THE GUT-BRAIN AXIS: IMPLICATIONS FOR NEUROLOGICAL DISORDERS, MENTAL HEALTH, AND IMMUNE FUNCTION

A gut-brain axis (GBA) has a long history of conceptual development. Intestinal dysbiosis has now been recognized as a key player in the development of adult neurodevelopmental disorders, obesity, and inflammatory bowel disease. Recent developments in metagenomics suggest those nutrition and gut microbiotas (GM) are important regulators of the gut-brain communication pathways that cause neurodevelopmental and psychiatric problems in adulthood. Intestinal dysbiosis and neurodevelopmental disease outcomes in preterm newborns are being linked by recent research. Recent clinical investigations demonstrate that in critical care units, intestinal dysbiosis occurs before late-onset newborn sepsis and necrotizing enterocolitis. Strong epidemiologic data also shows a connection between necrotizing enterocolitis and extremely low birth weight babies' long-term psychomotor impairments and late-onset neonatal sepsis. The GBA theory suggests that intestinal bacteria may indirectly affect preterm newborns' developing brains. In this review, we emphasize the structure and function of the GBA and discuss how immune-microbial dysfunction in the gut affects the transmission of stress signals to the brain. Preterm babies who are exposed to these signals develop neurologic disorders. Understanding neuronal and humoral communication through the GBA may provide insight into therapeutic and nutritional strategies that may enhance the results of very low-birth-weight babies.

RNA- and ATAC-sequencing Reveals a Unique CD83+ Microglial Population Focally Depleted in Parkinson's Disease

All brain areas affected in Parkinson's disease (PD) show an abundance of microglia with an activated morphology together with increased expression of pro-inflammatory cytokines, suggesting that neuroinflammation may contribute to the neurodegenerative process in this common and incurable disorder. We applied a single nucleus RNA- and ATAC-sequencing approach using the 10x Genomics Chromium platform to postmortem PD samples to investigate microglial heterogeneity in PD. We created a multiomic dataset using substantia nigra (SN) tissues from 19 PD donors and 14 non-PD controls (NPCs), as well as three other brain regions from the PD donors which are differentially affected in this disease: the ventral tegmental area (VTA), substantia inominata (SI), and hypothalamus (HypoTs). We identified thirteen microglial subpopulations within these tissues as well as a perivascular macrophage and a monocyte population, of which we characterized the transcriptional and chromatin repertoires. Using this data, we investigated whether these microglial subpopulations have any association with PD and whether they have regional specificity. We uncovered several changes in microglial subpopulations in PD, which appear to parallel the magnitude of neurodegeneration across these four selected brain regions. Specifically, we identified that inflammatory microglia in PD are more prevalent in the SN and differentially express PD-associated markers. Our analysis revealed the depletion of a CD83 and HIF1A- expressing microglial subpopulation, specifically in the SN in PD, that has a unique chromatin signature compared to other microglial subpopulations. Interestingly, this microglial subpopulation has regional specificity to the brainstem in non-disease tissues. Furthermore, it is highly enriched for transcripts of proteins involved in antigen presentation and heat-shock proteins, and its depletion in the PD SN may have implications for neuronal vulnerability in disease.

Influence of silylated nano cellulose reinforcement on the mechanical, water resistance, thermal, morphological and antibacterial properties of soy protein isolate (SPI)-based composite films

The aim of this research work is to improve the mechanical and water-resistance properties of soy protein isolate (SPI) biofilm. In this work, 3-aminopropyltriethoxysilane (APTES) coupling agent modified nanocellulose was introduced into the SPI matrix in the presence of citric acid cross-linker. The presence of amino groups in APTES facilitated to form cross-linked structures with soy protein. The incorporation of a citric acid cross-linker made the cross-linking process more productive, and the surface smoothness of the film was confirmed by a Scanning Electron Microscope (FE-SEM). From the study of the mechanical and thermal properties and water resistance of the film, it was confirmed that the results were highly satisfactory for the modified nanocellulose incorporated film compared to the non-modified one. Additionally, coating of citral essential oil onto SPI nanocomposite film displayed antimicrobial properties due to the presence of various phenolic groups in the citral oil. The Tensile Strength and Young's Modulus of silane-modified nanocellulose containing film were enhanced by ~119 % and ~ 112 %, respectively on incorporation of 1 % APTES-modified nanocellulose. Consequently, this work is expected to offer an effective way for silylated nano-cellulose reinforcing soy protein isolate (SPI) based bio nanocomposite films for packaging applications. As an example, we have demonstrated one of the application as wrapping films for packing black grapes.

