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41.
Penicillium mycosis, or penicilliosis, is rare in animals. This report describes the clinical signs and pathological, immunohistochemical, and biomolecular findings in a case of avian penicilliosis in a Congo African grey parrot. On gross necropsy, pyogranulomatous changes were identified in the lung, liver, and kidney. Histopathology demonstrated periodic acid Schiff-(PAS) and Grocott-positive hyphae in these tissues. Immunohistochemistry confirmed the genus of the fungus and polymerase chain reaction (PCR) confirmed a high homology with Penicillium chrysogenum.  相似文献   
42.
Color is an important parameter involved in the definition of semolina and pasta quality. This character is mainly due to natural pigments (carotenoids) that are present at different levels in cereals and cereal products, due to botanical origin, growing conditions, distribution in the kernel, and technological processes. In food industries, color measurements are usually performed by means of automatic instruments that are rapid and safe, as alternatives to the chemical extraction methods. In this study, automatic measurements (CIE, color-space system L, a, b), water-saturated butanol (WSB), and HPLC determinations have been applied to evaluate the carotenoid content in whole meals and respective semolina samples produced from wheat cultivated in the years 2001 and 2002. In whole meals, total carotenoids, determined by HPLC, were about 3.0 microg/g (2001) and 3.5 microg/g (2002) calculated on dry weight (dw) and about 3.0 and 3.2 microg/g dw in corresponding semolina samples. The b values for the same period were 19.78 and 15.75, respectively, in raw materials and 20.03-21.67 in semolina. Results have confirmed lutein and beta-carotene as the main components mainly responsible for the yellow color in wheat grains. The ability of the index b to express natural dyeing was dependent on sample characteristics as demonstrated by the relationships found between this index and pigments, although the best correlation resulted between HPLC and WSB.  相似文献   
43.
Euplotin C is a sesquiterpene of marine origin endowed with significant anti-microbial and anti-tumor properties. Despite the promising functional profile, its progress as a novel drug candidate has failed so far, due to its scarce solubility and poor stability in aqueous media, such as biological fluids. Therefore, overcoming these limits is an intriguing challenge for the scientific community. In this work, we synthesized β-cyclodextrin-based nanosponges and investigated their use as colloidal carriers for stably complex euplotin C. Results obtained proved the ability of the carrier to include the natural compound, showing remarkable values of both loading efficiency and capacity. Moreover, it also allowed us to preserve the chemical structure of the loaded compound, which was recovered unaltered once extracted from the complex. Therefore, the use of β-cyclodextrin-based nanosponges represents a viable option to vehiculate euplotin C, thus opening up its possible use as pharmacologically active compound.  相似文献   
44.
The marine environment is a rich source of biologically active molecules for the treatment of human diseases, especially cancer. The adaptation to unique environmental conditions led marine organisms to evolve different pathways than their terrestrial counterparts, thus producing unique chemicals with a broad diversity and complexity. So far, more than 36,000 compounds have been isolated from marine micro- and macro-organisms including but not limited to fungi, bacteria, microalgae, macroalgae, sponges, corals, mollusks and tunicates, with hundreds of new marine natural products (MNPs) being discovered every year. Marine-based pharmaceuticals have started to impact modern pharmacology and different anti-cancer drugs derived from marine compounds have been approved for clinical use, such as: cytarabine, vidarabine, nelarabine (prodrug of ara-G), fludarabine phosphate (pro-drug of ara-A), trabectedin, eribulin mesylate, brentuximab vedotin, polatuzumab vedotin, enfortumab vedotin, belantamab mafodotin, plitidepsin, and lurbinectedin. This review focuses on the bioactive molecules derived from the marine environment with anticancer activity, discussing their families, origin, structural features and therapeutic use.  相似文献   
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Infrared spectra of material captured from comet 81P/Wild 2 by the Stardust spacecraft reveal indigenous aliphatic hydrocarbons similar to those in interplanetary dust particles thought to be derived from comets, but with longer chain lengths than those observed in the diffuse interstellar medium. Similarly, the Stardust samples contain abundant amorphous silicates in addition to crystalline silicates such as olivine and pyroxene. The presence of crystalline silicates in Wild 2 is consistent with mixing of solar system and interstellar matter. No hydrous silicates or carbonate minerals were detected, which suggests a lack of aqueous processing of Wild 2 dust.  相似文献   
47.
A wild strain of Agrobacterium rhizogenes was used to regenerate twelve in vitro plant lines from different hairy roots of H. perforatum (St. John's Wort). The production of the main bioactive constituents was observed even though their yields varied in the different plant lines. Two lines were selected for the hyperoside production (4.9-4.6 mg/gdw) while nine were characterized by significant yields of chlorogenic acid (ranged from 0.47 to 1.09 mg/gdw). Furthermore, one out of twelve lines showed a 10-fold higher hypericin content (0.25 mg/gdw) than that reported for the in vitro shoots in the literature. Morphological and phytochemical features were determined in order to select H. perforatum genotypes enriched in valuable bioactive compounds.  相似文献   
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Peritoneal lavage was performed on ponies to determine the effect on peritoneal surfaces. Lavage solution (20 L) was introduced into each pony's peritoneal cavity through catheters placed in the paralumbar fossa, and the solution was removed by drainage from the ventral portion of the abdomen. Six ponies each were lavaged with sterile saline (0.9% NaCl) solution, sterile saline solution containing 5 X 10(6) U of potassium penicillin and 3 g of neomycin or povidone-iodine diluted to 3% by volume with sterile saline solution, and 3 ponies were lavaged with povidone-iodine diluted to 10% with sterile saline solution. Peritoneal lavage catheters were inserted in 3 control ponies, but lavage fluids were not administered. Peritoneal fluid specimens were collected at 6, 24, 48, and 96 hours after lavage. Nucleated cell counts, RBC counts, total protein determinations, and cytologic analysis were performed. The ponies were euthanatized at 96 hours, and representative sections of the peritoneum were examined. Lavage with saline solution and saline solution with antibiotics induced a mild, transient inflammatory response in the peritoneal fluid, with minimal or no changes observed at necropsy. Solutions containing povidone-iodine induced chemical peritonitis, which was severe in ponies lavaged with 10% povidone-iodine solution. Peritoneal lavage with povidone-iodine solutions as dilute as 3% cannot be accomplished without causing inflammation of peritoneal surfaces.  相似文献   
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