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961.
AIM: To investigate the immunocytochemical staining pattern of mdm2 and p21WAF1 proteins in invasive cervical cancer and to determine its relation with the expression of p53 and with the high risk HPV infection. METHODS: Immunocytochemistry for p53, mdm2, and p21WAF1 was performed in 31 paraffin embedded sections of invasive cervical cancer. The results were assessed by image analysis, evaluating for each protein the optical density of the immunostained area, scored as percentage of the total nuclear area. The presence of high risk human papillomavirus (HPV) infection was detected by using the polymerase chain reaction. RESULTS: Immunostaining for both mdm2 and p21WAF1 was correlated with p53 expression; however, the correlation between p53 and mdm2 (R = 0.49; p < 0.01) was more significant than between p53 and p21WAF1 (R = 0.31; p < 0.05); the less stringent correlation between p53 and p21WAF1 might reflect the p53 independent mechanisms of p21WAF1 induction. Similar average levels of p53, mdm2, and p21WAF1 immunostaining were found in the presence or absence of high risk HPV-DNA, without significant differences between the two groups. CONCLUSIONS: These data suggest that mdm2 and p21WAF1 proteins are expressed in invasive cervical cancer and that their immunocytochemical staining pattern is not abrogated by the presence of high risk HPV genomic sequences.  相似文献   
962.
Various techniques are used to collect specimens from the nasal mucosa for morphologic and biochemical analysis. The purpose of this study was to devise a method that overcomes some of the disadvantages (e.g., invasive procedure, samples not suitable for cytologic and biochemical analysis, lack of standardization, and poor reproducibility) of these techniques. The new method requires subjects, with neck extended, to inhale an ultrasonic nebulization of a hypertonic (3% NaCl) solution (UNHS) for 5 min. They then blow their nose into a Petri dish, one nostril at a time with the other one blocked. The secretions are dispersed with 0.1% dithiothreitol in phosphate buffer solution for 20 min. Total cell count (TCC) is evaluated, and the cellular suspension is divided into two aliquots: one is centrifuged and the supernatants are collected for eosinophil cationic protein (ECP) measurements; the other is cytocentrifuged and the slides, stained with Diff-Quik, are used for differential cell count. The results obtained with the UNHS and nasal lavage (NL) methods were compared. Eleven nonatopic healthy subjects and 19 allergic rhinitic patients were studied. Total cell count (×105) was significantly higher with UNHS than with NL (13.0±12.3 vs 1.911.6; P<0.0]) The differential cell count was similar with the two procedures. ECP levels (μg/l) were higher with UNHS than with NL (39.1+38.2 V.S 16.7±41.2; P<0.01). For evaluation of reproducibility, four healthy and six rhinitic subjects underwent UNHS on two occasions within 5 days, and the results of two samples (sample 1 vs sample 2) were analyzed. Reproducibility was good as to TCC, differential cell count, and ECP  相似文献   
963.
The principal result of the development of hemovigilance since 1994 has been the declaration of undesirable effects likely to be due to transfusions of labile blood products. Using the 1694 cases of undesirable effects registered, it seemed worthwhile to us to analyze the distribution of the signs noticed, their frequency and the types of blood products responsible. This analysis allowed us to observe that the majority of reactions were shivery-feverish (47%) or allergic (24%). Most of them are linked to platelet concentrate transfusions especially simple donor platelets (with a frequency of ten reactions for thousand apheresis platelet concentrates transfused).In this study the frequency of undesirable effects reported is 2 per 1000 apheresis platelet concentrate transfusions. Further investigations are necessary to determine the physiological mechanisms of these reactions and to estimate the degree to which transfusions are responsible for their occurrence.  相似文献   
964.
Human glioblastoma cells secrete a peptide termed glioblastoma-derived T cell suppressor factor (G-TsF) which inhibits T cell activation. Recently, purification and cloning of G-TsF revealed that G-TsF is identical to transforming growth factor-beta 2. As shown here, G-TsF suppresses the growth of an ovalbumin-specific mouse T helper cell clone (OVA-7T) independently of the stimulus used being either (a) antigen in the presence of antigen-presenting cells, or (b) interleukin 2 (IL2) or (c) phorbol ester and calcium ionophore. Furthermore, in the presence of antibodies against IL2 receptors, G-TsF was able to suppress the residual proliferation still observed when OVA-7T were stimulated with phorbol ester/ionophore. G-TsF failed to inhibit the release of IL3 from OVA-7T activated with IL2. Taken together, the data provide evidence that G-TsF does not directly interfere with interactions of IL2 with its receptor but rather inhibits T cell activation by interfering with an as yet unidentified pathway used by both IL2 and phorbol ester/ionophore. When analyzing different monokines and lymphokines for its effect on G-TsF-induced suppression of T cell growth the only factor found to partially neutralize the effect of G-TsF was tumor necrosis factor-alpha.  相似文献   
965.
