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1.
Zhonghua Yi Xue Za Zhi ; 102(29): 2290-2294, 2022 Aug 09.
Article in Chinese | MEDLINE | ID: mdl-35927061

ABSTRACT

Objective: To investigate the effect of the degrees of myelosuppression on the curative effect and prognosis of triple-negative breast cancer with neoadjuvant chemotherapy. Methods: The clinical, pathological and follow-up data of 206 patients with triple negative breast cancer who received neoadjuvant chemotherapy with docetaxel combined with epirubicin combined with cyclophosphamide regimen in the Department of Breast Surgery in the Third Affiliated Hospital of Zhengzhou University from January 2013 to December 2018 were collected retrospectively. All were female, aged 28-71 (47.8±10.7) years. According to the WHO classification standard of acute and subacute toxicity of anticancer drugs, the patients were divided into 98 cases in the mild group (0-Ⅱ degree) and 108 cases in the severe group (Ⅲ-Ⅳ degree) according to the degree of bone marrow suppression after chemotherapy. The baseline clinicopathological features, pathological complete remission rate (PCR) and objective remission rate (ORR) of the two groups were compared. The survival curve was drawn by Kaplan Meier method, and the differences of disease-free survival (DFS), local recurrence free survival (LRFS), distant metastasis free survival (DMFS) and overall survival (OS) between the two groups were analyzed by log rank test. Cox regression risk model was used to analyze the related factors affecting the survival of the patients. Results: There were no significant differences in baseline clinicopathological characteristics of patients between the two groups, such as age, physical status score, menopausal status, body mass index, histological grade, clinical T stage, clinical N stage and Ki-67 index (all P>0.05). The severe group had higher PCR, longer median DFS and median DMFS than the mild group [50.9%(55/108) vs 36.7%(36/98); not reached vs 72 months; not reached vs 84 months] (all P<0.05). There was no significant difference in ORR, LRFS and OS between the two groups [89.8%(97/108) vs 81.6%(80/98); both not reached; both not reached] (all P>0.05). The degree of bone marrow suppression after neoadjuvant chemotherapy was an influential factor of DFS in TNBC patients (P=0.025). Compared with mild myelosuppression group, severe myelosuppression group had better disease-free survival prognosis (HR=0.571, 95%CI: 0.349-0.934). Conclusion: The prognosis of grade Ⅲ/Ⅳ myelosuppression is better than grade 0/Ⅰ/Ⅱ myelosuppression in patients with triple-negative breast cancer during neoadjuvant chemotherapy with TEC regimen, which is helpful for judging efficacy.


Subject(s)
Breast Neoplasms , Triple Negative Breast Neoplasms , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Disease-Free Survival , Epirubicin/therapeutic use , Female , Humans , Male , Neoadjuvant Therapy , Prognosis , Retrospective Studies , Treatment Outcome , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology
2.
Animal ; 15(3): 100146, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33573957

ABSTRACT

Ruminants can tolerate moderate concentrations of dietary tannin, making it feasible to replace corn with sorghum in ruminant diets; however, conditioning temperature of pelleted total mixed ration (PTMR) greatly affects nutrient digestibility. The objective was to determine effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs. This was a 2 × 3 factorial study, with corn and sorghum and three conditioning temperatures (65, 75 and 85 °C) in a randomized complete design, with 36 lambs (120 ±â€¯10.2 d and 24.9 ±â€¯3.3 kg) grouped by weight and randomly allocated. The resulting six PTMRs were referred to as 65-S, 75-S and 85-S for sorghum-based diets, and 65-C, 75-C and 85-C for corn-based diets, for low, medium and high pelleting temperatures, respectively. There was no grain type × conditioning temperature (Grain × Temp) interaction on growth performance and apparent nutrient digestibility. Furthermore, grain type did not affect DM intake (DMI), average daily gain (ADG) or feed conversion ratio (FCR) of fattening lambs. Pelleting at 75 °C improved ADG (P < 0.03) and FCR (P < 0.02) of fattening lambs compared to other temperatures. There was a Grain × Temp interaction (P < 0.01) on ruminal pH (lowest in lambs fed 75-S). There tended (P = 0.07) to be a Grain × Temp interaction for total volatile fatty acid (VFA), and there were Grain × Temp interactions for molar proportions of acetate (P < 0.04), butyrate (P < 0.03) and branch-chained VFA (P < 0.01). Lambs fed sorghum-based PTMR had greater molar proportion of propionate (P < 0.03) and lower acetate to propionate ratio (A:P, P < 0.04). Lambs fed sorghum-based PTMR had higher plasma concentrations of urea nitrogen (N) (P < 0.03), glucose (P < 0.01) and alkaline phosphatase (P < 0.05), whereas other blood metabolites were not affected by treatments. There were Grain × Temp (P < 0.03) interactions for color coordinates of longissimus and mid-gluteal muscle. Lambs fed sorghum-based PTMR had lower (P < 0.01) dressing percentage and meat quality than those fed corn-based PTMR. We concluded that sorghum can replace corn in lamb diets without compromising growth performance and feed efficiency; furthermore, feeding sorghum vs corn improved rumen fermentation, with reduced A:P ratio and enhanced N and glucose utilization. Finally, pelleting at 75 °C increased feeding value of either sorghum- or corn-based PTMR for fattening lambs.


