1.A Review on Chemical-Induced Inflammatory Bowel Disease Models in Rodents.
Puneet Kaur RANDHAWA ; Kavinder SINGH ; Nirmal SINGH ; Amteshwar Singh JAGGI
The Korean Journal of Physiology and Pharmacology 2014;18(4):279-288
Ulcerative colitis and Crohn's disease are a set of chronic, idiopathic, immunological and relapsing inflammatory disorders of the gastrointestinal tract referred to as inflammatory bowel disorder (IBD). Although the etiological factors involved in the perpetuation of IBD remain uncertain, development of various animal models provides new insights to unveil the onset and the progression of IBD. Various chemical-induced colitis models are widely used on laboratory scale. Furthermore, these models closely mimic morphological, histopathological and symptomatical features of human IBD. Among the chemical-induced colitis models, trinitrobenzene sulfonic acid (TNBS)-induced colitis, oxazolone induced-colitis and dextran sulphate sodium (DSS)-induced colitis models are most widely used. TNBS elicits Th-1 driven immune response, whereas oxazolone predominantly exhibits immune response of Th-2 phenotype. DSS-induced colitis model also induces changes in Th-1/Th-2 cytokine profile. The present review discusses the methodology and rationale of using various chemical-induced colitis models for evaluating the pathogenesis of IBD.
Acetic Acid
;
Colitis
;
Colitis, Ulcerative
;
Crohn Disease
;
Dextrans
;
Gastrointestinal Tract
;
Humans
;
Inflammatory Bowel Diseases*
;
Models, Animal
;
Oxazolone
;
Phenotype
;
Rodentia*
;
Sodium
2.Neurogenic pathways in remote ischemic preconditioning induced cardioprotection: Evidences and possible mechanisms.
Amritpal Singh AULAKH ; Puneet Kaur RANDHAWA ; Nirmal SINGH ; Amteshwar Singh JAGGI
The Korean Journal of Physiology and Pharmacology 2017;21(2):145-152
Remote ischemic preconditioning (RIPC) is an intrinsic phenomenon whereby 3~4 consecutive ischemia-reperfusion cycles to a remote tissue (noncardiac) increases the tolerance of the myocardium to sustained ischemiareperfusion induced injury. Remote ischemic preconditioning induces the local release of chemical mediators which activate the sensory nerve endings to convey signals to the brain. The latter consequently stimulates the efferent nerve endings innervating the myocardium to induce cardioprotection. Indeed, RIPC-induced cardioprotective effects are reliant on the presence of intact neuronal pathways, which has been confirmed using nerve resection of nerves including femoral nerve, vagus nerve, and sciatic nerve. The involvement of neurogenic signaling has been further substantiated using various pharmacological modulators including hexamethonium and trimetaphan. The present review focuses on the potential involvement of neurogenic pathways in mediating remote ischemic preconditioning-induced cardioprotection.
Brain
;
Femoral Nerve
;
Hexamethonium
;
Ischemic Preconditioning*
;
Myocardium
;
Negotiating
;
Nerve Endings
;
Neurons
;
Sciatic Nerve
;
Sensory Receptor Cells
;
Trimethaphan
;
Vagus Nerve
3.Conditioning-induced cardioprotection: Aging as a confounding factor.
