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2.
Cancers (Basel) ; 14(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35159111

RESUMO

PURPOSE: We set out to demonstrate the benefit of using dose-intense cisplatin-based neoadjuvant chemotherapy in terms of overall survival and progression-free survival. METHODS: We searched through MEDLINE and Cochrane Library databases up to May 2021 to identify randomized clinical trials comparing the benefit of using cisplatin-based neoadjuvant chemotherapy followed by local treatment with local treatment alone for the treatment of locally advanced cervical cancer. The PRISMA statement was applied. RESULTS: Twenty-two randomized clinical trials were retrieved between 1991 and 2019, corresponding to 3632 women with FIGO stages IB2-IVA cervical cancer. More than 50% of the randomized clinical trials were assessed as having a low risk of bias. There was no benefit of neoadjuvant chemotherapy on overall survival, but there was significant heterogeneity across studies (I2 = 45%, p = 0.01). In contrast, dose-intense cisplatin at over 72.5 mg/m2/3 weeks was significantly associated with increased overall survival (RR = 0.87, p < 0.05) with no heterogeneity across the pooled studies (I2 = 36%, p = 0.11). The survival benefit was even greater when cisplatin was administered at a dose over 105 mg/m2/3 weeks (RR = 0.79, p < 0.05). CONCLUSION: Even though radiotherapy combined with weekly cisplatin-based chemotherapy remains standard of care for the treatment of locally advanced cervical cancer, our meta-analysis makes it possible to consider the use of dose-intense cisplatin-based neoadjuvant chemotherapy when local treatment is suboptimal and opens perspectives for designing new clinical trials in this setting. Neoadjuvant chemotherapy could be proposed when surgery is local treatment instead of standard chemoradiotherapy for the treatment of locally advanced cervical cancer.

3.
Environ Sci Pollut Res Int ; 29(26): 39777-39789, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35113371

RESUMO

Plasticizers such as di(2-ethylhexyl) phthalate (DEHP) and tris (2-butoxyethyl) phosphate (TBOEP) are manufactured chemicals produced in high volumes. These chemicals are frequently detected in the aquatic environment and cause toxic effects on organisms. In this study, we assessed the chronic impacts of DEHP and TBOEP, respectively, at the concentration of 100 µg L-1 dissolved in the artificial medium (M4/4) and Mekong River water on life history traits of a tropical micro-crustacean, Ceriodaphnia cornuta, for 14 days. DEHP and TBOEP substantially reduced the survival of C. cornuta. In M4/4 medium, both plasticizers strongly enhanced reproduction but did not influence the growth of C. cornuta. Mekong River water, plasticizers-exposed C. cornuta produced less neonates than those in the control. The detrimental impacts of DEHP and TBOEP on the fitness of C. cornuta were much stronger in natural river water than in M4/4. Our results suggest that plasticizers can cause adverse effects on tropical freshwater cladocerans, particularly in natural water. These results are of a deep concern, as national and international regulatory guidelines which are based on ecotoxicological tests using standard media may not fully capture these effects.


Assuntos
Cladocera , Dietilexilftalato , Animais , Dietilexilftalato/toxicidade , Humanos , Recém-Nascido , Organofosfatos , Fosfatos , Ácidos Ftálicos , Plastificantes/análise , Plastificantes/toxicidade , Rios , Água
4.
Eur Urol ; 81(4): 349-361, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34991918

RESUMO

CONTEXT: Although antiangiogenic treatments and immunotherapies have significantly improved the prognosis of metastatic renal cell carcinoma (RCC), many patients will develop resistance, leading to treatment failure. Genetic tumor heterogeneity is a major cause of this resistance. OBJECTIVE: To perform a meta-analysis of genomic data for clear-cell RCC obtained from primary tumors and metastases to assess the prevalence of gene mutations and copy number alterations (CNAs). EVIDENCE ACQUISITION: Articles were selected from Medline and Embase libraries using the search algorithm ("Kidney Neoplasms"[Mesh] OR "Renal Cell Carcinoma") AND ("Genomics"[Mesh] OR "Mutation") from January 1999 to February 2021. A critical review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. Ninety-three publications were selected for inclusion in this meta-analysis. EVIDENCE SYNTHESIS: Our meta-analysis included a total 14 696 patients, 14 299 primary tumor samples, and 969 metastatic samples. We evaluated the overall and subgroup prevalence of gene mutations and CNAs, including comparisons between primary tumors and metastases. In particular, for metastases we observed that the mutation prevalence was significantly more marked for ten genes compared to primary tumors, with no or little heterogeneity across studies. The VHL mutation prevalence increased significantly from 64% in primary tumors to 75% in metastases (p < 0.001). There was a significant increase in CNA prevalence from primary tumors to metastases for chromosomes 1p36.11, 9p21.3, and 18 in terms of losses, and for chromosomes 1q21.3, 7q36.3, 8q, and 20q11.21 in terms of gains. CDKN2A, also called p16 and involved in cell-cycle progression, is located at the 9p21.3 locus and was lost in 76% of metastatic samples. ASXL1, located on 20p11.21 and amplified in 50% of metastatic RCCs compared to 21% of primary tumors (p < 0.001), is closely linked to BAP1 function. CONCLUSIONS: Our results underline the added value of preferential biopsies on RCC metastases to fully explore the biology of metastatic disease for therapeutic purposes. PATIENT SUMMARY: We reviewed the literature on genetic mutations in primary tumors and metastatic lesions in kidney cancer. Our pooled results for all the relevant studies show a higher level of mutations in metastases than in primary tumors. This highlights the importance of taking biopsies of metastases to analyze genetic mutations and potentially guide selection of the most suitable treatment strategy.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/patologia , Variações do Número de Cópias de DNA , Feminino , Genômica , Humanos , Neoplasias Renais/patologia , Masculino , Prognóstico
5.
J Funct Biomater ; 11(2)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32370007

