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Background: Globally, most people with head and neck cancers (HNCs) are diagnosed with advanced-stage disease. HNC diagnostic stage has multifactorial explanations, with the role of health system factors not yet fully investigated., Methods: HNC centres (n = 18) from the HEADSpAcE Consortium were surveyed via a bespoke health system questionnaire covering a range of factors. Centres were compared using the least square means for the presence/absence of each health system factor to their proportion of advanced-stage HNC., Results: Health system factors associated with lower proportion in advanced-stage diagnosis were formal referral triaging (14%, 95% CI-0.26, -0.03), routine monitoring of time from referral to diagnosis (16%, 95% CI-0.27, -0.05), and fully publicly funded systems (17%, 95% CI-0.29, -0.06). Several health systems factors had no routinely available data., Conclusions: Through identifying and monitoring health systems factors associated with lower proportions of advanced stage HNC, interventions could be developed, and systems redesigned, to improve early diagnosis., (© 2025 The Author(s). Head & Neck published by Wiley Periodicals LLC.)

Understanding the proportion of SARS-CoV-2 patients with Mycoplasmapneumoniae coinfection is crucial for treating patients suffering from coronavirus disease (COVID-19), help to ensure responsible use of antibiotics and minimize the negative consequences of overuse. In addition, this knowledge could have an impact on empirical antibiotic management guidelines for patients with COVID-19. This systematic review aimed to identify the prevalence of M. pneumoniae in patients with coronavirus disease 2019 (COVID-19). A bibliographic search of studies published in Spanish or English was conducted using the PubMed search engine. Fourteen articles from different continents (America, Asia and Europe) were included, involving a total of 5855 patients in these studies. The mean age of COVID-19 patients with M. pneumoniae was 48 years old (range 1-107), most of whom were male. The detection of laboratory-confirmed M. pneumoniae infection varied between 0 and 33.3%. Most of patients referred fever, cough, and dyspnea, and received empirical antibiotic treatment. Bacterial coinfection was not associated with increased ICU admission and mortality. The prevalence of coinfection showed extremely dissimilar figures according to the population studied and diagnostic criteria. However, it is important to develop Latin American studies, given the heterogeneity observed in the studies conducted in different countries. Standardized definitions should be developed in order to be able to assess the impact of coinfections in patients with a diagnosis of COVID-19., (Copyright © 2024 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Bacterial co-pathogens are commonly identified in viral respiratory infections and are important causes of morbid-mortality. The prevalence of Chlamydia (C.) pneumoniae infection in patients infected with SARS-CoV-2 has not been sufficiently studied. The objective of the present review was to describe the prevalence of C. pneumoniae in patients with coronavirus disease 2019 (COVID-19). A search in MEDLINE and Google Scholar databases for English language literature published between January 2020 and August 2021 was performed. Studies evaluating patients with confirmed COVID-19 and reporting the simultaneous detection of C. pneumoniae were included. Eleven articles were included in the systematic review (5 case cross-sectional studies and 6 retrospective studies). A total of 18450 patients were included in the eleven studies. The detection of laboratory-confirmed C. pneumoniae infection varied between 1.78 and 71.4% of the total number of co-infections. The median age of patients ranged from 35 to 71 years old and 65% were male. Most of the studies reported one or more pre-existing comorbidities and the majority of the patients presented with fever, cough and dyspnea. Lymphopenia and eosinopenia were described in COVID-19 co-infected patients. The main chest CT scan showed a ground glass density shadow, consolidation and bilateral pneumonia. Most patients received empirical antibiotics. Bacterial co-infection was not associated with increased ICU admission and mortality. Despite frequent prescription of broad-spectrum empirical antimicrobials in patients with coronavirus 2-associated respiratory infections, there is a paucity of data to support the association with respiratory bacterial co-infection. Prospective evidence generation to support the development of an antimicrobial policy and appropriate stewardship interventions specific for the COVID-19 pandemic are urgently required., (Copyright © 2022 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Human Metapneumovirus (hMPV) is responsible for acute respiratory infections in humans, with clinical and epidemiological relevance in pediatric, elderly, and immunocompromised populations. These features are largely unknown in Córdoba, Argentina and in adults in general. Hence, our goal was to broadly characterize hMPV infection in patients of all ages hospitalized with acute respiratory infections in Córdoba, Argentina, including epidemiology, clinical features and genetic diversity. Nasopharyngeal secretions were obtained from 795 patients during 2011-2013, 621 patients were 0-25 years old and 174 were 26-85 years old. HMPV was assayed by RT-PCR and other respiratory viruses by indirect immunofluorescence. Local strains were identified by sequence analysis. Human Metapneumovirus was detected in 20.3% (161/795) patients, 13.1% as single infections and 7.2% in co-infections, more frequently with Respiratory Syncytial Virus. HMPV circulated during late winter and spring in all age patients, but mainly in children under 4 years old in 71.4% (115/161) and adults between 26 and 59 years old in 12.4% (20/161). The most prevalent diagnosis was mild acute respiratory infection in 59.6% (96/161) and bronchiolitis in 9.3% (15/161). Local strains were clustered within A2 subtype; they presented 73-100% identities among them, showing a high degree of homology compared to isolations from neighboring countries. We demonstrate that hMPV circulated among all age patients with respiratory infection during 2011-2013 in Córdoba, contributing to the understanding of this virus, its diagnosis and patient handling in local health-care centers., Competing Interests: The authors have declared that no competing interests exist.

