Publications by authors named "Md Mahbubur Rahman"

93 Publications

Evaluation of Cyclic Amides as Activating Groups in N-C Bond Cross-Coupling: Discovery of -Acyl-δ-valerolactams as Effective Twisted Amide Precursors for Cross-Coupling Reactions.

J Org Chem 2021 Jul 17. Epub 2021 Jul 17.

Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States.

The development of efficient methods for facilitating N-C(O) bond activation in amides is an important objective in organic synthesis that permits the manipulation of the traditionally unreactive amide bonds. Herein, we report a comparative evaluation of a series of cyclic amides as activating groups in amide N-C(O) bond cross-coupling. Evaluation of -acyl-imides, -acyl-lactams, and -acyl-oxazolidinones bearing five- and six-membered rings using Pd(II)-NHC and Pd-phosphine systems reveals the relative reactivity order of N-activating groups in Suzuki-Miyaura cross-coupling. The reactivity of activated phenolic esters and thioesters is evaluated for comparison in O-C(O) and S-C(O) cross-coupling under the same reaction conditions. Most notably, the study reveals -acyl-δ-valerolactams as a highly effective class of mono--acyl-activated amide precursors in cross-coupling. The X-ray structure of the model -acyl-δ-valerolactam is characterized by an additive Winkler-Dunitz distortion parameter Σ(τ+χ) of 54.0°, placing this amide in a medium distortion range of twisted amides. Computational studies provide insight into the structural and energetic parameters of the amide bond, including amidic resonance, N/O-protonation aptitude, and the rotational barrier around the N-C(O) axis. This class of -acyl-lactams will be a valuable addition to the growing portfolio of amide electrophiles for cross-coupling reactions by acyl-metal intermediates.
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http://dx.doi.org/10.1021/acs.joc.1c01110DOI Listing
July 2021

Antiproliferative and antioxidant potentials of bioactive edible vegetable fraction of Roxb. in cancer cell line.

Food Sci Nutr 2021 Jul 1;9(7):3777-3805. Epub 2021 Jun 1.

Department of Pharmacy University of Rajshahi Rajshahi Bangladesh.

In the present study, the aerial parts of underwent investigation of their in vitro antioxidant and free radical-scavenging activities in cell-free conditions, their phytoconstituents using gas chromatography-mass spectrometry (GC-MS), and their cytotoxic activity in HeLa cells. was extracted with 80% methanol and successively fractionated with solvents to yield petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF), and aqueous (AQF) fractions. GC-MS analysis revealed that CHF contained ten phytoconstituents, including different forms of octadecanoic acid methyl esters. The total antioxidant and ferric-reducing antioxidant capacities of the extracts and the standard catechin (CA) were as follows: CA >CHF >PEF >CME (crude methanolic extract) >EAF >AQF, and CA >CHF >EAF >PEF >AQF >CME, respectively. CHF showed the highest DPPH-free radical-scavenging activity, with a median inhibitory concentration of 10.5 ± 0.28 µg/ml, which was slightly higher than that of the standard butylated hydroxytoluene (12.0 ± 0.09 µg/ml). In the hydroxyl radical-scavenging assay, CHF showed identical scavenging activity (9.25 ± 0.73 µg/ml) when compared to CA (10.50 ± 1.06 µg/ml). Moreover, CHF showed strong cytotoxic activity (19.95 ± 1.18 µg/ml) in HeLa cells, which was alike to that of the standards vincristine sulfate and 5-fluorouracil (15.84 ± 1.64 µg/ml and 12.59 ± 1.75 µg/ml, respectively). The in silico study revealed that identified compounds were significantly linked to the targets of various cancer cells and oxidative enzymes. However, online prediction by SwissADME, admetSAR, and PASS showed that it has drug-like, nontoxic, and potential pharmacological actions.
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http://dx.doi.org/10.1002/fsn3.2343DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8269638PMC
July 2021

Anticholinesterase Activity of Eight Medicinal Plant Species: and Studies in the Search for Therapeutic Agents against Alzheimer's Disease.

Evid Based Complement Alternat Med 2021 25;2021:9995614. Epub 2021 Jun 25.

Department of Science, University of Basilicata, Viale Dell'Ateneo Lucano 10, Potenza 85100, Italy.

Many Bangladeshi medicinal plants have been used to treat Alzheimer's disease and other neurodegenerative diseases. In the present study, the anticholinesterase effects of eight selected Bangladeshi medicinal plant species were investigated. Species were selected based on the traditional uses against CNS-related diseases. Extracts were prepared using a gentle cold extraction method. cholinesterase inhibitory effects were measured by Ellman's method in 96-well microplates. (Compositae) and (Menispermaceae) were found to have the highest acetylcholinesterase inhibitory (IC 150 ± 11 and 176 ± 14 g/mL, respectively) and butyrylcholinesterase inhibitory effect (IC, 297 ± 13 and 124 ± 2 g/mL, respectively). demonstrated competitive inhibition, where showed an uncompetitive inhibition mode for acetylcholinesterase. (Smilacaceae) and (Malvaceae) were also found to show moderate AChE inhibition (IC 205 ± 31 and 221 ± 2 g/mL, respectively), although no significant BChE inhibitory effect was observed for extracts from these plant species. Among others, grandiflora (Acanthaceae) and (Compositae) were found to display noticeable AChE (IC, 252 ± 22 g/mL) and BChE (IC, 314 ± 15 g/mL) inhibitory effects, respectively. Molecular docking experiment suggested that compounds 5-hydroxy-3,6,7,3',4'-pentamethoxyflavone (BL4) and kaempferol-3---L-rhamnopyranosyl-(1⟶6)--D-glucopyranoside (BL5) from bound stably to the binding groove of the AChE and BChE by hydrogen-bond interactions, respectively. Therefore, these compounds could be candidates for cholinesterase inhibitors. The present findings demonstrated that and are interesting objects for further studies aiming at future therapeutics for Alzheimer's disease.
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http://dx.doi.org/10.1155/2021/9995614DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8260289PMC
June 2021

Functional and Predictive Structural Characterization of WRINKLED2, A Unique Oil Biosynthesis Regulator in Avocado.

Front Plant Sci 2021 8;12:648494. Epub 2021 Jun 8.

