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1.
Materials (Basel) ; 17(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38473520

RESUMO

Isocyanate esters are widely recognized for their superior curing capabilities. Leveraging this attribute, the current research formulated a modified cold-mixed asphalt blend using 4,4'-methylene diphenyl diisocyanate (MDI). Tests and analyses of the MDI-modified asphalt with varying inclusion percentages of MDI revealed that a mixture containing 15% rock asphalt and 15% MDI-modified asphalt exhibited a more balanced, comprehensive performance. We also conducted an examination of the role and properties of MDI in asphalt modification using molecular dynamics simulations. The cold-curing properties of MDI-modified asphalt as compared to petroleum asphalt were evaluated based on its density, free volume analysis, cohesive energy density, and glass transition temperature. Implementing the LB-13 gradation-a cold-mixed asphalt gradation with a nominal particle size of 13.2 mm recommended by Chinese specifications-we prepared MDI-modified cold-mixed asphalt and carried out analyses of its mechanical characteristics, high-temperature performance, and water damage resistance. The results demonstrated that MDI-modified asphalt showcases excellent ductility, flexibility, and aging resistance, surpassing the performance of petroleum asphalt. The stability, high-temperature rutting, and water damage resistance of the MDI-modified cold-mixed asphalt exceeded the requirements for hot-mixed asphalt. This research provides theoretical and experimental support for isocyanate ester applications in asphalt engineering, presenting significant value for practical engineering applications.

2.
Materials (Basel) ; 16(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37297320

RESUMO

Pavement materials such as asphalt mixtures, granular aggregates and soils exhibit complex material properties and engineering performance under external loading and environmental conditions [...].

3.
Artigo em Inglês | MEDLINE | ID: mdl-36330462

RESUMO

Recombinant herpes simplex virus strains can be constructed by several methods, including homologous recombination, bacterial artificial chromosome manipulation, and yeast genetic methods. Homologous recombination may have the advantage of introducing fewer genetic alterations in the viral genome, but the low level of recombinants can make this method more time consuming if there is no screen or selection. In this study we used complementing cell lines that express Cas9 and guide RNAs targeting the parental virus to rapidly generate recombinant viruses. Analysis of the progeny viruses indicated that CRISPR-Cas9 both promoted recombination to increase recombinant viruses and selected against parental viruses in the transfection progeny viruses. This approach can also be used to enrich for recombinants made by any of the current methods.

4.
Cell Rep ; 40(1): 111033, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35793624

RESUMO

The immune response of brain cells to invading bacteria in vivo and the mechanism used by pathogenic bacteria to escape brain immune surveillance remain largely unknown. It is believed that microglia eliminate bacteria by phagocytosis based on in vitro data. Here we find that a small percentage of microglia in the brain engulf neonatal meningitis-causing Escherichia coli (NMEC), but more microglia are activated to produce tumor necrosis factor alpha (TNFα), which activates astrocytes to secrete complement component 3 (C3) involved in anti-bacterial activity. To evade anti-bacterial activity of the immune system, NMEC senses low concentration of threonine in cerebrospinal fluid (CSF) to down-modulate the expression of flagellin and reduce microglial TNFα and astrocyte C3 production. Our findings may help develop strategies for bacterial meningitis treatment.


Assuntos
Astrócitos , Microglia , Astrócitos/metabolismo , Bactérias/metabolismo , Encéfalo/metabolismo , Flagelina/metabolismo , Flagelina/farmacologia , Humanos , Recém-Nascido , Microglia/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
mBio ; 12(4): e0046321, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34340542

