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2.
Eur Rev Med Pharmacol Sci ; 24(13): 7211, 2020 07.
Article de Anglais | MEDLINE | ID: mdl-32706049

RÉSUMÉ

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Long noncoding RNA DARS-AS1 acts as an oncogene by targeting miR-532-3p in ovarian cancer, by K. Huang, W.-S. Fan, X.-Y. Fu, Y.-L. Li, Y.-G. Meng, published in Eur Rev Med Pharmacol Sci 2019; 23 (6): 2353-2359. DOI: 10.26355/eurrev_201903_17379. PMID: 30964159" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/17379.

4.
Eur Rev Med Pharmacol Sci ; 23(6): 2353-2359, 2019 Mar.
Article de Anglais | MEDLINE | ID: mdl-30964159

RÉSUMÉ

OBJECTIVE: Ovarian cancer is one of the most ordinary malignant tumors. Recently, the role of long noncoding RNAs (lncRNAs) in tumor progression has caught attention of numerous researchers. In this research, lncRNA DARS-AS1 was studied to identify how it functions in the development of ovarian cancer. PATIENTS AND METHODS: DARS-AS1 expression was detected by Real-time quantitative polymerase chain reaction (RT-qPCR) in ovarian cancer tissue samples. Moreover, functional experiments were conducted to detect the effect of DARS-AS1 on the proliferation and metastasis of ovarian cancer. In addition, the underlying mechanism was explored through luciferase assay and RNA immunoprecipitation (RIP) assay. RESULTS: In this study, DARS-AS1 expression was remarkably higher in ovarian cancer tissues compared with that in adjacent ones. Cell proliferation was inhibited after DARS-AS1 silenced in ovarian cancer cells. Moreover, cell migration and invasion were also inhibited after DARS-AS1 silenced in ovarian cancer cells. Furthermore, results of luciferase assays and RIP assay showed that microRNA-532-3p (miR-532-3p) was a direct target of DARS-AS1 in ovarian cancer. The expression of miR-532-3p was upregulated after DARS-AS1 was knocked down. CONCLUSIONS: Our study suggests that DARS-AS1 enhances cell proliferation and metastasis via sponging miR-532-3p in ovarian cancer.

5.
Zhonghua Fu Chan Ke Za Zhi ; 52(10): 679-686, 2017 Oct 25.
Article de Chinois | MEDLINE | ID: mdl-29060966

RÉSUMÉ

Objective: To compare the dose, clinical efficacy and acute adverse reactions of intensity modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) combined with three-dimensional brachytherapy (3D-BT) in the treatment of concurrent radiotherapy and chemotherapy for advanced stage cervical cancer patients. Methods: Data collection was performed from January 2011 to November 2015 in Chinese PLA General Hospital and Inner Mongolia Cancer Hospital. All 89 patients with advanced stage (Ⅱ b-Ⅲ b) cervical cancer were treated by pelvic radiotherapy and concurrent chemotherapy, 46 cases of them received IMRT and 3D-BT (IMRT group) , 43 cases received 3D-CRT and 3D-BT (3D-CRT group) , along with cisplatin chemotherapy. The dose accumulation of external beam radiotherapy and 3D-BT was calculated by deformable image registration to analyze clinical efficacy, acute adverse reactions and prognosis of the two groups. Results: (1) Dose of radiotherapy: planning target volume (PTV) coverage of IMRT group and 3D-CRT group were respectively (95.4±4.7)% and (95.1±5.1)%, without significant differences (t=0.289, P=0.773). Compared with the patients treated with 3D-CRT, the volumn receiving at least 30 Gy (V(30)), V(50) of rectum, colon, bladder and small intestine and V(20) of bone marrow in the IMRT group were significantly decreased (P<0.05). Regarding the combined dose, the maximum dose (D(max)) and the minimum dose received by the most exposed 2 cm(3) volume of the analyzed organ (D(2CC)) of rectum, colon, bladder and small intestine of IMRT group were significantly lower than those of 3D-CRT group (P<0.05). (2) Short-term efficacy: the effective rate of IMRT and 3D-CRT group were respectively 93% (43/46) and 91% (39/43), with no significant differences (χ(2)=0.237, P=0.626). (3) Acute adverse reactions: compared with 3D-CRT, IMRT could significantly reduce grade 1-2 acute toxicity in gastrointestinal [63%(29/46) vs 84%(36/43)], genitourinary [17%(8/46) vs 37%(16/43)] and hematologic [57%(26/46) vs 79%(34/43)] system (all P<0.05). There were no significant differences of grade 3 acute adverse reactions of gastrointestinal, genitourinary and hematologic system between two groups (all P>0.05). No grade 4 acute adverse reactions were observed. (4) Prognosis: the overall survival rate at 1, 2-year of IMRT and 3D-CRT group were respectively 95.6%, 89.1% and 93.1%, 86.1%. The progression-free survival rateat 1, 2-year of IMRT and 3D-CRT group were 91.1%, 89.1% and 88.4%, 86.1%, respectively. There were no significant differences in overall survival rate and progression-free survival rate between two groups (P>0.05). Conclusions: Compared with 3D-CRT, IMRT combined with 3D-BT has dosimetry advantages based on dose accumulation algorithms by deformable image registration. IMRT could ensure clinical efficacy and significantly reduce the incidence rate of acute toxicities.