Department of Biological Sciences, East Tennessee State University, Johnson City, TN, United States.

WRINKLED1 (WRI1), a member of the APETALA2 (AP2) class of transcription factors regulates fatty acid biosynthesis and triacylglycerol (TAG) accumulation in plants. Among the four known paralogs, only was unable to complement and restore fatty acid content in mutant seeds. Avocado () mesocarp, which accumulates 60-70% dry weight oil content, showed high expression levels for orthologs of , along with and , during fruit development. While the role of WRI1 as a master regulator of oil biosynthesis is well-established, the function of WRI1 paralogs is poorly understood. Comprehensive and comparative analyses of WRI1 paralogs from avocado (a basal angiosperm) with higher angiosperms (dicot), maize (monocot) revealed distinct features. Predictive structural analyses of the WRI orthologs from these three species revealed the presence of AP2 domains and other highly conserved features, such as intrinsically disordered regions associated with predicted PEST motifs and phosphorylation sites. Additionally, avocado WRI proteins also contained distinct features that were absent in the nonfunctional ortholog WRI2. Through transient expression assays, we demonstrated that both avocado WRI1 and WRI2 are functional and drive TAG accumulation in leaves. We predict that the unique features and activities of ancestral were likely lost in orthologous genes such as during evolution and speciation, leading to at least partial loss of function in some higher eudicots. This study provides us with new targets to enhance oil biosynthesis in plants.
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http://dx.doi.org/10.3389/fpls.2021.648494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8218904PMC
June 2021

Unfolding the apoptotic mechanism of antioxidant enriched-leaves of Tabebuia pallida (lindl.) miers in EAC cells and mouse model.

J Ethnopharmacol 2021 Oct 10;278:114297. Epub 2021 Jun 10.

Department of Pharmacy, University of Rajshahi, Rajshahi, 6205, Bangladesh. Electronic address:

Ethnopharmacological Relevance: Tabebuia pallida (Lindl.) Miers (T. pallida) is a well-known native Caribbean medicinal plant. The leaves and barks of T. pallida are used as traditional medicine in the form of herbal or medicinal tea to manage cancer, fever, and pain. Moreover, extracts from the leaves of T. pallida showed anticancer activity. However, the chemical profile and mechanism of anticancer activity of T. pallida leaves (TPL), stem bark (TPSB), root bark (TPRB) and flowers (TPF) remain unexplored.

Aim Of The Study: The present study was designed to explore the regulation of apoptosis by T. pallida using Ehrlich Ascites Carcinoma (EAC) cultured cells and an EAC mouse model. LC-ESI-MS/MS was used for compositional analysis of T. pallida extracts.

Materials And Methods: Dried and powdered TPL, TPSB, TPRB and TPF were extracted with 80% methanol. Using cultured EAC cells and EAC-bearing mice with and without these extracts, anticancer activities were studied by assessing cytotoxicity and tumor cell growth inhibition, changes in life span of mice, and hematological and biochemical parameters. Apoptosis was analyzed by microscopy and expression of selected apoptosis-related genes (Bcl-2, Bcl-xL, NFκ-B, PARP-1, p53, Bax, caspase-3 and -8) using RT-PCR. LC-ESI-MS analysis was performed to identify the major compounds from active extracts. Computer aided analyses was undertaken to sort out the best-fit phytoconstituent of total ten isolated compounds of this plant for antioxidant and anticancer activity.

Results: In EAC mice compared with untreated controls, the TPL extract exhibited the highest cancer cell toxicity with significant tumor cell growth inhibition (p < 0.001), reduced ascites by body weight (p < 0.01), increased the life span (p < 0.001), normalized blood parameters (RBC/WBC counts), and increased the levels of superoxide dismutase and catalase. TPL-treated EAC cells showed increased apoptotic characteristics of membrane blebbing, chromatin condensation and nuclear fragmentation, and caspase-3 activation, compared with untreated EAC cells. Moreover, annexin V-FITC and propidium iodide signals were greatly enhanced in response to TPL treatment, indicating apoptosis induction. Pro- and anti-apoptotic signaling after TPL treatment demonstrated up-regulated p53, Bax and PARP-1, and down-regulated NFκ-B, Bcl-2 and Bcl-xL expression, suggesting that TPL shifts the balance of pro- and anti-apoptotic genes towards cell death. LC-ESI-MS data of TPL showed a mixture of glycosides, lapachol, and quercetin antioxidant and its derivatives that were significantly linked to cancer cell targets. The compound, pelargonidin-3-O-glucoside was found to be most effective in computer aided models.

Conclusions: In conclusion, the TPL extract of T. pallida possesses significant anticancer activity. The tumor suppressive mechanism is due to apoptosis induced by activation of antioxidant enzymes and caspases and mediated by a change in the balance of pro- and anti-apoptotic genes that promotes cell death.
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http://dx.doi.org/10.1016/j.jep.2021.114297DOI Listing
October 2021

Automated Detection of Stressful Conversations Using Wearable Physiological and Inertial Sensors.

Proc ACM Interact Mob Wearable Ubiquitous Technol 2020 Dec;4(4)

University of Memphis, Computer Science, Memphis, TN, USA.

Stressful conversation is a frequently occurring stressor in our daily life. Stressors not only adversely affect our physical and mental health but also our relationships with family, friends, and coworkers. In this paper, we present a model to automatically detect stressful conversations using wearable physiological and inertial sensors. We conducted a lab and a field study with cohabiting couples to collect ecologically valid sensor data with temporally-precise labels of stressors. We introduce the concept of stress cycles, i.e., the physiological arousal and recovery, within a stress event. We identify several novel features from stress cycles and show that they exhibit distinguishing patterns during stressful conversations when compared to physiological response due to other stressors. We observe that hand gestures also show a distinct pattern when stress occurs due to stressful conversations. We train and test our model using field data collected from 38 participants. Our model can determine whether a detected stress event is due to a stressful conversation with an F1-score of 0.83, using features obtained from only one stress cycle, facilitating intervention delivery within 3.9 minutes since the start of a stressful conversation.
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http://dx.doi.org/10.1145/3432210DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8180313PMC
December 2020

Myocardial tuberculosis and beyond: A rare form of extra pulmonary TB in a young boy.