Subject(s)
Animal Feed , Rumen , Animal Feed/analysis , Animals , Diet/veterinary , Digestion , Fermentation , Meat , Rumen/metabolism , Sheep , Temperature , Zea mays
3.
Opt Lett ; 45(22): 6186-6189, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-33186946

ABSTRACT

A parallel structured optical fiber Fabry-Perot interferometer sensor is proposed and demonstrated for refractive index and strain sensing with low temperature cross sensitivity. The device consists of two Fabry-Perot cavities fabricated by a femtosecond laser: one is inscribed in the fiber surface waveguide and used for sensing, and the other one is located in the fiber core for referencing. Part of the light propagating in the fiber core can be directed to the fiber surface waveguide via an X coupler. Because of the evanescent field, the light traveling along the fiber surface waveguide interacts with the surrounding medium and enables external refractive index sensing. The measurement sensitivity of the device is enhanced due to the Vernier effect associated with the parallel structured two Fabry-Perot interferometers. The sensitivities of ∼843.3nm/RIU and ∼101.8pm/µÎµ have been obtained for refractive index and strain, respectively, and the corresponding temperature cross sensitivities are ∼9.6×10-6RIU/∘C and ∼7.956×10-2µÎµ/∘C, respectively. The device is featured with high robustness, compact size, and large sensitivity.

4.
Eur Rev Med Pharmacol Sci ; 24(9): 4810-4821, 2020 05.
Article in English | MEDLINE | ID: mdl-32432744

ABSTRACT

OBJECTIVE: Recently, lncRNA has been determined to play an important role in cancer formation and development. However, the regulatory mechanism of lncRNA in NSCLC has not been fully explored. PATIENTS AND METHODS: The expression of NEAT1, miR-376b-3p, and SULF1 was detected in each group via quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The proteins expression of SULF1, p-MAPK, MAPK, p-Akt, Akt, and GAPDH were measured via Western blot. MTT assay was applied to detect cell proliferation in each group. Transwell assay was used to assess cell invasion and migration of each group. Cell apoptosis was assessed with flow cytometry. The relationship among NEAT1, miR-376b-3p, and SULF1 was determined using Luciferase reporter assay. RESULTS: In this study, the expression of NEAT1 and SULF1 was upregulated in NSCLC tissues and cells. Of note, the knockdown of NEAT1 and SULF1 could inhibit cell proliferation, migration, and invasion and promote cell apoptosis in NSCLC. Moreover, NEAT1 regulated SULF1 expression via binding to miR-376b-3p in NSCLC cells. Otherwise, the effects of NEAT1 on cell growth and apoptosis were reversed by improving the SULF1 expression in NSCLC cells. Meanwhile, si-NEAT1 transfection inhibited MAPK and Akt signaling pathway by modulating SULF1 in NSCLC cells. CONCLUSIONS: In this study, we found that lncRNA NEAT1 regulated cell proliferation, invasion, migration, and apoptosis by targeting has-miR-376b-3p/SULF1 axis in NSCLC. Moreover, the regulatory network of NEAT1 participated in the phosphorylation levels of MAPK and Akt to affect cell progression of NSCLC, providing a new regulatory pathway in the pathogenesis of lung cancer.


