Synergistic therapeutic effect of ginsenoside Rg3 modified minoxidil transfersomes (MXD-Rg3@TFs) on androgenic alopecia in C57BL/6 mice.

Inflammation in hair follicles will reduce the effectiveness of minoxidil (MXD) in the treatment of androgen alopecia (AGA) caused by elevated androgen levels. To target multiple physiological and pathological processes in AGA, a novel natural bioactive compound modified transfersomes (MXD-Rg3@TFs) was prepared to replace cholesterol that may disrupt hair growth, with ginsenosides Rg3 (Rg3) that have anti-inflammatory effects on AGA. The effects of MXD, Rg3 and their combination on AGA were evaluated using dihydrotestosterone (DHT) induced human dermal papilla cells (DPCs), and the results showed that the combination of MXD and Rg3 can significantly promote the proliferation, reduce the level of intracellular ROS and inflammatory factors, and inhibit the aging of DHT induced DPCs. Compared with cholesterol membrane transfersomes (MXD-Ch@TFs), MXD-Rg3@TFs has similar deformability, smaller particle size and better stability. MXD-Rg3@TFs has also significant advantages in shortening telogen phase and prolonging the growth period of hair follicles in C57BL/6 mice than MXD-Ch@TFs and commercial MXD tincture. The prominent ability of MXD-Rg3@TFs to inhibit the conversion of testosterone to DHT and reduce the level of inflammatory factors suggested that Rg3 and MXD in MXD-Rg3@TFs have synergistic effect on AGA therapy. MXD-Ch@TFs with no irritation to C57BL/6 mice skin is expected to reduce the dose of MXD and shorten the treatment time, which would undoubtedly provide a promising therapeutic option for treatment of AGA.

PROTACs Targeting BRM (SMARCA2) Afford Selective In Vivo Degradation over BRG1 (SMARCA4) and Are Active in BRG1 Mutant Xenograft Tumor Models.

The identification of VHL-binding proteolysis targeting chimeras (PROTACs) that potently degrade the BRM protein (also known as SMARCA2) in SW1573 cell-based experiments is described. These molecules exhibit between 10- and 100-fold degradation selectivity for BRM over the closely related paralog protein BRG1 (SMARCA4). They also selectively impair the proliferation of the H1944 "BRG1-mutant" NSCLC cell line, which lacks functional BRG1 protein and is thus highly dependent on BRM for growth, relative to the wild-type Calu6 line. In vivo experiments performed with a subset of compounds identified PROTACs that potently and selectively degraded BRM in the Calu6 and/or the HCC2302 BRG1 mutant NSCLC xenograft models and also afforded antitumor efficacy in the latter system. Subsequent PK/PD analysis established a need to achieve strong BRM degradation (>95%) in order to trigger meaningful antitumor activity in vivo. Intratumor quantitation of mRNA associated with two genes whose transcription was controlled by BRM (PLAU and KRT80) also supported this conclusion.

A study on the preparation conditions of lidocaine microemulsion based on multi-objective genetic algorithm.

Background: Topical lidocaine microemulsion preparations with low toxicity, low irritation, strong transdermal capability and convenient administration are urgently needed. Methods: Box-Behnken design was performed for three preparation conditions of 5% lidocaine microemulsions: mass ratio of the mass ratio of surfactant/(oil phase + surfactant) (X1), the mass ratio of olive oil/(α-linolenic acid + linoleic acid) (X2) and the water content W% (X3). Then, five multi-objective genetic algorithms were used to optimize the three evaluation indices to optimize the effects of lidocaine microemulsion preparations. Finally, the ideal optimization scheme was experimentally verified. Results: Non-dominated Sorting Genetic Algorithm-II was used for 30 random searches. Among these, Scheme 2: X1 = 0.75, X2 = 0.35, X3 = 75%, which resulted in Y1 = 0.17 µg/(cm2·s) and Y2 = 0.74 mg/cm2; and the Scheme 19: X1 = 0.68, X2 = 1.42, X3 = 75% which resulted in Y1 = 0.14 µg/(cm2·s) and Y2 = 0.80 mg/cm2, provided the best matches for the objective function requirements. The maximum and average fitness of the method have reached stability after 3 generations of evolution. Experimental verification of the above two schemes showed that there were no statistically significant differences between the measured values of Y1 and Y2 and the predicted values obtained by optimization (p > 0.05) and are close to the target value. Conclusion: Two lidocaine microemulsion preparation protocols were proposed in this study. These preparations resulted in good transdermal performance or long anesthesia duration, respectively.

