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The genetics of nicotine dependence:Relationship to Pancreatic cancer

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World Journal of Gastroenterology 2006年第46期12卷 7433-7439页

作者： Stewart L MacLeod Parimal chowdhury Department of Pediatrics University of Arkansas for Medical Sciences and Arkansas Children's Hospital Research Institute Arkansas Center for Birth Defects Research and Prevention Little Rock AR United States Department of Physiology University of Arkansas for Medical Sciences Little Rock AR United States

Smoking of tobacco products continues to be a major cause of worldwide health problems. Epidemiological studies have shown that tobacco smoking is the greatest risk factor for the development of pancreatic cancer. Smokers who are able to quit smoking can reduce their risk of pancreatic cancer by nearly 50% within two years, however, their risk of developing pancreatic cancer remains higher than that of non-smokers for 10 years. Nicotine is the major psychoactive substance in tobacco, and is responsible for tobacco dependence and addiction. Recent evidence suggests that individuals have genetically based differences in their ability to metabolize nicotine, as well as genetic differences in the psychological reward pathways that may influence individual response to smoking initiation, dependence, addiction and cessation. Numerous associations have been reported between smoking behavior and genetic polymorphisms in genes that are responsible for nicotine metabolism. In addition, polymorphisms in genes that encode neurotransmitters and transporters that function in psychological reward pathways have been implicated in differences in smoking behavior. However, there is a large degree of between-study variability that demonstrates the need for larger, well-controlled casecontrol studies to identify target genes and deduce mechanisms that account for the genetic basis of interindividual differences in smoking behavior. Understanding the genetic factors that increase susceptibility to tobacco addiction may result in more effective tobacco cessation programs which will, in turn, reduce the incidence of tobacco related disease, including pancreatic cancer.

关键词： Smoking Pancreatic cancer Nicotine dependence Genetics Polymorphism Nicotine metabolism

Deposition behavior and tribological properties of diamond-like carbon coatings on stainless steels via chemical vapor deposition

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1335-1343页

作者： Labani Mustafi M.M.Rahman Mohammad Nur E Alam Al Nasim Mohammad Asaduzzaman chowdhury M.H.Monir School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Engineering RMIT UniversityMelbourneVictoria 3001Australia Dhaka University of Engineering and Technology Gazipur 1707Bangladesh

A systematic investigation was carried out to observe the deposition rate of a diamond-like carbon(DLC) coating on two stainless steel substrates by chemical vapor deposition(CVD). The objective of this research is to study the deposition behavior of the DLC coating and its tribological properties in different combinations of methane(CH_4) and nitrogen, which were used as precursor gases. The results reveal that the deposition rate increases with increasing CH_4 content up to 50 vol%. The hardness of the DLC-deposited layer also increases while the friction coefficient decreases with increasing CH_4 gas content up to 50% in the precursor gas mixture.

关键词： diamond-like carbon chemical vapor deposition methane and nitrogen gas mixtures deposition rate hardness friction coefficient

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Improved systemic half-life of glucagon-like peptide-1-loaded carbonate apatite nanoparticles in rats

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World Journal of Diabetes 2022年第8期13卷 613-621页

作者： Nabilah Ibnat Rahela Zaman Mohammad Borhan Uddin Ezharul chowdhury Chooi Yeng Lee School of Medicine and Health Sciences Monash University MalaysiaSubang Jaya 47500SelangorMalaysia School of Pharmacy Monash University MalaysiaSubang Jaya 47500SelangorMalaysia

BACKGROUND Glucagon-like peptide-1(GLP1)is an endogenous peptide that regulates blood glucose *** its susceptibility to rapid metabolic degradation limits its therapeutic *** To prepare GLP1-encapsulated nanosize particle with controlled release property to improve the systemic half-life of *** GLP1 nanoparticles were prepared by complexation of GLP1 with carbonate apatite nanoparticles(CA NPs).The physicochemical properties of the CA NPs,the effects of GLP1-loaded CA NPs on cell viability,and the systemic bioavailability of GLP1 after CA NPs administration were *** The GLP1-loaded CA NPs was within 200 nm in size and stable in fetal bovine *** formulation did not affect the viability of human cell lines suggesting that the accumulation of CA NPs in target tissues is *** Sprague Dawley rats,the plasma GLP1 Levels as measured from the GLP1-loaded CA NPs-treated rats,were significantly higher than that of the control rats and free GLP1-treated rats at 1 h post-treatment(P<0.05),and the level remained higher than the other two groups for at least 4 *** The GLP1-loaded CA NPs improved the plasma half-life of *** systemic bioavailability of GLP1 is longer than other GLP1 nanoparticles reported to date.

