ABSTRACT
RATIONALE: Alzheimer's disease (AD), an age-dependent devastating neuropsychiatric disorder, is a leading cause of learning, memory and intellectual disabilities. Current therapeutic approaches for the amelioration of the anomalies of AD are not effective. OBJECTIVE: In the present study, the molecular mechanisms underlying sporadic AD (sAD), the memory related behavioral analysis and neuroprotective effects of Ellagic acid (EA) were investigated. METHOD: sAD mouse model was developed by intracerebroventricular (ICV) injection of Streptozotocin (STZ). The efficacy of EA, a naturally occurring polyphenol, in amelioration of anomalies associated with sAD was assessed. EA was administered once daily for 28 days at a dose of 75 mg/kg body weight followed by neurobehavioral, biochemical, molecular and neuronal count analysis to delineate the mode of action of EA. RESULT: The ICV injection of STZ in mice significantly increased the expression of AD biomarkers in addition to enhanced oxidative stress. A decline in the discrimination index in Novel Object Recognition Test was observed indicating the compromise of recognition memory in AD. Studies on the expression of genes involved in synaptic plasticity reveal the dysregulation of the α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) of the glutamate and its scaffolding proteins in the postsynaptic density and thereby synaptic plasticity in AD. ICV-STZ led to significant upregulation of apoptotic markers which led to decrease in neuronal density of the cerebral cortex. EA significantly reversed the above and improved anomalies of sAD. CONCLUSION: EA was observed to profoundly modulate the genes involved in AD pathophysiology, restored antioxidant enzymes activity, reduced lipid peroxidation and neuronal loss in the sAD brain. Further, EA was observed to effectively modulate the genes involved in apoptosis and synaptic plasticity. Therefore, EA possesses promising anti-AD properties, which may improve AD-associated anomalies by modulating synaptic plasticity via AMPAR signaling.
Subject(s)
Alzheimer Disease , Cerebral Cortex , Disease Models, Animal , Ellagic Acid , Memory Disorders , Neuroprotective Agents , Oxidative Stress , Receptors, AMPA , Streptozocin , Animals , Alzheimer Disease/metabolism , Alzheimer Disease/drug therapy , Receptors, AMPA/metabolism , Mice , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Ellagic Acid/pharmacology , Ellagic Acid/administration & dosage , Male , Neuroprotective Agents/pharmacology , Neuroprotective Agents/administration & dosage , Memory Disorders/drug therapy , Memory Disorders/metabolism , Oxidative Stress/drug effects , Neuronal Plasticity/drug effectsABSTRACT
Clinical and epidemiological characteristics of SARS-CoV-2 infection are now widely available, but there are few data on longitudinal serology in large cohorts, particularly from low-and middle-income countries. We established an ongoing prospective cohort of 3840 SARS-CoV-2 RT-PCR positive individuals in the Delhi-National Capital Region of India, to document clinical and immunological characteristics during illness and convalescence. The IgG responses to the receptor binding domain (RBD) and nucleocapsid were assessed at 0-7, 10-28 days and 6-10 weeks after infection. The clinical predictors of seroconversion were identified by multivariable regression analysis. The seroconversion rates in the post-infection windows of 0-7 days, 10-28 days and 6-10 weeks were 46%, 84.7% and 85.3% respectively (n=782). The proportion with a serological response increased with severity of COVID-19 disease. All participants with severe disease, 89.6% with mild to moderate infection and 77.3% of asymptomatic participants had IgG antibodies to the RBD antigen. The threshold values in the nasopharyngeal viral RNA RT-PCR in a subset of asymptomatic and symptomatic seroconverters were comparable (p value: 0.48), with similar results among non-seroconverters (p value: 0.16) (n=169). This is the first report of longitudinal humoral immune responses to SARS-CoV-2 infection over a period of ten weeks from South Asia. The low seropositivity in asymptomatic participants and differences between assays highlight the importance of contextualizing the understanding of population serosurveys. SummaryWe measured anti-SARS-CoV-2 RBD and NC protein IgG in a multi-hospital-based prospective cohort from northern India up to ten weeks post-infection. The lower seroconversion rate among asymptomatic RT-PCR positive participants has public health significance particularly for interpreting community seroprevalence estimates.
ABSTRACT
Cryptococcus neoformans is the most frequent cause of fungal meningitis in humans. Cryptococcus affects people of all ages and has a worldwide distribution. It is the fourth most common infection in AIDS (CD4 counts <100/mm3). Cases also occur in patients with other forms of immunosuppression and in apparently immunocompetent individuals. Chronic high-dose steroid may precipitate such an immunocompromised state and thus create susceptibility to fungal infections. In our case, we describe a 14-year-old boy who was on steroids for tubercular meningitis for a period of 8â weeks after which he developed cryptococcal meningitis. Attention is drawn to the increasing number of reported cases of this disease which have been associated with steroid therapy and this possibility should be remembered when investigating patients with tubercular meningitis especially if they are being treated with steroids.
Subject(s)
Dexamethasone/adverse effects , Glucocorticoids/adverse effects , Meningitis, Cryptococcal/chemically induced , Opportunistic Infections/chemically induced , Adolescent , Antifungal Agents/therapeutic use , Diagnosis, Differential , Drug Therapy, Combination , HIV Seronegativity , Humans , Magnetic Resonance Imaging , Male , Meningitis, Cryptococcal/diagnosis , Meningitis, Cryptococcal/drug therapy , Opportunistic Infections/diagnosis , Opportunistic Infections/drug therapy , Tuberculosis, Miliary/diagnosisABSTRACT
Dubin-Johnson syndrome (DJS) is an autosomal recessive disorder characterised by conjugated hyperbilirubinemia resulting from mutations of ABCC2/MRP2 gene. The beneficial effects of ursodeoxycholic acid (UDCA) and rifampicin were found to be complementary in the treatment of cholestatic liver disease secondary to DJS. We present a case of a young woman with tubercular meningitis. She was started on modified antitubercular therapy in view of conjugated hyperbilirubinemia. However, reinitiation of rifampicin resulted in redevelopment of jaundice. Liver biopsy was suggestive of DJS. The patient was started on rifampicin along with UDCA. There was improvement in hyperbilirubinemia and a full course of antituberculous therapy without further worsening of the disorder was possible. This is a rare case of DJS with tuberculosis, showing beneficial effects of rifampicin and UDCA combination therapy, which so far has been considered doubtful. It is uncertain what the level of efficacy of therapy is in various MRP2 gene mutations.