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Rotavirus is the leading cause of severe acute gastroenteritis among children worldwide. It is well known that breast-feeding and vaccination afford infants protection. Since breast-feeding has drastically decreased in developed countries, efforts have been focused on the potential use of probiotics as preventive agents. In this study, a novel Bifidobacterium longum subsp. infantis strain was isolated from infant feces and selected, based on its capacity to inhibit in vitro rotavirus Wa replication (up to 36.05% infectious foci reduction) and also to protect cells from virus infection (up to 48.50% infectious foci reduction) in both MA-104 and HT-29 cell lines. Furthermore, studies using a BALB/c mouse model have proved that this strain provides preliminary in vivo protection against rotavirus infection. The strain has been deposited in the Spanish Type Culture Collection under the accession number CECT 7210. This novel strain has the main properties required of a probiotic, such as resistance to gastrointestinal juices, biliary salts, NaCl, and low pH, as well as adhesion to intestinal mucus and sensitivity to antibiotics. The food safety status has been confirmed by the absence of undesirable metabolite production and in acute ingestion studies of mice. Overall, these results demonstrate that Bifidobacterium longum subsp. infantis CECT 7210 can be considered a probiotic able to inhibit rotavirus infection.

The efficacy of recombinant Lactococcus lactis as a delivery vehicle for a rotavirus antigen was evaluated in a mouse model. The rotavirus VP8* protein was expressed intracellularly and extracellularly in L. lactis wild type and in an alr mutant deficient in alanine racemase activity, necessary for the synthesis of the cell-wall component D: -alanine. When the mucosal immune response was evaluated by measuring VP8*-specific IgA antibody in faeces, wild-type L. lactis triggered a low IgA synthesis only when the secreting strain was used. In contrast, VP8*-specific IgA was detected in faeces of both groups of mice orally given the alr mutant expressing extracellular VP8* and intracellular VP8*, which reached levels similar to that obtained with the wild type secreting strain. However, oral administration of the recombinant strains did not induce serum IgG or IgA responses. L. lactis cell-wall mutants may therefore provide certain advantages when low-antigenic proteins are expressed intracellularly. However, the low immune response obtained by using this antigen-bacterial host combination prompts to the use of new strains and vaccination protocols in order to develop acceptable rotavirus immunization levels.

Viruses are among the most common causes of acute gastroenteritis. In recent years, new viruses causing outbreaks of acute gastroenteritis have been described. Among these, Aichi virus was identified in Japan in 1989. Aichi virus belongs to the Kobuvirus genus in the family Picornaviridae . This virus has been detected in outbreaks of gastroenteritis associated with oyster consumption and in pediatric stool samples, but little is known about its epidemiology or pathogenesis. In the present study, the prevalence of antibodies to Aichi virus in a Spanish population was determined between 2007 and 2008 by using an enzyme-linked immunosorbent assay (ELISA). As in previous studies, a high seroprevalence of antibodies to Aichi virus (70%) was observed, with levels differing according to age. We observed significant differences in titers of antibody to Aichi virus among different age groups, grouped by decades. We report high ELISA and neutralizing antibody titers, and both titers fitted a sigmoid curve significantly. However, this virus is seldom detected; therefore, further studies are needed to gain a better understanding of its importance as a pathogenic agent.

SUMMARYWe report the prevalence of rotavirus and calicivirus infections, along with their respective association with diarrhoea in the porcine population of the region of northern Spain. A total of 221 samples were collected at random from different farms in the region and from the main slaughterhouse facility in the city of Zaragoza. Faecal samples were scored as diarrhoeic or normal and grouped into five groups to match general farm management and age criteria: group I (suckling 0–4 weeks), group II (weaning >4–8 weeks), group III (transition >8–16 weeks), group IV (fattening >16–24 weeks) and group V (adults >24 weeks). Group A rotavirus detection and caliciviruses were investigated by reverse transcription–polymerase chain reaction (RT–PCR). Conventional RT–PCR was performed using primers designed to detect rotavirus group A, caliciviruses and/or human noroviruses. A real-time RT–PCR was carried out using TaqMan probes for genogroups GI and GII of noroviruses. Rotaviruses and caliciviruses were detected with an overall prevalence of 16·7% and 12·2%, respectively. Rotavirus detection in faecal samples was associated with both age and faecal consistency, being more frequent in piglets aged

