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11.
Casearia species are found in the America, Africa, Asia, and Australia and present pharmacological activities, besides their traditional uses. Here, we reviewed the chemical composition, content, pharmacological activities, and toxicity of the essential oils (EOs) from Casearia species. The EO physical parameters and leaf botanical characteristics were also described. The bioactivities of the EOs from the leaves and their components include cytotoxicity, anti-inflammatory, antiulcer, antimicrobial, antidiabetic, antioxidant, antifungal, and antiviral activities. The main components associated with these activities are the α-zingiberene, (E)-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, α-humulene, β-acoradiene, and δ-cadinene. Data on the toxicity of these EOs are scarce in the literature. Casearia sylvestris Sw. is the most studied species, presenting more significant pharmacological potential. The chemical variability of EOs components was also investigated for this species. Caseria EOs have relevant pharmacological potential and must be further investigated and exploited.  相似文献   
12.
Conclusiones Se efectúa el estudio de 5 observaciones del llamado Micetoma maduromicósico de pulmón en sus aspectos, histopatológico, micológico y clínico.Todas ellas pertenecen a mujeres y configuraron el cuadro de cavidad bronquial empastada, anotando el predominio de su localización en el lóbulo superior izquierdo.Se señala la uniformidad de los caracteres morfológicos que presenta la masa miceliana llamada grano en todos los casos estudiados, en los cuales no fué posible individualizar la existencia de órganos de fructificación que permitiéran una clasificación, cuando más no fuera, genérica del hongo observado.Se critica la aplicación del término Micetoma para éstos casos con igual criterio que el clásico, que supone una enfermedad micótica primitiva, razón por la cual se prefiere hablar de cavidad con contenido micótico o maduromicótico.En el único caso que se logró cultivar al hongo parásito, el estudio micológico del mismo permitió aislar una especie del GéneroAspergillua con caracteres morfológicos sumamente atípicos.
Summary The author presents the study of five observations of the so-called Maduromycosis-mycetoma of the lungs in their clinical, histopathologic and mycologic aspects.The pathologic features in all these cases have been found in bronchial cavities of women, situated in the upper lobe of the lung. A compact mycelial mass, the grain, filled up these cavities.In one of the five cases a fungus was cultivated which was classified as belonging to the GenusAspergillus Michelii, with abnormal and atypical features.Short criticism is presented about the concept Maduromycosis mycetoma of the lung, applied by authors designating this process.
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13.
Rapeseed (Brassica napus) is a crop relatively tolerant to salt and sodium. Our objective was to study the interactions between Na, K and Ca and their relationship with its yield under the isolated effects of soil salinity or sodicity.Two experiments were carried out using pots filled with the Ah horizon of a Typic Natraquoll. There were three salinity levels (2.3 dS m-1; 6.0 dS m-1 and 10.0 dS m-1) and three sodicity levels, expressed as sodium adsorption ratios (SAR: 12; 27 and 44). The soil was kept near field capacity.As soil salinity increased, the K/Na and Ca/Na ratios in the tissues decreased markedly but yields and aerial biomass production were not affected. As soil SAR value increased, the K/Na and Ca/Na ratios in plants and K-Na and Ca-Na selectivities decreased. Plants could not maintain their Ca concentration in soil with a high SAR. The grain yield and biomass production diminished significantly in the highest SAR treatment. Our results are consistent with those showing detrimental osmotic effects of salts in Brassica napus. Conversely, under sodicity, the K/Na and Ca/Na ratios in plant tissues decreased considerably, in accordance with grain and biomass production. These results show that the effects of sodicity are different from those of salinity.  相似文献   
14.
