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1.
Jorge Lobo’s disease (JLD) is a chronic infection that affects the skin and subcutaneous tissues. Its etiologic agent is the fungus Lacazia loboi. Lesions are classified as localized, multifocal, or disseminated, depending on their location. Early diagnosis and the surgical removal of lesions are the best therapeutic options currently available for JLD. The few studies that evaluate the immunological response of JLD patients show a predominance of Th2 response, as well as a high frequency of TGF-β and IL-10 positive cells in the lesions; however, the overall immunological status of the lesions in terms of their T cell phenotype has yet to be determined. Therefore, the objective of this study was to evaluate the pattern of Th1, Th2, Th17 and regulatory T cell (Treg) markers mRNA in JLD patients by means of real-time PCR. Biopsies of JLD lesions (N = 102) were classified according to their clinical and histopathological features and then analyzed using real-time PCR in order to determine the expression levels of TGF-β1, FoxP3, CTLA4, IKZF2, IL-10, T-bet, IFN-γ, GATA3, IL-4, IL-5, IL-13, IL-33, RORC, IL-17A, IL-17F, and IL-22 and to compare these levels to those of healthy control skin (N = 12). The results showed an increased expression of FoxP3, CTLA4, TGF-β1, IL-10, T-bet, IL-17F, and IL-17A in lesions, while GATA3 and IL-4 levels were found to be lower in diseased skin than in the control group. When the clinical forms were compared, TGF-β1 was found to be highly expressed in patients with a single localized lesion while IL-5 and IL-17A levels were higher in patients with multiple/disseminated lesions. These results demonstrate the occurrence of mixed T helper responses and suggest the dominance of regulatory T cell activity, which could inhibit Th-dependent protective responses to intracellular fungi such as L. loboi. Therefore, Tregs may play a key role in JLD pathogenesis.  相似文献   
2.
Summary C. sitophila strain TFB-27441 showed 2–3 times higher lignolytic activity thanPhanerochaete chrysosporium (BKM-F-1767 strain). Lignin had a marked effect on the ligninase activity indicating that some induction or activation mechanism is involved in lignin degradation byC. sitophila.  相似文献   
3.
The mechanism of extraction of rat cytochrome b(5) from water into a sodium dioctylsulfosuccinate (AOT) micellar organic phase was studied using protein engineering of surface charged residues. The extraction behavior of native cytochrome b(5) and modified proteins with substitutions of the type glutamic acid --> lysine at positions 44 (E44K), 56 (E56K), and 92 (E92K), was studied as a function of pH. The results indicate that an important mechanism of extraction is an electrostatic interaction of this protein with the negatively charged surfactant. We demonstrate that it is possible to improve extraction by engineering the protein surface charge, increasing the driving force responsible for the protein transfer to the micellar phase. (c) 1994 John Wiley & Sons, Inc.  相似文献   
4.
Gyrodactylus gemini n. sp. (Monogenea, Gyrodactylidae) is described from the surface of the body and fins of the fish Semaprochilodus taeniurus (Steindachner) imported into Britain from the Venezuelan Amazon. The new species differs from other species of the genus, including those described from South and Central America, by having: (i) stout hamuli with straight shafts and diverging roots; (ii) marginal hooks with the sickle length larger than the width; (iii) a dorsal bar without a medial constriction; (iv) a rectangular ventral bar with short processes; (v) a triangular ventral bar membrane; and, most obviously, (vi) at least two generations which can develop two embryos simultaneously. This is the first known species of the genus Gyrodactylus from the Venezuelan Amazon and the first record of the subgenus Gyrodactylus (Gyrodactylus) from South America.  相似文献   
5.
The songs of 15 colour-marked, mated pairs of white-crowned sparrows (Zonotrichia leucophrys nuttalli) were recorded in a contact zone between the Presidio and San Francisco, California dialect regions. Males were recorded in the field and females were trapped after the breeding season and injected with testosterone to induce singing. The song of each member of a mated pair was classified using two different markers. It was found that most pairs did not match song types, and that the reproductive success of those that matched did not differ from those that did not match. Most of the territorial males sang the Presidio dialect, while most injected females sang the San Francisco dialect. The results fail to support a positive assortative mating hypothesis regarding the functional significance of learning dialects. It is suggested that the mismatching of songs could be due to sexual differences in the disposition to learn songs of neighbours at the breeding site.  相似文献   
6.
7.
We deleted exon 2 in human skeletal beta-tropomyosin (h beta-SK tropomyosin) using an improved adaptation of polymerase chain reaction (PCR) technology. The first PCR product was used to prime the full-length cDNA, leading to an exon 2-deleted h beta-SK tropomyosin. This new protein, des-(39-80)-tropomyosin, could then be expressed in Escherichia coli and purified to homogeneity. At the nucleotide level, the junction between exons 1 and 3 has been precisely made in the PCR product. The mutated protein was purified using high-performance liquid chromatography. Des-(39-80)-tropomyosin revealed new immunological properties but was still recognized by certain antitropomyosin antibodies. Furthermore, the structural characteristics of the mutated tropomyosin fit those of the full-length tropomyosin. This new adaptation of PCR technology appears to be suitable for every kind of mutation inside a cloned DNA molecule, and one mutation primer per mutation is sufficient.  相似文献   
8.
Atrioventricular (AV) and ventriculoatrial (VA) branches of the coronary arteries are vessels which supply simultaneously atrial and ventricular walls by means of recurrent rami. The terminology indicates the name of the main vessel followed by the name of the recurrent vessel both combined in an adjective. These branches establish a vascular 'suture' across the coronary sulcus in front (superficially to) or behind (deeply to) the trunks of the right coronary artery and of the left coronary artery (circumflex artery). The AV and VA branches, found in 95% of 40 human hearts, should be considered a normal characteristic of the coronary circulation and an important anatomical factor for the clinical interpretation of pathological cardiac phenomena.  相似文献   
9.
An efficient total synthesis of 1,5-di(trideuteromethyl)protoporphyrin-IX (3) dimethyl ester from monopyrrole precursors is described, the synthesis proceeding through crystalline tripyrrene and a,c-biladiene salt intermediates. The 2- and 4-vinyl groups in (3) are formed from the corresponding (2-chloroethyl) substituents by way of base-promoted dehydrochlorination. In protio solvents, this synthetic step is shown to exchange out preferentially deuterons in the 1-methyl group, and this observation is exploited in an efficient synthesis of the 1,3-di(trideuteromethyl)protoporphyrin-IX (22) dimethyl ester from 2,4-diacetyldeuteroporphyrin-IX (20) dimethyl ester (which is in turn accessible from commercially available protoporphyrin-IX (5)). Thus, basic exchange in deuterated solvent of (20) gives the deuterated analog, which after reduction and dehydration gives the 1,3-di(trideuteromethyl)protoporphyrin-IX analog (22), in which the vinyl H2 and propionic CH2·CO functions have also become deuterated.  相似文献   
10.
The primary structure of the two less acidic parvalbumins (pI = 5.44 and pI = 4.95) from coelacanth muscle (Latimeria chalumnae) has been determined. They differ only by the presence or absence of a N-terminal blocking group. By the use of the automatic degradation, 69 amino acids could be placed unambiguously in the N-terminal part and 24 amino acids following the single arginine 75. Tryptic peptides were used to establish the sequence and the position of the remaining residues. The two parvalbumins examined belong to the alpha-lineage, and the rate of their molecular evolution is comparable to that found in other vertebrates.  相似文献   
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