30 results on '"S, Vinodkumar"'
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2. Multitudinous Potential of Trichoderma Species in Imparting Resistance Against F. oxysporum f. sp. cucumerinum and Meloidogyne incognita Disease Complex
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S. Vinodkumar, B. Sreenayana, S. Nakkeeran, K. Poornima, and P. Muthulakshmi
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0106 biological sciences ,0301 basic medicine ,Exudate ,Rhizosphere ,biology ,Chemistry ,Plant Science ,biology.organism_classification ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Horticulture ,030104 developmental biology ,Seed treatment ,Shoot ,Fusarium oxysporum ,medicine ,Meloidogyne incognita ,medicine.symptom ,Agronomy and Crop Science ,Gibberellic acid ,Mycelium ,010606 plant biology & botany - Abstract
Trichoderma spp. effectively inhibited mycelial growth of Fusarium oxysporum f. sp. cucumerinum F1, egg hatchability and juvenile mobility of M. incognita. Field emission scanning electron microscope (FESEM) studies revealed that Trichoderma koningiopsis TRI 41 effectively hyperparasitized and lysed the mycelium of F. oxysporum f. sp. cucumerinum F1, egg mass and individual eggs of root-knot nematode. Further, GC–MS profiling of the agar plugs, excised from the point of hyperparasitism by TRI 41, from the dual plate assay revealed a shift in the non-volatile organic compounds (NVOC) profile. In vitro, TRI 41 produced maximum indole acetic acid (IAA) (15.25 µg/ml) and gibberellic acid (GA) (10.40 µg/ml) in PDB. T. koningiopsis TRI 41 increased the root length (28.74 cm), shoot length (14.64 cm) and stem girth (1.76 cm) of cucumber seedlings to the maximum in vermicompost:soil:sand medium. Furthermore, TRI 41 influenced the root architecture of cucumber plants and altered the root exudate pattern in the rhizosphere of 35-day-old cucumber seedlings. Various non-volatile organic compounds with antifungal and antibacterial activity were detected in the rhizosphere. Under field conditions, seed treatment with the consortia of the isolates, including T. koningiopsis TRI 41, Trichoderma asperellum TRI 15 and Trichoderma asperelloides TNAU Tad 1 @ 1 ml/kg of seed (0.1%) applied as soil drenching (100 ml of gel formulation in 100 L of water over 1000 m2 area of polyhouse), indicated that the incidence of fungal nematode complex was reduced to 13.45% with 80.0 fruits/plant with a mean yield of 15.01 t/1000m2. For instance, the untreated control was reported with 41.32 percent disease incidence, 52.0 fruits/plant with a mean yield of 10.20 t/1000m2.
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- 2021
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3. Currency as a Large Scale Fomite for Transmitting Pathogenic Bacteria in Community and Utility of UV Light to Disinfect Currency
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K G Basavarajappa, Prajwal Shanker, C. S. VinodKumar, and Suneeta Kalasuramath
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Commerce ,Scale (ratio) ,Currency ,medicine ,Environmental science ,Pathogenic bacteria ,medicine.disease_cause - Published
- 2020
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4. Thrips diversity of cotton ecosystem and the role of parthenium pollen grains in the transmission of tobacco streak virus (TSV) infection in cotton
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S. Vinodkumar, V. G. Malathi, S. Nakkeeran, P. Renukadevi, and S Rageshwari
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Veterinary medicine ,Scirtothrips dorsalis ,biology ,Thrips ,Parthenium hysterophorus ,Environmental Science (miscellaneous) ,biology.organism_classification ,Agricultural and Biological Sciences (miscellaneous) ,Parthenium ,Scirtothrips ,Trianthema portulacastrum ,Original Article ,Weed ,Tobacco streak virus ,Biotechnology - Abstract
Survey in the cotton fields of Coimbatore and Erode districts confirmed the presence of three different thrips species including, Scirtothrips dorsalis, Scirtothrips oligochaetus, and Frankliniella occidentalis. Their identity was confirmed through morphometric analysis and molecular characterization. Tobacco streak virus (TSV) was detected in the leaves and pollen grains of both parthenium and cotton plants collected from infected cotton fields. The presence of TSV was confirmed through immuno-detection by direct antigen coating enzyme-linked immuno sorbent assay (DAC-ELISA). Further confirmation was accomplished by reverse transcriptase polymerase chain reaction (RT-PCR) using TSV coat protein-specific primers. Other than parthenium, weed plants in the cotton field such as Trianthema portulacastrum, Boerhavia diffusa, and Amaranthus sp. were also confirmed for TSV infection through RT-PCR. Parthenium hysterophorus plants acts as a silent carrier of TSV and they occasionally produced symptoms. Among all the randomly collected thrips samples, two pooled samples were detected positive for TSV through RT-PCR. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02967-6.
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- 2021
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5. Grain refinement of 24 karat gold (99.99 wt.% pure) and 22 karat gold (Au-5.8wt.%Cu-2.5wt.%Ag) by Au-6wt.%Ti grain refiner
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G. S. Vinodkumar and K. M. Saradesh
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Materials science ,Alloy ,Metallurgy ,Nucleation ,Intermetallic ,chemistry.chemical_element ,Recalescence ,engineering.material ,Grain size ,Inorganic Chemistry ,chemistry ,Aluminium ,Metallic materials ,engineering ,General Materials Science - Abstract
In this paper, the 24 karat (99.99 wt.% pure) and 22 karat gold (Au-5.8wt.%Cu-2.5wt.%Ag) were grain refined with Au-6wt.%Ti master alloy and the mechanism of grain refinement was studied. The Au-6wt.%Ti master alloy containing Au2Ti and Au4Ti intermetallic particles was added into 24 karat and 22 karat gold at various addition levels of Ti (0.1, 0.2 and 0.3 wt.%) for grain refinement. The intermetallic particles undergo peritectic reaction with liquid Au in sequence to nucleate α-Au solid. It is observed that both the 24 karat gold and 22 karat gold showed efficient grain refinement at the lowest addition level of Ti (0.1 wt.%). However, 22 karat showed better grain-refining efficiency than 24 karat at all addition level of Ti studied. The mechanism of grain refinement of gold in this study matches with the “Peritectic theory” and “Solute paradigm” proposed for the grain refinement of aluminium. It is also observed that increasing the master alloy addition level to 0.2 and 0.3 wt.% Ti coarsening in the grain size in both 24 karat and 22 karat, but significant in the case of 24 karat gold due to recalescence effect. The grain-refined 24 karat and 22 karat gold at 0.1 wt.% Ti showed improvement in the hardness in comparison to the un-grain refined one.
