Surto alimentar por Salmonella Enteritidis no Noroeste do Estado de São Paulo, Brasil

A foodborne outbreak which affected 211 persons occurred, in a School, in 1993. The epidemiological data obtained by interviewing the affected and non affected persons sampled showed as predominant symptoms: diarrhoea, fever (77.7%), abdominal cramps (67.7%), vomiting (65.8%), hot-and-cold sensations (54.5%) and headache (44.5%). The median incubation period was of 17 hours, the limits being 3 and 29 hours. The disease period was of from 3 to 4 days. The food concerned was a kind of paté, a mayonnaise mixture prepared with fresh eggs with boiled potatoes that was consumed with bread. The biological material analysis - 3 coprocultures, and leftovers of the food revealed the presence of one and the same organism: Salmonella Enteritidis. In the food, the numbers of this bacterium per gram were sufficient to account for the manifestation of the disease (104 and 105/g). The antibiogram of all the isolates showed the same sensibility pattern. The preparation related to this outbreak suggests the endogenous contamination of the eggs; the cross contamination - the outbreak affected three school periods, as the food was prepared separately for each school period; and the conditions under which the food was kept during the time from preparation to consumption. The observation of the 3 food handlers, by successive coprocultures, for one week, indicates that they were not asymptomatic carriers nor were they affected as a result of this outbreak by the causal bacteria.Em 1993 ocorreu um surto alimentar em escola, com 211 afetados. Os dados epidemiológicos levantados por entrevista de amostragem de afetados e não afetados mostraram que os sintomas predominantes foram diarréia, febre (77,7%), dor abdominal (67,7%), vômito (65,8%), calafrios (54,5%) e cefaléia (44,5%). A mediana de incubação foi de 17 horas, com limites entre 3 e 29 horas. A duração da doença foi de 3 a 4 dias. O alimento consumido foi um tipo de patê, mistura de molho de maionese preparada com ovos crus com batata cozida, passado em pão. A análise de material biológico (3 coproculturas) e de restos de alimentos revelou a presença do mesmo microrganismo, a Salmonella Enteritidis. No caso dos alimentos, o número encontrado desta bactéria por gramo de produto era compatível com a quantidade de células necessária para desencadear a doença (10(4)e 10(5)/g). O antibiograma de todas as cepas isoladas revelou o mesmo padrão de sensibilidade. As falhas no preparo do alimento relacionadas com o levantamento indicam a possibilidade de contaminação endógena dos ovos; contaminação cruzada - o surto afetou três períodos escolares, sendo que para cada um o alimento foi preparado em separado - e as condições de manutenção do alimento após preparo e até o consumo. A observação por uma semana seguida das 3 merendeiras envolvidas, através de coprocultura, não indicaram que as mesmas fossem portadoras assintomáticas desta bactéria ou que tivessem sido envolvidas no surto em questão

Measurements of differential production cross sections for a Z boson in association with jets in pp collisions at root s=8 TeV

Peer reviewe

Charged-particle nuclear modification factors in PbPb and pPb collisions at √=sNN=5.02 TeV

The spectra of charged particles produced within the pseudorapidity window |η| < 1 at √ sNN = 5.02 TeV are measured using 404 µb −1 of PbPb and 27.4 pb−1 of pp data collected by the CMS detector at the LHC in 2015. The spectra are presented over the transverse momentum ranges spanning 0.5 < pT < 400 GeV in pp and 0.7 < pT < 400 GeV in PbPb collisions. The corresponding nuclear modification factor, RAA, is measured in bins of collision centrality. The RAA in the 5% most central collisions shows a maximal suppression by a factor of 7–8 in the pT region of 6–9 GeV. This dip is followed by an increase, which continues up to the highest pT measured, and approaches unity in the vicinity of pT = 200 GeV. The RAA is compared to theoretical predictions and earlier experimental results at lower collision energies. The newly measured pp spectrum is combined with the pPb spectrum previously published by the CMS collaboration to construct the pPb nuclear modification factor, RpA, up to 120 GeV. For pT > 20 GeV, RpA exhibits weak momentum dependence and shows a moderate enhancement above unity

Pollen analysis, physico-chemical properties and antibacterial action of Brazilian honeys from Africanized honeybees (Apis mellifera L) and stingless bees

Two groups of Brazilian honeys were analyzed : - from Africanized honeybees (20 samples; = G1); - from stingless bees (14 samples; = G2). In the palynological studies, the pollen grains were identified by comparing them with a reference catalogue at the University of São Paulo bee laboratory of the USP. The acetolysis method was used to facilitate observations. In G1 the most active honeys against bacteria were those where Mimosa and Eucalyptus pollen was predominant. In G2, a honey produced by Plebeia sp with Borreria/Mimosa pollen and another by Melipona subnitida with Mimosa bimucronata pollen, were found to be most active against bacteria. There was less moisture and free acidity in the Apis honeys whereas the pH was lower in the honeys from stingless bees. Moisture was the characteristic which best differentiated the two groups (table IV). In colour, both ranged between amber and light-amber. All honeys were assayed against 7 strains of bacteria (tables V et VI). The honey was mixed in a concentration of 5-25% with agar and put on a plate; drops of bacterium culture were then spread inside this solid culture. After 24 h at 37°C a 1-5 grading was given to the honey tested, depending on the bacterial growth. Honeys from stingless bees had a stronger inhibition capacity than Apis honeys but this varied according to the species of stingless bee. The honeys from Apis showed inhibition with an average concentration of 15%, whereas in honeys from stingless bees the average inhibitory concentration was 11%. The minimum concentrations were 12.5% and 5.5% respectively. For both groups the least resistant bacterium was Bacillus stearothermophilus (Bst) and the most resistant Escherichia coli (Ec) (fig 2). Both groups of honeys were mainly bacteriostatic, ie in spite of sometimes damaging the bacteria they inhibited but did not kill them (Gram test). Honeys from the tribe Trigonini were found to be better antibacterial agents than those from Meliponini