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1.
Org Lett ; 26(18): 3982-3986, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38690829

RESUMO

Described herein is the development of a visible-light-induced photoredox 1,6-enyne reductive cyclization via selective reduction of a triple bond instead of an activated double bond. The selective 1,6-enyne radical cyclization/carbon═carbon double bond cleavage provided a straightforward route to structurally valuable α,ß-unsaturated γ-lactams. TEMPO-trap experiments, control experiments, and DFT calculations have offered evidence supporting the possible catalytic cycle.

2.
Adv Mater ; : e2312429, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38655823

RESUMO

2D materials such as graphene, MoS2, and hexagonal BN are the most advanced solid lubricating materials with superior friction and anti-wear performance. However, as a typical surface phenomenon, the lubricating properties of 2D materials are largely dependent on the surrounding environment, such as temperature, stress, humidity, oxygen, and other environmental substances. Given the technical challenges in experiment for real-time and in situ detection of microscopic environment-material interaction, recent years have witnessed the acceleration of computational research on the lubrication behavior of 2D materials in realistic environments. This study reviews the up-to-date computational studies for the effect of environmental factors on the lubrication performance of 2D materials, summarizes the theoretical methods in lubrication from classical to quantum-mechanics ones, and emphasizes the importance of quantum method in revealing the lubrication mechanism at atomic and electronic level. An effective simulation method based on ab initio molecular dynamics is also proposed to try to provide more ways to accurately reveal the friction mechanisms and reliably guide the lubricating material design. On the basis of current development, future prospects, and challenges for the simulation and modeling in lubrication with realistic environment are outlined.

3.
Molecules ; 29(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38675603

RESUMO

Due to boron's metalloid properties, aromatic boron reagents are prevalent synthetic intermediates. The direct borylation of aryl C-H bonds for producing aromatic boron compounds offers an appealing, one-step solution. Despite significant advances in this field, achieving regioselective aryl C-H bond borylation using simple and readily available starting materials still remains a challenge. In this work, we attempted to enhance the reactivity of the electron-donor-acceptor (EDA) complex by selecting different bases to replace the organic base (NEt3) used in our previous research. To our delight, when using NH4HCO3 as the base, we have achieved a mild visible-light-mediated aromatic C-H bond borylation reaction with exceptional regioselectivity (rr > 40:1 to single isomers). Compared with our previous borylation methodologies, this protocol provides a more efficient and broader scope for aryl C-H bond borylation through the use of N-Bromosuccinimide. The protocol's good functional-group tolerance and excellent regioselectivity enable the functionalization of a variety of biologically relevant compounds and novel cascade transformations. Mechanistic experiments and theoretical calculations conducted in this study have indicated that, for certain arenes, the aryl C-H bond borylation might proceed through a new reaction mechanism, which involves the formation of a novel transient EDA complex.

4.
Hum Vaccin Immunother ; 20(1): 2335052, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38575149

RESUMO

Emerging SARS-CoV-2 sublineages continue to cause serious COVID-19 disease, but most individuals have not received any COVID-19 vaccine for >1 year. Assessment of long-term effectiveness of bivalent COVID-19 vaccines against circulating sublineages is important to inform the potential need for vaccination with updated vaccines. In this test-negative study at Kaiser Permanente Southern California, sequencing-confirmed BA.4/BA.5- or XBB-related SARS-CoV-2-positive cases (September 1, 2022 to June 30, 2023), were matched 1:3 to SARS-CoV-2-negative controls. We assessed mRNA-1273 bivalent relative (rVE) and absolute vaccine effectiveness (VE) compared to ≥2 or 0 doses of original monovalent vaccine, respectively. The rVE analysis included 20,966 cases and 62,898 controls. rVE (95%CI) against BA.4/BA.5 at 14-60 days and 121-180 days was 52.7% (46.9-57.8%) and 35.5% (-2.8-59.5%) for infection, and 59.3% (49.7-67.0%) and 33.2% (-28.2-68.0%) for Emergency Department/Urgent Care (ED/UC) encounters. For BA.4/BA.5-related hospitalizations, rVE was 71.3% (44.9-85.1%) and 52.0% (-1.2-77.3%) at 14-60 days and 61-120 days, respectively. rVE against XBB at 14-60 days and 121-180 days was 48.8% (33.4-60.7%) and -3.9% (-18.1-11.3%) for infection, 70.7% (52.4-82.0%) and 15.7% (-6.0-33.2%) for ED/UC encounters, and 87.9% (43.8-97.4%) and 57.1% (17.0-77.8%) for hospitalization. VE and subgroup analyses (age, immunocompromised status, previous SARS-CoV-2 infection) results were similar to rVE analyses. rVE of mRNA-1273 bivalent vaccine against BA.4/BA.5 and XBB infections, ED/UC encounters, and hospitalizations waned over time. Periodic revaccination with vaccines targeting emerging variants may be important in reducing COVID-19 morbidity and mortality.