Puneet Kaur RANDHAWA ; Anjana BALI ; Jasleen Kaur VIRDI ; Amteshwar Singh JAGGI
The Korean Journal of Physiology and Pharmacology 2018;22(5):467-479
The aging process induces a plethora of changes in the body including alterations in hormonal regulation and metabolism in various organs including the heart. Aging is associated with marked increase in the vulnerability of the heart to ischemia-reperfusion injury. Furthermore, it significantly hampers the development of adaptive response to various forms of conditioning stimuli (pre/post/remote conditioning). Aging significantly impairs the activation of signaling pathways that mediate preconditioning-induced cardioprotection. It possibly impairs the uptake and release of adenosine, decreases the number of adenosine transporter sites and down-regulates the transcription of adenosine receptors in the myocardium to attenuate adenosine-mediated cardioprotection. Furthermore, aging decreases the expression of peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC-1α) and subsequent transcription of catalase enzyme which subsequently increases the oxidative stress and decreases the responsiveness to preconditioning stimuli in the senescent diabetic hearts. In addition, in the aged rat hearts, the conditioning stimulus fails to phosphorylate Akt kinase that is required for mediating cardioprotective signaling in the heart. Moreover, aging increases the concentration of Na⁺ and K⁺, connexin expression and caveolin abundance in the myocardium and increases the susceptibility to ischemia-reperfusion injury. In addition, aging also reduces the responsiveness to conditioning stimuli possibly due to reduced kinase signaling and reduced STAT-3 phosphorylation. However, aging is associated with an increase in MKP-1 phosphorylation, which dephosphorylates (deactivates) mitogen activated protein kinase that is involved in cardioprotective signaling. The present review describes aging as one of the major confounding factors in attenuating remote ischemic preconditioning-induced cardioprotection along with the possible mechanisms.
Adenosine
;
Aging*
;
Animals
;
Catalase
;
Heart
;
Metabolism
;
Myocardium
;
Negotiating
;
Oxidative Stress
;
Phosphorylation
;
Phosphotransferases
;
PPAR gamma
;
Protein Kinases
;
Rats
;
Receptors, Purinergic P1
;
Reperfusion Injury
4.Metagenomics Analysis of Thrombus Samples Retrieved from Mechanical Thrombectomy
Atulabh VAJPEYEE ; Puneet Singh CHAUHAN ; Swapnil PANDEY ; Shivam TIWARI ; Lokendra Bahadur YADAV ; Akhilesh Kumar SHROTI ; Manisha VAJPEYEE
Neurointervention 2021;16(1):39-45
Purpose:
The purpose of this study was to assess the microbiota in middle cerebral artery thrombi retrieved in mechanical thrombectomy arising out of symptomatic carotid plaque within 6 hours of acute ischemic stroke. Thrombi were subjected to next-generation sequencing for a bacterial signature to determine their role in atherosclerosis.
Materials and Methods:
We included 4 human middle cerebral artery thrombus samples (all patients were male). The median age for the patients was 51±13.6 years. Patients enrolled in the study from Pacific Medical University and Hospital underwent mechanical thrombectomy in the stroke window period. All patients underwent brain magnetic resonance angiography (MRA) and circle of Willis and neck vessel MRA along with the standard stroke workup to establish stroke etiology. Only patients with symptomatic carotid stenosis and tandem lesions with ipsilateral middle cerebral artery occlusion were included in the study. Thrombus samples were collected, stored at –80 degrees, and subjected to metagenomics analysis.
Results:
Of the 4 patients undergoing thrombectomy for diagnosis with ischemic stroke, all thrombi recovered for bacterial DNA in qPCR were positive. More than 27 bacteria were present in the 4 thrombus samples. The majority of bacteria were Lactobacillus, Stenotrophomonas, Pseudomonas, Staphylococcus, and Finegoldia.
Conclusion
Genesis of symptomatic atherosclerotic carotid plaque leading to thromboembolism could be either due to direct mechanisms like acidification and local inflammation of plaque milieu with lactobacillus, biofilm dispersion leading to inflammation like with pseudomonas fluorescence, or enterococci or indirect mechanisms like Toll 2 like signaling by gut microbiota.
5.Pediatric Headache: A Comprehensive Review
Arvinder WANDER ; Ankit Kumar MEENA ; Puneet Kumar CHOUDHARY ; Sameer PEER ; Ramandeep SINGH
Annals of Child Neurology 2024;32(4):207-218
Pediatric headache is a common condition that often results in frequent outpatient visits. There are two broad etiological groups of headaches—primary and secondary headaches—with the former being more prevalent. Migraine, a type of primary headache, shares similarities with those experienced by adults, albeit with some variations in diagnostic criteria. The secondary causes of headache should be differentiated from the primary headaches with proper clinical evaluation and focussed investigations. The management of migraine focusses on lifestyle modifications, behavioral therapy, and pharmacotherapy for acute episodes and long-term preventive therapy. There are many novel promising treatment modalities. This review article provides an overview of pediatric headache epidemiology, classification, and pathophysiology and then elaborates on management and prevention strategies.
