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Fluoxetine (FLX), used in the clinic to treat depression, is a well-known cationic amphiphilic antidepressant. However, there is a lack of research on the effect of FLX on the surface behavior of lipid monolayers under different surface pressures. In this study, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine/CHOL (DPPC/POPC/CHOL) monolayers were prepared via the Langmuir method, and FLX was added to these monolayers under various surface pressures. The effect of FLX on the surface behavior of DPPC/POPC/CHOL monolayers under various surface pressures was studied using a combination of surface pressure-area isotherms, compressibility modulus-surface pressure curves, and atomic force microscope (AFM). The results showed that the effect of FLX on the lipid monolayers was different under different surface pressures. The interaction between FLX and lipid molecules was weak under low surface pressures, and FLX could easily intercalate between the lipid molecules to inhibit monolayer phase transition. The interaction between FLX and lipid molecules was enhanced and FLX tended to self-aggregate to reduce the monolayer stability when the surface pressure was high. This study lays the foundation for further studies on the interaction between FLX and lipid monolayers.

The deposition of lignin and carbohydrates in different cells and morphologically distinct cell wall layers during the development of Calamus simplicifolius was investigated by combined microscopic techniques. Lignin autofluorescence images showed that protoxylem vessels were the first to differentiate among vascular elements. At the subcellular level, high spatial resolution Raman images revealed that the deposition of carbohydrates in fibers preceded that of lignin. Additionally, the lignin and carbohydrates concentration in the secondary wall (SW) varied among different cell types. The carbohydrates concentration in SW of fibers presented the highest level, which was much higher than that in vessels and parenchyma. High concentrations of lignin were most visible in the SW of vessels, followed by fibers, with the lowest amount visible in parenchyma. Within the morphologically distinct cell wall layers, the carbohydrates and lignin in fibers SW and cell corners deposited rapidly at the early stage from the 7th to the 10th internode, while the deposition rate decreased from the 10th to the 50th internode. The findings have substantial theoretical significance to understand the biosynthesis of rattan cell walls.

The permanent fixation is essential for the full industrialization of sandwich-compressed wood. In this study, sandwich-compressed wood was modified with superheated steam for compression fixation. Effects of superheated steam pressure on set-recovery were investigated. Changes in microstructure, chemical structure and cellulose crystalline structure of the compressed wood were analyzed, to clarify the reason and mechanism for sandwich compression fixation under superheated steam treatment. It was found that set-recovery of central-compressed wood was higher than that of surface-compressed wood. Effects of superheated steam treatment on set-recovery were statistically significant (P

Water exists in lignocellulosic materials throughout the whole process from the plant growth to raw materials processing and utilization. The fiber saturation point (FSP) is the inflection point of the physical and mechanical properties of lignocellulosic materials and has an important influence on their physical and mechanical properties. This paper investigates the FSP of Calamus simplicifolius by the low-field nuclear magnetic resonance (LF-NMR) method and two conventional methods including the saturated salt solution method and dynamic vapor sorption (DVS) method. The average FSP values determined by the LF-NMR method, the saturated salt solution method and the DVS method are 38.15%, 32.54% and 28.96%, respectively. The study showed that the FSP values determined by the LF-NMR method were higher than those determined by the two conventional methods. The two conventional methods are simple and cost-effective and are able to directly measure whether the rattan properties are changing with moisture content. From the thermodynamics standpoint, even within the ideal solution limit, free water is present at relative humidity (RH) of less than 100%. Therefore, extrapolation to 100% RH was not strictly correct. The amount of water in rattan in different states could be quantified by the LF-NMR method, and the FSP value was determined by the ratio of the measurements above and below the water melting point. Furthermore, the LF-NMR method is faster and non-destructive compared to the two conventional methods.

Density and moisture content (MC) are two of the most important wood performance indexes, which are highly correlated with many other physical and mechanical properties of wood. X-ray computed tomography (X-CT) technology was used to analyze the difference in the CT number of the heartwood and sapwood of Chinese white poplar (Populus tomentosa) and Masson pine (Pinus massoniana) under different MC. Additionally, the fitted models of CT number-density and CT number-MC were established and validated for the heartwood and sapwood of P. tomentosa and P. massoniana. The methodological improvement has been described in detail regarding the established models, which are contrasted and discussed with previous models. The results showed that the CT number-density fitted models of the heartwood and sapwood of P. tomentosa and P. massoniana adopted the linear model: $$ D = k \times H + b $$, where D is the density, H is the CT number, k is the slope, and b is the intercept. R2 values obtained in the validation models were all higher than 0.98, indicating that the CT number-density fitted models can reliably predict wood density. The CT number-MC fitted models for the heartwood and sapwood of P. tomentosa and P. massoniana adopted the logarithmic model: $$ M = \ln ((a + b \times H)^{100} ) $$, where M is the MC, H is the CT number, and a and b are the correlation coefficients in the model. R2 values obtained in the validation models were all higher than 0.95, indicating that this model is valid for the accurate prediction of wood MC. The fitted model parameters of heartwood and sapwood indicated that the X-CT technology was effective for identifying the difference in density and MC of heartwood and sapwood. Therefore, it is feasible to use non-destructive testing technology when studying density and MC of heartwood and sapwood based on X-CT technology. The study results provide reference data for the non-destructive testing of wood properties and reasonable utilization.

