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31.
32.
  • DNA is the sequence that codes for proteins.
  • Messenger RNA is transcribed from the DNA sequence of genes and translated into protein.
  • It can be difficult to predict how a change in the DNA sequence will affect messenger RNA and protein quantity and quality.
  • DNA translocation changes can cause the joining of sequences from two different genes or different parts of the same gene.
  • DNA sequencing is often used clinically to predict how DNA changes might affect proteins.
  • Alternatively, RNA sequencing can be used as a more direct measure of the effect of DNA changes on the protein products.
  • This sequencing is important for identifying changes in cancer that may indicate response to targeted therapy, prognosis, or diagnosis.
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《Cirugía espa?ola》2023,101(2):116-122
IntroductionMetastasis is remaining one of the major problems in cancer treatment. Like many other malignancies, urogenital tumors originating from kidney, prostate, testes, and bladder tend to metastasize to the lungs.The aim of this retrospective study is to evaluate the operative results and prognosis of pulmonary metastasectomy in patients with primary urogenital tumors.MethodsThis study was approved by the local ethical committee. We retrospectively analyzed the surgical and oncological results of patients who underwent lung resections for urogenital cancer metastases in our department between 2002 and 2018. Demographic data and clinicopathological features were extracted from the medical records. Survival outcomes according to cancer subtypes and early postoperative results of VATS and thoracotomy were analyzed.Results22 out of 126 patients referred for pulmonary metastasectomy to our department had metastases from urogenital tumors. These patients consisted of 17 males and five females. Their metastasis originated from renal cell carcinoma (RCC; n = 9), bladder tumor (n = 7), testis tumors (n = 4), and prostate cancer (n = 2). There was no intraoperative complication. Postoperative complications were seen in 2 patients.ConclusionsAlthough pulmonary metastasectomy in various types of tumors is well known and documented, the data is limited for metastases of urogenital cancers in the literature. Despite the limitations of this study, we aim to document our promising results of pulmonary metastasectomy in patients with primary urogenital tumors and wanted to emphasize the role of minimally invasive approaches.  相似文献   
35.
PurposeTo evaluate in vivo parameters as biomarkers of limbal stem cell function and to establish an objective system that detects and stage limbal stem cell deficiency (LSCD).MethodsA total of 126 patients (172 eyes) with LSCD and 67 normal subjects (99 eyes) were included in this observational cross-sectional comparative study. Slit-lamp biomicroscopy, in vivo laser scanning confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT) were performed to obtain the following: clinical score, cell morphology score, basal cell density (BCD), central corneal epithelial thickness (CET), limbal epithelial thickness (LET), total corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and tortuosity coefficient. Their potential correlations with the severity of LSCD were investigated, and cutoff values were determined.ResultsAn increase clinical score correlated with a decrease in central cornea BCD, limbal BCD, CET, mean LET, maximum LET, CNFL, CNFD, CNBD, and tortuosity coefficient. Regression analyses showed that central cornea BCD, CET and CNFL were the best parameters to differentiate LSCD from normal eyes (Coef = 3.123, 3.379, and 2.223; all p < 0.05). The rank correlation analysis showed a similar outcome between the clinical scores and the central cornea BCD (ρ = 0.79), CET (ρ = 0.82), and CNFL (ρ = 0.71). A comprehensive LSCD grading formula based on a combination of these parameters was established.ConclusionsA comprehensive staging system combining clinical presentation, central cornea BCD, CET, and CNFL is established to accurately and objectively diagnose LSCD and stage its severity.  相似文献   
36.
PurposeTo assess the cost effectiveness of microwave ablation (MWA) and stereotactic body radiotherapy (SBRT) for patients with inoperable stage I non–small cell lung cancer (NSCLC).Materials and MethodsA literature search was performed in MEDLINE with broad search clusters. A decision-analytic model was constructed over a 5-year period. The model incorporated treatment-related complications and long-term recurrence. All clinical parameters were derived from the literature with preference to long-term prospective trials. A healthcare payers’ perspective was adopted. Outcomes were measured in quality-adjusted life years (QALYs) extracted from prior studies and U.S. dollars from Medicare reimbursements and prior studies. Base case calculations, probabilistic sensitivity analysis with 10,000 Monte Carlo simulations, and multiple 1- and 2-way sensitivity analyses were performed.ResultsMWA yielded a health benefit of 2.31 QALYs at a cost of $195,331, whereas SBRT yielded a health benefit of 2.33 QALYs at a cost of $225,271. The incremental cost-effectiveness ratio was $1,480,597/QALY, indicating that MWA is the more cost-effective strategy. The conclusion remains unchanged in probabilistic sensitivity analysis with MWA being the optimal cost strategy in 99.84% simulations. One-way sensitivity analyses revealed that MWA remains cost effective when its annual recurrence risk is <18.4% averaged over 5 years, when the SBRT annual recurrence risk is >1.44% averaged over 5 years, or when MWA is at least $7,500 cheaper than SBRT.ConclusionsMWA appears to be more cost effective than SBRT for patients with inoperable stage I NSCLC.  相似文献   
37.
