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1.
PLoS One ; 18(9): e0291763, 2023.
Article in English | MEDLINE | ID: mdl-37729154

ABSTRACT

Cinnamomum species have gained worldwide attention because of their economic benefits. Among them, C. verum (synonymous with C. zeylanicum Blume), commonly known as Ceylon Cinnamon or True Cinnamon is mainly produced in Sri Lanka. In addition, Sri Lanka is home to seven endemic wild cinnamon species, C. capparu-coronde, C. citriodorum, C. dubium, C. litseifolium, C. ovalifolium, C. rivulorum and C. sinharajaense. Proper identification and genetic characterization are fundamental for the conservation and commercialization of these species. While some species can be identified based on distinct morphological or chemical traits, others cannot be identified easily morphologically or chemically. The DNA barcoding using rbcL, matK, and trnH-psbA regions could not also resolve the identification of Cinnamomum species in Sri Lanka. Therefore, we generated Illumina Hiseq data of about 20x coverage for each identified species and a C. verum sample (India) and assembled the chloroplast genome, nuclear ITS regions, and several mitochondrial genes, and conducted Skmer analysis. Chloroplast genomes of all eight species were assembled using a seed-based method.According to the Bayesian phylogenomic tree constructed with the complete chloroplast genomes, the C. verum (Sri Lanka) is sister to previously sequenced C. verum (NC_035236.1, KY635878.1), C. dubium and C. rivulorum. The C. verum sample from India is sister to C. litseifolium and C. ovalifolium. According to the ITS regions studied, C. verum (Sri Lanka) is sister to C. verum (NC_035236.1), C. dubium and C. rivulorum. Cinnamomum verum (India) shares an identical ITS region with C. ovalifolium, C. litseifolium, C. citriodorum, and C. capparu-coronde. According to the Skmer analysis C. verum (Sri Lanka) is sister to C. dubium and C. rivulorum, whereas C. verum (India) is sister to C. ovalifolium, and C. litseifolium. The chloroplast gene ycf1 was identified as a chloroplast barcode for the identification of Cinnamomum species. We identified an 18 bp indel region in the ycf1 gene, that could differentiate C. verum (India) and C. verum (Sri Lanka) samples tested.


Subject(s)
Cinnamomum , Genome, Chloroplast , Genome, Mitochondrial , Cinnamomum/genetics , Sri Lanka , Bayes Theorem , Cinnamomum zeylanicum
2.
Parasitol Int ; 77: 102129, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32339713

ABSTRACT

Here we report three cases of canine trypanosomosis presented to the Veterinary Teaching Hospital in the Faculty of Veterinary Medicine and Animal Sciences at the University of Peradeniya, Sri Lanka during 2018. The cases were presented to the hospital when the dogs were already in critical condition. Confirmation of the cases was done by microscopic examination of Giemsa-stained thin blood smears. All three dogs had bilateral keratitis and anterior chamber cloudiness in eyes. Despite the intramuscular administration of diminazine aceturate, all of them subsequently died. Amplification and sequencing of a fragment of the internal transcribed spacer 1 (ITS1) of the nuclear ribosomal DNA confirmed the parasite as Trypanosoma. evansi. This is the first record of clinical cases of canine trypanosomosis in Sri Lanka. The three cases reported here came from widely separated geographical locations within the country: Balangoda, Mullaitivu and Kadawatha.


Subject(s)
Dog Diseases/parasitology , Trypanosoma/classification , Trypanosomiasis/diagnosis , Trypanosomiasis/veterinary , Animals , DNA, Ribosomal Spacer/genetics , Dog Diseases/diagnosis , Dogs , Eye/parasitology , Geography , Keratitis/parasitology , Male , Phylogeny , Sri Lanka , Trypanosoma/isolation & purification , Trypanosomiasis/parasitology
3.
BMC Chem ; 14(1): 18, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32190844

