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1.

Background

We conducted a Phase I randomized, dose-escalation, route-comparison trial of MVA-CMDR, a candidate HIV-1 vaccine based on a recombinant modified vaccinia Ankara viral vector expressing HIV-1 genes env/gag/pol. The HIV sequences were derived from circulating recombinant form CRF01_AE, which predominates in Thailand. The objective was to evaluate safety and immunogenicity of MVA-CMDR in human volunteers in the US and Thailand.

Methodology/Principal Findings

MVA-CMDR or placebo was administered intra-muscularly (IM; 107 or 108 pfu) or intradermally (ID; 106 or 107 pfu) at months 0, 1 and 3, to 48 healthy volunteers at low risk for HIV-1 infection. Twelve volunteers in each dosage group were randomized to receive MVA-CMDR or placebo (10∶2). Volunteers were actively monitored for local and systemic reactogenicity and adverse events post vaccination. Cellular immunogenicity was assessed by a validated IFNγ Elispot assay, an intracellular cytokine staining assay, lymphocyte proliferation and a 51Cr-release assay. Humoral immunogenicity was assessed by ADCC for gp120 and binding antibody ELISAs for gp120 and p24. MVA-CMDR was safe and well tolerated with no vaccine related serious adverse events. Cell-mediated immune responses were: (i) moderate in magnitude (median IFNγ Elispot of 78 SFC/106 PBMC at 108 pfu IM), but high in response rate (70% 51Cr-release positive; 90% Elispot positive; 100% ICS positive, at 108 pfu IM); (ii) predominantly HIV Env-specific CD4+ T cells, with a high proliferative capacity and durable for at least 6 months (100% LPA response rate by the IM route); (iv) dose- and route-dependent with 108 pfu IM being the most immunogenic treatment. Binding antibodies against gp120 and p24 were detectable in all vaccination groups with ADCC capacity detectable at the highest dose (40% positive at 108 pfu IM).

Conclusions/Significance

MVA-CMDR delivered both intramuscularly and intradermally was safe, well-tolerated and elicited durable cell-mediated and humoral immune responses.

Trial Registration

ClinicalTrials.gov NCT00376090  相似文献   

2.
Inactivation of Airborne Viruses by Ultraviolet Irradiation   总被引:6,自引:4,他引:2       下载免费PDF全文
Aerosolized viruses were passed through a high-intensity ultraviolet (UV) cell. This cell consisted of a long cylindrical aluminum tube [diameter, 7 in. (17.7 cm); length, 36 in. (91.4 cm)] with a highly reflective inner surface and a longitudinally extending helical baffle system which directed airborne particles in close proximity to a centrally located UV lamp. After having been passed through the UV cell, viral aerosols were collected with an Andersen sampler, and viral concentrations were determined by plaque assay methods on tissue cultures. Inactivation rates of greater than 99.9% were obtained for Coxsackie, influenza, Sindbis, and vaccinia viruses, and slightly less for adenovirus (96.8%), when the aerosols passed through the UV cell at 100 ft3/min. At aerosol flow rates of 200 ft3/min, inactivation rates were slightly lower; 91.3 for adenovirus, 97.5 and 96.7 for Coxsackie and Sindbis, respectively, and greater than 99.9% for influenza and vaccinia viruses.  相似文献   

3.

Rationale

During the recent H1N1 outbreak, obese patients had worsened lung injury and increased mortality. We used a murine model of influenza A pneumonia to test the hypothesis that leptin receptor deficiency might explain the enhanced mortality in obese patients.

Methods

We infected wild-type, obese mice globally deficient in the leptin receptor (db/db) and non-obese mice with tissue specific deletion of the leptin receptor in the lung epithelium (SPC-Cre/LepRfl/fl) or macrophages and alveolar type II cells (LysM-Cre/Leprfl/fl) with influenza A virus (A/WSN/33 [H1N1]) (500 and 1500 pfu/mouse) and measured mortality, viral clearance and several markers of lung injury severity.

