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Microbial cooperative behaviours, such as quorum sensing (QS), improve survival and this explains their prevalence throughout the microbial world. However, relatively little is known about the mechanisms by which cooperation promotes survival. Furthermore, cooperation typically requires costly contributions, e.g. exopolysaccharides, which are produced from limited resources. Inevitably, cooperation is vulnerable to damaging mutations which results in mutants that are relieved of the burden of contributing but nonetheless benefit from the contributions of their parent. Unless somehow prevented, such mutants may outcompete and replace the parent. The bacterium Sinorhizobium meliloti uses QS to activate the production of copious levels of exopolysaccharide (EPS). Domestication of this bacterium is typified by the appearance of spontaneous mutants incapable of EPS production, which take advantage of EPS production by the parent and outcompete the parent. We found that all of the mutants were defect in QS, implying that loss of QS is a typical consequence of the domestication of this bacterium. This instability was traced to several QS-regulated processes, including a QS-dependent restraint of growth, providing the mutant with a significant growth advantage. A model is proposed whereby QS restrains population growth to prevent overcrowding and prepares the population for the survival of severe conditions., (© 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Background: Swarming motility and biofilm formation are opposite, but related surface-associated behaviors that allow various pathogenic bacteria to colonize and invade their hosts. In Sinorhizobium meliloti, the alfalfa endosymbiont, these bacterial processes and their relevance for host plant colonization are largely unexplored. Our previous work demonstrated distinct swarming abilities in two S. meliloti strains (Rm1021 and GR4) and revealed that both environmental cues (iron concentration) and bacterial genes (fadD, rhb, rirA) play crucial roles in the control of surface motility in this rhizobial species. In the current study, we investigate whether these factors have an impact on the ability of S. meliloti to establish biofilms and to colonize host roots., Results: We found that strain GR4, which is less prone to translocate on solid surfaces than strain Rm1021, is more efficient in developing biofilms on glass and plant root surfaces. High iron conditions, known to prevent surface motility in a wild-type strain of S. meliloti, promote biofilm development in Rm1021 and GR4 strains by inducing the formation of more structured and thicker biofilms than those formed under low iron levels. Moreover, three different S. meliloti mutants (fadD, rhb, and rirA) that exhibit an altered surface translocation behavior compared with the wild-type strain, establish reduced biofilms on both glass and alfalfa root surfaces. Iron-rich conditions neither rescue the defect in biofilm formation shown by the rhb mutant, which is unable to produce the siderophore rhizobactin 1021 (Rhb1021), nor have any impact on biofilms formed by the iron-response regulator rirA mutant. On the other hand, S. meliloti FadD loss-of-function mutants do not establish normal biofilms irrespective of iron levels., Conclusions: Our studies show that siderophore Rhb1021 is not only required for surface translocation, but also for biofilm formation on glass and root surfaces by strain Rm1021. In addition, we present evidence for the existence of control mechanisms that inversely regulate swarming and biofilm formation in S. meliloti, and that contribute to efficient plant root colonization. One of these mechanisms involves iron levels and the iron global regulator RirA. The other mechanism involves the participation of the fatty acid metabolism-related enzyme FadD.

Here we report that the structure of the Sinorhizobium fredii HH103 exopolysaccharide (EPS) is composed of glucose, galactose, glucuronic acid, pyruvic acid, in the ratios 5∶2∶2∶1 and is partially acetylated. A S. fredii HH103 exoA mutant (SVQ530), unable to produce EPS, not only forms nitrogen fixing nodules with soybean but also shows increased competitive capacity for nodule occupancy. Mutant SVQ530 is, however, less competitive to nodulate Vigna unguiculata. Biofilm formation was reduced in mutant SVQ530 but increased in an EPS overproducing mutant. Mutant SVQ530 was impaired in surface motility and showed higher osmosensitivity compared to its wild type strain in media containing 50 mM NaCl or 5% (w/v) sucrose. Neither S. fredii HH103 nor 41 other S. fredii strains were recognized by soybean lectin (SBL). S. fredii HH103 mutants affected in exopolysaccharides (EPS), lipopolysaccharides (LPS), cyclic glucans (CG) or capsular polysaccharides (KPS) were not significantly impaired in their soybean-root attachment capacity, suggesting that these surface polysaccharides might not be relevant in early attachment to soybean roots. These results also indicate that the molecular mechanisms involved in S. fredii attachment to soybean roots might be different to those operating in Bradyrhizobium japonicum.

Psoriatic lesions affecting the scalp, nails, palms, and the soles of the feet are described as difficult-to-treat psoriasis and require specific management. Involvement of these sites often has a significant physical and emotional impact on the patient and the lesions are difficult to control with topical treatments owing to inadequate penetration of active ingredients and the poor cosmetic characteristics of the vehicles used. Consequently, when difficult-to-treat sites are involved, psoriasis can be considered severe even though the lesions are not extensive. Scant information is available about the use of biologic therapy in this setting, and published data generally comes from clinical trials of patients who also had moderate to severe extensive lesions or from small case series and isolated case reports. In this article we review the quality of the scientific evidence for the 4 biologic agents currently available in Spain (infliximab, etanercept, adalimumab, and ustekinumab) and report level i evidence for the use of biologics to treat nail psoriasis (level of recommendation A) and a somewhat lower level of evidence in the case of scalp involvement and palmoplantar psoriasis., (Copyright © 2013 Elsevier España, S.L.U. y AEDV. All rights reserved.)

Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is an opportunistic pathogen that colonizes the gastrointestinal and genitourinary tracts of up to 50% of healthy adults and newborns; it is responsible for significant morbidity and mortality. Early detection can be used to establish the use of antibiotic prophylaxis to significantly reduce neonatal sepsis. This article reviews methods of detection and prevention of GBS infection in the neonate.

Multiple osteochondromatosis can become malignant in 20% of the cases, this being more common when the lesion is multiple than when it is solitary. A male patient with multiple osteochondromatosis who had several local recurrences of secondary chondrosarcoma and who is still under follow-up by the Nuclear Medicine Department is presented. The bone scintigraphy findings were compared with the histopathologic results, and the importance of the patient's symptoms was verified when a sarcomatous transformation is suspected. The bone scintigraphy has the potential to detect malignization of the benign bone lesions. It also makes it possible to obtain whole-body images in a single examination, this being very useful to detect the presence of new bone lesions., (Copyright © 2011 Elsevier España, S.L. y SEMNIM. All rights reserved.)

The Sinorhizobium fredii HH103 rkp-3 region has been isolated and sequenced. Based on the similarities between the S. fredii HH103 rkpL, rkpM, rkpN, rkpO, rkpP, and rkpQ genes and their corresponding orthologues in Helicobacter pylori, we propose a possible pathway for the biosynthesis of the S. fredii HH103 K-antigen polysaccharide (KPS) repeating unit. Three rkp-3 genes (rkpM, rkpP, and rkpQ) involved in the biosynthesis of the HH103 KPS repeating unit (a derivative of the pseudaminic acid) have been mutated and analyzed. All the rkp-3 mutants failed to produce KPS and their lipopolysaccharide (LPS) profiles were altered. These mutants showed reduced motility and auto-agglutinated when early-stationary cultures were further incubated under static conditions. Glycine max, Vigna unguiculata (determinate nodule-forming legumes), and Cajanus cajan (indeterminate nodules) plants inoculated with mutants in rkpM, rkpQ, or rkpP only formed pseudonodules that did not fix nitrogen and were devoid of bacteria. In contrast, another indeterminate nodule-forming legume, Glycyrrhiza uralensis, was still able to form some nitrogen-fixing nodules with the three S. fredii HH103 rifampicin-resistant rkp-3 mutants tested. Our results suggest that the severe symbiotic impairment of the S. fredii rkp-3 mutants with soybean, V. unguiculata, and C. cajan is mainly due to the LPS alterations rather than to the incapacity to produce KPS.

