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Trachoma is a blinding disease caused by repeated conjunctival infection with different Chlamydia trachomatis (Ct) genovars. Ct B genovars have been associated with more severe trachoma symptoms. Here, we investigated associations between Ct genovars and bacterial loads in ocular samples from two distinct geographical locations in Africa, which are currently unclear. We tested ocular swabs from 77 Moroccan children (28 with trachomatous inflammation-follicular (TF) and 49 healthy controls), and 96 Sudanese children (54 with TF and 42 healthy controls) with a Ct-specific real-time polymerase chain reaction (PCR) assay. To estimate bacterial loads, Ct-positive samples were further processed by multiplex real-time qPCR to amplify the chromosomal outer membrane complex B and plasmid open reading frame 2 of Ct. Genotyping was performed by PCR-based amplification of the outer membrane protein A gene (~1120 base pairs) of Ct and Sanger sequencing. Ct-positivities among the Moroccan and Sudanese patient groups were 60·7% and 31·5%, respectively. Significantly more Sudanese patients than Moroccan patients were genovar A-positive. In contrast, B genovars were significantly more prevalent in Moroccan patients than in Sudanese patients. Significantly higher Ct loads were found in samples positive for B genovars (598596) than A genovar (51005). Geographical differences contributed to the distributions of different ocular Ct genovars. B genovars may induce a higher bacterial load than A genovars in trachoma patients. Our findings emphasize the importance of conducting broader studies to elucidate if the noted difference in multiplication abilities are genovar and/or endemicity level dependent., Author summary We investigated the association between different Ct genovars, the approximate load of infection, and the distribution of Chlamydia genovars by comparing samples from one trachoma-endemic area (i.e., the city of El-Gadaref in Al Qadarif, Sudan) and one previously endemic area (i.e., the Zagora Province in Morocco), currently considered as non-endemic. This study is the first to reveal a significant difference between the genome copy numbers of Ct genovar A and B/Ba in children with TF. Evidence that Ct is still circulating in rural foci of countries like Morocco that are no longer considered endemic implies that the continuation of the trachoma surveillance must be warranted in future to avoid further spreading of Ct. The clinical significance of different infectious loads in the development of sequelae has to be determined as well as whether these differences are genovar specific or related to the given endemicity level.

Aim of the study Chitosan, a partially deacetylated polysaccharide derived from chitin, and chitosan-N-acetylcysteine (C-NAC), a thiolated chitosan, both show enhanced retention times on the ocular surface when compared to other polymers commonly used in eye drops. To evaluate these compounds as adjuvants for ocular drug delivery or uptake of topically administered conjunctival vaccines, biochemical characteristics of both polymers were investigated in vitro and in vivo. # Methods Human conjunctival epithelial (HCjE) cells were used to investigate biocompatibility of buffered chitosan and C-NAC containing formulations. Cellular uptake was studied using fluorescein-isothiocyanate (FITC)-labelled polymers. Transepithelial electrical resistance (TEER) measurements were performed to determine effects of chitosan on tight junctions of stratified HCjE cells in vitro. In vivo uptake of topically applied chitosan into conjunctival epithelial cells was investigated in guinea pigs. # Results Minimal effects on cell viability were seen with both compounds after application for 30 min in a concentration of 0.1%. In vitro uptake into HCjE cells was only observed with the chitosan containing solution. An effect on tight junctions was demonstrated by significantly (P

Ocular chlamydial infections with the ocular serovars A, B, Ba, and C of Chlamydia trachomatis represent the world’s leading cause of infectious blindness. Carrageenans are naturally occurring, sulfated polysaccharides generally considered safe for food and topical applications. Carrageenans can inhibit infection caused by a variety of viruses and bacteria. To investigate whether iota-carrageenan (I-C) isolated from the red alga Chondrus crispus could prevent ocular chlamydial infection, we assessed if targeted treatment of the conjunctival mucosa with I-C affects chlamydial attachment, entry, and replication in the host cell. Immortalized human conjunctival epithelial cells were treated with I-C prior to C. trachomatis infection and analyzed by flow cytometry and immunofluorescence microscopy. In vivo effects were evaluated in an ocular guinea pig inclusion conjunctivitis model. Ocular pathology was graded daily, and chlamydial clearance was investigated. Our study showed that I-C reduces the infectivity of C. trachomatis in vitro. In vivo results showed a slight reduced ocular pathology and significantly less shedding of infectious elementary bodies by infected animals. Our results indicate that I-C could be a promising agent to reduce the transmission of ocular chlamydial infection and opens perspectives to develop prophylactic approaches to block C. trachomatis entry into the host cell.

