Showing papers by "University of Barcelona published in 1996"
TL;DR: It is proposed that these effects are manifestations of thermally assisted, field-tuned resonant tunneling between quantum spin states, and attribute the observation of quantum-mechanical phenomena on a macroscopic scale to tunneling in a large (Avogadro's) number of magnetically identical molecules.
Abstract: We report the observation of steps at regular intervals of magnetic field in the hysteresis loop of a macroscopic sample of oriented M${\mathrm{n}}_{12}$${\mathrm{O}}_{12}$(C${\mathrm{H}}_{3}$COO${)}_{16}$(${\mathrm{H}}_{2}$O${)}_{4}$ crystals. The magnetic relaxation rate increases substantially when the field is tuned to a step. We propose that these effects are manifestations of thermally assisted, field-tuned resonant tunneling between quantum spin states, and attribute the observation of quantum-mechanical phenomena on a macroscopic scale to tunneling in a large (Avogadro's) number of magnetically identical molecules.
1,354 citations
TL;DR: Cirrhotics with increased portal pressure are at high risk of hepatic decompensation after resection of hepatocellular carcinoma, and surgical resection should therefore be restricted to patients without portal hypertension.
831 citations
TL;DR: The results indicated that the predictive accuracy of the programs analyzed was lower than originally found, which indicates that the programs are overly dependent on the particularities of the examples they learn from.
749 citations
TL;DR: A global pattern of haplotype variation and linkage disequilibrium suggests a common and recent African origin for all non-African human populations.
Abstract: Haplotypes consisting of alleles at a short tandem repeat polymorphism (STRP) and an Alu deletion polymorphism at the CD4 locus on chromosome 12 were analyzed in more than 1600 individuals sampled from 42 geographically dispersed populations (13 African, 2 Middle Eastern, 7 European, 9 Asian, 3 Pacific, and 8 Amerindian). Sub-Saharan African populations had more haplotypes and exhibited more variability in frequencies of haplotypes than the Northeast African or non-African populations. The Alu deletion was nearly always associated with a single STRP allele in non-African and Northeast African populations but was associated with a wide range of STRP alleles in the sub-Saharan African populations. This global pattern of haplotype variation and linkage disequilibrium suggests a common and recent African origin for all non-African human populations.
576 citations
TL;DR: The results obtained represent the first molecular evidence for a Tardigrada + Arthropoda clade and indicate the need to review those obtained solely on morphological characters.
Abstract: The complete 18S rDNA gene sequence of Macrobiotus group hufelandi (Tardigrada) was obtained and aligned with 18S rDNA and rRNA gene sequences of 24 metazoans (mainly protostomes) Discrete character (maximum-parsimony) and distance (neighbor-joining) methods were used to infer their phylogeny The evolution of bootstrap proportions with sequence length (pattern of resolved nodes, PRN) was studied to test the resolution of the nodes in neighbor-joining trees The results show that arthropods are monophyletic Tardigrades represent the sister group of arthropods (in parsimony analyses) or they are related with crustaceans (distance analysis and PRN) Arthropoda are divided into two main evolutionary lines, the Hexapoda + Crustacea line (weakly supported), and the Myriapoda + Chelicerata line The Hexapoda + Crustacea line includes Pentastomida, but the internal resolution is far from clear The Insecta (Ectognatha) are monophyletic, but no evidence for the monophyly of Hexapoda is found The Chelicerata are a monophyletic group and the Myriapoda cluster close to Arachnida Overall, the results obtained represent the first molecular evidence for a Tardigrada + Arthropoda clade In addition, the congruence between molecular phylogenies of the Arthropoda from other authors and this obtained here indicates the need to review those obtained solely on morphological characters
529 citations
TL;DR: Theoretical models and ab initio Hartree−Fock wave functions are used to investigate the N 1s core level binding energies of N-containing calcined carbonaceous materials.
