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1.
Nat Commun ; 14(1): 578, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36732512

RESUMO

Covalent organic frameworks have shown considerable application potential and exceptional properties in the construction of stimulus-responsive materials. Here, we designed a sweat-responsive covalent organic framework film for material-based fingerprint liveness detection. When exposed to human sweat, the COFTPDA-TFPy film can transform from yellow to red. The COFTPDA-TFPy film, when touched by living fingers, can produce the naked-eye-identified fingerprint pattern through the sweat-induced color change, while artificial fake fingerprints cannot. This technique, which we named material-based liveness detection, can thus intuitively discern living fingers from fake fingerprints with a 100% accuracy rate. Additionally, the distribution of sweat pores on human skin can also be collected and analyzed by shortening the contact time. By merely washing them with ethanol, all the samples can be utilized again. This work inventively accomplished material-based liveness detection and naked-eye-identified sweat pore analysis and highlighted their potential for use in clinical research and personal identification.

2.
J Clin Anesth ; 86: 111068, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736209

RESUMO

STUDY OBJECTIVE: To assess the impact of intraoperative dexmedetomidine on long-term outcomes of older patients following major noncardiac surgery mainly for cancer. DESIGN: A long-term follow-up of patients enrolled in a randomized trial. SETTING: The initial trial was performed in a tertiary care hospital in Beijing, China. PARTICIPANTS: Patients aged 60 years or older who were scheduled for major noncardiac surgery. INTERVENTION: Participants were randomized to receive either dexmedetomidine (a loading dose of 0.6 µg/kg over 10 min, followed by a continuous infusion of 0.5 µg/kg/h until 1 h before end of surgery) or placebo during anesthesia. MEASUREMENTS: The primary endpoint was overall survival. Secondary endpoints included recurrence-free survival and event-free survival. Cox proportional hazard models were used to adjust for predefined confounding factors. Propensity score matching was employed for sensitive analysis. RESULTS: Among 620 patients who were randomized in the initial trial, 619 were included in the long-term analysis (mean age 69 years, 40% female, 77% oncological surgery). The median follow-up duration was 42 months (interquartile range 41 to 45). Overall survival did not differ between the two groups: there were 49/309 (15.9%) deaths with dexmedetomidine versus 63/310 (20.3%) with placebo (adjusted hazard ratio [HR] 0.78, 95% CI 0.53-1.13, P = 0.187). Recurrence-free survival was improved with dexmedetomidine (68/309 [22.0%] events with dexmedetomidine versus 98/310 [31.6%] with placebo; adjusted HR 0.67, 95% CI 0.49-0.92, P = 0.012). Event-free survival was also improved with dexmedetomidine (120/309 [38.8%] events with dexmedetomidine versus 145/310 [46.8%] with placebo; adjusted HR 0.78, 95% CI 0.61-1.00, P = 0.047). Results were similar after propensity-score matching and in the subgroup of cancer patients. CONCLUSIONS: In older patients having major noncardiac surgery mainly for cancer, intraoperative dexmedetomidine did not improve overall survival but was associated with improved recurrence-free and event-free survivals.

