scholarly journals Elucidating the Venom Diversity in Sri Lankan Spectacled Cobra (Naja naja) through De Novo Venom Gland Transcriptomics, Venom Proteomics and Toxicity Neutralization

Toxins ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 558
Author(s):  
Kin Ying Wong ◽  
Kae Yi Tan ◽  
Nget Hong Tan ◽  
Christeine Ariaranee Gnanathasan ◽  
Choo Hock Tan
Keyword(s):  
Sri Lanka ◽  
De Novo ◽  
Gene Diversity ◽  
Transcript Abundance ◽  
Venom Gland ◽  
Toxin Gene ◽  
Sri Lankan ◽  
Naja Naja ◽  
Geographical Variations ◽  
Toxin Gene Expression

Inadequate effectiveness of Indian antivenoms in treating envenomation caused by the Spectacled Cobra/Indian Cobra (Naja naja) in Sri Lanka has been attributed to geographical variations in the venom composition. This study investigated the de novo venom-gland transcriptomics and venom proteomics of the Sri Lankan N. naja (NN-SL) to elucidate its toxin gene diversity and venom variability. The neutralization efficacy of a commonly used Indian antivenom product in Sri Lanka was examined against the lethality induced by NN-SL venom in mice. The transcriptomic study revealed high expression of 22 toxin genes families in NN-SL, constituting 46.55% of total transcript abundance. Three-finger toxins (3FTX) were the most diversely and abundantly expressed (87.54% of toxin gene expression), consistent with the dominance of 3FTX in the venom proteome (72.19% of total venom proteins). The 3FTX were predominantly S-type cytotoxins/cardiotoxins (CTX) and α-neurotoxins of long-chain or short-chain subtypes (α-NTX). CTX and α-NTX are implicated in local tissue necrosis and fatal neuromuscular paralysis, respectively, in envenomation caused by NN-SL. Intra-species variations in the toxin gene sequences and expression levels were apparent between NN-SL and other geographical specimens of N. naja, suggesting potential antigenic diversity that impacts antivenom effectiveness. This was demonstrated by limited potency (0.74 mg venom/ml antivenom) of the Indian polyvalent antivenom (VPAV) in neutralizing the NN-SL venom. A pan-regional antivenom with improved efficacy to treat N. naja envenomation is needed.

scholarly journals Reduced Toxicity of Centruroides vittatus (Say, 1821) May Result from Lowered Sodium β Toxin Gene Expression and Toxin Protein Production

Toxins ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 828
Author(s):  
Aimee Bowman ◽  
Chloe Fitzgerald ◽  
Jeff F. Pummill ◽  
Douglas D. Rhoads ◽  
Tsunemi Yamashita
Keyword(s):  
Gene Expression ◽  
Protein Production ◽  
Gene Diversity ◽  
Venom Gland ◽  
Scorpion Venom ◽  
Toxin Gene ◽  
Centruroides Vittatus ◽  
Venom Glands ◽  
Toxin Protein ◽  
Toxin Gene Expression

Body tissue and venom glands from an eastern population of the scorpion Centruroides vittatus (Say, 1821) were homogenized and molecular constituents removed to characterize putative sodium β toxin gene diversity, RT-qPCR, transcriptomic, and proteomic variation. We cloned sodium β toxins from genomic DNA, conducted RT-qPCR experiments with seven sodium β toxin variants, performed venom gland tissue RNA-seq, and isolated venom proteins for mass spectrophotometry. We identified >70 putative novel sodium β toxin genes, 111 toxin gene transcripts, 24 different toxin proteins, and quantified sodium β toxin gene expression variation among individuals and between sexes. Our analyses contribute to the growing evidence that venom toxicity among scorpion taxa and their populations may be associated with toxin gene diversity, specific toxin transcripts variation, and subsequent protein production. Here, slight transcript variation among toxin gene variants may contribute to the major toxin protein variation in individual scorpion venom composition.

scholarly journals Effect of Indian Polyvalent Antivenom in the Prevention and Reversal of Local Myotoxicity Induced by Common Cobra (Naja naja) Venom from Sri Lanka In Vitro

Toxins ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 308
Author(s):  
Umesha Madhushani ◽  
Prabhani Thakshila ◽  
Wayne C. Hodgson ◽  
Geoffrey K. Isbister ◽  
Anjana Silva
Keyword(s):  
Sri Lanka ◽  
Time Scale ◽  
Sri Lankan ◽  
Cellular Injury ◽  
Muscle Preparation ◽  
Naja Naja ◽  
Target Sites ◽  
Lag Period ◽  
Nerve Muscle

