Cellular variability of RpoS expression underlies subpopulation activation of an integrative and conjugative element.

Conjugative transfer of the integrative and conjugative element ICEclc in the bacterium Pseudomonas knackmussii is the consequence of a bistable decision taken in some 3% of cells in a population during stationary phase. Here we study the possible control exerted by the stationary phase sigma factor RpoS on the bistability decision. The gene for RpoS in P. knackmussii B13 was characterized, and a loss-of-function mutant was produced and complemented. We found that, in absence of RpoS, ICEclc transfer rates and activation of two key ICEclc promoters (P(int) and P(inR)) decrease significantly in cells during stationary phase. Microarray and gene reporter analysis indicated that the most direct effect of RpoS is on P(inR), whereas one of the gene products from the P(inR)-controlled operon (InrR) transmits activation to P(int) and other ICEclc core genes. Addition of a second rpoS copy under control of its native promoter resulted in an increase of the proportion of cells expressing the P(int) and P(inR) promoters to 18%. Strains in which rpoS was replaced by an rpoS-mcherry fusion showed high mCherry fluorescence of individual cells that had activated P(int) and P(inR), whereas a double-copy rpoS-mcherry-containing strain displayed twice as much mCherry fluorescence. This suggested that high RpoS levels are a prerequisite for an individual cell to activate P(inR) and thus ICEclc transfer. Double promoter-reporter fusions confirmed that expression of P(inR) is dominated by extrinsic noise, such as being the result of cellular variability in RpoS. In contrast, expression from P(int) is dominated by intrinsic noise, indicating it is specific to the ICEclc transmission cascade. Our results demonstrate how stochastic noise levels of global transcription factors can be transduced to a precise signaling cascade in a subpopulation of cells leading to ICE activation.

Framework for Corporate and Financial Governance for Agencies funded by the Department of Health and Children

Corporate governance is the system by which organisations direct and control their functions and relate to their stakeholders in order to manage their business, achieve their mission and objectives and meet the necessary standards of accountability, integrity and propriety. It is a key element in improving efficiency and accountability as well as enhancing openness and transparency. A significant element of the Governmentâ?Ts programme for health service reform is the strengthening of governance and accountability arrangements across the health system. Read the Report (PDF, 1mb)

Fonctions du plancher pelvien: de la phase expulsive à la consultation du post-partum [Pelvic floor functions: from the beginning of the second phase of labor to the postpartum consultation].

Vaginal delivery can cause lesions of the various pelvic structures responsible for the mechanisms of continence. These lesions may perhaps be prevented in the future by measuring pressure generated during childbirth. Tear of the anal sphincter during childbirth is a marker of a global impairment of the urinary, ano-rectal and sexual pelvic functions in the short and medium term. Persistence of a defect of the anal sphincter is frequent in spite of immediate suture. The correlation between these defects and ano-rectal incontinence are not established in our experience. The quality of the contraction of the sphincter complex and pubo-rectal sling seems to play a more important role in ano-rectal continence after a traumatic childbirth.

Production of recombinant TRAIL and TRAIL receptor: Fc chimeric proteins.

The tumor necrosis factor (TNF)/TNF receptor (TNFR) families of ligands and receptors are implicated in a variety of physiological and pathological processes and regulate cellular functions as diverse as proliferation, differentiation, and death. Recombinant forms of these ligands and receptors can act to agonize or antagonize these functions and are therefore useful for laboratory studies and may have clinical applications. A protocol is presented for the expression and purification of dimeric soluble receptors fused to the Fc portion of human IgG1 and of soluble, N-terminally Flag-tagged ligands. Soluble recombinant proteins are easier to handle than membrane-bound proteins and the use of tags greatly facilitates their detection and purification. In addition, some tags may provide enhanced biological activity to the recombinant proteins (mainly by oligomerization and stabilization effects) and facilitate their functional characterization. Expression in bacterial (for selected ligands) and eukaryotic expression systems (for ligands and receptors) was performed using M15 pREP4 bacteria and human embryonic kidney 293 cells, respectively. The yield of purified protein is about 1 mg/liter for the mammalian expression system and several milligrams per liter for the bacterial expression system. Protocols are given for a specific ligand-receptor pair, namely TRAIL (Apo-2L) and TRAIL receptor 2 (DR5), but can be applied to other ligands and receptors of the TNF family.

