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991.
Laure Voguet Thomas Hbert Jean Levêque Olivier Acker Habiba Mesbah Henri Marret Philippe Pore Gilles Body 《Breast (Edinburgh, Scotland)》2009,18(4):233-237
AimsTo determine factors predictive of the presence of residual tumor on the specimen from mastectomy performed after conservative treatment for breast cancer in order to limit potentially unnecessary mastectomies (free of residual lesions).Materials and methods294 patients treated in 2 expert centers for breast cancer with breast-conserving therapy (BCT) followed by mastectomy, according to French recommendations, were investigated between January 1, 1998 and January 1, 2005. Patients with residual tumor on the mastectomy specimen were compared with patients whose mastectomy specimens did not reveal any residual tumor. All the clinical risk factors (age, previous history of breast cancer, tumor focality) and histological risk factors (tumor size, histological type, positive margins, estrogen and progesterone receptor expression, histological grade) for residual tumor after BCT were compared between the 2 patient groups.ResultsOf the 294 patients studied, 202 (68.71%) mastectomies had residual tumor and 92 (31.29%) were tumor-free. Four predictive factors for residual tumor were found in the univariate analysis: age under 45 years (p = 0.01), absence of estrogen receptor expression (p = 0.05), positive margins (p = 0.01), and presence of lymph node metastases (p = 0.05). The multivariate analysis revealed only 2 independent risk factors that were significantly associated with increased risk of residual tumor on the mastectomy specimen: age under 45 years (p = 0.05) and presence of positive margins on the lumpectomy specimen (p = 0.05).ConclusionYoung age of patients (under 45-years-old) and presence of positive margins on the operative specimen are independent risk factors of residual tumor after conservative treatment of breast cancer. 相似文献
992.
More than 500,000 flexible bronchoscopies are performed annually by chest physicians in the United States (Ernst et al., Chest
123:1693–1717, 2003). Indications include diagnosis of lung cancer and airway tumors, benign strictures, pulmonary infections,
and treatment of central airway obstruction, emphysema, and intraepithelial lesions such as carcinoma in-situ. Anesthesiologists,
cardiothoracic and trauma surgeons, otolaryngologists, and critical are physicians also perform this procedure as part of
difficult airway management, intubation or airway inspection and bronchial toilet. Compared to the expanding body of simulation-related
literature that is available in other procedural fields, however, the volume of published work relating to bronchoscopy is
scant. The purpose of this paper is to provide an overview of the available literature pertaining to the use of simulation
in bronchoscopy education, and to demonstrate how this limited yet valuable body of work lays a foundation for the future
use of simulator-based bronchoscopy training.
An erratum to this article can be found at 相似文献
993.
Muriel Lalanne Hania Khoury Alain Deroussent Nathalie Bosquet Henri Benech Pascal Clayette Patrick Couvreur Gilles Vassal Angelo Paci Karine Andrieux 《International journal of pharmaceutics》2009,379(2):235-243
Glycerolipidic prodrug is an interesting concept to enhance lymphatic absorption of polar drugs intended to oral delivery such as didanosine (ddI). In order to improve ddI bioavailability, two didanosine glycerolipidic prodrugs, the phosphorylated (ProddIP) and the non-phosphorylated derivatives (ProddINP) were synthesized to follow triglyceride metabolism. The biomimetism approach of these prodrugs has been studied in vitro at two steps. First, liposomal formulation of each prodrug was incubated with a lipolysis model based on pancreatin and analysed using liquid chromatography combined with tandem mass spectrometry (LC–MS/MS). These experiments evidenced that both didanosine prodrugs were recognized by the lipases; as expected, they were cleaved at both positions sn-1 and sn-3 of glycerol. ProddIP was metabolised twice more rapidly than ProddINP suggesting an implication of some phospholipases in ProddIP degradation. Secondly, the detection of dideoxyadenosine triphosphate (ddA-TP) into HIV-1 infected cells after their incubation with ProddINP loaded liposomes evidenced their ability to release ddI that could penetrate into the cells and be metabolised by intracellular kinases. These results confirmed that the synthesized glycerolipidic prodrugs of didanosine could be investigated for a biomimetic approach with final aiming of increasing the drug oral bioavailability by enhancing intestinal absorption. 相似文献
994.
