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1.
J Phys Chem A ; 128(28): 5459-5472, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38973649

RESUMO

In this study, we employ density functional theory along with the artificial bee colony algorithm for cluster global optimization to explore the low-lying structures of TeBnq (n = 3-16, q = 0, -1). The primary focus is on reporting the structural properties of these clusters. The results reveal a consistent doping pattern of the tellurium atom onto the in-plane edges of planar or quasi-planar boron clusters in the most energetically stable isomers. Additionally, we simulate the photoelectron spectra of the cluster anions. Through relative stability analysis, we identify three clusters with magic numbers -TeB7-, TeB10, and TeB12. The aromaticity of these clusters is elucidated using adaptive natural density partitioning (AdNDP) and magnetic properties analysis. Notably, TeB7- exhibits a perfect σ-π doubly aromatic structure, while TeB12 demonstrates strong island aromaticity. These findings significantly contribute to our understanding of the structural and electronic properties of these clusters.

2.
Int J Surg ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905504

RESUMO

BACKGROUD: Endoscopic thyroidectomy (ET) and robotic thyroidectomy (RT) yield similar perioperative outcomes. This study investigated how the learning curve (LC) affects perioperative outcomes between ET and RT, identifying factors that influence the LC. MATERIALS AND METHODS: Two researchers individually searched PubMed, EMBASE, Web of Science, and Cochrane Library for relevant studies published until February 2024. The Newcastle-Ottawa Scale assessed study quality. Random effects model was used to compute the odds ratio and weighted mean difference (WMD). Poisson regression comparison of the number of surgeries (NLC) was required for ET and RT to reach the stable stage of the LC. Heterogeneity was measured using Cochran's Q. Publication bias was tested using funnel plots, and sensitivity analysis assessed findings robustness. Subgroup analysis was done by operation type and patient characteristics. RESULTS: This meta-analysis involved 33 studies. The drainage volume of ET was higher than that of RT (WMD=-17.56 [30.22, -4.49]). After reaching the NLC, the operation time of ET and RT was shortened (ET: WMD=28.15[18.04, 38.26]; RT: WMD=38.53[29.20, 47.86]). Other perioperative outcomes also improved to varying degrees. Notably, RT showed more refined central lymph node resection(5.67 vs. 4.71), less intraoperative bleeding (16.56 mL vs. 42.30 mL), and incidence of transient recurrent laryngeal nerve injury(24.59 vs. 26.77). The NLC of RT was smaller than that of ET(Incidence-rate ratios [IRR]=0.64[0.57, 0.72]). CUSUM analysis (ET: IRR=0.84[0.72, 0.99]; RT: IRR=0.55[0.44, 0.69]) or a smaller number of respondents (ET: IRR=0.26[0.15, 0.46]; RT: IRR=0.51[0.41, 0.63]) was associated with smaller NLC. In RT, transoral approach (IRR=2.73[1.96, 4.50]; IRR=2.48[1.61, 3.84]) and retroauricular approach (RAA) (IRR=2.13[1.26, 3.60]; IRR=1.78[1.04, 3.05]) had smaller NLC compared to bilateral axillo-breast and transaxillary approach (TAA). In ET, the NLC of RAA was smaller than that of TAA (IRR=1.61[1.04, 2.51]), breast approach(IRR=1.67[1.06, 2.64]), and subclavian approach(IRR=1.80[1.03, 3.14]). CONCLUSIONS: Rich surgical experience can improve surgical results of ET and RT. After reaching the NLC, the perioperative outcomes of RT are better than those of ET. Study subjects, surgical approaches, and analysis methods can affect NLC.

