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1.
Abstract: We analyzed the expression of CEA, CA19-9, CA125, CA15-3 (DF3), PCNA and p53 immunohistochemically in 14 tissue specimens of mucosal cancers in adenoma, seven tubulovillous adenoma specimens, and 16 tubular adenoma specimens. The rates of positive staining for mucosal cancer in adenoma, tubulovillous adenoma and tubular adenoma specimens, respectively, were: for CEA: 100%, 85.7% and 75%; for CA19-9: 71.4%, 71.4% and 56.2%; for CA125:0%, 0% and 0%;for CA15-3 (DF3): 64.3 %, 0% and 0 %; for PCNA: 100%, 88.9% and 56.2%; and for p53: 35.7%, 0% and 0% . The results suggest that the expressions of CEA, CA19-9, CA15-3 (DF3), PCNA and p53 are related to colorectal tumorigenesis. None of the specimens studied showed staining for CA125, suggesting that CA125 is not involved in the early stages of colorectal carcinogenesis. There was no significant difference in the rates of positive staining for CEA and CA19-9 among mucosal cancer in adenoma, tubular adenoma and tubulovillous adenoma specimens. However, the rates of positive staining for PCNA and p53 were significantly higher in mucosal cancer in adenoma specimens than for tubular adenoma specimens (p<0.05), and the rate of CA15-3 (DF3) positive staining was significantly higher for mucosal cancer in adenoma than for tubulovillous adenoma (p<0.01) and tubular adenoma (p< 0.001) specimens. Therefore, the CA15-3 (DF3) antigen is an immunohistochemical marker for colorectal carcinomas. The present results suggest that CA15-3 (DF3), PCNA and p53 play important roles in the genesis of colorectal adenomas. 相似文献
2.
H. W. Chu S. Balzar J. Y. Westcott J. B. Trudeau Y. Sun D. J. Conrad S. E. Wenzel 《Clinical and experimental allergy》2002,32(11):1558-1565
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels. 相似文献
3.
Anders Persson Stefan Pauli Christer Halldin Sharon Stone-Elander Lars Farde Irene Sjgren Gran Sedvall 《Human psychopharmacology》1989,4(1):21-31
The 11C-labelled benzodiazepine antagonist Ro 15–1788 (flumazenil) and positron emission tomography (PET) were used to determine quantitative characteristics of benzodiazepine receptor binding in the neocortex of healthy young men. Saturating doses of unlabelled flumazenil administered i.v., before or together with the ligand-reduced 11C-flumazenil accumulation in the neocortex by about 90 per cent. Saturating doses of unlabelled flumazenil had little effect on the accumulation of radioactivity in the benzodiazepine receptor-poor regions such as pons or white matter. By giving graded doses of unlabelled flumazenil together with the tracer, saturation isotherms were obtained allowing the calculation of receptor density (Bmax) and equilibrium dissociation constant (Kd) values on the basis of certain assumptions Bmax values were in the order of 90 pmol/g and Kd values in the order of 10 nM in the neocortex. Scatchard and Hill plots of the radioactivity data indicated that 11C-flumazenil binds to saturable sites of a homogeneous population. The data indicate that intravenous doses of 1 or 2 mg flumazenil result in a benzodiazepine receptor occupancy of about 50 per cent. The method described should be useful for studying regional differences in benzodiazepine receptor characteristics in the living human brain in healthy subjects and neuropsychiatric disorders, and also in relation to treatment with drugs interacting with benzodiazepine receptors. 相似文献
4.
Background: The Farnsworth D15 test is designed to categorise colour vision deficiency as severe or moderate. The level of difficulty of the test was set so that those who passed it should be able to recognise surface colour codes, such as those used for electrical wiring. The test is widely used to provide advice to patients with abnormal colour vision and is often used for occupational selection when reliable recognition of surface colour codes is required. However, there has been only one previous study of the correlation between performance at the D15 test and the naming of surface colour codes and there has been no study of whether a person who passes the D15 can reliably name surface colours. Methods: One hundred and two people aged 11 to 65 years with abnormal colour vision were recruited from consecutively presenting optometric patients and were asked to name the colours of fabric, paint and cotton thread samples. There were 10 colours in each class of material and the samples were presented in a large (five to 10 degree angular subtense) and small size (2.5 deg and a single thread). The errors made were compared to those made by an age‐matched control group of equal size with normal colour vision. Results: The correlations between the Farnsworth D15 colour confusion index and colour naming errors were 0.62 for the large stimuli and 0.73 for the small stimuli. Its sensitivity and specificity identifymg those who made more errors than the worst performing colour normal person were 0.80 and 0.69 (large stimuli) and 0.75 and 0.71 (small stimuli). A Nagel anomaloscope range of less than 35 scale units provides essentially the same sensitivity and specificity. Conclusions: About 40 per cent of those with abnormal colour vision can name the main colours correctly under good visibility conditions. The D15 test is an imperfect predictor of those who can name surface colour codes correctly but it does provide useful information for general counselling. It is not suitable as a single test for occupational selection because it will pass 20 per cent who cannot name surface colours correctly and fail 30 per cent who can. In occupations in which recognition of surface colour codes is of critical importance, it may be best not to select people with abnormal colour vision because of the lack of a colour vision test that is a perfect predictor of the ability to recognise surface colours. 相似文献
5.
