Antileishmanial and Cytotoxic Effects of Essential Oil and Methanolic Extract of Myrtus communis L.

Plants used for traditional medicine contain a wide range of substances that can be used to treat various diseases such as infectious diseases. The present study was designed to evaluate the antileishmanial effects of the essential oil and methanolic extract of Myrtus communis against Leishmania tropica on an in vitro model. Antileishmanial effects of essential oil and methanolic extract of M. communis on promastigote forms and their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 hr. In addition, their leishmanicidal activity against amastigote forms was determined in a macrophage model, for 72 hr. Findings showed that the main components of essential oil were α-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%). Findings demonstrated that M. communis, particularly its essential oil, significantly (P<0.05) inhibited the growth rate of promastigote and amastigote forms of L. tropica based on a dose-dependent response. The IC₅₀ values for essential oil and methanolic extract was 8.4 and 28.9 μg/ml against promastigotes, respectively. These values were 11.6 and 40.8 μg/ml against amastigote forms, respectively. Glucantime as control drug also revealed IC₅₀ values of 88.3 and 44.6 μg/ml for promastigotes and amastigotes of L. tropica, respectively. The in vitro assay demonstrated no significant cytotoxicity in J774 cells. However, essential oil indicated a more cytotoxic effect as compared with the methanolic extract of M. communis. The findings of the present study demonstrated that M. communis might be a natural source for production of a new leishmanicidal agent.     

Sympatric morphotypes of the restricted-range Tashan Cave Garra: distinct species or a case of phenotypic plasticity?

Environmental Biology of Fishes - Among Tashan cave barb Garra tashanensis inhabiting a small cave in southwest Iran, two mental disc (sucking mouth disc) forms were observed. To assess their...     

Thermal stability and enzymatic activity of RNase A in the presence of cationic gemini surfactants

The thermal stability and enzymatic activity of bovine pancreatic ribonuclease A (RNase A) have been investigated in the presence of a homologous series of cationic gemini surfactants (alkanediyl-α,ω-bis(hydroxyethyl methyl hexadecyl ammonium bromide)). UV, circular dichorism and fluorescence spectroscopies have been used for this study. The denaturation curves at various surfactant concentrations were analyzed on basis of a two-transition model to obtain values of T(m) (temperature at the midpoint of denaturation) and ΔH(m) (enthalpy change at T(m)) of each transition. The main conclusion of this study is that these cationic gemini surfactants slightly activate and stabilize RNase A below their critical micelle concentrations at pH 5.0. The cationic gemini surfactant with the shorter spacer interacts more efficiently with RNase A than those with longer spacers.     

Retraction: Effect of controlled and uncontrolled cooling rate on motility parameters of cryopreserved ram spermatozoa

ABSTRACT: Retraction This article [1] has been retracted at the request of the Editor. Although the authors withdrew their submission in order to publish elsewhere, the article was subsequently transmitted to the journal's production department which resulted in it being published in error.     

First survey of the two polymorphisms (Arg194Trp and Arg399Gln) in XRCC1 gene in four Afghanistan populations and comparison with worldwide data

Genetic polymorphisms in gene encoding X-ray repair cross-complementation group 1 (MIM: 194360; XRCC1) have been defined. Previous studies have revealed that there was significant difference between populations for allelic frequency of Arg194Trp (rs. 1799782) and Arg399Gln (rs. 25487) polymorphisms of XRCC1. In order to get more insight into the genetic structure of Afghanistan populations the present study was carried out. Present study was done on 656 (257 Pashtuns, 217 Tajiks, 120 Hazaras, and 62 Uzbeks) unrelated healthy Afghanis refuges living in Fars province (southern Iran). Genotypes for Arg194Trp and Arg399Gln polymorphisms of the XRCC1 were detected by RFLP-PCR method. The prevalence of the 194Trp allele in Pashtuns, Tajiks, Hazaras, and Uzbeks was 0.072, 0.085, 0.108, and 0.145, respectively. The frequency of the 399Gln in Pashtuns, Tajiks, Hazaras, and Uzbeks was 0.362, 0.378, 0.296, and 0.234, respectively. There was significant difference between these ethnic groups for the genotypic distributions of the Arg194Trp (χ² = 16.70, df = 6, P = 0.010) and Arg399Gln (χ² = 12.67, df = 6, P = 0.049) polymorphisms. Based on the complete dataset, these polymorphisms showed significant linkage disequilibrium. There was significant difference between the ethnic groups for prevalence of the haplotypes (χ² = 16.67, df = 6, P = 0.011). Uzbeks showed significant difference with the other ethnic groups (χ² = 10.09, df = 2, P = 0.006). The allelic frequencies of 194Trp and 399Gln in Pashtuns and Tajiks seem to be more similar to the Caucasians than the Asian populations. However, Uzbeks seems to be intermediate between Afghanis’ Caucasian (Pashtuns and Tajiks) and Asians.     

