Browsing by Author "Chitra, M. Ananda"
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ArticleItem Open Access Anti-Bacterial Activity Of Silver Nanoparticles Synthesized using Phyllanthus Amarus Aqueous & Andrographis Paniculata Ethanolic Extracts(TANUVAS, Chennai, 2015-01) Chitra, M. Ananda; Ramesh, S.; TANUVASThe use of metallic silver as an antimicrobial agent has been recognized for centuries. Silver nanoparticles (SNP) are now incorporated in apparel, wound dressings, appliances, cosmetics, paints and plastics for their antimicrobial properties. Generally, silver nanoparticles are prepared by a variety of chemical methods. In this study, we have used Phyllanthus amarus and Andrographis paniculata herbal plants leaves and stem extracts to synthesis SNP and were characterized by UV-Vis spectroscopy and Transmission Electron Microscopy (TEM). SNP capped with plant extracts gave absorption peak at 420 nm as expected for silver and broadening of peak were also noticed. TEM images suggested that they were of almost spherical shape and in the range of 7-60 nm in size. Antibacterial activity of plant extracts capped SNP were tested in Mueller-Hinton agar by well diffusion method against Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, Escherichia coli and Salmonella Typhimurium. SNP of 1 mg/ml and 5 mg/ml of P.amarus exhibited almost similar antibacterial activity, whereas, 5mg/ml, not 1 mg/ml of SNP capped with A.paniculata exerted antibacterial activity. The highest zone of inhibition was noticed against B.subtilis followed by S.aureus and P.vulgaris and the least zone of inhibition was observed against E.coli and S.Typhimurium. Green synthesis of SNP is cost effective and environment friendly. Further studies are required to explore the possibility of use of P.amarus capped silver nanoparticles for the treatment of burn and wound.ArticleItem Open Access Biosafety Concerns During the Collection, Transportation, and Processing of COVID-19 Samples for Diagnosis(2020) Karthik, K.; Aravindh Babu, RP; Dhama, K.; Chitra, M. Ananda; Kalaiselvi, G.; Senthilkumar, TMA; Raj, G. Dhinakar; TANUVASThe coronavirus disease 2019 (COVID-19) pandemic, which started in China, has created a panic among the general public and health care/laboratory workers. Thus far, there is no medication or vaccine to prevent and control the spread of COVID-19. As the virus is airborne and transmitted through droplets, there has been significant demand for face masks and other personal protective equipment to prevent the spread of infection. Health care and laboratory workers who come in close contact with infected people or material are at a high risk of infection. Therefore, robust biosafety measures are required at hospitals and laboratories to prevent the spread of COVID-19. Various diagnostic platforms including of serological, molecular and other advanced tools and techniques have been designed and developed for rapid detection of SARS-CoV-2 and each has its own merits and demerits. Molecular assays such as real-time reverse transcriptase polymerase chain reaction (rRT-PCR) has been used worldwide for diagnosis of COVID-19. Samples such as nasal swabs or oropharyngeal swabs are used for rRT-PCR. Laboratory acquired infection has been a significant problem worldwide, which has gained importance during the current pandemic as the samples for rRT-PCR may contain intact virus with serious threat. COVID-19 can spread to workers during the sampling, transportation, processing, and disposal of tested samples. Here, we present an overview on advances in diagnosis of COVID-19 and details the issues associated with biosafety procedures and potential safety precautions to be followed during collection, transportation, and processing of COVID-19 samples for laboratory diagnosis so as to avoid virus infection.ArticleItem Open Access Cytokine response to killed Staphylococcus pseudintermedius antigen in dogs with skin diseases(Agricultural Research Communication Centre, 2018) Varughese, Hridya Susan; Chitra, M. Ananda; Rajasekaran, Ranjani; Rajalakshmi, S; Raj, G Dhinakar; TANUVASThe attempt was made to study the response of the dog having skin infection with various underlying causes to killed S.pseudintermedius antigen. PBMC were separated and sensitized with killed S. pseudintermedius for 24 hours. cDNA was made from extracted RNA and quantitative PCR were carried out for 8 cytokines with GAPDH as housekeeping gene. IL-6 was the cytokine which was expressed in a statistically significant high level in PBMC of healthy animals to killed antigen than PBMC of infected animals. Except for the IL-6, all other cytokines were expressed at high level in