L'hémisphérotomie péri-insulaire: technique chirurgicale, monitoring EEG intraopératoire et résultats sur le contrôle de l'épilepsie [Periinsular hemispherotomy: surgical technique, intraoperative EEG monitoring and results on seizure outcome]

Peri-insular hemispherotomy is a surgical technique used in the treatment of drug-resistant epilepsy of hemispheric origin. It is based on the exposure of insula and semi-circular sulci, providing access to the lateral ventricle through a supra- and infra-insular window. From inside the ventricle, a parasagittal callosotomy is performed. The basal and medial portion of the frontal lobe is isolated. Projections to the anterior commissure are interrupted at the time of amygdala resection. The hippocampal tail and fimbria-fornix are disrupted posteriorly. We report our experience of 18 cases treated with this approach. More than half of them presented with congenital epilepsy. Neuronavigation was useful in precisely determining the center and extent of the craniotomy, as well as the direction of tractotomies and callosotomy, allowing minimal exposure and blood loss. Intra-operative monitoring by scalp EEG on the contralateral hemisphere was used to follow the progression of the number of interictal spikes during the disconnection procedure. Approximately 90% of patients were in Engel's Class I. We observed one case who presented with transient postoperative neurological deterioration probably due to CSF overdrainage and documented one case of incomplete disconnection in a patient presenting with hemimegalencephaly who needed a second operation. We observed a good correlation between a significant decrease in the number of spikes at the end of the procedure and seizure outcome. Peri-insular hemispherotomy provides a functional disconnection of the hemisphere with minimal resection of cerebral tissue. It is an efficient technique with a low complication rate. Intra-operative EEG monitoring might be used as a predictive factor of completeness of the disconnection and consequently, seizure outcome.

Acute acquired toxoplasmosis: clinical-laboratorial aspects and ophthalmologic evaluation in a cohort of immunocompetent patients

Most cases of acute acquired toxoplasmosis (AAT) are oligosymptomatic and self-limited. Therefore, these infections rarely indicate treatment. Prospective studies of AAT patients are rare in the medical literature. The frequency of systemic manifestations has not been sufficiently studied. In order to search for risks factors for systemic and ocular involvement, 37 patients were submitted to a diagnostic investigative protocol. The most frequent findings were lymph node enlargement (94.6%), asthenia (86.5%), headache (70.3%), fever (67.6%) and weight loss (62.2%). Hepatomegaly and/or splenomegaly were present in 21.6% of cases (8/37). Liver transaminases were elevated in 11 patients (29.7%) and lactic dehydrogenase in 17 patients (45.9%). Anaemia was found in four patients (10.8%), leucopoenia in six patients (16.2%), lymphocytosis in 14 patients (37.8%) and thrombocytopenia in one patient (2.7%). Fundoscopic examination revealed retinochoroiditis in four patients (10.8%). No statistical association was found between any one morbidity and retinochoroiditis. Nevertheless, a significant association was found between the presence of more than eight morbidity features at evaluation and long-lasting disease. An ideal diagnostic protocol for AAT would include evidence of systemic involvement. Such a protocol could be used when planning treatment.

F+0 renography in neonates and infants younger than 6 months: an accurate method to diagnose severe obstructive uropathy.

We studied the response to F+0 renography and the relative and absolute individual kidney function in neonates and < 6-mo-old infants before and after surgery for unilateral ureteropelvic junction obstruction (UJO). METHODS: The results obtained at diagnosis and after pyeloplasty for 9 children (8 boys, 1 girl; age range, 0.8-5.9 mo; mean age +/- SD, 2.4 +/- 1.5 mo) with proven unilateral UJO (i.e., affected kidney [AK]) and an unremarkable contralateral kidney (i.e., normal kidney [NK]) were evaluated and compared with a control group of 10 children (6 boys, 4 girls; age range, 0.8-2.8 mo; mean age, 1.5 +/- 0.7 mo) selected because of symmetric renal function, absence of vesicoureteral reflux or infection, and an initially dilated but not obstructed renal pelvis as proven by follow-up. Renography was performed for 20 min after injection of (123)I-hippuran (OIH) (0.5-1.0 MBq/kg) immediately followed by furosemide (1 mg/kg). The relative and absolute renal functions and the response to furosemide were measured on background-subtracted and depth-corrected renograms. The response to furosemide was quantified by an elimination index (EI), defined as the ratio of the 3- to 20-min activities: An EI > or = 3 was considered definitively normal and an EI < or = 1 definitively abnormal. If EI was equivocal (1 < EI < 3), the response to gravity-assisted drainage was used to differentiate AKs from NKs. Absolute separate renal function was measured by an accumulation index (AI), defined as the percentage of (123)I-OIH (%ID) extracted by the kidney 30-90 s after maximal cardiac activity. RESULTS: All AKs had definitively abnormal EIs at diagnosis (mean, 0.56 +/- 0.12) and were significantly lower than the EIs of the NKs (mean, 3.24 +/- 1.88) and of the 20 control kidneys (mean, 3.81 +/- 1.97; P < 0.001). The EIs of the AKs significantly improved (mean, 2.81 +/- 0.64; P < 0.05) after pyeloplasty. At diagnosis, the AIs of the AKs were significantly lower (mean, 6.31 +/- 2.33 %ID) than the AIs of the NKs (mean, 9.43 +/- 1.12 %ID) and of the control kidneys (mean, 9.05 +/- 1.17 %ID; P < 0.05). The AIs of the AKs increased at follow-up (mean, 7.81 +/- 2.23 %ID) but remained lower than those of the NKs (mean, 10.75 +/- 1.35 %ID; P < 0.05). CONCLUSION: In neonates and infants younger than 6 mo, (123)I-OIH renography with early furosemide injection (F+0) allowed us to reliably diagnose AKs and to determine if parenchymal function was normal or impaired and if it improved after surgery.