Results

The clearance of influenza A virus from the lungs of mice was impaired in obese mice globally deficient in the leptin receptor (db/db) compared to normal weight wild-type mice. In contrast, non-obese, SP-C-Cre+/+/LepRfl/fl and LysM-Cre+/+/LepRfl/fl had improved viral clearance after influenza A infection. In obese mice, mortality was increased compared with wild-type mice, while the SP-C-Cre+/+/LepRfl/fl and LysM-Cre+/+/LepRfl /fl mice exhibited improved survival.

Conclusions

Global loss of the leptin receptor results in reduced viral clearance and worse outcomes following influenza A infection. These findings are not the result of the loss of leptin signaling in lung epithelial cells or macrophages. Our results suggest that factors associated with obesity or with leptin signaling in non-myeloid populations such as natural killer and T cells may be associated with worsened outcomes following influenza A infection.  相似文献   

4.

Introduction

Physical activity is known to significantly impact cardiometabolic health. Accelerometer data, as a measure of physical activity, can be used to objectively identify a disparity in movement (movement discordance) between healthy and unhealthy adults. The purpose of this study was to examine the Movement Discordance between healthy and unhealthy adults in a large US population sample.

Methods

Demographic, health and accelerometer data from the National Health and Nutrition Examination Study (NHANES) 2003–2004 and 2005–2006 cohorts were used for this study. Participants were classified as either having a “normal” or “abnormal” value for each cardiometabolic health parameter examined, based on published criteria. Linear regression analyses were performed to determine significance of each abnormal health parameter (risk factor) in its unique effect on the accelerometer counts, controlling for age and gender. Average accelerometer counts per minute (cpm) by gender and age categories were estimated separately for the groups of normal and abnormal cardiometabolic risk.

Results

Average cpm for those with healthy levels of each individual cardiometabolic health parameter range from 296 cpm (for C reactive protein) to 337 cpm (for waist circumference), while average cpm for those with abnormal levels of each individual cardiometabolic health parameter range from 216 cpm (for insulin) to 291 cpm (for LDL-cholesterol). After controlling for age and gender, waist circumference, HbA1c, Insulin, Homocysteine, and HDL-Cholesterol were the cardiometabolic health parameters that showed significant, unique and independent effects on cpm. Overall, individuals who have abnormal values for all significant cardiometabolic health parameters (“unhealthy”) averaged 267 cpm (SE = 15 cpm), while the healthy sample of this study averaged 428 cpm (SE = 10 cpm). The difference in cpm between the unhealthy and healthy groups is similar between males and females. Further, for both males and females, the cpm gap between unhealthy and healthy is largest in the 30s (males: 183 cpm; females 144 cpm) and lessens as age increases, with the lowest gap seen in those 80+ years (males, 81 cpm; females, 85 cpm).

Conclusion

This Movement Discordance between healthy and unhealthy adults represents a gap in movement that needs to be closed to improve the health of individuals with, or at risk for cardiometabolic disease.  相似文献   

5.
Summary We have previously demonstrated the ability of reovirus to function synergistically with chemotherapy in the treatment of murine EL-4 lymphoma. This study characterizes this treatment regimen in the therapy of L1210 leukemia. Animals with an estimated tumor burden of 107 cells were treated with 9 mg/kg 1,3-bis(2-chloroethyl)-1-nitrosourea. Reovirus type 3, which had been quantitated either by particles or plaque-forming units (pfu), was administered 48 h after chemotherapy. Complete remission of tumor was observed in 80% of the animals which received either 1011 particles or 109 pfu of reovirus. Cured animals were resistant to challenge with homologous tumor, but were susceptible to challenge with heterologous tumor. Reovirus undergoes limited replication at the tumor site, and virus-specific antibody appears only after disappearance of reovirus-infected cells and virus from the ascites fluid. Reovirus appears to function therapeutically by inducing a tumor-specific cytolytic immune response.  相似文献   

