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Lacticaseibacillus rhamnosus CRL1505 can be used in functional products as a probiotic powder (dried live cells) or as a postbiotic intracellular extract containing inorganic polyphosphate as a functional biopolymer. Thus, the aim of this work was to optimize the production of Lr-CRL1505 depending on the target of the functional product (probiotic or postbiotic). For this purpose, the effect of culture parameters (pH, growth phase) on cell viability, heat tolerance and polyphosphate accumulation by Lacticaseibacillus rhamnosus CRL1505 was evaluated. Fermentations at free pH produced less biomass (0.6 log units) than at controlled pH while the growth phase affected both polyphosphate accumulation and cell heat tolerance. Exponential phase cultures showed 4-15 times greater survival rate against heat shock and 49-62% increased polyphosphate level, compared with the stationary phase. Results obtained allowed setting the appropriate culture conditions for the production of this strain according to its potential application, i.e., as live probiotic cells in powder form or postbiotic. In the first case, running fermentations at pH 5.5 and harvesting the cells at the exponential phase are the best conditions for obtaining a high live biomass yield capable of overcoming heat stress. Whereas the postbiotic formulations production requires fermentations at free pH and harvesting the cells in exponential phase to increase the intracellular polyphosphate level as a first step.

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PURPOSE: Elevated mortality and morbidity rates persist in pediatric patients with medulloblastoma. We present a clinical audit of a real-world cohort of patients in search for pragmatic measures to improve their management and outcome. METHODS/PATIENTS: All pediatric patients with medulloblastoma treated between 2003 and 2016 at a Spanish reference center were reviewed. In the absence of internationally accepted quality indicators (QIs) for pediatric CNS tumors, diagnostic, therapeutic, survival, and time QIs were defined and assessed. RESULTS: Fifty-eight patients were included, 24% were younger children (< 3 years), 36% high risk (anaplastic, metastasis, or surgical residue > 1.5 cm2), and 40% standard risk. Five-year OS was 59.2% (95% CI 47-75); 5-year PFS 36.4% (95% CI 25-53). Five main areas of quality assurance were identified: diagnosis, global strategy, frontline treatment modalities, outcomes, and long-term and end-of-life care. A set of 34 QIs was developed and applied. Lack of central pathology review, delay in the incorporation of novel molecular markers, and absence of a neurocognitive and quality-of-life evaluation program were some of the audit findings. CONCLUSIONS: This real-world research study resulted in the development of a pragmatic set of QIs, aimed to improve clinical audits and quality of care given to children and adolescents with medulloblastoma. We hope that our findings will serve as a reference to further develop a quality assurance system with specific QIs for pediatric CNS tumors in the future and that this will ultimately improve the survival and quality of life of these patients.

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PURPOSE: To evaluate the prognostic factors associated with survival in patients treated with neoadjuvant treatment [chemoradiotherapy (CRT) or chemotherapy] followed by surgery (CRTS) in patients with stage IIIA-N2 non-small cell lung cancer (NSCLC). METHODS: A retrospective study was conducted of 118 patients diagnosed with stage T1-T3N2M0 NSCLC and treated with CRTS at 14 hospitals in Spain between January 2005 and December 2014. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method and compared using the log-rank test. Cox regression analysis was performed. RESULTS: Surgery consisted of lobectomy (74.5% of cases), pneumectomy (17.8%), or bilobectomy (7.6%). Neoadjuvant treatment was CRT in 62 patients (52.5%) and chemotherapy alone in 56 patients (47.5%). Median follow-up was 42.5 months (5-128 months). 5-year OS and PFS were 51.1% and 49.4%, respectively. The following variables were independently associated with worse OS and PFS: pneumonectomy (vs. lobectomy); advanced pathologic T stage (pT3 vs. pT0-pT2); and presence of persistent N2 disease (vs. ypN0-1) in the surgical specimen. CONCLUSIONS: In this sample of patients with stage IIIA-N2 NSCLC treated with CRTS, 5-year survival (both OS and PFS) was approximately 50%. After CRTS, the patients with the best prognosis were those whose primary tumour and/or mediastinal nodal metastases were downstaged after induction therapy and those who underwent lobectomy. These findings provide further support for neoadjuvant therapy followed by surgery in selected patients.