ABSTRACT

Chemical investigation of the essential oil obtained from the heartwood of Erythroxylum monogynum Roxb. yielded three beyerene type diterpenoids ent-beyer-15-ene (1), ent-beyer-15-en-19-ol (erythroxylol A) (2) and ent-beyer-15-en-19-al (3). Ent-beyer-15-en-19-al (3) was found to be unstable at room temperature, giving rise to hitherto unknown 15,16-epoxy-ent-beyeran-19-oic acid (4). This conversion involves the auto-oxidation of a C-4 axial aldehyde group of an ent-beyer-15-ene diterpenoid with the concurrent epoxidation of the C-15 double bond. This is the first report of the auto-oxidation of an aldehyde group to a carboxylic acid group with the concurrent epoxidation of a double bond in the same compound. Further investigation of this observation under controlled conditions resulted in the isolation and identification of ent-beyer-15-en-19-oic acid (5), two new epoxy hydroperoxides, 15,16-epoxy-19-nor-ent-beyeran-4α-hydroperoxide (6a), 15,16-epoxy-18-nor-ent-beyeran-4ß-hydroperoxide (6b), and two new hydroperoxides, ent-beyer-19-nor-15-en-4α-hydroperoxide (7), ent-beyer-18-nor-15-en-4ß-hydroperoxide (8) and ent-beyer-18-nor-15-en-4ß-ol (9). Identification of these compounds was carried out by the extensive usage of spectroscopic data including 1D and 2D NMR. The acid 5 and the alcohol 9 have been reported previously as natural products from Elaeoselinum asclepium and Erythroxylum monogynum. The mechanistic basis of this auto-oxidation reaction is discussed.

4.
Sci Adv ; 5(12): eaax2388, 2019 12.
Article in English | MEDLINE | ID: mdl-31844662

ABSTRACT

The causal association of Zika virus (ZIKV) with microcephaly, congenital malformations in infants, and Guillain-Barré syndrome in adults highlights the need for effective vaccines. Thus far, efforts to develop ZIKV vaccines have focused on the viral envelope. ZIKV NS1 as a vaccine immunogen has not been fully explored, although it can circumvent the risk of antibody-dependent enhancement of ZIKV infection, associated with envelope antibodies. Here, we describe a novel DNA vaccine encoding a secreted ZIKV NS1, that confers rapid protection from systemic ZIKV infection in immunocompetent mice. We identify novel NS1 T cell epitopes in vivo and show that functional NS1-specific T cell responses are critical for protection against ZIKV infection. We demonstrate that vaccine-induced anti-NS1 antibodies fail to confer protection in the absence of a functional T cell response. This highlights the importance of using NS1 as a target for T cell-based ZIKV vaccines.


Subject(s)
Epitopes/immunology , Vaccines, DNA/immunology , Viral Nonstructural Proteins/immunology , Zika Virus Infection/immunology , Animals , DNA/genetics , DNA/immunology , Disease Models, Animal , Guillain-Barre Syndrome/genetics , Guillain-Barre Syndrome/immunology , Guillain-Barre Syndrome/virology , Humans , Mice , T-Lymphocytes/immunology , T-Lymphocytes/virology , Viral Nonstructural Proteins/genetics , Zika Virus/immunology , Zika Virus/pathogenicity , Zika Virus Infection/prevention & control , Zika Virus Infection/virology
5.
Sci Rep ; 9(1): 9251, 2019 06 25.
Article in English | MEDLINE | ID: mdl-31239471

ABSTRACT

The introduction of directly acting antiviral agents (DAAs) has produced significant improvements in the ability to cure chronic hepatitis C infection. However, with over 2% of the world's population infected with HCV, complications arising from the development of cirrhosis of the liver, chronic hepatitis C infection remains the leading indication for liver transplantation. Several modelling studies have indicated that DAAs alone will not be sufficient to eliminate HCV, but if combined with an effective vaccine this regimen would provide a significant advance towards achieving this critical World Health Organisation goal. We have previously generated a genotype 1a, 1b, 2a, 3a HCV virus like particle (VLP) quadrivalent vaccine. The HCV VLPs contain the core and envelope proteins (E1 and E2) of HCV and the vaccine has been shown to produce broad humoral and T cell immune responses following vaccination of mice. In this report we further advanced this work by investigating vaccine responses in a large animal model. We demonstrate that intradermal microneedle vaccination of pigs with our quadrivalent HCV VLP based vaccine produces long-lived multi-genotype specific and neutralizing antibody (NAb) responses together with strong T cell and granzyme B responses and normal Th1 and Th2 cytokine responses. These responses were achieved without the addition of adjuvant. Our study demonstrates that our vaccine is able to produce broad immune responses in a large animal that, next to primates, is the closest animal model to humans. Our results are important as they show that the vaccine can produce robust immune responses in a large animal model before progressing the vaccine to human trials.