Second-Generation Atroposelective Synthesis of KRAS G12C Covalent Inhibitor GDC-6036.

A chromatography-free asymmetric synthesis of GDC-6036 (1) was achieved via a highly atroposelective Negishi coupling of aminopyridine 5 and quinazoline 6b catalyzed by 0.5 mol % [Pd(cin)Cl]2 and 1 mol % (R,R)-Chiraphite to afford the key intermediate (Ra)-3. An alkoxylation of (Ra)-3 with (S)-N-methylprolinol (4) and a global deprotection generates the penultimate heterobiaryl intermediate 2. A controlled acrylamide installation by stepwise acylation/sulfone elimination and final adipate salt formation and crystallization delivered high-purity GDC-6036 (1).

A theoretical investigation on the synergetic effect of hydrogen-bonding interactions and thermodynamic property in the 1: 2 (azacyclopentane-2-one: N-methylolacetamide) ternary complex.

CONTEXT: Using chemical penetration enhancers to improve the penetration effect is one kind of important strategies in transdermal drug delivery system. Azone is a widely used transdermal absorption enhancer for transdermal drug delivery. To shed light on the permeation-promoting mechanism of azone, we selected ternary systems formed by azacyclopentane-2-one and N-methylolacetamide (1: 2) and explored the synergetic effect of hydrogen-bonding interactions among them and their thermodynamic properties. The findings indicate that the synergetic effects can enhance the ability of azone to change the original conformation of ceramides and even break the original hydrogen bonds, which is more beneficial for azone to destroy the 3D network structure of ceramides. When azone interacts with ceramide, the order of action tends to interact with one molecule of ceramide first and then with another molecule of ceramide. METHODS: The synergetic effects of hydrogen-bonding interactions in ternary systems were computed at the B3LYP/6-311 + + G** and MP2(full)/6-311 + + G** levels. Thermodynamic parameters for two ternary-complex routes were worked out at the B3LYP/aug-cc-pVDZ level. The shift of the electron density occurring simultaneously with trimer formation was analyzed at the MP2(full)/6-311 + + G** level. The above calculations were carried out using the Gaussian 03 program packages. Atoms in molecules (AIM) method and the AIMPAC program showed the topological charge density at the MP2(full)/6-311 + + G** level. The synergetic effects of hydrogen-bonding interactions and thermodynamic property in the 1: 2 (azacyclopentane-2-one: N-methylolacetamide) ternary systems were investigated using the B3LYP and MP2(full) methods.

Identification of key pharmacodynamic markers of American ginseng against heart failure based on metabolomics and zebrafish model.

Background: American ginseng (Panax quinquefolium L., AG) is a traditional Chinese medicine with multiple cardiovascular protective properties. Many bioactive components have been discovered in AG over these years. However, the understanding of these key pharmacodynamic components of activity against heart failure is insufficient. Methods: A heart failure model was established using AB line wild-type zebrafish (Danio rerio) to evaluate the anti-heart failure activity of AG. Untargeted metabolomics analysis based on ultra-high performance liquid chromatography-quadrupole electrostatic field orbitrap-mass spectrometry technology (UHPLC-QE-Orbitrap-MS) was performed to screen differential components from AG samples. The potential active components were verified using the zebrafish model. Simultaneously, network pharmacology and molecular docking techniques were used to predict the possible mechanism. Finally, the key targets of six key pharmacodynamic components were verified in zebrafish using quantitative real-time-polymerase chain reaction (Q-PCR) techniques. Results: The heart failure model was successfully established in 48 h of post-fertilization (hpf) zebrafish larvae by treating with verapamil hydrochloride. The zebrafish assay showed that the anti-heart failure effects of AG varied with producing regions. The result of the herbal metabolomic analysis based on UHPLC-QE-Orbitrap-MS indicated that ginsenoside Rg3, ginsenoside Rg5, ginsenoside Rg6, malic acid, quinic acid, L-argininosuccinic acid, 3-methyl-3-butenyl-apinosyl (1→6) glucoside, pseudoginsenoside F11, and annonaine were differential components, which might be responsible for variation in efficacy. Further analysis using zebrafish models, network pharmacology, and Q-PCR techniques showed that ginsenoside Rg3, ginsenoside Rg5, ginsenoside Rg6, malic acid, quinic acid, and pseudoginsenoside F11 were the pharmacodynamic markers (P-markers) responsible for anti-heart failure. Conclusion: We have rapidly identified the P-markers against heart failure in AG using the zebrafish model and metabolomics technology. These P-markers may provide new reference standards for quality control and new drug development of AG.

