Measurement of beta (t -> Wb)/beta(t -> Wq) at root s=1.96 TeV

We present the measurement of R = B(t -> Wb)/B(t -> Wq) in pp collisions at root s = 1.96 TeV, using 230 pb(-1) of data collected by the DO experiment at the Fermilab Tevatron Collider. We fit simultaneously R and the number (N-tt) of selected top quark pairs (tt), to the number of identified b-quark jets in events with one electron or one muon, three or more jets, and high transverse energy imbalance. To improve sensitivity, kinematical properties of events with no identified b-quark jets are included in the fit. We measure R = 1.03(-0.17)(0.19) (stat + syst), in good agreement with the standard model. We set lower limits of R > 0.61 and vertical bar V-tb vertical bar > 0.78 at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.

Search for Neutral Higgs Bosons at High tan beta in the b(h/H/A) -> b tau(+)tau(-) Channel

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

New phosphinate ligand synthesis and its effect on optical properties of the europium beta-diketonate complex

The synthesis and characterization of a new organic ligand monooctyldiphenylphosphinate (L) is described, as well as a new Eu(3+) diketonate complex [Eu(tta)(3)(L)(2)] (tta = thenoyltrifluoracetone). The ligand (L) was formed by substitution reaction (80% yield) and characterized by uni- and bidimensional (1)H, (13)C and (31)P NMR experiments, to confirm its molecular structure. The coordination of (L) to Eu(3+) in the complex [Eu(tta)(3)(L)(2)] was confirmed by FT-IR spectra. The emission spectra present the same profile when excited in Eu(3+) or in the ligands, suggesting an energy transfer from ligands to Eu(3+) ions. The emission spectra of the precursor [Eu(tta)(3)(H(2)O)(2)], and [Eu(tta)(3)(L(2))] present bands arising from f-f intra-configurational transitions. The only (5)D(0)-(7)F(0) transition shows the presence of at least one site without symmetry center. The FWHM of such transition is 7 cm(-1) and 57 cm(-1) for [Eu(tta)(3)(H(2)O)(2)] and [Eu(tta)(3)(L)(2)] complexes, respectively. This widening is provided by the presence of large groups around Eu(3+) ion. The calculated intensity parameters Omega(2) and Omega(4) show that the interaction features between center-ion and ligand are different; the small value of Omega(4) is related to long range effects of alkyl chain. The Langmuir isotherms of this ligand and complex have been investigated although their hydrolysis in water subphase does not allow stable monolayers. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Constituintes químicos isolados dos caules de Michelia champaca L. (Magnoliaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Concentração de progesterona e de estradiol 17-beta e características ultra-sonográficas da vesícula embrionária no início da gestação em éguas Puro Sangue Inglês

Associaram-se dosagens séricas de progesterona e estradiol 17-beta, realizadas durante os primeiros 36 dias de prenhez em 30 éguas PSI, com exames ultra-sonográficos, para verificar fenômenos que ocorrem com a vesícula embrionária. As éguas foram divididas em dois grupos de 15 animais, o primeiro constituído por éguas paridas e o segundo por éguas virgens ou vazias na estação anterior. Por meio da ultra-sonografia foram verificados fenômenos de mobilidade, fixação e orientação da vesícula embrionária. As concentrações séricas de progesterona e estradiol 17-B variaram (P<0,01) durante o período estudado porém não foi possível estabelecer uma correlação entre concentrações desses hormônios com desenvolvimento da vesícula embrionária. A concentração de estradiol 17-betacirculante foi maior (P<0,01) nas éguas paridas.