Assuntos
COVID-19 , Vacinas de mRNA , Humanos , Vacina de mRNA-1273 contra 2019-nCoV , Vacinas contra COVID-19 , SARS-CoV-2/genética , COVID-19/prevenção & controle , Vacinas Combinadas
5.
J Cardiothorac Surg ; 19(1): 155, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532497

RESUMO

BACKGROUND: To demonstrate the effectiveness and feasibility of robotic portal resection (RPR) for mediastinal tumour using a prospectively collected database. METHODS: Data from 73 consecutive patients with mediastinal tumours who underwent RPRs were prospectively collected from August 2018 to April 2023. All patients underwent chest and abdominal enhanced computed tomography (CT) and preoperative multidisciplinary team (MDT) discussion. The patients were stratified into two groups based on tumour size: Group A (tumour size < 4 cm) and Group B (tumour size ≥ 4 cm). General clinical characteristics, surgical procedures, and short outcomes were promptly recorded. RESULTS: All of the cases were scheduled for RPRs. One patient (1/73, 1.4%) was switched to a small utility incision approach because of extensive pleural adhesion. Two patients (2.8%) converted to sternotomy, however, no perioperative deaths occurred. Most of the tumours were located in the anterior mediastinum (51/73, 69.9%). Thymoma (27/73, 37.0%) and thymic cyst (16/73, 21.9%) were the most common diagnoses. The median diameter of tumours was 3.2 cm (IQR, 2.4-4.5 cm). The median total operative time was 61.0 min (IQR, 50.0-90.0 min). The median intraoperative blood loss was 20 mL (IQR, 5.0-30.0 ml), and only one patient (1.4%) experienced an intraoperative complication. The median length of hospital stay was 3 days (IQR, 2-4 days). Compared with Group A, the median total operative time and console time of Group B were significantly longer (P = 0.006 and P = 0.003, respectively). The volume of drainage on the first postoperative day was greater in group B than in group A (P = 0.013). CONCLUSION: RPR is a safe and effective technique for mediastinal tumour treatment, which can expand the application of minimally invasive surgery for the removal of complicated mediastinal tumours.


Assuntos
Neoplasias do Mediastino , Procedimentos Cirúrgicos Robóticos , Robótica , Timoma , Neoplasias do Timo , Humanos , Neoplasias do Mediastino/cirurgia , Robótica/métodos , Neoplasias do Timo/cirurgia , Timoma/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
6.
J Med Chem ; 67(8): 6793-6809, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38546542

RESUMO

Butyrylcholinesterase (BChE) is a promising biomarker and effective therapeutic target for Alzheimer's disease (AD). Herein, we designed a BChE-activated near-infrared (NIR) probe, DTNP, which could be activated by BChE and inhibit its enzymatic activity. DTNP is composed of a cyclopropane moiety as the recognition unit, a NIR fluorophore hemicyanine as the NIR reporter, and a BChE inhibitor as the therapeutic unit. DTNP specifically binds BChE with high sensitivity and exhibits strong "turn-on" NIR fluorescence as well as nerve cell protection. In vivo imaging shows DTNP has favorable blood-brain barrier permeability and long-term tracking ability with preliminary competence in AD diagnosis. DTNP can significantly inhibit BChE activity, promote the release of ACh, and rescue learning deficits and cognitive impairment. Therefore, DTNP, the first reported and partially validated theranostic probe for the detection of BChE in AD, may provide a foundation and inspiration for imaging and therapy in AD.


