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11.
The distribution of eight putative adhesins that are not encoded in the locus for enterocyte effacement (LEE) in 139 Shiga toxin-producing Escherichia coli (STEC) of different serotypes was investigated by PCR. Five of the adhesins (Iha, Efa1, LPF(O157/OI-141), LPF(O157/OI-154), and LPF(O113)) are encoded in regions corresponding to genomic O islands of E. coli EDL933, while the other three adhesins have been reported to be encoded in the STEC megaplasmid of various serotypes (ToxB [O157:H7], Saa [O113:H21], and Sfp [O157:NM]). STEC strains were isolated from humans (n = 54), animals (n = 52), and food (n = 33). They were classified into five seropathotypes (A through E) based on the reported occurrence of STEC serotypes in human disease, in outbreaks, and in the hemolytic-uremic syndrome (M. A. Karmali, M. Mascarenhas, S. Shen, K. Ziebell, S. Johnson, R. Reid-Smith, J. Isaac-Renton, C. Clark, K. Rahn, and J. B. Kaper, J. Clin. Microbiol. 41:4930-4940, 2003). The most prevalent adhesin was that encoded by the iha gene (91%; 127 of 139 strains), which was distributed in all seropathotypes. toxB and efa1 were present mainly in strains of seropathotypes A and B, which were LEE positive. saa was present only in strains of seropathotypes C, D, and E, which were LEE negative. Two fimbrial genes, lpfA(O157/OI-141) and lpfA(O157/OI-154), were strongly associated with seropathotype A. The fimbrial gene lpfA(O113) was present in all seropathotypes except for seropathotype A, while sfpA was not present in any of the strains studied. The distribution of STEC adhesins depends mainly on serotypes and not on the source of isolation. Seropathotype A, which is associated with severe disease and frequently is involved in outbreaks, possesses a unique adhesin profile which is not present in the other seropathotypes. The wide distribution of iha in STEC strains suggested that it could be a candidate for vaccine development.  相似文献   
12.
Sarcoglycanopathies are a genetically heterogeneous group of autosomal recessive muscular dystrophies in which the primary defect may reside in any of the genes coding for the different partners of the sarcolemmal sarcoglycan (SG) complex: the alpha-SG (LGMD2D at 17q21.2), the beta-SG (LGMD2E at 4q12), the gamma-SG (LGMD2C at 13q12), and the delta-SG (LGMD2F at 5q33). We report a series of 20 new unrelated families with 14 different mutations in the alpha-SG gene. Along with the mutations that we previously reported this brings our cohort of patients with alpha-sarcoglycanopathy to a total of 31 unrelated patients, carrying 25 different mutations. The missense mutations reside in the extracellular domain of the protein. Five of 15 missense mutations, carried by unrelated subjects on different haplotype backgrounds and of widespread geographical origins, account for 58% of the mutated chromosomes, with a striking prevalence of the R77C substitution (32%). The severity of the disease varies strikingly and correlates at least in part with the amount of residual protein and the type of mutation. The recurrent R284C substitution is associated with a benign disease course.  相似文献   
13.
