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Our previous work showed that for catalytic alkylation of m-cresol with tert-butanol (TBA) S0 3 H-functionalized ionic liquids exhibited several characteristic advantages over conventional catalysts. This work investigated the reaction mechanism of the alkylation of m-cresol with tert-butanol catalyzed by the S0 3 H-functionalized ionic liquid (IL) through quantum chemical calculation in combination with the experimental studies. The experimental results showed that 2-tert-butyl-5-methyl phenol (2-TBC), 4-tert-butyl-3-methyl phenol (4-TBC) and tert-butyl-m-cresol ether (TBMCE) products were all primary products, while 2,6-di-tert-butyl-3-methyl phenol (2,6-DTBC) was a secondary product. The calculation results indicated that the selectivities of the products depended on the fundamental natures of the reactive sites, including the orbital overlap, the Coulomb and the steric effect in the interaction between the tert-butyl ion ([t-C 4 H 9 ] + ) and the m-cresol; the TBMCE was dynamically favored but not thermodynamically stable, while the C-alkylated products, especially 2-TBC, were the thermodynamically preferred products; the IL played an important role in generating the [t-C 4 H 9 ] + from the TBA and the final products from the intermediates.

Supported Cu catalysts were synthesized and applied to convert glycerol, a renewable feedstock, to value-added propanediols. Among these catalysts, the γ-Al 2 O 3 supported Cu catalysts showed superior performance. Unlike most supported precious metal catalysts, the scission of C–C bonds was successfully suppressed on the Cu/Al 2 O 3 catalysts without a sacrifice of glycerol conversion. The experimental results combined with the characterization studies using temperature programmed reduction (TPD) and X-ray diffraction (XRD) techniques revealed that the optimal Cu loading was 2.7 mmol of Cu metal/g of γ-Al 2 O 3 and that the suitable pre-reduction temperature was 300 °C. The Cu/Al 2 O 3 catalyst with the optimized amount of Cu showed a selectivity to propanediols about 96.8% with a glycerol conversion about 49.6% under mild reaction conditions (220 °C, 1.5 MPa initial H 2 pressure, 10 h, Cu/glycerol molar ratio 3:100). Compared with a commonly used commercial copper chromite catalyst, the Cu/Al 2 O 3 presented much higher activity, selectivity and Cu usage efficiency and is non-toxic.

Background Schistosoma japonicum is the most widespread schistosoma in the world. Although gastrointestinal system involvement with S japonicum appears to be considerably common, cerebral schistosomiasis is not frequent. Cerebral schistosomiasis japonica intestinal and hepatosplenic involvement is more rare. We collected 2 cases of cerebral schistosomiasis identified by pathological diagnosis, lacking extracranial involvement. In addition, one of them had multiple lesions, which was also rare. Case Description Two male patients came from Dongting Lake region, Hunan province, one of the oldest and most severe endemic areas of China. Their clinical symptoms varied, such as headache, dizziness, seizures, and others. Studies in blood were normal except for eosinophilia. Computed tomography of brains showed hyperdense areas, and MRI showed isointense signal on T1-weighted images, hyperintense signal on T2-weighted images, and heterogeneous enhancement. The definitive diagnosis was cerebral schistosomiasis japonium by biopsy. Standard use of praziquantel and corticosteroid drugs was applied, and the prognosis was good. Conclusion Cerebral schistosomiasis japonica without intestinal and hepatosplenic involvement is exactly rare and easily ignored. The diagnosis sometimes is difficult. Laboratory and imaging examinations are helpful but not specific. Although operation can give the definitive diagnosis, it is not imperative. The administration of praziquantel and corticosteroid drugs in early stages is good for prognosis.

A commercial Beta-type zeolite was studied for upgrading unsaturated fatty acids, a renewable feedstock. Catalyst calcination and additive addition were investigated aiming to improve the catalytic activity for the skeletal isomerization of oleic acid. Calcination at a temperature around 450 °C instead of the commonly used 550 °C generated catalysts with relatively low surface areas but high activities, which is attributed to the high Bronsted acidity as revealed by FTIR characterization. Addition of a small amount of water (2–5 wt% of fatty acid) to the fatty acid promoted the conversion, but any further increase in the amount of water would result in a catalytic activity loss. Although methanol did not show a promoting effect for the isomerization, the methyl ester of oleic acid showed a higher conversion than oleic acid on the same catalyst. The poisoning effect of the carboxylic group on oleic acid was demonstrated by the comparison of the isomerization reactions of oleic acid and 1-octadecene.

