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1.
Appl Microbiol Biotechnol ; 108(1): 136, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38229327

RESUMO

Livestock farms are major reservoirs of antibiotic resistance genes (ARGs) that are discharged into the environment. However, the abundance, diversity, and transmission of ARGs in duck farms and its impact on surrounding environments remain to be further explored. Therefore, the characteristics of ARGs and their bacterial hosts from duck farms and surrounding environment were investigated by using metagenomic sequencing. Eighteen ARG types which consist of 823 subtypes were identified and the majority conferred resistance to multidrug, tetracyclines, aminoglycosides, chloramphenicols, MLS, and sulfonamides. The floR gene was the most abundant subtype, followed by sul1, tetM, sul2, and tetL. ARG abundance in fecal sample was significantly higher than soil and water sample. Our results also lead to a hypothesis that Shandong province have been the most contaminated by ARGs from duck farm compared with other four provinces. PcoA results showed that the composition of ARG subtypes in water and soil samples was similar, but there were significant differences between water and feces samples. However, the composition of ARG subtypes were similar between samples from five provinces. Bacterial hosts of ARG subtypes were taxonomically assigned to eight phyla that were dominated by the Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria. In addition, some human bacterial pathogens could be enriched in duck feces, including Enterococcus faecium, Acinetobacter baumannii, and Staphylococcus aureus, and even serve as the carrier of ARGs. The combined results indicate that a comprehensive overview of the diversity and abundance of ARGs, and strong association between ARGs and bacterial community shift proposed, and benefit effective measures to improve safety of antibiotics use in livestock and poultry farming. KEY POINTS: • ARG distribution was widespread in the duck farms and surroundings environment • ARG abundance on the duck farms was significantly higher than in soil and water • Human bacterial pathogens may serve as the vectors for ARGs.


Assuntos
Antibacterianos , Patos , Animais , Antibacterianos/farmacologia , Antibacterianos/análise , Bactérias/genética , China , Resistência Microbiana a Medicamentos/genética , Fazendas , Genes Bacterianos , Solo , Água/farmacologia
2.
Ecotoxicol Environ Saf ; 250: 114492, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603487

RESUMO

Urbanization carries essential influences to ecosystem of soil bacteria in coastal cities. Comprehending the patterns and drivers of bacterial diversity are essential to understanding how soil ecosystems respond to environmental change. This study aimed to explore how soil bacterial community (SBC) response to distinct urbanization of coastal cities on composition, assembly process and potential function in Guangdong province, south China. 72 samples from 24 sample sites within 3 cities were included in the study. Soil chemical properties were analyzed, and the bacterial community were investigated by high-throughout sequencing. Proteobacteria and Acidobacteria were the main phyla. Assembly processes remained in stochastic processes and co-occurrence network of SBC kept stable, while urbanization altered SBC by influencing the dominant phyla. The indicators of communities in coastal city soils were the genera gamma_proteobacterium and beta_proteobacterium. Urbanized extent was the non-negligible factor which affected soil bacterial community, despite the total carbon was still the most vital. The impact of urbanization on bacterial communities might follow a non-linear pattern. Faprotax function prediction showed different urbanized coastal city soils share similar metabolic potential. Our study improved our understanding of the response of soil bacterial communities to urbanization in subtropical coastal cities and offered a useful strategy to monitor the ecology risk toward the soil under urbanization.


Assuntos
Ecossistema , Urbanização , Cidades , Solo/química , Microbiologia do Solo , Bactérias/genética , China
3.
BMC Oral Health ; 23(1): 115, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810012

