scholarly journals REVIEW ARTICLE: AMEBIASIS MOLECULAR PATHOGENESIS DEVELOPMENT

2019 ◽  
Vol 3 (2) ◽  
pp. 6
Author(s):  
Nurlina Muliani ◽  
Hotimah Masdan Salim

Amebiasis is one of the gastrointestinal tract infection disease caused by Entamoeba histolytica ,a parasitic protozoan. Amebiasis is the second disease, caused by parasite, that leading cause of death after malaria. Infection occurs through faecal-oral route and after ingestion a contaminated food and beverages by human faeces. The pathogenesis of E. histolytica can be classified into 3 processes, i.e: death of host cell, inflammation, and parasitic invasion. The recent years, a molecularly amebiasis pathogenesis has been developed, i.e: adherence, phagocytosis, tropogocytosis of host cell and how the parasites can survive and attack host cells so it can cause an infection in humans. Molecular development is an important thing to be considered in the selection of amebiasis therapy.

2013 ◽  
Vol 210 (5) ◽  
pp. 905-915 ◽  
Author(s):  
Joana Tavares ◽  
Pauline Formaglio ◽  
Sabine Thiberge ◽  
Elodie Mordelet ◽  
Nico Van Rooijen ◽  
...  

Malaria infection starts when the sporozoite stage of the Plasmodium parasite is injected into the skin by a mosquito. Sporozoites are known to traverse host cells before finally invading a hepatocyte and multiplying into erythrocyte-infecting forms, but how sporozoites reach hepatocytes in the liver and the role of host cell traversal (CT) remain unclear. We report the first quantitative imaging study of sporozoite liver infection in rodents. We show that sporozoites can cross the liver sinusoidal barrier by multiple mechanisms, targeting Kupffer cells (KC) or endothelial cells and associated or not with the parasite CT activity. We also show that the primary role of CT is to inhibit sporozoite clearance by KC during locomotion inside the sinusoid lumen, before crossing the barrier. By being involved in multiple steps of the sporozoite journey from the skin to the final hepatocyte, the parasite proteins mediating host CT emerge as ideal antibody targets for vaccination against the parasite.


2021 ◽  
Author(s):  
Luana G. Morão ◽  
Lívia R. Manzine ◽  
Angélica Luana C. Barra ◽  
Lívia Oliveira D. Clementino ◽  
Raíssa F. Gutierrez ◽  
...  

AbstractStructural biology projects are highly dependent on the large-scale expression of soluble protein and, for this purpose, heterologous expression using bacteria or yeast as host systems are usually employed. In this scenario, some of the parameters to be optimized include (i) those related to the protein construct, such as the use of a fusion protein, the choice for an N-terminus fusion/tag or a C-terminus fusion/tag; (ii) those related to the expression stage, such as the concentration and selection of inducer agent and temperature expression and (iii) the choice of the host system, which includes the selection of a prokaryotic or eukaryotic cell and the adoption of a strain. The optimization of some of the parameters related to protein expression, stage (ii), is straightforward. On the other hand, the determination of the most suitable parameters related to protein construction requires a new cycle of gene cloning, while the optimization of the host cell is less straightforward. Here, we evaluated a scalable approach for the screening of host cells for protein expression in a structural biology pipeline. We evaluated six Escherichia coli strains looking for the best yield in soluble protein expression using the same strategy for protein construction and gene cloning. For the genes used in this experiment, the Arctic Express (DE3) strain resulted in better yields of soluble proteins. We propose that screening of host cell/strain is feasible, even for smaller laboratories and the experiment as proposed can easily be scalable to a high-throughput approach.


