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1.
Artigo em Chinês | MEDLINE | ID: mdl-33794624

RESUMO

Objective:To assess and compare therapeutic effects and quality of life after endoscopic and microscopic myringoplasty using Chinese version of the Zurich chronic middle ear inventory(ZCMEI). Methods:Patients with chronic suppurative otitis media underwent myringoplasty at the Third Hospital of Peking University from October 2018 to September 2019 were included in this study and divided into two groups: endoscopic tympanoplasty group(n=40) and microscopic tympanoplasty group(n=57). ZCMEI survey and pure tone audiometry were conducted preoperatively and 3-9 months postoperatively. The operation time, intraoperative blood loss, length of hospital, graft success rate, complication rate, hearing improvement and quality of life improvement were compared. Results:①The operation time, length of hospital and intraoperative blood loss of endoscopic group were significantly lower(P<0.05). ②The graft success rate was 92.5% and 98.2%, respectively(P>0.05). The difference between the complication rate in two groups was not significant, but patients in endoscopic group had no symptoms of wound numbness or pain. ③Air conduction threshold(AC) and air-bone gap(ABG) were significantly lower after surgery in endoscopic group(n=33) and microscopic group(n=43). The analyzed result of generalized linear model indicated surgical approach had no influence on postoperative AC and ABG(P>0.05). ④The total scores of ZCMEI were significantly improved in endoscopic group(n=32) and microscopic group(n=48) postoperatively, as well as the scores of ear symptoms, hearing and psychosocial impact(P<0.05). Preoperative and postoperative scores of medical resources were not significantly different in either groups(P>0.05). Controlling the course of disease, the total ZCMEI results and scores of each subscale in patients with single ear involved(n=71) had no significant difference between two groups. Conclusion:Endoscopic myringoplasty has the advantages of minimal invasiveness, short operation time, and quick recovery evaluated from subjective and objective aspects. Audiometry improvement, graft success rate, complication rate and quality of life improvements are comparable between endoscopic tympanoplasty and conventional microscopic tympanoplasty. The assessment of the quality of life is of great significance in efficacy evaluation of otitis media. Doctors should comprehensively consider patient's subjective experience and the objective improvement to obtain the best clinical efficacy.


Assuntos
Miringoplastia , Qualidade de Vida , China , Doença Crônica , Orelha Média , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Timpanoplastia
2.
Biomed Chromatogr ; : e5140, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33830528

RESUMO

Due to the complexity of the composition of herbal and dietary supplement (HDS), it is a challenging problem to efficiently screen and identify active or toxic compounds. Psoralea corylifolia L. (PCL) is selected as the object to establish a methodology for rapid screening and identification of hepatotoxic compounds. High-content imaging and ultra-performance liquid chromatography and high-resolution mass spectrometry were used in this study to detect the hepatotoxicity and identified unknown compounds in PCL samples. Then, putative toxic compounds which are highly related to hepatotoxicity were screened by spectrum-toxicity correlation analysis, and verified the toxicity intensity by high-content imaging. The maximum non-toxic dose of processed samples with good detoxification effect reduced more than 9 times compared to unprocessed raw medicinal materials. Spectrum-toxicity correlation analysis showed that bavachinin A, bavachin, isobavachalcone, and neobavaisoflavone had high correlation with hepatotoxicity of PCL, and psoralen and isopsoralen had low correlation with the hepatotoxicity. This study verified the hepatotoxicity of this six putative compound monomers, proving the results of spectrum-toxicity correlation analysis. Based on the correlation analysis of high-resolution mass spectrometry of detection compounds and high-content imaging hepatocyte toxicity data, the potential toxic compound of HDS products can be quickly and accurately screened.