To assess the diagnostic performance of the H-score of 11β-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) in the histopathological diagnosis of adrenocortical tumors (ACT). We retrospectively evaluated 199 cases of ACT, of which 85 were diagnosed as aldosterone-producing adenoma (APA), 66 as cortisol-producing adenoma (CPA), 9 as aldosterone–cortisol co-secreting adenoma, 30 as nonhyperfunctioning adenoma, and 9 as adrenocortical carcinoma (ACC). Immunohistochemical staining was performed using anti-CYP11B1 and anti-CYP11B2 monoclonal antibodies. The staining was quantified by the McCarty’s H-score system. The diagnostic performance was assessed by the receiver operating characteristic curve (ROC). The H-score of CYP11B1 is highest in the CPA group and lowest in the ACC group. The H-score of CYP11B2 in the APA group is significantly higher than other ACT groups. The area under ROC (AUC) of an increased H-score of CYP11B2 (>65) for the diagnosis of APA was 0.971 (95%CI 0.937–0.990). The AUC of an increased H-score of CYP11B1 (>204) for the diagnosis of CPA was 0.725 (95%CI 0.658–0.786). The AUC of a decreased H-score of CYP11B1 (

Background The prevalence of primary aldosteronism concurrent with subclinical Cushing’s syndrome was higher than previously thought. Through analyzing a rare clinical case, we summarized the diagnosis and management of primary aldosteronism with subclinical Cushing’s syndrome. Case presentation A 54-year-old Chinese man of Han nationality was diagnosed as having primary aldosteronism with subclinical Cushing’s syndrome. An abdominal computed tomography scan revealed a mass in his left adrenal gland and a mass in his right adrenal gland. After finishing sequential adrenal venous sampling without adrenocorticotropic hormone, the result reminded us that the left and right nodules were responsible for hypercortisolism and aldosterone hypersecretion, respectively. Right and left adrenalectomy were performed successively. The pathological diagnosis was adrenocortical adenoma for both. Histological findings revealed that the right one had positive immunostaining for CYP11B2 and the left one had positive immunostaining for CYP11B1. The immunohistochemistry result helped us to confirm the diagnosis. Somatic KCNJ5 mutation (Leu168Arg) was found in the right tumor; there was no KCNJ5 mutation in the left adrenal tumor. Conclusions We suggest that patients with primary aldosteronism should have a low-dose overnight dexamethasone suppression test to screen for hypercortisolism. It can help avoid misdiagnoses and contribute to proper understanding of the adrenal vein sampling result. Making sure of the nidus of aldosterone and cortisol secretion is crucial for the therapy of patients with primary aldosteronism and subclinical Cushing’s syndrome.

Arctigenin (ATG) is a major component of Fructus Arctii, a traditional herbal remedy that reduced proteinuria in diabetic patients. However, whether ATG specifically provides renoprotection in DKD is not known. Here we report that ATG administration is sufficient to attenuate proteinuria and podocyte injury in mouse models of diabetes. Transcriptomic analysis of diabetic mouse glomeruli showed that cell adhesion and inflammation are two key pathways affected by ATG treatment, and mass spectrometry analysis identified protein phosphatase 2 A (PP2A) as one of the top ATG-interacting proteins in renal cells. Enhanced PP2A activity by ATG reduces p65 NF-κB-mediated inflammatory response and high glucose-induced migration in cultured podocytes via interaction with Drebrin-1. Importantly, podocyte-specific Pp2a deletion in mice exacerbates DKD injury and abrogates the ATG-mediated renoprotection. Collectively, our results demonstrate a renoprotective mechanism of ATG via PP2A activation and establish PP2A as a potential target for DKD progression., Arctigenin (ATG) is the major active component of a Chinese herbal remedy known to reduce proteinuria in patients with diabetic kidney disease (DKD). Here, Zhong et al. identify PP2A as a pharmacological target of ATG in podocytes, and find that PP2A is responsible for some of the beneficial effects of ATG in mouse models of DKD.