3.
Clin Med Insights Oncol ; 17: 11795549221146652, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36726607

RESUMO

Background: Risk stratification of patients with cervical cancer accompanied by positive lymph nodes (stage IIIC) (the 2018 International Federation of Gynecology and Obstetrics [FIGO] new staging system) yields a clinically heterogeneous group. In this study, we investigated the prognostic performance of the 2018 FIGO staging system for stage IIIC cervical cancer. Methods: The study included patients with stage III cervical cancer based on the 2018 FIGO staging system, who visited Chongqing University Cancer Hospital between January 2011 and December 2014. Kaplan-Meier curves were generated to evaluate overall survival (OS), which was compared using the log-rank test. The Cox proportional hazard regression model was used for multivariable analysis. Results: A total of 418 patients were eligible for analysis. The 5-year OS was 54.1% for stage IIIC1, 43.3% for stage IIIA, 40.6% for stage IIIB, and 23.1% for stage IIIC2 (P < .001). Multivariable analysis revealed that compared with stages IIIA (hazard ratio [HR] 1.432, 95% confidence interval [CI] 0.867-2.366, P = .161) and IIIB (HR 1.261, 95% CI 0.871-1.827, P = .219), stage IIIC1 cancer was not significantly associated with an increased mortality risk. Stage IIIC2 was independently associated with an increased mortality risk compared with stages IIIA (HR 2.958, 95% CI 1.757-4.983, P < .001) and IIIB (HR 2.606, 95% CI 1.752-3.877, P < .001). We stratified patients with stage IIIC1 based on the T stage. The 5-year OS was significantly longer in patients with stage IIIC1 (T1) than in those with stage IIIA (P = .004) or IIIB (P < .001). Analysis of multiple factors revealed that the mortality risk was 2.75-fold higher in patients with stage IIIC1pN>2 than in patients with stage IIIC1pN1-2 (HR 2.753, 95% CI 1.527-4.965, P = .001). Conclusions: Patients with stage IIIC1 cervical cancer showed heterogeneous clinical characteristics that reflected variable prognoses, depending on the T stage and the extent of pelvic lymph node metastases.

4.
Int J Biol Macromol ; : 123468, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36731702

RESUMO

Disulfide bonds in proteins have strongly influence on the folding efficiency by constraining the conformational space. The inefficient disulfide bond formation of proteins is the main limiting factor of enzyme activity and stability. This study aimed to increase the activity of disulfide-bond-containing proteins via promoting disulfide bonds formation in Bacillus licheniformis. Initially, the glutamate decarboxylase GAD from Escherichia coli was selected as the model protein and introduced into the B. licheniformis. Then, the disulfide isomerase and oxidoreductase from different sources were excavated and overexpressed successively to improve the catalytic efficiency of GAD. The final engineered B. licheniformis showed significantly improved GAD specific activity (from 10.4 U/mg to 80.0 U/mg), which also presented perfect adaptability for other disulfide-bond-containing proteins, for instance, UDP-glucosyltransferase from Arabidopsis thaliana. Taken together, our work demonstrated that the activity of GAD in B. licheniformis was regulated by the disulfide bonds formation status and provided a promising platform for the expression of disulfide-bond-containing proteins.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36731792

RESUMO

BACKGROUND & AIMS: Liver ischemia and reperfusion (IR) injury represents a major risk factor in both partial hepatectomy and liver transplantation. Nerve injury-induced protein 1 (Ninj1) is widely recognized as an adhesion molecule in leukocyte trafficking under inflammatory conditions, but its role in regulating innate immune during liver IR injury remains unclear. METHODS: Myeloid Ninj1 deficient mice were generated by bone marrow chimeric models using Ninj1 knockout (KO) mice and wild type (WT) mice. In vivo, liver partial warm ischemia model was applied. Liver injury and hepatic inflammation were investigated. In vitro, primary Kupffer cells (KCs) isolated from Ninj1 KO and WT mice were used to explore the function and mechanism of Ninj1 in modulating KCs inflammation upon LPS stimulation. RESULTS: Ninj1 deficiency in KCs protected mice against liver IR injury during the later phase of reperfusion, especially in neutrophil infiltration, intrahepatic inflammation, and hepatocyte apoptosis. This prompted ischemia-primed KCs to decrease proinflammatory cytokine production. In vitro and in vivo, using small interfering RNA against Dual specificity Phosphatase 1 (DUSP1), we found that Ninj1 deficiency diminished the inflammatory response in KCs and neutrophil infiltration through DUSP1-dependent deactivation of the JNK and p38 pathways. Sivelestat, a neutrophil elastase inhibitor, functioned similarly to Ninj1 deficiency, resulting in both mitigated hepatic IR injury in mice and a more rapid recovery of liver function in patients undergoing liver resection. CONCLUSIONS: Ninj1/Dusp1 axis contributes to liver IR injury by regulating the proinflammatory response of KCs, and influences neutrophil infiltration, partly by subsequent regulation of CXCL1 production post-IR.

