Ionic surfactants as assembly crosslinkers triggered supramolecular membrane with 2D↔3D conversion under multiple stimulus.

HYPOTHESIS: General strategies leading to 2D assemblies promise a significant step forward in the development of supramolecular materials with diversity and superiority. Considering molecular packing parameter indicates a connection between molecular geometry and aggregate morphology, we predict the introduction of ionic surfactants as assembly crosslinker would be endowed to develop a methodology of 2D supramolecular assembles. EXPERIMENTS: In this work, by introducing ionic surfactants such as sodium dodecylsulfate (SDS), the molecular packing parameter P in bolaamphiphile (A2G) system was increased, which successfully manipulated the transformation of the 3D vesicles into 2D membranes. This 2D membranes further showed excellent light and enzyme response, and thus 2D to 3D morphological conversion can be rationally controlled via UV/Vis light irradiation and alternate addition of ß-CD and α-amylase. Significantly, the 2D feature revealed not only a remarkable fluorescence enhancement to luminescent molecules but also the ability to effectively remove pollutants from water through filtration. FINDINGS: We report a general and facile strategy for the construction of 2D supramolecular membranes, initiated by introducing ionic surfactants as assembly crosslinker to increase P. In the existence of stimulus response factors, 2D↔3D morphological conversion can be further controlled in a flexible manner, which opens up a new paradigm leading to interconvertible supramolecular materials.

Reliability and validity of the mandarin version of the supportive care needs survey short-form (SCNS-SF34) and the head and neck cancer-specific supportive care needs (SCNS-HNC) module.

BACKGROUND: This study aimed to translate the English version of the supportive care needs scale of head and neck cancer patients (SCNS-HNC) questionnaire into Mandarin and to test the reliability and validity of the SCNS-SF34 and SCNS-HNC module in head and neck cancer patients. METHODS: The Mandarin version of the Supportive Care Needs Survey Short-Form (SCNS-SF34) and SCNS-HNC scales were used to assess 206 patients with head and neck cancer in Chengdu, China. Among them, 51 patients were re-tested 2 or 3 days after the first survey. The internal consistency of the scale was evaluated by Cronbach's alpha coefficient, the retest reliability of the scale was evaluated by retest correlation coefficient r, the structural validity of the scale was evaluated by exploratory factor analysis, and the ceiling and floor effects of the scale were evaluated. RESULTS: The Mandarin version of the SCNS-HNC had Cronbach's alpha coefficients greater than 0.700 (0.737 ≤ 0.962) for all of the domains. Except for the psychological demand dimension (r = 0.674) of the SCNS-SF34 scale, the retest reliability of the other domains was greater than 0.8. Three common factors were extracted by exploratory factor analysis, and the cumulative variance contribution rate was 64.39%. CONCLUSIONS: The Mandarin version of the SCNS-SF34 and SCNS-HNC demonstrated satisfactory reliability and validity and is able to measure the supportive care needs of Chinese patients with head and neck cancer. TRIAL REGISTRATION: ChiCTR, ChiCTR1900026635 . Registered 16 October 2019- Retrospectively registered.

Interactions of neuropeptide y, catecholamines, and angiotensin at the vascular neuroeffector junction.

Work from our laboratory has established that angiotensin II (Ang II) produces a greater enhancement of the nerve stimulation (NS)-induced release (overflow) of both norepinephrine (NE) and neuropeptide Y (NPY) and a greater increase in perfusion pressure of the mesenteric arterial bed obtained from the spontaneously hypertensive rat (SHR) compared to age-matched Wistar-Kyoto (WKY) or Sprague-Dawley rats. The enhancement of NS-induced NPY release was blocked by the AT1 receptor antagonist EMD 66684 and the AT2 receptor antagonist PD 123319. Both captopril and EMD 66684 decreased NPY and NE overflow from SHR mesenteric beds, suggesting an endogenous renin-angiotensin system (RAS) is active in the mesenteric artery. We also observed that the recently discovered new arm of the RAS, namely, angiotensin (1-7) (Ang-(1-7)), attenuated the NS-induced increase in NE and NPY release and the accompanied increased perfusion pressure. These inhibitory effects were greater in blood vessels obtained from SHR compared to WKY. We suggest that inhibition of sympathetic neurotransmission contributes to the mechanism(s) by which Ang-(1-7) acts to inhibit the vasoconstrictor effect of Ang II. Administration of the MAS receptor antagonist D-Ala(7)Ang-(1-7) attenuated the decrease in both NE and NPY release due to Ang-(1-7) administration. The AT2 receptor antagonist PD 123391 attenuated the effect of Ang-(1-7) on NE release without affecting the decrease in NPY release. We observed a shift in the balance between Ang II and Ang-(1-7) levels in the SHR with an increase in Ang II and a decrease in Ang-(1-7) in the blood and mesenteric artery. This appears to be due to an increase in angiotensin-converting enzyme (ACE) in the mesenteric artery of the SHR.

