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191.
Ciro Franzese Antonella Fogliata Mauro Loi Marco Badalamenti Davide Franceschini Tiziana Comito Luca Cozzi Giacomo Reggiori Stefano Tomatis Marta Scorsetti 《Reports of Practical Oncology and Radiotherapy》2021,26(1):101
BackgroundThe purpose of the study was to evaluate the toxicity and outcome of nasopharyngeal carcinoma patients treated using 3-dimensional conformal radiotherapy (3DCRT) or volumetric modulated arc therapy (VMAT) technique.Materials and methods68 patients treated between 2006 and 2018 were retrospectively analysed. Since 2009 patients received 3DCRT with 50/70 Gy to the elective/boost volumes in 35 fractions; from then, VMAT with simultaneous integrated boost (SIB) with 54.45/69.96 Gy in 33, or 54/66 Gy in 30 fractions. Induction chemotherapy was administered in 74% of the patients, concomitant cisplatinum in 87%. Acute and late toxicity data, progression-free survival PSF and overall survival OS, and toxicity correlations with dose metrics were reported.ResultsWith a median follow-up of 64 months, complete remission at the last evaluation was in 68% of the patients, while 28% and 9% had locoregional relapse and distant disease, respectively. The 5- and 10-year progression free survival (PFS) rates were 62.7 ± 6.5% and 53.2 ± 8.7%, respectively. The 5- and 10-year OS rates were 78.9 ± 5.5% and 61.4 ± 9.2%, respectively. At the multivariate Cox analysis TNM stage (p = 0.02) and concomitant chemotherapy (p = 0.01) resulted significant for PFS, concomitant chemotherapy (p = 0.04) for OS.Improvements in acute toxicity were presented for VMAT patients due to its ability to spare OARs. Odds ratio (OR) for acute salivary toxicity, between VMAT and 3DCRT, was 4.67 (p = 0.02). Dosimetrically, salivary toxicity correlated with mean parotid dose (p = 0.05), dysphagia with laryngeal (p = 0.04) and mean oral cavity (p = 0.06) doses, when dose-volume histograms (DVHs) are corrected for fractionation.ConclusionThis study is a proof of a significant benefit of the VMAT technique compared with 3DCRT in terms of side effects in nasopharynx patients, and adds dosimetric correlations. 相似文献
192.
Recent evidence indicates that bone-marrow cells (BMCs) can contribute to the healing process of the injured cardiovascular system via the chemokine receptor CXCR4/SDF-1, thymosin beta(4) and integrin alpha(4)beta(1) molecular pathways. During tissue ischemia overwhelming numbers of detrimental oxygen radicals are generated, and therefore treatment with antioxidants and L-arginine, the precursor of nitric oxide (NO), could induce beneficial effects beyond those achieved by BMC transplantation alone. Recent studies have reported that BMCs have enhanced neovascularization capacity in cotreatment with alpha-tocopherol (vitamin E), ascorbic acid (vitamin C) and L-arginine. Moreover, BMC therapy can be combined with gene therapy. Clinical trials employing BMCs in the treatment of cardiovascular diseases have been completed with mixed or positive results, and several trials are ongoing. Here, we discuss the clinical potential of BMC transplantation alone and in combined therapy that aims to restore organ vascularization and function. We also consider the mechanisms of mobilization, differentiation and incorporation of BMCs. 相似文献
193.
Stefania Barbato Gennaro Piccialli Ciro Santacroce Lorenzo De Napoli Luciano Mayol 《Nucleosides, nucleotides & nucleic acids》2013,32(4):867-882
Abstract The synthesis on a polyacrylamide resin of oligonucleotides containing 5,6-dihydroimidazo [1, 2-c] pyrimidin-5-one (X) as a base residue is described. Perliminary results on enzymatic hydrolysis of the modified octanucleotide d(TXAATTCA) (21), containing. the recognition sequence for the endonuclease -ECO RI where dG is replaced by dX (1), are reported. 相似文献
194.
Stefania Barbato Gennaro Piccialli Ciro Santacroce Lorenzo De Napoli Luciano Mayol 《Nucleosides, nucleotides & nucleic acids》2013,32(4):853-866
Abstract The synthesis and the spectral characterization of a number of N4-N4 bridged pyrimidine nucleosides and triazo [4, 3-c] pyrimidine nucleoside analogues are reported. 相似文献
195.