Background: Human papilloma virus (HPV) is one of the most frequent sexually transmitted infections, especially among young people., Aims: To describe the prevalence of genital HPV infections, to identify clinical-epidemiological factors associated with them and to determine the frequency of viral strains., Methods: Endocervical samples were studied of 505 women between 15 and 49 years old, who attended the laboratory of the Institute of Social Security, residents of Posadas, Misiones, for the study of vaginal exudate, between January 2012 and June 2013. A 450-base pair fragment within the HPV L1 region was amplified. Genotype detection was performed through the study of the restriction fragment length polymorphism (RFLP)., Results: The prevalence of total HPV carriage was 30.7%, and of these 71.6% corresponded to high risk (mainly HPV 16 [35.1%], 58 [10.8%] and 31 [8.1%]). HPV detection was higher in women aged 15 to 24 years (OR: 1.48, 95% CI: 1.01-2.18) and with more sexual partners (OR: 1.81, 95% CI: 1, 02-3.22). There was no association with pregnancy, stability of the couple, contraceptive methods, age at onset of sexual intercourse, or smoking., Conclusions: The identification and typing of HPV in this study provides information regarding the high prevalence of HPV and the substantial proportion of cases with oncogenic genotypes among sexually active women in this region of Argentina.

Aims: The purpose of the present study was to elucidate the presence of human herpesvirus 6A (HHV-6A), HHV-6B and HHV-7 in samples of the uterine cervix through detection of viral DNA. We analysed normal tissues, samples with low-grade squamous intraepithelial lesions (LSILs) and high-grade squamous intraepithelial lesions (HSILs). We correlated the presence of HHV-6 and HHV-7 with the finding of human papillomavirus (HPV) in mucosal samples., Methods: Cervical samples were examined and grouped as follows: group 1 (n=29), normal cytology; group 2 (n=61), samples with LSIL; group 3 (n=35), samples with HSIL. Molecular biology examinations were performed in all samples to detect HHV-6, HHV-7 and HPV DNA and to typify HHV-6 species., Results: Group 1: normal cytology and HPV (-): HHV-6: 6.8% (2/29), HHV-7: 79.3% (23/29); group 2: LSIL and HPV (-): HHV-6: 93.1% (27/29), HHV-7: 96.5% (28/29); LSIL and HPV (+): HHV-6: 0% (0/32), HHV-7: 90.6% (29/32); group 3: HSIL and HPV (-): HHV-6: 20% (2/10), HHV-7: 70% (7/10); HSIL HPV (+): HHV-6: 12% (3/25), HHV-7: 68% (17/25). HHV-6A DNA was not detected in any samples., Conclusions: (1) Both HHV-6 and HHV-7 infect the mucosal cells of the cervix with higher prevalence of HHV-7. (2) The higher prevalence of HHV-6 in LSIL HPV (-) samples compared with those with normal cytology indicates that it constitutes a possible risk factor for atypia production. (3) The presence of HHV-7 in all samples questions its role in the production of atypia. (4) The finding of HHV-6 and HHV-7 suggests that the cervical mucosa is a possible transmission pathway for these viruses., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

