The regulation of necrosis in mycobacterial lesions

Tuberculosis is characterised by necrotic immunopathology in the lesions and tuberculin skin-test sites (Koch phenomenon), and persistence of the organisms. Previous work from this laboratory suggested that immunotherapy with killed M. vaccae can reduce this tissue damage, and that TNF plays a role in its pathogenesis. The purpose of this thesis was to study the mechanism of action of M. vaccae in man and in a rodent model. Sera from patients in Kuwait who received M.vaccae or saline were screened by immunoblotting and laser scanning to seek changes in the pattern of mycobacterial antigens recognised, and by an immunoassay for changes in levels of agalactosyl IgG (a correlate of T cell-dependent immunopathology). A fall in agalactosyl IgG and a selective increase in antibody to a 30kDa antigen was noted. This antigen was identified as the fibronectin-binding secreted protein, and was purified to homogeneity from culture filtrate by column chromatography. The increased antibody binding was confirmed by ELISA. A murine model of TNF-induced tissue damage in sites of T cell-mediated inflammation was then devised, to mimic aspects of the Koch phenomenon using the 30 KDa and the 65 KDa heat shock protein (hsp). This model allows simultaneous assessment of both swelling and haemorrhage caused by injection of TNF into delayed hypersensitivity (DTH) sites. It was found that some DTH responses evoked by mycobacterial antigens are as sensitive to subsequently injected TNF as are sites prepared by injection of LFS (local Shwartzman reaction) though for mycobacterial antigens CD8+ T cells are required. This phenomenon also involved CR3+ cells, phagocytic cells, complement, and perhaps IL-6, and could be diminished by PAF inhibitors and a prostaglandin analogue. However, by testing different immunisation schedules using M. vaccae, it was discovered that it is also possible to evoke DTH responses in which subsequent injection of TNF has no effect at all. The heat shock proteins may play a role in this effect. The implications of the existence of two qualitatively different types of DTH response and the consequences of neutralizing TNF, using an anti-murine TNF antibody, in a murine tuberculosis model are discussed in relation to the immunopathology of tuberculosis and autoimmune diseases such as rheumatoid arthritis where mycobacterial antigens, cytokines and T cell dependent inflammation are important

Characteristics of red light running violations in urban areas in Tabuk, Kingdom of Saudi Arabia

AbstractThis paper aims to assess the characteristics of red light violations in Tabuk city of the Kingdom of Saudi Arabia. The paper also analyzes the effect of intersection characteristics, such as geometric design, control system and location, on number of violations. Data on traffic characteristics and violations, intersection geometric design (road width, number of lanes, speed) were collected at 38 intersections in Tabuk using video cameras. Statistical analysis reveals that number of approaches, speed, road width, speed on cross road, and width of cross road significantly affects red light violation. Regression analysis implies that road width, red time and speed are the most important factors affecting red light violation

Peaceful modes of defining international boundary disputes with particular reference to the practice of the Kingdom of Saudi Arabia and its neighbouring states regarding the settlement of their land boundary disputes

[From the introduction]The main purpose of this thesis is to analyse and assess the practice of Saudi Arabia and its neighbouring states with regard to the settlement of their land boundary disputes in the light of the principles of international law. To this end, it will first try to discuss the evolution of the Saudi boundaries along with the acquisition of the Saudi territory and to determine the basic factors responsible for the land boundary disputes between the Kingdom of Saudi Arabia and its neighbouring states. Secondly, it will evaluate the peaceful methods which have been applied by Saudi Arabia and its neighbours in settling their boundary disputes. This study, however, does not extend to examine the settlement of Saudi Arabia's maritime boundaries with its neighbouring states. The reason for this is that the thesis focuses on international land boundaries, and to include maritime boundaries would broaden the subject and make it difficult to provide a proper discussion within the constraints of a PhD thesis. This is especially so as there are 10 states which share maritime boundaries with Saudi Arabia

Measurement and Study of Radioactive Radon Gas Concentrations in the Selected Samples of River Hilla / Iraq

In this study measuring concentrations of radon in water for Hilla province of Babylon (100 Km) south of capital Baghdad. Was chosen as the water River Hilla study by 88 sample from 22 regions by using the electronic radon detector RAD7, and the average concentration of radon in the Hilla River (0.103 ± 0.057) Bq.L-1 , where the highest value (0.181 ± 0.07) Bq.L-1 and the lowest value (0.036 ± 0.05) Bq.L-1 and effective dose for the current study of the importance Has been chosen this subject of .1-human exposure to radon was (0.45) mSv.yof water in human life and living, and the lack of previous studies in the study area.Keywords: radon concentrations, River Hilla , Annual effective dose, RAD7

Comparative analysis of computer-vision and BLE technology based indoor navigation systems for people with visual impairments