Subject(s)
Apoptosis , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Movement , Lung Neoplasms/metabolism , MicroRNAs/metabolism , RNA, Long Noncoding/metabolism , Sulfotransferases/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation , Humans , Lung Neoplasms/pathology , MicroRNAs/genetics , RNA, Long Noncoding/genetics , Sulfotransferases/genetics
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 45(11): 948-953, 2017 Nov 24.
Article in Chinese | MEDLINE | ID: mdl-29166721

ABSTRACT

Objective: To retrospectively analyze the potential correlation between cardiac magnetic resonance (CMR) imaging and clinical features and idiopathic arrhythmia in patients with straight back syndrome (SBS). Methods: Patients receiving CMR imaging examination from April 2015 to March 2016 at our department (n=1 432) were screened, 76 patients met the diagnosis criteria of flat chest (anteroposterior diameter/transthoracic diameter (APD/TTD) ratio<0.37 at the T8 vertebra). After excluding 33 patients with structural heart disease, 43 SBS patients were divided into two groups: SBS without obvious morphological change in the heart (group A, n=19) and SBS with morphological change of the heart (group B, n=24). CMR images were analyzed, focusing the heart morphological changes induced by SBS. The clinical data were collected to comprehensively analyze the medical history, electrocardiogram and electrophysiological examination in order to observe the relationship between SBS induced heart morphological change and the arrhythmia type and origin. Results: There were 21 male patients in this cohort, mean age was (28.5±11.5) years (13-58 years). APD/TTD ratio was similar between the two groups (0.30±0.03 vs. 0.29±0.04, P>0.05). LVEF tended to be lower in group B than in group A ((47.48±12.77)%vs. (59.31±9.04)%, P>0.05) . In group B, there were 15 patients with left ventricular enlargement, 2 with left ventricular wall thickening, 5 with uncoordinated ventricular wall motion, 5 with tricuspid regurgitation, 3 with mitral regurgitation, 2 with myocardial fibrosis, 5 with increased trabecular and 16 with decreased left ventricular function. Direct compression sign of right ventricle (disappeared precordial fat tissue space, secondary right atria enlargement and tricuspid regurgitation) and left atria (with or without secondary left ventricular enlargement and mitral regurgitation) were evidenced in patients of group B. CMR revealed that the arrhythmia origin corresponded the compression site of the heart in 8 cases (42.1%) in group A and 13 cases (54.2%) in group B, not corresponded to the compression site in 6 patients (31.6%) in group A and in 7 patients (29.2%) in group B, not attributable in 5 patients (26.3%) in group A and 4 patients (16.7%) in group B. The percent of arrhythmia origin corresponded the compression site of the heart tended to be higher in group B as compared to group A (P>0.05). Conclusion: SBS can induce changes of cardiac morphology and cardiac function. SBS induced cardiac compression is linked with the development of arrhythmias and might be one of the reasons of arrhythmias in these patients.


Subject(s)
Arrhythmias, Cardiac/diagnostic imaging , Magnetic Resonance Imaging , Adolescent , Adult , Cardiomyopathies , Electrocardiography , Female , Heart Atria , Heart Ventricles , Humans , Male , Mitral Valve Insufficiency , Retrospective Studies , Tricuspid Valve Insufficiency , Ventricular Function, Left , Young Adult
6.
Genet Mol Res ; 15(4)2016 Oct 17.
Article in English | MEDLINE | ID: mdl-27813562