Indian J Tuberc 2021 Jul 4;68(3):416-419. Epub 2020 Nov 4.

Pulmonology, National Institute of Diseases of Chest and Hospital (NIDCH), Dhaka, Bangladesh.

Myocardial tuberculosis is an exceptionally rare form of extra-pulmonary TB. Few cases were reported world-wide. Here a young snake charmer who had skin tuberculosis 5 yrs back admitted into National institute of diseases of Chest and hospital (NIDCH), Dhaka with the complaints of cough, palpitation and breathlessness for 2 months. He had right axillary firm matted lymphadenopathy, left sided large pleural effusion, left ventricular and septal hypertrophy with band and mass inside the ventricle (evident on CT scan of heart and echocardiography). His ESR was 95 mm in1st hr, Mantaux test was 15mm, Pleural fluid was exudative lymphocyte predominant with adenosin deaminase (ADA) 68.6 U/L. Fine needle aspirates from right axillary LNs showed Mycobacterium tuberculosis on GeneXpert for MTB/RIF testing and caseous granuloma on cytopathological study. Whole Body F18 FDG PET-CT revealed numerous low FDG avid size significant lymph nodes in right side of neck, mediastinum and right axilla with cardiomegaly with focal FDG avid within the left ventricular cavity likely to be prominent papillary muscle. MRI of heart or Myocardial biopsy for histology was not done due to their cost and invasiveness and also for that there was sufficient evidence of having tuberculosis in lymph node, pleura nas myocardium. This patient was treated with anti tubercular medications (3HRZE2S/5HRE) with prednisolone for six months. After treatment, myocardial lesions, pleural effusion and lymphadenopathy were found resolved. Thus a case of fatal and serious tuberculosis was explored and managed successfully.
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http://dx.doi.org/10.1016/j.ijtb.2019.12.003DOI Listing
July 2021

Synthesis of Sulfoxonium Ylides from Amides by Selective N-C(O) Activation.

Org Lett 2021 Jun 7;23(12):4818-4822. Epub 2021 Jun 7.

Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States.

The direct synthesis of sulfoxonium ylides from amides by selective N-C(O) cleavage is presented. The reaction proceeds through the nucleophilic addition of dimethylsulfoxonium methylide to the amide bond in acyclic twisted amides under exceedingly mild room temperature conditions. A variety of amides can be employed, and the protocol can be applied to the late-stage derivatization of pharmaceuticals. Mechanistic studies outline the relative order of reactivity of amides.
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http://dx.doi.org/10.1021/acs.orglett.1c01535DOI Listing
June 2021

Black Cumin ( L.): A Comprehensive Review on Phytochemistry, Health Benefits, Molecular Pharmacology, and Safety.

Nutrients 2021 May 24;13(6). Epub 2021 May 24.

Department of Pathology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea.

Mounting evidence support the potential benefits of functional foods or nutraceuticals for human health and diseases. Black cumin ( L.), a highly valued nutraceutical herb with a wide array of health benefits, has attracted growing interest from health-conscious individuals, the scientific community, and pharmaceutical industries. The pleiotropic pharmacological effects of black cumin, and its main bioactive component thymoquinone (TQ), have been manifested by their ability to attenuate oxidative stress and inflammation, and to promote immunity, cell survival, and energy metabolism, which underlie diverse health benefits, including protection against metabolic, cardiovascular, digestive, hepatic, renal, respiratory, reproductive, and neurological disorders, cancer, and so on. Furthermore, black cumin acts as an antidote, mitigating various toxicities and drug-induced side effects. Despite significant advances in pharmacological benefits, this miracle herb and its active components are still far from their clinical application. This review begins with highlighting the research trends in black cumin and revisiting phytochemical profiles. Subsequently, pharmacological attributes and health benefits of black cumin and TQ are critically reviewed. We overview molecular pharmacology to gain insight into the underlying mechanism of health benefits. Issues related to pharmacokinetic herb-drug interactions, drug delivery, and safety are also addressed. Identifying knowledge gaps, our current effort will direct future research to advance potential applications of black cumin and TQ in health and diseases.
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http://dx.doi.org/10.3390/nu13061784DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8225153PMC
May 2021

Antiviral phytochemicals as potent inhibitors against NS3 protease of dengue virus.

Comput Biol Med 2021 07 14;134:104492. Epub 2021 May 14.

Department of Physical Sciences, University of Arkansas-Fort Smith, Fort Smith, AR, USA. Electronic address:

Dengue, a mosquito-borne disease, has appeared as a major infectious disease globally. The virus requires its proteins to replicate and reproduce in the host cell. The NS3 protease converts the polyprotein to functional proteins with the help of the NS2B cofactor. Thus, NS3 protease is a promising target to develop antiviral inhibitors against the dengue virus. A systematic screening including ADMET properties, molecular docking, molecular dynamics (MD) simulation, binding free energy calculation, and QSAR studies is carried out to predict potent inhibitors against the NS3 protease. From the screening of 40 antiviral phytochemicals, ADMET properties analysis was used to screen out ligands that violate ADME rules and have probable toxicity. Cyanidin 3-Glucoside, Dithymoquinone, and Glabridin were predicted to be potent inhibitors against the NS3 protease according to their binding affinity. These ligands showed several noncovalent interactions, including hydrogen bond, hydrophobic interaction, electrostatic interaction, pi-sulfur interactions. The ligand-protein complexes were further scrutinized using 250 ns molecular dynamics simulation. The MM-PBSA binding free energy calculation was conducted to investigate their binding stability in dynamic conditions. The calculated pIC50(mM) value was predicted using the QSAR model with 89.91% goodness of fit. The predicted biologocal activity value for the ligands indicates they might have good potency.
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http://dx.doi.org/10.1016/j.compbiomed.2021.104492DOI Listing
July 2021

Gut probiotic bacteria of Barbonymus gonionotus improve growth, hematological parameters and reproductive performances of the host.

Sci Rep 2021 May 21;11(1):10692. Epub 2021 May 21.

Institute of Biotechnology and Genetic Engineering, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, 1706, Bangladesh.