An Integrated Strategy for Rapid Discovery and Identification of Quality Markers in Gardenia Fructus Using an Omics Discrimination-Grey Correlation-Biological Verification Method.

Background: Gardenia Fructus (GF), a traditional Chinese medicine of Gardenia Ellis in Rubiaceae family, has the potential to clear heat and purge fire and has been widely used to treat multiple infection-related diseases. However, the quality markers (Q-Markers) of GF have not been revealed comprehensively. Methods: In this experiment, the transgenic zebrafish lines, Tg (l-fabp:EGFP) and Tg (lyz:EGFP), were used to evaluate two main kinds of traditional efficacies of GF, hepatoprotective and anti-inflammatory effects. All the GF samples from different production areas were tested their anti-liver injury and anti-inflammantory activities. High-performance liquid chromatography-quadrupole time-of-flight mass spectrometry method (HPLC-Q-TOF/MS) was employed for herbal metabonomic analysis of GF samples. Gray correlation analysis (GCA) was utilized to screen out the components closely associated with the activities. Finally, the zebrafish model was applied to verify the bioactivity of the crucial components to determine the Q-Markers of GF. Results: The zebrafish models were established by inducing with hydrogen peroxide or copper sulfate and applied to quickly evaluate the hepatoprotective effect and inflammation of GF samples. 27 potentially active components for liver protection and 21 potentially active components with anti-inflammatory properties were identified by herbal metabolomic analysis based on HPLC-Q-TOF/MS. The GCA result showed that five of the 27 components were highly correlated with liver protection, 15 of the 21 components were highly correlated with anti-inflammatory activity. Among them, geniposide and crocin-1 were confirmed their bioactivities on zebrafish experiment to be responsible for the protective effects of GF against liver injury, and genipin-1-ß-D-gentiobioside, quinic acid, gardenoside, d-glucuronic acid, l-malic acid, mannitol, rutin, and chlorogenic acid were confirmed to be responsible for the anti-inflammatory effects. Finally, according to the screening principles of Q-Markers, genipin-1-ß-D-gentiobioside, geniposide, and gardenoside were preliminarily identified to be the Q-Markers of GF. Conclusion: This study established an effective research strategy of "Omics Discrimination-Grey Correlation-Biological Verification," which enabled the rapid identification of key pharmacological components of GF. These markers have provided a scientific basis for constructing a modern quality evaluation system for GF.

Plasma Level of Elabela in Patients with Coronary Heart Disease and Its Correlation with the Disease Classification.

This study aimed to evaluate the concentration of plasma elabela (ELA) in patients with coronary heart disease (CHD) and its correlation with the disease classification.We enrolled 238 patients diagnosed by coronary angiography as CHD and 86 controls. The CHD group was divided into three subgroups: stable angina (SA), unstable angina (UAP), and acute myocardial infarction (AMI). The plasma levels of ELA were measured in all participants and compared among different groups. The relationship between ELA and CHD classification was analyzed.ELA levels were markedly higher by 10.71% in patients with CHD than in controls (P < 0.05). The concentration of ELA in UAP and AMI subgroups were higher than in controls and SA subgroup. The former difference was significant (P < 0.05), but the latter was not. In addition, the ELA concentration was not correlated with SYNTAX score, left ventricular ejection fraction, and other biochemical variables.The newfound hormone, ELA, significantly increased in patients with UAP and AMI. There is a tendency that ELA levels might be correlated with CHD classification, but not with lesion severity. ELA may play a role in acute coronary syndrome.

Formulation and evaluation of a α-linolenic acid and vitamin E succinate microemulsion with low surfactant content and free of co-surfactant for use as a nutritional supplement.

