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101.
Anna Scattone Gilda Caruso Andrea Marzullo Domenico Piscitelli Mattia Gentile Lucia Bonadonna Giuseppe Balducci Maria Cristina Digilio Alessandro Jenkner Francesca Diomedi Camassei Renata Boldrini Pietro Nazzaro Lucio Pollice Gabriella Serio 《Fetal and pediatric pathology》2003,22(4):323-341
Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. Comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours. 相似文献
102.
M. Cruz J.M. Tusell D. Grillo‐Bosch F. Albericio J. Serratosa F. Rabanal E. Giralt 《Chemical biology & drug design》2004,63(3):324-328
Abstract: Single N‐methyl amino acid‐containing peptides related to the central hydrophobic region β16–20 (Lys‐Leu‐Val‐Phe‐Phe) of the β‐amyloid protein are able to reduce the cytotoxicity of natural β1–42 in PC12 cell cultures. N‐methyl phenylalanine analogs yield statistically significant increments in cell viability (Student's t‐test < 0.01%) and are nontoxic in the same assay. These promising results indicate that these peptide molecules could be a starting point for the development of potential therapeutic compounds for the treatment of Alzheimer's disease. 相似文献
103.
The pathology of late recurrence of testicular germ cell tumors 总被引:16,自引:0,他引:16
Michael H Lucia J Foster RS Ulbright TM 《The American journal of surgical pathology》2000,24(2):257-273
A total of 91 men had histologically documented late recurrences of testicular germ cell tumors characterized by a complete response to treatment with a subsequent disease-free interval of at least 2 years and no evidence of a second primary lesion. Ninety percent of the patients for whom information was available received chemotherapy shortly after their initial diagnosis of testicular germ cell tumors; most of the other patients were known to have stage I disease initially. Overall, 60% of patients had teratoma in their late recurrences, including 20 patients (22%) in whom teratoma was the only element. Thus, teratoma was the most common type of neoplasm in late recurrences. Excluding teratoma coexisting with other types of neoplasms, yolk sac tumor was the most frequent type of tumor in patients with late recurrence. It occurred in 47% of patients, either alone or with teratoma, another nonteratomatous germ cell tumor type, or a "nongerm cell malignant tumor." Unusual types of yolk sac tumor, including glandular, parietal, clear cell, and pleomorphic patterns, were seen frequently in late recurrences and often raised differential diagnostic problems with "nongerm cell" carcinomas. A smaller number of late recurrences consisted of other types of neoplasms. Twenty percent of patients with late recurrence had a nonteratomatous germ cell tumor other than yolk sac tumor, either alone, with yolk sac tumor, or with a "nongerm cell malignant tumor." Most of these nonteratomatous germ cell tumors other than yolk sac tumor were embryonal carcinoma, although rarely seminoma and choriocarcinoma were encountered. "Nongerm cell malignant tumors," including both sarcomas and carcinomas of various types, occurred in 23% of late-recurrence patients, either alone or with a nonteratomatous germ cell tumor. Late recurrences were seen in many different sites in these patients, including the retroperitoneum, abdomen, pelvis, liver, mediastinum, lung, bone (femur, vertebra, and rib), lymph nodes outside the retroperitoneum and mediastinum (supraclavicular, neck, and axillary regions), scrotum and inguinal regions, adrenal gland, chest wall, and buttocks. Follow-up data were available for 79 of the 91 patients studied. Duration of follow-up ranged from 2 months to 13 years after the patient's first late recurrences; the mean length of follow-up was 4.8 years. Patients whose late recurrences consisted of teratoma only had the most favorable outcomes, with 79% having no evidence of disease at last follow-up. Patients whose late recurrences consisted of pure "nongerm cell malignant tumor" or pure germ cell tumor (yolk sac tumor or other types) had a much worse prognosis: Only 36% to 37% were alive with no evidence of disease. Patients with two different types of nonteratomatous malignancies in their late recurrences had a dismal clinical course: Only 17% with both yolk sac tumor and other nonteratomatous germ cell tumor had no evidence of disease, whereas no patient with both nonteratomatous germ cell tumor and "nongerm cell malignant tumor" was disease free. Late recurrences consisting of teratoma alone often have a favorable outcome, but the prognosis in all other patients is poor. Furthermore, late recurrence is not likely to respond to chemotherapy and is best treated by surgical excision when possible. 相似文献
104.
