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81.
Dolores Caballero Jose A García-Marco Rodrigo Martino Victoria Mateos José M Ribera José Sarrá Angel León Guillermo Sanz Javier de la Serna Rafael Cabrera Marcos González Jorge Sierra Jesús San Miguel 《Clinical cancer research》2005,11(21):7757-7763
PURPOSE: To evaluate the efficacy of reduced intensity conditioning (RIC) allogeneic transplant in 30 patients with poor-prognosis chronic lymphocytic leukemia (CLL) and/or high-risk molecular/cytogenetic characteristics. EXPERIMENTAL DESIGN: Eighty-three percent of patients had active disease at the moment of transplant. That is, 14 of the 23 patients analyzed (60%) had unmutated immunoglobulin variable heavy-chain gene (IgV(H)) status; 8 of 25 patients (32%) had 11q-, with four of them also displaying unmutated IgV(H); and six (24%) had 17p- (five were also unmutated). RESULTS: After a median follow-up of 47.3 months, all 22 patients alive are disease free; overall survival and event-free survival (EFS) at 6 years were 70% and 72%, respectively. According to molecular/cytogenetic characteristics, overall survival and EFS for unmutated CLL and/or with 11q- aberration (n = 13) were 90% and 92%, respectively, not significantly different to those with normal in situ hybridization, 13q- and +12, or mutated CLL (n = 7). All six patients with 17p deletion were transplanted with active disease, including three with refractory disease; all except one reached complete remission after the transplant and two are alive and disease free. Nonrelapse mortality (NRM) was 20%; more than two lines before transplant is an independent prognostic factor for NRM (P = 0,02), EFS (P = 0.02), and overall survival (P = 0.01). Patients older than 55 years have a higher risk of NRM (hazard ratio, 12.8; 95% confidence interval, 1.5-111). Minimal residual disease was monitored by multiparametric flow cytometry in 21 patients. Clearance of CD79/CD5/CD19/CD23 cells in bone marrow was achieved in 68% and 94% of the patients at days 100 and 360, respectively. CONCLUSION: According to these results, RIC allogeneic transplant could overcome the adverse prognosis of patients with unmutated CLL as well as those with 11q- or 17p-. 相似文献
82.
Rafael Manon Anne O'Neill Jonathan Knisely Maria Werner-Wasik Hillard M Lazarus Henry Wagner Mark Gilbert Minesh Mehta 《Journal of clinical oncology》2005,23(34):8870-8876
PURPOSE: Long-term brain metastases survivors are at risk for neurologic morbidity after whole-brain radiotherapy (WBRT). Retrospective radiosurgery (RS) reports found no survival difference when compared with WBRT. Before RS alone was evaluated with delayed WBRT in a phase III trial, the feasibility of RS alone was tested prospectively. PATIENTS AND METHODS: Patients with renal cell carcinoma, melanoma, or sarcoma; one to three brain metastases; and performance status of 0 to 2 were enrolled. Exclusion criteria were leptomeningeal disease; metastases in medulla, pons, or midbrain; or liver metastases. On the basis of tumor size, patients received 24, 18, or 15 Gy RS. At recurrence, management was discretionary. The primary end point was 3- and 6-month intracranial progression. RESULTS: Between July 1998 and August 2003, 36 patients were accrued; 31 were eligible. Median follow-up was 32.7 months and the median survival was 8.3 months (95% CI, 7.4 to 12.2). Three- and 6-month intracranial failure with RS alone was 25.8% and 48.3%. Failure within and outside the RS volume, when in-field and distant intracranial failures were scored independently, was 19.3% and 16.2% (3 months) and 32.2% and 32.2% (6 months), respectively. Approximately 38% of patients experienced death attributable to neurologic cause. There were three grade 3 toxicities related to RS. CONCLUSION: Intracranial failure rates without WBRT were 25.8% and 48.3% at 3 and 6 months, respectively. Delaying WBRT may be appropriate for some subgroups of patients with radioresistant tumors, but routine avoidance of WBRT should be approached judiciously. 相似文献
83.
Veridiana M Rodrigues Silvana Marcussi Rafael S Cambraia Ana L de Araújo Natael R Malta-Neto Amélia Hamaguchi Eloísa A V Ferro Maria I Homsi-Brandeburgo José R Giglio Andreimar M Soares 《Toxicon》2004,44(3):305-314
Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects. 相似文献
84.