Plasma aldosterone/renin ratio (ARR) is a useful method for primary aldosteronism (PA) screening. However some confounders, such as medications and dietary, affect plasma renin and aldosterone levels, resulting in false-negative or -positive plasma ARR. This study investigated the association between postmenopausal osteoporosis (PMO) and plasma ARR. Bone mineral density (BMD) was measured by dual-energy X-ray-absorptiometry (DXA) in 324 normotensive postmenopausal women. Based on clinical characteristics and BMD, 186 and 96 subjects were diagnosed as PMO and osteopenia respectively, and the remaining 42 subjects were grouped as normal BMD. Plasma aldosterone concentration (PAC), plasma renin concentration (PRC), parathyroid hormone (PTH), bone alkaline phosphatase (BALP) and 25-Hydroxyvitamin D(25-(OH)D) were determined. Subjects with PMO showed significantly higher levels of PAC (121.0 ± 78.8 vs. 81.8 ± 71.5 pg/ml, p

Acidified sodium chlorite (NaClO2) and sodium hydroxide (NaOH) solutions were successfully used to eliminate lignin and hemicellulose, respectively, from isolated bamboo fibers to investigate their microstructures, composition and micro-tensile properties in individual cellulose fibers. The results demonstrated that isolated fibers and chemically treated fibers clearly displayed different wrinkles, pores and microfibril aggregations on the cell wall surface. Field emission environmental scanning electron microscope images together with confocal scanning laser microscope measurements revealed that chemical treatments have a reduction effect on micro-tensile strength and modulus. Two methods of freeze-drying and air-drying produced varying interfaces and pores in microfibril aggregations and resulted in different tensile behavior. Notably, the reductions of Young’s modulus and tensile strength in freeze-drying (52.99 and 13.32%) fibers are larger than that (18.21 and 10.93%) in air-drying samples. These results suggest that most fractures occur in the weak interspaces or pores that are caused by the loss of matrix materials during chemical treatments.

Rattan-based silicon carbide (R-SiC) ceramics, R-SiCSiO2 and R-SiCSi, were successfully prepared from silica (SiO2) sol and silicon (Si) powder, respectively. The rattan powder was impregnated, respectively, with SiO2 sol at ambient temperature and liquid melt-Si at high temperature. This was followed by one-step direct pyrolysis at 1500 °C under an argon (Ar) atmosphere. The final SiC samples were analyzed using mass analysis, X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), energy dispersive X-ray analysis (EDAX), and nitrogen (N2) physisorption techniques. Experimental results showed that the mass residual of R-SiCSi (42.56 wt%) was almost equal to R-SiCSiO2 (42.45 wt%). However, R-SiCSiO2 had a higher yield of SiC, a higher specific surface area and a more intact porous morphology preserved from the rattan biomass. In addition, some rod-like SiC whiskers and tablet-like SiC particles were found in R-SiCSiO2. By comparison, R-SiCSi had a large amount of unreacted Si, as well as certain amount of SiC and unreacted C. Thus, it can be concluded that SiO2 sols are more appropriate for use in preparation of SiC from rattan, whatever the porous microstructure, yield, and purity of SiC.

The effects of chemical treatments (H2O2 + CH3COOH, acidified NaClO2, and NaOH) and freeze-drying on bamboo fibers were studied at a submicron level, to characterize chemical and mechanical changes to the secondary cell wall. Specifically, a field emission environmental scanning electron microscope (FE-ESEM) and imaging fourier transform infrared spectroscopy (FTIR) were used to demonstrate degradation in morphology and molecular structure, and nanoindentation was used to track changes in micromechanical properties. The results showed that cellular structures after chemical treatments clearly displayed wrinkles, pores, and microfibrils. The decreased bands at 1508 cm-1 and 1426 cm−1 showed that lignin was degraded on treatment of H2O2 + CH3COOH and acidified NaClO2, which directly resulted in a decrease in hardness (H) in the secondary cell wall for treated fibers. In addition, a diminishing peak at 1733 cm−1 caused by NaOH solution indicated that hemicellulose was seriously degraded. It resulted in a decreased modulus (E r) by 13.71 % in bamboo fibers, while no obvious reduction was observed in the first two steps.