K. Mörike M. Koch Peter Fritz Wolfgang Urban Michel Eichelbaum 《Archives of toxicology》1996,70(5):300-305
In the pathogenesis of isoniazid-induced hepatic injury, cytochrome P450-dependent metabolic activation of the metabolite,
acetylhydrazine (AcHz), is the crucial step. Exhalation of [14C]-carbon dioxide has previously been used to quantify indirectly this pathway. In contrast, according to the current concept
of AcHz bioactivation, molecular nitrogen is produced directly, but has not yet been identified. Here, we measured [15N]-nitrogen and 14CO2 exhalation, after the administration of [15N2]-[14C]-AcHz, in rats. Laser magnetic resonance (LMR) spectroscopy, a new sensitive and specific technique for the measurement
of 15N and 14N in gas samples, was used. To demonstrate the involvement of cytochrome P450, rats were treated with phenobarbital (PB) or
PB + cobalt(II) chloride (CoCl2) (n=3 in each group). Time-dependent 15N2 exhalation differed significantly between treatment groups (p<0.001). At 240 min, cumulative exhalation of 15N was 1.92±0.43% (mean±SE) of the dose in the control group, 2.53±0.23% in the PB group, and 1.00±0.15% in the PB+CoCl2 group (p<0.05 compared to controls, p<0.01 compared to PB). Cumulative exhalation of 14CO2 in 24 h ranged from 15.1 to 21.9%, with no significant difference between treatment groups. In conclusion, N2 is a metabolite of AcHz. N2 formation reflects the cytochrome P450-mediated activation of AcHz and can be used as an index of this pathway. Generally,
LMR spectroscopy is valuable for monitoring any N2-liberating process in vivo.
Received: 14 March 1995/Accepted: 15 August 1995 相似文献
6.
Yayoi S. Kikkawa Karen S. Pawlowski Charles G. Wright Kumar N. Alagramam 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(2):224-232
The Ames waltzer (av) mouse mutant harbors a mutation in the protocadherin 15 gene (Pcdh15) and is a model for deafness in Usher syndrome 1F and nonsyndromic deafness DFNB23. Mutation in Pcdh15 affects stereocilia morphogenesis and polarity. Disruptions of apical cellular components in outer hair cells have also been described in av mutants. Organization of stereocilia and cell polarization may be dependent on proper orientation of structural components residing in the apical portion of the cell during development. We used electron and immunofluorescent microscopy to examine structural maturation of outer hair cells in av3J mice with emphasis on the fonticulus, basal body/centriole complex, actin mesh, and the microtubule network during initiation of bundle organization, between embryonic day (E) 16.5 and postnatal day 5 (P5). We found major ultrastructural rearrangements near the hair cell surface in av3J mice. Earliest changes were in kinocilia, basal body, and stereocilia positioning and microtubule arrangement once the kinocilia had lateralized to the side of the cell (between E16.5 and postnatal day [P] 0, before cuticular plate formation and stereocilia elongation). By P0, the developing fonticulus in av mice appeared enlarged, with a normal vesicle density. Stereocilia bundle disorganization increased after P0, with disruptions of the actin mesh within the cuticular plate. These observations support the hypothesis that mutations in Pcdh15 in av3J mice adversely affect coordinated maturation of apical cell components, resulting in disturbed stereocilia bundle polarity in av mice. Anat Rec, 2007. © 2008 Wiley‐Liss, Inc. 相似文献
7.