Swarming is a mode of translocation dependent on flagellar activity that allows bacteria to move rapidly across surfaces. In several bacteria, swarming is a phenotype regulated by quorum sensing. It has been reported that the swarming ability of the soil bacterium Sinorhizobium meliloti Rm2011 requires a functional ExpR/Sin quorum-sensing system. However, our previous published results demonstrate that strains Rm1021 and Rm2011, both known to have a disrupted copy of expR, are able to swarm on semisolid minimal medium. In order to clarify these contradictory results, the role played by the LuxR-type regulator ExpR has been reexamined. Results obtained in this work revealed that S. meliloti can move over semisolid surfaces using at least two different types of motility. One type is flagellum-independent surface spreading or sliding, which is positively influenced by a functional expR gene mainly through the production of exopolysaccharide II (EPS II). To a lesser extent, EPS II-deficient strains can also slide on surfaces by a mechanism that is at least dependent on the siderophore rhizobactin 1021. The second type of surface translocation shown by S. meliloti is swarming, which is greatly dependent on flagella and rhizobactin 1021 but does not require ExpR. We have extended our study to demonstrate that the production of normal amounts of succinoglycan (EPS I) does not play a relevant role in surface translocation but that its overproduction facilitates both swarming and sliding motilities.

Objective: The aim of this study was to assess whether measurement of hepatitis C virus RNA (HCV-RNA) at 12 weeks post-treatment could predict sustained virological response (SVR) to antiviral therapy for chronic hepatitis C (pegylated interferon alfa-2a and ribavirin) in HIV-co-infected patients., Patients and Methods: HIV-HCV co-infected patients were included if they completed a full course of anti-HCV therapy, achieved an end-of-treatment response and complied with the week +12 and +24 post-treatment follow-up schedule for serum HCV-RNA determination (Real-time HCV (Abbott, Wiesbaden, Germany) (lower limit of detection, 12 IU/ml)., Results: Forty out of 66 patients (61%) showed an end-of-treatment response. They were assessed in a follow-up visit at +12 and at +24 weeks post-treatment. Serum HCV-RNA was undetectable in 28 of them at +12 weeks, and 100% of these remained undetectable at 24 weeks post-treatment (the gold standard of (SVR). The positive predictive value was 100% (95% confidence interval, 98.21-100%)., Conclusion: Post-treatment follow-up to identify virological relapse could be shortened to 12 weeks, providing a new definition of sustained virological response., (Copyright © 2011 Elsevier España, S.L. All rights reserved.)

FadD is an acyl coenzyme A (CoA) synthetase responsible for the activation of exogenous long-chain fatty acids (LCFA) into acyl-CoAs. Mutation of fadD in the symbiotic nitrogen-fixing bacterium Sinorhizobium meliloti promotes swarming motility and leads to defects in nodulation of alfalfa plants. In this study, we found that S. meliloti fadD mutants accumulated a mixture of free fatty acids during the stationary phase of growth. The composition of the free fatty acid pool and the results obtained after specific labeling of esterified fatty acids with a Δ5-desaturase (Δ5-Des) were in agreement with membrane phospholipids being the origin of the released fatty acids. Escherichia coli fadD mutants also accumulated free fatty acids released from membrane lipids in the stationary phase. This phenomenon did not occur in a mutant of E. coli with a deficient FadL fatty acid transporter, suggesting that the accumulation of fatty acids in fadD mutants occurs inside the cell. Our results indicate that, besides the activation of exogenous LCFA, in bacteria FadD plays a major role in the activation of endogenous fatty acids released from membrane lipids. Furthermore, expression analysis performed with S. meliloti revealed that a functional FadD is required for the upregulation of genes involved in fatty acid degradation and suggested that in the wild-type strain, the fatty acids released from membrane lipids are degraded by β-oxidation in the stationary phase of growth.

The kinetics of the thermal hydrolysis of the fructans of Agave salmiana were determined during the cooking step of mezcal production in a pilot autoclave. Thermal hydrolysis was achieved at different temperatures and cooking times, ranging from 96 to 116 °C and from 20 to 80 h. A simple kinetic model of the depolymerization of fructans to monomers and other reducing sugars and of the degradation of reducing sugars to furans [principally 5-(hydroxymethyl)furfural, HMF] was developed. From this model, the rate constants of the reactions were calculated, as well as the pre-exponential factors and activation energies of the Arrhenius equation. The model was found to fit the experimental data well. The tradeoff between a maximum fructan hydrolysis and a critical furan concentration in allowing for the best ethanol yield during fermentation was investigated. The results indicated that the thermal hydrolysis of agave was optimal, from the point of view of ethanol yield in the ensuing fermentation, in the temperature range of 106-116 °C and the cooking range time of 6-14 h. The optimal conditions corresponded to a fructan hydrolysis of 80%, producing syrups with furan and reducing sugar concentrations of 1 ± 0.1 and 110 ± 10 g/L, respectively.

Background and Aims: Analysis of the influence of the effects of increased intestinal permeability on haemodynamic alterations in human immunodeficiency virus (HIV)-infected patients with decompensated hepatitis C virus (HCV)-related liver disease., Methods: Forty HIV/HCV co-infected patients and 40 HCV mono-infected patients, 20 of them with compensated cirrhosis and 20 with a previous decompensation, and 20 healthy controls, were studied. Intestinal permeability was determined by serum levels of lipopolysaccharide-binding protein (LBP). Monocyte expression of toll-like receptor 4 (TLR-4), serum levels of interleukin (IL)-6 and soluble receptors of tumour necrosis factor (sTNFRI) were analysed. Cardiac index, systemic vascular resistance (SVR), plasma renin activity (PRA) and aldosterone concentration were also determined in cirrhotic patients., Results: Serum levels of LBP, TLR-4, IL-6 and sTNFRI were significantly higher in HIV-HCV co-infected and HCV mono-infected patients with decompensated cirrhosis compared with those with compensated liver disease. Significantly lower values of SVR and higher values of cardiac index, PRA and aldosterone concentration were observed in patients with decompensated cirrhosis compared with those with compensated liver disease, particularly in those with elevated levels of IL-6. There were no significant differences between HIV/HCV co-infected and HCV mono-infected patients., Conclusions: Higher intestinal permeability and consequent macrophage activation is observed in patients with cirrhosis; this permeability is even higher in those with portal hypertension. Serum values of IL-6 are associated with the characteristic haemodynamic derangement observed in advanced phases of cirrhosis. HIV/HCV co-infected cirrhotic patients present inflammatory and systemic haemodynamic alterations similar to those observed in HCV mono-infected patients., (© 2011 John Wiley & Sons A/S.)