Fibrocalculous Pancreatic Diabetes - a Unique Differential among Diabetic

Fibrocalculous pancreatic diabetes is a unique variant of diabetes mellitus and also known as type 3c diabetes mellitus. It is related to the patient who is young, non-alcoholic and belonging predominantly from the tropical region. It is a severe form of diabetes which can also be linked to the fact that it predisposes to malignancy.1 Among the variants of diabetes that we commonly encounter, fibrocalculous pancreatic diabetes has been rarely diagnosed in the developing countries. With the advancement of diagnostic capacity, it can be identified clinically and managed efficiently. It should be considered in patients with typical features of diabetes, abdominal pain, and pancreatic calculi. There is limited reporting of this case in Nepal because of misdiagnosis, so we are reporting a 40 years male who presented with recurrent episodes of abdominal pain with mucus mixed stool for the last 28 years and was diagnosed as fibrocalculous pancreatic diabetes. Keywords: Blood glucose; eastern Nepal; fibrocalculous pancreatic diabetes; pancreas.

Abstract P3-11-11: Impaired Succinate Metabolism Supports Endocrine Therapy Resistance in ER Positive Breast Cancers

Estrogen receptor positive (ER+) breast cancer is the most common subtype among all breast cancers and is responsible for most breast cancer related deaths. Endocrine therapies, such as selective estrogen receptor modulators (SERM) and aromatase inhibitors (AI), often given in combination with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, are initially effective but the majority of advanced ER+ breast cancers eventually become refractory to endocrine therapies. Therefore, understanding the underlying molecular mechanisms that enable or promote resistance to endocrine therapies may lead to novel therapeutic targets. Cancer cells consume greater quantities of glucose to meet their energy and anabolic demands to support cell growth and proliferation. In this study, we used breast cancer cell models that are endocrine therapy sensitive and resistant and investigated the metabolites by growing the cells in the presence of the stable glucose isotope, UC13-Glucose. We measured the C13-labelled metabolites of glycolysis and the TCA cycle. Glucose consumption was higher in endocrine therapy resistant MCF7/LCC9 (LCC9) cells compared with parental MCF7 (MCF7) and estrogen independent, endocrine therapy sensitive MCF7/LCC1 (LCC1) cells. Notably, in LCC9 cells the m+4 and m+6 isotopomer of C-13 labelled citrate was absent with a concurrent high succinate:fumarate ratio. Furthermore, in LCC9 cells, most of the fumarate was unlabeled suggesting that fumarate was not generated from glucose. These results suggest that the TCA cycle is impaired in LCC9 cells and the conversion of succinate to fumarate is dysregulated. Succinate dehydrogenase (SDH) enzyme is responsible for reversible catalytic conversion of succinate to fumarate. SDH is a multimeric protein comprised of four different subunits and SDH assembly factor 2 (SDHAF2), which is a tumor suppressor gene. Comparable SDH enzyme activity was observed in LCC9 and LCC1 cells. Intriguingly, when SDH activity was inhibited using dimethylmalonate, the LCC9 cells were re-sensitized to both Fulvestrant and 4-hydroxytamoxifen. Succinate accumulation was accompanied with HIF 1-alpha stabilization and SDH inhibition led to lower levels of HIF1-alpha. This indicated that SDH may function in the conversion of fumarate to succinate in LCC9 cells. Our study further investigates the source of fumarate in LCC9 cells. Overall, this study suggests that targeting succinate metabolism may help to restore sensitivity to Fulvestrant and tamoxifen in endocrine therapy resistance in ER+ breast cancer cells.

Citation Format: Anil Yadav, Karla Andrade de Oliveira, Lu Jin, Robert Clarke, Surojeet Sengupta. Impaired Succinate Metabolism Supports Endocrine Therapy Resistance in ER Positive Breast Cancers [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-11-11.

