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1.
Ann Acad Med Singap ; 53(6): 361-370, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38979992

ABSTRACT

Introduction: This study aimed to evaluate the prevalence of developmental and emotional/ behavioural concerns in maltreated children and to examine the impact of adverse family/caregiver risk factors on these outcomes. Method: We analysed family demographic and baseline data of 132 maltreated children and their caregivers from a family support programme in Singapore. We examined the associations of 3 main risk factors (i.e., caregiver mental health, educational attainment, and family socio-economic status [SES]) with developmental/behavioural outcomes using multivariable logistic regression, controlling for caregiver relationship to the child. Caregiver mental health was assessed using the Patient Health Questionnaire 9 (PHQ-9) and General Anxiety Disorder 7 (GAD-7) tools. Developmental/behavioural outcomes were assessed using the Ages and Stages Questionnaires (ASQ-3), ASQ-Social-Emotional (ASQ-SE), and the Child Behaviour Checklist (CBCL). Results: The children ranged in age, from 2 months to 3 years 11 months (median age 1.7 years, interquartile range [IQR] 0.9-2.6). Among caregivers, 86 (65.2%) were biological mothers, 11 (8.3%) were biological fathers, and 35 (26.5%) were foster parents or extended family members. Low family SES was associated with communication concerns on the ASQ-3 (adjusted odds ratio [AOR] 3.04, 95% CI 1.08-8.57, P=0.04). Caregiver mental health concerns were associated with increased behavioural concerns on the CBCL (AOR 6.54, 95% CI 1.83-23.33, P=0.004) and higher scores on the ASQ-SE (AOR 7.78, 95% CI 2.38-25.38, P=0.001). Conclusion: Maltreated children with caregivers experiencing mental health issues are more likely to have heightened emotional and behavioural concerns. Those from low SES families are also at increased risk of language delay, affecting their communication.


Subject(s)
Caregivers , Child Abuse , Humans , Child, Preschool , Caregivers/psychology , Male , Female , Singapore/epidemiology , Risk Factors , Child Abuse/psychology , Child Abuse/statistics & numerical data , Infant , Educational Status , Mental Health , Child Behavior Disorders/epidemiology , Child Behavior Disorders/etiology , Surveys and Questionnaires , Family/psychology , Child Development , Child Behavior/psychology , Social Class
2.
Stem Cell Res Ther ; 14(1): 259, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37726837

ABSTRACT

BACKGROUND: Mesenchymal stromal cells (MSCs) have broad potential as a cell therapy including for the treatment of drug-resistant inflammatory conditions with abnormal T cell proliferation such as graft-versus-host disease (GVHD). Clinical success, however, has been complicated by the heterogeneity of culture-expanded MSCs as well as donor variability. Here, we devise culture conditions that promote expansion of MSCs with enhanced immunomodulatory functions both in vitro and in animal models of GVHD. METHODS: Human bone marrow-derived MSCs were expanded at high-confluency (MSCHC) and low-confluency state (MSCLC). Their immunomodulatory properties were evaluated with in vitro co-culture assays based on suppression of activated T cell proliferation and secretion of pro-inflammatory cytokines from activated T cells. Metabolic state of these cells was determined, while RNA sequencing was performed to explore transcriptome of these MSCs. Ex vivo expanded MSCHC or MSCLC was injected into human peripheral blood mononuclear cells (PBMC)-induced GVHD mouse model to determine their in vivo therapeutic efficacy based on clinical grade scoring, human CD45+ blood count and histopathological examination. RESULTS: As compared to MSCLC, MSCHC significantly reduced both the proliferation of anti-CD3/CD28-activated T cells and secretion of pro-inflammatory cytokines upon MSCHC co-culture across several donors even in the absence of cytokine priming. Mechanistically, metabolic analysis of MSCHC prior to co-culture with activated T cells showed increased glycolytic metabolism and lactate secretion compared to MSCLC, consistent with their ability to inhibit T cell proliferation. Transcriptome analysis further revealed differential expression of immunomodulatory genes including TRIM29, BPIFB4, MMP3 and SPP1 in MSCHC as well as enriched pathways including cytokine-cytokine receptor interactions, cell adhesion and PI3K-AKT signalling. Lastly, we demonstrate in a human PBMC-induced GVHD mouse model that delivery of MSCHC showed greater suppression of inflammation and improved outcomes compared to MSCLC and saline controls. CONCLUSION: Our study provides evidence that ex vivo expansion of MSCs at high confluency alters the metabolic and transcriptomic states of these cells. Importantly, this approach maximizes the production of MSCs with enhanced immunomodulatory functions without priming, thus providing a non-invasive and generalizable strategy for improving the use of MSCs for the treatment of inflammatory diseases.


