Dispersal history of SARS-CoV-2 in Galicia, Spain.

The dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron-BA.1 variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the United States became increasingly significant. The number of detected introductions varied from 96 and 101 for Alpha and Delta to 39 for Omicron-BA.1. Most of these introductions left a low number of descendants (<10), suggesting a limited impact on the evolution of the pandemic in Galicia. Notably, Galicia's major coastal cities emerged as critical hubs for viral transmission, highlighting their role in sustaining and spreading the virus. This research emphasizes the critical role of regional connectivity in the spread of SARS-CoV-2 and offers essential insights for enhancing public health strategies and surveillance measures.

The Modification of the Illumina® CovidSeq™ Workflow for RSV Genomic Surveillance: The Genetic Variability of RSV during the 2022-2023 Season in Northwest Spain.

There is growing interest in the molecular surveillance of the Respiratory Syncytial Virus and the monitorization of emerging mutations that could impair the efficacy of antiviral prophylaxis and treatments. A simple, scalable protocol for viral nucleic acid enrichment could improve the surveillance of RSV. We developed a protocol for RSV-A and B amplification based on the Illumina CovidSeq workflow using an RSV primer panel. A total of 135 viral genomes were sequenced from nasopharyngeal samples through the optimization steps of this panel, while an additional 15 samples were used to test the final version. Full coverage of the G gene and over 95% of the coverage of the F gene, the target of the available RSV antivirals or monoclonal antibodies, were obtained. The F:K68N mutation, associated with decreased nirsevimab activity, was detected in our facility. Additionally, phylogenetic analysis showed several sublineages in the 2022-2023 influenza season in Europe. Our protocol allows for a simple and scalable simultaneous amplification of the RSV-A and B whole genome, increasing the yield of RSV sequencing and reducing costs. Its application would allow the world to be ready for the detection of arising mutations in relation to the widespread use of nirsevimab for RSV prevention.

In vivo monitoring of Lactiplantibacillus plantarum in the nasal and vaginal mucosa using infrared fluorescence.

Lactic acid bacteria (LAB) of the genus Lactiplantibacillus have been explored as potential mucosal vaccine vectors due to their ability to elicit an immune response against expressed foreign antigens and to their safety. However, tools for monitoring LAB distribution and persistence at the mucosal surfaces are needed. Here, we characterize Lactiplantibacillus plantarum bacteria expressing the infrared fluorescent protein IRFP713 for exploring their in vivo distribution in the mucosa and potential use as a mucosal vaccine vector. This bacterial species is commonly used as a vaginal probiotic and was recently found to have a niche in the human nose. Three different fluorescent L. plantarum strains were obtained using the nisin-inducible pNZRK-IRFP713 plasmid which contains the nisRK genes, showing stable and constitutive expression of IRFP713 in vitro. One of these strains was further monitored in BALB/c mice using near-infrared fluorescence, indicating successful colonization of the nasal and vaginal mucosae for up to 72 h. This study thus provides a tool for the in vivo spatiotemporal monitoring of lactiplantibacilli, allowing non-invasive bacterial detection in these mucosal sites. KEY POINTS: • Stable and constitutive expression of the IRFP713 protein was obtained in different L. plantarum strains. • IRFP713+ L. plantarum 3.12.1 was monitored in vivo using near-infrared fluorescence. • Residence times observed after intranasal and vaginal inoculation were 24-72 h.

[Historical perspective of mass spectrometry in microbiology]. / Perspectiva histórica de la espectrometría de masas en microbiología.

La espectrometría de masas (EM) es una técnica de análisis que permite caracterizar muestras midiendo las masas (estrictamente las razones masa-carga) de las moléculas componentes. Cuenta con más de un siglo de historia y evolución tecnológica y a lo largo de los años ha ampliado su alcance desde los isótopos a moléculas pequeñas, moléculas orgánicas más complejas y, en las últimas décadas, macromoléculas (ácidos nucleicos y proteínas). La EM MALDI-TOF (matrix-assisted laser desorption ionization time-of-flight) es una variante que permite el análisis de mezclas complejas de proteínas y que se ha aplicado recientemente a la identificación de microorganismos en cultivo, convirtiéndose en una herramienta rápida y eficaz para el diagnóstico microbiológico que ha conseguido entrar en poco tiempo en la rutina de muchos servicios de microbiología clínica. El gran impacto que ha tenido está impulsando el desarrollo de nuevas aplicaciones en el campo de la microbiología clínica.