This study aimed to isolate and identify probiotic bacteria from the gut of Barbonymus gonionotus and evaluate their effects on growth, hematological parameters, and breeding performances of the host. Five probiotic bacteria viz. Enterococcus xiangfangensis (GFB-1), Pseudomonas stutzeri (GFB-2), Bacillus subtilis (GFB-3), Citrobacter freundii (GFB-4), and P. aeruginosa (GFB-5) were isolated and identified using 16S rRNA gene sequencing. Application of a consortium of probiotic strains (1-3 × 1.35 × 10 CFU kg) or individual strain such as GFB-1 (1.62 × 10 CFU kg), GFB-2 (1.43 × 10 CFU kg), GFB-3 (1.06 × 10 CFU kg), GFB-4 (1.5 × 10 CFU kg) or GFB-5 (1.43 × 10 CFU kgfeed) through feed significantly improved growth, histological and hematological parameters and reproductive performances of B. gonionotus compared to untreated control. Moreover, the application of these probiotics significantly increased gut lactic acid bacteria and activities of digestive enzymes but did not show any antibiotic resistance nor any cytotoxicity in vitro. The highest beneficial effects on treated fishes were recorded by the application of GFB-1, GFB-2, GFB-3, and a consortium of these bacteria (T2). This is the first report of the improvement of growth and health of B. gonionotus fishes by its gut bacteria.
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http://dx.doi.org/10.1038/s41598-021-90158-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8140159PMC
May 2021

Entelon (vitis vinifera seed extract) reduces degenerative changes in bovine pericardium valve leaflet in a dog intravascular implant model.

PLoS One 2021 4;16(3):e0235454. Epub 2021 Mar 4.

Department of Thoracic and Cardiovascular Surgery, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea.

Background And Aims: Inflammation and calcification are major factors responsible for degeneration of bioprosthetic valve and other substitute heart valve implantations. The objective of this study was to evaluate the anti-inflammatory and anti-calcification effects of Entelon150® (consisting of grape-seed extract) in a beagle dog model of intravascular bovine pericardium implantation.

Methods: In total, 8 healthy male beagle dogs were implanted with a bovine pericardium bilaterally in the external jugular veins and divided into two groups. Animals in the Entelon150® group (n = 4) were treated with 150 mg of Entelon150® twice daily for six weeks after surgery. The negative control (NC) group (n = 4) was treated with 5 ml of saline using the same method. After six weeks, we measured the calcium content, performed histological examination, and performed molecular analysis.

Results: The calcium content of implanted tissue in the Entelon150® group (0.56±0.14 mg/g) was significantly lower than that in the NC group (1.48±0.57 mg/g) (p < 0.05). Histopathological examination showed that infiltration of chronic inflammatory cells, such as fibroblasts and macrophages, occurred around the graft in all groups; however, the inflammation level of the implanted tissue in the Entelon150® group was s lower than that in the NC group. Both immunohistochemical and western blot analyses revealed that bone morphogenetic protein 2 expression was significantly attenuated in the Entelon150® group.

Conclusions: Our results indicate that Entelon150® significantly attenuates post-implantation inflammation and degenerative calcification of the bovine pericardium in dogs. Therefore, Entelon150® may increase the longevity of the bovine pericardium after intravascular implantation.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0235454PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7932063PMC
March 2021

2D metal azolate framework as nanozyme for amperometric detection of glucose at physiological pH and alkaline medium.

Mikrochim Acta 2021 Feb 10;188(3):77. Epub 2021 Feb 10.

Department of Energy and Materials, Konkuk University, Chungju, 27478, Republic of Korea.

The synthesis of Co-based two-dimensional (2D) metal azolate framework nanosheets (MAF-5-Co NS) is described using a simple hydrothermal method. The product was isostructural to MAF-5 (Zn). The as-prepared MAF-5-Co NS exhibited high surface area (1155 m/g), purity, and crystallinity. The MAF-5-Co NS-modified screen-printed electrode (MAF-5-Co NS/SPE) was used for nonenzymatic detection of glucose in diluted human blood plasma (BP) samples with phosphate buffer saline (PBS, pH 7.4) and NaOH (0.1 M, pH 13.0) solutions. The MAF-5-Co NS nanozyme displayed good redox activity in both neutral and alkaline media with the formation of Co/Co redox pair, which induced the catalytic oxidation of glucose. Under the optimized detection potential, the sensor presented a chronoamperometric current response for the oxidation of glucose with two wide concentration ranges in PBS-diluted (62.80 to 180 μM and 305 to 8055 μM) and NaOH-diluted (58.90 to 117.6 μM and 180 to 10,055 μM) BP samples, which were within the limit of blood glucose levels of diabetic patients before (4.4-7.2 mM) and after (10 mM) meals (recommended by the American Diabetes Association). The sensor has a limit of detection of ca. 0.25 and 0.05 μM, respectively, and maximum sensitivity of ca. 36.55 and 1361.65 mA/cm/mM, respectively, in PBS- and NaOH-diluted BP samples. The sensor also displayed excellent stability in the neutral and alkaline media due to the existence of hydrophobic linkers (2-ethyl imidazole) in the MAF-5-Co NS, good repeatability and reproducibility, and interference-free signals. Thus, MAF-5-Co NS is a promising nanozyme for the development of the disposable type of sensor for glucose detection in human body fluids. Graphical abstract.
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http://dx.doi.org/10.1007/s00604-021-04737-wDOI Listing
February 2021

Traditional foods with their constituent's antiviral and immune system modulating properties.

Heliyon 2021 Jan 14;7(1):e05957. Epub 2021 Jan 14.

Department of Pharmacy, University of Rajshahi, Rajshahi, 6205, Bangladesh.

Background: Viruses are responsible for several diseases, including severe acute respiratory syndrome, a condition caused by today's pandemic coronavirus disease (COVID-19). A negotiated immune system is a common risk factor for all viral infections, including COVID-19. To date, no specific therapies or vaccines have been approved for coronavirus. In these circumstances, antiviral and immune boosting foods may ensure protection against viral infections, especially SARS-CoV-2 by reducing risk and ensuring fast healing of SARS-CoV-2 illness.

