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1.
Pharmazie ; 78(8): 117-121, 2023 08 01.
Article de Anglais | MEDLINE | ID: mdl-37592422

RÉSUMÉ

Enteral nutrients (ENs) affect the plasma drug concentration of orally co-administered drugs, particularly those of antiepileptic drugs, such as phenytoin and carbamazepine. However, few studies have reported the interactions of levetiracetam (LEV), an upcoming antiepileptic drug, with ENs. In this study we aimed to investigate the pharmacokinetics of LEV in 55 rats after oral co-administration of LEV with liquid or semisolid ENs. Compared with the control group, co-administration with Terumeal ® Soft significantly decreased the plasma LEV concentration at 0.5, 1, and 2 h and area under the plasma concentration-time curve from 0 to 3 h (AUC0→3h) (P < 0.01). However, the AUC0→3h of LEV remained unchanged following the administration of Terumeal ® Soft 2 h after the initial LEV administration. Moreover, co-administration with semisolid Racol® NF delayed the absorption of LEV without decreasing the AUC0→3h, whereas liquid Racol ® NF did not alter LEV pharmacokinetics. Thus, co-administration of LEV with Terumeal® Soft reduced the absorption of LEV from the gastrointestinal tract, which was prevented by administering Terumeal ® Soft 2 h after LEV administration. Semisolid Racol ® NF altered LEV pharmacokinetics without decreasing its gastrointestinal absorption. Our findings suggested that careful monitoring of the plasma LEV levels is necessary when co-administering LEV with Terumeal ® Soft, semisolid Racol ® NF, or any other semisolid ENs, to prevent the inadvertent effects of the interaction between LEV and ENs.


Sujet(s)
Anticonvulsivants , Tube digestif , Animaux , Rats , Lévétiracétam/pharmacologie , Administration par voie orale , Nutriments
2.
Pharmazie ; 74(9): 559-562, 2019 09 01.
Article de Anglais | MEDLINE | ID: mdl-31484597

RÉSUMÉ

The gastrointestinal absorption of phenytoin (PHT), an antiepileptic drug, is often affected by its interaction with co-administered enteral nutrients through a nasogastric (NG) tube, resulting in decreased plasma PHT concentration. In this study, we measured the recovery rate (%) of PHT (Aleviatin® powder) passed through an NG tube when co-administered with distilled water or enteral nutrients (F2α®, Racol® NF, Ensure Liquid® and Renalen® LP). We also measured plasma PHT levels in rats, after oral co-administration of PHT with enteral nutrients. We demonstrate that PHT recovery rate was close to 100 % in all cases after passage through the NG tube. In the rat study, the AUC0→∞ of PHT concentration after oral administration significantly decreased when it was co-administered with F2α® and Racol® NF compared to distilled water. However, the AUC0→∞ of PHT was unchanged when co-administered with F2α® 2 h after initial PHT administration. We therefore conclude that the co-administration of PHT with F2α® and Racol® NF caused a reduction in the absorption of PHT from the gastrointestinal tract to the blood, without adsorption to the NG tube. The administration of enteral nutrients 2 h after PHT is one clear way to prevent a decrease in plasma PHT concentration.


Sujet(s)
Anticonvulsivants/pharmacocinétique , Nutrition entérale , Interactions aliments-médicaments , Phénytoïne/pharmacocinétique , Administration par voie orale , Animaux , Anticonvulsivants/administration et posologie , Aire sous la courbe , Absorption gastro-intestinale , Mâle , Phénytoïne/administration et posologie , Rats , Rat Sprague-Dawley
3.
Ann Oncol ; 26(7): 1427-33, 2015 Jul.
Article de Anglais | MEDLINE | ID: mdl-25908603

