Search

Simple Summary: Feline calicivirus (FCV) is a major cause of upper respiratory tract (URT) disease in cats that can lead to acute or subacute illness. It is highly contagious and widespread in the feline population, with many cats being asymptomatic carriers. However, FCV infection can also cause various clinical problems, resulting in high morbidity rates. Unfortunately, existing diagnostic techniques are not always sufficiently quick or specific enough to detect the virus, making it difficult to diagnose and treat. The current study compared the diagnostic abilities of different methods—polymerase chain reaction (PCR), nested PCR, and reverse transcription loop-mediated isothermal amplification (RT-LAMP)—to detect FCV in clinical samples from cats. The development of rapid and sensitive diagnostic methods is crucial for timely healing, reducing the risk of severe symptoms, and preventing the spread of viruses. Feline calicivirus (FCV) is a highly contagious virus that causes upper respiratory tract disease, commonly known as cat flu. It is widely distributed worldwide and poses a major threat to feline health. Therefore, it is essential to find an efficient and rapid method for detecting FCV. In this study, the colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay, using neutral red as an indicator, was developed and validated to target the ORF2 gene of FCV for the first time. Additionally, the study compared the diagnostic abilities of polymerase chain reaction (PCR), nested PCR, and RT-LAMP assays for detecting FCV in clinical samples. The optimized RT-LAMP amplification was carried out at 56.3 °C. The technique visually detected FCV within 70 min, with a limit of detection of 14.3 × 101 copies/µL, and showed no cross-reactivity with other feline pathogens. Out of 54 oropharyngeal swab samples, 17 tested positive for FCV using both nested PCR and RT-LAMP, while only one tested positive using conventional PCR. The positivity rate was higher with nested PCR and RT-LAMP (31.48%) compared to conventional PCR (1.85%). Consequently, these results demonstrated the effectiveness of the colorimetric RT-LAMP assay developed in this study as an alternative for diagnosing FCV in cats. [ABSTRACT FROM AUTHOR]

Tembusu virus (TMUV) is an important infectious disease, causing economic losses in duck production. Since the first report of TMUV infection in Vietnam in 2020, the disease has persisted and affected poultry production in the country. This study conducted epidemiological and genetic characterization of the viral strains circulating in north Vietnam based on 130 pooled tissue samples collected in six provinces/cities during 2021. The TMUV genome was examined using conventional PCR. The results indicated that 21 (16.15%) samples and 9 (23.68%) farms were positive for the viral genome. The positive rate was 59.26% for ducks at ages 2-4weeks, which was significantly higher than for ducks at ages >4weeks and<2weeks. Genetic analysis of the partial envelope gene (891bp) sequences indicated that the five Vietnamese TMUVs shared 99.55-100% nucleotide identity, while the rates were in the range 99.59-100% based on the pre-membrane gene sequences (498bp). The five Vietnamese TMUV strains obtained formed a novel single subcluster. These strains were closely related to Chinese strains and differed from the vaccine strain, suggesting that Vietnamese TMUV strains were field viruses. It needs to be further studied on vaccine development to prevent effects of TMUV infection on poultry production across Vietnam. [ABSTRACT FROM AUTHOR]

The HIV‐1 reverse transcriptase (HIV‐1 RT), which is responsible for transcription of viral RNA genomes into DNA genomes, has become an important target for the treatment of patients with HIV infection. Hydrolyzed peptides from plants are considered a new source of potential drugs. In order to develop new effective inhibitors, peptides extracted from 111 Asian medicinal plants were screened against the HIV‐1 RT. The crude hydrolyzed peptides from the fruit peel of Quercus infectoria were selected for purification and peptide sequence determination by HPLC and LC‐MS. Two peptides of interest were synthesized, and an IC50 test was performed to determine their ability to inhibit the HIV‐1 RT. The IC50 values of the peptides AIHIILI and LIAVSTNIIFIVV were determined to be 274 ± 5.10 nm and 236.4 ± 7.07 nm, respectively. This indicated that these peptides could be further developed as potential HIV‐1 RT inhibitors. [ABSTRACT FROM AUTHOR]

Feline calicivirus (FCV) is a highly contagious virus that causes upper respiratory tract disease, commonly known as cat flu. It is widely distributed worldwide and poses a major threat to feline health. Therefore, it is essential to find an efficient and rapid method for detecting FCV. In this study, the colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay, using neutral red as an indicator, was developed and validated to target the ORF2 gene of FCV for the first time. Additionally, the study compared the diagnostic abilities of polymerase chain reaction (PCR), nested PCR, and RT-LAMP assays for detecting FCV in clinical samples. The optimized RT-LAMP amplification was carried out at 56.3 °C. The technique visually detected FCV within 70 min, with a limit of detection of 14.3 × 10 1 copies/µL, and showed no cross-reactivity with other feline pathogens. Out of 54 oropharyngeal swab samples, 17 tested positive for FCV using both nested PCR and RT-LAMP, while only one tested positive using conventional PCR. The positivity rate was higher with nested PCR and RT-LAMP (31.48%) compared to conventional PCR (1.85%). Consequently, these results demonstrated the effectiveness of the colorimetric RT-LAMP assay developed in this study as an alternative for diagnosing FCV in cats.

