Studies on the storage stability of fermented red dragon fruit (Hylocereus polyrhizus) drink

The objective of this work was to study the effect of storage temperatures and duration on the stability of fermented red dragon fruit drink (FRDFD) on its betacyanins content, physicochemical and microbiological qualities (BPM) and determining sensory acceptability. Results showed that both storage temperatures and duration have a significant effect on betacyanins content and physicochemical properties of FRDFD. Aerobic mesophilic and yeast and mold counts were lower than 1 × 103 CFU/mL for FRDFD stored at both temperatures. The loss of betanin (16.53–13.93 g/L) at 4 °C was 15.73% with no significant changes in physicochemical properties from week two onwards compared to 56.32% (16.53–7.22 g/L) of betanin loss at 25 °C. At week eight, FRDFD stored at 4 °C still contained 13.93 g/L betanin with a pH value of 3.46, suggested its potential as a functional drink which is sensory acceptable (mean score > 80% using hedonic test) among consumers

Study on bioaccessibility of betacyanins from red dragon fruit (Hylocereus polyrhizus)

Betacyanins are bioactive dietary phytochemicals which can be found in red dragon fruit (RDF). Therefore, the bioaccessibility of betacyanins that present in fermented red dragon fruit drink (RDFD) and pressed red dragon fruit juice (RDFJ) was accessed in simulated gastric and intestinal digestion. Results disclosed that betacyanins from RDFD and RDFJ suffered minor loss (< 25%) at gastric-like environment but greater loss was observed during the intestinal phase digestion. After subjected to intestinal digestion, RDFD retained 46.42% of betanin while RDFJ retained 43.76%, with betanin concentration of 17.12 mM and 12.37 mM, respectively. Findings also revealed that RDFD exhibited higher antioxidant capacity compared to RDFJ after subjected to intestinal digestion, with values of 0.88 mM Trolox equivalent antioxidant capacity (TEAC) and 0.85 mM TEAC, respectively. The data suggests that betacyanins that present in RDF are bioaccessible while fermentation able to enhance the bioavailability with more betacyanins retained after intestinal digestion

Fermentation of red dragon fruit (Hylocereus polyrhizus) for betalains concentration

Red dragon fruits (RDF) contain high levels of health-promoting betalains but its bioavailability in plasma is low (< 1.0%). Therefore, fermentation technique was adopted to improve the yield of betalains presenting in fermented red dragon fruit drink (FRDFD) via concentration. Fermentation of RDF was carried out with autochthonous strains. The objectives of present study were to evaluate 1) the effects of fermentation duration 2) white refined cane sugar to flesh ratio and 3) types of sugar on betalainic (betanin, isobetanin) and non-betalainic phenolic compounds in FRDFD using HPLC-DAD, total phenolic content (TPC) and total flavonoid content (TFC) assay. Results indicated that all fermentation parameters showed a significant effect (p < 0.05) on the yields of betalainic (betanin, isobetanin) and non-betalainic phenolic compounds in FRDFD. The best fermentation parameters were 7 days fermentation at 10% white refined cane sugar to flesh ratio. The highest concentration of betanin, TPC and TFC achieved were 131.68 g/L, 1136.85 mg GAE/100mL and 10.39 mg CE/100mL respectively. The concentration of betanin obtained through best fermentation parameters (131.68 g/L) in present study has increased nine-fold compared to non-optimized fermentation (14.23 g/L). This indicated that fermentation is a potential economic processing technique to concentrate bioactive compounds present in functional drinks

Immunological determinants of tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) in HIV-infected patients on antiretroviral therapy / Tan Hong Yien

