The immune response and immunization studies in avirulent DK and virulent DS strains of Plasmodium chabaudi adami and a synthetic peptide immunization in P. chabaudi AS

In the first part of the present study the immune responses in NIH mice against asexual blood stages of either avirulent DK or virulent DS strains of P. chabaudi adami, in single or mixed infections, were examined using the ELISA test for the detection and measurement of cytokine and antibody production. The present results showed that the profile of the immune response in all the above infections suggests a sequential Thl/Th2 CD4+ T cell response. Previous studies have shown that there is a sequential Thl/Th2 response in Plasmodium chabaudi AS infection which is reflected in the activation of both cell- and antibody-mediated responses. These findings, therefore, indicate that vaccines which induce both arms of the protective immune response against malaria parasites could be most effective. The sequential Th1/Th2 response was supported by detecting early high levels of IFNγ and IgG2a during the acute phase of the infection and later by elevation of IL-4 and IgGl levels during the course of infection compared to controls. The levels of IgG2a were at highest levels at or immediately after the peak parasitaemia while the levels of IgG1 increased in later stages in the course of infection. However, a higher level IFNγ early in the infection indicated a stronger Thl response in the avirulent DK strain infection compared to the virulent DS strain or mixed infections. On the other hand, in the virulent DS infection a stronger Th2 response with higher IL-4 levels compared to the DK strain and mixed infections was observed in mice treated with chloroquine. In the mixed infection, an infective dose consisting of 8x103 pRBCs of the avirulent DK strain and 2x103 pRBCs of the virulent DS strain was used. Despite a relatively low number of pRBCs of the DS strain in the infective dose the peak parasitaemia was significantly higher than that in the single-infection of 1x104 pRBCs of the DK strain. The mixed infection also showed a significantly lower peak parasitaemia compared to that in mice given 1x104 pRBCs of the DS strain single-infection in untreated mice. So, it may be concluded that a higher peak parasitaemia in the mixed infection compared to the DK single-infection is reflected in a higher replication rate of the DS strain compared to the DK strain during the course of the mixed infection

Gentamicin-attenuated leishmania infantum vaccine: protection of dogs against canine visceral leishmaniosis in endemic area of southeast of Iran

An attenuated line of Leishmania infantum (L. infantum H-line) has been established by culturing promastigotes in vitro under gentamicin pressure. A vaccine trial was conducted using 103 naive dogs from a leishmaniosis non-endemic area (55 vaccinated and 48 unvaccinated) brought into an endemic area of southeast Iran. No local and/or general indications of disease were observed in the vaccinated dogs immediately after vaccination. The efficacy of the vaccine was evaluated after 24 months (4 sandfly transmission seasons) by serological, parasitological analyses and clinical examination. In western blot analysis of antibodies to L. infantum antigens, sera from 10 out of 31 (32.2%) unvaccinated dogs, but none of the sera from vaccinated dogs which were seropositive at >100, recognized the 21 kDa antigen of L. infantum wild-type (WT). Nine out of 31 (29%) unvaccinated dogs, but none of vaccinated dogs, were positive for the presence of Leishmania DNA. One out of 46 (2.2%) vaccinated dogs and 9 out of 31 (29%) unvaccinated dogs developed clinical signs of disease. These results suggest that gentamicin-attenuated L. infantum induced a significant and strong protective effect against canine visceral leishmaniosis in the endemic area

Correlation of Hematologic Indices with CT-pulmonary Arterial Obstruction Index in Patients with Acute Pulmonary Emboli

Introduction: Acute Pulmonary thromboembolism (PTE) is an imperative medical condition with a considerable global impact. Inflammation is deemed to take a notable part in the pathophysiology of this potentially fatal disorder. The aim of the current study was to predict acute PTE severity in helical pulmonary CT-angiography using easily accessible hematological complete blood count (CBC) indices.Methods: After exclusion of inflammatory conditions that may affect CBC parameters, a total of 69 consecutive patients with definite diagnosis of acute PTE according to pulmonary helical CT –angiography were recruited. Laboratory tests, including CBC parameters were performed on admission in the emergency unit, before initiation of any therapy. Neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR) and RDW to platelet ratio (RPR) were calculated in each case of acute PTE. Ultimately, CT pulmonary arterial obstruction index (PAOI) was assessed subsequent to pulmonary helical CT-angiography for each patient.Results: We found that NLR is positively correlated with acute PTE severity according to CT pulmonary arterial obstruction index (PAOI) (P < 0.01, r = 0.56); however, PLR, RDW and RPR did not appear to show such correlations (P > 0.05).Conclusions: NLR could be an easily calculated and capable index to predict severity of acute PTE in pulmonary CT-angiography. Consequently, NLR might be used in precise risk stratification when suspicious for acute PTE and in accurately triage of patients who would benefit greatly from urgent diagnostic and therapeutic interventions

Antimalarial effects of the hydroalcoholic extract of Allium paradoxum in vitro and in vivo

Malaria still is the most fatal parasitic disease affecting 50% of the world's population. Although annual deaths attributed to malaria has reduced, crucial importance of its prevention and treatment remains a priority for health care systems and researchers. The worldwide increase in resistance to most common antimalarial drugs such as chloroquine, their unpleasant side effects and low efficiencies persuade researchers to prioritize finding alternative drugs including herbal medication from plant roots. The present study aimed to examine in vitro and in vivo effects of hydroalcoholic extract of herbal medicinal plant, on growth rate in and The cytotoxicity assay was performed for hydroalcoholic extract of . The 3D7 strain of was cultured. The IC assay and enzymatic activity of lactate dehydrogenase were performed. BALB/c mice were infected with in vivo Toxicity and histopathological changes in the tissues of liver and kidney were also examined. The highest efficacy of extract was observed at 80 μg/mL in culture resulting in 60.43% growth inhibition compared to control groups. The significantly highest parasite growth inhibition with 88.71% was seen in the mice infected with when administered with 400 mg/kg extract compared to control groups. No significant changes in the liver and kidney cells were observed between experimental and control groups. The study showed that extract exhibited significant antimalarial properties in vitro on and in vivo in mice infected with There was no significant toxicity in the liver and kidney of the treated mice. [Abstract copyright: © Indian Society for Parasitology 2021.

Mean levels of specific anti-<i>Leishmania</i> total IgG antibody in the sera of vaccinated (♦) and unvaccinated dogs (▪).

<p>The dogs in the vaccinated group were injected with the <i>L. infantum</i> H-line and then transferred into the endemic area over a period of 1.5 months. Antibodies were detected by IFA pre-vaccination and over a 20 month period follow-up. The number of vaccinated dogs (n1) and unvaccinated dogs (n2) were assayed at each individual time point. After 1.5 months transferred into the endemic area. Each point represents average ± SDM.</p

Maps representing (a) the geographical locations where this study was carried out, in 3 villages of Baft County, Kerman Province, in the southeast of Iran.

<p>(b) Kerman city 225 Km of northwest of Dehsard, the leishmaniosis non-endemic area. Healthy German shepherd cross dogs obtained from Kerman city and brought into Dehsard, the leishmaniosis endemic areas.</p