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1.
This paper reports the cosegregation in a three generation pedigree of dominantly inherited cataract with an abnormally high level of serum ferritin. In this family, circulating L ferritin was raised in all subjects affected by cataract independently of iron overload. We suggest that a disorder of ferritin metabolism could be a new genetic disorder leading to lens opacity. Cataract-hyperferritaemia syndrome could also be a new contiguous gene syndrome involving the L ferritin gene and the gene coding for the lens membrane protein (MP19), which both map to the same region of chromosome 19q.  相似文献   
2.
The pathways conferring immunity to human filariases are not well known, in part because human-pathogenic filariae do not complete a full life cycle in laboratory mice. We have used the only fully permissive infection of mice with filariae, i.e., infection of BALB/c mice with the rodent filarial nematode Litomosoides sigmodontis. Our previous results showed that worm development is inversely correlated with Th2 cytokine production and eosinophilia. The scope of the present study was to directly elucidate the role of interleukin-5 (IL-5) and eosinophils in controlling the development of L. sigmodontis after vaccination and in primary infection. BALB/c mice immunized with irradiated third-stage larvae (L3) were confirmed to have elevated IL-5 levels as well as high subcutaneous eosinophilia and to attack and reduce incoming larvae within the first 2 days, resulting in 70% reduction of worm load. Treatment of vaccinated mice with anti-IL-5 antibody (TRFK-5) suppressed both blood and tissue eosinophilia and completely abolished protection. This demonstrates, for the first time in a fully permissive filarial infection, that IL-5 is essential for protection induced by irradiated L3 larvae. In contrast, in primary-infected mice, anti-IL-5 treatment did not modify filarial infection within the 1st month, most likely because during primary infection IL-5-dependent mechanisms such as subcutaneous eosinophilia are induced too late to disturb worm establishment. However, there is a role for IL-5 late in primary infection where neutrophil-dependent worm encapsulation is also under the control of IL-5. Received: 30 March 2000  相似文献   
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BACKGROUND: We describe the production in Escherichia coli as a recombinant protein of clinical grade wild-type Bet v 1a (rBet v 1a), to be used as a candidate vaccine against birch pollen allergy. METHODS: This recombinant protein was purified by hydrophobic interaction and ion exchange chromatography and characterized by SDS-PAGE, immunoprint and circular dichroism in parallel with natural Bet v 1 (nBet v 1) purified from a birch pollen extract. We also compared rBet v 1 and nBet v 1 for their capacity to induce histamine release from basophils and to stimulate T lymphocyte proliferation. RESULTS: rBet v 1a appears in SDS-PAGE as an 18-kDa monomeric protein, whereas purified nBet v 1 comprises a mixture of isoforms (resolving as three distinct bands and six spots after 1-dimensional and 2-dimensional electrophoresis, respectively). Both recombinant and natural purified Bet v 1 molecules are recognized by IgE from birch pollen-allergic patients as well as anti-Bet v 1 murine monoclonal antibodies, suggesting that the recombinant protein is correctly folded in a native configuration. Circular dichroism analysis confirmed that the two Bet v 1 molecules exhibit similar 3-dimensional structures, even if rBet v 1a appears more compact and stable in thermodenaturation/renaturation experiments. Both rBet v 1 and nBet v 1 induce the degranulation of sensitized basophils and proliferation of Bet v 1-specific T lymphocytes in a similar manner. CONCLUSIONS: On the basis of these structural and biological properties, rBet v 1a is a valid candidate vaccine against birch pollen allergy, currently evaluated in humans.  相似文献   
4.
