Strukturuntersuchungen von Tensidaggregaten in den Poren von mesoporösen SBA-15 Materialien mittels SANS

In dieser Arbeit wurden die Struktur und die Gestalt der Aggregaten von nicht-ionischen und kationischen Tensiden in den Poren vom mesoporösen Silikat SBA-15 durch Neutronen Kleinwinkelstreuung untersucht. Aufgrund der unterschiedlichen Wechselwirkungsstärken von Kopfgruppen mit der Porenwand und von der hydrophoben Anziehung der Alkylketten untereinander, wurden unterschiedliche Streukurven für jeweiligen SBA-15 Proben beobachtet, die mit verschiedenen Typen von Tensiden und bei verschiedenen Beladungen adsorbiert waren. SBA-15 Materialien weisen 2D hexagonale Anordnung von zylindrischen Poren auf, wobei die Porenweite, die spezifische Oberfläche, das Porenvolumen und die Gitterkonstante mittels N2-adsorption und SAXS charakterisiert werden. Für einige Tenside waren vor der Neutronstreumessung Adsorptionsmessung erforderlich. Die Neutron-Streukurven von den stark adsorbierenden nicht-ionischen Tensiden C10E5 und C12E5 weisen eine Überlagerung von diffuser Kleinwinkelstreuung mit Bragg-Reflexen auf und konnten mittels einer passenden Modellfunktion (modifizierte Teubner-Strey Funktion) gefittet werden. Die Ergebnisse dieser Analyse liefern den mittleren Abstand zwischen Tensidaggregaten d, die Korrelationslänge ξ, und die mittlere Dicke der Tensidschicht t. Bei zunehmender Beladung von Tensid wird d kleiner, wobei ξ und t größer werden. Dies besagt, dass die Tensidmoleküle bei der kleinen Beladung zunächst in einem größeren Abstand isoliert aggregieren (Oberflächenmizelle), mit zunehmender Beladung die Abstände zwischen den Aggregaten kleiner und diese Aggregate dann bei der höchsten Beladung zu einer Tensidschicht vernetzt werden. Für die SBA-15 Proben mit dem schwach adsorbierenden C10G2 wurde der Formfaktor der Kugelmizellen angewendet, um die Streudaten zu fitten. Die mit C10G1 adsorbierte SBA-15 Probe zeigt jedoch eine Überlagerung von einer Streukurve der zylindrischen Mizellen und (10) Bragg-Peak der 2D hexagonalen Anordnung von Mesoporen. Die Streukurven von den mit kationischen Tensiden adsorbierten SBA-15 Proben konnten mit der modifizierten Teubner-Strey Modellfunktion nicht analysiert werden. Der Grund dafür besteht darin, dass die Streukurven nur bei den höchsten zwei Beladungen 4 führende Bragg-Peaks zeigen, wodurch die Fit-Analyse sehr eingeschränkt möglich ist. Die Ergebnisse der TGA Messungen konnten dazu verwendet werden, um die Plateauwerte der Adsorptionsmessungen zu vergleichen, so dass tatsächliche Plateauwerte der Adsorption in der vorliegenden Arbeit qualitativ überprüft werden konnten.In this work the structure and the shape of the aggregates of nonionic and cationic surfactants in the pores of mesoporous silica SBA-15 were investigated by neutron scattering. Due to the different strengths of interaction of the head groups with the pore wall and the hydrophobic attraction between the alkyl chains, different scattering curves for the respective SBA-15 samples which were adsorbed with various types of surfactants and at different loadings were observed. SBA-15 materials show 2D hexagonal arrangement of cylindrical pores, where the pore size, the specific surface, the pore volume and the lattice constant were characterized by N2-adsorption and SAXS. For some surfactants, adsorption measurements were required prior to the neutron scattering measurement. The neutron scattering curves of the strongly adsorbing nonionic surfactants C10E5 and C12E5 show a superposition of diffuse small-angle scattering with Bragg reflections and could be fitted using a suitable model function (modified Teubner-Strey function). The results of this analysis provide the mean distance between surfactant aggregates d, the correlation length ξ, and the average thickness of the surfactant layer t. With increasing surfactant loading, d becomes smaller, while ξ and t become greater. This says that at small loading the surfactant molecules aggregate at first in a larger distance (isolated surface micelles), with increasing surfactant amount the distances between the aggregates become small and these aggregates are then interconnected to a patch-like surfactant layer at the highest loading. For the SBA-15 samples adsorbed by weakly adsorbing C10G2 the form factor of spherical micelles was applied in order to fit the scattering data. On the other hand, the SBA-15 sample with adsorbed C10G1 shows a superposition of a scattering curve of the cylindrical micelles and (10) Bragg peak of the 2D hexagonal arrangement of the mesopores. The scattering curves of SBA-15 samples with adsorbed cationic surfactants could not be analyzed with the modified Teubner-Strey model function. The reason is that the scattering curves show only the two highest loadings leading four Bragg peaks, making the Fit-analysis very limited. The results of the TGA measurements could be used to compare the plateau values of the adsorption measurements, which allow qualitative check of the actual plateau values of adsorption in the present work