2020 ◽  
Author(s):  
Hilje M. Doekes ◽  
Glenn A. Mulder ◽  
Rutger Hermsen

AbstractCommunication based on small signalling molecules is widespread among bacteria. Recently, such communication was also described in bacteriophages. Upon infection of a host cell, temperate phages of the Bacillus subtilis-infecting SPbeta group induce the secretion of a phage-encoded signalling peptide, which is used to inform the lysis-lysogeny decision in subsequent infections: the phages produce new virions and lyse their host cell when the signal concentration is low, but favour a latent infection strategy, lysogenising the host cell, when the signal concentration is high. Here, we present a mathematical model to study the ecological and evolutionary dynamics of such viral communication. We show that a communication strategy in which phages use the lytic cycle early in an outbreak (when susceptible host cells are abundant) but switch to the lysogenic cycle later (when susceptible cells become scarce) is favoured over a bet-hedging strategy in which cells are lysogenised with constant probability. However, such phage communication can evolve only if phage-bacteria populations are regularly perturbed away from their equilibrium state, so that acute outbreaks of phage infections in pools of susceptible cells continue to occur. Our model then predicts the selection of phages that switch infection strategy when half of the available susceptible cells have been infected.


2020 ◽  
Vol 16 (6) ◽  
pp. 891-899 ◽  
Author(s):  
Wissam Zam

Probiotics are viable microorganisms widely used for their claimed beneficial effects on the host health. A wide number of researchers proved that the intake of probiotic bacteria has numerous health benefits which created a big market of probiotic foods worldwide. The biggest challenge in the development of these products is to maintain the viability of bacterial cells during the storage of the product as well as throughout the gastrointestinal tract transit after consumption, so that the claimed health benefits can be delivered to the consumer. Different approaches have been proposed for increasing the resistance of these sensitive microorganisms, including the selection of resistant strains, incorporation of micronutrients, and most recently the use of microencapsulation techniques. Microencapsulation has resulted in enhancing the viability of these microorganisms which allows its wide use in the food industry. In this review, the most common techniques used for microencapsulation of probiotics will be presented, as well as the most usual microcapsule shell materials.


Author(s):  
Neeraj Singh ◽  
Shweta Rai ◽  
Sankha Bhattacharya

Background: About two-third of new drugs reveal low solubility in water due to that; it becomes difficult for formulation scientists to develop oral solid dosage forms with a pharmaceutically acceptable range of therapeutic activity. In such cases, S-SMEEDS are the best carrier used universally for the delivery of hydrophobic drugs. SEDDS were also used, but due to its limitations, S-SMEDDS used widely. These are the isotropic mixtures of oils, co-solvents, and surfactants. S-SMEDDS are physically stable, easy to manufacture, easy to fill in gelatin capsules as well as improves the drug bioavailability by releasing the drug in the emulsion form to the gastrointestinal tract and make smooth absorption of the drug through the intestinal lymphatic pathway. Methods: We took on the various literature search related to our review, including the peer-reviewed research, and provided a conceptual framework to that. Standard tools are used for making the figures of the paper, and various search engines are used for the literature exploration.In this review article the author discussed the importance of S-SMEDDS, selection criteria for excipients, pseudo-ternary diagram, mechanism of action of S-SMEDDS, solidification techniques used for S-SMEDDS, Characterization of SEDDS and S-SMEDDS including Stability Evaluation of both and future prospect concluded through recent findings on S-SMEDDS on Cancer as well as a neoteric patent on S-SMEDDS Results: Many research papers discussed in this review article, from which it was found that the ternary phase diagram is the most crucial part of developing the SMEDDS. From the various research findings, it was found that the excipient selection is the essential step which decides the strong therapeutic effect of the formulation. The significant outcome related to solid-SMEDDS is less the globule size, higher would be the bioavailability. The adsorption of a solid carrier method is the most widely used method for the preparation of solid-SMEDDS. After review of many patents, it is observed that the solid-SMEDDS have a strong potential for targeting and treatment of a different type of Cancer due to their property to enhance permeation and increased bioavailability. Conclusion: S-SMEEDS are more acceptable pharmaceutically as compare to SEDDS due to various advantages over SEDDS viz stability issue is prevalent with SEDDS. A number of researchers had formulated S-SMEDDS of poorly soluble drugs and founded S-SMEDDS as prospective for the delivery of hydrophobic drugs for the treatment of Cancer. S-SMEEDS are grabbing attention, and the patentability on S-SMEDDS is unavoidable, these prove that S-SMEEDS are widely accepted carriers. These are used universally for the delivery of the hydrophilic drugs and anticancer drugs as it releases the drug to the gastrointestinal tract and enhances the systemic absorption. Abstract: Majority of active pharmaceutical ingredients (API) shows poor aqueous solubility, due to that drug delivery of the API to the systemic circulation becomes difficult as it has low bioavailability. The bioavailability of the hydrophobic drugs can be improved by the Self-emulsifying drug delivery system (SEDDS) but due to its various limitations, solid self-micro emulsifying drug delivery systems (S-SMEDDS) are used due to its advantages over SEDDS. S-SMEDDS plays a vital role in improving the low bioavailability of poorly aqueous soluble drugs. Hydrophobic drugs can be easily loaded in these systems and release the drug to the gastrointestinal tract in the form of fine emulsion results to In-situ solubilisation of the drug. In this review article the author's gives an overview of the solid SMEDSS along with the solidification techniques and an update on recent research and patents filled for Solid SMEDDS.


Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 60
Author(s):  
Juan Vélez ◽  
Zahady Velasquez ◽  
Liliana M. R. Silva ◽  
Ulrich Gärtner ◽  
Klaus Failing ◽  
...  

Cryptosporidium parvum is an apicomplexan zoonotic parasite recognized as the second leading-cause of diarrhoea-induced mortality in children. In contrast to other apicomplexans, C.parvum has minimalistic metabolic capacities which are almost exclusively based on glycolysis. Consequently, C. parvum is highly dependent on its host cell metabolism. In vivo (within the intestine) infected epithelial host cells are typically exposed to low oxygen pressure (1–11% O2, termed physioxia). Here, we comparatively analyzed the metabolic signatures of C. parvum-infected HCT-8 cells cultured under both, hyperoxia (21% O2), representing the standard oxygen condition used in most experimental settings, and physioxia (5% O2), to be closer to the in vivo situation. The most pronounced effect of C. parvum infection on host cell metabolism was, on one side, an increase in glucose and glutamine uptake, and on the other side, an increase in lactate release. When cultured in a glutamine-deficient medium, C. parvum infection led to a massive increase in glucose consumption and lactate production. Together, these results point to the important role of both glycolysis and glutaminolysis during C. parvum intracellular replication. Referring to obtained metabolic signatures, we targeted glycolysis as well as glutaminolysis in C. parvum-infected host cells by using the inhibitors lonidamine [inhibitor of hexokinase, mitochondrial carrier protein (MCP) and monocarboxylate transporters (MCT) 1, 2, 4], galloflavin (lactate dehydrogenase inhibitor), syrosingopine (MCT1- and MCT4 inhibitor) and compound 968 (glutaminase inhibitor) under hyperoxic and physioxic conditions. In line with metabolic signatures, all inhibitors significantly reduced parasite replication under both oxygen conditions, thereby proving both energy-related metabolic pathways, glycolysis and glutaminolysis, but also lactate export mechanisms via MCTs as pivotal for C. parvum under in vivo physioxic conditions of mammals.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Nicholas M. Negretti ◽  
Christopher R. Gourley ◽  
Prabhat K. Talukdar ◽  
Geremy Clair ◽  
Courtney M. Klappenbach ◽  
...  

AbstractCampylobacter jejuni is a foodborne pathogen that binds to and invades the epithelial cells lining the human intestinal tract. Maximal invasion of host cells by C. jejuni requires cell binding as well as delivery of the Cia proteins (Campylobacter invasion antigens) to the host cell cytosol via the flagellum. Here, we show that CiaD binds to the host cell protein IQGAP1 (a Ras GTPase-activating-like protein), thus displacing RacGAP1 from the IQGAP1 complex. This, in turn, leads to the unconstrained activity of the small GTPase Rac1, which is known to have roles in actin reorganization and internalization of C. jejuni. Our results represent the identification of a host cell protein targeted by a flagellar secreted effector protein and demonstrate that C. jejuni-stimulated Rac signaling is dependent on IQGAP1.