RESUMO

Oropouche virus (OROV) infection of humans is associated with a debilitating febrile illness that can progress to meningitis or encephalitis. First isolated from a forest worker in Trinidad and Tobago in 1955, the arbovirus OROV has since been detected throughout the Amazon basin with an estimated 500,000 human infections over 60 years. Like other members of the family Peribunyaviridae, the viral genome exists as 3 single-stranded negative-sense RNA segments. The medium-sized segment encodes a viral glycoprotein complex (GPC) that is proteolytically processed into two viral envelope proteins, Gn and Gc, responsible for attachment and membrane fusion. There are no therapeutics or vaccines to combat OROV infection, and we have little understanding of protective immunity to infection. Here, we generated a replication competent chimeric vesicular stomatitis virus (VSV), in which the endogenous glycoprotein was replaced by the GPC of OROV. Serum from mice immunized by intramuscular injection with VSV-OROV specifically neutralized wild-type OROV, and using peptide arrays we mapped multiple epitopes within an N-terminal variable region of Gc recognized by the immune sera. VSV-OROV lacking this variable region of Gc was also immunogenic in mice producing neutralizing sera that recognize additional regions of Gc. Challenge of both sets of immunized mice with wild-type OROV shows that the VSV-OROV chimeras reduce wild-type viral infection and suggest that antibodies that recognize the variable N terminus of Gc afford less protection than those that target more conserved regions of Gc. IMPORTANCE Oropouche virus (OROV), an orthobunyavirus found in Central and South America, is an emerging public health challenge that causes debilitating febrile illness. OROV is transmitted by arthropods, and increasing mobilization has the potential to significantly increase the spread of OROV globally. Despite this, no therapeutics or vaccines have been developed to combat infection. Using vesicular stomatitis (VSV) as a backbone, we developed a chimeric virus bearing the OROV glycoproteins (VSV-OROV) and tested its ability to elicit a neutralizing antibody response. Our results demonstrate that VSV-OROV produces a strong neutralizing antibody response that is at least partially targeted to the N-terminal region of Gc. Importantly, vaccination with VSV-OROV reduces viral loads in mice challenged with wild-type virus. These data provide novel evidence that targeting the OROV glycoproteins may be an effective vaccination strategy to combat OROV infection.


Assuntos
Infecções por Bunyaviridae/prevenção & controle , Genoma Viral , Orthobunyavirus/genética , Vesiculovirus/genética , Vesiculovirus/imunologia , Proteínas do Envelope Viral/genética , Animais , Anticorpos Neutralizantes , Infecções por Bunyaviridae/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estomatite Vesicular/virologia , Replicação Viral
6.
Pathol Oncol Res ; 27: 602726, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257561

RESUMO

Genotyping epidermal growth factor receptor (EGFR) gene in patients with advanced non-small cell lung cancers (NSCLC) is essential for identifying those patients who may benefit from targeted therapies. Systemically evaluating EGFR mutation detection rates of different methods currently used in clinical setting will provide valuable information to clinicians and laboratory scientists who take care of NSCLC patients. This study retrospectively reviewed the EGFR data obtained in our laboratory in last 10 years. A total of 21,324 NSCLC cases successfully underwent EGFR genotyping for clinical therapeutic purpose, including 5,244 cases tested by Sanger sequencing, 13,329 cases tested by real-time PCR, and 2,751 tested by next-generation sequencing (NGS). The average EGFR mutation rate was 45.1%, with 40.3% identified by Sanger sequencing, 46.5% by real-time PCR and 47.5% by NGS. Of these cases with EGFR mutations identified, 93.3% of them harbored a single EGFR mutation (92.1% with 19del or L858R, and 7.9% with uncommon mutations) and 6.7% harbored complex EGFR mutations. Of the 72 distinct EGFR variants identified in this study, 15 of them (single or complex EGFR mutations) were newly identified in NSCLC. For these cases with EGFR mutations tested by NGS, 65.3% of them also carried tumor-related variants in some non-EGFR genes and about one third of them were considered candidates of targeted drugs. NGS method showed advantages over Sanger sequencing and real-time PCR not only by providing the highest mutation detection rate of EGFR but also by identifying actionable non-EGFR mutations with targeted drugs in clinical setting.