3.
BMC Psychol ; 9(1): 55, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33845895

RESUMO

BACKGROUND: Poor mental health status and associated risk factors of public health workers have been overlooked during the COVID-19 pandemic. This study used the effort-reward imbalance model to investigate the association between work-stress characteristics (effort, over-commitment, reward) and mental health problems (anxiety and depression) among front-line public health workers during the COVID-19 pandemic in China. METHODS: A total of 4850 valid online questionnaires were collected through a self- constructed sociodemographic questionnaire, the adapted ERI questionnaire, the 9-item Patient Health Questionnaire (PHQ-9) and the 7-item General Anxiety Disorder Scale (GAD-7). Hierarchical logistic regression analysis was conducted to investigate the association between ERI factors and mental health problems (i.e., depression and anxiety), with reward treated as a potential moderator in such associations. RESULTS: The data showed that effort and over-commitment were positively associated with depression and anxiety, while reward was negatively associated with depression and anxiety. Development and job acceptance were the two dimensions of reward buffered the harmful effect of effort/over-commitment on depression and anxiety, whereas esteem was non-significant. CONCLUSIONS: This study confirmed the harmful effects of effort and over-commitment on mental health among public health workers during the COVID-19 pandemic in China. Such effects could be alleviated through an appropriate reward system, especially the development and job acceptance dimensions of such a system. These findings highlight the importance of establishing an emergency reward system, comprising reasonable work-allocation mechanism, bonuses and honorary titles, a continuous education system and better career-development opportunities.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33822600

RESUMO

The tail spike of the mantis shrimp is the appendage for counteracting the enemy from behind. Here, we investigate the correlations between the chemical compositions, the microstructures, and the mechanical properties of the spike. We find that the spike is a hollow beam with a varying cross section along the length. The cross section comprises four different layers with distinct features of microstructures and chemical compositions. The local mechanical properties of these layers correlate well with the microstructures and chemical compositions, a combination of which effectively restricts the crack propagation while maximizing the release of strain energy during deformation. Finite element analysis and mechanics modeling demonstrate that the optimized structure of the spike confines the mechanical damage in the region near the tip and prevents catastrophic breakage at the base. Furthermore, we use a 3D printing technique to fabricate multiple hollow cylindrical samples consisting of biomimetic microstructures of the spike and confirm that the combination of the Bouligand structure with radially oriented parallel sheets greatly improves the toughness and strength during compression tests. The multiscale design strategy of the spike revealed here is expected to be of great interest for the development of novel bioinspired materials.

5.
J Ethnobiol Ethnomed ; 17(1): 25, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827630

RESUMO

BACKGROUND: As one of the oldest traditional dyes, people worldwide have used natural indigo for centuries. Local people have unique knowledge about indigo identification, which is crucial for indigo quality control and determining the dyeing effects. However, such traditional knowledge is rarely documented and explained. Therefore, the aims of this study were to document and assess the traditional knowledge used by local people when identifying natural indigo paste as well as quantitatively explore the characteristics and material basis of such traditional knowledge. METHOD: Three field surveys were conducted between 2019 and 2020. A total of 283 traditional indigo-paste artisans were interviewed in Guizhou, Yunnan, and Fujian Provinces. The frequency of citation, mention index, and fidelity level of each indigo-paste quality criterion were calculated to determine the most commonly used, recognized, and important quality criteria. To explore the characteristics and material basis of the traditional knowledge, we analyzed 21 indigo-paste samples using high-performance liquid chromatography with diode-array detection (HPLC-DAD), pH, and particle size analyses. RESULTS: Local people possess unique knowledge to identify natural indigo. Based on this knowledge accumulated over thousands of years, four criteria (color, taste, touch, and dyeing ability) were chosen by local people, and using these criteria, nature indigo was divided into five quality grades. The best quality indigo paste was judged according to the following folk criteria: dark blue in color with a purple-red luster; smooth and difficult to wipe off; having a sweet, bitter or spicy taste; and easy cloth dyeing. Additionally, the higher the contents of indigo and indirubin-especially indirubin-the better is the quality of the indigo paste. Within the pH range of 9-12, high-quality indigo-paste was more acidic. There was no significant relationship between particle size and quality. CONCLUSION: The ancient methods used by local people for identifying natural indigo are comprehensive and unique. By documenting the various folk quality criteria and conducting quantitative analyses, this study revealed the importance of indirubin and pH for assessing the quality of indigo paste. These findings differ from existing quality standards for synthetic indigo. Amid rapid modernization, traditional knowledge remains invaluable as a world heritage of humanity that warrants preservation.