The combining site of the Bauhinia purpurea alba lectin was studied by quantitative precipitin and precipitin inhibition assays. Of 45 blood group substances, glycoproteins, and polysaccharides tested, 35 precipitated over 75% of the lectin. Precursor blood group substances with I activity (Cyst OG 10% from 20% and Cyst OG 20% from 10%), desialized fetuin, and desialized ovine salivary glycoprotein, in which more than 75% of the carbohydrate side chains have dGalN Ac linked through α1 → to the OH group of Ser or Thr of a protein core, completely precipitated the lectin. The poorly reactive blood group substances after mild acid hydrolysis or Smith degradation, as well as sialic acid-containing glycoproteins after removal of sialic acid, had substantially increased activity so that more than 80% of the lectin was precipitated. Precipitability with various blood group substances and glycoproteins is ascribable to the terminal nonreducing dGalNAc, dGalβ1 → 3dGalNAc, dGalβ1 → 3 or 4dGlcNAc, and dGalβ1 → 3 or 4dGlcNAcβ1 → 3dGal determinants on the carbohydrate moiety. Of the monosaccharides tested for inhibition of precipitation, dGalNAc and its p-nitrophenyl and methyl α-glycosides were best. These compounds were four to five times better than the corresponding dGal compounds but methyl βDGalNAcp was only about 40% more active than methyl βdGalp. The α-anomers of p-nitrophenyl DGalNAcp and dGalp, were twice as active as the corresponding β-anomers. Methyl αDGalNAcp was four times as active as the β-anomer but the inhibitory power of the methyl α- and β-anomers of dGal were about equal. Among the oligosaccharides tested, dGalβ1 → 3dGalNAc and its tosyl derivatives were most active, the tosyl glycosides being about twice as active as dGalβ1 → 3dGalNAc, which was somewhat more active than dGalNAcα1 → 6dGal and dGalNAc, and 2.5 and 5 times as active as dGalNAcα1 → 3dGalβ1 → 3dGlcNAc and dGalNAcαl → 3dGa1, respectively (blood group A specific). These findings suggest that a subterminal dGalNAc β-linked and substituted on carbon 3 plays an important role in binding. Consistent with this inference are the findings that dGalβ1 → 3dGlcNAc and dGalβ1 → 6dGal were poorer inhibitors although dGalβ1 → 3dGlcNAc was two to three times as active as glycosides of dGal. Oligosaccharides with terminal nonreducing dGal and subterminal α-linked dGal were as active or less active than dGal. dGalβ1 → 3dGlcNAcβ1 → 3dGalβ1 → 4dGlc (lacto-N-tetraose) and dGalβ1 → 3dGlcNAcβ1 → 3dGal-β1-O-(CH2)8COOCH3 were equally active and 1.5 times as potent as dGalβ1 → 3dGlcNAc whereas dGalβ1 → 3dGlcNAcβ1 → 6dGal was only 40% as potent as dGalβ1 → 3dGlcNAc suggesting that a third sugar may be part of the determinant. Substitution of dGalβ1 → 3dGlcNAcβ1 → 3dGalβ1 → 4dGlc on the subterminal dGlcNAc by lFucα1 → 4 in lacto-N-fucopentaose II reduced activity fourfold; if the nonreducing dGal is substituted by lFucα1 → 3 as in lacto-N-fucopentaose I its activity is almost completely abolished. This suggests that a terminal nonreducing dGal as well as subterminal dGlcNAc are contributing to binding. The β → 3 linkage of the terminal dGal to the subterminal amino sugar is significant since dGalβ1 → 4dGlcNAc is a poorer inhibitor. Although the available data suggest that the combining site of the lectin Bauhinia purpurea alba may be most complementary to the structure dGalβ1 → 3dGalNAcβ1 → 3dGal, several other possibilities remain to be tested when suitable oligosaccharides become available.  相似文献   
15.
Six newborns with obstructive right heart lesions were examined neurologically and electroencephalographically during treatment with prostaglandin (PG) E1 or E2 given to maintain patency of the ductus arteriosus and to increase pulmonary blood flow. PG was administered intravenously or intraarterially in the aortic isthmus proximal to the ductus arteriosus. Besides a rise in arterial oxygen saturation, all patients had some sign of central nervous system involvement. The electroencephalogram showed minor changes suggestive of sedation. In addition, three patients in whom PG given intravenously presented various combinations of neurological abnormalities (“myoclonic jerks”, apnoeic spells, hiccup) of subcortical origin. Side-effects subsided after stopping the treatment anf posed no problem in the management of the patients. These findings confirm the usefulness and safety of the PG therapy and indicate that the intraaortic route of administration is preferable.  相似文献   
16.
