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1.
Nature ; 579(7798): 270-273, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32015507

RESUMO

Since the outbreak of severe acute respiratory syndrome (SARS) 18 years ago, a large number of SARS-related coronaviruses (SARSr-CoVs) have been discovered in their natural reservoir host, bats1-4. Previous studies have shown that some bat SARSr-CoVs have the potential to infect humans5-7. Here we report the identification and characterization of a new coronavirus (2019-nCoV), which caused an epidemic of acute respiratory syndrome in humans in Wuhan, China. The epidemic, which started on 12 December 2019, had caused 2,794 laboratory-confirmed infections including 80 deaths by 26 January 2020. Full-length genome sequences were obtained from five patients at an early stage of the outbreak. The sequences are almost identical and share 79.6% sequence identity to SARS-CoV. Furthermore, we show that 2019-nCoV is 96% identical at the whole-genome level to a bat coronavirus. Pairwise protein sequence analysis of seven conserved non-structural proteins domains show that this virus belongs to the species of SARSr-CoV. In addition, 2019-nCoV virus isolated from the bronchoalveolar lavage fluid of a critically ill patient could be neutralized by sera from several patients. Notably, we confirmed that 2019-nCoV uses the same cell entry receptor-angiotensin converting enzyme II (ACE2)-as SARS-CoV.


Assuntos
Betacoronavirus/classificação , Betacoronavirus/genética , Quirópteros/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Antivirais/sangue , Betacoronavirus/metabolismo , Betacoronavirus/ultraestrutura , COVID-19 , Linhagem Celular , China/epidemiologia , Chlorocebus aethiops , Feminino , Genoma Viral/genética , Humanos , Masculino , Peptidil Dipeptidase A/metabolismo , Filogenia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/classificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2 , Homologia de Sequência do Ácido Nucleico , Síndrome Respiratória Aguda Grave , Células Vero
2.
Eur J Nucl Med Mol Imaging ; 51(2): 455-467, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37801139

RESUMO

PURPOSE: Despite the revealed role of immunological dysfunctions in the development and progression of Alzheimer's disease (AD) through animal and postmortem investigations, direct evidence regarding the impact of genetic factors on microglia response and amyloid-ß (Aß) deposition in AD individuals is lacking. This study aims to elucidate this mechanism by integrating transcriptomics and TSPO, Aß PET imaging in clinical AD cohort. METHODS: We analyzed 85 patients with PET/MR imaging for microglial activation (TSPO, [18F]DPA-714) and Aß ([18F]AV-45) within the prospective Alzheimer's Disease Immunization and Microbiota Initiative Study Cohort (ADIMIC). Immune-related differentially expressed genes (IREDGs), identified based on AlzData, were screened and verified using blood samples from ADIMIC. Correlation and mediation analyses were applied to investigate the relationships between immune-related genes expression, TSPO and Aß PET imaging. RESULTS: TSPO uptake increased significantly both in aMCI (P < 0.05) and AD participants (P < 0.01) and showed a positive correlation with Aß deposition (r = 0.42, P < 0.001). Decreased expression of TGFBR3, FABP3, CXCR4 and CD200 was observed in AD group. CD200 expression was significantly negatively associated with TSPO PET uptake (r =-0.33, P = 0.013). Mediation analysis indicated that CD200 acted as a significant mediator between TSPO uptake and Aß deposition (total effect B = 1.92, P = 0.004) and MMSE score (total effect B =-54.01, P = 0.003). CONCLUSION: By integrating transcriptomics and TSPO PET imaging in the same clinical AD cohort, this study revealed CD200 played an important role in regulating neuroinflammation, Aß deposition and cognitive dysfunction.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Perfilação da Expressão Gênica , Doenças Neuroinflamatórias , Tomografia por Emissão de Pósitrons/métodos , Estudos Prospectivos , Receptores de GABA/genética , Receptores de GABA/metabolismo
3.
Brain Behav Immun ; 119: 14-27, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38548184