Assuntos
Doença de Alzheimer , Butirilcolinesterase , Inibidores da Colinesterase , Corantes Fluorescentes , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Butirilcolinesterase/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Animais , Humanos , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Camundongos , Nanomedicina Teranóstica , Barreira Hematoencefálica/metabolismo , Masculino , Imagem Óptica
7.
J Org Chem ; 89(7): 5060-5068, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38525894

RESUMO

Radical cyclization has been demonstrated to be an efficient method to access functionalized heterocycles from easily accessible raw materials. Described herein is the development of a photocatalytic proton-coupled electron transfer (PCET) strategy for the synthesis of isoquinoline-1,3-diones using readily prepared naphthalimide (NI)-based organic photocatalysts. The process features free metal-complex photocatalysts, acids, and mild reaction conditions. This mild radical cyclization protocol has a broad substrate scope and can be effectively applied to a variety of medicinally relevant substrates. Furthermore, control experiments were conducted to elucidate the mechanism of this visible light-induced methodology.

8.
RSC Adv ; 14(3): 1902-1908, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38192317

RESUMO

We reported a novel electron-donor-acceptor (EDA) photocatalyst formed in situ from isoquinoline, a diboron reagent, and a weak base. To further optimize the efficiency of this photocatalyst, Density Functional Theory (DFT) calculations were conducted to investigate the substituent effects on the properties of vertical excitation energy and redox potential. Subsequently, we experimentally validated these effects using a broader range of substituents and varying substitution positions. Notably, the 4-NH2 EDA complex derived from 4-NH2-isoquinoline exhibits the highest photocatalytic efficiency, enabling feasible metal free borylation of aromatic C-H bond and detosylaion of Ts-anilines under green and super mild conditions. These experimental results demonstrate the effectiveness of our strategy for photocatalyst optimization.

9.
Nanomaterials (Basel) ; 14(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276744

RESUMO

Field-effect transistor (FET) biosensors can be used to measure the charge information carried by biomolecules. However, insurmountable hysteresis in the long-term and large-range transfer characteristic curve exists and affects the measurements. Noise signal, caused by the interference coefficient of external factors, may destroy the quantitative analysis of trace targets in complex biological systems. In this report, a "rectified signal" in the output characteristic curve, instead of the "absolute value signal" in the transfer characteristic curve, is obtained and analyzed to solve these problems. The proposed asymmetric Schottky barrier-generated MoS2/WTe2 FET biosensor achieved a 105 rectified signal, sufficient reliability and stability (maintained for 60 days), ultra-sensitive detection (10 aM) of the Down syndrome-related DYRK1A gene, and excellent specificity in base recognition. This biosensor with a response range of 10 aM-100 pM has significant application potential in the screening and rapid diagnosis of Down syndrome.

10.
BMC Surg ; 23(1): 330, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891506

RESUMO

BACKGROUND: Both video-assisted thoracoscopic surgery (VATS) thymectomy and robot-assisted thoracoscopic surgery (RATS) thymectomy have been suggested as technically sound approaches for early-stage thymic epithelial tumors. However, the choice of VATS or RATS thymectomy for large and advanced thymic epithelial tumors remains controversial. In this study, the perioperative outcomes of VATS and RATS thymectomy were compared in patients with large thymic epithelial tumors (size ≥5.0 cm). METHODS: A total of 113 patients with large thymic epithelial tumors who underwent minimally invasive surgery were included. Sixty-three patients underwent RATS, and 50 patients underwent VATS. Patient characteristics and perioperative variables were compared. RESULTS: Compared with the VATS group, the RATS group experienced a shorter operation time (median: 110 min vs.130 min; P < 0.001) and less blood loss (30.00 ml vs. 100.00 ml, P < 0.001). No patients in the RATS group needed conversion to open surgery, but in the VATS series, five patients required conversion to open procedures (0% vs. 14.29%, P = 0.054). The rate of concomitant resection in the RATS group was similar to that in the VATS group (11.43% vs. 5.71%; P = 0.673). There was no significant difference between the two groups in the duration of chest tube (P = 0.587), postoperative complications (P = 1.000), and the duration of postoperative hospital stay (P = 0.141). CONCLUSION: For large thymic epithelial tumors, RATS thymectomy can be performed safely and effectively in a radical fashion. Due to the advanced optics and precise instrument control, concomitant resections can be easily achieved in larger thymic epithelial tumors using the robotic approach.