关键词： Glucagon-like peptide-1 Metabolic syndrome Nanoparticles Plasma half-life Rat

Microstrip Patch Antenna with an Inverted T-Type Notch in the Partial Ground for Breast Cancer Detections

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1301-1322页

作者： Nure Alam chowdhury Lulu Wang Md Shazzadul Islam Linxia Gu Mehmet Kaya Department of Biomedical Engineering and Science Florida Institute of TechnologyMelbourneFL 32901USA Biomedical Device Innovation Center Shenzhen Technology UniversityShenzhen518118China Department of Electrical and Computer Engineering International Islamic University MalaysiaJalan GombakSelangor53100Malaysia

This study designs a microstrip patch antenna with an inverted T-type notch in the partial ground to detect tumorcells inside the human *** size of the current antenna is small enough(18mm×21mm×1.6mm)todistribute around the breast *** operating frequency has been observed from6–14GHzwith a minimumreturn loss of−61.18 dB and themaximumgain of current proposed antenna is 5.8 dBiwhich is flexiblewith respectto the size of *** the distribution of eight antennas around the breast phantom,the return loss curveswere observed in the presence and absence of tumor cells inside the breast phantom,and these observations showa sharp difference between the presence and absence of tumor *** simulated results show that this proposedantenna is suitable for early detection of cancerous cells inside the breast.

关键词： Antenna microwave wideband cancer breast phantom tumor detection

A software-based approach in designing a rooftop bifacial PV system for the North Hall of Residence, IUT

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Clean Energy 2021年第3期5卷 403-422页

作者： Abdullah Al Mehadi Misbahul Alam chowdhury Mirza Muntasir Nishat Fahim Faisal Md Minhajul Islam Islamic University of Technology Board-BazarGazipurDhaka-1704Bangladesh

Bifacial rooftop photovoltaic panels appear to be an excellent means of power generation in this era of urbanization,especially for land-limited countries like *** paper presents a software-based approach to design and simulate a bifacial solar-panel-based energy model on the rooftop of the North Hall of Residence of the Islamic University of Technology,*** vertically mounted model investigates the feasibility and applicability of such an energy model in a university residence,situated in a load-shedding-prone ***,three prominent software platforms,namely PVSOL,PVsyst and System Advisor Model(SAM),are brought into action and rigorous simulations are performed for three different orientations;promising outcomes are observed in terms of annual energy yield,bifacial gain(BG)and consumption coverage of the grid and PV *** annual energy demand of the North Hall is~444733.5 *** three orientations can generate annually 92508.62,94643.48 and 86758.94 kWh,***,it is evident that the proposed orientations can supply almost 19-21%of the site’s annual *** BG analysis shows an overall increase in energy gain of 13%,15.6%and 6%for Orientation-1,Orientation-2 and Orientation-3,respectively.A rigorous comparative analysis and deviation analysis among the software results has been accomplished to gain more insight into the feasibility of the proposed ***,we have focused on a detailed software-based estimation of energy production for different orientations of the PV panels,considering several factors,which will provide prior knowledge and assessment before going for hardware implementation in the future.

关键词： bifacial solar PV panel PVSOL PVsyst SAM annual energy yield bifacial gain

Magnetic properties of Sn-substituted Ni-Zn ferrites synthesized from nano-sized powders of NiO, ZnO, Fe2O3, and SnO2

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Chinese Physics B 2017年第7期26卷 377-382页

作者： M A Ali M M Uddin M N I Khan F U Z chowdhury S M Hoque S I Liba Department of Physics Chittagong University of Engineering and Technology (CUET) Materials Science Division Atomic Energy Center

A series of Ni0.6-x/2Zn0.4-x/2SnxFe2O4(x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.3)(NZSFO) ferrite composities have been synthesized from nano powders using a standard solid state reaction technique. The spinel cubic structure of the investigated samples has been confirmed by x-ray diffraction(XRD). The magnetic properties such as saturation magnetization(Ms),remanent magnetization(Mr), coercive field(Hc), and Bohr magneton(μ) are calculated from the hysteresis loops. The value of Msis found to decrease with increasing Sn content in the samples. This change is successfully explained by the variation of A-B interaction strength due to Sn substitution in different sites. The compositional stability and quality of the prepared ferrite composites have also been endorsed by the fairly constant initial permeability(μ’) over a wide range of frequency. The decreasing trend of μ’ with increasing Sn content has been observed. Curie temperature TChas been found to increase with the increase in Sn content. A wide spread frequency utility zone indicates that the NZSFO can be considered as a good candidate for use in broadband pulse transformers and wide band read-write heads for video recording. The composition of x = 0.05 shows unusual results and the possible reason is also mentioned with the established formalism.

