Sensing surface morphology of biofibers by decorating spider silk and cellulosic filaments with nematic microdroplets

Probing the surface morphology of microthin fibers such as naturally occurring biofibers is essential for understanding their structural properties, biological function, and mechanical performance. The state-of-the-art methods for studying the surfaces of biofibers are atomic force microscopy imaging and scanning electron microscopy, which well characterize surface geometry of the fibers but provide little information on the local interaction potential of the fibers with the surrounding material. In contrast, complex nematic fluids respond very well to external fields and change their optical properties upon such stimuli. Here we demonstrate that liquid crystal droplets deposited on microthin biofibers—including spider silk and cellulosic fibers—reveal characteristics of the fibers’ surface, performing as simple but sensitive surface sensors. By combining experiments and numerical modeling, different types of fibers are identified through the fiber-to-nematic droplet interactions, including perpendicular and axial or helicoidal planar molecular alignment. Spider silks align nematic molecules parallel to fibers or perpendicular to them, whereas cellulose aligns the molecules unidirectionally or helicoidally along the fibers, indicating notably different surface interactions. The nematic droplets as sensors thus directly reveal chirality of cellulosic fibers. Different fiber entanglements can be identified by depositing droplets exactly at the fiber crossings. More generally, the presented method can be used as a simple but powerful approach for probing the surface properties of small-size bioobjects, opening a route to their precise characterization.Natural microfilaments produced by plants, insects, or spiders are fascinating materials not just because of their specific properties such as wear resistance, elasticity, tensile strength, and toughness (1–5) but also because of their microorganization (6–9). Their macroscopic properties can match properties of materials like kevlar but are at the same time biocompatible and biodegradable (10). These fascinating macroscopic properties actually originate from bulk and surface properties of the fibers (1). The chemical composition of the threads combined with their morphology determines the final properties of the material (11–13). The mechanical properties of the spider fibers are determined by the existence of a lyotropic liquid crystalline phase, from which the threads are drawn (14). Such silks are known to include nanoscale networks of defects and cavities that yield surface structures notably dependent on the spider species (3). These differences do not affect much the mechanical performance of the fibers (1, 3, 5). From a technological perspective, many attempts have been made to reproduce these natural bionetworks (15–17). In fact cellulose-based fibers with few micrometers of diameter, produced by electrospinning, can also acquire different morphologies depending upon the processing conditions, giving diverse features of the final threads and mats (18). Therefore, probing the surface structure of the microfibers is crucial for a complete understanding of their individual and interthreaded properties.From another perspective, nematic complex fluids are materials which are inherently responsive to diverse external stimuli, notably including diverse surface interactions which in the literature are known as the surface anchoring (19). Being effectively elastic materials, the orientational order of nematics responds on long, typically micrometer scales (20–22), which results in a spatially varying birefringence that can be optically detected (23). Recently, it was demonstrated that glass fibers induce numerous defects in a well-aligned nematic liquid crystal cell and thus provide a simple illustration of topological phenomena (24). It is also known that liquid crystal droplets can considerably change their structure by the action of otherwise imperceptibly small external stimuli (21). Pierced nematic and chiral nematic droplets develop defects that can be controlled by the liquid crystal elasticity, chirality, and surface boundary conditions (25, 26) indicating exceptional sensitivity. Therefore, to generalize, putting nematics into contact with diverse surfaces (18, 27) can be used as a simple but very powerful technique to detect the surface properties of microobjects such as biological fibers.In this paper we demonstrate the surface morphology sensing of biorelevant fibers, including spider silk and cellulosic microfibers, by nematic droplets that are sprayed onto the fibers. Specifically, we explore the chiral and achiral nature of the fiber’s surface and the in-plane or perpendicular alignment fields the fibers impose on the nematic. Droplets with degenerate in-plane and perpendicular alignment of the nematic at their free surfaces are explored, combining experiments and numerical modeling, to allow for tuning of the sensing precision. Further, the entanglement sites of the fiber webs are explored, with the droplets deposited at the sites clearly revealing contact, noncontact, and entangled morphologies.     