Thao Tran Filip Claes Didier Verloo Henri De Greve Philippe Büscher 《Clinical and Vaccine Immunology : CVI》2009,16(7):999-1002
Current serological diagnosis of Trypanosoma evansi infection in camels is based on the native variable antigen type RoTat 1.2. The goal of this study was to develop a novel serological diagnostic test based on a nonvariable protein and freed from the use of rats or mice for its production. An enzyme-linked immunosorbent assay using a recombinant extracellular domain of invariant surface glycoprotein 75 (ELISA/rISG75) was developed and tested on a collection of 184 camel sera. The results were compared to those obtained from three established antibody detection tests based on variable surface glycoprotein RoTat 1.2: an ELISA for T. evansi (ELISA/T. evansi), a card agglutination test for trypanosomiasis (CATT/T. evansi), and an immune trypanolysis (TL) assay. The ELISA/rISG75 and the ELISA/T. evansi showed a sensitivity of 94.6% (95% confidence interval [CI], 87.8 to 98.2%, at 19% positivity cutoff value) and 98.9% (95% CI, 94.1 to 99.8, at 12% positivity cutoff value), respectively. The ELISA/rISG75 had 100% specificity (CI, 95.9 to 100%), while the ELISA/T. evansi showed 98.9% specificity (CI, 95.9 to 100%). The ELISA/rISG75 demonstrated an almost perfect agreement with the TL assay, the CATT/T. evansi, and the ELISA/T. evansi, with kappa scores of at least 0.94. The ELISA/rISG75, having a performance comparable to that of the gold standard (the TL assay) and being independent of antigenic variation, may become a new reference test for surra in camels. It opens avenues for the diagnosis of T. evansi infections in other hosts as well as for the development of a pan-Trypanozoon test for detection of Trypanosoma brucei brucei, T. b. gambiense, T. b. rhodesiense, T. evansi, and T. equiperdum.Trypanosoma evansi is the causative agent of surra in domestic animals such as camels, equines, cattle, buffaloes, small ruminants, and dogs. Wild animals such as capybaras can act as reservoir hosts. Although T. evansi is noninfective for healthy humans, a case of human infection by T. evansi in India in 2004 has been reported; however, this infection was due to a genetic mutation in the host''s APOL1 gene (20). Camels and horses are very sensitive to T. evansi, and death can occur within 3 months without treatment. Cattle and other ruminants infected by T. evansi suffer from immunosuppression, resulting in increased susceptibility to other diseases or vaccination failure (5, 17). T. evansi is mechanically transmitted by bloodsucking flies, such as Tabanidae and Stomoxys species. The disease occurs in Africa, Asia, and South and Central America and causes important economic losses (16).Control of surra still relies mainly on the observation of clinical signs and subsequent treatment of sick animals, which is inefficient and results in high morbidity and mortality of undiagnosed animals that in the meantime act as reservoirs. Definitive diagnosis of T. evansi infection is achieved by microscopic demonstration of the parasite, which method, however, suffers from limited sensitivity. The most sensitive parasite detection test is the mini-anion-exchange centrifugation method, but it is seldom used (4, 9). Indirect diagnosis is possible through detection of specific antibodies in the mammalian hosts. All currently available antibody detection tests, including an immune trypanolysis (TL) assay (21), an enzyme-linked immunosorbent assay for T. evansi (ELISA/T. evansi) (22), a card agglutination test for trypanosomiasis for T. evansi (CATT/T. evansi) (1), and a latex agglutination test for T. evansi (24), are based on the native variant surface glycoprotein (VSG) of the predominant variable antigen type (VAT) RoTat 1.2 of T. evansi. Production of these tests requires the mass culture of T. evansi homogeneously expressing RoTat 1.2 VSG in rats or mice. In addition, the results of all these serological tests may remain negative in animals infected with T. evansi type B in Kenya, as this type has been reported not to express the RoTat 1.2 VAT (13-15).On the cell surface of a bloodstream form trypanosome, among the VSGs and nonvariable surface proteins, there are an estimated 5 × 104 invariant surface glycoprotein (ISG75) molecules (28). The ISG75 gene family is present and transcribed in the bloodstream form of all species and subspecies of the Trypanozoon subgenus, including Trypanosoma brucei brucei, T. b. gambiense, T. b. rhodesiense, T. evansi, and T. equiperdum. This multicopy gene family consists of two main groups that share at least 75% similarity among their cDNA and genomic DNA sequences (19). Within each group, there is at least 92% similarity among the cDNA sequences. A putative ISG75, regardless of its belonging to group I or group II, has a conserved topology: a large N-terminal extracellular domain, a single α-helix transmembrane domain, and a small cytoplasmic domain at the C terminus (19, 27). Since ISG75 is not subject to antigenic variation, its corresponding antibodies circulate during the course of infections in mice (29), and its extracellular domain can be produced in Escherichia coli by a standardized protocol (18), it is considered a highly relevant antigen for diagnosis of Trypanozoon infections.The purpose of this study was to develop an antibody detection ELISA for T. evansi infection in camels by using recombinant ISG75 (rISG75). This ELISA/rISG75 was tested against a panel of 184 camel sera in parallel with the currently used serological diagnostic tests, including the TL assay, the CATT/T. evansi, and the ELISA/T. evansi. 相似文献
995.