6.
Bioelectrochemistry ; 140: 107804, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33813145

RESUMO

Alpha-fetoprotein (AFP) has become a specific tumor marker of primary liver cancer in clinical diagnosis. In this work, we prepared worm-like platinum (WL Pt) nanomaterial via chemical etching without organic solvents and ultra-high temperature. Due to its small particle size and the formation of surface vacancies during the etching process, it had a large specific surface area, and thus exhibited superior electrocatalytic activity for the reduction of hydrogen peroxide. Combining the signal amplification based on hydrogen peroxide reduction and the specific recognition of antigen with antibody, we constructed a simple label-free electrochemical immunosensor with a sandwich-like structure. The developed electrochemical immunosensor showed a wide linear range (0.0001-100 ng mL-1), a low detection limit (0.028 pg mL-1), good selectivity and stability. Further, the immunosensor was comparable with enzyme-linked immunosorbent assay (ELISA) and had a good accuracy for AFP detection in human serum samples proving the feasibility of potential application, which is expect to become one of the most promising method in early diagnosis and clinical analysis for liver cancer.

7.
Sci Rep ; 11(1): 7470, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33811251

RESUMO

AXIN1 mutations are observed in 8-10% of hepatocellular carcinomas (HCCs) and originally were considered to support tumor growth by aberrantly enhancing ß-catenin signaling. This view has however been challenged by reports showing neither a clear nuclear ß-catenin accumulation nor clearly enhanced expression of ß-catenin target genes. Here, using nine HCC lines, we show that AXIN1 mutation or siRNA mediated knockdown contributes to enhanced ß-catenin signaling in all AXIN1-mutant and non-mutant lines, also confirmed by reduced signaling in AXIN1-repaired SNU449 cells. Both AXIN1 and AXIN2 work synergistically to control ß-catenin signaling. While in the AXIN1-mutant lines, AXIN2 is solely responsible for keeping signaling in check, in the non-mutant lines both AXIN proteins contribute to ß-catenin regulation to varying levels. The AXIN proteins have gained substantial interest in cancer research for a second reason. Their activity in the ß-catenin destruction complex can be increased by tankyrase inhibitors, which thus may serve as a therapeutic option to reduce the growth of ß-catenin-dependent cancers. At concentrations that inhibit tankyrase activity, some lines (e.g. HepG2, SNU398) were clearly affected in colony formation, but in most cases apparently independent from effects on ß-catenin signaling. Overall, our analyses show that AXIN1 inactivation leads to enhanced ß-catenin signaling in HCC cell lines, questioning the strong statements that have been made in this regard. Enhancing AXIN activity by tankyrase monotherapy provides however no effective treatment to affect their growth exclusively through reducing ß-catenin signaling.

8.
Thorac Cancer ; 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33787090

RESUMO

Perioperative adjuvant treatment has become an increasingly important aspect of the management of patients with non-small cell lung cancer (NSCLC). In particular, the success of immune checkpoint inhibitors, such as antibodies against PD-1 and PD-L1, in patients with lung cancer has increased our expectations for the success of these therapeutics as neoadjuvant immunotherapy. Neoadjuvant therapy is widely used in patients with resectable stage IIIA NSCLC and can reduce primary tumor and lymph node stage, improve the complete resection rate, and eliminate microsatellite foci; however, complete pathological response is rare. Moreover, because the clinical benefit of neoadjuvant therapy is not obvious and may complicate surgery, it has not yet entered the mainstream of clinical treatment. Small-scale clinical studies performed in recent years have shown improvements in the major pathological remission rate after neoadjuvant therapy, suggesting that it will soon become an important part of NSCLC treatment. Nevertheless, neoadjuvant immunotherapy may be accompanied by serious adverse reactions that lead to delay or cancellation of surgery, additional illness, and even death, and have therefore attracted much attention. In this article, we draw on several sources of information, including (i) guidelines on adverse reactions related to immune checkpoint inhibitors, (ii) published data from large-scale clinical studies in thoracic surgery, and (iii) practical experience and published cases, to provide clinical recommendations on adverse events in NSCLC patients induced by perioperative immunotherapy.