N-3 fatty acids, cancer and cachexia: a systematic review of the literature.

Use of n-3 fatty acids (FA) has been reported to be beneficial for cancer patients. We performed a systematic review of the literature in order to issue recommendations on the clinical use of n-3 FA in the cancer setting. A systematic search was performed in MEDLINE, EMBASE, Cochrane and Healthstar databases. We selected clinical trials or prospective observational studies including patients with cancer and life expectancy >2 months, in which enteral supplements with n-3 FA were administered. Parameters evaluated individually were clinical (nutritional status, tolerance, survival and hospital stays), biochemical (inflammatory mediators), and functional (functional status, appetite and quality of life (QoL)). Seventeen studies met the inclusion criteria; eight were of high quality. The panel of experts established the following evidence: (1) oral supplements with n-3 FA benefit patients with advanced cancer and weight loss, and are indicated in tumours of the upper digestive tract and pancreas; (2) the advantages observed were: increased weight and appetite, improved QoL, and reduced post-surgical morbidity; (3) there is no defined pattern for combining different n-3 FA, and it is recommended to administer > 1.5 g/day; and (4) better tolerance is obtained administering low-fat formulas for a period of at least 8 weeks. All the evidences were grade B but for 'length of treatment' and 'advantage of survival' it was grade C. Our findings suggest that administration of n-3 FA (EPA and DHA) in doses of at least 1.5 g/day for a prolonged period of time to patients with advanced cancer is associated with an improvement in clinical, biological and QoL parameters.

Birth and expression evolution of mammalian microRNA genes.

MicroRNAs (miRNAs) are major post-transcriptional regulators of gene expression, yet their origins and functional evolution in mammals remain little understood due to the lack of appropriate comparative data. Using RNA sequencing, we have generated extensive and comparable miRNA data for five organs in six species that represent all main mammalian lineages and birds (the evolutionary outgroup) with the aim to unravel the evolution of mammalian miRNAs. Our analyses reveal an overall expansion of miRNA repertoires in mammals, with threefold accelerated birth rates of miRNA families in placentals and marsupials, facilitated by the de novo emergence of miRNAs in host gene introns. Generally, our analyses suggest a high rate of miRNA family turnover in mammals with many newly emerged miRNA families being lost soon after their formation. Selectively preserved mammalian miRNA families gradually evolved higher expression levels, as well as altered mature sequences and target gene repertoires, and were apparently mainly recruited to exert regulatory functions in nervous tissues. However, miRNAs that originated on the X chromosome evolved high expression levels and potentially diverse functions during spermatogenesis, including meiosis, through selectively driven duplication-divergence processes. Overall, our study thus provides detailed insights into the birth and evolution of mammalian miRNA genes and the associated selective forces.

Aggravation of chronic stress effects on hippocampal neurogenesis and spatial memory in LPA₁ receptor knockout mice.