RÉSUMÉ

BACKGROUND: A targeted agent combined with chemotherapy is the standard treatment in patients with metastatic colorectal cancer (mCRC). The present phase III study was conducted to compare two doses of bevacizumab combined with irinotecan, 5-fluorouracil/leucovorin (FOLFIRI) in the second-line setting after first-line therapy with bevacizumab plus oxaliplatin-based therapy. PATIENTS AND METHODS: Patients were randomly assigned to receive FOLFIRI plus bevacizumab 5 or 10 mg/kg in 2-week cycles until disease progression. The primary end point was progression-free survival (PFS), and secondary end points included overall survival (OS), time to treatment failure (TTF), and safety. RESULTS: Three hundred and eighty-seven patients were randomized between September 2009 and January 2012 from 100 institutions in Japan. Baseline patient characteristics were well balanced between the two groups. Efficacy was evaluated in 369 patients (5 mg/kg, n = 181 and 10 mg/kg, n = 188). Safety was evaluated in 365 patients (5 mg/kg, n = 180 and 10 mg/kg, n = 185). The median PFS was 6.1 versus 6.4 months (hazard ratio, 0.95; 95% confidence interval [CI] 0.75-1.21; P = 0.676), and median TTF was 5.2 versus 5.2 months (hazard ratio, 1.01; 95% CI 0.81-1.25; P = 0.967), respectively, for the bevacizumab 5 and 10 mg/kg groups. Follow-up of OS is currently ongoing. Adverse events, including hypertension and hemorrhage, occurred at similar rates in both groups. CONCLUSION: Bevacizumab 10 mg/kg plus FOLFIRI as the second-line treatment did not prolong PFS compared with bevacizumab 5 mg/kg plus FOLFIRI in patients with mCRC. If bevacizumab is continued after first-line therapy in mCRC, a dose of 5 mg/kg is appropriate for use as second-line treatment. CLINICAL TRIAL IDENTIFIER: UMIN000002557.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Tumeurs colorectales/traitement médicamenteux , Récidive tumorale locale/traitement médicamenteux , Thérapie de rattrapage , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Bévacizumab/administration et posologie , Camptothécine/administration et posologie , Camptothécine/analogues et dérivés , Tumeurs colorectales/mortalité , Tumeurs colorectales/anatomopathologie , Femelle , Fluorouracil/administration et posologie , Études de suivi , Humains , Irinotécan , Leucovorine/administration et posologie , Mâle , Adulte d'âge moyen , Métastase tumorale , Récidive tumorale locale/mortalité , Récidive tumorale locale/anatomopathologie , Stadification tumorale , Composés organiques du platine/administration et posologie , Oxaliplatine , Pronostic , Taux de survie
6.
J Lab Clin Med ; 139(1): 35-42, 2002 Jan.
Article de Anglais | MEDLINE | ID: mdl-11873243

RÉSUMÉ

The implantation of nonautologous cells encapsulated in immunoprotective microcapsules provides an alternative nonviral method for gene therapy. This strategy was successful in reversing the disease phenotypes of dwarfism and a lysosomal storage disease, mucopolysaccharidosis VII, in murine models. In this article we implanted transgenic hemophilic B mice with microcapsules enclosing factor IX-secreting C2C12 myoblasts to study the clinical potential of this approach in the treatment of hemophilia. Treated mice showed increased plasma factor IX levels as high as 28 ng of human factor IX per milliliter of plasma and decreased activated thromboplastin times (reduced by 20% to 29%). However, the level of factor IX decreased to baseline levels by day 7, coinciding with emergence of anti-human factor IX antibody, the titer of which increased greater than 10-fold by day 28. Monoclonal anti-CD4 antibodies were used to deplete CD4+ T cells to suppress the immune response against the recombinant factor IX. In the treated hemophilic mice, the anti-factor IX antibody response was totally suppressed to beyond day 28 accompanied by a significant decrease in activated thromboplastin time compared with that seen in untreated hemophilic mice. When the microcapsules were recovered from the intraperitoneal cavity after 38 days of implantation, the encapsulated cells continued to secrete factor IX at preimplantation levels, but both cell viability and microcapsule mechanical stability were reduced. Hence although the polymer chemistry of the microcapsules and cell viability may need to be improved for long-term delivery, nonautologous gene therapy with microencapsulated cells has been shown to be effective, at least for the short-term, in alleviating the hemophilic hemostatic anomaly. Coadministration of an immunosuppressant is effective in inhibiting antibody development against the delivered factor IX and should be considered for recipients at risk of inhibitor development.