9.
SLAS Technol ; : 24726303211000685, 2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33775155

RESUMO

This protocol focuses on the culture of cells harvested from hepatocellular carcinoma (HCC) patient-derived xenografts (PDXs) as organoids using a cellulosic macroporous sponge scaffold. Compared with many other epithelial cancer types, the viability of HCC cells directly derived from patients or PDX models is notoriously challenging to maintain in vitro. We previously developed a macroporous sponge scaffold uniquely designed to provide biochemical and mechanical cues that support the culture of normal hepatocytes as spheroids with maintained functionality. Leveraging our success using this sponge scaffold to maintain normal hepatocytes in vitro, we recently demonstrated that a similar sponge scaffold enables the maintenance of HCC PDX cells as organoids with preserved viability, molecular features, and heterogeneity.

10.
Aging Cell ; : e13353, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33780118

RESUMO

MicroRNAs (miRNAs) regulate gene expression and thereby influence cell development and function. Numerous studies have shown the significant roles of miRNAs in regulating immune cells including natural killer (NK) cells. However, little is known about the role of miRNAs in NK cells with aging. We previously demonstrated that the aged C57BL/6 mice have significantly decreased proportion of mature (CD27- CD11b+ ) NK cells compared with young mice, indicating impaired maturation of NK cells with aging. Here, we performed deep sequencing of CD27+ NK cells from young and aged mice. Profiling of the miRNome (global miRNA expression levels) revealed that 49 miRNAs displayed a twofold or greater difference in expression between young and aged NK cells. Among these, 30 miRNAs were upregulated and 19 miRNAs were downregulated in the aged NK cells. We found that the expression level of miR-l8la-5p was increased with the maturation of NK cells, and significantly decreased in NK cells from the aged mice. Knockdown of miR-181a-5p inhibited NK cell development in vitro and in vivo. Furthermore, miR-181a-5p is highly conserved in mice and human. MiR-181a-5p promoted the production of IFN-γ and cytotoxicity in stimulated NK cells from both mice and human. Importantly, miR-181a-5p level markedly decreased in NK cells from PBMC of elderly people. Thus, our results demonstrated that the miRNAs profiles in NK cells change with aging, the decreased level of miR-181a-5p contributes to the defective NK cell development and function with aging. This opens new strategies to preserve or restore NK cell function in the elderly.

11.
Anal Chim Acta ; 1154: 338310, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736798

RESUMO

Novel coronavirus disease (COVID-19) caused by SARS-CoV-2 is an ongoing global pandemic associated with high rates of morbidity and mortality. RT-qPCR has become the diagnostic standard for the testing of SARS-CoV-2 in most countries. COVID-19 diagnosis generally relies upon RT-qPCR-mediated identification of SARS-CoV-2 viral RNA, which is costly, labor-extensive, and requires specialized training and equipment. Herein, we established a novel one-tube rapid diagnostic approach based upon formamide and colorimetric RT-LAMP (One-Pot RT-LAMP) that can be used to diagnose COVID-19 without the extraction of specific viral RNA. The technique could visually detect SARS-CoV-2 within 45 min with a limit of detection of 5 copies per reaction in extracted RNA, and about 7.66 virus copies per µL in viral transport medium. The One-Pot RT-LAMP test showed a high specificity without cross-reactivity with 12 viruses including SARS-CoV, MERS-CoV, and human infectious influenza virus (H1N1/H3N2 of influenza A and B virus, ect. We validated this One-Pot RT-LAMP approach by its successful use for the analysis of 45 clinical nasopharyngeal swab samples, yielding results identical to those of traditional RT-qPCR analyses, while achieving good selectivity and sensitivity relative to a commercial RT-qPCR approach. As such, this One-Pot RT-LAMP technology may be a valid means of conducting high-sensitivity, low-cost and rapid SARS-CoV-2 identification without the extraction of viral RNA.