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- 2020
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6. Therapeutic efficacy of Gefitinib in advanced NSCLC patients
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S Mathanraj, Deepa Kameswari P, D Biswajith, and S Vinodkumar
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medicine.medical_specialty ,business.industry ,Pleural effusion ,medicine.disease ,Gastroenterology ,Rash ,respiratory tract diseases ,Pulmonology ,Gefitinib ,Internal medicine ,Mucositis ,medicine ,medicine.symptom ,Adverse effect ,business ,Lung cancer ,Progressive disease ,medicine.drug - Abstract
Introduction: Lung cancer uprises from the respiratory epithelium cells is divided into two broad categories; Non–small cell lung cancer (NSCLC) and Small cell lung cancer (SCLC), derived from cells exhibiting Neuro-endocrine characteristics which is highly malignant tumour. The current drug therapy of Gefitinib has little evidence for its efficacy and safety profile in Indian patients. Aim: The research was focused to assess the efficacy of Gefitinib in advanced Non-small cell lung cancer. Materials and Methods: It is a retrospective study, done during the study period January 2009 to June 2012, and the number of NSCLC patients was 25 cases. Results: Of the 25 cases, 13 (52%) were males and 12 (48%) were females. The factors affecting survival have been studied there was a significant difference in survival between male and female sex (males 7.2 months; females 10.9 months). NSCLC patients were also having pleural effusion in 15 (60%) patients; fluid was hemorrhagic in 13 cases and straw coloured in 2 cases. The mean ADA level was 18.3 IU (5-43) and the Cell count was predominantly lymphocytic. The pleural fluid cytology was positive for malignant cells in 9 cases (60%) and the pericardial effusion was present in 4 patients. Calculating the objective response rate, there was no patients with complete response, 3 (16, 7%) with partial response, 9 (50%) cases with Stable disease and 6 (33.2%) had progressive disease and the overall rate of survival was 10.9 months (range 8.2-13.6). The most common adverse effect observed was diarrhea reported in 5 cases (20%), followed by rash in 4 (16.7%) and mucositis in 4 (16.7%) of cases. Conclusion: From the current study, it’s likely that, its use may not rapidly move NSCLC from advanced late-stage disease to earlier and less-advanced stages, but it is observed as a well tolerated drug that shows significant survival advantage with minimal toxicity. Keywords: Gefitinib, Non–small cell lung cancer (NSCLC), EGFR.
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- 2019
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7. Study on the electrochemical behaviour of 22k gold (Au-5.8wt.%Cu-2.5wt.%Ag) and Ti containing 22k gold (Au-5.8wt.%Cu-2.0wt.%Ag-0.5wt.%Ti)
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Indrajit M. Patil, G. S. Vinodkumar, D. Sivaprahasam, Bhalchandra Kakade, and K. M. Saradesh
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Materials science ,Sodium ,Alloy ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Electrochemical corrosion ,0104 chemical sciences ,Anode ,Corrosion ,Inorganic Chemistry ,Precipitation hardening ,chemistry ,engineering ,General Materials Science ,0210 nano-technology ,Polarization (electrochemistry) ,Nuclear chemistry - Abstract
The electrochemical corrosion behaviour of 22k gold (Au-5.8wt.%Cu-2.5wt.%Ag) and Ti containing 22k (Ti-22k) gold (Au-5.8wt.%Cu-2.0wt.%Ag-0.5wt.%Ti) was studied. Elemental Ti was added as the quaternary element to 22k gold by replacing Ag, resulting in the formation of secondary phase precipitates during age hardening treatment, thereby improving the hardness of the alloy. Anodic polarization tests were conducted for both 22k and Ti-22k samples in their as-cast annealed, cold-rolled annealed and age-hardened conditions using 0.9% sodium chloride and 1% lactic acid as medium. The as-cast and annealed 22k samples showed better corrosion resistance in both corrosion media whereas the 22k samples in the cold-rolled, annealed condition and Ti-22k samples in the as-cast, annealed condition showed poor corrosion resistance. After age-hardening treatment, cold-rolled Ti-22k samples showed better corrosion resistance due to the formation of passive layer (of TiO2) on the surface. However, corrosion gets initiated in the age-hardened Ti-22k due to the breaking and decomposition of the passive layer (TiO2) at a potential > 1.3 V.
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- 2019
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8. Antifungal Potential of Plant Growth Promoting Bacillus Species Against Blossom Blight of Rose
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Thangavel Surya, S. Vinodkumar, and S. Nakkeeran
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0106 biological sciences ,0301 basic medicine ,Bacillus amyloliquefaciens ,biology ,fungi ,food and beverages ,Plant Science ,Bacillus subtilis ,Pentadecanoic acid ,biology.organism_classification ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Bacillomycin ,Horticulture ,030104 developmental biology ,chemistry ,Blight ,Surfactin ,Agronomy and Crop Science ,Gibberellic acid ,010606 plant biology & botany ,Botrytis cinerea - Abstract
Blossom blight caused by Botrytis cinerea is one among the most devastating diseases that cause complete post-harvest loss in flower crops. The present study focuses on the development of effective bioformulation towards suppression of blossom blight and plant growth promotion in rose. Bacillus amyloliquefaciens (VB2) and Bacillus subtilis (AP) effectively inhibited mycelial growth of B. cinerea in vitro. Genome screening of VB2 and AP revealed the presence of antimicrobial peptide genes including, ituD, ipa14, bacA, bacD, srfA, sfP, spaC, spaS responsible for the biosynthesis of antibiotics such as iturin, bacilysin, bacillomycin, surfactin and subtilin. Further, the presence of volatile antifungal compounds in the bacterial secretome was identified through gas chromatography–mass spectrometry (GC/MS) analysis. Upon treatment, AP accelerated the metabolite profile of the plants and a rise in peak area of antifungal compounds such as, pentadecanoic acid, n-hexadecanoic acid, octadecanoic acid (stearic acid) and tetradecanoic acid was observed. In vitro, VB2 produced maximum indole acetic acid (9.17 µg/ml) and gibberellic acid (8.20 µg/ml) in nutrient broth. Under field conditions, foliar spray of VB2 at 0.5% (5 ml/l), four times at weekly interval suppressed blossom blight incidence (64% reduction over control) and also promoted yield. Future research towards development of an effective bioformulation with extended shelf life will aid in the management of various fungal, bacterial and viral diseases in different crop plants.