Sujet(s)
Facteur IX/génétique , Thérapie génétique , Hémophilie B/thérapie , Animaux , Antigènes CD4/physiologie , Facteur IX/immunologie , Facteur IX/métabolisme , Hémophilie B/sang , Humains , Mâle , Souris , Souris de lignée C57BL , Souris transgéniques , Temps de prothrombine
7.
Nature ; 412(6849): 822-6, 2001 Aug 23.
Article de Anglais | MEDLINE | ID: mdl-11518967

RÉSUMÉ

Prostate cancer is the most frequently diagnosed cancer in American men. Screening for prostate-specific antigen (PSA) has led to earlier detection of prostate cancer, but elevated serum PSA levels may be present in non-malignant conditions such as benign prostatic hyperlasia (BPH). Characterization of gene-expression profiles that molecularly distinguish prostatic neoplasms may identify genes involved in prostate carcinogenesis, elucidate clinical biomarkers, and lead to an improved classification of prostate cancer. Using microarrays of complementary DNA, we examined gene-expression profiles of more than 50 normal and neoplastic prostate specimens and three common prostate-cancer cell lines. Signature expression profiles of normal adjacent prostate (NAP), BPH, localized prostate cancer, and metastatic, hormone-refractory prostate cancer were determined. Here we establish many associations between genes and prostate cancer. We assessed two of these genes-hepsin, a transmembrane serine protease, and pim-1, a serine/threonine kinase-at the protein level using tissue microarrays consisting of over 700 clinically stratified prostate-cancer specimens. Expression of hepsin and pim-1 proteins was significantly correlated with measures of clinical outcome. Thus, the integration of cDNA microarray, high-density tissue microarray, and linked clinical and pathology data is a powerful approach to molecular profiling of human cancer.


Sujet(s)
Marqueurs biologiques tumoraux/métabolisme , Analyse de profil d'expression de gènes , Prostate/métabolisme , Tumeurs de la prostate/métabolisme , Protein-Serine-Threonine Kinases/métabolisme , Protéines proto-oncogènes/métabolisme , Serine endopeptidases/métabolisme , Marqueurs biologiques tumoraux/génétique , ADN complémentaire , ADN tumoral , Humains , Immunohistochimie , Mâle , Séquençage par oligonucléotides en batterie , Pronostic , Tumeurs de la prostate/épidémiologie , Tumeurs de la prostate/génétique , Tumeurs de la prostate/anatomopathologie , Protein-Serine-Threonine Kinases/génétique , Protéines proto-oncogènes/génétique , Protéines proto-oncogènes c-pim-1 , Valeurs de référence , Serine endopeptidases/génétique
8.
J Hepatobiliary Pancreat Surg ; 8(2): 124-9, 2001.
Article de Anglais | MEDLINE | ID: mdl-11455467

RÉSUMÉ

We reviewed our experience with intrahepatic cholangiojejunostomy as a palliative therapy for patients with unresectable malignant diseases involving the ductal confluence or the common hepatic duct. Fifteen patients with malignant biliary obstruction were treated by cholangiojejunostomy at our hospital. Two patients had intrahepatic cholangiocarcinoma, 7 had gallbladder carcinoma, 5 had bile duct carcionoma, and 1 had pancreatic carcinoma. Segment III cholangiojejunostomies were performed in 14 patients and segment V cholangiojejunostomy in 1. Contraindications for surgical resection were locoregional invasion of tumors involving the proper and/or common hepatic artery and portal vein in 15 patients and the presence of hepatic metastases in 6 patients. Liver metastases were detected in 5 of the 7 patients with gallbladder carcinoma. Postoperative complications occurred in 2 patients (13%), but there was no leakage of the cholangioenteric anastomosis in our series. There was no operative mortality after cholangiojejunostomy. Of the 9 patients who survived for more than 6 months after surgery, 7 showed a significant improvement in performance status (PS) (82 +/- 10%) 3 months after the surgery compared with the preoperative PS (70 +/- 7%). Four of the 9 patients had recurrent cholangitis as a late complication, but 4 were completely free from jaundice. Median survival after cholangioenteric bypass was 9 months (range, 2-25 months). With respect to tumor location, the median survival time was 4 months (range, 2-25 months) in patients with gallbladder carcinoma and 15.5 months (range, 12-22 months) in those with bile duct carcinoma. While the median survival period after surgery was only 3 months (range, 2 to 8 months) in the 5 patients with hepatic metastases from gallbladder carcinoma, 2 patients without liver metastasis survived for 9 and 25 months after segment III cholangioenteric bypass. In conclusion, cholangiojejunostomy can provide useful palliation for malignant biliary obstruction when combined with careful patient selection.