RESUMO

PURPOSE: Mucormycosis is a type of fatal infectious disease, rarely involved in the oromaxillofacial region. This study aimed to describe a series of 7 cases with oromaxillofacial mucormycosis and to discuss the epidemiology, clinical features, and treatment algorithm thereof. METHODOLOGY: Seven patients in the author's affiliation have been treated. They were assessed and presented as per their diagnostic criteria, surgical approach, and mortality rates. Reported cases of mucormycosis originally happened in craniomaxillofacial region were synthesized through a systematic review so as to better discuss its pathogenesis, epidemiology, and management. RESULTS: Six patients had a primary metabolic disorder, and one immunocompromised patient had a history of aplastic anemia. The criteria for a positive diagnosis of invasive mucormycosis were based on clinical presentation of signs and symptoms, and a biopsy for microbiological culture and histopathologic analysis. Each patient used antifungal drugs and five of them also underwent surgical resection at the same time. Four patients died due to the unregulated spread of mucormycosis, and one patient died owing to her main disease. CONCLUSIONS: Although uncommon in clinical practice setting, mucormycosis should be of great concern in oral and maxillofacial surgery, due to the life-threatening possibility of this disease. The knowledge of early diagnosis and prompt treatment is of utmost importance for saving lives.


Assuntos
Mucormicose , Humanos , Feminino , Mucormicose/diagnóstico , Mucormicose/tratamento farmacológico , Mucormicose/microbiologia , Estudos Retrospectivos , Antifúngicos , Biópsia/efeitos adversos
4.
J Antimicrob Chemother ; 77(2): 351-355, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-34726693

RESUMO

OBJECTIVES: To determine the transmission and molecular characteristics of blaNDM-producing Escherichia coli between companion animals and their healthcare providers at veterinary clinics in Guangzhou, China. METHODS: A total of 359 samples from companion animals and their healthcare providers were collected at 14 veterinary clinics in Guangzhou, China. Genomic characteristics and clonal relationships for blaNDM-positive E. coli and complete plasmid sequences were characterized based on WGS data from combined Illumina and MinION platform reads. RESULTS: Forty-five blaNDM-positive bacteria were recovered from companion animals (n = 43) and their healthcare providers (n = 2) at 10 veterinary clinics. Overall, E. coli (73.3%, 33/45) and Klebsiella pneumoniae (13.3%, 6/45) were the most prevalent species among the seven species of blaNDM-positive bacteria. Four blaNDM variants (blaNDM-1, blaNDM-4, blaNDM-5 and blaNDM-7) were identified in 45 blaNDM-positive bacteria and blaNDM-5 was the most prevalent (77.8%, 35/45). WGS indicated that the most prevalent STs were ST405 (8/33), ST453 (6/33), ST457 (6/33) and ST410 (5/33) among the 33 blaNDM-positive E. coli isolates. Phylogenomics and PFGE analysis revealed that clonal spread of blaNDM-positive ST453 E. coli isolates between companion animals and their healthcare providers was evident. In addition, two novel IncFIB plasmids carrying blaNDM-4 (pF765_FIB and pG908_FIB) were found in this study and indicated that IS26 may promote the horizontal transmission of blaNDM between different plasmid types. CONCLUSIONS: In this study we conducted a large-scale investigation on the prevalence of blaNDM-positive E. coli isolates from companion animals and their healthcare providers and revealed the clonal spread of blaNDM-positive E. coli isolates between these two groups.


Assuntos
Escherichia coli , beta-Lactamases , Animais , Antibacterianos , China/epidemiologia , Escherichia coli/genética , Pessoal de Saúde , Humanos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Animais de Estimação , Plasmídeos , beta-Lactamases/genética
5.
Zhonghua Nan Ke Xue ; 28(11): 1006-1010, 2022 Nov.
Artigo em Zh | MEDLINE | ID: mdl-37846116