pyoderma animals than healthy control, demodicosis and allergy cases. In the present study, IL-1β, IL-8 and TNF-α were the cytokines that were up-regulated and, IL-6 and IFN-γ were down-regulated in demodicosis dogs with pyoderma at apparently significant level than the other tested cytokines. IL-4 was the only cytokine that was expressed in measurable quantity in allergic cases when compared to other cytokines. Thus, it was concluded that dogs with staphylococcal pyoderma infections developed a Th1/Th2 response to fight the infection.ArticleItem Open Access Dermatophilus congolensis infection in sheep and goats in Delta region of Tamil Nadu(2017-11) Chitra, M. Ananda; Jayalakshmi, K.; Ponnusamy, P.; Manickam, R.; Ronald, B.S.M.; TANUVASAim: The study was conducted to isolate and identify Dermatophilus congolensis (DC) using conventional and molecular diagnostic techniques in scab materials collected from skin infections of sheep and goats in the Delta region of Tamil Nadu. Materials and Methods: A total of 20 scab samples collected from 18 goats and 2 sheep from Nagapattinam, Thanjavur, and Tiruvarur districts of Tamil Nadu. Smears were made from softened scab materials and stained by either Gram’s or Giemsa staining. Isolation was attempted on blood agar plates, and colonies were stained by Gram’s staining for morphological identification. Identification was also done by biochemical tests and confirmed by 16S rRNA polymerase chain reaction (PCR), followed by sequencing and phylogenetic analysis of the amplified product. Results: The peculiar laddering arrangement of coccoid forms in stained smears prepared from scab materials revealed the presence of DC. Isolated colonies from scab materials of sheep and goats on bovine blood agar plate were small, hemolytic, rough, adherent, and bright orange-yellow in color, but some colonies were white to cream color. Gram-staining of cultured organisms revealed Gram-positive branching filaments with various disintegration stages of organisms. 16S rRNA PCR yielded 500 bp amplicon specific for DC. Sequence analysis of a sheep DC isolate showed 99-100% sequence homology with other DC isolates available in NCBI database, and phylogenetic tree showed a close cluster with DC isolates of Congo, Nigeria, and Angola of Africa. Genes for virulence factors such as serine protease and alkaline ceramidase could not be detected by PCR in any of the DC strains isolated of this study. Conclusion: The presence of dermatophilosis in Tamil Nadu was established from this study.ArticleItem Open Access Detection and Sequence Analysis of Accessory Gene Regulator Genes of Staphylococcus Pseudintermedius Isolates(Veterinary World, 2015-07) Chitra, M. Ananda; Jayanthy, C.; Nagarajan, B.; TANUVASBackground: Staphylococcus pseudintermedius (SP) is the major pathogenic species of dogs involved in a wide variety of skin and soft tissue infections. The accessory gene regulator (agr) locus of Staphylococcus aureus has been extensively studied, and it influences the expression of many virulence genes. It encodes a two-component signal transduction system that leads to down-regulation of surface proteins and up-regulation of secreted proteins during in vitro growth of S. aureus. The objective of this study was to detect and sequence analyzing the AgrA, B, and D of SP isolated from canine skin infections. Materials and Methods: In this study, we have isolated and identified SP from canine pyoderma and otitis cases by polymerase chain reaction (PCR) and confirmed by PCR-restriction fragment length polymorphism. Primers for SP agrA and agrBD genes were designed using online primer designing software and BLAST searched for its specificity. Amplification of the agr genes was carried out for 53 isolates of SP by PCR and sequencing of agrA, B, and D were carried out for five isolates and analyzed using DNAstar and Mega5.2 software. Results: A total of 53 (59%) SP isolates were obtained from 90 samples. 15 isolates (28%) were confirmed to be methicillinresistant SP (MRSP) with the detection of the mecA gene. Accessory gene regulator A, B, and D genes were detected in all the SP isolates. Complete nucleotide sequences of the above three genes for five isolates were submitted to GenBank, and their accession numbers are from KJ133557 to KJ133571. AgrA amino acid sequence analysis showed that it is mainly made of alpha-helices and is hydrophilic in nature. AgrB is a transmembrane protein, and AgrD encodes the precursor of the autoinducing peptide (AIP). Sequencing of the agrD gene revealed that the 5 canine SP strains tested could be divided into three Agr specificity groups (RIPTSTGFF, KIPTSTGFF, and RIPISTGFF) based on the