In order to determine the presence and genetic diversity of Chlamydia spp. in the north-eastern area of Buenos Aires province, Argentina, conjunctival, oropharyngeal, cloacal swab and tissues were collected from a total of 90 psittacine pet birds of different age and clinical manifestations. Through molecular methods, Chlamydiaceae was detected in 30% (27/90) of the samples, out of which 70.3% (19/27) were positive for Chlamydia psittaci and 14.9% (4/27) for Chlamydia abortus. Nine C. psittaci positive samples were genotyped by ompA gene sequences, 8 clustered within genotype A and 1 within genotype B. A significant association was observed between the presence of Chlamydia spp. and the manifestation of clinical signs compatible with chlamydiosis, as well as with the age of the birds (younger than one year old). This report contributes to the improvement of our understanding of chlamydial agents in our country., (Copyright © 2018 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Objective: Chlamydia trachomatis is the most prevalent bacteria causing sexually transmitted infections. In women, this infection can cause cervicitis and urethritis, although it's usually asymptomatic. The aim of this study was to investigate the prevalence of C. trachomatis in women attending the lab Instituto de Previsión Social and detect the genotypes., Methods: Endocervical samples from 505 symptomatic and asymptomatic women were assayed. It was determined the presence of C. trachomatis by PCR through amplification of a fragment of the cryptic plasmid. Positive samples were genotyped by the partial amplification of the ompA gene and analyzed phylogenetically., Results: Forty-three positive samples were detected to infection with C. trachomatis, obtaining a prevalence of 8.5% (IC 95%: 6.4-11.3%). The prevalence of C. trachomatis was higher in women with vaginal symptoms [11.3% (30/265) vs. 5.4% (13/240)] (p = 0.018), as well as in women under 26 year-old [11.5% (28/244) vs. 6.2% (15/246)] (p = 0.021). Based on phylogenetic analysis, it was observed that 62% of the samples were genotype E, 15% genotype J, 15% genotype D, and 8% genotype F., Conclusions: This work is the first contribution on the molecular epidemiology of C. trachomatis in the Misiones province, Argentina, which shows the rate of prevalence of this bacterium and offers information on circulating genotypes.

Chlamydia trachomatis is the most commonly reported agent of sexually transmitted bacterial infections worldwide. This pathogen frequently leads to persistent, long-term, subclinical infections, which in turn may cause severe pathology in susceptible hosts. This is in part due to the strategies that Chlamydia trachomatis uses to survive within epithelial cells and to evade the host immune response, such as subverting intracellular trafficking, interfering signaling pathways and preventing apoptosis. Innate immune receptors such as toll-like receptors expressed on epithelial and immune cells in the genital tract mediate the recognition of chlamydial molecular patterns. After bacterial recognition, a subset of pro-inflammatory cytokines and chemokines are continuously released by epithelial cells. The innate immune response is followed by the initiation of the adaptive response against Chlamydia trachomatis , which in turn may result in T helper 1-mediated protection or in T helper 2-mediated immunopathology. Understanding the molecular mechanisms developed by Chlamydia trachomatis to avoid killing and host immune response would be crucial for designing new therapeutic approaches and developing protective vaccines. In this review, we focus on chlamydial survival strategies and the elicited immune responses in male genital tract infections., (© 2017 Society for Reproduction and Fertility.)

Pixuna virus (PIXV) is an enzootic member of the Venezuelan Equine Encephalitis Virus complex and belongs to the New World cluster of alphaviruses. Herein we explore the role of the cellular cytoskeleton during PIXV replication. We first identified that PIXV undergoes an eclipse phase consisting of 4 h followed by 20 h of an exponential phase in Vero cells. The infected cells showed morphological changes due to structural modifications in actin microfilaments (MFs) and microtubules (MTs). Cytoskeleton-binding agents, that alter the architecture and dynamics of MFs and MTs, were used to study the role of cytoskeleton on PIXV replication. The virus production was significantly affected (p < 0.05) after treatment with paclitaxel or nocodazole due to changes in the MTs network. Interestingly, disassembly of MFs with cytochalasin D, at early stage of PIXV replication cycle, significantly increased the virus yields in the extracellular medium (p < 0.005). Furthermore, the stabilization of actin network with jasplakinolide had no effect on virus yields. Our results demonstrate that PIXV relies not only on intact MTs for the efficient production of virus, but also on a dynamic actin network during the early steps of viral replication.

