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71.
72.
The role of pRb2/p130 protein in diagnosing lung carcinoma on fine needle aspiration biopsies 总被引:2,自引:0,他引:2
Minimo C Bibbo M Claudio PP De Luca A Giordano A 《Pathology, research and practice》1999,195(2):67-70
The retinoblastoma gene family is composed of three members: the retinoblastoma gene, one of the most studied tumor suppressor genes, and two related genes: p107 and pRb2/p130. These proteins are also known as the pocket proteins due to a unique structural and functional domain composed of subdomains A and B separated by a spacer region that is highly conserved among each of the proteins. These proteins exhibit unique growth suppressive properties that are cell type specific, suggesting that although the pocket proteins may complement each other, they are not fully functionally redundant. With the development of antibodies recognizing these three proteins it is now possible to detect expression in formalin-embedded specimens. Recent studies on 235 lung cancers, using immunohistochemical techniques, suggested an independent role for Rb2/p130 in the development and/or progression of human lung carcinoma. We found a statistically significant inverse relationship between the histological grading (degree of malignant potential) and the expression of pRb/p105, p107 and pRb2/p130 in squamous cell carcinomas, meaning that an increase in grading resulted in a significant decrease in protein expression. This phenomenon was particularly evident for pRb2/p130 (p < .0001) which had the highest percentage of undetectable levels in all the specimens examined and the tightest inverse correlation (p value) with both the histological grading and PCNA expression in the most aggressive tumor types, suggesting an important role for pRb2/p130 in the pathogenesis and progression of certain lung cancers. We further explored the expression of pRb2/p130 protein in routine archival FNAB cytological material from 30 Patients with lung cancer using immunocytochemical techniques, comparing protein expression with tumor type. Two pathologists evaluated the staining pattern and scored the percentage of positive cells. Of the 30 neoplasms, 27 displayed a positive staining for pRb2/p130. In particular, we detected pRb2/p130 in 9 (100%) squamous carcinomas, 11 (84%) adenocarcinomas, 5 (100%) BAC, and 2 (66%) SCC. The percentage of positive nuclei varied in different tumors with the highest expression level in adenocarcinomas. Immunocytochemistry represents a sensitive method for detection of pRb2/p130 expression in cytological or archival specimens, and the level of detection seems to be comparable to paraffin sections. Therefore, this methodology could be used in the preoperative evaluation of routine cytological specimens in order to improve the diagnostic and prognostic evaluation of lung cancer patients. 相似文献
73.
A complex haemoglobinopathy diagnosis in a family with both beta zero- and alpha (zero/+)-thalassaemia homozygosity 总被引:2,自引:0,他引:2
Giordano PC Harteveld CL Bok LA van Delft P Batelaan D Beemer FA Bernini LF 《European journal of human genetics : EJHG》1999,7(2):163-168
The occurrence of point mutation alpha-thalassaemia and of complex combinations of haemoglobin defects is underestimated. Haemoglobinopathies, the most frequent monogenic recessive autosomal disorder in man, occur predominantly in Mediterranean, African and Asiatic populations. However, countries of immigration with a low incidence in the indigenous population, are now confronted with a highly heterogeneous array of imported defects. Furthermore, the occurrence of severe phenotypes is bound to increase in the near future because of the endogamous growth of the ethnical minorities and the lack of prevention. We describe an Afghan family in which both partners of a consanguineous relationship are carriers of a beta- as well as an alpha-thalassaemia determinant. The combination of defects was revealed by the in vitro measurement of the beta/alpha biosynthetic ratio and was characterised at the DNA level. The molecular defects involved are the Cd5(-CT), a Mediterranean beta zero-thalassaemia mutation, and the alpha 2(zero/+)-thalassaemia AATA(-AA) polyadenylation defect. The alpha-thalassemia defect is a rare RNA-processing mutant described only twice before in heterozygous form in Asian-Indian patients. The mutation suppresses the expression of a alpha 2 gene and reduces the expression of the less efficient, 3' located alpha 1 gene as well, inducing a near alpha zero-thalassaemia phenotype. This defect is now described for the first time in the homozygous condition in one of the children who, in addition to being homozygous for the alpha-thalassaemia point mutation, is also a carrier of the beta zero-thalassaemia defect. A previously described homozygous case of the alpha (zero/+)-thalassaemia condition, caused by a similar polyadenylation defect, was characterised by a severe HbH disease. However, the patient described here present at 7 years of age with severe caries, like his beta-thalassaemia homozygous brother but without hepatosplenomegaly, haemolysis or severe anaemia. The haematological analysis revealed 9.5 g/dl Hb; 5.4 x 10(12)/I RBC; 0.33 I/I PCV; 61 fl MCV; 17.6 pg MCH and 6.2% of HbA2. The biosynthetic ratio beta:alpha was 1.6 and no HbH fraction was detectable either on electrophoresis or as inclusion bodies. The parents reported no complications during pregnancy, at birth, or in the neonatal period in rural Afghanistan. We presume therefore that the counterbalancing effect induced by the co-existing beta-thalassaemia defect could have modified a potentially severe perinatal HbH disease into a strongly hypochromic but well compensated 'alpha zero-like heterozygous' thalassaemia phenotype. The risk of a severe HbH disease, could have been easily missed in this family which was referred because of a child affected with beta-thalassaemia major. 相似文献
74.