Subject(s)
Antibodies, Neutralizing/immunology , Drug Delivery Systems , Hepacivirus/drug effects , Hepatitis C Antibodies/immunology , Hepatitis C/prevention & control , Viral Envelope Proteins/immunology , Viral Hepatitis Vaccines/administration & dosage , Animals , Drug Evaluation, Preclinical , Hepacivirus/immunology , Hepatitis C/virology , Swine , Vaccination
6.
Vaccine ; 37(10): 1266-1276, 2019 02 28.
Article in English | MEDLINE | ID: mdl-30733092

ABSTRACT

This study demonstrates that route and viral vector can significantly influence the innate lymphoid cells (ILC) and dendritic cells (DC) recruited to the vaccination site, 24 h post delivery. Intranasal (i.n.) vaccination induced ST2/IL-33R+ ILC2, whilst intramuscular (i.m.) induced IL-25R+ and TSLPR+ (Thymic stromal lymphopoietin protein receptor) ILC2 subsets. However, in muscle a novel ILC subset devoid of the known ILC2 markers (IL-25R- IL-33R- TSLPR-) were found to express IL-13, unlike in lung. Different viral vectors also influenced the ILC-derived cytokines and the DC profiles at the respective vaccination sites. Both i.n. and i.m. recombinant fowlpox virus (rFPV) priming, which has been associated with induction of high avidity T cells and effective antibody differentiation exhibited low ILC2-derived IL-13, high NKp46+ ILC1/ILC3 derived IFN-γ and low IL-17A, together with enhanced CD11b+ CD103- conventional DCs (cDC). In contrast, recombinant Modified Vaccinia Ankara (rMVA) and Influenza A vector priming, which has been linked to low avidity T cells, induced opposing ILC derived-cytokine profiles and enhanced cross-presenting DCs. These observations suggested that the former ILC/DC profiles could be a predictor of a balanced cellular and humoral immune outcome. In addition, following i.n. delivery Rhinovirus (RV) and Adenovius type 5 (Ad5) vectors that induced elevated ILC2-derived IL-13, NKp46+ ILC1/ILC3-derived-IFN-γ and no IL-17A, predominantly recruited CD11b- B220+ plasmacytoid DCs (pDC). Knowing that pDC are involved in antibody differentiation, we postulate that i.n. priming with these vectors may favour induction of effective humoral immunity. Our data also revealed that vector-specific replication status and/or presence or absence of immune evasive genes can significantly alter the ILC and DC activity. Collectively, our findings suggest that understanding the route- and vector-specific ILC and DC profiles at the vaccination site may help tailor/design more efficacious viral vector-based vaccines, according to the pathogen of interest.


Subject(s)
Dendritic Cells/immunology , Lymphocytes/immunology , Vaccines, Synthetic/administration & dosage , Viruses/genetics , Administration, Intranasal , Animals , Cytokines/immunology , Female , Immunity, Cellular , Immunity, Humoral , Injections, Intramuscular , Mice , Mice, Inbred BALB C , Vaccination , Vaccines, Synthetic/immunology , Viruses/immunology
7.
Vaccine ; 34(46): 5488-5494, 2016 11 04.
Article in English | MEDLINE | ID: mdl-27742218

ABSTRACT

DNA vaccines are ideal candidates for global vaccination purposes because they are inexpensive and easy to manufacture on a large scale such that even people living in low-income countries can benefit from vaccination. However, the potential of DNA vaccines has not been realized owing mainly to the poor cellular uptake of DNA in vivo resulting in the poor immunogenicity of DNA vaccines. In this review, we discuss the benefits and shortcomings of several promising and innovative non-biological methods of DNA delivery that can be used to increase cellular delivery and efficacy of DNA vaccines.


Subject(s)
Immunogenicity, Vaccine , Vaccination/methods , Vaccines, DNA , Animals , Antigen-Presenting Cells/immunology , Biolistics , Electroporation , Humans , Injections, Intramuscular , Liposomes , Mice , Subcutaneous Absorption
8.
Gene Ther ; 23(1): 26-37, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26262584

ABSTRACT

Currently, no vaccine is available against hepatitis C virus (HCV), and although DNA vaccines have considerable potential, this has not been realised. Previously, the efficacy of DNA vaccines for human immunodeficiency virus (HIV) and HCV was shown to be enhanced by including the gene for a cytolytic protein, viz. perforin. In this study, we examined the mechanism of cell death by this bicistronic DNA vaccine, which encoded the HCV non-structural protein 3 (NS3) under the control of the CMV promoter and perforin is controlled by the SV40 promoter. Compared with a canonical DNA vaccine and a bicistronic DNA vaccine encoding NS3 and the proapoptotic gene NSP4, the perforin-containing vaccine elicited enhanced cell-mediated immune responses against the NS3 protein in vaccinated mice and pigs, as determined by ELISpot and intracellular cytokine staining, whereas a mouse challenge model suggested that the immunity was CD8(+) T-cell-dependent. The results of the study showed that the inclusion of perforin in the DNA vaccine altered the fate of NS3-positive cells from apoptosis to necrosis, and this resulted in more robust immune responses in mice and pigs, the latter of which represents an accepted large animal model in which to test vaccine efficacy.