Sujet(s)
Curiethérapie , Cisplatine/usage thérapeutique , Planification de radiothérapie assistée par ordinateur/méthodes , Radiothérapie conformationnelle/méthodes , Radiothérapie conformationnelle avec modulation d'intensité/méthodes , Tumeurs du col de l'utérus/thérapie , Chine , Survie sans rechute , Femelle , Humains , Pelvis , Pronostic , Dosimétrie en radiothérapie , Radiothérapie conformationnelle/effets indésirables , Radiothérapie conformationnelle avec modulation d'intensité/effets indésirables , Rectum/effets des radiations , Indice de gravité de la maladie , Taux de survie , Vessie urinaire/effets des radiations , Appareil urogénital/effets des radiations , Tumeurs du col de l'utérus/mortalité , Tumeurs du col de l'utérus/anatomopathologie
6.
Zhonghua Yi Xue Za Zhi ; 97(13): 982-985, 2017 Apr 04.
Article de Chinois | MEDLINE | ID: mdl-28395414

RÉSUMÉ

Objectives: To evaluate the feasibility and safety of robotic system in early ovarian cancer surgery. Methods: The clinical data of 131 patients with early ovarian cancer undergoing surgical treatment from November 2014 to November 2015 were reviewed retrospectively. There were 27 cases of early ovarian cancer, of which 9 cases of robotic group, 10 cases of laparoscopic group, 8 cases of laparotomy group. Age, Body Mass Index (BMI), preoperative neoadjuvant chemotherapy, operating time, operating method, intraoperative blood loss, intraoperative and postoperative complications, pathological type, lymph node dissection, postoperative exhaust time and postoperative hospital stay of all the patients were analyzed. Results: In the robot group, the mean operating time was( 251.4±58.7) minutes, the intraoperative blood loss was (208.9±202.7) ml, and the number of the main abdominal and pelvic lymph nodes was 27.8±8.9. The mean postoperative hospital stay was (11.1±3.5) days, and the mean postoperative hospital stay was( 2.0±0.5) days. All the patients were followed up for 12-24 months. There was no differences were observed among the three groups for operating time, complications, the blood loss, the number of lymph nodes, the hospital stay and survival time (P≥0.05). Conclusion: A robotic approach for the early ovarian cancer is feasible and effective. Compared with traditional laparoscopic surgery and laparotomy, there is no significant difference in operative effect and tumor-free survival. The robotic approach provides a new method for surgical treatment of early ovarian cancer.


Sujet(s)
Laparotomie , Tumeurs de l'ovaire/chirurgie , Interventions chirurgicales robotisées , Femelle , Humains , Laparoscopie , Lymphadénectomie , Études rétrospectives , Robotique , Résultat thérapeutique
7.
Zhonghua Fu Chan Ke Za Zhi ; 52(2): 86-92, 2017 Feb 25.
Article de Chinois | MEDLINE | ID: mdl-28253570

RÉSUMÉ

Objective: To analyze the clinical features and to explore the etiology of short fetal femur during the third trimester. Methods: From January 2010 to June 2016, 21 singleton pregnancies with short fetal femur detected by ultrasonography during the third trimester were referred to the Chinese PLA General Hospital. Clinical data were collected, karyotype or single nucleotide polymorphism microarray was carried out to detect chromosomal abnormalities, and FGFR3 c.1138G>A mutation detection was carried out to detect achondroplasia (ACH) via invasive procedure, respectively. The deviation of femur length from the mean value of the gestational age in ultrasonography was expressed as the Z-score. The difference between ACH and isolated short femur (ISF, in the absence of associated structure abnormality or genetic abnormality) was then explored. Results: In the 21 fetuses, 11 had abnormal genetic test results(52%, 11/21), including 9 cases of ACH, 1 case of Ellis-van Creveld Syndrome and 1 case of Pallister-Killian syndrome. In the 10 ISF fetuses (48%, 10/21), 3 cases were fetal growth restriction, 1 was normal small for gestational age infant and 6 cases were unexplained. The median Z-scores for 9 cases of ACH and 10 cases of ISF in the third trimester were -5.04, -3.20, respectively. The short femur in ACH was more severe than in ISF (P=0.005) in the third trimester. Conclusions: The etiology of short fetal femur is complicated, including skeletal dysplasia, chromosomal abnormality, fetal growth restriction, as well as normal variants during fetal development. Genetic test should be considered during the antenatal consultation.