The advent of combined antiretroviral therapy (cART) has improved the quality of life of human immunodeficiency virus (HIV)-infected individuals by suppressing viral replication leading to reconstitution of the immune system. However, patients initiated on cART at an immunodeficient state i.e. CD4+ T-cell counts <200 cells/μL, may experience immune reconstitution inflammatory syndrome (IRIS) characterized by exaggerated inflammatory responses against an existing opportunistic infection (OI). Tuberculosis (TB) represents the most common OI among individuals with HIV infection, especially in resource-limited settings. TB-associated IRIS (TB-IRIS) often manifests as paradoxical deterioration of treated TB (also known as paradoxical TBIRIS), or rapid onset of newly diagnosed TB following cART initiation (also known as unmasking TB-IRIS). Notwithstanding that 10–30% of TB-HIV co-infected patients may develop TB-IRIS, there has not been a report from Malaysia, heretofore. Hence, a retrospective investigation was conducted. The prevalence of TB-IRIS was 16% among TB-HIV coinfected patients at the University Malaya Medical Centre (UMMC). Only disseminated TB was predictive of TB-IRIS (OR=10.7, P=0.032), and that the mortality rates were similar between patients with TB-IRIS (n=1, 5.9%) and TB-HIV without IRIS (n=5, 5.7%). CD4+ T-cell recovery following ART was not different between the two groups. TB-IRIS reportedly occurs within the first month of ART, and hence it is cumbersome to distinguish it from relapsed or newly acquired TB. Therefore, there is an urgent need to identify appropriate laboratory markers to predict and characterize TB-IRIS. In a prospective cohort at UMMC, a case-control study that comprised the following study groups was established: (1) TB-IRIS (case) (2) TB no IRIS (control) (3) No TB or IRIS (control) The levels of twelve cytokines/pro-inflammatory mediators at baseline and at the event of TB-IRIS (or equivalent time-point for control) were compared among the three groups. We found that the plasma IL-18 was higher in TB-IRIS patients at pre-cART and during the event. CXCL10 was higher pre-cART (P<0.001), mainly in paradoxical TB-IRIS patients, and during TB-IRIS (P<0.001), whereas CXCL8 was only higher during TB-IRIS (P<0.001). In contrast, IFN-γ was lower before and during TB-IRIS. Receiver operating curve (ROC) analysis showed that CXCL10 (AUC=0.884, P<0.0001) and IL-18 (AUC=0.99, P<0.0001) at pre-cART were predictive of TB-IRIS. Since IL-18 is the signature cytokine for inflammasome activation in monocyte/macrophage, next we investigated the role of inflammasome activation and pyroptosis in the pathogenesis of TB-IRIS. HIV-TB patients exhibited higher proportions of monocytes expressing activated caspase 1 (casp1) pre-cART, compared to HIV patients without TB; patients who developed TB-IRIS exhibited increased casp1 levels following initiation of cART. TB-IRIS patients also had increased NLRP3 and AIM2 inflammasome mRNA, compared to controls. Expression of cell death markers (7-AAD and Annexin V by PBMC and plasma mitochondrial DNA (mtDNA) levels) was also higher in TB-IRIS patients. Plasma nitric oxide (NO) levels were lower precART in TB-IRIS patients suggest inadequate inflammasome regulation. Expression of IL-18Rα on CD4+ T cells and NK cells was higher in TB-IRIS patients post cART, providing evidence that receptiveness against IL-18 further increase inflammasome activation and pyroptosis in monocytes

Low SARS-CoV-2 viral load among vaccinated individuals infected with Delta B.1.617.2 and Omicron BA.1.1.529 but not with Omicron BA.1.1 and BA.2 variants

