In Vitro Streptococcus pneumoniae Biofilm Formation and In Vivo Middle Ear Mucosal Biofilm in a Rat Model of Acute Otitis Induced by S. pneumoniae

yadav mukesh kumar,채성원,송재준 대한이비인후과학회 2012 Clinical and Experimental Otorhinolaryngology Vol.5 No.3

Objectives. Streptococcus pneumoniae is one of the most common pathogens of otitis media (OM) that exists in biofilm,which enhances the resistance of bacteria against antibiotic killing and diagnosis, compared to the free-floating (planktonic)form. This study evaluated biofilm formation by S. pneumoniae on an abiotic surface and in the middle ear cavity in a rat model of OM. Methods. In vitro biofilm formation was evaluated by inoculation of a 1:100 diluted S. pneumoniae cell suspension in a 96-well microplate. Adherent cells were quantified spectrophotometrically following staining with crystal violet by measurement of optical density at 570 nm. The ultrastructure of pneumococcal biofilm was assessed by scanning electron microscopy (SEM). For in vitro biofilm study, S. pneumoniae cell suspensions containing 1×107 colony forming units were injected through transtympanic membrane into the middle ear cavity of Sprague Dawley rats. The ultrastructure of middle ear mucus was observed by SEM 1 and 2 weeks post-inoculation. Results. The in vitro study revealed robust biofilm formation by S. pneumoniae after 12-18 hours of incubation in high glucose medium, independent of exogenously supplied competence stimulating peptide and medium replacement. Adherent cells formed three-dimensional structures approximately 20-30 μm thick. The in vivo study revealed that ciliated epithelium was relatively resistant to biofilm formation and that biofilm formation occurred mainly on non-ciliated epithelium of the middle ear cavity. One week after inoculation, biofilm formation was high in 50% of the treated rats and low in 25% of the rats. After 2 weeks, biofilm formation was high and low in 25% and 37.5% of rats, respectively. Conclusion. The results imply that glucose level is important for the S. pneumoniae biofilm formation and S. pneumoniae biofilm formation may play important role in the pathophysiology of OM

Morphological and Phylogenetic Analysis of a New Record of Paraconiothyrium kelleni from Soil in Korea

Mukesh Kumar Yadav,Kallol Das,류정주,Seong-Keun Lim,Jin-Sil Choi,Lee Seung-Yeol,Hee-Young Jung 한국균학회 2023 韓國菌學會誌 Vol.51 No.2

A fungal strain designated KNUF-21-66Q1 was isolated from soil in Chungcheongbuk Province, Korea. Moderate growth of colonies was observed on potato dextrose agar, oatmeal agar (OA), malt extract agar, and cornmeal agar media at 25℃, and the detailed morphology was examined on OA medium. The colonies on OA medium were flat, had entire margin, hyaline, and yellow concentric rings in 3-4 weeks. Conidiomata were pycnidial, solitary or clustered, globose to subglobose, black-brown, and 300-500 μm in diameter. Conidiogenous cells were smooth, hyaline, globose to ampulliform, and 6.0- 9.0×3.0-6.0 μm in size (n=15). Conidia were hyaline to pale brown, slightly golden, obovoid to slightly ellipsoidal, smooth, guttulate, and 3.0-4.7×2.1-3.3 μm in size (n=100). The strain was confirmed based on phylogenetic analysis using internal transcribed spacer regions, the partial 28S rDNA of large subunit, and β-tubulin gene sequences. The morphological observations and phylogenetic analysis revealed that the strain KNUF-21-66Q1 was similar to the previously described Paraconiothyrium kelleni. To our knowledge, this is the first report of P. kelleni in Korea.