Sujet(s)
Dysplasies osseuses/imagerie diagnostique , Fémur/malformations , Fémur/imagerie diagnostique , Retard de croissance intra-utérin/imagerie diagnostique , Échographie prénatale , Achondroplasie , Dysplasies osseuses/génétique , Aberrations des chromosomes , Maladies chromosomiques , Chromosomes humains de la paire 12 , Femelle , Fémur/embryologie , Développement foetal , Retard de croissance intra-utérin/étiologie , Foetus , Âge gestationnel , Humains , Caryotypage , Analyse sur microréseau , Polymorphisme de nucléotide simple , Grossesse , Deuxième trimestre de grossesse , Troisième trimestre de grossesse , Récepteur de type 3 des facteurs de croissance fibroblastique/métabolisme
8.
Eur J Obstet Gynecol Reprod Biol ; 183: 64-9, 2014 Dec.
Article de Anglais | MEDLINE | ID: mdl-25461355

RÉSUMÉ

OBJECTIVES: p16, a tumour suppressor, is unable to express its suppressive effects following interaction with E7-retinoblastoma protein. Previous reports have suggested that p16 immunostaining allows precise identification of cervical intra-epithelial neoplasia and cervical cancer lesions in biopsies. The prognostic value of p16 expression in cervical cancers has been evaluated for several years, but the results remain controversial. As such, the authors undertook a systematic review and meta-analysis of studies assessing the impact of p16 expression on overall survival and disease-free survival. STUDY DESIGN: Medline, Embase and China National Knowledge Infrastructures were searched to identify studies on the prognostic impact of p16 expression in patients with cervical cancer. In total, 1070 patients from 10 eligible studies were included in the analysis. Pooled risk ratios (RRs) with 95% confidence intervals (95% CI) were calculated. RESULTS: A significant association was found between p16 expression and increased disease-free survival (RR 0.60; 95% CI 0.44-0.82; p=0.001). However, no significant association was found between p16 and overall survival. CONCLUSION: p16 expression may be predictive of a favourable prognosis in patients with cervical cancer. However, large-scale, multicentre and well-matched cohort studies are warranted to confirm this finding.


Sujet(s)
Marqueurs biologiques tumoraux/métabolisme , Protéines tumorales/métabolisme , Dysplasie du col utérin/métabolisme , Dysplasie du col utérin/mortalité , Tumeurs du col de l'utérus/métabolisme , Tumeurs du col de l'utérus/mortalité , Marqueurs biologiques tumoraux/génétique , Biopsie , Inhibiteur p16 de kinase cycline-dépendante , Femelle , Régulation de l'expression des gènes tumoraux , Humains , Protéines tumorales/génétique , Stadification tumorale , Valeur prédictive des tests , Pronostic , Taux de survie , Tumeurs du col de l'utérus/anatomopathologie , Dysplasie du col utérin/anatomopathologie
9.
Endocr Relat Cancer ; 16(1): 139-53, 2009 Mar.
Article de Anglais | MEDLINE | ID: mdl-19022849

RÉSUMÉ

LRP16 is a special member of the macro domain superfamily, containing only a stand-alone macro domain functional module. Previous study demonstrated that the estrogenically regulated LRP16 cooperates with the estrogen receptor alpha and enhances the receptor's transcriptional activity in an estrogen-dependent manner. Here, we discovered that LRP16 binds to androgen receptor (AR) via its macro domain and amplifies the transactivation function of AR in response to androgen. Similarly, we also discovered that LRP16 acts as a potential coactivator to amplify the transactivation of at least other four nuclear receptors (NRs). Importantly, we show that the single macro domain in LRP16 can serve as the AR coactivator. RNA interference knockdown of LRP16 leads to impaired AR function and greatly attenuates the coactivation of AR by other AR coactivators such as ART-27 and steroid receptor coactivator-1. This interference also markedly inhibits the androgen-stimulated proliferation of androgen-sensitive LNCaP prostate cancer cells. However, LRP16 knockdown did not significantly affect the growth rate of AR-negative PC-3 prostate cancer cells. Furthermore, we observed the induction effect of LRP16 expression by androgen and established a feedforward mechanism that activated AR transactivation. Our results suggest that the macro domain protein LRP16 represents a novel type of cofactor of NR. They also indicate that LRP16 plays an essential role in AR transactivation.


