CCR5 deficiency predisposes to fatal outcome in influenza virus infection.

Influenza epidemics affect all age groups, although children, the elderly and those with underlying medical conditions are the most severely affected. Whereas co-morbidities are present in 50% of fatal cases, 25-50% of deaths are in apparently healthy individuals. This suggests underlying genetic determinants that govern infection severity. Although some viral factors that contribute to influenza disease are known, the role of host genetic factors remains undetermined. Data for small cohorts of influenza-infected patients are contradictory regarding the potential role of chemokine receptor 5 deficiency (CCR5-Δ32 mutation, a 32 bp deletion in the CCR5 gene) in the outcome of influenza virus infection. We tested 171 respiratory samples from influenza patients (2009 pandemic) for CCR5-Δ32 and evaluated its correlation with patient mortality. CCR5-Δ32 patients (17.4%) showed a higher mortality rate than WT individuals (4.7%; P = 0.021), which indicates that CCR5-Δ32 patients are at higher risk than the normal population of a fatal outcome in influenza infection.

Magnet ingestion knows no borders: A threat for Latin American children.

INTRODUCTION AND AIMS: The ingestion of foreign bodies, such as magnets, is a potentially lethal accident that affects children and is associated with bleeding and gastrointestinal perforation, as well as death. There are no Latin American reports in the literature on cases of magnet ingestion in children. Our aim was to establish whether said ingestion has been seen by pediatric endoscopists and gastroenterologists in Latin America, to determine the scope of that potential threat in their patient populations. MATERIALS AND METHODS: We collected data regarding endoscopies performed on children in Latin America, within the time frame of 2017-2019, through questionnaires that were distributed to pediatric endoscopists at the 2nd World Congress of Gastrointestinal Endoscopy (ENDO 2020). The questionnaires provided information on foreign body location, the presence and number of ingested magnets, and the description of complications and surgical interventions. RESULTS: Our cohort from 12 Latin American countries reported 2,363 endoscopies due to foreign body ingestion, 25 (1.05%) of which were the result of having swallowed one or more magnets. Mean patient age was 5.14 years (SD 2.5) and 10 (40%) of the cases were girls. Three (12%) of the patients presented with severe complications and 2 (8%) cases required surgery. CONCLUSIONS: Our preliminary study suggests that the ingestion of magnets is not common in Latin American countries, but said cases are frequently associated with complications. Constant monitoring of the incidence of such cases is extremely important, so that through education and awareness of those events, life-threatening complications in children can be prevented.

Magnet ingestion knows no borders: A threat for Latin American children. / La ingestión de imanes no conoce fronteras: una amenaza para los niños latinoamericanos.

INTRODUCTION AND AIMS: The ingestion of foreign bodies, such as magnets, is a potentially lethal accident that affects children and is associated with bleeding and gastrointestinal perforation, as well as death. There are no Latin American reports in the literature on cases of magnet ingestion in children. Our aim was to establish whether said ingestion has been seen by pediatric endoscopists and gastroenterologists in Latin America, to determine the scope of that potential threat in their patient populations. MATERIALS AND METHODS: We collected data regarding endoscopies performed on children in Latin America, within the time frame of 2017-2019, through questionnaires that were distributed to pediatric endoscopists at the 2nd World Congress of Gastrointestinal Endoscopy (ENDO 2020). The questionnaires provided information on foreign body location, the presence and number of ingested magnets, and the description of complications and surgical interventions. RESULTS: Our cohort from 12 Latin American countries reported 2,363 endoscopies due to foreign body ingestion, 25 (1.05%) of which were the result of having swallowed one or more magnets. Mean patient age was 5.14years (SD2.5) and 10 (40%) of the cases were girls. Three (12%) of the patients presented with severe complications and 2 (8%) cases required surgery. CONCLUSIONS: Our preliminary study suggests that the ingestion of magnets is not common in Latin American countries, but said cases are frequently associated with complications. Constant monitoring of the incidence of such cases is extremely important, so that through education and awareness of those events, life-threatening complications in children can be prevented.

Probiotic Properties of Alcaligenes faecalis Isolated from Argyrosomus regius in Experimental Peritonitis (Rat Model).

