Confined Formation of Ultrathin ZnO Nanorods/Reduced Graphene Oxide Mesoporous Nanocomposites for High-Performance Room-Temperature NO2 Sensors

Here we demonstrate high-performance room-temperature NO₂ sensors based on ultrathin ZnO nanorods/reduced graphene oxide (rGO) mesoporous nanocomposites. Ultrathin ZnO nanorods were loaded on rGO nanosheets by a facile two-step additive-free solution synthesis involving anchored seeding followed by oriented growth. The ZnO nanorod diameters were simply controlled by the seed diameters associated with the spatial confinement effects of graphene oxide (GO) nanosheets. Compared to the solely ZnO nanorods and rGO-based sensors, the optimal sensor based on ultrathin ZnO nanorods/rGO nanocomposites exhibited higher sensitivity and quicker p-type response to parts per million level of NO₂ at room temperature, and the sensitivity to 1 ppm of NO₂ was 119% with the response and recovery time being 75 and 132 s. Moreover, the sensor exhibited full reversibility, excellent selectivity, and a low detection limit (50 ppb) to NO₂ at room temperature. In addition to the high transport capability of rGO as well as excellent NO₂ adsorption ability derived from ultrathin ZnO nanorods and mesoporous structures, the superior sensing performance of the nanocomposites was attributed to the synergetic effect of ZnO and rGO, which was realized by the electron transfer across the ZnO-rGO interfaces through band energy alignment.

Benzoate fraction from Gentiana rigescens Franch alleviates scopolamine-induced impaired memory in mice model in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

G. rigescens Franch (Long Dan Cao in Chinese) is a well-known TCM herb. It is clinically used with other drugs for the treatment of brain diseases such as epilepsy, postherpetic neuralgia in China.

AIM OF STUDY

In our previous study, the 11 dihydroxybenzoates compounds with NGF mimicking activity from G. rigescens Franch were found. In the present study, the neurogenesis and neuroprotection of a mixture of benzoates ( n-GS) were investigated in animal level.

MATERIALS AND METHODS

The NGF mimicking activity of n-GS from G. rigescens Franch was examined in PC12 cells. The neurogenesis effects of n-GS were investigated in ICR mice with 5-bromo-2-deoxyuridine (BrdU) and neuronal neclei (NeuN) double immunostaining. Furthermore, the neuroprotection effects of n-GS on the memory in a scopolamine (SCO)-induced mouse model were evaluated with animal behavior tests.

RESULTS

The NGF-mimicking function and neurogenesis of n-GS were observed in PC12 cells and in normal mice. Subsequently, we investigated the effects of n-GS on the memory in a SCO-induced mouse model. In Y-maze test, SCO significantly lowered the alternation. This finding was reversed by n-GS and donepezil (DONE). SCO significantly impaired the mice's performance in novel object recognition (NOR) and Morris water maze (MWM) tests. The time spent to explore the novel object was longer in the n-GS- and DONE-treated groups than in the SCO control group. In the MWM test, the escape latency of n-GS- and DONE-treated groups was shorter than that of the SCO control group. Mechanism study showed that SCO significantly reduced superoxide dismutase (SOD) but increased the activities of acetylcholinesterase (AChE) and the levels of malondialdehyde (MDA) in the hippocampus and cerebral cortex, which all can be improved by n-GS and DONE. Additionally, the phosphorylation of type 1 insulin-like growth factor (IGF-1) receptor, extracellular signal-regulated kinase (ERK), and cAMP responsive element-binding (CREB) protein in the hippocampus was significantly up-regulated in the treatment group compared with that in the SCO group.

CONCLUSIONS

n-GS could alleviate impaired memory of the SCO-induced mice model by inhibiting AChE activity and oxidative stress, and regulating the IGF-1R/ERK signaling pathway.

Synthesis and SAR Studies of Neuritogenic Gentiside Derivatives

Tetradecyl 2,3-dihydroxybenzoate (ABG-001) has been designed and synthesised as a lead compound to treat Alzheimer's disease, based on structure-activity relationships of gentisides. In this paper, the alkyl chain and ester linkage group of ABG-001 were modified. Consequently, several series of novel gentiside derivatives were designed and synthesised, and their neuritogenic activity was evaluated in PC12 cells. Among all the tested compounds, S-dodecyl 2,3-dihydroxybenzothioate (15d, named as ABG-199) was the most potent; the compound induced significant neurite outgrowth at 0.1 µM, which was comparable to that of nerve growth factor at the optimal concentration of 40 ng/mL and ABG-001 at 1 µM. A brief study on the mechanism of action of ABG-199 revealed that extracellular signal-regulated kinase phosphorylation was involved in ABG-199-induced neurite outgrowth in PC12 cells.