Background: Chlamydia trachomatis urogenital infections are the leading cause of sexually transmitted bacterial infections. Although the prevalence of chlamydial infection is similar in men and women, current research is mainly focused on women, neglecting the study of male genital tract infections. We, therefore, investigated Chlamydia infection in the rodent male genital tract., Materials and Methods: Male NOD and C57BL/6 mice were inoculated in the meatus urethra with C. muridarum. Bacterial DNA, leukocyte infiltration of male genital tract tissues, pelvic pain, and Chlamydia-specific immune responses were analyzed at different time points., Results and Conclusions: The inoculation of C. muridarum in the meatus urethra of male mice resulted in an ascending and widely disseminated infection of the male genital tract. C. muridarum remained longer and with the highest bacterial burdens in the prostate, thus showing a special tropism for this organ. Infection caused leukocyte infiltration, mainly composed by neutrophils, and also induced early pelvic pain development that rapidly dropped and resolved as the infection became chronic. Bacterial load and leukocyte infiltration was observed in all prostate lobes, although dorsolateral prostate was the most affected lobe. Interestingly, immune responses induced by both mice strains were characterized by the production of high levels of IL-10 during early stages of the infection, with highest and sustained levels observed in NOD mice, which showed to be less efficient in clearing the infection. Chronic infection of the prostate accompanied by local inflammation and pelvic pain development described herein have important implications for the improvement of the diagnosis and for the design of new efficient therapies. Prostate 77:517-529, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

The aim of this study was to determine whether Human Papillomavirus was present in tongue and periodontium of periodontally healthy and diseased women who had genital lesions caused by the virus. Thirty non-menopausal women, systemically healthy and diagnosed with gynecological HPV lesions, were referred by the Gynecology Service Department of the University Maternal Neonatal Hospital of the City of Cordoba. Anamnesis, oral mucosa examination and periodontal clinical assessment were performed. Three brush samples were taken per patient: two from the same periodontal location (external epithelium of the gum and internal epithelium of the periodontal sulcus/pocket), and the third from the tongue. The 90 samples were submitted to Pap cytology and Polymerase Chain Reaction. The data were statistically analyzed by "Chi Square Test" (χ2) and "Kappa Index" (κ). High prevalence of HPV was found in the tongue (30%) and periodontal tissues (15%). High risk (HR) genotype -16 was detected with the highest percentage (67%), and genotypes -52 and -6 were also detected. Whenever HPV was present in periodontal location, it was also identified in the tongue of the same patients, of whom 88.89% reported that they practiced oral sex. Is worth noting the clinical finding of stomatologic lesions compatible with foliate papillitis in patients with positive intraoral HPV. High prevalence of HPV was found in the female population in Cordoba, with genotype -16 being detected at the highest percentage. No positive correlation was found between HPV and higher incidence and severity of periodontal lesions.

Chlamydia trachomatis (CT) is the most prevalent cause of sexually transmitted diseases. Although the prevalence of chlamydial infection is similar in men and women, current research and screening are still focused on women, who develop the most severe complications, leaving the study of male genital tract (MGT) infection underrated. Herein, we reviewed the literature on genital CT infection with special focus on the MGT. Data indicate that CT certainly infects different parts of the MGT such as the urethra, seminal vesicles, prostate, epididymis and testis. However, whether or not CT infection has detrimental effects on male fertility is still controversial. The most important features of CT infection are its chronic nature and the presence of a mild inflammation that remains subclinical in most individuals. Chlamydia antigens and pathogen recognition receptors (PRR), expressed on epithelial cells and immune cells from the MGT, have been studied in the last years. Toll-like receptor (TLR) expression has been observed in the testis, epididymis, prostate and vas deferens. It has been demonstrated that recognition of chlamydial antigens is associated with TLR2, TLR4, and possibly, other PRRs. CT recognition by PRRs induces a local production of cytokines/chemokines, which, in turn, provoke chronic inflammation that might evolve in the onset of an autoimmune process in genetically susceptible individuals. Understanding local immune response along the MGT, as well as the crosstalk between resident leukocytes, epithelial, and stromal cells, would be crucial in inducing a protective immunity, thus adding to the design of new therapeutic approaches to a Chlamydia vaccine., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