A strain of Alcaligenes faecalis A12C (A. faecalis A12C) isolated from Argyrosomus regius is a probiotic in fish. Previous experiments showed that A. faecalis A12C had inhibitory effects on the growth of multidrug-resistant bacteria. We aimed to confirm whether A. faecalis A12C is safe and has adequate intestinal colonization in experimental rats, and evaluate its efficacy in an animal model of peritonitis. We used 30 male rats, randomly divided into 6 groups (n = 5): three groups (HA7, HA15, HA30) received A. faecalis A12C in drinking water (6 × 108 CFU/mL) for 7 days, and three control groups received drinking water only. All groups were evaluated at 7, 15, and 30 days. Survival after A. faecalis A12C administration was 100% in all groups. Mild eosinophilia (1.5%, p < 0.01) and increased aspartate aminotransferase (86 IU/L, p < 0.05) were observed in HA7, followed by progressive normalization. No histological signs of organ injury were found. We observed significant E. coli decline in faeces, parallel to an increase in A. faecalis A12C at 7 days. E. coli had a tendency to recover initial values, while A. faecalis A12C disappeared from the intestinal microbiota at 30 days. To evaluate its efficacy against peritonitis, we studied two additional groups of animals: IA group pretreated with A. faecalis A12C before E. coli intra-abdominal inoculation, and IC group inoculated with no A. faecalis A12C. We found an increase in C-reactive protein, alanine aminotransferase, urea, and eosinophils in IC animals when compared with IA. Peritonitis was more evident in IC than in IA animals. Our findings suggest that A. faecalis A12C altered clinically relevant parameters in sepsis and was associated with a lesser spread of infection.

A new set of molecular markers for the genotyping of Babesia bovis isolates.

Babesia bovis is a tick-borne apicomplexan pathogen that remains an important constraint for the development of cattle industries worldwide. The existence of different strains and subpopulations has long been described in this hemoparasite. However, few molecular markers have been reported for strain genotyping and characterization. Minisatellite sequences show high levels of variation and therefore provide excellent tools for both the genotyping and population genetic analysis. In this work we report a set of five molecular markers containing minisatellites that showed a variable degree of polymorphism in several American strains. We have used a bioinformatics approach to search for marker sequences contained in open reading frames. Five genes were chosen and primers were designed in conserved regions flanking the repeat region. Two of the genes were the previously described Bv80/Bb-1 and TRAP. The other three genes were named p200, Antigen 3 and Desmoyokin. Amplification by PCR, sequencing and comparative analysis of 11 strains from Argentina, Brazil, Uruguay, Mexico and USA determined that the tandem repeats varied in number and sequence among the isolates. Genome analysis of the five markers revealed that they were single copy and distributed across the four B. bovis chromosomes. When the new markers were analyzed in an experimental infection, absolute sequence conservation was found, indicating the stability of these markers during the course of infection. These markers were also stable during three syringe passages through calves. The application of this panel of molecular markers could provide new molecular tools for the genotyping of B. bovis isolates and analysis of changes in parasite populations following vaccination.

[Assessment of nutritional interventions and hygiene and health habits in a cohort of primary school students]. / Evaluación de dos intervenciones nutricionales y de hábitos de higiene y salud en una cohorte de alumnos de enseñanza primaria.

OBJECTIVE: To quantify by means of the so-called "Healthy lifestyle pyramid" and after two educational interventions, the changes in food intake, daily activities, and hygiene and health habits in the short and long terms in a cohort of healthy children. MATERIALS AND METHOD: prospective longitudinal study with baseline assessment of dietary and lifestyle habits, and two assessments after two educational interventions. RESULTS: 52 children participated, mean age 7.9 years, 15.4% of them being obese. There was a statistically significant reduction in whole milk intake in both the short and long term. There was a significant decrease in the short term in the intake of processed cold meat and an increase in fruit intake. There was a significant reduction in sweets intake in the short term. There was a statistically significant change in hand washing in the short and long terms, as well as in beach bathing after eating. There also was a significant change in achieving an appropriate posture and not bathing too far away, both in the long run. Finally, there was a significant change in the short term in not using inappropriate sports playing fields. The frequency at which they practise sports in the long term was significantly increased as well as the number of weekly sports, in the short term. CONCLUSIONS: After two educational interventions, the children did significant modifications of their health habits in the short term or the long term, which contributes to modify the risk factors for disease in the adulthood.

Advances in the development of molecular tools for the control of bovine babesiosis in Mexico.

