Publications by authors named "Tein-Shun Tsai"

Snakebite envenomation is a significant global health issue that requires specific antivenom treatments. In Taiwan, available antivenoms target a variety of snakes, but none specifically target Trimeresurus gracilis, an endemic and protected species found in the high mountain areas of Taiwan. This study evaluated the effectiveness of existing antivenoms against T.

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Article Synopsis
  • Deinagkistrodon acutus, a pitviper found mostly in South China and Taiwan, has venom rich in metalloproteases and C-type lectin-like proteins that can cause severe bleeding.
  • This study explored the differences in venom composition between specimens from Taiwan and four provinces in Mainland China using various biochemical methods, finding distinct variations in venom proteins and their expression.
  • The Taiwanese D. acutus venom showed higher reactivity with a specific antivenom compared to Mainland Chinese venoms, and there was noted cross-reactivity with Crotalus horridus venom, which suggests similarities in certain venom components.
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The oral cavity of snakes serves as a habitat for various microorganisms, some of which may include potential zoonotic pathogens posing risks to hosts and causing wound infections in snakebite victims. Clinical studies on snakebite cases in Taiwan have identified specific pathogens, such as (Gram-positive), , , and (Gram-negative). However, the prevalence of these bacteria in the oral cavity of wild snakes remains largely unknown.

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Snakebite envenomation is a neglected tropical disease. Taiwan, with its subtropical and Southeast Asian environment, provides suitable habitat for several venomous snake species. Trimeresurus stejnegeri, an arboreal pit viper, is the most common cause of venomous snakebite in Taiwan.

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A venomous snake's oral cavity may harbor pathogenic microorganisms that cause secondary infection at the wound site after being bitten. We collected oral samples from 37 individuals belonging to seven species of wild venomous snakes in Taiwan, including (Na), (Bm), (Pm), (Ts), (Ds), (Da), and alpine (Tg). Bacterial species were identified using full-length 16S rRNA amplicon sequencing analysis, and this is the first study using this technique to investigate the oral microbiota of multiple Taiwanese snake species.

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is an endemic alpine pitviper in Taiwan with controversial phylogeny, and its venom proteome remains unknown. In this study, we conducted a proteomic analysis of venom using high-performance liquid chromatography-tandem mass spectrometry and identified 155 toxin proteoforms that belong to 13 viperid venom toxin families. By searching the sequences of trypsin-digested peptides of the separated HPLC fractions against the NCBI database, venom was found to contain 40.

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The cDNAs encoding the Zn-metalloproteases (SVMPs) of Trimeresurus gracilis (abbreviated as Tgc), a pitviper endemic to Taiwan, were cloned from venom glands and sequenced. The amino-acid sequences of five novel SVMPs, including one P-III, three P-II and one P-I class enzymes, were thus deduced and subjected to BLAST-analyses. The P-III enzyme (designated as Tgc-PIII) is structurally most similar to the PIII-SVMPs of New World pitvipers but not similar to the PIII-SVMP of Ovophis okinavensis.

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Wound infections after venomous snakebites are clinically important. Information regarding the nature and antibiotic susceptibilities of snake oral bacterial flora could support empiric antibiotic therapy. Wild venomous snakes were collected from southern Taiwan: a total of 30 each of Bungarus multicinctus, Naja atra, Protobothrops mucrosquamatus, and Trimeresurus stejnegeri; 3 Deinagkistrodon acutus; and 4 Daboia siamensis.

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Trimeresurus gracilis is a pit viper inhabiting the high mountains of Taiwan. No specific antivenom against T. gracilis is available, and we did not find any prior published case reports on its clinical envenomation.

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Reports of envenomation induced by , a medically important venomous snake in Taiwan, are rare, and species identification might not be definitive. This article reports the complete course of a definite bite. The patient in this report was one of the authors who was bitten on the right palm near the base of the index finger by The patient experienced local effects, neurological manifestations, and acute kidney injury.

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Trimeresurus gracilis (Tgc) is endemic to Taiwan and shown to be closely related with Ovophis okinavensis by previous phylogenetic analyses, but their taxonomic status remain controversial. Here, we cloned and sequenced ten of its venom serine-proteases (designated as Tgc-vSPs). All the Tgc-vSPs conserve the catalytic triads, six appear to be kallikrein-like (KNs) and four are plasminogen-activator homologs (PAHs and PAs).

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Unlike other snakes, most species of possess glands in their dorsal skin, sometimes limited to the neck, known as nucho-dorsal and nuchal glands, respectively. Those glands contain powerful cardiotonic steroids known as bufadienolides, which can be deployed as a defense against predators. Bufadienolides otherwise occur only in toads (Bufonidae) and some fireflies (Lampyrinae), which are known or believed to synthesize the toxins.