Supplemental Digital Content is Available in the Text., Purpose: To investigate toxicity associated with buffers commonly used in topical ocular drug formulations using a human corneal–limbal epithelial (HCLE) and a human conjunctival epithelial (HCjE) cell model. Methods: HCLE and HCjE cells were incubated for 10, 30, or 60 minutes with 4 different buffers based on borate, citrate, phosphate, and Tris-HCl at 10, 50, and 100 mM concentrations. To detect possible delayed effects on cell viability, after 60 minutes of buffer incubation, cells were further incubated for 24 hours with a cell medium. Cell viability was determined using a colorimetric XTT–based assay. The morphology of cells was also investigated. Results: HCjE cells showed more sensitivity to buffer incubation than HCLE cells. The 100 mM phosphate buffer displayed significant delayed effects on cell viability of HCLE 16.8 ± 4.8% and HCjE 39.2 ± 6.1% cells after 60 minutes of exposure (P < 0.05). HCjE cell viability was reduced after 60 minutes incubations with 50 and 100 mM citrate buffer to 42.8 ± 6.5% and 39.3 ± 7.9%, respectively, and even lower percentages at the delayed time point (both P < 0.05). HCLE cell morphology was distinctly altered by 100 mM phosphate and Tris buffers after 30 minutes, whereas HCjE cells already showed marked changes after 10 minutes of exposure to 100 mM citrate and phosphate buffers. Conclusions: We observed a time-dependent decrease of viability in both HCLE and HCjE cells exposed to higher buffer concentrations. Therefore, we propose further in vivo studies to translate these finding to humans to discern the real effects of the buffer concentration in eye drops on the ocular surface.

The aim of this study was to determine whether infectious dose of Chlamydia caviae after repeated infections influences the immunological responses and subsequent clearance of pathogen at the ocular surface of guinea pigs. Animals were infected three times via the conjunctiva at six- and twelve-week intervals by applying either 1 x 10(4) or 1 x 10(6) inclusion-forming units (IFUs) of C. caviae. Ocular pathology, infection course, C. caviae-specific serum IgG levels and their capacity to bind and neutralize infection ex vivo were assessed. Animals infected with 1 x 10(4) IFUs had completely diminished ocular infection and pathology after the 2nd infection with increased levels of C. caviae-specific serum IgG and their effective capacity to bind and neutralize C. caviae. Only partial protection was observed in animals infected with 1 x 10(6) IFUs after the 2nd and 3rd infections. Our findings show that full protection was observed in animals repeatedly infected with the lower dose. The lower dose appeared not to compromise the host immune system, thereby enabling fast clearance of the pathogen and the establishment of competent neutralizing antibodies. (C) 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Following infection, the balance between protective immunity and immunopathology often depends on the initial infectious load. Several studies have investigated the effect of infectious dose; however, the mechanism by which infectious dose affects disease outcomes and the development of a protective immune response is not known. The aim of this study was to investigate how the infectious dose modulates the local and systemic humoral and the cellular immune responses during primary ocular chlamydial infection in the guinea pig animal model. Guinea pigs were infected by ocular instillation of a Chlamydophila caviae-containing eye solution in the conjunctival sac in three different doses: 1x10(2), 1x10(4), and 1x10(6) inclusion forming units (IFUs). Ocular pathology, chlamydial clearance, local and systemic C. caviae-specific humoral and cellular immune responses were assessed. All inocula of C. caviae significantly enhanced the local production of C. caviae-specific IgA in tears, but only guinea pigs infected with the higher doses showed significant changes in C. caviae-specific IgA levels in vaginal washes and serum. On complete resolution of infection, the low dose of C. caviae did not alter the ratio of CD4(+) and CD8(+) cells within guinea pigs' submandibular lymph node (SMLN) lymphocytes while the higher doses increased the percentages of CD4(+) and CD8(+) cells within the SMLN lymphocytes. A significant negative correlation between pathology intensity and the percentage of CD4(+) and CD8(+) cells within SMLN lymphocyte pool at selected time points post-infection was recorded for both 1x10(4), and 1x10(6) IFU infected guinea pigs. The relevance of the observed dose-dependent differences on the immune response should be further investigated in repeated ocular chlamydial infections.