Sujet(s)
Tumeurs du sein/métabolisme , Protéines tumorales/génétique , Protéines tumorales/métabolisme , Tumeurs de la prostate/métabolisme , Récepteurs aux androgènes/métabolisme , Tumeurs du sein/anatomopathologie , Carboxylic ester hydrolases , Protéines du cycle cellulaire , Division cellulaire/physiologie , Lignée cellulaire tumorale , Système acellulaire , Femelle , Régulation de l'expression des gènes tumoraux , Histone acetyltransferases/métabolisme , Humains , Ligands , Luciferases/génétique , Mâle , Chaperons moléculaires , Protéines tumorales/composition chimique , Coactivateur-1 de récepteur nucléaire , Régions promotrices (génétique)/physiologie , Tumeurs de la prostate/anatomopathologie , Structure tertiaire des protéines , Petit ARN interférent , Facteurs de transcription/métabolisme , Activation de la transcription , Régulation positive/physiologie
10.
Endocr Relat Cancer ; 14(3): 741-53, 2007 Sep.
Article de Anglais | MEDLINE | ID: mdl-17914104

RÉSUMÉ

Previous studies have shown that leukemia related protein 16 (LRP16) is estrogenically regulated and that it can stimulate the proliferation of MCF-7 breast cancer cells, but there are no data on the mechanism of this pathway. Here, we demonstrate that the LRP16 expression is estrogen dependent in several epithelium-derived tumor cells. In addition, the suppression of the endogenous LRP16 in estrogen receptor alpha (ERalpha)-positive MCF-7 cells not only inhibits cells growth, but also significantly attenuates the cell line's estrogen-responsive proliferation ability. However, ectopic expression of LRP16 in ERalpha-negative MDA-MB-231 cells has no effect on proliferation. These data suggest the involvement of LRP16 in estrogen signaling. We also provide novel evidence by both ectopic expression and small interfering RNA knockdown approaches that LRP16 enhances ERalpha-mediated transcription activity. In stably LRP16-inhibitory MCF-7 cells, the estrogen-induced upregulation of several well-known ERalpha target genes including cyclin D1 and c-myc is obviously impaired. Results from glutathione S-transferase pull-down and coimmunoprecipitation assays revealed that LRP16 physically interacts with ERalpha in a manner that is estrogen independent but is enhanced by estrogen. Furthermore, a mammalian two-hybrid assay indicated that the binding region of LRP16 localizes to the A/B activation function 1 domain of ERalpha. Taken together, these results present new data supporting a role for estrogenically regulated LRP16 as an ERalpha coactivator, providing a positive feedback regulatory loop for ERalpha signal transduction.


Sujet(s)
Récepteur alpha des oestrogènes/métabolisme , Oestrogènes/pharmacologie , Régulation de l'expression des gènes tumoraux/effets des médicaments et des substances chimiques , Protéines tumorales/génétique , Protéines tumorales/métabolisme , Activation de la transcription , Tumeurs du sein/génétique , Tumeurs du sein/anatomopathologie , Carboxylic ester hydrolases , Prolifération cellulaire/effets des médicaments et des substances chimiques , Récepteur alpha des oestrogènes/composition chimique , Humains , Liaison aux protéines , Structure tertiaire des protéines , Transactivateurs/génétique , Transactivateurs/métabolisme , Activation de la transcription/effets des médicaments et des substances chimiques , Activation de la transcription/génétique , Transfection , Cellules cancéreuses en culture , Régulation positive/effets des médicaments et des substances chimiques
11.
Biochem Soc Trans ; 30(4): 487-90, 2002 Aug.
Article de Anglais | MEDLINE | ID: mdl-12196120

RÉSUMÉ

The binding sites on human IgG1 for human Fc gamma receptor (Fc gamma R) I, Fc gamma RIIa, Fc gamma RIIb, Fc gamma RIIIa and neonatal FcR have been mapped. A common set of IgG1 residues is involved in binding to all Fc gamma Rs, while Fc gamma RII and Fc gamma RIII utilize distinct sites outside this common set. In addition to residues which abrogated binding to the Fc gamma R, several positions were found which improved binding only to specific Fc gamma Rs or simultaneously improved binding to one type of Fc gamma R and reduced binding to another type. Selected IgG1 variants with improved binding to Fc gamma RIIIa were then tested in an in vitro antibody-dependent cellular cytotoxicity (ADCC) assay and showed an enhancement in ADCC when either peripheral blood mononuclear cells or natural killer cells were used.