RESUMO

BACKGROUND: Alzheimer's disease (AD), the most prevalent type of dementia, still lacks disease-modifying treatment strategies. Recent evidence indicates that maintaining gut microbiota homeostasis plays a crucial role in AD. Targeted regulation of gut microbiota, including probiotics, is anticipated to emerge as a potential approach for AD treatment. However, the efficacy and mechanism of multi-strain probiotics treatment in AD remain unclear. METHODS: In this study, 6-month-old senescence-accelerated-mouse-prone 8 (SAMP8) and senescence-accelerated-mouse-resistant 1 (SAMR1) were utilized. The SAMP8 mice were treated with probiotic-2 (P2, a probiotic mixture of Bifidobacterium lactis and Lactobacillus rhamnosus) and probiotic-3 (P3, a probiotic mixture of Bifidobacterium lactis, Lactobacillus acidophilus, and Lactobacillus rhamnosus) (1 × 109 colony-forming units) once daily for 8 weeks. Morris water maze (MWM) and novel object recognition (NOR) tests were employed to assess the memory ability. 16S sequencing was applied to determine the composition of gut microbiota, along with detecting serum short-chain fatty acids (SCFAs) concentrations. Neural injury, Aß and Tau pathology, and neuroinflammation level were assessed through western blot and immunofluorescence. Finally, potential molecular mechanisms was explored through transcriptomic analysis and western blotting. RESULTS: The MWM and NOR test results indicated a significant improvement in the cognitive level of SAMP8 mice treated with P2 and P3 probiotics compared to the SAMP8 control group. Fecal 16S sequencing revealed an evident difference in the α diversity index between SAMP8 and SAMR1 mice, while the α diversity of SAMP8 mice remained unchanged after P2 and P3 treatment. At the genus level, the relative abundance of ten bacteria differed significantly among the four groups. Multi-strain probiotics treatment could modulate serum SCFAs (valeric acid, isovaleric acid, and hexanoic acid) concentration. Neuropathological results demonstrated a substantial decrease in neural injury, Aß and Tau pathology and neuroinflammation in the brain of SAMP8 mice treated with P3 and P2. Transcriptomic analysis identified the chemokine signaling pathway as the most significantly enriched signaling pathway between SAMP8 and SAMR1 mice. Western blot test indicated a significant change in the phosphorylation level of downstream AKT/GSK-3ß between the SAMP8 and SAMR1 groups, which could be reversed through P2 and P3 treatment. CONCLUSIONS: Multi-strain probiotics treatment can ameliorate cognitive impairment and pathological change in SAMP8 mice, including neural damage, Aß and Tau pathology, and neuroinflammation. This effect is associated with the regulation of the phosphorylation of the AKT/GSK-3ß pathway.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Modelos Animais de Doenças , Microbioma Gastrointestinal , Glicogênio Sintase Quinase 3 beta , Probióticos , Proteínas Proto-Oncogênicas c-akt , Animais , Probióticos/farmacologia , Probióticos/uso terapêutico , Camundongos , Doença de Alzheimer/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Disfunção Cognitiva/metabolismo , Masculino , Envelhecimento/metabolismo , Transdução de Sinais/efeitos dos fármacos , Lacticaseibacillus rhamnosus , Proteínas tau/metabolismo
4.
Physiol Plant ; 176(2): e14243, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38467539

RESUMO

Seed priming with beneficial endophytic fungi is an emerging sustainable strategy for enhancing plant resistance against insect pests. This study examined the effects of Beauvaria bassiana Bb20091317 and Metarhizium rileyi MrCDTLJ1 fungal colonization on maize growth, defence signalling, benzoxazinoid levels and gene expression. The colonization did not adversely affect plant growth but reduced larval weights of Spodoptera frugiperda. Maize leaves treated with M. rileyi exhibited higher levels of jasmonic acid, jasmonoyl-Isoleucine, salicylic acid, and indole acetic acid compared to control. B. bassiana and M. rileyi accelerated phytohormone increase upon S. frugiperda herbivory. Gene expression analysis revealed modulation of benzoxazinoid biosynthesis genes. We further elucidated the immune regulatory role of the transcription factor zmWRKY36 using virus-induced gene silencing (VIGS) in maize. zmWRKY36 positively regulates maize immunity against S. frugiperda, likely by interacting with defense-related proteins. Transient overexpression of zmWRKY36 in tobacco-induced cell death, while silencing in maize reduced chitin-triggered reactive oxygen species burst, confirming its immune function. Overall, B. bassiana and M. rileyi successfully colonized maize, impacting larval growth, defense signalling, and zmWRKY36-mediated resistance. This sheds light on maize-endophyte-insect interactions for sustainable plant protection.


