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951.
Purpose This study was conducted to evaluate the diagnostic usefulness of gray level parameters in order to distinguish healthy bone from osteoblastic metastases on digitized radiographs. Materials and methods Skeletal radiographs of healthy bone (n = 144) and osteoblastic metastases (n = 35) were digitized using pixels 0.175 mm in size and 4,096 gray levels. We obtained an optimized healthy bone classification to compare with pathological bone: cortical, trabecular, and flat bone. The osteoblastic metastases (OM) were classified in nonflat and flat bone. These radiological images were analyzed by using a computerized method. The parameters (gray scale) calculated were: mean, standard deviation, and coefficient of variation (MGL, SDGL, and CVGL, respectively) based on gray level histogram analysis. Diagnostic utility was quantified by measurement of parameters on healthy and pathological bone, yielding quantification of area under the receiver operating characteristic (ROC) curve, AUC. Results All three image parameters showed high and significant values of AUC when comparing healthy trabecular bone and nonflat bone OM, showing MGL the best discriminatory ability (0.97). As for flat bones, MGL showed no ability to distinguish between healthy and flat bone OM (0.50). This could be achieved by using SDGL or CVGL, with both showing a similar diagnostic ability (0.85 and 0.83, respectively). Conclusion Our results show that the use of gray level parameters quantify healthy bone and osteoblastic metastases zones on digitized radiographs. This may be helpful as a complementary method for differential diagnosis. Moreover, our method will allow us to study the evolution of osteoblastic metastases under medical treatment.  相似文献   
952.
Four new HLA classical class I alleles in the three loci are described in Caucasian individuals. A*3012 was first suspected by an abnormal serologic pattern that would be explained by the single amino acid substitution at the A30-specific Ser17. B*270505 differs from B*270502 in a silent substitution at an up to now constant position in the B locus. B*3541 encodes for a new Cys at position 118 that has not been encountered in neither human nor primate alleles. Cw*0716 seems to be originated by a large-scale interallelic recombination event between Cw*0701/*0706/*0718 and Cw*020202, giving rise to a new antigen-binding cleft conformation.  相似文献   
953.
Insulin induces vasodilatation in human subjects and increases l-arginine transport and NO synthesis in human umbilical vein endothelial cells (HUVEC). Cell signalling events associated with insulin effects on activity and mRNA expression of the human cationic amino acid transporters 1 (hCAT-1) and 2B (hCAT-2B) are unknown. l-Arginine transport and eNOS activity were determined in HUVEC exposed to insulin. mRNA levels for hCAT-1, hCAT-2B and eNOS were quantitated by real time RT-PCR and endothelial NO synthase (eNOS) protein was identified by Western blot analysis. Intracellular Ca2+, l-arginine and l-citrulline levels, l-[3H]citrulline formation from l-[3H]arginine, cGMP formation, nitrite level, ATP release and membrane potential were determined. Insulin increased l-arginine transport and the mRNA levels for hCAT-1 and hCAT-2B and eNOS expression and activity. Insulin also induced membrane hyperpolarization and increased intracellular Ca2+, l-[3H]citrulline, cGMP and nitrite formation. Insulin-mediated stimulation of the l-arginine/NO pathway is thus associated with increased hCAT-1 and hCAT-2B mRNA, and eNOS expression, via mechanisms involving membrane hyperpolarization, mitogen-activated protein kinases p42 and p44, phosphatidylinositol 3-kinase, NO and protein kinase C. We have characterized a cell signalling pathway by which hyperinsulinaemia could lead to vasodilatation in human subjects, and which could have implications in patients in whom plasma insulin levels are altered, such as in diabetes mellitus.  相似文献   
954.
Hepatic silicosis was induced in rats by an intravenous injection of saline-suspended silica, 40 mg/kg of body weight. Changes in the liver were examined by biochemical, histological and histochemical methods. Infiltration of the liver parenchyma by polymorphonuclear leucocytes was observed only on the first day after silica treatment. Formation of silicotic nodules began on the first day by clustering of liver macrophages. A 22% increase in liver weight and a 67% increase in total liver DNA reflected accumulation of cells in the liver by day 28 after silica injection. Local cell division contributed to this increase. Almost all cells in the nodules contained carbon when the rats had been given ink before silica. Macrophages showed high activity of lysosomal esterases on the first few days after silica treatment; the activity disappeared later. Large granulomas containing hundreds of cells including lymphocytes were seen 226 days after treatment. Hydroxyproline content per gram of liver tissue increased by 35% and 58% by day 80 and 162, respectively. Connective tissue formed capsules around the nodules and grew to their inside. Activities of lysosomal enzymes, beta-D-galactosidase and acid proteases, in serum were increased by 20% and 300%, respectively, 35 days after treatment. Neither malondialdehyde concentration nor superoxide dismutase activity was elevated in silicotic liver.  相似文献   
955.
Many macrolides have been shown to affect the interaction between bacteria and various immune defense mechanisms, such as chemotaxis, accumulation, and bioactivity within phagocytic cells. The interaction of azithromycin with human polymorphonuclear leukocytes (PMNs) was studied in vitro and compared with the interactions between other macrolides and PMNs. The opsonophagocytic killing ofStaphylococcus aureus was synergistically enhanced by azithromycin at concentrations below and above the minimal inhibitory concentration, with a reduction of up to 2.82 log10 cfu/ml with 2 mg/ml of azithromycin. Other macrolides were effective only at subinhibitory concentrations. The beneficial azithromycin-leukocyte interaction may explain azithromycin's efficacy against intracellular pathogens.  相似文献   
956.