Assuntos
Povo Asiático/genética , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Laboratórios/normas , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/genética , China/epidemiologia , Receptores ErbB/genética , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Adulto Jovem
7.
Virology ; 559: 165-172, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33930819

RESUMO

SARS coronavirus 1 (SARS-CoV-1) causes a respiratory infection that can lead to acute respiratory distress characterized by inflammation and high levels of cytokines in the lung tissue. In this study we constructed a herpes simplex virus 1 replication-defective mutant vector expressing SARS-CoV-1 spike protein as a potential vaccine vector and to probe the effects of spike protein on host cells. The spike protein expressed from this vector is functional in that it localizes to the surface of infected cells and induces fusion of ACE2-expressing cells. In immunized mice, the recombinant vector induced antibodies that bind to spike protein in an ELISA assay and that show neutralizing activity. The spike protein expressed from this vector can induce the expression of cytokines in an ACE2-independent, MyD88-dependent process. These results argue that the SARS-CoV-1 spike protein intrinsically activates signaling pathways that induce cytokines and contribute directly to the inflammatory process of SARS.


Assuntos
Anticorpos Neutralizantes/imunologia , Herpesvirus Humano 1/genética , Imunidade Inata , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Fusão Celular , Linhagem Celular , Citocinas/imunologia , Vetores Genéticos , Humanos , Camundongos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Transdução de Sinais , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/imunologia
8.
Front Microbiol ; 11: 574833, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329434

RESUMO

Escherichia coli K1 is the leading cause of meningitis in newborns. Understanding the molecular basis of E. coli K1 pathogenicity will help develop treatment of meningitis and prevent neurological sequelae. E. coli K1 replicates in host blood and forms a high level of bacteremia to cause meningitis in human. However, the mechanisms that E. coli K1 employs to sense niche signals for survival in host blood are poorly understood. We identified one intergenic region in E. coli K1 genome that encodes a novel small RNA, sRNA-17. The expression of sRNA-17 was downregulated by ArcA in microaerophilic blood. The ΔsRNA-17 strain grew better in blood than did the wild-type strain and enhanced invasion frequency in human brain microvascular endothelial cells. Transcriptome analyses revealed that sRNA-17 regulates tens of differentially expressed genes. These data indicate that ArcA downregulates the sRNA-17 expression to benefit bacterial survival in blood and penetration of the blood-brain barrier. Our findings reveal a signaling mechanism in E. coli K1 for host adaptation.

9.
Exp Ther Med ; 19(4): 3143-3149, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32256802

RESUMO

The incidence of gastric hyperplastic polyps (HPs) has been on the rise in recent years. The contribution of Helicobacter pylori infection to this trend has remained to be elucidated. The present study aimed to explore the association between HPs and H. pylori in China, an area with a high infection rate of H. pylori. In order to study trends of HPs and H. pylori infection over the past decades, cases encountered from 2009 to 2018 were assessed and a total of 109,150 consecutive patients who underwent esophagogastroduodenoscopy at Qingdao Municipal Hospital (Qingdao, China) were enrolled. The incidence of HPs and the prevalence of H. pylori were determined and their correlation was explored. Gastric HPs were detected in 1,497 patients (1.6%) who received gastric biopsies. The incidence of HPs exhibited a rising trend, with a ~4-fold increase in the annual detection rate from 2009 to 2018. The prevalence of H. pylori infection was inversely associated with the prevalence of HPs (adjusted odds ratio, 0.66). The prevalence of H. pylori in the examined cohort decreased with time (r=-0.76, P=0.011). The decreasing trend of H. pylori infection was negatively correlated with the rising trend of HPs (r=-0.64, P=0.048), further indicating an inverse association between them. The difference in the prevalence of HPs between H. pylori-negative and -positive patients increased with age (r=0.80, P=0.018). The age-associated increase was slower in H. pylori-infected patients. The decline in H. pylori infection with time appeared to not be associated with the birth cohort effect, suggesting the decline was not caused by exposure to environmental factors during an early period of life. The present results indicated that the incidence of gastric HPs increased with the decline in H. pylori infection, demonstrating an inverse association between the occurrence of HPs and the infection.