The severe negative impact that bovine babesiosis has in the Mexican cattle industry has not been ameliorated basically due to the lack of safe and effective commercially available vaccines and sensitive and reliable diagnostic tests. In recent years, the Bovine Babesiosis Laboratory at the National Center for Disciplinary Research in Veterinary Parasitology-INIFAP in Morelos State, Mexico has been directing efforts towards three main research areas: (1) The development of in vitro culture-derived, improved and safer live vaccines. This has been done in two ways: using gamma-irradiated bovine serum and erythrocytes for the in vitro culture of vaccine strains, which reduces the risk of contaminating pathogens, and improving the immune response, by the addition of L. casei, a strong stimulant of the innate immune system. (2) The study of antigens considered as vaccine candidates with the goal of developing a recombinant vaccine that suits the country's needs. Knowing their degree of conservation or variation in Mexican isolates, their phylogenetic relationship and their protective, immuno-stimulatory properties, are first steps towards that goal. (3) The development of new tools for diagnosis, detection and discrimination of bovine babesiosis is the third area. Developing variants of ELISA, which are more reliable than the currently used IFAT, are a priority, and finally, taking advantage of the genomes of Babesia bigemina, and B. bovis, we are identifying genes than allow us to discriminate isolates using molecular tools.

Influence of Traditional Management and Environmental Variables on Mediterranean Saproxylic Beetle Assemblages.

Mediterranean oak forests of the Iberian Peninsula host a great diversity of saproxylic beetles. For centuries, humans have carried out traditional management practices in this area, at both habitat and tree level, causing changes in forest structure. The aim of this study was to evaluate the anthropic effect of these traditional practices on saproxylic beetle diversity by measuring a set of environmental variables related to forest structure at both plot and tree level. Fauna was collected using window traps over a period of 12 mo. Multiple regression procedures showed which variables significantly affected the diversity of the studied assemblage. Our results demonstrated that the different metrics used to assess the diversity of assemblages responded variably depending on the management strategies applied and the level at which they were carried out. Certain management practices that disrupted the landscape from its natural state, such as the introduction of livestock or the local removal of particular trees, maximized species richness but, nevertheless, had a negative effect on the rest of diversity metrics analyzed. However, other practices such as pollarding, which involves the suppression of the main branch of the tree, had a positive effect on all diversity metrics evaluated as it promoted the formation of potential microhabitats for saproxylic fauna. We concluded that not all types and degrees of traditional forest management favor saproxylic beetle diversity and that different diversity metrics should be taken into consideration in future strategies for the protection and conservation of this fauna.

Effects of laterodorsal tegmentum excitotoxic lesions on behavioral and dopamine responses evoked by morphine and d-amphetamine.

Cholinergic and glutamatergic projections from the laterodorsal tegmental nucleus (LDT) in the rat pons excite midbrain dopamine cells to directly modulate forebrain dopamine transmission. We show that LDT-lesioned rats express higher intensity stereotypy (including orofacial movements), and higher levels of accumbal dopamine release in response to d-amphetamine (1.5 mg/kg), as compared to sham-operated rats. In contrast, LDT-lesioned rats showed decreased stereotypy and attenuated accumbal dopamine efflux as compared to sham animals, in response to morphine (2.0 mg/kg). These results suggest that the LDT plays a critical role in mediating motoric and neurochemical effects of diverse drugs of abuse, and that the pharmacology of the drug may critically determine whether its efficacy will be enhanced or attenuated by alterations in LDT activity. We conclude that the LDT has functional connections with the nigrostriatal dopamine system to affect drug-evoked stereotypy, which has implications for motoric disorders that are characterized by nigrostriatal dysfunction.

Electrophysiological and hemolytic activity elicited by the venom of the jellyfish Cassiopea xamachana.

In this study, we determined hemolysis activity in human and sheep erythrocytes, and characterized the electrical responses in Xenopus oocyte membrane elicited by the venom of the jellyfish Cassiopea xamachana (Cx). The Cx venom produced hemolysis in both species, being more potent on human red cells. The electrophysiological study showed that the Cx venom elicited three different responses in the oocytes. One current was generated in all the oocytes tested and corresponded with a slow inward current (I(Cx)) associated with an increase in membrane conductance. I(Cx) was concentration-dependent and had a reversal potential of -10.3+/-0.4 mV. Ionic substitution studies indicated that the conductive pathway was mainly permeable to cations and non-selective. The oocyte membrane resistance was completely recovered after washout of the venom, this suggested that the effect was due to generation of a specific membrane conductance as opposed to a possible non-specific membrane breakdown. A comparative study with three distinct native cationic channels present in the oocyte membrane [i.e. (1) hemi-gap-junction channels, (2) mechanosensitive channels, and (3) the ouabain-sensitive channel activated by palytoxin], showed that I(Cx) might correspond to opening of mechanosensitive channels or to activation of an unknown cationic channel located in the oocyte membrane. The bioactive fraction eliciting I(Cx) were peptides and was separated from two other peptidic hemolytic fractions by chromatography.