Dianne J. Marais Henri Carrara Gita Ramjee Patti Kay Anna‐Lise Williamson 《Journal of medical virology》2009,81(2):203-210
The extent to which human immunodeficiency virus (HIV‐1) infection impacts on the ability to mount an effective immune response to HPV is unknown, but is relevant in planning HPV vaccine strategies for HIV‐1 infected individuals. This longitudinal study investigated changes shortly after HIV‐1 seroconversion on cervical HPV types and HPV‐16 antibody responses in serum and at the cervix of female sex workers. Typing of HPV DNA from cervical cells was done prior to HIV‐1 seroconversion and within 1 year and greater than 2 years after HIV‐1 seroconversion. Antibody determinations on serum and cervico‐vaginal rinse samples were by HPV‐16 virus‐like particle‐based, enzyme‐linked immunosorbent assay. Of 104 women tested, 40 (38.4%) became HIV‐1 seropositive (HIV‐positive) during the course of the study. Shortly after HIV‐1 seroconversion a significant increase in multiple (>1) HPV infection (OR 4.0, 95% CI 1.3–11.9) was observed compared with HIV‐1 seronegative (HIV‐negative) women and certain changes in HPV type infection. HIV‐1 seroconversion resulted in a reduced prevalence of serum HPV‐16 IgA and cervico‐vaginal IgA and IgG but an increased prevalence of serum HPV‐16 IgG. All HIV‐positive women had been exposed to HPV‐16 as all displayed serum HPV‐16 IgG. Serum HPV‐16 responses were maintained at a high magnitude in the presence of HPV‐16 infection irrespective of HIV infection, but decreased in the absence of HPV‐16 infection. In conclusion, HIV‐1 seroconversion in sex workers rapidly increased cervical HPV infection and caused a reduced ability to produce cervical HPV‐16 antibodies but a continued ability to generate serum IgG antibodies. J. Med. Virol. 81:203–210, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
996.
Batard T Hrabina A Bi XZ Chabre H Lemoine P Couret MN Faccenda D Villet B Harzic P André F Goh SY André C Chew FT Moingeon P 《International archives of allergy and immunology》2006,140(4):295-305
BACKGROUND: House dust mites (HDM) such as Dermatophagoides pteronyssinus and Dermatophagoides farinae represent a major cause of type 1 allergies worldwide. Hence large quantities of well-characterized HDM extracts are needed to prepare pharmaceutical-grade allergy vaccines. To this aim, the present study was undertaken to define optimal conditions for large-scale cultures. METHODS: D. pteronyssinus and D. farinae were grown on different media combining various proportions of wheat germ, yeast and synthetic amino acids (the latter resembling the composition of the human stratum corneum). Extracts thus obtained were analyzed for their total allergenic activity, as well as major allergen and protein contents, using immunosorbent assays, HPLC, immunoblotting, two-dimensional electrophoresis and peptide mass fingerprinting. RESULTS: An optimal culture medium (Stalmite APF) based on wheat germ, yeast and amino acids in defined proportion (42, 42 and 15% w/w, respectively) was selected to grow various HDM species with high yields. A detailed proteomic analysis revealed that D. pteronyssinus extracts generated under such conditions did not contain allergens originating from culture medium components and that major prevalent HDM allergens (i.e. groups 1, 2, 7, 10, 13 and 20) are found among the most abundant proteins in the D. pteronyssinus extract. Semiquantitative dot-blot assays confirmed the presence of Der p 3-10 as well as Der p 13 and 14 allergens within the extracts. CONCLUSIONS: We developed a well-defined medium allowing to grow various HDM species at an industrial scale in a highly reproducible manner. Extracts from mites produced under such pharmaceutical conditions contain all the relevant allergens for desensitization purposes and in vivo diagnosis. 相似文献
997.