6.
J Investig Med ; 71(2): 92-100, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36733996

RESUMO

The objective of this study was to determine the relationship between renal injury and inflammatory response induced by high-fat diet in rabbits and the interventional effect of allisartan. Fifteen 6-week-old healthy male rabbits were randomly divided into three groups: normal control (NC) group, high-lipid diet (HLD) group, high-lipid diet and allisartan (HLD+ALST) group. After allisartan treatment for 12 weeks, changes in total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), serum creatinine (Scr) and blood urea nitrogen (BUN) were measured enzymatically in the three groups. The left side of the kidney tissue was kept for paraffin section, and HE staining, periodic acid-Schiff (PAS) staining and Masson staining were used to observe the renal pathologic changes. TC, TG, LDL-C, Scr and BUN levels were all higher and HDL-C levels were lower in the HLD group compared with the NC group. Compared with the HLD group, Scr and BUN levels were significantly decreased in the HLD+ALST group. The results of HE staining showed that allisartan improved the changes of renal tissue morphology in rabbits on high-fat diet, reduced glomerular mesangial cell proliferation and improved glomerulosclerosis; PAS staining showed that glomerular glycogen deposition was reduced and glomerular red staining was significantly lighter; Masson staining showed that renal tubular blue-stained collagen fibers were reduced. In conclusion, hyperlipidemia can lead to aberrant expression of multiple cellular proteins and kidney tissue morphological damage in rabbits. On the other hand, allisartan attenuated renal injury and the mechanism may be related to the downregulation of the inflammatory response.

7.
ACS Nano ; 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36727670

RESUMO

Personal thermal management (PTM) is a promising approach for maintaining the thermal comfort zone of the human body while minimizing the energy consumption of indoor buildings. Recent studies have reported the development of numerous advanced textiles that enable PTM systems to regulate body temperature and are comfortable to wear. Herein, recent advancements in thermoregulatory clothing for PTM are discussed. These advances in thermoregulatory clothing have focused on enhancing the control of heat dissipation between the skin and the localized environment. We primarily summarize research on advanced clothing that controls the heat dissipation pathways of the human body, such as radiation- and conductance-controlled clothing. Furthermore, adaptive clothing such as dual-mode textiles, which can regulate the microclimate of the human body, as well as responsive textiles that address both thermal performance (warming and/or cooling) and wearability are discussed. Finally, we include a discussion on significant challenges and perspectives in this field, including large-scale production, smart textiles, bioinspired clothing, and AI-assisted clothing. This comprehensive review aims to further the development of sustainably manufactured advanced clothing with superior thermal performance and outstanding wearability for PTM in practical applications.

9.
Microbiol Spectr ; : e0433322, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36728419

RESUMO

A novel circovirus species was identified in farmed pigs and designated porcine circovirus 4 (PCV4); it has recently been proved to be pathogenic to piglets. However, little is known about its cross-species transmission, and there is no evidence of PCV4 in dogs. A total of 217 fecal samples were collected from diarrheal dogs in Henan Province, China, and tested for the presence of PCV4 using a real-time PCR assay. Among the 217 samples, the total positivity rate for PCV4 was 5.99% (13/217 samples), with rates of 7.44% and 4.17% in 2020 and 2021, respectively. PCV4 was detected in dogs in 6 of 10 cities, demonstrating that PCV4 could be detected in dogs in Henan Province, China. One PCV4 strain (HN-Dog) was sequenced in this study and shared high levels of identity (97.9% to 99.6%) with reference strains at the genome level. Phylogenetic analysis based on complete genome sequences of HN-Dog and 42 reference strains showed that the HN-Dog strain was closely related to 3 PCV4 reference strains (from pig, raccoon dog, and fox) but differed genetically from other viruses in the genus Circovirus. Three genotypes, i.e., PCV4a, PCV4b, and PCV4c, were confirmed by phylogenetic analysis of complete genome sequences of 42 PCV4 strains, and one amino acid variation in Rep protein (V239L) and three amino acid variations in Cap protein (N27S, R28G, and M212L) were considered conserved genotype-specific molecular markers. In conclusion, the present study is the first to report the discovery of the PCV4 genome in dogs, and the association between PCV4 infection and diarrhea warrants further study. IMPORTANCE This study is the first to report the presence of PCV4 in dogs worldwide, and the first complete genome sequence was obtained from a dog affected with diarrhea. Three genotypes of PCV4 strains (PCV4a, PCV4b, and PCV4c) were determined, as supported by specific amino acid markers (V239L for open reading frame 1 [ORF1] and N27S R28G and M212L for ORF2). These findings help us understand the current status of intestinal infections in pet dogs in Henan Province, China, and also prompted us to accelerate research on the pathogenesis, epidemiology, and cross-species transmission of PCV4.

