Anand Kumar

Dr. Anand Kumar

Biosecurity and Public Health Group, Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87544, USA
orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 February 2016 in The Journal of Immunology
Verified
Journal Article
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SKSukumar Kandasamy
Sukumar Kandasamy
AVAnastasia N. Vlasova
Anastasia N. Vlasova
DFDavid Fischer
David Fischer
Anand KumarAnand Kumar
Anand Kumar
KCKuldeep S. Chattha
Kuldeep S. Chattha
LSLinda J. Saif
Linda J. Saif
Rotavirus (RV) causes significant morbidity and mortality in children worldwide. The intestinal microbiota plays an important role in modulating host–pathogen interactions, but little is known about the impact of commonly used probiotics on human RV (HRV) infection. In this study, we compared the immunomodulatory effects of Gram-positive (Lactobacillus rhamnosus strain GG [LGG]) and Gram-negative (Escherichia coli Nissle [EcN]) probiotic bacteria on virulent human rotavirus (VirHRV) infection and immunity using neonatal gnotobiotic piglets. Gnotobiotic piglets were colonized with EcN, LGG, or EcN+LGG or uncolonized and challenged with VirHRV. Mean peak virus shedding titers and mean cumulative fecal scores were significantly lower in EcN-colonized compared with LGG-colonized or uncolonized piglets. Reduced viral shedding titers were correlated with significantly reduced small intestinal HRV IgA Ab responses in EcN-colonized compared with uncolonized piglets post-VirHRV challenge. However the total IgA levels post-VirHRV challenge in the intestine and pre-VirHRV challenge in serum were significantly higher in EcN-colonized than in LGG-colonized piglets. In vitro treatment of mononuclear cells with these probiotics demonstrated that EcN, but not LGG, induced IL-6, IL-10, and IgA, with the latter partially dependent on IL-10. However, addition of exogenous recombinant porcine IL-10 + IL-6 to mononuclear cells cocultured with LGG significantly enhanced IgA responses. The greater effectiveness of EcN in moderating HRV infection may also be explained by the binding of EcN but not LGG to Wa HRV particles or HRV 2/4/6 virus-like particles but not 2/6 virus-like particles. Results suggest that EcN and LGG differentially modulate RV infection and B cell responses.

25 September 2019 in Genes
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Journal Article
Open access
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Manmeet RawatManmeet Rawat
Manmeet Rawat
KKKavita Kadian
Kavita Kadian
Yash GuptaYash Gupta
Yash Gupta
Anand KumarAnand Kumar
Anand Kumar
PCpatrick chain
patrick chain
GPGulshan Parasher
Gulshan Parasher
Pancreatic cancer is one of the most aggressive malignancies, accounting for more than 45,750 deaths annually in the U.S. alone. The aggressive nature and late diagnosis of pancreatic cancer, coupled with the limitations of existing chemotherapy, present the pressing need for the development of novel therapeutic strategies. Recent reports have demonstrated a critical role of microRNAs (miRNAs) in the initiation, progression, and metastasis of cancer. Furthermore, aberrant expressions of miRNAs have often been associated with the cause and consequence of pancreatic cancer, emphasizing the possible use of miRNAs in the effective management of pancreatic cancer patients. In this review, we provide a brief overview of miRNA biogenesis and its role in fundamental cellular process and miRNA studies in pancreatic cancer patients and animal models. Subsequent sections narrate the role of miRNA in, (i) cell cycle and proliferation; (ii) apoptosis; (iii) invasions and metastasis; and (iv) various cellular signaling pathways. We also describe the role of miRNA’s in pancreatic cancer; (i) diagnosis; (ii) prognosis and (iii) therapeutic intervention. Conclusion section describes the gist of review with future directions.