Herein, we have designed an alcohol-free and low-surfactant microemulsion to safely and effectively supply α-linolenic acid (ALA) and vitamin E (VE). Ternary phase diagrams show that the use of medium- or short-chain alcohols as the co-surfactant (CoS) was unfavorable for the formation of the ALA microemulsion due to the competitive hydrogen bonding effect and vitamin E succinate (VES) significantly increased the ALA microemulsion region by improving the hydrophilicity of the oil phase. The optimal microemulsion formulation (Mav) was 6.86% ALA, 1.14% VES, 12% surfactant and 80% water, with uniformly dispersed spherical particles with diameters of ~ 25.41 nm and viscosity of 35.17 mPa·s. The Mav was stable to high temperature, ionic strength and pH, and exhibited good physical and anti-oxidation stability. The Mav facilitated the release and hydrolysis of VES, indicating that the CoS-free microemulsion with low surfactant content is promising for the safe and effective supply of ALA and VE.

Clozapine Induced Developmental and Cardiac Toxicity on Zebrafish Embryos by Elevating Oxidative Stress.

Clozapine is one of the antipsychotic drugs for treating schizophrenia, but its cardiotoxicity was the primary obstacle for its clinical use, due to the unknown mechanism of clozapine-induced cardiotoxicity. In this study, we studied the cardiotoxicity of clozapine by employing zebrafish embryos. Acute clozapine exposure showed dose-dependent mortality with the LC50 at 59.36 µmol L-1 and 49.60 µmol L-1 when determined at 48 and 72 h post exposure, respectively. Morphological abnormalities like pericardial edema, incompletely heart looping, and bradycardia were detected after clozapine exposure in a time- and dose-dependent manner. Clozapine treatment also resulted in a slower heart rate and disturbed rhythm in zebrafish embryos. Also, oxidative stress was observed after clozapine exposure by measurement of ROS (reactive oxygen species), MDA (a lipid peroxidation marker), antioxidant enzyme activities, and oxidative stress-related gene expression. The elevation of inflammation coincided with oxidative stress by the assay of inflammation-related genes expression accompanied by clozapine incubation. Collectively, the data indicate that clozapine might achieve cardiotoxic effect in zebrafish larva through increasing oxidative stress, attenuation in antioxidant defense, and up-regulation of inflammatory cytokines. The data could provide experimental explanations for myocarditis and pericarditis induced by clozapine in clinics, and help find an effective solution to reduce its cardiotoxicity.

Design, optimization and evaluation of co-surfactant free microemulsion-based hydrogel with low surfactant for enhanced transdermal delivery of lidocaine.

Microemulsion is the preferred vehicle for local anesthetics; however, the toxicity and irritation associated with a quantity use of surfactants (S) and co-surfactants (CS), i.e., medium- or short-chain alcohols, restrict its commercial application. In this study, efforts have been made to enlarge the CS-free microemulsion area by mixing olive oil (OL) with α-linolenic acid (ALA) and linoleic acid (LA), and by using vitamin E succinate (VES) as an auxiliary oil. Through Box-Behnken design and the optimization of nondominated sorting genetic algorithm II, the optimal microemulsion formulation (ME0) with a large steady-state simultaneous permeation rate (Js) and skin retention was screened as 3.23% OL, 0.45% ALA, 1.81% LA, 0.91% VES, 13.60% S, 5% lidocaine and water. Three percent ethanol was screened as a permeability enhancer for the hydrogel of ME0, which showed a statistical increase in Js and skin retention through the abdominal skin of guinea pigs. The optimized formulation had desirable characterization, good stability and negligible irritation. The large Js and skin retention were well reflected in the pinprick test, wherein intensity of anesthetic effect and duration of action were increased significantly over the commercial cream. The developed CS-free microemulsion hydrogel with low S could be a promising strategy for the topical delivery of lidocaine.

Discovery and identification of antithrombotic chemical markers in Gardenia Fructus by herbal metabolomics and zebrafish model.