120 patients with progressive systemic sclerosis (PSS) were studied and subdivided into five groups according to the PSS classification of Giordano et al. ("acute diffuse scleroderma", "intermediate syndrome", "acrosclerosis sensu stricto", "sclerodactylia" and "sclerosis sine scleroderma"). In all five subgroups telangiectasias incidence was high (from 75% to 100%). The "ramosus" and "telangiectatic mats" types occur more frequently than other forms of telangiectasias. The former particularly involves the face, neck and chest; whereas the latter more usually involves the upper extremities and is the only type which appears at the lips. Cuticular telangiectasia is a third type, as important as the others but less frequent. The incidence of telangiectasias is related to disease duration. Similar telangiectasias have been observed in rarer patients with other connective tissue diseases (SLE, RA, dermatomyositis and undifferentiated connective tissue diseases). 相似文献
75.
A comparison of autografts and frozen, irradiated homografts in canine femoral venous reconstruction
Autogenous veins are the ideal substitute for bridging venous defects. Experimentally, fresh homografts have patency rates comparable to autografts. However, a method of preservation must be employed if homografts become practical for clinical use. In this study, homografts were frozen, irradiated, and stored for a total of 6 weeks. Following femoral venous reconstruction, patency rates between frozen, irradiated homografts and fresh autografts were compared and found to be similar over a 6 month period. Recanalization of the frozen, irradiated homografts occurred at the same rate as did that of the autografts. This study concludes that cryopreservation and irradiation are suitable methods of preservation that do not adversely affect patency. In addition irradiation will sterilize tissue and may decrease the potential of the graft to stimulate the recipient's immunologic system. 相似文献
76.
Aerial parts of SENECIO FILAGINOIDES yielded two new furanoeremophilane type sesquiterpenoids: 6alpha-acetyloxy-10betaH-furanoeremophil-1-one, 1 and 6alpha-tiglinoyloxy-10betaH-furanoerernophil-1-one, 2. Their structures have been elucidated by spectroscopic data. From roots and aerial parts of S. PINNATUS 1alpha-hydroxy-6betaangeloyloxy-10alphaH-furanoeremophil-9-one, 3 has been isolated. 相似文献
77.
"Effort" axillary-subclavian vein thrombosis (Paget-Schroetter syndrome) is an uncommon deep venous thrombosis due to repetitive activity of the upper limb. Clinical suspicion is usually confirmed by contrast venography. This report describes a case where the diagnosis was made by radionuclide venography (Tc-99m DTPA). The examination was carried out in the acute phase and clearly demonstrated the presence and the site of the obstruction as well as the collateral vessels. Despite a complete clinical recovery, obtained by medical therapy, further examinations performed in the follow-up period showed persistence of the thrombotic obstruction and a rich development of collateral vessels. In the authors' opinion, radionuclide venography is worth considering as a first-choice procedure when an axillary-subclavian vein thrombosis is suspected, and contrast venography should be performed only when surgical treatment is indicated. 相似文献
78.
The locomotor activity of C57B1/6J and DBA/2J mice was studied, under the influences of heroin, amphetamine, strychnine, or ethanol, and of combinations of the opiate with each one of the other drugs. Heroin treatment was followed by the typical running fit in the C57 mice, while the DBA strain was unaffected. Amphetamine enhanced the activity in the C57 strain only. The combination of heroin with amphetamine or ethanol increased the locomotor activity only in the DBA strain, while heroin + strychnine exerted a clear stimulating effect on the activity of the C57 mice. The strychnine + heroin mixture was more toxic than heroin alone when the lethal doses (LD50) were determined in the 2 strains. 相似文献
79.