Distribution of the AMPFLPs YNZ22, 3'Apob and COL2A1 in the population of Galicia (NW Spain).

Two different electrophoretic methods were used for typing three amplified fragment length polymorphisms (AMPFLPs), (3'ApoB, YNZ22 and COL2A1) in a Galician (NW Spain) population sample. Because of the problems of anomalous mobility for the 3'ApoB system and the intermediate alleles found in the COL2A1 system, the use of automated sequencers and denaturing conditions is recommended for typing these two systems. Nevertheless, simple electrophoretic methods, such as the PhastSystem, can be used for YNZ22 typing. Although intermediate COL2A1 alleles can be distinguished with the sequencers, a binning approach was adopted for comparison purposes. The population sampled was in Hardy-Weinberg equilibrium for the three systems using an exact test. This type of statistical analysis is more appropriate when the number of alleles in a system is high. No significant differences with other Caucasian populations were found for the three systems studied. The characteristics of the polymorphisms, shown by 3'ApoB, YNZ22 and COL2A1, reflected in the statistical parameters studied, demonstrate that these AMPFLPs are of considerable interest for forensic purposes.

Identification, by RT-PCR, of eight novel I2-conotoxins from the worm-hunting cone snails Conus brunneus, Conus nux, and Conus princeps from the eastern Pacific (Mexico).

Marine snails of the genus Conus (∼500 species) are tropical predators that produce venoms for capturing prey, defense and competitive interactions. These venoms contain 50-200 different peptides ("conotoxins") that generally comprise 7-40 amino acid residues (including 0-5 disulfide bridges), and that frequently contain diverse posttranslational modifications, some of which have been demonstrated to be important for folding, stability, and biological activity. Most conotoxins affect voltage- and ligand-gated ion channels, G protein-coupled receptors, and neurotransmitter transporters, generally with high affinity and specificity. Due to these features, several conotoxins are used as molecular tools, diagnostic agents, medicines, and models for drug design. Based on the signal sequence of their precursors, conotoxins have been classified into genetic superfamilies, whereas their molecular targets allow them to be classified into pharmacological families. The objective of this work was to identify and analyze partial cDNAs encoding precursors of conotoxins belonging to I superfamily from three vermivorous species of the Mexican Pacific coast: C. brunneus, C. nux and C. princeps. The precursors identified contain diverse numbers of amino acid residues (C. brunneus, 65 or 71; C. nux, 70; C. princeps, 72 or 73), and all include a highly conserved signal peptide, a C-terminal propeptide, and a mature toxin. All the latter have one of the typical Cys frameworks of the I-conotoxins (C-C-CC-CC-C-C). The prepropeptides belong to the I2-superfamily, and encode eight different hydrophilic and acidic mature toxins, rather similar among them, and some of which have similarity with I2-conotoxins targeting voltage- and voltage-and-calcium-gated potassium channels.

Evidence for protein-mediated fatty acid efflux by adipocytes.

AIM: The hormonally controlled mobilization and release of fatty acids from adipocytes into the circulation is an important physiological process required for energy homeostasis. While uptake of fatty acids by adipocytes has been suggested to be predominantly protein-mediated, it is unclear whether the efflux of fatty acids also requires membrane proteins. METHODS: We used fluorescent fatty acid efflux assays and colorimetric assays for free fatty acids and glycerol to identify inhibitors with effects on fatty acid efflux, but not lipolysis, in 3T3-L1 adipocytes. We assessed the effect of these inhibitors on a fibroblast-based cell line expressing fatty acid transport protein 1, hormone-sensitive lipase and perilipin, which presumably lacks adipocyte-specific proteins for fatty acid efflux. RESULTS: We identified 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) as an inhibitor of fatty acid efflux that did not impair lipolysis or the cellular exit of glycerol but lead to an accumulation of intracellular fatty acids. In contrast, fatty acid efflux by the reconstituted cellular model for fatty acid efflux was responsive to lipolytic stimuli, but insensitive to DIDS inhibition. CONCLUSION: We propose that adipocytes specifically express an as yet unidentified DIDS-sensitive protein that enhances the efflux of fatty acids and therefore may lead to novel treatment approaches for obesity-related disorders characterized by abnormal lipid fluxes and ectopic triglyceride accumulation.