Recent results obtained using molecular biology techniques have suggested a possible role for insulin-like growth factor II (IGF-II) in the pathogenesis of hepatocellular carcinoma (HCC). To investigate this phenomenon, a monoclonal anti-body was used against IGF-II to study 54 patients with HCC. The presence of HBsAg was also tested both in serum and liver tissue. A positive immunoreaction was found in 9/15 (60%) of the HCC arising in cirrhotic livers of patients who had serum markers for HBV (HBV+ positive patients). These results provide further evidence that HBV might play a role in the expression of IGF-II. In HCC of patients without any markers of HBV infection (HBV- negative patients), IGF–II was detected in 10/39 (25.6%) of the tumors, and in some benign neoplastic lesions. It was found not only in neoplastic cells but also in some dysplastic nodules. The speculation arises that IGF–II expression may play a role in some steps of hepato-carcinogenesis.  相似文献   
966.
The differentiated clone 19A of the HT-29 human colon carcinoma cell line was used as a model to study the intracellular electrophysiological effects of interaction of the cAMP, the protein kinase C (PKC) and the Ca2+ pathways, (a) A synergistic effect between ionomycin and forskolin was observed. From intracellular responses it was concluded that the synergistic effect is caused by activation of an apical Cl conductance by protein kinase A and a basolateral K+ conductance by Ca2+. (b) A transient synergistic effect of ionomycin and the phorbol ester phorbol dibutyrate (PDB) was found. The decrease of the response appeared to be due to PKC-dependent inactivation of the basolateral K+ conductance. The synergism is caused by PKC-dependent increase of the apical Cl conductance and Ca2+-dependent increase of the basolateral K+ conductance. (c) The effects of carbachol and PDB were not fully additive presumably because of their convergence on PKC activation, (d) Forskolin and PDB, when added in this order, had a less than additive effect. Results of cell-attached patch-clamp studies, presented in the accompanying paper, showed a synergistic effect of forskolin and PDB on non-rectifying small-conductance Cl channels. Assuming that these channels are involved in the transepithelial responses it is suggested that forskolin and PDB induce a modulatory, synergistic increase of the apical Cl conductance when both pathways are activated simultaneously. (e) The HT-29cl.19A cells differ from T84 cells in that the latter did not respond with an increase of the short-circuit current to addition of phorbol ester. This may be due to a very low expression of PKC.  相似文献   
967.
The authors examined urine specimens from 30 patients with multiple myeloma (MM) to determine the usefulness of cytodiagnostic urinalysis in evaluating such patients. Nine patients had clinical evidence of renal failure. In six of these nine patients (67%), or 20% of all patients, the urine sediment contained unique "MM-casts." These were characterized by a waxy to granular matrix surrounded by reactive, syncytial, giant cells with occasional renal cells embedded in the cast matrix. These casts were not observed in urine specimens from patients with normal renal function. Renal biopsy in two patients with MM-casts confirmed that cytologic diagnosis of "MM-kidney." The patient groups with or without MM-casts were comparable with respect to age, sex, and clinical stage of disease. In contrast, those with MM-casts were more likely to have clinical evidence of renal disease (100% vs. 13%), Bence Jones proteinuria (100% vs. 35%), hypercalcemia (50% vs. 8%), and hyperuricemia (50% vs. 4%). The two groups could not be distinguished reliably by urine physicochemical determinations. However, there were marked differences in the frequency of microscopic abnormalities. All patients with MM-cast formation excreted other pathologic casts as well and had evidence of tubular injury, while five of six had evidence of ischemic necrosis. This compared with 17%, 13%, and 21%, respectively, of those without MM-casts. Thus, cytodiagnostic urinalysis is of value in distinguishing MM-kidney from the numerous other causes of renal failure in patients with MM.  相似文献   
968.
True hermaphroditism with XX/XY sex chromosome mosaicism: Report of a case   总被引:1,自引:0,他引:1  
A case of true hermaphroditism with 46, XX/46, XY karyotype is reported. The propositus, reared as a male, showed ambiguous external genitalia with perineoscrotal hypospadias, and internal genitalia represented by bilateral ovotestes, normal uterus and tubes. Periodic menstrual bleedings appeared at puberty. The endocrinologic data demonstrated the secretory activity of both the ovarian and the testicular tissue. The analysis of red cell, lymphocyte and serum markers, done on the propositus and on his parents, failed to show any evidence of double fertilization. On this basis, the origin of the XX/XY condition (mosaicism versus chimerism) and its developmental consequences are discussed.  相似文献   
969.
The changes in viral load and CD4(+) count at 3 and 6 months in a group of 166 HIV-infected patients was evaluated. The new therapy was chosen based on the medical history procedures for 70 patients, and in 96 patients it was guided by the partial or complete result of the line probe assay (LiPA) HIV RT and Protease resistance tests. The absolute difference from the baseline of the log viral load at 3 and 6 months was significantly different between the two groups when adjusted for baseline viral load (P < 0.0001) and stayed significant when intention-to-treat analysis was carried out (P < 0.001). The absolute difference of the CD4(+) count was not significantly different when adjusted for baseline CD4(+) (P = 0.854, 3 months; P = 0.06, 6 months). The proportion of patients with a viral load 相似文献   
970.
We have isolated the complete coding region of HLA‐B*39 from a Spanish Caucasoid, using a new PCR primer for its 5′ untranslated region. The cDNA matched partial genomic sequences of B*3924, an allele whose distribution appears to be restricted to Mediterranean and Arabian Caucasoids. A single amino acid change exclusive to B*3924 (threonine‐98) distinguishes it from B*3903.  相似文献   
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