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.

Opposite effects of bFGF and TGF-beta on collagen metabolism by human periodontal ligament fibroblasts

This study evaluated the effects of bFGF and TGF-beta, individually and combined, on cell proliferation and collagen metabolism. Primary human periodontal ligament cells were stimulated with two concentrations (I and 10 ng/ml) of each growth factor, both individually and combined. Proliferation was determined by a commercial biochemical assay. Real time RT-PCR determined gene expression of NMP-1 and -2, collagen types I and III, TIMP-1, -2 and -3. Autocrine effects on synthesis of bFGF and TGF-beta were evaluated by ELISA. Only TGF-beta, either isolated or associated with bFGF, significantly increased cell proliferation. TGF-beta had anabolic effects, increasing expression of type I and III collagen as well as of TIMPs, whereas bFGF had opposite effects. When bFGF and TGF-beta were associated, the anabolic effects prevailed. Synthesis of TGF-beta was induced only by the association of lower concentrations of the growth factors, whereas there was a dose-dependent production of bFGF. It is concluded that bFGF had a predominantly catabolic effect, and TGF-beta exerted an anabolic effect on hPDL cells. (c) 2007 Elsevier Ltd. All rights reserved.

REACTIONS OF MERCURIC ACETATE WITH PENTACARBONYLIRON IN ALCOHOLS - CRYSTAL AND MOLECULAR-STRUCTURES OF HG[FE(COOR)(CO)(4)](2) (R=CH3, C2H5)

Reactions of Hg(CH3COO)(2) with [Fe(CO)(5)] in MeOH and EtOH lead to the compounds Hg[Fe(COOR)(CO)(4)](2) (I for R = CH3 and II for R = C2H5). Crystals of I are triclinic, P (1) over bar, with a = 6.272(2), b = 6.441(3), c = 11.703(4) Angstrom, a = 92.94(3)degrees, beta = 103.77(3)degrees, gamma = 96.10(2)degrees, and Z = 1. Crystals of II are tetragonal, I4(1)/a, with a = 17.906(3) Angstrom, c = 12.756(2) Angstrom, and Z = 8. The geometry around Hg is linear for compound I and approximately linear for compound II. The Hg-Fe distances are 2.5716(8) and 2.575(4) Angstrom for compounds I and II, respectively. The geometry around the Fe in both compounds is approximately octahedral. The carboalkoxy group is cis to Hg in both compounds with Fe-C distances equal to 2.034(6) and 2.05(4) Angstrom for compounds I and II, respectively.

Crystal structure of bis(acetylacetonato)bis(quinoline)nickel(II), Ni(C5H14O2N)(2)(C9H7N)(2)

C28H28N2NiO4, triclinic, P (1) over bar (no. 2), a = 7.9202(6) angstrom, b = 8.0496(6) angstrom, c = 10.246(1) angstrom, alpha = 97.15(1)degrees, beta = 106.68(1)degrees, gamma = 94.686(9)degrees, V = 616.1 angstrom(3), Z = 1, R-gt(F) = 0.028, wR(ref)(F-2) = 0.078, T = 293 K.

Luminescence of Eu(III) beta-diketone complex supported on functionalized macroporous silica matrix

This work reports on the photoluminescent properties of the complex diequatris(thenoyltrifluoroacetonate) europium(III), which was adsorbed or supported on tubes of modified surface silica matrix. The luminescence data and the experimental intensity parameter results evidence the existence of high interactions between the complex [Eu(tta)(3)(H2O)(2)] and the modified surface matrix. The anchored complex on macroporous silica shows higher intensity parameter values suggesting that the Eu-0 bond becomes more covalent than the adsorbed one. Therefore, the hypersensitive character of the D-5(0) --> F-7(2) transition increases evidencing a high contribution of the dynamic coupling mechanism possibly due to highly polarizable chemical environments occupied by europium(III) ion. The lifetimes of the complex on silica matrices were measured. (C) 2001 Elsevier B.V. Ltd. All 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.

