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61.
New Drug‐Structure‐Directing Agent Concept: Inherent Pharmacological Activity Combined with Templating Solid and Hollow‐Shell Mesostructured Silica Nanoparticles 下载免费PDF全文
Victoria Morales María Gutiérrez‐Salmerón Moisés Balabasquer Josefa Ortiz‐Bustos Ana Chocarro‐Calvo Custodia García‐Jiménez Rafael A. García‐Muñoz 《Advanced functional materials》2016,26(40):7291-7303
One of the major challenges in medicine is the delivery and control of drug release over time. Current approaches take advantage of mesostructured silica nanoparticles (MSNs) as carriers but suffer several problems including complex synthesis that requires sequential steps for (1) removal of surfactants and (2) functionalization of MSNs to allow upload of the drugs. Here, a novel solution is presented to these restrictions: the design of drug‐structure‐directing agents (DSDAs) with dual inherent pharmacological activity and ability to direct the formation of solid and hollow‐shell MSNs. Pharmacologically active DSDAs obtained by amidation of drugs with fatty acids are allowed to form micelles, around which the inorganic species self‐assembled to form MSNs. Since the DSDAs direct the formation of MSNs, the steps to remove surfactants, functionalization, and drug upload are not required. The MSNs thus prepared provide sustained release of the drug over more than six months, as well as rapid cellular internalization by both physiological and tumoral human colon cells without affecting cell viability. Moreover, the gradual intracellular release of both, the active drug and lipid moiety with potential nutraceutical properties is proved. MSN particles designed with this approach are promising vehicles for controlled and sustained intra‐or extracellular drug‐delivery. 相似文献
62.
A Otero M C García M L García B Moreno 《International journal of food microbiology》1988,6(2):107-114
Staphylococcus aureus strains FRI 137 (enterotoxin C1 producer) and FRI 361 and L 2 (enterotoxin C2 producers) were grown alone and in the presence of a mixed commercial starter culture (Streptococcus lactis, Streptococcus cremoris and Streptococcus lactis subsp. diacetylactis). Lactic acid bacteria had a slight inhibitory effect on S. aureus population and only during the late stages of growth. In contrast, enterotoxin synthesis was strongly inhibited, inhibition at 18 h being 89% (FRI 137), 80% (FRI 361) and 69% (L 2). Enterotoxin C1 was produced and accumulated during all phases of growth in pure and mixed culture, but associative growth resulted in reduction of enterotoxin C2 after 24-36 h. In mixed culture, high producers of thermonuclease (FRI 137 and L 2) showed an early decrease in enzyme activity followed by an increase, but it never reached levels attained in pure culture. Thermonuclease was detected whenever enterotoxin was detected, but production curves did not parallel each other. 相似文献
63.
A Navarro Izquierdo C San Roman Terán JM Pereda García 《Canadian Metallurgical Quarterly》1976,141(1):33-37
This study reports the results of analysis concerning some chemical characteristics of 63 samples of tomato juice and paste. Copper was determined by atomic absorption spectrometry and its average content was 32 ppm. This is not a critical value for human health and results below the upper limit provided by law of several european and not european countries. 相似文献
64.
In recent years application of computer techniques to various problems in biology has increased. In the field of anesthesia, where rapid changes appearing in a short time must be followed, the conventional, mannual methods are not applicable. So we have developed on-line computer analytical methods of cardiovascular function. Hybrid systems are the preferred methods in many biological problems, either because of efficiency and lower cost, or because of real time, on-line, closed-loop capabilities for direct use during experiments. As a computer output we used a graphic display computer and cathod ray tube devices. We applied these systems to analize and calculate cardiac work with other circulatory parameters. We got a ventricular function curve in visible form on CRT within 30 seconds after introducing the signals of left ventricular work and ventricular end-diastolic pressure into the analog computer. It was also useful to calculate vascular input impedence and myocardial maximal velocity of shortening. Finally causes of input errors in these analytical methods were discussed. 相似文献
65.