Assuntos
/métodos , /diagnóstico , /virologia , Primers do DNA/química , Primers do DNA/metabolismo , Humanos , Limite de Detecção , Técnicas de Diagnóstico Molecular , Nasofaringe/virologia , Técnicas de Amplificação de Ácido Nucleico , RNA Viral/análise , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , /isolamento & purificação , Fatores de Tempo
12.
Behav Processes ; 186: 104372, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33667486

RESUMO

Research suggests that predation risk during adolescence can program adult stress response and emotional behavior; however, little is known about the short-term and lasting residual effects of this experience on social behavior. We explored this concept in social Brandt's voles (Lasiopodomys brandtii). Adolescent male and female voles were exposed to distilled water, rabbit urine (as a non-predator stimulus), and cat urine for 60 min daily from postnatal day (PND) 28-49. Social play tests were conducted immediately following exposure on PND 28, 35, 42, and 49. In the social play test, repeated cat odor (CO) exposure enhanced the contact behavior of voles with their cagemate. Adolescent exposure to CO did not affect behavioral responses toward unrelated pups in the alloparental behavior test or same-sex individuals in the social interaction test. However, exposure to CO significantly enhanced the licking/grooming behavior of voles towards their own pups in the home cage parental behavior test. Repeated CO exposure significantly inhibited weight gain in male voles during adolescence. This effect was transmitted to the next generation, with lower weight gain in offspring before weaning. Following repeated CO exposure, males tended to have more female offspring whereas females produced more offspring, suggesting an adaptive strategy to increase inclusive fitness under predatory risk. These findings demonstrate that adolescent exposure to predatory risk augments adolescent social contact and adult parental behavior and suggest a role for improved inclusive fitness in mediating long-term outcomes.

13.
J Alzheimers Dis ; 80(3): 1311-1327, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33682707

RESUMO

BACKGROUND: The volume loss of the hippocampus and amygdala in non-demented individuals has been reported to increase the risk of developing Alzheimer's disease (AD). Many neuroimaging genetics studies mainly focused on the individual effects of APOE and CLU on neuroimaging to understand their neural mechanisms, whereas their synergistic effects have been rarely studied. OBJECTIVE: To assess whether APOE and CLU have synergetic effects, we investigated the epistatic interaction and combined effects of the two genetic variants on morphological degeneration of hippocampus and amygdala in the non-demented elderly at baseline and 2-year follow-up. METHODS: Besides the widely-used volume indicator, the surface-based morphometry method was also adopted in this study to evaluate shape alterations. RESULTS: Our results showed a synergistic effect of homozygosity for the CLU risk allele C in rs11136000 and APOEɛ4 on the hippocampal and amygdalar volumes during a 2-year follow-up. Moreover, the combined effects of APOEɛ4 and CLU C were stronger than either of the individual effects in the atrophy progress of the amygdala. CONCLUSION: These findings indicate that brain morphological changes are caused by more than one gene variant, which may help us to better understand the complex endogenous mechanism of AD.