Sujet(s)
Tumeurs des canaux biliaires/chirurgie , Conduits biliaires intrahépatiques , Cholangiocarcinome/chirurgie , Jéjunostomie , Hépato-porto-entérostomie , Tumeurs des canaux biliaires/mortalité , Cholangiocarcinome/anatomopathologie , Cholestase/étiologie , Cholestase/thérapie , Drainage , Femelle , Tumeurs de la vésicule biliaire/anatomopathologie , Conduit hépatique commun , Humains , Mâle , Soins palliatifs , Tumeurs du pancréas/anatomopathologie , Sélection de patients , Hépato-porto-entérostomie/effets indésirables , Études rétrospectives
9.
Arch Virol ; 146(3): 601-9, 2001.
Article de Anglais | MEDLINE | ID: mdl-11338393

RÉSUMÉ

The retroviral vectors based on an MFG-type backbone have superior expression characteristics, in part, due to the presence of the retroviral chimeric intron (MFG intron). We tested the hypothesis that inclusion of a second intron in MFG vectors may influence packaging and/or LTR-driven transgene expression. We constructed two MFG retroviral vectors, MFG/hFIXc and MFG/hFIXm2, containing human factor IX (hFIX) cDNA without and with a 0.3-kb hFIX intron, respectively. When tested with primary mouse myoblasts or HepG2 cells in culture for transient expression activity, pMFG/hFIXm2 plasmid produced two-to-three fold higher hFIX than pMFG/hFIXc. These vectors produced equivalent retroviral titers from packaging cells. In transduced cells, the splicing of the MFG intron in the retroviral transcripts occurred at a similar efficiency; however, MFG/hFIXc virus gave two-fold higher hFIX expression than that of the MFG/hFIXm2 viral infection. Analyses of MFG/hFIXm2 virion RNA and transduced cell genomic DNA suggested that, although the hFIX intron containing viral RNA are packaged, these viruses fail to integrate their transgenes into the genome of transduced cells, suggesting a block at the reverse transcription and/or integration steps. Similar results were also obtained with the prototype vectors, LIXcSN and LIXm2SN, lacking the MFG intron. Together, these results suggest that a hFIX cDNA sequence in the retroviral vectors performs better over hFIX intron-containing minigene.


Sujet(s)
Retroviridae/génétique , Animaux , Cellules cultivées , Techniques de transfert de gènes , Vecteurs génétiques , Humains , Introns , Souris , Séquences répétées terminales , Transgènes
10.
Surgery ; 129(4): 421-8, 2001 Apr.
Article de Anglais | MEDLINE | ID: mdl-11283532

RÉSUMÉ

BACKGROUND: Hepatic recurrence is seen in approximately 40% of patients undergoing hepatectomy for colorectal metastases. This study was designed to assess the risks and clinical benefits of repeat hepatectomy for those patients. METHODS: Twenty-six patients underwent repeat hepatectomy for hepatic recurrence, and their clinical data were retrospectively reviewed for operative morbidity and mortality, performance level, and survival. RESULTS: There was no operative mortality after repeat hepatectomy. Operative bleeding was significantly increased in the second hepatectomy; but operating time, duration of hospital stay, and performance status after the second hepatectomy were comparable with those of the initial hepatectomy. The median survival time from the second hepatectomy was 31 months, and the 3- and 5-year survival rates were 62% and 32%, respectively. A short disease-free interval (6 months or less) between the initial hepatectomy and diagnosis of hepatic recurrence in the remnant liver was significantly associated with poor survival after the second hepatectomy. CONCLUSIONS: Repeat resection contributed to clinical benefits for selected patients with hepatic recurrence after the initial hepatectomy for colorectal liver metastases. However, appearance of hepatic recurrence within 6 months or less after the initial hepatectomy is a poor prognostic factor for repeat hepatectomy.