Assuntos
Benzoxazinas , Zea mays , Animais , Spodoptera/fisiologia , Zea mays/genética , Zea mays/metabolismo , Benzoxazinas/metabolismo , Benzoxazinas/farmacologia , Herbivoria , Larva/fisiologia , Fungos
5.
Phys Chem Chem Phys ; 26(15): 11570-11581, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38533820

RESUMO

The capture and separation of CF4 from CF4/N2 mixture gas is a crucial issue in the electronics industry, as CF4 is a commonly used etching gas and the ratio of CF4 to N2 directly affects process efficiency. Utilizing high-throughput computational screening techniques and grand canonical Monte Carlo (GCMC) simulations, we comprehensively screened and assessed 247 types of pure silicon zeolite materials to determine their adsorption and separation performance for CF4/N2 mixtures. Based on screening, the relationships between the structural parameters and adsorption and separation properties were meticulously investigated. Four indicators including adsorption selectivity, working capacity, adsorbent performance score (APS), and regenerability (R%) were used to evaluate the performance of adsorbents. Based on the evaluation, we selected the top three best-performing zeolite structures for vacuum swing adsorption (LEV, AWW and ESV) and pressure swing adsorption (AVL, ZON, and ERI) processes respectively. Also, we studied the preferable adsorption sites of CF4 and N2 in the selected zeolite structures through centroid density distributions at the molecule level. We expect the study may provide some valuable guidance for subsequent experimental investigations on adsorption and separation of CF4/N2.

6.
J Integr Plant Biol ; 66(2): 285-299, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38314502

RESUMO

Roots are fundamental for plants to adapt to variable environmental conditions. The development of a robust root system is orchestrated by numerous genetic determinants and, among them, the MADS-box gene ANR1 has garnered substantial attention. Prior research has demonstrated that, in chrysanthemum, CmANR1 positively regulates root system development. Nevertheless, the upstream regulators involved in the CmANR1-mediated regulation of root development remain unidentified. In this study, we successfully identified bric-a-brac, tramtrack and broad (BTB) and transcription adapter putative zinc finger (TAZ) domain protein CmBT1 as the interacting partner of CmANR1 through a yeast-two-hybrid (Y2H) screening library. Furthermore, we validated this physical interaction through bimolecular fluorescence complementation and pull-down assays. Functional assays revealed that CmBT1 exerted a negative influence on root development in chrysanthemum. In both in vitro and in vivo assays, it was evident that CmBT1 mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome pathway. This ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2, which was crucial for root development in chrysanthemum. Genetic analysis suggested that CmBT1 modulated root development, at least in part, by regulating the level of CmANR1 protein. Collectively, these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination, thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.


Assuntos
Chrysanthemum , Chrysanthemum/genética , Chrysanthemum/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitinação , Ligação Proteica , Dedos de Zinco , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
7.
J Oncol Pharm Pract ; : 10781552231216104, 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38043937

RESUMO

INTRODUCTION: Immune checkpoint inhibitors can cause immune-related toxicity in various systems, with myocarditis being the most severe and life-threatening manifestation. This report presents a case in which myocarditis developed following administration of programmed cell death protein-1 (PD-1) inhibitors therapy. We describe the diagnosis and treatment of this patient in detail. CASE REPORT: We present the case of a 59-year-old female diagnosed with post-operative esophageal cancer and hepatic metastases. The patient underwent second-line treatment with domestically-made PD-1 inhibitor, camrelizumab, in combination with paclitaxel (albumin-bound) and carboplatin for two cycles. During the course of treatment, an electrocardiogram (ECG) revealed ST segment elevation in leads II, III, aVF, V2, V3, and V4, along with T wave changes in leads I and aVL. Laboratory examinations showed abnormal levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT). Despite the absence of clinical symptoms, the patient was routinely hospitalized three weeks later. Based on the findings from the ECG, cardiac biomarkers, echocardiography, echocardiogram, cardiac magnetic resonance, and angiography, she was diagnosed with immune-checkpoint-inhibitors-related myocarditis. MANAGEMENT AND OUTCOME: The patient received immunoglobulin (0.5 g/kg/day) and was initially given methylprednisolone (1000 mg/day). Methylprednisolone was gradually reduced to 40 mg/day in 2 weeks. During this time, the levels of biomarkers indicative of myocardial injury also exhibited a simultaneous decline. DISCUSSION: This case highlights the importance of early detection and prompt intervention, including initiating appropriate steroid therapy and discontinuing of immune checkpoint inhibitors. Such measures can effectively prevent morbidity and mortality, ultimately leading to an improved prognosis.