RESUMO

A series of biocompatible high-porosity (up to 72.4%) TiZr-based porous bulk metallic glass (BMG) scaffolds were successfully fabricated by hot pressing a mixture of toxic element-free TiZr-based BMG powder and an Al particle space holder. The morphology of the fabricated scaffolds was similar to that of human bones, with pore sizes ranging from 75 to 250 µm. X-ray diffraction patterns and transmission electron microscopy images indicated that the amorphous structure of the TiZr-based BMG scaffolds remained in the amorphous state after hot pressing. Noncytotoxicity and extracellular calcium deposition of the TiZr-based BMG scaffolds at porosities of 32.8%, 48.8%, and 64.0% were examined by using the direct contact method. The results showed that the BMG scaffolds possess high cell viability and extracellular calcium deposition with average cell survival and deposition rates of approximately 170.1% and 130.9%, respectively. In addition, the resulting TiZr-based BMG scaffolds exhibited a considerable reduction in Young's moduli from 56.4 to 2.3 GPa, compressive strength from 979 to 19 MPa, and bending strength from 157 MPa to 49 MPa when the porosity was gradually increased from 2.0% to 72.4%. Based on the aforementioned specific characteristics, TiZr-based BMG scaffolds can be considered as potential candidates for biomedical applications in the human body.

6.
ChemMedChem ; 14(15): 1431-1443, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31264794

RESUMO

Derivatives of 5'-aminoadenosine containing methyl carboxylate, methyl phosphonate, gem-bisphosphonate, bis(methylphosphonate), and α-carboxylmethylphosphonate or phosphonoacetate moieties were synthesized from key intermediate 5'-aminonucleoside. These nucleotide analogues were envisaged as 5'-mono- or diphosphate nucleoside mimics. All compounds were evaluated for CD73 inhibition in a cell-based assay (MDA-MB-231) and toward the purified recombinant protein. Most of them failed to reach significant inhibition of AMP hydrolysis by CD73 at 100 µm. Among the new compounds, the most interesting candidates, 5 (5'-deoxy-5'-N-phosphonomethyladenosine) and 7 (5'-deoxy-5'-N-(ethoxyphosphorylacetate)adenosine), inhibited recombinant CD73 by 36 and 46 % and cellular CD73 by 61 and 45 % at 100 µm, respectively. Molecular modeling partially explains this lack of activity, as the initially predicted docking scores had been encouraging, especially for compound 9.


Assuntos
5'-Nucleotidase/antagonistas & inibidores , Adenosina/análogos & derivados , Adenosina/síntese química , Antineoplásicos/síntese química , Inibidores Enzimáticos/síntese química , Adenosina/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Proteínas Ligadas por GPI/antagonistas & inibidores , Humanos , Modelos Moleculares , Estrutura Molecular , Organofosfonatos/química , Compostos Organofosforados/química , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/química , Relação Estrutura-Atividade
7.
Beilstein J Org Chem ; 12: 1476-86, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27559400

RESUMO

A series of seventeen ß-hydroxyphosphonate ribonucleoside analogues containing 4-substituted-1,2,3-triazoles was synthesized and fully characterized. Such compounds were designed as potential inhibitors of the cytosolic 5'-nucleotidase II (cN-II), an enzyme involved in the regulation of purine nucleotide pools. NMR and molecular modelling studies showed that a few derivatives adopted similar structural features to IMP or GMP. Five derivatives were identified as modest inhibitors with 53 to 64% of cN-II inhibition at 1 mM.

8.
Beilstein J Org Chem ; 3: 47, 2007 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-18078507

RESUMO

Under carefully controlled conditions, the triethylborane-air combination proves to be an efficient radical initiator that allows intermolecular radical additions of S-2-oxoalkyl-thionocarbonates (S-xanthates) to olefins. Depending on both the structures of the xanthate and the olefin, the addition process can be achieved at room temperature or slightly higher.

9.
Beilstein J Org Chem ; 3: 45, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18076754

RESUMO

A new, mild, and environment friendly process for the reduction of S-alkyl-thionocarbonates, iodides and related compounds to the corresponding hydrocarbons at room temperature with good to excellent yields is described. This method uses a trialkylborane in excess (Et3B or Bu3B) and air.

10.
Beilstein J Org Chem ; 3: 46, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18076755

RESUMO

Experiments conducted with deuterated compounds demonstrated that during the reduction of S-alkylxanthates with triethylborane, the hydrogen atom transferred has several competing origins. Hydrogen abstraction from water (or an alcohol) is the most favourable route.

11.
Org Lett ; 5(10): 1645-8, 2003 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12735742

RESUMO

[reaction: see text] Reductive cleavage of the carbon-sulfur bond present in S-alkyl-thionocarbonates (xanthates) was achieved by high-yielding, tin-free radical reactions based on phosphorus reagents. The combination hypophosphorous acid/triethylamine/AIBN led to fast, efficient, and smooth formation of the alkane. Reduction with diethyl phosphite was sufficiently slow to permit sequential intermolecular addition of a 2-oxoalkyl xanthate onto an olefin followed by cleavage of the newly formed carbon-sulfur bond.

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