Sujet(s)
Anticorps monoclonaux/immunologie , Génie génétique/méthodes , Récepteurs du fragment Fc des IgG/immunologie , Anticorps monoclonaux/génétique , Cytotoxicité à médiation cellulaire dépendante des anticorps , Lymphocytes B/immunologie , Humains , Immunoglobuline G/génétique , Immunoglobuline G/immunologie , Cellules tueuses naturelles/immunologie , Protéines de fusion recombinantes/génétique , Protéines de fusion recombinantes/immunologie
12.
Space Med Med Eng (Beijing) ; 14(4): 282-5, 2001 Aug.
Article de Chinois | MEDLINE | ID: mdl-11681343

RÉSUMÉ

OBJECTIVE: To evaluate the friction property of diamond-like carbon (DLC) film/Ti6Al4V gradient material sliding against UHMWPE couple. METHOD: Tests of this couple were made under dry sliding and lubrication of Hank's solution and 0.9% NaCl solution respectively, and they were compared with the friction property of Ti6Al4V sliding against UHMWPE couple. The tests were performed on an SRV friction and wear tester by means of surface-contact and coefficients of friction were recorded real-time. RESULT: DLC film could reduce the friction coefficient evidently. The coefficients of friction reduced 24%, 5.0%, 10% than these of Ti6Al4V under dry sliding and lubrication of Hank's solution and 0.9% NaCl solution respectively. Mechanism of friction was also studied by observing scanning electrical microscopy (SEM) morphology of frictional surfaces. CONCLUSION: Friction-reduction mechanism of DLC film/Ti6Al4V could be resulted from amorphous structure of DLC film which was smooth and hard.


Sujet(s)
Matériaux biocompatibles , Carbone , Test de matériaux , Polyéthylènes , Friction , Lubrification
13.
Thromb Haemost ; 85(3): 379-89, 2001 Mar.
Article de Anglais | MEDLINE | ID: mdl-11307801

RÉSUMÉ

Blocking the cofactor function of human tissue factor may be beneficial in various coagulation-mediated diseases. The murine antibody D3 binds to the membrane proximal substrate interaction region of human tissue factor and blocks tissue factor function even in the presence of bound factor VIIa. The cloned murine D3 antibody was humanized and affinity matured by exchanging amino acids in the complementarity determining regions as well as in the antibody framework. The humanized antibody, D3H44, bound to tissue factor with a 100-fold increased affinity (KD 0.1 nM) as compared to the original murine and chimeric versions. Depending on the particular disease, different pharmacokinetic properties of the antibody may be required and, therefore, several antibody variants-- F(ab), F(ab')2, IgG2, IgG4 and IgG4b-were generated. In vitro, the humanized D3 antibodies displayed potent inhibition of plasma clotting and tissue factor: factor VIIa-mediated activation of factors IX and X (e.g. D3H44-F(ab')2, IC50(F.X) 47 pM). In addition, D3H44-F(ab')2 completely prevented fibrin deposition in a human ex vivo thrombosis model under venous blood flow conditions (IC50 37 nM). The humanized D3 antibodies may be utilized for treatment of cardiovascular diseases which involve tissue factor activity, e.g. acute coronary syndrome and venous thrombosis.


Sujet(s)
Anticorps monoclonaux/usage thérapeutique , Affinité des anticorps/immunologie , Thromboplastine/immunologie , Séquence d'acides aminés , Animaux , Anticorps monoclonaux/génétique , Anticorps monoclonaux/pharmacologie , Tests de coagulation sanguine , Clonage moléculaire , Facteur IX/effets des médicaments et des substances chimiques , Facteur IX/métabolisme , Facteur X/effets des médicaments et des substances chimiques , Facteur X/métabolisme , Fibrinolytiques/pharmacologie , Fibrinolytiques/usage thérapeutique , Humains , Fragments d'immunoglobuline/génétique , Souris , Données de séquences moléculaires , Protéines de fusion recombinantes/génétique , Protéines de fusion recombinantes/immunologie , Protéines de fusion recombinantes/usage thérapeutique , Alignement de séquences
14.
J Biol Chem ; 276(9): 6591-604, 2001 Mar 02.
Article de Anglais | MEDLINE | ID: mdl-11096108