Scope And Approach: In this review, we have conducted an online search using several search engines (Google Scholar, PubMed, Web of Science and Science Direct) to find out some traditional foods (plant, animal and fungi species), which have antiviral and immune-boosting properties against numerous viral infections, particularly coronaviruses (CoVs) and others RNA-virus infections. Our review indicated some foods to be considered as potential immune enhancers, which may help individuals to overcome viral infections like COVID-19 by modulating immune systems and reducing respiratory problems. Furthermore, this review will provide information regarding biological properties of conventional foods and their ingredients to uphold general health.

Key Findings And Conclusions: We observed some foods with antiviral and immune-boosting properties, which possess bioactive compounds that showed significant antiviral properties against different viruses, particularly RNA viruses such as CoVs. Interestingly, some antiviral and immune-boosting mechanisms were very much similar to the antiviral drug of COVID-19 homologous SARS (Severe Acute Respiratory Syndrome Coronavirus) and MERS (Middle East Respiratory Syndrome Coronavirus). The transient nature and the devastating spreading capability of COVID-19 lead to ineffectiveness of many curative therapies. Therefore, body shielding and immune-modulating foods, which have previous scientific recognition, have been discussed in this review to discern the efficacy of these foods against viral infections, especially SARS-CoV-2.
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http://dx.doi.org/10.1016/j.heliyon.2021.e05957DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7806454PMC
January 2021

Transamidation of Amides and Amidation of Esters by Selective N-C(O)/O-C(O) Cleavage Mediated by Air- and Moisture-Stable Half-Sandwich Nickel(II)-NHC Complexes.

Molecules 2021 Jan 2;26(1). Epub 2021 Jan 2.

Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.

The formation of amide bonds represents one of the most fundamental processes in organic synthesis. Transition-metal-catalyzed activation of acyclic twisted amides has emerged as an increasingly powerful platform in synthesis. Herein, we report the transamidation of -activated twisted amides by selective N-C(O) cleavage mediated by air- and moisture-stable half-sandwich Ni(II)-NHC (NHC = N-heterocyclic carbenes) complexes. We demonstrate that the readily available cyclopentadienyl complex, [CpNi(IPr)Cl] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene), promotes highly selective transamidation of the N-C(O) bond in twisted N-Boc amides with non-nucleophilic anilines. The reaction provides access to secondary anilides via the non-conventional amide bond-forming pathway. Furthermore, the amidation of activated phenolic and unactivated methyl esters mediated by [CpNi(IPr)Cl] is reported. This study sets the stage for the broad utilization of well-defined, air- and moisture-stable Ni(II)-NHC complexes in catalytic amide bond-forming protocols by unconventional C(acyl)-N and C(acyl)-O bond cleavage reactions.
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http://dx.doi.org/10.3390/molecules26010188DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7795584PMC
January 2021

Fabrication of highly and poorly oxidized silver oxide/silver/tin(IV) oxide nanocomposites and their comparative anti-pathogenic properties towards hazardous food pathogens.

J Hazard Mater 2021 04 30;408:124896. Epub 2020 Dec 30.

International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. Electronic address:

Herein, we report the fabrication of highly oxidized silver oxide/silver/tin(IV) oxide (HOSBTO or Ag-enriched AgO/Ag/SnO) nanocomposite under a robust oxidative environment created with the use of concentrated nitric acid. Tin(IV) hydroxide nanofluid is added to the reaction mixture as a stabilizer for the Ag-enriched silver oxide in the nanocomposite. The formation of Ag nanoparticles in this nanocomposite originates from the decomposition of silver oxides during calcination at 600 °C. For comparison, poorly oxidized silver oxide/silver/tin(IV) oxide (POSBTO with formula AgO/Ag/SnO) nanocomposite has also been prepared by following the same synthetic procedures, except for the use of concentrated nitric acid. Finally, we studied in detail the anti-pathogenic capabilities of both nanocomposites against four hazardous pathogens, including pathogenic fish bacterium (Stenotrophomonas maltophilia stain EP10), oomycete (Phytophthora cactorum strain P-25), and two different strains of pathogenic strawberry fungus, BRSP08 and BRSP09 (Collectotrichum siamense). The bioassays reveal that the as-prepared HOSBTO and POSBTO nanocomposites exhibit significant inhibitory activities against the tested pathogenic bacterium, oomycete, and fungus in a dose-dependent manner. However, the degree of dose-dependent effectiveness of the two nanocomposites against each pathogen largely varies.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124896DOI Listing
April 2021

Prospects of honey in fighting against COVID-19: pharmacological insights and therapeutic promises.

Heliyon 2020 Dec 21;6(12):e05798. Epub 2020 Dec 21.

ABEx Bio-Research Center, East Azampur, Dhaka 1230, Bangladesh.

Honey and its compounds are drawing attention as an effective natural therapy because of its ability to attenuate acute inflammation through enhancing immune response. Several studies have proved its potential healing capability against numerous chronic diseases/conditions, including pulmonary disorders, cardiac disorders, diabetes, hypertension, autophagy dysfunction, bacterial, and fungal infections. More importantly, honey has proved its virucidal effect on several enveloped viruses such as HIV, influenza virus, herpes simplex, and varicella-zoster virus. Honey may be beneficial for patients with COVID-19 which is caused by an enveloped virus SARS-CoV-2 by boosting the host immune system, improving comorbid conditions, and antiviral activities. Moreover, a clinical trial of honey on COVID-19 patients is currently undergoing. In this review, we have tried to summarize the potential benefits of honey and its ingredients in the context of antimicrobial activities, some chronic diseases, and the host immune system. Thus, we have attempted to establish a relationship with honey for the treatment of COVID-19. This review will be helpful to reconsider the insights into the possible potential therapeutic effects of honey in the context of the COVID-19 pandemic. However, the effects of honey on SARS-CoV-2 replication and/or host immune system need to be further investigated by and studies.
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http://dx.doi.org/10.1016/j.heliyon.2020.e05798DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7750705PMC
December 2020

A highly sensitive poly(chrysoidine G)-gold nanoparticle composite based nitrite sensor for food safety applications.

Anal Methods 2020 12 23;12(46):5562-5571. Epub 2020 Nov 23.

Department of Physics, College of Science, King Faisal University, P.O. Box 400, Hofuf, Al-Ahsa 31982, Saudi Arabia.