Comparison of intragastric pressure between endotracheal tube and supraglottic airway devices in laparoscopic hepatectomy: A randomized,controlled, non-inferiority study

Background:Supraglottic airway (SGA) devices do not definitively protect the airway from regurgitation of gastric contents. Increased gastric pressure and long operation time are associated with development of complications such as aspiration pneumonia. The aim of this study was to compare intragastric pressure between second-generation SGA and endotracheal tube (ETT) devices during long-duration laparoscopic hepatectomy.Methods:A total of 66 patients was randomly assigned to 2 groups; 33 patients each in the ETT and SGA groups. Intragastric pressure was continuously measured via a gastric drainage tube with a three-way stopcock connected to the pressure monitoring device. Normal saline was added to the end of the gastric drainage tube at each operation time point.Results:Intragastric pressure during pneumoperitoneum was no different between the 2 groups (P = .146) or over time (P = .094). The mean (standard deviation [SD]) pH of the SGA tip measured after operation was 6.7 (0.4), and a pH <4 was not observed. Relative risk of postoperative complications was significantly higher in the ETT group relative to the SGA group (sore throat, 5.5; cough,13.0).Conclusions:Use of SGA devices does not further increase intragastric pressure, even during prolonged upper abdominal laparoscopic surgery. Also, the frequency of postoperative sore throat and cough was significantly lower when the second-generation SGA device was used.     

Eupartoium makinoi suppresses lipopolysaccharide-induced inducible nitric oxide synthase and cyclooxygenase-2 expression

Inflammation is involved in numerous diseases including cancer. Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) play important roles in the development of certain inflammatory diseases. Eupatorium makinoi, which belongs to a family of Asteraceae plants, is used medicinally in East Asia. We investigated the effects of an ethanol extract of E. makinoi (EEM) on nuclear factor-kappa B (NF-κB) activation and the expression of iNOS and COX-2 with lipopolysaccharide (TLR4 agonist) in murine macrophages. EEM suppressed NF-κB activation and iNOS and COX-2 expression induced by LPS. These results suggest that EEM may regulate TLR4 signalling pathways and this may be a useful strategy for anti-inflammatory therapies.     

Cerebral Angiographic Findings of Cosmetic Facial Filler-related Ophthalmic and Retinal Artery Occlusion

Cosmetic facial filler-related ophthalmic artery occlusion is rare but is a devastating complication, while the exact pathophysiology is still elusive. Cerebral angiography provides more detailed information on blood flow of ophthalmic artery as well as surrounding orbital area which cannot be covered by fundus fluorescein angiography. This study aimed to evaluate cerebral angiographic features of cosmetic facial filler-related ophthalmic artery occlusion patients. We retrospectively reviewed cerebral angiography of 7 patients (4 hyaluronic acid [HA] and 3 autologous fat-injected cases) showing ophthalmic artery and its branches occlusion after cosmetic facial filler injections, and underwent intra-arterial thrombolysis. On selective ophthalmic artery angiograms, all fat-injected patients showed a large filling defect on the proximal ophthalmic artery, whereas the HA-injected patients showed occlusion of the distal branches of the ophthalmic artery. Three HA-injected patients revealed diminished distal runoff of the internal maxillary and facial arteries, which clinically corresponded with skin necrosis. However, all fat-injected patients and one HA-injected patient who were immediately treated with subcutaneous hyaluronidase injection showed preserved distal runoff of the internal maxillary and facial arteries and mild skin problems. The size difference between injected materials seems to be associated with different angiographic findings. Autologous fat is more prone to obstruct proximal part of ophthalmic artery, whereas HA obstructs distal branches. In addition, hydrophilic and volume-expansion property of HA might exacerbate blood flow on injected area, which is also related to skin necrosis. Intra-arterial thrombolysis has a limited role in reconstituting blood flow or regaining vision in cosmetic facial filler-associated ophthalmic artery occlusions.     

Human Urine-derived Stem Cells Seeded Surface Modified Composite Scaffold Grafts for Bladder Reconstruction in a Rat Model

We conducted this study to investigate the synergistic effect of human urine-derived stem cells (USCs) and surface modified composite scaffold for bladder reconstruction in a rat model. The composite scaffold (Polycaprolactone/Pluronic F127/3 wt% bladder submucosa matrix) was fabricated using an immersion precipitation method, and heparin was immobilized on the surface via covalent conjugation. Basic fibroblast growth factor (bFGF) was loaded onto the heparin-immobilized scaffold by a simple dipping method. In maximal bladder capacity and compliance analysis at 8 weeks post operation, the USCs-scaffold^heparin-bFGF group showed significant functional improvement (2.34 ± 0.25 mL and 55.09 ± 11.81 µL/cm H₂O) compared to the other groups (2.60 ± 0.23 mL and 56.14 ± 9.00 µL/cm H₂O for the control group, 1.46 ± 0.18 mL and 34.27 ± 4.42 µL/cm H₂O for the partial cystectomy group, 1.76 ± 0.22 mL and 35.62 ± 6.69 µL/cm H₂O for the scaffold group, and 1.92 ± 0.29 mL and 40.74 ± 7.88 µL/cm H₂O for the scaffold^heparin-bFGF group, respectively). In histological and immunohistochemical analysis, the USC-scaffold^heparin-bFGF group showed pronounced, well-differentiated, and organized smooth muscle bundle formation, a multi-layered and pan-cytokeratin-positive urothelium, and high condensation of submucosal area. The USCs seeded scaffold^heparin-bFGF exhibits significantly increased bladder capacity, compliance, regeneration of smooth muscle tissue, multi-layered urothelium, and condensed submucosa layers at the in vivo study.     