Relation of Skin Flora of Hands with Glove Perforation and Contamination in Cardiac Surgery.

BACKGROUND AND OBJECTIVES: Surgical scrub reduces the number of microorganisms, but fails to sterilize hands, and therefore the use of sterile gloves is recommended. Glove perforation allows bacteria passage from the surgeons´ hands to the patient´s tissues. We analyze the relationship between skin flora of hands, glove perforation and contamination. METHODS: A prospective study comprising 139 patients undergoing open heart surgery through a median sternotomy was conducted. Surgeons´hands were studied. Gloved and ungloved fingertips were placed on culture plates after scrubbing and before sternal closure. Removed gloves were evaluated for perforations. Samples from the surgical wound were taken for culture. Identification of isolated microorganisms was performed by conventional biochemical tests. RESULTS: Culture of fingertips after scrubbing resulted positive in 29.13% of the samples and increased to 34.53% at the end of the procedure. Culture of gloved fingertips before closing the sternum demonstrated contamination of the outer surface in 11.87% of samples. Gloves removed before sternal closure showed perforations in 23.02% of samples. Holes were observed in 33% of contaminated gloves. No relationship between perforation and contamination of gloves was observed. The culture of the sternal wound resulted positive in 7.91% of cases. A significant relationship between the presence of microorganisms in the wound and glove contamination was demonstrated. (P<0,001). CONCLUSIONS: Perforation does not cause significant contamination of the outer surface of surgical gloves. The statistical correlation between glove contamination and surgical wound colonization could be explained by the presence of other sources of contaminating microorganisms.

Dispersal history of SARS-CoV-2 in Galicia, Spain.

The dynamics of SARS-CoV-2 transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the USA became increasingly significant. Notably, Galicia's major coastal cities emerged as critical hubs for viral transmission, highlighting their role in sustaining and spreading the virus. This research emphasizes the critical role of regional connectivity in the spread of SARS-CoV-2 and offers essential insights for enhancing public health strategies and surveillance measures.

Influence of perinatal and childhood exposure to tobacco and mercury in children's gut microbiota.

Background: Early life determinants of the development of gut microbiome composition in infants have been widely investigated; however, if early life pollutant exposures, such as tobacco or mercury, have a persistent influence on the gut microbial community, its stabilization at later childhood remains largely unknown. Objective: In this exposome-wide study, we aimed at identifying the contribution of exposure to tobacco and mercury from the prenatal period to childhood, to individual differences in the fecal microbiome composition of 7-year-old children, considering co-exposure to a width of established lifestyle and clinical determinants. Methods: Gut microbiome was studied by 16S rRNA amplicon sequencing in 151 children at the genus level. Exposure to tobacco was quantified during pregnancy through questionnaire (active tobacco consumption, second-hand smoking -SHS) and biomonitoring (urinary cotinine) at 4 years (urinary cotinine, SHS) and 7 years (SHS). Exposure to mercury was quantified during pregnancy (cord blood) and at 4 years (hair). Forty nine other potential environmental determinants (12 at pregnancy/birth/infancy, 15 at 4 years and 22 at 7 years, such as diet, demographics, quality of living/social environment, and clinical records) were registered. We used multiple models to determine microbiome associations with pollutants including multi-determinant multivariate analysis of variance and linear correlations (wUnifrac, Bray-Curtis and Aitchison ß-diversity distances), single-pollutant permutational multivariate analysis of variance adjusting for co-variates (Aitchison), and multivariable association model with single taxa (MaAsLin2; genus). Sensitivity analysis was performed including genetic data in a subset of 107 children. Results: Active smoking in pregnancy was systematically associated with microbiome composition and ß-diversity (R2 2-4%, p < 0.05, Aitchison), independently of other co-determinants. However, in the adjusted single pollutant models (PERMANOVA), we did not find any significant association. An increased relative abundance of Dorea and decreased relative abundance of Akkermansia were associated with smoking during pregnancy (q < 0.05). Discussion: Our findings suggest a long-term sustainable effect of prenatal tobacco exposure on the children's gut microbiota. This effect was not found for mercury exposure or tobacco exposure during childhood. Assessing the role of these exposures on the children's microbiota, considering multiple environmental factors, should be further investigated.

Susceptibility trends of Bacteroides fragilis group and characterisation of carbapenemase-producing strains by automated REP-PCR and MALDI TOF.