In central area of Argentina, the epidemiologic and molecular characteristics of Chlamydophila psittaci infections are still unknown. Nested polymerase chain reaction of domains II, III, and IV of the omp A gene was used to detect Chlamydophila in 43 pharyngeal swab samples from patients with suspected human psittacosis (2010-2011); 9 (21%) of them yielded positive results. Molecular typing was performed by direct sequencing demonstrating the presence of C. psittaci genotypes A, E/B, and WC., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Bacteria belonging to the family Chlamydiaceae cause a broad spectrum of diseases in a wide range of hosts, including humans, other mammals and birds. However, very little is known about chlamydial infections in birds in our region. In the present study, we examined 28 clinically normal birds in illegal captivity that were confiscated in the province of C6rdoba, Argentina. The objective was to detect Chlamydophila spp. in cloacal swabs by genetic analysis of the ompA gene. Nested-PCR of the ompA gene identified five samples as Chlamydophila pecorum and the sequence analysis demonstrated the presence of the ompA gene of C. pecorum in these birds. On the other hand, Chlamydophila psittaci was not detected. These birds could be either asymptomatic reservoirs or subclinical carriers of C. pecorum. This is the first report of the detection of C. pecorum in Argentina.

Purpose: We investigated Chlamydia trachomatis infection and its pathogenic consequences in the male rodent genital tract., Materials and Methods: Male rats were inoculated in the meatal urethra with Chlamydia muridarum. We sought bacterial DNA at early and late times after inoculation in different parts of the male genital tract. Histological alterations and the immune response against prostate antigens were analyzed., Results: Male rats showed ascending infection with wide dissemination of bacteria in the genital tract at an early time point after inoculation. At later stages bacteria persisted only in some parts of the genital tract and in the prostate gland. C. muridarum was also detected in semen in a high proportion of rats irrespective of an acute or chronic stage of infection. Histological alterations that accompanied C. muridarum were especially observed in the prostate and mainly composed of CD3+ cell infiltration. Positive humoral and cellular responses against prostate antigens were noted in a considerable number of infected rats. NOD mice, an autoimmune, prostatitis prone strain, showed a similar pattern with C. muridarum in the prostate of 100% of infected mice, which was again accompanied by mononuclear cell infiltration and antibodies against prostate antigens at early and late times after inoculation., Conclusions: Results reveal that C. muridarum infects the male rodent genitourinary tract with special persistence in the prostate gland, where it causes chronic inflammation that in turn may act as a trigger factor for self-immune reactions in susceptible hosts., (Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

A wide range of human papillomavirus (HPV) types can infect the anogenital region of males. Although there is a vast knowledge on HPV infections in women as well as on their association with cervical cancer, the study of HPV infections in males is scarce and controversial. The aim of the present work was to detect and typify HPV infections of the anogenital region in males and analyze the associated risk factors in the population studied. Anogenital samples from 37 patients (30 of whom were HIV carriers) attending the Infectology Service at the Hospital Nacional de Clinicas in C6rdoba, Argentina, were studied. Nine of these patients tested HPV-positive and five out of these nine were found to have mixed infections, being 18 and 61 the most frequent genotypes. There was a significant correlation between the HPV-positive patients and those having an HPV-compatible lesion or AIDS. The present work is the first study in the city of Cordoba which contributes relevant results to the knowledge of HPV infection and to the possible implementation of measures for its prevention.

Although Chlamydia infections are widespread throughout the world, data about immunopathogenesis of genitourinary tract infections in males are very limited. In the present work we present an in vitro model of male genital tract-derived epithelial cells, more precisely prostate epithelial cells (PEC), to analyze if they are susceptible and able to respond to Chlamydia muridarum infection. Our results demonstrate that rat PEC are susceptible to C. muridarum infection and respond to this pathogen by up-regulating different proinflammatory cytokine and chemokine genes that could participate in the recruitment and local activation of immune cells, therefore influencing innate and adaptive immune responses during Chlamydia infection. Moreover, we analyzed the expression of Toll-like receptor 4 (TLR4), TLR2, and related molecules on PEC and the effect of C. muridarum infection on their expression. Our results demonstrate that PEC express significant levels of TLR4, CD14, TLR2, and the adaptor molecule MyD88 and up-regulate these proteins in response to C. muridarum infection. Indeed, TLR4, CD14, TLR2, and the adaptor MyD88 are specifically recruited to the vicinity of the bacterial inclusion, suggesting that these TLRs are actively engaged in signaling from this intracellular location in these cells. This is, to our knowledge, the first time that an in vitro model of infection with Chlamydia of male tract-derived epithelial cells has been achieved, and it provides the opportunity to determine how these cells respond and participate in modulating innate and adaptive immune response during Chlamydia infections.