14.
Medicine (Baltimore) ; 100(13): e25194, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33787601

RESUMO

BACKGROUND: This study aimed to explore the clinical characteristics, therapeutic efficacy and prognostic factors of peripheral T-cell lymphoma (PTCL). METHODS: The clinical data of 119 PTCL patients who were admitted to the Xinjiang Medical University Affiliated Tumor Hospital from January 2010 to December 2017 were retrospectively analyzed, including the clinical characteristics, therapeutic efficacy, prognosis-related factors and treatments. Among the patients, 98 patients received antharcyclines-based therapeutic protocols, including Cyclophosphamide, Pirarubicin, Vincristine, Prednisone (CHOP) protocol and Cyclophosphamide, Pirarubicin, Vincristine, Prednisone, Etoposide (CHOPE) protocol, with median follow-up time of 32.5 months (2-166 months). The patients' clinical characteristics were analyzed, and COX ratio risk regression model was adopted to analyze the prognostic factors related with the survival rate of PTCL patients. RESULTS: The 5-year overall survival (OS) rate was 46.4% and progression-free survival (PFS) rate was 42.7% in the 98 patients, and there were insignificant differences between patients with CHOP protocol and those with CHOPE protocol in the 5-year OS and PFS rates (OS: P = 0.197, PFS: P = 0.663). The univariate analysis results showed that different pathological types, Ann Arbor stage, Eastern Cooperative Oncology Group (ECOG) score ≥ 2, the number of extranodal lymphomas involved, Lactic dehydrogenase (LDH) level, presence/absence of bone marrow involved, international prognostic index (IPI) score, ß2 microglobulin (ß2-MG) level and hemoglobin (Hb) level were poor prognosis factors influencing patients' OS and PFS rates (P all < .05). Multivariate analysis demonstrated that different pathological types, Ann Arbor stage, presence/absence of bone marrow involved and Hb level were independent prognostic indicators influencing patients' OS and PFS rates (P all < .05). CONCLUSION: PTCL is poor in therapeutic efficacy and prognosis, and different pathological types, Ann Arbor stage, presence/absence of bone marrow involved and Hb level are related with the prognosis of PTCL patients. Anemia occurring before the treatment is an important predictive indicator influencing the prognosis of PTCL patients and patients who experience anemia will be poor in prognosis.

15.
Explore (NY) ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33712360

RESUMO

The main clinical manifestations of pleural effusion are exertional dyspnea, predominantly dry cough, and pleuritic chest pain. To treat pleural effusion appropriately, it is important to determine its etiology; which however, remains unclear in nearly 20% of cases.A 73-year-old man with a history of invasive pulmonary tuberculosis (TB), had been experiencing chest congestion and dyspnea with undiagnosed pleural effusion for six years. After a series of clinical examination and laboratory tests, there was still no clear diagnosis. Despite administering diuretics and intermittent draining, the patient's condition aggravated progressively. He sought further treatment at Dongzhimen Hospital Respiratory Outpatient Clinic. The patient was treated with Zanthoxylum and Trichosanthes Decoction (Jiao Mu Gua Lou Tang). After one and a half years, his symptoms greatly improved and ultrasound revealed that the pleural effusion had apparently absorbed.It is suggested that TCM herbal formulas can play a critical role in preventing the progression of complicated, undiagnosed pleural effusion, especially in cases of poor response to conventional therapy and thoracentesis. Additional studies on the functions and mechanisms of the medicinals are warranted.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33712426