Effects of education on low-phosphate diet and phosphate binder intake to control serum phosphate among maintenance hemodialysis patients: A randomized controlled trial.

Background:For phosphate control, patient education is essential due to the limited clearance of phosphate by dialysis. However, well-designed randomized controlled trials about dietary and phosphate binder education have been scarce. Methods:We enrolled maintenance hemodialysis patients and randomized them into an education group (n = 48) or a control group (n = 22). We assessed the patients' drug compliance and their knowledge about the phosphate binder using a questionnaire. Results:The primary goal was to increase the number of patients who reached a calcium-phosphorus product of lower than 55. In the education group, 36 (75.0%) patients achieved the primary goal, as compared with 16 (72.7%) in the control group (P = 0.430). The education increased the proportion of patients who properly took the phosphate binder (22.9% vs. 3.5%, P = 0.087), but not to statistical significance. Education did not affect the amount of dietary phosphate intake per body weight (education vs. control: -1.18 ± 3.54 vs. -0.88 ± 2.04 mg/kg, P = 0.851). However, the dietary phosphate-to-protein ratio tended to be lower in the education group (-0.64 ± 2.04 vs. 0.65 ± 3.55, P = 0.193). The education on phosphate restriction affected neither the Patient-Generated Subjective Global Assessment score (0.17 ± 4.58 vs. -0.86 ± 3.86, P = 0.363) nor the level of dietary protein intake (-0.03 ± 0.33 vs. -0.09 ± 0.18, P = 0.569). Conclusion:Education did not affect the calcium-phosphate product. Education on the proper timing of phosphate binder intake and the dietary phosphate-to-protein ratio showed marginal efficacy

Full-Spectrum Photonic Pigments with Non-iridescent Structural Colors through Colloidal Assembly

Structurally colored materials could potentially replace dyes and pigments in many applications, but it is challenging to fabricate structural colors that mimic the appearance of absorbing pigments. We demonstrate the microfluidic fabrication of “photonic pigments” consisting of microcapsules containing dense amorphous packings of core–shell colloidal particles. These microcapsules show non-iridescent structural colors that are independent of viewing angle, a critical requirement for applications such as displays or coatings. We show that the design of the microcapsules facilitates the suppression of incoherent and multiple scattering, enabling the fabrication of photonic pigments with colors spanning the visible spectrum. Our findings should provide new insights into the design and synthesis of materials with structural colors.Engineering and Applied Science

Reappraisal of Plasmapheresis as a Supportive Measure in a Patient with Hepatic Failure after Major Hepatectomy

Major resection of cirrhotic livers can result in hepatic failure, but no supportive treatment has been found to be generally effective. We successfully treated a 63-year-old woman with post-hepatectomy liver failure with plasmapheresis. Following right hepatectomy, the initial postoperative recovery of liver function was favorable, except for ascites. One month later, however, the amount of drained ascites increased up to 2 l/day. In addition, serum cholesterol concentration gradually decreased to around 30 mg/dl, and serum total bilirubin rose to 11.1 mg/dl. Plasmapheresis was performed, and after just 2 sessions, serum cholesterol level was rapidly corrected and prothrombin time was restored. After 3 sessions of plasmapheresis, the usual rebound rise of serum bilirubin disappeared, and the amount of ascites drained also decreased slowly. The patient underwent a total of 5 sessions of plasmapheresis over 2 weeks, after which liver function improved slowly, and she was finally discharged 72 days after liver resection. Mild ascites requiring diuretic therapy persisted over 3 months. She is doing well to date 10 months after liver resection without tumor recurrence or hepatic decompensation. This limited experience suggests that plasmapheresis can be a useful liver support for post-hepatectomy liver failure