3.
Hepatology ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630497

RESUMO

BACKGROUND AND AIMS: The utility of serial liver stiffness measurements (LSM) to predict decompensation in patients with compensated advanced chronic liver disease (cACLD) remains unclear. We aimed to validate whether comparing serial LSM is superior to using the current LSM to predict liver-related events (LRE) in patients with cACLD. APPROACH AND RESULTS: In this retrospective analysis of an international registry, patients with cACLD and serial LSM were followed up until index LRE. We compared the performance of both the dynamic LSM changes and the current LSM in predicting LRE using Cox regression analysis, considering time zero of follow-up as the date of latest liver stiffness measurement. In all, 480 patients with cACLD with serial LSM were included from 5 countries. The commonest etiology of cACLD was viral (53%) and MASLD (34%). Over a median follow-up of 68 (IQR: 45 -92) months, 32% experienced a LSM decrease to levels below 10kPa (resolved cACLD) and 5.8% experienced LRE. Resolved cACLD were more likely to be nondiabetic and had better liver function. While a higher value of the current LSM was associated with higher LREs, LSM changes over time (LSM slope) were not associated with LRE. In multivariable Cox regression, neither the prior LSM nor the LSM slope added predictive value to latest liver stiffness measurement. CONCLUSIONS: Once the current LSM is known, previous LSM values do not add to the prediction of LREs in patients with cACLD.

4.
Anal Chem ; 96(10): 4275-4281, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38409670

RESUMO

Surface-enhanced Raman scattering (SERS) can overcome the existing technological limitations, such as complex processes and harsh conditions in gaseous small-molecule detection, and advance the development of real-time gas sensing at room temperature. In this study, a SERS-based hydrogen bonding induction strategy for capturing and sensing gaseous acetic acid is proposed for the detection demands of gaseous acetic acid. This addresses the challenges of low adsorption of gaseous small molecules on SERS substrates and small Raman scattering cross sections and enables the first SERS-based detection of gaseous acetic acid by a portable Raman spectrometer. To provide abundant hydrogen bond donors and acceptors, 4-mercaptobenzoic acid (4-MBA) was used as a ligand molecule modified on the SERS substrate. Furthermore, a sensing chip with a low relative standard deviation (RSD) of 4.15% was constructed, ensuring highly sensitive and reliable detection. The hydrogen bond-induced acetic acid trapping was confirmed by experimental spectroscopy and density functional theory (DFT). In addition, to achieve superior accuracy compared to conventional methods, an innovative analytical method based on direct response hydrogen bond formation (IO-H/Iref) was proposed, enabling the detection of gaseous acetic acid at concentrations as low as 60 ppb. The strategy demonstrated a superior anti-interference capability in simulated breath and wine detection systems. Moreover, the high reusability of the chip highlights the significant potential for real-time sensing of gaseous acetic acid.

5.
J Phys Chem Lett ; 15(5): 1507-1514, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38299556

RESUMO

Electron delocalization has an important impact on the physical properties of condensed materials. However, the L-electron delocalization in inorganic, especially nitrogen, compounds needs exploitation to improve the energy efficiency, safety, and environmental sustainability of high-energy-density materials (HEDMs). This Letter presents an intriguing N8 molecule, ingeniously utilizing nitrogen's L-electron delocalization. The molecule, exhibiting a unique lollipop-shaped conformation, can fold at various angles with very low energy barriers, self-assembling into environmentally stable, all-nitrogen crystals. These crystals demonstrate unparalleled stability, high energy density, low mechanical sensitivity, and optimal electronic thermal conductivity, outperforming existing HEDMs. The remarkable properties of these designed materials are attributed to two distinct delocalized systems within nitrogen's L-shell: π- and lone pair σ-electrons, which not only stabilize the molecular structure but also facilitate interconnected 3D networks of intermolecular nonbonding interactions. This work might pave the way to the experimental synthesis of environmentally stable all-nitrogen solids.

6.
J Comput Chem ; 45(14): 1087-1097, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38243618

RESUMO

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe 6 - (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials.