Biological and Medicinal Properties of Grapes and Their Bioactive Constituents: An Update

Mukesh Yadav,Shalini Jain,Aarti Bhardwaj,Ravinder Nagpal,Monica Puniya,Radha Tomar,Vinod Singh,Om Parkash,G.B.K.S. Prasad,Francesco Marotta,Hariom Yadav 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.3

The grape is one of the most valued conventional fruits, worldwide. Although most of the parts of the grapevine are useful, primarily, the grape is considered as a source of unique natural products not only for the development of valuable medicines against a number of diseases, but also for manufacturing various industrial products. Over the last few decades, apart from the chemistry of grape compounds, considerable progress has been made towards exploring the biological activities of various grape-derived constituents. Today, it is well established that in addition to serving as food, the grape is a major source of several phytochemicals. The main biologically active and well-characterized constituent from the grape is resveratrol, which is known for various medicinal properties in human diseases. This review discusses the roles of various grape-derived phytochemicals in relation to various diseases.

Composition of Artificial Tear Solution Affects <i>In Vitro Pseudomonas aeruginosa</i> Biofilm Formation on Silicone Hydrogel Lens

Yadav, Mukesh Kumar,Chuck, Roy S.,Park, Choul Yong Mary Ann Liebert 2013 Journal of ocular pharmacology and therapeutics Vol.29 No.6

<P>To investigate Pseudomonas aeruginosa biofilm formation on silicone hydrogel contact lens in various artificial tears.</P>

Biological and Medicinal Properties of Grapes and Their Bioactive Constituents: An Update

Yadav, Mukesh,Jain, Shalini,Bhardwaj, Aarti,Nagpal, Ravinder,Puniya, Monica,Tomar, Radha,Singh, Vinod,Parkash, Om,Prasad, G.B.K.S.,Marotta, Francesco,Yadav, Hariom The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.3

The grape is one of the most valued conventional fruits, worldwide. Although most of the parts of the grapevine are useful, primarily, the grape is considered as a source of unique natural products not only for the development of valuable medicines against a number of diseases, but also for manufacturing various industrial products. Over the last few decades, apart from the chemistry of grape compounds, considerable progress has been made towards exploring the biological activities of various grape-derived constituents. Today, it is well established that in addition to serving as food, the grape is a major source of several phytochemicals. The main biologically active and well-characterized constituent from the grape is resveratrol, which is known for various medicinal properties in human diseases. This review discusses the roles of various grape-derived phytochemicals in relation to various diseases.

Protective Effect of Hexane and Ethanol Extract of <i>Piper Longum</i> L. on Gentamicin-Induced Hair Cell Loss in Neonatal Cultures

Yadav, Mukesh Kumar,Choi, June,Song, Jae-Jun Korean Society of Otorhinolaryngology-Head and Nec 2014 Clinical and Experimental Otorhinolaryngology Vol.7 No.1

<P><B>Objectives</B></P><P>Gentamicin (GM) is a commonly used aminoglycoside antibiotic that generates free oxygen radicals within the inner ear, which can cause vestibulo-cochlear toxicity and permanent damage to the sensory hair cells and neurons. <I>Piper longum</I> L. (PL) is a well-known spice and traditional medicine in Asia and Pacific islands, which has been reported to exhibit a wide spectrum of activity, including antioxidant activity. In this study, we evaluated the effect of hexane:ethanol (2:8) PL extract (subfraction of PL [SPL] extract) on GM-induced hair cell loss in basal, middle and apical regions in a neonatal cochlea cultures.</P><P><B>Methods</B></P><P>The protective effects of SPL extract were measured by phalloidin staining of cultures from postnatal day 2-3 mice with GM-induced hair cell loss. The anti-apoptosis activity of SPL extract was measured using double labeling by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and myosin-7a staining. The radical-scavenging activity of SPL extract was assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay.</P><P><B>Results</B></P><P>SPL extract at a concentration of 1 µg/mL significantly inhibited GM-induced hair cell loss at basal and middle region of cochlea, while 5 µg/mL was effective against apical region hair cell loss. The protective effect of SPL extract was concentration dependent and hair cells retained their stereocilia in explants treated with SPL extract prior to treatment with 0.3 mM GM. SPL extract decreased GM-induced apoptosis of hair cells as assessed by TUNEL staining. The outer hair and inner hair counts were not decreased in SPL extract treated groups in compare to GM treated explants. Additionally, SPL extract showed concentration dependent radical scavenging activity in a DPPH assay.</P><P><B>Conclusion</B></P><P>An anti-apoptosis effect and potent radical scavenger activity of SPL extract protects from GM-induced hair cell loss at basal, middle and apical regions in neonatal cochlea cultures.</P>