Systemically administered DNA encoding a recombinant human immunodeficiency virus (HIV) derived immunogen effectively primes a cytotoxic T lymphocyte (CTL) response in macaques. In this further pilot study we have evaluated mucosal delivery of DNA as an alternative priming strategy. Plasmid DNA, pTH.HW, encoding a multi-CTL epitope gene, was incorporated into poly(D,L-lactic-co-glycolic acid) microparticles of less than 10 microm in diameter. Five intrarectal immunizations failed to stimulate a circulating vaccine-specific CTL response in 2 Mamu-A*01(+) rhesus macaques. However, 1 week after intradermal immunization with a cognate modified vaccinia virus Ankara vaccine MVA.HW, CTL responses were detected in both animals that persisted until analysis postmortem, 12 weeks after the final boost. In contrast, a weaker and less durable response was seen in an animal vaccinated with the MVA construct alone. Analysis of lymphoid tissues revealed a disseminated CTL response in peripheral and regional lymph nodes but not the spleen of both mucosally primed animals.  相似文献   
957.
Papillon-Lefèvre syndrome (PLS) has recently been shown to be caused by mutations in the cathepsin C gene resulting in periodontal disease and palmoplantar keratosis. Thirteen different homozygous mutations have been characterised in PLS patients of different ethnic origin. In the present paper, a PLS patient is described who carries two novel mutations (706G>T and 872G>A) in the paternal and maternal chromosomes, respectively. This is the first compound patient described so far. In addition, a novel symptomless mutation (458C>T) in the cathepsin C gene is described in three homozygous individuals. Thus, not all mutations should be considered as a cause of disease, whether case studies or general population screening is performed. Another already described mutation that provoked the Haim-Munk syndrome (HMS) in Indian Jews has also been found to give rise to PLS in a Spanish family from Madrid. On the other hand, PLS patients are ameliorated by retinoids, which indicates that retinoids may be used as therapeutic agents in this immune system deficiency.  相似文献   
958.
We have determined the complete cDNA and deduced amino acid sequences of the heavy chain, regulatory light chain and essential light chain which constitute the molecular structure of myosin from the striated adductor muscle of the scallop, Pecten maximus. The deduced amino acid sequences of P. maximus regulatory light chain, essential light chain and heavy chain comprise 156, 156 and 1940 amino acids, respectively. These myosin peptide sequences, obtained from the most common of the eastern Atlantic scallops, are compared with those from three other molluscan myosins: the striated adductor muscles of Argopecten irradians and Placopecten magellanicus, and myosin from the siphon retractor muscle of the squid, Loligo pealei. The Pecten heavy chain sequence resembles those of the other two scallop sequences to a much greater extent as compared with the squid sequence, amino acid identities being 97.5% (A. irradians), 95.6% (P. magellanicus) and 73.6% (L. pealei), respectively. Myosin heavy chain residues that are known to be important for regulation are conserved in Pecten maximus. Using these Pecten sequences, we have overexpressed the regulatory light chain, and a combination of essential light chain and myosin heavy chain fragment, separately, in E. coli BL21 (DE3) prior to recombination, thereby producing Pecten regulatory domains without recourse to proteolytic digestion. The expressed regulatory domain was shown to undergo a calcium-dependent increase (7%) in intrinsic tryptophan fluorescence with a mid-point at a pCa of 6.6.  相似文献   
959.
Comorbidity measurements have recently been used to improve estimation of tolerance to allogeneic hematopoietic cell transplantation (HCT). We sought to determine the independent effect of comorbidity and performance status on HCT outcome and to devise a simple risk classification system for transplant-related mortality. We analyzed 105 consecutively enrolled patients who underwent HCT and received reduced intensity conditioning with fludarabine, melphalan, and alemtuzumab. Comorbid conditions were tabulated using 2 scales, the Charlson Comorbidity Index (CCI) and the Kaplan-Feinstein Scale (KFS). Comorbid conditions were found in 47% of patients by the KFS and in 27% by the CCI (P < .001). Using the Eastern Cooperative Oncology Group Performance Status (PS) scale, 34% had a PS score >0 (range, 0-2). A simple scale combining the KFS and PS enabled separation of high- from low-risk patients, with 6-month cumulative incidences 50% and 15%, respectively for transplant-related mortality (P = .001) and enhanced prognostic power over the CCI alone (P = .018). Prospective studies evaluating more comprehensive functional and comorbidity measurements are warranted.  相似文献   
960.
There are few reports about the incidence of the DeltaF508 mutation in Latin American countries. We show the study of the DeltaF508 mutation and the seven most common "European" mutations in 10 Ecuadorian CF affecteds. The incidence of DeltaF508 mutation found was 25% and none of the other seven was detected in our population, which indicates that at least 60% of the mutations in the studied population are different from most common in Europe. Similar data have been reported in other Amerindian populations, therefore it is suggested that Cystic Fibrosis in Ecuador-and other Amerindian countries in Latin America-have a different ethiology than that of Caucasian populations.  相似文献   
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