Atividade antimicrobiana in vitro da cefpiroma em comparação com outros beta-lactâmicos de amplo espectro contra 804 amostras clínicas de nove hospitais brasileiros

OBJETIVO: Avaliar a atividade in vitro da cefalosporina de quarta geração, cefpiroma em comparação com ceftazidima, ceftriaxona, cefotaxima e imipenem em um estudo multicêntrico envolvendo nove hospitais de seis cidades em quatro estados. MATERIAL E MÉTODOS: Foram estudadas 804 amostras clínicas isoladas em pacientes internados em unidades de terapia intensiva ou unidades de oncohematologia. As amostras foram coletadas no período de junho a novembro de 1995, isto é, antes da cefpiroma estar disponível comercialmente no Brasil, e testadas através do método de microdiluição em placas conforme descrito pelo National Committee for Clinical Laboratory Standards (NCCLS). Todas as amostras resistentes à cefpiroma foram retestadas utilizando-se o E-test. RESULTADOS: Contra as amostras de enterobactérias (n= 344), a cefpiroma apresentou atividade de 2 a 32 vezes superior àquela apresentada pelas cefalosporinas de terceira geração (CTGs) e semelhante àquela apresentada pelo imipenem. As porcentagens de enterobactérias sensíveis foram: 88% para a cefpiroma, 69% para as CTGs e 96% para o imipenem. O espectro de ação da cefpiroma foi maior ou igual ao do imipenem contra as espécies Citrobacter freundii, E. aerogenes, Morganella morganii e Serratia marcescens. Contra Acinetobacter sp. (n=77), a cefpiroma foi ligeiramente mais ativa que a ceftazidima, porém as porcentagens de resistência foram muito altas para esses compostos (84% e 88% respectivamente). As atividades da cefpiroma, ceftazidima e imipenem foram semelhantes contra Pseudomonas aeruginosa (n=128), com MIC50/porcentagem de sensibilidade de 8/59%, 8/62% e 4/62% respectivamente. Contra bactérias aeróbias gram-positivas, a cefpiroma foi de 4 a 16 vezes mais ativa que as CTGs. Contra S. epidermidis e outras espécies de estafilococos coagulase-negativos a cefpiroma foi ligeiramente superior ao imipenem, porém, contra as outras espécies de bactérias gram-positivas avaliadas, o imipenem apresentou atividade um pouco superior. CONCLUSÃO: Os resultados desse estudo sugerem que, no Brasil, a cefpiroma apresenta espectro de ação superior ao das CTGs contra bactérias gram-negativas (Enterobacteriaceae e não-fermentadares) e gram-positivas e semelhante ao do imipenem contra algumas espécies de enterobactérias e contra P. aeruginosa.

Chronotropic response of beta-adrenergic-, muscarinic-, and calcitonin gene-related peptide-receptor agonists in right atria from neonatal capsaicin-treated rats

We evaluated the potency of isoproterenol, carbachol, pilocarpine and calcitonin gene-related peptide (CGRP) in the rat right atria at 30, 60 and 90 days after neonatal capsaicin treatment. Neonatal rats were pretreated on the second day of life with capsaicin (50 mg/kg). The capsaicin pretreatment caused a five-fold rightward shift at the pEC(50) level on the concentration-response curves to isoproterenol in 30-day-old rats. Propranolol (10 mg/kg, given 15 min prior to capsaicin treatment) prevented this subsensitivity. No changes in the potency of isoproterenol were observed at 60 and 90 days after capsaicin pretreatment. The potency and maximal responses of CGRP in the right atria in 30-day-old rats were significantly higher than in 60- and 90-day-old rats; however, no differences were found between control and capsaicin groups. The potency and maximal responses to carbachol and pilocarpine were not changed in all groups. The neonatal capsaicin treatment reduced by about 74% the CGRP content in the heart in all groups. In summary, capsaicin treatment in newborn rats produces a desensitization of chronotropic response mediated by beta-adrenoceptors in isolated right atria from 30-day-old rats possibly due to a massive release of catecholamines. (C) 2002 Elsevier B.V. Ireland Ltd. All rights reserved.

Essential oil of the Pothomorphe peltata (L.) Miq.

The essential oils of leaves of the Pothomorphe peltata (L.) Miq., collected in vegetative and reproductive periods, showed yields of 0.10-0.20%. Analysis of the oil by GC/MS revealed that the predominant components were those of the sesquiterpene class. The major constituents were beta-caryophyllene (39.5-68.0%), germacrene D (6.2-13.3%), (E)-nerolidol (4.8-11.1%) and alpha-humulene (2.1-6.5%).

