Journal of Pathobiology Reaearch
Volume:22 Issue: 2, 2019

 Glucantime has been considered as a drug of choice for treating cutaneous leishmaniasis for many years. In the recent years, resistance to Glucantime has been increasingly reported in some regions of Iran. In the Leishmania, Arsenate/Antimony reductase acts on the basis of thiol metabolism; it can donate the electron from reduced glutaredoxin to pentavalent (sbV) antimony and arsenate and reduce them to trivalent (sbIII) antimony and arsenite, based on its enzymatic property. It has been assumed that a functional mutation in the enzyme can result in drug resistance. In the present study, the role of Sb (V)-As (V) reductase of Leishmania tropica in drug resistant to glucantime was investigated.

 In the present experimental research, 15 glucantime sensitive samples and 15 glucantime resistant specimens were collected from different regions of Iran through patients with cutaneous leishmaniasis. For mutation detection, first degenerate primers were designed; then, sequencing and simulation techniques were used based on molecular dynamics method.

In Leishmania tropica-resistant isolates, only one mutation was seen as replacing alanine (Ala) at position 80 instead of valine (Val). The analysis of the radius of gyration did not reveal any increase in the radius of gyration while simulation.

Mutations in glucantime-resistant isolates did not significantly change simulated active site of antimony ion.

 Enterotoxigenic Escherichia coli (ETEC) is the most important bacteria causing traveler’s diarrhea. The bacterium has several virulence factors, including colonization factors (CFs) or Escherichia coli adhesins, heat-labile (LT), and heat-stable (ST) toxins. The design and production of vaccine against this disease is one of the goals of the World Health Organization due to increased antibiotic resistance and a reduction of healthy water sources. An effective subunit vaccine against ETEC could include a toxoid from both toxins and colonization factors. The aim of the current study was to express, purify, and encapsulate the recombinant protein in chitosan nanoparticles.

 In the present experimental study, the E. coli BL21DE3 harbring pET- 28a-cscl vector was used. The chimeric cscl gene is composed of cfab along with st toxin, cfae, and ltb. After the expression and purification of recombinant protein, using Ni-NTA column, Western blotting was performed with anti-His antibody. Then, the CSCl protein was encapsulated in chitosan nanoparticles and the particle size was measured.

 The recombinant CSCL protein was purified by Ni-NTA column and urea denaturation method. Then, this purified protein (~57kDa) was confirmed by Western blotting and the size of the nanoparticles was estimated as 112.0 nm with 98.8% of encapsulation efficiency.

 With some advantages, including the presence of surface and important antigens of ETEC and encapsulating in chitosan nanoparticles, the CSCL recombinant protein can be considered as a candidate for producing oral nanovaccine and stimulating of mucosal and systemic immune response.

 The chimeric domain-exchanged streptokinase (SKch) between two sk genes from groups G and A streptococci (SK2aG88 and SK2bALAB49, respectively) was constructed to evaluate the role of SK-domains (α, β, γ) in α2-antipalsmin-resistance variations of SK.

 In this experimental study, PCR-amplified genes of streptococci (skg, ska) were cloned into pET26b vector to produce pET26-SKG88 and pET26-SKALAB49. For domain exchange, the amplicon containing β and γ domains of SK2bALAB49 was replaced for that of the SK2aG88 within pET-SK2aG88 (pET26-SKch; α2aG88β2bALABγ2bALAB). All constructs were confirmed by restriction analyses/agarose-gel electrophoresis and DNA sequencing, transformed into E.coli Rosetta, and induced by IPTG for protein expression. Proteins were purified by Ni-NTA chromatography, quantified by Bradford method, and analyzed by SDS-PAGE/Western blotting assays. The α2-antipalsmin-resistance was measured by S2251 colorimetric assay for plasminogen activation.

 SDS-PAGE and western blotting results indicated the expression of proteins with the size of 47kD. At the highest concentration of α2-antiplasmin, SK2aG88 remained 80% active, whereas the SK2bALAB49 and SKch retained 55% of their activity.

 SKch shows similar activity reduction, indicating the minor role of the α domain compared to β and γ domains for α2-antipalsmin-resistance.

 The aim of this study was investigation of contamination rate and determination of pattern of antibiotic resistance in coagulase positive Staphylococcus aureus isolated from domestic cheeses in Maragheh, Iran.