8.
Ecotoxicol Environ Saf ; 249: 114354, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508833

RESUMO

BACKGROUND AND OBJECTIVES: Studies on the effects of airborne particulates of diameter ≤ 1 µm (PM1), airborne particulates of diameter ≤ 2.5 µm (PM2.5) and airborne particulates of diameter ranges from 1 to 2.5 µm (PM1-2.5) on incidence of hyperuricemia are limited. We aimed to investigate the associations between PM1, PM2.5, and PM1-2.5 and hyperuricemia among male traffic officers. METHODS: We conducted a prospective cohort study of 1460 traffic officers without hyperuricemia in Guangzhou, China from 2009 to 2016. Exposures of PM1 and PM2.5 were estimated with a spatiotemporal model. PM1-2.5 concentrations were calculated by subtracting PM1 from PM2.5 concentrations. Cox's proportional hazards regressions models were used to examine the association between PM1, PM2.5, and PM1-2.5 and hyperuricemia, adjusted for potential confounders. Associations between PM1, PM2.5, and PM1-2.5 and serum uric acid (SUA) levels were evaluated with multiple linear regression models. RESULTS: Hazard ratios (HRs) and 95% confidence intervals (CIs) of hyperuricemia associated with 10 µg/m3 increment in PM1, PM2.5, and PM1-2.5 were 1.67 (95% CI:1.30-2.36), 1.49 (95% CI: 1.27-1.75), and 2.18 (95% CI: 1.58-3.02), respectively. The SUA concentrations increased by 12.23 µmol/L (95% CI: 5.91-18.56), 6.93 µmol/L (95% CI: 3.02-10.84), and 8.72 µmol/L (95% CI: 0.76-16.68) per 10 µg/m3 increase in PM1, PM2.5, and PM1-2.5, respectively. Stratified analyses indicated the positive associations of PM2.5 and PM1-2.5 with SUA levels were stronger in non-smokers, and PM1, PM2.5, and PM1-2.5 with SUA levels were stronger in non-drinkers. CONCLUSION: Long-term PM1, PM2.5, and PM1-2.5 exposures may increase the risk of hyperuricemia and elevate SUA levels among male traffic officers, especially in non-smokers and non-drinkers.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hiperuricemia , Humanos , Masculino , Material Particulado/toxicidade , Material Particulado/análise , Poluentes Atmosféricos/análise , Hiperuricemia/epidemiologia , Estudos Prospectivos , Ácido Úrico/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , China/epidemiologia , Poluição do Ar/análise
9.
J Clin Ultrasound ; 51(7): 1212-1222, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37334435

RESUMO

AIMS: To investigate the reliability, validity, and level of evidence of applying ultrasound in assessing the lower-limb muscles of patients with cerebral palsy (CP). METHOD: Publications in Medline, PubMed, Web of Science, and Embase were searched on May 10, 2023, to identify and examine relevant studies investigating the reliability/validity of ultrasound in evaluating the architecture of CP lower-limb muscles systematically, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 guidelines. RESULTS: Out of 897 records, 9 publications with 111 CP participants aged 3.8-17.0 years were included (8 focused on intra-rater and inter-rater reliability, 2 focused on validity, and 4 were with high quality). The ultrasound-based measurements of muscle thickness (intra-rater only), muscle length, cross-sectional area, muscle volume, fascicle length, and pennation angle showed high reliability, with the majority of intraclass correlation coefficient (ICC) values being larger than 0.9. Moderate-to-good correlations between ultrasound and magnetic resonance imaging measurements existed in muscle thickness and cross-sectional area (0.62 ≤ ICC ≤ 0.82). INTERPRETATION: Generally, ultrasound has high reliability and validity in evaluating the CP muscle architecture, but this is mainly supported by moderate and limited levels of evidence. More high-quality future studies are needed.