Subject(s)
Leukocytes, Mononuclear , Mesenchymal Stem Cells , Animals , Mice , Humans , Bone Marrow , Phosphatidylinositol 3-Kinases , Cytokines , Disease Models, Animal , DNA-Binding Proteins , Transcription Factors , Intercellular Signaling Peptides and Proteins
3.
Asian J Psychiatr ; 81: 103457, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36638754

ABSTRACT

OBJECTIVE: To study the effectiveness of the Sure Mums intervention in improving mother-baby bonding in a group of new mothers in Singapore. METHODS: Over a period of 2 years from 2017 to 2019, thirty-two mothers were identified from our clinic population seeking treatment for postnatal mental health difficulties - these included depressive or anxiety symptoms, together with bonding difficulties. They received home-based mother-infant therapy sessions, and scores for the Postpartum Bonding Questionnaire (PBQ), Global Assessment of Functioning (GAF), and Edinburgh Postnatal Depression Scale (EPDS) were taken pre- and post-intervention. RESULTS: In all, twenty-five mothers completed measures for baseline characteristics, pretreatment scores and post-treatment scores. Paired sample t-tests were conducted for the 4 subscales of the PBQ, the GAF rating score, and the EPDS score. Postintervention scores noted a reduction in the mean of all of the 4 PBQ subscales, and 3 of the 4 scores had differences that were shown to be statistically significant improvement. The EPDS pre-intervention mean score was 17.72, while mean postintervention EPDS score was 9.2. Total GAF scores showed an mean uptrend by 12-14 points, likely indicating significant improvement in the mothers' functioning post intervention. CONCLUSIONS: The results of this programme shows promising evidence of its effectiveness in improving the quality of bonding in mothers with postnatal mental health difficulties. For future direction, we hope to offer the SURE MUMS programme to more mothers who are struggling to bond with their baby amidst the challenges of becoming a parent.


Subject(s)
Depression, Postpartum , Female , Infant , Humans , Depression, Postpartum/epidemiology , Mothers/psychology , Mother-Child Relations , Postpartum Period , Anxiety/epidemiology , Object Attachment
4.
Ann Acad Med Singap ; 52(6): 296-309, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-38904511

ABSTRACT

Introduction: This study evaluates the effectiveness of a hospital-based return to work (RTW) programme in facilitating injured workers to RTW earlier through personalised case management. Factors associated with programme effectiveness are also examined. Method: This was a quasi-experimental study comparing 81 participants who underwent conventional treatment before the RTW programme with 108 participants who directly received the RTW intervention. Analyses included time to RTW and the factors associated with dropout. Stratified analysis and multivariate logistic regression were used to mitigate potential selection bias from the additional recruitment process for the intervention group. Results: Participants in the intervention group returned to work 59.5 days earlier, with 84% able to RTW 6 months post injury compared with the control (63%; P<0.01). Stratified analysis found the intervention to be associated with better RTW outcomes among males, younger workers, non-residents, blue-collared workers, workers from the construction, marine, manufacturing and metalworking industries, and workers having lower Work Ability score (WAS), while light-duty provision was a possible confounder. The better outcomes in the intervention group were also independent of company size and injury severity. After adjusting for the above factors, the intervention group had 2.2 times higher odds of RTW at 6 months (95% confidence interval 0.84–5.90). Lower WAS and longer delay in initial RTW assessment were associated with delayed RTW within the intervention group. Migrant workers experienced higher dropout rates, thus being identified as a vulnerable group. Conclusion: The RTW coordination model of care is effective in facilitating RTW, with early programme referral being an important facilitator and WAS as a useful screening tool for delayed RTW.