Assuntos
Neoplasias Epiteliais e Glandulares , Robótica , Neoplasias do Timo , Humanos , Timectomia/métodos , Cirurgia Torácica Vídeoassistida/métodos , Estudos Retrospectivos , Neoplasias do Timo/cirurgia , Neoplasias do Timo/patologia , Neoplasias Epiteliais e Glandulares/cirurgia
11.
Mol Plant ; 16(9): 1379-1395, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37563832

RESUMO

The RIPENING-INHIBITOR (RIN) transcriptional factor is a key regulator governing fruit ripening. While RIN also affects other physiological processes, its potential roles in triggering interactions with the rhizosphere microbiome and plant health are unknown. Here we show that RIN affects microbiome-mediated disease resistance via root exudation, leading to recruitment of microbiota that suppress the soil-borne, phytopathogenic Ralstonia solanacearum bacterium. Compared with the wild-type (WT) plant, RIN mutants had different root exudate profiles, which were associated with distinct changes in microbiome composition and diversity. Specifically, the relative abundances of antibiosis-associated genes and pathogen-suppressing Actinobacteria (Streptomyces) were clearly lower in the rhizosphere of rin mutants. The composition, diversity, and suppressiveness of rin plant microbiomes could be restored by the application of 3-hydroxyflavone and riboflavin, which were exuded in much lower concentrations by the rin mutant. Interestingly, RIN-mediated effects on root exudates, Actinobacteria, and disease suppression were evident from the seedling stage, indicating that RIN plays a dual role in the early assembly of disease-suppressive microbiota and late fruit development. Collectively, our work suggests that, while plant disease resistance is a complex trait driven by interactions between the plant, rhizosphere microbiome, and the pathogen, it can be indirectly manipulated using "prebiotic" compounds that promote the recruitment of disease-suppressive microbiota.


Assuntos
Microbiota , Microbiologia do Solo , Rizosfera , Resistência à Doença , Raízes de Plantas/microbiologia , Plantas/microbiologia , Bactérias , Exsudatos e Transudatos
13.
Chem Rev ; 123(16): 9940-9981, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37561162

RESUMO

A survey of protein databases indicates that the majority of enzymes exist in oligomeric forms, with about half of those found in the UniProt database being homodimeric. Understanding why many enzymes are in their dimeric form is imperative. Recent developments in experimental and computational techniques have allowed for a deeper comprehension of the cooperative interactions between the subunits of dimeric enzymes. This review aims to succinctly summarize these recent advancements by providing an overview of experimental and theoretical methods, as well as an understanding of cooperativity in substrate binding and the molecular mechanisms of cooperative catalysis within homodimeric enzymes. Focus is set upon the beneficial effects of dimerization and cooperative catalysis. These advancements not only provide essential case studies and theoretical support for comprehending dimeric enzyme catalysis but also serve as a foundation for designing highly efficient catalysts, such as dimeric organic catalysts. Moreover, these developments have significant implications for drug design, as exemplified by Paxlovid, which was designed for the homodimeric main protease of SARS-CoV-2.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Polímeros
14.
ACS Chem Neurosci ; 14(17): 3226-3248, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37561893