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- 2019
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9. Flagellin and elongation factor of Bacillus velezensis (VB7) reprogramme the immune response in tomato towards the management of GBNV infection
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M Vanthana, S Nakkeeran, Malathi V G, P Renukadevi, S Vinodkumar, U Sivakumar, and A Suganthi
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Necrosis ,Solanum lycopersicum ,Tospovirus ,Virology ,Immunity ,Bacillus ,Peptide Elongation Factors ,Flagellin ,Plant Diseases - Abstract
The present study investigates the reprogramming of plant defense system, upon interaction with MAMP (Microbe Associated Molecular Pattern) gene products including, flagellin (Flg) and elongation factor (EF-Tu) of Bacillus velezensis (VB7) and groundnut bud necrosis virus (GBNV) in tomato (Shivam). The MAMP gene products induced the plant defense genes including, PAL, PPO, LOX, JAR, MYC2 and PDF 1.2. Secondary metabolites of Bacillus spp. at 1000 parts per million (ppm) concentration effectively reduced GBNV symptom expression in cowpea (CO7) up to 83.1 % compared to untreated, GBNV inoculated, control. The secondary metabolites from B. velezensis (VB7) and B. licheniformis (Soya 1) reduced GBNV symptoms in cowpea (CO7) up to 1.7 lesions/cm
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- 2022
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10. Diversity and antiviral potential of rhizospheric and endophytic Bacillus species and phyto-antiviral principles against tobacco streak virus in cotton
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S. Vinodkumar, S. Nakkeeran, Subbarayalu Mohankumar, and P. Renukadevi
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0301 basic medicine ,education.field_of_study ,Rhizosphere ,Ecology ,Inoculation ,Population ,food and beverages ,Biology ,biology.organism_classification ,Rhizobacteria ,Piperazinedione ,Microbiology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Cereus ,Animal Science and Zoology ,education ,Surfactin ,Agronomy and Crop Science ,Tobacco streak virus - Abstract
Plant growth promoting rhizobacteria arewidely exploited for the management of various fungal and bacterial diseases in plants. However, antiviral action of PGPR and their efficiency have been rarely investigated. In the present study, influential diversity of Bacillus species was related with tobacco streak virus (TSV) infection in cotton. The study revealed that, the population of B. subtilis, B. licheniformis and B. velezensis in rhizosphere of apparently healthy cotton plants were comparatively higher than TSV infected plants, indicating that they efficiently colonized the rhizosphere. Similarly, the population of the endophytic B. cereus and B. licheniformis were relatively higher in apparently healthy than TSV infected cotton plants. In vitro screening of rhizospheric, endophytic Bacillus species and phyto-antiviral principles revealed that rhizospheric B. amyloliquefaciens (VB7) and endophytic B. licheniformis (CoEH6) were effective in the suppression of TSV symptoms in indicator host (cowpea). The strain B. amyloliquefaciens (VB7) contained ten antimicrobial peptide genes responsible for the biosynthesis of antibiotics including, iturin, bacilysin, bacillomycin, surfactin, subtilin, and subtilosin. Moreover, the strain VB7 is reported to secrete pentadecenoic acid, heptadecenoic acid, octadecenoicacid, pyrrolo, piperazinedione and tetradecenoic acid, which would have together complemented in the antiviral activity. Upon simultaneous inoculation of the bacterium or phyto-antiviral principles with TSV in the indicator host plant, revealed that B. amyloliquefaciens (VB7) and M. jalapa were much effective and reduced the number of lesions up to 2.22/leaf and 3.00/leaf respectively compared with TSV inoculated control (25.28 lesions cm−2 area). Further, under field conditions, soil application and foliar spray of the B. amyloliquefaciens (VB7) resulted in 52 per cent reduction in TSV incidence. For reference TSV incidence in B. amyloliquefaciens (VB7) treated and untreated plots were 21.67 (PDI) and 45 (PDI) respectively. Moreover, B. amyloliquefaciens (VB7) improved seed cotton yield upto 149.45 g/plant compared to control (97.71 g/plant). Thus B. amyloliquefaciens (VB7) was exploited as an efficient antagonist for the management of TSV in cotton.
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- 2018
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11. Evaluation of Fuel-Clad Chemical Interaction in PFBR MOX test fuel pins
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V. Anandaraj, C. Padmaprabu, S. Vinodkumar, B. Purna Chandra Rao, V.V. Jayaraj, M. Padalakshmi, S. Thirunavukkarasu, C.N. Venkiteswaran, B.K. Ojha, R. Divakar, Ran Vijay Kumar, Jojo Joseph, and V. Karthik
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010302 applied physics ,Nuclear and High Energy Physics ,Materials science ,Fission ,Neutron imaging ,Nuclear engineering ,02 engineering and technology ,Chemical interaction ,021001 nanoscience & nanotechnology ,01 natural sciences ,Breeder (animal) ,Nuclear Energy and Engineering ,Gas pressure ,Life limiting ,Eddy-current testing ,0103 physical sciences ,General Materials Science ,0210 nano-technology ,MOX fuel - Abstract
Fuel Clad Chemical Interaction (FCCI) is one of the life limiting issues in the MOX fuel pins of fast breeder reactors. Clad wastage due to FCCI coupled with stress arising from fission gas pressure and Fuel Clad Mechanical Interaction (FCMI) due to fuel swelling can lead to fuel pin failure. Non-destructive evaluation (NDE) techniques such as Gamma Scanning, Eddy current testing and Neutron Radiography have been successfully used on MOX fuel pins of a test sub-assembly irradiated in Fast Breeder Test Reactor (FBTR) to a burn-up of 112 GW d/t to detect signatures of FCCI. The results obtained by the various NDE techniques have been correlated and verified through metallographic examination on fuel pin cross-sections. The measured clad wastage of 85 μm agrees well with a model developed for MOX fuel with high Pu content. The results of examinations have enabled validation of the model and given confidence to the designer that PFBR MOX fuel can safely attain the target burn-up of 100 GW d/t.