Susceptibility testing of clinical isolates of anaerobic bacteria is not considered, often, mandatory in routine clinical practice and the treatments are empirically established. Thus, periodic monitoring of the susceptibility patterns of anaerobic bacteria is advisable. The aim of this study was to update on resistance of Bacteroides fragilis group in our Institution with special attention to carbapenems reporting metallo-beta-lactamase producing strains for the first time in Spain, and to compare fingerprinting analysis results obtained by using automated rep-PCR (DiversiLab System) and MALDI-TOF MS. A total of 830 non-duplicated clinical isolates of the B. fragilis group recovered from the years 2006 to 2010 were studied. B. fragilis was the most prevalent species (59.5%). The total susceptibility of B. fragilis group isolates were: penicillin, 13.3%; amoxicillin/clavulanic, 89.6%; piperacillin-tazobactam, 91.8%; cefoxitin, 65.8%; ertapenem, 95.9%; imipenem, 98.2%; clindamycin, 53.4% and metronidazole, 96.4%. The percentage of sensitive isolates did not change significantly over time for amoxicillin/clavulanic, cefoxitin, clindamycin and metronidazole. A slight increase in the rate of resistance to ertapenem and imipenem was observed. Imipenem resistance and carbapenemase production were detected for the first time in our laboratory in the year 2007. No other report of carbapenemase-producing B. fragilis in our country has been previously published. Six imipenem-resistant isolates were MBL-producing and PCR positive for cfiA gene. Four of them were PCR positive for IS-like immediately upstream cfiA gene and two of them were negative. Both, automated rep-PCR (DiversiLab) and MALDI-TOF MS, revealed a great genetic diversity among carbapenem-producing strains suggesting the acquisition of novel resistance genes more than clonal dissemination of them. Both methods seem to be useful tools for fast and accurate identification and strain typing of B. fragilis group in the daily laboratory routine. Because of the relevant increase observed in Bacteroides species isolated from blood cultures and the appearance of carbapenemase-producing strains in our Institution, we recommend to test the antimicrobial susceptibility of the isolates, at least in the most severe patients.

Limited genomic reconstruction of SARS-CoV-2 transmission history within local epidemiological clusters.

A detailed understanding of how and when severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission occurs is crucial for designing effective prevention measures. Other than contact tracing, genome sequencing provides information to help infer who infected whom. However, the effectiveness of the genomic approach in this context depends on both (high enough) mutation and (low enough) transmission rates. Today, the level of resolution that we can obtain when describing SARS-CoV-2 outbreaks using just genomic information alone remains unclear. In order to answer this question, we sequenced forty-nine SARS-CoV-2 patient samples from ten local clusters in NW Spain for which partial epidemiological information was available and inferred transmission history using genomic variants. Importantly, we obtained high-quality genomic data, sequencing each sample twice and using unique barcodes to exclude cross-sample contamination. Phylogenetic and cluster analyses showed that consensus genomes were generally sufficient to discriminate among independent transmission clusters. However, levels of intrahost variation were low, which prevented in most cases the unambiguous identification of direct transmission events. After filtering out recurrent variants across clusters, the genomic data were generally compatible with the epidemiological information but did not support specific transmission events over possible alternatives. We estimated the effective transmission bottleneck size to be one to two viral particles for sample pairs whose donor-recipient relationship was likely. Our analyses suggest that intrahost genomic variation in SARS-CoV-2 might be generally limited and that homoplasy and recurrent errors complicate identifying shared intrahost variants. Reliable reconstruction of direct SARS-CoV-2 transmission based solely on genomic data seems hindered by a slow mutation rate, potential convergent events, and technical artifacts. Detailed contact tracing seems essential in most cases to study SARS-CoV-2 transmission at high resolution.

In vitro neutralizing activity of BNT162b2 mRNA-induced antibodies against full B.1.351 SARS-CoV-2 variant.

