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71.
Vascular endothelial growth factor and p53 expressions in liver and abdominal metastases from colon cancer. 总被引:4,自引:0,他引:4
Stefano Cascinu Francesco Graziano Vincenzo Catalano Sandro Barni Paolo Giordani Anna Maria Baldelli Maria Pia Staccioli Cristina Rossi Angelo Brenna Andrea Valenti Pietro Muretto Giuseppina Catalano 《Tumour biology》2003,24(2):77-81
OBJECTIVE: To determine the relationship between p53 overexpression and vascular endothelial growth factor (VEGF) upregulation in liver and abdominal metastases from colon cancer. The analysis in the two metastatic sites was carried out to evaluate the potential role of microenvironment in the molecular regulation of VEGF. METHODS: Bioptic specimens of liver and abdominal metastases from colon carcinomas were examined by immunohistochemistry for p53 and VEGF expressions. Consecutive cases with assessable tumor tissue were selected. RESULTS: The study population consisted of 24 cases having liver metastases and 34 cases having abdominal metastases. Abdominal metastases showed a higher number of VEGF-positive cases and a higher intensity of VEGF immunoreactivity than liver metastases did (p = 0.01). The combined analysis of p53 and VEGF showed a strong association between the two markers in the 24 liver metastases; 9 cases were VEGF positive/p53 positive and 15 cases were VEGF negative/p53 negative. This relationship was not found in the 34 abdominal metastases, which showed concordance between the two markers in 9 VEGF-positive/p53-positive cases only. CONCLUSIONS: Microenvironment factors like hypoxia may have a predominant role in inducing VEGF expression and they can override the molecular control of p53 on VEGF. 相似文献
72.
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
73.
Congenital abnormalities of the umbilical venous system are rare. A case of fatal right congenital diaphragmatic hernia (CDH)
in association with an anomalous umbilical vein bypassing the liver and directly entering the right atrium is presented. The
ductus venosus was absent. Although much of the liver was within the right hemithorax, radiographs showed an apparently normal
umbilical venous catheter (UVC) course, suggesting a normally positioned liver and mitigating against the diagnosis of CDH.
Aberrant umbilical drainage, yielding a falsely normal appearing UVC course, may delay the diagnosis of CDH.
Received: 26 July 1996 Accepted: 6 November 1996 相似文献
74.
Kathrin Mühlemann Christine Franzini Christoph Aebi Christoph Berger David Nadal Jody St?helin Hanspeter Gnehm Klara Posfay-Barbe Alain Gervaix Hugo Sax Ulrich Heininger Jan Bonhoeffer Gerhard Eich Christian Kind Christiane Petignat Pietro Scalfaro 《Infection control and hospital epidemiology》2004,25(9):765-771
OBJECTIVE: To acquire data on pediatric nosocomial infections (NIs), which are associated with substantial morbidity and mortality and for which data are scarce. DESIGN: Prevalence survey and evaluation of a new comorbidity index. SETTING: Seven Swiss pediatric hospitals. PATIENTS: Those hospitalized for at least 24 hours in a medical, surgical, intensive care, or intermediate care ward. RESULTS: Thirty-five NIs were observed among 520 patients (6.7%; range per hospital, 1.4% to 11.8%). Bacteremia was most frequent (2.5 per 100 patients), followed by urinary tract infection (1.3 per 100 patients) and surgical-site infection (1.1 per 100 patients; 3.2 per 100 patients undergoing surgery). The median duration until the onset of infection was 19 days. Independent risk factors for NI were age between 1 and 12 months, a comorbidity score of 2 or greater, and a urinary catheter. Among surgical patients, an American Society of Anesthesiologists (ASA) score of 2 or greater was associated with any type of NI (P = .03). Enterobacteriaceae were the most frequent cause of NI, followed by coagulase-negative staphylococci; viruses were rarely the cause. CONCLUSIONS: This national prevalence survey yielded valuable information about the rate and risk factors of pediatric NI. A new comorbidity score showed promising performance. ASA score may be a predictor of NI. The season in which a prevalence survey is conducted must be considered, as this determines whether seasonal viral infections are observed. Periodic prevalence surveys are a simple and cost-effective method for assessing NI and comparing rates among pediatric hospitals. 相似文献
75.