Abstract P3-11-08: Inhibition of Sirtuin 3 Sensitizes Breast Cancer Cells to Fulvestrant

Endocrine therapy can lead to nutrient deprivation by reducing glucose and glutamine uptake and total cellular ATP production. The ability of cells to bypass this metabolic stress is fundamental to how they regulate BC growth and acquire endocrine resistance. Sirtuins (SIRTs) are NAD+-dependent deacylases and regulate a widerange of intracellular processes including metabolism. SIRT3, activated by calorie restriction, modulates mitochondrial adaptation to low energy input. It has a key role in mitochondrial integrity and function, regulating cell survival, death and metabolic pathways, regulating the shift to amino-acid and fatty-acid catabolism. SIRT3 can maintain ROS levels at the appropriate levels for sustaining a proliferative phenotype, preventing apoptosis and promoting carcinogenesis. A role of SIRT3 in epigenetic regulation has also been reported. We used Differential Dependency Network analysis to compare the wiring of the SIRTs and key metabolism-related genes in matched antiestrogen- sensitive vs. resistant breast cancer (BC) cells, which identified several novel signaling hubs including CDKN2A (p16), linking SIRT3 to cell proliferation. The ability of SIRTs to sense and respond to changes in energy, coupled with their deacetylase/deacylase functions, could provide a mechanism for the cell to rewire signaling and maintain a newly acquired drug-resistant phenotype. Using endocrine sensitive (LCC1) and resistant (LCC9) BC cells, we confirmed the higher expression of SIRT3 in LCC9, compared to LCC1 cells. Upregulation of SIRT3 expression within 24 hrs of Fulvestrant (ICI 1 µM) treatment (p=0.0176) in LCC1 was shown, but no effect was observed in LCC9 cells. Conversely, treatment with 17β-estradiol (E2- 10 nM) did not significantly affect SIRT3 expression in either LCC1 or LCC9 cells. Inhibition of SIRT3 acitivity, using the LC0296 inhibitor (15 µM), reduced growth rate in LCC1 and SIRT3-silenced LCC9 cells under treatment with ICI (1 nM and 1 µM, respectively) (p< 0.0001, p< 0.001 respectively). Treatment with SIRTUIN 3 inhibitor and ICI induced apoptosis in LCC1 and SIRT3-silenced LCC9 cells compared to the untreated control and ICI only treated cells (p< 0.001). The combination SIRT3 inhibitor (15 µM) plus ICI (0.5 µM) increased ROS production in LCC9-SIRT3 silenced cells in 24 hours of treatment compared to the untreated control and ICI only treated cells (p< 0.001). SIRT3 inhibitor (15 µM) decreased LCC1 cell spheroid formation (p< 0.05), however it didn’t show additive effect to the effect of ICI (0.5 µM) in the same conditions. The combination of SIRT3 inhibitor (15 µM) and ICI (1 µM) reduced the growth of LCC9 SIRT3-silenced cells in detached condition compared to untreated control and ICI only treated cells (p< 0.001). The results show that SIRT3 may have a role in Fulvestrant response in BC cells; the mechanism is under investigation in our laboratory.

Citation Format: Karla Andrade de Oliveira, Surojeet Sengupta, Lu Jin, Fabia de Oliveira Andrade, Melike Ozgu-Onal, Anil Yadav, Robert Clarke. Inhibition of Sirtuin 3 Sensitizes Breast Cancer Cells to Fulvestrant [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-11-08.

Vitamin D supplementation on prediabetic adults with vitamin D deficiency: a double-blind placebo-controlled randomized clinical trial