SARS-CoV-2 variation represents a serious challenge to current COVID-19 vaccines. Recent reports suggest that B.1.351 and other variants may escape the neutralization activity of the antibodies generated by current vaccines. Ninety-nine healthcare workers undertaking BNT162b2 mRNA vaccination were sampled at baseline, on the day of the second dose, and 14 days after the latter. Neutralization activity against SARS-CoV-2 B.1, B.1.1.7 and B.1.351 was investigated using a Vero-E6 model. Eleven of the study participants had prior infection with SARS-CoV-2. Neutralization titers against the B.1 and the B.1.1.7 variants were not statistically different and were significantly higher than titers against the B.1.351 variant across pre-exposed and non-pre-exposed vaccinated individuals (p < .01). While all vaccinated individuals presented neutralizing antibodies against B.1 and B 1.1.7 after the second dose, 14% were negative against B.1.351 and 76% had low titers (1/201/80). Pre-exposed vaccinated individuals showed higher titers than non-pre-exposed after the first (median titers of 1/387 versus 1/28, respectively) and the second doses (1/995 versus 1/703, respectively). As high as 72% of the pre-exposed vaccines presented titers >1/80 after a single dose, while only 11% of non-exposed vaccinated individuals had titers >1/80. BNT162b2 mRNA-induced antibodies show a lower in vitro neutralizing activity against B.1.351 variant compared to neutralization against B.1.1.7 or B.1 variants. Interestingly, for individuals pre-exposed to SARS-CoV-2, one dose of BNT162b2 mRNA may be adequate to produce neutralizing antibodies against B.1.1.7 and B.1, while two doses of BNT162b2 mRNA provide optimal neutralizing antibody response against B.1.351 too.

Efficacy and Safety of Lithium Treatment in SARS-CoV-2 Infected Patients.

At the beginning of the pandemic, we observed that lithium carbonate had a positive effect on the recovery of severely ill patients with COVID-19. Lithium is able to inhibit the replication of several types of viruses, some of which are similar to the SARS-CoV-2 virus, increase the immune response and reduce inflammation by preventing or reducing the cytokine storm. Previously, we published an article with data from six patients with severe COVID-19 infection, where we proposed that lithium carbonate could be used as a potential treatment for COVID-19. Now, we set out to conduct a randomized clinical trial number EudraCT 2020-002008-37 to evaluate the efficacy and safety of lithium treatment in patients infected with severe SARS-CoV-2. We showed that lithium was able to reduce the number of days of hospital and intensive care unit admission as well as the risk of death, reduces inflammatory cytokine levels by preventing cytokine storms, and also reduced the long COVID syndromes. We propose that lithium carbonate can be used to reduce the severity of COVID-19.

Emergence in Spain of a multidrug-resistant Enterobacter cloacae clinical isolate producing SFO-1 extended-spectrum beta-lactamase.

Between February 2006 and October 2009, 38 patients in different wards at the A Coruña University Hospital (northwest Spain) were either infected with or colonized by an epidemic, multidrug-resistant (MDR), and extended-spectrum-ß-lactamase (ESBL)-producing strain of Enterobacter cloacae (EbSF), which was susceptible only to carbapenems. Semiautomated repetitive extragenic palindromic sequence-based PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE) analysis revealed that all of the E. cloacae isolates belonged to the same clone. Cloning and sequencing enabled the detection of the SFO-1 ESBL in the epidemic strain and the description of its genetic environment. The presence of the ampR gene was detected upstream of bla(SFO-1), and two complete sequences of IS26 surrounding ampR and ampA were detected. These IS26 sequences are bordered by complete left and right inverted repeats (IRL and IRR, respectively), which suggested that they were functional. The whole segment flanked by two IS26 copies may be considered a putative large composite transposon. A gene coding for aminoglycoside acetyltransferase (gentamicin resistance gene [aac3]) was found downstream of the 3' IS26. Despite the implementation of strict infection control measures, strain EbSF spread through different areas of the hospital. A case-control study was performed to assess risk factors for EbSF acquisition. A multivariate analysis revealed that the prior administration of ß-lactam antibiotics, chronic renal failure, tracheostomy, and prior hospitalization were statistically associated with SFO-1-producing E. cloacae acquisition. This study describes for the first time an outbreak in which an SFO-1-producing E. cloacae strain was involved. Note that so far, this ß-lactamase has previously been isolated in only a single case of E. cloacae infection in Japan.

[Variability in HIV viral tropism determination using different genotypic algorithms in patients infected with B versus non-B HIV-1 subtypes]. / Variabilidad en la determinación del tropismo viral del VIH utilizando diferentes algoritmos genotípicos de interpretación en pacientes VIH-1 infectados con subtipos B versus no-B.