Bites by many Asiatic and African cobras (Genus: Naja) cause severe local dermonecrosis and myonecrosis, resulting in permanent disabilities. We studied the time scale in which two Indian polyvalent antivenoms, VINS and Bharat, remain capable of preventing or reversing in vitro myotoxicity induced by common cobra (Naja naja) venom from Sri Lanka using the chick biventer cervicis nerve-muscle preparation. VINS fully prevented while Bharat partially prevented (both in manufacturer recommended concentrations) the myotoxicity induced by Naja naja venom (10 µg/mL) when added to the organ baths before the venom. However, both antivenoms were unable to reverse the myotoxicity when added to organ baths 5 and 20 min post-venom. In contrast, physical removal of the venom from the organ baths by washing the preparation 5 and 20 min after the venom resulted in full and partial prevention of the myotoxicity, respectively, indicating the lag period for irreversible cellular injury. This suggests that, although the antivenoms contain antibodies against cytotoxins of the Sri Lankan Naja naja venom, they are either unable to reach the target sites as efficiently as the cytotoxins, unable to bind efficiently with the toxins at the target sites, or the binding with the toxins simply fails to prevent the toxin-target interactions.

scholarly journals De Novo Venom-Gland Transcriptomics of Spine-Bellied Sea Snake (Hydrophis curtus) from Penang, Malaysia—Next-Generation Sequencing, Functional Annotation and Toxinological Correlation

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 127
Author(s):  
Choo Hock Tan ◽  
Kae Yi Tan
Keyword(s):  
Next Generation Sequencing ◽  
Amino Acid ◽  
Snake Venom ◽  
De Novo ◽  
Venom Gland ◽  
Individual Species ◽  
Toxin Gene ◽  
Next Generation ◽  
Sea Snake ◽  
Generation Sequencing

Envenomation resulted from sea snake bite is a highly lethal health hazard in Southeast Asia. Although commonly caused by sea snakes of Hydrophiinae, each species is evolutionarily distinct and thus, unveiling the toxin gene diversity within individual species is important. Applying next-generation sequencing, this study investigated the venom-gland transcriptome of Hydrophis curtus (spine-bellied sea snake) from Penang, West Malaysia. The transcriptome was de novo assembled, followed by gene annotation and sequence analyses. Transcripts with toxin annotation were only 96 in number but highly expressed, constituting 48.18% of total FPKM in the overall transcriptome. Of the 21 toxin families, three-finger toxins (3FTX) were the most abundantly expressed and functionally diverse, followed by phospholipases A2. Lh_FTX001 (short neurotoxin) and Lh_FTX013 (long neurotoxin) were the most dominant 3FTXs expressed, consistent with the pathophysiology of envenomation. Lh_FTX001 and Lh_FTX013 were variable in amino acid compositions and predicted epitopes, while Lh_FTX001 showed high sequence similarity with the short neurotoxin from Hydrophis schistosus, supporting cross-neutralization effect of Sea Snake Antivenom. Other toxins of low gene expression, for example, snake venom metalloproteinases and L-amino acid oxidases not commonly studied in sea snake venom were also identified, enriching the knowledgebase of sea snake toxins for future study.

The Role of Music and Allied Arts in Public Writings on Cultural Diversity: “People of Sri Lanka”

2020 ◽  
Vol 6 ◽  
pp. 93-100
Author(s):  
Gisa Jähnichen
Keyword(s):  
Sri Lanka ◽  
Cultural Diversity ◽  
South Asia ◽  
Case Studies ◽  
Sri Lankan ◽  
Culturally Different ◽  
The World ◽  
Official Languages ◽  
The Way

The Sri Lankan Ministry of National Coexistence, Dialogue, and Official Languages published the work “People of Sri Lanka” in 2017. In this comprehensive publication, 21 invited Sri Lankan scholars introduced 19 different people’s groups to public readers in English, mainly targeted at a growing number of foreign visitors in need of understanding the cultural diversity Sri Lanka has to offer. This paper will observe the presentation of these different groups of people, the role music and allied arts play in this context. Considering the non-scholarly design of the publication, a discussion of the role of music and allied arts has to be supplemented through additional analyses based on sources mentioned by the 21 participating scholars and their fragmented application of available knowledge. In result, this paper might help improve the way facts about groups of people, the way of grouping people, and the way of presenting these groupings are displayed to the world beyond South Asia. This fieldwork and literature guided investigation should also lead to suggestions for ethical principles in teaching and presenting of culturally different music practices within Sri Lanka, thus adding an example for other case studies.

Blood Pressure values of Sri Lankan Tamils in Jaffna District, Sri Lanka

2015 ◽  
Vol 2 (3) ◽  
pp. 66-71
Author(s):  
Balasubramaniam M ◽  
◽  
Sivapalan K ◽  
Tharsha J ◽  
Sivatharushan V ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Sri Lanka ◽  
Sri Lankan ◽  
Sri Lankan Tamils

scholarly journals Venom-gland transcriptomic, venomic, and antivenomic profiles of the spine-bellied sea snake (Hydrophis curtus) from the South China Sea

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hong-Yan Zhao ◽  
Lin Wen ◽  
Yu-Feng Miao ◽  
Yu Du ◽  
Yan Sun ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Evolutionary History ◽  
De Novo ◽  
Venom Gland ◽  
The South China Sea ◽  
Protein Families ◽  
The South ◽  
Widespread Species ◽  
China Sea