Chemical modifications on histones constitute a key mechanism for gene regulation in chromatin context. Recently, histone lysine β-hydroxybutyrylation (Kbhb) was identified as a new form of histone acylation that connects starvation-responsive metabolism to epigenetic regulation. Sirtuins are a family of NAD+-dependent deacetylases. Through systematic profiling studies, we show that human SIRT3 displays class-selective histone de-β-hydroxybutyrylase activities with preference for H3 K4, K9, K18, K23, K27, and H4K16, but not for H4 K5, K8, K12, which distinguishes it from the Zn-dependent HDACs. Structural studies revealed a hydrogen bond-lined hydrophobic pocket favored for the S-form Kbhb recognition and catalysis. β-backbone but not side chain-mediated interactions around Kbhb dominate sequence motif recognition, explaining the broad site-specificity of SIRT3. The observed class-selectivity of SIRT3 is due to an entropically unfavorable barrier associated with the glycine-flanking motif that the histone Kbhb resides in. Collectively, we reveal the molecular basis for class-selective histone de-β-hydroxybutyrylation by SIRT3, shedding lights on the function of sirtuins in Kbhb biology through hierarchical deacylation.

Transcription complexes that assemble at the HIV-1 promoter efficiently initiate transcription but generate paused RNA polymerase II downstream from the start site. The virally encoded Tat protein hijacks positive transcription elongation factor b (P-TEFb) to phosphorylate and activate this paused polymerase. In addition, Tat undergoes a series of reversible post-translational modifications that regulate distinct steps of the transcription cycle. To identify additional functionally important Tat cofactors, we performed RNAi knockdowns of sixteen previously identified Tat interactors and found that a novel E3 ligase, PJA2, ubiquitinates Tat in a non-degradative manner and specifically regulates the step of HIV transcription elongation. Interestingly, several different lysine residues in Tat can function as ubiquitin acceptor sites, and variable combinations of these lysines support both full transcriptional activity and viral replication. Further, the polyubiquitin chain conjugated to Tat by PJA2 can itself be assembled through variable ubiquitin lysine linkages. Importantly, proper ubiquitin chain assembly by PJA2 requires that Tat first binds its P-TEFb cofactor. These results highlight that both the Tat substrate and ubiquitin modification have plastic site usage, and this plasticity is likely another way in which the virus exploits the host molecular machinery to expand its limited genetic repertoire.

A device was designed and assembled to analyze the outgassing of molecular glass (MG) photoresists under extreme ultraviolet (EUV) exposure. The outgassing of the photoresists with different components and different concentrations of tert-butoxycarbonyl (t-Boc), photo-generated acid (PAG), and acid quencher was systematically investigated. Based on experiments, some solutions for reducing the outgassing of MG photoresists were proposed.

Background: The basic studies showed that Pigment epithelium-derived factor (PEDF) plays an important role in inflammation. Aim: This study aims to investigate the association of serum PEDF with high-sensitivity C-reactive protein (hs-CRP) in women with polycystic ovary syndrome (PCOS). Methods: Ninety-six PCOS women and 63 healthy, age-matched controls were enrolled in this study. Serum levels of PEDF, hs-CRP, Complement C3 (C3), glucose, insulin, lipids, and total testosterone were measured. Ninety-six PCOS women and 20 controls underwent hyperinsulinemic-euglycemic clamp to assess their insulin sensitivity, which was expressed as M value. Results: Serum PEDF levels and hs-CRP levels were much higher in PCOS women than in controls. In PCOS women, PEDF positively correlated with body mass index (BMI), hs-CRP, C3, LDL cholesterol (LDL-c), and systolic blood pressure (SBP), and negatively correlated with M value and HDL cholesterol (HDL-c). After controlling for BMI, PEDF was still positively correlated with hs-CRP. Multiple linear regression analysis revealed that in PCOS women, hs-CRP, SBP, LDL-c and M value were independent determinants of serum PEDF. Conclusion: The serum PEDF levels are closely associated with hs-CRP in women with PCOS. PEDF may play a role in the development of chronic inflammation in PCOS.

A new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO2-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO4 aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO2. The growing and the as-formed SnO2, just like other photocatalytic semiconductor, could be excited to produce electrons and holes under UV irradiation. Electrons reduced GO and holes adsorbed corresponding negative ions, which changed the properties of the composite film. This film was directly used as gas-sensor and was able to display high sensitivity in detecting ethanol gas. More interestingly, on the basis of SnO2-induced photochemical behaviours, this sensor demonstrated tunable sensitivity when UV irradiation time was controlled during the fabrication process and post in water, respectively. This study provides efficient ways of conducting the in situ fabrication of a semiconductor-reduced graphite oxide film device with uniform surface structure and controllable properties.