6.
The subcellular distributions of glutamyl carboxypeptidase, folate specific activities, and radioactive metabolites of injected [3H] folic acid were studied in rat liver. The specific activity of glutamyl carboxypeptidase in the lysosomal fraction was near or greater than four times that in the other subcellular fractions.The specific activity of folates was highest in the soluble fraction (102 ng folate/mg protein) and lowest in the microsomal fraction (22 ng folate/mg protein). Nuclear, mitochondrial, and lysosomal folates were 95% folate polyglutamates, and microsomal and soluble folates were 85–90% folate polyglutamates.Injected [3H] folic acid was initially concentrated in the microsomal fraction, as measured by 3H cpm per ng folate.Initially, injected [3H] folic acid was found converted to folate penta- and hexaglutamates in all fractions to a similar extent except in the microsomes where the percentage conversion was much less, as measured by the percentage of total 3H cpm determined to be [3H] folate penta- and hexaglutamates. At 24 h, the conversion of [3H] folates to penta- and hexaglutamates in each fraction was less than that found for the endogenous folates.Injected [3H] folic acid after 2 h was found to consist of 94% reduced folates in the soluble fraction, 56% in the mitochondrial, 55% in the nuclear, 20% in the lysosomal, and 15% in the microsomal fraction.  相似文献   

7.
The modification of virus particles has received a significant amount of attention for its tremendous potential for impacting gene therapy, oncolytic applications and vaccine development.1,2,3 Current approaches to modifying viral surfaces, which are mostly genetics-based, often suffer from attenuation of virus production, infectivity and cellular transduction.4,5 Using chemoselective click chemistry, we have developed a straightforward alternative approach which sidesteps these issues while remaining both highly flexible and accessible.1,2The goal of this protocol is to demonstrate the effectiveness of using bioorthogonal click chemistry to modify the surface of adenovirus type 5 particles. This two-step process can be used both therapeutically1 or analytically,2,6 as it allows for chemoselective ligation of targeting molecules, dyes or other molecules of interest onto proteins pre-labeled with azide tags. The three major advantages of this method are that (1) metabolic labeling demonstrates little to no impact on viral fitness,1,7 (2) a wide array of effector ligands can be utilized, and (3) it is remarkably fast, reliable and easy to access.1,2,7In the first step of this procedure, adenovirus particles are produced bearing either azidohomoalanine (Aha, a methionine surrogate) or the unnatural sugar O-linked N-azidoacetylglucosamine (O-GlcNAz), both of which contain the azide (-N3) functional group. After purification of the azide-modified virus particles, an alkyne probe containing the fluorescent TAMRA moiety is ligated in a chemoselective manner to the pre-labeled proteins or glycoproteins. Finally, an SDS-PAGE analysis is performed to demonstrate the successful ligation of the probe onto the viral capsid proteins. Aha incorporation is shown to label all viral capsid proteins (Hexon, Penton and Fiber), while O-GlcNAz incorporation results in labeling of Fiber only.In this evolving field, multiple methods for azide-alkyne ligation have been successfully developed; however only the two we have found to be most convenient are demonstrated herein – strain-promoted azide-alkyne cycloaddition (SPAAC) and copper-catalyzed azide-alkyne cycloaddition (CuAAC) under deoxygenated atmosphere.  相似文献   

8.

Background

Clock genes regulate circadian rhythm and are involved in various physiological processes, including digestion. We therefore investigated the association between the CLOCK 3111T/C single nucleotide polymorphism and the Period3 (PER3) variable-number tandem-repeat polymorphism (either 4 or 5 repeats 54 nt in length) with morning gastric motility.

