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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 presence of acyl-CoA synthetase (EC 6.2.1.3) in peroxisomes and the subcellular distribution of beta-oxidation enzymes in human liver were investigated by using a single-step fractionation method of whole liver homogenates in metrizamide continuous density gradients and a novel procedure of computer analysis of results. Peroxisomes were found to contain 16% of the liver palmitoyl-CoA synthetase activity, and 21% and 60% of the enzyme activity was localized in mitochondria and microsomal fractions respectively. Fatty acyl-CoA oxidase was localized exclusively in peroxisomes, confirming previous results. Human liver peroxisomes were found to contribute 13%, 17% and 11% of the liver activities of crotonase, beta-hydroxyacyl-CoA dehydrogenase and thiolase respectively. The absolute activities found in peroxisomes for the enzymes investigated suggest that in human liver fatty acyl-CoA oxidase is the rate-limiting enzyme of the peroxisomal beta-oxidation pathway, when palmitic acid is the substrate.  相似文献   
15.
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   
16.
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   
17.
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   
18.
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   
19.
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   
20.
Two in vivo assay procedures were used to study the inhibitory activity of cholesterol carried in three intestinal lymph and three serum lipoprotein fractions on the rate of cholesterol synthesis in the liver. In the first preparation, different lipoproteins were injected intravenously as a bolus into rats at the mid-light phase of the diurnal light cycle, following which they were killed 12 hours later in the mid-dark phase of the cycle. Using this assay, three intestinal lymph lipoprotein fractions of varying Sf values all produced a similar degree of inhibition which averaged approximately 11%/mg of cholesterol injected. The serum lipoprotein fractions caused only about one-third this amount of inhibition. Detailed analysis of events occurring within the liver during this 12-hour assay period revealed that there were marked differences in the rate of net cholesterol uptake into the liver and in the rate of new removal of cholesterol esters from the liver following injection of each of these different lipoprotein fractions. The amount of inhibition of sterol synthesis produced by any fraction was proportional to the product of the incremental increase in hepatic cholesterol ester content and the time over which this increase in esters occurred. In the second type of assay where the lipoprotein fractions were administered to the animals as a continuous intravenous infusion over 24 hours the largest increase in hepatic cholesterol ester content and the greatest inhibition of cholesterol synthesis was found with intestinal lipoproteins having Sf values larger than 8000. Intestinal lipoprotein fractions with lower Sf values and all serum lipoprotein fractions were significantly less effective in bringing about an increase in hepatic cholesterol ester content and in producing inhibition of cholesterol synthesis by the liver. These studies emphasize the primary role of cholesterol carried in lipoproteins of intestinal origin in regulating hepatic sterol synthesis. The inhibitory activity of these fractions appears to correlate with the ability of these lipoproteins to bring about a maximal increase in hepatic cholesterol ester content which, in turn, appears to relate to the capacity of these fractions to transfer cholesterol rapidly into the hepatocyte while, at the same time, slowing the rate of cholesterol mobilization from the liver.  相似文献   
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