Biphasic 2-methyltetrahydrofuran/oxalic acid/water pretreatment to enhance cellulose enzymatic hydrolysis and lignin valorization.

A biphasic pretreatment was adopted to disturb the recalcitrant structure of bamboo for further enzymatic hydrolysis and to obtain easily valorized lignin by-product. The biphasic system consisted of biomass-derived chemicals-2-methyltetrahydrofuran and oxalic acid as well as water, and the reactions were conducted at 120-180°C for 20min. The treatment resulted in notable removal of hemicelluloses and lignin. After the pretreatment, the cellulose conversion rate during enzymatic hydrolysis was enhanced by 6.7-fold as compared to the unpretreated raw material. Comprehensive analysis of the lignin product indicated that it exhibited representative structure (such as ß-O-4, ß-ß linkages) as compared to native lignin, contained a very low amount of contaminated sugars (0.67-2.39%), and had a relatively medium molecular weight (Mw 2240-3730g/mol) and good solubility in many organic solvents. This indicated that the lignin showed great potential application in conversion into materials and liquid fuels.

Microwave-Assisted Hydrothermal Synthesis of Cellulose/Hydroxyapatite Nanocomposites.

In this paper, we report a facile, rapid, and green strategy for the synthesis of cellulose/hydroxyapatite (HA) nanocomposites using an inorganic phosphorus source (sodium dihydrogen phosphate dihydrate (NaH2PO4·2H2O)), or organic phosphorus sources (adenosine 5'-triphosphate disodium salt (ATP), creatine phosphate disodium salt tetrahydrate (CP), or D-fructose 1,6-bisphosphate trisodium salt octahydrate (FBP)) through the microwave-assisted hydrothermal method. The effects of the phosphorus sources, heating time, and heating temperature on the phase, size, and morphology of the products were systematically investigated. The experimental results revealed that the phosphate sources played a critical role on the phase, size, and morphology of the minerals in the nanocomposites. For example, the pure HA was obtained by using NaH2PO4·2H2O as phosphorus source, while all the ATP, CP, and FBP led to the byproduct, calcite. The HA nanostructures with various morphologies (including nanorods, pseudo-cubic, pseudo-spherical, and nano-spherical particles) were obtained by varying the phosphorus sources or adjusting the reaction parameters. In addition, this strategy is surfactant-free, avoiding the post-treatment procedure and cost for the surfactant removal from the product. We believe that this work can be a guidance for the green synthesis of cellulose/HA nanocomposites in the future.

[Safety and efficacy of transradial percutaneous coronary intervention for unprotected left main coronary artery lesions with 6 French guiding catheter].

OBJECTIVE: To investigate the safety, medium-term and long-term efficacy of transradial percutaneous coronary intervention for unprotected left main coronary artery lesions with 6 French guiding catheter. METHODS: Sixty-one patients with unprotected left main coronary artery lesions were treated by 6 French transradial percutaneous coronary intervention between January 2008 and December 2009. The mean age of patients was (66.03 ±10.02)years (44-87). Among 61 cases, 40 had hypertension and 14 had diabetes mellitus; 22 had a history of smoking. The average left ventricle ejection fraction was (62.96 ±12.15)% (range: 28-86) and the average plasma creatinine level was (82.92 ±18.30)µmol/L (range: 44-130). The major adverse cardiac events (MACE) after the procedure were evaluated. RESULTS: Procedural success was achieved in all cases. A total of 67 stents were implanted. No in-hospital death occurred. Mean clinical follow-up period was (26.25 ±5.92) months (range: 19-44 months). MACE developed in 6 cases (9.8%) during the follow-up period, including 2 death (3.3%) and 4 case of target lesion revascularization (6.6%). Compared with low-risk group (SYNTAX score<33), MACE was increased in the high-risk group (SYNTAX score>32). CONCLUSION: 6 French transradial percutaneous coronary intervention for patients with unprotected left main coronary artery lesions is safe and feasible procedure with desirable medium-and long-term outcomes.

Abnormal neural activity of brain regions in treatment-resistant and treatment-sensitive major depressive disorder: a resting-state fMRI study.

BACKGROUND: Patients with treatment-resistant depression (TRD) and those with treatment-sensitive depression (TSD) responded to antidepressants differently. Previous studies have commonly shown that patients with TRD or TSD had abnormal neural activity in different brain regions. In the present study, we used a coherence-based ReHo (Cohe-ReHo) approach to test the hypothesis that patients with TRD or TSD had abnormal neural activity in different brain regions. METHODS: Twenty-three patients with TRD, 22 with TSD, and 19 healthy subjects (HS) matched with gender, age, and education level participated in the study. RESULTS: ANOVA analysis revealed widespread differences in Cohe-ReHo values among the three groups in different brain regions which included bilateral superior frontal gyrus, bilateral cerebellum, left inferior temporal gyrus, left occipital cortex, and both sides of fusiform gyrus. Compared to HS, lower Cohe-ReHo values were observed in TRD group in bilateral superior frontal gyrus and left cerebellum; in contrast, in TSD group, lower Cohe-ReHo values were mainly found in bilateral superior frontal gyrus. Compared to TSD group, TRD group had lower Cohe-ReHo in bilateral cerebellum and higher Cohe-ReHo in left fusiform gyrus. There was a negative correlation between Cohe-ReHo values of the left fusiform gyrus and illness duration in the pooled patients (r = 0.480, p = 0.001). The sensitivity and specificity of cerebellar Cohe-ReHo values differentiating TRD from TSD were 83% and 86%, respectively. CONCLUSIONS: Compared to healthy controls, both TRD and TSD patients shared the majority of brain regions with abnormal neural activity. However, the lower Cohe-ReHo values in the cerebellum might be as a marker to differentiate TRD from TSD with high sensitivity and specificity.

