The MqsRA toxin-antitoxin system from xylella fastidiosa plays a key role in bacterial fitness, pathogenicity, and persister cell formation

Through the formation of persister cells, bacteria exhibit tolerance to multidrug and other environmental stresses without undergoing genetic changes. The toxin-antitoxin (TA) systems are involved in the formation of persister cells because they are able to induce cell dormancy. Among the TA systems, the MqsRA system has been observed to be highly induced in persister cells of Xylella fastidiosa (causal agent of citrus variegated chlorosis-CVC) activated by copper stress, and has been described in Escherichia coil as related to the formation of persister cells and biofilms. Thus, we evaluated the role of this TA system in X. fastidiosa by overexpressing the MqsR toxin, and verified that the toxin positively regulated biofilm formation and negatively cell movement, resulting in reduced pathogenicity in citrus plants. The overexpression of MqsR also increased the formation of persister cells under copper stress. Analysis of the gene and protein expression showed that this system likely has an autoregulation mechanism to express the toxin and antitoxin in the most beneficial ratio for the cell to oppose stress. Our results suggest that this TA system plays a key role in the adaptation and survival of X fastidiosa and reveal new insights into the physiology of phytopathogen host interactions7CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão tem2010/50712-9; 2013/17485-7; 2013/02014-

Analysis of the biofilm proteome of Xylella fastidiosa

<p>Abstract</p> <p>Background</p> <p><it>Xylella fastidiosa </it>is limited to the xylem of the plant host and the foregut of insect vectors (sharpshooters). The mechanism of pathogenicity of this bacterium differs from other plant pathogens, since it does not present typical genes that confer specific interactions between plant and pathogens (avr and/or hrp). The bacterium is injected directly into the xylem vessels where it adheres and colonizes. The whole process leads to the formation of biofilms, which are considered the main mechanism of pathogenicity. Cells in biofilms are metabolically and phenotypically different from their planktonic condition. The mature biofilm stage (phase of higher cell density) presents high virulence and resistance to toxic substances such as antibiotics and detergents. Here we performed proteomic analysis of proteins expressed exclusively in the mature biofilm of <it>X. fastidiosa </it>strain 9a5c, in comparison to planktonic growth condition.</p> <p>Results</p> <p>We found a total of 456 proteins expressed in the biofilm condition, which correspond to approximately 10% of total protein in the genome. The biofilm showed 37% (or 144 proteins) different protein than we found in the planktonic growth condition. The large difference in protein pattern in the biofilm condition may be responsible for the physiological changes of the cells in the biofilm of <it>X. fastidiosa</it>. Mass spectrometry was used to identify these proteins, while real-time quantitative polymerase chain reaction monitored expression of genes encoding them. Most of proteins expressed in the mature biofilm growth were associated with metabolism, adhesion, pathogenicity and stress conditions. Even though the biofilm cells in this work were not submitted to any stress condition, some stress related proteins were expressed only in the biofilm condition, suggesting that the biofilm cells would constitutively express proteins in different adverse environments.</p> <p>Conclusions</p> <p>We observed overexpression of proteins related to quorum sensing, proving the existence of communication between cells, and thus the development of structuring the biofilm (mature biofilm) leading to obstruction of vessels and development of disease. This paper reports a first proteomic analysis of mature biofilm of <it>X. fastidiosa</it>, opening new perspectives for understanding the biochemistry of mature biofilm growth in a plant pathogen.</p

Information Design and the COVID-19 pandemic: What is the contribution to health and citizenship?