ETHNOPHARMACOLOGICAL RELEVANCE: Gardenia Fructus (GF), a traditional Chinese medicine for clearing heat and purging fire, has been reported to use to treat thrombotic related diseases, but the antithrombotic components are not clear. AIM OF THE STUDY: To develop efficient research methods for discovering some representative antithrombotic compounds of GF. MATERIALS AND METHODS: AB line zebrafish induced by arachidonic acid (AA) was used as a fast and trace-sample-required valuation model for antithrombptic effect of GF samples. Among nine samples of GF from different production areas, two samples with the largest difference in bioactivity were selected for downstream analysis. High-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF/MS) was applied to detect compounds in the GF samples. And herbal metabolomics and grey correlation analysis (GCA) were used to identify crucial compounds with potential antithrombotic activity. Then the bioactivity of those important compounds was verified on the zebrafish model. Network pharmacology was used to explore the protein targets and signaling pathways of these compounds. RESULTS: Among the GF samples, S1 (Huoshan City, Anhui Province), and S6 (Jichun City, Hubei Province), significantly differed in thrombus inhibiting bioactivity. HPLC-Q-TOF/MS identified a total of 614 compounds in each GF sample. 19 compounds were selected as important potential variables from metabolomics data by orthogonal partial least squares discriminant analysis (OPLS-DA). And 10 compounds among them were further found to be positively correlated with the antithrombotic bioactivity of GF by GCA. Finally, 3 compounds in them, geniposide, citric acid, and quinic acid, were confirmed as representative antithrombotic chemical markers of GF. Using network pharmacology analysis, some key protein targets, such as proto-oncogene tyrosine-protein kinase Src (SRC) and cyclin-dependent kinase 2 (CDK2), and some signaling pathways were found to supply powerful evidence about antithrombotic mechanisms of three compounds and GF. CONCLUSIONS: This research have succeeded to discover and identify three representative antithrombotic compounds of GF using an efficient integrated research strategy we established, an Omics Discriminant-Grey Correlation-Biological Activity strategy. The antithrombotic chemical makers we found could also contribute to provided more accurate index components for comprehensive quality control of GF.

Delivery of Antisense Oligonucleotide LOR-2501 Using Transferrin-conjugated Polyethylenimine-based Lipid Nanoparticle.

BACKGROUND/AIM: Efficient delivery of antisense oligonucleotide (ASO) by nanoparticle vectors is critical for its clinical application. The aim of this study was to design and evaluate a novel ASO vector TPSH-LP consisting of a reduction-sensitive cationic polymer PEI-SS-HA (PSH), lipids and transferrin (Tf) as a targeting ligand. MATERIALS AND METHODS: PSH was synthesized based on PEI 25 kDa. Nanoparticles containing PSH and Tf (TPSH-LP) were prepared and used to deliver an ASO LOR-2501 targeting ribonucleotide reductase R1. The physical and chemical properties of TPSH-LP and cellular uptake in HepG2 cells were studied. RESULTS: TPSH-LP formed a complex with LOR-2501 (L-TPSH-LP) which showed suitable particle size (267.77±16.20 nm) and zeta potential (4.87±0.52 mV). TPSH-LP showed lower cytotoxicity and higher transfection efficiency than PEI 25 kDa in HepG2 cells. The addition of Tf enhanced the targeting and delivery efficiency of PSH-LP. TPSH-LP transported LOR-2501 and down-regulated the levels of R1 protein efficiently by 64.15%. CONCLUSION: Data demonstrated the potential utility of TPSH-LP for oligonucleotide delivery in cancer therapy.

Association of Circulating Neuregulin-4 with Presence and Severity of Coronary Artery Disease.

Neuregulin-4 (Nrg4) is a newly discovered adipokine that is synthesized in many tissues and plays an important role in modulating systemic energy metabolism and in the development of metabolic disorders. However, little is known about the relationship between Nrg4 and coronary artery disease (CAD). In this study, we investigated the association between Nrg4 and the presence and severity of CAD.We enrolled 73 patients diagnosed by coronary angiography (CAG) as having CAD and 32 controls. The CAD group was divided into two subgroups according to their SYNTAX score. Plasma levels of Nrg4 were measured in all participants and compared among different groups. The relationship between Nrg4 and CAD was analyzed. Receiver operating characteristic (ROC) analysis was conducted to evaluate the usefulness Nrg4 in assessing the presence and severity of CAD.Nrg4 levels were negatively associated with the SYNTAX score (r = -0.401, P = 0.000). The patients with a higher SYNTAX score had significantly lower Nrg4 levels as compared with the low SYNTAX score subgroup and the controls (P < 0.05). The Nrg4 levels of the low SYNTAX score subgroup were much lower than controls (P < 0.05). Furthermore, an association between Nrg4 and CAD (odds ratio, 0.279; 95% confidence interval, 0.088-0.882) was observed. Nrg4 had 43.8% sensitivity and 96.9% specificity for identifying CAD, and 73.1% sensitivity and 87.3% specificity for identifying patients who had severe coronary artery lesions.Nrg4 levels were found to be inversely associated with the presence and severity of CAD.

Xiaoaiping Induces Developmental Toxicity in Zebrafish Embryos Through Activation of ER Stress, Apoptosis and the Wnt Pathway.

