THE UTILIZATION OF ZWITTERIONIC BUFFER SYSTEM IN THE PLAQUE ASSAY OF A FELINE CALICIVIRUS

1973 ◽  
Vol 51 (2) ◽  
pp. 263-266 ◽  
Author(s):  
Daria N Love
Keyword(s):  
Plaque Assay ◽  
Feline Calicivirus ◽  
Buffer System ◽  
Zwitterionic Buffer

A carboxymethyl-cellulose plaque assay for feline calicivirus

2007 ◽  
Vol 146 (1-2) ◽  
pp. 393-396 ◽  
Author(s):  
Jaime Escobar-Herrera ◽  
Fernando José Medina-Ramírez ◽  
Ana Lorena Gutiérrez-Escolano
Keyword(s):  
Carboxymethyl Cellulose ◽  
Plaque Assay ◽  
Feline Calicivirus

A feline kidney cell line-based plaque assay for feline calicivirus, a surrogate for Norwalk virus

2003 ◽  
Vol 107 (2) ◽  
pp. 163-167 ◽  
Author(s):  
S Bidawid ◽  
N Malik ◽  
O Adegbunrin ◽  
S.A Sattar ◽  
J.M Farber
Keyword(s):  
Cell Line ◽  
Kidney Cell ◽  
Plaque Assay ◽  
Feline Calicivirus ◽  
Norwalk Virus ◽  
Kidney Cell Line

Comparative Efficacy of Seven Hand Sanitizers against Murine Norovirus, Feline Calicivirus, and GII.4 Norovirus†

2010 ◽  
Vol 73 (12) ◽  
pp. 2232-2238 ◽  
Author(s):  
GEUN WOO PARK ◽  
LESLIE BARCLAY ◽  
DAVID MACINGA ◽  
DUANE CHARBONNEAU ◽  
CHARLES A. PETTIGREW ◽  
...  
Keyword(s):  
Plaque Assay ◽  
Feline Calicivirus ◽  
Murine Norovirus ◽  
Comparative Efficacy ◽  
Pcr Assay ◽  
Reverse Transcription Pcr ◽  
Source Of Infection ◽  
Fecal Extract ◽  
Virucidal Efficacy

Contaminated hands or inanimate surfaces can act as a source of infection during outbreaks of human norovirus infection. We evaluated the virucidal efficacy of seven hand sanitizers containing various active ingredients, such as ethanol, triclosan, and chlorhexidine, and compared their effectiveness against feline calicivirus (FCV), murine norovirus (MNV), and a GII.4 norovirus fecal extract. We also tested the efficacy of 50, 70, and 90% of ethanol and isopropanol. Reduction of viral infectivity was measured by plaque assay, and the number of genomic copies was determined with a TaqMan real-time reverse transcription PCR assay. Based on the results of a quantitative suspension test, only one ethanol-based product (72% ethanol, pH 2.9) and one triclosan-based product (0.1% triclosan, pH 3.0) reduced the infectivity of both MNV and FCV (by >2.6 and ≥3.4 log units, respectively). Four of the seven products were effective against either MNV or FCV, whereas chlorhexidine was ineffective against both viruses. For these hand sanitizers, no correlation was found between reduced infectivity and decline of viral RNA. Ethanol and isopropanol concentrations ≥70% reduced the infectivity of MNV by ≥2.6 log units, whereas 50 and 70% ethanol reduced the infectivity of FCV by ≥2.2 log units after exposure for 5 min. The susceptibility of FCV to low pH and the relative high susceptibility of MNV to alcohols suggest that both surrogate viruses should be considered for in vitro testing of hand sanitizers.

Recovery and Disinfection of Two Human Norovirus Surrogates, Feline Calicivirus and Murine Norovirus, from Hard Nonporous and Soft Porous Surfaces

2015 ◽  
Vol 78 (10) ◽  
pp. 1842-1850 ◽  
Author(s):  
THOMAS YEARGIN ◽  
ANGELA FRASER ◽  
GUOHUI HUANG ◽  
XIUPING JIANG
Keyword(s):  
Sodium Hypochlorite ◽  
Limit Of Detection ◽  
Plaque Assay ◽  
Viral Rna ◽  
Feline Calicivirus ◽  
Murine Norovirus ◽  
Human Norovirus ◽  
Surface Type ◽  
Log Reduction ◽  
Porous Surfaces