Abstract: Theoretical models and ab initio Hartree−Fock wave functions are used to investigate the N 1s core level binding energies of N-containing calcined carbonaceous materials. Comparison of calculated and experimental values for a series of test molecules reveals that the N 1s core level shift from one compound to another is mainly originated by initial state effects. This permits a systematic study of different situations and allows establishment that three different types of nonoxidized N atoms can be present in these materials. These are “pyridinic”, “pyrrolic”, and “graphitic” nitrogen with binding energies of ≈399.0, ≈400.3, and ≈401−403 eV, respectively. This assignment is in very good agreement with a recent experimental X-ray photoelectron spectra on petroleum cokes and demonstrates, for the first time, that it is possible for N to exhibit rather large core level 1s energies without requiring the presence of any charge transfer from N-oxide groups. Theoretical reasons for such a behavior are also given.
478 citations
TL;DR: It is suggested that the simultaneous duplication of many classes of genes, often interacting in gene networks, allowed the elaboration of new developmental control mechanisms at vertebrate origins.
424 citations
TL;DR: The multivariate analysis showed that patients had a worse prognosis if they were previously bedridden, had prior swallowing disorders, body temperature on admission was less than 37 degrees C, respiratory frequency was greater than 30/min or had three or more affected lobes on chest radiograph.
Abstract: To assess the risk and prognostic factors of community-acquired pneumonia occurring in the elderly (over age 65 yr) requiring hospitalization, two studies, case-control and cohort, were performed over an 8-mo period in a 1,000-bed university teaching hospital. We studied 101 patients with pneumonia (cases), age 78.5 +/- 7.9 yr (mean +/- SD). Each case was matched for sex, age (+/- 5 yr), and date of admission (+/- 2 d) with a control subject, without pneumonia during the preceding 3 yr, arriving at the emergency room. Etiologic diagnosis was obtained in 43 of 101 (42%) cases. The main microbial agents causing pneumonia were: Streptococcus pneumoniae (19 of 43, 44%), and Chlamydia pneumoniae (9 of 43, 21%). Gram-negative bacilli were uncommon (2 of 43, 5%). The multivariate analysis demonstrated that large-volume aspiration, and low serum albumin (< 30 mg/dl) were independent risk factors associated with the development of pneumonia. Crude mortality rate was 26% (26 of 101), while pneumonia-related mortality was 20% (20 of 101). The attributable mortality was 23% (odds ratio [OR]: 11.3; 95% confidence interval [CI]: 3.25 to 60.23; p < 0.0001). The multivariate analysis showed that patients had a worse prognosis if they were previously bedridden, had prior swallowing disorders, body temperature on admission was less than 37 degrees C, respiratory frequency was greater than 30/min or had three or more affected lobes on chest radiograph. Age by itself was not a significant factor related to prognosis. Among the significant risk factors, only nutritional status is probably amenable to medical intervention. The prognostic factors found in this study may help to identify, upon admission, those subjects at higher risk and who may require special observation.
321 citations
TL;DR: In this article, the authors propose guidelines that make it more likely that high quality information is reliably extracted and coded from primary research reports, addressing issues ranging from the selection of items and construction of coding materials to sustaining reliability and vigilance across extended periods of coding.
Abstract: In meta-analyses the extraction and coding of information from primary research reports has to be completed in a competent way because these tasks implicate most of the decisions that determine the usefulness of the final product. The authors offer guidelines that make it more likely that high-quality information is reliably extracted and coded from primary research reports. These guidelines address issues ranging from the selection of items and construction of coding materials to sustaining reliability and vigilance across extended periods of coding. Thereafter, the authors note how the methodology of meta-analysis results in pressure to change the type of information that appears in primary research reports, and close by offering a few conjectures about the future of meta-analysis.
311 citations
TL;DR: In this paper, a complete and accurate picture of tautomerism and protonation of nucleic acid bases has been provided by using high level ab initio calculations with inclusion of correlation effects at the Moller−Plesset level.
Abstract: Tautomerism and protonation of guanine and cytosine in the gas phase and in aqueous solution have been examined by theoretical methods. High level ab initio calculations with inclusion of correlation effects at the Moller−Plesset level have been used to study these processes in the gas phase. The influence of solvent has been examined using self-consistent reaction field and Monte Carlo free energy perturbation simulations. The results provide a complete and accurate picture of tautomerism and protonation of these nucleic acid bases. Comparison with the available experimental data gives confidence in the quality of the results derived from theoretical computations. Inspection of the most stable tautomeric forms for the neutral and protonated nucleic acid bases allows rationalization of the formation of unusual DNA structures like the triple helix.