Dbora Aparecida Oliveira Modena Rafael de Castro Ferreira Patricia Meyer Froes Katya Cristina Rocha 《The Journal of clinical and aesthetic dermatology》2022,15(5):65
BackgroundKnown in the past for its toxic aspect as the main urban pollutant, in the last few decades, ozone has been gaining greater visibility for its possible antimicrobial, antiviral, and antioxidant effects when used in human dermatological pathologies. Despite the reports of clinical benefits, the standard dosage for clinical efficacy and safety are yet not clear, nor are its means of application and its true acting mechanism.ObjectiveWe conducted a review to determine the efficacy and safety of ozone therapy for a variety of dermatological conditions.MethodsWe considered clinical trials (both randomized and non-randomized) published between December 2020 and March 2021 as long as they provided some PICO information, i.e., population (P), intervention (I), and study design. The skin dermatological conditions researched were: acne, dermatitis, psoriasis, systemic sclerosis, herpes, aging, ulcers, and skin scarring.ResultsA total of 326 articles were identified and 150 remained after duplicates were removed. After titles, abstracts and full articles were read, 17 articles were included in the systematic review (with 643 patients). ConclusionOzone therapy seems promising for some dermatological conditions; however, the articles included in this review had methodological limitations and did not sufficiently demonstrate sound evidence for safe therapy. Therefore, more studies with better methodological standards and longer-term assessments of side effects should be conducted to achieve better standards and safety in ozone therapy for dermatological conditions. 相似文献
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88.
Camilla Rodrigues de Almeida Ribeiro Katrini Guidolini Martinelli Vinícius da Motta de Mello Natlia Spitz Oscar Rafael Carmo Araújo Lia Laura Lewis-Ximenez Natalia Motta Araujo Vanessa Salete de Paula 《Viruses》2022,14(7)
Several hepatitis B virus (HBV)-related factors, including the viral load, genotype, and genomic mutations, have been linked to the development of liver diseases. Therefore, in this study we aimed to investigate the influence of HBV genetic variability during acute and chronic infection phases. A real-time nested PCR was used to detect HBV DNA in all samples (acute, n = 22; chronic, n = 49). All samples were sequenced for phylogenetic and mutation analyses. Genotype A, sub-genotype A1, was the most common genotype in the study population. A total of 190 mutations were found in the pre-S/S gene area and the acute profile revealed a greater number of nucleotide mutations (p < 0.05). However, both profiles contained nucleotide mutations linked to immune escape and an increased risk of hepatocellular carcinomas (acute, A7T; chronic, A7Q). Furthermore, 17 amino acid substitutions were identified in the viral polymerase region, including the drug resistance mutations lamivudine and entecavir (rtL180M), with statistically significant differences between the mutant and wild type strains. Owing to the natural occurrence of these mutations, it is important to screen for resistance mutations before beginning therapy. 相似文献
89.
Panagiotis M. Angelopoulos Nikolaos Rafael Vrithias Zacharias Viskadourakis Petros Tsakiridis Konstantinos C. Vasilopoulos Antonis Peppas Georgios Asimakopoulos Anastasia V. Spyrou Michael A. Karakassides Maria Taxiarchou George Kenanakis 《Materials》2022,15(14)
The use of amorphous microspheres as filler in composites is promising due to their light weight, low cost, incombustibility, and the ability to alter relevant properties of the final composite. Contrary to glass spheres, perlite microspheres are much cheaper and can be tailor-made to facilitate purpose-oriented alteration of the final composite. We report the use of perlite microspheres for the preparation of: (1) composites, through a compression molding (hot pressing) technique; and (2) composite filaments, in a single screw extruder, as well as their use for sample printing through Fused Deposition Modeling (FDM). Proper characterization of the produced composites allows for their evaluation in terms of physical, thermal, and mechanical properties and with regards to the manufacturing technique, the filler fraction, and size. Composite samples of acceptable quality in terms of filler survival and dispersion as well as mechanical properties were produced through compression molding using fine expanded perlite microspheres (<90 μm) up to an infill ratio of 40 vol.%. Fine fillers (<90 μm) performed well in FDM, allowing printing of composite dogbone samples with a higher Young’s modulus and elongation and similar ultimate tensile strength compared to benchmark, up to an infill ratio of 20 vol.%. Composite samples present a slightly lower burning rate compared to those produced solely by ABS. Perlite microspheres present good workability in both applications, possessing satisfactory performance as filler in the composites, and can thus be assumed a promising multifunctional filler for various thermoplastics considering their low price, environmental impact, and fire rating. 相似文献
90.
Andreu GL Maurmann N Reolon GK de Farias CB Delgado R Roesler R 《Arzneimittel-Forschung》2011,61(7):382-385
Mangiferin (1,3,6,7-tetrahydroxy-2-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl] -xanthen-9-one, CAS 4773-96-0), a naturally occurring glucosylxanthone, is widely distributed in higher plants and a constituent of folk medicine. In the present study the effect of systemic administration of mangiferin on behavioural outcomes of neurological function in normal rats was investigated. A single intraperitoneal injection of mangiferin (10, 50 and 100 mg/kg body weight) immediately post-training produced an impairment of long-term memory for aversive training and a reduced freezing in a dose independent manner, when given immediately post-training. The administration of mangiferin 6 h post-training did not affect fear memory. The results indicate that mangiferin might induce deficits of emotionally motivated memory. 相似文献