The establishment of rhizobia as nitrogen-fixing endosymbionts within legume root nodules requires the disruption of the plant cell wall to breach the host barrier at strategic infection sites in the root hair tip and at points of bacterial release from infection threads (IT) within the root cortex. We previously found that Rhizobium leguminosarum bv. trifolii uses its chromosomally encoded CelC2 cellulase to erode the noncrystalline wall at the apex of root hairs, thereby creating the primary portal of its entry into white clover roots. Here, we show that a recombinant derivative of R. leguminosarum bv. trifolii ANU843 that constitutively overproduces the CelC2 enzyme has increased competitiveness in occupying aberrant nodule-like root structures on clover that are inefficient in nitrogen fixation. This aberrant symbiotic phenotype involves an extensive uncontrolled degradation of the host cell walls restricted to the expected infection sites at tips of deformed root hairs and significantly enlarged infection droplets at termini of wider IT within the nodule infection zone. Furthermore, signs of elevated plant host defense as indicated by reactive oxygen species production in root tissues were more evident during infection by the recombinant strain than its wild-type parent. Our data further support the role of the rhizobial CelC2 cell wall-degrading enzyme in primary infection, and show evidence of its importance in secondary symbiotic infection and tight regulation of its production to establish an effective nitrogen-fixing root nodule symbiosis.

The mechanistic basis of the target-site preference of lentivirus DNA integration is not well understood. In the present in silico study, we describe the integrational profile of simultaneous HIV-1 and HIV-2 infection. A total of 352 genomic DNA sequences from human peripheral blood mononuclear cells (PBMCs) obtained from GenBank and possessing the 5' LTR of HIV were used to characterize the structure and composition of local chromatin associated with high frequency integration sites. These sequences were aligned with the draft human genome (hg18) using BLAST (NCBI) and BLAT (UCSC) in order to derive information about chromosome localization, functional aspects of coding protein genes, CpG island number, and repetitive elements flanking integration sites. No significant differences in the integrational profile between HIV-1 and HIV-2 were found. However, we observed a tendency in both lentiviruses to integrate in the vicinity of protein coding genes. Multiple regression analysis showed a strong correlation between the number of genes and the number of CpG islands in regions with high integration frequency, mainly in chromosome 17 (R = 0.95, p < 0.05). Our results provide strong evidence that HIV-1 and HIV-2 have common genomic environments in the local chromatin regions with high gene density and CpG islands. The understanding of local genomic environments with a high frequency of integration would be the starting point to develop novel antiviral strategies for lentiviral infection.

Objective: Analysis of the influence of portal hypertension on intestinal permeability in HIV-infected patients with hepatitis C virus (HCV)-related cirrhosis and of the prognostic significance of consequent macrophage activation., Methods: Twenty HIV-monoinfected patients, 70 patients with HIV-HCV coinfection, 20 of them with compensated and 50 with decompensated cirrhosis, and 20 healthy controls were evaluated for intestinal permeability [measured by lipopolysaccharide-binding protein (LBP) serum levels], macrophage activation [soluble CD14, soluble tumour necrosis factor receptor 55 Kd, and interleukin 6 (IL-6)], and activation of the rennin-angiotensin-aldosterone axis. Patients with decompensated cirrhosis were monitored for a median period of 429 days to analyze the prognostic factors implicated in survival., Results: Patients with decompensated cirrhosis show increased LBP levels compared with HIV-monoinfected patients. Patients with increased LBP concentration showed elevated soluble CD14, soluble tumour necrosis factor receptor 55 Kd, and IL-6 levels. Twenty-two patients died, from liver-related causes, during the follow-up, and 2 more underwent liver transplantation. Child-Pugh index, CD4 T-cell count, plasma aldosterone and serum IL-6 concentrations independently predicted liver-related mortality., Conclusions: Increased intestinal permeability, as measured by serum LBP levels, observed in patients with HIV infection is significantly higher in patients with decompensated liver cirrhosis. Proinflammatory cytokines (IL-6) are prognostic markers of HIV-HCV-coinfected patients with decompensated cirrhosis.

Sinorhizobium meliloti 1021 carries two megaplasmids, pSymA of 1,354 kb and pSymB of 1,683 kb, which are essential in establishing symbiosis with its legume hosts and important for bacterial fitness in the rhizosphere. We have previously shown that pSymA is self-transmissible and that its conjugal functions are regulated by the transcriptional repressor RctA. Here, we show conjugal transfer of pSymB as an in trans mobilization event that requires the type IV secretion system encoded by pSymA. pSymB carries a functional oriT and an adjacent relaxase gene, traA2, that is also transcriptionally repressed by rctA. Both symbiotic megaplasmids would require the relaxase genes in cis with their respective oriTs to achieve the highest transfer efficiencies.

Background: Features of the area might contribute to differences in cardiovascular mortality. The census tract distribution of ischaemic heart disease (IHD) and cerebrovascular disease mortality in the Region of Madrid and its association with deprivation and environmental variables were examined in this study., Methods: Cross-sectional, ecological study covering 3906 census tracts (median of around 1000 inhabitants), using mortality data (population aged <75 years) for 1996-2003, as well as socioeconomic deprivation and other environmental indicators (subjective perceptions of pollution, background noise, lack of green spaces and delinquency) drawn from the 2001 census. Standardised mortality ratios were calculated. Smoothed census tract relative risks were calculated using the Besag-York-Mollié model. Relative risks (RRs) of dying and their 95% credibility intervals (95% CI) were calculated according to the indicators considered (with the fourth quartile, Q, being the most unfavourable situation). Maps were plotted depicting the distribution of the posterior probability of RR>1., Results: Census tracts with excess mortality were mostly located in the city of Madrid. Mortality increased with deprivation: RRs of IHD and stroke mortality in Q4 with respect to Q1 were 1.42 (95% CI 1.31 to 1.54) and 1.66 (95% CI 1.45 to 1.88) for men, and 1.54 (95% CI 1.33 to 1.79) and 1.52 (95% CI 1.29 to 1.76) for women respectively. Associations with deprivation decreased only slightly when perceived lack of green spaces and delinquency were included in the model. In men, subjective perceptions of areas remained associated with cardiovascular mortality after adjustment for deprivation., Conclusion: Deprivation and subjective perceptions of physical environmental characteristics are ecologically associated with cardiovascular disease mortality.

Lotus species are forage legumes with potential as pastures in low-fertility and environmentally constrained soils, owing to their high persistence and yield under those conditions. The aim of this work was the characterization of phenetic and genetic diversity of salt-tolerant bacteria able to establish efficient symbiosis with Lotus spp. A total of 180 isolates able to nodulate Lotus corniculatus and Lotus tenuis from two locations in Granada, Spain, were characterized. Molecular identification of the isolates was performed by repetitive extragenic palindromic PCR (REP-PCR) and 16S rRNA, atpD, and recA gene sequence analyses, showing the presence of bacteria related to different species of the genus Mesorhizobium: Mesorhizobium tarimense/Mesorhizobium tianshanense, Mesorhizobium chacoense/Mesorhizobium albiziae, and the recently described species, Mesorhizobium alhagi. No Mesorhizobium loti-like bacteria were found, although most isolates carried nodC and nifH symbiotic genes closely related to those of M. loti, considered the type species of bacteria nodulating Lotus, and other Lotus rhizobia. A significant portion of the isolates showed both high salt tolerance and good symbiotic performance with L. corniculatus, and many behaved like salt-dependent bacteria, showing faster growth and better symbiotic performance when media were supplemented with Na or Ca salts.