308 citations
TL;DR: It is indicated that p53 gene mutations are an infrequent phenomenon in MCLs and are associated with a subset of aggressive variants.
TL;DR: The authors find that OS deserve much more attention than cholesterol itself in terms of research activity but that unfortunately the reverse is true with regard to funding.
TL;DR: In this article, the authors determined the relevance of nasal carriage of Staphylococcus aureus, either methicillin-sensitive (MSSA) or methically-resistant (MRSA), as a risk factor for the development of nosocomial S auresus bacteremia during an MRSA outbreak.
TL;DR: In patients with COPD, in whom hypoxaemia is caused essentially by V(A)/Q imbalance rather than by shunt, inhaled NO can worsen gas exchange because of impaired hypoxic regulation of the matching between ventilation and perfusion.
TL;DR: Results of HLA-identical sibling bone marrow transplantation for CLL in 54 patients who were younger than 60 years old are analyzed, finding indications varied from consolidation of a good response to chemotherapy, poor response to conventional-dose therapy, or young age.
Abstract: Objective: To characterize in detail the outcomes of HLA-identical sibling bone marrow transplantation for chronic lymphocytic leukemia (CLL) in patients younger than 60 years of age. Design: Retro...
TL;DR: A high prevalence (45-50%) of endometriosis (including microscopic forms) is shown in both patients with chronic pelvic pain and asymptomatic women (fertile and infertile), thus supporting the modern concept that in many women endometRIosis may be a paraphysiological condition.
Abstract: In 100 consecutive patients who were undergoing laparoscopy for infertility (group 1, n = 52), chronic pelvic pain (group 2, n = 18) or tubal sterilization (group 3, n = 30, asymptomatic fertile women), peritoneal biopsies were taken from areas of visually normal peritoneum of uterosacral ligaments. Twenty-six patients in group 1 (50%), eight patients in group 2 (44.4%) and 13 patients in group 3 (43.3%), were found to have laparoscopic evidence of endometriosis elsewhere in the pelvis. The majority of women (80.7% in group 1, 87.5% in group 2, and 100% in group 3) had stage I disease. The incidence of the distinctive appearances of the lesions was similar in the three groups of patients and 7% of all women or 15% (7/47) of those patients having endometriosis at laparoscopy had only subtle (non-?typical') endometriotic peritoneal lesions. Uterosacral biopsies showed the presence of endometriotic tissue in three cases (5.7%), two cases (11%) and three cases (10%) in groups 1, 2, and 3 respectively. One of the two patients in group 2 and two of the three patients in group 3 had no evidence of endometriosis at laparoscopy; thus histological study revealed the presence of endometriosis in normal peritoneum in 11% (5/47) of patients having macroscopic endometriosis and in 6% (3/53) of patients without endometriosis at laparoscopy. Previous oral contraceptive users were significantly higher among women having macroscopic and/or microscopic endometriosis than among women without the condition. In conclusion, our prospective study shows a high prevalence (45-50%) of endometriosis (including microscopic forms) in both patients with chronic pelvic pain and asymptomatic women (fertile and infertile), thus supporting the modern concept that in many women endometriosis may be a paraphysiological condition while probably only in some patients small amounts of endometriosis are an ?annoyance' with implications to their reproductive health and may produce symptoms (e.g. pelvic pain) and therefore should be defined as a ?dis-ease'. Previous use of oral contraceptives may increase the risk of developing endometriosis.
TL;DR: Identification of prognostic factors may help in the selection of the appropriate treatment for these patients with HCC and cirrhosis who underwent liver resections.