The rotavirus nonstructural NSP4 protein, a transmembrane endoplasmic reticulum-specific glycoprotein, has been described as the first viral enterotoxin. Purified NSP4 or a peptide corresponding to NSP4 residues 114-135 induces diarrhea in young mice. NSP4 has a membrane-destabilizing activity and causes an increase in intracellular calcium levels and chloride secretion by a calcium-dependent signalling pathway in eucaryotic cells. In this study, four recombinant baculoviruses were generated expressing the rotavirus NSP4 glycoprotein from the human strains Wa and Ito, the porcine strain OSU, and the simian strain SA11, which belong to two different NSP4 genotypes, A and B. The recombinant glycoproteins, expressed as polyhistidine-tagged molecules, were analyzed by Western blotting and immunoprecipitation. Newborn mice responded with diarrhea after inoculation with each of the recombinant NSP4 proteins.

11 páginas, 4 figuras., BACKGROUND: Excessive apoptosis induces unwanted cell death and promotes pathological conditions. Drug discovery efforts aimed at decreasing apoptotic damage initially targeted the inhibition of effector caspases. Although such inhibitors were effective, safety problems led to slow pharmacological development. Therefore, apoptosis inhibition is still considered an unmet medical need. METHODOLOGY AND PRINCIPAL FINDINGS: The interaction between Apaf-1 and the inhibitors was confirmed by NMR. Target specificity was evaluated in cellular models by siRNa based approaches. Cell recovery was confirmed by MTT, clonogenicity and flow cytometry assays. The efficiency of the compounds as antiapoptotic agents was tested in cellular and in vivo models of protection upon cisplatin induced ototoxicity in a zebrafish model and from hypoxia and reperfusion kidney damage in a rat model of hot ischemia. CONCLUSIONS: Apaf-1 inhibitors decreased Cytc release and apoptosome-mediated activation of procaspase-9 preventing cell and tissue damage in ex vivo experiments and in vivo animal models of apoptotic damage. Our results provide evidence that Apaf-1 pharmacological inhibition has therapeutic potential for the treatment of apoptosis-related diseases., This work was supported by grants from the Spanish Ministry of Science and Innovation (MICINN - BIO2007-60066, SAF2008-00048, SAF30542-C01-01 and SAF2010-15512), Laboratorios SALVAT, S.A., Fundacio´n Renal Toma´s de Osma, Generalitat Valenciana Prometeo 2010/005 (partially funded with ERDF), Consolider-Ingenio 2010 (MICINN - CSD2008-00005C) and by the Generalitat Valenciana through Prometeo 2014/061. Moure was funded by a predoctoral fellowship from JAE-pre CSIC.

A coronavirus vector based on the genome of the porcine transmissible gastroenteritis virus (TGEV) expressing the rotavirus VP7 protein was constructed to immunize and protect against rotavirus infections in a murine model. The tropism of this TGEV-derived vector was modified by replacing the spike S protein with the homologous protein from mouse hepatitis virus (MHV). The rotavirus gene encoding the VP7 protein was cloned into the coronavirus cDNA. BALB/c and STAT1-deficient mice were inoculated with the recombinant viral vector rTGEVS-MHV-VP7, which replicates in the intestine and spreads to other organs such as liver, spleen and lungs. TGEV-specific antibodies were detected in all the inoculated BALB/c mice, while rotavirus-specific antibodies were found only after immunization by the intraperitoneal route. Partial protection against rotavirus-induced diarrhea was achieved in suckling BALB/c mice born to dams immunized with the recombinant virus expressing VP7 when they were orally challenged with the homotypic rotavirus strain., This study was supported by the CICYT grant SAF2003-01911 from the Spanish Ministry for Science and Technology, the CICYT grant Bio2007-60978, and the European Commission grant PoRRSCon EU-245141. The work of J.M.R. was supported by a “V Segles” fellowship from the University of Valencia.