7.
Obes Rev ; 25(4): e13691, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38186200

RESUMO

In this review, we delve into the intricate relationship between white adipose tissue (WAT) remodeling and metabolic aspects in obesity, with a specific focus on individuals with metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO). WAT is a highly heterogeneous, plastic, and dynamically secreting endocrine and immune organ. WAT remodeling plays a crucial role in metabolic health, involving expansion mode, microenvironment, phenotype, and distribution. In individuals with MHO, WAT remodeling is beneficial, reducing ectopic fat deposition and insulin resistance (IR) through mechanisms like increased adipocyte hyperplasia, anti-inflammatory microenvironment, appropriate extracellular matrix (ECM) remodeling, appropriate vascularization, enhanced WAT browning, and subcutaneous adipose tissue (SWAT) deposition. Conversely, for those with MUO, WAT remodeling leads to ectopic fat deposition and IR, causing metabolic dysregulation. This process involves adipocyte hypertrophy, disrupted vascularization, heightened pro-inflammatory microenvironment, enhanced brown adipose tissue (BAT) whitening, and accumulation of visceral adipose tissue (VWAT) deposition. The review underscores the pivotal importance of intervening in WAT remodeling to hinder the transition from MHO to MUO. This insight is valuable for tailoring personalized and effective management strategies for patients with obesity in clinical practice.


Assuntos
Resistência à Insulina , Obesidade Metabolicamente Benigna , Humanos , Obesidade/metabolismo , Adiposidade , Tecido Adiposo Branco/metabolismo , Tecido Adiposo/metabolismo
8.
Viruses ; 15(7)2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37515176

RESUMO

About 5% of chronic hepatitis C (CHC) patients experienced treatment failure with direct-acting antiviral (DAA) treatment. The global data on the practice and treatment outcomes of Sofosbuvir/Velpatasvir/Voxilaprevir (SOF/VEL/VOX) in DAA-experienced CHC patients remains sparse. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of SOF/VEL/VOX as a salvage treatment in DAA-experienced CHC patients. We searched five electronic databases from inception to 31 January 2023. The study outcomes were SVR12 and treatment-related adverse effects, with subgroup analysis performed based on genotype, cirrhosis, HCC, prior SOF/VEL exposure, and region. We identified and analyzed data from 24 studies (2877 DAA-experienced CHC patients); 17.2% had prior SOF/VEL exposure, 25% received ribavirin with SOF/VEL/VOX, and 42% had pre-treatment resistance-associated substitution (RAS) testing performed. Eastern Mediterranean had a higher pooled SVR12 than the America and Europe regions (p < 0.05). Predictors of SOF/VEL/VOX failure were genotype 3, active HCC, baseline cirrhosis, and prior SOF/VEL. Baseline RAS mutation and ribavirin supplementation were not associated with higher SVR12. Treatment discontinuation because of drug-related adverse events was uncommon (10 studies, 0.2%). In summary, SOF/VEL/VOX is efficacious and safe for retreatment in DAA-experienced CHC patients, even with RAS mutation. Our findings support SOF/VEL/VOX as a first-line rescue treatment for DAA-experienced CHC patients.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Humanos , Antivirais/efeitos adversos , Sofosbuvir/efeitos adversos , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Ribavirina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Resposta Viral Sustentada , Neoplasias Hepáticas/tratamento farmacológico , Resultado do Tratamento , Hepatite C/tratamento farmacológico , Genótipo , Quimioterapia Combinada
9.
Int J Surg ; 109(7): 2070-2081, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37318897

