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981.
982.
BackgroundNatural killer (NK) cells derived from patients with cancer exhibit diminished cytotoxicity compared with NK cells from healthy individuals. We evaluated the tumor response and in vivo expansion of allogeneic NK cells in recurrent ovarian and breast cancerMethodsPatients underwent a lymphodepleting preparative regimen: fludarabine 25 mg/m2 × 5 doses, cyclophosphamide 60 mg/kg × 2 doses, and, in seven patients, 200 cGy total body irradiation (TBI) to increase host immune suppression. An NK cell product, from a haplo-identical related donor, was incubated overnight in 1000 U/mL interleukin (IL)-2 prior to infusion. Subcutaneous IL-2 (10 MU) was given three times/week × 6 doses after NK cell infusion to promote expansion, defined as detection of ≥100 donor-derived NK cells/μL blood 14 days after infusion, based on molecular chimerism and flow cytometryResultsTwenty (14 ovarian, 6 breast) patients were enrolled. The median age was 52 (range 30–65) years. Mean NK cell dose was 2.16 × 107cells/kg. Donor DNA was detected 7 days after NK cell infusion in 9/13 (69%) patients without TBI and 6/7 (85%) with TBI. T-regulatory cells (Treg) were elevated at day +14 compared with pre-chemotherapy (P = 0.03). Serum IL-15 levels increased after the preparative regimen (P = < 0.001). Patients receiving TBI had delayed hematologic recovery (P = 0.014). One patient who was not evaluable had successful in vivo NK cell expansionConclusionsAdoptive transfer of haplo-identical NK cells after lymphodepleting chemotherapy is associated with transient donor chimerism and may be limited by reconstituting recipient Treg cells. Strategies to augment in vivo NK cell persistence and expansion are needed.  相似文献   
983.
Abstract Screening of a Clostridium difficile ψEMBL3 gene library with antisera raised against C. difficile culture supernatant identified several clones expressing a 31-kDa protein. A 1.8-kb Hin dIII fragment subcloned from one of the clones was sufficient for expression of the 31-kDa polypeptide. Southern blot analysis showed a region homologous to this fragment to be present in all of 13 different C. difficile strains tested. Sequence analysis of the 1.8-kb fragment revealed three adjacent open reading frames. A database search showed that these three open reading frames appeared to encode homologues of three consecutive enzymes in the butanol/butyrate-producing pathway of Clostridium acetobutylicum (crotonase, β-hydroxybutyryl coenzyme A dehydrogenase and thiolase).  相似文献   
984.
We describe here a new type of X-linked liver glycogen storage disease. The main symptoms include liver enlargement and growth retardation. The clinical and biochemical abnormalities of this glycogenosis are similar to those of classical X-linked liver glycogenosis due to phosphorylase kinase deficiency (XLG). However, in contrast to patients with XLG, the patients described here have no reduced phosphorylase kinase activity in erythrocytes and leukocytes, and no enzyme deficiency could be found. Linkage analysis of four families with this X-linked type of liver glycogenosis assigned the disease gene to Xp22. Lod scores obtained with the markers DXS987, DXS207, and DXS999 were 3.97, 2.71, and 2.40, respectively, all at 0% recombination. Multipoint linkage analysis localized the disease gene between DXS143 and DXS989 with a maximum lod score of 4.70 at θ = 0, relative to DXS987. As both the classical XLG gene and the liver α-subunit of PHK (PHKA2) are also located in Xp22, this variant type of XLG may be allelic to classical XLG, and both diseases may be caused by mutations in PHKA2. Therefore, we propose to classify XLG as XLG type I (the classical type of XLG) and XLG type II (the variant type of XLG).  相似文献   
985.
X-Ray analysis of the ferritin of Escherichia coli (Ec-FTN) and of Ec-FTN crystals soaked in (NH4)2Fe(SO4)2 has revealed the presence of three iron-binding sites per subunit. Two of these form a di-iron site in the centre of the subunit as has been proposed for the ‘ferroxidase centres’ of human ferritin H chains. This di-iron site, lying within the 4-alpha-helix bundle, resemble those of ribonucleotide reductase, methane monoxygenase and haemerythrin. The third iron is bound by ligands unique to Ec-FTN on the inner surface of the protein shell. It is speculated that this state may represent the nucleation centre of a novel type of Fe(III) cluster, recently observed in Ec-FTN.  相似文献   
986.