Carlo Gambacorti-Passerini Massimo Zucchetti Domenico Russo Roberta Frapolli Magda Verga Silvia Bungaro Lucia Tornaghi Fabio Rossi Pietro Pioltelli Enrico Pogliani Daniele Alberti Gianmarco Corneo Maurizio D'Incalci 《Clinical cancer research》2003,9(2):625-632
PURPOSE: Imatinib (Glivec) is a potent inhibitor of bcr/abl, an oncogenic fusion protein that causes chronic myelogenous leukemia (CML). alpha1 acid glycoprotein (AGP) binds to imatinib with high affinity and inhibits imatinib activity in vitro and in vivo in an animal model. A pharmacokinetics analysis of imatinib was undertaken in CML patients. EXPERIMENTAL DESIGN: Imatinib plasma concentrations were measured in 19 CML patients treated with imatinib (400 or 600 mg/day). Five patients received a concomitant short-term course of clindamycin (CLI). RESULTS: A positive correlation between AGP and imatinib plasma levels was observed. CLI administration decreased imatinib plasma concentrations, evaluated as area under the curve (AUC) and peak concentrations (C(max)). The effects of a bolus of CLI was studied in three patients on imatinib 23 h after the last imatinib dose. Within 5-10 min in three of three cases, CLI caused a decrease in imatinib plasma concentrations of 2.6-, 2.7-, and 4.7-fold, respectively. In vitro experiments using fresh blasts from CML patients showed that AGP, at concentrations observed in the patients, decreased imatinib intracellular concentrations up to 10 times and blocked imatinib activity. The incubation with CLI restored imatinib intracellular concentrations and biological activity. CONCLUSION: AGP exerts significant effects of the pharmacokinetics, plasma concentrations, and intracellular distribution of imatinib in CML patients; these data indicate that plasma imatinib levels represent unreliable indicators of the cellular concentrations of this molecule. 相似文献
105.
Salvatore Caruso Agostino Serra Luigi Maiolino Carmela Agnello Lucia Di Mari Sara Ruta Angelo Arcidiacono Antonio Cianci 《The European journal of contraception & reproductive health care》2006,11(4):250-257
OBJECTIVE: To determine the effects of monophasic oral contraceptives on the nasal respiratory epithelium in premenopausal women. DESIGN: Prospective open clinical trial. SETTING: Outpatient Family Planning Centre. PATIENT(S): Eighty-eight premenopausal women, with ovulatory cycle, who were planning to take oral contraceptives. INTERVENTION(S): Baseline endovaginal ultrasound examination and blood test to measure serum progesterone to confirm ovulatory cycle. Thirty-eight women on pill containing 30 microg ethinylestradiol (EE) plus 75 microg gestodene, and 35 women on pill containing 15 microg ethinylestradiol plus 60 microg gestodene. MAIN OUTCOMES/MEASURE(S): Cytological changes on the nasal respiratory epithelium evaluated with the maturation index performed during the follicular, periovular, and luteal phases of the menstrual cycle, and on the sixth cycle of pill intake. RESULT(S): Hematoxylin-eosin staining for the maturation index showed similar trophic cytological aspects between the nasal and vaginal epithelium during the menstrual cycle and pill usage. Both the nasal and vaginal cytological samples showed higher maturation indexes during both the follicular and the periovular phases than during the luteal phase. Women on pill containing 15 microg EE showed lower trophic aspects in the nasal cytological samples compared with those on pill with 30 microg EE. CONCLUSION(S): Along with the vaginal cells, the nasal respiratory epithelium is an ovarian steroid target. The maturation index of the nasal respiratory epithelium seems to depend on the variation of the ovarian steroids during the menstrual cycle and on the iatrogenic effects of oral contraceptives. 相似文献
106.
