Characterisation of immune responses to mycobacterial infections in a murine model of type 2 diabetes

Tuberculosis (TB) caused by Mycobacterium tuberculosis remains one of the major global health threats. The disease is responsible for significant morbidity and mortality, with an estimated one third of the world's population having latent TB infections (LTBI). Reactivation of LTBI occurs in immunocompromised individuals. Diabetes mellitus (DM) is a condition that impairs host defence, leading to higher morbidity and mortality in individuals with TB. The global burden of DM is unprecedented with 425 million people living with diabetes in 2017 and 4 million diabetes-associated deaths. Type 2 diabetes (T2D) comprises more than 90% of the global diabetes incidence and is attributed to genetic, environment and life style factors. Obesity, caused mostly by a combination of sedentary life style and consumption of an energy-dense diet rich in refined carbohydrate and fat, is considered a leading cause of the global increase of T2D. The resurgent interest in TB-T2D co-morbidity is due to the slow reduction in global TB incidence and the rapid escalation of T2D particularly in TB endemic areas. Epidemiological studies have found a strong correlation of T2D with increased TB susceptibility, reactivation of LTBI and treatment failure, however the underlying mechanisms for this are unclear. Non-tuberculous mycobacterial (NTM) infections are also increasing in individuals with diabetes in comparison to the general population. Among the NTM species, Mycobacterium fortuitum is a leading cause of skin and soft tissue infections and capable of causing severe pulmonary infections. There is no data available on T2D-M. fortuitum co-morbid conditions. A few studies have investigated the reason for increased TB susceptibility in diabetics although the findings are often contradictory. Animal model studies designed to investigate immune dysregulation in diabetes/mycobacterium co-morbidity have typically used streptozotocin induced type 1 diabetic murine models rather than models of T2D. Hence, characterisation of a T2D murine model that incorporates the Western diet and accurately models the clinical features of human T2D is highly desirable. Such a model is also required to investigate the immunological dysfunction in host-mycobacterial co-morbid infections and thus allow the development of therapeutic and preventative strategies. The first Aim of this study was to characterise a diet-induced diabetic mouse model of T2D for subsequent mycobacterial infection studies. Male C57BL/6 mice were used for all experiments with groups receiving either an energy-dense diet (EDD) for a period of 30 weeks to induce diabetes or a standard rodent diet (SRD) for the same time period. The metabolic and biochemical parameters including body weight, fasting blood glucose (FBG) level, glucose tolerance test (GTT), glycated haemoglobin (HbA1c) level, urine albumin, creatinine and albumin creatinine ratio (ACR) were assessed after 25 and 30 weeks. Visceral adipose tissue, liver, pancreas and kidney from mice were analysed using a variety of histological stains and image analysis techniques. Body weight gain was increased in EDD fed mice compared to SRD fed control animals. After both 25 and 30 weeks, EDD fed mice had a significantly higher FBG levels, glucose intolerance and HbA1c levels compared to controls. Analysis of urine biochemical parameters demonstrated higher microalbumin, lower creatinine and higher ACR in EDD fed mice compared to controls. Histological examination of visceral adipose tissue, liver and pancreas revealed adipocyte hypertrophy, hepatic steatosis and a compensatory pancreatic islet hyperplasia, respectively in mice fed the EDD compared to controls. Mesangial matrix thickening within the glomeruli, thickening of the Bowman's capsules and glomerular size were increased in the kidneys of EDD fed mice compared to controls. These results suggested that feeding an EDD for 30 weeks can induce a T2D phenotype in mice. The metabolic, biochemical and histological findings demonstrated a chronic hyperglycaemic state due to insulin resistance. The urine biochemical parameters together with histological observations