putative AIP produced by each strain. The AIP of SP contains serine and produce lactone ring structured AIP. Conclusion: Presence of AgrA, B, and D in all SP isolates implies the importance of this regulatory system in the virulence genes expression of the SP bacteria. SP isolates can be typed based on the AgrD auto-inducible protein sequences as it is being carried out for typing of S. aureus isolates. However, further studies are required to elucidate the mechanism of controlling of virulence genes by agr gene locus in the pathogenesis of soft tissue infection by SP.ThesisItem Open Access Effect Of Nanomineral Supplementation In TANUVAS Smart Mineral Mixture On The Performance Of Lambs(Tamil Nadu Veterinary and Animal Sciences University, 2014) Ramesh, J.; TANUVAS; Valli, C.; Balakrishnan, V.; Raj, G. Dhinakar; Chitra, M. AnandaA research was conducted with the objective of exploring the scope of incorporating nanoparticle sources for calcium, phosphorus and copper in area specific mineral mixture (TANUVAS-SMART-Type III mineral mixture) and equating the proportion of nanoparticle to coarse particle sources for calcium, phosphorus and copper to be supplemented to lambs. The particle size and zeta potential of nano form of hydroxy apatite (44.20 nm, -28mV) and copper (43.50 nm, - 25mV) were produced by wet chemical / electrolytic method, leading to lower yield of hydroxyl apatite (1.25 g/hour) and copper (0.625g/hour) production. Hence physical method using ball mill was used for production of nano form of dicalcium phosphate with particle size and zeta potential of 46.60 nm, -26 mV and copper sulphate with 44.87nm, -20.5mV respectively. Yield for dicalcium phosphate and copper sulphate respectively was 25g/hour and100g/hour. Cytotoxicity assay of the nano form of dicalcium phosphate and copper sulphate carried out in African monkey kidney cells (Vero cell line) revealed that addition of both nano forms of dicalcium phosphate and copper sulphate up to 10 percent did not cause any cell inhibition and was considered safe at this level. The bioavailability of nano forms of dicalcium phosphate and copper sulphate was done using laying hens (Forstgate strain) in peak production (37 to 40 weeks) as animal model. Factorial design of 3 (0, 50 and 25 nano form of dicalcium phosphate) X 3 (0, 50 and 25 nanoform copper sulphate) was carried out with 6 birds in each treatment. The basal feed fed to birds of all treatments were same except for mineral supplementation. The control group had coarse forms of di calcium phosphate, calcite and copper sulphate supplying 100 % of requirement. Nano form of calcium phosphate at levels of 50 % and 25 % replaced dicalcium phosphate and calcite. Thus 50 and 25 % nano form of di calcium phosphate supplementation had 50 and 75 % less di calcium phosphate as compared to control. Similarly, copper sulphate was replaced by nano form of copper sulphate at 50 % and 25 %. Thus groups fed 50 and 25 % nano form of copper sulphate had 50 and 75 % less copper sulphate. In spite of reduced intake of calcium, phosphorus and copper nano form of minerals did not have a negative impact on body weight, hen day egg production, egg mass, and egg shell quality. The 50% nano form of dicalcium phosphate and 25% nano form copper sulphate supplemented group of birds had significantly lowest (p<0.05) feed intake, which reflected in improved feed efficiency. In spite of reduced calcium and phosphorus, the total ash or calcium or phosphorus of tibia remained un affected. The per cent calcium and phosphorus retained in tibia was significantly (p<0.05) highest in 25 percent nano form of di calcium phosphate and 50% nano form of copper sulphate, implicating a better bioavailability. The per cent copper retention was inversely proportional to the inclusion level of nano form of copper sulphate as evident from the significant (p< 0.05) increase in the per cent retention of copper in liver with decrease in the level of inclusion. Significant difference (p<0.05) in egg weight and specific gravity was altered due to nano minerals. Reduction in nano form of calcium, phosphorus and copper intake had no adverse effect on egg shell quality. The scope for further reduction in the inclusion level of these two minerals in the diet does exist. A Validation study on growing Sandyno lambs supplemented with TANUVAS SMART (Type III) mineral mixture Vs nano form of dicalcium phosphate at 50% and nano form of copper sulphate at 25 % incorporated TANUVAS SMART (Type III) mineral mixture confirmed the earlier finding by exhibiting no significant variations between treatments in growth rate, feed conversion ratio, tibial retention of calcium