Assuntos
Paralisia Cerebral , Humanos , Paralisia Cerebral/diagnóstico por imagem , Reprodutibilidade dos Testes , Músculo Esquelético/diagnóstico por imagem , Extremidade Inferior/diagnóstico por imagem , Ultrassonografia/métodos
10.
Zhonghua Nan Ke Xue ; 29(5): 409-413, 2023 May.
Artigo em Zh | MEDLINE | ID: mdl-38602756

RESUMO

OBJECTIVE: To investigate the impact of retaining part of the urethral mucosa on postoperative urinary control, erectile function, and ejaculatory function in patients undergoing holmium laser enucleation of the prostate (HoLEP) surgery. METHODS: A retrospective analysis was conducted on 176 benign prostatic hyperplasia (BPH) patients who underwent surgical treatment at our hospital from January 2019 to January 2022, including 80 cases of modified HoLEP surgery and 96 cases of standard HoLEP surgery. Preoperative and postoperative clinical data were collected and analyzed. RESULTS: At 3 months postoperatively, both groups showed significant improvement in maximum flow rate (Qmax), International Prostate Symptom Score (IPSS) , residual urine volume (RUV) , and quality of life (QOL) compared to pre-treatment values, with statistically significant differences (P<0.05) . There was a significant difference in QOL scores between the experimental and control groups (P<0.05) . At 3 months postoperatively, the incidence of urinary incontinence was significantly lower in the experimental group compared to the control group (P<0.05) . At 6 months postoperatively, both groups showed a significant increase in International Index of Erectile Function-5 (IIEF-5) scores compared to preoperative values (P<0.05) , with no significant difference between the two groups. The incidence of retrograde ejaculation in the experimental group was significantly lower than that in the control group (P<0.05) . CONCLUSIONS: Retaining part of the urethral mucosa in HoLEP surgery can effectively treat BPH, providing significant advantages in terms of urinary control and playing a positive role in overall postoperative sexual function recovery.


Assuntos
Disfunção Erétil , Lasers de Estado Sólido , Hiperplasia Prostática , Masculino , Idoso , Humanos , Hiperplasia Prostática/cirurgia , Qualidade de Vida , Lasers de Estado Sólido/uso terapêutico , Disfunção Erétil/etiologia , Próstata , Estudos Retrospectivos , Hólmio
11.
J Neuroinflammation ; 19(1): 236, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36171620

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the most common neurodegenerative disease and its pathogenesis is still unclear. There is dysbiosis of gut microbiota in AD patients. More importantly, dysbiosis of the gut microbiota has been observed not only in AD patients, but also in patients with mild cognitive impairment (MCI). However, the mechanism of gut microbiota dysbiosis in AD is poorly understood. Cholinergic anti-inflammatory pathway is an important pathway for the central nervous system (CNS) regulation of peripheral immune homeostasis, especially in the gut. Therefore, we speculated that dysfunction of cholinergic anti-inflammatory pathway is a potential pathway for dysbiosis of the gut microbiota in AD. METHODS: In this study, we constructed AD model mice by injecting Aß1-42 into the lateral ventricle, and detected the cognitive level of mice by the Morris water maze test. In addition, 16S rDNA high-throughput analysis was used to detect the gut microbiota abundance of each group at baseline, 2 weeks and 4 weeks after surgery. Furthermore, immunofluorescence and western blot were used to detect alteration of intestinal structure of mice, cholinergic anti-inflammatory pathway, and APP process of brain and colon in each group. RESULTS: Aß1-42 i.c.v induced cognitive impairment and neuron damage in the brain of  mice. At the same time, Aß1-42 i.c.v induced alteration of gut microbiota at 4 weeks after surgery, while there was no difference at the baseline and 2 weeks after surgery. In addition, changes in colon structure and increased levels of pro-inflammatory factors were detected in Aß1-42 treatment group, accompanied by inhibition of cholinergic anti-inflammatory pathways. Amyloidogenic pathways in both the brain and colon were accelerated in Aß1-42 treatment group. CONCLUSIONS: The present findings suggested that Aß in the CNS can induce gut microbiota dysbiosis, alter intestinal structure and accelerate the amyloidogenic pathways, which were related to inhibiting cholinergic anti-inflammatory pathways.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Doenças Neurodegenerativas , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/toxicidade , Animais , DNA Ribossômico , Disbiose/induzido quimicamente , Microbioma Gastrointestinal/fisiologia , Ventrículos Laterais/patologia , Camundongos , Neuroimunomodulação
12.
Biotechnol Bioeng ; 119(2): 388-398, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34837379