Mandibular osteoradionecrosis is a serious complication of radiotherapy that often leads to severe facial deformity, intolerable pain, fracture, sequestration of devitalized bone and fistulas. The prophylaxis of this severe complication is a major goal in modern combined tumor therapy, but once the pathology is established, conservative treatment modalities are used in almost all patients in an effort to control progression. Radical surgery should only be instituted when conservative methods fail or when severe bone and soft-tissue necrosis prevails. Pathologic fractures and chronic fistulae are clear indicators for radical surgical management. This paper document a case report of severe bilateral mandibular osteoradionecrosis reconstructed with two sequencial osteocutaneous fibular free flap. The authors discuss the different alternatives of treatment and the most important steps for a successful management of this challenge.

The current 2002 classification criteria do not cover the broad clinical and immunological heterogeneity of primary Sjögren syndrome (SS), since five of the six criteria focus exclusively on glandular involvement and the remaining criterion is the mandatory presence of anti-Ro/La antibodies. The aim of this study was to analyze the clinical features of patients with a well-established diagnosis of primary SS who do not fulfill the 2002 classification criteria. Five hundred seven patients diagnosed with primary SS (1993 criteria) were consecutively included and followed up. Two hundred twenty-one (44%) patients did not fulfill the 2002 criteria. These patients were older at diagnosis (p < 0.001) and had a lower frequency of parotid enlargement (p = 0.002), fever (p = 0.041), arthritis (p = 0.041), vasculitis (p = 0.050), peripheral neuropathy (p = 0.002), cranial nerve involvement (p = 0.015), raised erythrocyte sedimentation rate ( ESR) levels (p < 0.001), anemia (p < 0.001), leukopenia (p = 0.037), hypergammaglobulinemia (p < 0.001), positive rheumatoid factor ( RF; p = 0.002), and cryoglobulinemia (p = 0.049) in comparison with those fulfilling 2002 criteria. However, there were no significant differences in the prevalence of sicca features, diagnostic tests, overall systemic involvement, antinuclear antibodies , complement levels, development of B-cell lymphoma, or survival. Patients with anti-Ro antibodies had the highest frequencies of systemic features, hematological abnormalities, and altered immunological markers. In conclusion, patients fulfilling the 2002 criteria, who have either a specific histological diagnosis (lymphocytic infiltration) or highly specific autoantibodies (Ro/La), might well be considered to have Sjögren "disease." In contrast, etiopathogenic mechanisms other than lymphocytic-mediated epithelial damage could be involved in patients with negative Ro and negative biopsy, in whom the term Sjögren "syndrome" seems more adequate.

Background: Swarming is a multicellular phenomenom characterized by the coordinated and rapid movement of bacteria across semisolid surfaces. In Sinorhizobium meliloti this type of motility has been described in a fadD mutant. To gain insights into the mechanisms underlying the process of swarming in rhizobia, we compared the transcriptome of a S. meliloti fadD mutant grown under swarming inducing conditions (semisolid medium) to those of cells grown under non-swarming conditions (broth and solid medium)., Results: More than a thousand genes were identified as differentially expressed in response to growth on agar surfaces including genes for several metabolic activities, iron uptake, chemotaxis, motility and stress-related genes. Under swarming-specific conditions, the most remarkable response was the up-regulation of iron-related genes. We demonstrate that the pSymA plasmid and specifically genes required for the biosynthesis of the siderophore rhizobactin 1021 are essential for swarming of a S. meliloti wild-type strain but not in a fadD mutant. Moreover, high iron conditions inhibit swarming of the wild-type strain but not in mutants lacking either the iron limitation response regulator RirA or FadD., Conclusions: The present work represents the first transcriptomic study of rhizobium growth on surfaces including swarming inducing conditions. The results have revealed major changes in the physiology of S. meliloti cells grown on a surface relative to liquid cultures. Moreover, analysis of genes responding to swarming inducing conditions led to the demonstration that iron and genes involved in rhizobactin 1021 synthesis play a role in the surface motility shown by S. meliloti which can be circumvented in a fadD mutant. This work opens a way to the identification of new traits and regulatory networks involved in swarming by rhizobia.

Background: Adverse outcomes resulting from aspiration or ingestion of instruments and materials can occur in any dental procedure. Clinical manifestation depends on the location, the obstructive potential of the foreign body, and the temporal factor since the accidental incident. Accidental inhalation of dental appliances can be an even more serious event than ingestion and must always be treated as an emergency situation., Case Report: A 62-year-old woman was admitted to our hospital with the suspicion of ingestion of a screwdriver implants. In spite of the clinically asymptomatic presentation, chest radiography in posteroanterior and lateral projections showed a radiopaque dental instrument impacted on the right main inferior bronchus. Rigid bronchoscope was successful to remove the dental instrument under general anesthesia, and the patient was discharged 24 h later., Conclusion: Aspiration and ingestion of dental foreign objects are infrequent, but they can occur at large multidisciplinary dental procedures. These episodes have the potential to result in acute medical and life-threatening emergencies since the beginning of the event or at a late stage in proceeding in the underdiagnosed patient. Prevention of such incidents is, therefore, the best approach via the mandatory use of precautions during all dental procedures, and in case of suspicion with no retrievable material, patient must always be submitted to a radiographic study.

Objective: To evaluate the association between the degree of involvement shown by parotid scintigraphy at diagnosis and the disease expression, outcomes, and prognosis of primary Sjögren's syndrome (SS)., Methods: All patients consecutively diagnosed with primary SS in our department between 1984 and 2008 were evaluated. The scintigraphic stages were classified into class 4 (severe involvement), class 2-3 (mild to moderate involvement), and class 1 (normal results)., Results: A total of 405 patients with primary SS underwent parotid scintigraphy at diagnosis (47 had class 1 involvement, 314 had class 2-3, and 44 had class 4). Patients with class 4 had a higher frequency of parotid enlargement (p < 0.001), systemic involvement (p = 0.007), high titers of antinuclear antibody (p = 0.016), positive rheumatoid factor (p = 0.002), anti-Ro/SSA (p = 0.001), anti-La/SSB (p = 0.001), low C4 levels (p = 0.001), and low CH50 (p = 0.001) in comparison with the other 2 groups. A higher rate of lymphoma development was observed in patients with class 4 involvement. Adjusted multivariate Cox regression analysis showed a hazard ratio (HR) of 10.51 (p = 0.002) and Kaplan-Meier analysis a log-rank of 0.0005. Mortality was 5-fold higher in patients with class 4 involvement. Adjusted multivariate Cox regression analysis showed an HR of 5.33 (p = 0.001) and Kaplan-Meier analysis a log-rank of 0.033., Conclusion: Patients with SS presenting with severe scintigraphic involvement at diagnosis had a more pronounced autoimmune expression, a higher risk of developing systemic features and lymphoma, and a lower survival rate. Study of the degree of salivary gland dysfunction at diagnosis by parotid scintigraphy offers valuable clinical information on the prognosis and outcome of primary SS.