This work demonstrated the development of conducting poly(chrysoidine G) (PCG)-gold nanoparticle (AuNP)-modified fluorine-doped tin oxide (F : SnO, FTO) film-coated glass electrodes for the sensitive electrochemical detection of nitrite (NO). The homogeneously distributed PCG nanoparticle layer was deposited onto the FTO electrode by cyclic voltammetry sweeping. AuNPs were then anchored onto the PCG/FTO electrode by the chemical reduction of pre-adsorbed Au ions. The as-prepared AuNP/PCG/FTO electrode exhibited excellent electrocatalytic activity for the oxidation of NO with high sensitivity (approximately 0.63 μA cmμM) and a low limit of detection (0.095 μM), which is relevant within the normal concentration range of NO in human bodily fluids. The AuNP/PCG/FTO sensor showed sufficient reproducibility, repeatability, low interference, and strong recovery for NO detection in food samples. These results indicate that the AuNP/PCG nanocomposites have immense potential for the electrochemical detection of other biologically important compounds.
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http://dx.doi.org/10.1039/d0ay01761bDOI Listing
December 2020

Amplicon sequencing reveals significantly increased Vibrio abundance and associated gene functions in vibriosis-infected black tiger shrimp (Penaeus monodon).

J Fish Dis 2021 May 18;44(5):591-599. Epub 2020 Nov 18.

Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia.

Vibriosis caused by luminous Vibrio species is one of the biggest challenges to shrimp industry in Bangladesh. This study aimed to characterize whole microbial communities from Vibrio-infected black tiger shrimp (Penaeus monodon) using 16S rRNA-based amplicon sequencing. A total of 36 disease-free and infected shrimp were collected from six different hatcheries in Bagerhat, Bangladesh. A final pool of 12 samples (n = 6) was created by homogenization of the hepatopancreas samples from three shrimps collected from each hatchery for the same group. The amplicon sequencing data revealed significant (p < .05) decrease of alpha diversity measurements and subsequent effects (p < .05) on the hepatopancreas microbiota in the infected group, compared to control shrimp. Proteobateria and Aeromonas were the most dominant bacteria at phylum and genus level in both groups and identified as core microbiota in the community. Two bacterial groups at phyla level and eight at genus level were found associated with the alteration of hepatopancreas microbial communities and associated gene functions in vibriosis-infected shrimp, revealed by differential abundance and KEGG pathway analysis. The overwhelming abundance of Citroibacter, Shewanella and Candidatus lineages in vibriosis-infected shrimp needs further investigations.
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http://dx.doi.org/10.1111/jfd.13304DOI Listing
May 2021

Adapting to Noise in Speech Obfuscation by Audio Profiling Using Generative Models for Passive Health Monitoring.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:5700-5704

Passive health monitoring has been introduced as a solution for continuous diagnosis and tracking of subjects' condition with minimal effort. This is partially achieved by the technology of passive audio recording although it poses major audio privacy issues for subjects. Existing methods are limited to controlled recording environments and their prediction is significantly influenced by background noises. Meanwhile, they are too compute-intensive to be continuously running on smart phones. In this paper, we implement an efficient and robust audio privacy preserving method that profiles the background audio to focus only on audio activities detected during recording for performance improvement, and to adapt to the noise for more accurate speech segmentation. We analyze the performance of our method using audio data collected by a smart watch in lab noisy settings. Our obfuscation results show a low false positive rate of 20% with a 92% true positive rate by adapting to the recording noise level. We also reduced model memory footprint and execution time of the method on a smart phone by 75% and 62% to enable continuous speech obfuscation.
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http://dx.doi.org/10.1109/EMBC44109.2020.9176156DOI Listing
July 2020

CoughMatch - Subject Verification Using Cough for Personal Passive Health Monitoring.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:5689-5695

Automatic cough detection using audio has advanced passive health monitoring on devices such as smart phones and wearables; it enables capturing longitudinal health data by eliminating user interaction and effort. One major issue arises when coughs from surrounding people are also detected; capturing false coughs leads to significant false alarms, excessive cough frequency, and thereby misdiagnosis of user condition. To address this limitation, in this paper, a method is proposed that creates a personal cough model of the primary subject using limited number of cough samples; the model is used by the automatic cough detection to verify whether the identified coughs match the personal pattern and belong to the primary subject. A Gaussian mixture model is trained using audio features from cough to implement the subject verification method; novel cough embeddings are learned using neural networks and integrated into the model to further improve the prediction accuracy. We analyze the performance of the method using our cough dataset collected by a smart phone in a clinical study. Population in the dataset involves subjects categorized of healthy or patients with COPD or Asthma, with the purpose of covering a wider range of pulmonary conditions. Cross-subject validation on a diverse dataset shows that the method achieves an average error rate of less than 10%, using a personal cough model generated by only 5 coughs from the primary subject.
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http://dx.doi.org/10.1109/EMBC44109.2020.9176835DOI Listing
July 2020

CoughGAN: Generating Synthetic Coughs that Improve Respiratory Disease Classification

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:5682-5688

Despite the prevalence of respiratory diseases, their diagnosis by clinicians is challenging. Accurately assessing airway sounds requires extensive clinical training and equipment that may not be easily available. Current methods that automate this diagnosis are hindered by their use of features that require pulmonary function tests. We leverage the audio characteristics of coughs to create classifiers that can distinguish common respiratory diseases in adults. Moreover, we build on recent advances in generative adversarial networks to augment our dataset with cleverly engineered synthetic cough samples for each class of major respiratory disease, to balance and increase our dataset size. We experimented on cough samples collected with a smartphone from 45 subjects in a clinic. Our CoughGAN-improved Support Vector Machine and Random Forest models show up to 76% test accuracy and 83% F1 score in classifying subjects' conditions between healthy and three major respiratory diseases. Adding our synthetic coughs improves the performance we can obtain from a relatively small unbalanced healthcare dataset by boosting the accuracy over 30%. Our data augmentation reduces overfitting and discourages the prediction of a single, dominant class. These results highlight the feasibility of automatic, cough-based respiratory disease diagnosis using smartphones or wearables in the wild.
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http://dx.doi.org/10.1109/EMBC44109.2020.9175597DOI Listing
July 2020