The aim of the study was to determine the developmental toxicity of the traditional Chinese medicine Xiaoaiping (XAP) and to investigate its underlying mechanism of action. Zebrafish embryos were incubated with 0.4, 0.8, 1.2, and 1.6 mg/mL XAP. Endpoints such as mortality, hatching rate, malformation, body length, morphology score, swimming behavior, histological changes, reactive oxygen species (ROS) production, total superoxide dismutase (T-SOD) activity, and the mRNA expression of genes related to oxidative stress, endoplasmic reticulum (ER) stress, apoptosis, and the Wnt pathway were evaluated. Our results demonstrated that XAP exposure increased mortality and malformation and reduced the hatching rate. XAP resulted in severe malformation, including swim bladder deficiency, yolk retention, pericardial edema, and tail curvature. Histopathological analysis showed that XAP induced liver, heart and muscle injury. High doses (≥1.2 mg/mL) of XAP notably decreased the locomotor capacity of zebrafish. ROS generation was remarkably increased and T-SOD activity was decreased, confirming that oxidative stress was induced by XAP. The mRNA expression levels of ER stress-related genes (chop, hspa5, hsp90b1, and perk), apoptosis-related genes (caspase-3, bax, and p53) and wnt11 were significantly upregulated by XAP exposure. The expression levels of the oxidative stress-related genes (cat, sod1, and gstp2), Wnt pathway-related genes (ß-catenin, wnt3a, and wnt8a) and bcl-2 initially increased and then decreased as the XAP exposure dose increased. In conclusion, we provide evidence for the first time that XAP can induce dose-related developmental toxicity, and ER stress, apoptosis and the Wnt pathway participate in the toxicity regulation.

Tenacissoside H exerts an anti-inflammatory effect by regulating the nf-κb and p38 pathways in zebrafish.

Marsdenia tenacissima exhibits biological activity with heat-clearing and detoxifying properties, relieving coughs and asthma and exerting anticancer and anti-HIV effects. Tenacissioside H (TH) is a Chinese medicine monomer extracted from the dried stem of Marsdenia tenacissima. We investigated the in vivo anti-inflammatory activity of TH using three different zebrafish inflammation models: local inflammation induced by tail cutting, acute inflammation induced by CuSO4, and systemic inflammation induced by lipopolysaccharide (LPS). Real time-polymerase chain reaction (RT-PCR) was used to elucidate the mechanism of TH action against LPS-induced inflammatory responses. Our results showed TH significantly reduced the number of macrophages in the injured zebrafish tail, inhibited CuSO4-induced migration of macrophages toward the neural mound, and decreased the distribution of macrophages in tail fin compared to LPS-treated group. Furthermore, TH inhibits LPS-induced inflammation responses in zebrafish by modulating the nuclear factor κB (nf-κb) and p38 pathways to regulate inflammatory cytokines, such as tumor necrosis factor-α (tnf-α), cyclooxygenase (cox-2), interleukin-1b (il-1b), interleukin-8 (il-8), interleukin-10 (il-10), nitric oxide synthase (nos2b) and prostaglandin E synthase (ptges). In conclusion, TH possesses anti-inflammation activity via the regulation of the nf-κb and p38 pathways. This finding provides a reference for the clinical application of Xiaoaiping (the trade name of Marsdenia tenacissima extract).

Theoretical investigations into the intermolecular hydrogen-bonding interactions of N-(hydroxymethyl)acetamide dimers.

The structures of the N-(hydroxymethyl)acetamide (model molecule of ceramide) dimers have been fully optimized at B3LYP/6-311++G** level. The intermolecular hydrogen bonding interaction energies have been calculated using the B3LYP/6-311++G**, B3LYP/6-311++G(2df,2p), MP2(full)/6-311++G** and MP2(full)/6-311++G(2df,2p) methods, respectively. The results show that the O-H···O, N-H···O, O-H···N, and C-H···O hydrogen bonding interactions could exist in N-(hydroxymethyl)acetamide dimers, and the O-H···O, N-H···O, and O-H···N hydrogen bonding interactions could be stronger than C-H···O. The three-dimensional network structure formed by ceramide molecules through intermolecular hydrogen bonding interactions may be the main reason why the stratum corneum of skin could prevent foreign substances from entering our body, as is in accordance with the experimental results. The stability of hydrogen-bonding interactions follow the order of (a) > (b) ≈ (c) > (d) > (e) ≈ (f) > (g) > (h). The analyses of the energy decomposition, frequency, atoms in molecules (AIM), natural bond orbital (NBO), and electron density shift are used to further reveal the nature of the complex formation. In the range of 263.0-328.0 K, the complex is formed via an exothermic reaction, and the solvent with lower temperature and dielectric constant is favorable to this process. Graphical abstract The structures and the O-H···O=C, N-H···O=C and C-H···O=C H-bonding interactions in the N-(hydroxymethyl)acetamide (model molecule of ceramide) dimers were investigated using the B3LYP and MP2(full) methods.