ABSTRACT

Chlorophyll (CHL) is present in many plant organs, and its metabolism is strongly regulated throughout plant development. Understanding the fate of CHL in senescent leaves or during fruit ripening is a complex process. The stay-green (SGR) protein has been shown to affect CHL degradation. In this study, we used the conserved sequences of STAY-GREEN domain protein (NP_567673) in Arabidopsis thaliana as a probe to search SGR family genes in the genome-wide melon protein database. Four candidate SGR family genes were identified in melon (Cucumis melo L. Hetao). The phylogenetic evolution, gene structure, and conserved motifs were subsequently analyzed. In order to verify the function of CmSGR genes in CHL degradation, CmSGR1 and CmSGR2 were transiently overexpressed and silenced using different plasmids in melon. Overexpression of CmSGR1 or CmSGR2 induced leaf yellowing or fruit ripening, while silencing of CmSGR1 or CmSGR2 via RNA interference delayed CHL breakdown during fruit ripening or leaf senescence compared with the wild type. Next, the expression profile was analyzed, and we found that CmSGR genes were expressed ubiquitously. Moreover, CmSGR1 and CmSGR2 were upregulated, and promoted fruit ripening. CmSGR3 and CmSGR4 were more highly expressed in leaves, cotyledon, and stem compared with CmSGR1 or CmSGR2. Thus, we conclude that CmSGR genes are crucial for fruit ripening and leaf senescence. CmSGR protein structure and function were further clarified to provide a theoretical foundation and valuable information for improved performance of melon.


Subject(s)
Cucumis melo/genetics , Genes, Plant , Multigene Family , Agrobacterium/metabolism , Amino Acid Motifs , Amino Acid Sequence , Amino Acids/metabolism , Conserved Sequence , Exons/genetics , Fruit/genetics , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Introns/genetics , Phylogeny , Plant Proteins/chemistry , Plant Proteins/genetics , Plant Proteins/metabolism , Recombination, Genetic/genetics , Sequence Alignment , Species Specificity
7.
Food Microbiol ; 51: 69-73, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26187829

ABSTRACT

Efficacy of four bacteriophages (phages) and a cocktail for biocontrol of Escherichia coli O157 was assessed on beef samples stored at 4, 22 and 37 °C. Samples (3 × 3 × 1 cm) were contaminated with E. coli O157 (10(4) CFU/cm(2)) and treated with single phages: T5-like (T5), T1-like (T1), T4-like (T4) and O1-like (O1), or a cocktail at two titers: multiplicity of infection (MOI) = 1000 and MOI = 10. In contrast to previous studies, use of virucidal solution prevented over-estimation of phage efficacy. Irrespective of temperature and MOIs, T5 was most (P < 0.001) and O1 least (P < 0.05) effective for biocontrol of E. coli O157, with relative efficacy of other phages temperature dependent. At 4 °C, T1 (P < 0.05) and cocktail (P < 0.001) were more effective than T4. In contrast, T4 was equally (P = 0.08, at 37 °C) or less effective (P = 0.003, at 22 °C) than T5. Phages were more effective (P < 0.001) against E. coli O157 at warmer temperatures and high MOI. As the beef supply chain includes hours of storage or transport at temperatures near 4 °C, this study demonstrates phages could significantly reduce E. coli O157 during this period.


Subject(s)
Coliphages/physiology , Escherichia coli O157/physiology , Red Meat/microbiology , Red Meat/virology , Temperature , Animals , Bacteriophage T4/physiology , Biological Control Agents , Cattle , Escherichia coli Infections/prevention & control , Escherichia coli O157/growth & development , Food Microbiology , Microbial Viability
8.
Genet Mol Res ; 13(3): 5350-60, 2014 Jul 24.
Article in English | MEDLINE | ID: mdl-25078591

ABSTRACT

In order to obtain a salt-tolerant perennial alfalfa (Medicago sativa L.), we transferred the halophyte Salicornia europaea L. Na(+)/H(+) antiporter gene, SeNHX1, to alfalfa by using the Agrobacterium-mediated transformation method. The transformants were confirmed by both PCR and RT-PCR analyses. Of 197 plants that were obtained after transformation, 36 were positive by PCR analysis using 2 primer pairs for the CaMV35S-SeNHX1 and SeNHX1-Nos fragments; 6 plants survived in a greenhouse. RT-PCR analysis revealed that SeNHX1 was expressed in 5 plants. The resultant transgenic alfalfa had better salt tolerance. After stress treatment for 21 days with 0.6% NaCl, the chlorophyll and MDA contents in transgenic plants were lower, but proline content and SOD, POD, and CAT activities were higher than those in wild-type plants. These results suggest that the salt tolerance of transgenic alfalfa was improved by the overexpression of the SeNHX1 gene.