Methods

Lifestyle questionnaires and anthropometric measurements were performed with 173 female volunteers (mean age, 19.4 years). Gastric motility, evaluated by electrogastrography (EGG), blood pressure, and heart rate levels were measured at 8:30 a.m. after an overnight fast. For gastric motility, the spectral powers (% normal power) and dominant frequency (DF, peak of the power spectrum) of the EGG were evaluated. The CLOCK and PER3 polymorphisms were determined by polymerase chain reaction (PCR) restriction fragment length polymorphism analysis.

Results

Subjects with the CLOCK C allele (T/C or C/C genotypes: n = 59) showed a significantly lower DF (mean, 2.56 cpm) than those with the T/T genotype (n = 114, 2.81 cpm, P < 0.05). Subjects with the longer PER3 allele (PER3 4/5 or PER3 5/5 genotypes: n = 65) also showed a significantly lower DF (2.55 cpm) than those with the shorter PER3 4/4 genotype (n = 108, 2.83 cpm, P < 0.05). Furthermore, subjects with both the T/C or C/C and PER3 4/5 or PER3 5/5 genotypes showed a significantly lower DF (2.43 cpm, P < 0.05) than subjects with other combinations of the alleles (T/T and PER3 4/4 genotype, T/C or C/C and PER3 4/4 genotypes, and T/T and PER3 4/5 or PER3 5/5 genotypes).

Conclusions

These results suggest that minor polymorphisms of the circadian rhythm genes CLOCK and PER3 may be associated with poor morning gastric motility, and may have a combinatorial effect. The present findings may offer a new viewpoint on the role of circadian rhythm genes on the peripheral circadian systems, including the time-keeping function of the gut.  相似文献   

9.
Human 293S cells, a cell line adapted to suspension culture, were grown to 5×106 cells/mL in batch with calcium-free DMEM. These cells, infected with new constructions of adenovirus vectors, yielded as much as 10 to 20% recombinant protein with respect to the total cellular protein content. Until recently, high specific productivity of recombinant protein was limited to low cell density infected cultures of no more than 5×105 cells/mL. In this paper, we show with a model protein, Protein Tyrosine Phosphatase 1C how high product yield can be maintained at high cell densities of 2×106 cells/mL by a medium replacement strategy. This allows the production of as much as 90 mg/L of active recombinant protein per culture volume. Analysis of key limiting/inhibiting medium components showed that glucose addition along with pH control can yield the same productivity as a medium replacement strategy at high cell density in calcium-free DMEM. Finally, the above results were reproduced in 3L bioreactor suspension culture thereby establishing the scalability of this expression system. The process we developed is used routinely with the same success for the production of various recombinant proteins and viruses.Abbreviations CFDMEM calcium-free DMEM - CS bovine calf serum - hpi hours post-infection - J+ enriched Joklik medium - MLP major late promoter - MOI multiplicity of infection (# of infectious viral particle/cell) - q specific consumption rate (mole/cell.h) - pfu plaque forming unit (# of infectious viral particle) - Y yield (g/E6 cells or mole/cell)  相似文献   

10.
Pathologic scar, characterized by excessive dermal fibrosis and scarring, is a common im-portant clinical sequela after wound healing. It often appears during wound healing after deep burn, surgical cutting and other injured skin. Accumulation of extracellular matrix (ECM) proteins is a manifestation of increased collagen synthesis and/or reduced matrix degradation, resulting in excessive scarring with a deformed appearance and dysfunction[1]. To date, treatment modalities to scar include sur…  相似文献   