Hypovitaminosis D (<20 ng/mL) is thought to increase insulin resistance and meta-inflammation contributing to the pathogenesis of diabetes mellitus (DM). Correcting vitamin D deficiency in people with prediabetes might halt its progression to DM. The aim of this study was to examine the effect of vitamin D supplementation on insulin resistance, glycemic status, and inflammation in prediabetic adults with vitamin D deficiency. This doubleblind randomized placebo-controlled trial was done among 27 newly detected prediabetic adults with hypovitaminosis D randomly assigned to 60,000 IU of vitamin D weekly for eight weeks followed by monthly for the next four months or placebo along with lifestyle modification in both groups [vitamin D (n= 14) vs. Placebo (n=13). They were comparable in terms of sex, age and borlymass index. Glycemic status, fasting plasma glucose (FPG) and Hemoglobin A1C (HbA1C), insulin resistance (homeostasis model assessment of insulin resistance (HOMA-IR) and inflammatory marker high sensitivity C reactive protein (hs-CRP) were measured at baseline and after six months of intervention. Vitamin D levels (ng/mL) increased in both groups from baseline (vitamin D vs. placebo: 12.2±5.9 vs. 3.9±3.5, mean±SD). FPG (mmol/L) significantly decreased in the Vitamin D group (before vs. after: 5.9±0.6 vs. 5.5±0.7, P=0.016, mean±SD), whereas HbA1C (%) and hs- CRP (mg/L) significantly increased in the placebo group (before vs. after- HbA1C: 5.8±0.3 vs. 6.0±0.4, P<0.001; hs-CRP: 5.0±4.4 vs. 5.6±4.9, P=0.039, mean±SD). Percent changes in glycemic status, HOMA-IR, and hs-CRP were statistically similar between the groups. Our study failed to demonstrate the positive effects of vitamin D supplementation on reducing glucose, insulin resistance, or inflammatory marker in prediabetic adult patients with hypovitaminosis D. BSMMU J 2022; 15(3): 167-174

Scheimpflug imaging for evaluation of intraocular lens position in modified flanged scleral fixated intraocular lens

Background

Scleral fixation of intraocular lens (IOLs) is the most preferred technique for the management of aphakia and the techniques have evolved over the years. These methods have their advantages and disadvantages, however, the major concern being the position of the intraocular lens, its stability and complications. The final IOL position is the major determinant of the final visual acuity, and various imaging modalities have been used to quantify the IOL tilt.

Objectives

Use of Scheimpflug imaging to evaluate the IOL tilt in modified flanged scleral-fixated intraocular lens (MFSIOL).

Design

Retrospective chart review of 41 consecutive patients who underwent MFIOL.

Methods

We conducted a retrospective chart review of 41 consecutive patients who underwent MFIOL. The baseline and final best-corrected visual acuity (BCVA), refractive error, and clinical examination findings were recorded. The vertical and horizontal tilts of the IOLs were calculated using the Scheimpflug image. The IOL tilt (in degrees) in the vertical and horizontal axes was the primary outcome and the BCVA, residual refractive error, intraocular pressure, and surgical complications were secondary outcome measures.

Results

The mean baseline BCVA was logMAR 0.49, which improved to logMAR 0.356 (p < .005) after the surgery. The mean IOL tilt in the vertical axis was 3.40° (range of 0.0°-8.5°, interquartile range: 1.21-5.66) and in the horizontal axis was 1.35° (range of 0.60°-4.620°, interquartile range: 0.44-1.86), respectively. There was no correlation between angle of IOL tilt and UCVA (r = 0.089, p = 0.580), BCVA (r = 0.109, p = 0.498), final spherical error (r = 0.081, p = 0.615), cylindrical error (r = 0.207, p = 0.195), axial length (r = 0.105, p = 0.514), and IOL power (r = -0.139, p = 0.388).

Conclusion

Modified flanged IOL (MFIOL) is an alternative technique for intrascleral fixation of IOL resulting in good lens stability. The IOL tilt achieved by this technique is minimal and did not influence the final visual outcome or spectacle correction. Scheimpflug imaging is simple and non-invasive method to measure the IOL tilt.

Plain Language Summary Scheimpflug imaging for modified flanged scleral fixated lens position

This study on 41 eyes was aimed to analyze the lens tilt using Scheimpflug imaging in cases of modified flanged scleral fixation of intraocular lens (MFSFIOL), which is a novel technique to minimize the complications and simplify the procedure. The intraocular lens (IOL) remained stable with an acceptable range of vertical and horizontal tilt. There was no significant effect of IOL tilt on the final best-corrected visual acuity (BCVA) or spectacle correction. Scheimpflug imaging is an accurate and non-invasive technique for assessment of lens position in the patients with intrascleral fixation of IOL.

