The asymptomatic bacteriuria Escherichia coli strain 83972 outcompetes uropathogenic E-coli strains in human urine

Escherichia coli is the most common organism associated with asymptomatic bacteriuria (ABU). In contrast to uropathogenic E. coli (UPEC), which causes symptomatic urinary tract infections (UTI), very little is known about the mechanisms by which these strains colonize the human urinary tract. The prototype ABU E. coli strain 83972 was originally isolated from a girl who had carried it asymptomatically for 3 years. Deliberate colonization of UTI-susceptible individuals with E. coli 83972 has been used successfully as an alternative approach for the treatment of patients who are refractory to conventional therapy. Colonization with strain 83972 appears to prevent infection with UPEC strains in such patients despite the fact that this strain is unable to express the primary adhesins involved in UTI, viz. P and type 1 fimbriae. Here we investigated the growth characteristics of E. coli 83972 in human urine and show that it can outcompete a representative spectrum of UPEC strains for growth in urine. The unique ability of ABU E. coli 83972 to outcompete UPEC in urine was also demonstrated in a murine model of human UTI, confirming the selective advantage over UPEC in vivo. Comparison of global gene expression profiles of E. coli 83972 grown in lab medium and human urine revealed significant differences in expression levels in the two media; significant down-regulation of genes encoding virulence factors such as hemolysin, lipid A, and capsular pollysaccharides was observed in cells grown in urine. Clearly, divergent abilities of ABU E. coli and UPEC to exploit human urine as a niche for persistence and survival suggest that these key differences may be exploited for preventative and/or therapeutic approaches.

Heart rate variability characterization using a time-frequency based instantaneous frequency estimation technique

In this paper, a new method for characterizing the newborn heart rate variability (HRV) is proposed. The central of the method is the newly proposed technique for instantaneous frequency (IF) estimation specifically designed for nonstationary multicomponen signals such as HRV. The new method attempts to characterize the newborn HRV using features extracted from the time–frequency (TF) domain of the signal. These features comprise the IF, the instantaneous bandwidth (IB) and instantaneous energy (IE) of the different TF components of the HRV. Applied to the HRV of both normal and seizure suffering newborns, this method clearly reveals the locations of the spectral peaks and their time-varying nature. The total energy of HRV components, ET and ratio of energy concentrated in the low-frequency (LF) to that in high frequency (HF) components have been shown to be significant features in identifying the HRV of newborn with seizures.

CONVERSÃO AO ISLÃ: UMA ANÁLISE SOCIOLÓGICA DA ASSIMILAÇÃO DO ETHOS RELIGIOSO NA SOCIEDADE MUÇULMANA SUNITA EM SÃO BERNARDO DO CAMPO NA REGIÃO DO GRANDE ABC

Esta dissertação tem por finalidade analisar o fenômeno religioso da conversão ao Islã. Com base em um estudo empírico a dissertação estuda a conversão ao Islã como sendo um processo de assimilação do ethos religioso islâmico empreendido por brasileiros de ascendência não árabe. Numa proposta sociológica o conceito de conversão foi ampliado e articulado junto aos conceitos de identidade e assimilação. Os convertidos entrevistados fazem parte de uma sociedade religiosa muçulmana sunita situada em São Bernardo do Campo na região do grande ABC, São Paulo, organizada em torno de um Centro de Divulgação do Islã para a América Latina (CDIAL), e de uma mesquita que leva o nome de Abu Bakr Assedic. Esta dissertação tenta compreender os antecedentes sócio-religiosos, os motivos da conversão e suas conseqüências. Para tanto, sustentamos ainda que o processo de conversão ao Islã é gradativo e empreendido por um sujeito ativo, que ao interpretar suas próprias experiências, constrói uma identidade particular e diferenciadora do ethos árabe.(AU)

Active membrane transport and receptor proteins from bacteria

A general strategy for the expression of bacterial membrane transport and receptor genes in Escherichia coli is described. Expression is amplified so that the encoded proteins comprise 5-35% of E. coli inner membrane protein. Depending upon their topology, proteins are produced with RGSH6 or a Strep tag at the C-terminus. These enable purification in mg quantities for crystallization and NMR studies. Examples of one nutrient uptake and one multidrug extrusion protein from Helicobacter pylori are described. This strategy is successful for membrane proteins from H. pylori, E. coli, Enterococcus faecalis, Bacillus subtilis, Staphylococcus aureus, Microbacterium liquefaciens, Brucella abortus, Brucella melitensis, Campylobacter jejuni, Neisseria meningitides, Streptomyces coelicolor and Rhodobacter sphaeroides. ©2005 Biochemical Society.

Controlling contractual discretion

In 1993 Leggatt L.J. said in Abu Dhabi National Tanker Co. v. Product Star Shipping Ltd. (The Product Star) [1993] 1 Lloyds Rep. 397, 404: Where A and B contract with each other to confer a discretion on A, that does not render B subject to A’s uninhibited whim. In my judgment, the authorities show that not only must the discretion be exercised honestly and in good faith, but, having regard to the provisions of the contract by which it is conferred, it must not be exercised arbitrarily, capriciously or unreasonably.

Advanced liquid-liquid extraction : studies in a laboratory mixer-settler

A ten stage laboratory mixer-settler has been designed, constructed and operated with efficiencies up to 90%. The phase equilibrium data of the system acetic acid-toluene-water at different temperatures has been determined and correlated. Trials for prediction of these data have been investigated and a good agreement between the experimental data and the predictions obtained by the NRTL equation have been found. Extraction processes have been analysed. A model for determination of the time needed for a countercurrent stage-wise process to come to steady state has been derived. The experimental data was in reasonable agreement with this model. The discrete maximum principle has been applied to optimize the countercurrent extraction process and proved to be highly successful in predicting the optimum operating conditions which were confirmed by the experimental results. The temperature has proved to be a prosolvent for mass transfer in both directions but the temperature profile functioned as an anti solvent.