Multiple and various graphic design pieces were created around the world for digital media during the COVID-19 pandemic. These graphic design pieces were meant to disseminate information about the disease caused by the new Corona Virus SARS-CoV-2 to inform people on how to better protect themselves. Information Design uses guidelines and principles that would inform the design of useful graphic pieces to combat the pandemic and help the people to address their health needs for citizenship rights. This research analyzed multiple pieces made available by Fiocruz (a Brazilian health institution). The case study presented in this paper explores the piece with information explaining how soap acts on the virus and proposes a new design to improve its quality

Efeito do uso de leite fortificado com ferro e vitamina C sobre os níveis de hemoglobina e condição nutricional de crianças menores de 2 anos

The impact of the use of fortified powdered whole milk (9 mg of iron and 65 mg of vitamin C/100 g of milk) on the hemoglobin levels of children under 2 years of age was evaluated, over a period of 6 months, in 107 children enrolled in municipal Day Care Centers (DCC) and in 228 seen at a Basic Health Care Unit (BHCU). Before the beginning of the intervention 66.4% of the children in the DCC and 72.8% of those seen at the BHCU had hemoglobin levels ender 11.0 g/dl. After 6 months of fortified milk intake, these percentages fell to 20.6% and 18.0% respectively. the average hemoglobin before the intervention was 10.3 g/dl in the DCC and 10.5 in the BHCU. After 6 months these increased to 11.6 g/dl in the populations studied. Concerning the nutritional condition, evaluated according to Gomez's criteria, 57% of the DCC children presented an improvement, 41.1% showed changens and only 1.9% became worse. in the BHCU, 11.4% presented better condition, 70.6% remained the same and 18% worsened, which demonstrated differences in response regarding improvement of nutritional condition, when fortified milk was used in closed and open environments. the authors conclude that the utilization of enriched foods is an excellent alternative in the treatment of iron deficiency in populations of children under 2 years of age.Universidade Federal de São Paulo,DEPT PREVENT MED,São Paulo,BRAZILFAC MED BOTUCATU,DEPT PEDIAT,BOTUCATU,BRAZILUniversidade Federal de São Paulo,DEPT PREVENT MED,São Paulo,BRAZILWeb of Scienc

Estudo prévio de uma unidade industrial para produção de vinagrete sólido

Este trabalho consiste num estudo prévio tendo em vista o projeto de uma unidade industrial para a produção de vinagrete sólido. O produto em causa, o vinagrete sólido, assume-se como inovador, colocando-se como uma alternativa fácil para o tempero de saladas e potenciando novos sabores agradáveis ao paladar que cativem o consumidor. O trabalho inclui o estudo do processo, com descrição das etapas de preparação, os balanços mássicos, a descrição das peças de equipamento, a implantação fabril e uma breve estimativa do investimento necessário

Early colonization pattern of maize (Zea mays L. Poales, Poaceae) roots by Herbaspirillum seropedicae (Burkholderiales, Oxalobacteraceae)

The bacterium Herbaspirillum seropedicae is an endophytic diazotroph found in several plants, including economically important poaceous species. However, the mechanisms involved in the interaction between H. seropedicae and these plants are not completely characterized. We investigated the attachment of Herbaspirillum to maize roots and the invasion of the roots by this bacterium using H. seropedicae strain SMR1 transformed with the suicide plasmid pUTKandsRed, which carries a mini-Tn5 transposon containing the gene for the Discosoma red fluorescent protein (Dsred) constitutively expressed together with the kanamycin resistance gene. Integration of the mini-Tn5 into the bacterial chromosome yielded the mutant H. seropedicae strain RAM4 which was capable of expressing Dsred and could be observed on and inside fresh maize root samples. Confocal microscopy of maize roots inoculated with H. seropedicae three days after germination showed that H. seropedicae cell were attached to the root surface 30 min after inoculation, were visible in the internal tissues after twenty-four hours and in the endodermis, the central cylinder and xylem after three days

Efeito do uso de leite fortificado com ferro e vitamina C sobre os níveis de hemoglobina e condição nutricional de crianças menores de 2 anos