RESUMO

OBJECTIVE: To report the safety and efficacy of trans-Douglas Retzius' space-sparing robot-assisted simple prostatectomy (RSS-RASP) in the treatment of large-volume BPH. METHODS: This retrospective study included 24 cases of large-volume (>80 ml) BPH treated by trans-Douglas RSS-RASP from August 2019 to June 2021. The patients ranged in age from 55 to 80 (mean 68.5) years, with an average body mass index of 25.1 (20.5-34.9) kg/m2 , median prostate volume of 132.4 (85.6-235.7) ml, and preoperative tPSA of 10.8 (0.5-37.9) ng/ml, IPSS of 25 (3-35) and quality of life (QOL) score of 5 (3-8). Before surgery, 12 of the patients received catheterization for urinary retention, 1 underwent cystostomy, 2 were complicated with hydronephrosis, 1 had stones and diverticulum in the bladder, and 14 were excluded from the cases of PCa by prostatic biopsy. The operation time, intraoperative blood loss, hemoglobin level on the first day after surgery, blood transfusion, and intra- and postoperative complications were recorded. The patients were followed up for 3 to 21 months postoperatively. Comparisons were made before and after operation in the IPSS, maximum urinary flow rate (Qmax), postvoid residual volume (PVR), QOL score, IIEF score and Male Sexual Health Questionnaire (MSHQ) score. RESULTS: Trans-Douglas RSS-RASP was successfully completed in all the 24 cases, with a mean operation time of 175 (100-285) min, intraoperative blood loss of 200 (50-800) ml, hemoglobin decrease of 25 (4-57) g/L on the first day after surgery, postoperative drainage tube indwelling of 3 (2-7) d, and urinary catheterization of 12 (4-18) d. Six (25%) of the patients received intraoperative blood transfusion, 1 underwent transurethral electrocoagulation hemostasis 1 month after surgery because of postoperative bleeding, and 1 received transurethral resection of the cicatrical adhesive tissue of the bladder neck 12 months after surgery. No other complications occurred postoperatively. The IPSS (3 [1-7]), Qmax (19.6 [9.9-32.1] ml/s), PVR (0 [0-34.9] ml) and QOL score (2 [0-3]) of the patients were significantly improved after surgery (P < 0.05), but no statistically significant differences were observed in the IIEF (20 [19-24]) and MSHQ scores (14 [13-14]) as compared with the baseline (P > 0.05). CONCLUSION: Trans-Douglas RSS-RASP is a safe and effective minimally invasive method for the treatment of large-volume (>80 ml) BPH, which can improve the urinary function of the patient after operation.


Assuntos
Hiperplasia Prostática , Robótica , Ressecção Transuretral da Próstata , Humanos , Masculino , Idoso , Próstata/cirurgia , Próstata/patologia , Qualidade de Vida , Hiperplasia Prostática/patologia , Robótica/métodos , Perda Sanguínea Cirúrgica , Estudos Retrospectivos , Hiperplasia/complicações , Hiperplasia/patologia , Ressecção Transuretral da Próstata/métodos , Hemoglobinas , Resultado do Tratamento , Prostatectomia/métodos
6.
J Fluoresc ; 30(3): 427-435, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32314138

RESUMO

Sulforhodamine B (SRB) is widely utilized for cell staining and laser field. But its application is limited by aggregation-caused quenching (ACQ). In this work, we evaluated the use of UiO-66 and UiO-67 of Zr-based metal organic frameworks (Zr-MOFs) as the host to adsorb SRB molecules due to the high stabily and good loading capacity of Zr-MOFs. The fluorescence properties of the compounds were then discussed respectively. Due to the aperture difference between UiO-66 and UiO-67, they showed distinct fluorescence properties after loading SRB. When the concentration reaches 5 ppm, fluorescence quenching begins to occur in SRB@UiO-66, while it occurs in SRB@UiO-67 at 2 ppm. The solution of quenching phenomenon could open new avenues for the extensive use of SRB.

7.
Macromol Rapid Commun ; 41(22): e2000402, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33058422

RESUMO

As a subseries of the covalent organic framework (COF) material family, polyimide-based covalent organic framework (PI-COF) material, which has the advantages of high stability of polyimide, high specific surface area, and controllable pores of COF material, is expected to be a new type of porous material with potential applications. Although the development of PI-COF is in the early stages during the past decade, it has attracted extensive attention and is widely used in heterogeneous catalysis, gas separation, and storage fields. Therefore, this review is aiming to give a comprehensive understanding of the recent progress of PI-COFs. This article summarizes the progress of PI-COF from three aspects: controllable structure design, synthesis method, and application. First of all, under the guidance of network chemical design principles, the topology type of PI-COF and the size and shape of the formed pores are summarized in terms of different organic monomers. Then the five synthetic strategies for the synthesis of PI-COF are analyzed. Finally, the applications of PI-COF in adsorption and separation, drug delivery, solar-to-electrochemical energy storage, photocatalysis, and electrocatalyst are introduced.