May maternal anti-mullerian hormone levels predict adverse maternal and perinatal outcomes in preeclampsia?

Background: Prediction of preeclampsia and adverse maternal and perinatal outcomes with biomarkers has been proposed previously. Anti-mullerian hormone (AMH) is a growth factor, which is primarily responsible of the regression of the mullerian duct, but also used to predict ovarian reserve and decreases with age similar to the fertility.

Aim: To evaluate the predictive role of maternal anti-mullerian hormone (mAMH) in adverse maternal and perinatal outcomes in preeclampsia.

Methods: This prospective case-control study was conducted at current high-risk pregnancy department in a tertiary research hospital and 45 cases with preeclampsia classified as study group and 42 as control group. Data collected and evaluated were; age, body mass index (BMI), marriage duration (MD), gestational weeks (GW), gravidity, parity, mode of delivery, birth weight, newborn Apgar score, newborn gender, maternal complication, perinatal outcome, some laboratory parameters and mAMH. The association between mAMH levels and maternal and fetal outcomes were evaluated.

Results: There were no statistically significant differences between groups in terms of age, BMI, MD, gravidity, parity and newborn gender (p?>?0.05). GW, vaginal delivery, birth weight, newborn Apgar score, were statistically significantly lower in preeclamptic patients when compared with non-preeclamptic patients (p?<?0.001). Adverse maternal and perinatal outcomes were statistically significantly higher in the study group (p?<?0.001). The laboratory values [alanine transaminase (ALT), aspartate transaminase (AST), blood urea nitrogen (BUN), creatinine, lactic dehydrogenase (LDH), uric acid and fibrinogen) were statistically significantly lower in the control group (p?<?0.001). The mAMH level was significantly lower in the preeclamptic group (p: 0.035). There was no correlation between mAMH levels and demographic and clinical parameters. The area under the ROC curve (AUC) was 0.590 and the cut-off value was 0.365?ng/ml with sensitivity of 67.4% and specificity of 47.1% for mAMH. Logistic regression analysis showed a statistically insignificance between mAMH and maternal complication and perinatal outcome (p: 0.149).

Conclusion: According to this study, mAMH level was lower in preeclamptic patients than in normal pregnants, and is found to be a discriminative factor with low sensitivity and specificity. There was no relationship between mAMH and adverse maternal and perinatal outcomes. Further randomized controlled studies with more participants are needed to evaluate the accurate effects of mAMH levels on preeclampsia and should increase the power of mAMH levels in predicting the preeclampsia.     

Evolution and Progression of Spondylodiskitis: A Case Presentation

Pyogenic infection of the spinal column is a relatively rare condition. Spondylodiskitis is characterized by infection of the intervertebral disk and the adjacent vertebrae. Diagnosis is often delayed because the symptoms are often nonspecific and also because of the high incidence of nonspecific low back pain in the general population. We report the case of a 42-year-old woman who developed low back pain secondary to spondylodiskitis. Her diagnosis was delayed because of a lack of supporting findings on initial magnetic resonance imaging. The case highlights the clinical scenario in which maintaining a high index of suspicion may lead to follow-up imaging and an accurate diagnosis.

Predictive value of SYNTAX score II for clinical outcomes in cardiogenic shock underwent primary percutaneous coronary intervention; a pilot study

SYNTAX Score II (SSII) connects clinical variables with coronary anatomy. We investigated the prognostic value of SSII in patients with ST segment elevated myocardial infarction (STEMI) complicated with cardiogenic shock treated with primary percutaneous coronary intervention (PPCI). In this retrospective analysis, we evaluated the in-hospital prognostic impact of SSII on 492 patients with STEMI complicated with cardiogenic shock treated with PPCI. Patients were stratified by tertiles of SSII, in-hospital clinical outcomes were compared between those groups. In-hospital univariate analysis revealed higher rates of in-hospital death for patients with SSII in tertile 3, as compared to patients with SSII in tertile 1 (OR 17.4, 95% CI 10.0–30.2, p?<?0.001). After adjustment for confounding baseline variables, SSII in tertile 3 was associated with 6.2-fold hazard of in-hospital death (OR 6.2, 95% CI 2.6–14.1, p?<?0.001). SSII in patients with STEMI complicated with cardiogenic shock treated with PPCI provide an independent prognostic marker of in-hospital outcomes. Our data suggests SSII to be a simple, feasible and clinically applicable tool for rapid risk stratification in patients with STEMI complicated with cardiogenic shock treated with PPCI.