Identification Of Antigenic Proteins Of Salmonella Enterica Subspecies Enterica Serovar Typhi In Sera Of Patients With Acute Typhoid Fever

Demam kepialu disebabkan oleh sejenis bakteria Gram-negatif, Salmonella enterica subspecies enterica serovar Typhi (S. Typhi). Penyakit ini berleluasa di seluruh dunia terutamanya di negara-negara yang mundur atau sedang membangun. Oleh sebab kekurangan biopenanda yang sensitif dan spesifik di pasaran, diagnosis demam kepialu masih kekal sebagai satu masalah kepada pengamal kesihatan. Ini mungkin kerana biopenanda tersebut dikenalpasti dalam keadaan in vitro menggunakan kultur mikrobiologi. Infeksi adalah satu proses dinamik dan penghasilan antigen bergantung kepada cabaran persekitaran yang dihadapi oleh bakteria. Dalam kajian ini, serum pesakit demam kepialu digunakan sebagai sumber antigen in vivo kerana ia mengandungi produk fisiologi daripada perumah dan bakteria yang dihasilkan ketika infeksi. Namun demikian, kewujudan protein manusia dalam kuantiti yang banyak (HAPs) di dalam serum pesakit akan menghalang pengesanan protein antigenik yang wujud dalam kuantiti yang sedikit (LAPs) dan berat molekul rendah, yang mungkin mengandungi biopenanda yang berkaitan dengan penyakit tertentu. Serum daripada pesakit demam kepialu (PTFS) dan serum daripada manusia normal (PNHS) diproses menggunakan 2 kaedah, iaitu 1) afiniti kromatografi untuk memisahkan albumin dan immunoglobulin G (IgG) daripada serum, dan 2) ultraturasan membran untuk memisahkan protein berat molekul lebih daripada 100 kDa daripada serum. Typhoid fever is caused by a Gram-negative bacteria, Salmonella enterica subspecies enterica serovar Typhi (S. Typhi). It is a worldwide disease infecting mostly the under-developed and developing countries. Due to a lack of sensitive and specific biomarkers available in the market, diagnosis of typhoid fever remains a problem for the clinician. This may be due to the fact that these biomarkers were identified using pure microbiological cultures grown in in vitro conditions. Infection is a dynamic process and the expression of antigens depend on the environmental challenges faced by the bacteria. This study used serum as a source of in vivo antigens as it contains physiological signatures from both host and bacterial origin that are produced in vivo during infection. However, the presence of high abundance proteins (HAPs) in human serum masks the detection of low abundance proteins (LAPs) and low molecular weight proteins, which contain candidate protein biomarkers relevant to a particular disease state. Pooled Typhoid Fever Sera (PTFS) and Pooled Normal Human Sera (PNHS) were subjected to 2 different serum separation methods, i.e. 1) affinity chromatography to remove albumin and immunoglobulin G (IgG), and 2) membrane ultrafiltration to remove proteins with molecular weights greater than 100 kDa. These protein preparations were then subjected to 2 protein analysis methods, i.e. 1) SDS-PAGE-Western blot, and 2) 2D-PAGE-Western blot

Immunomodulation resulting of helminth infection could be an opportunity for immunization against tuberculosis and mucosal pathogens

Approximately, 10 million new tuberculosis (TB) cases were reported in 2020, of which 12% were among children (1). It is estimated that one-quarter of the world population (around 2 billion) is latently infected by Mycobacterium tuberculosis (Mtb) and 5-10% of these individuals will develop active TB (ATB) (1). Infections caused by soil-transmitted helminths (STH) and schistosomes affect about 1.5 billion and 250 million people, respectively, worldwide (2). Children and pregnant women are the population groups with the highest risk of infection by those parasites (3)

An overview of out-of-step protection in power systems

Power system is subjected to an extensive variety of little or bigger disturbance to the system during the operation. The power system that designed as one of the main requirement is to survive from the larger type of disturbances like faults. The power swing in certain system is the variation in three phase power flow in the power system. This paper mainly discussed the power swing and distance relay and the effect of the power swing on the distance relay and demonstrate about the basic power system stability and power swing phenomena. Moreover, out of step protection and detection applications are revised as well. At the end, the paper also demonstrated the past study of out of step application of TNB 275 KV network