RESUMO

Concomitant inhibition of butyrylcholinesterase (BChE) and histone deacetylase 6 (HDAC6) is supposed to be effective in the treatment of Alzheimer's disease (AD). Inspired by our previous efforts in designing BChE inhibitors, herein, selective BChE and HDAC6 dual inhibitors were successfully identified through the fusion of the core pharmacophoric moiety of BChE and HDAC6 inhibitors. After the structure-activity relationship (SAR) studies, two compounds (24g and 29a) were confirmed to have superior inhibitory activity against BChE (the IC50 against hBChE are 4.0 and 1.8 nM, respectively) and HDAC6 (the IC50 against HDAC6 are 8.9 and 71.0 nM, respectively). These two compounds showed prominently neuroprotective effects in vitro, potent reactive oxygen species (ROS) scavenging effects, and effective metal ion (Fe2+ and Cu2+) chelation. In addition, they exhibited pronounced inhibition of phosphorylated tau and a moderate immunomodulatory effect, with a lack of neurotoxicity at the cellular level. In vivo studies showed that both 24g and 29a ameliorated the cognitive impairment in an Aß1-42-induced mouse model at a low dosage (2.5 mg/kg). Our data demonstrated that BChE/HDAC6 dual inhibitors could establish the basis for a potential new symptomatic and disease-modifying strategy to treat AD.


Assuntos
Doença de Alzheimer , Butirilcolinesterase , Camundongos , Animais , Butirilcolinesterase/metabolismo , Desacetilase 6 de Histona , Inibidores da Colinesterase/farmacologia , Relação Estrutura-Atividade , Inibidores de Histona Desacetilases/farmacologia , Acetilcolinesterase/metabolismo
15.
BMJ ; 382: e076222, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558240

RESUMO

OBJECTIVES: To characterize the long term risk of death and hospital readmission after an index admission with covid-19 among Medicare fee-for-service beneficiaries, and to compare these outcomes with historical control patients admitted to hospital with influenza. DESIGN: Retrospective cohort study. SETTING: United States. PARTICIPANTS: 883 394 Medicare fee-for-service beneficiaries age ≥65 years discharged alive after an index hospital admission with covid-19 between 1 March 2020 and 31 August 2022, compared with 56 409 historical controls discharged alive after a hospital admission with influenza between 1 March 2018 and 31 August 2019. Weighting methods were used to account for differences in observed characteristics. MAIN OUTCOME MEASURES: All cause death within 180 days of discharge. Secondary outcomes included first all cause readmission and a composite of death or readmission within 180 days. RESULTS: The covid-19 cohort compared with the influenza cohort was younger (77.9 v 78.9 years, standardized mean difference -0.12) and had a lower proportion of women (51.7% v 57.3%, -0.11). Both groups had a similar proportion of black beneficiaries (10.3% v 8.1%, 0.07) and beneficiaries with dual Medicaid-Medicare eligibility status (20.1% v 19.2%; 0.02). The covid-19 cohort had a lower comorbidity burden, including atrial fibrillation (24.3% v 29.5%, -0.12), heart failure (43.4% v 49.9%, -0.13), and chronic obstructive pulmonary disease (39.2% v 52.9%, -0.27). After weighting, the covid-19 cohort had a higher risk (ie, cumulative incidence) of all cause death at 30 days (10.9% v 3.9%; standardized risk difference 7.0%, 95% confidence interval 6.8% to 7.2%), 90 days (15.5% v 7.1%; 8.4%, 8.2% to 8.7%), and 180 days (19.1% v 10.5%; 8.6%, 8.3% to 8.9%) compared with the influenza cohort. The covid-19 cohort also experienced a higher risk of hospital readmission at 30 days (16.0% v 11.2%; 4.9%, 4.6% to 5.1%) and 90 days (24.1% v 21.3%; 2.8%, 2.5% to 3.2%) but a similar risk at 180 days (30.6% v 30.6%;-0.1%, -0.5% to 0.3%). Over the study period, the 30 day risk of death for patients discharged after a covid-19 admission decreased from 17.9% to 7.2%. CONCLUSIONS: Medicare beneficiaries who were discharged alive after a covid-19 hospital admission had a higher post-discharge risk of death compared with historical influenza controls; this difference, however, was concentrated in the early post-discharge period. The risk of death for patients discharged after a covid-19 related hospital admission substantially declined over the course of the pandemic.