Effects of Huang Bai (Phellodendri Cortex) and Three Other Herbs on GnRH and GH Levels in GT1–7 and GH3 Cells

The present study was to evaluate the effects of Huang Bai, Zhi Mu, Mai Ya, and Xia Ku Cao on hormone using the GT1–7 and GH3 cells. The GT1–7 and GH3 cell lines were incubated with DW; DMSO; and 30, 100, or 300 μg/mL of one of the four extract solutions in serum-free media for 24 hours. The MTT assay was performed to determine the cytotoxicity of the four herbs. The GT1–7 and GH3 cells were incubated in DW, estradiol (GT1–7 only), or noncytotoxic herb solutions in serum-free medium for 24 hours. A quantitative RT-PCR and western blot were performed to measure the GnRH expression in GT1–7 cells and GH expression in GH3 cells. Huang Bai, Zhi Mu, Xia Ku Cao, and Mai Ya inhibited the GnRH mRNA expression in GT1–7 cells, whereas Huang Bai enhanced GH mRNA expression in GH3 cells. Additionally, Xia Ku Cao inhibited GnRH protein expression in GT1–7 cells and Huang Bai promoted GH protein expression in GH3 cells. The findings suggest that Huang Bai can delay puberty by inhibiting GnRH synthesis in the hypothalamus while also accelerating growth by promoting GH synthesis and secretion in the pituitary

Clinical Relevance of Pain Patterns in Osteoporotic Vertebral Compression Fractures

Few studies have been conducted to explain the pain patterns resulting from osteoporotic vertebral compression fractures (OVCF). We analyzed pain patterns to elucidate the pain mechanism and to provide initial guide for the management of OVCFs. Sixty-four patients underwent percutaneous vertebroplasty (N=55) or kyphoplasty (N=9). Three pain patterns were formulized to classify pains due to OVCFs: midline paravertebral (Type A), diffuse paravertebral (Type B), and remote lumbosacral pains (Type C). The degree of compression was measured using scale of deformity index, kyphosis rate, and kyphosis angle. Numerical rating scores were serially measured to determine the postoperative outcomes. As vertebral body height (VBH) decreased, paravertebral pain became more enlarged and extended anteriorly (p<0.05). Type A and B patterns significantly showed the reverse relationship with deformity index (p<0.05), yet Type C pattern was not affected by deformity index. Postoperative pain severity was significantly improved (p<0.05), and patients with a limited pain distribution showed a more favorable outcome (p<0.05). The improvement was closely related with the restoration of VBH, but not with kyphosis rate or angle. Thus, pain pattern study is useful not only as a guide in decision making for the management of patients with OVCF, but also in predicting the treatment outcome

Alpha-2-Macroglobulin as a New Promising Biomarker Improving the Diagnostic Sensitivity of Bovine Paratuberculosis

Johne&apos;s disease (JD) is a chronic granulomatous enteritis of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP), which induces persistent diarrhea and cachexia. JD causes huge economic losses to the dairy industry due to reduced milk production and premature culling. Infected animals excrete MAP via feces during the prolonged subclinical stage without exhibiting any clinical signs. Therefore, accurate detection of subclinical stage animals is crucial for successful eradication of JD in the herd. In the current study, we analyzed serum samples of MAP-infected and non-infected cattle to identify potential biomarker candidates. First, we identified 12 differentially expressed serum proteins in subclinical and clinical shedder groups compared to the healthy control group. Second, we conducted ELISA for three selected biomarkers (alpha-2-macroglobulin (A2M), alpha-1-beta glycoprotein, and transthyretin) and compared their diagnostic performance with that of two commercial ELISA diagnostic kits. Serum A2M levels were significantly higher in the MAP-exposed, subclinical shedder, subclinical non-shedder, and clinical shedder groups than in the healthy control group, suggesting its possible use as a diagnostic biomarker for MAP infection. Furthermore, A2M demonstrated a sensitivity of 90.4%, and a specificity of 100% while the two commercial ELISA kits demonstrated a sensitivity of 67.83 and 73.04% and a specificity of 100%, respectively. In conclusion, our results suggest that measuring A2M by ELISA can be used as a diagnostic tool to detect MAP infection, considerably improving the detection rate of subclinical shedders and MAP-exposed animals that are undetectable using current diagnostic tools