Role of emerging respiratory viruses in children with severe acute wheezing.

BACKGROUND: Acute wheezing episodes are frequently associated with respiratory viral infections in children. However, the role of the recently described respiratory viruses is not yet fully understood. OBJECTIVE: The main objective of this study was to estimate the frequency of human metapneumovirus (HMPV), human bocavirus (HBoV), and 14 other respiratory viruses in hospitalized children with acute wheezing. METHODS: A prospective study was conducted on children <14 years old, admitted with an acute expiratory wheezing episode from September 2005 to June 2008. Viruses were detected in nasopharyngeal aspirates by polymerase chain reaction. Clinical data were prospectively recorded. RESULTS: A viral pathogen was identified in 444 (71%) out of 626 hospitalized acute wheezing episodes. Respiratory syncytial virus (RSV) was the most frequently detected (27%), followed by rhinovirus (24%), adenovirus (17.8%), HBoV (16%), and HMPV (4.7%). The rate of viral detection was significantly higher in infants (77.3%), than in older children (59.8%) (P < 0.001). RSV and HBoV were more prevalent in infants (P < 0.001) than in older children. CONCLUSION: The most prevalent viruses found in severe acute wheezing episodes were RSV and rhinovirus not only in childhood, but also in infancy. However, other emerging viruses such as HBoV and metapneumovirus also play an important role in wheezing episodes.

[Migraine with aura and patent foramen ovale. A different clinical entity]. / Migraña con aura y foramen oval permeable. Una entidad clínica diferente?

INTRODUCTION: This work has aimed to evaluate the prevalence of patent foramen ovale in subjects with migraine with aura by transcranial contrast doppler and to describe the clinical and risk profile of these patients. METHOD: We performed a transcranial contrast doppler in 94 consecutive out-patients with migraine with aura (MWA) in a neurology outpatient clinic. They were divided into two groups according to the presence of patent foramen ovale: MWA_RLsh (with right-to-left shunt) and MWA_RLNsh (without right-to-left shunt). Differences between the groups were analyzed according to endpoints of age, gender, clinical severity, aura type and attacks frequency, comorbility, cardiovascular risk factors (CVRFs), neuroimaging findings, severity of shunt and treatment. RESULTS: n=94; MWA_RLsh: 47 (54%). MWA_RLNsh: 40 (46%). Age: 33.13; standard desviation (SD): 10.8 vs 33.496; SD: 11.2; p=0.728. Female: 66 vs 72.5%; p=0.511. Visual aura: 73.9% vs 78.9%; p=0.921. There were no significant differences in regards to the risk factors studied or to the comorbid diseases that are associated to migraine. The patients with patent foramen ovale have an odds ratio (OR) of ischemic stroke: 1.189 (95% confidence interval [CI]: 0.226 to 6.248; p=0.840), OR for subclinical brain lesions in cranial magnetic resonance imaging (MRI): 0.589 (95% CI: 0.193 to 1.799; p=0.35) and OR for combined previous ischemic stroke and subclinical brain lesions: 0.745 (95% CI: 0.261 to 2.129; p=0.58). Migraine attack frequency >1 per month: 27.9 vs 36.4; p=0.464. Need for prophylaxis therapy: 44.7 vs 57.7%; p=0.284. CONCLUSIONS: Both groups are similar regarding their clinical profile. We did not find a greater prevalence of stroke or silent brain lesions in the group with positive shunt..

[Stroke in the very old. Care in neurology units versus others general medical ward]. / Ictus en pacientes muy mayores. Análisis comparativo entre una unidad de neurología y otros servicios de medicina.

INTRODUCTION: The aim of this study is to compare the diagnosis, management, clinical course and outcome of the very major patients with acute stroke in our sanitary area. METHOD: Retrospective collection of data from a hospital-based registry, between January 2002 and March 2004, 130 stroke patients aged 84 and older admitted consecutively. We compared the patients admitted to the neurology unit (NU) to those admitted to other services (GWs). Demographic analysis, risk factors, morbidity to hospital admission (dementia, cancer, previous stroke and laboratory variables), neurological deficit measured for Canadian Neurological Scale (CNS) score, diagnostic studies, length of stay, outcomes variables (in-hospital mortality, complications developed during hospitalization and Rankin scale at hospital discharge) and need for institutionalization were analyzed. RESULTS: from a total of 130 patients, 44 (34,1 %) admitted to NU and 85 (65,9 %) to GWs. No difference was seen in demographic analysis, risk factors, morbidity to hospital admission, neurological deficit and outcomes variables. Length of stay was 8,4 days; 5,5 in the NU and 12,87 days among patients in the GWs (p=0,0001). There are significant differences in diagnostic studies in favor to NU (p < 0,05). Among the patients admitted into GWs the percentage of institutionalization to the discharge was of 28,8 % opposite to 5,6 % in the NU (p=0,006). CONCLUSIONS: There are not evidences of age discrimination for access to neurological units for demographic, risk factors, morbidity or neurological deficit. The diagnostic process is more rigorous and less costly in the NU than in the GWs.