BACKGROUND: Genotypic tools based on the analysis of the V3 region are seen as an alternative to phenotypic assays for viral tropism determination before prescribing maraviroc. The concordance between different genotypic algorithms has been evaluated in HIV+ patients infected with B versus non-B subtypes. METHODS: HIV-infected patients on regular follow up at Hospital Universitario de Santiago de Compostela (Spain) were selected. The env-V3 region was sequenced from plasma samples and viral tropism was estimated using 8 different genotypic algorithms. Concordance among predictors was statistically evaluated by the calculation of the kappa index. Phylogenetic analyses were performed to determine the genetic subtype. RESULTS: A total of 92 HIV-infected patients were selected, 72 B and 20 non-B subtypes. Regarding the B subtype group, significant kappa values were obtained among all 28 possible combinations between the genotypic predictors evaluated. The best concordance among non-related predictors was observed for webPSSM(SINSI)/Wetcat(PART) (k: 0.771) and webPSSM(SINSI)/geno2pheno (k: 0.574). Conversely, among non-B subtypes, a significative kappa index was only obtained for 13 combinations. Among non-B subtypes, the best concordance values were obtained for webPSSM(X4R5)/Wetcat(PART) (k: 0.600) and webPSSM(SINSI)/Charge rule (k: 0.590). CONCLUSION: A high concordance was observed between different genotypic algorithms to determine viral tropism among HIV-1 B subtypes infected patients, especially between webPSSM(SINSI) and geno2pheno or Wetcat. Conversely, the overall concordance among non-B subtypes was lower. This heterogeneity could be justified by the low prevalence of non B subtypes in the datasets in which the genotypic tropism predictors were trained.

[Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry vs conventional methods in the identification of Candida non-albicans]. / Espectrometría de masas matrix-assisted laser desorption ionization time-of-flight vs. metodología convencional en la identificación de Candida no-albicans.

INTRODUCTION: Candida infection has become a major health problem worldwide. The epidemiology of Candidaemia has substantially changed by the emergence of the species Candida non-albicans. This variation is particularly important in the choice of prophylaxis and empirical treatment. The methods based on biochemical and molecular biology have limitations for the correct identification of Candida species. The aim of this study is to demonstrate the ability of the MALDI-TOF mass spectrometry for the identification of these species and compare it with the technology used today. METHODS: We included all isolates collected over 2 years (n=73) of Candida non-albicans from non-invasive samples. The identification was carried out by Vitek-2 systems YST and API CAUX. The MALDI-TOF identifications were made with Confidence Axima system (Shimadzu Corporation) using the Shimadzu Launchpad software and database SARAMIS (AnagnosTec GmbH). Discrepancies were resolved by SeptiFast LightCycler multiplex PCR, specific PCR C. glabrata and enzymatic digestion with BanI SADH fragment in isolates of C. parapsilosis. RESULTS: Of the 73 isolates of Candida non-albicans, the biochemical methods conclusively identified 67 to species level and 6 at the genus level. The MALDI-TOF system obtained identifications at the species level in all cases. The correlation in the species of all isolates studied was 85.07%, reaching 94.52% when the correlation was made between the identification obtained by biochemical methods and the methods for the analysis of the discrepancies. In isolates of C. parapsilosis, MALDI-TOF system obtained an identification of C. orthopsilosis. In 3 of them it was confirmed by digestion with BanI SADH fragment. CONCLUSION: This study has demonstrated the use of mass spectrometry (MALDI-TOF system) to provide the microbiology laboratory with greater efficiency and reliability to identify isolates of Candida non-albicans to species level. It also shows its potential usefulness in identifying related species, such as C. parapsilosis, metapsilosis and orthopsilosis.

The fate of SARS-COV-2 in WWTPS points out the sludge line as a suitable spot for detection of COVID-19.

SARS-CoV-2 genetic material is detectable in the faeces of a considerable part of COVID-19 cases and hence, in municipal wastewater. This fact was confirmed early during the spread of the COVID-19 pandemic and prompted several studies that proposed monitoring its incidence by wastewater. This paper studies the fate of SARS-CoV-2 genetic material in wastewater treatment plants using RT-qPCR with a two-fold goal: i) to check its presence in the water effluent and in the produced sludge and ii) based on the understanding of the virus particles fate, to identify the most suitable spots for detecting the incidence of COVID-19 and monitor its evolution. On the grounds of the affinity of enveloped virus towards biosolids, we hypothesized that the sludge line acts as a concentrator of SARS-CoV-2 genetic material. Sampling several spots in primary, secondary and sludge treatment at the Ourense (Spain) WWTP in 5 different days showed that, in effect, most of SARS-CoV-2 particles cannot be detected in the water effluent as they are retained by the sludge line. We identified the sludge thickener as a suitable spot for detecting SARS-CoV-2 particles thanks to its higher solids concentration (more virus particles) and longer residence time (less sensitive to dilution caused by precipitation). These findings could be useful to develop a suitable strategy for early warning of COVID-19 incidence based on WWTP monitoring.