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- 2018
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12. Tobacco streak virus: an emerging threat to cotton cultivation in India
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S. Vinodkumar, S. Nakkeeran, V. G. Malathi, Gandhi Karthikeyan, Subbarayalu Mohankumar, P. Renukadevi, and P. Amala Balu
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0106 biological sciences ,0301 basic medicine ,Veterinary medicine ,biology ,Chenopodium ,business.industry ,Serological assay ,Plant Science ,Coat protein ,biology.organism_classification ,01 natural sciences ,Chenopodium quinoa ,language.human_language ,Biotechnology ,03 medical and health sciences ,030104 developmental biology ,Insect Science ,Tamil ,language ,Host plants ,business ,Tobacco streak virus ,Leaf wetness ,010606 plant biology & botany - Abstract
Tobacco streak virus (TSV), inciting cotton necrosis, exhibits multifarious symptoms. Common types of symptoms include, purplish brown, necrotic lesions in the leaves, squares, and petioles. Telangana (India) had the highest incidence of TSV (51.11 PDI - hybrid RCH659), among the surveyed locations including, Tamil Nadu, Andhra Pradesh, Telangana and Maharashtra states of India. Environmental factors greatly influenced the establishment of TSV in cotton. Minimum temperature (22.81 °C), relative humidity (81.42%), and leaf wetness (23.94 h) favoured maximum TSV incidence with a mean PDI of 30.68 at Annur, (Tamil Nadu, India). Serological assay through DAC-ELISA confirmed the presence of TSV in cotton samples expressing necrosis symptoms. Bioassay revealed that Chenopodium amaranticolor and Chenopodium quinoa are excellent indicator host plants with high virus titres. Further, molecular characterization revealed the conserved nature of the coat protein gene, among the TSV isolates infecting cotton in four different states (Tamil Nadu, Andhra Pradesh, Telangana, and Maharashtra).
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- 2017
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13. Trichoderma asperellum (NVTA2) as a potential antagonist for the management of stem rot in carnation under protected cultivation
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T Indumathi, S. Nakkeeran, and S. Vinodkumar
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0106 biological sciences ,0301 basic medicine ,Rhizosphere ,biology ,Dianthus ,Sclerotinia sclerotiorum ,food and beverages ,Carnation ,biology.organism_classification ,01 natural sciences ,Fungicide ,03 medical and health sciences ,Horticulture ,030104 developmental biology ,Insect Science ,Botany ,Shoot ,Stem rot ,Agronomy and Crop Science ,Mycelium ,010606 plant biology & botany - Abstract
In the present investigative study, fifty Trichoderma spp. (Persoon) were isolated from the rhizosphere of various crop plants. Their potential, as an antagonist was assessed against S. sclerotiorum (Lib.) de Bary , causing stem rot of carnation ( Dianthus caryophyllus L.). T. asperellum (NVTA2) was superior in inhibiting the growth and development of stem rot pathogen up to 53.7 per cent in vitro . Seven Trichoderma species with greatest antagonistic potential were identified up to species level through molecular characterization. They were identified as T. asperellum (NVTA1, NVTA2), T. harzianum (NVTH1, NVTH2), T. citrinoviride (NVTC1, NVTC2), and T. erinaceum (NVTE1). Effective strains were screened for the presence of cellobiohydrolase ( cbh1 ) and endochitinase ( ech42 ) genes through PCR. Among the seven strains, T. asperellum (NVTA2) alone had both genes. Crude metabolite extracted from T. asperellum (NVTA2), effectively inhibited the mycelial growth of S. sclerotiorum up to 374.4 mm 2 . GC/MS profiling of crude extract revealed the presence of antifungal compounds including aliphatic hydrocarbons, terpenes and fatty acids. Root dipping and soil application of talc formulations of the seven Trichoderma spp. revealed that T. asperellum (NVTA2) effectively suppressed disease incidence up to 11.8 (PDI-Percent Disease Incidence) compared to the control (37.9 PDI), resulting in approximately 69% reduction. More over NVTA2 also promoted plant growth that resulted in increase in shoot numbers (6.60/plant), stalk length (72.7 cm) and flower yield (205.9 numbers/m 2 ), which were comparatively greater than control.
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- 2017
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14. Characterization and management of Botrytis cinerea inciting blossom blight of carnation under protected cultivation
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S. Nakkeeran and S. Vinodkumar
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0106 biological sciences ,0301 basic medicine ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Carnation ,030108 mycology & parasitology ,Biology ,Toxicology ,biology.organism_classification ,01 natural sciences ,03 medical and health sciences ,Protected cultivation ,Botany ,Blight ,010606 plant biology & botany ,Botrytis cinerea - Published
- 2017
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15. Detection of Carbapenem Resistance Encoding Genes Among Gram Negative Bacteria from Urinary Tract Infection in Patients with Type 2 Diabetes Mellitus
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C S Vinodkumar and Ajay Kumar
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0301 basic medicine ,carbapenem resistance encoding genes ,Gram-negative bacteria ,biology ,type 2 diabetes mellitus ,business.industry ,Urinary system ,030106 microbiology ,Type 2 Diabetes Mellitus ,bacterial infections and mycoses ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Microbiology ,QR1-502 ,03 medical and health sciences ,Immunology ,Medicine ,In patient ,gram negative bacilli ,urinary tract infection ,business ,Gene ,Biotechnology ,Carbapenem resistance - Abstract
The emergence and spread of carbapenem-resistant Enterobacteriaceae (CRE) in urinary tract infection among diabetic patients have become an increasing concern for management and treatment of the patients. The aim of this study was to investigate the genotypic features of CRE strains isolated from urinary tract infection among type 2 diabetes mellitus patients. A total of 1560 diabetic patients were screened for suspected urinary tract infection. 277 Gram negative bacteria were identified by Phoenix 100 system (Becton-Dickinson, USA). These isolates were screened for their ability to produce carbapenemases by a disc diffusion test. A total of 45 CRE isolates were recovered from these Gram negative bacteria. Carbapenamase producing isolates were screened for blaSPM, blaNDM, blaIMP, blaVIM, and blaGIM genes. The PCR products were sequenced in an ABI 3500 DNA sequencer (Applied Biosystems, USA). blaIMP-1, blaIMP-8, blaNDM-1, blaNDM-2, and blaNDM-4 were the predominant genes seen among E.coli, Klebsiella pneumoniae, Citrobacter freundii, Acinetobacter baumannii and Proteus mirabilis. Colistin and Amikacin were the drug of choice and Colistin had the MIC value of < 1mg/l and for Amikacin 62% of isolates had MIC value of < 4mg/l. This rising trend of carbapenem resistance among Gram negative bacteria stresses the increasing importance of continuous surveillance system and stewardship of antibiotics as strategies in the overall management of diabetic patients with urinary tract infection.