Effects of hyaluronan on free-radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in rabbits. 总被引:1,自引:0,他引:1
Giovanni Camillieri Annarita Nastasi Pietro Gulino Claudio Bucolo Filippo Drago 《Journal of ocular pharmacology and therapeutics》2004,20(2):151-157
Free-radical formation may play a role in postoperative complications of phacoemulsification (e.g., corneal endothelium damage from mechanical injury). The present experiments were aimed at investigating whether different molecular weight ranges (2000-2600, 2600-3200, or 3200-3800 kDa) of hyaluronan may influence free radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in the rabbit eye. The viscoelastic substance was injected in the anterior chamber of rabbits' eyes before phacoemulsification, at a 2.5% concentration. The formation of free radicals was determined by adding luminol to the irrigation media and measuring the chemoluminescence in eyes. The corneal endothelial damage was evaluated by measuring the corneal central thickness by pachimetry. The inflammation parameters were measured by calculation in aqueous humor of peak levels of leukocytes and prostaglandin E(2) (PGE(2)) and evaluation in uveal tissue of myeloperoxidase activity. Hyaluronan decreased by about 58-60% free-radical formation during phacoemulsification, reduced by about 76-80% modifications in mean corneal thickness and by about 54-61% the corneal endothelial cell loss in all molecular weight ranges used. No difference was found among various molecular weight ranges. The highest molecular weight range showed to be more potent than the lowest range for reduced number of inflammation cells and level of PGE(2) in aqueous humor. Thus, hyaluronan reduces free-radical formation, exerts protection on the corneal endothelium and exerts anti-inflammation properties after phacoemulsification in rabbits. The latter effect seems to depend on the molecular weight of the substance. 相似文献
76.
Barbuscia M Dattola P Di Pietro N Gorgone S Rizzo AG Romeo C Crocco P Trimarchi L 《Annali italiani di chirurgia》2000,71(1):89-93; discussion 94
The authors relate their statistic about mesenteric infarction in the last five years and they get out the starting point in order to check the characteristics of a disease, which is today distinguished by an infaust prognosis. After few mentions about etiopathology and pathologic anatomy they keep their attention on clinic manifestations of disease and on diagnostic research. After dealing with medical and surgical therapy they declare how more refined diagnostic technique could help early diagnosis and consequently decrease morbidity and morbidity, which are completely unacceptable. 相似文献
77.
Andrea Loreti Abate Ornella Floriana Arelli Diana Spallone Edoardo Bruno Pietro De Luca Leopoldo Costarelli Angelo Camaioni 《Clinical Case Reports》2022,10(8)
Mucoepidermoid Carcinoma (MEC) it can origin from a mandibular odontogenic cyst. We report the case of a 63‐year‐old man with MEC of the right retromolar trigonum of the mandibula. We performed a wide mandibular excision and immediate reconstruction with a fibula bone free flap. 相似文献
78.
79.
Gianluca Coppola Ilenia Corbelli Antonio Di Renzo Andrea Chiappiniello Pietro Chiarini Vincenzo Parisi Giorgio Guercini Paolo Calabresi Roberto Tarducci Paola Sarchielli 《The journal of headache and pain》2022,23(1)
IntroductionSeveral functional neuroimaging studies on healthy controls and patients with migraine with aura have shown that the activation of functional networks during visual stimulation is not restricted to the striate system, but also includes several extrastriate networks.MethodsBefore and after 4 min of visual stimulation with a checkerboard pattern, we collected functional MRI in 21 migraine with aura (MwA) patients and 18 healthy subjects (HS). For each recording session, we identified independent resting-state networks in each group and correlated network connection strength changes with clinical disease features.ResultsBefore visual stimulation, we found reduced connectivity between the default mode network and the left dorsal attention system (DAS) in MwA patients compared to HS. In HS, visual stimulation increases functional connectivity between the independent components of the bilateral DAS and the executive control network (ECN). In MwA, visual stimulation significantly improved functional connectivity between the independent component pairs salience network and DAS, and between DAS and ECN. The ECN Z-scores after visual stimulation were negatively related to the monthly frequency of aura.ConclusionsIn individuals with MwA, 4 min of visual stimulation had stronger cognitive impact than in healthy people. A higher frequency of aura may lead to a diminished ability to obtain cognitive resources to cope with transitory but important events like aura-related focal neurological symptoms. 相似文献
80.
Roberto Orecchia Umberto Veronesi Patrick Maisonneuve Viviana Enrica Galimberti Roberta Lazzari Paolo Veronesi Barbara Alicja Jereczek-Fossa Federica Cattani Claudia Sangalli Alberto Luini Pietro Caldarella Marco Venturino Daniele Sances Stefano Zurrida Giuseppe Viale Maria Cristina Leonardi Mattia Intra 《The lancet oncology》2021,22(5):597-608