Analysis of NSP4 gene and its association with genotyping of rotavirus group a in stool samples

Background: Non-structural protein 4 [NSP4] is a critical protein for rotavirus [RV] replication and assembly. This protein has multiple domains and motifs that predispose its function and activity. NSP4 has a sequence divergence in human and animal RVs. Recently, 14 genotypes [E1-E14] of NSP4 have been identified, and E1 and E2 have been shown to be the most common genotypes in human

Methods: The gene and protein sequence of NSP4 in RV-positive samples were inspected with the aim of NSP4 genotyping and variation analysis in viroporin and other domains. P and G typings of RV samples were carried out by WHO primers using a semi-multiplex PCR method. Non-typeable RV samples were amplified by conserved primers and sequenced

Results: In viroporin and enterotoxin, conserved sequence was detected, and amino acids substitution with the same biochemical properties was found

Conclusion: Association of NSP4 genotype with P or G genotyping G1/G9 correlates with E1 genogroups. In electrophoretyping of RV, E2 genotype had a short pattern when compared to E1

Distribution of rotavirus genotypes circulating in Ahvaz, Iran in 2016

Background: Group A rotavirus [RVA] mainly causes acute gastroenteritis, exclusively in young children in developing countries. The prevalence and determination of the molecular epidemiology of rotavirus genotypes will determine the dominant rotavirus genotypes in the region and will provide a strategy for the development of appropriate vaccines

Methods: A total of 100 fecal samples were collected from children below five years with acute gastroenteritis who referred to Aboozar Children's Hospital of Ahvaz city during October 2015 to March 2016. All samples were screened by latex agglutination for the presence of rotavirus antigen. Rotavirus-positive samples were further analyzed by the semi-multiplex RT-PCR, and the sequencing was performed for G/P genotyping

Results: Findings showed that 32% of the specimens were RVA-positive. Among the 32 VP7 genotyped strains, the predominant G genotype was G9 [37.5%], followed by G2 [21.9%], G1 [12.5%], G12 [9.4%], G4 [9.4%], G2G9 [6.3%], and G3 [3.1%]. Among the 31 VP4 genotyped strains, P[8] genotype was the dominant [62.5%], followed by P[4] [31.3%] and P[4] P[8] [3.1%]. The genotypes for G and P were identified for 31 rotaviruses [96.87%], but only one strain, G9, remained non-typeable for the P genotype. The most prevalent G/P combination was G9P[8] [28.5%], followed by G2P[4] [18.8%], G1P[8] [9.4%], G12P[8] [9.4%], G4P[8] [9.4%], G2G9P[4] [6.3%], G9P[4] P[8] [3.1%], G3P[8] [3.1%], G9P[4] [3.1%], G2P[8] [3.1%], and G9P[nontypeable] [3.1%]

Conclusion: A novel rotavirus strain, G12, was detected, for the first time, in patients from the southwest of Iran. Comprehensive investigations are required to evaluate the emergence of this strain

Epidemiology of rotavirus-norovirus co-infection and determination of norovirus genogrouping among children with acute gastroenteritis in Tehran, Iran

Background: Enteric viruses, particularly human rotavirus and norovirus, have been shown to replace bacteria and parasites, as the most common pathogens responsible for acute diarrhea. However, there are still few epidemiological data on the simultaneous occurrence of these viruses in Iran. In this regard, the aim of this study was to assess the useful epidemiological data on the gastroenteritis associated with rotavirus-norovirus mixed infection and to examine the prevalence of norovirus genogrouping among children aged less than five years old in Iran

Methods: A total of 170 stool samples were collected from children under five years of age with the clinical signs and symptoms of acute gastroenteritis, from May 2013 to May 2014. For the detection of both rotavirus and norovirus, total RNA was extracted from all samples, followed by reverse transcription polymerase chain reaction [RT-PCR]. For both detected rotaviruses and noroviruses, genogrouping was performed

Results: Of 170 samples, 49 [28.8%] and 15 [8.8%] samples were found to be positive for rotavirus and norovirus infections by RT-PCR. Interestingly, 6 [3.5%] patients were positive for both infections. Among the 15 norovirus-positive patients, 13 [86.6%] and 2 [13.3%] belonged to genogroups GII and GI

Conclusions: The norovirus genogroup GII and rotavirus lead to the serious infections in children with acute gastroenteritis. However, more well-designed studies are needed to further elucidate the role of other enteric viruses in acute gastroenteritis

case-control study on occult hepatitis b infection in chronic hemodialysis patients from south-west of Iran