Prospective cohort study of laparoscopic and open hepatectomy for hepatocellular carcinoma

BACKGROUND

The safety and feasibility of laparoscopic hepatectomy for hepatocellular carcinoma (HCC) with a diameter of 5 cm or less is well recognized. The role of laparoscopy in treating large HCC (5-10 cm) remains controversial. This prospective cohort study was undertaken to assess the short- and long-term outcomes of laparoscopic hepatectomy for large HCC and to compare this approach with open hepatectomy.

METHODS

Patients with a solitary HCC (diameter 5-10 cm) who underwent open or laparoscopic hepatectomy were enrolled in a prospective observational study from January 2012 to April 2015. Perioperative and follow-up data were analysed.

RESULTS

Some 128 patients underwent laparoscopic hepatectomy and 207 had an open hepatectomy. One and two perioperative deaths were reported in the laparoscopic and open groups respectively. Laparoscopic hepatectomy was converted to an open procedure in 12 (9·4 per cent) of 128 patients. More patients in the laparoscopic group underwent an anatomical hepatectomy than in the open group (45·3 versus 21·7 per cent; P = 0·001). The postoperative complication rate was 20·3 per cent for the laparoscopic group versus 35·7 per cent for the open group (P = 0·003). Mean(s.d.) duration of hospital stay was 11·4(3·1) and 15·8(7·7) days respectively (P < 0·001). One- and 3-year overall survival rates in the laparoscopic and open groups were 94·4 versus 93·6 per cent (P = 0·875), and 81·4 versus 82·2 per cent (P = 0·802), respectively. One- and 3-year disease-free survival rates were 89·4 versus 88·7 per cent (P = 0·825), and 67·3 versus 66·7 per cent (P = 0·902), respectively.

CONCLUSION

Laparoscopic hepatectomy is safe and feasible for the treatment of patients with large HCC.

Racemic oleracein E increases the survival rate and attenuates memory impairment in D-galactose/NaNO₂-induced senescent mice

BACKGROUND

Compounds that possess a pyrrolidone skeleton are a rich resource for the discovery of nootropic drugs. Oleracein E (OE), which possesses both tetrahydroisoquinoline and pyrrolidone skeletons, was first isolated from the medicinal plant Portulaca oleracea L. and was thought to be an active component in the cognition-improvement effect induced by this herb. The aim of this study was to investigate the effect of OE on cognitive impairment in senescent mice and its underlying mechanism of action.

METHOD

Senescent Kunming mice were established by the intraperitoneal injection of D-galactose (D-gal, 1250 mg/kg/d) and NaNO2 (90 mg/kg/d) for 8 weeks. OE (3 mg/kg/d, 15 mg/kg/d) was orally administered for 8 weeks, and the nootropic drug piracetam (PA, 400 mg/kg/d) was used as a positive control. A Morris water maze was used to assess cognitive ability. GSH and MDA levels and T-AOC, SOD, and CAT activities in the brain or plasma were determined. Hippocampal morphology was observed by HE staining, and expression of the anti-apoptotic protein Bcl-2 and the pro-apoptotic proteins Bax and Caspase-3 was observed by immunohistochemical staining.

RESULTS

Large-dosage treatments with D-gal/NaNO2 for 8 weeks significantly reduced survival, impaired spatial memory capacity, compensatorily up-regulated GSH level and T-AOC and SOD activities, decreased CAT activity, and induced hippocampal neuronal damage and apoptosis as reflected by the apparent low expression of Bcl-2 and high expression of Bax and Caspase-3. OE significantly prolonged lifespan and was more potent than PA. Similar to PA, OE at 15 mg/kg/d improved memory capacity. The underlying mechanism of action was related to the reversal of abnormal brain antioxidant biomarkers (GSH, T-AOC, and SOD) to normal levels and the inhibition of hippocampal neuronal apoptosis.

CONCLUSION

OE from P. oleracea is an active compound for improving cognitive function and is also a candidate nootropic drug for the treatment of age-related dementia.

Hierarchical ZnO Nanosheet-Nanorod Architectures for Fabrication of Poly(3-hexylthiophene)/ZnO Hybrid NO2 Sensor