Subject(s)
Amaranthaceae/genetics , Gene Expression Regulation, Plant , Medicago sativa/genetics , Plant Proteins/genetics , Salt-Tolerant Plants/genetics , Sodium-Hydrogen Exchangers/genetics , Agrobacterium tumefaciens/genetics , Amaranthaceae/chemistry , Catalase/genetics , Catalase/metabolism , Chlorophyll/biosynthesis , Gene Transfer Techniques , Malondialdehyde/metabolism , Medicago sativa/drug effects , Medicago sativa/metabolism , Peroxidase/genetics , Peroxidase/metabolism , Plant Proteins/metabolism , Plants, Genetically Modified , Salt Tolerance , Salt-Tolerant Plants/drug effects , Salt-Tolerant Plants/metabolism , Sodium Chloride/pharmacology , Sodium-Hydrogen Exchangers/metabolism , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Transgenes
9.
Appl Environ Microbiol ; 80(13): 3819-25, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24747892

ABSTRACT

The objectives of this study were to identify endemic bacteriophages (phages) in the feedlot environment and determine relationships of these phages to Escherichia coli O157:H7 from cattle shedding high and low numbers of naturally occurring E. coli O157:H7. Angus crossbred steers were purchased from a southern Alberta (Canada) feedlot where cattle excreting ≥ 10(4) CFU · g(-1) of E. coli O157:H7 in feces at a single time point were identified as supershedders (SS; n = 6), and cattle excreting <10(4) CFU · g(-1) of feces were identified as low shedders (LS; n = 5). Fecal pats or fecal grabs were collected daily from individual cattle for 5 weeks. E. coli O157:H7 in feces was detected by immunomagnetic separation and enumerated by direct plating, and phages were isolated using short- and overnight-enrichment methods. The total prevalence of E. coli O157:H7 isolated from feces was 14.4% and did not differ between LS and SS (P = 0.972). The total prevalence of phages was higher in the LS group (20.9%) than in the SS group (8.3%; P = 0.01). Based on genome size estimated by pulsed-field gel electrophoresis and morphology determined by transmission electron microscopy, T4- and O1-like phages of Myoviridae and T1-like phage of Siphoviridae were isolated. Compared to T1- and O1-like phages, T4-like phages exhibited a broad host range and strong lytic capability when targeting E. coli O157:H7. Moreover, the T4-like phages were more frequently isolated from feces of LS than SS, suggesting that endemic phages may impact the shedding dynamics of E. coli O157:H7 in cattle.


Subject(s)
Bacterial Load , Bacterial Shedding , Coliphages/classification , Coliphages/isolation & purification , Escherichia coli Infections/veterinary , Escherichia coli O157/virology , Feces/microbiology , Alberta , Animals , Cattle , Coliphages/ultrastructure , DNA, Viral/genetics , Electrophoresis, Gel, Pulsed-Field , Escherichia coli Infections/microbiology , Escherichia coli O157/isolation & purification , Microscopy, Electron, Transmission , Myoviridae/classification , Myoviridae/isolation & purification , Myoviridae/ultrastructure , Siphoviridae/classification , Siphoviridae/isolation & purification , Siphoviridae/ultrastructure , Virion/ultrastructure
10.
J Appl Microbiol ; 114(6): 1592-603, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23489937

ABSTRACT

AIMS: This study aimed to characterize the impact of lytic and temperate bacteriophages on the genetic and phenotypic diversity of Mannheimia haemolytica from feedlot cattle. METHODS AND RESULTS: Strictly lytic phages were not detected from bovine nasopharyngeal (n = 689) or water trough (n = 30) samples, but Myoviridae- or Siphoviridae-like phages were induced from 54 of 72 M. haemolytica strains by mitomycin C, occasionally from the same strain. Phages with similar restriction fragment length polymorphism profiles (RFLP ≥70% relatedness) shared common host serotypes 1 or 2 (P < 0·0001). Likewise, phages with similar RFLP tended to occur in genetically related host bacteria (70-79% similarity). Host range assays showed that seven phages from host serotypes 1, 2 and 6 lysed representative strains of serotypes 1, 2 or 8. The genome of vB_MhM_1152AP from serotype 6 was found to be collinear with P2-like phage φMhaA1-PHL101. CONCLUSIONS: Prophages are a significant component of the genome of M. haemolytica and contribute significantly to host diversity. Further characterization of the role of prophage in virulence and persistence of M. haemolytica in cattle could provide insight into approaches to control this potential respiratory pathogen. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated that prophages are widespread within the genome of M. haemolytica isolates and emphasized the challenge of isolating lytic phage as a therapeutic against this pathogen.