Assuntos
Estruturas Metalorgânicas , Adsorção , Catálise , Sistemas de Liberação de Medicamentos , Porosidade
8.
Oral Dis ; 26(5): 998-1009, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32144839

RESUMO

OBJECTIVES: We aimed to investigate whether skeletal-specific H-type blood vessels exist in alveolar bone and how they function in alveolar bone remodeling. MATERIALS AND METHODS: H-type vessels with high expression of CD31 and Endomucin (CD31hi Emcnhi ) were immunostained in alveolar bone. Abundance and age-related changes in CD31hi Emcnhi endothelial cells (H-ECs) were detected by flow cytometry. Osteoprogenitors association with H-type vessels and bone mass were detected in tooth extraction model of alveolar bone remodeling by immunohistofluorescence and micro-CT, respectively. Transcription and expression of H-EC feature genes during in vitro Notch inhibition were measured by RT-qPCR and immunocytofluorescence. RESULTS: We verified that H-type vessels existed in alveolar bone, the abundance of which was highest at infancy age, then decreased but maintained a constant level during aging. In tooth extraction model, H-ECs significantly increased with concomitant perivascular accumulation of Runx2+ osteoprogenitors and gradually augmentation of bone mass. Notch inhibition of in vitro cultured H-ECs resulted in decreased expression levels of Emcn and hes1, but not Pecam1 or Kdr genes, with decreased expression levels of H-EC numbers, accordingly. CONCLUSIONS: The present study suggests that H-type vessels promote osteogenesis during alveolar bone remodeling. Notch signaling pathway regulates expression of Emcn and possibly determines fate and functions of alveolar H-ECs.


Assuntos
Remodelação Óssea , Células Endoteliais , Osteogênese , Extração Dentária , Animais , Camundongos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética
9.
Mar Drugs ; 18(12)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322296

RESUMO

Fucoxanthin is a natural carotenoid derived mostly from many species of marine brown algae. It is characterized by small molecular weight, is chemically active, can be easily oxidized, and has diverse biological activities, thus protecting cell components from ROS. Fucoxanthin inhibits the proliferation of a variety of cancer cells, promotes weight loss, acts as an antioxidant and anti-inflammatory agent, interacts with the intestinal flora to protect intestinal health, prevents organ fibrosis, and exerts a multitude of other beneficial effects. Thus, fucoxanthin has a wide range of applications and broad prospects. This review focuses primarily on the latest progress in research on its pharmacological activity and underlying mechanisms.


Assuntos
Anti-Inflamatórios/farmacologia , Fármacos Antiobesidade/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Phaeophyceae , Xantofilas/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Fármacos Antiobesidade/isolamento & purificação , Antineoplásicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Estabilidade de Medicamentos , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Phaeophyceae/metabolismo , Xantofilas/isolamento & purificação
10.
Nanotechnology ; 30(24): 245707, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-30836337

RESUMO

The transport of water through carbon nanotubes (CNTs) is now of great importance in bionanotechnology and of considerable interest for potential nanofluidic applications. In this paper, we show by molecular dynamics simulations that the permeation of single-file water molecules through a CNT can be significantly improved by means of tuning the direction of pressure difference, i.e. introducing an additional lateral pressure to the longitudinal one. The water flow exhibits an interesting maximum behavior with the change of lateral pressure, deciphered by the breakdown of single-file water chain inside the CNT. The translocation time decreases monotonously with the increase of lateral pressure and exhibits a clear bifurcation due to the longitudinal pressure, corresponding to the flow enhancement. Therefore, the lateral pressure will increase the difficulty for water entering, while promotes the water conduction inside the CNT, whose competition ultimately leads to the flow maximum behaviors. Along with the water reducing inside the CNT, the CNT switches between the filling and empty states with the unique distributions of water dipole orientation, density and H-bond number. Our results indicate that tuning the direction of pressure difference should be a significant new strategy for enhancing the water permeability, where the key lies in the breakdown of single-file water chain and are thus insightful for future studies.