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- 2017
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16. Induction of in planta resistance by flagellin (Flg) and elongation factor-TU (EF-Tu) of Bacillus amyloliquefaciens (VB7) against groundnut bud necrosis virus in tomato
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S. Nakkeeran, S. Vinodkumar, M. Vanthana, V. G. Malathi, and P. Renukadevi
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0301 basic medicine ,Bacillus amyloliquefaciens ,030106 microbiology ,Secondary Metabolism ,Peptide Elongation Factor Tu ,Rhizobacteria ,Microbiology ,Antiviral Agents ,Plant Viruses ,03 medical and health sciences ,Solanum lycopersicum ,Gene Expression Regulation, Plant ,Plant virus ,Plant defense against herbivory ,MAMP ,Plant Diseases ,Plant Proteins ,biology ,fungi ,food and beverages ,Agrobacterium tumefaciens ,biology.organism_classification ,Elongation factor ,030104 developmental biology ,Infectious Diseases ,biology.protein ,Flagellin - Abstract
Role of plant growth promoting rhizobacteria (PGPR) in growth promotion and induction of resistance against various plant pathogens have been extensively studied. However, MAMP (Microbe Associated Molecular Pattern) triggered immunity (MTI) against plant viruses are not well exploited. The present study enlightens the role of two MAMP genes including, flagellin (Flg) and elongation factor (EF-Tu) in the induction of plant defense against GBNV infecting tomato. Secondary metabolites of Bacillus amyloliquefaciens (VB7), effectively suppressed GBNV symptom expression up to 84% compared to untreated control in cowpea, the indicator host plant. Agrobacterium tumefaciens EHA105 clones expressing the MAMP genes were drenched in the root zone to assess the induction of resistance against GBNV in tomato. Treatment with A. tumefaciens EHA105 clones containing flagellin (Ag- Ba.Flg) and elongation factor-TU (Ag-Ba.EF-Tu) genes as soil drench and foliar spray, reduced virus titre,0.369 OD and 0.379 OD respectively as compared to control 1.249 OD. The disease severity was reduced up to 15% in Ag-Ba.Flg treated plants compared to 88.25% in inoculated control. Further there was an increased expression of defense associated genes including, MAPKK1, WRKY33BB, NPR1 and PR1.The present investigation clearly indicated the efficiency of MAMP genes in triggering defense mechanism in tomato against GBNV.
- Published
- 2019
17. Phenotypic and molecular characterization of chrysanthemum white rust pathogen Puccinia horiana (Henn) and the effect of liquid based formulation of Bacillus spp. for the management of chrysanthemum white rust under protected cultivation
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R. Dheepa, S. Nakkeeran, S. Vinodkumar, and P. Renukadevi
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0106 biological sciences ,0301 basic medicine ,Spots ,food and beverages ,Bacillus sp ,Ribosomal RNA ,Biology ,biology.organism_classification ,01 natural sciences ,Rust ,White (mutation) ,03 medical and health sciences ,Horticulture ,biology.plant_disease ,030104 developmental biology ,Insect Science ,Botany ,Puccinia horiana ,Agronomy and Crop Science ,Pathogen ,Bacteria ,010606 plant biology & botany - Abstract
Chrysanthemum varieties were surveyed for the incidence of white rust caused by P. horiana (Henn) in Salem and Nilgiris provinces in Tamil Nadu, India during 2013–2014. Among the different varieties, the variety saffin pink was highly susceptible to chrysanthemum white rust (CWR) with incidence ranging between 62.72% and 65.81%. Symptoms were visible 7–10 days after initial infection followed by the production of telia. Symptoms of CWR were characterized with the presence of pale-green to yellow white rust spots, (5 mm diameter), on the upper surface of the leaf. Centre of the spots turns brown and necrotic upon aging. On the corresponding lower surface, raised, buff or pinkish, waxy pustules (telia) were observed. Severely affected leaves wilt, droop and gradually dry up. Besides, white rust pathogen P. horiana was confirmed with species specific primers Ph-F1 and Ph-R1; Ph-F2 and Ph-R1, which yielded an amplicon size of approximately 240 bp and 340 bp corresponding to the region of the 18S-28S rRNA. Crude metabolites and extracellular antifungal compounds from B. subtilis (BS2) and B. amyloliquefaciens (BSC7) were analyzed for the presence of bioactive molecules of antifungal nature against P. horiana teliospores through GC–MS analysis. Bio-efficacy of antagonistic bacteria against CWR indicated that, foliar application of B. subtilis (BS2) and B. amyloliquefaciens (BSC7) at fortnightly intervals was most effective in reducing the incidence of white rust. Furthermore, it also increased plant height, marketable stems, and flower yield.
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- 2016
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18. Bioactive Molecules from Bacillus spp.: An Effective Tool for Plant Stress Management
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P. Renukadevi, S. Rajamanickam, S. Vinodkumar, Sudisha Jogaiah, and S. Nakkeeran
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biology ,fungi ,food and beverages ,Antimicrobial ,biology.organism_classification ,Plant disease ,Microbiology ,Crop ,chemistry.chemical_compound ,Quorum sensing ,Bacillus isolates ,chemistry ,Mode of action ,Surfactin ,Bacteria - Abstract
The beneficial microbes are used to manage the plant diseases for sustainable agriculture production, which are alternatives to chemical fertilizers and pesticides. A key parameter in the effective management of plant disease is to protect the crop before the establishment of pathogen in an infection court. Recently, Bacillus species have been well demonstrated for its effectiveness against plant diseases, since it is most common bacteria found to colonize plants easily. Bacillus sp. inhibits the growth of phytopathogens directly or indirectly, through competition of space and nutrients. In addition, a wide variety of secondary metabolites are produced by Bacillus species that shows their ability as biocontrol agents against various plant diseases. Many potent Bacillus spp. possess secondary metabolites, including the difficidin, polyketides, and bacillaene. The Bacillus isolates produce several antimicrobial lipopeptides genes including fengycin, iturin, bacillomycin D, and surfactin. The resultant products of these molecules have been reported to inhibit fungal and bacterial diseases in crops. The indirect mode of action includes promoting plant growth and stimulation of the defense mechanism that trigger the first line of defense. These microbes have been known to facilitate a diverse mechanisms like quorum sensing (QS) for plant signal interference, production of volatile organic compounds (VOCs), displaying antimicrobial activity and induction of systemic resistance, thereby promoting beneficial plant–microbe interactions. Besides, the endospore-forming ability of the bacteria enhances their survival capability under diverse environmental conditions. Lastly, the antibiotic production induced resistance and growth promotion action mediated by Bacillus spp. as an effective management tool for plant disease control, since it is durable and environment-friendly alternative for chemical-based plant disease management.