10.
Chin Med J (Engl) ; 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36728571

RESUMO

BACKGROUND: Sepsis is a serious disease caused by infection. Aminophylline has anti-asthma and anti-inflammatory effects. We aimed to explore the safety and effect of aminophylline in sepsis. METHODS: We conducted a clinical randomized controlled trial involving 100 patients diagnosed with sepsis within 48 h after intensive care unit (ICU) admission in two sites. All patients were randomized in a 1:1 ratio to receive standard therapy with or without aminophylline. The primary clinical outcome was all-cause mortality at 28 days. RESULTS: From September 27, 2018 to February 12, 2020, we screened 277 septic patients and eventually enrolled 100 patients, with 50 assigned to the aminophylline group and 50 to the usual-care group. At 28 days, 7 of 50 patients (14.0%) in the aminophylline group had died, compared with 16 of 50 (32.0%) in the usual-care group (P = 0.032). Cox regression showed that the aminophylline group had a lower hazard of death (hazard ratio = 0.312, 95% confidence interval: 0.129-0.753). Compared with the usual-care group, patients in the aminophylline group had a longer survival time (P = 0.039 by the log-rank test). The effects of aminophylline on vasopressor dose, oxygenation index, and sequential organ failure assessment score were time-dependent with treatment. There were no significant differences in total hospitalization days, ICU hospitalization days, and rates of serious adverse events (all P > 0.05). No adverse events were observed in the trial. CONCLUSIONS: Aminophylline as an adjunct therapy could significantly reduce the risk of death and prolong the survival time of patients with sepsis. TRIAL REGISTRATION: ChiCTR.org.cn, ChiCTR1800019173.

11.
Nanoscale ; 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36722749

RESUMO

Carbon dots (CDs) with deep-blue thermally activated delayed fluorescence (TADF) of more than 2 s were developed, exhibiting the longest lifetime to date. In contrast to the established deep-blue TADF systems, this developed CD-based system (BNCDs) could be facilely and effectively synthesized, and more impressively, the emission lasted for more than 16 s (to the naked eye). XRD, TEM, FT-IR, and XPS analyses were conducted, and structural characterizations indicated that the CDs formed hydrogen bonding with B2O3. The temperature-dependent photoluminescence (PL) spectra demonstrated the existence of thermally activated delayed fluorescence in the composite. Further studies revealed that the B2O3 matrix restricted the vibration and rotation of CD chromophores and suppressed the non-radiative recombination of triplet excitons. Last but not least, potential applications in bioimaging, anti-counterfeiting, and information encryption were also explored. This work can provide new insights for developing metal-free and ultralong lifetime afterglow materials.

