DNA vaccination with a plasmid encoding LACK-TSA fusion against Leishmania major infection in BALB/c mice

Vaccination would be the most important strategy for the prevention and elimination of leishmaniasis. The aim of the present study was to compare the immune responses induced following DNA vaccination with LACK (Leishmania analogue of the receptor kinase C), TSA (Thiol-specific-antioxidant) genes alone or LACK-TSA fusion against cutaneous leishmaniasis (CL). Cellular and humoral immune responses were evaluated before and after challenge with Leishmania major (L. major). In addition, the mean lesion size was also measured from 3th week post-infection. All immunized mice showed a partial immunity characterized by higher interferon (IFN)-gamma and Immunoglobulin G (IgG2a) levels compared to control groups (p< 0.05). IFN-gamma/Interleukin (IL)-4 and IgG2a/IgG1 ratios demonstrated the highest IFN-gamma and IgG2a levels in the group receiving LACK-TSA fusion. Mean lesion sizes reduced significantly in all immunized mice compared with control groups at 7th week post-infection (p< 0.05). In addition, there was a significant reduction in mean lesion size of LACK-TSA and TSA groups than LACK group after challenge (p< 0.05). In the present study, DNA immunization promoted Th1 immune response and confirmed the previous observations on immunogenicity of LACK and TSA antigens against CL. Furthermore, this study demonstrated that a bivalent vaccine can induce stronger immune responses and protection against infectious challenge with L. major

Aprendiendo del pasado

In the 90s, the Argentine fishing sector raised the opportunity to open the range to a new exploitation based on natural resources. Fishing went from a semi-industrial activity, of moderate scale, to a large-scale one. Argentine hake was the focus of national and international fishing companies and began to experience excessive pressures. Over the last three decades, the sector has undergone changes: international prices have increased, markets have been opened and consolidated, catching techniques have been perfected, etc. Although for some species a strategy based on individual and transferable catch quotas (ITQs) has been established, to avoid repeating previous catch records, a series of dilemmas persist: the challenge of sustainable exploitation, respecting biological times and affecting ecosystems as little as possible so that the activity can be exploited for future generations. This paper presents the criticisms that still exist on the management of the resource through ITQs. In particular, the interactions between macro, micro and environmental aspects are analyzed, reflecting on the possible deviations from optimal catch paths, incompleteness, and imperfections in the available information.En la década del 90, el sector pesquero argentino planteó la oportunidad de abrir el abanico a una nueva explotación basada en recursos naturales. La pesca pasó de una actividad semi-industrial, de escala moderada, a una de gran escala. La Merluza argentina fue el foco de las empresas pesqueras nacionales e internacionales y comenzó a experimentar presiones excesivas. Durante las últimas tres décadas, el sector ha experimentado cambios: han aumentado los precios internacionales, se han abierto y consolidado mercados, se ha perfeccionado las técnicas de captura, etc. Si bien para algunas especies se instauró una estrategia basada en cuotas individuales y transferibles de captura (CITC), que intenta evitar repetir registros de capturas olímpicas, aún persiste una serie de dilemas: el desafío de una explotación sostenible, respetando los tiempos biológicos y afectando lo menos posible los ecosistemas para que la actividad permita un aprovechamiento para generaciones futuras. En este trabajo se presentan las críticas que todavía existen sobre la gestión del recurso mediante CITC. En particular se analizan las interacciones entre lo macro, la micro y lo ambiental, reflexionando sobre los posibles desvíos de los senderos óptimos de captura, incompletitudes e imperfecciones en la información disponible

Expression of Plasmid Encoded GRA4 Gene of Toxoplasma gondii RH Strain in CHO Eukaryotic Cells

Background: Toxoplasmosis is a common infection all around the world. During pregnancy; it may lead to congenital disorders or abortion in human and animals. Severe damage of toxoplasmosis indicates to require effective vaccine. One of dense granules antigen is GRA4 that secrete from tachyzoite and bradyzoite. GRA4 genome is unique without intron and is one of the major immunogenic proteins from Toxoplasma gondii. Methods: We confirmed the cloning of GRA4 gene into pcDNA3 by restriction enzyme and PCR of GRA4 gene with pcGRA4 plasmids as template. Then with using calcium- phosphate method we transfected the pcGRA4 into CHO (Chinesehamster ovary) cells. The yielded protein was separated by SDS-PAGE and moved by electroblotting to nitrocellulose paper. Results: Result of SDS-PAGE analysis showed the appearance of band approximately 42 kDa which was absent in the negative control, that was able to identify toxoplasmosis antibody IgM+ serum in western blot analysis. Conclusion: pcGRA4 plasmid is able to synthesis of antigenic protein in CHO cells. The ability of pcGRA4 for induction of protective immune response against toxoplasmosis will be evaluated in mouse model

Effects of Vasodepressor vs. Vasopressor Arms of Renin Angiotensin System on Renal Hemodynamic Regulation in Renal Ischemia-Reperfusion Injury; Sex Difference