Subject(s)
Hospitals, Public , Occupational Injuries , Return to Work , Humans , Return to Work/statistics & numerical data , Singapore , Male , Adult , Occupational Injuries/rehabilitation , Female , Middle Aged , Program Evaluation , Case Management/organization & administration , Time Factors , Logistic Models
5.
Sci Rep ; 12(1): 16257, 2022 09 28.
Article in English | MEDLINE | ID: mdl-36171219

ABSTRACT

Our study sought to examine the impact of the pandemic and the Circuit-breaker (CB) measures on dietary behaviours of healthcare workers (HCW). In addition, the association between self-regulatory eating behaviours and psychological stress was explored. Our study employed a cross-sectional anonymous survey that examined the demographics, dietary habits, self-regulatory eating behaviours (SR) and their association to stress levels of healthcare workers (HCWs) before and during the Circuit Breaker (CB) in Singapore. The survey was conducted over four weeks from May 17 to June 18, 2020. Snowball sampling was performed in the final week. A total of 707 participants took part in the survey. Due to the CB measures and modifications of work scope and work areas, there were significant changes in their dietary behaviors before CB versus during the CB period (n = 707), with many reducing the intake of vegetables (p = 0.018) while increasing their intake of unhealthy food choices such as canned drinks (p = 0.002), convenience food (p ≤ 0.001) and alcoholic drinks (p = 0.034). Before the CB period, 91.8% (602/656) of participants who intended to have a healthy diet were classified in medium-to-high SR groups whereas during the CB period, 87.7% (575/656) were in medium-to-high SR groups and the difference was statistically significant (p = 0.011). Nurses, administrative staff, HCWs of Chinese and Indian ethnicities, staff who did not complete university education and those who did not have domestic helpers were more likely to have reduced SR. Importantly, amongst participants who intended to have a healthy diet, 70.9% displayed no change or improved eating habits and showed medium-to-high levels of SR during CB. Participants with no changes in SR were 2.11 times more likely to be stress-free as compared to those who had deteriorated SR (OR 2.11 95% CI 1.27-3.48, p = 0.004). Due to CB measures and work modifications, dietary behaviours of HCWs deteriorated with increased intake of unhealthy food choices. HCWs who maintain their self-regulatory eating behaviour are more likely to be stress-free. Short screening questionnaires based on SR changes should be developed and explored as surveillance tools for assessment of HCWs' general well-being such that personalized interventions to vulnerable groups of workers could be implemented effectively on the ground.


Subject(s)
COVID-19 , COVID-19/epidemiology , Communicable Disease Control , Cross-Sectional Studies , Feeding Behavior , Health Personnel , Humans , Singapore/epidemiology
6.
Pharmaceuticals (Basel) ; 15(9)2022 Sep 07.
Article in English | MEDLINE | ID: mdl-36145337

ABSTRACT

The emergence of virulent extended spectrum ß-lactamase producing Klebsiella pneumoniae (ESBL-KP) including carbapenem-resistant Klebsiella pneumoniae (CRKP) in hospital-acquired infections has resulted in significant morbidity and mortality worldwide. We investigated the antibiotic resistance and virulence factors associated with ESBL-KP and CRKP in tertiary care hospitals in Bangladesh and explored their ability to form biofilm. A total of 67 ESBL-KP were isolated from 285 Klebsiella pneumoniae isolates from environmental and patient samples from January 2019 to April 2019. For ESBL-KP isolates, molecular typing was carried out using enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR), antibiotic susceptibility testing, PCR for virulence and drug-resistant genes, and biofilm assays were also performed. All 67 isolates were multidrug-resistant (MDR) to different antibiotics at high levels and 42 isolates were also carbapenem-resistant. The most common ß-lactam resistance gene was blaCTX-M-1 (91%), followed by blaTEM (76.1%), blaSHV (68.7%), blaOXA-1 (29.9%), blaGES (14.9%), blaCTX-M-9 (11.9%), and blaCTX-M-2 (4.5%). The carbapenemase genes blaKPC (55.2%), blaIMP (28.4%), blaVIM (14.9%), blaNDM-1 (13.4%), and blaOXA-48 (10.4%) and virulence-associated genes such as fimH (71.6%), ugeF (58.2%), wabG (56.7%), ureA (47.8%) and kfuBC (28.4%) were also detected. About 96.2% of the environmental and 100% of the patient isolates were able to form biofilms. ERIC-PCR-based genotyping and hierarchical clustering of K. pneumoniae isolates revealed an association between environmental and patient samples, indicating clonal association with possible transmission of antimicrobial resistance genes. Our findings can help in improving patient care and infection control, and the development of public health policies related to hospital-acquired infections.