Sujet(s)
Tumeurs colorectales , Hépatectomie/méthodes , Tumeurs du foie/secondaire , Tumeurs du foie/chirurgie , Adulte , Sujet âgé , Tumeurs colorectales/mortalité , Femelle , Hépatectomie/effets indésirables , Humains , Tumeurs du foie/mortalité , Mâle , Adulte d'âge moyen , Complications postopératoires/étiologie , Pronostic , Réintervention , Études rétrospectives , Taux de survie , Facteurs temps
11.
Haemophilia ; 6(6): 713-4, 2000 Nov.
Article de Anglais | MEDLINE | ID: mdl-11122404

RÉSUMÉ

Here we report the successful genetic diagnosis of a pregnant caucasian female patient whose family has a history of moderate haemophilia B. While restriction fragment length polymorphism (RFLP) analysis was not informative, nucleotide sequencing of the factor IX genes of the patient's family members determined that her mother and one of her two sisters were carriers of the mutation C31008T, which causes a Thr296Met transition. In contrast, the pregnant female herself and her other sister were found to carry only normal alleles. Plasma factor IX activity and antigen levels supported these findings.


Sujet(s)
Facteur IX/génétique , Hémophilie B/génétique , Allèles , Femelle , Hétérozygote , Humains , Mâle , Grossesse
12.
Surg Today ; 30(9): 844-8, 2000.
Article de Anglais | MEDLINE | ID: mdl-11039717

RÉSUMÉ

Microwave coagulation therapy (MCT) is one of the treatment modalities for patients with hepatocellular carcinoma (HCC). A 67-year-old man with liver cirrhosis underwent MCT during a laparotomy for a deeply located HCC (2.5 cm in diameter) at the border of the anterior and posterior segments of the right hepatic lobe. Two weeks after MCT, he complained of abdominal fullness. Portal vein thrombosis (PVT) was diagnosed because he had massive ascites and an echogenic mass in the portal vein on abdominal ultrasonography. PVT was successfully treated by fibrinolytic therapy with a selective infusion of urokinase via the superior mesenteric artery (SMA). There have been few reports on PVT as a complication of MCT. Attention should be paid to the possible occurrence of PVT as a critical complication after MCT for liver tumors adjacent to the portal vein. Fibrinolytic therapy via the SMA is thus considered to be an effective approach for PVT after MCT.


Sujet(s)
Carcinome hépatocellulaire/chirurgie , Électrocoagulation/effets indésirables , Tumeurs du foie/chirurgie , Micro-ondes/effets indésirables , Veine porte , Thrombose/étiologie , Sujet âgé , Humains , Mâle , Traitement thrombolytique , Thrombose/traitement médicamenteux , Activateur du plasminogène de type urokinase/usage thérapeutique
13.
Surg Today ; 30(9): 856-60, 2000.
Article de Anglais | MEDLINE | ID: mdl-11039720

RÉSUMÉ

An extremely rare case of a lymphoepithelial cyst (LEC) of the pancreas is described herein. A pancreatic cystic tumor was initially detected in a 50-year-old man at a medical checkup. On admission, his serum carbohydrate antigen (CA) 19-9 level was 8100 U/ml and a computed tomography scan revealed a well-circumscribed multilocular cystic tumor in the pancreatic head and body. Magnetic resonance cholangiopancreatography showed no communication between the pancreatic ducts and the tumor. A distal pancreatectomy with lymph node dissection was performed because the lesion was suspected to be a mucinous cystadenoma or cystadenocarcinoma of the pancreas. However, histological examination revealed that the cyst was lined by stratified squamous epithelium and surrounded by lymphoid tissue. thereby confirming the diagnosis of LEC of the pancreas. The superficial layer of squamous epithelium and the cystic contents were found to be immunohistologically positive for CA19-9. Establishing a preoperative diagnosis of LEC is quite difficult because it resembles other cystic neoplasms of the pancreas in radiographic features and is frequently associated with an elevation of serum tumor markers such as CA19-9.