The disaccharide trehalose is a well-known osmoprotectant, and trehalose accumulation through de novo biosynthesis is a common response of bacteria to abiotic stress. In this study, we have investigated the role of endogenous trehalose synthesis in the osmotolerance of Sinorhizobium meliloti. Genes coding for three possible trehalose synthesis pathways are present in the genome of S. meliloti 1021: OtsA, TreYZ, and TreS. Among these, OtsA has a major role in trehalose accumulation under all of the conditions tested and is the main system involved in osmoadaptation. Nevertheless, the other two systems are also important for growth in hyperosmotic medium. Genes for the three pathways are transcriptionally responsive to osmotic stress. The presence of at least one functional trehalose biosynthesis pathway is required for optimal competitiveness of S. meliloti to nodulate alfalfa roots.

We assessed the capacity of two liquid-medium culture methods with automated incubation and reading systems (MB/BacT ALERT 3D System and BACTEC MGIT 960 System) and one solid-medium culture method (Löwenstein- Jensen) to detect mycobacteria in different types of clinical samples. Out of 1,770 cultured clinical samples (1,519 of respiratory origin and 251 of nonrespiratory origin), mycobacteria were isolated in 156 samples (135 M. tuberculosis complex, 8 M. chelonae, 6 M. kansasii, 4 M. fortuitum, 2 M. gordonae, and 1 M. marinum) by at least one of the methods used. The BACTEC MGIT 960 System proved to be the most sensitive method (86.5%), especially in the detection of M. tuberculosis complex (89.1%). However, Löwenstein- Jensen culture was the most sensitive (76.2%) to detect nontuberculous mycobacteria. The BACTEC MGIT 960 System showed the lowest mean detection time for mycobacterial growth (15.3 days), significantly shorter than the other two methods. Highest sensitivity (95.5%) and specificity (99.6%) values were obtained using the BACTEC MGIT 960 System with the Löwenstein-Jensen culture method, which was also the only combination capable of detecting 100% of the nontuberculous mycobacteria.

The complexity of the therapeutic approach in systemic lupus erythematosus (SLE) is increased by the large number of patients who do not respond to the first-line therapies and by relapses after initial clinical remission. In these patients, second-line drugs are often prescribed according to individual clinical decisions. The emergence of biological therapies has increased the therapeutic armamentarium available in these complex situations, but their use is limited by the lack of licensing. Available data on the use of rituximab in SLE rely on a large number of case reports and some observational studies. We analyzed current evidence on the therapeutic use of rituximab in adult SLE patients by a systematic review of reports included in the PubMed database between 2002 and 2007. A total of 188 SLE patients treated with rituximab were identified; 171 (91%) patients showed a significant improvement in one or more of the systemic SLE manifestations. There were 103 patients with lupus nephritis, with an overall rate of therapeutic response of renal involvement of 91%. Adverse events were reported in 44 (23%) patients; the most frequent were infections (19%). Although it is not yet possible to make definite recommendations, the global analysis of all cases reported to date support the off-label use of rituximab in severe, refractory SLE cases, whereas its use as a first-line therapy or in patients with a predominantly mild form of the disease is not advised.

Stimulation of potassium uptake is the most rapid response to an osmotic upshock in bacteria. This cation accumulates by a number of different transport systems whose importance has not been previously addressed for rhizobia. In silico analyses reveal the presence of genes encoding four possible potassium uptake systems in the genome of Sinorhizobium meliloti 1021: Kup1, Kup2, Trk, and Kdp. The study of the relevance of these systems under a number of different growth conditions and in symbiosis showed that the integrity of Kup1 or Trk is essential for growth under laboratory conditions even in osmotically balanced media and the absence of both systems leads to a reduced infectivity and competitiveness of the bacteria in alfalfa roots. Trk is the main system involved in the accumulation of potassium after an osmotic upshift and the most important system for growth of S. meliloti under hyperosmotic conditions. The other three systems, especially Kup1, are also relevant during the osmotic adaptation of the cell, and the relative importance of the Kdp system increases at low potassium concentrations.

Pathogenic bacteria and mutualistic rhizobia are able to invade and establish chronic infections within their host plants. The success of these plant-bacteria interactions requires evasion of the plant innate immunity by either avoiding recognition or by suppressing host defences. The primary plant innate immunity is triggered upon recognition of common microbe-associated molecular patterns. Different studies reveal striking similarities between the molecular bases underlying the perception of rhizobial nodulation factors and microbe-associated molecular patterns from plant pathogens. However, in contrast to general elicitors, nodulation factors can control plant defences when recognized by their cognate legumes. Nevertheless, in response to rhizobial infection, legumes show transient or local defence-like responses suggesting that Rhizobium is perceived as an intruder although the plant immunity is controlled. Whether these responses are involved in limiting the number of infections or whether they are required for the progression of the interaction is not yet clear. Further similarities in both plant-pathogen and Rhizobium-legume associations are factors such as surface polysaccharides, quorum sensing signals and secreted proteins, which play important roles in modulating plant defence responses and determining the outcome of the interactions.

A total of 103 root nodule isolates were used to estimate the diversity of bacteria nodulating Lotus tenuis in typical soils of the Salado River Basin. A high level of genetic diversity was revealed by repetitive extragenic palindromic PCR, and 77 isolates with unique genomic fingerprints were further differentiated into two clusters, clusters A and B, after 16S rRNA restriction fragment length polymorphism analysis. Cluster A strains appeared to be related to the genus Mesorhizobium, whereas cluster B was related to the genus Rhizobium. 16S rRNA sequence and phylogenetic analysis further supported the distribution of most of the symbiotic isolates in either Rhizobium or Mesorhizobium: the only exception was isolate BA135, whose 16S rRNA gene was closely related to the 16S rRNA gene of the genus Aminobacter. Most Mesorhizobium-like isolates were closely related to Mesorhizobium amorphae, Mesorhizobium mediterraneum, Mesorhizobium tianshanense, or the broad-host-range strain NZP2037, but surprisingly few isolates grouped with Mesorhizobium loti type strain NZP2213. Rhizobium-like strains were related to Rhizobium gallicum, Rhizobium etli, or Rhizobium tropici, for which Phaseolus vulgaris is a common host. However, no nodC or nifH genes could be amplified from the L. tenuis isolates, suggesting that they have rather divergent symbiosis genes. In contrast, nodC genes from the Mesorhizobium and Aminobacter strains were closely related to nodC genes from narrow-host-range M. loti strains. Likewise, nifH gene sequences were very highly conserved among the Argentinian isolates and reference Lotus rhizobia. The high levels of conservation of the nodC and nifH genes suggest that there was a common origin of the symbiosis genes in narrow-host-range Lotus symbionts, supporting the hypothesis that both intrageneric horizontal gene transfer and intergeneric horizontal gene transfer are important mechanisms for the spread of symbiotic capacity in the Salado River Basin.