10.
Oncol Lett ; 16(3): 3917-3922, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30128008

RESUMO

Circulating follicular helper T (cTfh) cells are a novel subset of cluster of differentiation (CD)4+ helper T cells. Interleukin (IL)-21 and C-X-C motif chemokine ligand (CXCL)13 are the principal effectors and chemotactic regulatory factors of Tfh. However, the roles of IL-21 and CXCL13 in gastric cancer have not yet been completely elucidated. The aim of the present study was to investigate the distribution of cTfh cells, and the expression of IL-21 and CXCL13 in patients with gastric cancer was evaluated in order to ascertain the significance and potential mechanisms of these effectors in gastric cancer. A total of 50 patients with gastric cancer were enrolled as the study subjects, with 30 healthy individuals selected as controls. The percentage of cTfh cells (cTfh%) in the peripheral blood was calculated using flow cytometry. They are identified in the present study as CD4+ chemokine C-X-C receptor (CXCR)5+ inducible T cell co-stimulator (ICOS)+ cells. The serum levels of IL-21 and CXCL13 were determined by ELISA. The cTfh% in the peripheral blood and the concentration of IL-21 and CXCL13 in the serum were significantly higher in patients with gastric cancer compared with the control group. cTfh% was significantly higher in patients with lymph node metastasis, Tumor-Node-Metastasis (TNM) stage III-IV and low differentiation. The concentrations of IL-21 and CXCL13 in patients with lymph node metastasis and/or TNM III-IV were significantly higher than in those without lymph node metastasis or with TNM I-II. There was a positive correlation between cTfh%/CXCL13 and IL-21/CXCL13, while there was no correlation between cTfh%/IL-21. cTfh cells and associated factors (IL-21/CXCL13) may be involved in the development and progression of gastric cancer. There may be mutual regulation among cTfh cells, IL-21 and CXCL13.

11.
Turk J Gastroenterol ; 29(1): 45-51, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29391307

RESUMO

BACKGROUND/AIMS: The function of regulatory T cells (Treg) and helper T cells 17 (Th17) related indexes, such as interleukin (IL)-6, IL-17, transforming growth factor (TGF)-ß1, and forkhead box protein 3(FoxP3) in gastric adenocarcinoma tissues remains undefined. We investigated and analyzed the relevance of the proteins with the clinicopathological characteristics and the interactions among them in gastric cancer. MATERIALS AND METHODS: A total 68 gastric cancer patients and 40 healthy controls were enrolled. Immunohistochemistry (IHC) as well as quantitative real-time reverse transcription- polymerase chain reaction (RT-PCR) was used to determine the expression levels of IL-6, TGF-ß1, IL-17, and FoxP3 in the prepared tissues. Statistical analysis included ANOVA and chi-square test. RESULTS: The expression levels of IL-6, IL-17, FoxP3, and TGF-ß1 had significantly increased in cancer tissues compared to controls. Clinical staging of gastric cancer were correlated with the rise of IL-6, IL-17, FoxP3, and TGF-ß1 levels expressed in cancer tissues. The expression level of TGF-ß1 and IL-6 was positively related to that of IL-17 and FoxP3, similar to FoxP3 and IL-17 in gastric cancer tissues. CONCLUSION: IL-6, TGF-ß1, FoxP3, and IL-17 may promote the progression of gastric cancer individually or jointly and have complex interactions.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Neoplasias Gástricas/genética , Fator de Crescimento Transformador beta1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Linfócitos T Reguladores/metabolismo , Células Th17/metabolismo
12.
World J Gastroenterol ; 22(42): 9437-9444, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27895432