Role of Riboflavin in Induced Resistance against Fusarium Wilt and Charcoal Rot Diseases of Chickpea

Ratul Saikia,yadav mukesh kumar,Saju Varghese,Bhim Pratap Singh,Dip K Gogoi,Rakesh Kumar,Dilip K Arora 한국식물병리학회 2006 Plant Pathology Journal Vol.22 No.4

Riboflavin caused induction of systemic resistance inchickpea against Fusarium wilt and charcoal rotdiseases. The dose effect of 0.01 to 20 mM riboflavinshowed that 1.0 mM concentration was sufficient formaximum induction of resistance; higher concentrationdid not increase the effect. At this concentration,riboflavin neither caused cell death of the host plant nordirectly affected the pathogen’s growth. In time courseobservation, it was observed that riboflavin treatedchickpea plants were inducing resistance 2 days aftertreatment and reached its maximum level from 5 to 7days and then decreased. Riboflavin had no effect onsalicylic acid (SA) levels in chickpea, however, riboflavininduced plants found accumulation of phenolsand a greater activities of phenylalanine ammonia lyase(PAL) and pathogenesis related (PR) protein, peroxidasewas observed in induced plant than the control. Riboflavin pre-treated plants challenged with thepathogens exhibited maximum activity of the peroxidases4 days after treatment. Molecular weight of thepurified peroxidase was 42 kDa. From these studies wedemonstrated that riboflavin induced resistance is PRproteinmediated but is independent of salicylic acid.

Role of Riboflavin in Induced Resistance against Fusarium Wilt and Charcoal Rot Diseases of Chickpea

Saikia Ratul,Yadav Mukesh,Varghese Saju,Singh Bhim Pratap,Gogoi Dip K,Kumar Rakesh,Arora Dilip K The Korean Society of Plant Pathology 2006 Plant Pathology Journal Vol.22 No.4

Riboflavin caused induction of systemic resistance in chickpea against Fusarium wilt and charcoal rot diseases. The dose effect of 0.01 to 20 mM riboflavin showed that 1.0 mM concentration was sufficient for maximum induction of resistance; higher concentration did not increase the effect. At this concentration, riboflavin neither caused cell death of the host plant nor directly affected the pathogen's growth. In time course observation, it was observed that riboflavin treated chickpea plants were inducing resistance 2 days after treatment and reached its maximum level from 5 to 7 days and then decreased. Riboflavin had no effect on salicylic acid(SA) levels in chickpea, however, riboflavin induced plants found accumulation of phenols and a greater activities of phenylalanine ammonia lyase(PAL) and pathogenesis related(PR) protein, peroxidase was observed in induced plant than the control. Riboflavin pre-treated plants challenged with the pathogens exhibited maximum activity of the peroxidases 4 days after treatment. Molecular weight of the purified peroxidase was 42 kDa. From these studies we demonstrated that riboflavin induced resistance is PR-protein mediated but is independent of salicylic acid.

Living donor liver transplant outcomes during the COVID-19 pandemic: does a decrease in case volume impact the overall outcomes?

