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91.
Inhibitory effect of bikunin on calcium oxalate crystallization in vitro and urinary bikunin decrease in renal stone formers 总被引:5,自引:0,他引:5
Médétognon-Benissan J Tardivel S Hennequin C Daudon M Drüeke T Lacour B 《Urological research》1999,27(1):69-75
Two proteins of 17 and 24 kDa, respectively, which were immunologically related to bikunin, were purified from urine of healthy
men, using in the last step a trypsin CNBr-sepharose affinity column. These proteins strongly inhibited calcium oxalate (CaOx)
crystallization in two in vitro models. In the first model, the presence of 8 μg/ml protein in a medium containing 0.76 mM
CaCl2 (with 45Ca) and 0.76 mM ammonium oxalate inhibited the crystallization process by 80%, as estimated by supernatant radioactivity after
60 min of incubation. A similar inhibition was observed in the second turbidimetric model, where the CaOx crystallization
kinetics were followed for 10 min at 620 nm in a medium containing 4 mM CaCl2 and 0.5 mM Na2Ox. These proteins were used as standard protein for the development of an enzyme-linked immunosorbent assay (ELISA) in urine.
Mean (± SEM) urinary bikunin concentration in 18 healthy subjects was 5.01 ± 0.91 μg/ml. This was a concentration range of
strong inhibitory activity in vitro. Bikunin values were nearly 50% lower (2.54 ± 0.42 μg/ml, P=0.007) in 31 CaOx renal stone formers (having weddelite crystals in their first morning urine) than in the healthy volunteers.
A correlation was found between urinary bikunin and alpha-1 microglobulin concentrations in the control group (y=0.73x + 1.09, r
2=0.8) while no such correlation existed in the lithiasis group. In conclusion, bikunin exerts a strong inhibitory action of
CaOx crystallization in vitro. Its involvement in urinary CaOx crystallization of stone formers is highly probable, based
on the significant decrease in its urinary concentration in the majority of stone formers studied.
Received: 16 December 1997 / Accepted: 23 June 1998 相似文献
92.
The Prader-Willi syndrome shortens the life of patients due to the morbid obesity which it entails. The compulsive hyperphagia
associated with it makes a dietetic treatment or a gastroplasty difficult. This study presents the case-histories of three
patients suffering from the Prader-Willi syndrome who were operated on by means of a Scopinaro's bilio-pancreatic diversion.
Following a marked reduction the first year, the weight loss stabilized and then tended to diminish. The observation of three
cases which continued for two and a half to six years did not reveal any considerable metabolic problems. The deficiency of
iron, vitamins D and B12 as well as folic acid had to be made up by supplementation. These results are comparable with the
most favorable ones in the literature. Even if the effect on the weight loss is not spectacular, the operation manages to
hold off the development of the obesity, inexorable for those with the Prader-Willi syndrome, and prevents lethal complications,
without having notable side effects. Lifting coercive dietary measures improves the quality of life. 相似文献
93.