关键词： magnetic properties saturation magnetization permeability Curie temperature

The Association between Vitamin D Deficiency and Developing COVID-19 Related Serious Illnesses—A Systematic Review and Meta-Analysis

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Advances in Infectious Diseases 2023年第3期13卷 452-467页

作者： Abdul Kabir chowdhury Faculty of Health and Social Care University of Chester Chester UK

Background: Coronavirus is rapidly transmitted and highly infectious, and it is also associated with high morbidity and mortality but no drugs have been recognised as being effective;therefore, it is necessary to protect against serious illnesses with an intrinsic protection mechanism. In addition, Vitamin D enhances the intrinsic protection mechanism. Purpose: This study aims to systematically review and conduct a meta-analysis to determine if vitamin D deficiency is associated with the development of severe COVID-19 illness, providing crucial insights into the potential impact of vitamin D on disease outcomes. Methods: This study is conducted through systematic reviews and meta-analysis while following well-designed research questions. Literature searches are performed according to PRISMA guidelines with inclusion and exclusion criteria through the electronic database PubMed, CINAHL and Google Scholar. All data for meta-analysis were performed using RevMan 5.4. The software program was used for blending the statistical data and deriving the cumulative result of the intervention on concluding outcomes of interest. To analyze dichotomous data, the Mantel-Haenszel method was performed, and an odds ratio was conducted for outcome evaluation with 95% confidence interval. Results: The meta-analysis showed that there is statistically significant (P Conclusion: This study indicated that Vitamin D deficiency is associated with the development of COVID-19 related serious illnesses. Also, it is highly recommended to do more randomised control trials for the establishment of this topic strongly.

关键词： COVID-19 Coronavirus Vitamin D Vitamin D Deficiency ICU Mortality

Unilateral neuropathic arthropathy of the shoulder secondary to syringomyelia: Diagnostic challenges

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World Journal of Clinical Cases 2015年第12期3卷 1017-1020页

作者： Partha Pratim Chakraborty Saumik Datta Sayantan Ray Rana Bhattacharjee Subhankar chowdhury Department of Endocrinology Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital

Neuropathic arthropathy of the shoulder is a rare disorder characterized by joint degeneration, and is associated with loss of sensory innervation. Syringomyelia is a disease in which fluid-containing cavities(syrinxes) form within the spinal cord. Here, we report a case of neuropathic arthropathy of the shoulder secondary to syringomyelia in a 40-year-old woman. X-rays of the left shoulder revealed damage to bone and joint architecture. Blood tests indicated vitamin D deficiency and secondary hyperparathyroidism. Magnetic resonance imaging of the cervical spine showed a large syrinx from the second cervical spine to the second dorsal spine. Although neuropathic arthropathy is uncommon, it should be considered in cases of unexplained pain, discomfort, or limited range of motion of the affected joint. Symptoms related to the affected joint may precede or overshadow neurological deficits. Appropriate radiological examinations and diagnoses are imperative to prevent misdiagnosis or undetected bone and joint disorders.

关键词： Neuropathic arthropathy Charcot shoulder Syringomyelia Magnetic resonance imaging Vitamin D deficiency

Antibacterial mechanism with consequent cytotoxicity of different reinforcements in biodegradable magnesium and zinc alloys: A review

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Journal of Magnesium and Alloys 2023年第9期11卷 3038-3058页

作者： chowdhury Ahmed Shahed Faiz Ahmad Ebru Günister Farhana Mohd Foudzi Saad Ali Khurshid Malik Wan Sharuzi Wan Harun Department of Mechanical Engineering Universiti Teknologi PETRONAS(UTP)32610Seri IskandarPerakMalaysia Faculty of Engineering and Natural Sciences Department of Mechanical EngineeringIstanbul Health and Technology UniversityIstanbulTurkey Department of Mechanical and Manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Faculty of Mechanical&Automotive Engineering Technology Universiti Malaysia Pahang26600 PekanPahangMalaysia

Benefits achieved by the biodegradable magnesium(Mg) and zinc(Zn) implants could be suppressed due to the invasion of infectious microbial, common bacteria, and fungi. Postoperative medications and the antibacterial properties of pure Mg and Zn are insufficient against biofilm and antibiotic-resistant bacteria, bringing osteomyelitis, necrosis, and even death. This study evaluates the antibacterial performance of biodegradable Mg and Zn alloys of different reinforcements, including silver(Ag), copper(Cu), lithium(Li), and gallium(Ga). Copper ions(Cu^(2+)) can eradicate biofilms and antibiotic-resistant bacteria by extracting electrons from the cellular structure. Silver ion(Ag^(+)) kills bacteria by creating bonds with the thiol group. Gallium ion(Ga^(3+)) inhibits ferric ion(Fe^(3+)) absorption, leading to nutrient deficiency and bacterial death. Nanoparticles and reactive oxygen species(ROS) can penetrate bacteria cell walls directly, develop bonds with receptors, and damage nucleotides. Antibacterial action depends on the alkali nature of metal ions and their degradation rate, which often causes cytotoxicity in living cells. Therefore, this review emphasizes the insight into degradation rate, antibacterial mechanism, and their consequent cytotoxicity and observes the correlation between antibacterial performance and oxidation number of metal ions.

关键词： Biodegradable materials Biomedical implants Antibacterial mechanism Cytotoxicity Reactive oxygen species

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