12.
World Neurosurg ; 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36682531

RESUMO

OBJECTIVE: Thirty-day readmission is one of the common complications after lumbar surgery. More thirty-day readmission increases the total hospitalization, economic burden and physical pain of patients, delays the progress of postoperative rehabilitation, and even lead to die. Therefore, it is necessary to analyze the risk factors of thirty-day readmission following lumbar surgery. METHODS: We searched for all the clinical trials published from the establishment of the database to May 1, 2022 through the Cochrane Library, Web of Science, Embase, and PubMed. Data including age, American Society of Anesthesiology physical status (ASA) class, preoperative hematocrit (Hct), diabetes mellitus (DM), current smoker, chronic obstructive pulmonary disease (COPD), length of hospital stay (LHS), operation time, and surgical site infection (SSI) were extracted. We used Review Manager 5.4 for data analysis. RESULTS: Six studies with 30989 participants were eligible for this meta-analysis. The analysis revealed that there were statistically significant differences in the age (95%CI: -3.35--2.90, p<0.001), preoperative Hct (95%CI: 0.75-1.33, p<0.001), DM (95%CI: 0.56-0.74, p<0.001), COPD (95%CI: 0.38-0.58, p<0.001), operation time (95%CI: -35.54--16.18, p<0.001), LHS (95%CI: -0.54--0.50, p<0.001), and SSI (95%CI: 0.02-0.03, p<0.001) between no readmission and readmission groups. In terms of the ASA and current smoker, there was no significant effect on the thirty-day readmission (p=0.16 and p=0.35 respectively). CONCLUSIONS: Age, preoperative Hct, DM, COPD, operation time, LHS, and SSI are the danger factors of thirty-day readmission following lumbar surgery.

13.
Microbiol Spectr ; : e0253022, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36651744

RESUMO

Central nervous system (CNS) infections can cause significant morbidity and mortality, especially in children. Rapid and accurate pathogenic detection in suspected CNS infections is essential for disease control at the early stage of infection. To evaluate the performance of metagenomic next-generation sequencing (mNGS) of cell-free DNA (cfDNA) in cerebrospinal fluid (CSF) in pediatric patients, we retrospectively analyzed the efficiency of cfDNA mNGS in children with CNS infections (n = 257) or noninfectious neurological disorders (n = 81). The CSF samples of 124 random subjects were used to evaluate the accuracy between mNGS of cfDNA and whole-cell DNA (wcDNA). In total, cfDNA mNGS detected a wide range of microbes with a detection rate of 71.0%, and the sensitivity and total coincidence rate with clinical diagnosis reached 68.9% and 67.5%, respectively. Compared with wcDNA mNGS, cfDNA mNGS had a higher efficacy in detecting viruses (66 versus 13) and Mycobacterium (7 versus 1), with significantly higher reads per million. The dominant causative pathogens were bacteria and viruses in CNS infections, but these presented with different pathogen spectra in different age categories. The best timing for the mNGS test ranged from 1 to 6 days after the start of anti-infection therapy, and the earlier mNGS started, the better was identification of bacterial CNS infections. This study emphasized that cfDNA mNGS had overall superiority to conventional methods on causative pathogen detection in pediatric CNS infections, and it was even better than wcDNA mNGS. Furthermore, research needs to be better validated in large-scale clinical trials to improve the clinical applications of cfDNA mNGS. IMPORTANCE Our study emphasized that cfDNA mNGS had overall superiority to conventional methods on causative pathogen detection in CNS-infected children, and it was even better than wcDNA mNGS. cfDNA mNGS detected a wide range of pathogens with a high total coincidence rate (67.5%) against clinical diagnosis. The best timing for cfDNA mNGS detection ranged from 1 to 6 days, rather than 0 days, after the start of empirical anti-infection therapy. The earlier mNGS started, the better the identifications of bacterial CNS infections. To the best of our knowledge, this research is the first report evaluating the clinical utility of mNGS with different methods (cfDNA versus wcDNA) of extracting DNA from CSF specimens in diagnosing pediatric CNS infections. Meanwhile, this is the largest cohort study that has evaluated the performance of mNGS using cfDNA from CSF specimens in pediatric patients with CNS infections.