Background: Considerable number of indoor navigation systems has been proposed to augment people with visual impairments (VI) about their surroundings. These systems leverage several technologies, such as computer-vision, Bluetooth low energy (BLE), and other techniques to estimate the position of a user in indoor areas. Computer-vision based systems use several techniques including matching pictures, classifying captured images, recognizing visual objects or visual markers. BLE based system utilizes BLE beacons attached in the indoor areas as the source of the radio frequency signal to localize the position of the user. Methods: In this paper, we examine the performance and usability of two computer-vision based systems and BLE-based system. The first system is computer-vision based system, called CamNav that uses a trained deep learning model to recognize locations, and the second system, called QRNav, that utilizes visual markers (QR codes) to determine locations. A field test with 10 blindfolded users has been conducted while using the three navigation systems. Results: The obtained results from navigation experiment and feedback from blindfolded users show that QRNav and CamNav system is more efficient than BLE based system in terms of accuracy and usability. The error occurred in BLE based application is more than 30% compared to computer vision based systems including CamNav and QRNav. Conclusions: The developed navigation systems are able to provide reliable assistance for the participants during real time experiments. Some of the participants took minimal external assistance while moving through the junctions in the corridor areas. Computer vision technology demonstrated its superiority over BLE technology in assistive systems for people with visual impairments. - 2019 The Author(s).Scopu

Household travel and tour-based behaviour: a case study from Saudi Arabia

The present study utilises the activity-based approach to investigate the nature and determinants of travel behaviour, and to reach a better understanding of travel complexity within households in an Islamic cultural environment. The main objectives of this study are, firstly to describe and explain the variation of behaviour between a sample of Saudi households and, secondly, to identify the likely response to specific transport policies. Results suggest that household head attributes (occupation, education and income), household socio-economic characteristics (car ownership, availability of a chauffeur, number of female students, number of females in employment and household size), and neighbourhood characteristics (density, accessibility to work) significantly influenced the choice of work tour type. The usefulness of applying tour-based analysis and its strength in showing interactions between household members' activities were confirmed in this study. Tour-based models revealed that Saudi households' travel activities were highly dependent on the household head, who is mainly responsible for serving household members' travel needs. In-depth interviews showed concerns about children's safety and security, lack of public and, in particular, school transport, ignorance of female travel needs, and car oriented neighbourhood design were main reasons for the high dependency on the car and its role as the dominant travel mode within Saudi cities. Interviewees were presented with five transport related policies to investigate their likely impact on households' travel behaviour. Interviewees agreed that the proposed policies would decrease car dependency and increase the travel independence of household members. Change in travel behaviour, in response to proposed policies, as identified by interviewees included decreased travel complexity (simpler tours), change in tour mode (more walking and public transport tours), and change in tour time. The study estimated a reduction in car trips generated by households as a result of introducing policies aimed to shift dependent groups (i.e. children and females) towards independence through walking and use of public transpor

The pathogen recognition sensor, NOD2, is variably expressed in patients with pulmonary tuberculosis

Background: NOD2, an intracellular pathogen recognition sensor, modulates innate defences to muropeptides derived from various bacterial species, including Mycobacterium tuberculosis (MTB). Experimentally, NOD2 attenuates two key putative mycobactericidal mechanisms. TNF-alpha synthesis is markedly reduced in MTB-antigen stimulated-mononuclear cells expressing mutant NOD2 proteins. NOD2 agonists also induce resistance to apoptosis, and may thus facilitate the survival of MTB in infected macrophages. To further define a role for NOD2 in disease pathogenesis, we analysed NOD2 transcriptional responses in pulmonary leucocytes and mononuclear cells harvested from patients with pulmonary tuberculosis (PTB).Methods: We analysed NOD2 mRNA expression by real-time polymerase chain-reaction in alveolar lavage cells obtained from 15 patients with pulmonary tuberculosis and their matched controls. We compared NOD2 transcriptional responses, in peripheral leucocytes, before and after anti-tuberculous treatment in 10 patients. In vitro, we measured NOD2 mRNA levels in MTB-antigen stimulated-mononuclear cells.Results: No significant differences in NOD2 transcriptional responses were detected in patients and controls. In some patients, however, NOD2 expression was markedly increased and correlated with toll-like-receptor 2 and 4 expression. In whole blood, NOD2 mRNA levels increased significantly after completion of anti-tuberculosis treatment. NOD2 expression levels did not change significantly in mononuclear cells stimulated with mycobacterial antigens in vitro.Conclusion: There are no characteristic NOD2 transcriptional responses in PTB. Nonetheless, the increased levels of NOD2 expression in some patients with severe tuberculosis, and the increases in expression levels within peripheral leucocytes following treatment merit further studies in selected patient and control populations