6.Coexistence of pneumothorax and Chilaiditi sign: a case report.
Nitin TANGRI ; Sameer SINGHAL ; Priyanka SHARMA ; Dinesh MEHTA ; Sachin BANSAL ; Neeraj BHUSHAN ; Sulbha SINGLA ; Puneet SINGH
Asian Pacific Journal of Tropical Biomedicine 2014;4(1):75-77
We present a case of 50 year old male patient with coexistence of Pneumothorax and Chilaiditi sign. Chilaiditi sign is an incidental radiographic finding of a usually asymptomatic condition in which a part of intestine is located between the liver and diaphragm; however, the term "Chilaiditi syndrome" is used for symptomatic hepatodiaphragmatic interposition. The patient had no symptoms of abdominal pain, constipation, diarrhea, or emesis. Incidentally, Chilaiditi sign was diagnosed on chest radiography. Pneumothorax is defined as air in the pleural space. Pneumothoraces are classified as spontaneous or traumatic. Spontaneous pneumothorax is labelled as primary when no underlying lung disease is present, or secondary, when it is associated with pre-existing lung disease. Our case is the rare in the literature indicating the coexistence of Chilaiditi sign and pneumothorax.
Chest Pain
;
Chilaiditi Syndrome
;
complications
;
diagnosis
;
Dyspnea
;
Humans
;
Male
;
Middle Aged
;
Pneumothorax
;
complications
;
diagnosis
7.Polygenic Risk Score for Cardiovascular Diseases in Artificial Intelligence Paradigm: A Review
Narendra N KHANNA ; Manasvi SINGH ; Mahesh MAINDARKAR ; Ashish KUMAR ; Amer M. JOHRI ; Laura MENTELLA ; John R LAIRD ; Kosmas I. PARASKEVAS ; Zoltan RUZSA ; Narpinder SINGH ; Mannudeep K. KALRA ; Jose Fernandes E. FERNANDES ; Seemant CHATURVEDI ; Andrew NICOLAIDES ; Vijay RATHORE ; Inder SINGH ; Jagjit S. TEJI ; Mostafa AL-MAINI ; Esma R. ISENOVIC ; Vijay VISWANATHAN ; Puneet KHANNA ; Mostafa M. FOUDA ; Luca SABA ; Jasjit S. SURI
Journal of Korean Medical Science 2023;38(46):e395-
Cardiovascular disease (CVD) related mortality and morbidity heavily strain society. The relationship between external risk factors and our genetics have not been well established.It is widely acknowledged that environmental influence and individual behaviours play a significant role in CVD vulnerability, leading to the development of polygenic risk scores (PRS). We employed the PRISMA search method to locate pertinent research and literature to extensively review artificial intelligence (AI)-based PRS models for CVD risk prediction.Furthermore, we analyzed and compared conventional vs. AI-based solutions for PRS. We summarized the recent advances in our understanding of the use of AI-based PRS for risk prediction of CVD. Our study proposes three hypotheses: i) Multiple genetic variations and risk factors can be incorporated into AI-based PRS to improve the accuracy of CVD risk predicting. ii) AI-based PRS for CVD circumvents the drawbacks of conventional PRS calculators by incorporating a larger variety of genetic and non-genetic components, allowing for more precise and individualised risk estimations. iii) Using AI approaches, it is possible to significantly reduce the dimensionality of huge genomic datasets, resulting in more accurate and effective disease risk prediction models. Our study highlighted that the AI-PRS model outperformed traditional PRS calculators in predicting CVD risk. Furthermore, using AI-based methods to calculate PRS may increase the precision of risk predictions for CVD and have significant ramifications for individualized prevention and treatment plans.