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Background: Previous studies demonstrated that induction chemotherapy (IC) followed by de-escalated chemoradiotherapy adapted to tumor response was effective in treating childhood nasopharyngeal carcinoma (NPC), but the toxicity profile of this treatment strategy, and whether childhood patients with advanced stages can obtain enough benefits from it requires further investigation. Methods: We conducted a single-center phase II trial (NCT03020329). All participants received 3 cycles of paclitaxel liposome, cisplatin and 5-fluorouracil (TPF)-based IC. Patients who showed complete or partial response received de-escalated radiotherapy of 60 Gy with 3 cycles of concurrent cisplatin, and those who showed stable or progressive disease received standard-dose radiotherapy of 70 Gy with concurrent cisplatin. The primary endpoint was the complete response (CR) rate at the end of concurrent chemoradiotherapy (CCRT). Findings: From November 2016 to March 2021, 44 patients were recruited in the cohort. The CR rate was 80% (35/44, 95% CI, 65-90) of the whole cohort. All patients achieved CR 3 months after CCRT. By the last follow-up, the 3-year progression-free survival and overall survival were 91% (95% CI, 82-99) and 100% respectively. Dry mouth was the most common late toxicity, with an incidence of 41% (18/44), followed by skin fibrosis and hearing impairment. No patient suffered from severe late toxicity and growth retardation. Interpretation: Our results proved the efficacy and safety of TPF regimen followed by de-escalated radiotherapy with concurrent cisplatin in treating stage IVa-b childhood NPC patients. Funding: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

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BACKGROUND: The processabilities and mechanical properties of natural rubber depend greatly on its molecular weight (MW) and molecular weight distribution (MWD). However, the mechanisms underlying the regulation of molecular weight during rubber biosynthesis remain unclear. RESULTS: In the present study, we determined the MW and particle size of latex from 1-year-old virgin trees and 30-year-old regularly tapped trees of the Hevea clones Reyan7-33-97 and RRIM600. The results showed that both the MW and the particle size of latex varied between these two clones and increased with tree age. Latex from RRIM600 trees had a smaller average particle size than that from Reyan7-33-97 trees of the same age. In 1-year-old trees, the Reyan7-33-97 latex displayed a slightly higher MW than that of RRIM600, whereas in 30-year-old trees, the RRIM600 latex had a significantly higher MW than the Reyan7-33-97 latex. Comparative analysis of the transcriptome profiles indicated that the average rubber particle size is negatively correlated with the expression levels of rubber particle associated proteins, and that the high-MW traits of latex are closely correlated with the enhanced expression of isopentenyl pyrophosphate (IPP) monomer-generating pathway genes and downstream allylic diphosphate (APP) initiator-consuming non-rubber pathways. By bioinformatics analysis, we further identified a group of transcription factors that potentially regulate the biosynthesis of IPP. CONCLUSIONS: Altogether, our results revealed the potential regulatory mechanisms involving gene expression variations in IPP-generating pathways and the non-rubber isoprenoid pathways, which affect the ratios and contents of IPP and APP initiators, resulting in significant rubber MW variations among same-aged trees of the Hevea clones Reyan7-33-97 and RRIM600. Our findings provide a better understanding of rubber biosynthesis and lay the foundation for genetic improvement of rubber quality in H. brasiliensis.

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This study aimed to investigate the clinical characteristics, prognosis, and factors for survival of patients who underwent early-start peritoneal dialysis (PD) within 24 h after catheter insertion three years after PD. This study was conducted from January 1, 2013 to December 31, 2017. All adult patients who were diagnosed with end-stage renal disease (ESRD) and underwent PD for the first time within 24 h after catheter insertion in our hospital were included. All patients with PD were followed-up until they withdrew from PD, switching to hemodialysis, were transferred to other medical centers, underwent renal transplantation, died or were lost to follow-up, or continued to undergo dialysis until the end of the study period. The follow-up observation lasted three years. The number of eligible patients was 110, and switching to hemodialysis and death were the main reasons for patients to withdraw from PD. The 1-, 2-, and 3-year technical survival rates of patients were 89.1, 79.1, and 79.1% respectively, while the 1-, 2- and 3-year survival rates were 90, 81.8, and 81.8%, respectively. The Charlson comorbidity index, age, hemoglobin, serum albumin, diabetic nephropathy, chronic glomerulonephritis, and hypertensive renal damage were independent risk factors that affected the prognosis of PD patients. Under the condition of ensuring the quality of the PD catheter insertion, early-start PD within 24 h after catheter insertion is a safe treatment approach for ESRD patients.