Sujet(s)
Épithélium/anatomopathologie , Tissu lymphoïde/anatomopathologie , Kyste du pancréas/anatomopathologie , Marqueurs biologiques tumoraux/sang , Antigène CA 19-9/sang , Humains , Mâle , Adulte d'âge moyen
14.
Transplantation ; 69(11): 2267-73, 2000 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-10868624

RÉSUMÉ

BACKGROUND: This study was designed to verify the involvement of platelet-activating factor (PAF) in renal damage associated with hepatic ischemia and reperfusion (HIR) injury through the release of endothelin (ET)-1 and to determine the modulating effect of a specific PAF receptor antagonist on these insults in rats. METHODS: Male rats pretreated with either normal saline as a vehicle (NS group) or intravenous TCV-309, a PAF receptor antagonist (TCV group), were subjected to 120 min of total hepatic ischemia under an extracorporeal portosystemic shunt. Plasma aspartate transaminase, creatinine, blood urea nitrogen, and ET-1 levels and the relative renal wet weight were determined under nonischemic conditions and at 1, 3, and 6 hr of reperfusion after hepatic ischemia. Changes in mean arterial blood pressure and renal tissue blood flow measurements in the kidney were determined throughout the experiment. RESULTS: Increased plasma aspartate transaminase, creatinine, blood urea nitrogen, and ET-1 levels and the relative renal wet weight after HIR in the NS group were significantly suppressed by TCV-309 pretreatment. Mean arterial blood pressure and renal tissue blood flow after HIR in the TCV group were significantly improved when compared with those in the NS group. These effects resulted in attenuation of structural hepatic and renal damage with the improvement of 7-day survival (62%). CONCLUSIONS: The present study demonstrates that renal damage as well as critical liver injury is produced after reperfusion following 120 min of total hepatic ischemia. A PAF receptor antagonist may be therapeutically useful to protect against these types of damage via indirect modulation of plasma ET-1 levels.


Sujet(s)
Endothéline-1/physiologie , Ischémie/anatomopathologie , Rein/anatomopathologie , Circulation hépatique , Facteur d'activation plaquettaire/physiologie , Récepteurs de surface cellulaire , Récepteurs couplés aux protéines G , Lésion d'ischémie-reperfusion/anatomopathologie , Tétrahydroisoquinoléines , Animaux , Aspartate aminotransferases/sang , Pression sanguine , Azote uréique sanguin , Créatinine/sang , Endothéline-1/sang , Isoquinoléines/pharmacologie , Foie/anatomopathologie , Mâle , Antiagrégants plaquettaires/pharmacologie , Glycoprotéines de membrane plaquettaire/antagonistes et inhibiteurs , Composés de pyridinium/pharmacologie , Rats , Rat Sprague-Dawley
15.
J Clin Invest ; 105(11): 1537-45, 2000 Jun.
Article de Anglais | MEDLINE | ID: mdl-10841512

RÉSUMÉ

The PHSRN sequence of the plasma fibronectin (pFn) cell-binding domain induces human keratinocytes and fibroblasts to invade the naturally serum-free extracellular matrices of sea urchin embryos. The potency of acetylated, amidated PHSRN (Ac-PHSRN-NH(2)) is significantly increased, making it more active on a molar basis than the 120-kDa cell-binding domain of pFn. Arginine is important to this activity because PHSAN and PHSEN are inactive, as is a randomized sequence peptide, Ac-HSPNR-NH(2). One treatment with Ac-PHSRN-NH(2) stimulates reepithelialization and contraction of dermal wounds in healing-impaired, obese diabetic C57BL6/KsJ db/db mice. Wound closure is equally rapid in treated db/db and db/+ mice and may be more rapid than in untreated nondiabetic db/+ littermates. In contrast, treatment with either Ac-HSPNR-NH(2) or normal saline (NS) has no effect. Analysis of sectioned db/db wounds shows that, in contrast to treatment with Ac-HSPNR-NH(2) or NS, a single Ac-PHSRN-NH(2) treatment stimulates keratinocyte and fibroblast migration into wounds, enhances fibroplasia and vascularization in the provisional matrix, and stimulates the formation of prominent fibers that may be associated with wound contraction.