Subject(s)
Bacteriophages/isolation & purification , Host Specificity , Mannheimia haemolytica/virology , Animals , Bacteriophages/classification , Bacteriophages/genetics , Cattle , Enrofloxacin , Fluoroquinolones/pharmacology , Genetic Variation , Mannheimia haemolytica/classification , Mannheimia haemolytica/genetics , Prophages/isolation & purification
11.
J Food Prot ; 73(7): 1304-12, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20615343

ABSTRACT

Bacteriophages are natural predators of bacteria and may mitigate Escherichia coli O157:H7 in cattle and their environment. As bacteriophages targeted to E. coli O157:H7 (phages) lose activity at low pH, protection from gastric acidity may enhance efficacy of orally administered phages. Polymer encapsulation of four phages, wV8, rV5, wV7, and wV11, and exposure to pH 3.0 for 20 min resulted in an average 13.6% recovery of phages after release from encapsulation at pH 7.2. In contrast, untreated phages under similar conditions had a complete loss of activity. Steers (n = 24) received 10(11) CFU of naladixic acid-resistant E. coli O157:H7 on day 0 and were housed in six pens of four steers. Two pens were control (naladixic acid-resistant E. coli O157:H7 only), and the remaining pens received polymer-encapsulated phages (Ephage) on days -1, 1, 3, 6, and 8. Two pens received Ephage orally in gelatin capsules (bolus; 10(10) PFU per steer per day), and the remaining two pens received Ephage top-dressed on their feed (feed; estimated 10(11) PFU per steer per day). Shedding of E. coli O157:H7 was monitored for 10 weeks by collecting fecal grab and hide swab samples. Acceptable activity of mixed phages at delivery to steers was found for bolus and feed, averaging 1.82 and 1.13 x 10(9) PFU/g, respectively. However, Ephage did not reduce shedding of naladixic acid-resistant E. coli O157:H7, although duration of shedding was reduced by 14 days (P < 0.1) in bolus-fed steers as compared with control steers. Two successful systems for delivery of Ephage were developed, but a better understanding of phage-E. coli O157:H7 ecology is required to make phage therapy a viable strategy for mitigation of this organism in feedlot cattle.


Subject(s)
Bacteriophages/physiology , Cattle Diseases/prevention & control , Escherichia coli Infections/veterinary , Escherichia coli O157/growth & development , Animal Feed/microbiology , Animal Nutritional Physiological Phenomena , Animals , Cattle , Cattle Diseases/microbiology , Cattle Diseases/transmission , Colony Count, Microbial , Consumer Product Safety , Escherichia coli Infections/microbiology , Escherichia coli Infections/prevention & control , Escherichia coli Infections/transmission , Food Contamination/prevention & control , Humans , Hydrogen-Ion Concentration , Male , Random Allocation
12.
J Appl Microbiol ; 107(2): 646-56, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19302306