Background: Soil bacteria collectively known as Rhizobium, characterized by their ability to establish beneficial symbiosis with legumes, share several common characteristics with pathogenic bacteria when infecting the host plant. Recently, it was demonstrated that a fadD mutant of Sinorhizobium meliloti is altered in the control of swarming, a type of co-ordinated movement previously associated with pathogenicity, and is also impaired in nodulation efficiency on alfalfa roots. In the phytopathogen Xanthomonas campestris, a fadD homolog (rpfB) forms part of a cluster of genes involved in the regulation of pathogenicity factors. In this work, we have investigated the role in swarming and symbiosis of SMc02161, a S. meliloti fadD-linked gene., Results: The SMc02161 locus in S. meliloti shows similarities with members of the Major Facilitator Superfamily (MFS) of transporters. A S. meliloti null-mutant shows increased sensitivity to chloramphenicol. This indication led us to rename the locus tep1 for transmembrane efflux protein. The lack of tep1 does not affect the appearance of swarming motility. Interestingly, nodule formation efficiency on alfalfa plants is improved in the tep1 mutant during the first days of the interaction though nod gene expression is lower than in the wild type strain. Curiously, a nodC mutation or the addition of N-acetyl glucosamine to the wild type strain lead to similar reductions in nod gene expression as in the tep1 mutant. Moreover, aminosugar precursors of Nod factors inhibit nodulation., Conclusion: tep1 putatively encodes a transmembrane protein which can confer chloramphenicol resistance in S. meliloti by expelling the antibiotic outside the bacteria. The improved nodulation of alfalfa but reduced nod gene expression observed in the tep1 mutant suggests that Tep1 transports compounds which influence nodulation. In contrast to Bradyrhizobium japonicum, we show that in S. meliloti there is no feedback regulation of nodulation genes. Moreover, the Nod factor precursor, N-acetyl glucosamine reduces nod gene expression and nodulation efficiency when present at millimolar concentrations. A role for Tep1 in the efflux of Nod factor precursors could explain the phenotypes associated with tep1 inactivation.

A prospective study of 37 patients with pSS and 20 healthy controls was performed to analyze the differences in circulating levels of macrophage-derived and Th1/Th2 cytokines which could explain the hyperimmunoglobulinemia, characteristic of primary Sjögren's syndrome (pSS). Serum levels of interleukin (IL)-6, IL-10, IL-12, gamma-interferon (gamma-INF) and IL-4 were analyzed by a sandwich immunoassay-based protein array system. When compared with the control group, higher levels of IL-6, IL-12 and IL-10 and a lower Th1/Th2 ratio, as demonstrated by the gamma-INF/IL-4 ratio, were detected in patients. The levels of IL-4 were notably higher in pSS patients with monoclonal gammopathy. Serum IL-4 and IL-10 levels and immunoglobulin G concentrations were significantly correlated. In conclusion, patients with pSS show a state of macrophage and T-lymphocyte activation with increased concentrations of cytokines implicated in the differentiation of B cells and secretion of immunoglobulins.

Anti-TNF agents are increasingly being used for a rapidly expanding number of rheumatic and systemic autoimmune diseases. As a result of this use, and of the longer follow-up periods of treatment, there are a growing number of reports of the development of autoimmune processes related to anti-TNF agents. The clinical characteristics, outcomes, and patterns of association with the different anti-TNF agents used in all reports of autoimmune diseases developing after TNF-targeted therapy, were analyzed through a baseline Medline search of articles published between January 1990 and May 2008 (www.biogeas.org). A total of 379 cases of autoimmune diseases secondary to TNF-targeted therapies were identified. The anti-TNF agents were administered for rheumatoid arthritis in more than 80% of cases. The use of anti-TNF agents has been associated with an increasing number of cases of autoimmune diseases, principally cutaneous vasculitis, lupus-like syndrome, systemic lupus erythematosus and interstitial lung disease. Other autoimmune diseases associated with TNF-targeted therapies have been recently described, e.g. sarcoidosis, antiphospholipid syndrome-related features, and autoimmune hepatitis or uveitis. Large, prospective, postmarketing studies are required to evaluate the risk of developing autoimmune diseases in patients receiving TNF-targeted therapies.

Bacteria of the order Rhizobiales are able to establish nitrogen-fixing symbioses with legumes. Commonly, genes for symbiosis are harbored on large symbiotic plasmids. Although the transfer of symbiotic plasmids is commonly detected in nature, there are few experimentally characterized examples. In Rhizobium etli, the product of rctA inhibits the conjugation of the symbiotic plasmid by reducing the transcription of the virB operon. rctA is transcribed divergently from this operon, and its product is predicted to have a DNA binding domain. In the present study, using DNase I footprinting and binding assays, we demonstrated the specific binding of RctA to the virB operon promoter. A 9-bp motif in the spacer region of this promoter (the rctA binding motif box) and the presence of a functional -10 region were critical elements for RctA binding. Transcriptional fusion analyses revealed that the elimination of either element provoked a relief of RctA-mediated repression. These data support a model in which RctA inhibits the access of the RNA polymerase to the virB promoter. Interestingly, rctA expression levels were modulated by transcriptional interference from transcripts emanating from the virB promoter. This phenomenon adds another level of regulation for this system, thus revealing a novel mechanism of plasmid transfer regulation in the Rhizobiales.

There is little literature about the clinical presentation and time-course of postoperative venous thromboembolism (VTE) in different surgical procedures. RIETE is an ongoing, prospective registry of consecutive patients with objectively confirmed, symptomatic acute VTE. In this analysis, we analysed the baseline characteristics, thromboprophylaxis and therapeutic patterns, time-course, and three-month outcome of all patients with postoperative VTE. As of January 2006, there were 1,602 patients with postoperative VTE in RIETE: 393 (25%) after major orthopaedic surgery (145 elective hip arthroplasty, 126 knee arthroplasty, 122 hip fracture); 207 (13%) after cancer surgery; 1,002 (63%) after other procedures. The percentage of patients presenting with clinically overt pulmonary embolism (PE) (48%, 48%, and 50% respectively), the average time elapsed from surgery to VTE (22 +/- 16, 24 +/- 16, and 21 +/- 15 days, respectively), and the three-month incidence of fatal PE (1.3%, 1.4%, and 0.8%, respectively), fatal bleeding (0.8%, 1.0%, and 0.2%, respectively), or major bleeding (2.3%, 2.9%, and 2.8%, respectively) were similar in the three groups. However, the percentage of patients who had received thromboprophylaxis (96%, 76% and 52%, respectively), the duration of prophylaxis (17 +/- 9.6, 13 +/- 8.9, and 12 +/- 11 days, respectively) and the mean daily doses of low-molecular-weight heparin (4,252 +/- 1,016, 3,260 +/- 1,141, and 3,769 +/- 1,650 IU, respectively), were significantly lower in those undergoing cancer surgery or other procedures. In conclusion, the clinical presentation, time-course, and three-month outcome of VTE was similar among the different subgroups of patients, but the use of prophylaxis in patients undergoing cancer surgery or other procedures was suboptimal.

Background: The main cause of death in patients undergoing hemodialysis are cardiovascular events. We have analyzed the association between intradialysis fractional clearance of urea or Kt/V index in patients with chronic renal failure in hemodialysis as an indicator of adequate dialysis and the classical factors of cardiovascular risk., Patients and Methods: A total of 47 patients with chronic renal failure on hemodialysis were included. Diabetes mellitus was considered an exclusion criteria. Optimization of dialysis was analyzed by Kt/v index in accordance with the Daugirdas formula. The cardiovascular risk factors evaluated were: insulin resistance, calculated according to the HOMA method, total cholesterol, LDL-cholesterol, triglycerides, arterial hypertension, obesity and metabolic syndrome. The relationship between cardiovascular risk factors and Kt/V index was analyzed with the variant and multivariant analysis., Results: The HOMA median (interquartile range) of the patients was 1.16 (0.53-5.77). HOMA was correlated with triglycerides and HDL-cholesterol levels. HOMA was significantly greater in those who had less adapted dialysis (Kt/V < 1.4) (1.9 +/- 1.3 vs 1.0 +/- 0.3, p = 0.02). Furthermore, a negative correlation was found between HOMA and Kt/V. The multivariant analysis of the factors associated to HOMA demonstrated that the only associated parameters were Kt/V greater than 1.4, body mass index and age., Conclusions: In patients with chronic renal failure, adapted dialysis, determined by the Kt/V index, correlated negatively with insulin resistance. Based on these data, we suggest the need for longitudinal studies that consider this index as a predictive variable of cardiovascular events in this type of patients.