RESUMO

Selective oxidation of C-H bonds in alkylphenols holds great significance for not only structural derivatization in pharma- and bio-manufacturing but also biological degradation of these toxic chemicals in environmental protection. A unique chemomimetic biocatalytic system using enzymes from a p-cresol biodegradation pathway has recently been developed. As the central biocatalyst, the cytochrome P450 monooxygenase CreJ oxidizes diverse p- and m-alkylphenyl phosphates with perfect stereoselectivity at different efficiencies. However, the mechanism of regio- and stereoselectivity of this chemomimetic biocatalytic system remained unclear. Here, using p- and m-ethylphenyl substrates, we elucidate the CreJ-catalyzed key steps for selective oxidations. The crystal structure of CreJ in complex with m-ethylphenyl phosphate was solved and compared with its complex structure with p-ethylphenyl phosphate isomer. The results indicate that the conformational changes of substrate-binding residues are slight, while the substrate promiscuity is achieved mainly by the available space in the catalytic cavity. Moreover, the catalytic preferences of regio- and stereoselective hydroxylation for the two ethylphenyl substrates is explored by molecular dynamics simulations. The ethyl groups in the complexes display different flexibility, and the distances of the active oxygen to H pro-S and H pro-R of methylene agree with the experimental stereoselectivity. The regioselectivity can be explained by the distances and bond dissociation energy. These results provide not only the mechanistic insights of CreJ into its regio- and stereoselectivity but also the structural basis for further P450 enzyme design and engineering.ImportanceThe key cytochrome P450 monooxygenase CreJ showed excellent regio- and stereoselectivity in the oxidation of various alkylphenol substrates. C-H bond functionalization of these toxic alkylphenols holds great significance both for biological degradation of these environmental chemicals and production of value-added structural derivatives in pharmaceutical and biochemical industries. Our results, combined with in vitro enzymatic assays, crystal structure determination of enzyme-substrate complex, and molecular dynamics simulations, provide not only significant mechanism elucidation of the regio- and stereoselective catalyzation mediated by CreJ, but also the promising directions for the future engineering efforts of this enzyme towards more useful products. It also has great extendable potentials to couple this multifunctional P450 biocatalyst with other post modifying enzymes (e.g. hydroxyl based glycosylase) to access more alkylphenol derived high-value chemicals through environment-friendly biocatalysis and biotransformation.

17.
PLoS One ; 16(3): e0248273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33725000

RESUMO

The COVID-19 outbreak on the Diamond Princess (DP) cruise ship has provided empirical data to study the transmission potential of COVID-19 with the presence of pre/asymptomatic cases. We studied the changes in R0 on DP from January 21 to February 19, 2020 based on chain binomial models under two scenarios: no quarantine assuming a random mixing condition, and quarantine of passengers in cabins-passengers may get infected either by an infectious case in a shared cabin or by pre/asymptomatic crew who continued to work. Estimates of R0 at the beginning of the epidemic were 3.27 (95% CI, 3.02-3.54) and 3.78 (95% CI, 3.49-4.09) respectively for serial intervals of 5 and 6 days; and when quarantine started, with the reported asymptomatic ratio 0.505, R0 rose to 4.18 (95%CI, 3.86-4.52) and 4.73 (95%CI, 4.37-5.12) respectively for passengers who might be exposed to the virus due to pre/asymptomatic crew. Results confirm that the higher the asymptomatic ratio is, the more infectious contacts would happen. We find evidence to support a US CDC report that "a high proportion of asymptomatic infections could partially explain the high attack rate among cruise ship passengers and crew." Our study suggests that if the asymptomatic ratio is high, the conventional quarantine procedure may not be effective to stop the spread of virus.


Assuntos
Infecções Assintomáticas/epidemiologia , Modelos Estatísticos , /epidemiologia , /virologia , Surtos de Doenças , Humanos , Quarentena , Navios
18.
Neurotox Res ; 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33770366

RESUMO

Nitrous oxide (N2O), also known as "laughing gas," is a colorless, nonirritating gas. Clinically, it is widely used as an inhaled anesthetic, analgesic, and anxiolytic. In recent years, recreational abuse of N2O has become increasingly common, especially among young adults and adolescents, but many of them lack awareness of the possible side effects associated with this drug. N2O abuse can damage multiple systems, especially the nervous system, but the exact mechanism of N2O toxicity remains controversial. At present, an increasing number of cases of nervous system damage caused by N2O abuse have been reported both at home and abroad. Discontinuation of N2O use and timely supplementation with vitamin B12 are essential for a good prognosis. Long-term abuse without timely treatment will eventually lead to irreversible neurological damage. In this article, we discuss the epidemiology of N2O abuse, neurotoxicity mechanisms, clinical manifestations, relevant auxiliary examinations, treatments, and prognosis to improve social awareness of N2O exposure risk, especially among users and clinicians.