Shweta A. Singh,Hetal Pampaniya,Vikram Kumar,Mukesh Kumar,Shekhar Singh Jadaun,Vivek Yadav,Sanjiv Saigal,Subhash Gupta 대한이식학회 2022 Korean Journal of Transplantation Vol.36 No.2

Background: High-volume centers (HVCs) are classically associated with better out- comes. During the coronavirus disease 2019 (COVID-19) pandemic, there has been a decrease in the regular liver transplantation (LT) activity at our center. This study ana- lyzed the effect of the decline in LT on posttransplant patient outcomes at our HVC. Methods: We compared the surgical outcomes of patients who underwent LT during the COVID-19 pandemic lockdown (April 1, 2020 to September 30, 2020) with outcomes in the pre-pandemic calendar year (April 1, 2019 to March 31, 2020). Results: During the 6 months of pandemic lockdown, 60 patients underwent LT (43 adults and 17 children) while 228 patients underwent LT (178 adults and 50 children) during the pre-pandemic calendar year. Patients in the pandemic group had significant- ly higher model for end-stage liver disease (MELD) scores (24.39±9.55 vs. 21.14±9.17, P=0.034), Child-Turcotte-Pugh scores (11.46±2.32 vs. 10.25±2.24, P=0.03), and inci- dence of acute-on-chronic liver failure (30.2% vs. 10.2%, P=0.002). Despite performing LT in sicker patients with COVID-19-related challenges, the 30-day (14% vs. 18.5%, P=0.479), 3-month (16.3% vs. 20.2%, P=0.557), and 6-month mortality rates (23.3% vs. 28.7%, P=0.477) were lower, but not statistically significant when compared to the pre-pandemic cohort. Conclusions: During the COVID-19 pandemic lockdown the number of LT procedures performed at our HVC declined by half because prevailing conditions allowed LT in very sick patients only. Despite these changes, outcomes were not inferior during the pan- demic period compared to the pre-pandemic calendar year. Greater individualization of patient care contributed to non-inferior outcomes in these sick recipients.

Stem Rot of Pearl Millet Prevalence, Symptomatology, Disease Cycle, Disease Rating Scale and Pathogen Characterization in Pearl Millet-Klebsiella Pathosystem

Vinod Kumar Malik,Pooja Sangwan,Manjeet Singh,Pavitra Kumari,Niharika Shoeran,Navjeet Ahalawat,Mukesh Kumar,Harsh Deep,Kamla Malik,Preety Verma,Pankaj Yadav,Sheetal Kumari,Aakash,Sambandh Dhal 한국식물병리학회 2024 Plant Pathology Journal Vol.40 No.1

The oldest and most extensively cultivated form of millet, known as pearl millet (<i>Pennisetum glaucum</i> (L.) R. Br. Syn. <i>Pennisetum americanum</i> (L.) Leeke), is raised over 312.00 lakh hectares in Asian and African countries. India is regarded as the significant hotspot for pearl millet diversity. In the Indian state of Haryana, where pearl millet is grown, a new and catastrophic bacterial disease known as stem rot of pearl millet spurred by the bacterium <i>Klebsiella aerogenes</i> (formerly <i>Enterobacter</i>) was first observed during fall 2018. The disease appears in form of small to long streaks on leaves, lesions on stem, and slimy rot appearance of stem. The associated bacterium showed close resemblance to <i>Klebsiella aerogenes</i> that was confirmed by a molecular evaluation based on 16S rDNA and gyrA gene nucleotide sequences. The isolates were also identified to be <i>Klebsiella aerogenes</i> based on biochemical assays, where Klebsiella isolates differed in D-trehalose and succinate alkalisation tests. During fall 2021-2023, the disease has spread all the pearl millet-growing districts of the state, extending up to 70% disease incidence in the affected fields. The disease is causing considering grain as well as fodder losses. The proposed scale, consisting of six levels (0-5), is developed where scores 0, 1, 2, 3, 4, and 5 have been categorized as highly resistant, resistant, moderately resistant, moderately susceptible, susceptible, and highly susceptible disease reaction, respectively. The disease cycle, survival of pathogen, and possible losses have also been studied to understand other features of the disease.