2021 ◽  
Vol 12 (2) ◽  
pp. 26
Author(s):  
Sebastian Wilk ◽  
Aleksandra Benko

Biopolymers formed into a fibrous morphology through electrospinning are of increasing interest in the field of biomedicine due to their intrinsic biocompatibility and biodegradability and their ability to be biomimetic to various fibrous structures present in animal tissues. However, their mechanical properties are often unsatisfactory and their processing may be troublesome. Thus, extensive research interest is focused on improving these qualities. This review article presents the selection of the recent advances in techniques aimed to improve the electrospinnability of various biopolymers (polysaccharides, polynucleotides, peptides, and phospholipids). The electrospinning of single materials, and the variety of co-polymers, with and without additives, is covered. Additionally, various crosslinking strategies are presented. Examples of cytocompatibility, biocompatibility, and antimicrobial properties are analyzed. Special attention is given to whey protein isolate as an example of a novel, promising, green material with good potential in the field of biomedicine. This review ends with a brief summary and outlook for the biomedical applicability of electrospinnable biopolymers.


2021 ◽  
Vol 9 (5) ◽  
pp. 1015
Author(s):  
Tianyu Zhang ◽  
Xin Gao ◽  
Dongqiang Wang ◽  
Jixue Zhao ◽  
Nan Zhang ◽  
...  

Cryptosporidium parvum is a globally recognized zoonotic parasite of medical and veterinary importance. This parasite mainly infects intestinal epithelial cells and causes mild to severe watery diarrhea that could be deadly in patients with weakened or defect immunity. However, its molecular interactions with hosts and pathogenesis, an important part in adaptation of parasitic lifestyle, remain poorly understood. Here we report the identification and characterization of a C. parvum T-cell immunomodulatory protein homolog (CpTIPH). CpTIPH is a 901-aa single-pass type I membrane protein encoded by cgd5_830 gene that also contains a short Vibrio, Colwellia, Bradyrhizobium and Shewanella (VCBS) repeat and relatively long integrin alpha (ITGA) N-terminus domain. Immunofluorescence assay confirmed the location of CpTIPH on the cell surface of C. parvum sporozoites. In congruence with the presence of VCBS repeat and ITGA domain, CpTIPH displayed high, nanomolar binding affinity to host cell surface (i.e., Kd(App) at 16.2 to 44.7 nM on fixed HCT-8 and CHO-K1 cells, respectively). The involvement of CpTIPH in the parasite invasion is partly supported by experiments showing that an anti-CpTIPH antibody could partially block the invasion of C. parvum sporozoites into host cells. These observations provide a strong basis for further investigation of the roles of CpTIPH in parasite-host cell interactions.


2021 ◽  
Vol 9 (6) ◽  
pp. 1144
Author(s):  
Isabel Marcelino ◽  
Philippe Holzmuller ◽  
Ana Coelho ◽  
Gabriel Mazzucchelli ◽  
Bernard Fernandez ◽  
...  

The Rickettsiales Ehrlichia ruminantium, the causal agent of the fatal tick-borne disease Heartwater, induces severe damage to the vascular endothelium in ruminants. Nevertheless, E. ruminantium-induced pathobiology remains largely unknown. Our work paves the way for understanding this phenomenon by using quantitative proteomic analyses (2D-DIGE-MS/MS, 1DE-nanoLC-MS/MS and biotin-nanoUPLC-MS/MS) of host bovine aorta endothelial cells (BAE) during the in vitro bacterium intracellular replication cycle. We detect 265 bacterial proteins (including virulence factors), at all time-points of the E. ruminantium replication cycle, highlighting a dynamic bacterium–host interaction. We show that E. ruminantium infection modulates the expression of 433 host proteins: 98 being over-expressed, 161 under-expressed, 140 detected only in infected BAE cells and 34 exclusively detected in non-infected cells. Cystoscape integrated data analysis shows that these proteins lead to major changes in host cell immune responses, host cell metabolism and vesicle trafficking, with a clear involvement of inflammation-related proteins in this process. Our findings led to the first model of E. ruminantium infection in host cells in vitro, and we highlight potential biomarkers of E. ruminantium infection in endothelial cells (such as ROCK1, TMEM16K, Albumin and PTPN1), which may be important to further combat Heartwater, namely by developing non-antibiotic-based strategies.


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