RESUMO

AIM: To investigate the prevalence of depression and anxiety in patients with chronic digestive system diseases. METHODS: A total of 1736 patients with chronic digestive system diseases were included in this cross-sectional study, including 871 outpatients and 865 in-patients. A self-designed General Information for Patients of the Department of Gastroenterology of General Hospitals questionnaire was used to collect each patient's general information, which included demographic data (including age, sex, marital status, and education) and disease characteristics (including major diseases, disease duration, principal symptoms, chronic pain, sleep disorder, and limited daily activities). RESULTS: The overall detection rate was 31.11% (540/1736) for depression symptoms alone, 27.02% (469/1736) for anxiety symptoms alone, 20.68% (359/1736) for both depression and anxiety symptoms, and 37.44% (650/1736) for either depression or anxiety symptoms. Subjects aged 70 years or above had the highest detection rate of depression (44.06%) and anxiety symptoms (33.33%). χ2 trend test showed: the higher the body mass index (BMI), the lower the detection rate of depression and anxiety symptoms (χ2trend = 13.697, P < 0.001; χ2trend = 9.082, P = 0.003); the more severe the limited daily activities, the higher the detection rate of depression and anxiety symptoms (χ2trend = 130.455, P < 0.001, χ2trend = 108.528, P < 0.001); and the poorer the sleep quality, the higher the detection rate of depression and anxiety symptoms (χ2trend = 85.759, P < 0.001; χ2trend = 51.969, P < 0.001). Patients with digestive system tumors had the highest detection rate of depression (57.55%) and anxiety (55.19%), followed by patients with liver cirrhosis (41.35% and 48.08%). Depression and anxiety symptoms were also high in subjects with comorbid hypertension and coronary heart disease. CONCLUSION: Depression and anxiety occur in patients with tumors, liver cirrhosis, functional dyspepsia, and chronic viral hepatitis. Elderly, divorced/widowed, poor sleep quality, and lower BMI are associated with higher risk of depression and anxiety.


Assuntos
Ansiedade/epidemiologia , Depressão/epidemiologia , Doenças do Sistema Digestório/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ansiedade/diagnóstico , Ansiedade/fisiopatologia , Ansiedade/psicologia , Índice de Massa Corporal , Distribuição de Qui-Quadrado , China/epidemiologia , Doença Crônica , Comorbidade , Estudos Transversais , Depressão/diagnóstico , Depressão/fisiopatologia , Depressão/psicologia , Doenças do Sistema Digestório/diagnóstico , Doenças do Sistema Digestório/fisiopatologia , Doenças do Sistema Digestório/psicologia , Feminino , Nível de Saúde , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Sono , Inquéritos e Questionários , Adulto Jovem
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 449-53, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-27209748

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are listed as the priority pollutants. It is difficult to resolve effectively the peaks of PAHs by conventional one-dimensional fluorescence spectroscopy due to its low content and the overlapping fluorescence three mixed ystems and a total of 27 samples, are to be prepared with different concentrations of three PAHs. Concentrations of three PAHS are monotonically increasing or decreasing in each mixed system. Then the 2D fluorescence correlation spectrum of each mixed systems will be calculated under the perturbation of the concentration of anthracene, phenanthrene and pyrene in solution. There are seven strong autopeaks at 425, 402, 381, 373, 365, 393 and 347 nm in synchronous 2D correlation spectrum. The fluorescence peak of phenanthrene at 347 nm is uncovered in three mixed systems, so the band at 347 nm is to be used as clues for further assignment. According to positive or negative cross peaks at 347 nm in synchronous 2D correlation spectrum, we can know that the peaks at 402, 381, 425 and 452 nm are assigned to anthracene, the peaks at 373 and 393 nm are assigned to pyrene, and the peaks at 365, 356 and 347 nm are assigned to phenanthrene. The fluorescence peak of phenanthrene at 385 nm is shown in asynchronous 2D correlation spectrum; it means the spectral resolution of asynchronous spectrum is better than the synchronous spectrum. The results are that it is feasible to analyze serious overlapping multi-component PAHs using two-dimensional fluorescence correlation spectroscopy, which can be extended to the detection of other pollutants in the air.