The neutrophilic and fibrinolytic response to talc can predict the outcome of pleurodesis.

It was hypothesised that monitoring neutrophil and D-dimer (DD) levels into the pleural fluid, after talc instillation, could predict the outcome of pleurodesis. The current authors investigated a total of 168 patients with malignant pleural effusion, who were treated with talc poudrage. According to the outcome the patients were categorised into one of two groups, either successful or failed pleurodesis. In all cases, pleural fluid neutrophils and DDs were determined on serial measurements at 0, 3, 24 and 48 h after the procedure. The time course of these parameters was assessed in both groups and the time point at which they could better predict the outcome was further explored. Neutrophils rose rapidly after talc poudrage in both groups, reaching a plateau at 24 h, although in successful pleurodesis this response was significantly higher. DD dropped markedly at 24 h in the group with the successful outcome, but it did not show significant changes in the other group. A cut-off value of 61% for neutrophils and 61 mg.L-1 for the DD at 24 h yielded the best prognosis for successful pleurodesis. The current authors conclude that serial measurements of neutrophil and d-dimer values into the pleural fluid after talc poudrage could be used as predictors of the outcome of pleurodesis.

Interaction of influenza virus NS1 protein and the human homologue of Staufen in vivo and in vitro.

A screening for human proteins capable of interacting with influenza virus NS1 has been carried out using the two-hybrid genetic trap in yeast. A cDNA corresponding to the human homologue of Drosophila melanogaster Staufen protein (hStaufen) was isolated that fulfilled all genetic controls of the two-hybrid protocol. Using a hStaufen cDNA isolated from a lambda human library, the interaction of hStaufen and NS1 proteins was characterised in vivo and in vitro. Co-transfection of NS1 cDNA and a partial cDNA of hStaufen led to the relocalisation of recombinant hStaufen protein from its normal accumulation site in the cytoplasm to the nuclear location of NS1 protein. NS1 and hStaufen proteins could be co-immunoprecipitated from extracts of co-transfected cells and from mixtures of extracts containing either protein, as well as from extracts of influenza virus-infected cells. Furthermore, both proteins co-localised in the ribosomal and polysomal fractions of influenza virus-infected cells. The interaction was also detected in pull-down experiments using a resin containing purified hStaufen and NS1 protein translated in vitro. Deletion mapping of the NS1 gene indicated that a mutant protein containing the N-terminal 81 amino acids is unable to interact with hStaufen, in spite of retaining full RNA-binding capacity. These results are discussed in relation to the possible mechanisms of action of hStaufen and its relevance for influenza virus infection.

[Poisoning by enterotoxin from Staphylococcus aureus associated with mocha pastry. Microbiology and epidemiology]. / Intoxicación por enterotoxina de Staphylococcus aureus asociado al consumo de pastel de moka. Microbiología y epidemiología.

A brief description of a foodborne outbreak due to S. aureus enterotoxin associated with the consumption of mocha cake in the city of Guadalajara is presented. The cake was prepared in a bakery and affected nearly 100 persons. S. aureus was isolated from the nose and skin of one of the pastry cooks. A S. aureus strain isolated from the cake involved in the outbreak was not only unable to grow in the mocha cream, but it actually decreased in numbers by 2 log after 72 h of storage at 30 degrees C. The pH of mocha cream ranged from 6.2 to 6.6, and water activity from 0.833 to 0.859, with a media of 0.841. In preparing mocha cake at the shop, one half of the dough used to be sprayed with a sucrose solution in water (20% w/v); mocha cream was spread on the other half of the dough before overlapping the two halves. When mocha cake was prepared in this manner, and stored at 30 degrees C, S. aureus increased in number by more than 4 log after 48 h. S. aureus did not grow in the cake stored at 4-7 degrees C. Contributory factors in this outbreak were an increase of water activity in the interphase of the mocha and the cake dough, storage of the cake in an unrefrigerated area, and an unusually high ambient temperature (28-32 degrees C) at that time.