RÉSUMÉ

Immunoglobulin G (IgG) Fc receptors play a critical role in linking IgG antibody-mediated immune responses with cellular effector functions. A high resolution map of the binding site on human IgG1 for human Fc gamma RI, Fc gamma RIIA, Fc gamma RIIB, Fc gamma RIIIA, and FcRn receptors has been determined. A common set of IgG1 residues is involved in binding to all Fc gamma R; Fc gamma RII and Fc gamma RIII also utilize residues outside this common set. In addition to residues which, when altered, abrogated binding to one or more of the receptors, several residues were found that improved binding only to specific receptors or simultaneously improved binding to one type of receptor and reduced binding to another type. Select IgG1 variants with improved binding to Fc gamma RIIIA exhibited up to 100% enhancement in antibody-dependent cell cytotoxicity using human effector cells; these variants included changes at residues not found at the binding interface in the IgG/Fc gamma RIIIA co-crystal structure (Sondermann, P., Huber, R., Oosthuizen, V., and Jacob, U. (2000) Nature 406, 267-273). These engineered antibodies may have important implications for improving antibody therapeutic efficacy.


Sujet(s)
Immunoglobuline G/composition chimique , Récepteurs du fragment Fc des IgG/composition chimique , Cytotoxicité à médiation cellulaire dépendante des anticorps , Sites de fixation , Cristallisation , Glycosylation , Humains , Immunoglobuline G/classification , Immunoglobuline G/métabolisme , Ingénierie des protéines , Récepteurs du fragment Fc des IgG/métabolisme , Relation structure-activité
15.
Pediatrics ; 105(6): 1286-91, 2000 Jun.
Article de Anglais | MEDLINE | ID: mdl-10835070

RÉSUMÉ

OBJECTIVES: Neonatal thrombocytopenia occurs commonly in neonatal intensive care units. The role of the thrombopoietin (Tpo) system in normal neonatal platelet regulation and neonatal thrombocytopenia is not well understood. The purpose of our study was to: 1) determine the normal Tpo level at birth in healthy nonthrombocytopenic term (NTT) and nonthrombocytopenic preterm (NTP) infants and in infants born to women with preeclampsia; and 2) measure Tpo levels in infants during and after the resolution of thrombocytopenia. Characterizing Tpo levels in the healthy and thrombocytopenic newborn is an important step in furthering our understanding of the pathophysiology of neonatal thrombocytopenia. METHODS: This study is comprised of 2 parts. For the first part, cord blood was obtained at birth from both term (gestational age [GA]: 38-42 weeks) and preterm (GA: 25-36 weeks) infants. If birth platelet levels were >/=140 x 10(3)/microL and the infant fit criteria for being normal, or if the infant was born to a women with preeclampsia, Tpo levels were measured. For the second part, serial Tpo levels and concomitant platelet counts (Plts) were measured in both preterm and term infants during a period of marked thromboctyopenia (Plt < 100 x 10(3)/microL) until its resolution (Plt >/= 140 x 10(3)/microL). RESULTS: Median cord blood Tpo levels from NTP infants (n = 35) were higher than those of NTT infants (n = 32; 95 pg/mL vs 48 pg/mL, respectively). In addition, preterm infants born to women with preeclampsia (n = 11) had lower Tpo levels than NTP infants with a similar GA (<41 pg/mL vs 95 pg/mL). For infants with marked thrombocytopenia, median Tpo levels during thrombocytopenia were similar between term (n = 12) and preterm (n = 14) groups (223 pg/mL and 179 pg/mL, respectively), with the majority of individuals showing a decrease in Tpo with resolution of thrombocytopenia. Within each group, there was large variability in the Tpo response to thrombocytopenia. IMPRESSION: These data show that the Tpo system is intact in NTP and NTT neonates. Preeclampsia may be an example of a disorder that perturbs this system. The great variability in Tpo levels seen in infants during thrombocytopenia may be related to the mechanism of thrombocytopenia. The finding that, in general, Tpo levels decreased with resolution of thrombocytopenia is consistent with what has been described in adults and children.


Sujet(s)
Maladies du prématuré/sang , Thrombopénie/sang , Thrombopoïétine/sang , Femelle , Sang foetal/composition chimique , Humains , Nouveau-né , Prématuré , Mâle , Pré-éclampsie , Grossesse
17.
Gene ; 242(1-2): 201-7, 2000 Jan 25.
Article de Anglais | MEDLINE | ID: mdl-10721713