14.
PLoS One ; 8(2): e57224, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23468943

RESUMO

Genital herpes is a sexually transmitted infection (STI) caused by herpes simplex virus 2 (HSV-2) and to a lesser extent herpes simplex virus 1 (HSV-1). Infection by HSV-2 is life-long and is associated with significant cost to healthcare systems and social stigma despite the highly prevalent nature of the disease. For instance, the proportion of HSV-2 seropositive to seronegative adults is approximately 1 in 5 in the US and greater than 4 in 5 in some areas of sub-Saharan Africa. The replication-defective vaccine strain virus dl5-29 was re-derived using cells appropriate for GMP manufacturing and renamed ACAM529. Immunization with dl5-29 was previously reported to be protective both in mice and in guinea pigs, however these studies were performed with vaccine that was purified using methods that cannot be scaled for manufacturing of clinical material. Here we describe methods which serve as a major step towards preparation of ACAM529 which may be suitable for testing in humans. ACAM529 can be harvested from infected cell culture of the trans-complementing cell line AV529 clone 19 (AV529-19) without mechanical cell disruption. ACAM529 may then be purified with respect to host cell DNA and proteins by a novel purification scheme, which includes a combination of endonuclease treatment, depth filtration, anion-exchange chromatography and ultrafiltration/diafiltration (UF/DF). The resultant virus retains infectivity and is ∼ 200-fold more pure with respect to host cell DNA and proteins than is ACAM529 purified by ultracentrifugation. Additionally, we describe a side-by-side comparison of chromatography-purified ACAM529 with sucrose cushion-purified ACAM529, which shows that both preparations are equally immunogenic and protective when tested in vivo.


Assuntos
Herpes Genital/terapia , Herpesvirus Humano 2/imunologia , Vacinas Virais/uso terapêutico , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/biossíntese , Chlorocebus aethiops , Cromatografia por Troca Iônica , Sulfato de Dextrana/química , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Ultracentrifugação , Células Vero , Vacinas Virais/imunologia
15.
Ying Yong Sheng Tai Xue Bao ; 23(7): 1733-42, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23173443

RESUMO

Based on BIOME-BGC model and tree-ring data, a modeling study was conducted to estimate the dynamic changes of the net primary productivity (NPP) of Pinus tabulaeformis forest ecosystem in North China in 1952-2008, and explore the responses of the radial growth and NPP to regional climate warming as well as the dynamics of the NPP in the future climate change scenarios. The simulation results indicated the annual NPP of the P. tabulaeformis ecosystem in 1952-2008 fluctuated from 244.12 to 645.31 g C x m(-2) x a(-1), with a mean value of 418.6 g C x m(-2) x a(-1) The mean air temperature in May-June and the precipitation from previous August to current July were the main factors limiting the radial growth of P. tabulaeformis and the NPP of P. tabulaeformis ecosystem. In the study period, both the radial growth and the NPP presented a decreasing trend due to the regional warming and drying climate condition. In the future climate scenarios, the NPP would have positive responses to the increase of air temperature, precipitation, and their combination. The elevated CO2 would benefit the increase of the NPP, and the increment would be about 16.1% due to the CO2 fertilization. At both ecosystem and regional scales, the tree-ring data would be an ideal proxy to predict the ecosystem dynamic change, and could be used to validate and calibrate the process-based ecosystem models including BIOME-BGC.


Assuntos
Dióxido de Carbono/análise , Mudança Climática , Ecossistema , Pinus/fisiologia , Caules de Planta/anatomia & histologia , China , Simulação por Computador , Modelos Biológicos , Pinus/crescimento & desenvolvimento
16.
PLoS One ; 7(10): e46714, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071620

RESUMO

Herpes simplex virus type 2 (HSV-2) is a sexually transmitted virus that is highly prevalent worldwide, causing a range of symptoms that result in significant healthcare costs and human suffering. ACAM529 is a replication-defective vaccine candidate prepared by growing the previously described dl5-29 on a cell line appropriate for GMP manufacturing. This vaccine, when administered subcutaneously, was previously shown to protect mice from a lethal vaginal HSV-2 challenge and to afford better protection than adjuvanted glycoprotein D (gD) in guinea pigs. Here we show that ACAM529 given via the intramuscular route affords significantly greater immunogenicity and protection in comparison with subcutaneous administration in the mouse vaginal HSV-2 challenge model. Further, we describe a side-by-side comparison of intramuscular ACAM529 with a gD vaccine across a range of challenge virus doses. While differences in protection against death are not significant, ACAM529 protects significantly better against mucosal infection, reducing peak challenge virus shedding at the highest challenge dose by over 500-fold versus 5-fold for gD. Over 27% (11/40) of ACAM529-immunized animals were protected from viral shedding while 2.5% (1/40) were protected by the gD vaccine. Similarly, 35% (7/20) of mice vaccinated with ACAM529 were protected from infection of their dorsal root ganglia while none of the gD-vaccinated mice were protected. These results indicate that measuring infection of the vaginal mucosa and of dorsal root ganglia over a range of challenge doses is more sensitive than evaluating survival at a single challenge dose as a means of directly comparing vaccine efficacy in the mouse vaginal challenge model. The data also support further investigation of ACAM529 for prophylaxis in human subjects.