and phosphorus, liver retention of copper, serum calcium, phosphorus, copper, ceruloplasmin concentration, superoxide dismutase activity, slaughter characteristics, wool yield and quality. However the retention of calcium in tibia was improved to tune of 61.61 % , phosphorus retention by 25.77 per cent and copper retention in liver by 96.31 in nanoform minerals supplemented animals. Species, specific variation existed in nano form of mineral supplementation viz feed intake significantly reduced in layers, but not in lambs. Serum copper and tibial copper levels were influenced by nano form of dicalcium phosphate in layers but not in lambs, higher bioavailability with regard to copper in layers compared to lambs. Nano form of copper sulphate has better anthelmintic effect compared to its coarse counterpart, which could be probed further.ArticleItem Open Access Genome Sequencing and Comparative Genomics of Indian Isolates of Brucella melitensis(2021) Karthik, K.; Anbazhagan, S.; Thomas, P.; Chitra, M. Ananda; Senthilkumar, T.M.A.; Sridhar, R.; Raj, G. Dhinakar; TANUVASBrucella melitensis causes small ruminant brucellosis and a zoonotic pathogen prevalent worldwide. Whole genome phylogeny of all available B. melitensis genomes (n = 355) revealed that all Indian isolates (n = 16) clustered in the East Mediterranean lineage except the ADMAS-GI strain. Pangenome analysis indicated the presence of limited accessory genomes with few clades showing specific gene presence/absence pattern. A total of 43 virulence genes were predicted in all the Indian strains of B. melitensis except 2007BM-1 (ricA and wbkA are absent). Multilocus sequence typing (MLST) analysis indicated all except one Indian strain (ADMAS-GI) falling into sequence type (ST 8). In comparison with MLST, core genome phylogeny indicated two major clusters (>70% bootstrap support values) among Indian strains. Clusters with <70% bootstrap support values represent strains with diverse evolutionary origins present among animal and human hosts. Genetic relatedness among animal (sheep and goats) and human strains with 100% bootstrap values shows its zoonotic transfer potentiality. SNP-based analysis indicated similar clustering to that of core genome phylogeny. Among the Indian strains, the highest number of unique SNPs (112 SNPs) were shared by a node that involved three strains from Tamil Nadu. The node SNPs involved several peptidase genes like U32, M16 inactive domain protein, clp protease family protein, and M23 family protein and mostly represented non-synonymous (NS) substitutions. Vaccination has been followed in several parts of the world to prevent small ruminant brucellosis but not in India. Comparison of Indian strains with vaccine strains showed that M5 is genetically closer to most of the Indian strains than Rev.1 strain. The presence of most of the virulence genes among all Indian strains and conserved core genome compositions suggest the use of any circulating strain/genotypes for the development of a vaccine candidate for small ruminant brucellosis in India.ArticleItem Open Access Infectious Bovine Corneal Ulceration Associated with Methicillin Resistant Staphylococcus Aureus in a Dairy Cow - A Case Report(Indian Veterinary Journal, 2015-07) Ponnusamy, P.; Chitra, M. Ananda; Kumar, M. Ranjith; Ramesh, A.; TANUVASA 2 year old female Jersey cross bred diary cattle was presented to the Teaching Veterinary Clinical Complex, Veterinary College and Research Institute, Orathanadu, Thanjavur Dt, Tamil Nadu with history of bilateral corneal ulceration, lymph node enlargement and bruxism. Samples were taken from affected eyes using a sterile swab for bacterial isolation and identification. Staphylococcus aureus was isolated and identified and it was found to be most sensitive to Tetracycline, Enrofloxacin, Gentamicin and Amikacin and resistant to penicillin, ampicillin and methicillin. Animal was treated with gentamicin systematically and locally and completely recovered with restoration of vision in 5 days of treatment duration.ArticleItem Open Access Multiplex Pcr To Detect Brucella And Leptospira Species In Spiked Milk Samples(TANUVAS, Chennai, 2018-03) Priya, R. Manju; Chitra, M. Ananda; TANUVASBrucellosis and leptospirosis are zoonotic diseases and cause much economic losses in livestock by causing abortion, stillbirth and infertility. Both organisms are excreted in milk and thus increasing the risk of infecting other animals and human. Early detection of organisms is desirable for effective treatment and control of diseases. In this study, multiplex PCR was attempted to detect Brucella and Leptospira species in spiked milk samples.OtherItem Open Access Peste