Abstract Background A comprehensive evaluation of the -omic profiles of venom is important for understanding the potential function and evolution of snake venom. Here, we conducted an integrated multi-omics-analysis to unveil the venom-transcriptomic and venomic profiles in a same group of spine-bellied sea snakes (Hydrophis curtus) from the South China Sea, where the snake is a widespread species and might generate regionally-specific venom potentially harmful to human activities. The capacity of two heterologous antivenoms to immunocapture the H. curtus venom was determined for an in-depth evaluation of their rationality in treatment of H. curtus envenomation. In addition, a phylogenetic analysis by maximum likelihood was used to detect the adaptive molecular evolution of full-length toxin-coding unigenes. Results A total of 90,909,384 pairs of clean reads were generated via Illumina sequencing from a pooled cDNA library of six specimens, and yielding 148,121 unigenes through de novo assembly. Sequence similarity searching harvested 63,845 valid annotations, including 63,789 non-toxin-coding and 56 toxin-coding unigenes belonging to 22 protein families. Three protein families, three-finger toxins (3-FTx), phospholipase A2 (PLA2), and cysteine-rich secretory protein, were detected in the venom proteome. 3-FTx (27.15% in the transcriptome/41.94% in the proteome) and PLA2 (59.71%/49.36%) were identified as the most abundant families in the venom-gland transcriptome and venom proteome. In addition, 24 unigenes from 11 protein families were shown to have experienced positive selection in their evolutionary history, whereas four were relatively conserved throughout evolution. Commercial Naja atra antivenom exhibited a stronger capacity than Bungarus multicinctus antivenom to immunocapture H. curtus venom components, especially short neurotoxins, with the capacity of both antivenoms to immunocapture short neurotoxins being weaker than that for PLA2s. Conclusions Our study clarified the venom-gland transcriptomic and venomic profiles along with the within-group divergence of a H. curtus population from the South China Sea. Adaptive evolution of most venom components driven by natural selection appeared to occur rapidly during evolutionary history. Notably, the utility of commercial N. atra and B. multicinctus antivenoms against H. curtus toxins was not comprehensive; thus, the development of species-specific antivenom is urgently needed.

scholarly journals Sri Lanka: Physical Reconstruction and Economic Development as Conflict Prevention Factors

2013 ◽  
Vol 19 (69) ◽  
pp. 55-76
Author(s):  
Boženko Đevoić
Keyword(s):  
Economic Development ◽  
Sri Lanka ◽  
External Pressure ◽  
Power Sharing ◽  
Sri Lankan ◽  
Conflict Prevention ◽  
Prevention Measures ◽  
Postconflict Reconstruction ◽  
Post Conflict ◽  
The Government

ABSTRACT This article gives an overview of the 26 year long ethnic conflict in Sri Lanka and examines physical reconstruction and economic development as measures of conflict prevention and postconflict reconstruction. During the years of conflict, the Sri Lankan government performed some conflict prevention measures, but most of them caused counter effects, such as the attempt to provide “demilitarization”, which actually increased militarization on both sides, and “political power sharing” that was never honestly executed. Efforts in post-conflict physical reconstruction and economic development, especially after 2009, demonstrate their positive capacity as well as their conflict sensitivity. Although the Sri Lankan government initially had to be forced by international donors to include conflict sensitivity in its projects, more recently this has changed. The government now practices more conflict sensitivity in its planning and execution of physical reconstruction and economic development projects without external pressure.

Grasping at Straws: Judicial Review of Legislation in Sri Lanka

ICL Journal ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 281-306
Author(s):  
Danushka S Medawatte
Keyword(s):  
Sri Lanka ◽  
Transitional Justice ◽  
Judicial Review ◽  
Descriptive Analysis ◽  
Executive Power ◽  
Sri Lankan ◽  
Legal Literature ◽  
Justice Process ◽  
Provincial Councils ◽  
The Impact

AbstractIn this paper, I attempt to examine the evolution of judicial review of legislation in Sri Lanka with a view to better understanding how it has impacted the democratic fabric and constitutional matrix of Sri Lanka. The impact that judicial review of legislation has had on rights jurisprudence, enhancement of democracy, prevention of persecution against selected groups are analysed in this paper in relation to the Ceylon Constitutional Order in Council of 1946 (‘Soulbury’ Constitution) and the two autochthonous constitutions of Sri Lanka of 1972 and 1978. The first part of the paper comprises of a descriptive analysis of judicial review of legislation under the three Constitutions. This is expected to perform a gap filling function in respect of the lacuna that exists in Sri Lankan legal literature in relation to the assessment of the trends pertaining to judicial review of legislation in Sri Lanka. In the second part of the paper, I have analysed decided cases of Sri Lanka to explore how the judiciary has responded to legislative and executive power, and has given up or maintained judicial independence. In this respect, I have also attempted to explore whether the judiciary has unduly engaged in restraint thereby impeding its own independence. The third part of the paper evaluates the differences in technique and stance the judiciary has adopted when reviewing draft enactments of the national legislature and when reviewing draft or enacted statutes of Provincial Councils. From a comparative constitutional perspective, this assessment is expected to provide the background that is essential in understanding the island nation’s current constitutional discourse, transitional justice process, and its approach to human rights.

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