RESUMO

BACKGROUND: Thyroid disease is a common endocrine disorder, and thyroid surgeries and postoperative complications have increased recently. This study aimed to explore the effectiveness of intraoperative nerve monitoring (IONM) in endoscopic thyroid surgery using subgroup analysis and determine confounding factors. MATERIALS AND METHODS: Two researchers individually searched for relevant studies published till November 2022 in the PubMed, Embase, Web of Science and Cochrane Library databases. Eventually, eight studies met the inclusion criteria. Heterogeneity was assessed using the Cochran's Q test, and a funnel plot was implemented to evaluate publication bias. The odds ratio or risk difference were calculated using fixed-effects models. The weighted mean difference of continuous variables was calculated. Subgroup analysis was performed according to the disease type. RESULTS: Eight eligible papers included 915 patients and 1242 exposed nerves. The frequencies of transient, permanent and total recurrent laryngeal nerve (RLN) palsy were 2.64, 0.19 and 2.83%, respectively, in the IONM group and 6.15, 0.75 and 6.90%, respectively, in the conventional exposure group. In addition, analysis of the secondary outcome indicators for the average total length of surgery, localisation time of the RLN, recognition rate of the superior laryngeal nerve and length of incision revealed that IONM reduced the localisation time of the RLN and increased the identification rate of the superior laryngeal nerve. Subgroup analysis showed that IONM significantly reduced the incidence of RLN palsy in patients with malignancies. CONCLUSIONS: The use of IONM significantly reduced the incidence of transient RLN palsy during endoscopic thyroid surgery, but it did not significantly reduce the incidence of permanent RLN palsy. However, the reduction in the total RLN palsy was statistically significant. In addition, IONM can effectively reduce the location time of the RLN and increase the recognition rate of the superior laryngeal nerve. Therefore, the application of IONM for malignant tumours is recommended.


Assuntos
Traumatismos do Nervo Laríngeo Recorrente , Paralisia das Pregas Vocais , Humanos , Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos , Nervo Laríngeo Recorrente/fisiologia , Monitorização Intraoperatória , Traumatismos do Nervo Laríngeo Recorrente/etiologia , Traumatismos do Nervo Laríngeo Recorrente/prevenção & controle , Paralisia das Pregas Vocais/etiologia , Paralisia das Pregas Vocais/prevenção & controle
10.
Exp Ther Med ; 25(5): 203, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37090071

RESUMO

The clinical features and risk factors for survival time were analysed in haemodialysis patients complicated with infective endocarditis. A total of 101 infective endocarditis (IE) patients treated at Hangzhou First People's Hospital, from January 1, 2012, to April 1, 2022, were included in the present study. Baseline demographic data and laboratory data were collected for statistical analysis of risk factors and survival time in the IE with haemodialysis group (HD-IE group, n=15) and the IE without haemodialysis group (NHD-IE group, n=86). Haemoglobin, red blood cells, C-reactive protein, procalcitonin, serum albumin, diabetes, invasive procedures, positive blood bacteria culture, heart valve calcification ratio, and left ventricular ejection fraction level were risk factors for infective endocarditis complicated with haemodialysis (P<0.05). Compared with the NHD-IE group, the HD-IE group had an obviously increased risk of mortality (χ2=6.323, P=0.012). The univariate Cox regression analysis showed that age, haemoglobin, red blood cells, serum albumin, left ventricular ejection score, longest vegetation diameter, combined hypotension and diabetes were risk factors for death; furthermore, multivariate Cox regression showed that age (HR=1.187, P=0.015), combined hypotension (HR=0.921, P=0.025) and the longest vegetation diameter (HR=9.191, P=0.004) were independent risk factors affecting the survival of patients. Collectively, the present study revealed that the mortality rate of HD-IE patients was higher than that of NHD-IE patients. Older age, hypotension, and the longest vegetation diameter were independent risk factors affecting the survival of patients. For HD-IE patients, active and effective antibiotic treatment or surgical treatment should be strongly recommended.