7.
J Allergy Clin Immunol ; 150(6): 1415-1426.e9, 2022 12.
Article in English | MEDLINE | ID: mdl-35917932

ABSTRACT

BACKGROUND: Patients with asthma often suffer from frequent respiratory viral infections and reduced virus clearance. Lung resident memory T cells provide rapid protection against viral reinfections. OBJECTIVE: Because the development of resident memory T cells relies on the lung microenvironment, we investigated the impact of allergen sensitization on the development of virus-specific lung resident memory T cells and viral clearance. METHODS: Mice were sensitized with house dust mite extract followed by priming with X47 and a subsequent secondary influenza infection. Antiviral memory T-cell response and protection to viral infection was assessed before and after secondary influenza infection, respectively. Gene set variation analysis was performed on data sets from the U-BIOPRED asthma cohort using an IFN-γ-induced epithelial cell signature and a tissue resident memory T-cell signature. RESULTS: Viral loads were higher in lungs of sensitized compared with nonsensitized mice after secondary infection, indicating reduced virus clearance. X47 priming induced fewer antiviral lung resident memory CD8 T cells and resulted in lower pulmonary IFN-γ levels in the lungs of sensitized as compared with nonsensitized mice. Using data from the U-BIOPRED cohort, we found that patients with enrichment of epithelial IFN-γ-induced genes in nasal brushings and bronchial biopsies were also enriched in resident memory T-cell-associated genes, had more epithelial CD8 T cells, and reported significantly fewer exacerbations. CONCLUSIONS: The allergen-sensitized lung microenvironment interferes with the formation of antiviral resident memory CD8 T cells in lungs and virus clearance. Defective antiviral memory response might contribute to increased susceptibility of patients with asthma to viral exacerbations.


Subject(s)
Influenza, Human , Memory T Cells , Mice , Animals , Humans , Lung , CD8-Positive T-Lymphocytes , Allergens
8.
Proc Natl Acad Sci U S A ; 119(31): e2201376119, 2022 08 02.
Article in English | MEDLINE | ID: mdl-35878022

ABSTRACT

Relapse to anti-HER2 monoclonal antibody (mAb) therapies, such as trastuzumab in HER2+ breast cancer (BC), is associated with residual disease progression due to resistance to therapy. Here, we identify interferon-γ inducible protein 16 (IFI16)-dependent STING signaling as a significant determinant of trastuzumab responses in HER2+ BC. We show that down-regulation of immune-regulated genes (IRG) is specifically associated with poor survival of HER2+, but not other BC subtypes. Among IRG, IFI16 is identified as a direct target of EZH2, the underexpression of which leads to deficient STING activation and downstream CXCL10/11 expression in response to trastuzumab treatment. Dual inhibition of EZH2 and histone deacetylase (HDAC) significantly activates IFI16-dependent immune responses to trastuzumab. Notably, a combination of a novel histone methylation inhibitor with an HDAC inhibitor induces complete tumor eradication and long-term T cell memory in a HER2+ BC mouse model. Our findings demonstrate an epigenetic regulatory mechanism suppressing the expression of the IFI16-CXCL10/11 signaling pathway that provides a survival advantage to HER2+ BC to confer resistance to trastuzumab treatment.


Subject(s)
Breast Neoplasms , Drug Resistance, Neoplasm , Membrane Proteins , Nuclear Proteins , Phosphoproteins , Trastuzumab , Animals , Antineoplastic Agents, Immunological/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/immunology , Cell Line, Tumor , Chemokine CXCL10 , Chemokine CXCL11 , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Humans , Immunity , Membrane Proteins/metabolism , Mice , Neoplasm Recurrence, Local/genetics , Nuclear Proteins/metabolism , Phosphoproteins/metabolism , Receptor, ErbB-2/genetics , Signal Transduction , Trastuzumab/pharmacology
9.
Nat Commun ; 13(1): 4118, 2022 07 15.
Article in English | MEDLINE | ID: mdl-35840558

ABSTRACT

The hypoxic tumor microenvironment has been implicated in immune escape, but the underlying mechanism remains elusive. Using an in vitro culture system modeling human T cell dysfunction and exhaustion in triple-negative breast cancer (TNBC), we find that hypoxia suppresses immune effector gene expression, including in T and NK cells, resulting in immune effector cell dysfunction and resistance to immunotherapy. We demonstrate that hypoxia-induced factor 1α (HIF1α) interaction with HDAC1 and concurrent PRC2 dependency causes chromatin remolding resulting in epigenetic suppression of effector genes and subsequent immune dysfunction. Targeting HIF1α and the associated epigenetic machinery can reverse the immune effector dysfunction and overcome resistance to PD-1 blockade, as demonstrated both in vitro and in vivo using syngeneic and humanized mice models. These findings identify a HIF1α-mediated epigenetic mechanism in immune dysfunction and provide a potential strategy to overcome immune resistance in TNBC.