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Polyphosphate (polyP) degradation in Escherichia coli stationary phase triggers biofilm formation via the LuxS quorum sensing system. In media containing excess of phosphate (Pi), high polyP levels are maintained in the stationary phase with the consequent inhibition of biofilm formation. The transcriptional-response regulator PhoB, which is activated under Pi limitation, is involved in the inhibition of biofilm formation in several bacterial species. In the current study, we report, for the first time, we believe that E. coli PhoB can be activated in non-limiting Pi conditions, leading to inhibition of biofilm formation. In fact, PhoB was activated when high polyP levels were maintained in the stationary phase, whereas it remained inactive when the polymer was degraded or absent. PhoB activation was mediated by acetyl phosphate with the consequent repression of biofilm formation owing to the downregulation of c-di-GMP synthesis and the inhibition of autoinducer-2 production. These results allowed us to propose a model showing that PhoB is a component in the signal cascade regulating biofilm formation triggered by fluctuations of polyP levels in E. coli cells during stationary phase.

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K-12 Escherichia coli cells grown in static media containing a critical phosphate (Pi) concentration ≥25 mM maintained a high polyphosphate (polyP) level in stationary phase, impairing biofilm formation, a phenomenon that is triggered by polyP degradation. Pi concentration in human urine fluctuates according to health state. Here, the influence of environmental Pi concentration on the occurrence of virulence traits in uropathogenic E. coli (UPEC) isolated from acute prostatitis patients was evaluated. After a first screening, 3 isolates were selected according to differential biofilm formation profiles depending on media Pi concentration. For each isolate, biofilm positive and negative conditions were established. Regardless of the isolate, biofilm formation capacity was accompanied with curli and cellulose production and expression of some key virulence factors associated with adhesion. When the selected isolates were grown in their non-biofilm-forming condition, low concentrations of nalidixic acid and ciprofloxacin induced biofilm formation. Interestingly, similar to laboratory strains, polyP degradation induced biofilm formation in the selected isolates. Data demonstrated the complexity of UPEC responses to environmental Pi and the importance of polyP metabolism in the virulence of clinical isolates.

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The centromere appears as a single constriction at mitotic metaphase in most eukaryotic chromosomes. Holokinetic chromosomes are the exception to this rule because they do not show any centromeric constrictions. Holokinetic chromosomes are usually forgotten in most reviews about centromeres, despite their presence in a number of animal and plant species. They are generally linked to very intriguing and unusual mechanisms of mitosis and meiosis. Holokinetic chromosomes differ from monocentric chromosomes not only in the extension of the kinetochore plate, but also in many other peculiar karyological features, which could be understood as the 'holokinetic syndrome' that is reviewed in detail. Together with holokinetic chromosomes we review neocentromeric activity, a similarly intriguing case of regions able to pull chromosomes towards the poles without showing the main components reported to be essential to centromeric function. A neocentromere is a chromosomal region different from the true centromere in structure, DNA sequence and location, but is able to lead chromosomes to the cell poles in special circumstances. Neocentromeres have been reported in plants and animals showing different features. Both in humans and Drosophila, neocentric activity appears in somatic cells with defective chromosomes lacking a functional centromere. In most cases in plants, neocentromeres appear in chromosomes which have normal centromeres, but are active only during meiosis. Because of examples such as spontaneous or induced neocentromeres and holokinetic chromosomes, it is becoming less surprising that different structures and DNA sequences of centromeres appear in evolution.

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In the present work we report the phosphorylation pattern of histone H3 and the development of microtubular structures using immunostaining techniques, in mitosis of Rhynchospora tenuis (2n = 4), a Cyperaceae with holocentric chromosomes. The main features of the holocentric chromosomes of R. tenuis coincide with those of other species namely: the absence of primary constriction in prometaphase and metaphase, and the parallel separation of sister chromatids at anaphase. Additionaly, we observed a highly conserved chromosome positioning at anaphase and early telophase sister nuclei. Four microtubule arrangements were distinguished during the root tip cell cycle. Interphase cells showed a cortical microtubule arrangement that progressively forms the characteristic pre-prophase band. At prometaphase the microtubules were homogeneously distributed around the nuclear envelope. Metaphase cells displayed the spindle arrangement with kinetochore microtubules attached throughout the entire chromosome extension. At anaphase kinetochoric microtubules become progressively shorter, whereas bundles of interzonal microtubules became increasingly broader and denser. At late telophase the microtubules were observed equatorially extended beyond the sister nuclei and reaching the cell wall. Immunolabelling with an antibody against phosphorylated histone H3 revealed the four chromosomes labelled throughout their entire extension at metaphase and anaphase. Apparently, the holocentric chromosomes of R. tenuis function as an extended centromeric region both in terms of cohesion and H3 phosphorylation.