14.
Pediatr Int ; : e15477, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36652421

RESUMO

BACKGROUND: The evidence that dynamic variables predict fluid responsiveness in young children is limited by conflicting results. METHODS: Sixty patients 1-3 years of age undergoing major neurosurgery received 10 ml/kg of Ringer's solution over 10 min after anesthesia induction. Aortic blood flow peak velocity (∆Vpeak), plethysmographic variability index (PVI), FloTrac/Vigileo-derived stroke volume variation (SVV), and dynamic arterial elastance (Eadyn ), and pulse pressure variation (PPV) were measured before and following fluid loading. An increase in cardiac index (CI) of ≥10% following fluid loading identified fluid "responders". RESULTS: Twenty-six (43.3%) patients were fluid responders. Baseline ∆Vpeak was an excellent predictor of a CI increase following fluid loading with an area under the receiver operating characteristic curve (AUROC) of 0.982 (P < 0.001). PVI showed fair diagnostic accuracy for CI-fluid responsiveness (AUROC 0.775, P < 0.001). Baseline ∆Vpeak and PVI cutoff values were 9.6% and 15%, respectively. PPV, SVV, and Eadyn were not or poor predictors for CI-fluid responsiveness (AUROC 0.669, 0.653, and 0.533, respectively). CONCLUSION: Volume-based PVI and ∆Vpeak showed acceptable reliabilities for fluid responsiveness prediction in young children undergoing major neurosurgery, while pressure-based SVV using FloTrac/Vigileo, Eadyn , and PPV not.

15.
Atherosclerosis ; 367: 1-7, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36706681

RESUMO

BACKGROUND AND AIMS: Risk stratification for three-vessel coronary artery disease (3VD) remains an important clinical challenge. In this study, we utilized machine learning (ML), which can address the limitations of traditional regression-based models, to develop a novel model to assess mortality risk in patients with 3VD. METHODS: This study was based on a prospective cohort of 8943 participants with 3VD consecutively enrolled between 2004 and 2011. An ML-derived random forest model was trained and tested to predict 4-year mortality. The predictability of the model was compared with that of an established model, the Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery score II (SSII), among 3VD patients undergoing percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), and medical therapy (MT) alone. RESULTS: The all-cause mortality was 7.5% (667 patients) over the 4-year follow-up period. The correlation-based feature selection algorithm selected 18 of the 94 features to develop the ML model. In the testing dataset, the ML-derived model achieved an area under the curve of 0.81 for 4-year mortality prediction. Its predictability was significantly better than that of the SSII among patients undergoing PCI (0.80 vs. 0.70, p < 0.001) or CABG (0.80 vs. 0.67, p < 0.001). The model also outperformed the SSII in patients receiving MT alone (ML: 0.75 vs. SSII for PCI: 0.70 or SSII for CABG: 0.66, p < 0.001). CONCLUSIONS: This ML-based approach exhibited better performance in risk stratification for 3VD compared with the conventional method. Further validation studies are needed to confirm these findings.

16.
Adv Healthc Mater ; : e2202814, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707970

RESUMO

Due to the safety issue and poor underwater adhesion of current commercially available bioadhesives, they are hard to apply to in vivo physiological environments and more diverse medical use conditions. In this study, a novel and facile bioadhesive for underwater medical applications was  designed based on the coacervation of electrostatic interactions and hydrophobic interactions, with the introduction of catechin (CC) as providers of catechol moieties for adhesion to surrounding tissues. The orange-colored bio-adhesive, named PcC, was  generated within seconds by mixing catechin-modified chondroitin sulfate (CSCC) and cholesterol chloroformate-modified polyethyleneimine (PEI-Chol) with agitation. In vitro mechanical measurements proved that this novel PcC bio-adhesive was  superior in underwater adhesion performance when applied to cartilage. Animal experiments in rat mastectomy model and rat cartilage graft implantation model have demonstrated its potential for diverse medical purposes, such as closing surgical incisions, reducing the formation of seroma, and tissue adhesive applied in orthopedic or cartilage surgery. This article is protected by copyright. All rights reserved.

17.
J Am Chem Soc ; 145(4): 2081-2087, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688920

RESUMO

Substantial advances in enantioconvergent C(sp3)-C(sp3) bond formations have been made with nickel-catalyzed cross-coupling of racemic alkyl electrophiles with organometallic reagents or nickel-hydride-catalyzed hydrocarbonation of alkenes. Herein, we report an unprecedented enantioselective C(sp3)-C(sp3) reductive cross-coupling by the direct utilization of two different alkyl halides with dual nickel/photoredox catalysis system. This highly selective coupling of racemic α-chloroboronates and unactivated alkyl iodides furnishes chiral secondary alkyl boronic esters, which serve as useful and important intermediates in the realm of organic synthesis and enable a desirable protocol to fast construction of enantioenriched complex molecules.