- Published
- 2019
- Full Text
- View/download PDF
19. Prevalence of Burn Wound Infections with Aerobic and Anaerobic Bacteria and their Antimicrobial Susceptibility Pattern at Tertiary Care Hospital
- Author
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C S VinodKumar
- Subjects
Burn injury ,medicine.medical_specialty ,Burn wound ,business.industry ,Antimicrobial susceptibility ,Tertiary care hospital ,Antimicrobial ,Surgery ,Bacterial colonization ,Internal medicine ,Medicine ,Anaerobic bacteria ,business ,Prospective cohort study - Abstract
Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care1. A prospective study was carried out in 30 burn patients admitted in Burn unit of S.S. Institute of Medical Sciences and Research Centre, Davangere, for over a period of four months to evaluate time-related changes in bacterial colonization and their sensitivity pattern. Methods: Periodic swabs were taken from the burn wound on Day 0, Day 7, Day 14 and Day 21 to see the changing pattern of organ- isms during hospital stay of patients by standard microbiological techniques and antimicrobial susceptibility testing was done as per CLSI guidelines. Results: In the present study burn injury was highest in the age group 20-30 yrs (42%). Female to male ratio was 1.4:1 Among the 120 samples, single organism was isolated in 64% samples and mixed organism in 26% and no growth in 12%. Among the single isolates A.baumannii was leading (28%) followed by Ps.aeruginosa (18%), K. pneumoniae (14%) and S.aureus (12%). Among mixed growth Ps.aeruginosa + A.baumanni (42%) and K.pneumoniae + Bacteriodes fragilis (36%) were leading combination of organism seen. There was time related changes in bacterial isolation from burn wound during hospital stay of patients. On admission 52% of the isolated organisms were S.aureus, only 18% of CoNS and 10% E. coli. These findings were gradually changing with time and on day 21 S.aureus were only 6% whereas A.baumannii was isolated in 28% and Ps.aeruginosa were isolated in 18%. Antimicrobial sensitivity test showed that Ps. aeruginosa and A.baumannii was highly resistant to antimicrobial agents. Conclusion: It is crucial for every burn institution to determine the specific pattern of a burn wound microbial colonization, the time- related changes in dominant flora, and the antimicrobial sensitivity profiles so that hospital stay can be shortened thereby improving overall infection related morbidity and mortality.
- Published
- 2012
- Full Text
- View/download PDF
20. Bacillus amyloliquefaciens (VB7) with Diverse Antimicrobial Peptide Genes:A Potential Antagonist for the Management of Fairy Ring Spot in Carnations
- Author
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S. Vinodkumar and S. Nakkeeran
- Subjects
0106 biological sciences ,chemistry.chemical_classification ,Multidisciplinary ,Bacillus amyloliquefaciens ,biology ,Antagonist ,Fairy ring ,Peptide ,04 agricultural and veterinary sciences ,Antimicrobial ,biology.organism_classification ,01 natural sciences ,040501 horticulture ,Microbiology ,chemistry ,0405 other agricultural sciences ,Gene ,010606 plant biology & botany - Published
- 2018
- Full Text
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21. Making a case for the use of Denver shunts in malignant ascites: A retrospective cohort study
- Author
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G. Shankar, S. Vinodkumar, W. Hugh, and O. Chinomso
- Subjects
medicine.medical_specialty ,business.industry ,General surgery ,education ,Retrospective cohort study ,General Medicine ,Surgery ,Denver shunts ,health services administration ,Ascites ,Medicine ,medicine.symptom ,business - Published
- 2016
- Full Text
- View/download PDF
22. Public transport: a large scale fomite of methicillin-resistant Staphylococcus aureus
- Author
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V Aditya Reddy, Satish A. Patil, Raghu . Kumar K. G, Sonika Bindu Prasad, C S Vinodkumar, K G Basavarajappa, Ankita Jha, and V L Jayasimha
- Subjects
Scale (ratio) ,business.industry ,Environmental health ,Medicine ,business ,medicine.disease_cause ,Methicillin-resistant Staphylococcus aureus - Abstract
Background: The role of public transport as reservoirs of antibiotic-resistant staphylococci was determined.Methods: 200 swabs were collected from 50 public buses (urban and rural) circulating in Davangere, Karnataka. Swabs collected were inoculated on Blood agar, Mannitol salt agar and MacConkey agar plates. After incubation for 24-48 hours, plates were examined for the growth of Staphylococcus aureus. Anti-microbial susceptibility test was performed using oxacillin 1ug disc to detect methicillin resistance as per CSLI guidelines.Results: Out of 40 Staphylococcus aureus isolated 35 isolates were resistant to more than two classes of antibiotics, hence multidrug resistant Staphylococcus aureus. Out of 35 MDR isolates, 18 were resistant to oxacillin and cefoxitin. Minimum inhibitory concentration test revealed that out of 35 MDR isolates, 18 isolates had MIC value of ≥ 4µg/ml.Conclusions: The recovery methicillin-resistant Staphylococcus aureus from public transport system implies a potential risk for transmission of these bacteria in community.
- Published
- 2017
- Full Text
- View/download PDF
23. Repercussion of biofilm and antibiotic resistance in ventilator associated pneumonia
- Author
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K G Raghu Kumar, K Niranjan, K.R. Shama Taj, Arun Kumar, C S Vinodkumar, Bikram Prasad, K G Basavarajappa, Satish S. Patil, N. K. Kalappanavar, and V L Jayasimha
- Subjects
medicine.medical_specialty ,Antibiotic resistance ,business.industry ,medicine ,Biofilm ,Ventilator-associated pneumonia ,Intensive care medicine ,medicine.disease ,business - Abstract
Background: Ventilator associated pneumonia contributes nearly half of all cases of hospital-acquired pneumonia. Drug resistance among ventilator associated pneumonia has obligation of device withdrawal in order to achieve clinical and microbiological cure. Aim of the study was to determine the relationship between antibiotic resistance of Endotracheal tube biofilm and pulmonary pathogens in ventilator-associated pneumonia.Methods: A descriptive analytical study of 100 clinically suspected VAP patients was done. Patients were divided into group-I and Group-II based on intubation duration for 1-5 days and 6-10 days respectively. Endotracheal aspirate (ETA) was collected from clinically diagnosed cases and processed as per standard microbiological techniques. Bacterial counts ≥106 CFU/ml for quantitative cultures was considered significant. Biofilm production was detected by tissue culture plate, tube method and Congo red method. Multi-variant analysis was done to find out the association of the various factors.Results: Klebsiella pneumoniae was the predominant bacteria isolated followed by Acinetobacter baumannii. 45% of Gram negative bacteria were β lactamase producers. In Biofilm production by tissue culture method, 72% of the isolates showed either strong or moderate biofilm formation. Multivariate analysis revealed that bacteria isolated from VAP occurring after 5 days of mechanical ventilation among prior antibiotic-treated patients were resistant to all the antibiotics tested.Conclusions: Bacterial aetiology, biofilm formation and drug resistance has ramification on outcome of ventilator associated pneumonia. Hence, advised that it is crucial to remove ET tube in regular interval to prevent biofilm formation and sequential cultures to obtain the microbiological information which enables better patient care.