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The recent interest in the conservation of the tropical forest is due, at least in part, to the potential economic and health benefits that can be exploited from several plants. This report shows the in vitro antioxidant activity of some fractions isolated from leaves of two Columbian Magnoliaceae, Talauma hernandezii G. Lozano-C and Dugandiodendron yarumalense Lozano. The activity was determined using the radical monocation 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS.+) and the stable free radical 2-2-diphenyl-1-picrylhydrazyl (DPPH.), as part of general biological screening of these plants. The antioxidant capacity obtained from fractions was similar to those of alpha-tocopherol, tert-butylated hydroxyanisole (BHA), and ascorbic acid. The most active scavenger extract was the fraction 7 (TAA = 48.6 mmol Trolox/kg extract and IC50 < or = 0.01 kg extract/mmol DPPH); and the least active was the fraction 1 (TAA = 11.23 mmol Trolox/kg extract and IC50 = 0.21 kg extract/mmol DPPH) all of them isolated from D. yarumalense. These results suggest that these plants can be attractive as source of antioxidant compounds with the ability to reduce radicals like ATBS and DPPH.

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To evaluate the mitotic stability of Triticum aestivum x Thinopyrum ponticum derivatives (BC(2)F(7) and BC(2)F(5) doubled haploids), chromosome counting by both conventional and immunostaining techniques, and measurement of DNA content were performed. The wheat progenitor line, PF 839197, the wheat recurrent parent CEP 19 and the control Chinese Spring were also investigated. In the hybrid derivatives, chromosome number ranged from 2n=36 to 60, with a predominance of chromosome numbers higher than 2n=42, that was confirmed by determination of nuclear DNA content. Chinese Spring' and PF 839197 were stable, but CEP 19 showed chromosome number variation (20%). Analyses of non-pretreated cells revealed the presence of anaphase bridges, lagging chromatids, chromosome fragments and micronuclei. Immunostaining with an antibody recognizing histone H3 phosphorylated showed dicentric chromatids forming anaphase bridges and pericentromeric phosphorylation at centric chromosome fragments but not at lagging chromatids. The possible causes of the observed mitotic instability are discussed.

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In previous work, genotypes for high and low B chromosome transmission rate were selected from a native race of maize. It was demonstrated that the B transmission is genetically controlled. The present work reports the fourth and fifth generations of selection and the F1 hybrids between the lines. The native B is characterized by a constant behaviour, with normal meiosis and nondisjunction in 100% of postmeiotic mitosis. It is concluded that genetic variation for B transmission between the selected lines is due to the preferential fertilization process. The F1 hybrids show intermediate B transmission rate between the lines. They are uniform, the variance of the selected character being one order of magnitude lower than that of the native population. In addition, 0B x 2B and 2B x 2B crosses were made to study the effect of the presence of B chromosomes in the female parent, resulting in non-significant differences. Several crosses were made both in Buenos Aires and in Madrid to compare the possible environmental effect, but significant differences were not found. Our results are consistent with the hypothesis of a single major gene controlling B transmission rate in maize, which acts in the egg cell at the haploid level during fertilization. It is also hypothesized that maize Bs use the normal maize fertilization process to promote their own transmission.

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We have used a fast, sensitive and efficient method for the analysis of volatile carbonyl compounds (saturated aliphatic and unsaturated aldehydes) based on solid-phase microextraction with on-fibre derivatisation. Pentafluorophenylhydrazine was absorbed onto a poly(dimethylsiloxane)/divinylbenzene-coated fibre and exposed to the vapours of aldehyde-containing matrices. The hydrazones formed on the fibre were desorbed into the gas chromatograph injection port and quantified by means of electron-capture detection with high sensitivity (10-90 fmol) and good reproducibility (RSD<10%). The method was applied to the headspace-sampling of volatile carbonyl compounds released during the thermally-induced degradation of sunflower oil.

