen as the primary treatment. In some patients, lymph node sampling or dissection should be considered. In addition, if the patient is at an advanced-stage, postoperative therapy should be considered.

13.
J Invest Surg ; 35(10): 1747-1753, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35914896

RESUMO

Background. Ectopic mediastinal parathyroid glands are parathyroid glands located completely below the clavicle. At present, most literature reports on ectopic mediastinal parathyroid tumors (EMPT) are case reports or small case sequences.Methods. This study conducted a retrospective analysis of ectopic mediastinal parathyroid tumors cases treated over the past 23 years, summarizing and analyzing general conditions, preoperative positioning, postoperative pathology, intraoperative conditions, and long-term follow-up results.Results. This study enrolled 28 patients. Among them, 27 patients underwent preoperative localization diagnosis using 99mTc-sestamibi scan (MIBI) in conjunction with chest computed tomography (CT), including 26 cases of the anterior superior mediastinum and 2 cases of middle mediastinum. Postoperative pathology revealed 23 cases of parathyroid adenoma, 4 cases of parathyroid hyperplasia, and 1 case of parathyroid cyst. In this study, 12 patients underwent video-assisted thoracoscopic surgery (VATS) and thoracotomy approaches. Using Mann-Whitney U test, we discovered that VATS approach group is significantly superior in surgical time (P = 0.039) and intraoperative bleeding (P < 0.001). Within one week of surgery, 26 patients with primary hyperparathyroidism (PHPT) experienced a significant decrease in blood parathyroid hormone (PTH) (P < 0.001) and blood calcium (P < 0.001), and all achieved long-term remission.Conclusions. EMPT is most frequently performed in the anterior superior mediastinum. EMPT is predominantly parathyroid tumors, and most of them are associated with PHPT. MIBI and chest CT combination can be used for preoperative lesion localization (positive rate 96.15%). VATS can be used as a better surgical approach. PHPT patients before surgery can achieve long-term symptom relief with surgical treatment.


Assuntos
Adenoma , Neoplasias das Paratireoides , Adenoma/diagnóstico , Adenoma/patologia , Adenoma/cirurgia , Cálcio , Humanos , Mediastino/diagnóstico por imagem , Mediastino/patologia , Mediastino/cirurgia , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/patologia , Glândulas Paratireoides/cirurgia , Hormônio Paratireóideo , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/cirurgia , Estudos Retrospectivos , Tecnécio Tc 99m Sestamibi
14.
Artigo em Inglês | MEDLINE | ID: mdl-35820061

RESUMO

Highly selective separation and purification of acetylene (C2H2) from ethylene (C2H4) and carbon dioxide (CO2) are daunting challenges in light of their similar molecule sizes and physical properties. Herein, we report a two-dimensional (2D) stable metal-organic framework (MOF), NUM-11 ([Cu(Hmpba)2]·1.5DMF) (H2mpba = 4-(3,5-dimethyl-1H-pyrazol-4-yl)benzoic acid), with sql topology, stacked together through π-π interactions for efficient separation of C2H2 from C2H4 and CO2. The 2D-MOF material offers high hydrolytic stability and good purification capacity; especially, it could survive in water for 7 months, even longer. This stable MOF selectively captures C2H2 from mixtures containing C2H4 and CO2, as determined by adsorption isotherms. The ideal adsorbed solution theory selectivity calculations and transient breakthrough experiments were performed to verify the separation capacity. The low isosteric heat of NUM-11a (desolvated NUM-11) (18.24 kJ mol-1 for C2H2) validates the feasibility of adsorbent regeneration with low energy footprint consumption. Furthermore, Grand Canonical Monte Carlo simulations confirmed that the pore surface of the NUM-11 framework enabled preferential binding of C2H2 over C2H4 and CO2 via multiple C-H···O, C-H···π, and C-H···C interactions. This work provides some insights to prepare stable MOF materials toward the purification of C2H2, and the water-stable structure, low isosteric heat, and good cycling stability of NUM-11 make it very promising for practical industrial application.