11.
A complementary DNA (cDNA) encoding human hepatocyte growth factor was introduced into a replication-defective type 5 adenovirus (lacking E1, E3 domains) vector by homologous recombination of intracellular plasmid DNA, thus a recombinant vector containing HGF (Ad-HGF) was obtained. Ad-HGF and Ad-GFP (adenovirus vector carrying green fluorescence protein gene) were expanded in 293 cells and purified by cesium chloride gradient centrifugation for large-scale preparation, then were infected to the primarily cultured scar fibroblast of rabbit ear to observe the transfer efficiency and expression level of HGF in vitro. To evaluate the effect of Ad-HGF on established scar Ad-HGF solution was injected into excessively formed scar, which bears some clinical and histologic similarities to human hypertrophic scars. The results showed that: (i) the transfer efficiency was 36.8% ±14.1% on day 3 in primarily cultured scar fibroblasts treated with Ad-GFP and lasted more than 20 d; (ii) high-level expression of HGF protein was detected by means of ELISA in supernatant of scar fibroblasts treated with Ad-HGF, the amount of expression was 76 ng/4.0 x 105 cells on day 3; (iii) on day 32 after a single intradermal injection of Ad-HGF at different doses (8.6 x 109 pfu, 8.6 x 108 pfu, 8.6 x 107 pfu, 8.6 x 106 pfu) per scar, most of the scars in the former two dose groups were dramatically flattened, some were even similar to that of the normal skin. The value of Hl (hypertrophie index) showed that there was a therapeutic effect of Ad-HGF on scars at the dose of 109 pfu and 108 pfu. Whereas no therapeutic effects were seen at lower dose (107 pfu and 106 pfu of Ad-HGF) groups. In addition, clusters of hair were observed to different extent on healed wound treated with Ad-HGF. Histopathologic examination revealed that in most healed wounds of Ad-HGF treated group, the dermal layer was thinner, the amount of fibrous tissue was much fewer, and hair follicles growth and sebaceous glands were observed. In Sirius red-stained sections the amount of type I collagen in the Ad-HGF-treated scars was diminished markedly, compared to that in Ad-GFP group, in which a huge amount of type I collagen was still observed; (iv) immune response against HGF was absent. Antibody against HGF was not detectable by ELISA in serum from rabbit treated with Ad-HGF; (v) no local or systemic side-effects and toxicity associated with the gene transfer were found. These results demonstrated the potential use of treating pathologic scar by Ad-HGF, an alterative strategy of gene therapy for scar in clinical practice.  相似文献   

12.
Ferrets are widely used to study human influenza virus infection. Their airway physiology and cell receptor distribution makes them ideal for the analysis of pathogenesis and virus transmission, and for testing the efficacy of anti-influenza interventions and vaccines. The 2009 pandemic influenza virus (H1N1pdm09) induces mild to moderate respiratory disease in infected ferrets, following inoculation with 106 plaque-forming units (pfu) of virus. We have demonstrated that reducing the challenge dose to 102 pfu delays the onset of clinical signs by 1 day, and results in a modest reduction in clinical signs, and a less rapid nasal cavity innate immune response. There was also a delay in virus production in the upper respiratory tract, this was up to 9-fold greater and virus shedding was prolonged. Progression of infection to the lower respiratory tract was not noticeably delayed by the reduction in virus challenge. A dose of 104 pfu gave an infection that was intermediate between those of the 106 pfu and 102 pfu doses. To address the hypothesis that using a more authentic low challenge dose would facilitate a more sensitive model for antiviral efficacy, we used the well-known neuraminidase inhibitor, oseltamivir. Oseltamivir-treated and untreated ferrets were challenged with high (106 pfu) and low (102 pfu) doses of influenza H1N1pdm09 virus. The low dose treated ferrets showed significant delays in innate immune response and virus shedding, delayed onset of pathological changes in the nasal cavity, and reduced pathological changes and viral RNA load in the lung, relative to untreated ferrets. Importantly, these observations were not seen in treated animals when the high dose challenge was used. In summary, low dose challenge gives a disease that more closely parallels the disease parameters of human influenza infection, and provides an improved pre-clinical model for the assessment of influenza therapeutics, and potentially, influenza vaccines.  相似文献   