Abstract: Objective The authors analyze the outcomes of patients with hepatocellular carcinoma (HCC) and cirrhosis who underwent liver resections. Background Liver resection is the best option for HCC arising from hepatic cirrhosis. The experience of Western centers with these patients is shorter than the Asian series. Methods Forty-eight consecutive patients with cirrhosis and HCC who underwent liver resections were studied after a similar diagnostic and therapeutic process. Survival and cumulative recurrence were calculated according to pathologic findings. Results Factors influencing survival at 3 years were as follows: type of resection, absence of vascular invasion, size of the tumor, absence of satellite nodules, and the number of nodules. Factors influencing the rate of recurrence at 3 years were the presence of vascular invasion and the presence of satellite nodules. Patients with favorable prognostic factors have a good survival rate with an acceptable recurrence rate. Conclusions Identification of prognostic factors may help in the selection of the appropriate treatment for these patients with HCC and cirrhosis.
TL;DR: The timing of divergence of populations within Iberia points to a shared ancestry of all populations in the Upper Palaeolithic, and lineage diversity comparisons with European and North African populations shows the Iberian Peninsula to be more similar to other European populations, although a small number of Iberians lineages can be traced to North Africa.
Abstract: We have analysed 302 bp of the first hypervariable region of the mitochondrial D-loop in 271 individuals from different regions of the Iberian Peninsula and 85 individuals from Algeria. The Basque population is significantly different from neighbouring populations in terms of overall levels of diversity. This is because the majority of sequences in the Basques are restricted to the lineage group defined by the CRS (Cambridge Reference Sequence) and its derivatives although, like other Iberian populations, they showed a unimodal distribution of pairwise sequence differences. The timing of divergence of populations within Iberia points to a shared ancestry of all populations in the Upper Palaeolithic. Further genetic subdivision is apparent in Catalonia and Andalusia, with increased genetic diversity in the latter. Lineage diversity comparisons of Iberian populations with European (Tuscan) and North African (Algerian) populations shows the Iberian Peninsula to be more similar to other European populations, although a small number of Iberian lineages can be traced to North Africa.
TL;DR: It is suggested that ParC from E. coli may be another target for quinolones and that mutations at residues Ser-80 and Glu-84 may contribute to decreased fluoroquinolone susceptibility.
Abstract: The gene parC encodes the A subunit of topoisomerase IV of Escherichia coli. Mutations in the parC region analogous to those in the quinolone resistance-determining region of gyrA were investigated in 27 clinical isolates of E. coli for which ciprofloxacin MICs were 0.0007 to 128 micrograms/ml. Of 15 isolates for which ciprofloxacin MICs were > or = 1 microgram/ml, 8 showed a change in the serine residue at position 80 (Ser-80), 4 showed a change in Glu-84, and 3 showed changes in both amino acids. No mutations were detected in 12 clinical isolates for which ciprofloxacin MICs were < or = 0.25 micrograms/ml. These findings suggest that ParC from E. coli may be another target for quinolones and that mutations at residues Ser-80 and Glu-84 may contribute to decreased fluoroquinolone susceptibility.
TL;DR: In this paper, the relationship between the photochemical reflectance index (PRI) derived from this signal, and photosynthetic radiation-use efficiency (defined as net CO 2 assimilation rate/incident photon flux density) in a cereal canopy was studied.
Abstract: Some processes of excess radiation dissipation have been associated with changes in leaf reflectance near 531 nm. We aimed to study the relations between the photochemical reflectance index (PRI) derived from this signal, and photosynthetic radiation-use efficiency (defined as net CO 2 assimilation rate/incident photon flux density) in a cereal canopy. Measurements of reflectance, fluorescence, gas exchange and xanthophyll cycle pigments were made in the morning, midday and afternoon in barley canopies with two levels of nitrogen fertilization. The photosynthetic radiation-use efficiency decreased at midday, mainly in the third leaf, in both treatments, with lower values for the nitrogen deficient leaves. The zeaxanthin content showed the inverse pattern, increasing at midday and in the nitrogen deficient treatment. The photosynthetic radiation-use efficiency was well correlated with the epoxidation state, EPS (violaxanthin + 0.5 antheraxanthin)/(violaxanthin + antheraxanthin + zeaxanthin). The PRI [here defined as (R 539 - R 570 )/(R 539 + R 570 )] was significantly correlated with epoxidation state and zeaxanthin and with photosynthetic radiation-use efficiency. These results validate the utility of PRI in the assessment of radiation-use efficiency at canopy level.