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A large body of evidence indicates that evolutionary innovations of novel organs have facilitated the subsequent diversification of species. Investigation of the evolutionary history of such organs should provide important clues for understanding the basis for species diversification. An Asian natricine snake, , possesses a series of unusual organs, called nuchal glands, which contain cardiotonic steroid toxins known as bufadienolides.

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Few convenient/expeditious methods for identifying the species of shed snake skins in specific areas have been developed. The scales on shed snake skins are permeable to light and can be examined by light microscopy (LM), which is of higher availability-especially for wild animal researchers and citizen scientists-than conventional approach which examines the scale microstructures by scanning electron microscopy. We collected and examined a total of 801 shed samples or scale specimens from 53 snake species in Taiwan and adjacent islands, and developed the first guide to identify the fragmented or faded shed skins of most snake species by LM.

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The genus Laticauda (Reptilia: Elapidae), commonly known as sea kraits, is venomous marine amphibious snakes distributed throughout the south and southeast Asian islands and mostly found in coastal waters. To facilitate genetic studies, we have developed microsatellite loci for L. semifasciata using the 454 GS-FLX pyrosequencing technique.

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Morphometric measurements are basic but essential data in morphological and ecological research. It is thus beneficial to develop a safe, convenient, multipurpose device/technique to determine body length and physical characteristics of living snakes with high accuracy/precision and low stress, and to enable the probing of snakes and collection of tissue samples. To meet these requirements, we developed an improved technique, which we named the Confining-Box Method (CBM).

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Shed snake skins have many applications for humans and other animals, and can provide much useful information to a field survey. When properly prepared and identified, a shed snake skin can be used as an important voucher; the morphological descriptions of the shed skins may be critical for taxonomic research, as well as studies of snake ecology and conservation. However, few convenient/ expeditious methods or techniques to identify shed snake skins in specific areas have been developed.

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To investigate the phylogenetic relationships of the genus Laticauda to related higher taxa, we compared the sequences of four mitochondrial genes (12S rRNA, 16S rRNA, ND4, Cytb) from three Laticauda species (L. colubrina, L. laticaudata, and L.

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Marine reptiles are declining globally, and recent climate change may be a contributing factor. The study of sea snakes collected beyond their typical distribution range provides valuable insight on how climate change affects marine reptile populations. Recently, we collected 12 Laticauda semifasciata (11 females, 1 male) from the waters around southern South Korea-an area located outside its typical distribution range (Japan, China including Taiwan, Philippines and Indonesia).

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Article Synopsis
  • - This study analyzes how king cobra venom varies geographically using samples from Indonesia, Malaysia, Thailand, and two provinces of China, revealing that Chinese venoms are more lethal to mice while Southeast Asian venoms are more deadly to lizards.
  • - The researchers identified various toxic components in the venom, including novel phospholipases and different sets of three-finger toxins (3FTxs) unique to each region, while certain inhibitors were exclusive to the Chinese samples.
  • - The findings suggest that the venom has rapidly evolved to suit different prey, which could affect how king cobra bites impact humans and emphasizes the need for localized antivenin treatments.
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This study focuses on the structural and functional characterizations of novel venom phospholipases A(2) (PLA(2)s) from Trimeresurus gracilis, an endemic Taiwanese pitviper. The PLA(2) cDNAs were cloned from venom glands and sequenced. The majority of the clones encoded a Glu6-containing PLA(2) (designated as Tgc-E6) whose deduced amino acid sequence resembled those of other Crotalinae acidic PLA(2)s.

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With bioenergetic modeling, we tested the hypothesis that reptiles maximize net energy gain by postprandial thermal selection. Previous studies have shown that Chinese green tree vipers (Trimeresurus s. stejnegeri) have postprandial thermophily (mean preferred temperature T(p) for males =27.

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It has been a common belief that snake venom may help in the digestion of its prey, although direct examples and supporting evidence have not been sufficient. To address this, the present study examined whether preinjecting natural amounts of pit viper venom into experimental mice may accelerate their digestion by the snakes or gain energy benefit as compared to the control without the envenomation. Live adults of two Asian pit viper species Trimeresurus gracilis and T.

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Phospholipases A2 (PLA2s) were purified from the Trimeresurus stejnegeri venom obtained from various localities in Taiwan and three provinces in China, by gel filtration followed by reversed-phase HPLC. The precise molecular mass and N-terminal sequence of each PLA2 were determined. In addition to the six previously documented PLA2 isoforms of this species, we identified ten novel isoforms.

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