A Strategic Investigation on Diabetic Nephropathy; Its Conceptual Model and clinical Manifestations: A Review

Diabetes is a major health issue, and its complications can lead to various health problems. Nephropathy has been recognised since the 1930s, when Kimmelstiel and Wilson first reported the characteristic nodular glomerulosclerosis lesions in diabetic kidneys. Diabetic nephropathy (DN), commonly known as diabetic kidney disease, is a condition in which people with diabetes have excessive quantities of urine albumin excretion, diabetic glomerular lesions, and a reduction in their glomerular filtration rate (GFR). Type 1 diabetes (autoimmune -cell destruction and absolute insulin insufficiency), type 2 diabetes (relative insulin deficit and resistance), and others are the three forms of diabetes (e.g., pancreatic disease). Diabetes nephropathy is the leading cause of chronic kidney disease and end-stage renal failure worldwide. Much research has been conducted in both basic science and clinical therapies to enhance the understanding of the mechanism of diabetic nephropathy and expand available therapeutics. Diabetic nephropathy prevention continues to rely on screening for microalbuminuria and treating hyperglycemia. However, several studies suggest that managing diabetic kidney disease is more challenging. Despite comparable hyperglycemic management, some studies suggest that the incidence of renal problems varies by patient. As a result, there has been a great deal of interest in studying the inherent renal protective effects of various antihyperglycemic drugs. This study aims to provide information about the diabetic kidney disease conceptual model, pathogenesis, screening, and diagnosis. It will also address the treatment and prevention of diabetic nephropathy, focusing on comparing the mechanisms, safety profiles, and efficacy of different antihyperglycemic medications.

Optimized Transcriptional Signature for Evaluation of MEK/ERK Pathway Baseline Activity and Long-Term Modulations in Ovarian Cancer

Ovarian cancer is the most aggressive and lethal of all gynecologic malignancies. The high activity of the MEK/ERK signaling pathway is tightly associated with tumor growth, high recurrence rate, and treatment resistance. Several transcriptional signatures were proposed recently for evaluation of MEK/ERK activity in tumor tissue. In the present study, we validated the performance of a robust multi-cancer MPAS 10-gene signature in various experimental models and publicly available sets of ovarian cancer samples. Expression of four MPAS genes (PHLDA1, DUSP4, EPHA2, and SPRY4) displayed reproducible responses to MEK/ERK activity modulations across several experimental models in vitro and in vivo. Levels of PHLDA1, DUSP4, and EPHA2 expression were also significantly associated with baseline levels of MEK/ERK pathway activity in multiple human ovarian cancer cell lines and ovarian cancer patient samples available from the TCGA database. Initial platinum therapy resistance and advanced age at diagnosis were independently associated with poor overall patient survival. Taken together, our results demonstrate that the performance of transcriptional signatures is significantly affected by tissue specificity and aspects of particular experimental models. We therefore propose that gene expression signatures derived from comprehensive multi-cancer studies should be always validated for each cancer type.

Correlates of In-Hospital COVID-19 Deaths: A Competing Risks Survival Time Analysis of Retrospective Mortality Data

INTRODUCTION

Several aspects of the coronavirus disease 2019 (COVID-19) pandemic remain ambiguous, including its transmission, severity, geographic, and racial differences in mortality. These variations merit elaboration of local patterns to inform wider national policies.

METHODS

In a retrospective analysis, data of patients treated at a dedicated COVID hospital with moderate and severe illness during 8 wk of the pandemic were reviewed with attention to mortality in a competing risks framework.

RESULTS

A total of 1147 patients were hospitalized, and 312 (27.2%) died in hospital. Those who died were older (56.5 vs 47.6 y; P < 0.0001). Of these, 885 (77.2%) had tested positive on reverse transcriptase polymerase chain reaction (RT-PCR), with 219 (24.2%) deaths (incidence rate, 1.9 per 100 person-days). Median time from onset of symptoms to death was 11 days. A competing risks analysis for in-hospital death revealed an adjusted cause-specific hazard ratio of 1.4 for each decade increase in age.

CONCLUSIONS

This retrospective analysis provides broad patterns of disease presentation and mortality. Even COVID test-negative patients will receive treatment at dedicated facilities, and 33% presenting cases may die within the first 72 h, most with comorbid illness. This should be considered while planning distribution of services for effective health-care delivery.