Potential clinical utility of polymerase chain reaction in microbiological testing for sepsis.

OBJECTIVES: To evaluate the potential improvement of antimicrobial treatment by utilizing a new multiplex polymerase chain reaction (PCR) assay that identifies sepsis-relevant microorganisms in blood. DESIGN: Prospective, observational international multicentered trial. SETTING: University hospitals in Germany (n = 2), Spain (n = 1), and the United States (n = 1), and one Italian tertiary general hospital. PATIENTS: 436 sepsis patients with 467 episodes of antimicrobial treatment. METHODS: Whole blood for PCR and blood culture (BC) analysis was sampled independently for each episode. The potential impact of reporting microorganisms by PCR on adequacy and timeliness of antimicrobial therapy was analyzed. The number of gainable days on early adequate antimicrobial treatment attributable to PCR findings was assessed. MEASUREMENTS AND MAIN RESULTS: Sepsis criteria, days on antimicrobial therapy, antimicrobial substances administered, and microorganisms identified by PCR and BC susceptibility tests. RESULTS: BC diagnosed 117 clinically relevant microorganisms; PCR identified 154. Ninety-nine episodes were BC positive (BC+); 131 episodes were PCR positive (PCR+). Overall, 127.8 days of clinically inadequate empirical antibiotic treatment in the 99 BC+ episodes were observed. Utilization of PCR-aided diagnostics calculates to a potential reduction of 106.5 clinically inadequate treatment days. The ratio of gainable early adequate treatment days to number of PCR tests done is 22.8 days/100 tests overall (confidence interval 15-31) and 36.4 days/100 tests in the intensive care and surgical ward populations (confidence interval 22-51). CONCLUSIONS: Rapid PCR identification of microorganisms may contribute to a reduction of early inadequate antibiotic treatment in sepsis.

The role of the gut microbiota in schizophrenia: Current and future perspectives.

OBJECTIVES: Schizophrenia is a poorly understood chronic disease. Its pathophysiology is complex, dynamic, and linked to epigenetic mechanisms and microbiota involvement. Nowadays, correlating schizophrenia with the environment makes sense owing to its multidimensional implications: temporal and spatial variability. Microbiota involvement and epigenetic mechanisms are factors that are currently being considered to better understand another dimension of schizophrenia. METHODS: This review summarises and discusses currently available information, focussing on the microbiota, epigenetic mechanisms, technological approaches aimed at performing exhaustive analyses of the microbiota, and psychotherapies, to establish future perspectives. RESULTS: The connection between the microbiota, epigenetic mechanisms and technological developments allows for formulating new approaches objectively oriented towards the development of alternative psychotherapies that may help treat schizophrenia. CONCLUSIONS: In this review, the gut microbiota and epigenetic mechanisms were considered as key regulators, revealing a potential new aetiology of schizophrenia. Likewise, continuous technological advances (e.g. culturomics), aimed at the microbiota-gut-brain axis generate new evidence on this concept.

The future of HIV infection: gene therapy and RNA interference.

The description of the mechanism of RNA interference (RNAi) has generated enormous interest in the biomedical field. A previously unrecognized pathway in which small interfering, 21 to 23 mer, double-stranded RNA (siRNA) mediates sequence-specific degradation of mRNA is becoming one the most useful techniques in cell biology and genetics research. Based on the potency, specificity and physiology of RNAi to silence gene expression, much is expected from its use as a therapeutic tool. The first evidence of RNAi as a suppressor of HIV replication has already been reported, thus providing a new impetus to the development of molecular or gene therapy approaches to HIV infection.

Total HCV core antigen assay. A new marker of HCV viremia and its application during treatment of chronic hepatitis C.

The present study assesses the clinical usefulness of the hepatitis C core antigen assay for monitoring of patients being treated for chronic hepatitis C virus (HCV) infection. Eighty-six serum samples were selected at random from 16 patients and levels of HCV RNA and HCV core antigen were determined simultaneously and in parallel to compare both techniques. The data obtained were compared by Pearson's correlation and the coefficients calculated by Fisher transformation and by calculating the difference and standard error. A good linear correlation was observed between both techniques. Maximum correlation, with significant difference, was found between patients infected with the 1a genotype and other genotypes. In conclusion, the HCV core antigen assay is useful for the diagnosis of early infection; however, its use for determining the exact timing of viral elimination during treatment is clearly unsuitable.