Sujet(s)
Facteurs chimiotactiques/pharmacologie , Diabète/physiopathologie , Matrice extracellulaire/effets des médicaments et des substances chimiques , Fibronectines/pharmacologie , Fragments peptidiques/pharmacologie , Cicatrisation de plaie/effets des médicaments et des substances chimiques , Animaux , Sites de fixation , Mouvement cellulaire , Cellules cultivées , Fibroblastes/physiologie , Kératinocytes/physiologie , Souris , Souris de lignée C57BL , Souris obèse , Récepteur fibronectine/physiologie
16.
IUBMB Life ; 49(3): 189-96, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10868909

RÉSUMÉ

Blood coagulation plays a critical role not only in hemostasis but also in many physiological and pathological conditions. Epidemiological studies have shown that blood coagulation capacity in humans increases with age. Towards understanding the underlying mechanisms, the age regulation of factor IX, a key blood coagulation factor, was extensively studied. A series of human factor IX minigenes, consisting of various components of the human factor IX gene, were constructed and subjected to systematic analyses with HepG2 cells in culture and over the entire life span of transgenic mice. These studies identified critical gene structures that are essential for the unique age-dependent expression patterns of the human factor IX gene--one acting by stabilizing gene transcription and another increasing the amount of mRNA present, presumably by augmenting mRNA stability. These studies have set the stage for analyzing the overall age-based regulatory mechanisms of blood coagulation.


Sujet(s)
Coagulation sanguine/physiologie , Facteurs âges , Animaux , Facteur IX/génétique , Facteur IX/métabolisme , Homéostasie , Humains , Souris , Souris transgéniques , Modèles biologiques , Mutagenèse , ARN messager/métabolisme , Relation structure-activité , Transcription génétique , Cellules cancéreuses en culture
17.
Arterioscler Thromb Vasc Biol ; 20(4): 902-6, 2000 Apr.
Article de Anglais | MEDLINE | ID: mdl-10764652

RÉSUMÉ

Blood coagulation capacity increases with age in healthy individuals, apparently because of increases in the plasma concentration of most procoagulant factors. This phenomenon may play an important role in the advancing age-associated increase of cardiovascular diseases and thrombosis. Through longitudinal analyses of transgenic mice, we recently identified 2 critical age-regulatory elements, AE5' and AE3', which are together essential for age regulation of the normal human factor IX (hFIX) gene. AE5', present in the long interspersed repetitive element-derived sequence of the 5' upstream region, containing polyomavirus enhancer activator-3 or a closely related element, is responsible for age-stable expression of the gene and functions in a position-independent manner. AE3', present in the middle of the 3' untranslated region, is responsible for age-associated elevation of hFIX mRNA levels in the liver. Presence of both AE5' and AE3' is needed to recapitulate normal age regulation of the hFIX gene. Because factor IX clearance from the circulation is not significantly affected by age, age regulation of hFIX levels is achieved primarily by a combination of stabilization of gene transcription and age-dependent increases in the mRNA levels, which are presumably due to increasing mRNA stabilization. The stage is now set for further systematic studies of the genetic and molecular mechanisms of age regulation of other key coagulation and anticoagulation factors in hopes of understanding the overall age regulation of blood coagulation.


Sujet(s)
Vieillissement/physiologie , Coagulation sanguine/génétique , Coagulation sanguine/physiologie , Facteur IX/génétique , Animaux , Régulation de l'expression des gènes , Humains , Souris , Souris transgéniques
18.
J Virol ; 74(8): 3555-65, 2000 Apr.
Article de Anglais | MEDLINE | ID: mdl-10729130