11.
Mol Ecol ; 32(3): 613-627, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36355347

RESUMO

Invasive species can successfully and rapidly colonize new niches and expand ranges via founder effects and enhanced tolerance towards environmental stresses. However, the underpinning molecular mechanisms (i.e., gene expression changes) facilitating rapid adaptation to harsh environments are still poorly understood. The red seaweed Gracilaria vermiculophylla, which is native to the northwest Pacific but invaded North American and European coastal habitats over the last 100 years, provides an excellent model to examine whether enhanced tolerance at the level of gene expression contributed to its invasion success. We collected G. vermiculophylla from its native range in Japan and from two non-native regions along the Delmarva Peninsula (Eastern United States) and in Germany. Thalli were reared in a common garden for 4 months at which time we performed comparative transcriptome (mRNA) and microRNA (miRNA) sequencing. MRNA-expression profiling identified 59 genes that were differently expressed between native and non-native thalli. Of these genes, most were involved in metabolic pathways, including photosynthesis, abiotic stress, and biosynthesis of products and hormones in all four non-native sites. MiRNA-based target-gene correlation analysis in native/non-native pairs revealed that some target genes are positively or negatively regulated via epigenetic mechanisms. Importantly, these genes are mostly associated with metabolism and defence capability (e.g., metal transporter Nramp5, senescence-associated protein, cell wall-associated hydrolase, ycf68 protein and cytochrome P450-like TBP). Thus, our gene expression results indicate that resource reallocation to metabolic processes is most likely a predominant mechanism contributing to the range-wide persistence and adaptation of G. vermiculophylla in the invaded range. This study, therefore, provides molecular insight into the speed and nature of invasion-mediated rapid adaption.


Assuntos
Gracilaria , Rodófitas , Alga Marinha , Alga Marinha/genética , Gracilaria/genética , Ecossistema , Expressão Gênica
12.
Asian J Androl ; 24(6): 591-593, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35435337

RESUMO

This study aimed to investigate the curative effect of spiral embedded flap urethroplasty for the treatment of meatal stenosis after penile carcinoma surgery. From January 2015 to January 2021, we used our technique to treat strictures of the external urethral orifice in seven patients, including four cases of meatal stenosis after partial penile resection and three cases of meatal stenosis after perineal stoma. All patients had previously undergone repeat urethral dilatation. The patients underwent spiral embedded flap urethroplasty to enlarge the outer urethral opening. The patients' mean age at the time of surgery was 60 (range: 42-71) years, the mean operative time was 43 min, and the median follow-up period was 18 months. The patients voided well post-operatively, and urinary peak flow rates ranged from 18.3 ml s-1 to 30.4 ml s-1. All patients were successful with absence of urethral meatus stricture. The present study showed that using spiral embedded flap urethroplasty to treat meatal stenosis after penile carcinoma surgery is an effective surgical technique with good long-term outcomes.


Assuntos
Carcinoma , Neoplasias Penianas , Estreitamento Uretral , Masculino , Humanos , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Neoplasias Penianas/cirurgia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Resultado do Tratamento , Estreitamento Uretral/etiologia , Estreitamento Uretral/cirurgia , Uretra/cirurgia , Amputação Cirúrgica , Carcinoma/cirurgia , Estudos Retrospectivos
13.
ACS Appl Mater Interfaces ; 13(48): 56838-56849, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34816709

RESUMO

Antimicrobial resistance in Gram-negative bacteria has become one of the leading causes of morbidity and mortality and a serious worldwide public health concern due to the fact that Gram-negative bacteria have an additional outer membrane protecting them from an unwanted compound invading. It is still very difficult for antimicrobials to reach intracellular targets and very challenging to treat Gram-negative bacteria with the current strategies. Here, we found that (o-(bromomethyl)phenyl)boronic acid was incorporated into poly((2-N,N-diethyl)aminoethyl acrylate) (PDEA), forming a copolymer (poly(o-Bn-DEA)) having both phenylboronic acid (B) and ((2-N,N-diethyl)amino) (DEA) units. Poly(o-Bn-DEA) exhibits very strong intramolecular B-N coordination, which could highly promote the covalent binding of phenylboronic acid with lipopolysaccharide (LPS) on the outer membrane of E. coli and lodge poly(o-Bn-DEA) on the LPS layer on the surface of E. coli. Meanwhile, the strong electrostatic interaction between poly(o-Bn-DEA) and the negatively charged lipid preferred tugging the poly(o-Bn-DEA) into the lipid bilayer of E. coli. The combating interactions between covalent binding and electrostatic interaction form a tug-of-war action, which could trigger the lysis of the outer membrane, thereby killing Gram-negative E. coli effectively without detectable resistance.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Materiais Biomiméticos/farmacologia , Escherichia coli/efeitos dos fármacos , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Sítios de Ligação/efeitos dos fármacos , Materiais Biomiméticos/química , Teste de Materiais , Testes de Sensibilidade Microbiana , Eletricidade Estática
14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-906378