In this experimental study, 100 traditional white brine cheese samples were collected from different villages of Maragheh with the observance of aseptic principles and transferred to microbiology laboratory of Islamic Azad University, Maragheh branch. The samples were cultured in specific media and the complementary biochemical tests were done for the identification of coagulase positive Staphylococcus aureus. For molecular diagnosis of S.aureus, these isolates were identified as S.aureus with the proliferation of Thermonuclease species-specific gene (nuc) by polymerase chain reaction (PCR) method. Cheese samples were tested for pH and NaCl content. The susceptibility of all isolates to different antibiotics was evaluated by kirby-bauer’s method.

Of 100 samples taken from villages of Maragheh, 21 samples (21%) were identified as Staphylococcus aureus coagulase positive. 20 isolates were resistant to more than one antibiotic. The most resistance of isolates were to penicillin, vancomycin, and methicillin, respectively. No significant difference was shown among old and fresh samples in Staphylococcus aureus incidence (p>0.05).

Considering the high contamination rate of domestic cheese by coagulase positive Staphylococcus aureus in Maragheh, the production and distribution of these cheeses should be under hygienic situations. Efficient informing about the potential risk of using these products seems necessary.

 Visceral leishmaniasis (VL) is one of the most important endemic diseases in Meshkinshahr. The present study was aimed to molecular detect of VL and babesiosis in clot blood samples taken from dogs.

 In this experimental study, a total number of 148 blood samples were collected from dogs with clinical signs of visceral leishmaniasis from Meshkinshahr area. All serum samples were examined by direct agglutination test (DAT). DNA was extracted from the blood clot with the DNG-plus Extraction Kit. The ITS1 and kDNA genes of L. infantum were amplified by the PCR method. To identify and confirm the existence of Babesia parasites, 2 pairs of Babesia-specific primers were used.

 All of 148 dogs (100%) showed titers more than 1:320 of L. infantum infection in the serological test. L. infantum kDNA was detected by PCR in all samples. No cases of infection with Babesia parasite found in the samples.

 The dog owners in Meshkinshehr are in close contact with dogs which are positive for VL, so, the implementation of health care in this region is highly recommended.

 Despite recent advances in diagnosis and treatment, breast cancer still remains the second leading cause of cancer- related death in women. Recent reports have detected a new class of non-coding molecules named long non-coding RNAs that play an important role in various biological processes involved in cancer. This study aimed to evaluate the expression level of long non-coding RNA HULC in breast cancer.

 In this experimental study, after collecting 40 breast tumors with invasive ductal carcinoma and 40 normal marginal tissues, RNA extraction and cDNA synthesis were done. The expression level of HULC was obtained by using the qRT-PCR method. REST 2009 software was employed to evaluate the association of its expression in tumor and normal tissues. Biomarker potential of HULC was evaluated by drawing ROC curve. Relationship between HULC expression and clinicopathological features was analyzed.

 Results from REST indicated significant upregulation of HULC in tumor tissues compared to normal marginal specimens (95% CI; p=0.0001). ROC curve analysis also demonstrated the biomarker potential of HULC in breast cancer (ROCAUC=0.79; p<0.0001). Evaluation of the relationship between HULC expression and clinicopathological features revealed that there is a statistically significant positive correlation of HULC expression with advanced stages (95% CI; P=0.019).

 Considering the upregulation of HULC expression in invasive ductal carcinoma, this lncRNA could be considered as a new potential diagnostic biomarker in breast cancer.

Functional disorder in different tissues is a consequence of cell damage in a part of a tissue that can occur because of diseases, traumas, or accidents. Organ transplantation has so far been the only treatment approach for these damages; however, transplantation therapies have been greatly limited by the serious shortage of donors or immune rejection. One of the alternative approaches is tissue engineering that recently has attracted the tremendous attentions of many researchers. Cell sheet engineering is a technology that can construct bioengineered sheet-like tissues without the need of using scaffolds and it is called “scaffold-free tissue engineering”. Cells are cultured at 370C on the surfaces grafted with the temperature responsive polymer “poly (N-isopropylacrylamide)”. Then, the cell sheet is harvested with a simple reducedtemperature treatment up to 200C and transplanted directly onto the injured surface without sutures or glues. In the present article, researches and experiments in the field of cell sheet engineering have been paid attention. Moreover, the advantages and challenges of this method have been discussed.