Dynamics of bridge-loop transformation in a membrane with mixed monolayer/bilayer structures.

Instead of forming a typical bilayer or monolayer membrane, both the bridge (I-shape) and loop (U-shape) conformations coexist in the planar membranes formed by ABA triblock copolymers in a selective solvent. The non-equilibrium and equilibrium relaxation dynamics of polymer conformations are monitored. The non-equilibrium relaxation time depends on the initial composition and increases with an increase in the immiscibility between A and B blocks. The equilibrium composition of the loop-shape polymer is independent of the initial composition and A-B immiscibility. However, the extent of equilibrium composition fluctuations subsides as the A and B blocks become highly incompatible. The influences of the A-B immiscibility on the geometrical, mechanical, and transport properties of the membrane have also been investigated. As the immiscibility increases, the overall membrane thickness and the B block layer thickness (h) increase because of the increment in the molecular packing density. As a result, both the stretching (KA) and bending (KB) moduli grow significantly with the increasing A-B immiscibility. Consistent with the case of typical membranes, the ratio KB/KAh2 = 2 × 10-3 is a constant. Although the lateral diffusivity of polymers is insensitive to immiscibility, the membrane permeability decreases substantially as the A-B immiscibility is increased.

Unraveling implicit human behavioral effects on dynamic characteristics of Covid-19 daily infection rates in Taiwan.

We investigate the dynamic characteristics of Covid-19 daily infection rates in Taiwan during its initial surge period, focusing on 79 districts within the seven largest cities. By employing computational techniques, we extract 18 features from each district-specific curve, transforming unstructured data into structured data. Our analysis reveals distinct patterns of asymmetric growth and decline among the curves. Utilizing theoretical information measurements such as conditional entropy and mutual information, we identify major factors of order-1 and order-2 that influence the peak value and curvature at the peak of the curves, crucial features characterizing the infection rates. Additionally, we examine the impact of geographic and socioeconomic factors on the curves by encoding each of the 79 districts with two binary characteristics: North-vs-South and Urban-vs-Suburban. Furthermore, leveraging this data-driven understanding at the district level, we explore the fine-scale behavioral effects on disease spread by examining the similarity among 96 age-group-specific curves within urban districts of Taipei and suburban districts of New Taipei City, which collectively represent a substantial portion of the nation's population. Our findings highlight the implicit influence of human behaviors related to living, traveling, and working on the dynamics of Covid-19 transmission in Taiwan.

Degradation of the internal elastic laminae in vein grafts of rats with aortocaval fistulae: potential impact on graft vasculopathy.

The internal elastic lamina (IEL) of vein grafts may be modified when exposed to arterialized hemodynamics. We investigated changes of the IEL in the inferior vena cava (IVC) of rats with aortocaval fistulae (ACF). In the IVC of ACF rats, both a markedly increased flow velocity and a mildly increased pressure were demonstrated. In the lower segment where hemodynamic changes were prominent, neointimal hyperplasia was prominently found. The IEL of the IVC in sham-operated rats, observed by confocal microscopy, was composed of parallel elastic fibers. In ACF rats, the IEL degenerated progressively after surgery. The elastic fibers were stretched and gradually became sparse, a change that was more prominent in the lower segment. Eight weeks after surgery, the IEL hardly existed in some areas of the lower segment. Electron microscopy revealed decreased densities and diameters of elastic fibers. Reverse transcriptase-polymerase chain reaction analysis revealed an up-regulation of potent elastases, cathepsins K and S, and matrix metalloproteinase-2 in the IVC of ACF rats. Results of immunohistochemical studies localized cathepsin expression predominantly to the luminal endothelium lining the IEL, suggesting involvement of elastinolysis in the degradation of the IEL. We demonstrated the degradation of the IEL in the vein graft of ACF rats, especially in the segment exposed to prominent hemodynamic changes. IEL degradation may contribute to the development of neointimal hyperplasia in vein grafts.

[Expression of TGF-beta and hepatocyte growth factor in kidney tissues of children with primary focal segmental glomerular sclerosis].