Fast and automatic imaging of immunoenzyme-stained neuronal circuits in the whole brain of Drosophila.

Knowledge of neuronal wiring and morphogenesis in Drosophila is essential to understand brain function and dysfunction. The immunoenzyme method based on horseradish peroxidase/diaminobenzidine (HRP/DAB) provides high-contrast images to resolve details underlying neuronal architecture. However, the poor staining penetration and a lack of corresponding three-dimensional imaging methodology limit its application. Herein, we modified the HRP/DAB method to stain neuronal circuits in the whole brain of Drosophila. Furthermore, we found that imaging with the micro-optical sectioning tomography system provided a fast and automatic method that could dissect cell-specific neuroanatomical architecture at a submicron voxel resolution.

A theoretical investigation into the cooperativity effect between the H∙∙∙O and H∙∙∙F⁻ interactions and electrostatic potential upon 1:2 (F⁻:N-(Hydroxymethyl)acetamide) ternary-system formation.

The cooperativity effects between the O/N-H∙∙∙F(-) anionic hydrogen-bonding and O/N-H∙∙∙O hydrogen-bonding interactions and electrostatic potentials in the 1:2 (F(-):N-(Hydroxymethyl)acetamide (signed as "ha")) ternary systems are investigated at the B3LYP/6-311++G** and MP2/6-311++G** levels. A comparison of the cooperativity effect in the "F(-)∙∙∙ha∙∙∙ha" and "FH∙∙∙ha(-)∙∙∙ha" systems is also carried out. The result shows that the increase of the H∙∙∙O interaction energy in the O-H∙∙∙O-H, N-H∙∙∙O-H or N-H∙∙∙O = C link is more notable than that in the O-H∙∙∙O = C contact upon ternary-system formation. The cooperativity effect is found in the complex formed by the O/N-H∙∙∙F(-) and O/N-H∙∙∙O interactions, while the anti-cooperativity effect is present in the system with only the O/N-H∙∙∙F(-) H-bond or the "FH∙∙∙ha(-)∙∙∙ha" complex by the N(-)∙∙∙H-F contact. Atoms in molecules (AIM) analysis and shift of electron density confirm the existence of cooperativity. The most negative surface electrostatic potential (V(S,min)) correlates well with the interaction energy E' int.(ha∙∙∙F-) and synergetic energy E(syn.), respectively. The relationship between the change of V(S,min) (i.e., ΔV(S,min)) and E(syn.) is also found.

Preparation of high solubilizable microemulsion of naproxen and its solubilization mechanism.

To improve the skin permeation of naproxen with larger dosage, microemulsion with high content of naproxen was investigated for transdermal delivery and its solubilization mechanism was studied. Naproxen micoremulsions composed of 4% isopropyl myristate, 18% Tween 80, 18% ethanol and water were prepared and phase inversion temperature (PIT) method was used to increase drug content. The using of PIT method resulted in the maximum content of naproxen in microemulsion increased from 1.98 ± 0.13% to 4.12 ± 0.07%, accordingly the permeation rate of naproxen from microemulsion through excised mice skin increased from 135.13 ± 5.50 to 214.46 ± 7.53 µg cm(-2)h(-1). The analyses of Natural Bond Orbital and interaction energy using the B3LYP and MP2 (fc) methods suggested that the solubilization mechanism of microemulsion for naproxen mainly might be the formation of complex between the hydrogen atom of hydroxyl in Tween 80 and the oxygen atom of carbonyl group in naproxen, as is in accordance with the result from (1)H NMR experiments. The change of thermodynamic function with temperature confirmed that, because the complex was easy to be formed in high temperature and that formed at PIT became more stable when the temperature decreased to below PIT, the solubilization ability of microemulsion for naproxen could be improved by the PIT method. The powerful permeation enhancing ability of microemulsion induced by the solubilization of PIT method makes it a promising vehicle for the transdermal delivery of naproxen.