Objectives: The role of Chlamydia trachomatis (CT) in the pathogenesis of chronic prostatitis and its impact on male fertility remain controversial. The aim of this study was to assess the occurrence of chlamydial infection in chronic prostatitis patients and its impact on semen quality., Methods: Urine and semen samples were assayed for the presence of microbial infection. CT-specific IgG and IgA antibodies were measured in serum and seminal plasma. Semen parameter analysis, anti-sperm antibody determinations and inflammatory cytokines measurements were performed., Results: CT was detected in 10% of semen from chronic prostatitis patients. CT-specific IgG and IgA were found in 7.5% and 32.5% of the seminal plasma and in 15.0% and 2.5% of the serum samples from patients. Most of the patients that evidenced CT infection also evidenced CT-specific antibodies either in semen or in serum. We found that chlamydial infection has no detrimental effects on sperm quality. We neither found abnormal levels of serum PSA nor of seminal inflammatory cytokines in CT-infected patients., Conclusions: Our results support the potential role of CT in chronic prostatitis, its importance in diagnosis and that this infection does not seriously compromise sperm quality.

Background: Atherosclerosis is pathogenically similar to a chronic inflammatory response. Peripheral arterial disease (PAD) is a common manifestation of atherosclerosis. Chlamydophila pneumoniae has been suggested to play a role in the origin of PAD., Objective: To determine whether C. pneumoniae is present in atherosclerosis lesions of the carotid artery wall in patients with PAD through several diagnostic methods and to characterize C. pneumoniae susceptibility profiles., Methods: The presence of C. pneumoniae in 9 tissue samples from atherosclerotic lesions obtained by carotid endarterectomy was investigated by 3 methods. Karnofsky-fixed specimens were examined by transmission electron microscopy (TEM), isolation of C. pneumoniae was attempted in LLCMK2 cell structure (ICC), and the presence of chlamydial DNA was investigated by polymerase chain reaction (PCR). The in vitro activities of azithromycin, roxithromycin and penicillin were tested in 4 isolations and the reference strain of C. pneumoniae (AR39)., Results: C. pneumoniae was detected in atherosclerotic plaques from 4 patients with PAD. The pathogen was identified by TEM, PCR and ICC. We report data of the in vitro susceptibility of 4 strains. These strains did not differ from respiratory AR39 strain in their susceptibility patterns to azithromycin, roxithromycin and penicillin., Conclusions: C. pneumoniae is frequently found in the advanced carotid atherosclerotic lesions of patients undergoing endarterectomy. Although these findings do not establish causality in carotid artery atherosclerosis, they should stimulate investigation of the possible causal or pathogenic role of C. pneumoniae. Notably, the profiles of antibiotic susceptibility of C. pneumoniae isolated from 4 of the patients did not differ from those of the reference strain.

Congenital rubella is a persistent infection that contrasts with acute postnatal infection. Basis of the Rubella virus (RV) persistence still remain unknown, though several hypotheses have been postulated. RV induces apoptosis in cell lines, maybe as a way of cell-autonomous defense mechanism against virus. Considering the pattern of c-oncogenes expression during embryogenesis, which promotes proliferation while it inhibits apoptosis in specific cells, at certain times, it can be proposed that when RV infection establishes early in gestation, embryo cells that are proliferating have their apoptotic pathways shut down; then infected proliferating embryo cells cannot execute their apoptotic death program. We here report that RV induces apoptosis in human normal-term placenta chorionic villi explants (CVE) and in monolayers of cytotrophoblasts (CTB), but does not induce apoptosis in primary human embryo fibroblasts (HEF) cultures. These results suggest distinct responses to RV infection when comparing differentiated cells, as CTB, to cells with high proliferating potential, as HEF. RV shoots apoptosis in the former, whereas in fibroblastic dividing cells derived from embryo, RV appears not to be enough stimulus to activate the genetic program of cell death.

