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61.
Houyem Mansouri Ines Zemni Leila Achouri Najet Mahjoub Mohamed Ali Ayedi Ines Ben Safta Tarek Ben Dhiab Riadh Chargui Khaled Rahal 《Reports of Practical Oncology and Radiotherapy》2021,26(2):266
BackgroundThe management of gastric adenocarcinoma is essentially based on surgery followed by adjuvant treatment. Adjuvant chemotherapy (CT) as well as chemoradiotherapy (CTRT) have proven their effectiveness in survival outcomes compared to surgery alone. However, there is little data comparing the two adjuvant approaches. This study aimed to compare the prognosis and survival outcomes of patients with gastric adenocarcinoma operated and treated by adjuvant radio-chemotherapy or chemotherapyMaterials and methodsWe retrospectively evaluated 80 patients with locally advanced gastric cancer (LGC) who received adjuvant treatment. We compared survival outcomes and patterns of recurrence of 53 patients treated by CTRT and those of 27 patients treated by CT.ResultsAfter a median follow-up of 38.48 months, CTRT resulted in a significant improvement of the 5-year PFS (60.9% vs. 36%, p = 0.03) and the 5-year OS (55.9% vs. 33%, p = 0.015) compared to adjuvant CT. The 5-year OS was significantly increased by adjuvant CTRT (p = 0.046) in patients with lymph node metastasis, and particularly those with advanced pN stage (p = 0.0078) and high lymph node ratio (LNR) exceeding 25% (p = 0.012). Also, there was a significant improvement of the PFS of patients classified pN2–N3 (p = 0.022) with a high LNR (p = 0.018). CTRT was also associated with improved OS and PFS in patients with lymphovascular and perineural invasion (LVI and PNI) compared to chemotherapy.ConclusionThere is a particular survival benefit of adding radiotherapy to chemotherapy in patients with selected criteria such as lymph node involvement, high LNR LVI, and PNI. 相似文献
62.
Zhang Y Cuevas S Asico LD Escano C Yang Y Pascua AM Wang X Jones JE Grandy D Eisner G Jose PA Armando I 《PloS one》2012,7(6):e38745
Renal dopamine receptors participate in the regulation of blood pressure. Genetic factors, including polymorphisms of the dopamine D(2) receptor gene (DRD2) are associated with essential hypertension, but the mechanisms of their contribution are incompletely understood. Mice lacking Drd2 (D(2)-/-) have elevated blood pressure, increased renal expression of inflammatory factors, and renal injury. We tested the hypothesis that decreased dopamine D(2) receptor (D(2)R) function increases vulnerability to renal inflammation independently of blood pressure, is an immediate cause of renal injury, and contributes to the subsequent development of hypertension. In D(2)-/- mice, treatment with apocynin normalized blood pressure and decreased oxidative stress, but did not affect the expression of inflammatory factors. In mouse RPTCs Drd2 silencing increased the expression of TNFα and MCP-1, while treatment with a D(2)R agonist abolished the angiotensin II-induced increase in TNF-α and MCP-1. In uni-nephrectomized wild-type mice, selective Drd2 silencing by subcapsular infusion of Drd2 siRNA into the remaining kidney produced the same increase in renal cytokines/chemokines that occurs after Drd2 deletion, increased the expression of markers of renal injury, and increased blood pressure. Moreover, in mice with two intact kidneys, short-term Drd2 silencing in one kidney, leaving the other kidney undisturbed, induced inflammatory factors and markers of renal injury in the treated kidney without increasing blood pressure. Our results demonstrate that the impact of decreased D(2)R function on renal inflammation is a primary effect, not necessarily associated with enhanced oxidant activity, or blood pressure; renal damage is the cause, not the result, of hypertension. Deficient renal D(2)R function may be of clinical relevance since common polymorphisms of the human DRD2 gene result in decreased D(2)R expression and function. 相似文献
63.
64.
Alvarez I Bengochea M Toledo R Carretto E Hidalgo PC 《Human biology; an international record of research》2006,78(4):513-525
HLA class I antigens were determined for 959 unrelated Uruguayans. The predominant HLA alleles were A2, Cw4, and B35, and the most frequently observed two-loci haplotypes were A2-B44 and B35-Cw4. The most frequent three-loci HLA haplotype was A2-Cw5-B44. We compared the Uruguayan sample with similar data from other populations. 相似文献
65.