OBJECTIVE: To study the expression of transforming growth factor-beta (TGF-beta) and hepatocyte growth factor (HGF) in kidney tissues of children with primary focal segmental glomerular sclerosis (FSGS) and the possible role of the two growth factors in the development of FSGS. METHODS: Kidney specimens were obtained from 33 children with primary FSGS and 7 children with isolated haematuria but without FSGS (control group). Of the 33 children with primary FSGS, 6 children had no renal tubule interstitial pathological damage (Experimental I group) and 27 children had renal tubule interstitial pathological damage (Experimental II group). Expression of TGF-beta and HGF in kidney tissues was ascertained by the immunohistochemical method. RESULTS: TGF-beta and HGF were expressed in the three groups, but there were significant differences among the three groups. The expression of TGF-beta and HGF in the two experiment groups increased significantly compared with that in the control group. The Experimental II group had increased TGF-beta expression but a significantly decreased HGF expression compared with the Experimental I group. The index of tubule interstitial pathological changes was positively correlated with the TGF-beta expression (r=0.763, P<0.01), but negatively correlated with the HGF expression (r=-0.461, P<0.05) in the Experimental II group. There was a negative correlation between TGF-beta and HGF expression in children with primary FSGS (r=-0.425, P<0.05). CONCLUSIONS: The expression of TGF-beta and HGF in kidney tissues is increased in children with primary FSGS. TGF-beta might be a fibrogenic factor and HGF might be an anti-fibrotic factor in the kidney in primary FSGS.

The Role of Sharp Dissection in Nipple-Sparing Mastectomy: A Safe Procedure with No Necrosis of the Nipple-Areolar Complex.

BACKGROUND: Nipple-sparing mastectomy (NSM) is becoming increasingly accepted as a treatment for breast disease; however, nipple-areolar complex (NAC) necrosis, a frequent severe postoperative complication, inhibits the popularity of this procedure. This study reports the technical aspects and short-term postoperative outcomes of NSM. METHODS: A single-center, retrospective review of 110 patients treated with NSM at our institution from November 2015 to September 2018 was performed. The primary outcome was the incidence of NAC necrosis. RESULTS: A total of 130 NSMs performed on 110 patients were included in our study. Median patient age was 42 years. We performed a sharp dissection by using a scalpel, raising 3-5 mm thick flaps, and continuing onto the undersurface of the NAC. None of the 110 patients appeared to have NAC necrosis or mastectomy skin flap necrosis. However, discoloration or ischemia of the NAC with eschar formation presented between postoperative days 3 and 7 in six nipples; four nipples were ischemic, and two were discolored. No infection was detected in any of the 110 patients. All NACs were intact after an average follow-up of 30 months, and no local or systemic recurrence was detected in those breast cancer cases. CONCLUSION: NSM can be safely performed in properly selected patients. Nipple necrosis was avoided using a special surgical technique, and other complications occurred at an acceptable rate.

Strongly Coupled Tin-Halide Perovskites to Modulate Light Emission: Tunable 550-640 nm Light Emission (FWHM 36-80 nm) with a Quantum Yield of up to 6.4.

Colloidal perovskite quantum dots represent one of the most promising materials for applications in solar cells and photoluminescences. These devices require a low density of crystal defects and a high yield of photogenerated carriers, which are difficult to realize in tin-halide perovskite because of the intrinsic instability of tin during nucleation. Here, an enhancement in the luminescent property of tin-halide perovskite nanoplates (TPNPs) that are composed of strongly coupled layered structures with the chemical formula of PEA2 SnX4 (PEA = C6 H5 (CH2 )2 NH3 , X = Br, I) is reported. TPNPs (X = I) show an emission at a wavelength of 640 nm, with high quantum yield of 6.40 ± 0.14% and full width at half maximum (FWHM) as small as 36 nm. The presence of aliphatic carboxylic acid is found to play a key role in reducing the tin perovskite defect density, which significantly improves the emission intensity and stability of TPNPs. Upon mixing iodo- and bromo- precursors, the emission wavelength is successfully tuned from 640 nm (PEA2 SnI4 ) to 550 nm (PEA2 SnBr4 ), with a corresponding emission quantum yield and FWHM of 0.16-6.40% and 36-80 nm, respectively. The results demonstrate a major advance for the emission yield and tunability of tin-halide perovskites.