11.
Sheng Li Xue Bao ; 71(3): 454-462, 2019 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-31218336

RESUMO

Neural stem cell therapy, as a new therapeutic method for neural diseases, has aroused a wide concern for over 20 years since neural stem cells were first found in 1992. Ischemic stroke is highly concerned because of its high incidence, mortality and disability rates. Because the brain has a limited ability to repair itself, to improve neural function and promote neural regeneration may help to prevent occurrence and development of neurological diseases. It is noteworthy that some stroke patients showed an ability to repair brain several months after the stroke happened, suggesting an existence of endogenous nerve repair in these patients. The research advances in functions of endogenous neural stem cells in neural regeneration and the related regulators after ischemic stroke are summarized in this review to provide new views of the mechanism of neural functional recovery after ischemic stroke.


Assuntos
Isquemia Encefálica/terapia , Regeneração Nervosa , Células-Tronco Neurais/citologia , Acidente Vascular Cerebral/terapia , Humanos
12.
Nanotechnology ; 29(22): 225706, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29547396

RESUMO

Graphene is a versatile 2D material and attracts an increasing amount of attention from a broad scientific community, including novel nanofluidic devices. In this work, we use molecular dynamics simulations to study the pressure driven water transport through graphene layers, focusing on the pore size homogeneity, realized by the arrangement of two pore sizes. For a given layer number, we find that water flux exhibits an excellent linear behavior with pressure, in agreement with the prediction of the Hagen-Poiseuille equation. Interestingly, the flux for concentrated pore size distribution is around two times larger than that of a uniform distribution. More surprisingly, under a given pressure, the water flux changes in an opposite way for these two distributions, where the flux ratio almost increases linearly with the layer number. For the largest layer number, more distributions suggest the same conclusion that higher water flux can be attained for more concentrated pore size distributions. Similar differences for the water translocation time and occupancy are also identified. The major reason for these results should clearly be due to the hydrogen bond and density profile distributions. Our results are helpful to delineate the exquisite role of pore size homogeneity, and should have great implications for the design of high flux nanofluidic devices and inversely the detection of pore structures.

13.
BMC Infect Dis ; 17(1): 371, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28558660

RESUMO

BACKGROUND: The clonal spread of multiple drug-resistant Acinetobacter baumannii is an emerging problem in China. We analysed the molecular epidemiology of Acinetobacter baumanni isolates at three teaching hospitals and investigated the risk factors, clinical features, and outcomes of hospital-acquired pneumonia caused by extensive drug-resistant Acinetobacter baumannii (XDRAB) infection in Guangzhou, China. METHODS: Fifty-two A. baumannii isolates were collected. Multilocus sequence typing (MLST) was used to assess the genetic relationships among the isolates. The bla OXA-51-like gene was amplified using polymerase chain reaction (PCR) and sequencing. The resistance phenotypes were determined using the disc diffusion method. A retrospective case-control study was performed to determine factors associated with XDRAB pneumonia. RESULTS: Most of the 52 A. baumannii isolates (N = 37, 71.2%) were collected from intensive care units (ICUs). The respiratory system was the most common bodily site from which A. baumannii was recovered (N = 45, 86.5%). Disc diffusion classified the isolates into 17 multidrug-resistant (MDR) and 35 extensively drug-resistant (XDR) strains. MLST grouped the A. baumannii isolates into 5 existing sequence types (STs) and 7 new STs. ST195 and ST208 accounted for 69.2% (36/52) of the isolates. The clonal relationship analysis showed that ST195 and ST208 belonged to clonal complex (CC) 92. According to the sequence-based typing (SBT) of the bla OXA-51-like gene, 51 A. baumannii isolates carried OXA-66 and the rest carried OXA-199. There were no significant differences with respect to the resistance phenotype between the CC92 and non-CC92 strains (P = 0.767). The multivariate analysis showed that the APACHE II score, chronic obstructive pulmonary disease (COPD) and cardiac disease were independent risk factors for XDRAB pneumonia (P < 0.05). The mortality rate of XDRAB pneumonia was high (up to 42.8%), but pneumonia caused by XDRAB was not associated with in-hospital mortality (P = 0.582). CONCLUSIONS: ST195 may be the most common ST in Guangzhou, China, and may serve as a severe epidemic marker. SBT of bla OXA-51-like gene variants may not result in sufficient dissimilarities to type isolates in a small-scale, geographically restricted study of a single region. XDRAB pneumonia was strongly related to systemic illnesses and the APACHE II score but was not associated with in-hospital mortality.