ABSTRACT

AIMS: To evaluate host range and lytic capability of four bacteriophages (rV5, wV7, wV8 and wV11) against Escherichia coli O157:H7 (STEC O157:H7) from cattle and humans. METHODS AND RESULTS: Four hundred and twenty-two STEC O157:H7 isolates (297 bovine; 125 human) were obtained in Alberta, Canada. The four phages were serially diluted and incubated for 5 h with overnight cultures of STEC O157:H7 to estimate their multiplicity of infection (MOI). All bovine STEC O157:H7 were subjected to pulsed-field gel electrophoresis (PFGE) and phage typing (PT). Phage wV7 lysed all human and bovine isolates irrespective of PFGE genotype or PT phenotype and exhibited the lowest MOI (0.004-0.006, P < 0.0001) of all phages. Phages rV5 and wV11 exhibited a lower MOI (0.002-0.04, P < 0.0001) than did phage wV8 (25-29) and they had a narrower host range than wV7 or wV8. Phages rV5, wV11 and wV8 lysed 342 (81.0%), 321 (76.1%) and 407 (96.4%), respectively, of the 422 isolates. Susceptibility of bovine STEC O157:H7 to rV5, w11 and wV8 was influenced by PFGE genotype and/or PT phenotype. CONCLUSIONS: Phages exhibited activity against the majority of bovine and human STEC O157:H7 isolates. PFGE genotype and/or PT phenotype of the host-target influenced their vulnerability to phage attack. Susceptibility of bovine STEC O157:H7 to phage may also differ among farms. Both lytic capability and host range should be considered in the selection of therapeutic phage for on-farm control of STEC O157:H7. SIGNIFICANCE AND IMPACT OF THE STUDY: The present work indicates that a four-phage cocktail should be equally effective at mitigating STEC O157:H7 isolates both of bovine and of human origin. Given that some STEC O157:H7 exhibited resistance to some but not all phages, a phage cocktail is the logical approach to efficacious on-farm therapy.


Subject(s)
Bacteriolysis , Bacteriophages/growth & development , Escherichia coli O157/genetics , Escherichia coli O157/virology , Animals , Bacteriological Techniques , Bacteriophage Typing , Bacteriophages/genetics , Bacteriophages/isolation & purification , Canada , Cattle , Electrophoresis, Gel, Pulsed-Field , Escherichia coli O157/isolation & purification , Genotype , Humans , Phenotype
13.
Appl Environ Microbiol ; 75(5): 1271-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19139243

ABSTRACT

The relationship between endemic bacteriophages infecting E. coli O157:H7 (referred to as "phage") and levels of shedding of E. coli O157:H7 by cattle was investigated in two commercial feedlots in southern Alberta, Canada. Between May and November 2007, 10 pens of cattle were monitored by collection of pooled fecal pats, water with sediment from troughs, manure slurry from the pen floor, and rectal fecal samples from individual animals (20 per pen) at two separate times. Bacteriophages infecting E. coli O157:H7 were detected more frequently (P<0.001) after 18 to 20 h enrichment than by initial screening and were recovered in 239 of 855 samples (26.5% of 411 pooled fecal pats, 23.8% of 320 fecal grab samples, 21.8% of 87 water trough samples, and 94.6% of 37 pen floor slurry samples). Overall, prevalence of phage was highest (P<0.001) in slurry. Recovery of phage from pooled fecal pats was highest (P<0.05) in May. Overall recovery did not differ (P>0.10) between fecal grab samples and pooled fecal pats. A higher prevalence of phage in fecal pats or water trough samples was associated (P<0.01) with reduced prevalence of E. coli O157:H7 in rectal fecal samples. There was a weak but significant negative correlation between isolation of phage and E. coli O157:H7 in fecal grab samples (r= -0.11; P<0.05). These data demonstrate that the prevalence of phage fluctuates in a manner similar to that described for E. coli O157:H7. Phage were more prevalent in manure slurry than other environmental sources. The likelihood of fecal shedding of E. coli O157:H7 was reduced if cattle in the pen harbored phage.


Subject(s)
Coliphages/isolation & purification , Escherichia coli O157/isolation & purification , Feces/microbiology , Feces/virology , Sewage/microbiology , Sewage/virology , Alberta , Animals , Cattle , Colony Count, Microbial , Escherichia coli O157/virology , Seasons
14.
J Food Prot ; 71(4): 691-8, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18468021