Development of titanium dioxide nanoparticles/nanosolution for photocatalytic activity

Biological and chemical contaminants by man-made activities have been serious global issue. Exposure of these contaminants beyond the limits may result in serious environmental and health problem. Therefore, it is important to develop an effective solution that can be easily utilized by mankind. One of the effective ways to overcome this problem is by using titanium dioxide (TiO2). TiO2 is a well-known photocatalyst that widely used for environmental clean-up due to its ability to decompose organic pollutant and kill bacteria. Although it is proven TiO2 has an advantage to solve this concern, its usefulness unfortunately is limited only under UV light irradiation. Therefore, the aim of this work was to investigate the potential of TiO2 that can be activated under visible light by the incorporation of metal ions (Fe, Ag, Zr and Ag-Zr). In this study, sol-gel method was employed for the synthesis of metal ions incorporated TiO2. XRD analysis revealed that all samples content biphasic anatase-brookite TiO2 of size 3 nm to 5 nm. It was found that the incorporation of these metal ions did not change the morphology of TiO2 but the crystallinity and optical properties were affected. The crystallinity of anatase in the biphasic TiO2 was found to be decreased and favored brookite formation. PL analysis showed metal ions incorporation suppressed the recombination of electron-hole pairs while the band gap energy of TiO2 (3.2 eV) was decreased by the incorporation of Fe (2.46 eV) and Ag (2.86 eV). Among this incorporation, Ag-Zr incorporated TiO2 showed highest performance for methyl orange degradation (93%) under fluorescent xxv light irradiation for 10 h. This follows by Zr-TiO2 (82%), Fe-TiO2 (75%) and Ag�TiO2 (43%). Meanwhile, the highest antibacterial performance was exhibited by Ag�TiO2. TEM images showed that E.coli bacterium was killed within 12 h after treated with Ag-TiO2. The results obtained from the fieldwork study established that Ag-Zr incorporation have excellent performances for VOC removal and antibacterial test. The VOC content after treated with Ag-Zr-TiO2 fulfilled the Industry Code of Practice on Indoor Air Quality 2010 which is lower than 3 ppm. In addition, the percentage of microbes also found to be decrease around 45 % within 5 days of monitoring

Role of Interferons in the Development of Diagnostics, Vaccines, and Therapy for Tuberculosis

Tuberculosis (TB) is an airborne infection caused by Mycobacterium tuberculosis (Mtb). About one-third of the world’s population is latently infected with TB and 5–15% of them will develop active TB in their lifetime. It is estimated that each case of active TB may cause 10–20 new infections. Host immune response to Mtb is influenced by interferon- (IFN-) signaling pathways, particularly by type I and type II interferons (IFNs). The latter that consists of IFN-γ has been associated with the promotion of Th1 immune response which is associated with protection against TB. Although this aspect remains controversial at present due to the lack of established correlates of protection, currently, there are different prophylactic, diagnostic, and immunotherapeutic approaches in which IFNs play an important role. This review summarizes the main aspects related with the biology of IFNs, mainly associated with TB, as well as presents the main applications of these cytokines related to prophylaxis, diagnosis, and immunotherapy of TB

Pulmonary non-tuberculous mycobacterial infections: current state and future management

Currently, there is a trend of increasing incidence in pulmonary non-tuberculous mycobacterial infections (PNTM) together with a decrease in tuberculosis (TB) incidence, particularly in developed countries. The prevalence of PNTM in underdeveloped and developing countries remains unclear as there is still a lack of detection methods that could clearly diagnose PNTM applicable in these low-resource settings. Since non-tuberculous mycobacteria (NTM) are environmental pathogens, the vicinity favouring host-pathogen interactions is known as important predisposing factor for PNTM. The ongoing changes in world population, as well as socio-political and economic factors, are linked to the rise in the incidence of PNTM. Development is an important factor for the improvement of population well-being, but it has also been linked, in general, to detrimental environmental consequences, including the rise of emergent (usually neglected) infectious diseases, such as PNTM. The rise of neglected PNTM infections requires the expansion of the current efforts on the development of diagnostics, therapies and vaccines for mycobacterial diseases, which at present, are mainly focused on TB. This review discuss the current situation of PNTM and its predisposing factors, as well as the efforts and challenges for their control