A Congo red-magnesium oxalate agar medium was developed to detect expression of virulence-associated calcium dependency and Congo red absorption in Yersinia enterocolitica. Of the 157 pathogenic serotypes tested, 119 (75.8%) were positive; 98% of nonpathogenic serotypes and strains of three other Yersinia species were negative.  相似文献   
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Fourteen patients with advanced soft tissue sarcomas (STS), all pre-treated with one or more chemotherapy (CT) lines, entered an outpatient phase 11 study in which subcutaneous recombinant Interleukin-2 (rIL-2) and intramuscular recombinant alpha-2a-interferon (r-alphaIFN) were concomitantly administered. Both the cytokines were given for 5 days/week for 3 consecutive weeks followed by a 2 weeks period during which only r-alphaIFN was administered. r-alphaIFN was provided at a dose of 3 x 10(6) International Units (IU), while rIL-2 was given at a dosage of 6 x 10(6)/m2/day IU (in 2 subcutaneous injections), starting from 2 x 10(6)/m2/day IU in the first week and progressively increasing to 4 and 6 x 10(6)/m2/day IU in the second and third weeks; in 4 patients the dose of 8 x 10(6)/m2/day IU was reached. Toxicity was moderate and correlated with rIL-2 dose; main side effects included changes in liver functionality tests (14/14), fever (13/14), fatigue (13/14), nausea and vomiting (9/14). In all 11 patients evaluable for response, stable disease (SD) was observed (duration 4-43 weeks; median 9 weeks); the median survival from the starting treatment was 18 weeks (range 10-52). In all treated patients, an immunological monitoring was performed: an increase in percentage (from 10 to 74%) and in absolute number (from 400 to 4.500 cells/mm3) of CD16+ lymphocytes (NK cells) was observed in the majority of cases. Our data indicate that this regimen can be administered in pre-treated and severely immunocompromised patients with minimal to moderate toxicity on ambulatory and home bases, with acceptable clinical results.  相似文献   
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1. We studied the effect of intracellular angiotensin II (Ang II) and related peptides on rat aortic contraction, whether this effect is pharmacologically distinguishable from that induced by extracellular stimulation, and determined the Ca2+ source involved. 2. Compounds were delivered into the cytoplasm of de-endothelized aorta rings using multilamellar liposomes. Contractions were normalized to the maximum obtained with phenylephrine (10(-5) M). 3. Intracellular administration of Ang II (incorporation range: 0.01-300 nmol mg(-1)) resulted in a dose-dependent contraction, insensitive to extracellular administration (10(-6) M) of the AT1 receptor antagonist CV11947, the AT2 receptor antagonist PD 123319, or the non-selective AT receptor antagonist and partial agonist saralasin ([Sar1,Val5,Ala8]-Ang II (P<0.05). 4. Intracellular administration of CV11947 or PD 123319 right shifted the dose-response curve about 1000 fold or 20 fold, respectively. PD 123319 was only effective if less than 30 nmol mg(-1) Ang II was incorporated. 5. Contraction was partially desensitized to a second intracellular Ang II addition after 45 min (P<0.05). 6. Intracellular administration of Ang I and saralasin also induced contraction (P<0.05). Both responses were sensitive to intracellular CV11947 (P<0.05), but insensitive to PD 123319. The response to Ang I was independent of intracellular captopril. 7. Contraction induced by extracellular application of Ang II and of Ang I was abolished by extracellular pre-treatment with saralasin or CV11947 (P<0.05), but not with PD 123319. Extracellular saralasin induced no contraction. 8. Intracellular Ang II induced contraction was not affected by pre-treatment with heparin filled liposomes, but completely abolished in Ca2+-free external medium. 9. These results support the existence of an intracellular binding site for Ang II in rat aorta. Intracellular stimulation induces contraction dependent on Ca2+-influx but not on Ins(1,4,5)P3 mediated release from intracellular Ca2+-stores. Intracellular Ang I and saralasin induce contraction, possibly via the same binding site. Pharmacological properties of this putative intracellular receptor are clearly different from extracellular stimulated AT1 receptors or intracellular angiotensin receptors postulated in other tissue.  相似文献   
19.
A series of pyrrolo[3,2-c]quinoline derivatives were synthesised and evaluated as inhibitors of selected enzymes of the kynurenine pathway. 7-Chloro-3-methyl-1H-pyrrolo[3,2-c]quinoline-4-carboxylic acid (7a) was found to be a relatively potent and selective inhibitor of kynurenine-3-hydroxylase (KYN-3-OHase). A molecular modelling study showed a good superimposition of 7a with PNU-156561 and kynurenine the natural substrate of KYN-3-OHase.  相似文献   
20.
Multiple carcinoid tumors of the small bowel with more than 3 lesions are very unusual. The authors report a case with 4 lesions, 2 of those localized in the jejunum with more advanced infiltration of the wall and extension to regional mesenteric lymph nodes, revealed by ultrasonography. The relative low incidence and particularly the vague, nonspecific clinical presentation, the unusual site in the jejunum, and failure of the radiological examine of one year before lead to not suspect this condition prior to US examination. However, the feature of asymmetric, concentric thickening of the bowel wall requiring a more accurate exam by CT with oral contrast was able to confirm the suspect of the intestinal tumor. The patient, 80 year old, underwent radical surgery with a wide lymph nodes dissection as well as double resection of the jejunum and distal ileum. The post-surgical outcome was uneventful. A 12-month follow-up is free of the disease.  相似文献   
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