The WW domain protein PRO40 is required for fungal fertility and associates with Woronin bodies 下载免费PDF全文
Engh I Würtz C Witzel-Schlömp K Zhang HY Hoff B Nowrousian M Rottensteiner H Kück U 《Eukaryotic cell》2007,6(5):831-843
Fruiting body formation in ascomycetes is a highly complex process that is under polygenic control and is a fundamental part of the fungal sexual life cycle. However, the molecular determinants regulating this cellular process are largely unknown. Here we show that the sterile pro40 mutant is defective in a 120-kDa WW domain protein that plays a pivotal role in fruiting body maturation of the homothallic ascomycete Sordaria macrospora. Although WW domains occur in many eukaryotic proteins, homologs of PRO40 are present only in filamentous ascomycetes. Complementation analysis with different pro40 mutant strains, using full-sized or truncated versions of the wild-type pro40 gene, revealed that the C terminus of PRO40 is crucial for restoring the fertile phenotype. Using differential centrifugation and protease protection assays, we determined that a PRO40-FLAG fusion protein is located within organelles. Further microscopic investigations of fusion proteins with DsRed or green fluorescent protein polypeptides showed a colocalization of PRO40 with HEX-1, a Woronin body-specific protein. However, the integrity of Woronin bodies is not affected in mutant strains of S. macrospora and Neurospora crassa, as shown by fluorescence microscopy, sedimentation, and immunoblot analyses. We discuss the function of PRO40 in fruiting body formation. 相似文献
66.
Standley SM Mende I Goh SL Kwon YJ Beaudette TT Engleman EG Fréchet JM 《Bioconjugate chemistry》2007,18(1):77-83
The development of multicomponent biotherapeutic carriers is an important challenge in the field of drug delivery, particularly in the area of protein-based vaccines. While the delivery of protein antigens to antigen presenting cells (APCs) is crucial for this type of vaccination, the incorporation of additional adjuvants may be just as important in order to generate more potent immune responses. This article presents the synthesis and biological evaluation of carrier particles that both deliver a protein payload to APCs and display receptor ligands for the enhancement of APC immunostimulation. Particles displaying CpG oligonucleotide ligands for Toll-like receptor 9 were synthesized. The addition of CpG DNA to the particles led to a 45-fold increase in the secretion of interleukin-12, a cytokine that aids in T-cell activation, and a significant increase in the expression of costimulatory molecules by APCs. Moreover, vaccination with particles containing both ovalbumin (OVA) and CpG DNA induced a superior OVA-specific CD8 T-cell response in vivo, as measured by increased OVA-specific CD8 T-cell proliferation, secretion of the proinflammatory cytokine IFN-gamma, and the induction of OVA-specific cytotoxicity. 相似文献
67.
Epidermal langerhans cells are dispensable for humoral and cell-mediated immunity elicited by gene gun immunization 总被引:2,自引:0,他引:2
Stoecklinger A Grieshuber I Scheiblhofer S Weiss R Ritter U Kissenpfennig A Malissen B Romani N Koch F Ferreira F Thalhamer J Hammerl P 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(2):886-893
Gene gun immunization, i.e., bombardment of skin with DNA-coated particles, is an efficient method for the administration of DNA vaccines. Direct transfection of APC or cross-presentation of exogenous Ag acquired from transfected nonimmune cells enables MHC-I-restricted activation of CD8(+) T cells. Additionally, MHC-II-restricted presentation of exogenous Ag activates CD4(+) Th cells. Being the principal APC in the epidermis, Langerhans cells (LC) seem ideal candidates to accomplish these functions. However, the dependence on LC of gene gun-induced immune reactions has not yet been demonstrated directly. This was primarily hampered by difficulties to discriminate the contributions of LC from those of other dermal dendritic cells. To address this problem, we have used Langerin-diphtheria toxin receptor knockin mice that allow for selective inducible ablation of LC. LC deficiency, even over the entire duration of experiments, did not affect any of the gene gun-induced immune functions examined, including proliferation of CD4(+) and CD8(+) T cells, IFN-gamma secretion by spleen cells, Ab production, CTL activity, and development of protective antitumor immunity. Together, our data show that gene gun immunization is capable of inducing humoral and cell-mediated immune reactions independently of LC. 相似文献
68.