A facile one-step solution method has been developed here to fabricate hierarchical ZnO nanosheet-nanorod architectures for compositing with poly(3-hexylthiophene) (P3HT) for fabricating a hybrid NO2 sensor. The hierarchical ZnO nanosheet-nanorod architectures were controllably synthesized by aging the solutions containing 0.05 mol·L(-1) Zn(2+) and 0.33 mol·L(-1) OH(-) at 60 °C through a metastable phase-directed mechanism. The concentration of OH(-) played a huge role on the morphology evolution. When the [OH(-)] concentration was decreased from 0.5 to 0.3 mol·L(-1), the morphology of the ZnO nanostructures changed gradually from monodispersed nanorods (NR) to nanorod assemblies (NRA), and then to nanosheet-nanorod architectures (NS-NR) and nanosheet assemblies (NSA), depending on the formation of various metastable, intermediate phases. The formation of NS-NR included the initial formation of ZnO nanosheets/γ-Zn(OH)2 mixed intermediates, followed by the dissolution of Zn(OH)2, which served as soluble zinc source. Soluble Zn(OH)2 facilitated the dislocation-driven secondary growth of ZnO nanorod arrays on the primary defect-rich nanosheet substrates. Hybrid sensors based on composite films composed of P3HT and the as-prepared ZnO nanostructures were fabricated for the detection of NO2 at room temperature. The P3HT/ZnO NS-NR bilayer film exhibited not only the highest sensitivity but also good reproducibility and selectivity to NO2 at room temperature. The enhanced sensing performance was attributed to the formation of the P3HT/ZnO heterojunction in addition to the enhanced adsorption of NO2 by NS-NR ZnO rich in oxygen-vacancy defects.

Vasculogenic mimicry and hypoxia-inducible factor-1α expression in cervical squamous cell carcinoma

In this study, the existence of vasculogenic mimicry (VM) in cervical squamous cell carcinoma was investigated. To this end, the relationship between hypoxia-inducible factor 1α (HIF-1α) and the development, infiltration, and metastasis of cervical squamous cell carcinoma was studied. Between January 2010 and December 2010, 67 human cervical squamous carcinoma tissue samples were collected and stained by CD34/periodic acid-Schiff double staining to detect the existence of VM. HIF-1α expression was analyzed by immunohistochemistry. The relationship between VM and HIF-1α was also analyzed. Normal cervical tissues (20 cases) from patients who had uterine surgeries in the same period were collected as controls. In the cervical squamous carcinoma tissues, positive rates of VM and HIF-1α were 38.81% (26/67) and 64.18% (43/67), respectively. This was significantly higher than those in the normal cervical tissues [0 (0/20); P < 0.05]. VM rates in cervical squamous carcinoma tissues from patients with different pathological grades, Federation of Gynecology and Obstetrics (FIGO) stages, and lymph node metastasis states were also significantly different (P < 0.05). In addition, significant differences in HIF-1α positivity rates were observed among patients with varying tumor sizes and lymph node metastasis states (P < 0.05). Positive correlation was found between VM and HIF-1α (r = 0.339, P < 0.05). To summarize, we found VM in cervical squamous carcinoma; high expression of HIF-1α may promote VM formation, as well as cervical squamous cell infiltration and metastasis.

Neuroprotective effects of an aqueous extract of Futokadsura stem in an Aβ-induced Alzheimer's disease-like rat model

Futokadsura stem has been traditionally used to dispel wind-damp obstruction syndrome manifested as painful and stiff joints, tendon and muscle spasms, lower back pain, painful knees and pain from external injury. An aqueous extract of Futokadsura stem has previously been found to have neuro-protective effects in vitro. In this study, we aimed to investigate if the Futokadsura stem extract could protect the neuron in the brain of an Aβ-induced Alzheimer's Disease (AD)-like rat model by improving the learning and memory ability of the rats. Learning and memory ability of the rats were measured by the Morris water maze test. Neuronal morphology in the hippocampus was examined by HE staining. Expression levels of Aβ, TNF-α, IL-6 and synaptophysin (SYP) were measured by immunofluorescence. Nitric oxide (NO) and nitric oxide synthase (NOS) levels were measured by NO and NOS detecting kit. We found that aqueous extract of Futokadsura stem alleviated Aβ(25-35)-induced impairment of spatial learning and memory in the AD rats. Furthermore, the extract protected the neurons by decreasing the expression of Aβ, TNF-α and IL-6 and the content of NO and NOS in the brain, and increasing the expression of SYP in the hippocampus. Our data indicated that aqueous extract of Futokadsura stem improved the learning and memory ability of AD rats. The neuro-protective effect was accomplished probably by depressing inflammation and oxidative stress in the brain.

Indoline Amide Glucosides from Portulaca oleracea: Isolation, Structure, and DPPH Radical Scavenging Activity

A polyamide column chromatography method using an aqueous ammonia mobile phase was developed for large-scale accumulation of water-soluble indoline amide glucosides from a medicinal plant, Portulaca oleracea. Ten new [oleraceins H, I, K, L, N, O, P, Q, R, S (1-10)] and four known [oleraceins A-D (11-14)] indoline amide glucosides were further purified and structurally characterized by various chromatographic and spectroscopic methods. The DPPH radical scavenging activities of oleraceins K (5) and L (6), with EC50 values of 15.30 and 16.13 μM, respectively, were twice that of a natural antioxidant, vitamin C; the EC50 values of the 12 other indoline amides, which ranged from 29.05 to 43.52 μM, were similar to that of vitamin C. Structure-activity relationships indicated that the DPPH radical scavenging activities of these indoline amides correlate with the numbers and positions of the phenolic hydroxy groups.