In the beetle genus Tribolium, satellite DNAs comprise a significant amount of pericentromeric heterochromatin and are characterized by rapid turnover
resulting in species specific profiles. In the present work we characterize the major pericentromeric satellite DNA TCAST
of the beetle T. castaneum and analyse its population dynamics. Using direct sequencing of genomic PCR products we show that the TCAST satellite exists
in the form of two related subfamilies: Tcast1a and Tcast1b that make up 20 and 15% of the genome, respectively. Tcast1a and
Tcast1b have consensus sequences of 377 and 362 bp respectively, share an average similarity of 79% and are characterized
by a divergent, subfamily specific region of approximately 100 bp. The two subfamilies are prevalently organized in the interspersed
form, although a portion exists in the form of homogenous tandem arrays composed of only Tcast1a or Tcast1b. The pattern of
restriction enzyme digestion indicates that Tcast1a and Tcast1b are organized in composite higher order repeats. Comparison
of sequence variability of Tcast1a and Tcast1b among ten strains reveals a difference in the frequency of particular mutations
present at some positions. However, no difference in the organization and in the amount of subfamilies was detected among
strains. The results show that direct genomic sequencing can be a useful method for the detection of population specific features
of satellite DNA. In the case of TCAST satellite DNA, changes in the mutational profiles seem to represent the first step
in the genesis of a population specific satellite profile. 相似文献
196.
Biodegradation of bisphenols with immobilized laccase or tyrosinase on polyacrylonitrile beads 总被引:2,自引:0,他引:2
Nicolucci C Rossi S Menale C Godjevargova T Ivanov Y Bianco M Mita L Bencivenga U Mita DG Diano N 《Biodegradation》2011,22(3):673-683
The biodegradation of waters polluted by some bisphenols, endowed with endocrine activity, has been studied by means of laccase or tyrosinase immobilized on polyacrylonitrile (PAN) beads. Bisphenol A (BPA), Bisphenol B (BPB), Bisphenol F (BPF) and Tetrachlorobisphenol A (TCBPA) have been used. The laccase-PAN beads system has been characterized as a function of pH, temperature and substrate concentration. The biochemical parameters so obtained have been compared with those of the free enzyme to evidence the modification induced by the immobilization process. Once characterized, the laccase-PAN beads have been employed in a fluidized bed reactor to determine for each of the four bisphenols the degradation rate constant (k); the τ(50), i.e., the time to obtain the 50% of degradation, and the removal efficiency (RE(90)) after 90 min of enzyme treatment. The same parameters have been measured for each of the four pollutants with the same fluidized bed bioreactor loaded with tyrosinase-PAN beads. The internal comparison, i.e., in each of the two catalytic systems, has shown that both enzymes exhibit a removal efficiency in the following order BPF>BPA>BPB>TCBPA. The external comparison, i.e., the comparison between the two catalytic system, has shown that the catalytic power of laccase were higher than that of tyrosinase. The operational stability of both catalytic systems resulted excellent, since they maintained more than 80% of the initial activity after 30 days of work. 相似文献
197.
Costa MR Ortega F Brill MS Beckervordersandforth R Petrone C Schroeder T Götz M Berninger B 《Development (Cambridge, England)》2011,138(6):1057-1068
Little is known about the intrinsic specification of adult neural stem cells (NSCs) and to what extent they depend on their local niche. To observe adult NSC division and lineage progression independent of their niche, we isolated cells from the adult mouse subependymal zone (SEZ) and cultured them at low density without growth factors. We demonstrate here that SEZ cells in this culture system are primarily neurogenic and that adult NSCs progress through stereotypic lineage trees consisting of asymmetric stem cell divisions, symmetric transit-amplifying divisions and final symmetric neurogenic divisions. Stem cells, identified by their astro/radial glial identity and their slow-dividing nature, were observed to generate asymmetrically and fast-dividing cells that maintained an astro/radial glia identity. These, in turn, gave rise to symmetrically and fast-dividing cells that lost glial hallmarks, but had not yet acquired neuronal features. The number of amplifying divisions was limited to a maximum of five in this system. Moreover, we found that cell growth correlated with the number of subsequent divisions of SEZ cells, with slow-dividing astro/radial glia exhibiting the most substantial growth prior to division. The fact that in the absence both of exogenously supplied growth factors and of signals provided by the local niche neurogenic lineage progression takes place in such stereotypic fashion, suggests that lineage progression is, to a significant degree, cell intrinsic or pre-programmed at the beginning of the lineage. 相似文献
198.