RÉSUMÉ

Recombinant adeno-associated virus (rAAV) vectors have been shown to be useful for efficient gene delivery to a variety of dividing and nondividing cells. Mechanisms responsible for the long-term, persistent expression of the rAAV transgene are not well understood. In this study we investigated the kinetics of rAAV-mediated human factor IX (hFIX) gene transfer into human primary myoblasts and myotubes. Transduction of both myoblasts and myotubes occured with a similar and high efficiency. After 3 to 4 weeks of transduction, rAAV with a cytomegalovirus (CMV) promoter showed 10- to 15-fold higher expression than that with a muscle-specific creatine kinase enhancer linked to beta-actin promoter. Factor IX expression from transduced myoblasts as well as myotubes reached levels as high as approximately 2 microgram of hFIX/10(6) cells/day. Southern blot analyses of high-molecular-weight (HMW) cellular genomic and Hirt DNAs isolated from rAAV/CMVhFIXm1-transduced cells showed that the conversion of single-stranded vector genomes to double-stranded DNA forms, but not the level of the integrated forms in HMW DNA, correlated with increasing expression of the transgene. Together, these results indicate that rAAV can transduce both proliferating and terminally differentiated muscle cells at about the same efficiency, that expression of transgenes increases linearly over their lifetime with no initial lag phase, and that increasing expression correlates with the appearance of double-stranded episomal rAAV genomes. Evidence showing that the rAAV virions can copackage hFIX, presumably nonspecifically, was also obtained.


Sujet(s)
Dependovirus/génétique , Facteur IX/génétique , Techniques de transfert de gènes , Vecteurs génétiques , Muscles squelettiques/cytologie , Transgènes , Technique de Southern , Technique de Western , Division cellulaire , Cellules cultivées , ADN/génétique , ADN simple brin/génétique , ADN viral/génétique , Expression des gènes , Humains , Cinétique , Muscles squelettiques/métabolisme , Transfection , Virion/génétique
19.
Cancer Res ; 60(2): 309-20, 2000 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-10667582

RÉSUMÉ

Using naturally serum-free SU-ECM basement membranes as invasion substrates showed that plasma fibronectin was necessary to stimulate invasion by DU 145 human and metastatic MATLyLu (MLL) rat prostate carcinoma cells. This activity mapped to the PHSRN sequence, which induced invasion through alpha5beta1 integrin. PHSCN, a competitive inhibitor, blocked both PHSRN- and serum-induced invasion. Acetylated, amidated PHSCN (Ac-PHSCN-NH2) was 30-fold more potent; however, Ac-HSPNC-NH2 was inactive. Rats receiving injections s.c. with 100,000 MLL cells were treated systemically by i.v. injection three times weekly with 1 mg of either Ac-PHSCN-NH2 or Ac-HSPNC-NH2 beginning 24 h later, three times weekly with 1 mg of Ac-PHSCN-NH2 beginning only after surgery to remove large (2 cm) MLL tumors, or were left untreated. MLL tumors grew rapidly in Ac-HSPNC-NH2-treated and in untreated rats. MLL tumor growth in rats treated with Ac-PHSCN-NH2 beginning 1 day after MLL cell injection was reduced by 99.9% during the first 16 days of treatment, although subsequent tumor growth occurred. MLL tumor cryosections immunostained with anti-PECAM-1 showed that Ac-PHSCN-NH2 inhibited neovascularization by 12-fold during this time. Whether initiated after MLL cell injection or only after MLL tumor removal, Ac-PHSCN-NH2 treatment reduced the numbers of MLL lung colonies and micrometastases by 40- to >100-fold, whereas Ac-HSPNC-NH2 was inactive. Thus, Ac-PHSCN-NH2 may be a potent antitumorigenic and antimetastatic agent for postsurgical use prior to extensive metastasis.


Sujet(s)
Antinéoplasiques/toxicité , Fibronectines/physiologie , Tumeurs du poumon/secondaire , Oligopeptides/toxicité , Tumeurs de la prostate/vascularisation , Tumeurs de la prostate/anatomopathologie , Séquence d'acides aminés , Animaux , Membrane basale , Survie cellulaire/effets des médicaments et des substances chimiques , Chimiotaxie/effets des médicaments et des substances chimiques , Fibronectines/composition chimique , Humains , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/prévention et contrôle , Mâle , Invasion tumorale , Métastase tumorale , Tumeurs de la prostate/traitement médicamenteux , Rats , Récepteur fibronectine/physiologie , Relation structure-activité , Cellules cancéreuses en culture
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