RESUMO

Objective:To explore the correlation of the botanical characteristics, biological characteristics, habitat, and medicinal property and efficacy of parasitic Chinese medicines, underpin quality evaluation based on property differentiation, and provide references for the development and utilization of parasitic medicinal plant resources. Method:The origin, property and meridian tropism, parasitic type, and the efficacy of the common of parasitic Chinese medicines were summarized. The frequencies of parasitic Chinese medicines in Qingfei Paidu decoction,<italic> Medicine Food Homology</italic>, <italic>Catalogue of Ancient Classical Formulas (the first batch)</italic>, and the 2020 edition of <italic>Chinese Pharmacopoeia</italic> were statistically analyzed. Excel 2013 and SPSS Statistics 23.0 were employed for statistical research. Result:The ranking results of parasitic Chinese medicines are listed below: root parasitism>stem parasitism>root hemiparasitism>symbiosis=saprophytism according to the parasitic type, plain>warm>cool>cold, no heat involved according to nature, sweet>bitter>pungent>sour=salt, with one sweet-pungent, one sweet-bitter, one sweet-salt, and one bitter-salt Chinese medicine according to flavor, kidney>liver>large intestine>spleen>lung>heart=bladder, no small intestine meridian involved according to meridian tropism. Conclusion:Parasitic Chinese medicines were mostly root-parasitic, plain in nature, sweet in flavor, and entered kidney meridian, with main effects of dispelling wind-dampness, nourishing liver and kidney, clearing heat, and removing toxin. The morphology, habit, and habitat of parasitic Chinese medicine were correlated with the property and efficacy. This study is expected to provide comprehensive references and a theoretical basis for in-depth research, clinical application, and resource development.

15.
Zhongguo Zhong Yao Za Zhi ; 45(21): 5219-5225, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33350238

RESUMO

This study aimed to clarify the microbial diversity, dominant species and the change of community structures in the fermentation of Liushenqu(Massa Medicata Fermentata), and explore the material foundation of its pharmacodynamics effect. On the basis of standardizing the fermentation process, Massa Medicata Fermentata was prepared by screening and optimizing the recipes and the standard formula issued by the Ministry. The community structure and growth process of fungi and bacteria in the samples at five time points(0, 17, 41, 48, 65 h) in the fermentation process of Massa Medicata Fermentata were analyzed by using isolation and culture of eight different media and high-throughput DNA sequencing technology. The results indicated that the samples of the two recipes pre-sented high microbial diversity at the initial fermentation stage, with Aspergillus spp. as the dominant species. As the fermentation process goes forward, Saccharomycopsis fibuligera and Rhizopus oryzae soon became dominant species from 17 h after fermentation commencement point to the fermentation end, while the other species were inhibited at a lower level from 17 h. The species diversity of bacteria in the initial fermentation samples was also high, and Enterobacter was the dominant species. Enterobacter cloacae, Pediococcus pentosaceus and Cronobacter sakazakii became dominant bacterial species 17 h after fermentation commencement, while the species diversity was decreased. Our results will be a scientific basis for promoting the fermentation process of Massa Medicata Fermentata by using pure microbial cultures.