The exact mechanisms involved in acute renal injury (AKI) due to renal ischemia-reperfusion (IR) are not fully understood, although it has been shown that the renin-angiotensin system (RAS) may play an important role in IR-associated AKI. RAS is considered as one of the most important vasoactive systems of endocrine, paracrine and intracrine, which is important in the physiological regulation of cardiovascular function, blood pressure, fluid and electrolytes balance. This system exerts a set of beneficial or adverse vascular and renal effects. The two main arms of RAS include "ACE, angiotensin II, AT1 receptor" (vasoconstrictor arm) and "ACE2, angiotensin 1-7, AT2 receptor and Mas receptor" (vasodilator arm). IR and its outputs have been reported to be sex-dependent. On the other hand, systemic and local RAS function in the regulation of renal hemodynamics can also be affected by gender. In fact, sex and sex hormones affect sensitivity to angiotensin II and angiotensin 1-7. This review article examines the role of RAS receptors of the new vasopressor arm versus the classic vasopressor arm and their function interference, as well as sex differences and it's influence on renal blood flow in renal IR Injury. © 2022 Isfahan University of Medical Sciences(IUMS). All rights reserved

Comparative Assessment of Induced Immune Responses Following Intramuscular Immunization with Fusion and Cocktail of LeIF, LACK and TSA Genes Against Cutaneous Leishmaniasis in BALB/c Mice

In the present study, we evaluated induced immune responses following DNA vaccine containing cocktail or fusion of LeIF, LACK and TSA genes or each gene alone. Mice were injected with 100 lg of each plasmid containing the gene of insert, plasmid DNA alone as the first control group or phosphate buffer saline as the second control group. Then, cellular and humoral responses, lesion size were measured for all groups. All vaccinated mice induced Th1 immune responses against Leishmania characterized by higher IFN-gamma and IgG2a levels compared with control groups (p<0.05). In addition, IFN-gamma levels increased in groups immunized with fusion and cocktail vaccines in comparison with LACK (p<0.001) and LeIF (p<0.01) groups after challenge. In addition, fusion and cocktail groups produced higher IgG2a values than groups vaccinated with a gene alone (p<0.05). Lesion progression delayed for all immunized groups compared with control groups from 5th week post-infection (p<0.05). Mean lesion size decreased in immunized mice with fusion DNA than three groups vaccinated with one gene alone (p< 0.05). While, lesion size decreased significantly in cocktail recipient group than LeIF recipient group (p< 0.05). There was no difference in lesion size between fusion and cocktail groups. Overall, immunized mice with cocktail and fusion vaccines showed stronger Th1 response by production of higher IFN-gamma and IgG2a and showed smaller mean lesion size. Therefore, use of multiple antigens can improve induced immune responses by DNA vaccination

In vitro antileishmanial activity of hydroalcoholic Thymbra spicata extract on Leishmania major promastigotes

Cutaneous leishmaniosis is a major worldwide public health problem with annual incidence of 1.5 million cases across 98 countries. Treatment still relies on the use of chemical drugs with increasing resistance and side effects. The aim of this study was to investigate the anti-leishmanial effect of the hydroalcoholic Thymbra spicata extract on Leishmania major (L. major) promastigotes. In this study, 1x105 L. major promastigotes were cultured in 96-well plates and treated with different concentrations of hydroalcoholic T. spicata extract (12.5 to 400 mug/ml) then incubated at 25 degrees C for 24, 48 and 72 hours. Lethal percentage of promastigotes in each well was determined. RPMI 1640 medium containing L. major promastigotes with glucantime or without any treatment were used as positive and negative controls respectively. The 50 lethal concentration (LC50) of T. spicata extract and glucantime was calculated by GraphPad Prism software. The results indicated a significant decrease in the number of promastigotes treated with T. spicata extract and glucantime in comparison with negative control (P<0.0001). LC50 values for T. spicata extract were 18.49, 8.58, and 1.64 mug/ml after 24, 48 and 72 hours, respectively. In addition, anti-leishmanial effect of T. spicata extract and glucantime were dependent on concentration (P<0.0001). Our study revealed T. spicata extract as an herbal product against L. major promastigotes. However, more investigations are needed to find its antileishmanial activity in vivo and clinical trial studies

Global seroprevalence of Toxoplasma gondii in Camelidae: A systematic review and meta-analysis

PURPOSE: The present study aimed to analyze data available of the seroprevalence of Toxoplasma gondii (T. gondii) among camelids around the world. METHODS: The search was performed using seven international databases including Scopus, PubMed, Google Scholar, ProQuest, ScienceDirect, Web of Science, and EMBASE up to 11 October 2018. Random effects model was used to determine the pooled seroprevalence of T. gondii infection with 95 confidence intervals (CI) and analyzed data from four continents. Subgroup and meta-regression analyses were also performed according to continent and gender. RESULTS: In total, 42 studies out of 3517 published articles involving 14,542 camels from 17 countries were included for the final analyses. The global pooled seroprevalence of T. gondii infection in the Camelidae family was 28.16 (95 CI 23.64-32.68). Besides, the highest seroprevalence rate was in Europe (49.64) followed by Africa (37.63), America (21.76), and Asia (17.58). Moreover, the overall seroprevalence rates of T. gondii infection were 22 (95 CI 10-33) and 15 (95 CI 9-22) for the females and males, respectively. CONCLUSION: This meta-analysis showed a high seroprevalence of T. gondii infection in camelids as these animals play an important role in the transmission cycle of this zoonotic disease