Does external pancreatic duct stent decrease pancreatic fistula rate after pancreatic resection?: a meta-analysis.

OBJECTIVES: The use of an external pancreatic duct stent to prevent fistula formation of pancreatic anastomosis remains a matter of debate. This study is a meta-analysis of the available evidence. METHODS: Articles published until the end of March 2011 comparing external stenting and non-stenting in pancreatic anastomosis were included. Pooled odds ratios (ORs) and weighted mean differences (WMDs) with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model. RESULTS: Six articles were identified for inclusion: 3 randomized controlled trials and 3 observational clinical studies. The meta-analysis revealed that the use of an external pancreatic duct stent was associated with a statistically significant reduction in overall postoperative morbidity (OR 0.56; 95% CI 0.39-0.81; p = 0.002), pancreatic fistula (OR 0.34; 95% CI 0.23-0.15; p < 0.001), severity of pancreatic fistula (OR 0.70; 95% CI 0.32-1.57; p = 0.04), delayed gastric emptying (OR 0.44; 95% CI 0.25-0.80; p = 0.007), and length of hospital stay (WMD -3.95; 95% CI -6.38 to -1.52; p = 0.001). CONCLUSIONS: The current literature suggests that the use of an external pancreatic duct stent reduced the leakage rate of pancreatic anastomosis after pancreatic resection. and IAP.

Neuropeptide Y induced attenuation of catecholamine synthesis in the rat mesenteric arterial bed.

The effect of neuropeptide Y (NPY) on the basal and nerve stimulation-induced increase in norepinephrine synthesis was studied in the isolated and perfused mesenteric arterial bed of the rat. Tyrosine hydroxylation, the rate-limiting step in catecholamine (CA) biosynthesis, was assessed by measuring the accumulation of DOPA in the perfusate/superfusate overflow after perfusion of the mesenteric arterial bed with the decarboxylase inhibitor m-hydroxybenzyl hydralazine (NSD-1015). Treatment with NDS-1015 resulted in a time-dependent increase in DOPA production and nerve stimulation (8 Hz, supramaximal voltage, 2 ms duration) increased DOPA production even further. NPY 1 to 100 nM was observed to produce a concentration-dependent attenuation in both the basal and nerve stimulation-induced increase in DOPA formation. To come to an understanding of the NPY receptor subtype mediating the inhibition of CA synthesis, the rank order of potency of a series of NPY analogs with varying selectivity for NPY receptor subtypes including intestinal polypeptide (PYY), PYY 13-36, Leu36 Pro34 NPY, human pancreatic polypeptide (h-PP), and rat pancreatic polypeptide (r-PP) were determined. In addition, the effect of various selective NPY antagonists on the inhibitory effect of NPY was also examined. These included the Y1 antagonist BIB03304, the Y2 antagonist BIIE0246, and the Y5 antagonist CGP71683. The IC50's for NPY, PYY, PYY13-36, Leu31 Pro34 NPY, and hPP in inhibiting CA synthesis were 5, 7, 15, 30, and 33 nM respectively. rPP failed to inhibit CA synthesis. All 3 of the NPY antagonists produced attenuation of the NPY-induced inhibition of CA synthesis, but it took a combination of all 3 to completely block the effect of a maximal inhibitory concentration of NPY. These results demonstrate that NPY inhibits CA synthesis in the perfused mesenteric arterial bed and can do so by activation of a variety of receptors including the Y1, Y2, and Y5.

Influence of cold stress on neuropeptide Y and sympathetic neurotransmission.

Chronic cold stress of rats (4 degrees C; 1-3 weeks) induced a marked increase in gene expression (adrenal medulla; superior cervical ganglia), tissue content (mesenteric arterial bed) and nerve stimulation-induced overflow of NPY-immunoreactivity (NPYir) from the perfused mesenteric arterial bed. In contrast increased NPY neurotransmission was offset by an apparent decrease in the evoked overflow of norepinephrine (NE) due to a presumed deactivation of NE by nitric oxide (NO), despite increased sympathetic nerve activity. The net effect of these offsetting system was no change in basal or the evoked increase in perfusion pressure (sympathetic tone). It is concluded that differences in NPY and NE transmission act as an important compensatory mechanism preventing dramatic changes in arterial pressure when sympathetic nerve activity is high during cold stress.