Subject(s)
DNA, Viral/genetics , Hepacivirus , Immunity, Cellular , Perforin/genetics , Vaccines, DNA/immunology , Viral Nonstructural Proteins/genetics , Animals , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cell Line, Tumor , DNA, Viral/isolation & purification , Disease Models, Animal , Enzyme-Linked Immunospot Assay , Glycoproteins/genetics , Glycoproteins/immunology , HEK293 Cells , Humans , Immunization , Male , Mice , Perforin/immunology , Promoter Regions, Genetic , Swine , Toxins, Biological/genetics , Toxins, Biological/immunology , Vaccines, DNA/genetics , Viral Nonstructural Proteins/immunology
9.
Ann Bot ; 108(8): 1489-502, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21831853

ABSTRACT

BACKGROUND AND AIMS: The Borasseae form a highly supported monophyletic clade in the Arecaceae-Coryphoideae. The fruits of Coryphoideae are small, drupaceous with specialized anatomical structure of the pericarp and berries. The large fruits of borassoid palms contain massive pyrenes, which develop from the middle zone of the mesocarp. The pericarp structure and mode of its development in Borasseae are similar to those of Eugeissona and Nypa. A developmental carpological study of borassoid palms will allow us to describe the process of pericarp development and reveal the diagnostic fruit features of borassoid palms, determine the morphogenetic fruit type in Borasseae genera, and describe similarities in fruit structure and pericarp development with other groups of palms. METHODS: The pericarp anatomy was studied during development with light microscopy based on the anatomical sections of fruits of all eight Borasseae genera. KEY RESULTS: The following general features of pericarp structure in Borasseae were revealed: (1) differentiation of the pericarp starts at early developmental stages; (2) the exocarp is represented by a specialized epidermis; (3) the mesocarp is extremely multilayered and is differentiated into several topographical zones - a peripheral parenchymatous zone(s) with scattered sclerenchymatous elements and vascular bundles, a middle zone (the stony pyrene comprising networks of elongated sclereids and vascular bundles) and an inner parenchymatous zone(s); (4) differentiation and growth of the pyrene tissue starts at early developmental stages and ends long before maturation of the seed; (5) the inner parenchymatous zone(s) of the mesocarp is dramatically compressed by the mature seed; (6) the endocarp (unspecialized epidermis) is not involved in pyrene formation; and (7) the spermoderm is multilayered in Hyphaeninae and obliterated in Lataniinae. CONCLUSIONS: The fruits of Borasseae are pyrenaria of Latania-type. This type of pericarp differentiation is also found only in Eugeissona and Nypa. The fruits of other Coryphoideae dramatically differ from Borasseae by the pericarp anatomical structure and the mode of its development.


Subject(s)
Arecaceae/anatomy & histology , Arecaceae/growth & development , Fruit/anatomy & histology , Fruit/growth & development , Plant Epidermis/growth & development , Seeds/growth & development
10.
Phytochemistry ; 56(8): 857-61, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11324918

ABSTRACT

Two benzophenanthrene alkaloids, 8-acetonyldihydronitidine and 8-acetonyldihydroavicine were isolated from Zanthoxylum tetraspermum stem bark along with liriodenine, sesamin, lichexanthone and (+)-piperitol-gamma,gamma-dimethylallylether. The species endemic to Sri Lanka, Z. caudatum, contained sesamin, savinin, liriodenine, decarine and 8-O-desmethyl-N-nornitidine. 8-Acetonyldihydronitidine and 8-acetonyldihydroavicine showed significant antibacterial activity while the former along with liriodenine was strongly antifungal. Savinin exhibited potent spermicidal activity. Both savinin and sesamin exhibited significant insecticidal activity.


Subject(s)
Alkaloids/isolation & purification , Anti-Infective Agents/isolation & purification , Phenanthrenes/isolation & purification , Rosales/chemistry , Alkaloids/chemistry , Alkaloids/pharmacology , Anti-Infective Agents/chemistry , Phenanthrenes/chemistry , Phenanthrenes/pharmacology
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