EFFECTS OF ENDOTOXIN, INTERLEUKIN-1-BETA AND PROSTAGLANDIN INJECTIONS ON FEVER RESPONSE IN BROILERS

1. The effect of endotoxin, interleukin-1 beta and prostaglandin on fever response was studied in 80 broilers (Hubbard strain). Endotoxin (E. coli, LPS) was injected iv (1.5 mu g/kg) and icv (1.5 mu g/bird); interleukin-1 (human recombinant IL-1 beta, 80 pg/bird) and prostaglandin E(2) (5 mu g/bird) were injected icv. Indomethacin (10 mg/kg, iv) pretreatment was also used before iv endotoxin injection. 2. The results showed that indomethacin was able to block the fever response induced by iv endotoxin injection, and IL-1 beta and PGE(2) were both effective in producing fever when injected icv. These data suggest a prostaglandin-mediated fever response by broilers, and also a strong evidence of the involvement of endogenous pyrogen (interleukin-1) in fever response in birds.

Cathodic stripping voltammetric determination of ceftazidime with reactive accumulation at a poly-L-lysine modified hanging mercury drop electrode

Ceftazidime is hydrolysed only slowly at pH 10 at room temperature. This is indicated by a small cathodic stripping voltammetric peak obtained at pH 10 at a hanging mercury drop electrode at about -0.6 V which corresponds to the reduction of the hydrolysis product. This peak is enhanced more than tenfold by the addition of poly-L-lysine (PLL) to the electrolyte solution. The optimum accumulation potential is between 0 and -0.1 V: the size of the peak decreases steadily, however, as the accumulation potential is moved to more negative potentials and is about one-sixth the size for accumulation at -0.4 V. Existing knowledge of the organic chemistry of cephalosporins indicates that the accumulation must involve an aminolysis reaction of the unprotonated PLL with the beta-lactam ring of the ceftazidime. The limit of detection (3 sigma) in standard solutions was calculated to be 1 x 10(-10) mol l(-1). The detection limit in buffer solution containing 1% of urine was calculated to be 5 x 10(-9) mol l(-1), i.e. 5 x 10(-6) mol l(-1) in the urine. (C) 1999 Elsevier B.V. B.V. AU rights reserved.

HYPERANDROGENISM DUE TO 3-BETA-HYDROXYSTEROID DEHYDROGENASE-DEFICIENCY WITH ACCESSORY ADRENOCORTICAL TISSUE - A HORMONAL AND METABOLIC EVALUATION

1. Adrenal ectopic tissue has been detected in the paragonadal region of normal women. In patients with congenital adrenal hyperplasia due to 21-hydroxylase (21-OH) deficiency, the manifestation of hyperplasia of paragonadal accessory adrenal tissue has been usually reported to occur in males. Probably, this is the first report of a female with 3beta-hydroxysteroid dehydrogenase (3beta-HSD) deficiency with ectopic adrenal tissue in ovaries. However, the occurrence of hyperplasia of adrenal rests among women with classical congenital adrenal hyperplasia may not be rare, especially among patients with a late diagnosis.2. We report a woman with 3beta-HSD deficiency whose definitive diagnosis was made late at 41 years of age immediately before surgery for the removal of a uterine myoma. During surgery, exploration of the abdominal cavity revealed the presence of bilateral accessory adrenal tissue in the ovaries and in the para-aortic region. The patient had extremely high levels of ACTH (137 pmol/l), DHEA (901.0 nmol/l), DHEA-S (55.9 mumol/l), androstenedione (70.2 nmol/l), testosterone (23.0 nmol/l) and 17alpha-hydroxypregnenolone (234.4 nmol/l) suggesting 3beta-HSD deficiency.3. In view of these elevated androgen levels, with an absolute predominance of DHEA and DHEA-S, we evaluated the effect of this hormonal profile on carbohydrate tolerance and insulin response to glucose ingestion.4. The patient presented normal glucose tolerance but her insulin response was lower than that of 14 normal women (area under the curve, 3beta-HSD = 17,680 vs 50,034 pmol/l for the control group over a period of 3 h after glucose ingestion).5. These results support recent data suggesting that patients with increased serum DHEA and DHEA-S levels do not present resistance to insulin.