Subject(s)
Triple Negative Breast Neoplasms , Animals , Cell Line, Tumor , Epigenesis, Genetic , Humans , Hypoxia/genetics , Immunotherapy/methods , Mice , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/therapy , Tumor Microenvironment/genetics
10.
IJID Reg ; 2: 63-69, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35721419

ABSTRACT

Objective: To describe the clinical and epidemiological characteristics of children diagnosed with coronavirus disease 2019 (COVID-19) at Hospital Sungai Buloh, Selangor, Malaysia. Methods: A retrospective observational study was performed on children aged <12 years diagnosed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection between January 25 and December 31, 2020. A comparative analysis was undertaken between asymptomatic and symptomatic children, as well as a sub-analysis of their caretakers' COVID-19 status. Results: A total of 1498 children were included, 48.7% female and 51.3% male. Their mean age was 5.6 years (standard deviation 3.5 years). Overall, 82.3% were detected through contact tracing of positive family members or from the same household. Fifty-seven percent were asymptomatic. The most common symptoms reported were fever, nasal congestion/rhinorrhoea, and cough. Compared to asymptomatic children, those who were symptomatic had higher reported comorbidities, lower total white blood cell (WBC), absolute lymphocyte, and absolute neutrophil counts, raised C-reactive protein (CRP), and raised aspartate transaminase (P < 0.05). The median duration of illness was 10 days (interquartile range 3 days). Overall outcomes were good. Only 19 (8.2%) negative caretakers seroconverted prior to discharge. Conclusions: The majority of the children in the State of Selangor experienced mild COVID-19 illness in 2020, and they did not appear to be key drivers in the transmission of the disease.

11.
Curr Opin Environ Sci Health ; 27: 100334, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35434440

ABSTRACT

The ongoing pandemic of the coronavirus disease 2019 (COVID-19) is a public health crisis of global concern. The progression of the COVID-19 pandemic has been monitored in the first place by testing symptomatic individuals for SARS-CoV-2 virus in the respiratory samples. Concurrently, wastewater carries feces, urine, and sputum that potentially contains SARS-CoV-2 intact virus or partially damaged viral genetic materials excreted by infected individuals. This brings significant opportunities for understanding the infection dynamics by environmental surveillance. It has advantages for the country, especially in densely populated areas where individual clinical testing is difficult. However, there are several challenges including: 1) establishing a sampling plan and schedule that is representative of the various catchment populations 2) development and validation of standardized protocols for the laboratory analysis 3) understanding hydraulic flows and virus transport in complex wastewater drainage systems and 4) collaborative efforts from government agencies, NGOs, public health units and academia.

12.
Mucosal Immunol ; 15(4): 717-729, 2022 04.
Article in English | MEDLINE | ID: mdl-35260804

ABSTRACT

The fate of tissue-resident memory CD4 T cells (Trm) has been incompletely investigated. Here we show that intranasal, but not parenteral, immunization with CTA1-3M2e-DD stimulated M2e-specific Th17 Trm cells, which conferred strong protection against influenza virus infection in the lung. These cells rapidly expanded upon infection and effectively restricted virus replication as determined by CD4 T cell depletion studies. Single-cell RNAseq transcriptomic and TCR VDJ-analysis of M2e-tetramer-sorted CD4 T cells on day 3 and 8 post infection revealed complete Th17-lineage dominance (no Th1 or Tregs) with extensive functional diversity and expression of gene markers signifying mature resident Trm cells (Cd69, Nfkbid, Brd2, FosB). Unexpectedly, the same TCR clonotype hosted cells with different Th17 subcluster functions (IL-17, IL-22), regulatory and cytotoxic cells, suggesting a tissue and context-dependent differentiation of reactivated Th17 Trm cells. A gene set enrichment analysis demonstrated up-regulation of regulatory genes (Lag3, Tigit, Ctla4, Pdcd1) in M2e-specific Trm cells on day 8, indicating a tissue damage preventing function. Thus, contrary to current thinking, lung M2e-specific Th17 Trm cells are sufficient for controlling infection and for protecting against tissue injury. These findings will have strong implications for vaccine development against respiratory virus infections and influenza virus infections, in particular.


