Publications by authors named "Yan Ru Choi"

Leptospirosis is a bacterial zoonotic disease of major One Health significance and public health impact globally, with a wide host range including mammals, cetaceans and herpetofauna. This study aimed to determine seroprevalence, risk factors for seroreactivity and prevalence of urinary shedding among domestic cats in Hong Kong. Microagglutination testing of 22 serovars from 20 serogroups was performed on 738 sera from outdoor free-roaming "community" cats ( = 391) and privately-owned ( = 347) cats.

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This case series investigates a cluster of deaths in a captive colony of Leschenault's rousettes (). Six of seven bats that died between March and September 2021 were diagnosed postmortem with both iron overload (IO) and neoplasia, neither of which have previously been reported in this species. Iron status was assessed via hepatic histopathological grading, hepatic iron concentration, and, in two cases, serum iron concentration.

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Understanding the local epidemiology of feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) in Hong Kong will inform retrovirus prevention strategies. Domestic cat hepadnavirus (DCH), a novel hepatitis-B-like virus, is commonly detected among client-owned cats in Hong Kong, but community cats have not been studied. The aims of this study were to investigate the frequency and potential risk factors for (i) FeLV and FIV among community and client-owned cats and (ii) perform molecular detection of DCH among community cats in Hong Kong.

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Cat ownership is common in Chile, but data on the regional prevalence of infectious agents are limited. A sero-molecular survey of 120 client- or shelter-owned domestic cats in greater Santiago was performed. Whole blood DNA was tested for the novel hepatitis-B-like virus, domestic cat hepadnavirus (DCH) by conventional PCR (cPCR) and quantitative PCR (qPCR), and for feline leukaemia virus (FeLV) by qPCR.

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Article Synopsis
  • - SARS-CoV-2, the virus causing COVID-19, has raised concerns about its ability to infect animals, prompting studies in densely populated cities like Hong Kong and Seoul to assess exposure in cats and dogs.
  • - Testing of 1040 cats and 855 dogs for SARS-CoV-2 antibodies revealed a low percentage of positive results, with higher rates in dogs compared to cats and very few showing neutralizing antibodies.
  • - The study indicates that while there is some exposure to the virus in companion animals, the low seroprevalence suggests limited transmission, and discrepancies in test results could point to cross-reactivity with other coronaviruses.
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Domestic cat hepadnavirus (DCH) is an emerging virus related to the hepatitis B virus (HBV). The pathogenic potential of DCH in cats remains to be established. The molecular prevalence of DCH varies widely in the regions investigated so far.

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Chronic hepatitis and hepatocellular carcinoma (HCC) caused by the hepadnavirus hepatitis B virus (HBV) are significant causes of human mortality. A hepatitis-B-like virus infecting cats, domestic cat hepadnavirus (DCH), was reported in 2018. DCH DNA is hepatotropic and detectable in feline blood or serum (3.

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Solid silicon nanowires and their luminescent properties have been widely studied, but lesser is known about the optical properties of mesoporous silicon nanowires (mp-SiNWs). In this work, we present a facile method to generate greenish-blue photoluminescence (GB-PL) by fast scanning a focused green laser beam (wavelength of 532 nm) on a close-packed array of mp-SiNWs to carry out photo-induced chemical modification. The threshold of laser power is 5 mW to excite the GB-PL, whose intensity increases with laser power in the range of 5-105 mW.

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