BACKGROUND The lysophosphatidic acid LPA₁ receptor regulates plasticity and neurogenesis in the adult hippocampus. Here, we studied whether absence of the LPA₁ receptor modulated the detrimental effects of chronic stress on hippocampal neurogenesis and spatial memory. METHODOLOGY/PRINCIPAL FINDINGS Male LPA₁-null (NULL) and wild-type (WT) mice were assigned to control or chronic stress conditions (21 days of restraint, 3 h/day). Immunohistochemistry for bromodeoxyuridine and endogenous markers was performed to examine hippocampal cell proliferation, survival, number and maturation of young neurons, hippocampal structure and apoptosis in the hippocampus. Corticosterone levels were measured in another a separate cohort of mice. Finally, the hole-board test assessed spatial reference and working memory. Under control conditions, NULL mice showed reduced cell proliferation, a defective population of young neurons, reduced hippocampal volume and moderate spatial memory deficits. However, the primary result is that chronic stress impaired hippocampal neurogenesis in NULLs more severely than in WT mice in terms of cell proliferation; apoptosis; the number and maturation of young neurons; and both the volume and neuronal density in the granular zone. Only stressed NULLs presented hypocortisolemia. Moreover, a dramatic deficit in spatial reference memory consolidation was observed in chronically stressed NULL mice, which was in contrast to the minor effect observed in stressed WT mice. CONCLUSIONS/SIGNIFICANCE These results reveal that the absence of the LPA₁ receptor aggravates the chronic stress-induced impairment to hippocampal neurogenesis and its dependent functions. Thus, modulation of the LPA₁ receptor pathway may be of interest with respect to the treatment of stress-induced hippocampal pathology.

Association between magnesium-deficient status and anthropometric and clinical-nutritional parameters in posmenopausal women.

Background: During menopause occurs weight gain and bone loss occurs due to the hormone decline during this period and other factors such as nutrition. Magnesium deficiency suggests a risk factor for obesity and osteoporosis. OBJECTIVE: To evaluate the clinical and nutritional magnesium status in a population of postmenopausal women, assessing intake and serum levels of magnesium in the study population and correlation with anthropometric parameters such as body mass index(BMI) and body fat, and biochemical parameters associated. SUBJECTS AND METHOD: The study involved 78 healthy women aged 44-76, with postmenopausal status, from the province of Grenade, Spain. The sample was divided into two age groups: group1, aged < 58, and group 2 aged >/= 58. Anthropometric parameters were recorded and nutritional intake was assessed by 72-hour recall, getting the RDAs through Nutriber(R) program. To assess the biochemical parameters was performed a blood sample was taken. Magnesium was analyzed by flame atomic absorption spectrophotometry (FAAS) in erythrocyte and plasma wet-mineralized samples. RESULTS: Our results show that 37.85% of the total subjects have an overweight status. Magnesium intake found in our population is insufficient in 36% of women,while plasma magnesium deficiency corresponds to 23% of the population and 72% of women have deficient levels of magnesium in erythrocyte. Positive correlations were found between magnesium intake and dietary intake of calcium, of phosphorus,and with prealbumin plasma levels, as well as with a lower waist / hip ratio Magnesium levels in erythrocyte were correlated with lower triglycerides and urea values. CONCLUSION: It is important to control and monitor the nutritional status of magnesium in postmenopausal women to prevent nutritional alterations and possible clinical and chronic degenerative diseases associated with magnesium deficiency and with menopause.

Mechanisms of growth inhibition of Phytomonas serpens by the alkaloids tomatine and tomatidine

Phytomonas serpens are flagellates in the family Trypanosomatidae that parasitise the tomato plant (Solanum lycopersicum L.), which results in fruits with low commercial value. The tomato glycoalkaloid tomatine and its aglycone tomatidine inhibit the growth of P. serpens in axenic cultures. Tomatine, like many other saponins, induces permeabilisation of the cell membrane and a loss of cell content, including the cytosolic enzyme pyruvate kinase. In contrast, tomatidine does not cause permeabilisation of membranes, but instead provokes morphological changes, including vacuolisation. Phytomonas treated with tomatidine show an increased accumulation of labelled neutral lipids (BODYPY-palmitic), a notable decrease in the amount of C24-alkylated sterols and an increase in zymosterol content. These results are consistent with the inhibition of 24-sterol methyltransferase (SMT), which is an important enzyme that is responsible for the methylation of sterols at the 24 position. We propose that the main target of tomatidine is the sterols biosynthetic pathway, specifically, inhibition of the 24-SMT. Altogether, the results obtained in the present paper suggest a more general effect of alkaloids in trypanosomatids, which opens potential therapeutic possibilities for the treatment of the diseases caused by these pathogens.

Contribution of efflux pumps, porins, and β-lactamases to multidrug resistance in clinical isolates of Acinetobacter baumannii.