In order to facilitate the detection of apoptotic cells (Apo C) in Rubella virus (RV) infected cultures in settings of low resources, we compared hematoxylin and eosin staining (H&E) with the conventional TUNEL technique, and confirmed our findings with DNA electrophoresis and transmission electron microscopy. H&E allowed to distinguish Apo C from non-apoptotic cells. The proportion of Apo C in infected cultures was proportional to the multiplicity of infection (MOI). At a MOI of 10, the percent of Apo C at 3, 4 and 5 days post infection (pi) were 26, 45 and 47%, respectively, which were significantly reduced when the caspase inhibitor z-VAD-fmk was present in the supernatant. By the TUNEL assay, the percent of Apo C in RV-infected cultures were lower (0.8, 1.2 and 1.2% at 3, 4 and 5 days pi, respectively). Our results have shown that H&E staining is an easy, rapid, economic and reproducible method to detect Apo C in RV infected Vero cells cultures. It is possible that H&E makes evident early stages of apoptosis, when an apoptotic cell shows chromatin condensation, nuclear and cytoplasmic contraction (but is still attached to the monolayer), while TUNEL detects later stages of apoptosis because it needs an extensive DNA fragmentation, when apoptotic cells are about to or have already detached from the substratum.

Two monoclonal antibodies (MnAb) directed against the lipopolysaccharide (LPS) and major outer membrane protein (MOMP) of Chlamydia trachomatis were produced for use in indirect immunofluorescence (IFI). The specificity of the antibodies was determined by Dot-blot, Immunoblotting (IB) and IFI onto culture cells infected with C. trachomatis and IFI onto commercial swabs (MRL). The MnAb 2D3 and 3C2 detected LPS and MOMP of C. trachomatis, respectively, by different methods. Neither MnAb showed cross-reactions when other gram-negative bacteria were used as antigens.

The best-known mechanism of action of antibody-mediated virus neutralization is to impede the entrance of viruses to host cells, as determined by neutralization assays. Antibodies may also inhibit the exit of rubella virus (RV) from infected host cells; in this case, the interaction of the antibodies with their domains must occur on the plasma membrane, because antibodies cannot enter the cells. In the present study, we were able to block temporally the exit of virions from RV-infected cells by the binding of monoclonal antibody (mAb) H3 to their surface. The objective was accomplished in three steps: first, we determined the duration of the viral replication cycle; then we established the kinetics of the presence of the domains defined by our mAbs in the cytoplasm of RV-infected VERO cells; and, finally, we assessed the release of viral particles to the supernatant of infected VERO cells in the presence or absence of mAbs or positive and negative mice sera. RV-specific mice sera and mAb H3, which binds to the amino acid sequence 208-239 of the RV-E1 glycoprotein, were able to delay for 24 hours the release of virions from infected cultures, suggesting that the reaction of mAb H3 with its epitope may arrest any change necessary for the assembly and/or release of virions. In conclusion, the neutralizing domain recognized by mAb induces antibodies that can block the viral replication by several mechanisms of action, such as the obstruction of virus entry into cells and the delay of viral release. All of these mechanisms are intimately involved in the critical virus-host cell interactions that allow self-limitation of the infection.

Background and Objectives: Rubella virus (RV) produces a subtle and slow-developing cytopathic effect in Vero cells that is difficult to recognize, especially at low multiplicities of infection. In order to facilitate the detection of RV in cell culture, we standardized a low-pH virus-mediated cell-fusion assay., Study Design: The incubation periods, temperatures, pH and multiplicity of infection were established. The specificity of the method was tested by immunofluorescence assay and cell-fusion inhibition by specific sera., Results: Six days post infection, Vero cells were treated for 5 min with fusion medium. After that, monolayers were incubated with medium at neutral pH for 16 h and then stained. Gigantic cells with multiple nuclei were observed., Conclusions: The method allowed the observation of unequivocal images that are easier to recognize than the cytopathic effect caused by RV in the same cell line. At the same time, the method is simple, accessible and shown to be specific to demonstrate the replication of several strains and isolates of RV in Vero cells.

We studied the presence of a neutralizing epitope of rubella virus (RV) in locally circulating strains in Cordoba, Argentina, using binding by the monoclonal antibody (MAb) H3. This epitope is contained in a sequence of the E1 glycoprotein (E1208-239) represented by the synthetic peptide SP15. H3 MAb showed specific binding to SP15 by enzyme-linked immunosorbent assay (ELISA). One wild-type postnatal isolate, four clones derived from this isolate, and one congenital isolate were reactive with H3 by ELISA. These results suggest that the region of RV represented by SP15 is a domain present in locally circulating strains.