L. D. Bornemann H. E. Spiegel Z. E. Dziewanowska S. E. Krown W. A. Colburn 《European journal of clinical pharmacology》1985,28(4):469-471
Summary Interferon is currently being evaluated for the treatment of disseminated cancer and viral diseases. Alpha interferons have shown to be effective in the treatment of a number of malignancies. Recombinant leukocyte A interferon (rIFN-A) is an alpha interferon produced by recombinant DNA techniques. A kinetic evaluation of rIFN-A following intravenous and intramuscular administration has not been adequately defined. The present study was designed to evaluate the kinetics of rIFN-A following intravenous and intramuscular administration of 3, 9 or 18×106 units to patients with disseminated cancer.A preliminary report of this study was presented at the meeting of the American Society for Clinical Pharmacology and Therapeutics in San Diego, March 1983 (1). 相似文献
8.
E. Zanette L. Bozzao C. Buttinelli A. Mariottini S. Pappatà G. L. Lenzi 《Acta neurochirurgica》1987,89(1-2):43-47
Summary Tumour growth essentially requires fibrin formation and fibrinopeptide A (FPA) is liberated into the circulation on fibrin formation. In the present study, a possible elevation of serum FPA level was examined in patients with metastatic brain tumour. A significant elevation of serum FPA level was shown in all 6 patients with metastatic brain tumour, when blood was drawn from the internal jugular vein. It was extremely high in 2 patients with rapidly growing tumour. However, such a significant elevation was not shown in 3 cancer patients without brain metastasis or in 1 patient with a huge meningioma. This suggests the possibility that the presence of metastatic brain tumour could be detected by measuring FPA in blood drawn form the internal jugular vein. This also suggests the tendency that elevation of serum FPA is higher in patients with more rapidly growing tumour.Infusion of urokinase into the internal carotid artery resulted in an elevation of serum fibrinopeptide B (1)15–42 (FPB) in 5 patients with metastatic brain tumour, when blood was drawn from the internal jugular vein. This suggests that urokinase could induce fibrinolysis in the tumour tissue, though this remains in conclusive because of the lack of complete controls. 相似文献
9.
A novel method of preparing small-sized microcapsules using a Turbotak air-atomizer is reported. Alginate-polylysine microcapsules containing Bacillus Calmette Guérin vaccine have been prepared by an adaptation of the method of Lim (1) which allows the manufacture of small-sized microcapsules. A Turbotak is used to spray sodium alginate solution into calcium chloride solution to form temporary calcium alginate microgel capsules. These temporary microgel droplets are subsequently cross-linked with polylysine to form permanent membranes. Microcapules in the size range of 5–15 µm have been produced which can be compared to an average diameter of 300 µm obtained by the method reported by Lim. The microcapsule size is dependent on the conditions of operation of the Turbotak and the concentration of the sodium alginate solution. Particles within the size range 5–15 µm can be reproducibly manufactured using the conditions of operation reported here. Other size ranges below the minimum of 300 µm reported by Lim are also feasible using this technique. 相似文献
10.
T.W.‐M. Fan A.N. Lane E. Chekmenev R.J. Wittebort R.M. Higashi 《Chemical biology & drug design》2004,63(3):253-264
Abstract: Soil humic substances (HS) are heterologous, polydispersive, and multi‐functional organometallic macromolecules ubiquitous in soils and sediments. They are key players in the maintenance of the belowground ecosystems and in the bioavailability of both organic and inorganic contaminants. It is widely assumed that the peptidic substructures of HS are readily degraded and therefore do not contribute significantly to interactions with contaminants such as toxic metals. To investigate the turnover of humified peptides, laboratory soil aging experiments were conducted with 13C‐glucose or 15N‐nitrate for 8.5 months. Evidence for random‐coil peptidic structures in the labeled HS was obtained from 2‐D nuclear magnetic resonance (NMR), pyrolysis gas chromatography‐mass spectrometry (pyro‐GC‐MS), and circular dichroism data. Interaction of metals with the peptidic carbonyls of labeled HS was rationalized from the solid‐state NMR data. Detailed 13C and 15N labeling patterns of amino acid residues in the acid hydrolysates of HS acquired from NMR and GC‐MS revealed two pools of peptides, i.e. one extant (unlabeled) and the other, newly humified with little isotopic scrambling (fully labeled). The persistence of pre‐existing peptidic structures indicates their resistance to degradation while the presence of fully labeled peptidic amino acids suggests wholesale incorporation of newly synthesized peptides into HS. These findings are contrary to the general notion that humified peptides are readily degraded. 相似文献