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02 Oct 1996TL;DR: This monograph develops a very general approach to the algebra- ization of sententiallogics, to show its results on a number of particular logics, and to relate it to other existing approaches, namely to those based on logical matrices and the equational consequence developed by Blok, Czelakowski, Pigozzi and others.
Abstract: The purpose of this monograph is to develop a very general approach to the algebra- ization of sententiallogics, to show its results on a number of particular logics, and to relate it to other existing approaches, namely to those based on logical matrices and the equational consequence developed by Blok, Czelakowski, Pigozzi and others. The main distinctive feature of our approachlies in the mathematical objects used as models of a sententiallogic: We use abstract logics, while the dassical approaches use logical matrices. Using models with more structure allows us to reflect in them the metalogical properties of the sentential logic. Since an abstract logic can be viewed as a "bundle" or family of matrices, one might think that the new models are essentially equivalent to the old ones; but we believe, after an overall appreciation of the work done in this area, that it is precisely the treatment of an abstract logic as a single object that gives rise to a useful -and beautiful- mathematical theory, able to explain the connections, not only at the logical Ievel but at the metalogical Ievel, between a sentential logic and the particular dass of models we associate with it, namely the dass of its full models. Traditionally logical matrices have been regarded as the most suitable notion of model in the algebraic studies of sentential logics; and indeed this notion gives sev- eral completeness theorems and has generated an interesting mathematical theory.
TL;DR: In this article, the pKa of an acid and the pH of a buffered solution at any methanol−water composition were derived based on the preferential solvation of the solute by the three solvents that coexist in the mixture.
Abstract: Several properties of methanol−water mixtures (molar volume, molar refractivity, Debye−Huckel parameters, pH scale, HPLC-useful pH range, dissociation constants of acids) are studied. Some macroscopic properties are used to calculate the extent of the methanol−water interaction. Solute properties, such as pKa values, depend on the preferential solvation of the solute by the three solvents that coexist in the mixture (methanol, water, methanol−water aggregrates). Based on this preferential solvation and on the methanol−water interaction, equations that relate the pKa values of acids with the solvent composition are derived. The equations are applied to several acids widely used to prepare HPLC buffers. The pKa of an acid and the pH of a buffered solution at any methanol−water composition can be easily calculated from the proposed equations. The chromatographic retention of any solute can be thus related to the real pH value of the mobile phase used. This procedure is more rigorous and should give better re...
TL;DR: In this study, LASIK resulted in insignificant corneal scarring, stable refractive correction over six months, no irregular astigmatism, and excellent visual acuity.
Abstract: BACKGROUND: Laser in situ keratomileusis (LASIK) combines a lamellar corneal flap with an excimer laser ablation in the stromal bed to correct a wide range of myopia. We reviewed 43 eyes treated with LASIK to correct -7.00 to -18.50 diopters (D). METHOD: The data from 43 consecutive eyes of 30 patients aged 24 to 46 years were analyzed. Surgery was performed under topical anesthesia using the Chiron Automated Corneal Shaper and Keracor 116 Excimer laser with the multizone mode and our modified nomogram. Manifest and cycloplegic refraction, uncorrected visual acuity, spectacle corrected visual acuity, videokeratography, endothelial cell count, slit-lamp microscopy, fundus examination, and applanation tonometry were recorded preoperatively and at 1 week and 1, 3, and 6 months, postoperatively. RESULTS: We divided the eyes into two groups. The lower myopia group had a mean preoperative spherical equivalent refraction of -9.30 +/- 1.31 D (range: -7.00 D to -12.00 D) and mean postoperative refraction of -0.80 +/- 0.79 (range: -0.25 D to -3.50 D). The mean spectacle corrected visual acuity preoperatively was 0.74 +/- 0.20 and postoperatively was 0.74 +/- 0.18. The higher myopia group had a mean preoperative spherical equivalent refraction of -14.86 +/- 1.87 D (range: -12.25 D to -18.50 D) and a mean postoperative refraction of -1.80 +/- 1.29 D (range -1.00 D to -5.25 D). The mean spectacle corrected visual acuity preoperatively was 0.50 +/- 0.19 and postoperatively was 0.51 +/- 0.18. No overcorrections occurred in either group. One eye of the higher group lost one line of spectacle corrected visual acuity. No eye had visually significant corneal haze. The mean change in spherical equivalent refraction between preoperatively and 6 months postoperatively was 8.50 D for the lower myopia group and 13.06 D for the higher myopia group, in the myopic direction. Visual rehabilitation was rapid after surgery. CONCLUSIONS: In this study, LASIK resulted in insignificant corneal scarring, stable refractive correction over six months, no irregular astigmatism, and excellent visual acuity. Predictability was more accurate up to -12.00 D of intended correction.