The impact of the use of fortified powdered whole milk (9 mg of iron and 65 mg of vitamin C/100 g of milk) on the hemoglobin levels of children under 2 years of age was evaluated, overa period of 6 months, in 107 children enrolled in municipal Day Care Centers (DCC) and in 228 seen at a Basic Health Care Unit (BHCU). Before the beginning of the intervention, 66.4% of the children in the DCC and 72.8% of those seen at the BHCU had hemoglobin levels under 11.0g/dl. After 6 months of fortified milk intake, these percentages fell to 20.6% and 18.0% respectively. The average hemoglobin before the intervention was 10.3 g/dl in the DCC and 10.5 in the BHCU. After 6 months these increased to 11.6g/dl in the populations studied. Concerning the nutritional condition, evaluated according to Gomez's criteria, 57% of the DCC children presented an improvement, 41.1% showed changens and only 1.9% became worse. In the BHCU, 11.4% presented better condition, 70.6% remained the same and 18% worsened, which demonstrated differences in response regarding improvement of nutritional condition, when fortified milk was used in closed and open environments. The authors conclude that the utilization of enriched foods is an excellent alternative in the treatment of iron deficiency in populations of children under 2 years of age.Foi avaliado o impacto do uso do leite em pó integral fortificado com 9 mg de ferro e 65 mg de vitamina C para cada 100 g de pó, sobre os níveis de hemoglobina de crianças menores de 2 anos, em 107 crianças de creches municipais e 228 de uma Unidade Básica de Saúde (UBS), por um período de 6 meses. Antes de se iniciar a intervenção, 66,4% das crianças das creches e 72,8% da UBS apresentavam níveis de hemoglobina inferiores a 11,0 g/dl. Ao final dos 6 meses de uso do leite fortificado, esses percentuais reduziram-se para 20,6% nas creches e 18,0% na UBS. A média da hemoglobina, antes de se iniciar o experimento, foi de 10,3 g/dl nas creches e 10,5 g/dl na UBS. Decorridos 6 meses esses valores subiram para 11,6 g/dl nas duas populações estudadas. Em relação à condição nutricional, avaliada pelo critério de Gomez, verificou-se que, nas creches, 57% das crianças acompanhadas apresentaram melhoria na sua condição nutricional, 41,1% ficaram inalteradas e apenas 1,9% pioraram. Na UBS, 11,4% apresentaram melhora, 70,6% ficaram inalteradas e 18% pioraram, o que mostrou uma diferença de resposta quanto à recuperação da condição nutricional, quando o leite enriquecido foi utilizado em ambiente aberto e fechado. Concluiu-se que a utilização de alimentos fortificados apresenta-se como excelente alternativa para o controle da carência de ferro em populações de crianças menores de 2 anos

Anomalous weak values via a single photon detection

open10Is it possible that a measurement of a spin component of a spin-1/2 particle yields the value 100? In 1988 Aharonov, Albert and Vaidman argued that upon pre- and postselection of particular spin states, weakening the coupling of a standard measurement procedure ensures this paradoxical result(1). This theoretical prediction, called weak value, was realised in numerous experiments(2-9), but its meaning remains very controversial(10-19), since its "anomalous" nature, i.e., the possibility to exceed the eigenvalue spectrum, as well as its "quantumness" are debated(20-22). We address these questions by presenting the first experiment measuring anomalous weak values with just a single click, without the need for statistical averaging. The measurement uncertainty is significantly smaller than the gap between the measured weak value and the nearest eigenvalue. Beyond clarifying the meaning of weak values, demonstrating their non-statistical, single-particle nature, this result represents a breakthrough in understanding the foundations of quantum measurement, showing unprecedented measurement capability for further applications of weak values to quantum photonics.openRebufello, E; Piacentini, F; Avella, A; de Souza, MA; Gramegna, M; Dziewior, J; Cohen, E; Vaidman, L; Degiovanni, IP; Genovese, MRebufello, E; Piacentini, F; Avella, A; de Souza, Ma; Gramegna, M; Dziewior, J; Cohen, E; Vaidman, L; Degiovanni, Ip; Genovese,

Fasceite eosinofílica simulando esclerose lateral amiotrófica

Federal University of São Paulo Department of Neurology and Neurosurgery Neuromuscular Disorders UnitHospital São CristovãoUNIFESP, Department of Neurology and Neurosurgery Neuromuscular Disorders UnitSciEL