17 September 2024 in Foods
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Journal Article
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Anand KumarAnand Kumar
Anand Kumar
KGKatelyn M. Green
Katelyn M. Green
Manmeet RawatManmeet Rawat
Manmeet Rawat
The increasing interest in postbiotics, a term gaining recognition alongside probiotics and prebiotics, aligns with a growing number of clinical trials demonstrating positive outcomes for specific conditions. Postbiotics present several advantages, including safety, extended shelf life, ease of administration, absence of risk, and patentability, making them more appealing than probiotics alone. This review covers various aspects, starting with an introduction, terminology, classification of postbiotics, and brief mechanisms of action. It emphasizes microbial metabolomics as the initial step in discovering novel postbiotics. Commonly employed techniques such as NMR, GC-MS, and LC-MS are briefly outlined, along with their application principles and limitations in microbial metabolomics. The review also examines existing research where these techniques were used to identify, isolate, and characterize postbiotics derived from different microbial sources. The discovery section concludes by highlighting challenges and future directions to enhance postbiotic discovery. In the second half of the review, we delve deeper into numerous published postbiotic clinical trials to date. We provide brief overviews of system-specific trial applications, their objectives, the postbiotics tested, and their outcomes. The review concludes by highlighting ongoing applications of postbiotics in extended clinical trials, offering a comprehensive overview of the current landscape in this evolving field.

1 December 2014 in Foodborne Pathogens and Disease
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Journal Article
Closed access
DMDixie F. Mollenkopf
Dixie F. Mollenkopf
JCJohana K. Cenera
Johana K. Cenera
EBErin M. Bryant
Erin M. Bryant
CKChristy A. King
Christy A. King
IKIsaac Kashoma
Isaac Kashoma
TWThomas E. Wittum
Thomas E. Wittum
We investigated the implied health benefits of retail chicken breast labeled as "organic" or "antibiotic-free" when compared to conventional products based on frequency of contamination by Salmonella spp., Campylobacter spp., and coliform bacteria resistant to fluoroquinolones, extended-spectrum cephalosporins, or carbapenems. We purchased 231 prepackaged chicken breasts from 99 grocery stores representing 17 retail chains in Ohio, Michigan, and Pennsylvania from June to September 2012. Ninety-six (41.5%) packages were labeled "antibiotic free" and 40 (17.3%) were labeled "organic," with the remaining 95 (41.1%) making neither label claim. Salmonella were recovered from 56 (24.2%) packages, and the recovery rate was not different between product types. Five percent of packages contained Salmonella carrying the extended-spectrum cephalosporin resistance gene bla(CMY-2), representing 21.4% of Salmonella isolates. Campylobacter spp. were recovered from 10.8% of packages, with observed recovery rates similar for the three product types. Using selective media, we recovered Escherichia coli harboring bla(CMY-2) from over half (53.7%) of packages, with similar recovery rates for all product types. In addition, we recovered E. coli carrying bla(CTX-M) from 6.9% of packages, and E. coli with QRDR mutations from 8.2% of packages. Fluoroquinolone-resistant E. coli recovered using selective media were more common (p<0.05) in conventional (18.9%) compared to organic (0) and antibiotic-free (2.1%) packages. Our results indicate that, regardless of product type, fresh retail chicken breast is commonly contaminated with enteric pathogens associated with foodborne illness and commensal bacteria harboring genes conferring resistance to critically important antimicrobial drugs.