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This study aimed to investigate the clinical characteristics, prognosis, and factors for survival of patients who underwent early-start peritoneal dialysis (PD) within 24 h after catheter insertion three years after PD. This study was conducted from January 1, 2013 to December 31, 2017. All adult patients who were diagnosed with end-stage renal disease (ESRD) and underwent PD for the first time within 24 h after catheter insertion in our hospital were included. All patients with PD were followed-up until they withdrew from PD, switching to hemodialysis, were transferred to other medical centers, underwent renal transplantation, died or were lost to follow-up, or continued to undergo dialysis until the end of the study period. The follow-up observation lasted three years. The number of eligible patients was 110, and switching to hemodialysis and death were the main reasons for patients to withdraw from PD. The 1-, 2-, and 3-year technical survival rates of patients were 89.1, 79.1, and 79.1% respectively, while the 1-, 2- and 3-year survival rates were 90, 81.8, and 81.8%, respectively. The Charlson comorbidity index, age, hemoglobin, serum albumin, diabetic nephropathy, chronic glomerulonephritis, and hypertensive renal damage were independent risk factors that affected the prognosis of PD patients. Under the condition of ensuring the quality of the PD catheter insertion, early-start PD within 24 h after catheter insertion is a safe treatment approach for ESRD patients.

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BACKGROUND: Antibodies to saccharomyces cerevisiae (ASCA), antibodies to perinuclear anti-neutrophil cytoplasmic (pANCA), pancreatic autoantibodies (PAB) and antibodies against intestinal goblet cells (GAB) are important in diagnosing Crohn's disease (CD) and ulcerative colitis (UC). However, little is known about their diagnostic value in real clinical practice in China. This retrospective study aimed to present our 2-year clinical experience with those biomarkers in diagnosis of CD and UC. METHODS: A total of 140 patients with UC, 128 patients with CD, and 224 patients with intestinal associated diseases as disease controls were included. Serum ASCA were determined by ELISA. Serum pANCA, GAB, and PAB were tested by indirect immunofluorescent assay. Retrospective review of laboratory results and clinical information was performed. RESULTS: ASCA and ASCA+/pANCA- showed poor abilities in differentiating CD from UC, CD from intestinal Behçet's disease (BD), or CD from intestinal tuberculosis (ITB). In contrast, PAB exhibited good capacities in differentiating CD from UC, CD from intestinal BD, and CD from ITB. IgG pANCA demonstrated a high sensitivity and specificity in differentiating UC from CD. pANCA+/ASCA- or pANCA+/PAB- displayed a high sensitivity and specificity in differentiating UC from CD. GAB showed poor potential in differentiating UC from CD. PAB were positively correlated with early disease onset, ileocolonic disease, and perianal disease in CD patients. CONCLUSIONS: Our data suggest that pANCA and PAB are helpful in diagnosis of UC and CD, respectively, while ASCA and GAB were not. Our findings indicate a clear need for additional biomarkers for diagnosis of CD in China.

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Radiotherapy for malignancies in the head and neck can cause common complications that can result in tooth damage that are also known as radiation caries. The aim of this study was to examine damage to the surface topography and calculate changes in friction behavior and the nano-mechanical properties (elastic modulus, nanohardness and friction coefficient) of enamel and dentine from extracted human third molars caused by exposure to radiation. Enamel and dentine samples from 50 human third molars were randomly assigned to four test groups or a control group. The test groups were exposed to high energy X-rays at 2 Gy/day, 5 days/week for 5 days (10 Gy group), 15 days (30 Gy group), 25 days (50 Gy group), 35 days (70 Gy group); the control group was not exposed. The nanohardness, elastic modulus, and friction coefficient were analyzed using a Hysitron Triboindenter. The nano-mechanical properties of both enamel and dentine showed significant dose-response relationships. The nanohardness and elastic modulus were most variable between 30-50 Gy, while the friction coefficient was most variable between 0-10 Gy for dentine and 30-50 Gy for enamel. After exposure to X-rays, the fracture resistance of the teeth clearly decreased (rapidly increasing friction coefficient with increasing doses under the same load), and they were more fragile. These nano-mechanical changes in dental hard tissue may increase the susceptibility to caries. Radiotherapy caused nano-mechanical changes in dentine and enamel that were dose related. The key doses were 30-50 Gy and the key time points occurred during the 15th-25th days of treatment, which is when application of measures to prevent radiation caries should be considered.