Marzena Karcz-Kubicha Katerina Antoniou Anton Terasmaa Davide Quarta Marcello Solinas Zuzana Justinova Antonella Pezzola Rosaria Reggio Christa E Müller Kjell Fuxe Steven R Goldberg Patrizia Popoli Sergi Ferré 《Neuropsychopharmacology》2003,28(7):1281-1291
The involvement of adenosine A(1) and A(2A) receptors in the motor effects of caffeine is still a matter of debate. In the present study, counteraction of the motor-depressant effects of the selective A(1) receptor agonist CPA and the A(2A) receptor agonist CGS 21680 by caffeine, the selective A(1) receptor antagonist CPT, and the A(2A) receptor antagonist MSX-3 was compared. CPT and MSX-3 produced motor activation at the same doses that selectively counteracted motor depression induced by CPA and CGS 21680, respectively. Caffeine also counteracted motor depression induced by CPA and CGS 21680 at doses that produced motor activation. However, caffeine was less effective than CPT at counteracting CPA and even less effective than MSX-3 at counteracting CGS 21680. On the other hand, when administered alone in habituated animals, caffeine produced stronger motor activation than CPT or MSX-3. An additive effect on motor activation was obtained when CPT and MSX-3 were coadministered. Altogether, these results suggest that the motor-activating effects of acutely administered caffeine in rats involve the central blockade of both A(1) and A(2A) receptors. Chronic exposure to caffeine in the drinking water (1.0 mg/ml) resulted in tolerance to the motor effects of an acute administration of caffeine, lack of tolerance to amphetamine, apparent tolerance to MSX-3 (shift to the left of its 'bell-shaped' dose-response curve), and true cross-tolerance to CPT. The present results suggest that development of tolerance to the effects of A(1) receptor blockade might be mostly responsible for the tolerance to the motor-activating effects of caffeine and that the residual motor-activating effects of caffeine in tolerant individuals might be mostly because of A(2A) receptor blockade. 相似文献
94.
Soluble CD40 ligand plasma levels in lung cancer. 总被引:7,自引:0,他引:7
Mario Roselli Tommaso C Mineo Stefania Basili Francesca Martini Sabrina Mariotti Simona Aloe Girolamo Del Monte Vincenzo Ambrogi Antonella Spila Raffaele Palmirotta Roberta D'Alessandro Giovanni Davì Fiorella Guadagni Patrizia Ferroni 《Clinical cancer research》2004,10(2):610-614
PURPOSE: Tumor-induced platelet activation may cause the release of various cytokines, including CD40 ligand (CD40L). Activation of the CD40/CD40L pathway in human tumors may result in thrombin generation, which is known to be involved in angiogenesis. Thus, we investigated whether soluble (s)CD40L levels are increased in patients with lung cancer as a result of platelet and/or coagulation activation. EXPERIMENTAL DESIGN: Citrated plasma samples were obtained from 120 patients with different stages and histotypes of lung cancer and 60 age- and sex-matched control subjects. sCD40L, sP-selectin (marker of platelet activation), prothrombin fragment 1 + 2, and thrombin-antithrombin III complex levels (both markers of coagulative activation) were measured in all samples. RESULTS: Patients with lung cancer had median sCD40L levels higher than in control subjects (0.46 versus 0.13 ng/ml; P < 0.0001), although correlation with the stage of disease was not evident. Nonetheless, sCD40L levels were significantly higher in squamous cancer compared with adenocarcinoma (0.75 versus 0.27 ng/ml; P < 0.05). Moreover, median sCD40L levels were higher in stage IV compared with nonmetastatic squamous lung cancer (1.02 versus 0.61 ng/ml; P < 0.05). sCD40L levels significantly correlated with sP-selectin (P < 0.001), prothrombin fragment 1 + 2 (P < 0.001), or thrombin-antithrombin III complex (P < 0.05) in squamous lung cancer, but only sP-selectin (P = 0.011) was independently related to sCD40L. CONCLUSIONS: These findings indicate that elevated sCD40L levels can be preferentially found in patients with advanced squamous cancer and provide evidence that increased levels of this cytokine are associated to the occurrence of in vivo platelet activation. 相似文献
95.