Assuntos
Infecções por Acinetobacter/mortalidade , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/genética , Pneumonia Bacteriana/mortalidade , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/patogenicidade , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , China/epidemiologia , Farmacorresistência Bacteriana/genética , Feminino , Mortalidade Hospitalar , Hospitais de Ensino , Humanos , Unidades de Terapia Intensiva , Masculino , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/epidemiologia , Doença Pulmonar Obstrutiva Crônica/microbiologia , Doença Pulmonar Obstrutiva Crônica/mortalidade , Estudos Retrospectivos , Fatores de Risco , beta-Lactamases/genética
14.
Phys Chem Chem Phys ; 19(33): 22406-22416, 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28808710

RESUMO

Nanoparticles are highly versatile and exhibit broad applications in tuning material properties. Herein, we show through molecular dynamics simulations the possibility of a nanometer water pump, driven by the motion of nanoparticles (NPs) on a membrane surface. Surprisingly, considerable net water flux can be induced through a carbon nanotube (CNT) that is perpendicular to the NP motion. The water transport can occur in a highly controllable fashion, not only by using a single NP with different forces, but also by varying the CNT length or the NP number. Specifically, for a single NP, the water flow and flux are found to increase linearly with an increase in force, following the same behavior of NP velocity. Inversely, the water translocation time exhibits a linear decrease. We further revealed the unique relation between the water flow and occupancy divided by the translocation time. The CNT length can significantly screen the thermal fluctuation of an outside water reservoir, leading to an increase in the water flux and subsequent unidirectional transport. More interestingly, under moderate force, the water flow and flux demonstrate maximum behaviors with an increase in NP number, co-determined by the NP velocity and water occupancy. The maximum location shifts to the lower NP number region for a larger force. We also identify two CNT states that correspond to low water flow. Our results provide a significant new method to pump water molecules through a CNT channel, which is helpful for the design of controllable nanofluidic devices.

15.
J Chem Phys ; 146(20): 204902, 2017 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-28571349

RESUMO

Understanding the water permeation through a cell membrane is of primary importance for biological activities and a key step to capture its shape transformation in salt solution. In this work, we reveal the dynamical behaviors of osmotically driven transport of water molecules across a vesicle membrane by molecular dynamics simulations. Of particular interest is that the water transport in and out of vesicles is highly distinguishable given the osmotic force are the same, suggesting an asymmetric osmotic transportation. This asymmetric phenomenon exists in a broad range of parameter space such as the salt concentration, temperature, and vesicle size and can be ascribed to the similar asymmetric potential energy of lipid-ion, lipid-water, lipid-solution, lipid-lipid, and the lipid-lipid energy fluctuation. Specifically, the water flux has a linear increase with the salt concentration, similar to the prediction by Nernst-Planck equation or Fick's first law. Furthermore, due to the Arrhenius relation between the membrane permeability and temperature, the water flux also exhibits excellent Arrhenius dependence on the temperature. Meanwhile, the water flux shows a linear increase with the vesicle surface area since the flux amount across a unit membrane area should be a constant. Finally, we also present the anonymous diffusion behaviors for the vesicle itself, where transitions from normal diffusion at short times to subdiffusion at long times are identified. Our results provide significant new physical insights for the osmotic water permeation through a vesicle membrane and are helpful for future experimental studies.