Assuntos
COVID-19 , Influenza Humana , Humanos , Feminino , Idoso , Estados Unidos/epidemiologia , Readmissão do Paciente , Estudos Retrospectivos , Alta do Paciente , Assistência ao Convalescente , Influenza Humana/epidemiologia , Medicare , Hospitais
16.
Vasc Med ; 28(6): 564-570, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37638877

RESUMO

BACKGROUND: Persons living with human immunodeficiency virus (HIV, PLWH) have an increased risk of peripheral artery disease (PAD) in comparison to the general population. However, a gap remains in understanding optimal management for this condition. This study assesses longitudinal outcomes associated with peripheral endovascular intervention (PVI) for PAD among PLWH. METHODS: All Medicare fee-for-service patients undergoing femoropopliteal artery PVI between April 1, 2015 and December 31, 2018 were identified and stratified by HIV serostatus. The primary outcome was major adverse limb events (MALE), defined as major amputation or arterial embolism/thrombosis following an index procedure. The subdistribution hazard was used to evaluate the association between HIV serostatus and MALE, accounting for the competing risk of death. Results were adjusted for sociodemographics and major comorbidities. RESULTS: Of 168,553 patients who underwent PVI, 357 (0.21%) were PLWH. The average age was 77.0 ± 7.6 years; 80.3% had hypertension, 70.3% had hyperlipidemia, and 24.6% had tobacco use disorder. Compared to those without HIV, PLWH were younger and had a higher burden of cardiovascular risk factors. MALE were substantially more frequent among PLWH, with a cumulative incidence of 24.6%, compared to 14.5% among those without HIV. The adjusted subdistribution hazard ratio was 1.26 (95% CI 1.00-1.58, p = 0.05). The use of guideline-directed statin therapy was low in both groups in the 90 days following revascularization (57.9% in PLWH vs 58.1% in those without HIV, p = 0.95). CONCLUSION: Among US Medicare beneficiaries, PLWH had poorer long-term outcomes following PVI. Greater attention to the management of symptomatic PAD is warranted for the HIV population, particularly following revascularization.


Assuntos
Procedimentos Endovasculares , Infecções por HIV , Doença Arterial Periférica , Idoso , Humanos , Estados Unidos/epidemiologia , Idoso de 80 Anos ou mais , HIV , Fatores de Risco , Resultado do Tratamento , Estudos Retrospectivos , Medicare , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/epidemiologia , Doença Arterial Periférica/terapia , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Procedimentos Endovasculares/efeitos adversos
17.
J Agric Food Chem ; 71(30): 11692-11703, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37483134

RESUMO

Most GH11 family endo-ß-1,4-xylanases contain a propeptide region linked to the N-terminal region. The mechanistic basis of this region harboring key regulation information for enzyme function, however, remains poorly understood. We reported an investigation on the allosteric regulation mechanism of the propeptide based on biochemical characterization, molecular dynamics simulations, and evolutionary analysis. We discovered that the mutant of truncated propeptide shows a remarkably increased thermal stability (melting temperature increased by 11.5 °C) and catalytic efficiency (1.7-fold kcat/Km value of wild type). Molecular dynamics simulations reveal that long-range fluctuations in the propeptide lead to a conformational perturbation in the catalytic pocket and the thumb region. The probability of sampling the active conformation during the glycosylation step is reduced (i.e., catalytic efficiency). In-depth sequence analysis indicates that the propeptide has a strong plasticity and degeneration trend, and propeptide truncation experiments of the homologous enzyme XynB validated the feasibility of the truncation strategy. This work reveals the role of GH11 family propeptides in functional regulation and provides a straightforward and practical method to increase the robustness of GH11 family xylanases.


Assuntos
Endo-1,4-beta-Xilanases , Simulação de Dinâmica Molecular , Domínio Catalítico , Regulação Alostérica , Temperatura , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática
18.
Thorac Cancer ; 14(16): 1512-1519, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37128686