The Ysc-Yop type III secretion (TTS) system allows extracellular Yersinia bacteria, adhering to eukaryotic target cells, to inject Yop effector proteins in the cytosol of these cells. The secretion apparatus, called the injectisome, ends up with a needle-like structure made of YscF. YopN, one of the proteins secreted by the injectisome is thought to act as a plug. YopB, YopD and LcrV, three other proteins secreted by the injectisome and called 'translocators' form a pore allowing translocation of the Yop effectors across the target cell plasma membrane. Here, we tested the role of LcrV, YscF and YopN in the formation of this pore in macrophages by monitoring the release of the low-molecular-weight fluorescent dye BCECF (2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester, 623Da) and of the high-molecular-weight lactate dehydrogenase (LDH, 135 kDa). BCECF is released through the translocation pore itself provided no Yop effector is trafficking through the channel. In contrast, LDH is released by the osmotic lysis of the target cell that occurs after pore formation. This release is reduced by the GAP activity of YopE. In order to study the role of LcrV, one has to circumvent the regulatory effect of LcrV on the synthesis of YopB and YopD. We observed here that this regulatory role of LcrV is lost in a yopQ mutant and hence we studied the role of LcrV in a yopQ mutant background. A lcrV, yopQ double mutant was deficient in pore formation while able to produce YopB and YopD. Pore formation was restored by the introduction of lcrV(+) but not yopQ(+) confirming that LcrV itself is directly required for pore formation. Bacteria secreting only YopB, YopD and LcrV could form pores, showing that YopB, YopD and LcrV are sufficient for pore formation provided they are secreted by the same bacterium. LcrV is not involved in secretion of YopB and YopD as suggested previously. Bacteria producing normal Ysc injectisomes, including the YscF needle but no translocators did not form pores, indicating that the needle is not sufficient by itself for pore formation, as was also suggested. yopN mutant bacteria formed needles and released BCECF even if they secreted the effectors. This observation suggests that many translocation pores are not filled in the absence of YopN and thus that YopN might form a link between the needle and the pore, guiding the effectors.  相似文献   
5.
Percutaneous radiologic gastrostomy (PRG) requires preliminary gastric inflation through a nasogastric tube (NGT) to safely perform gastric puncture. However, in case of pharyngeal or esophageal obstruction, NGT placement may be impossible even with a hydrophilic angiography catheter and wire. This brief report describes percutaneous computed tomography (CT)–guided gastrostomy with a 2-stick approach without nasogastric insufflation in 13 patients. Technical success rate was 100% with a mean of 1.8 punctures ± 1.0 to access the gastric lumen. Traversal of the colon and liver with a 22-gauge needle was necessary in 4 and 1 patients, respectively. There were no major complications. Minor complications occurred in 6 patients (46%). CT-guided percutaneous gastrostomy is technically feasible with minimal morbidity.  相似文献   
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Our purpose was to determine the respective prognostic significance of CD105 and CD31 immunoexpression in node negative patients with breast carcinoma, since angiogenesis induces blood borne metastases and death in carcinomas. CD105 (endoglin) has been reported as expressed by activated endothelial cells and consequently should better reflect neoangiogenesis in malignant tumors. Comparison of CD31 and CD105 immunocytochemical expression was undertaken in a series of 905 breast carcinomas. Results were compared to patients' long-term (median = 11.3 years) outcome. Univariate (Kaplan-Meier) analysis showed that the number of CD105+ microvessels (cut-off 15 vessels) correlated significantly with poor overall survival (p=0.001). This correlation was less significant in node negative patients (p=0.035). The number of CD31+ microvessels (cut-off 25 vessels) similarly correlated with poor survival (p=0.032) but not in the subgroup of node negative patients. Marked CD105 expression also correlated with a high risk for metastasis in all patients (p=0.0002) and in the subset of node negative patients (p=0.001). Similarly metastasis risk in node negative patients correlated with marked CD31 immunocytochemical expression (p=0.02). Multivariate analysis (Cox model) identified CD105, but not CD31 immunoexpression, as an independent prognostic indicator. Our results suggest that: i) in breast carcinomas, immunoselection of microvessels containing activated CD105 labelled endothelial cells is endowed with a stronger prognostic significance, as compared to CD31 vessels labelling; ii) the CD105 immunoexpression may be considered as a potential tool for selecting node negative patients with a poorer outcome and higher metastasis risk; iii) in these patients specific antiangiogenic therapy targeted by anti-CD105 conjugates can be further developed.  相似文献   
10.
Nocardia veterana is a recently characterized species within the genus Nocardia, and only three human clinical isolates have been reported for this species. We describe a case of ascitic fluid infection in an immunocompromised patient due to N. veterana. To our knowledge, this is the first report of a Nocardia sp. strain from ascitic fluid and the fourth report of N. veterana isolated from human samples. Chemotaxonomic methods showed the strain to belong to the genus Nocardia, and identification to the species level was done by 16S ribosomal DNA gene sequencing. The antibiotic susceptibility profile of N. veterana is reported here for the second time. The strain was deposited in the Collection of the Pasteur Institute and in the Culture Collection of the University of G?teborg (CIP 107497 and CCUG 46576). The corresponding 16S ribosomal DNA gene sequence is available from the GenBank database under accession number AY149599. A phylogenetic analysis was conducted and showed that N. veterana was most closely related to the recently characterized species Nocardia africana rather than to Nocardia vaccinii, as previously reported.  相似文献   
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