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Abstract Radiotherapy for malignancies in the head and neck can cause common complications that can result in tooth damage that are also known as radiation caries. The aim of this study was to examine damage to the surface topography and calculate changes in friction behavior and the nano-mechanical properties (elastic modulus, nanohardness and friction coefficient) of enamel and dentine from extracted human third molars caused by exposure to radiation. Enamel and dentine samples from 50 human third molars were randomly assigned to four test groups or a control group. The test groups were exposed to high energy X-rays at 2 Gy/day, 5 days/week for 5 days (10 Gy group), 15 days (30 Gy group), 25 days (50 Gy group), 35 days (70 Gy group); the control group was not exposed. The nanohardness, elastic modulus, and friction coefficient were analyzed using a Hysitron Triboindenter. The nano-mechanical properties of both enamel and dentine showed significant dose-response relationships. The nanohardness and elastic modulus were most variable between 30-50 Gy, while the friction coefficient was most variable between 0-10 Gy for dentine and 30-50 Gy for enamel. After exposure to X-rays, the fracture resistance of the teeth clearly decreased (rapidly increasing friction coefficient with increasing doses under the same load), and they were more fragile. These nano-mechanical changes in dental hard tissue may increase the susceptibility to caries. Radiotherapy caused nano-mechanical changes in dentine and enamel that were dose related. The key doses were 30-50 Gy and the key time points occurred during the 15th-25th days of treatment, which is when application of measures to prevent radiation caries should be considered.

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In the present study the antiviral properties of the bacteriocin subtilosin against Herpes simplex virus type 1 (HSV-1) and the safety and efficacy of a subtilosin-based nanofiber formulation were determined. High concentrations of subtilosin, the cyclical antimicrobial peptide produced by Bacillus amyloliquefaciens, were virucidal against HSV-1. Interestingly, at non-virucidal concentrations, subtilosin inhibited wild type HSV-1 and aciclovir-resistant mutants in a dose-dependent manner. Although the exact antiviral mechanism is not fully understood, time of addition experiments and western blot analysis suggest that subtilosin does not affect viral multiplication steps prior to protein synthesis. Poly(vinyl alcohol) (PVOH)-based subtilosin nanofibers with a width of 278 nm were produced by the electrospinning process. The retained antimicrobial activity of the subtilosin-based fibers was determined via an agar well diffusion assay. The loading capacity of the fibers was 2.4 mg subtilosin/g fiber, and loading efficiency was 31.6%. Furthermore, the nanofibers with and without incorporated subtilosin were shown to be nontoxic to human epidermal tissues using an in vitro human tissue model. Taking together these results subtilosin-based nanofibers should be further studied as a novel alternative method for treatment and/or control of HSV-1 infection.

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A 10 kb fragment containing fliF, fliH, fliN, motA, flbD, flhA, flhF and fleN genes was cloned from the genomic DNA of Azospirillum brasilense Yu62. These eight genes appear to be structurally organized as an operon. FlbD, encoded by flbD, has a HTH DNA binding domain and shows homology to sigma(54)-dependent transcriptional activators such as NtrC, NifA and DctD. An in-frame deletion of flbD in A. brasilense abolishes biosynthesis of lateral flagella and swarming ability when grown on semi-solid surfaces. An intact copy of flbD on a plasmid complemented the DeltaflbD mutant by restoring lateral flagellation and swarming ability. Transcriptional analysis demonstrated that FlbD is involved in the genetic regulation of flagella biosynthesis and acts as both an activator and a repressor of flagellum gene expression in A. brasilense. DNA binding assays indicated direct interaction between FlbD and the promoter regions of laf1, fliF and flgB genes. We propose that A. brasilense has a genetic regulation profile for flagella biosynthesis similar to that observed in Caulobacter crescentus.

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Regulation of NifA activity in Azospirillum brasilense depends on GlnB (a PII protein), and it was previously reported that the target of GlnB activity is the N-terminal domain of NifA. Furthermore, mutation of the Tyr residue at position 18 in the N-terminal domain resulted in a NifA protein that did not require GlnB for activity under nitrogen fixation conditions. We report here that a NifA double mutant in which the Tyr residues at positions 18 and 53 of NifA N-were simultaneously replaced by Phe (NifA-Y1853F) displays high nitrogenase activity, which is still regulatable by ammonia, but not by GlnB. The yeast two-hybrid technique was used to investigate whether GlnB can physically interact with wild-type and mutant NifA proteins. GlnB was found to interact directly with the N-terminal GAF domain of wild-type NifA, but not with its central or C-terminal domain. GlnB could still bind to the single NifA mutants Y18F and Y53F. In contrast, no interaction was detected between GlnB and the double mutant NifA-Y18/53F or between GlnB and NifA-Y43.

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