Subject(s)
Influenza Vaccines , Influenza, Human , Orthomyxoviridae Infections , Humans , Immunologic Memory , Lung , Receptors, Antigen, T-Cell , Th17 Cells
13.
Heliyon ; 8(3): e09045, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35287328

ABSTRACT

The synthesized 3,3-di(indolyl)indolin-2-ones 1a-p showed desired higher α-glucosidase inhibitory activities and lower α-amylase inhibitory activities than standard drug acarbose. Particularly, compound 1i showed favorable higher α-glucosidase % inhibition of 67 ± 13 and lower α-amylase % inhibition of 51 ± 4 in comparison to acarbose with % inhibition activities of 19 ± 5 and 90 ± 2, respectively. Docking studies of selected 3,3-di(indolyl)indolin-2-ones revealed key interactions with the active sites of both α-glucosidase and α-amylase, further supporting the observed % inhibitory activities. Furthermore, the binding energies are consistent with the % inhibition values. The results suggest that 3,3-di(indolyl)indolin-2-ones may be developed as suitable Alpha Glucosidase Inhibitors (AGIs) and the lower α-amylase activities should be advantageous to reduce the side effects exhibited by commercial AGIs.

14.
Molecules ; 27(2)2022 Jan 15.
Article in English | MEDLINE | ID: mdl-35056850

ABSTRACT

In this study, we report on an orthogonal strategy for the precise synthesis of 3,3'-, 3,4'-, and 3,6'-phenylpropanoid sucrose esters (PSEs). The strategy relies on carefully selected protecting groups and deprotecting agents, taking into consideration the reactivity of the four free hydroxyl groups of the key starting material: di-isopropylidene sucrose 2. The synthetic strategy is general, and potentially applies to the preparation of many natural and unnatural PSEs, especially those substituted at 3-, 3'-, 4'- and 6'-positions of PSEs.

15.
Curr Med Chem ; 29(9): 1606-1621, 2022.
Article in English | MEDLINE | ID: mdl-34455958

ABSTRACT

INTRODUCTION: Feruloyl Sucrose Esters (FSEs) are a class of Phenylpropanoid Sucrose Esters (PSEs) widely distributed in plants. They were investigated as potential selective Alpha Glucosidase Inhibitors (AGIs) to eliminate the side effects associated with the current commercial AGIs. The latter effectively lowers blood glucose levels in diabetic patients but causes severe gastrointestinal side effects. METHODS: Systematic structure-activity relationship (SAR) studies using in silico, in vitro and in vivo experiments were used to accomplish this aim. FSEs were evaluated for their in vitro inhibition of starch and oligosaccharide digesting enzymes α-glucosidase and α- amylase followed by in silico docking studies to identify the binding modes. A lead candidate, FSE 12 was investigated in an STZ mouse model. RESULTS: All active FSEs showed desired higher % inhibition of α-glucosidase and desired lower inhibition of α -amylase in comparison to AGI gold standard acarbose. This suggests a greater selectivity of the FSEs towards α -glucosidase than α -amylase, which is proposed to eliminate the gastrointestinal side effects. From the in vitro studies, the position and number of the feruloyl substituents on the sucrose core, the aromatic 'OH' group, and the diisopropylidene bridges were key determinants of the % inhibition of α - glucosidase and α -amylase. In particular, the diisopropylidene bridges are critical for achieving inhibition selectivity. Molecular docking studies of the FSEs corroborates the in vitro results. The molecular docking studies further reveal that the presence of free aromatic 'OH' groups and the substitution at position 3 on the sucrose core are critical for the inhibition of both the enzymes. From the in vitro and molecular docking studies, FSE 12 was selected as a lead candidate for validation in vivo. The oral co-administration of FSE 12 with starch abrogated the increase in post-prandial glucose and significantly reduced blood glucose excursion in STZ-treated mice compared to control (starch only) mice. CONCLUSION: Our studies reveal the potential of FSEs as selective AGIs for the treatment of diabetes, with a hypothetical reduction of side effects associated with commercial AGIs.