Estimation of the Lung Function Using Acoustic Features of the Voluntary Cough.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:4491-4497

Spirometry test, a measure of the patient's lung function, is the gold standard for diagnosis and monitoring of chronic pulmonary diseases. Spirometry is currently being done in hospital settings by having the patients blow the air out of their lungs forcefully and into the spirometer's tubes under the supervision and constant guidance of clinicians. This test is expensive, cumbersome and not easily applicable to every-day monitoring of these patients. The lung mechanism when performing a cough is very similar to when spirometry test is done. That includes a big inhalation, air compression and forceful exhalation. Therefore, it is reasonable to assume that obstruction of lung airways should have a similar effect on both cough features and spirometry measures. This paper explores the estimation of lung obstruction using cough acoustic features. A total number of 3695 coughs were collected from patients from 4 different conditions and 4 different severity categories along with their lung function measures in a clinical setting using a smartphone's microphone and a hospital-grade spirometry lab. After feature-set optimization and model hyperparameter tuning, the lung obstruction was estimated with MAE (Mean Absolute Error) of 8% for COPD and 9% for asthma populations. In addition to lung obstruction estimation, we were able to classify patients' disease state with 91% accuracy and patients' severity within each disease state with 95% accuracy.Clinical Relevance- This enables effort-independent estimation of lung function spirometry parameters which could potentially lead to passive monitoring of pulmonary patients.
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http://dx.doi.org/10.1109/EMBC44109.2020.9175986DOI Listing
July 2020

A Comprehensive Approach for Classification of the Cough Type.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:208-212

Identifying the presence of sputum in the lung is essential in detection of diseases such as lung infection, pneumonia and cancer. Cough type classification (dry/wet) is an effective way of examining presence of lung sputum. This is traditionally done through physical exam in a clinical visit which is subjective and inaccurate. This work proposes an objective approach relying on the acoustic features of the cough sound. A total number of 5971 coughs (5242 dry and 729 wet) were collected from 131 subjects using Smartphone. The data was reviewed and annotated by a novel multi-layer labeling platform. The annotation kappa inter-rater agreement score is measured to be 0.81 and 0.37 for 1st and 2nd layer respectively. Sensitivity and specificity values of 88% and 86% are measured for classification between wet and dry coughs (highest across the literature).
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http://dx.doi.org/10.1109/EMBC44109.2020.9175345DOI Listing
July 2020

Diagnosis and surgical treatment of bilateral ureteral calculi, hydronephrosis, pyometra, pyocolpos, vestibulovaginal stenosis, and imperforate hymen in a dog: A rare critical case report.

J Adv Vet Anim Res 2020 Sep 29;7(3):384-390. Epub 2020 Jun 29.

Department of Veterinary Surgery, Royal Animal Medical Center, Jungnang-gu, Seoul, Republic of Korea.

Objective: Bilateral ureteral calculi, hydronephrosis, pyometra, pyocolpos, vestibulovaginal stenosis, and imperforate hymen in a dog are uncommon and can be difficult to diagnose. The aim of this article is to report diagnostic challenges and successful surgical treatment of this rare event and the long-term outcomes.

Materials And Methods: A 5-year-old, spayed (partial ovariohysterectomy) female dog was primarily diagnosed with bilateral hydronephrosis and ureter obstruction due to urolithiasis along with pyometra. The urolith was removed carefully by the right-side ureterectomy, an appropriate ureteral stent was inserted from the bladder to the right kidney, and then, a vasectomy and hysterectomy were performed. The dog improved and was discharged. However, 50 days after surgery, pyocolpos due to imperforate hymen and vestibulovaginal stenosis were diagnosed and surgically corrected, and the ureteral stent was removed because the ureter had completely healed.

Results: During the first admission, serum biochemistry results revealed the increased blood urea nitrogen (5.9 mg/dl), creatinine (116.2 mg/dl), amylase (1,345 U/l), and lipase (141 U/l) values. After surgical correction, all parameters returned to normal. However, 50 days after surgery, the C-reactive protein concentration (143 mg/l) and white blood cell level increased (18.4 × 10/l). After a second surgical correction, the dog recovered fully within 10 days, and no postoperative complications were observed during the follow-up of 6 months.

Conclusion: This report provides diagnostic assistance and surgical treatment options for a complex urogenital case. Careful examination during puberty is recommended to prevent the associated complications of this disorder.
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http://dx.doi.org/10.5455/javar.2020.g432DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7521814PMC
September 2020

Correction to: Exploring Epidemiological Behavior of Novel Coronavirus (COVID-19) Outbreak in Bangladesh.

SN Compr Clin Med 2020 Sep 15. Epub 2020 Sep 15.

Department of Computer and Communication Engineering (CCE), Patuakhali Science and Technology University (PSTU), Dumki, Patuakhali 8602 Bangladesh.

[This corrects the article DOI: 10.1007/s42399-020-00477-9.].
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http://dx.doi.org/10.1007/s42399-020-00517-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7490110PMC
September 2020

Synthesis of Cu-Doped [email protected] CuO Nanostructured Electrode Materials by a Solution Process for High-Performance Electrochemical Pseudocapacitors.

ACS Omega 2020 Sep 27;5(35):22356-22366. Epub 2020 Aug 27.

Department of Energy and Materials, Konkuk University, Chungju 27478, Korea.

