Inverse design and optimization of an aperiodic multi-notch fiber Bragg grating using neural networks.

Recent developments in the application of aperiodic fiber Bragg gratings (AFBGs) in astrophotonics, such as AFBG for astronomical near-infrared OH suppression and gas detection based on cross-correlation spectroscopy, have illuminated the problem that the optimization for AFBG with certain fabrication constraints has not been fully investigated and solved. Previous solutions will either sacrifice part of the spectral features or consume a significant amount of computation resources and time. Inspired by recently successful applications of artificial neural networks (ANNs) in photonics inverse design, we develop an AFBG optimization approach employing ANNs in conjunction with genetic algorithms (GAs) for the first time, to the best of our knowledge. The approach maintains the spectral notch depths and preserves the fourth-order super-Gaussian spectral features with improvements of interline loss by ∼100 times. We also implement, to our knowledge, the first inverse scattering neural network based on a tandem architecture for AFBG, using a first-order Gaussian notch profile. The neural network successfully converges but has a poor predictive capability for the phase part of the design. We discuss possible ways to overcome these limitations.

Enteral immunonutrition versus enteral nutrition for patients undergoing esophagectomy: a randomized controlled trial.

BACKGROUND: In recent years, immunonutrition has been introduced and proposed to have a positive modulatory effect on inflammatory and immune responses and gut function for surgical patients, especially for patients undergoing gastrointestinal cancer resection. We conducted this parallel-group, randomized and double-blind clinical controlled trial to investigate the efficacy of perioperative enteral immunonutrition (EIN) on clinical and immunological outcomes of patients undergoing esophageal resection. METHODS: A randomized, parallel-group, double-blind, clinical trial was conducted between December 1, 2017 and March 1, 2018. This study enrolled 120 patients with esophageal cancer. And 112 patients were divided into two groups randomly: EIN group and enteral nutrition (EN) group. The EIN contained extra immunonutritional substrates, including a consistent combination of arginine, RNA and the omega-3 fatty acids compared with EN. Immune indicators were measured at preoperative day 7, postoperative day (POD) 1, 3, 7 and post-discharge day (PDD) 30. RESULTS: There were 56 participants randomized to each group. Finally, 53 patients in EIN and 50 patients in EN were analyzed. Immune indicator was the primary outcome in this study. EIN yielded a significantly lower rate of CD8/CD3 (%) at POD 3 compared with EN group (P=0.005). The rate of CD4/CD8 (%) in EIN group was higher than that in EN group at POD3 (P=0.004). The serum levels of IgM at POD 3 and 7 were significantly higher in EN group compared with EIN group (P=0.025 and P=0.009, respectively). The rate of NK (%) and the serum level of IgA were significantly higher in EIN group compared with EN group at PDD 30 (P=0.022 and P=0.041, respectively). No significant differences were found in 2-year progressionfree survival and overall survival. CONCLUSIONS: Immunonutrition is a safe and feasible nutritional treatment, which has a positive modulatory impact on immune responses after esophagectomy. Although no significant difference was found in clinical and survival outcomes between EIN and EN groups, immunonutrition could still have a positive effect on immunological function of patients undergoing esophagectomy.

Quercetin Downregulates Cyclooxygenase-2 Expression and HIF-1α/VEGF Signaling-Related Angiogenesis in a Mouse Model of Abdominal Aortic Aneurysm.

OBJECTIVE: Abdominal aortic aneurysm (AAA) development has been characterized by increased expression of vascular endothelial growth factor (VEGF), which contributes to angiogenesis via cyclooxygenase-2 (COX-2). Quercetin, one of the most common and well-researched flavonoids and abundant in vegetables and fruits, has beneficial effects in inhibiting angiogenesis. This study investigated the antiangiogenic effects of quercetin on experimental aneurysms. METHODS: We utilized the in vivo AAA mouse model induced by the periaortic application of CaCl2 to examine the effectiveness of quercetin in blocking angiogenesis. Quercetin was administered at 60 mg/kg once daily on the day of the AAA induction and then continued for 6 weeks. Celecoxib, a selective COX-2 inhibitor, was used as the positive control. RESULTS: Our results demonstrated that quercetin significantly attenuated aneurysm growth in AAA mice and medial neovascularization. Accordingly, quercetin decreased the expression of proangiogenic mediators, including VEGF-A, intercellular adhesion molecule-1, vascular cell adhesion molecule 1, and vascular endothelial cadherin. Quercetin treatment also inhibited the expression of COX-2 and hypoxia-inducible factor 1α (HIF-1α). It was also found that quercetin-3-glucuronide, a major quercetin metabolite, downregulated the expression of COX-2, HIF-1α, VEGF-A, and matrix metalloproteinase activities in aortic vascular smooth muscle cells isolated from AAA mice. CONCLUSION: Quercetin attenuates neovascularization during AAA growth, and this effect is mediated via the inhibition of COX-2, which decreases HIF-1α/VEGF signaling-related angiogenesis.

Prognostic Significance of microRNA-7 and its Roles in the Regulation of Cisplatin Resistance in Lung Adenocarcinoma.