also confirmed renal damage which is one of the common complications of diabetes in humans. The second Aim of this research was to investigate macrophage phagocytic function in vitro. In initial experiments, peritoneal exudate macrophages (PEM), resident peritoneal macrophages (RPM) and alveolar macrophages (AM) isolated from diabetic and control mice were assessed for the respective abilities to phagocytose mycolic acid coated beads and induce cytokines. Subsequently, the phagocytic uptake, bacterial killing capacity and cytokine secretion of these macrophages was assessed by co-culture with M. fortuitum, M. bovis (BCG) and M. tuberculosis (H37Rv). Results demonstrated that uptake of the mycolic acid coated beads was reduced significantly in PEM, RPM and AM from diabetic mice compared to controls. There were no significant differences in the production of cytokines from these cells following co-culture with the beads. However, there was a significant reduction in mycobacterial uptake and killing in both RPM and AM from the diabetic mice compared to controls. Furthermore, there was a reduction in TNF-α, MCP-1, IL-6 and IL-1β production by both RPM and AM from diabetic mice compared to controls during co-culture. These findings indicated that the uptake, killing and cytokine production were impaired in macrophages from diabetic mice compared to controls. The final Aim of this study was to investigate the susceptibility of diabetic and control mice to M. fortuitum, M. bovis (BCG) and M. tuberculosis (H37Rv) infections by evaluating animal survival, organ bacterial loads, tissue pathology and organ cytokine levels during the course of high- or low-dose intravenous infections. Diabetic mice showed higher mortality compared to controls following challenge with a high-dose of all mycobacteria. Following low-dose challenge with all mycobacteria species, the bacillary burden was higher in spleen, liver and lungs of diabetic mice compared to controls at 14 and 30/35 days post infection. Estimation of the number and size of inflammatory granuloma-like lesions in the liver, revealed increased inflammation, with higher loads of acid-fast bacilli in diabetic mice compared to controls. Furthermore, the total area of inflammation observed in the lungs of diabetic mice was significantly higher than controls. Assessment of tissue cytokines demonstrated an overall lower production of TNF-α, MCP-1, IL-6 and IL-1β in the liver and lungs of diabetic mice compared to controls although an opposite trend was observed in the spleen. The overall production of IL-12, IL-2 and IFN-γ was reduced in the spleen, liver and lungs of diabetic mice compared to controls. In summary, this thesis describes the influence of an EDD on the induction of diabetes in a mouse model and the increased susceptibility of these diabetic animals to mycobacterial infection. It was found that the EDD has the potential to induce overt clinical features of T2D in mice that closely mirror the pathology observed in human T2D patients. Investigation of antimycobacterial immune responses (in vitro and in vivo) showed that the uptake, killing and cytokine production (TNF-α, MCP-1, IL-6 and IL-1β) by macrophages was impaired in T2D. A higher bacterial load and high numbers of inflammatory lesions were observed in the organs of diabetic mice which is also indicative of impairment of macrophage phagocytic function. Decreased production of pro-inflammatory cytokines including IL-12, IL-2 and IFN-γ in diabetic mice indicated that T helper 1 cells mediated responses in mycobacterial infections maybe delayed or impaired. This immune defect in diabetics may ultimately lead to delayed or defective granuloma formation. Our results also suggest the possibility of a breakdown of the granuloma due to the persistent hyperglycaemia that occurs in diabetes. The current study has demonstrated that antimycobacterial immunity was dysregulated in T2D mice which is one of the key reasons for increased mycobacterial susceptibility. Moreover, the diet-induced murine model of T2D that we have developed can be used for future in depth studies of host-mycobacterial susceptibility. The model can also be used to investigate other infections that are exacerbated by diabetes