18.
J Am Chem Soc ; 145(4): 2690-2697, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36689463

RESUMO

Aliphatic alkylamines are abundant feedstock and versatile building blocks for many organic transformations. While remarkable progress has been made to construct C-N bonds on aliphatic and aromatic carbon centers, the activation and functionalization of C(sp3)-NH2 bonds in primary alkylamines remain a challenging process. In the present work, we discovered an unprecedented method to directly activate the C(sp3)-NH2 bond of primary alkylamines by a high-valent dinuclear CoIII,IV2(µ-O)2 diamond core complex. This reaction results in the installation of other functional groups such as halides and alkenes onto the α-carbon center concomitant with the 2-e- oxidation of the nitrogen atom on the amino group to form NH2OH. These results shed light on future development enabling versatile functionalization of primary alkylamines based on the dinuclear cobalt system. Moreover, our work suggests that a related high-valent copper-oxo intermediate is likely generated in the ammonia monooxygenase catalytic cycle to affect the oxidation of NH3 to NH2OH.

19.
Sci Rep ; 13(1): 1563, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709378

RESUMO

Temperature has an important influence on plant growth and development. In protected agriculture production, accurate prediction of temperature environment is of great significance. However, due to the time series, nonlinear and multi coupling characteristics of temperature, it is difficult to achieve accurate prediction. We proposed a method for building a solar greenhouse temperature prediction model based on a timeseries analysis, that considers the time series characteristics and dynamic temperature changes in the greenhouse system. The method would predict the temperature of greenhouse, and provide reference for the temperature change law in protected agriculture. A parameter analysis was performed on the nonlinear autoregressive exogenous (NARX) neural network, and a solar greenhouse temperature time series prediction model was established using the NARX regression neural network. The results showed that the proposed model depicted a maximum absolute error of 0.67 °C, and model correlation coefficient of 0.9996. Compared with the wavelet and BP neural networks, the NARX regression neural network accurately predicted and significantly outperformed in the solar greenhouse temperature prediction model. Moreover, the prediction model can accurately predict temperature trends within the solar greenhouse and is pivotal to obtaining precise control of solar greenhouse temperature.

20.
Mol Divers ; 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36705857

RESUMO

Earthworms are used to cure wounds in Chinese villages for thousands of years. Recently, scientists realized their extracts could promote wound healing and they have anti-inflammatory, antioxidant, anti-apoptosis, and anti-microbial properties, but its mechanism of promoting wound healing remains unclear. In the presented study, electronic literature databases and LC-MS/MS were used to determine earthworms' ingredients and differential metabolites. Swiss Target Prediction database was used for ingredients' target prediction and wound disease-relevant genes were found from GeneCards, OMIM, and DrugBank databases. Network pharmacology was conducted to demonstrate filtering hub targets, biological functions, and the signaling pathways of earthworms extract against wounds. Molecular docking and metabolism analysis were used to look for core target genes and key bioactive molecules from earthworms. Finally, the investigation shows 5 most important signal pathways, 5 core genes, and 6 bioactive ingredients-related cell-cell adhesion, cell proliferation, and cell migration processes could be affected by earthworms' extract. On 3rd day, the extract could regulate HIF1A and EGFR targets to make the differences of quantities of 4-pyridoxate, tetradecanoic acid, and L-kynurenine. While on 7th day, the regulation refers 6 earthworms' bioactive ingredients, 4 core genes (CTNNB1, EGFR, SRC, and CASP3), and 4 differential metabolites (4-hydoxy-2-quinolinecarboxylic acid, urocanate, deoxyinosine, creatine, and sn-glycerol-3-phosphocholine). on 14th day, 2 core genes (EGFR, SRC) are influenced in the biological processes. Briefly, we found that 6 ingredients from earthworms have most bioactive and 5 core genes play an important role in promoting wound-healing processes. These discovers indicates earthworms could against wound via AGE-RAGE, PI3K-Akt, HIF1A, MAPK, and Axon guidance pathways.

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