Assuntos
Lipídeos/química , Simulação de Dinâmica Molecular , Água/química , Pressão Osmótica
16.
Am J Ther ; 23(6): e1680-e1689, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26938752

RESUMO

The aim of this study was to investigate whether ulinastatin (UTL) has protective effects on perioperative proinflammatory cytokines and lung injury in cardiopulmonary bypass (CPB) patients. The study included 60 patients undergoing CPB who were randomly divided into a UTL group and a control group. Blood routine examination and inflammatory cytokines concentrations were detected after anesthetic induction (T1), immediately after aortic valve opening (T2), and 4 (T3) and 24 (T4) hours after weaning from CPB. Flow cytometry was used to detect TLR4 and HSP70 expressions. Arterial blood gas and respiratory function were analyzed at the same time points. Compared with the control group, the levels of IL-2, IL-8, TNF-α, NE, TLR4, PA - aDO2, and RI at T2 were significantly lower, whereas HSP70, PaO2, OI, Cd, and Cs were higher in the UTL group (all P < 0.05). Relative to the control group at T3, white blood cell count, TLR4, IL-2, IL-6, IL-8, TNF-α, NE, and RI decreased significantly, whereas IL-10, HSP70, PaO2, OI, and Cs increased in the UTL group (all P < 0.05). At T4, IL-2, IL-6, IL-8, TNF-α, TLR4, and PaCO2 in the UTL group were significantly lower, and PaO2, IL-10, HSP70, and Cs were higher than in the control group (all P < 0.05). Our data show strong evidence that UTL suppresses proinflammatory cytokine elevation and upregulates release of anti-inflammatory mediators, reducing pulmonary injury and improving pulmonary function after CPB.


Assuntos
Lesão Pulmonar Aguda/fisiopatologia , Ponte Cardiopulmonar/métodos , Citocinas/biossíntese , Glicoproteínas/farmacologia , Mediadores da Inflamação/metabolismo , Período Perioperatório , Adolescente , Adulto , Idoso , Gasometria , Citocinas/sangue , Feminino , Citometria de Fluxo , Humanos , Inflamação/fisiopatologia , Mediadores da Inflamação/sangue , Interleucinas/biossíntese , Interleucinas/sangue , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Fatores de Tempo , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
17.
Phys Chem Chem Phys ; 17(5): 3115-22, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25516239

RESUMO

Current rectification is found in oxygen-substituted zigzag graphyne nanoribbon/hydrogen-terminated zigzag graphene nanoribbon heterostructure junctions, from the application of nonequilibrium Green's function formalism combined with density functional theory. This behavior could be tuned by varying the number and location of oxygen atoms in the zigzag graphyne nanoribbon parts, and the rectification direction could be reversed due to the parity limitation tunneling effect. Moreover, an obvious negative differential resistance behavior is found and may be explained by two different mechanisms.

18.
Nano Lett ; 14(6): 3661-7, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24844280

RESUMO

Here, we show a novel solid-solid-vapor (SSV) growth mechanism whereby epitaxial growth of heterogeneous semiconductor nanowires takes place by evaporation-induced cation exchange. During heating of PbSe-CdSe nanodumbbells inside a transmission electron microscope (TEM), we observed that PbSe nanocrystals grew epitaxially at the expense of CdSe nanodomains driven by evaporation of Cd. Analysis of atomic-resolution TEM observations and detailed atomistic simulations reveals that the growth process is mediated by vacancies.