RÉSUMÉ

Mammalian cells are often used for the expression of recombinant proteins. The process of screening transfected cells randomly for high producing clones is tedious and time consuming. We evaluated using green fluorescent protein (GFP) for selection of high producing clones by fluorescence-activated cell sorter (FACS) to reduce screening effort. We expressed neurotrophin-3 (NT3), deoxyribonuclease (DNase), or vascular endothelial growth factor (VEGF) with GFP in Chinese hamster ovary cells. The vector expressed the desired secreted protein and the selectable marker, dihydrofolate reductase, in one expression unit and the intracellular GFP in a second expression unit. Transfected cells were grown in selection medium and sorted by FACS. High fluorescence clones were obtained and found to produce high amounts of the desired protein; VEGF productivity correlated well with GFP fluorescence in 48 clones. Further studies demonstrated that productivity correlated very well with RNA of the desired protein. For comparison, we randomly picked and screened 144 VEGF clones, and the highest producing VEGF clone obtained produced 0.7 pg/cell/day. In contrast, the highest producing VEGF clone obtained by FACS sorting produced 4.4 pg/cell/day. FACS sorting therefore selected high producing clones efficiently. Since an assay for the desired protein is not required, high producing clones for a protein of unknown function can be obtained by FACS sorting followed by measuring the RNA level of the desired protein in the highly fluorescent clones.


Sujet(s)
Protéines luminescentes/génétique , Animaux , Cellules CHO/métabolisme , Séparation cellulaire , Clones cellulaires , Cricetinae , Facteurs de croissance endothéliale/génétique , Cytométrie en flux , Expression des gènes , Régulation de l'expression des gènes , Protéines à fluorescence verte , Protéines luminescentes/métabolisme , Lymphokines/génétique , Neurotrophine-3/génétique , Protéines de fusion recombinantes/génétique , Protéines de fusion recombinantes/métabolisme , Transfection , Facteur de croissance endothéliale vasculaire de type A , Facteurs de croissance endothéliale vasculaire
18.
Mol Hum Reprod ; 6(3): 269-75, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10694276

RÉSUMÉ

Activated peritoneal macrophages are associated with endometriosis and may play a central role in its aetiology by releasing interleukin-1beta (IL-1beta) in response to refluxed endometrium. Pari passu with the establishment of endometriotic implants is the development of a vascular supply. In this study we investigated the angiogenic properties of two endometrial proteins, vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6), and assessed their production in response to IL-1beta stimulation in human stromal cells isolated from normal endometrium (NE) and endometriotic lesions (EI). Proliferation of bovine brain capillary endothelial cells (BBCE) with a [(3)H]-thymidine incorporation assay was observed when VEGF (2.1 +/- 0.2-fold; P < 0.05) or VEGF and IL-6 (1.8 +/- 0.1-fold; P < 0.05) were added in vitro, relative to saline-treated control cultures. Northern blot analysis showed induction of VEGF mRNA (2.6-fold; P < 0.05) and IL-6 mRNA (6.3-fold; P < 0.05) transcripts in EI cells, but not NE cells, exposed to IL-1beta. A similar induction was seen with VEGF and IL-6 protein secretion in the responsive EI cells. Reverse transcription-polymerase chain reaction (RT-PCR) for the IL-1 receptor type I (IL-1 RI) indicated that the differential effects of IL-1beta on NE and EI cells was associated with 2.4 +/- 0.1-fold more receptor mRNA in EI versus NE cells. We propose that the ability of IL-1beta to activate an angiogenic phenotype in EI stromal cells but not in NE cells, is mediated by the IL-1 RI.


Sujet(s)
Endométriose , Endomètre/métabolisme , Facteurs de croissance endothéliale/biosynthèse , Interleukine-1/pharmacologie , Interleukine-6/biosynthèse , Lymphokines/biosynthèse , Adulte , Agents angiogéniques/pharmacologie , Animaux , Bovins , Cellules cultivées , Endométriose/anatomopathologie , Endomètre/cytologie , Facteurs de croissance endothéliale/génétique , Facteurs de croissance endothéliale/pharmacologie , Femelle , Expression des gènes , Humains , Interleukine-6/génétique , Interleukine-6/pharmacologie , Lymphokines/génétique , Lymphokines/pharmacologie , Phénotype , Récepteurs à l'interleukine-1/génétique , Cellules stromales/effets des médicaments et des substances chimiques , Cellules stromales/métabolisme , Facteur de croissance endothéliale vasculaire de type A , Facteurs de croissance endothéliale vasculaire
19.
J Immunol ; 164(8): 4178-84, 2000 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-10754313