Respiratory syncytial virus (RSV) causes acute exacerbations in COPD and asthma. RSV infects bronchial epithelial cells (HBE) that trigger RSV associated lung pathology. This study explores whether the phosphodiesterase 4 (PDE4) inhibitor Roflumilast N-oxide (RNO), alters RSV infection of well-differentiated HBE (WD-HBE) in vitro. WD-HBE were RSV infected in the presence or absence of RNO (0.1-100 nM). Viral infection (staining of F and G proteins, nucleoprotein RNA level), mRNA of ICAM-1, ciliated cell markers (digital high speed videomicroscopy, β-tubulin immunofluorescence, Foxj1 and Dnai2 mRNA), Goblet cells (PAS), mRNA of MUC5AC and CLCA1, mRNA and protein level of IL-13, IL-6, IL-8, TNFα, formation of H2O2 and the anti-oxidative armamentarium (mRNA of Nrf2, HO-1, GPx; total antioxidant capacity (TAC) were measured at day 10 or 15 post infection. RNO inhibited RSV infection of WD-HBE, prevented the loss of ciliated cells and markers, reduced the increase of MUC5AC and CLCA1 and inhibited the increase of IL-13, IL-6, IL-8, TNFα and ICAM-1. Additionally RNO reversed the reduction of Nrf2, HO-1 and GPx mRNA levels and consequently restored the TAC and reduced the H2O2 formation. RNO inhibits RSV infection of WD-HBE cultures and mitigates the cytopathological changes associated to this virus. 相似文献
199.
Discovery of a multispecies shark aggregation and parturition area in the Ba Estuary,Fiji Islands 下载免费PDF全文
Tom Vierus Stefan Gehrig Juerg M. Brunnschweiler Kerstin Glaus Martin Zimmer Amandine D. Marie Ciro Rico 《Ecology and evolution》2018,8(14):7079-7093
Population declines in shark species have been reported on local and global scales, with overfishing, habitat destruction and climate change posing severe threats. The lack of species‐specific baseline data on ecology and distribution of many sharks, however, makes conservation measures challenging. Here, we present a fisheries‐independent shark survey from the Fiji Islands, where scientific knowledge on locally occurring elasmobranchs is largely still lacking despite the location's role as a shark hotspot in the Pacific. Juvenile shark abundance in the fishing grounds of the Ba Estuary (north‐western Viti Levu) was assessed with a gillnet‐ and longline‐based survey from December 2015 to April 2016. A total of 103 juvenile sharks identified as blacktip Carcharhinus limbatus (n = 57), scalloped hammerhead Sphyrna lewini (n = 35), and great hammerhead Sphyrna mokarran (n = 11) sharks were captured, tagged, and released. The condition of umbilical scars (68% open or semihealed), mean sizes of individuals (±SD) (C. limbatus: 66.5 ± 3.8 cm, S. lewini: 51.8 ± 4.8 cm, S. mokarran 77.4 ± 2.8 cm), and the presence of these species over recent years (based on fishermen interviews), suggest that the Ba Estuary area is a critical habitat for multiple species that are classified as “Near Threatened” or “Endangered.” Specifically, the area likely acts as a parturition ground over the studied period, and potentially as a subsequent nursery area. We identified subareas of high abundance and found that temperature, salinity and depth acted as small‐scale environmental drivers of shark abundance. The data suggests a tendency for species‐specific spatial use, both horizontally (i.e., between sampling areas) and vertically (i.e., across the water column). These results enhance the understanding of shark ecology in Fiji and provide a scientific basis for the implementation of local conservation strategies that contribute to the protection of these threatened species. 相似文献
200.
María Teruel Jose-Ezequiel Martin Carlos González-Juanatey Raquel López-Mejias Jose A Miranda-Filloy Ricardo Blanco Alejandro Balsa Dora Pascual-Salcedo Luis Rodriguez-Rodriguez Benjamin Fernández-Gutierrez Ana M Ortiz Isidoro González-Alvaro Carmen Gómez-Vaquero Nunzio Bottini Javier Llorca Miguel A González-Gay Javier Martin 《Arthritis research & therapy》2011,13(4):R116-6