- Published
- 2017
- Full Text
- View/download PDF
24. Carbon particles in airway macrophage as a surrogate marker in the early detection of lung diseases
- Author
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N K, Kalappanavar, C S, Vinodkumar, C, Gouli, D, Sanjay, K, Nagendra, K G, Basavarajappa, and R, Patil
- Subjects
Male ,Air Pollutants ,Chi-Square Distribution ,Adolescent ,Vital Capacity ,India ,Maximal Midexpiratory Flow Rate ,Environmental Exposure ,Carbon ,Early Diagnosis ,Spirometry ,Forced Expiratory Volume ,Macrophages, Alveolar ,Prevalence ,Humans ,Female ,Particulate Matter ,Lung Diseases, Obstructive ,Child ,Respiratory Tract Infections ,Biomarkers - Abstract
It has been shown that inhalation of carbonaceous particulate matter may impair lung function in children.Using the carbon content of airway macrophages as a marker of individual exposure to particulate matter derived from fossil fuel, we sought direct evidence for this association.300 children from puffed rice industrial areas and 300 children from population living in green zone were selected randomly. Airway macrophages were obtained from healthy children through sputum induction, and the grading of ultrafine carbon particles in airway macrophages was measured. Pulmonary function was also measured by spirometry.Pulmonary function tests showed that in industrial area 42.6% and 20.3% of children had moderate obstructive airway disease and restrictive airway disease, respectively. In the green zone area, 7% of children had obstructive airway disease and 6% had restrictive airway disease. Evaluation of airway macrophages for ultrafine carbon particles revealed that in industrial area there were ultrafine carbon particles of grade 2 in 23% of subjects and grade 3 in 8.33% of individuals with obstructive airway disease. In the green zone area, the rates were 1.67% and 0.7%, respectively.The study provides a first evidence of the strong association between air pollution and development of airway diseases. Carbon particles in the sputum can be used as a marker for air pollution.
- Published
- 2011
25. Utility of lytic bacteriophage in the treatment of multidrug-resistant Pseudomonas aeruginosa septicemia in mice
- Author
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C S, Vinodkumar, Suneeta, Kalsurmath, and Y F, Neelagund
- Subjects
Male ,Mice ,Mice, Inbred BALB C ,Drug Resistance, Multiple, Bacterial ,Sepsis ,Pseudomonas aeruginosa ,Animals ,Pseudomonas Infections ,Pseudomonas Phages ,Injections, Intraperitoneal - Abstract
Drug resistance is the major cause of increase in morbidity and mortality in neonates. One thousand six hundred forty-seven suspected septicemic neonates were subjected for microbiological analysis over a period of 5 years. Forty-two P. aeruginosa were isolated and the antibiogram revealed that 28 P. aeruginosa were resistant to almost all the common drugs used (multidrug-resistant). The emergence of antibiotic-resistant bacterial strains is one of the most critical problems of modern medicine. As a result, a novel and most effective approaches for treating infection caused by multidrug-resistant bacteria are urgently required. In this context, one intriguing approach is to use bacteriophages (viruses that kill bacteria) in the treatment of infection caused by drug-resistant bacteria. In the present study, the utility of lytic bacteriophages to rescue septicemic mice with multidrug-resistant (MDR) P. aeruginosa infection was evaluated. MDR P. aeruginosa was used to induce septicemia in mice by intraperitoneal (i.p.) injection of 10(7) CFU. The resulting bacteremia was fatal within 48 hrs. The phage strain used in this study had lytic activity against a wide range of clinical isolates of MDR P. aeruginosa. A single i.p. injection of 3 x 10(9) PFU of the phage strain, administered 45 min after the bacterial challenge, was sufficient to rescue 100% of the animals. Even when treatment was delayed to the point where all animals were moribund, approximately 50% of them were rescued by a single injection of this phage preparation. The ability of this phage to rescue septicemic mice was demonstrated to be due to the functional capabilities of the phage and not to a nonspecific immune effect. The rescue of septicemic mice could be affected only by phage strains able to grow in vitro on the bacterial host used to infect the animals and when such strains are heat-inactivated, they lose their ability to rescue the infected mice. Multidrug-resistant bacteria have opened a second window for phage therapy. It would seem timely to begin to look afresh at this approach. A scientific methodology can make phage therapy as a stand-alone therapy for infections that are fully resistant to antibiotics.
- Published
- 2008
26. Emergence of extended spectrum beta lactamase mediated resistance in neonatal septicemia
- Author
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C S, Vinodkumar and Y F, Neelagund
- Subjects
Drug Resistance, Bacterial ,Gram-Negative Bacteria ,Infant, Newborn ,Humans ,Bacteremia ,Microbial Sensitivity Tests ,Gram-Negative Bacterial Infections ,beta-Lactam Resistance ,beta-Lactamases ,Anti-Bacterial Agents - Abstract
This study was carried out in microbiology department of Gulbarga university, Gulbarga to find out the frequency of extended spectrum beta lactamase (ESbL) producing gram-negative bacilli isolated from neonatal septicemic cases. This study was carried out from Oct 2001 to June 2004. A total of 471 consecutive Gram-negative bacilli were recovered during the study period from blood samples. Extended spectrum beta lactamase detection in gram-negative isolates was carried out by double disk synergistic method on Mueller Hinton agar. A susceptibility disk containing amoxicillin-clavulanate was placed as the inhibitor of beta lactamase in the center of the plate, and cefotaxime, ceftazidime, ceftriaxone and aztreonam disks were placed 30 mm (center to center) from the amoxicillin-clavulanate disk. Enhancement of the zone of inhibition of the oxyimino-lactam caused by the synergy of the clavulanate in the amoxicillin-clavulanate disk was considered as evidence of ESbL production. Escherichia coli ATCC 25922 and K. pneumoniae ATCC 700603 were used as control strains. The frequency of ESbL producing gram-negative bacilli among the neonatal septicemic cases was 22.7%.