Methanol extraction revealed anticancer compounds Quinic Acid, 2(5H)‑Furanone and Phytol in Andrographis paniculata

Andrographis paniculata (Ap) has been a part of traditional medicine for its anti-inflammatory effects, treatment of snake bites and liver abnormalities. Several investigations have revealed its bioactive components to be andrographolides. The methanolic extracts of leaves from Ap were characterized, the non-andrographolides were identified and screened for anti-proliferative activity. The extracts showed significant toxicity against numerous cancer cells including HeLa, MCF7, BT549, 293 and A549 cells. Anti-proliferative activity and effect on cancer cell invasion (metastatic potential) and cell migration were examined. The extracts revealed significant inhibition of the ability of HeLa cells in repairing the gap created by a vertical wound made on a confluent cell monolayer. Similarly, a 40% reduction in cell migration was observed in presence of the extracts. Significant anti-angiogenic activity in terms of reduced blood capillary formation was observed on the Chorioallantoic membranes of embryonated hen eggs co-inoculated with HeLa cells and the extracts. Analysis of HeLa cells treated with the extracts using flow cytometry indicated the arrest of cell cycle progression at the G2/M phase. Variation in the Bax/Bcl-2 ratio and elevated caspase-3 levels by immunoblotting confirmed cell death induction via the apoptotic pathway. Investigation of the extracts by gas chromatography-mass spectrometry displayed the predominant components to be 2(5H)-Furanone (14.73%), Quinic acid (17.32%), and Phytol (11.43%). These components have been previously known to have anticancer activity, while being studied individually in other plants. This is the first study, to the best of our knowledge, on the anti-proliferative and anti-angiogenic activity of the non-andrographolide components from Ap.

A Comprehensive review on Nutritional and Medicinal properties of Pleurotus ostreatus: An Oyster Mushroom

Abstract:

Mushrooms are an important aspect of the human diet, and their popularity has increased over the years. Pleurotus ostreatus (P. ostreatus) are the most commonly consumed mushrooms by the rural dwellers in South Western Nigeria, perhaps, based on their nutritive value and health-enhancing benefits. Pleurotus is a genus of about 40 mushroom species popularly referred to as "oyster mushrooms." P. ostreatus is one of several Pleurotus species that are widely consumed for their flavour, nutritional value, and medicinal properties. Polysaccharides, proteins, peptides, triterpenoids, lectins, lipids, and their derivatives are all found in the P. ostreatus mushroom, in addition to its essential therapeutic components. P. ostreatus commonly consumed as food or as food supplement have been reported in folklore for their antihypertensive property with limited scientific proof. This review emphasizes the excellent nutritional value of P. ostreatus mushrooms.

Extended length of stay and related costs associated with dementia in acute care hospitals in Ireland

OBJECTIVE

To estimate the additional impact of dementia on in-patient length of stay (LOS) and related costs in Irish acute hospitals. Both principal and secondary diagnosis effects are estimated and valued.

METHODS

This is a cross-sectional study based on administrative data collected on all public hospital in-patient discharges in Ireland for people aged 65 years and older in 2019. Coarsened exact matching (CEM) was undertaken to account for observed confounders between dementia and non-dementia groups, while generalised linear modelling (GLM) was used to compare differences in LOS.

RESULTS

Patients with a principal diagnosis of dementia spent on average 17.5 (CI: 15.42, 19.56; p < .01) d longer in hospital than similar patients with no principal diagnosis of dementia. LOS was 6.7 (CI: 6.31, 7.14; p < .01) d longer for patients with a secondary diagnosis of dementia compared to similar patients with no secondary diagnosis of dementia. The additional annual cost of care for patients in hospitals with a secondary (principal) diagnosis of dementia was €62.0 million (€13.2 million).

CONCLUSIONS

This study highlights the economic impact of extended LOS for patients with dementia in Irish acute hospitals. Addressing specific dementia-related needs of people in hospital is likely to optimise resource use and decrease health care costs in acute care settings.

Microsatellite instability in north Indian colorectal cancer patients and its clinicopathological correlation

BACKGROUND

Colorectal cancer (CRC) is the third most deadly and fourth most commonly diagnosed cancer in the world. Microsatellite instability (MSI) has been found associated with CRC, especially in prognostication. The present study has been carried out to find the genetic instability as demonstrated by MSI and its clinicopathological correlation in north Indian patients.

METHODS

This prospective study was carried out on 103 CRC patients admitted for surgery between 2014 and 2018. MSI testing was done using 5-panel markers (BAT25, BAT26, D2S123, D5S346, and D17S250) by standard polymerase chain reaction (PCR) technique. The various clinicopathological factors were analysed to see their association with MSI status and also their effect on survival. Univariate analysis was performed by using the 2-tailed Student's t-test for continuous non-normally distributed variables, and categorical variables were compared using the chi-square test. Multivariate correlation analysis was performed by logistic regression test using SPSS version 16.0 (IBM Corporation, Armonk, NY, USA). Kaplan-Meier analysis was done to detect the patient's survival. A p-value < 0.05 was considered statistically significant.