The rapid spread of SARS-CoV-2 variants in the global population is indicative of the development of selective advantages in emerging virus strains. Here, we performed a case-control investigation of the clinical and demographic characteristics, clinical history, and virological markers to predict disease progression in hospitalized adults for COVID-19 between December 2021 and January 2022 in Chennai, India. COVID-19 diagnosis was made by a commercial TaqPath COVID-19 RT-PCR, and WGS was performed with the Ion Torrent Next Generation Sequencing System. High-quality (<5% of N) complete sequences of 73 Omicron B.1.1.529 variants were randomly selected for phylogenetic analysis. SARS-CoV-2 viral load, number of comorbidities, and severe disease presentation were independently associated with a shorter time-to-death. Strikingly, this was observed among individuals infected with Omicron BA.2 but not among those with the BA.1.1.529, BA.1.1, or the Delta B.1.617.2 variants. Phylogenetic analysis revealed severe cases predominantly clustering under the BA.2 lineage. Sequence analyses showed 30 mutation sites in BA.1.1.529 and 33 in BA.1.1. The mutations unique to BA.2 were T19I, L24S, P25del, P26del, A27S, V213G, T376A, D405N and R408S. Low SARS-CoV-2 viral load among vaccinated individuals infected with Delta B.1.617.2 and the Omicron BA.1.1.529 variant but not with Omicron BA.1.1 or BA.2 suggests that the newer strains are largely immune escape variants. The number of vaccine doses received was independently associated with increased odds of developing asymptomatic disease or recovery. We propose that the novel mutations reported herein could likely bear a significant impact on the clinical characteristics, disease progression, and epidemiological aspects of COVID-19. Surging rates of mutations and the emergence of eclectic variants of SARS-CoV-2 appear to impact disease dynamics

Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome&mdash;An Extempore Game of Misfiring with Defense Arsenals

The lethal combination involving TB and HIV, known as &ldquo;syndemic&rdquo; diseases, synergistically act upon one another to magnify the disease burden. Individuals on anti-retroviral therapy (ART) are at risk of developing TB-associated immune reconstitution inflammatory syndrome (TB-IRIS). The underlying inflammatory complication includes the rapid restoration of immune responses following ART, eventually leading to exaggerated inflammatory responses to MTB antigens. TB-IRIS continues to be a cause of morbidity and mortality among HIV/TB coinfected patients initiating ART, and although a significant quantum of knowledge has been acquired on the pathogenesis of IRIS, the underlying pathomechanisms and identification of a sensitive and specific diagnostic marker still remain a grey area of investigation. Here, we reviewed the latest research developments into IRIS immunopathogenesis, and outlined the modalities to prevent and manage strategies for better clinical and diagnostic outcomes for IRIS

Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome-An Extempore Game of Misfiring with Defense Arsenals

The lethal combination involving TB and HIV, known as "syndemic" diseases, synergistically act upon one another to magnify the disease burden. Individuals on anti-retroviral therapy (ART) are at risk of developing TB-associated immune reconstitution inflammatory syndrome (TB-IRIS). The underlying inflammatory complication includes the rapid restoration of immune responses following ART, eventually leading to exaggerated inflammatory responses to MTB antigens. TB-IRIS continues to be a cause of morbidity and mortality among HIV/TB coinfected patients initiating ART, and although a significant quantum of knowledge has been acquired on the pathogenesis of IRIS, the underlying pathomechanisms and identification of a sensitive and specific diagnostic marker still remain a grey area of investigation. Here, we reviewed the latest research developments into IRIS immunopathogenesis, and outlined the modalities to prevent and manage strategies for better clinical and diagnostic outcomes for IRIS

Dengue Infection - Recent Advances in Disease Pathogenesis in the Era of COVID-19

The dynamics of host-virus interactions, and impairment of the hosts immune surveillance by dengue virus (DENV) serotypes largely remain ambiguous. Several experimental and preclinical studies have demonstrated how the virus brings about severe disease by activating immune cells and other key elements of the inflammatory cascade. Plasmablasts are activated during primary and secondary infections, and play a determinative role in severe dengue. The cross-reactivity of DENV immune responses with other flaviviruses can have implications both for cross-protection and severity of disease. The consequences of a cross-reactivity between DENV and anti-SARS-CoV-2 responses are highly relevant in endemic areas. Here, we review the latest progress in the understanding of dengue immunopathogenesis and provide suggestions to the development of target strategies against dengue.Funding Agencies|Xiamen University Malaysia [XMUMRF/2018-C2/ILAB/0001, XMUMRF/2020-C5/ITCM/0003, XMURF/2018-C1/ENG/0005]; NIH [R01AI148377]; Emory University CFAR [P30 AI050409]; NIH Office of Research Infrastructure Programs [P51 OD011132, U42 OD011023]; Swedish International Development Cooperation Agency; SIDA SARC; Linkoeping University Hospital Research Fund; CALF; Swedish Society of Medicine [AI52731]; Department of Science and Technology-Science and Engineering Research Board, Government of India [CRG/2019/006096]</p