Chilling Effects on Freedom of Speech and Expression in the Digital Age: A Comparative Study on the Role of the US and Indian Supreme Court

The First Amendment to the United States Constitution is an essential part of the Bill of Rights The amendment prohibits making of any law respecting an establishment of religion obstructing the free exercise of religion infringing on the freedom of speech infringing on the freedom of the press interfering peoples assembling rights in a peaceful manner or prohibiting the petitioning for a governmental remedy of grievances The guarantees of this Bill of Rights were subject to the limitation imposed by the free speech and press provisions of the First Amendment to the US Constitution as interpreted and applied by the Supreme Court and other courts The United States and India are the largest democratic country and almost have similar free speech provisions in their Constitutions This Article is intended to present the free speech provisions of the American and Indian Constitution as a basic fundamental right of human being It is also to be examined that what is the role of Supreme Court in interpreting the freedom of speech and expression provisions The study also tries to incorporate the comparison between the looms of both countries as far as freedom of speech is disturbe

Legal Aspects for Peaceful Uses of the Sea under UNCLOS Convention

Peace has no alternative but to promote. Peace is addressed in every sphere of human life. Human life with peace gives rise to perpetuity of existing flora and fauna. In the past absence of law and sovereignty a growing number of cross-exploitation conflicts that may include the following: negligent navigation that damages or destroys communication cables, the warming of the seawater used for cooling functions of a nuclear power plant preventing its use for fish farming purposes, an oil spill on the high seas polluting beaches that are essential for tourism in the coastal zone. These activities destroy our natural climate and it changes sea level, ocean acidification, ocean stratification, coral bleaching, changing species distributions and other biological changes to sea. Peaceful exploitation of the world’s oceans and their resources in an era of scientific and technical revolution is one of today’s urgent global problems. No discipline can come to fruition without peace. They supported the inclusion of the wording “peaceful uses of the seas” into the new convention as a fundamental principle governing the activities of all states in relation to the exploitation of the world’s oceans and resources

Silence is the Language of God and Source of Strength: Exploring the Hidden Benefits of Silence

Silent is a beautiful powerful boost of positive energy and it is an important aspect of worship Our mind is moving towards past and future Bringing mindfulness into the present time during our materialistic society of hectic lives silent evolved as a relief mode for relaxation and happiness World Health Organization and the European Commission s Joint Research Centre concluded that a steady dose of noise pollution could lead to higher blood pressure and fatal heart attacks It was the result of the research found that high rates of cholesterol and hypertension in individuals regularly exposed to loud noises at work In this situation silence can actually stimulate new cell growth in the brain improve memory and release tension in the brain and body In fact two minutes of silence is more effective in relieving physical tension than listening to relaxing musi

Understanding Masculinity and Sexual Harassment for Sustainable Development

It is an important phenomenon to draw a common understanding of sexual harassment in a national and international concept. This applies in particular the determination to reach an agreement around a common concept definition of sexual harassment, irrespective of race, culture, and situation, form of exposure, colour, national context, and so onwards. Bangladesh has a strong legal framework to reduce violence against women; however, the law and reality are different. Women in this society are generally perceived as mothers and wives and not as equal working partners. So, women’s education has a significant impact on family income and development and the males in household activities are also absent and women’s activities are entertaining guests, preparing food, and cooking. The deep-rooted gender inequalities and discrimination makes women helpless also in the higher education level. Sexual harassment in public universities had the highest proportion of women that reported ‘never telling anyone’ about their experience of harassment by friends or teachers. This research would like to find out the ways of breaking masculinity and gender-based violence in the higher educational institution, which is authorized under the relevant disciplinary rules to take action in case of misconduct. This article will also explore the protection mechanism from sexual harassment and how the right to education and work with dignity is recognized as basic human rights in higher education levels

Compliance of IAS-30: A Case Study on the Specialized Banks of Bangladesh

This Journal aimed at scrutinizing the prevailing accounting standard for the banks and find out the extent of compliance by them. To find out the degree of compliance the study has gone through the annual reports of all the sample banks. Very naturally it is hoped that all of them are required to comply with the standard to uphold the stakeholders' interest. Banking industry's nature of operation is totally different .Recognizing this aspect some specific IAS (International Accounting Standard) have been prescribed for them. One of which is IAS 30(Disclosures requirements for banks and similar financial institutions). Although IAS-30 has been superseded by IFRS (International Financial Reporting Standard)-7, ICAB (Institute of Chartered Accountants of Bangladesh) prescribed to comply with IFRS-7 from on or after 1st January, 2010. Hence compliance of IAS-30 is of importance here. Keywords: IAS, IFRS, Specialized banks, compliance

Effects on two semi-circular wall heaters in a rectangular enclosure containing trapezoidal heated obstacle in presence of MHD