Altered white matter integrity in young adults with first-episode, treatment-naive, and treatment-responsive depression.

Abnormalities of the white matter (WM) tracts integrity in brain areas involved in emotional regulation have been postulated in major depressive disorder (MDD). However, there is no diffusion tensor imaging (DTI) study in patients with treatment-responsive MDD at present. DTI scans were performed on 22 patients with treatment-responsive MDD and 19 well-matched healthy subjects. Tract-based spatial statistics (TBSS) approach was employed to analyze the scans. Voxel-wise statistics revealed four brain WM tracts with lower fractional anisotropy (FA) in patients compared to healthy subjects: the bilateral internal capsule, the genu of corpus callosum, the bilateral anterior corona radiata, and the right external capsule. FA values were nowhere higher in patients compared to healthy subjects. Our findings demonstrate that the abnormalities of the WM tracts, major in the projection fibers and corpus callosum, may contribute to the pathogenesis of treatment-responsive MDD.

Breviscapine inhibits high glucose-induced proliferation and migration of cultured vascular smooth muscle cells of rats via suppressing the ERK1/2 MAPK signaling pathway.

AIM: To investigate the influences of breviscapine, a flavonoid extracted from Erigeron breviscapus, on the proliferation and migration of vascular smooth muscle cells (VSMCs) cultured in a high glucose medium and the underlying mechanisms. METHODS: VSMCs were isolated from thoracic aortas of male Sprague-Dawley rats and cultured in vitro. Cell proliferation was evaluated using Counting Kit-8 cell viability assay. Cell migration was evaluated using transwell migration assay and in vitro scratch assay. The expression and activity of protein kinase C-ß2 (PKC-ß2), extracellular signal-regulated kinase 1/2 (ERK1/2), p38 mitogen-activated protein kinase (p38), and JNK mitogen-activated protein kinase (JNK) were measured with Western blotting. RESULTS: Exposure of VSMCs to a high glucose (25 mmol/L) medium significantly increased the proliferation and migration potential as compared to the control group. Pretreatment with breviscapine (65 µmol/L and 108 µmol/L) attenuated high glucose-enhanced proliferation and migration of VSMCs. Exposure of VSMCs to the high glucose medium activated both the PKC-ß2 and ERK1/2 MAPK, but not the p38 and JNK MAPK. Pretreatment with breviscapine (65 µmol/L and 108 µmol/L) blocked high glucose-induced increase of the ERK1/2 activity, but not that of the PKC-ß2 activity. CONCLUSION: Our study demonstrated that breviscapine ameliorates high glucose-induced proliferation and migration of VSMCs via inhibiting ERK1/2 MAPK signaling.

Alterations of the amplitude of low-frequency fluctuations in treatment-resistant and treatment-response depression: a resting-state fMRI study.

BACKGROUND: Patients with treatment-resistant depression (TRD) and those with treatment-response depression (TSD) respond to antidepressants differently and previous studies have commonly reported different brain networks in resistant and nonresistant patients. Using the amplitude of low-frequency fluctuations (ALFF) approach, we explored ALFF values of the brain regions in TRD and TSD patients at resting state to test the hypothesis of the different brain networks in TRD and TSD patients. METHODS: Eighteen TRD patients, 17 TSD patients and 17 gender-, age-, and education-matched healthy subjects participated in the resting-state fMRI scans. RESULTS: There are widespread differences in ALFF values among TRD patients, TSD patients and healthy subjects throughout the cerebellum, the visual recognition circuit (middle temporal gyrus, middle/inferior occipital gyrus and fusiform), the hate circuit (putamen), the default circuit (ACC and medial frontal gyrus) and the risk/action circuit (inferior frontal gyrus). The differences in brain circuits between the TRD and TSD patients are mainly in the cerebellum, the visual recognition circuit and the default circuit. CONCLUSIONS: The affected brain circuits of TRD patients might be partly different from those of TSD patients.

Abnormal neural activities in first-episode, treatment-naïve, short-illness-duration, and treatment-response patients with major depressive disorder: a resting-state fMRI study.

BACKGROUND: Abnormality of limbic-cortical networks was postulated in depression. Using a regional homogeneity (ReHo) approach, we explored the regional homogeneity (ReHo) of the brain regions in patients with first-episode, treatment-naïve, short-illness-duration, and treatment-response depression in resting state to test the abnormality hypothesis of limbic-cortical networks in major depressive disorder (MDD). METHODS: Seventeen patients with treatment-response MDD and 17 gender-, age-, and education-matched healthy subjects participated in the resting-state fMRI scans. CONCLUSIONS: Our findings suggested the abnormality of limbic-cortical networks in first-episode, treatment-naïve, short-illness-duration, and treatment-response MDD patients, and added an expanding literature to the abnormality hypothesis of limbic-cortical networks in MDD.

Dopamine D4 receptor gene exon III polymorphism and interindividual variation in response to clozapine.

To investigate the relationship between 48 bp variant number tandem repeat polymorphism in dopamine D4 receptor gene and response to clozapine in schizophrenic patients, the authors included 81 inpatients with a DSM-IV diagnosis of schizophrenia and patients meeting criteria for refractory to treatment were excluded. This study found that the frequencies of five 48 bp repeats homozygous genotype and five 48 bp repeats allele were significantly less in the responders than the nonresponders, which divided by improving total schizophrenic symptom. The results of this study suggest that inherited variants of D4 may explain some of the interindividual variation seen in patient response to clozapine.