Des Petits Ruminants Outbreak in Barbari Goats - A Case Study(TANUVAS, 2006-06) Anandkumar, C. Theophilus; Brindha, K.; Chitra, M. Ananda; Ravikumar, G.; Chandran, N. Daniel Joy; Koteeswaran, A.ArticleItem Open Access Rapid Detection of Staphylococcus aureus Genomic DNA Using Peptide Nucleic Acid and Gold Nanoparticles(Council of the National Academy of Sciences, 2016-10) Chitra, M. Ananda; TANUVASStaphylococcus aureus is a Gram-positive bacterium and is known to affect almost all mammalian species. This organism causes a multitude of cutaneous and systemic human diseases and is the main etiological agent in causing bovine mastitis causing heavy economic loss to dairy industry. Microbiological detection of S. aureus is time consuming and molecular diagnostic technique requires skilled personnel and costly equipment. Peptide nucleic acids (PNA) are DNA analogues with charged neutral polyamide backbone. Free PNA induces aggregation of citrate capped colloidal gold nanoparticles. Using this property of PNA, rapid, simple, and an easy method of detecting S. aureus genomics was developed in the present study. PNA concentration of 1 lM induced clear colour change of gold nanoparticles from brick red to blue colour. Visual detection limit of complementary target DNA inhibiting PNA induced agglomeration of gold nanoparticles was 0.25 lM whereas, spectral detection limit was even at lower concentration of 0.1 lM. PNA induced aggregation was gradually reduced with increasing concentration of non-complementary DNA and concentration of non-complementary DNA of 2.5 times more than PNA concentration was able to prevent the PNA induced aggregation of gold nanoparticles. Sensitivity detection limit of this colorimetric assay in detecting genomic DNA of S. aureus was 106 cells visually and 104 cells spectrophotometrically. The test was performed with 20 field isolates of staphylococcal species. Out of 20 isolates, 16 were identified as S. aureus specifically. This assay was robust and had the advantage of being simple, fast and sensitive.ArticleItem Open Access Virulence Genes Detection and Antimicrobial Susceptibility of Staphylococcus pseudintermedius Isolates from Canine Skin Infection in Chennai, India(Council of the National Academy of Sciences, 2018-01) Chitra, M. Ananda; Jayanthy, C.; Nagarajan, B.; TANUVASStaphylococcus pseudintermedius (SP) is the major pathogen incriminated in the skin infections of dog. Identification of SP requires molecular methods. The incidence of methicillin resistant SP (MRSP) is increasing worldwide and it is a growing concern in treating pet animals. The prevalence of SP and MRSP from skin infections of dog in India has not been studied previously. Hence, the present study was aimed to isolate SP from common skin infections of dog in Chennai, India and to characterize these isolates. A total of 53 SP organisms were isolated from 91 samples of skin infection accounting for 59 % of isolation rate. Labrador was a major breed from which isolation was made. Panton–Valentine leucotoxin (Luk-I) and S. intermedius exfoliative toxin (siet) genes were detected in all SP isolates but staphylococcal protein A homologue (spsQ) gene was detected only in 36 % of the SP isolates. Out of 53 isolates, 17 % were found to be strong and 19 % to be moderate producers of biofilm and 28 % were classified as MRSP due to possession of the mecA gene. Most isolates were sensitive to tetracycline and ciprofloxacin and least sensitive to erythromycin and trimethoprim/sulphamethaxazole. The authors first time reported the isolation of MRSP, characterization of SP isolates by detecting virulence genes, biofilm forming ability and susceptibility to antimicrobials in Chennai, India.Book chapterItem Open Access கறவை மாட்டில் மெத்திசிலின் எதிர்ப்பு ஸ்டாபிலோகாக்கஸ் ஆரியஸினால் மாட்டின் விழிவெண்படல புண் தொற்று(Veelan ariviyal tamil iyakkam, Newdelhi, 2015) Ponnusamy, P.; Chitra, M. Ananda; Kumar, M. Ranjith; Ramesh, A.ArticleItem Open Access நோகார்டியா ஓடிடிடிஸ்கேவியேரம் : வெள்ளாட்டில் நிணநீர்சுரப்பி அழற்சியை உண்டாக்கும் நோகார்டியா நுண்ணுயிரி - ஒரு ஆய்வு(Veelan ariviyal tamil iyakkam, Newdelhi, 2016) Chitra, M. Ananda; Ponnuswamy, P.; Kumar, M. Ranjith; Ronald, B. Samuel MasilamoniArticleItem Open Access மாட்டின் கருச்சிதைவிலிருந்து த்ருபெரல்லா பயோஜென்ஸ் தனிமைப்படுத்துதல் மற்றும் அடையாளப்படுத்துதல்(Veelan ariviyal tamil iyakkam, Newdelhi, 2016) Ponnusamy, P.; Chitra, M. Ananda; Kumar, M. Ranjith; Maniickam, R.; Ronald, B. Samuel MasilamoniBook chapterItem Open Access ஸ்டெஃபைலோகாக்கஸ் சூட்இன்டர்மீடியஸ் : விலங்குகளிடம் இருந்து மனிதர்களுக்கு பரவும் திறன் கொண்ட ஒரு பாக்டீரியா?(Veelan ariviyal tamil iyakkam, Newdelhi, 2015) Chitra, M. Ananda