Human norovirus is a leading cause of foodborne disease and can be transmitted through many routes, including environmental exposure to fomites. In this study, both the recovery and inactivation of two human norovirus surrogates, feline calicivirus (FCV) and murine norovirus (MNV), on hard nonporous surfaces (glass) and soft porous surfaces (polyester and cotton) were evaluated by both plaque assay and reverse transcription quantitative PCR method. Two disinfectants, sodium hypochlorite (8.25%) and accelerated hydrogen peroxide (AHP, at 4.25%) were evaluated for disinfection efficacy. Five coupons per surface type were used to evaluate the recovery of FCV and MNV by sonication and stomaching and the disinfection of each surface type by using 5 ml of disinfectant for a contact time of 5 min. FCV at an initial titer of ca. 7 log PFU/ml was recovered from glass, cotton, and polyester at 6.2, 5.4, and 3.8 log PFU/ml, respectively, compared with 5.5, 5.2, and 4.1 log PFU/ml, respectively, for MNV with an initial titer of ca. 6 log PFU/ml. The use of sodium hypochlorite (5,000 ppm) was able to inactivate both FCV and MNV (3.1 to 5.5 log PFU/ml) below the limit of detection on all three surface types. AHP (2,656 ppm) inactivated FCV (3.1 to 5.5 log PFU/ml) below the limit of detection for all three surface types but achieved minimal inactivation of MNV (0.17 to 1.37 log PFU/ml). Reduction of viral RNA by sodium hypochlorite corresponded to 2.72 to 4.06 log reduction for FCV and 2.07 to 3.04 log reduction for MNV on all three surface types. Reduction of viral RNA by AHP corresponded to 1.89 to 3.4 log reduction for FCV and 0.54 to 0.85 log reduction for MNV. Our results clearly indicate that both virus and surface types significantly influence recovery efficiency and disinfection efficacy. Based on the performance of our proposed testing method, an improvement in virus recovery will be needed to effectively validate virus disinfection of soft porous surfaces.

Tenacity of Human Norovirus and the Surrogates Feline Calicivirus and Murine Norovirus during Long-Term Storage on Common Nonporous Food Contact Surfaces

2015 ◽  
Vol 78 (1) ◽  
pp. 224-229 ◽  
Author(s):  
SASCHA MORMANN ◽  
CATHRIN HEIßENBERG ◽  
JENS PFANNEBECKER ◽  
BARBARA BECKER
Keyword(s):  
Stainless Steel ◽  
Real Time ◽  
Room Temperature ◽  
Plaque Assay ◽  
Feline Calicivirus ◽  
Murine Norovirus ◽  
Rt Pcr ◽  
Human Norovirus ◽  
Food Contact Surfaces ◽  
Contact Surfaces

The transfer of human norovirus (hNV) to food via contaminated surfaces is highly probable during food production, processing, and preparation. In this study, the tenacity of hNV and its cultivable surrogates feline calicivirus (FCV) and murine norovirus (MNV) on two common nonporous surface materials at two storage temperatures was directly compared. Virus titer reduction on artificially inoculated stainless steel and plastic carriers was monitored for 70 days at room temperature and at 7°C. Viruses were recovered at various time points by elution. Genomes from intact capsids (hNV, FCV, and MNV) were quantified with real-time reverse transcription (RT) PCR, and infectivity (FCV and MNV) was assessed with plaque assay. RNase treatment before RNA extraction was used to eliminate exposed RNA and to assess capsid integrity. No significant differences in titer reduction were found between materials (stainless steel or plastic) with the plaque assay or the real-time quantitative RT-PCR. At room temperature, infectious FCV and MNV were detected for 7 days. Titers of intact hNV, FCV, and MNV capsids dropped gradually and were still detectable after 70 days with a loss of 3 to 4 log units. At 7°C, the viruses were considerably more stable than they were at room temperature. Although only MNV infectivity was unchanged after 70 days, the numbers of intact capsids (hNV, FCV, and MNV) were stable with less than a 1-log reduction. The results indicate that hNV persists on food contact surfaces and seems to remain infective for weeks. MNV appears to be more stable than FCV at 7°C, and thus is the most suitable surrogate for hNV under dry conditions. Although a perfect quantitative correlation between intact capsids and infective particles was not obtained, real-time quantitative RT-PCR provided qualitative data about hNV inactivation characteristics. The results of this comparative study might support future efforts in assessment of foodborne virus risk and food safety.

scholarly journals Isolation and Molecular Charcteristic of a Recombinant Feline Calicivirus from Qingdao, China

2021 ◽  
Author(s):  
Yongxiang Liu ◽  
Xiaoliang Hu ◽  
Lide Qin
Keyword(s):  
Amino Acid ◽  
Recombinant Virus ◽  
Plaque Assay ◽  
Oral Disease ◽  
Feline Calicivirus ◽  
Recombination Analysis ◽  
Upper Respiratory Tract ◽  
Sequence Identity ◽  
Oropharyngeal Swab ◽  
Upper Respiratory

Abstract Feline calicivirus (FCV) is a highly contagious pathogen that can cause seriously upper respiratory tract and oral disease in feline. Despite widespread vaccination, the prevalence of FCV remains high. In this study, the FCV qd/2019/china was isolated from domestic feline oropharyngeal swab which was collected in qingdao, China. The virus was purified with plaque assay and identified with PCR and IFA method. the capsid amino acid ,VP1, of qd/2019/china [1] showed sequence identity with other isolate ranging from 83.9% (ym3/2001/jp) to 91.1% (CH-JL4) .Sequence analysis of the capsid amino acid revealed that qd/2019/china was closely related to CH-JL4 and clustered with CH-JL4 in the phylogenetic tree. Phylogenetic analysis indicated that complete genome of qd/2019/china and CH-JL4 was also classified into the same cluster. While the recombination analysis with Simplot indicate that the qd/2019/china originated from the recombination of CH-JL4 and HRB-SS, and the region 3821–5301 nt originated from HRB-SS. Further, the region 3821–5301 nt belong to protease -polymerase (PP) of HRB-SS. Here we isolate a new FCV qd/2019/china, which may be a recombinant virus, These results were beneficial for understanding the evolution of FCV.