Berries and red fruits are important dietary sources of polyphenols [1]. In vitro and animal studies have demonstrated the bioavailability and the anti-proliferative and anticarcinogenic properties of these fruits or of their phenolic components [2, 3]. Consumption of berries may contribute to the reduction of colon cancer by mechanisms not yet understood. Gene expression analysis using microarrays allows for a more comprehensive study of the possible molecular mechanisms by which food or food components may prevent certain cancers of the gastrointestinal tract [4]. The aim of this research is to investigate the anti-proliferative effects of a polyphenol-rich berry juice on a human model of colon cancer cells and its association to transcriptional changes in relation to colon cancer.

Consumption of berries and red fruits rich in polyphenols may contribute to the reduction of colon cancer through mechanisms not yet understood. In this study, we investigated the response of subconfluent Caco-2 cells (a human colon carcinoma model) to repetitive exposure (2 h a day for a 4-day period) of a subtoxic dose of a chokeberry (Aronia melanocarpa) juice containing mixed polyphenols. To mimic physiological conditions, we subjected the chokeberry juice to in vitro gastric and pancreatic digestion. The effects on viability, proliferation and cell cycle were determined, and changes in the expression of genes in response to the chokeberry treatment were screened using Affymetrix oligonucleotide microarrays. Exposure to the chokeberry juice inhibited Caco-2 cell proliferation by causing G(2)/M cell cycle arrest. We detected changes in the expression of a group of genes involved in cell growth and proliferation and cell cycle regulation, as well as those associated to colorectal cancer. A selection of these genes was further confirmed by quantitative RT-PCR. Among these, the tumor suppressor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), whose expression is known to be reduced in the majority of early adenomas and carcinomas, was up-regulated by the treatment both at the mRNA and protein levels (as shown by flow cytometry analysis). CEACAM1, with a significant regulatory role on cell proliferation of particular interest at early stages of cancer development, may be a potential target for chemoprevention by food components such as those present in polyphenol-rich fruits.

A study was conducted to detect the presence of extended-spectrum beta-lactamases (ESBLs) in 706 isolates of Escherichia coli, largely from outpatients (75.2%). The Clinical and Laboratory Standards Institute (formerly NCCLS)-recommended disk diffusion procedure was used to detect ESBL presence; the VITEK 2 system (bioMérieux, Marcy L'Etoile, France) was used to determine the susceptibility to antibiotics of clinical interest, and the ESBLs were characterized by biochemical study, determining the isoelectric point, and by molecular study with PCR. Clonal distribution was studied in eight hospital isolates. There were 115 ESBL-producing isolates (16.3%), with a predominance of CTX-M9 type (58.3%). We draw attention to the high resistance to quinolones (>70%) in CTX-M9 and SHV enzyme producing isolates and the lower aminoglycoside activity in the latter.

Purpose: Studies have been done of the possibility that infection by human papillomavirus is a risk factor contributing to bladder cancer but no definite conclusions have yet been drawn. We performed a meta-analysis of observational studies published until July 2005 to ascertain the degree of association between bladder cancer and human papillomavirus infection., Materials and Methods: The MEDLINE database was searched using the key words bladder cancer and virus. Strict criteria were applied to select studies revealing the prevalence in serum of human papillomavirus infection or its direct detection in patients. A total of 44 articles with these methodological criteria were chosen., Results: In 39 studies the investigators determined the presence of human papillomavirus DNA, and found a prevalence of between 0% and 100% and significant homogeneity analysis (p <0.001). Pooled estimation of the presence of the infection was 16.0% (95% CI 12.8 to 19.1). Pooled OR estimation was 2.3 (95% CI 1.3 to 4.1) with no significant publication bias. In 7 studies human papillomavirus infection was studied by detecting the antigen or antibodies and a prevalence of between 14% and 60% was found with significant homogeneity analysis (p <0.001). Pooled estimation of the prevalence of infection was 32.4% (95% CI 17.0 to 47.8). Pooled OR estimation was 2.9 (95% CI 1.7 to 5.3)., Conclusions: Finding a relationship between bladder cancer and human papillomavirus depends on the method used. In the literature examined there are insufficient cases and samples compared to controls and studies rely on a combination of various microbiological techniques in the same patient and sample, making it difficult to draw any definite conclusion.

Plant-interacting micro-organisms can establish either mutualistic or pathogenic associations. Although the outcome is completely different, common molecular mechanisms that mediate communication between the interacting partners seem to be involved. Specifically, nitrogen-fixing bacterial symbionts of legume plants, collectively termed rhizobia, and phytopathogenic bacteria have adopted similar strategies and genetic traits to colonize, invade and establish a chronic infection in the plant host. Quorum-sensing signals and identical two-component regulatory systems are used by these bacteria to coordinate, in a cell density-dependent manner or in response to changing environmental conditions, the expression of important factors for host colonization and infection. The success of invasion and survival within the host also requires that rhizobia and pathogens suppress and/or overcome plant defence responses triggered after microbial recognition, a process in which surface polysaccharides, antioxidant systems, ethylene biosynthesis inhibitors and virulence genes are involved.

In this work, DNA microarrays were used to investigate genome-wide transcriptional responses of Sinorhizobium meliloti to a sudden increase in external osmolarity elicited by addition of either NaCl or sucrose to exponentially growing cultures. A time course of the response within the first 4 h after the osmotic shock was established. We found that there was a general redundancy in the differentially expressed genes after NaCl or sucrose addition. Both kinds of stress resulted in induction of a large number of genes having unknown functions and in repression of many genes coding for proteins with known functions. There was a strong replicon bias in the pattern of the osmotic stress response; whereas 64% of the upregulated genes had a plasmid localization, 85% of the downregulated genes were chromosomal. Among the pSymB osmoresponsive genes, 83% were upregulated, suggesting the importance of this plasmid for S. meliloti osmoadaptation. Indeed, we identified a 200-kb region in pSymB needed for adaptation to saline shock which has a high density of osmoregulated genes.

Background: Home treatment of patients with acute deep vein thrombosis (DVT) leads to cost savings and improved quality of life. However, little information is known about what influences the clinical outcome in these patients., Methods: The Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) is an ongoing registry of consecutive patients with symptomatic, objectively confirmed, acute DVT or pulmonary embolism (PE). In this analysis evaluated the clinical outcome

The exogenous addition of salicylic acid (SA) was previously shown to inhibit indeterminate but not determinate-type nodulation. We sought to extend these results by modulating endogenous levels of SA through the transgenic expression of salicylate hydroxylase (NahG) in both stably transformed Lotus japonicus and composite Medicago truncatula plants. NahG expression in L. japonicus resulted in a marked reduction of SA levels. This reduction correlated with an increase in the number of infections and mean nodule number when compared to controls. However, a complicating factor was that NahG-expressing plants had greater root growth. Spot inoculations of NahG-expressing L. japonicus plants confirmed increased nodulation in these plants. Consistent with the reported inhibitory effects of exogenous SA on indeterminate-type nodulation, NahG expression in M. truncatula plants led to enhanced nodulation and infection. These data point to an important role for SA-mediated plant defense pathways in controlling nodule formation on both determinate and indeterminate nodule-forming hosts.