BACKGROUND: Previously, microRNA (miR)-7 has been reported to function as a tumor suppressor in human cancers, but the correlations of miR-7 expression with prognosis and cisplatin (CDDP) resistance in lung adenocarcinoma (LA) are unclear. Here, our aim is to determine the prognostic significance of miR-7 and its roles in the regulation of CDDP resistance in LA. METHODS: Quantitative real-time PCR (qRT-PCR) assay was performed to determine miR-7 expression in 108 paired of LA tissues and analyze its correlations with clinicopathological factors of patients. The patient survival data were collected retrospectively by Kaplan-Meier analyses, and multivariate analysis was performed using the Cox proportional hazards model to determine the prognostic significance of miR-7 expression. The effects of miR-7 expression on the chemosensitivity of LA cells to CDDP and its possible mechanisms were evaluated by MTT, flow cytometry, Western blot and luciferase assays. RESULTS: It was observed that the relative expression level of miR-7 in LA tissues was significantly lower than that in the adjacent normal tissues and low miR-7 expression level was closely associated with poorer tumor differentiation, advanced pathological T-factor, higher incidence of lymph node metastasis and advanced p-TNM stage. Also, patients with low miR-7 expression showed a shorter overall survival than those with high miR-7 expression, and multivariate analysis indicated that status of miR-7 expression was an independent molecular biomarker for predicting the overall survival (OS) of LA patients. In addition, upregulation of miR-7 increases the sensitivity of LA cells to CDDP via induction of apoptosis by targeting Bcl-2. CONCLUSIONS: Our finding for the first time demonstrates that low miR-7 expression may be an independent poor prognostic factor and targeting miR-7 may be a potential strategy for the reversal of CDDP resistance in LA.

PiggyBac transposon vectors: the tools of the human gene encoding.

A transposon is a DNA segment, which is able to change its relative position within the entire genome of a cell. The piggyBac (PB) transposon is a movable genetic element that efficiently transposes between vectors and chromosomes through a "cut-and-paste" mechanism. During transposition, the PB transposase recognizes transposon-specific inverted terminal repeats (ITRs) sequences located on both ends of the transposon vector and eight efficiently moves the contents from its original positions and efficiently integrates them into TTAA chromosomal sites. PB has drawn much attention because of its transposition efficiency, safety and stability. Due to its priorities, PB can be used as a new genetic vehicle, a new tool for oncogene screening and a new method for gene therapy. PB has created a new outlook for human gene encoding.

N-acetylcysteine to ameliorate acute renal injury in a rat cardiopulmonary bypass model.

OBJECTIVE: Oxidative stress and systemic inflammation response contribute to acute renal injury post cardiac surgery. We hypothesized that administration of the antioxidant N-acetylcysteine would be beneficial to renal function after cardiopulmonary bypass in a rat model. METHODS: Male Sprague-Dawley rats were divided into four groups (each n = 6): sham group, cardiopulmonary bypass group, and two N-acetylcysteine-treated cardiopulmonary bypass groups (bolus doses of 200 and 500 mg/kg in cardiopulmonary bypass prime). Blood samples were collected at the beginning of cardiopulmonary bypass, at the cessation of cardiopulmonary bypass, and at 2 and 12 postoperative hours. The kidneys were harvested at 12 postoperative hours. RESULTS: Serum creatinine and cystatin C continuously increased in all cardiopulmonary bypass groups (P < .05 within groups). Tubular dilatation, tubular necrosis, and vacuole formation were found in epithelial cells in histomorphologic studies of the cardiopulmonary bypass groups, but N-acetylcysteine significantly reversed these effects (P < .05 between groups). Compared with the sham group, the reduced glutathione hormone content and the superoxide dismutase and catalase activities decreased in the cardiopulmonary bypass groups (P < .01). N-acetylcysteine-treated groups had higher levels of these antioxidants than the untreated bypass group (P < .05). Renal malondialdehyde, tumor necrosis factor alpha, and nuclear factor kappaB were notably increased in all cardiopulmonary bypass groups relative to the sham group (P < .01), and N-acetylcysteine attenuated these changes dose dependently. CONCLUSION: Administration of the antioxidant N-acetylcysteine preserved renal function after cardiopulmonary bypass dose dependently. Furthermore, oxidative stress and systemic inflammation were significantly reduced in the treated animals.

Cystatin C as a reliable marker of renal function following heart valve replacement surgery with cardiopulmonary bypass.

BACKGROUND: Little is known about serum cystatin C as a marker of renal function in cardiac surgery patients. The aim of this study was to assess its utility post cardiopulmonary bypass (CPB). METHODS: 60 heart valve replacement patients were enrolled, and 26 of them had low-dose corticosteroid treatment on the first 3 days postoperatively. Serum creatinine, serum cystatin C and 24-h creatinine clearance rate (CCR) adjusted by body surface area were determined preoperation, days 1, 2, 3, 7 post operation. RESULTS: Serum creatinine increased and peaked at day 3 postoperatively, while cystatin C peaked at day 2, and the adjusted CCR also reached a minimum at day 2. The inverse of cystatin C correlated better with CCR than that of creatinine (r=0.751 vs. 0.629). Using adjusted CCR as "golden standard", cystatin C was superior to creatinine in diagnosing renal dysfunction (area under the curve [AUC] for cystatin C 0.876, 95% confidence interval 81.8-93.4; AUC for creatinine 0.801, 95% confidence interval 72.5-87.7; p=0.045). Low-dose corticosteroid treatment has no significant effect on cystatin C. CONCLUSION: In agreement with many other investigators, the present findings support cystatin C is a reliable marker of renal function. It is superior to creatinine in patients post CPB.