Noroviruses are the most common cause of outbreaks of viral gastroenteritis worldwide. Norovirus outbreaks were surveyed in Catalonia and the region of Valencia (Eastern Spain) between January 2001 and December 2006 as part of the European Union funded network "Food-borne viruses in Europe". During this time the etiology and epidemiological features of 194 outbreaks of acute non-bacterial gastroenteritis were investigated and norovirus was identified as causing 169 (87.1%) of them. Molecular epidemiology of viral strains was studied by RT-PCR and sequencing part of the RNA polymerase gene in ORF1 from 153 outbreak strains. The most commonly identified norovirus genotype was GII.4 (71.9% of the characterized outbreak strains), which is also the predominant genotype worldwide. During this survey five genetic variants of GII.4 genotype have been sequentially detected and identified as 1996, 2002, 2004, 2006a, and 2006b variants. The transition from one variant to a new one always took place over a short period of time, and thereafter the replacement of strains circulating previously was observed. These new GII.4 variants may have arisen as a consequence of viral evasion from the host immune responses, although apparently there is a lack of long-term immunity after norovirus infections.

Background Acute infectious gastroenteritis causes substantial morbidity and economic loss. Objective The aetiology, epidemiology, and clinical features of acute viral gastroenteritis outbreaks reported during 1 year in Catalonia were investigated. Study Design This was a population-based study in which enzyme immunoassay and reverse transcriptase-polymerase chain reaction (RT-PCR) techniques were used to determine the presence of virus in stool specimens from outbreaks clinically and epidemiologically compatible with a viral aetiology and negative for bacteria, parasites and toxins. Results Sixty outbreaks affecting 1791 people were evaluated. Fifty-five outbreaks were positive for norovirus, four were positive for norovirus and other microorganisms (adenovirus, astrovirus, S. Typhimurium and V. parahaemolyticus in one each). Thirty-seven percentage of the outbreaks occurred in collective catering; 18.3% in nursing homes; 10% in hospitals and long-term-care facilities. Foodborne transmission accounted for 50% of outbreaks. Norovirus genotype GGII.4 accounted for 42% of all the outbreaks, being more prevalent in nursing homes, hospital and long-term-care facilities. Conclusions The large number of norovirus outbreaks and resulting health service demand and absenteeism indicate that acute gastroenteritis caused by norovirus is an important health problem in Catalonia. Preventive measures should target education and control of food handlers, and immediate specific control measures should be adopted in institutions.

The rotavirus non-structural protein 4 (NSP4) has been shown to play a crucial role in rotavirus-induced diarrhea, acting as a viral enterotoxin. It has also been demonstrated that antibody to NSP4 can reduce the severity of rotavirus-induced diarrhea in newborn mice. Two recombinant baculoviruses, expressing the NSP4 protein from the SA11 and Wa rotavirus strains, genotypes A and B, respectively, were used to produce and purify these glycoproteins, which were applied as antigen in an enzyme-linked immunosorbent assay (ELISA) to test the specific antibody response to NSP4 in human sera. Serum samples from 30 children convalescing from a rotavirus infection, from 54 healthy children under 5-years-old, and from 49 adults were tested to determine the presence of antibodies to the viral enterotoxin and to rotavirus structural proteins. Seventy percent of the sera from rotavirus-infected children showed an IgG antibody response to either one or both NSP4 proteins used in this study, although the response was weak. However, IgG antibodies towards either one or both NSP4 proteins were only detected in 26% of the non-convalescent healthy children and in only 18% of the adults. No serum IgA antibodies towards NSP4 were found in this study. IgG antibody recognition of the NSP4 protein from the SA11 and Wa rotavirus strains was not always heterotypic.