Chlamydia trachomatis (Ct) can induce scarring disease of the ocular mucosa, known as trachoma, the most common infectious cause of blindness worldwide. We hypothesized that epithelial-mesenchymal transition (EMT) contributes to the fibrotic process in trachomatous scarring. Infection of human conjunctival epithelial cells (HCjE) with Ct activated signaling pathways involved in EMT induction, which was correlated with decreased expression of E-cadherin, guardian of the epithelial phenotype. In addition, Ct infection was associated with increased expression of two mesenchymal cell markers: fibronectin and α-SMA. The DNA methylation statuses of selected regions of E-cadherin, fibronectin, and α-SMA genes revealed that Ct infection was accompanied with changes in DNA methylation of the E-cadherin promoter, while the expression of the two mesenchymal markers was not related with this epigenetic event. Our data suggest that Ct infection of conjunctival epithelial cells induces EMT-like changes that go along with modification of the methylation profile of the E-cadherin promoter and could, as one of the earliest events, contribute to processes triggering conjunctival scarring. Frontiers in Cellular and Infection Microbiology (2017), 7(JUN): 253

The advantages of solid state fermentation (SSF) utilization in producing enzymes & secondary metabolites have been shown, whereas, submerged liquid fermentation (SLF) condition has the major usage in industrial production of antibiotics. As an antibiotic of B-lactams group, cephalosporin-C (CPC) is indicated due to its wide effect and broad convention in treatment of infectious diseases. Regarding industrial production of CPC regularly done in SLF condition, we compared CPC production sum in SLF and SSF conditions. In this analysis, A. chrysogenum was employed, which was inoculated to SLF and SSF, while internal fermenter conditions were totally under control. After extraction of CPC, productions in two states of SLF and SSF were compared using the cylinder plate method. According to Antibiotic assay and production amount comparison, results expressed a ratio of development of production in SSF conditions to SLF conditions. Regarding previous studies on a solid state fermenter and its advantages, in this study, convenience of SSF conditions compared to SLF conditions was experimented. Also mentioning that maintaining the condition of solid state fermenter is more comfortable and practical than liquid state fermenter, using a solid based fermenter to produce antibiotics, especially CPC, can be appropriate. Considering appropriate control conditions of SSF to produce secondary metabolites, decrease in expenses, and increase of production, taking advantage of it in order to increase production parallel to modern methods, such as genetically manipulating CPC producing microorganisms are recommended to pharmacological industries. Also, to make this method applicable, further studies in industrial criterion seem necessary.

Background: Biofilm formation is a major virulence factor in different bacteria. Biofilms allow bacteria to resist treatment with antibacterial agents. The biofilm formation on glass and steel surfaces, which are extremely useful surfaces in food industries and medical devices, has always had an important role in the distribution and transmission of infectious diseases. Objectives: In this study, the effect of coating glass and steel surfaces by copper nanoparticles (CuNPs) in inhibiting the biofilm formation by Listeria monocytogenes and Pseudomonas aeruginosa was examined. Materials and Methods: The minimal inhibitory concentrations (MICs) of synthesized CuNPs were measured against L. monocytogenes and P. aeruginosa by using the broth-dilution method. The cell-surface hydrophobicity of the selected bacteria was assessed using the bacterial adhesion to hydrocarbon (BATH) method. Also, the effect of the CuNP-coated surfaces on the biofilm formation of the selected bacteria was calculated via the surface assay. Results: The MICs for the CuNPs according to the broth-dilution method were ≤ 16 mg/L for L. monocytogenes and ≤ 32 mg/L for P. aeruginosa. The hydrophobicity of P. aeruginosa and L. monocytogenes was calculated as 74% and 67%, respectively. The results for the surface assay showed a significant decrease in bacterial attachment and colonization on the CuNP-covered surfaces. Conclusions: Our data demonstrated that the CuNPs inhibited bacterial growth and that the CuNP-coated surfaces decreased the microbial count and the microbial biofilm formation. Such CuNP-coated surfaces can be used in medical devices and food industries, although further studies in order to measure their level of toxicity would be necessary.