Structure of human uropepsin at 2.45 angstrom resolution

The molecular structure of human uropepsin, an aspartic proteinase from the urine produced in the form of pepsinogen A in the gastric mucosa, has been determined by molecular replacement using human pepsin as the search model. Crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 50.99, b = 75.56, c = 89.90 Angstrom. Crystallographic refinement led to an R factor of 0.161 at 2.45 Angstrom resolution. The positions of 2437 non-H protein atoms in 326 residues have been determined and the model contains 143 water molecules. The structure is bilobal, consisting of two predominantly beta -sheet lobes which, as observed in other aspartic proteinases, are related by a pseudo-twofold axis. A model of the uropepsin-pepstatin complex has been constructed based on the high-resolution crystal structure of pepsin complexed with pepstatin.

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.

Crystal structure of bis(benzyltriethylammonium) hexachlorotellurate(IV), [C7H7(C2H5)(3)N](2)(TeCI6)

C26H44Cl6N2Te, monoclinic, P12(1)/n1 (no. 14), a = 9.3981(5) Angstrom, b = 14.606(1) Angstrom, c = 12.4524(7) Angstrom, beta = 108.335(5)degrees, V = 1622.6 Angstrom(3), Z = 2, R-gt(F) = 0.024, wR(ref)(F-2) = 0.065, T = 293 K.

The effect of alpha-tocopherol on the oxidative cleavage of beta-carotene

Two cleavage pathways of beta-carotene have been proposed, one by central cleavage and the other by random (excentric) cleavage. The central cleavage pathway involves the metabolism of beta-carotene at the central double bond (15, 15') to produce retinal by beta-carotene 15, 15'-dioxygenase (E.C.888990988). The random cleavage of beta-carotene produces beta-apo-carotenoids, but the mechanism is not clear. To understand the various mechanisms of beta-carotene cleavage, beta-carotene was incubated with the intestinal postmitochondrial fractions of 10-week-old male rats for 1 h and cleavage products of beta-carotene were analyzed using reverse-phase, high-performance liquid chromatography (HPLC). We also studied the effects of alpha-tocopherol and NAD(+)/NADH on beta-carotene cleavage. In addition to beta-carotene, we used retinal and beta-apo-14'-carotenoic acid as substrates in these incubations. Beta-apo-14'-carotenoic acid is the two-carbon longer homologue of retinoic acid. In the presence of alpha-tocopherol, beta-carotene was converted exclusively to retinal, whereas in the absence of alpha-tocopherol, both retinal and beta-apo-carotenoids were formed. Retinoic acid was produced from both retinal and beta-apo-14'-carotenoic acid incubations only in the presence of NAD(+). Our data suggest that in the presence of an antioxidant such as alpha-tocopherol, beta-carotene is converted exclusively to retinal by central cleavage. In the absence of an antioxidant, beta-carotene is cleaved randomly by enzyme-related radicals to produce beta-apo-carotenoids, and these beta-apo-carotenoids can be oxidized further to retinoic acid via retinal. (C) 2000 Elsevier B.V.

Crystal structure of 1,1,3-trimethyl-2-(2-(2,2,6-trimethyl-cyclohexyl)ethyl) cyclohexane, C20H34

C20H34, monoclinic, P12(1)/n1 (no. 14), a = 10.647(l) angstrom, b = 6.6844(9) angstrom, c = 11.723(1) angstrom, beta = 99.75(1)degrees, V = 822.3 angstrom(3) Z = 2, R-gt(F) = 0.043, wR(ref)(F-2) = 0.110, T = 93 K.

Crystal structure of bis(acetylacetonato)-bis(3-methylpyridine)-nickel(II) dihydrate, Ni(C6H7N)(2)(C5H7O2)(2)center dot 2H(2)O

C22H32N2NiO6, triclinic, P (1) over bar (no. 2), a = 8.335(1) angstrom, b = 9.314(1) angstrom, c = 17.045(2) angstrom, alpha = 88.45(1)degrees, beta = 82.12(1)degrees, gamma = 70.296(9)degrees, V = 1233.7 angstrom(3), Z = 2, R-gt(F) = 0.050, wR(ref)(F-2) = 0.177, T = 293 K.