RESUMO

Xylitol is a salutary sugar substitute that has been widely used in the food, pharmaceutical, and chemical industries. Co-fermentation of xylose and glucose by metabolically engineered cell factories is a promising alternative to chemical hydrogenation of xylose for commercial production of xylitol. Here, we engineered a mutant of SecY protein-translocation channel (SecY [ΔP]) in xylitol-producing Escherichia coli JM109 (DE3) as a passageway for xylose uptake. It was found that SecY (ΔP) channel could rapidly transport xylose without being interfered by XylB-catalyzed synthesis of xylitol-phosphate, which is impossible for native XylFGH and XylE transporters. More importantly, with the coaction of SecY (ΔP) channel and carbon catabolite repression (CCR), the flux of xylose to the pentose phosphate (PP) pathway and the xylitol synthesis pathway in E. coli could be automatically controlled in response to glucose, thereby ensuring that the mutant cells were able to fully utilize sugars with high xylitol yields. The E. coli cell factory developed in this study has been proven to be applicable to a broad range of xylose-glucose mixtures, which is conducive to simplifying the mixed-sugar fermentation process for efficient and economical production of xylitol.


Assuntos
Ciclo do Carbono/genética , Escherichia coli , Engenharia Metabólica/métodos , Xilitol/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Fermentação , Glucose/metabolismo , Canais de Translocação SEC/genética , Xilose/metabolismo
13.
Nucleic Acids Res ; 48(6): 3156-3164, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32009150

RESUMO

The hexametric T7 helicase (gp4) adopts a spiral lock-washer form and encircles a coil-like DNA (tracking) strand with two nucleotides bound to each subunit. However, the chemo-mechanical coupling mechanism in unwinding has yet to be elucidated. Here, we utilized nanotensioner-enhanced Förster resonance energy transfer with one nucleotide precision to investigate gp4-induced unwinding of DNA that contains an abasic lesion. We observed that the DNA unwinding activity of gp4 is hindered but not completely blocked by abasic lesions. Gp4 moves back and forth repeatedly when it encounters an abasic lesion, whereas it steps back only occasionally when it unwinds normal DNA. We further observed that gp4 translocates on the tracking strand in step sizes of one to four nucleotides. We propose that a hypothetical intermediate conformation of the gp4-DNA complex during DNA unwinding can help explain how gp4 molecules pass lesions, providing insights into the unwinding dynamics of gp4.


Assuntos
Bacteriófago T7/genética , DNA Helicases/genética , DNA Primase/genética , DNA/genética , Bacteriófago T7/química , DNA/química , DNA Primase/química , Transferência Ressonante de Energia de Fluorescência , Cinética , Conformação Molecular , Nucleotídeos/química , Nucleotídeos/genética
14.
Sensors (Basel) ; 22(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35161761

RESUMO

Gas sensing performance characterization systems are essential for the research and development of gas sensing materials and devices. Although existing systems are almost completely automatically operated, the accuracies of gas concentration control and of pressure control and the ability to simultaneously detect different sensor signals still require improvement. In this study, a high-precision gas sensing material characterization system is developed based on vacuum technology, with the objective of enabling the precise and simultaneous measurement of electrical responses. Because of the implementation of vacuum technology, the gas concentration control accuracy is improved more than 1600 times, whereas the pressure of the test ambient condition can be precisely adjusted between vacuum and 1.2 bar. The vacuum-assisted gas-exchanging mechanism also enables the sensor response time to be determined more accurately. The system is capable of performing sensitivity, selectivity, and stability tests and can control the ambient relative humidity in a precise manner. More importantly, the levels of performance of three different optical signal measurement set-ups were investigated and compared in terms of detection range, linearity, noise, and response time, based on which of their scopes of application were proposed. Finally, single-period and cyclical tests were performed to examine the ability of the system to detect optical and electrical responses simultaneously, both at a single wavelength and in a spectral region.