ABSTRACT

This study was conducted to compare fecal grab (FEC) and rectoanal mucosal swab (RAMS) techniques as sampling methods for surveillance of Escherichia coli O157:H7 in conjunction with administration of a mitigation therapy. The study was nested within a larger experiment that investigated bacteriophage as a preharvest strategy for controlling E. coli O157:H7 in feedlot steers. Samples (FEC and RAMS) were collected from 16 of the 32 feedlot steers (control and oral bacteriophage treatment; n = 8) involved in the mitigation study. All steers had been inoculated on day 0 with 10(10) CFU of nalidixic acid-resistant E. coli O157:H7, and samples were collected on 16 occasions over the next 83 days. FEC samples were assessed by direct plating of serial dilutions in PBS, plus a 6-h enrichment and immunomagnetic separation when E. coli O157:H7 concentrations were below limits detectable by direct plating (i.e., <1 log CFU/g). All RAMS samples were assessed by enrichment and immunomagnetic separation. E. coli O157:H7 was detected more frequently (P < 0.01) by FEC than by RAMS. Overall, 213 of 256 samples were positive either by FEC or RAMS. Discrepancies between sampling techniques were observed in 63 of the 213 positive samples; FEC missed 11 samples that were positive by RAMS, and RAMS missed 52 of those positive by FEC (miss rates of 5.16 and 24.41%, respectively). Kappa values (0.36 to 0.45) indicated only fair to moderate agreement between FEC and RAMS results, but this agreement was higher at lower levels of E. coli O157:H7 shedding (later in the experimental period). Selection of sampling procedure could significantly influence the assessed merit during testing of potential strategies for controlling E. coli O157:H7 on the farm.


Subject(s)
Consumer Product Safety , Escherichia coli O157/isolation & purification , Feces/microbiology , Food Contamination/prevention & control , Intestinal Mucosa/microbiology , Anal Canal/microbiology , Animals , Bacteriophages/physiology , Cattle , Colony Count, Microbial , Food Contamination/analysis , Humans , Male , Meat/microbiology , Random Allocation , Rectum/microbiology , Sensitivity and Specificity
15.
Biochem Biophys Res Commun ; 337(1): 355-62, 2005 Nov 11.
Article in English | MEDLINE | ID: mdl-16185662

ABSTRACT

Fascin, an actin-bundling protein, induces membrane protrusions and increases cell motility in various transformed cells. The overexpression of fascin in esophageal squamous cell carcinoma (ESCC) has been described only recently, but the roles and mechanism still remained unclear. Here, by using RNA interference (RNAi), we have stably silenced the expression of the fascin in EC109 cells, an ESCC cell line. Down-regulation of fascin resulted in a suppression of cell proliferation and as well as a decrease in cell invasiveness. Furthermore, we revealed that fascin might have functions in regulating tumor growth in vivo. The effect of fascin on cell invasiveness correlated with the activation of matrix metalloproteases such as MMP-2 and MMP-9. We examined that fascin down-expression also led to a decrease of c-erbB-2 and beta-catenin at the protein level. These results suggested that fascin might play crucial roles in regulating neoplasm progression of ESCC.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Carrier Proteins/physiology , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/pathology , Microfilament Proteins/physiology , Animals , Carrier Proteins/antagonists & inhibitors , Carrier Proteins/genetics , Cell Line, Tumor , Cell Proliferation , Cytoskeletal Proteins/metabolism , Down-Regulation , HeLa Cells , Humans , Mice , Mice, Nude , Microfilament Proteins/antagonists & inhibitors , Microfilament Proteins/genetics , Neoplasm Invasiveness , RNA Interference , Receptor, ErbB-2/metabolism , Trans-Activators/metabolism , beta Catenin
16.
Sheng Wu Gong Cheng Xue Bao ; 17(3): 318-21, 2001 May.
Article in Chinese | MEDLINE | ID: mdl-11517609

ABSTRACT

The pUC19-OMT plasmids were cut by Ssp 1 and the products in 900 bp were recovered from low-melting agarose gel and used as probes which were labeled by Digoxigenin. After being denatured, the probes were dropped on the chromosome samples which were also denatured to anneal with them. The anti-digoxigenin antibodies labeled with colloidal gold were used to act with the chromosome samples. In order to localize the exogenous pGH genes(porcine growth hormone gene) on chromosomes detected with optical microscope and improve the sensitivity, digoxigen gold signals are amplified by silver precipitation. After calculating the number of silver grains on every chromosome under the optical microscope, we analyzed the data with statistical methods. The results show that the integrating sites of exogenous pGH genes are very different among the positives. However, it is clear that the exogenous genes in one are always of the tendency to integrate in one specific site on a certain chromosome. These data are of great significance for studying the site-specific integration and the expression efficiency of exogenous genes in the future research.


Subject(s)
Chromosome Mapping , Growth Hormone/genetics , Animals , Animals, Genetically Modified , Swine
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