Assuntos
Herpes Genital/prevenção & controle , Vacinas contra o Vírus do Herpes Simples/administração & dosagem , Herpesvirus Humano 2/imunologia , Adjuvantes Imunológicos/administração & dosagem , Compostos de Alúmen/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Feminino , Gânglios Espinais/virologia , Herpes Genital/imunologia , Vacinas contra o Vírus do Herpes Simples/imunologia , Humanos , Injeções Intramusculares , Camundongos , Camundongos Endogâmicos BALB C , Oligodesoxirribonucleotídeos/administração & dosagem , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Vagina/virologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/imunologia
17.
Chem Biol Drug Des ; 78(6): 948-59, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21895985

RESUMO

In the current study, boosting regression has been proposed to model the activities of a series of phosphoramidate prodrugs of 2'-methylcytidine as inhibitors of hepatitis C virus. The stepwise multiple linear regression and particle swarm optimization strategies are used to select descriptors which are responsible for the inhibitory activity of these compounds. As comparisons to the boosting regression method, the multiple linear regression, back-propagation neural networks, and support vector machine have also been investigated. Experimental results have shown that the boosting can drastically enhance the generalization performance of individual multiple linear regression model and the particle swarm optimization-boosting method is a well-performing technique in quantitative structure-activity relationship studies superior to support vector machine. The squared correlation coefficient and standard deviation of the best model are 0.744 and 0.438 for the training set and 0.710 and 0.748 for the test set.


Assuntos
Amidas/química , Antivirais/química , Citidina/análogos & derivados , Citidina/química , Hepacivirus/efeitos dos fármacos , Ácidos Fosfóricos/química , Pró-Fármacos/química , Relação Quantitativa Estrutura-Atividade , Algoritmos , Antivirais/farmacologia , Citidina/farmacologia , Redes Neurais de Computação , Pró-Fármacos/farmacologia , Máquina de Vetores de Suporte
18.
Chin J Cancer ; 29(3): 288-93, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20193112

RESUMO

BACKGROUND AND OBJECTIVE: Invasion and metastasis are the most common causes of mortality for patients with colorectal neoplasms, and blocking invasion and metastasis in a timely fashion has become a hot research focus. We investigated the expression of the messenger RNA of Syndecan-1 and HPA-1 in colorectal cancer, and their correlation with invasion and metastasis. METHODS: Real-time fluorescent quantitative polymerase chain reaction (PCR) was used to detect the expression of Syndecan-1 and HPA-1 in specimens from 49 patients with colorectal cancer, 49 paired adjacent colorectal neoplasms (2 cm from the carcinoma), and 49 surgical margins of paired normal colorectal mucosa tissue (5 cm from the carcinoma), to analyze their correlation with clinicopathologic characteristics of colorectal neoplasm. RESULTS: The expression of HPA-1 mRNA was significantly higher in colorectal cancer (40.56 +/- 11.75) than that in the paired adjacent colorectal neoplasms (18.28 +/- 11.33) and normal colorectal mucosa tissue (10.80 +/- 10.20) (all P < 0.001). The expression of HPA-1 mRNA was significantly higher in paired adjacent colorectal neoplasms than that in normal colorectal mucosa (P < 0.05). The expression of Syndecan-1 mRNA was significantly higher in normal colorectal mucosa (61.21 +/- 12.96) than in the paired adjacent mucosa (14.35 +/- 11.06) or colorectal cancer (10.12 +/- 8.58) (all P < 0.001). The expression of Syndecan-1 mRNA was significantly higher in the paired adjacent mucosa than that in colorectal cancer (P < 0.05). The decreased expression of Syndecan-1 mRNA and the increased expression of HPA-1 were closely associated with the degree of differentiation, the depth of infiltration, lymph node metastasis, vessel metastasis, and TNM staging of colorectal cancer (all P < 0.05). Spearman rank correlation analysis demonstrated a significant correlation between Syndecan-1 and HPA-1(r = -0.405, P < 0.05). CONCLUSIONS: The expression of Syndecan-1 mRNA was significantly highest in normal colorectal mucosa and the expression of HPA-1 mRNA was significantly highest in colorectal cancer. At the same time, the decreased expression of Syndecan-1 mRNA and the increased expression of HPA-1 mRNA can promote the invasion and metastasis of colorectal cancer. The determination of Syndecan-1 and HPA-1 may be of value in the treatment as well as in the prognosis of patients with colorectal cancer.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Glucuronidase/metabolismo , Sindecana-1/metabolismo , Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Glucuronidase/genética , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Metástase Linfática , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sindecana-1/genética
19.
Virology ; 398(2): 243-50, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20060996