15.
Undersea Hyperb Med ; 49(4): 507-518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36446296

RESUMO

Background: Early recompression therapy is suggested for a better clinical outcome of decompression sickness (DCS) patients. This study analyzed the efficacy of our 24-hour on-call system for early recompression therapy. Methods: We conducted a single-center retrospective cohort study. They were classified into DCS Type I versus Type II, duty time versus non-duty time groups based on the time of emergency department (ED) admission, and hospitalization versus discharge groups according to clinical outcomes. Baseline characteristics, diving variables, and in-hospital course were analyzed. Results: This study investigated 341 acute DCS patients. A total of 81 and 260 patients had Type I and Type II DCS, respectively. While 198 patients accessed the center during duty time, 143 presented during non-duty time. Fifty patients were admitted, and 291 patients were discharged. Total median time from symptom onset to HBO2 therapy was 259 minutes: 240 minutes for the duty group and 292 minutes for the non-duty group (p=0.16); 251 minutes for the discharged group and 291 minutes for the hospitalized group (p<0.001). The median time from ED admission to HBO2 therapy was 65 minutes: 60 minutes for the duty group and 69 minutes for the non-duty group (p=0.23); 63.4 minutes for the discharged group and 92 minutes for the hospitalized group (p=0.05). Conclusion: The 24-hour on-call system was able to provide acute DCS patients with early recompression therapy even during non-duty time. However, in terms of the outcome of treatment of patients, quicker arrival at the hospital and swifter recompression therapy are needed.


Assuntos
Doença da Descompressão , Mergulho , Humanos , Doença da Descompressão/terapia , Estudos Retrospectivos , Prevenção Secundária , Hospitalização
16.
Neurochem Res ; 46(5): 1068-1080, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33683629

RESUMO

Alzheimer's disease (AD) process is characterized classically by two hallmark pathologies: ß-amyloid (Aß) plaque deposition and neurofibrillary tangles of hyperphosphorylated tau. Aß peptides play an important role in AD, but despite much effort the molecular mechanisms of how Aß contributes to AD remain unclear. The present study evaluated the effects of the active components of Epimedium, Astragalus and Radix Puerariae induced HAMP on key enzymes in the hydrolysis of APP in HT22 cells. The active components of Epimedium, Astragalus and Radix Puerariae could effectively up-regulate the expression of HAMP, alleviate the iron overload in the brain tissues of mice, significantly improve the learning and memory ability of AD, down-regulate the expression of Aß and reduce the deposition of SP in an APPswe/PS1ΔE9 transgenic mouse model of AD. HAMP and Aß25-35 induced HT22 cells are used as AD cell models in this study to investigate the effect of the compound consisting of the effective components of Epimedium, Astragalus and Pueraria on the key enzymes in the hydrolysis of APP. After the administration of traditional Chinese medicine (TCM), the expression levels of ADAM10 and ADAM17 were increased while the expression level of BACE1 decreased. This indicates that TCM can promote the expression level of ADAM10 and ADAM17, inhibit the expression level of BACE1, thus further inhibiting the production of amyloid protein and reducing the production of Aß and SP. Compared with RNAi group, the expression level of ADAM10 and ADAM17 in Aß + RNAi group was decreased while the expression level of BACE1 increased. Compared with the Aß + RNAi group the expression level of ADAM10 and ADAM17 in the Aß + RNAi + TCM group was increased while the expression level of BACE1 was decreased. The present study indicated the effects of the active components of Epimedium, Astragalus and Radix Puerariae may alleviate AD by up-regulating the expression of HAMP, thus reducing brain iron overload, promoting the expression of ADAM10 and ADAM17, inhibiting the expression of BACE1, and reducing the deposition of Aß.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Hepcidinas/metabolismo , Fármacos Neuroprotetores/farmacologia , Proteólise/efeitos dos fármacos , Proteína ADAM10/metabolismo , Proteína ADAM17/metabolismo , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Camundongos , Fragmentos de Peptídeos/farmacologia , Regulação para Cima/efeitos dos fármacos
18.
Int J Clin Pract ; 75(12): e14738, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34399017