TL;DR: The Dumon stent (or Endoxane), designed in 1987, is a flexible, multisized, studded, silicone prosthesis.
Abstract: SummaryThe Dumon stent (or Endoxane), designed in 1987, is a flexible, multisized, studded, silicone prosthesis. This report describes the combined results of Dumon stent placement in Marseille, France (J.F.D.), Brescia, Italy (S.C.), Saint-Etienne, France (J.M.V.), and Barcelona, Spain (P.O.). The
TL;DR: Data indicate that whereas phosphatidylinositol 3-kinase is not indispensable for cell proliferation or in the initial events of myoblast differentiation, it appears to be essential for terminal differentiation of muscle cells.
TL;DR: In this paper, the existence of resonant spin tunnelling between degenerate excited levels of opposite spin orientation was inferred from magnetic-field values Bn = nB1, where B1? 5 kG.
Abstract: Zero-field?cooled magnetization, magnetic relaxation, and a.c. susceptibility measurements have been performed on a Mn12-Ac oriented powdered sample as a function of temperature, field, and orientation. Magnetization jumps and susceptibility peaks have been observed about magnetic-field values Bn = nB1, where B1 ? 5 kG. These anomalies are due to the existence of relaxation rate maxima near Bn. From these experimental results we infer the existence of resonant spin tunnelling between degenerate excited levels of opposite spin orientation.
TL;DR: The detection of circulating melanoma cells in peripheral blood by RT-PCR correlated with the clinical stage of patients with melanoma and was an independent prognostic factor for recurrence in patients with nonmetastatic disease.
Abstract: PURPOSECirculating melanoma cells can be detected in peripheral blood by means of tyrosinase mRNA amplification by reverse-transcriptase polymerase chain reaction (RT-PCR). We conducted a prospective study to evaluate the clinical significance of the presence of circulating neoplastic cells in the blood of patients with malignant melanoma (MM).METHODSA sensitive RT-PCR assay was used to detect tyrosinase mRNA in the peripheral blood of patients with stages I to IV melanoma. Healthy subjects or patients with other malignancies were used as negative controls.RESULTSNinety-one assessable patients were included in the study. There was a statistically significant association between RT-PCR positivity and clinical stage. Circulating melanoma cells were detected in 36% of patients with localized disease (stages I and II), in 45% of patients with regional nodal involvement (stage III), and in 94% of patients with metastatic disease (stage IV) (P < .001). In stage II-III patients who were RT-PCR-positive for mRNA ...
TL;DR: In this article, structural and morphological analysis of nanocrystalline SnO2 for gas sensor applications were performed at different annealing conditions by using nanopowders and thin nanocrystine layers, and the evolution of the grain size and the morphology of Pt doped tin dioxide nanoparticles with increase of annaling temperature from 450 to 1000°C were analyzed by means of transmission electron microscopy, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) and micro-Raman spectroscopies.