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BACKGROUND: Until very recently, interferon (INF) in Spain was authorized in chronic hepatitis C (C-HCV) at a dosis of 3 megaunits (mu) for 6 months. Nonetheless, the rate of maintained complete response is lower than that obtained with more prolonged treatments. The first aim of this study was to retrospectively know the effectiveness of alpha INF in patients treated for 6 or 12 months with a dosis of 3 or 5-6 MU. The second was to analyze the characteristics of the patients who achieved a maintained complete response. PATIENTS AND METHODS: Patients with C-HCV treated in 9 hospitals in Andalucía, Spain who fulfilled the following conditions were retrospectively analyzed: liver biopsy prior to treatment, positive test for anti HCV and a follow up of at least 6 months after alpha INF treatment. A total of 344 patients were studied: 267 treated with alpha INF-2b, 51 with alpha INF-2a and 26 with lymphoblastoid INF. One hundred ninety-five patients were treated for 6 months and 149 for 12 months. RESULTS: Seventy-seven (22%) of the patients presented maintained complete response, 170 (50%) did not respond and 97 (28%) relapsed. On comparing the three types of interferon used over 6 months, no significant differences were observed. Neither were differences found on comparing the dosis of 3 mu versus 5 or 6 mu. On analyzing the treatments of 6 and 12 months, the following was observed, respectively: maintained complete response 15% vs 32%, relapse 29% vs 30% and non responders 57% vs 38% (p < 0.001). Multivariate analysis demonstrated that the patients who responded the best to INF were those who presented the following characteristics: female sex, age under 40 years last, history of transfusion or IVDA, basal GPT level higher than 145 IU/I, GGT less than 55 IU/I, less evolved histologic lesions and duration of treatment over 12 months. CONCLUSIONS: Of the different treatments analyzed with alpha interferon in chronic hepatitis C, the best was found to be that with 3 mu during 12 months.

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One hundred and twenty-two strains of Pseudomonas isolated from diverse pathological processes were typified. In vitro activity of Piperacillin (antibiogram and MIC) was studied and compared with another two semisynthetic penicillins, Carbenicillin and Mezlocillin, and two aminoglycosides, Amikacin and Gentamicin. The strains isolated corresponded to: Pseudomonas aeruginosa (116), Pseudomonas cepacia (3), Pseudomonas fluorescens (1) and Pseudomonas putida (1). It was found that 110 Pseudomonas aeruginosa, one Pseudomonas cepacia and one Pseudomonas fluorescens were susceptible to Piperacillin. The susceptibility to this drug was quite higher than to the other penicillins tested. The MIC50 and MIC90 of Piperacillin were lower than those of semisynthetic penicillins and the minimum susceptibility value. In comparison with aminoglycosides it was found that, although Amikacin and Gentamicin did not reach the minimum value, Piperacillin exhibited higher MICs.

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One hundred and twenty-two strains of Pseudomonas isolated from diverse pathological processes were typified. In vitro activity of Piperacillin (antibiogram and MIC) was studied and compared with another two semisynthetic penicillins, Carbenicillin and Mezlocillin, and two aminoglycosides, Amikacin and Gentamicin. The strains isolated corresponded to: Pseudomonas aeruginosa (116), Pseudomonas cepacia (3), Pseudomonas fluorescens (1) and Pseudomonas putida (1). It was found that 110 Pseudomonas aeruginosa, one Pseudomonas cepacia and one Pseudomonas fluorescens were susceptible to Piperacillin. The susceptibility to this drug was quite higher than to the other penicillins tested. The MIC50 and MIC90 of Piperacillin were lower than those of semisynthetic penicillins and the minimum susceptibility value. In comparison with aminoglycosides it was found that, although Amikacin and Gentamicin did not reach the minimum value, Piperacillin exhibited higher MICs.

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By inoculation to the chorio-allantoic membrane of material from different types of human leprosy, macroscopically visible nodular lesions are obtained. These lesion have been reinoculated in the chorio-allantoic membrane and the lesion were thus reproduced by serial passage. Histologically, theses lesions are similar to a leproid granuloma, including foamy cells, within them no acid-fast particles can be observed until the sixth passage on. The filtrate through Mendel pore filter of lesion from the fourth passage of lepromatous leproma material gave also lesion macroscopically and microscopically similar to those obtained from direct human leprous material...

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