B7-h4 is highly expressed in ductal and lobular breast cancer. 总被引:9,自引:0,他引:9
Barbara Tringler Shaoqiu Zhuo Glenn Pilkington Kathleen C Torkko Meenakshi Singh M Scott Lucia David E Heinz Jackie Papkoff Kenneth R Shroyer 《Clinical cancer research》2005,11(5):1842-1848
PURPOSE: This study was designed to investigate the expression of B7-H4 protein, a member of the B7 family that is involved in the regulation of antigen-specific immune responses, in normal breast and in primary and metastatic breast carcinomas. EXPERIMENTAL DESIGN: Archival formalin-fixed tissue blocks from breast cancers and normal somatic tissues were evaluated for B7-H4 expression by immunohistochemistry with manual and automated image analysis. The proportion of B7-H4-positive cells and the intensity of B7-H4 staining were compared with histologic type, grade, stage, hormone receptor status, and HER-2/neu status. RESULTS: B7-H4 was detected in 165 of 173 (95.4%) primary breast cancers and in 240 of 246 (97.6%) metastatic breast cancers. B7-H4 staining intensity was greater in invasive ductal carcinomas [24.61 relative units (RU)] and in invasive lobular carcinomas (15.23 RU) than in normal breast epithelium (4.30 RU, P = 0.0003). Increased staining intensity was associated with negative progesterone receptor status (P = 0.014) and history of neoadjuvant chemotherapy (P = 0.004), and the proportion of B7-H4-positive cells was associated with negative progesterone receptor (P = 0.001) and negative HER-2/neu (P = 0.024) status. However, there was no statistically significant relationship between the proportion of B7-H4-positive cells or staining intensity and grade, stage, or other clinicopathologic variables. Low levels of B7-H4 expression were also detected in epithelial cells of the female genital tract, lung, pancreas, and kidney, but B7-H4 was generally absent in most other normal somatic tissues. CONCLUSIONS: The nearly ubiquitous expression of B7-H4 in breast cancer, independent of tumor grade or stage, suggests a critical role for this protein in breast cancer biology. 相似文献
107.
Alessio Nencioni Lucia Wille Giovanna Dal Bello Davide Boy Gabriella Cirmena Sebastian Wesselborg Claus Belka Peter Brossart Franco Patrone Alberto Ballestrero 《Clinical cancer research》2005,11(11):4259-4265
PURPOSE: Bcl-2 overexpression is frequently detected in lymphoid malignancies, being associated with poor prognosis and reduced response to therapy. Here, we evaluated whether Bcl-2 overexpression affects the cytotoxic activity of proteasome inhibitors taken alone or in association with conventional anticancer drugs or tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). EXPERIMENTAL DESIGN: Jurkat cells engineered to overexpress Bcl-2 were treated with proteasome inhibitors (MG132, epoxomicin, and bortezomib), anticancer drugs (etoposide and doxorubicin), TRAIL, or combinations of these compounds. Cell death and loss of mitochondrial transmembrane potential were detected by flow cytometry. Cytosolic relocalization of cytochrome c and SMAC/Diablo, caspase cleavage, and Bcl-2 and Mcl-1 levels were determined by immunoblotting. Nuclear factor-kappaB inhibition was done by retroviral transduction with a dominant-negative mutant of IkappaBalpha. RESULTS: Bcl-2 overexpression results in significant inhibition of apoptosis in response to proteasome inhibitors, antiblastics, and TRAIL. Addition of TRAIL to proteasome inhibitors results in a synergistic cytotoxic effect in Bcl-2-overexpressing cells, whereas this result is not reproduced by the combination of proteasome inhibitors with antiblastic drugs. Importantly, proteasome inhibitors plus TRAIL induce mitochondrial dysfunction irrespective of up-regulated Bcl-2. Bcl-2 cleavage to a fragment with putative proapoptotic activity and elimination of antiapoptotic Mcl-1 may both play a role in proteasome inhibitors-TRAIL cooperation. Conversely, nuclear factor-kappaB inhibition by proteasome inhibitors is per se insufficient to explain the observed synergy. CONCLUSIONS: Combined proteasome inhibitors and TRAIL overcome the apoptotic threshold raised by Bcl-2 and may prove useful in the treatment of chemoresistant malignancies with up-regulated Bcl-2. 相似文献
108.