A computational study has been done to illustrate the effects on two semi-circular wall heaters placed in a mixed convection rectangular enclosure containing trapezoidal heated obstacle in presence of magnetic field. The upper wall moves with a velocity in the positive x-direction. Trapezoidal obstacle is located in the middle of the cavity and two semi-circular wall heaters are placed at the bottom wall with fixed distance between them. These two horizontal walls are kept adiabatic except two semi-circular wall heaters. Two vertical walls are kept at low temperature and concentration and the trapezoidal obstacle and two semi-circular walls are kept at high temperature and concentration. Finite element method is used to solve governing equations. The present analysis is performed for parameters such as Hartmann number, Buoyancy ratio and Richardson number. The effects of aforesaid parameters are explored on the fluid flow and temperature at two semi-circular wall heaters. The results show that heat transfer rate along right semi-circular wall heater dominates the left semi-circular wall heater with the increase of both the parameters Hartmann number and Buoyancy ratio

CFD modelling of turbulent combustion and heat transfer

This thesis is concerned with the development and implementation of computational fluid dynamics (CFD) based prediction methodologies for turbulent reacting flows with principal application to turbulent diffusion flame combustors. Numerical simulation of combustion problems involve strong coupling between chemistry, transport and fluid dynamics. The works accomplished in this study can be separated mainly into three distinct areas: i) assessment of the performance of turbulent combustion models and to implement suitable submodels for combustion and flame behaviour into CFD code; ii) Conducting CFD modelling of turbulent diffusion flames, radiation heat loss from combustion and flame zones; and iii) modelling of pollutants like NOx (oxides of nitrogen), identification of the effect of radiation heat loss on NOx formation. The combustion models studied are the flame-sheet, equilibrium, eddy break-up and laminar flamelet models. An in-house CFD code is developed and combustion models are implemented. The basic numerical issues involving the discretisation schemes are addressed by employing three discretisation schemes namely, hybrid, power law and TVD (total variation diminishing) schemes. The combustion of different fuels ranging from simple H2/N2 and CO/H2/N2 to complex CH4/H2 are investigated for different inlet velocities and boundary conditions. The performances of the combustion models are analysed for these fuels. The configurations used for the validation and assessment of the combustion models are co-flowing jet flames and bluff body burner stabilized flames. The high quality experimental databases available from Sandia national laboratories, the University of Sydney and other reported measurements are used for the purpose of evaluating the combustion models. The predicted results demonstrate the effects of turbulent mixing and the effects of chemical reactions on the combustion models. The calculations show that all the combustion models like flame-sheet and equilibrium models are found to be inadequate even for the near equilibrium flames. Although the equilibrium chemistry model is capable of predicting the mixture fraction, temperature and concentrations of major and minor species, the predictive accuracy is found to be inadequate specially, when compared to the experimental data. In situations, where finite rate chemistry effects are important the laminar flamelet model is a good choice. The key contributions of this thesis are as follows: 1) Modification of in-house CFD code for turbulent reacting flow and development of CFD based iterative scheme for the turbulent diffusion flames to account for radiation heat loss from combustion and flame zones. 2) Thorough assessment of turbulent combustion modelling techniques for different cases of diffusion flames, demonstration of the importance of differential diffusion in the flamelet modelling of combustion and comprehensive validation 3) Demonstration of the importance of radiation heat loss in the modelling of turbulent combustion, implementation of radiation modelling in the three cases of diffusion flames and comprehensive validation of CFD based combustion radiation results. 4) Development of modelling strategy for the pollutants like oxides of nitrogen (NOx), implementation of NOx modelling in the different flames cases and identified the effect of radiation heat loss on NOx formation. The works addressed in this thesis are presented with the applications to turbulent diffusion flame combustors. However, these works can easily be extended to the industrial applications and applied to a large variety of other challenging domains.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

改良型ダブルメディエーターシステムを用いる細胞内NADHのモニタリングによる電気化学的細胞生存活性評価法

富山大学・ 富生命博甲第141号・Md. Abdul Alim・2022/03/23公表論文Mohammad Abdul ALIM, Minoru SUGA, Hiroaki SHINOHARA, Rapid and Highly Sensitive Electrochemical Technique for Cell Viability Assay via Monitoring of Intracellular NADH with New Double Mediator System, Electrochemistry, 2021, 89 巻, 6 号, p. 579-584, 公開日 2021/11/05, [早期公開] 公開日 2021/08/19, Online ISSN 2186-2451, Print ISSN 1344-3542, https://doi.org/10.5796/electrochemistry.21-00088, https://www.jstage.jst.go.jp/article/electrochemistry/89/6/89_21-00088/_article/-char/ja富山大