Abstract: Structural and morphological analysis of nanocrystalline SnO2 for gas sensor applications were performed at different annealing conditions by using nanopowders and thin nanocrystalline layers. The evolution of the grain size and the morphology of Pt doped tin dioxide nanoparticles with increase of annealing temperature from 450 to 1000°C were analyzed by means of transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) and micro-Raman spectroscopies. TEM shows that the average particle size increases, the size distribution becomes more spread out, and the grain faceting, as a mechanism of energy minimization, is more evident with increasing temperature. Furthermore, the shape of the particles changes with the annealing temperature, which explains the results of the FTIR spectra using the Theory of the Average Dielectric Constant (TADC). As temperature increases, the Raman spectra are modified in agreement with a reduction of the crystalline defect concentration and a grain size increase. The the tin nanocrystalline SnO2 layers, deposited on α-Al2O3 or on thermally oxidezed Si substrates, have been annealed at 700° C for 8 h under different atmospheres, such as oxygen or synthetic air. TEM proves that the annealing atmosphere has a strong influence on the size and size distribution of the nanoparticles in the thin layer. The main differences are found near the layer-substrate interface and are dependent on the annealing atmosphere as well as the nature of the substrate.
TL;DR: Results indicate that B.trimera shows strong anti-inflammatory and analgesic properties which seem to be due, at least partly, to the inhibition of prostaglandin biosynthesis.
Abstract: The butanolic fraction (BT-II) derived from the aqueous crude extract was prepared from aerial parts of Baccharis trimera and assessed in anti-inflammatory, analgesia, and ulcerogenesis models. Intraperitoneal pretreatment with lyophilized BT-II, at doses ranging from 40 to 100 mg/kg, markedly inhibited carrageenan- and dextran-induced inflammation (70.4-90.8% and 25.7-71.3%, respectively) and weakly decreased C16-paf- and arachidonic acid-induced swelling (24.9-36.7% and 0-30.6%, respectively). No effect was observed, at the same doses, on zymosan-induced edema. The intraperitoneal examination indicates that the anti-phlogistic action of BT-II was not due to an irritating effect at the injection site. Besides, BT-II reduced abdominal constrictions in mice following injection of acetic acid: at 50 mg/kg, it gave 67.4% inhibition and, at 100 mg/kg, 95.1%. The ulcerogenic assay showed that the incidence of ulcers after BT-II i.p. treatment was 2/6 at 50 mg/kg and 6/6 at 100 mg/kg. Ulcerogenic indices were 1.3 +/- 0.5 and 2.7 +/- 0.8, respectively. These results indicate that B.trimera shows strong anti-inflammatory and analgesic properties which seem to be due, at least partly, to the inhibition of prostaglandin biosynthesis. The chromatographic separation of BT-II monitored by bio-assay (carrageenan-induced edema test in mice) was carried out. The active constituents were found to be mainly saponins in which echinocystic acid (or its enantiomer) is the major aglycone, and also rutin.
TL;DR: A role for BDNF in activity-dependent modifications of the adult cerebral cortex is supported and a clear-cut and specific upregulation of the BDNF mRNA expression was found at the level of the somatosensory cortex after the increased peripheral stimulation.
Abstract: Upregulation of brain-derived neurotrophic factor (BDNF) mRNA expression by neuronal activity has been reported in cultured hippocampal cells and in different in vivo excitotoxic paradigms. The aim of the present study was to determine whether sensory stimulation of the whisker-to-barrel pathway alters BDNF mRNA expression in the cortex and, if so, to evaluate the specificity of this effect. To this end, a set of mystacial whiskers was unilaterally stimulated by mechanical deflection, and the expression of BDNF mRNA was analyzed in the barrel cortex by in situ hybridization (ISH) using a 35S-labeled antisense BDNF riboprobe and emulsion autoradiography. A clear-cut and specific upregulation of the BDNF mRNA expression was found at the level of the somatosensory cortex after the increased peripheral stimulation. In the barrel cortex of control mice, BDNF mRNA was present in a few cells in layers II/III and VI, whereas it was almost undetectable in layer IV. After 6 hr of whisker stimulation, increased levels of BDNF mRNA were found in layers II to VI of the contralateral barrel cortex. In layer IV, BDNF upregulation was confined to the barrels corresponding to the stimulated follicles. ISH combined with immunocytochemistry against the three calcium-binding proteins parvalbumin, calretinin, and calbindin-D28K revealed that BDNF mRNA-expressing cells do not belong to the GABAergic cell population of the barrel cortex. The present results support a role for BDNF in activity-dependent modifications of the adult cerebral cortex.