15.
Nat Commun ; 13(1): 2443, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508459

RESUMO

The metal-support interfaces between metals and oxide supports have long been studied in catalytic applications, thanks to their significance in structural stability and efficient catalytic activity. The metal-rare earth oxide interface is particularly interesting because these early transition cations have high electrophilicity, and therefore good binding strength with Lewis basic molecules, such as H2O. Based on this feature, here we design a highly efficient composite Ni-Y2O3 catalyst, which forms abundant active Ni-NiOx-Y2O3 interfaces under the water-gas shift (WGS) reaction condition, achieving 140.6 µmolCO gcat-1 s-1 rate at 300 °C, which is the highest activity for Ni-based catalysts. A combination of theory and ex/in situ experimental study suggests that Y2O3 helps H2O dissociation at the Ni-NiOx-Y2O3 interfaces, promoting this rate limiting step in the WGS reaction. Construction of such new interfacial structure for molecules activation holds great promise in many catalytic systems.

16.
ChemSusChem ; 15(13): e202200392, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35373919

RESUMO

5-Hydroxymethylfurfural (HMF) containing C=O, C-O, and furan ring functional groups is an important platform chemical derived from C6 sugars. The selective hydrogenation of C=O in HMF produces 2,5-dihydroxymethylfuran (DHMF), which is a potential sustainable substitute for petroleum-based building blocks. Here, 2,5-furandicarboxylic acid (H2 FDC), a promising sustainable alternative to terephthalic acid, was employed as a renewable ligand to synthesize a novel Cu metal-organic framework (Cu-FDC). With a polyvinyl pyrrolidone (PVP)-assisted approach, 2D Cu-FDC nano-lamellae of micrometer lateral dimensions and nanometer thickness could be obtained, which could be used as a precursor to fabricate 2D oxygen-rich carbon nanosheets embedded with Cu nanoparticles (denoted CFP-300) after a thermal treatment at 300 °C under N2 atmosphere. The synthesized CFP-300 exhibited excellent catalytic performance and stability for the selective hydrogenation of HMF to DHMF. These results demonstrated a sustainable route to synthesize efficient catalysts by employing metal-organic frameworks based on renewable ligands.


Assuntos
Furaldeído , Povidona , Furaldeído/análogos & derivados , Hidrogenação , Ligantes
17.
Sci Total Environ ; 835: 155404, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35469890

RESUMO

It is important to ensure food safety to study the technology and mechanism of pesticide residues degradation in crops. Though γ-aminobutyric acid (GABA) has been widely reported to involve in plant stress resistance, whether exogenous application or endogenous regulation of GABA by gene-editing technology can promote the pesticide detoxification is not clear in plants. Using tomato and chlorothalonil (CHT) as research models, we discovered that exogenous application of GABA or endogenous elevation of GABA by knockout of pyruvate-dependent GABA transaminase promoted both CHT metabolism and plant stress tolerance to CHT. This is closely related to the active adaptation of GABA to CHT stress by regulating the plant GABA shunt pathway and polyamine pathway. The transcriptome data revealed 17 target genes that may be closely related to the involvement of GABA in CHT metabolism, including 4 peroxidases, 5 glycosyltransferases, 4 glutathione S-transferases, and 4 ABC transporters. In addition, the glutathione detoxification pathway and antioxidative enzyme also actively participated in the GABA-induced CHT detoxification process, which played an important role in relieving CHT stress. As a result, GABA significantly increased the photosynthetic capacity of tomato leaves under CHT stress. While studying photosynthesis, we unexpectedly found that GABA promotes stomatal closure in terms of decreased stomatal conductance and stomatal diameter. This result implies that GABA can reduce CHT absorption by regulating stomatal movement in leaves. Together, we provided a novel viewpoint that foliar application of GABA or metabolic engineering of GABA is an effective approach to reduce the risk of pesticide contamination in crop production.