Ben Sghaier M Chraief I Skandrani I Bouhlel I Boubaker J Kilani S Neffati A Mahmoud A Hammami M Chekir-Ghedira L Ghedira K 《化学与生物多样性》2007,4(7):1480-1486
The phytochemical composition of the essential oil of Teucrium ramosissimum (aerial parts), harvested in a mountainous region of Tunisia, was analyzed. A total of 68 compounds, accounting for 99.44% of the essential oil, were identified by GC and GC/MS. The major compounds were beta-eudesmol (61; 44.52%), caryophyllene oxide (56; 9.35%), alpha-thujene (1; 5.51%), sabinene (4; 4.71%), and T-cadinol (59; 3.9%). The essential oil, which is being used in Tunisian folk medicine against infectious diseases, was tested for its antimicrobial properties against five different bacteria, and found to have weak to moderate activity, with minimal-inhibitory-concentration (MIC) and minimal-bactericidal-concentration (MBC) values in the range 0.24-0.36 and 1.3-2.9 mg/ml, resp. 相似文献
69.
Saba H Batinic-Haberle I Munusamy S Mitchell T Lichti C Megyesi J MacMillan-Crow LA 《Free radical biology & medicine》2007,42(10):1571-1578
Renal ischemia/reperfusion (I/R) injury often occurs as a result of vascular surgery, organ procurement, or transplantation. We previously showed that renal I/R results in ATP depletion, oxidant production, and manganese superoxide dismutase (MnSOD) inactivation. There have been several reports that overexpression of MnSOD protects tissues/organs from I/R-related damage, thus a loss of MnSOD activity during I/R likely contributes to tissue injury. The present study examined the therapeutic benefit of a catalytic antioxidant, Mn(III) meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin (MnTnHex-2-PyP(5+)), using the rat renal I/R model. This was the first study to examine the effects of MnTnHex-2-PyP(5+) in an animal model of oxidative stress injury. Our results showed that porphyrin pretreatment of rats for 24 h protected against ATP depletion, MnSOD inactivation, nitrotyrosine formation, and renal dysfunction. The dose (50 microg/kg) used in this study is lower than doses of various types of antioxidants commonly used in animal models of oxidative stress injuries. In addition, using novel proteomic techniques, we identified the ATP synthase-beta subunit as a key protein induced by MnTnHex-2-PyP(5+) treatment alone and complex V (ATP synthase) as a target of injury during renal I/R. These results showed that MnTnHex-2-PyP(5+) protected against renal I/R injury via induction of key mitochondrial proteins that may be capable of blunting oxidative injury. 相似文献
70.
Rima Ezzeddine Anwar Al-Banaw Artak Tovmasyan James D. Craik Ines Batinic-Haberle Ludmil T. Benov 《The Journal of biological chemistry》2013,288(51):36579-36588
Tetra-cationic Zn(II) meso-tetrakis(N-alkylpyridinium-2 (or -3 or -4)-yl)porphyrins (ZnPs) with progressively increased lipophilicity were synthesized to investigate how the tri-dimensional shape and lipophilicity of the photosensitizer (PS) affect cellular uptake, subcellular distribution, and photodynamic efficacy. The effect of the tri-dimensional shape of the molecule was studied by shifting the N-alkyl substituent attached to the pyridyl nitrogen from ortho to meta and para positions. Progressive increase of lipophilicity from shorter hydrophilic (methyl) to longer amphiphilic (hexyl) alkyl chains increased the phototoxicity of the ZnP PSs. PS efficacy was also increased for all derivatives when the alkyl substituents were shifted from ortho to meta, and from meta to para positions. Both cellular uptake and subcellular distribution of the PSs were affected by the lipophilicity and the position of the alkyl chains on the periphery of the porphyrin ring. Whereas the hydrophilic ZnPs demonstrated mostly lysosomal distribution, the amphiphilic hexyl derivatives were associated with mitochondria, endoplasmic reticulum, and plasma membrane. A comparison of hexyl isomers revealed that cellular uptake and partition into membranes followed the order para > meta > ortho. Varying the position and length of the alkyl substituents affects (i) the exposure of cationic charges for electrostatic interactions with anionic biomolecules and (ii) the lipophilicity of the molecule. The charge, lipophilicity, and the tri-dimensional shape of the PS are the major factors that determine cellular uptake, subcellular distribution, and as a consequence, the phototoxicity of the PSs. 相似文献