RESUMO

BACKGROUND: To explore whether robotic lobectomy (RL) is superior to video-assisted lobectomy (VAL) in terms of short-term outcomes in patients with pulmonary neoplasms. METHODS: From January 30, 2019 to February 28, 2022, a series of consecutive minimally invasive lobectomies were performed for patients with pulmonary neoplasms. Perioperative outcomes such as operation time, blood loss, dissected lymph nodes (LNs), surgical complications, postoperative pain control, length of postoperative stay in hospital, and total cost of hospitalization were compared. RESULTS: A total of 336 cases including 173 RLs and 163 VALs were enrolled. Baseline characteristics were comparable between groups. RLs were associated with shorter operation time (median [interquadrant range, IQR], 107 min [90-130] vs. 120 min [100-149], p < 0.001), less blood loss (median [IQR], 50 mL [30-60] vs. 50 mL [50-80], p = 0.02), and lower blood transfusion rate (3.5% vs. 9.8%, p = 0.02) compared with VALs. More LNs were harvested by the robotic approach (median [IQR], 29 [20-41] vs. 22 [15-45], p = 0.04). The incidences of conversion, major postoperative complications, extra analgesic usage, and postoperative length of stay were all comparable between the RL and VAL groups. As predicted, the total cost of hospitalization was greater in the RL group (median [IQR], $16728.35 [15682.16-17872.15] vs. $10713.47 [9662.13-11742.15], p < 0.001). CONCLUSION: RL improved surgical efficacy with shortened operative time, less blood loss, and more thorough LN dissection compared with VAL, compromised by higher cost.


Assuntos
Neoplasias Pulmonares , Procedimentos Cirúrgicos Robóticos , Humanos , Resultado do Tratamento , Estudos Retrospectivos , Pneumonectomia/efeitos adversos , Neoplasias Pulmonares/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Tempo de Internação , Cirurgia Torácica Vídeoassistida/efeitos adversos
19.
Angew Chem Int Ed Engl ; 62(33): e202303075, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37202371

RESUMO

A highly enantioselective catalytic system for exo-Diels-Alder reactions was developed based on the newly discovered bispyrrolidine diboronates (BPDB). Activated by various Lewis or Brønsted acids, BPDB can catalyze highly stereoselective asymmetric exo-Diels-Alder reactions of monocarbonyl-based dienophiles. When 1,2-dicarbonyl-based dienophiles are used, the catalyst can sterically distinguish between the two binding sites, which leads to highly regioselective asymmetric Diels-Alder reactions. BPDB can be prepared as crystalline solids on a large scale and are stable under ambient condition. Single-crystal X-ray analysis of the structure for acid-activated BPDB indicated that its activation involves cleavage of a labile B←N bond.

20.
J Thorac Dis ; 15(3): 1086-1095, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37065552

RESUMO

Background: Postoperative pneumothorax can lead to additional invasive intervention and extended hospitalization. The effect of initiative pulmonary bullectomy (IPB) during the esophagectomy on preventing postoperative pneumothorax remains controversial. This study evaluated the efficacy and safety of IPB in patients who underwent minimally invasive esophagectomy (MIE) for esophageal carcinoma complicated by ipsilateral pulmonary bullae. Methods: Data from 654 consecutive patients with esophageal carcinoma who underwent MIE from January 2013 to May 2020 were retrospectively collected. A total of 109 patients who had a definite diagnosis of ipsilateral pulmonary bullae were recruited and classified into two groups: the IPB group and the control group (CG). Propensity score matching (PSM, match ratio =1:1), incorporating preoperative clinical features, was used to compare the perioperative complications and analyze efficacy and safety between IPB and control group. Results: The incidences of postoperative pneumothorax in the IPB and control groups was 3.13% and 40.63% respectively, with a significant difference (P<0.001). Logistic analyses indicated that removing ipsilateral bullae was associated with a lower risk (OR 0.030; 95% CI: 0.003-0.338; P=0.005) of incident postoperative pneumothorax. No significant difference was found between the two groups in terms of the incidence of anastomotic leakage (6.25% vs. 3.13%, P=1.000), arrhythmia (3.13% vs. 3.13%, P=1.000), chylothorax (0% vs. 3.13%, P=1.000) and other common complications. Conclusions: In esophageal cancer patients with ipsilateral pulmonary bullae, IPB performed in the same anesthesia process is an effective and safe method for the prevention of postoperative pneumothorax, allowing for a shorter postoperative rehabilitation time, and it does not exert unfavorable effects on complications.

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