Respiratory viral infection is the main cause of exacerbations of chronic obstructive pulmonary disease (COPD) in all age groups. The present study aimed to find out the association between viral infection in exacerbated and stable patients with COPD as well as evaluating the frequency of respiratory viruses in the Iranian exacerbated patients.The study included 170 patients as the sample group with acute exacerbations and a control group consisting of 96 stable patients over a period of 3 years. Reverse transcription- nested polymerase chain reaction (RT-nested PCR) and nested PCR methods were used to diagnose the presence of 16 respiratory viruses.Viral infection was detected in 81 (47.6%) exacerbations and 24 (25%) stable patients (p0.05). Adenovirus was more frequent among the exacerbated patients than the stable patients (p0.05). Furthermore, influenza virus, respiratory syncytial virus, and enterovirus turned out to be the most common viruses in both groups. Moreover, respiratory viral co-infection has a possible role in exacerbation, severity, and longer hospitalization. Muscle pain and fever were found as significant symptoms in the infected patients with exacerbations.The current study investigated the probable roles of the respiratory viruses, and dual infections during acute exacerbations of COPD. Since climate-dependent respiratory viral incidence patterns in Iran are often dissimilar, preparing a comprehensive global model of respiratory infections with seasonal details in different geographical zones might decrease the morbidity and mortality rate in exacerbations of COPD.

BACKGROUND Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide and the association between HPV infection and genital cancers has been well established. This study concerned the possible role of HPV infection in colorectal carcinoma (CRC) in the Iranian population. MATERIALS AND METHODS We examined 80 tissues obtained from patients with colorectal cancer consisting of 58 colon cancer samples and 22 rectal cancer samples and 80 tissues from patients with unremarkable pathologic changes as matched controls by sex, study center and anatomical sites. HPV infection and genotypes were detected using nested PCR and sequencing methods, respectively. RESULTS HPV DNA was detected in 5/80 (6.25%) cases including 1 of 22 (4.54%) patients with rectum cancer and 4 of 58 (6.9%) patients with colon cancer and 1/80 (1.25%) of controls. Furthermore, HPV-18 was detected as the most frequent type and we found no significant correlation between prevalence of HPV infection and anatomical sub- sites. CONCLUSIONS Although a causal relation between human papillomavirus and colorectal cancer was not found through this study, analysis of medical records pointed to a possible role for high- risk types of HPV in increasing the potential of aggressiveness in colorectal cancer. This study shows a particular frequency of HPV genotypes in patients with colorectal cancer in Iran. Since HPV vaccines are limited to a few types of virus, using cohort studies in different geographical zones to screen for patterns of HPV infection in different organs might increase the efficacy and optimization of the current vaccines.

Background: The role of inflammation in prostate diseases is suggested by the presence of inflammatory cells within the prostate in benign prostatic hyperplasia (BPH) and prostate cancer (PCa) patients. In addition, bacterial and viral infection may lead to chronic and recurrent inflammation of the prostate. The human papillomaviruses (HPVs) are a family of sexually transmitted viruses which have been implicated in the aetiology of cervical cancer and several other malignancies. This study evaluated the frequency of HPV infection in individuals with prostatic disease in Iran. Materials and Methods: The study included formalin fixed paraffin- embedded tissue samples of 196 primary prostate cases, including 29 PCa and 167 BPH samples. HPV DNA was purified and amplified through MY09/MY11 and GP5+/GP6+ primers with nested PCR. All patients were interviewed using a questionnaire to collect demographic information. Results: Nested PCR showed that HPV DNA was found in 17.2 percent of PCa samples and 4.8 percent of BPH samples (not significant). Conclusions: Our data do not support a significant role of HPV infection in prostatic disease in Iranian patients, but demographic data indicated a probable association between presence of HPV DNA and risk of inflammation in prostate tissue which might lead to prostate carcinoma. Further studies are required to elucidate any roles of HPV infection in prostatic disease.