19.
J Hazard Mater ; 472: 134387, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38723479

RESUMO

Microplastics (MPs) are distributed widely in the ocean surface waters and sediments. Increasing MPs contamination in intertidal zone profoundly impacts microbial ecosystem services and biogeochemical process. Little is known about the response of tidal sediment microbiome to MPs. We conducted a 30-day laboratory microcosm study using five polymers (PE, PBS, PC, PLA and PET) at three concentrations (1 %, 2 % and 5 %, w/w). High throughput sequencing of 16 S rRNA, qPCR and enzyme activity test were applied to demonstrate the response of microbial community and nitrogen cycling functional genes to MPs. MPs reduced the microbial alpha diversity and the microbial dissimilarity while the effects of PLA-MPs were concentration dependent. LEfSe analysis indicated that the Proteobacteria predominated for all MP treatments. Mantel's test, RDA and correlation analysis implied that pH may be the key environmental factor for causing microbial alterations. MPs enhanced nitrogen fixation in tidal sediment. PLA levels of 1 % but not 5 % produced the most significant effects in nitrogen cycling functional microbiota and genes. PLS-PM revealed that impacts of MPs on tidal sediment microbial communities and nitrogen cycling were dominated by indirect effects. Our study deepened understanding and filled the knowledge gap of MP contaminants affecting tidal sediment microbial nitrogen cycling.


Assuntos
Exposição Ambiental , Microbiota , Microplásticos , Ciclo do Nitrogênio , Polímeros , Microplásticos/química , Microplásticos/toxicidade , Polímeros/química , Polímeros/toxicidade , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Ciclo do Nitrogênio/efeitos dos fármacos , Ciclo do Nitrogênio/genética , Microbiota/efeitos dos fármacos , Microbiota/genética , Biodiversidade , Concentração de Íons de Hidrogênio , Ondas de Maré
20.
Quant Imaging Med Surg ; 14(2): 1844-1859, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415114

RESUMO

Background: Although atrial high-rate episode (AHRE) and atrial fibrillation (AF) cannot entirely be identical, recent studies suggest AHRE is linked to AF development and shares some characteristics with AF regarding thromboembolism. At present, there is still lack of predictive indicators for AHRE and diagnostic methods and clinical indicators for AHRE in patients without cardiac implantable electronic device (CIED). The aim of this study was thus to explore the relationship between AHRE and left atrial (LA) strain parameters with the goal of identifying high-risk populations of AHRE by LA strain characteristics. Methods: From February 2022 to May 2023, a total of 105 CIED patients were enrolled and divided into two groups based on whether AHRE had occurred: AHRE (-) group (n=65) and AHRE (+) group (n=40). Real-time three-dimensional echocardiography (RT-3DE) technique was used to obtain the LA time-volume curve. The collected dynamic images were analyzed on the Echopac 204 workstation to obtain the parameters of LA. The four-dimensional automatic LA quantitative analysis (4D Auto LAQ) technology was used to analyze the LA strain parameters: LA reservoir longitudinal strain (LASr), LA conduit longitudinal strain (LAScd), LA contraction longitudinal strain (LASct), LA reservoir circumferential strain (LASr-c), LA conduit circumferential strain (LAScd-c), LA contraction circumferential strain (LASct-c). Correlation analysis was carried out using Binary logistic regression analysis. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the diagnostic performance of LASct in AHRE. Results: Body surface area (BSA) [odds ratio (OR) =8.34, 95% confidence interval (CI): 1.32-72.30, P=0.037], LASct (OR =1.20, 95% CI: 1.05-1.39, P=0.013) and LA end-systolic volume (LAESV) (OR =1.02, 95% CI: 1.00-1.04, P=0.023) were the influencing factors of AHRE. Only LASct (OR =1.18, 95% CI: 1.01-1.38, P=0.041) was found to be an independent influencing factor of AHRE. This result remained significant after adjusting for age, sex, hypertension, diabetes, and stroke history. The ROC curve showed that the cut-off for predicting AHRE was LASct =-4.125% with sensitivity of 37.5% and specificity of 87.7%. Conclusions: This cross-sectional study found that decreased LASct (absolute value) is an independent risk factor for the AHRE and has diagnostic efficacy in certain degree for the occurrence of AHRE.

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