JL López Sendón J Carrillo Kabana J Silvestre García J Calderón Montero 《Canadian Metallurgical Quarterly》1976,29(3):251-257
By reviewing the syndromic manifestation, transsexualism in characterized as a psychiatric entity, apart from homossexualism and transvestism. The two main feasible etiologic causes of transsexualism are discussed: the psychoanalytical hypothesis based upon psycossexual regression with imprinting of maternal figure and the neuroendocrine model which assumes alterations of the gender role identity centers in the hypothalamus. On the grounds of the latter explanation and after the scheme that seems to occure in the Morris syndrome whose cells (XY) do not respond to the masculinizing effect of plasma testosterone, it is proposed that transsexuals should possess detectable or cryptic sex-chromosome mosaicism affecting hypothalamic centers of gender role identity which do not respond to the androgenic secretion produced by primitive gonad. This possibliity explains the excessive prevalence of the syndrome among men, its typical features in the male as well as its sporadic occurrence. Cytogenetic investigation reveals that the frequency (32%) of sex-chromosome mosaicism among 25 transsexuals and 40 normal control people, both groups presenting the proportion of the mosaicism practically null. The karyotypic criterion as a valuable aid in the syndrome diagnosis is considered. 相似文献
66.
67.
The intramuscular fat content, its fatty acid composition and that from the triglyceride fraction, were determined in several muscles from the right sides of four Duroc Jersey and four Hampshire castrated male pigs slaughtered at 100 kg liveweight. The Hampshires had heavier muscles than the Duroc Jersey pigs, but did not show significant differences in the percentages of intramuscular fat. The concentrations of linoleic acid were, in general, higher in the Hampshire than in the Duroc Jersey pigs and in many muscles the differences were highly significant (p < 0·05) The concentrations of linoleic acid (18:2) in the triglyceride fraction did not differ among muscles within breeds but were higher in Hampshire than in Duroc Jersey pigs. 相似文献
68.
The partitioning of total dissectible body fat and the amounts of intramuscular fat in Psoas major, Semitendinosus and Biceps brachii muscles were determined in two groups of A. Angus and AA × Nelore steers with similar averages of total dissectible fat (27·7 kg). In addition, the fatty acid composition of total fat and the triglyceride fraction from dissectible and intramuscular fats were determined.
The AA × Nelore steers have higher levels of subcutaneous fat and lower levels of intermuscular fat than the A. Angus but contain lower levels of intramuscular fat in the three muscles. The allometric regressions varied according to the muscle and breed type. The fatty acid composition of subcutaneous and kidney fats were similar but differences in the percentages of 14:0, 18:0, 18:2 and 20:4 fatty acids in intramuscular fats between the two genetic groups were detected. 相似文献
69.
María José García José Luis Aleixandre Inmaculada Álvarez Victoria Lizama 《European Food Research and Technology》2009,229(1):133-139
Fining agents can also have an effect on the flavor components of the must, and other compounds which are important for the
sensory characteristics and in the case of sparkling wine, the foam quality. The influence of fining agents and tirage solution,
on volatile compounds, and foam characteristics of sparkling wines made from grapes of the Bobal variety was studied. The
data obtained show how the fining agent affects the foam properties and the final volatile composition of sparkling wines.
In this study, it was bentonite with gelatine that produced amounts of acetates and esters. The use of Colle 2P in the tirage
solution means that more aromatic sparkling wines with better foam characteristics can be obtained. 相似文献
70.
Preference ranking tests for juiciness and overall liking of dry cured loins from Iberian pigs with different genetic backgrounds (pure Iberian or crossbred Iberian×Duroc pigs), reared under different productive systems (outdoors on acorns and grass or indoors with mixed diets) and with different intramuscular fat (IMF) content, were conducted. IMF showed a positive influence on preference for juiciness and liking in subjects over 25 years of age, while younger consumers showed a similar trend for juiciness but not for preference. Loins from pure Iberian pigs showed significantly better ranking for juiciness and overall liking than those from crossbred pigs, even when the IMF content was similar. Dry cured loins from pigs reared outdoors and fed on acorns and pasture were ranked significantly better than those from animals fed indoors on concentrates, even though the mixed diets used were enriched in monounsaturated fatty acids and vitamin E in order to obtain meat with similar features to that of pigs reared outdoors, and despite very similar IMF contents. In conclusion, dry cured loins with high IMF content, from pure Iberian pigs and reared outdoors on acorns and grass attain the highest consumer preference. 相似文献