13.
Cellular proliferation and generation of cytotoxic lymphocytes in mixed lymphocyte culture reactions (MLC) results from cellular interactions initiated by individual differences in cell surface structures determined by the HLA-D locus. Cellular microtubular assemblies (MTA) modulate cell shape and surface architecture and have also been implicated in mediating stimulatory signals from the lymphocyte plasma membrane to intracellular sites. To assess the role of MTA in alloactivation, we tested the effect of colchicine, a microtubule-disrupting alkaloid, on the MLC. Diametrically opposite results were observed depending upon the colchicine treatment protocol. Brief exposure of stimulating cells to 10?6M colchicine resulted in an increase in [3H]thymidine incorporation from 30, 694 ± 2787 to 47,345 ± 4361 cpm/culture (mean ± SEM) (P < 0.001), exposure of responding cells to 10?6M colchicine resulted in an increase from 33,054 ± 4012 to 46,790 ± 5458 cpm/culture (P < 0.01), and exposure of both cells to 10?6M colchicine resulted in an increase from 33,054 ± 4012 to 52,685 ± 6720 cpm/culture (P < 0.01). However, direct addition of colchicine to a final concentration of 10?6M to MLCs at different times resulted in complete suppression of proliferation when added as late as 96 hr, and 63% suppression when added at 120 hr. Pretreatment of stimulating, responding, or both cells with lumicolchicine did not enhance proliferation. Pretreatment of cells with 10?6 and 10?4 M colchicine enhanced proliferation, while pretreatment with 10?2M colchicine prevented blastogenesis. The potentiation of proliferation induced by colchicine was evident as early as 48 hr after the initiation of the MLC. Generation of specific cytotoxic cells in the MLC was also enhanced by exposing lymphocytes to colchicine prior to the proliferative phase in six out of eight experiments (specific chromium release = 168% of control) despite constant effector:target ratios. These findings indicate that early disruption of microtubules leads to enhanced cellular proliferation and generation of cytotoxic lymphocytes in allogeneic one-way MLCs and suggest that the state of polymerization of the MTA may modulate immune responses involving cell-cell interactions.  相似文献   

14.
The structure of the complex between the Fab fragment of a human rhinovirus serotype 2 (HRV2) neutralizing antibody (8F5) and a cross-reactive synthetic peptide derived from the viral capsid protein VP2 has been recently determined by crystallographic methods.1 The conformation adopted by the peptide was very similar to and could be superimposed onto the corresponding region of the viral protein VP2 of human rhinovirus 1A (HRV1A) whose three-dimensional structure is known.2 The structure of the Fab fragment determined in the complex was docked onto the viral capsid using the superimposition transformation found for the peptide. In the resulting model the Fab protrudes almost radially to about 60 Å from the surface of the virion without any major steric problem. The Fab fragment was then placed on each one of the 60 equivalent epitopes using the T = 1 icosahedral symmetry of the virus. The closest pairs of Fab fragments are related by viral 2-fold axes and run almost parallel to each other without clashing. These axes of symmetry from the viral particle could thus be coincident with the dyad axes of the antibodies. Furthermore, comparison of the three-dimensional structure of the Fab/peptide complex with the structure of the Fab fragment alone3 indicates that the flexibility of the antibody's elbow would facilitate bivalent attachment to the same viral particle. In accordance with the docking results, experimental determination of the stoichiometry of binding yielded a ratio of 30 IgG molecules per virion also suggesting bivalent attachment of antibody 8F5 onto the viral particle. The neutralization of viral infectivity, being neither aggregation (this paper) nor inhibition of receptor binding,4 might be mainly achieved by reducing viral spread from cell to cell and/or inhibition of uncoating. © 1995 Wiley-Liss, Inc.  相似文献   