Clonal distribution and differential occurrence of the enterotoxin gene cluster, egc, in carriage- versus bacteremia-associated isolates of Staphylococcus aureus
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van Belkum A Melles DC Snijders SV van Leeuwen WB Wertheim HF Nouwen JL Verbrugh HA Etienne J 《Journal of clinical microbiology》2006,44(4):1555-1557
The Staphylococcus aureus enterotoxin gene cluster, egc, was detected in isolates from healthy individuals and in those from patients with bacteremia. The egc genes cooccur and are slightly enriched in strains from healthy carriers (present in 63.7% of carriage-associated isolates versus 52.9% of invasive isolates; P = 0.03). Multilocus sequence typing revealed that successful staphylococcal clones usually harbor the egc locus. 相似文献
998.
Harf-Monteil C Granello C Le Brun C Monteil H Riegel P 《Journal of clinical microbiology》2006,44(6):2240-2241
We evaluated the incidence of Streptococcus pseudopneumoniae in clinical isolates by phenotypic methods and DNA-DNA hybridization. The pathogenic role of this organism was investigated with the mouse peritonitis/sepsis model. Our results show a low incidence (1/120 pneumococcal isolates) and a potential pathogenic effect for S. pseudopneumoniae. 相似文献
999.
Promoter dependence of transgene expression by lentivirus-transduced human blood-derived endothelial progenitor cells 总被引:1,自引:0,他引:1
Liu JW Pernod G Dunoyer-Geindre S Fish RJ Yang H Bounameaux H Kruithof EK 《Stem cells (Dayton, Ohio)》2006,24(1):199-208
Peripheral blood- derived endothelial progenitor cells (EPCs) have considerable potential for the autologous therapy of vascular lesions or ischemic tissues. By introducing stable genetic modifications into these cells, this potential might be further enhanced. We investigated to what extent transgene expression can be controlled by using different transgene promoters. This was investigated in early- or late-outgrowth human EPCs obtained by culturing blood mononuclear cells for 1 or 4 weeks on type 1 collagen in medium containing endothelial growth supplements. A large fraction of these cells were stably transduced using lentiviral vectors for expression of the enhanced green fluorescent protein (EGFP). Transgene expression in vitro or in vivo after injection into nude mice was highest when under the control of the cytomegalovirus (CMV) promoter, intermediate with the EF1alpha promoter, and lowest with the phosphoglycerate kinase promoter. When blood mononuclear cells were cultured for 1 week in the absence of endothelial growth supplements, CMV promoter- driven expression of EGFP was two orders of magnitude lower than in similarly transduced EPCs. Our results show that lentiviral vectors are useful tools for the stable introduction of exogenous genes into EPCs and for their expression at desired levels using the appropriate gene promoter. 相似文献
1000.
Bajos N Lamarche-Vadel A Gilbert F Ferrand M;COCON Group Moreau C Bouyer J Ducot B Hassoun D Goulard H Job-Spira N Kaminski M Lelong N Leridon H Razafindratsima N Rossier C Warszawski J 《Human reproduction (Oxford, England)》2006,21(11):2862-2867
BACKGROUND: Despite the widespread use of highly effective contraception in France, the incidence of abortion is high. A retrospective population-based cohort study was designed to analyse women's contraceptive history. METHOD: We compared the contraceptive use of 163 women, whose last pregnancy ended in abortion, 6 months before, at the time of, 1 month and 6 months after the event with that of 1787 women who had never had an abortion. RESULTS: A total of 46% of women who experienced an abortion used a highly effective form of contraception 6 months before the event (versus 76% among women who had never had an abortion, P < 0.001). This proportion dropped to 33% at the time of the abortion and increased to 71%, 1 month after. In addition, 50% of women who had an abortion had changed their contraceptive method in the 6 months before the event (compared with 16% in the 6 months before the interview in women who had not had an abortion, P < 0.001). Women with socially deprived backgrounds were less likely to use a highly effective contraception after an abortion. CONCLUSIONS: Abortion is a good opportunity for intervention, but especially so for socially disadvantaged women. It is essential to draw the attention of prescribers and women to the higher risk of contraceptive failure at the start of use of a method. 相似文献