The 2021 WHO Classification of Thoracic Tumours was published earlier this year, with classification of lung tumors being one of the chapters. The principles remain those of using morphology first, supported by immunohistochemistry, and then molecular techniques. In 2015, there was particular emphasis on using immunohistochemistry to make classification more accurate. In 2021, there is greater emphasis throughout the book on advances in molecular pathology across all tumor types. Major features within this edition are (1) broader emphasis on genetic testing than in the 2015 WHO Classification; (2) a section entirely dedicated to the classification of small diagnostic samples; (3) continued recommendation to document percentages of histologic patterns in invasive nonmucinous adenocarcinomas, with utilization of these features to apply a formal grading system, and using only invasive size for T-factor size determination in part lepidic nonmucinous lung adenocarcinomas as recommended by the eighth edition TNM classification; (4) recognition of spread through airspaces as a histologic feature with prognostic significance; (5) moving lymphoepithelial carcinoma to squamous cell carcinomas; (6) update on evolving concepts in lung neuroendocrine neoplasm classification; (7) recognition of bronchiolar adenoma/ciliated muconodular papillary tumor as a new entity within the adenoma subgroup; (8) recognition of thoracic SMARCA4-deficient undifferentiated tumor; and (9) inclusion of essential and desirable diagnostic criteria for each tumor.  相似文献   
38.
《Cancer cell》2022,40(8):835-849.e8
  1. Download : Download high-res image (220KB)
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39.
目的研究利用经聚乙烯亚胺(PEI)钝化的荧光碳点(CD)装载阿霉素(DOX)进行药物递送,旨在增加DOX对非小细胞肺癌的治疗作用,减少DOX的心肌毒性。 方法通过一步微波加热法将甘油和PEI的混合物制备成CD-PEI,并通过静电效应将DOX装载至CD-PEI。采用CCK8实验检测CD-PEI-DOX对非小细胞肺癌细胞A549的增殖能力的影响;Transwell实验评估CD-PEI-DOX对A549细胞迁移侵袭能力的影响;最后通过体内动物实验评估CD-PEI-DOX的心肌毒性以及对非小细胞肺癌皮下肿瘤生长的抑制效果。 结果体外细胞实验证实,对比单纯的DOX处理组,CD-PEI-DOX对非小细胞肺癌A549细胞增殖、迁移侵袭能力的抑制作用更为显著。体内实验证实,CD-PEI-DOX纳米复合物治疗组小鼠心肌细胞结构完整,并且能有效抑制小鼠皮下肺癌肿瘤的生长。 结论经PEI钝化的荧光碳点负载阿霉素能显著提高DOX对非小细胞肺癌的治疗效果,并减少DOX对心脏的毒性作用。运用CD-PEI纳米颗粒改善化疗药物递送的治疗方案取得了初步证实,这可为肺癌化学治疗提供新思路,具有广大的临床应用前景。  相似文献   
40.
Purpose: The medicinal plant Ipomoea aquatica belonging to convulvulaceae family is an effective natural herb for treatment of various ailments and possesses effective anticancer activity. The aim of the work is to characterize a secondary metabolite merromoside (a resin glycoside) for anti-breast cancer activity through down regulation of ROS species. Methods: The Extract of the whole plant has been prepared by maceration method using 50%v/v ethanol in distilled water to get a hydroalcoholic extract. The phytochemical evaluation reveals that the active secondary metabolite was isolated by using column chromatographic technique. The isolated compound was evaluated for its anticancer properties through invitro method such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay on Michigan Cancer Foundation-7 Cell lines. The purity and structural characterization were done by high-performance thin layer chromatography, Fourier Transform Infrared Spectroscopy, Proton and13C Nuclear Magnetic Resonance spectroscopy and Liquid Chromatography–Mass Spectrometry. Results: The isolated compound (W04) from the derived extract showed Rf value of 0.79 that showed IC50 of 182.8μg/ml. The chemical structure of W04 has been confirmed as [4,5-dihydroxy-6-[5-hydroxy-2-methyl-4-(2-methylpropanoyloxy)-6-[(24,25,26-trihydroxy-5,23-dimethyl-9-oxo-19-pentyl-2,4,8,20,22-pentaoxatricyclo[19.2.2.13,7]hexacosan-6-yl)oxy]oxan-3-yl]oxy-2-methyloxan-3-yl] 2-methyl propanoate with the molecular weight of 979.15268. The isolated compound merromoside from hydroalcoholic extract of Ipomoea aquatica has been evaluated for anti-breast cancer properties. The down regulation of ROS species will prevent reverse signalling and angiogenesis. This indicates that merromoside will overcome MDR in breast cancer especially DOX-resistant.  相似文献   
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