RESUMO

Old World monkey TRIM5alpha proteins are known to block the replication of human immunodeficiency virus and other retroviruses in a species-specific fashion. In this report, we show that specific forms of simian TRIM5alpha proteins can restrict herpes simplex virus (HSV) infection. To define the effect of TRIM5alpha on HSV replication, we examined HSV infection in HeLa cell lines that stably express simian and human orthologs of TRIM5alpha proteins. We demonstrated that several simian TRIM5alpha proteins can restrict HSV replication, with the TRIM5alpha protein of rhesus macaques showing the strongest inhibition of HSV infection. We also found that the level of the inhibition of virus replication was viral strain-specific. TRIM5alpha is likely to inhibit HSV at the early stage of infection; however, at later times of infection, the levels of TRIM5alpha are significantly decreased. Thus, some TRIM5alpha proteins exhibit antiviral effects that extend beyond retroviral infections, but HSV may be able to reduce this restriction by reducing TRIM5alpha levels during the later phases of virus replication. Our results also argue that TRIM5alpha is only part of the reduced level of HSV replication in rhesus macaques, which are known to be less susceptible to HSV infection than other primates.


Assuntos
Herpes Simples/virologia , Simplexvirus/fisiologia , Replicação Viral/fisiologia , Animais , Linhagem Celular , Fibroblastos/virologia , Regulação Viral da Expressão Gênica , Células HeLa/virologia , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 2/metabolismo , Humanos , Macaca mulatta/virologia , Fatores de Transcrição/fisiologia , Proteínas Virais/biossíntese
20.
Int J Mol Sci ; 10(8): 3316-3337, 2009 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-20111683

RESUMO

In the present work, the support vector machine (SVM) and Adaboost-SVM have been used to develop a classification model as a potential screening mechanism for a novel series of 5-HT(1A) selective ligands. Each compound is represented by calculated structural descriptors that encode topological features. The particle swarm optimization (PSO) and the stepwise multiple linear regression (Stepwise-MLR) methods have been used to search descriptor space and select the descriptors which are responsible for the inhibitory activity of these compounds. The model containing seven descriptors found by Adaboost-SVM, has showed better predictive capability than the other models. The total accuracy in prediction for the training and test set is 100.0% and 95.0% for PSO-Adaboost-SVM, 99.1% and 92.5% for PSO-SVM, 99.1% and 82.5% for Stepwise-MLR-Adaboost-SVM, 99.1% and 77.5% for Stepwise-MLR-SVM, respectively. The results indicate that Adaboost-SVM can be used as a useful modeling tool for QSAR studies.


Assuntos
Algoritmos , Ligantes , Receptor 5-HT1A de Serotonina/química , Cinética , Modelos Moleculares , Ligação Proteica , Relação Quantitativa Estrutura-Atividade , Receptor 5-HT1A de Serotonina/metabolismo , Máquina de Vetores de Suporte
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