Assuntos
Medicamentos de Ervas Chinesas , Microbiota , Fermentação , Fungos/genética , Saccharomycopsis
16.
Arch Microbiol ; 202(6): 1507-1515, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32222778

RESUMO

Pyocyanin produced by Pseudomonas aeruginosa is a key virulence factor that often causes heavy damages to airway and lung in patients. Conversion of phenazine-1-carboxylic acid to pyocyanin involves an extrametabolic pathway that contains two enzymes encoded, respectively, by phzM and phzS. In this study, with construction of the rpoS-deficient mutant, we first found that although phenazine production increased, pyocyanin produced in the mutant YTΔrpoS was fourfold much higher than that in the wild-type strain YT. To investigate this issue, we constructed phzM-lacZ fusion on a vector and on the chromosome. By quantifying ß-galactosidase activities, we confirmed that expression of the phzM was up-regulated when the rpoS gene was inactivated. However, no changes occurred in the expression of phzS and phzH when the rpoS was knocked out. Taken together, overproduction of the SAM-dependent methyltransferase (PhzM) might contribute to the increased pyocyanin in the absence of RpoS in P. aeruginosa.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Metiltransferases/biossíntese , Oxigenases de Função Mista/biossíntese , Pseudomonas aeruginosa/metabolismo , Piocianina/biossíntese , Fator sigma/genética , Humanos , Metiltransferases/genética , Oxigenases de Função Mista/genética , Fenazinas/metabolismo , Pseudomonas aeruginosa/genética , Fatores de Virulência/metabolismo
17.
J Biomater Sci Polym Ed ; 31(3): 376-393, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31724490

RESUMO

Biological modifications of the silk fibroin (silk) material have broad applications in textiles, biomedical materials and other industrial materials. It is economical to incorporate nanoparticles to the biosynthesis of silk fibroin by adding them to silkworm larval diets. This strategy may result in the rapid stable production of modified silk. Glucose-coated silver nanoparticles (AgNPs) were used to improve the AgNPs' biocompatibility, and the AgNPs were efficiently incorporated into silk by feeding. Larvae fed with AgNPs produced silk with significantly improved antibacterial properties and altered silk secondary structures. Both positive and negative effects on the growth and synthesis of silk proteins were observed after different AgNPs doses. Larvae feeding with low concentration of 0.02% and medium 0.20% AgNPs have greater transfer efficiencies of AgNPs to silk compared with feeding high concentration of 2.00% AgNPs. In addition, the elongation and tensile strength of the produced silk fibers were also significantly increased, with greater mammalian cell compatibility. The appropriate AgNPs concentration in the diet of silkworms can promote the synthesis of silk proteins, enhance their mechanical properties, improve their antibacterial property and inhibit the presence of Gram-negative bacteria.


Assuntos
Bombyx/efeitos dos fármacos , Dieta , Fibroínas/biossíntese , Glucose/química , Nanopartículas Metálicas/química , Prata/química , Água/química , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bombyx/metabolismo , Escherichia coli/efeitos dos fármacos , Fibroínas/química , Fibroínas/farmacologia , Larva/efeitos dos fármacos , Larva/metabolismo , Estrutura Secundária de Proteína , Prata/farmacologia , Solubilidade , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-793313