RESULTS

The frequency of MSI in patient population that we studied was 41.7% (43/103). MSI tumours were significantly associated with family history (OR = 5.63, p = 0.022*, 95% CI = 1.1-28.6) and tumour-infiltrating lymphocytes (TILS) (OR = 2.60, p = 0.023*, 95% CI = 1.1-6.0). The patients surviving longer (< 5 years vs > 5 years) were found significantly associated with MSI-high (MSI-H) (OR = 3.76, p = 0.029*, 95% CI = 1.2-4.5).

CONCLUSION

Family history of cancer and presence of TILS were significantly associated with the presence of MSI-H tumours; also, patients surviving more than 5 years had more MSI-H phenotype.

Vitamin D Status in Prediabetes and its Different Categories

Objectives: Data regarding vitamin D level and status among categories of prediabetes are scarce in the literature. This study is aimed to determine the level and status of vitamin D among adults with prediabetes and its different categories. Materials and methods: This crosssectional study was carried out in 111 newly detected adults with prediabetes according to American Diabetes Association 2018 criteria and 74 matched healthy control (normal glucose tolerance). People with prediabetes were categorized into impaired glucose tolerance, impaired fasting glucose and their combination group. Participants were recruited consecutively from the Department of Endocrinology, BSMMU to measure serum 25 hydroxyvitamin D by high performance liquid chromatography and serum intact parathormone, calcium, albumin and phosphate by chemiluminescent enzyme-labeled immunometric assay. Results: Vitamin D level and status were not significantly different between people with prediabetes & control and also in different categories of prediabetes. Severe vitamin D deficiency was significantly higher in people with prediabetes (27.5% vs 10%, p= 0.05). There were no associations between different blood glucose levels with vitamin D among adults with prediabetes. Conclusions:Vitamin D was not associated with prediabetes or its categories. Bangladesh Journal of Medical Science Vol. 21(1) 2022 Page : 120-128

Diagnosis of osteoarticular tuberculosis by immuno-PCR assay based on mycobacterial antigen 85 complex detection

Diagnosis of osteoarticular tuberculosis (OATB) exhibits serious challenges owing to paucibacillary nature of specimens and localization of disease at sites that are difficult to access. We recently developed indirect immuno-PCR (I-PCR) and real-time I-PCR (RT-I-PCR) assays for the detection of mycobacterial antigen 85 complex (Ag85) in OATB patients. Detection limits for the purified Ag85 protein were found to be 1 and 41 fg ml^-1 by I-PCR and RT-I-PCR, respectively, which were at least 10⁵ -fold lower than respective ELISA. While spiking synovial fluids of non-TB control subjects with the purified Ag85 protein, LODs of 100 and 120 fg ml^-1 were obtained by I-PCR and RT-I-PCR, respectively, thus demonstrating the sample matrix effect. Sensitivities of 87·5 and 70·5% were observed in bodily fluids of confirmed (n = 8) and clinically suspected (n = 51) OATB cases, respectively, by I-PCR, with a specificity of 93·9% (n = 33). Markedly, the sensitivities obtained by I-PCR/RT-I-PCR were significantly higher (P < 0·05-0·01) than ELISA and GeneXpert assay (n = 30). However, no substantial difference in sensitivity was observed between the I-PCR and RT-I-PCR assays. After further improving the accuracy of I-PCR, this test may lead to development of an attractive diagnostic kit.

Genome-wide analysis in 756,646 individuals provides first genetic evidence that ACE2 expression influences COVID-19 risk and yields genetic risk scores predictive of severe disease

SARS-CoV-2 enters host cells by binding angiotensin-converting enzyme 2 (ACE2). Through a genome-wide association study, we show that a rare variant (MAF = 0.3%, odds ratio 0.60, P=4.5×10^-13) that down-regulates ACE2 expression reduces risk of COVID-19 disease, providing human genetics support for the hypothesis that ACE2 levels influence COVID-19 risk. Further, we show that common genetic variants define a risk score that predicts severe disease among COVID-19 cases.