Subject(s)
Diabetes Mellitus , alpha-Glucosidases , Animals , Blood Glucose/metabolism , Diabetes Mellitus/drug therapy , Esters/pharmacology , Esters/therapeutic use , Glycoside Hydrolase Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/pharmacology , Humans , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Mice , Molecular Docking Simulation , Starch/therapeutic use , Sucrose/therapeutic use , alpha-Amylases/chemistry , alpha-Amylases/metabolism , alpha-Glucosidases/metabolism
16.
Stress Health ; 38(1): 171-179, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34231968

ABSTRACT

The outbreak of COVID-19 has precipitated international lockdown measures to curb disease transmissions. The closure of public activity spaces as well as changes in pandemic workload may disrupt healthcare workers' physical activity and self-care routines. We sought to examine the association between physical activity levels and mental health burden of healthcare workers during the COVID-19 lockdown in Singapore. This cross-sectional study comprised of an multidomain survey that was administered digitally to 707 healthcare workers between 17 May and 18 June 2020. Exercise frequency, duration and intensity of these healthcare workers had reduced significantly during the lockdown compared to pre-lockdown. 25.3%, 37.2%, and 11.9% had screened positive for moderate-to-extremely-severe depression, anxiety and stress respectively. Reductions in exercise duration was a significant risk factor for mild stress and moderate-to-severe depression while increase in exercise frequency was found to be a protective factor against depressed mood. Our study revealed that a short-term reduction in physical activity levels during lockdown was associated with poorer psychological outcomes. Given the protection that exercise confers on depression, physical activity should be promoted at the workplace and at home to support healthcare workers to cope through this protracted health crisis.


Subject(s)
COVID-19 , Mental Health , Anxiety , Communicable Disease Control , Cross-Sectional Studies , Depression/epidemiology , Exercise , Health Personnel , Humans , SARS-CoV-2
17.
Front Immunol ; 12: 749325, 2021.
Article in English | MEDLINE | ID: mdl-34659250

ABSTRACT

Previous work showed that interferon-λ (IFN-λ) can trigger the synthesis of thymic stromal lymphopoietin (TSLP) by specialized epithelial cells in the upper airways of mice, thereby improving the performance of intranasally administered influenza vaccines. Here we demonstrate that protein-only influenza vaccines containing either IFN-λ or TSLP boosted antigen-specific IgG1 and IgA responses and enhanced the resistance of mice to influenza virus challenge, irrespective of whether the vaccines were applied via the intranasal or the rectal route. TSLP receptor deficiency negatively influenced vaccine-induced antiviral immunity by impairing the migration of dendritic cells from the airways to the draining lymph nodes of immunized mice, thereby restraining follicular helper T cell and germinal center B cell responses. As previously observed during intranasal vaccination, the adjuvant effect of IFN-λ on a rectally administered influenza vaccine was no longer observed when TSLP receptor-deficient mice were used for immunization, highlighting the central role of the IFN-λ/TSLP axis for vaccine-induced antiviral immunity in the mucosa.


Subject(s)
Cytokines/administration & dosage , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Influenza Vaccines/administration & dosage , Interferons/administration & dosage , Orthomyxoviridae Infections/prevention & control , Vaccines, Subunit/administration & dosage , Administration, Intranasal , Administration, Rectal , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , Bronchoalveolar Lavage Fluid/immunology , Female , Immunoglobulins/genetics , Influenza A virus , Lymph Nodes/cytology , Lymph Nodes/immunology , Mice, Inbred C57BL , Mice, Knockout , Receptors, Cytokine/genetics , Thymic Stromal Lymphopoietin
18.
Biochim Biophys Acta Gen Subj ; 1865(12): 130005, 2021 12.
Article in English | MEDLINE | ID: mdl-34509570