Comparative Efficacy and Safety of Nine Anti-Platelet Therapies for Patients with Ischemic Stroke or Transient Ischemic Attack: a Mixed Treatment Comparisons.

Anti-platelet treatments, an effective anti-thrombotic therapy, are widely used in non-cardioembolic ischemic stroke or transient ischemic attack (TIA), including aspirin, cilostazol, clopidogrel, and other mono or dual therapies, while the optimal choice remains uncertain. All the literatures of 38 eligible randomized control trials were searched in PubMed, Embase, and China National Knowledge Internet (CNKI) without language limitation. And, nine anti-platelet therapies were assessed, including aspirin, clopidogrel, cilostazol, ticlopidine, triflusal, terutroban, sarpogrelate, dipyridamole plus aspirin, and clopidogrel plus aspirin. Additionally, we extract data of composite vascular events, major bleeding, ischemic stroke, intracranial hemorrhage, and all-cause death, as indicators of efficacy and safety. And among them, composite vascular events were the primary outcome. The binary outcomes were expressed as odds ratios (ORs) with corresponding 95 % confidence intervals (CIs). Both traditional meta-analysis and network meta-analysis were performed. Besides, for each outcome, the rank order was applied to reflect the superiority of every therapy compared with others, using the surface under the cumulative ranking curve (SUCRA). A cluster analysis was also conducted. Through the network meta-analysis, the synthesized data shows that cilostazol performed best on composite vascular events compared with placebo (OR = 0.62, 95 % CI 0.46-0.83) and aspirin (OR = 0.71, 95 % CI 0.53-0.95). In terms of ischemic stroke, clopidogrel plus aspirin seems the optimal, and it has significant difference between placebo (OR = 0.53, 95 % CI 0.35-0.74) and aspirin (OR = 0.75, 95 % CI 0.61-0.95). Meanwhile, cilostazol is also the first rank in major bleeding, especially when it is in contrast to aspirin (OR = 0.13, 95 % CI 0.02-0.70) and clopidogrel plus aspirin (OR = 0.09, 95 % CI 0.01-0.50). There is no significant difference among these nine treatments and placebo, as to all-cause death and intracranial hemorrhage. According to the cluster analysis, cilostazol can be the best choice with comprehensive assessment of composite vascular events, ischemic stroke and major bleeding. Based on this network meta-analysis, cilostazol was recommended as the optimal choice with good performance in both efficacy and safety for patient with ischemic stroke or TIA among nine anti-platelet therapies.

Genetic diversity of small eukaryotes from the coastal waters of Nansha Islands in China.

Population structures and genetic diversity of the small eukaryotic plankton from the coastal waters of the Nansha Islands in China were investigated. Two genes libraries using 18S rDNA of the marine small eukaryotes were constituted, and 323 clones were identified within alveolates (more than 43%), acanthareas, viridiplantaes, and stramenopiles. Many novel clones were detected in the two libraries, including two groups of alveolates and two clades related to both acanthareas and polycystineas. Several sequences unrelated to any other known eukaryotes may represent early branches in the phylogenetic tree. Our results reveal that there is a high diversity and abundance of small eukaryotes in the marine regions of China.

Phyllanthus urinaria induces the Fas receptor/ligand expression and ceramide-mediated apoptosis in HL-60 cells.

Phyllanthus urinaria (P. urinaria), a widely used herb medicine, was tested for the anticancer effect on human myeloid leukemia cells in this study. The water extract of P. urinaria induced the apoptosis of HL-60 cells as demonstrated by morphological change, DNA fragmentation and increased caspase-3 activity. However, normal human peripheral mononuclear cells remained viable under the same treatment. The P. urinaria-induced apoptosis of HL-60 cells was associated with the increased Bax gene expression and decreased Bcl-2 gene expression. In addition, the gene expressions of Fas receptor and Fas ligand, but not p53, were also induced in HL-60 cells dose- and time-dependently. The inhibitor of ceramide synthase, fumonisin B1, completely suppressed the apoptosis induced by P. urinaria and this inhibitory effect of fumonisin B1 could be eliminated by the addition of ceramide. It indicated that the activity of ceramide synthase is critical for the P. urinaria-induced apoptosis in HL-60 cells. The P. urinaria-induced apoptosis in HL-60 cells is mediated through a ceramide-related pathway.