Véronique Diéras Pierre Fumoleau Gilles Romieu Michèle Tubiana-Hulin Mo?se Namer Louis Mauriac Jean-Paul Guastalla Eric Pujade-Lauraine Pierre Kerbrat Philippe Maillart Frédérique Pénault-Llorca Marc Buyse Pierre Pouillart 《Journal of clinical oncology》2004,22(24):4958-4965
PURPOSE: This randomized, noncomparative, parallel-group study was designed to evaluate the pathologic complete response (pCR) rate of combined doxorubicin plus paclitaxel (AP) and doxorubicin plus cyclophosphamide (AC) as neoadjuvant chemotherapy in patients with previously untreated breast cancer who were unsuitable for conservative surgery. PATIENTS AND METHODS: A total of 200 patients with T2-3, N0-1, M0 disease were randomly assigned in a 2:1 ratio to receive preoperative chemotherapy with either doxorubicin 60 mg/m(2) plus paclitaxel 200 mg/m(2) as a 3-hour infusion (AP) or doxorubicin 60 mg/m(2) plus cyclophosphamide 600 mg/m(2) (AC) every 3 weeks for 4 courses followed by surgery. RESULTS: A pCR (eradication of invasive carcinoma in tumor and in axillary lymph nodes) was found in 16% and 10% of patients in the AP and AC arms, respectively, by study center pathologists, and in 8% and 6% of patients, respectively, by independent pathologists. Patients with pCRs tended to have unifocal disease, tumors with negative hormonal receptor status, and less differentiation (Scarff, Bloom, and Richardson scale grade 3). Breast-conserving surgery was performed in 58% and 45% of patients in the AP and AC arms, respectively. An objective clinical response was achieved in 89% of patients in the AP arm and 70% in the AC arm. At a median follow-up of 31 months, disease-free survival (DFS) was higher in patients who reached pCR versus those without pCR (91% v 70%). CONCLUSION: The encouraging pathologic and clinical responses of patients with breast cancer after neoadjuvant chemotherapy with doxorubicin plus paclitaxel warrant additional investigation of paclitaxel in the neoadjuvant setting of breast cancer management. 相似文献
96.
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
97.
C-Jun NH(2)-terminal kinase mediates proliferation and tumor growth of human prostate carcinoma. 总被引:1,自引:0,他引:1
Yong-Min Yang Frédéric Bost Wilfried Charbono Nicholas Dean Robert McKay Johng S Rhim Chantal Depatie Dan Mercola 《Clinical cancer research》2003,9(1):391-401
PURPOSE: C-Jun NH(2)-terminal kinase (JNK) has been implicated in numerous functions including stress responses, apoptosis,and transformation. The role in transformation is based largely on studies of isolated cell types with little indication of whether JNK plays a general role in a specific human tumor type or whether this occurs in vivo. EXPERIMENTAL DESIGN: We examined 9 human prostate carcinoma cell lines in vitro and a representative line in vivo. RESULTS: For all of the cell lines proliferation is highly correlated with serum-supported JNK activity (r(Pearson) = 0.91; P = 0.004), whereas no relationship was observed for 10 human breast cancer cell lines (r(Pearson) = -0.32). Treatment with characterized antisense oligonucleotides complementary to sequences common to either the JNK1 or JNK2 family of isoforms showed that, whereas antisense JNK1 inhibited growth by a maximum of 57%, antisense JNK2 inhibited proliferation up to 80%. Sense and scrambled control oligonucleotides had little effect (average 3.7 +/- 1.5%). Moreover, systemic treatment of mice bearing established xenografts of PC3 prostate carcinoma cells with antisense JNK1 and JNK2 led to inhibition tumor growth by 57% (P < 0.002) and 80% (P < 0.001), respectively. The difference is significant (P < 0.012). Combined antisense treatment led to a significant increase in frequency of tumor regression (P = 0.022). CONCLUSION: These results indicate that JNK is required for growth of prostate carcinoma cells in vitro and in vivo, and additionally indicate that JNK2 plays a dominant role. The JNK pathway is a novel target in the treatment of prostate carcinoma. 相似文献
98.
99.
100.
Summary A rare case of a spinal papillary meningioma in a 19-year-old adolescent is described. Six months after radical resection
the patient showed dissemination along the cerebrospinal pathway. Papillary meningiomas are rare tumours with a relatively
high incidence in childhood. Most papillary meningiomas reported in the literature are considered as aggressive variants of
meningioma with often local recurrence, dissemination in the CSF and metastases to remote sites. This case supports that,
although the histogenesis remains unexplained, papillary meningiomas deserve recognition on the basis of their high morbidity
and mortality. 相似文献