Feline calicivirus (FCV) is a significant viral pathogen causing upper respiratory tract and oral diseases in cats. The emergence of the virulent systemic FCV variant (VS-FCV) has raised global concern in the past decade. This study aims to explore the epidemiology, genetic characterization, and diversity of FCV strains circulating among Thai cats. Various sample types, including nasal, oral, and oropharyngeal swabs and fresh tissues, were collected from 184 cats across different regions of Thailand from 2016 to 2021. Using reverse transcription real-time polymerase chain reaction (RT-qPCR), FCV infection was investigated, with additional screening for feline herpesvirus-1 (FHV-1) by qPCR. The detection rates for FCV, FHV-1, and co-infection were 46.7, 65.8, and 31.5%, respectively. Significantly, the odds ratio (OR) revealed a strong association between the detection of a single FCV and the presence of gingivostomatitis lesions (OR: 7.15, 95% CI: 1.89-26.99, p  = 0.004). In addition, FCV detection is notably less likely in vaccinated cats (OR: 0.22, 95% CI: 0.07-0.75, p  = 0.015). Amino acid sequence analysis based on the VP1 major capsid protein gene of the 14 FCV-Thai (FCV-TH) strains revealed genetic diversity compared to the other 43 global strains (0 to 86.6%). Intriguingly, a vaccine-like FCV variant was detected in one cat. In summary, this study provides insights into the epidemiology and molecular characteristics of FCV diversity within the Thai cat population for the first time. The identification of unique physicochemical characteristics in the capsid hypervariable region of some FCV-TH strains challenges previous hypotheses. Therefore, further exploration of vaccine-like FCV variants is crucial for a comprehensive understanding and to improve viral prevention and control strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Phongroop, Rattanasrisomporn, Piewbang, Tangtrongsup, Rungsipipat and Techangamsuwan.)

Background: Feline immunodeficiency virus (FIV) causes an acquired immunodeficiency-like syndrome in cats. FIV is latent. No effective treatment has been developed for treatment the infected cats. The first and second generations non-nucleoside reverse transcriptase inhibitors (NNRTIs) for HIV treatment, nevirapine (NVP) and efavirenz (EFV), and rilpivirine (RPV), were used to investigate the potential of NNRTIs for treatment of FIV infection., Objective: This study aims to use experimental and in silico approaches to investigate the potential of NNRTIs, NVP, EFV, and RPV, for inhibition of FIV reverse transcriptase (FIV-RT)., Methods: The FIV-RT and human immunodeficiency virus reverse transcriptase (HIV-RT) were expressed and purified using chromatography approaches. The purified proteins were used to determine the IC 50 values with NVP, EFV, and RPV. Surface plasmon resonance (SPR) analysis was used to calculate the binding affinities of NNRTIs to HIV-RT and FIV-RT. The molecular docking and molecular dynamic simulations were used to demonstrate the mechanism of FIV-RT and HIV-RT with first and second generation NNRTI complexes., Results: The IC 50 values of NNRTIs NVP, EFV, and RPV against FIV-RT were in comparable ranges to HIV-RT. The SPR analysis showed that NVP, EFV, and RPV could bind to both enzymes. Computational calculation also supports that these NNRTIs can bind with both FIV-RT and HIV-RT., Conclusions: Our results suggest the first and second generation NNRTIs (NVP, EFV, and RPV) could inhibit both FIV-RT and HIV-RT., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Korean Society of Veterinary Science.)

Background and Aim: Feline immunodeficiency virus (FIV) causes AIDS-like symptoms in domestic and wild cats. Treatment of infected cats has been performed using human anti-HIV drugs, which showed some limitations. This study aimed to determine the anti-FIV potential of some mushrooms., Materials and Methods: A total of 17 medicinal and edible mushrooms were screened to find their inhibitory effect against FIV reverse transcriptase (FIV-RT). Three solvents, water, ethanol, and hexane, were used to prepare crude mushroom extracts. Fluorescence spectroscopy was used to perform relative inhibition and 50% inhibitory concentrations (IC 50 ) studies., Results: The ethanol extract from dried fruiting bodies of Inonotus obliquus showed the strongest inhibition with an IC 50 value of 0.80±0.16 μg/mL. The hexane extract from dried mycelium of I. obliquus and ethanol and water extracts from fresh fruit bodies of Phellinus igniarius also exhibited strong activities with the IC 50 values of 1.22±0.20, 4.33±0.39, and 6.24±1.42 μg/mL, respectively. The ethanol extract from fresh fruiting bodies of Cordyceps sinensis , hexane extracts from dried mycelium of I. obliquus , ethanol extracts of Ganoderma lucidum , hexane extracts of fresh fruiting bodies of Morchella esculenta , and fresh fruiting bodies of C. sinensis showed moderate anti-FIV-RT activities with IC 50 values of 29.73±12.39, 49.97±11.86, 65.37±14.14, 77.59±8.31, and 81.41±17.10 μg/mL, respectively. These mushroom extracts show anti-FIV potential., Conclusion: The extracts from I. obliquus , P. igniarius , C. sinensis , and M. esculenta showed potential anti-FIV activity., (Copyright: © Seetaha, et al.)

Background and Aim: Unlike the already well-documented human serum proteome, there are still limitations regarding analyzing and interpreting the various physiological changes and disease states of the serum proteomes found in duck. Serum proteome in duck under the condition of mycotoxin contamination in feed has not yet been examined. This study aimed to introduce the characterization of the circulating proteomes in duck serum during exposure to aflatoxin B1 (AFB1)., Materials and Methods: Duck serum samples were collected from four experimental groups, gel-based mass spectrometry was then applied, and finally, 445 proteins were identified in pulled serum sample., Results: Among these 445 proteins, 377 were present in at least one group from all. There were 35 proteins which were expressed when the duck was exposed to AFB1. The protein library that allows the identification of a large number of different proteins in duck serum will be enhanced by the addition of these peptide spectral data. It is noteworthy that chromodomain-helicase-DNA-binding protein 7 (CHD7) [ Gallus gallus ] was up-regulated in the group with the highest AFB1 contamination., Conclusion: CHD7 protein might be somehow relative to aflatoxicosis in the duck that causes poor performance and economic loss. Moreover, other proteins present in duck serum were also added in the protein library., (Copyright: © Tansakul, et al.)