ABSTRACT

BACKGROUND: Cytoskeletal protein filamin A is critical for the outside-in signaling of integrins. Although molecular mechanisms of filamin-integrin interactions are not fully understood. Mostly, the membrane distal (MD) part of the cytosolic tail (CT) of ß subunit of integrin is known to interact with filamin A domain 21 (FLNa-Ig2). However, binary and ternary complexes of full-length CTs of leucocyte specific ß2 integrins with FLNa-Ig21 are yet to be elucidated. METHODS: Binding interactions of the CTs of integrin αMß2 with FLNa-Ig21 are extensively investigated by NMR, ITC, cell-based functional assays and computational docking. RESULTS: The αM CT demonstrates interactions with FLNa-Ig21 forming a binary complex. Filamin/αM interface is mediated by sidechain-sidechain interactions among non-polar and aromatic residues involving MP helix of αM and the canonical CD face of FLNa-Ig21. Functional assays delineated an interfacial residue Y1137 of αM CT is critical for in-cell binding to FLNa-Ig2. In addition, full-length ß2 CT occupies two distinct binding sites in complex with FLNa-Ig21. A ternary complex of FLNa-Ig21 with CTs has been characterized. In the ternary complex, αM CT moves away to a distal site of FLNa-Ig21 with fewer interactions. CONCLUSION: Our findings demonstrate a plausible dual role of filamin in integrin regulation. The molecular interactions of the ternary complex are critical for the resting state of integrins whereas stable FLNa-Ig21/αM CT binary complex perhaps be required for the activated state. GENERAL SIGNIFICANCE: Filamin binding to both α and ß CTs of other integrins could be essential in regulating bidirectional signaling mechanisms.


Subject(s)
Cytosol , Cell Communication , Filamins
19.
Acta Oncol ; 60(10): 1291-1295, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34259123

ABSTRACT

OBJECTIVE: To report the long-term clinical outcomes of low-risk (LR) and intermediate-risk (IR) prostate cancer patients treated with low-dose-rate brachytherapy (LDR-BT) and external beam radiation therapy (EBRT). PATIENTS AND METHODS: Men with biopsy-proven low- and intermediate-risk prostate cancer received EBRT and LDR-BT in an Asian academic center from 2000 to 2019 were reviewed. Kaplan-Meier survival analysis was performed to compare biochemical failure-free survival (bFFS) and overall survival (OS) between LDR and EBRT in the low- and intermediate-risk cohorts. RESULTS: 642 patients (521 EBRT and 121 LDR-BT) with low- and intermediate-risk prostate cancer were included for analysis. In the intermediate-risk group, 5- and 10-year bFFS was 96%, 89% and 86%, 61% for LDR-BT and EBRT, respectively. LDR-BT was associated with a statistically significant improvement of bFFS in the intermediate-risk cohort (HR 2.7, p = 0.02). In the low-risk cohort, no difference of bFFS was found between LDR-BT and EBRT (HR 1.9, p = 0.08). Hormone therapy was more common in EBRT than LDR-BT for intermediate-risk group (71% versus 44%, p < 0.05). Prostate cancer-specific mortality was low in both EBRT (1%) and LDR-BT (2%) cohorts. No significant difference in OS was found between LDR-BT and EBRT in low- and intermediate-risk group (HR 2.1, p = 0.2 and HR = 1.7, p = 0.3). CONCLUSION: In our retrospective study, LDR-BT is associated with superior bFFS compared with EBRT in Asian men with intermediate-risk prostate cancer.


Subject(s)
Brachytherapy , Prostatic Neoplasms , Humans , Male , Prostatic Neoplasms/radiotherapy , Radiotherapy Dosage , Retrospective Studies , Risk Factors
20.
Int J Sports Med ; 42(13): 1143-1158, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34256388

ABSTRACT

Short-chain fatty acids (SCFAs) are metabolites produced in the gut via microbial fermentation of dietary fibers referred to as microbiota-accessible carbohydrates (MACs). Acetate, propionate, and butyrate have been observed to regulate host dietary nutrient metabolism, energy balance, and local and systemic immune functions. In vitro and in vivo experiments have shown links between the presence of bacteria-derived SCFAs and host health through the blunting of inflammatory processes, as well as purported protection from the development of illness associated with respiratory infections. This bank of evidence suggests that SCFAs could be beneficial to enhance the athlete's immunity, as well as act to improve exercise recovery via anti-inflammatory activity and to provide additional energy substrates for exercise performance. However, the mechanistic basis and applied evidence for these relationships in humans have yet to be fully established. In this narrative review, we explore the existing knowledge of SCFA synthesis and the functional importance of the gut microbiome composition to induce SCFA production. Further, changes in gut microbiota associated with exercise and various dietary MACs are described. Finally, we provide suggestions for future research and practical applications, including how these metabolites could be manipulated through dietary fiber intake to optimize immunity and energy metabolism.


Subject(s)
Athletes , Fatty Acids, Volatile/administration & dosage , Gastrointestinal Microbiome , Performance-Enhancing Substances/administration & dosage , Anti-Inflammatory Agents , Dietary Fiber , Exercise , Humans
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