15.
《Life sciences》1995,56(20):PL383-PL388
To examine the role of the renin-angiotensin system on human vascular smooth muscle cell (VSMC) replication, we studied the effect of DUP753, an angiotensin II (ANG II) type 1 receptor antagonist, on ANG II stimulated tritiated-thymidine (3H-Tdr) incorporation into cultured human aortic VSMC. ANG II stimulated DNA synthesis of VSMC in a dose-dependent manner as estimated by 3H-Tdr incorporation (control; 2993 ± 486 cpm, 10−8M; 3360 ± 350 cpm, 10−7M; 3474 ± 516 cpm, 10−6M; 4889 ± 320 cpm, P < 0. 01). The effects of ANG II were clearly inhibited by 10−6M DUP 753 (ANG II 10−8M; 3360 ± 350 vs 509 ± 39 cpm, 10−7M; 3474 ± 516 vs 661 ± 36 cpm, 10−6M; 4889 ± 320 vs 806 ± 76 cpm, each P < 0. 01). This receptor antagonist decreased the basal 3H-Tdr incorporation of VSMC from 2933 ± 486 to 411 ±78 cpm (P < 0. 01). Furthermore, DUP 753 decreased 10−7M ANG II-stimulated 3H-Tdr incorporation of VSMC in a dose-dependent manner (control; 2627 ± 256 cpm, 10−9M; 2145 ± 143 cpm, 10−8M; 1047 ± 543 cpm, 10−7M; 639 ± 169 cpm, 10−6M; 642 ± 59 cpm, P < 0. 01). These observations suggest that, in human VSMC, ANG II type 1 receptors are important for the regulation of both stimulated and basal cell proliferation. It may therefore be worth while to examine the clinical usefulness of DUP 753 for preventing abnormal VSMC growth.  相似文献   

16.
Toluene-treated cells of Streptococcus diacetilactis produced large amounts of diacetyl and acetoin without 2,3-butylene glycol. With Na-[3-14C]pyruvate added to reaction mixtures in place of unlabeled pyruvate, diacetyl with specific activity of 6.1 × 104 cpm/μmol and acetoin with specific activity of 6.8 × 104 cpm/μmol were harvested. Growing cells of Enterobacter aerogens incubated 48 h at 30°C in a complex medium produced large amounts of 2,3-butylene glycol without acetoin or diacetyl. With uniformly labeled [14C]glucose added to the medium in place of unlabeled glucose, 2,3-butylene glycol with specific activity of 10.8 × 104 cpm/μmol was harvested. The radioactive chemicals were tested and found to be chromatographically homogeneous. Storage frozen in capped containers was especially important for diacetyl, which was found to evaporate rapidly from capped containers at room temperature.  相似文献   

17.

A novel and highly stable biomimetic oxidase sensor system was designed for catehol detection. FePP used as biomimetic horseradish peroxidase (HRP) was immobilized onto modified multi-walled carbon nanotubes (MWCNTs). Functional groups such as –OH, –NH2 and –COOH were introduced onto the surface of MWCNTs to provide biomimetic microenvironment for iron porphyrins (FePP). Stable biomimetic enzyme electrode has been developed to detect catechol as a simple, economical and efficient method. At optimal condition, the detection limit of OH-MWCNTs/FePP/Nafion was 3.754 × 10− 6 M. After stored at − 4 °C for 35 days, the oxidation current value still maintained 98.3% of initial activity. In repetitive nature test, relative standard deviation (RSD) of oxidation current remained within 1.0% after ten consecutive measurements in the same concentration of catechol solution, while most of reported oxidase sensor was within 2.0% under the same condition.