- Published
- 2006
27. Bacteriophage in the treatment of experimental septicemic mice from a clinical isolate of multidrug resistant Klebsiella pneumoniae
- Author
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C S, Vinodkumar, Y F, Neelagund, and Suneeta, Kalsurmath
- Subjects
Male ,Klebsiella pneumoniae ,Mice ,Mice, Inbred BALB C ,Drug Resistance, Multiple, Bacterial ,Animals ,Bacteremia ,Bacteriophages ,Klebsiella Infections - Abstract
Drug resistance is the major cause of increase in morbidity and mortality in neonates. The emergence of antibiotic-resistant bacterial strains requires the exploration of alternative antibacterial therapies and the concern that human kind in re-entering the 'pre-antibiotic era' has become very real and the development of alternative anti-infection modalities has become one of the highest priorities of modern medicine and biotechnology. This has spurred biomedical researchers to expand their efforts to identify new technologies and products that employ novel mechanism of action against the "super-bugs". One of such alternatives stems up from an old idea is the bacteriophage therapy, which led our group to study the ability of bacterial viruses (bacteriophages or phages) to rescue septicemic mice with multidrug resistant (MDR) Klebsiella pneumoniae isolated from neonatal septicemia. The phage strain used in this study had lytic activity against a wide range of clinical isolates of MDR Klebsiella pneumoniae. One of these MDR Klebsiella strain was used to induce septicemia in mice by intraperitoneal (i.p.) injection of 10(9) CFU. The resulting bacteremia was fatal within 48 h. A single i.p. injection of 3x10(8) PFU of the phage strain administered 45 min after the bacterial challenge, was sufficient to rescue 100% of the animals. Even when treatment was delayed to the point where all animals were moribund, approximately 50% of them were rescued by a single injection of this phage preparation. The ability of this phage to rescue septicemic mice was demonstrated to be due to the functional capabilities of the phage and not to a nonspecific immune effect. The rescue of septicemic mice could be affected only by phage strains able to grow in vitro on the bacterial host used to infect the animals and when such strains are heat inactivated they lose their ability to rescue the infected mice.
- Published
- 2006
28. Seroprevalence of HBV among people visiting barbers at Gulbarga
- Author
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C S, VinodKumar, H, Anandkumar, Indu, Kapur, and A K, Ratna
- Subjects
Adult ,Hepatitis B virus ,Hepatitis B Surface Antigens ,Adolescent ,Seroepidemiologic Studies ,Carrier State ,Allied Health Personnel ,Humans ,India ,Middle Aged ,Child ,Barbering - Published
- 2004
29. Ofloxacin induced arthropathy in patients with multi-drug resistance tuberculosis
- Author
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A, Tumbanatham and S, Vinodkumar
- Subjects
Adult ,Ofloxacin ,Arthritis ,Tuberculosis, Multidrug-Resistant ,Antitubercular Agents ,Humans ,India ,Drug Interactions ,Drug Therapy, Combination ,Female ,Tuberculosis, Lymph Node - Abstract
Some of the 4-fluroquinolones have been reported to induce arthropathy, but so far there are no case reports of arthropathy due to ofloxacin. Two cases of ofloxacin induced arthropathy in multi-drug resistance (MDR) tuberculosis are reported and possible drug interaction with other anti-tubercular drugs is discussed.
- Published
- 2001
30. Utility of lytic bacteriophage in the treatment of multidrug-resistant Pseudomonas aeruginosa septicemia in mice
- Author
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C S Vinodkumar, Suneeta Kalsurmath, and Y F Neelagund
- Subjects
Microbiology (medical) ,Modern medicine ,Phage therapy ,biology ,medicine.drug_class ,medicine.medical_treatment ,Antibiotics ,General Medicine ,Drug resistance ,medicine.disease ,biology.organism_classification ,Virology ,Pathology and Forensic Medicine ,Microbiology ,Multiple drug resistance ,Bacteriophage ,Lytic cycle ,Bacteremia ,medicine - Abstract
Drug resistance is the major cause of increase in morbidity and mortality in neonates. One thousand six hundred forty-seven suspected septicemic neonates were subjected for microbiological analysis over a period of 5 years. Forty-two P. aeruginosa were isolated and the antibiogram revealed that 28 P. aeruginosa were resistant to almost all the common drugs used (multidrug-resistant). The emergence of antibiotic-resistant bacterial strains is one of the most critical problems of modern medicine. As a result, a novel and most effective approaches for treating infection caused by multidrug-resistant bacteria are urgently required. In this context, one intriguing approach is to use bacteriophages (viruses that kill bacteria) in the treatment of infection caused by drug-resistant bacteria. In the present study, the utility of lytic bacteriophages to rescue septicemic mice with multidrug-resistant (MDR) P. aeruginosa infection was evaluated. MDR P. aeruginosa was used to induce septicemia in mice by intraperitoneal (i.p.) injection of 10 7 CFU. The resulting bacteremia was fatal within 48 hrs. The phage strain used in this study had lytic activity against a wide range of clinical isolates of MDR P. aeruginosa. A single i.p. injection of 3 × 10 9 PFU of the phage strain, administered 45 min after the bacterial challenge, was sufficient to rescue 100% of the animals. Even when treatment was delayed to the point where all animals were moribund, approximately 50% of them were rescued by a single injection of this phage preparation. The ability of this phage to rescue septicemic mice was demonstrated to be due to the functional capabilities of the phage and not to a nonspecific immune effect. The rescue of septicemic mice could be affected only by phage strains able to grow in vitro on the bacterial host used to infect the animals and when such strains are heat-inactivated, they lose their ability to rescue the infected mice. Multidrug-resistant bacteria have opened a second window for phage therapy. It would seem timely to begin to look afresh at this approach. A scientific methodology can make phage therapy as a stand-alone therapy for infections that are fully resistant to antibiotics.
- Published
- 2008
- Full Text
- View/download PDF
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