RESUMO

Objective To evaluate clinical factors associated with laboratory-confirmed influenza infection and probe into the effects of different influenza-like illness(ILI) definitions on influenza surveillance in hospitalized children. Methods The influenza surveillance on the hospitalized children with acute respiratory infection was carried out in Soochow university affiliated children’s hospital from October 2017 to May 2018. The definition of influenza-like illness(ILI), which proposed by world health organization (WHO), the European center for disease prevention and control (ECDC) and ministry of public health of China, was analyzed to determine the area under receiver operating characteristic curve (ROC), sensibility, specificity, and the positive and negative predictive values of the ILI definition using the laboratory evidence of influenza virus infection as golden criteria. Logistic regression model was employed to explore the risk factors of the laboratory confirmed influenza infection among the hospitalized children. Results Of the enrolled 1 459 hospitalized children, 204(14.0%) were lab-confirmed influenza cases. The ECDC definition had the highest sensitivity (91.7%, 95% CI: 87.9%-95.5%) but the lowest specificity (44.6%, 95% CI: 41.9%-47.4%). The WHO definition had the lowest specificity (70.6%, 95% CI: 64.3%-76.8%). China’s definition was the most discriminant definition with relatively high sensitivity (91.2%, 95% CI: 87.3%-95.1%) and specificity (51.5%, 95% CI: 48.8%-54.3%), and its positive area under curve value (71.2%, 95% CI: 67.9%-74.5%) was the highest. Multivariate analysis model showed that the detection rate of influenza virus in children with fever (≥38 ℃) was higher than that in children without fever (OR=7.03, 95% CI:3.89-12.70). Conclusions It is suggested to adopt China’s ILI definition to get better output during influenza surveillance among hospitalized children.

19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-878808

RESUMO

This study aimed to clarify the microbial diversity, dominant species and the change of community structures in the fermentation of Liushenqu(Massa Medicata Fermentata), and explore the material foundation of its pharmacodynamics effect. On the basis of standardizing the fermentation process, Massa Medicata Fermentata was prepared by screening and optimizing the recipes and the standard formula issued by the Ministry. The community structure and growth process of fungi and bacteria in the samples at five time points(0, 17, 41, 48, 65 h) in the fermentation process of Massa Medicata Fermentata were analyzed by using isolation and culture of eight different media and high-throughput DNA sequencing technology. The results indicated that the samples of the two recipes pre-sented high microbial diversity at the initial fermentation stage, with Aspergillus spp. as the dominant species. As the fermentation process goes forward, Saccharomycopsis fibuligera and Rhizopus oryzae soon became dominant species from 17 h after fermentation commencement point to the fermentation end, while the other species were inhibited at a lower level from 17 h. The species diversity of bacteria in the initial fermentation samples was also high, and Enterobacter was the dominant species. Enterobacter cloacae, Pediococcus pentosaceus and Cronobacter sakazakii became dominant bacterial species 17 h after fermentation commencement, while the species diversity was decreased. Our results will be a scientific basis for promoting the fermentation process of Massa Medicata Fermentata by using pure microbial cultures.


Assuntos
Medicamentos de Ervas Chinesas , Fermentação , Fungos/genética , Microbiota , Saccharomycopsis
20.
Plant Pathol J ; 35(4): 351-361, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31481858

RESUMO

In our previous study, pyrrolnitrin produced in Pseudomonas chlororaphis G05 plays more critical role in suppression of mycelial growth of some fungal pathogens that cause plant diseases in agriculture. Although some regulators for pyrrolnitrin biosynthesis were identified, the pyrrolnitrin regulation pathway was not fully constructed. During our screening novel regulator candidates, we obtained a white conjugant G05W02 while transposon mutagenesis was carried out between a fusion mutant G05ΔphzΔprn::lacZ and E. coli S17-1 (pUT/mini-Tn5Kan). By cloning and sequencing of the transposon-flanking DNA fragment, we found that a vfr gene in the conjugant G05W02 was disrupted with mini-Tn5Kan. In one other previous study on P. fluorescens, however, it was reported that the deletion of the vfr caused increased production of pyrrolnitrin and other antifungal metabolites. To confirm its regulatory function, we constructed the vfr-knockout mutant G05Δvfr and G05ΔphzΔprn::lacZΔvfr. By quantifying ß-galactosidase activities, we found that deletion of the vfr decreased the prn operon expression dramatically. Meanwhile, by quantifying pyrrolnitrin production in the mutant G05Δvfr, we found that deficiency of the Vfr caused decreased pyrrolnitrin production. However, production of phenazine-1-carboxylic acid was same to that in the wild-type strain G05. Taken together, Vfr is required for pyrrolnitrin but not for phenazine-1-carboxylic acid biosynthesis in P. chlororaphis G05.

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