Cu-doped MnO and Mn-doped CuO ([email protected]) mixed oxides with isolated phases together with pristine MnO (MO) and CuO (CO) have been synthesized by a simple solution process for applications in electrochemical supercapacitors. The crystallographic, spectroscopic, and morphological analyses revealed the formation of all of the materials with good crystallinity and purity with the creation of rhombohedral-shaped MO and CMO and a mixture of spherical and rod-shaped CO and MCO nanostructures. The ratio of CMO and MCO in the optimized [email protected] was 2:1 with the Cu and Mn dopants percentages of 12 and 15%, respectively. The MO-, CO-, and [email protected] carbon cloth (CC) electrodes delivered the specific capacitance ( ) values of 541.1, 706.7, and 997.2 F/g at 5 mV/s and 413.4, 480.5, and 561.1 F/g at 1.3 A/g, respectively. This enhanced value of [email protected] with an energy density and a power density of 78.0 Wh/kg and 650.0 W/kg, respectively, could be attributed to the improvement of electrical conductivity induced by the dopants and the high percentage of oxygen vacancies. This corroborated to a decrease in the optical band gap and charge-transfer resistance ( ) of [email protected] at the electrode/electrolyte interface compared to those of MO and CO. The net enhancement of the Faradaic contribution induced by the redox reaction of the dopant and improved surface area was also responsible for the better electrochemical performance of [email protected] The [email protected]/CC electrode showed high electrochemical stability with a loss of only ca. 4.7%. This research could open up new possibilities for the development of doped mixed oxides for high-performance supercapacitors.
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http://dx.doi.org/10.1021/acsomega.0c02740DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7482310PMC
September 2020

Exploring Epidemiological Behavior of Novel Coronavirus (COVID-19) Outbreak in Bangladesh.

SN Compr Clin Med 2020 Aug 26:1-9. Epub 2020 Aug 26.

Department of Computer and Communication Engineering (CCE), Patuakhali Science and Technology University (PSTU), Dumki, Patuakhali 8602 Bangladesh.

Globally, there is an obvious concern about the fact that the evolving 2019-nCoV coronavirus is a worldwide public health threat. The appearance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China at the end of 2019 triggered a major global epidemic, which is now a major community health issue. As of August 13, 2020, according to the Institute of Epidemiology, Disease Control and Research (IEDCR), Bangladesh has reported 269,095 confirmed cases between 8 March and 13 August 2020, with > 1.30% of mortality rate and > 57% of recovery rate. COVID-19 outbreak is evolving so rapidly in Bangladesh; therefore, the availability of epidemiological data and its sensible analysis are essential to direct strategies for situational awareness and intervention. This article presents an exploratory data analysis approach to collect and analyze COVID-19 data on epidemiological outbreaks based on the first publicly available COVID-19 Daily Dataset of Bangladesh. Various publicly open data sources on the outbreak of COVID-19 provided by the IEDCR, World Health Organization (WHO), Directorate General of Health Services (DGHS), and Ministry of Health and Family Welfare (MHFW) of Bangladesh have been used in this research. Visual exploratory data analysis (V-EDA) techniques have been followed in this research to understand the epidemiological characteristics of COVID-19 outbreak in different districts of Bangladesh between 8 March 2020 and 13 August 2020 and these findings were compared with those of other countries. In all, this is extremely important to promptly spread information to understand the risks of this pandemic and begin containment activities in the country.
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http://dx.doi.org/10.1007/s42399-020-00477-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7447972PMC
August 2020

COVID faster R-CNN: A novel framework to Diagnose Novel Coronavirus Disease (COVID-19) in X-Ray images.

Inform Med Unlocked 2020 1;20:100405. Epub 2020 Aug 1.

Department of Computer Science and Engineering (CSE), Military Institute of Science and Technology (MIST), Mirpur Cantonment, Dhaka, 1216, Bangladesh.

COVID-19 or novel coronavirus disease, which has already been declared as a worldwide pandemic, at first had an outbreak in a large city of China, named Wuhan. More than two hundred countries around the world have already been affected by this severe virus as it spreads by human interaction. Moreover, the symptoms of novel coronavirus are quite similar to the general seasonal flu. Screening of infected patients is considered as a critical step in the fight against COVID-19. As there are no distinctive COVID-19 positive case detection tools available, the need for supporting diagnostic tools has increased. Therefore, it is highly relevant to recognize positive cases as early as possible to avoid further spreading of this epidemic. However, there are several methods to detect COVID-19 positive patients, which are typically performed based on respiratory samples and among them, a critical approach for treatment is radiologic imaging or X-Ray imaging. Recent findings from X-Ray imaging techniques suggest that such images contain relevant information about the SARS-CoV-2 virus. Application of Deep Neural Network (DNN) techniques coupled with radiological imaging can be helpful in the accurate identification of this disease, and can also be supportive in overcoming the issue of a shortage of trained physicians in remote communities. In this article, we have introduced a VGG-16 (Visual Geometry Group, also called OxfordNet) Network-based Faster Regions with Convolutional Neural Networks (Faster R-CNN) framework to detect COVID-19 patients from chest X-Ray images using an available open-source dataset. Our proposed approach provides a classification accuracy of 97.36%, 97.65% of sensitivity, and a precision of 99.28%. Therefore, we believe this proposed method might be of assistance for health professionals to validate their initial assessment towards COVID-19 patients.
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http://dx.doi.org/10.1016/j.imu.2020.100405DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7395610PMC
August 2020

Identification and activity of monoamine oxidase in the orb-weaving spider Larinioides cornutus.

Gen Comp Endocrinol 2020 12 19;299:113580. Epub 2020 Aug 19.

Department of Biological Sciences, East Tennessee State University, Johnson City, TN 37601, United States.

Monoamine oxidase (MAO) is a mitochondrial membrane-bound enzyme that catalyzes the oxidative deamination of monoamines in a wide array of organisms. While the enzyme monoamine oxidase has been studied extensively in its role in moderating behavior in mammals, there is a paucity of research investigating this role in invertebrates, where the latter utilizes this enzyme in a major pathway to degrade monoamines. There is especially a dismal lack of information on how MAO influences activity in invertebrates, particularly in account of the circadian cycle. Previous studies revealed MAO degrades serotonin and norepinephrine in arachnids, but did not investigate other critically important compounds like octopamine. Larinioides cornutus is a species of orb-weaving spider that exhibits diel fluctuations in behavior, specifically levels of aggression. The monoamines octopamine and serotonin have been shown to influence aggressive behaviors in L. cornutus, thus this species was used to investigate if MAO is a potential site of regulation throughout the day. Not only did gene expression of MAO orthologs and MAO activity fluctuate at different times of day, but the enzymatic activity was substrate-specific producing a higher level of degradation of octopamine as compared to serotonin in vitro. This study further supports evidence that MAO has an active role in monoamine inactivation in invertebrates and provides a first look at how MAO ultimately may be regulating behavior in an invertebrate.
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http://dx.doi.org/10.1016/j.ygcen.2020.113580DOI Listing
December 2020
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