Assuntos
Praguicidas , Solanum lycopersicum , Glutationa/metabolismo , Solanum lycopersicum/metabolismo , Praguicidas/metabolismo , Folhas de Planta/metabolismo , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologia
18.
Nat Commun ; 13(1): 867, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35165303

RESUMO

For high-temperature catalytic reaction, it is of significant importance and challenge to construct stable active sites in catalysts. Herein, we report the construction of sufficient and stable copper clusters in the copper‒ceria catalyst with high Cu loading (15 wt.%) for the high-temperature reverse water gas shift (RWGS) reaction. Under very harsh working conditions, the ceria nanorods suffered a partial sintering, on which the 2D and 3D copper clusters were formed. This partially sintered catalyst exhibits unmatched activity and excellent durability at high temperature. The interaction between the copper and ceria ensures the copper clusters stably anchored on the surface of ceria. Abundant in situ generated and consumed surface oxygen vacancies form synergistic effect with adjacent copper clusters to promote the reaction process. This work investigates the structure-function relation of the catalyst with sintered and inhomogeneous structure and explores the potential application of the sintered catalyst in C1 chemistry.

19.
Inorg Chem ; 60(24): 19328-19335, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34865466

RESUMO

Ethylene (C2H4) is one of the most significant substances in the petrochemical industry; however, the capture of acetylene (C2H2) in about 1% from C2H2/C2H4 mixtures is a difficult task because of the similarity of their physical properties. With the aggravation of the energy crisis, using metal-organic framework (MOF) materials to purify C2H4 through adsorptive separation is a promising way to save energy and reduce emission. Pore-space partition (PSP) with the aim of enhancing the density of the binding sites and the strength of the host-guest interactions is an effective means to promote a solution for the challenging gas separation problems. Herein, we report a new embedding metal-carboxylate chain-induced topology upgrade strategy within a MOF to realize PSP and separation of C2H2/C2H4 mixtures. As a proof of concept, we construct a microporous MOF (NUM-12) utilizing the in situ insertion of cobalt terephthalic chains into a pretargeted ant-type framework during synthesis. Because of the attainment of an elaborately tuned aperture size and a specific pore environment through this strategy, NUM-12a (activated NUM-12) not only has a remarkable gas sorption capacity and strong interactions for C2H2 but also possesses an excellent purification performance for C2H2/C2H4 mixtures. Both experiments and simulation calculations clearly reveal that NUM-12 is a promising candidate for the separation of C2H2/C2H4, proving the feasibility of this new strategy for developing newly fashioned MOFs with adjustable structure and performance.

20.
World J Clin Cases ; 9(26): 7876-7885, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34621841

RESUMO

BACKGROUND: The ATP6AP1 gene coding for the accessory protein Ac45 of the vacuolar-type adenosine triphosphatases (V-ATPase) is located on chromosome Xq28. Defects in certain subunits or accessory subunits of the V-ATPase can lead to congenital disorders of glycosylation (CDG). CDG is a group of metabolic disorders in which defective protein and lipid glycosylation processes affect multiple tissues and organs. Therefore, the clinical presentation of patients with ATP6AP1-CDG varies widely. In this report, we present a case of ATP6AP1-CDG in a Chinese infant, with clinical features and genotype. CASE SUMMARY: An 8-mo-old boy was admitted to our hospital because unexplained hepatosplenomegaly and elevated transaminases that had been noted while he was being treated for a cough at a local hospital. A post-admission examination at our hospital revealed abnormalities in the infant's liver, brain, and immune system. Trio-based whole exome gene analysis identified a hemizygous pathogenic mutation c.1036G>A (p.E346K) in exon 9 of the ATP6AP1 gene. This variant of the ATP6AP1 gene has not been reported in East Asian countries until now. CONCLUSION: Based on the infant's clinical manifestations and the results of genetic detection, he was clearly diagnosed with ATP6AP1-CDG. The clinical manifestations of children with CDG vary widely. Genetic testing analysis helps in the clinical diagnosis of children with CDG.

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