12 November 2015 in Frontiers in Microbiology
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Journal Article
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IKIsaac P. Kashoma
Isaac P. Kashoma
IKIssmat Kassem
Issmat Kassem
Anand KumarAnand Kumar
Anand Kumar
BKBeda M. Kessy
Beda M. Kessy
WGWondwossen Gebreyes
Wondwossen Gebreyes
GRGireesh Rajashekara
Gireesh Rajashekara
Foodborne Campylobacter infections pose a serious threat to public health worldwide. However, the occurrence and characteristics of Campylobacter in food animals and products remain largely unknown in Tanzania. The objective of this study was to determine the prevalence, antibiotic resistance, and genetic profiles (sequence types, STs) of Campylobacter isolated from feces of pigs and dairy and beef cattle in Tanzania. Overall, 259 (~ 30%) of 864 samples were positive for Campylobacter spp, which were detected in 32.5%, 35.4%, and 19.6% of the pig, dairy, and beef cattle samples, respectively. Multiplex PCR analysis identified 64.5% and 29.3% of the Campylobacter isolates as C. coli and C. jejuni, respectively. The majority (91.9%) of the isolates from pig samples were identified as C. coli, while C. jejuni accounted for 65.5% of the isolates from cattle. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method revealed resistance to: ampicillin (70% and 76%), gentamicin (1.8% and 12.6%, respectively), streptomycin (65.8% and 74.8%), erythromycin (41.4% and 48.7%), tetracycline (18.9% and 23.4%), and ciprofloxacin (14.4% and 7.2%). Resistance to nalidixic acid (39.6%), azithromycin (13.5%), and chloramphenicol (4.5%) was determined using the disk diffusion assay only, while resistance to tylosin (38.7%) was quantified using the broth microdilution method. Multilocus sequence typing of 111 Campylobacter isolates resulted in the identification of 48 STs (26 C. jejuni and 22 C. coli) of which 7 were novel (6 C. jejuni and 1 C. coli). Taken together, this study revealed the high prevalence, genetic diversity and antimicrobial resistance of Campylobacter in important food animals in Tanzania, which highlights the urgent need for the surveillance and control of Campylobacter in this country.

26 April 2017 in mSphere
Verified
Journal Article
Open access
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AVAnastasia N. Vlasova
Anastasia N. Vlasova
FPFrancine C. Paim
Francine C. Paim
SKSukumar Kandasamy
Sukumar Kandasamy
MAMoyasar A. Alhamo
Moyasar A. Alhamo
DFDavid D. Fischer
David D. Fischer
LSLinda J. Saif
Linda J. Saif
Malnutrition affects millions of children in developing countries, compromising immunity and contributing to increased rates of death from infectious diseases. Rotavirus is a major etiological agent of childhood diarrhea in developing countries, where malnutrition is prevalent. However, the interactions between the two and their combined effects on immune and intestinal functions are poorly understood. In this study, we used neonatal gnotobiotic (Gn) pigs transplanted with the fecal microbiota of a healthy 2-month-old infant (HIFM) and fed protein-deficient or -sufficient bovine milk diets. Protein deficiency induced hypoproteinemia, hypoalbuminemia, hypoglycemia, stunting, and generalized edema in Gn pigs, as observed in protein-malnourished children. Irrespective of the diet, human rotavirus (HRV) infection early, at HIFM posttransplantation day 3 (PTD3), resulted in adverse health effects and higher mortality rates (45 to 75%) than later HRV infection (PTD10). Protein malnutrition exacerbated HRV infection and affected the morphology and function of the small intestinal epithelial barrier. In pigs infected with HRV at PTD10, there was a uniform decrease in the function and/or frequencies of natural killer cells, plasmacytoid dendritic cells, and CD103+ and apoptotic mononuclear cells and altered gene expression profiles of intestinal epithelial cells (chromogranin A, mucin 2, proliferating cell nuclear antigen, SRY-Box 9, and villin). Thus, we have established the first HIFM-transplanted neonatal pig model that recapitulates major aspects of protein malnutrition in children and can be used to evaluate physiologically relevant interventions. Our findings provide an explanation of why nutrient-rich diets alone may lack efficacy in malnourished children. IMPORTANCE Malnutrition and rotavirus infection, prevalent in developing countries, individually and in combination, affect the health of millions of children, compromising their immunity and increasing the rates of death from infectious diseases. However, the interactions between the two and their combined effects on immune and intestinal functions are poorly understood. We have established the first human infant microbiota-transplanted neonatal pig model of childhood malnutrition that reproduced the impaired immune, intestinal, and other physiological functions seen in malnourished children. This model can be used to evaluate relevant dietary and other health-promoting interventions. Our findings provide an explanation of why adequate nutrition alone may lack efficacy in malnourished children.