Selection and validation of emotional videos: Dataset of professional and amateur videos that elicit basic emotions

This article describes the process of selecting a collection of professional and amateur videos that elicit five basic emotions (i.e., happiness, fear, disgust, anger, and sadness) and validating these videos in three groups of participants (i.e., Chinese from China, Chinese from Malaysia, and Bumiputera from Malaysia). In the video selection phase, professional videos, which were Western movie trailers, were selected from IMDb (Internet Movie Database) and amateur videos were selected from YouTube. The researchers selected videos that display five basic emotions, identified the time frames with the strongest display of emotion, and rated the emotional intensity of each video on a 5-point Likert scale. After the initial stage of selection, two other researchers performed an emotion recognition task by watching the videos without audio to ensure that the emotions can be elicited without understanding the language. This data was used to refine the final selection of 20 professional videos and 20 amateur videos. In the video validation phase, 30 participants were asked to identify and rate the intensity of emotion felt. This article includes a description of the video selection method, a detailed list of the videos selected, and participants' responses and ratings of emotional intensity for the 40 videos

Identification and Characterization of Mycobacterium tuberculosis Beijing Genotype Strain SBH163, Isolated in Sabah, Malaysia

This is a report on the whole-genome sequence of Mycobacterium tuberculosis strain SBH163, which was isolated from a patient in the Malaysian Borneo state of Sabah. This report provides insight into the molecular characteristics of an M. tuberculosis Beijing genotype strain related to strains from Russia and South Africa

DNA markers for tuberculosis diagnosis

Tuberculosis (TB), caused by Mycobacterium tuberculosis complex (MTBC), is an infectious disease with more than 10.4 million cases and 1.7 million deaths reported worldwide in 2016. The classical methods for detection and differentiation of mycobacteria are: acid-fast microscopy (Ziehl-Neelsen staining), culture, and biochemical methods. However, the microbial phenotypic characterization is time-consuming and laborious. Thus, fast, easy, and sensitive nucleic acid amplification tests (NAATs) have been developed based on specific DNA markers, which are commercially available for TB diagnosis. Despite these developments, the disease remains uncontrollable. The identification and differentiation among MTBC members with the use of NAATs remains challenging due, among other factors, to the high degree of homology within the members and mutations, which hinders the identification of specific target sequences in the genome with potential impact in the diagnosis and treatment outcomes. In silico methods provide predictive identification of many new target genes/fragments/regions that can specifically be used to identify species/strains, which have not been fully explored. This review focused on DNA markers useful for MTBC detection, species identification and antibiotic resistance determination. The use of DNA targets with new technological approaches will help to develop NAATs applicable to all levels of the health system, mainly in low resource areas, which urgently need customized methods to their specific conditions

Influences of neurotransmission-related genetic polymorphisms on depression, anxiety and stress

Over 10% of the world population suffer from mental disorders. In particular, depression causes about 800,000 suicide cases annually, while anxiety is the most common mental disorder. Stresses from work, life, and health have been identified as the common triggers for the two mental disorders. Eventhough mental disorders are treatable and validated tools are available to diagnose, many individuals are left untreated due to different factors, such as a lack of trained personnel and stigma. Neuroscience research indicates that mental disorders could be hereditary, where genes involved in determining behavioural variants. Disturbance in brain communication, resulting from abnormalities in neurogenesis, neurotransmission, and enzymatic degradation, have led to negative emotional states. This mini-review will highlight some important genes in the neurotransmitter systems and explore the relationship between gene polymorphisms and emotional states (i.e., depression, anxiety, and stress). The genes that will be discussed in this mini-review include brain-derived neurotrophic factor (BDNF) which is involved in neuron development, serotonin-transporter-linked polymorphic region (5-HTTLPR) and 5- hydroxytryptamine receptor 1A (5-HT1A) which are involved in serotonin neurotransmitter action potential propagation, and monoamine oxidase A (MAOA) and catechol-O-methyltransferase (COMT), which are involved in neurotransmitter catabolism