19.
Neurosci Lett ; 752: 135842, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33766734

RESUMO

BACKGROUND: Numerous publications have demonstrated that melatonin administration is associated with mortality reduction and improvement in neurological outcomes after traumatic brain injury (TBI). However, there are significant sex differences in several diseases associated with melatonin. We aimed to determine whether androgen was responsible for enhanced susceptibility of melatonin against TBI in females, as well as potential molecular mechanisms. METHODS: Weight-drop was used to establish a rodent model of TBI. Melatonin (10 mg/kg) and testosterone (1 mg/kg) were administered three times every day for three days after TBI using subcutaneous injection, respectively. Seven days after TBI, an open field assay was used to evaluate locomotor and exploratory activities. Neuronal amount, neuronal apoptosis, and expression of phosphorylated extracellularly regulated protein kinases 1/2 (ERK1/2), c-jun N-terminal kinase 1/2 (JNK1/2), and p38 mitogen-activated protein kinase (p38MAPK) in neurons were assessed using immunofluorescence assay seven days after TBI. The expression of caspase-3, Bax, and Bcl-2 in the frontal cortex was detected using western blot. RESULTS: Compared with female rats, melatonin administration exhibited more neuroprotective effects (including improved locomotor and exploratory activities, elevated neuronal amount, and reduced neuronal apoptosis) in male rats exposed to TBI. Moreover, testosterone significantly improved locomotor and exploratory activities, elevated neuronal amount, decreased neuronal apoptosis, downregulated phosphorylation of JNK1/2- and p38MAPK-positive neurons, but upregulated phosphorylation of ERK1/2-positive neurons in the frontal cortex, and reduced the expressions of cleaved caspase-3, Bax, but increased Bcl-2 expressions in female rats exposed to TBI. CONCLUSIONS: Androgen was responsible for the enhanced susceptibility to TBI under melatonin supplementation in females through a mechanism that may be associated with MAPK pathway regulation.

20.
BMC Musculoskelet Disord ; 22(1): 236, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648479

RESUMO

BACKGROUND: Recently, a percutaneous spinal endoscopy unilateral posterior interlaminar approach to perform bilateral decompression has been proposed for use in treatment of lumbar spinal stenosis, As a development and supplement to traditional surgery, its advantages regarding therapeutic effects and prognosis, such as minor soft tissue damage, little intraoperative blood loss, and a quick return to daily life. However, there are few analyses of this surgery with a follow-up of more than 1 year,we conducted this study in order to quantitatively investigate radiographic and clinical efficacies of this surgery for central lumbar spinal stenosis. MATERIALS AND METHODS: Forty-six patients with central lumbar spinal stenosis were enrolled from January 2017 to July 2018. The visual analog scale (VAS) for back pain and leg pain, Oswestry disability index (ODI), modified MacNab criteria were used to evaluate clinical efficiency at preoperative and postoperative time points. The intervertebral height index (IHI), cross-sectional area of the spinal canal (CSAC), calibrated disc signal (CDS) and spinal stability were examined to assess radiographic decompression efficiency via magnetic resonance imaging and X-ray at preoperative and postoperative time points. RESULTS: The VAS score for lower back pain and leg pain improved from 7.50 ± 0.78 to 1.70 ± 0.66 and from 7.30 ± 0.79 to 1.74 ± 0.68, respectively, and the ODI improved from 72.35 ± 8.15 to 16.15 ± 4.51. In terms of modified MacNab criteria, 91.3% of the patients achieved good or excellent outcomes. Furthermore, significant changes after surgery were observed for the percentage of CSAC, increasing from 125.3 ± 53.9 to 201.4 ± 78 mm2; however, no significant differences were observed for the remaining measurement indicators. CONCLUSIONS: The clinical and radiographic efficacies of this surgery for central lumbar spinal stenosis were good in short-term follow-up, and this surgery did not cause meaningful changes in IHI, CDS, and spine stability in short-term follow-up. The effect of long-term follow-up needs further investigation.

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