Blood born viral infections such as hepatitis B virus [HBV] are major concerns in chronic hemodialysis [CHD] patients and hemodialysis units. Undetected HB[s] Ag in the presence of viral DNA, occult HBV infection [OBI], isa concern in the care of CHD patients and hemodialysis unit as a mode of transmission.In this case-control study we compare the frequency of OBI in the CHD patients with the normal population.82 consecutive CHD patients and 82 healthy individuals without any risk factors for HBV infection were enrolled in this study. A selection criterion was negative serum HB[s] Ag by ELISA method. Subsequently, the sera were tested for HBV DNA by nested PCR method.In the CHD group, 55 [67.1%] were male and 27 [32.9%] were female, with the overall mean age of 54.32 +/- 13.67 years old. The mean age of control group was 32.65 +/- 8.51 years old, with 26 [31.7%] male and 56 female [69.3%]. HBV DNA was present in 9 [11%] CHD patients, 4 [8%] of whom were seronegative for anti-HBc and anti-HB[s] antibodies. No HBV DNA was identified in the control group [p<0.0001]. History of blood transfusion was presentin all OBI CHD patients and 59 [80.9%] of non-OBI CHD patients. Duration of hemodialysis in OBI CHD and non-OBI CHD patients were 73.56 +/- 39.53 and 44.24 +/- 24.59 months, respectively [p =0.002]. The prevalence of occult HBV infection is relatively high in patients with chronic hemodialysis in our region. Duration of hemodialysis and history of blood transfusion are important risk factor for OBI infection. A more sensitive method, such as PCR, may need to be considered in this patient population

The influence of substrate topography and biomaterial substance on skin wound healing / 대한해부학회지

Tissue engineering is a new field of which the main purpose is to regenerate and repair the damaged tissues. Scaffolds serve as three dimensional matrices for neo-organogenesis and their substance can be biologic or synthetic. Natural polymers have good interactions with the cells and synthetic biomaterials are also highly useful in biomedical application because of their biocompatible properties. In addition to scaffold substance, surface properties of biomaterials have an important role in tissue engineering. In this study, we examined whether substrate substance is important for wound healing or its surface topography. Therefore, we fabricated two matrices, electrospun polycaprolactone (PCL) nanofibers and collagen/chitosan film, and implanted them to the same rat models. After 2 weeks, the sizes of healing wounds were measured and their cellular structures were evaluated by histochemistry and mmunohistochemistry. Histological staining showed a good level of cellularization and epidermis-dermis formation in PCL implant while no determinable epithelium was observed after 2 weeks in collagen-chitosan graft. Immunohistochemical study demonstrated the highly expressed pancytokeratin in PCL graft while its expression was weak in underdeveloped epidermis of collagen-chitosan implantation. In conclusion, this study suggested that PCL nanofibers with high surface area had a more ideal property than natural collagen-chitosan film, therefore the structure and topography of a matrix seemed to be more important in wound healing than its material substance.

Development of Enzyme-Linked Immunosorbent Assays Using 2 Truncated ORF2 Proteins for Detection of IgG Antibodies Against Hepatitis E Virus

BACKGROUND: Without appropriate culture systems for hepatitis E virus (HEV), sufficient natural viral proteins are difficult to generate for use in serological tests. Therefore, it is important to produce large amounts of HEV recombinant proteins in an economical way. The present study developed ELISAs using 2 truncated forms of the HEV open reading frame (ORF) 2 protein in order to detect anti-HEV IgG in serum samples. METHODS: Two truncated forms of the ORF2 protein were expressed in Escherichia coli and were purified by Ni2+-chelate-affinity chromatography (Qiagen, Germany). Two ELISAs were developed using these proteins and were compared with DIA.PRO HEV IgG ELISA kit (DIA.PRO. Italy) in 220 serum samples. RESULTS: High yields of the target proteins were obtained through codon optimization. The concentration and purity of the proteins were improved with Amicon filters (EMD Millipore, USA). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting analysis of the resultant proteins showed a protein band of approximately 60 kDa corresponding to ORF2.1 (amino acids 112-660) and a protein band of approximately 55 kDa corresponding to ORF2.2 (amino acids 112-607). Positive agreement, negative agreement, and concordance of the 2 in-house ELISAs compared with DIA.PRO HEV IgG ELISA kit were 87%, 99.5%, and 98.1%, respectively (kappa=0.899, P=0.625). CONCLUSIONS: The newly developed ELISAs are useful for detecting anti-HEV IgG in serum samples and are highly concordant with DIA.PRO HEV IgG ELISA kit.