Carbohydrate structures in the interior of a blood group A active substance (MSS) were exposed by one and by two Smith degradations. Reactivities of the original glycoprotein and its Smith degraded products with 13 different lectins and with anti-I Ma were studied by quantitative precipitin assay. MSS and its first Smith degraded product completely precipitated Ricinus communis hemagglutinin with five times less of the first Smith degraded glycoprotein being required for 50% precipitation. The second Smith degraded material precipitated only 90% of the lectin. MSS did not precipitate peanut lectin, whereas its first and second Smith degraded products completely precipitated the lectin. The first Smith degraded glycoprotein also reacted well with Wistaria floribunda, Maclura pomifera, Bauhinia purpurea alba, and Geodia lectins indicating that its carbohydrate moiety could contain dGalNAc, dGalβ1 → 3dGalNAc, dGalβ1 → 4dGlcNAc, dGalβ1 → 3dGlcNAcβ1 → 3dGal and/or dGalβ1 → 4dGlcNAcβ1 → 6dGal and/or dGalβ1 → 4dGlcNAcβ1 → 6dGalNAc determinants at nonreducing ends. The second Smith degraded material precipitated well with Ricinus communis hemagglutinin, Arachis hypogaea, Geodia cydonium, Maclura pomifera, and Helix pomatia lectins showing that dGalNAc, dGalβ1 → 3dGalNAc, dGalβ1 → 4dGlcNAc residues at terminal nonreducing ends could be involved. Monoclonal anti-I Ma (group 1) serum reacted strongly with the first Smith degraded product indicating large numbers of anti-I Ma determinants, dGalβ1 → 4dGlcNAcβ1 → d 6dGal and/or dGalβ1 → 4dGlcNAcβ1 → 6dGalNAc at nonreducing ends. The comparable activities of the native and Smith degraded products with wheat germ lectin indicate capacity to react with DGlcNAc residues at nonreducing ends and/or at positions in the interior of the chain. The totality of lectin reactivities indicates heterogeneity of the carbohydrate side chains. Oligosaccharides with 3H at their reducing ends released from the protein core of the first and second Smith degraded products were obtained by treatment with 0.05 m NaOH and 1 M NaB3H4 at 50 °C for 16 h (Carlson degradation). The liberated reduced oligosaccharides were fractionated by dialysis, followed by retardion, Bio-Gel P-2, P-4, and P-6 columns. They were further purified on charcoal-celite columns, and by preparative paper chromatography and high-pressure liquid chromatography. Their distribution by size was estimated by the yields on dialysis, Bio-Gel P-2, and Bio-Gel P-6 chromatography, and from the radioactivity of the reduced sugars. Of the oligosaccharide fractions from the first Smith degraded product, about 77% of the carbohydrate side chain residues contained from 1 to 6 sugars, 13% from 7 to perhaps 12 sugars, and 10% was nondialyzable (polysaccharides and glycopeptide fragments). Of the second Smith degraded product, approximately 82% of carbohydrate residues had from 1 to 6 sugars, 14% from 7 to perhaps 20 sugars and 4% was nondialyzable. The biological activity profile of the two Smith degraded products together with the size distributions of the oligosaccharides indicated that their carbohydrate side chains, comprised a heterogeneous population ranging in size from 1 to about 12 sugars. When most of these chains that are shorter than hexasaccharides are fully characterized it may be possible to reconstruct the overall structure of the carbohydrate moiety of the blood group substances and account for their biological activities.  相似文献   
17.
Quinolinic acid, an endogenous excitotoxin, and kynurenic acid, an antagonist of excitatory amino acid receptors, are believed to be synthesized from tryptophan after the opening of the indole ring. They were measured in the rat brain and other organs using gas chromatography-mass spectrometry or HPLC. The enzyme indoleamine 2,3-dioxygenase, capable of cleaving the indole ring of tryptophan, was induced by administering bacterial endotoxins to rats, which significantly increased the brain content of both quinolinic and kynurenic acids. Nicotinylalanine, an analogue of kynurenine, inhibited this endotoxin-induced accumulation of quinolinic acid while potentiating the accumulation of kynurenic acid. The possibility of significantly increasing brain concentrations of kynurenic acid without a concomitant increase in quinolinic acid may provide a useful approach for studying the role of these electrophysiologically active tryptophan metabolites in brain function and preventing the possible toxic actions of abnormal synthesis of quinolinic acid.  相似文献   
18.