Guglielmo Nasti Renato Talamini Andrea Antinori Ferdinando Martellotta Gaia Jacchetti Francesco Chiodo Giuseppe Ballardini Laura Stoppini Giovanni Di Perri Maurizio Mena Marcello Tavio Emanuela Vaccher Antonella D'Arminio Monforte Umberto Tirelli 《Journal of clinical oncology》2003,21(15):2876-2882
PURPOSE: To assess potential new prognostic factors and to validate the AIDS Clinical Trials Group (ACTG) for AIDS-related Kaposi's sarcoma (AIDS-KS) staging system in the highly active antiretroviral therapy (HAART) era. PATIENTS AND METHODS: We collected epidemiologic, clinical, staging, and survival data from 211 patients with AIDS-KS enrolled in two prospective Italian human immunodeficiency virus (HIV) cohort studies. We included in the analysis all patients with the diagnosis of KS made from January 1996, the time at which HAART became available in Italy. RESULTS: In the univariate analysis, survival was not influenced by sex, age, level of HIV viremia at KS diagnosis, HAART at KS diagnosis (HAART-na?ve v HAART-experienced), or type of HAART combination. Regarding ACTG classification, the 3-year survival rate was 85% for T0 patients and 69% for T1 patients (P =.007), 83% for S0 patients and 63% for S1 patients (P =.003), and 83% for I0 patients and 71% for I1 patients (P =.06). In the multivariate analysis, only the combination of poor tumor stage (T1) and poor systemic disease (S1) risk identified patients with unfavorable prognosis. The 3-year survival rate of patients with T1S1 was 53%, which was significantly lower compared with the 3-year survival rates of patients with T0S0, T1S0, and T0S1, which were 88%, 80%, and 81%, respectively (P =.0001). CONCLUSION: In the era of HAART, a refinement of the original ACTG staging system is needed. CD4 level does not seem to provide prognostic information. Two different risk categories are identified: a good risk (T0S0, T1S0, T0S1) and a poor risk (T1S1). 相似文献
80.
P Muretto F Graziano M P Staccioli I Barbanti A Bartolucci G Paolini D Giordano E Testa A De Gaetano 《Annals of oncology》2003,14(1):105-109
BACKGROUND: In gastric juice, high levels of the carcinoembryonic antigen (CEA) and the carbohydrate antigen 19-9 (CA 19-9) have been found to correlate with precancerous lesions and gastric cancer. So far, sampling of gastric juice has required upper endoscopy. In place of this invasive procedure, we investigated a new tool for the quantitation of tumor markers in gastric juice. MATERIALS AND METHODS: The study population consisted of healthy controls and consecutive subjects with suspected gastric cancer or dyspepsia/epigastric distress. Patients were asked to swallow a small gelatine capsule (14 mm in length and 5 mm in diameter) containing a pierced plastic cover and surrounding a piece of absorbent paper. The capsule was left in the gastric cavity for 60 min to allow saturation of the absorbent paper with gastric juice. A 45-50 cm length of nylon thread connected to the inner capsule was used to remove the device from the gastric cavity. After processing the absorbent paper for radioimmunoassay, CEA and CA 19-9 levels were correlated to the findings of upper endoscopy and biopsies of gastric mucosa or suspected lesions. RESULTS: The endogastric capsule did not cause any side-effects and 62 participants were fully compliant to the procedure. Assessable gastric juice samples were taken from 23 patients with gastric cancer, 15 patients with intestinal metaplasia or dysplasia, 12 patients with gastritis and 12 controls without gastric diseases. In the 12 samples of gastric juice from control patients, mean values of CEA and CA 19-9 were 1.1 +/- 0.9 ng/ml and 16 +/- 7.5 ng/ml, respectively. The mean levels of both markers were found to increase according to the severity of gastric lesions and in patients with cancer, mean CEA and CA 19-9 levels were 513 +/- 627 ng/ml and 545 +/- 510 ng/ml, respectively. Patients with precancerous lesions and cancer showed higher levels of CEA and CA 19-9 than patients with normal findings or gastritis (P <0.001). CONCLUSIONS: The endogastric capsule is a simple, non-invasive tool for the measurement of CEA and CA 19-9 levels in gastric juice. These values may discriminate between normal or minor pathologic changes and precancerous lesions or carcinomas. Further investigations are warranted, since this may represent a new method for gastric cancer screening. 相似文献