The intracellular pathogenesis-related proteins have been identified in a broad range of flowering plants. Some display quite different patterns of expression, in many cases unrelated to the pathogenic response. Nevertheless, these proteins are all very similar and in most cases share more than 35% sequence identity. In this report we investigate the significance of a rather weak similarity between the intracellular pathogenesis-related (IPR or PR-10) proteins and a group of proteins identified in the latex of opium poppy and in Arabidopsis, among others. A sequence analysis held together with the recently published three-dimensional structure of Bet v 1, an IPR protein from birch pollen, strongly suggests sequential and structural homology between the two protein families.  相似文献   
987.
Estimates of daily energy expenditure are important for many areas of research in human ecology and adaptability. The most common technique for estimating human energy expenditure under field conditions, the factorial method, generally relies on activity-specific energy costs derived from published sources, based largely on North American and European subjects. There is concern that such data may not be appropriate for non-Western populations because of differences in metabolic costs. The present study addresses this concern by comparing measured vs. predicted energy costs at rest and during sub-maximal exercise in 83 subjects (52 males, 31 females) from three subsistence-level populations (Siberian herders and high-land and coastal Ecuadorian farmers). Energy costs at rest (i.e., lying, sitting and standing) and while performing a standard stepping exercise did not significantly differ among the three groups. However, resting energy costs were significantly elevated over predicted levels (+16% in men, +11% in women), whereas exercising costs were comparable to predicted values (?6% in men, +3% in women). Elevations in resting energy needs appear to reflect responses to thermal stress. These results indicate that temperature adjustments of resting energy costs are critical for accurately predicting daily energy needs among traditionally living populations. o 1996 Wiley-Liss, Inc.  相似文献   
988.
A highly sensitive enzymatic assay for diadenosine 5′,5?-P1,P3-triphosphate (Ap3A) has been established on the basis of the coupled luminescence assay for diadenosine 5′,5?-P1,P3-tetraphosphate (A. Ogilvie (1981)Anal. Biochem.115, 302–307). Snake venom phosphodiesterase splits Ap3A into AMP plus ADP which can be measured in a luminescence reaction containing pyruvate kinase, phosphoenolpyruvate and luciferin-luciferase. The procedure is linear with Ap3A levels ranging from 0.1 to 2 pmol. The assay has been used to measure Ap3A in various eukaryotic cells after ion-exchange chromatography and high-performance liquid chromatography of acidic extracts of the cells. The level of diadenosine triphosphate was higher in all instances than the level of diadenosine tetraphosphate. When growing in the abdominal cavity of mice, Ehrlich ascites tumor cells contained high amounts of Ap3A (0.1 nmol106cells), allowing direct optical determination in the HPLC chromatography. The quantitative measurement of Ap3A with the luminescence assay gave identical results. Ap3A extracted from Ehrlich cells was also chromatographed with authentic nucleotide in two thin-layer systems providing additional proof for the existence of Ap3A in biological material.  相似文献   
989.
Carpal tunnel syndrome (CTS) is an idiopathic disease that results from increased fibrosis of the subsynovial connective tissue (SSCT). A recent study found overexpression of both transforming growth factor-β (TGF-β) and connective tissue growth factor (CTGF) in the SSCT of CTS patients. This study investigated TGF-β and CTGF expression in a rabbit model of CTS, in which SSCT fibrosis is induced by a surgical injury. Levels of TGF-β1 and CTGF at 6, 12, 24 weeks after injury were determined by immunohistochemistry A significant increase in TGF-β1 and a concomitant significant increase in CTGF were found at 6 weeks, in addition to higher cell density compared to normal (all p<0.05), Interestingly, CTGF expression was reduced at 12 and 24 weeks, suggesting that an initial insult results in a time limited response. We conclude that this rabbit model mimics the fibrosis found in human CTS, and may be useful to study pathogenetic mechanisms of CTS in vivo.  相似文献   
990.
The ecology of the earthworm eel, Chendol keelini, was studied in the field over a period of nine months. In addition this information was supplemented by aquarium observations. The species was most abundant in pools where it was associated with leaf litter and mats of fine tree roots along the banks. It fed on benthic invertebrates, especially chironomid and ephemeropteran larvae. C. keelini is sexually dimorphic; adult males develop a headhump and grow to a larger size than females. Reproduction was seasonal; the reproductive phase coincided with the wet season and lasted for several months. Fecundity was around 40 eggs per clutch. The eggs were spherical, between 1.2 and 1.5mm in diameter, and possessed a pair of long filaments for adhesion to the substrate. Females probably spawned more than once during the breeding season. The length frequency distributions and juvenile growth suggest that C. keelini is a short-lived species that matures during the first year with few individuals surviving to the second breeding season.  相似文献   
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