RÉSUMÉ

Rituxan (Rituximab) is a chimeric mAb with human IgG1 constant domains used in the therapy of non-Hodgkin's B cell lymphomas. This Ab targets B cells by binding to the cell-surface receptor, CD20. In our investigation of the mechanism of B cell depletion mediated by Rituximab, we first constructed mutants of Rituximab defective in complement activation but with all other effector functions intact. Our results demonstrate that the previously described C1q binding motif in murine IgG2b constituting residues E318, K320, and K322 is not applicable to a human IgG1 when challenged with either human, rabbit, or guinea pig complement. Alanine substitution at positions E318 and K320 in Rituximab had little or no effect on C1q binding and complement activation, whereas alanine substitution at positions D270, K322, P329, and P331 significantly reduced the ability of Rituximab to bind C1q and activate complement. We have also observed that concentrations of complement approaching physiological levels are able to rescue >60% of the activity of these mutant Abs with low affinity for C1q. These data localize the C1q binding epicenter on human IgG1 and suggest that there are species-specific differences in the C1q binding site of Igs.


Sujet(s)
Anticorps monoclonaux/métabolisme , Sites de fixation des anticorps , Complément C1q/immunologie , Complément C1q/métabolisme , Fragments Fc des immunoglobulines/métabolisme , Immunoglobuline G/métabolisme , Protéines de fusion recombinantes/métabolisme , Alanine/génétique , Substitution d'acide aminé/génétique , Substitution d'acide aminé/immunologie , Animaux , Anticorps monoclonaux/composition chimique , Anticorps monoclonaux/génétique , Anticorps monoclonaux/immunologie , Anticorps monoclonaux d'origine murine , Affinité des anticorps/génétique , Cytotoxicité à médiation cellulaire dépendante des anticorps/génétique , Acide aspartique/génétique , Sites de fixation des anticorps/génétique , Complément C1q/composition chimique , Cochons d'Inde , Humains , Fragments Fc des immunoglobulines/composition chimique , Fragments Fc des immunoglobulines/génétique , Immunoglobuline G/composition chimique , Immunoglobuline G/génétique , Lysine/génétique , Souris , Cartographie peptidique/méthodes , Phénylalanine/génétique , Lapins , Protéines de fusion recombinantes/composition chimique , Protéines de fusion recombinantes/immunologie , Rituximab
20.
Toxicol Sci ; 52(1): 101-6, 1999 Nov.
Article de Anglais | MEDLINE | ID: mdl-10568703

RÉSUMÉ

Poly(lactic-co-glycolic) acid (PLGA) bioresorbable microspheres are used for controlled-release drug delivery and are particularly promising for ocular indications. The objective of the current study was to evaluate the pharmacokinetics and safety of a recombinant human monoclonal antibody (rhuMAb HER2) in rabbits after bolus intravitreal administration of a solution or a PLGA-microsphere formulation. On Day 0, forty-eight male New Zealand white rabbits (2.3-2.6 kg) were immobilized with intramuscular ketamine/xylazine, and the test materials were injected directly into the vitreous compartment. Group 1 animals received rhuMAb HER2 in 50:50 lactide: glycolide PLGA microspheres; Group 2 animals received rhuMAb HER2 in solution (n = 24/group). The dose for each eye was 25 microg (50 microl). After dosing, animals were sacrificed at 2 min, and on 1, 2, 4, 7, 14, 23, 29, 37, 44, 50, and 56 days (n = 2/timepoint/group). Safety assessment included direct ophthalmoscopy, clinical observations, body weight, and hematology and clinical chemistry panels. At necropsy, vitreous and plasma were collected for pharmacokinetics and analysis for antibodies to rhuMAb HER2, and the vitreal pellet (Group 1) was prepared for histologic evaluation. All animals completed the study per protocol-both treatments were well tolerated, and no suppurative or mixed inflammatory cell reaction was observed in the vitreal samples (Group 1) at any of the time points examined. Antibodies to rhuMAb HER2 were detected in plasma samples by Day 7 in both treatment groups, but infrequently in vitreous samples. There were no safety implications associated with this immune response. The in vitro characterization of the PLGA microspheres provided reasonable projections of the in vivo rhuMAb HER2 release kinetics (Group 1). The total amount of antibody that was released was similar in vitro (25.9%) and in vivo (32.4%). RhuMAb HER2 (Group 2) was cleared slowly from the vitreous compartment, with initial and terminal half-lives of 0.9 and 5.6 days, respectively. The volume of distribution approximated the vitreous volume in a rabbit eye.


Sujet(s)
Anticorps monoclonaux/pharmacocinétique , Acide lactique , Acide polyglycolique , Polymères , Animaux , Anticorps monoclonaux/effets indésirables , Matériaux biocompatibles , Systèmes de délivrance de médicaments , Humains , Mâle , Microsphères , Copolymère d'acide poly(lactique-co-glycolique) , Lapins , Solubilité , Solutions , Corps vitré
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