Congenital rubella syndrome (CRS) could be prevented if young women knew their immune status before pregnancy, contributing in this way to decrease the birth morbidity rate due to CRS among the children. Our objective was to optimize the detection of rubella virus-antibodies by HAI, using an easier and safer method to collect samples of big populations. One hundred specimens, obtained from patients in a pediatric hospital and pregnant women in an institute of Virology were used for this work. Venous blood was drawn and collected in a test tube, and few drops were spotted onto filter paper circles. These samples were kept in envelopes and stored at room temperature until analysis. Seventy two percent of dried blood samples had titers identical to those of the corresponding serum samples, and 28% dried blood samples showed 1 dilution of difference. Storage of dried blood at room temperature for 30 days did not affect the HAI titers. Up to 60 days post attainment, 59% dried blood samples had identical titers to those of the corresponding serum samples, and 41% dried blood samples showed one dilution of difference. At 100 days of storage 51% dried blood samples had identical titers to those of the corresponding serum samples, 38% dried blood samples showed 1 dilution of difference and 11% and more than 1 dilution of difference. In conclusion, dried blood on filter paper is an easier method to transport and store blood samples for the determination of rubella virus immunity, for as long as 30 days. It could be used for large-scale epidemiological studies. The sensitivity and specificity of HAI performed on dried blood samples was 100%. Only 0.25 ml of whole blood is needed and the samples are stable at room temperature, without air or sterile conditioning. The proposed methodology is a practical approach to collect, transport and store blood samples. Moreover the blood dried on paper spots can be placed in a plastic bag and mailed to a reference laboratory. This is an appropriate alternative method for serological screenings in developing countries.

There is, apparently, only one serological type of rubella virus (RV) in the population, although several isolates exist with different characteristics. Some authors failed to detect significant differences among RV strains by neutralization, hemagglutination inhibition, and enzyme immunoassay using polyclonal and monoclonal antibodies, but differences in growth, plaque morphology, and temperature sensitivity between vaccine and wild-type strains were shown by Chantler et al. (3) With the purpose of analyzing the possible differences among several strains of RV, we studied the affinity constant of two monoclonal antibodies (MAbs) for two conserved neutralizing epitopes. Wild-type Cordoba (regional isolation of a post-natal infection) and RA 27/3 (vaccine) strains of RV were tested. H3 and H14 MAbs were generated against wild-type Cordoba strain. They defined two epitopes with conserved neutralizing and hemagglutinating activity on both strains. The affinity of the MAbs (expressed as the affinity constant), was greater for Cordoba strain than for RA 27/3. Analyzing the results obtained, we conclude that the neutralizing epitopes defined by our MAbs on E1 glycoprotein are conserved in the two strains, but react with significative different affinities. This could be a way to characterize antigenically different viral strains of the same serotype.

We studied the presence of C. trachomatis-specific IgG and IgM in adults and newborns, respectively, and attempted isolation of the bacteria in cell culture. The determination of antibodies was carried out by an IFA on C. trachomatis infected (L2 434/Bu serotype) McCoy cells, cultured in 24-well plastic plates. We found C. trachomatis-specific IgG in 27% of women with clinical symptoms, in 40% of women being attended for periodic gynecological control, in 60% of infertile women and in 10% of pregnant women. A proportion comparison test revealed the presence of specific IgG as highly significative for the group of infertile women as compared to the group of pregnant women (p < 0.0001). We divided the patients into four groups, in relation to the results of the tests for specific IgG and C. trachomatis isolation. Seven out of 10 had positive isolation and negative IFA, 5 out of 8 had positive isolation and negative IFA. Twenty five out of 28 pregnant women had negative isolation and positive IFA, finally, 63 out of 76 had both tests negative. Statistical analysis using the McNemar proportion-comparison test suggests that IgG's presence is highly significant in pregnant women with respect to other groups (p < 0.001). Our results suggest that the demonstration of IgG is not enough for diagnostic purposes, except in infertile women with a previous history of infection with C. trachomatis. We isolated C. trachomatis in 20% of the newborns tested and 10% were also positive for IgM IFA. The diagnosis was improved by combining both techniques. These results show the importance of the detection of C. trachomatis in youngsters to avoid infertility and in pregnant women to prevent newborn infections and the possibility of premature births and low weight babies.