Timing of antiretroviral therapy initiation after diagnosis of recent human immunodeficiency virus infection and CD4(+) T-cell recovery

We retrospectively examined the timing of antiretroviral therapy (ART) initiation and CD4(+) T-cell recovery over 36 months among recent human immunodeficiency virus (HIV) infections using BED (HIV-1 subtypes B, E and D) immunoglobulin G capture enzyme immunoassay (BED-CEIA). Regardless of baseline CD4(+) counts, individuals (n = 393) who initiated ART >2 months after diagnosis had significantly decreased probability and rate of achieving CD4(+) counts ≥900 cells/μL or ≥600 cells/μL than those individuals (n = 135) who started ART earlier (≤2 months). But the mean CD4(+) counts in two groups converged after 30 months of treatment. Early ART initiation leads to accelerated CD4(+) recovery, but does not offer a long-term advantage in CD4(+) counts.

The effects of nerve growth factor on endothelial cells seeded on different titanium surfaces

Angiogenesis is critical for peri-implant bone regeneration and osseointegration. Endothelial cells (ECs) play an important role in angiogenesis during the early stage of bone formation. Nerve growth factor (NGF) is also reported to function as an angiogenic growth factor. The effects of NGF on ECs seeded on titanium surfaces are unclear. This study was done to investigate the influence of NGF on peri-implant angiogenesis in vitro and in vivo. We used two different titanium surfaces. ECs seeded on these surfaces were treated with indicated concentrations of NGF or vascular endothelial growth factor (VEGF). Proliferation, differentiation, morphological features, and amounts attached were assessed. Chicken embryo chorioallantoic membrane (CAM) was adopted to evaluate the effect of NGF in vivo. The results showed that NGF could promote EC proliferation on both titanium surfaces (F1d=2.083, P=0.156; F3d=30.857, P=0.0002; F5d=4.440, P=0.041; F7d=11.065, P=0.001). NGF and the SLA surface upregulated mRNA of NGF, TrkA, and p75 expression (FNGF=11.941, P=0.003; FTrkA=28.514, P=0.004; Fp75=7.725, P=0.01). In vivo, the supernatants of the NGF-treated group could promote neovascularization in CAM (F=17.662, P=0.009). This study demonstrated that NGF could enhance EC proliferation, gene expression on different titanium surfaces, and neovascularization in CAM. This provides novel information in relation to the promotion of early dental implant osseointegration.

Neuritogenic Activity of Tetradecyl 2,3-Dihydroxybenzoate Is Mediated through the Insulin-Like Growth Factor 1 Receptor/Phosphatidylinositol 3 Kinase/Mitogen-Activated Protein Kinase Signaling Pathway

Tetradecyl 2,3-dihydroxybenzoate (ABG-001) is a lead compound derived from neuritogenic gentisides. In the present study, we investigated the mechanism by which ABG-001 induces neurite outgrowth in a rat adrenal pheochromocytoma cell line (PC12). Inhibitors of insulin-like growth factor 1 (IGF-1) receptor, phosphatidylinositol 3-kinase (PI3K), and extracellular signal-regulated kinase (ERK) 1/2 significantly decreased ABG-001-induced neurite outgrowth. Western blot analysis revealed that ABG-001 significantly induced phosphorylation of IGF-1 receptor, protein kinase B (Akt), ERK, and cAMP responsive element-binding protein (CREB). These effects were markedly reduced by addition of the corresponding inhibitors. We also found that ABG-001-induced neurite outgrowth was reduced by protein kinase C inhibitor as well as small-interfering RNA against the IGF-1 receptor. Furthermore, like ABG-001, IGF-1 also induced neurite outgrowth of PC12 cells, and low-dose nerve growth factor augmented the observed effects of ABG-001 on neurite outgrowth. These results suggest that ABG-001 targets the IGF-1 receptor and activates PI3K, mitogen-activated protein kinase, and their downstream signaling cascades to induce neurite outgrowth.

Supersaturation-induced hydrothermal formation of α-CaSO4·0.5H2O whiskers

Supersaturation-induced fast transformation from CaSO₄·2H₂O to α-CaSO₄·0.5H₂O was observed and the process followed the dissolution–precipitation and homogeneous nucleation mechanism according to classical nucleation theory.

Plasma metabolic signatures reveal the regulatory effect of exercise training in db/db mice

Regulatory effect of moderate exercise training on fatty acid oxidation.