Lowering the pH of the incubation medium to pH 5.4 leads to grana formation morphologically similar to that induced by metal cations. The same phenomenon is observed in EDTA-washed chloroplasts, indicating that it is not due in part to electrostatic ‘masking’ by residual cations associated with the membranes. Digitonin fractionation studies have indicated that the distribution of the major chlorophyll-protein complexes between granal and stromal membrane regions is similar at pH 5.4 in the absence of Mg2+, and at pH 7.4 in the presence of Mg2+. Chlorophyll fluorescence induction studies have indicated that the primary photochemistry of Photosystem II (PS II) is stimulated by lowering the pH to 5.4, just as it is upon metal cation addition at higher pH values. The failure to observe such an increase at pH 5.4 by measuring electron transport to ferricyanide is attributed to a combination of an inhibition by this pH of electron transport at a site after Q reduction and an increase in the number of PS II centres detached from the plastoquinone pool. We conclude that the stacked configuration of chloroplast membranes leads to increased PS II primary photochemistry, which is most simply explained in terms of a redistribution of excitation energy towards PS II.  相似文献   
19.
The prostaglandin synthesis inhibitors, indomethacin and eicosa-5,8,11, 14-tetraynoic acid (ETA), have been tested on the isolated lamb ductus arteriosus at low and high PO2 levels. Both compounds produced a gradual contraction of the hypoxic vessel, and at equal doses the effect of indomethacin was stronger. The maximal tension output of the hypoxic tissue under indomethacin was equal to that of the oxygen-contracted control. ETA- and indomethacin-treated preparations contracted further upon transfer from a low to a high oxygen environment, and the response under indomethacin exceeded significantly control values. Control preparations were relaxed markedly by PGE2 in low oxygen but showed little or no response in high oxygen. In contrast, preparations pretreated with the inhibitors retained their sensitivity to PGE2 during exposure to high oxygen. The data are consistent with the idea that E-type prostaglandins play a role in the regulation of the intrinsic tone of the ductus arteriosus during foetal life. It is also suggested that the sensitivity of ductal muscle to E-type prostaglandins is controlled by the rate of endogenous prostaglandin formation.  相似文献   
20.
BackgroundWe compared protection of mycophenolate mofetil (MMF) and azathioprine (AZA) against acute cellular rejection (ACR) and chronic allograft nephropathy (CAN) in kidney transplant recipients on steroid-free, low-dose cyclosporine (CsA) microemulsion maintenance immunosuppression.Methods and findingsATHENA, a pragmatic, prospective, multicenter trial conducted by 6 Italian transplant centers, compared the outcomes of 233 consenting recipients of a first deceased donor kidney transplant induced with low-dose thymoglobulin and basiliximab and randomized to MMF (750 mg twice/day, n = 119) or AZA (75 to 125 mg/day, n = 114) added-on maintenance low-dose CsA microemulsion and 1-week steroid. In patients without acute clinical or subclinical rejections, CsA dose was progressively halved. Primary endpoint was biopsy-proven CAN. Analysis was by intention to treat.Participants were included between June 2007 and July 2012 and followed up to August 2016. Between-group donor and recipient characteristics, donor/recipient mismatches, and follow-up CsA blood levels were similar. During a median (interquartile range (IQR)) follow-up of 47.7 (44.2 to 48.9) months, 29 of 87 biopsied patients on MMF (33.3%) versus 31 of 88 on AZA (35.2%) developed CAN (hazard ratio (HR) [95% confidence interval (CI)]: 1.147 (0.691 to 1.904, p = 0.595). Twenty and 21 patients on MMF versus 34 and 14 on AZA had clinical [HR (95% CI): 0.58 (0.34 to 1.02); p = 0.057) or biopsy-proven subclinical [HR (95% CI): 1.49 (0.76 to 2.92); p = 0.249] ACR, respectively. Combined events [HR (95% CI): 0.85 (0.56 to 1.29); p = 0.438], patient and graft survival, delayed graft function (DGF), 3-year glomerular filtration rate (GFR) [53.8 (40.6;65.7) versus 49.8 (36.8;62.5) mL/min/1.73 m2, p = 0.50], and adverse events (AEs) were not significantly different between groups.Chronicity scores other than CAN predict long-term graft outcome. Study limitations include small sample size and unblinded design.ConclusionsIn this study, we found that in deceased donor kidney transplant recipients on low-dose CsA and no steroids, MMF had no significant benefits over AZA. This finding suggests that AZA, due to its lower costs, could safely replace MMF in combination with minimized immunosuppression.Trial registrationClinicalTrials.gov NCT00494741; EUDRACT 2006-005604-14.

Piero Ruggenenti and co-workers study maintenance immunosuppression in deceased-donor kidney transplantation.  相似文献   
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