RESUMO

PURPOSE: Atrial fibrillation (AF) is one of the most common persistent arrhythmia, and its complications include cerebral embolism, arterial embolism and heart failure. Some studies have found that elevated Homocysteine (HCY) levels is a new risk factor for AF. Currently, there is no meta-analysis to explore whether the HCY levels is related to AF. Therefore, a meta-analysis was conducted to evaluate the relationship between the HCY levels and AF, in order to draw the attention of clinicians to the HCY levels. METHODS: A meta-analysis was performed in the study to evaluated the association between the HCY levels and AF. In order to identify eligible original articles, The EMBASE, PubMed, and web of science were systematically searched until November 2020. All data were analyzed with Review Manager 5.3. The meta-analysis results were evaluated depending on standardized mean differences (SMD) with 95% confidence intervals (CI). Moreover, the subgroup analysis and sensitivity analysis were also analyzed. RESULTS: The HCY levels was significantly associated with AF (WMD = 0.81, 95% CI: 0.58 to 1.03; P < .00001). In the analysis, there was a medium degree of heterogeneity (I2 = 73%). Subgroup analysis showed that female < 60, BMI≥25, BMI <25, age ≥60 and publication year ≥2010 were identified as possible sources of heterogeneity. Sensitivity analysis showed that the main results remained unchanged after omitting any single study or converting the random effects model (REM) to fixed effects model (FEM). CONCLUSIONS: The meta-analysis showed that there is a significant correlation between the HCY levels and AF, and the role of HCY in AF patients should not be ignored in clinical.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Feminino , Homocisteína , Humanos , Fatores de Risco
19.
Eur Spine J ; 30(3): 668-675, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32767126

RESUMO

PURPOSE: The coronal Cobb angle is commonly used for assessing the adolescent idiopathic scoliosis (AIS); however, it may underestimate the severity of AIS while the plane of maximum curvature (PMC) could be a promising descriptor for three-dimensional assessment of AIS. This study aimed to develop a computational method (CM) for estimating the PMC based on the coronal and sagittal images of the spine, and to verify the results with computed tomography (CT). METHODS: Twenty-eight thoracic and 24 lumbar curves from 30 subjects with AIS were analysed. For the CM, PMC was estimated via identifying the two corner points at the superior endplate of upper-end vertebra and the inferior endplate of lower-end vertebra in the coronal and sagittal CT images separately (eight corner points in total). For the CT, PMC was determined through rotating the spine images axially until the maximum Cobb angle was found. Intraclass correlation coefficient (ICC), Bland-Altman method and linear regression analysis were used for the statistical analyses. RESULTS: The high ICC values (intra- > 0.91; inter- > 0.84) suggested very good intra- and inter-rater reliability of the CM in PMC estimation. The high ICC values (> 0.91) and assessment of Bland-Altman method demonstrated a good agreement between the PMC acquired using the CM and CT. The generated linear regression equations (R2 > 0.69) could allow to estimate the PMC (originally measured through the CT) via the CM. CONCLUSION: The developed computational method could estimate reliable and valid PMC for the patients with AIS, and become feasible for three-dimensional assessment of AIS. LEVEL OF EVIDENCE: III.


Assuntos
Cifose , Escoliose , Adolescente , Humanos , Reprodutibilidade dos Testes , Escoliose/diagnóstico por imagem , Coluna Vertebral , Tomografia Computadorizada por Raios X
20.
Sensors (Basel) ; 21(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34502862

RESUMO

In this paper, a simple printed cross-dipole (PCD) antenna to achieve a right-hand circular polarization (RHCP) at the L/S-band for direction finding (DF) systems is presented. The radiating part of the antenna consists of two printed dipoles that interlock with each other and are mounted orthogonally on a dual-layer printed reflector. To connect the feedlines of the dipole elements to the antenna's feed network, which is located on the backside of the reflector, a through-hole signal via (THSV) is employed as the signal interconnection instead of the mainstream approach of using coaxial bead conductor. This feeding technique provides a degree of freedom to control the impedance of the signal path between the feedlines and the feed network in the numerical simulation for improved matching conditions. The proposed THSV extending through the dual-layer printed reflector is more reliable, durable, and mechanically robust to stabilize the matching conditions of the fabricated antenna in contrast to the coaxial-based approach that is more susceptible to impedance mismatch due to solder fatigue. Thus, the proposed PCD antenna offers advantages of broadband, flexible impedance matching, and fabrication ease. The antenna exhibits an impedance bandwidth (IBW) of 59% (1.59-2.93 GHz), a 3-dB axial ratio bandwidth (ARBW) of 57% (1.5-2.7 GHz), and a peak of 7.5 dB within the operating frequency band.

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