Association of CYP2C8, CYP3A4, CYP3A5, and ABCB1 polymorphisms with the pharmacokinetics of paclitaxel. 总被引:4,自引:0,他引:4
Anja Henningsson Sharon Marsh Walter J Loos Mats O Karlsson Adam Garsa Klaus Mross Stephan Mielke Lucia Viganò Alberta Locatelli Jaap Verweij Alex Sparreboom Howard L McLeod 《Clinical cancer research》2005,11(22):8097-8104
PURPOSE: To retrospectively evaluate the effects of six known allelic variants in the CYP2C8, CYP3A4, CYP3A5, and ABCB1 genes on the pharmacokinetics of the anticancer agent paclitaxel (Taxol). EXPERIMENTAL DESIGN: A cohort of 97 Caucasian patients with cancer (median age, 57 years) received paclitaxel as an i.v. infusion (dose range, 80-225 mg/m(2)). Genomic DNA was analyzed using PCR RFLP or using Pyrosequencing. Pharmacokinetic variables for unbound paclitaxel were estimated using nonlinear mixed effect modeling. The effects of genotypes on typical value of clearance were evaluated with the likelihood ratio test within NONMEM. In addition, relations between genotype and individual pharmacokinetic variable estimates were evaluated with one-way ANOVA. RESULTS: The allele frequencies for the CYP2C8*2, CYP2C8*3, CYP2C8*4, CYP3A4*3, CYP3A5*3C, and ABCB1 3435C>T variants were 0.7%, 9.2%, 2.1%, 0.5%, 93.2%, and 47.1%, respectively, and all were in Hardy-Weinberg equilibrium. The population typical value of clearance of unbound paclitaxel was 301 L/h (individual clearance range, 83.7-1055 L/h). The CYP2C8 or CYP3A4/5 genotypes were not statistically significantly associated with unbound clearance of paclitaxel. Likewise, no statistically significant association was observed between the ABCB1 3435C>T variant and any of the studied pharmacokinetic variables. CONCLUSIONS: This study indicates that the presently evaluated variant alleles in the CYP2C8, CYP3A4, CYP3A5, and ABCB1 genes do not explain the substantial interindividual variability in paclitaxel pharmacokinetics. 相似文献
109.
110.
Ana-Maria Prelipcean Andreea Iosageanu Alexandra Gaspar-Pintiliescu Lucia Moldovan Oana Craciunescu Ticuta Negreanu-Pirjol Bogdan Negreanu-Pirjol Raul-Augustin Mitran Mariana Marin Ugo DAmora 《Materials》2022,15(10)
Over the past years, research attention has been focusing more on waste-derived, naturally derived, and renewable materials, in the view of a more sustainable economy. In this work, different topical formulations were obtained from the valorization of marine and agro-industrial by-products and the use of Carbopol 940 as gelling agent. In particular, the combination of extracts obtained from the marine snail, Rapanosa venosa, with Cladophora vagabunda and grape pomace extracts, was investigated for wound healing purposes. Rapana venosa has demonstrated wound healing properties and antioxidant activity. Similarly, grape pomace extracts have been shown to accelerate the healing process. However, their synergic use has not been explored yet. To this aim, four different formulations were produced. Three formulations differed for the presence of a different extract of Rapana venosa: marine collagen, marine gelatin, and collagen hydrolysate, while another formulation used mammalian gelatin as further control. Physico-chemical properties of the extracts as well as of the formulations were analyzed. Furthermore, thermal stability was evaluated by thermogravimetric analysis. Antioxidant capacity and biological behavior, in terms of cytocompatibility, wound healing, and antimicrobial potential, were assessed. The results highlighted for all the formulations (i) a good conservation and thermal stability in time, (ii) a neutralizing activity against free radicals, (iii) and high degree of cytocompatibility and tissue regeneration potential. In particular, collagen, gelatin, and collagen hydrolysate obtained from the Rapana venosa marine snail represent an important, valuable alternative to mammalian products. 相似文献