Enhancing compost quality by using whey-grown biosurfactant-producing bacteria as inocula

Wild screening of bacterial strains from compost materials was performed. Several biosurfactant-producer strains were isolated and then cultured in whey as a low-cost medium for biosurfactant production. Two strains, identified as Bacillus sp. and Streptomyces sp., were the best biosurfactant producers and were selected for determination of compost quality enhancing. The effect of cell biomass, cell-free supernatant, and a consortium of these two strains on compost quality were determined and specific parameters of compost were analyzed. The results showed that using these bacteria (or supernatants) in compost processing have slight stimulatory effect on bacterial population (8.08 log₁₀ CFU/g), surface tension reduction (to 42.6 mN/m at 24 h), and heavy metal bioremediation (>50 % in most treatments), speeding up the decomposition rate of organic matter (42.3 % OM at the end of experiment), accelerating the stabilization process by reduction of NH ₄ ⁺ to NO ₃ ^? ratio (reduced from 0.2 to 0.026), decreasing the biotoxicity (tested by seed germination and root length of germinated seed), and also reduction of pathogens (reduced from 2100 to 120 MPN/g in fecal coliform).     

Age-related macular degeneration and genetic polymorphisms of glutathione <Emphasis Type="Italic">S</Emphasis>-transferases M1 (<Emphasis Type="Italic">GSTM1</Emphasis>) and T1 (<Emphasis Type="Italic">GSTT1</Emphasis>)

The aim of this study is to understand the multifactorial causes of age-related macular degeneration (ARMD), and, therefore, it is reasonable to investigate whether genetic polymorphisms of antioxidant enzymes (GSTM1 and GSTT1) contribute to the development of ARMD. This study consisted of 112 subjects (44 females, 68 males) with exudative ARMD, who were recruited from Khalili Hospital ophthalmic clinic in Shiraz (southern Iran), referred by vitreoretinal surgeon. Also 112 sex-matched controls (44 females, 68 males) were randomly selected from unrelated volunteers in the same clinic. We excluded patients and controls with cataract or past history of cataract surgery, asthma, past history of malignancy, cardiovascular disease that on medication and known cases of glaucoma, because these traits were associated with GSTM1 and/or GSTT1 polymorphisms. There was no association between polymorphisms of neither GSTM1 nor GSTT1 and risk of ARMD. The combination genotypes of GSTM1 and GSTT1 were not associated with the risk of ARMD. We considered the time of deterioration of vision as the time of onset of exudative ARMD. The Kaplan–Meier analysis revealed that there was significant difference between genotypes of GSTM1 (log rank statistic = 7.03, df = 1, P = 0.008). The age at onset among GSTM1 null genotype was lower than the active genotype of GSTM1. Our results support the hypothesis that the protein encoded by the GSTM1 gene might have a protective function against oxidative stress in retina. Since the age at onset is influenced by the GSTM1 polymorphism, this implies that GSTM1 is a modifier gene.     

EPIYA motif is a membrane-targeting signal of Helicobacter pylori virulence factor CagA in mammalian cells

Helicobacter pylori contributes to the development of peptic ulcers and atrophic gastritis. Furthermore, H. pylori strains carrying the cagA gene are more virulent than cagA-negative strains and are associated with the development of gastric adenocarcinoma. The cagA gene product, CagA, is translocated into gastric epithelial cells and localizes to the inner surface of the plasma membrane, in which it undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motif. Tyrosine-phosphorylated CagA specifically binds to and activates Src homology 2-containing protein-tyrosine phosphatase-2 (SHP-2) at the membrane, thereby inducing an elongated cell shape termed the hummingbird phenotype. Accordingly, membrane tethering of CagA is an essential prerequisite for the pathogenic activity of CagA. We show here that membrane association of CagA requires the EPIYA-containing region but is independent of EPIYA tyrosine phosphorylation. We further show that specific deletion of the EPIYA motif abolishes the ability of CagA to associate with the membrane. Conversely, reintroduction of an EPIYA sequence into a CagA mutant that lacks the EPIYA-containing region restores membrane association of CagA. Thus, the presence of a single EPIYA motif is necessary for the membrane localization of CagA. Our results indicate that the EPIYA motif has a dual function in membrane association and tyrosine phosphorylation, both of which are critically involved in the activity of CagA to deregulate intracellular signaling, and suggest that the EPIYA motif is a crucial therapeutic target of cagA-positive H. pylori infection.     

Fifty years of struggle to control cutaneous leishmaniasis in the highest endemic county in Iran: A longitudinal observation inferred with interrupted time series model

Negligible data are available following major social activities and environmental changes on leishmaniasis. Therefore, how interactions between these events influence cutaneous leishmaniasis (CL) risk is not well-known. This longitudinal study was undertaken to explore the impact of interventions conducted between 1971 and 2020 in Bam county, which has had the highest disease burden in Iran. Only confirmed CL cases during this period were taken into account. Data were analyzed by SPSS 22 using the X² test to assess the significance of the difference between proportions. Moreover, we used interrupted time series (ITS) to assess the impact of three environmental events during this period. Overall, 40,164 cases of CL occurred in the past five decades. Multiple complex factors were among the leading causes that synergistically induced the emergence/re-emergence of CL outbreaks in Bam. The main factors attributed negatively to CL control were cessation of malaria spraying activity, expansion of the city spaces, and a massive earthquake creating new breeding potentials for the vectors. The highest impact on CL incidence during these years was related to the earthquake [coefficient = 17.8 (95% CI: 11.3, 22.7); p-value < 0.001]. Many factors can contribute to CL outbreaks in endemic foci. They also can cause new foci in new areas. Since humans are the single reservoir for CL in this area, early detection and effective management significantly contribute to controlling CL to reduce the disease burden. However, essential evidence gaps remain, and new tools are crucial before the disease can ultimately be controlled. Nevertheless, sustained funding and more trained task forces are essential to strengthen surveillance and case management and monitor the interventions’ impact.