Quantitative determination of maitenin and 22 beta-hydroxymaitenin in callus of Maytenus aquifolium (Celastraceae) by reverse phase high performance liquid chromatography

Explants of Maytenus aquifolium were induced to form callus and, subsequently, suspension cultures. The isolation of natural products from callus led to the identification of the cytotoxic triterpene quinonemethides, maitenin (1) and 22 beta-hydroxymaitenin (2), A rapid, sensitive and reliable reversed-phase high-performance liquid chromatography method was developed using a Cls column and isocratic elution for the determination of 1 and 2, the elaborated method gave well-resolved peaks for these compounds with good detection response and linearity in the range of 0.08-72.0 mu g. The quantification of 1 and 2 was performed by an external standard method. (C) 1998 John Wiley & Sons, Ltd.

Increased production of beta-1,3 glucanase and proteins in Bipolaris sorokiniana pathosystem treated using commercial xanthan gum

Barley plants (cultivars Embrapa 127, 128 and 129) treated with xanthan gum, and with different time intervals between the administration of the inducer and the pathogen, demonstrated induction of resistance against Bipolaris sorokiniana. Induction was shown to have local and systemic action. In order to prove the resistance effect, biochemical analyses were performed to quantify proteins and the enzymatic activity of beta-1,3 glucanase. Results demonstrated that barley plants treated with the inducer, showed an increase in the concentration of proteins, as well as in the activity of the enzyme beta-1,3 glucanase, when compared with the extract from healthy plants. In infected plants, protein concentrations decreased and enzymatic activity was lower than in healthy plants. Results suggest that barley plants treated with xanthan gum developed mechanisms responsible for induced resistance, which are still unknown. The most important macromolecule in the defense mechanism was demonstrated to be PR-protein, due to its accumulation and concentration of proteins. However, it may not be the only macromolecule responsible for the resistance effect. (C) 2004 Elsevier SAS. All rights reserved.

Disturbances in beta-cell function in impaired fasting glycemia

In a cross-sectional study, we assessed beta-cell function and insulin sensitivity index (ISI) with hyperglycemic clamps (10 mmol/l) in 24 subjects with impaired fasting glycemia (IFG, fasting plasma glucose [FPG] between 6.1 and 7.0 mmol/l), 15 type 2 diabetic subjects (FPG >7.0 mmol/l), and 280 subjects with normal fasting glycemia (NFG, FPG <6.1 mmol/l). First-phase insulin release (0-10 min) was lower in IFG (geometric mean 541 pmol/l (.) 10 min; 95% confidence interval [CI] 416-702 pmol/l (.) 10 min) and in type 2 diabetes (geometric mean 376 pmol/l (.) 10 min; 95% CI 247-572 pmol/l (.) 10 min) than NFG (geometric mean 814 pmol/l (.) 10 min; 95% CI 759-873 pmol/l (.) 10 min) (P < 0.001). Second-phase insulin secretion (140-180 min) was also lower in IFG (geometric mean 251 pmol/l; 95% CI 198-318 pmol/l; P = 0.026) and type 2 diabetes (geometric mean 157 pmol/l; 95% CI 105-235 pmol/l; P < 0.001) than NFG (geometric mean 295 pmol/l; 95% CI 276-315 pmol/l): IFG and type 2 diabetic subjects had a lower ISI (0.15 +/- 0.02 and 0.16 +/- 0.02 mumol/kg fat-free mass [FFM]/min/ pmol/l, respectively) than NFG (0.24 +/- 0.01 mumol/kg FFM/min/pmol/l, P < 0.05). We found a stepwise decline in first-phase (and second-phase) secretion in NFG subjects with progressive decline in oral glucose tolerance (P < 0.05). IFG subjects with impaired glucose tolerance (IGT) had lower first-phase secretion than NFG subjects with IGT (P < 0.02), with comparable second-phase secretion and ISI. NFG and IFG subjects with a diabetic glucose tolerance (2-h glucose >11.1 mmol/l) had a lower ISI than their respective IGT counterparts (P < 0.05). We conclude that the early stages of glucose intolerance are associated with disturbances in beta-cell function, while insulin resistance is seen more markedly in later stages.