Most orofacial infections are of odontogenic origin, and are of a self-limiting nature, characterized by spontaneous drainage. The causal bacteria are generally saprophytes. On the other hand, invasive dental interventions give rise to transient bacteremia. When an oral lesion is contaminated by extrinsic bacteria, the required antibiotic treatment should be provided as soon as possible. In the case of pulpitis, such treatment is usually not indicated if the infection only reaches the pulp tissue or the immediately adjacent tissues. In the event of dental avulsion, local antibiotic application is advised, in addition to the provision of systemic antibiotics. The dental professional must know the severity of the infection and the general condition of the child in order to decide referral to a medical center. Prophylaxis is required in all immunocompromised patients, as well as in individuals with cardiac problems associated with endocarditis, vascular catheters or prostheses. Penicillin V associated to clavulanic acid and administered via the oral route is known to be effective against odontogenic infections. In the case of allergies to penicillin, an alternative drug is clindamycin. Most acute infections are resolved within 3-7 days. In recent years, the tendency is to reduce general antibiotic use for preventive or therapeutic purposes.

Objective: To evaluate the influence of tumour quadrant localization on the sentinel node (SN) detection and the visualisation of internal mammary chain (IM) drainage by radioisotopic techniques. 316 patients with breast cancer were studied. Mean age 57 years (range 29-88). All patients received 37-74 MBq of 99mTc-albumin nanocolloid in 2 ml by peritumoral injection. The breast cancer was located in the upper outer quadrant in 189 patients, in the upper inner in 57, in the lower outer in 57, in the lower inner in 55 and in the subareolar area in 18 patients. At two hours p.i., anterior and lateral chest lymphographies were obtained. The SN location was marked on the patient skin with permanent ink. SN was identified intraoperatively by the gamma probe. Histopatological analysis included imprints, delayed hematoxilin-eosin, inmunohistochemistry CAM 19-2 and PCR., Results: The scintigraphy and surgical detection was in the upper outer quadrant of 90 % and 93 % respectively; in the lower outer quadrant of 91 % and 95 %, in the upper inner quadrant of 93 % and 95 %, in the lower inner quadrant 87 % and 95 % and in the subareolar area in 94 % and 83 %. The IM chain drainage was of 6 % in the UO, in the LO of 5 %, in the UI of 12 %, in the LI of 20 % and none in subareolar., Conclusions: Our data suggest that sentinel node location (quadrant) is not a influential factor in the scintigraphy and surgical detection. Tumours localised in internal quadrant show a higher rate of IM chain drainage.

The activity of different beta-lactam and non-beta-lactam antibiotics was assessed against extended-spectrum beta-lactamase (ESBL)-producing and non-ESBL-producing clinical isolates of Escherichia coli. A phenotypic study to discover the presence of ESBLs in 399 clinical isolates of E. coli was made by the disk diffusion method following the Clinical and Laboratory Standards Institute (formely NCCLS, 2004) guidelines. The activity of different antibiotics was subsequently studied using the automated VITEK 2 system (bioMérieux, Marcy l'Etoile, France). One hundred fifteen isolates proved to be ESBL-producing and 284 non-ESBL-producing. Among the former, percentage susceptibilities to the antibiotics assayed were meropenem and amikacin, 100%; piperacillin/tazobactam, 97.4%; cefepime, 94.8%; amoxicillin/clavulanic acid, 84.3%; tobramycin, 84.3%; gentamicin, 83.5%; cefoxitin, 83.5%; nitrofurantoin, 71.3%; cotrimoxazole, 46.1%; norfloxacin, 29.6%; ciprofloxacin, 27%; and ofloxacin, 26.1%.

A comparative study was conducted of a novel real-time quantitative PCR test (LightCycler System) with FastStart DNA Master(PLUS) SYBR Green I dye to detect DNA of human herpes virus 6 (HHV-6). Results were compared with those of a real-time quantitative PCR with hybridization probe (HP) formats using the fluorescence resonance energy transfer method, and with those of a single qualitative PCR test. The detection limit of the test with SYBR Green I dye was 20 copies of the virus, similar to that of the other two tests. The reproducibility was satisfactory. The new test has the same advantages as real-time PCR with HP formats and offers a greater versatility at lower cost.

An analysis of the conjugative transfer of pRetCFN42d, the symbiotic plasmid (pSym) of Rhizobium etli, has revealed a novel gene, rctA, as an essential element of a regulatory system for silencing the conjugative transfer of R. etli pSym by repressing the transcription of conjugal transfer genes in standard laboratory media. The rctA gene product lacks sequence conservation with other proteins of known function but may belong to the winged-helix DNA-binding subfamily of transcriptional regulators. Similar to that of many transcriptional repressors, rctA transcription seems to be positively autoregulated. rctA expression is greatly reduced upon overexpression of another gene, rctB, previously identified as a putative activator of R. etli pSym conjugal transfer. Thus, rctB seems to counteract the repressive action of rctA. rctA homologs are present in at least three other bacterial genomes within the order Rhizobiales, where they are invariably located adjacent to and divergently transcribed from putative virB-like operons. We show that similar to that of R. etli pSym, conjugative transfer of the 1.35-Mb symbiotic megaplasmid A of Sinorhizobium meliloti is also subjected to the inhibitory action of rctA. Our data provide strong evidence that the R. etli and S. meliloti pSym plasmids are indeed self-conjugative plasmids and that this property would only be expressed under optimal, as yet unknown conditions that entail inactivation of the rctA function. The rctA gene seems to represent novel but probably widespread regulatory systems controlling the transfer of conjugative elements within the order Rhizobiales.

Plant viruses in the genus Curtovirus (family Geminiviridae) are vectored by the beet leafhopper (Circulifer tenellus) and cause curly top disease in a wide range of dicotyledonous plants. An infectious clone of an isolate of Beet mild curly top virus (BMCTV-[W4]), associated with an outbreak of curly top in pepper and tomato crops, was characterized and used to investigate the role of the capsid protein (CP) in viral biology and pathogenesis. Frameshift mutations were introduced into the overlapping CP and V2 genes, and a series of CP alanine scanning mutations were generated. All mutants replicated in tobacco protoplasts or systemically infected plants, consistent with these gene products not being required for viral DNA replication. The CP frameshift mutant and most C-terminal alanine scanning mutants did not systemically infect Nicotiana benthamiana plants or form detectable virions, and were not leafhopper-transmitted. In contrast, most N-terminal alanine scanning mutants systemically infected N. benthamiana and induced disease symptoms, formed virions and were leafhopper-transmissible; thus, these substitution mutations did not significantly alter the functional properties of this region. One N-terminal mutant (CP49-51) systemically infected N. benthamiana, but did not form detectable virions; whereas another (CP25-28) systemically infected N. benthamiana and formed virions, but was not insect-transmissible. These mutants may reveal regions involved in virus movement through the plant and/or leafhopper vector. Together, these results indicate an important role for virions in systemic infection (long-distance movement) and insect transmission, and strongly suggest that virions are the form in which BMCTV moves, long distance, in the phloem.