Mucosal-Associated Invariant T Cells: Diplomatic Front-Runners in the Fight against Hepatitis B Virus Infection

Mucosal-associated invariant T (MAIT) cells are a unique subset of innate-like T cells that bridge between innate and adaptive immunity. MALT cells act like a biliary firewall protecting the epithelial lining of the liver against pathogenic intruders. MAIT1 and MAIT17 subsets respond rapidly to pathogenic presence both in the liver as well as in the peripheral circulation. In addition to chronic hepatitis B virus (HBV) infection, MAIT cells also appear to serve as potential therapeutic targets in several other chronic ailments. Evidence indicates that MAIT cells have tissue repair functions also paving way for fibrotic changes during chronic HBV infection. Observations also suggest that HBV-hepatitis delta virus (HDV) co-infection disease progression is closely associated with loss of MAIT cells. Furthermore, reduction in the number of hepatic MAIT cells in patients with cirrhotic non-alcoholic fatty liver disease and HBV-associated primary liver cancer has also been reported. Given their concrete role against HBV disease progression, and has also become evident that the tumor microenvironment can cause functional impairment of MAIT cells. Here, we reviewed the protective and the pathological role of MAIT cells in chronic HBV infection and certain other related medical conditions based on the understanding that an optimal functioning of the MAIT cell arsenal is key to a "host-friendly" immune defense against HBV disease progression.Funding Agencies|Xiamen University Malaysia Research Funding (XMUMRF) [XMUMRF/2020-C5/ITCM/0003, XMUMRF/2018-C2/ILAB/0001]; Department of Science and Technology-Science and Engineering Research Board, Government of India [CRG/2019/006096]; Swedish Research Council [AI52731]; Swedish Physicians against AIDS Research Foundation; Swedish International Development Cooperation Agency; SIDA SARC; VINNMER for Vinnova; Linkoping University Hospital Research Fund; Swedish Society of Medicine; CALF</p

Factors Associated With the Decay of Anti-SARS-CoV-2 S1 IgG Antibodies Among Recipients of an Adenoviral Vector-Based AZD1222 and a Whole-Virion Inactivated BBV152 Vaccine

BackgroundThe magnitude of protection conferred following recovery from COVID-19 or by vaccine administration, and the duration of protective immunity developed, remains ambiguous. MethodsWe investigated the factors associated with anti-SARS-CoV-2 S1 IgG decay in 519 individuals who recovered from COVID-19 illness or received COVID-19 vaccination with two commercial vaccines, viz., an adenoviral vector-based (AZD1222) and a whole-virion-based inactivated (BBV152) vaccine in Chennai, India from March to December 2021. Blood samples collected during regular follow-up post-infection/-vaccination were examined for anti-SARS-CoV-2 S1 IgG by a commercial automated chemiluminescent immunoassay (CLIA). ResultsAge and underlying comorbidities were the two variables that were independently associated with the development of a breakthrough infection. Individuals who were &amp;gt;60 years of age with underlying comorbid conditions (viz., hypertension, diabetes mellitus and cardiovascular disease) had a ~15 times and ~10 times greater odds for developing a breakthrough infection and hospitalization, respectively. The time elapsed since the first booster dose was associated with attrition in anti-SARS-CoV-2 IgG, where each month passed was associated with an ebb in the anti-SARS-CoV-2 IgG antibody levels by a coefficient of -6 units. ConclusionsOur findings advocate that the elderly with underlying comorbidities be administered with appropriate number of booster doses with AZD1222 and BBV152 against COVID-19