  相似文献   

18.
The effects of 2-deoxyglucose (DOG), an inhibitor of glycolysis, on guinea pig polymorphonuclear leukocytes (PMN) obtained from peritoneal exudates was examined. ATP levels in PMN were reduced by 40% by one hour following an incubation with 2-deoxyglucose. When complement (C3) coated 14C-staphylococcus aureus, C3 coated lipopolysaccharide-paraffin oil droplets (LPSPO), 14C-pneumococcus opsonized with IgG, or albumin coated paraffin oil droplets opsonized with IgG were added to cell suspensions containing DOG, the phagocytizing rate was 1,310 ± 55 cpm/5 x 106 cells/15 minutes, 6 ± 2 μg paraffin oil (PO)/107 cells/minute, 2,250 ± 175 cpm/1 x 106 cells/20 minutes or 0.037 ± 0.01 mg PO/107 cells/minute compared to control values of 5,970 ± 275 cpm/5 x 106 cells/15 minutes, 35 ± μg PO/107 cells/15 minutes, 4,510 ± 200 cpm/1 x 106 cells/20 minutes and 0.067 ± 0.01 mg PO/107 cells/minute. In parallel studies the phagocytic index for latex was 0.74 ± 0.28 in DOG compared to control of 2.36 ± 1.13 and the phagocytic rate of albumin coated paraffin oil droplets was 0.029 ± 0.01 mg PO/107 PMN/minute in DOG compared to control of 0.048 mg PO/107 cells/minute. When ATP levels were maintained by the simultaneous addition of 5 mM glucose or pyruvate to media containing DOG, latex ingestion was improved to 1.15 ± 0.3 with glucose and 1.59 ± 0.64 with pyruvate and albumin coated particles to 0.045 ± 0.01 mg PO/107 PMN/minute with pyruvate. There was no improvement in the uptake of either the C3 dependent particles or IgG coated Pneumococci in media containing DOG and glucose and/or pyruvate. Following the removal of DOG from the extracellular medium and the addition of pyruvate or glucose, phagocytosis of C3 dependent LPS-PO was restored to normal values. Neither the binding of C3 or IgG coated particles to the PMN nor the lateral movement of glycoprotein utilizing concanavalin A capping was affected by DOG. Thus, the presence of DOG in the PMN containing adequate amounts of ATP will selectively and reversibly inhibit those surface events required for phagocytosis of C3 and IgG bound particles but not latex particles or albumin particles which non-specifically bind to PMN.  相似文献   

19.
Summary Ryegrass was grown in sand containing35S-labelled sulphate adsorbed onto the surface of Al-hydrous oxide. S from this source was available to ryegrass even at very low surface coverage; and maximum yield of ryegrass occurred at an equilibrium solution concentration of 2 M S corresponding to about 10% coverage on the hydrous oxide.  相似文献   

20.

Rationale

HMG-CoA reductase inhibitors such as rosuvastatin may have immunomodulatory and anti-inflammatory effects that may reduce the severity of influenza A infection. We hypothesized that rosuvastatin would decrease viral replication, attenuate lung injury, and improve mortality following influenza A infection in mice.

Methods

C57Bl/6 mice were treated daily with rosuvastatin (10 mg/kg/day) supplemented in chow (or control chow) beginning three days prior to infection with either A//Udorn/72 [H3N2] or A/WSN/33 [H1N1] influenza A virus (1×105 pfu/mouse). Plaque assays were used to examine the effect of rosuvastatin on viral replication in vitro and in the lungs of infected mice. We measured cell count with differential, protein and cytokines in the bronchoalveolar lavage (BAL) fluid, histologic evidence of lung injury, and wet-to-dry ratio on Day 1, 2, 4, and 6. We also recorded daily weights and mortality.

Results

The administration of rosuvastatin had no effect on viral clearance of influenza A after infection. Weight loss, lung inflammation and lung injury severity were similar in the rosuvastatin and control treated mice. In the mice infected with influenza A (A/WSN/33), mortality was unaffected by treatment with rosuvastatin.

Conclusions

Statins did not alter the replication of influenza A in vitro or enhance its clearance from the lung in vivo. Statins neither attenuated the severity of influenza A-induced lung injury nor had an effect on influenza A-related mortality. Our data suggest that the association between HMG CoA reductase inhibitors and improved outcomes in patients with sepsis and pneumonia are not attributable to their effects on influenza A infection.  相似文献   

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