Survival of Calicivirus in Foods and on Surfaces: Experiments with Feline Calicivirus as a Surrogate for Norovirus

2007 ◽  
Vol 70 (2) ◽  
pp. 500-503 ◽  
Author(s):  
K. MATTISON ◽  
K. KARTHIKEYAN ◽  
M. ABEBE ◽  
N. MALIK ◽  
S. A. SATTAR ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Food Processing ◽  
Infectious Virus ◽  
Large Body ◽  
Plaque Assay ◽  
Animal Origin ◽  
Feline Calicivirus ◽  
Fecal Suspension ◽  
Virus Survival ◽  
And Control

Although there is a large body of evidence incriminating foods as vehicles in the transmission of norovirus, little is known about virus survival in foods and on surfaces. Feline calicivirus was used as a surrogate for norovirus to investigate its survival in representative foods of plant and animal origin and on metal surfaces. Known concentrations of feline calicivirus in a natural fecal suspension were deposited onto lettuce, strawberries, ham, or stainless steel and incubated for 7 days at refrigeration or room temperatures. Virus was recovered at 1-day intervals, and the titers of the virus were determined by plaque assay. Infectious virus was recoverable until day 7 from lettuce, ham, and stainless steel. Statistically higher titers of feline calicivirus (P < 0.05) were recovered from ham under all conditions than from lettuce, strawberries, or stainless steel. These data provide valuable information for epidemiological and monitoring purposes as well as for the development of food processing practices and appropriate strategies to inactivate norovirus and control its transmission via foods and surfaces.

Fibrin Formation: The Role of the Fibrinogen-Fibrin Monomer Complex

1976 ◽  
Vol 36 (01) ◽  
pp. 037-048 ◽  
Author(s):  
Eric P. Brass ◽  
Walter B. Forman ◽  
Robert V. Edwards ◽  
Olgierd Lindan
Keyword(s):  
Particle Size ◽  
Induction Period ◽  
Fibrin Clot ◽  
Clot Formation ◽  
Appreciable Amount ◽  
Buffer System ◽  
Homeostatic Mechanism ◽  
Fibrin Formation ◽  
Fibrin Monomer

SummaryThe process of fibrin formation using highly purified fibrinogen and thrombin was studied using laser fluctuation spectroscopy, a method that rapidly determines particle size in a solution. Two periods in fibrin clot formation were noted: an induction period during which no fibrin polymerization occurred and a period of rapid increase in particle size. Direct measurement of fibrin monomer polymerization and fibrinopeptide release showed no evidence of an induction period. These observations were best explained by a kinetic model for fibrin clot formation incorporating a reversible fibrinogen-fibrin monomer complex. In this model, the complex serves as a buffer system during the earliest phase of fibrin formation. This prevents the accumulation of free polymerizable fibrin monomer until an appreciable amount of fibrinogen has reacted with thrombin, at which point the fibrin monomer level rises rapidly and polymerization proceeds. Clinically, the complex may be a homeostatic mechanism preventing pathological clotting during periods of elevated fibrinogen.

Human Blood Platelet Membrane Glycoproteins

1979 ◽  
Vol 42 (05) ◽  
pp. 1490-1502 ◽  
Author(s):  
C S P Jenkins ◽  
E F Ali-Briggs ◽  
G T E Zonneveld ◽  
A Sturk ◽  
J Clemetson
Keyword(s):  
Specific Problem ◽  
Sodium Dodecyl ◽  
Normal Subjects ◽  
Blood Platelet ◽  
Platelet Membrane ◽  
Buffer System ◽  
Membrane Glycoprotein ◽  
Membrane Glycoproteins ◽  
Human Blood Platelet ◽  
Electrophoretic Techniques

SummaryThe separation of the major platelet membrane glycoproteins of normal subjects and subjects with well defined platelet membrane glycoprotein abnormalities have been examined using four different polyacrylamide gel electrophoretic techniques (continuous and discontinuous). The mobilities of the resolved glycoprotein bands have been correlated with the glycoprotein nomenclature proposed for the conventional sodium dodecyl sulphate- phosphate buffer system. Since the glycoprotein distribution varies depending on the system used, the merits of each method should be considered before application to a specific problem.

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