We investigated the mechanisms of resistance to carbapenems, aminoglycosides, glycylcyclines, tetracyclines, and quinolones in 90 multiresistant clinical strains of Acinetobacter baumannii isolated from two genetically unrelated A. baumannii clones: clone PFGE-ROC-1 (53 strains producing the OXA-58 β-lactamase enzyme and 18 strains with the OXA-24 β-lactamase) and clone PFGE-HUI-1 (19 strains susceptible to carbapenems). We used real-time reverse transcriptase PCR to correlate antimicrobial resistance (MICs) with expression of genes encoding chromosomal β-lactamases (AmpC and OXA-51), porins (OmpA, CarO, Omp33, Dcap-like, OprB, Omp25, OprC, OprD, and OmpW), and proteins integral to six efflux systems (AdeABC, AdeIJK, AdeFGH, CraA, AbeM, and AmvA). Overexpression of the AdeABC system (level of expression relative to that by A. baumannii ATCC 17978, 30- to 45-fold) was significantly associated with resistance to tigecycline, minocycline, and gentamicin and other biological functions. However, hyperexpression of the AdeIJK efflux pump (level of expression relative to that by A. baumannii ATCC 17978, 8- to 10-fold) was significantly associated only with resistance to tigecycline and minocycline (to which the TetB efflux system also contributed). TetB and TetA(39) efflux pumps were detected in clinical strains and were associated with resistance to tetracyclines and doxycycline. The absence of the AdeABC system and the lack of expression of other mechanisms suggest that tigecycline-resistant strains of the PFGE-HUI-1 clone may be associated with a novel resistance-nodulation-cell efflux pump (decreased MICs in the presence of the inhibitor Phe-Arg β-naphthylamide dihydrochloride) and the TetA(39) system.

Vitellogenin Underwent Subfunctionalization to Acquire Caste and Behavioral Specific Expression in the Harvester Ant Pogonomyrmex barbatus.

The reproductive ground plan hypothesis (RGPH) proposes that the physiological pathways regulating reproduction were co-opted to regulate worker division of labor. Support for this hypothesis in honeybees is provided by studies demonstrating that the reproductive potential of workers, assessed by the levels of vitellogenin (Vg), is linked to task performance. Interestingly, contrary to honeybees that have a single Vg ortholog and potentially fertile nurses, the genome of the harvester ant Pogonomyrmex barbatus harbors two Vg genes (Pb_Vg1 and Pb_Vg2) and nurses produce infertile trophic eggs. P. barbatus, thus, provides a unique model to investigate whether Vg duplication in ants was followed by subfunctionalization to acquire reproductive and non-reproductive functions and whether Vg reproductive function was co-opted to regulate behavior in sterile workers. To investigate these questions, we compared the expression patterns of P. barbatus Vg genes and analyzed the phylogenetic relationships and molecular evolution of Vg genes in ants. qRT-PCRs revealed that Pb_Vg1 is more highly expressed in queens compared to workers and in nurses compared to foragers. By contrast, the level of expression of Pb_Vg2 was higher in foragers than in nurses and queens. Phylogenetic analyses show that a first duplication of the ancestral Vg gene occurred after the divergence between the poneroid and formicoid clades and subsequent duplications occurred in the lineages leading to Solenopsis invicta, Linepithema humile and Acromyrmex echinatior. The initial duplication resulted in two Vg gene subfamilies preferentially expressed in queens and nurses (subfamily A) or in foraging workers (subfamily B). Finally, molecular evolution analyses show that the subfamily A experienced positive selection, while the subfamily B showed overall relaxation of purifying selection. Our results suggest that in P. barbatus the Vg gene underwent subfunctionalization after duplication to acquire caste- and behavior- specific expression associated with reproductive and non-reproductive functions, supporting the validity of the RGPH in ants.

Visual loss after orthopedic procedures.

Perioperative visual loss (PVL) is a very rare and unpredictable complication of surgery performed at distance from the visual pathways, mostly after spine or cardiac procedures. We report 6 consecutive patients with PVL after routine orthopedic procedures (osteosynthesis for complex fracture of the femur [2], total hip arthroplasty [2], hip prosthesis arthroplasty [1], bilateral simultaneous total knee arthroplasty [1]) and reviewed the literature on the subject. An ischemic optic neuropathy was diagnosed in all cases, and visual loss was bilateral in 5 of 6 patients. Partial visual improvement occurred in only 3 of 11 eyes. No specific therapy is available for PVL. Postoperative visual disturbances should prompt without delay an ophthalmic evaluation because emergent correction of anemia, systemic hypotension, or hypovolemia might improve visual prognosis of PVL.