The catalytic performance of anion modified zirconia catalysts, such as sulfated zirconia (SO4/ZrO2) and tungstated zirconia (WO3/ZrO2), was evaluated for the upgrading of oleic acid (OA). In the presence of an aromatic compound, two main reactions occurred on the catalysts: the skeletal isomerization of OA and the arylation of OA with aromatics. The activity of the SO4/ZrO2 was more than triple of that of the WO3/ZrO2. At 250 °C, OA/(SO4/ZrO2)(wt/wt) = 5, the OA conversion and the arylation selectivity reached their maximal values and the isomerization selectivity was the lowest when the toluene to OA (toluene/OA) molar ratio was about 6. When mesitylene was used instead of toluene, the OA conversion and the arylation selectivity decreased, probably because of a steric effect. An attempt to reuse the SO4/ZrO2 by solvent washing after a run was not so successful, while calcination at 630 °C in air recovered the activity completely.

Activated carbons have been prepared from petroleum cokes by the combination of a chemical treatment with HClO4 or H2O2 and a chemical activation with KOH at a constant KOH/coke ratio of 3/1. The influence of different chemical treatments on the properties of the activated carbon precursors and final carbons activated with KOH was invested by using XRD, FTIR, and BET techniques. XRD results indicated that the value of interplanar distance d002 increased by chemical treatment and the disappearance of the peak corresponding to 0 0 2 faces correlated to high specific surface area. FTIR studies showed that chemical modification promoted the formation of surface oxygen functionalities. Significant effects on BET surface area, pore texture and iodine adsorption capacity were evidenced. The results show that chemical modification prior to activation dramatically increased the BET surface area and total pore volume of the resulting activated carbon. Modified petroleum coke based activated carbon with chemical activation had higher specific surface area (2336 m2/g) and better iodine adsorption value (1998 mg/g).

Paroxysmal kinesigenic dyskinesia (PKD) is a rare neurologic inherited disease with heterogeneity. Autosomal dominant (AD) is the common inherited mode. There have been two loci mapped to 16 chromosome for PKD. However, no gene responsible for it has been identified so far. We collected 6 pedigrees from Chinese mainland. There were 122 members in all, including 26 affected. According to New diagnostic criteria of Bruno, they were diagnosed as pure PKD. From the clinic data, we found that the onset age was earlier and the severity was increasing in the subsequent generations in 4 pedigrees of them, which suggested genetic anticipation. Linkage analysis was applied in 2 of these pedigrees. The maximum LOD score and NPL score were negative. The followed haplotypes analysis excluded the PKD locus in both families from chromosome 16, providing evidence for a novel locus.

The SO3H-functionalized ionic liquids were synthesized by using pyridine and 1,4-butane or 1,3-propane sulfone as the source and characterized by NMR and time-of-flight mass spectrometry. The acidity of the ionic liquids determined by the Hammett method is almost the same as that of a conventional acid, such as H2SO4. The catalytic performance of ionic liquids for the tert-butylation of p-cresol with tert-butanol was evaluated; by using the ionic liquids as catalysts at the optimum reaction conditions, 79% of the p-cresol conversion and 92% of the selectivity to 2-tert-butyl-p-cresol can be obtained. The spent ionic liquid can be recovered and recycled. The possible mechanism for this reaction system was discussed based on the reaction results and the ab initio calculation results.

The SO 3 H-functionalized ionic liquids were synthesized by using tri-alkylamine and 1,4-butanesultone as the source, and characterized by NMR and TOF-MS, and their catalytic performance for the tert -butylation of m-cresol with tert -butanol (TBA) were investigated. The reaction time, reaction temperature, molar ratio of m-cresol to TBA, and the recycle number of the spent ionic liquid were examined. Under optimum reaction conditions, the conversion of m-cresol and the selectivity to 2- tert -butyl-5-methyl phenol (2-TBC) were 81% and 96%, respectively. No apparent loss of activity and selectivity of the ionic liquid were observed after four recycles. The acidity of ionic liquids determined by Hammett method is about the same as that of conventional acid, such as H 2 SO 4 . The possible mechanism for this reaction system was discussed based on the reaction results and the ab initio calculation results.

Summary Aim To assess the efficacy and safety of dipeptidyl peptidase 4-inhibitors (DPP4-I) compared with sulphonylureas in adults with type 2 diabetes (T2D) mellitus. Method Randomised controlled trials were collected from PubMed, EMBASE, Google Scholar and conference. The primary outcome was the change in HbA1c. Secondary outcomes included weight gain, the change in postprandial plasma glucose (PPG), insulin resistance and fasting plasma glucose (FPG), adverse event (AE) and incidence of hypoglycaemia. Results Fourteen studies including 5480 patients randomised to DPP4-I and 5214 patients randomised to sulphonylureas were eligible for the meta-analysis. Compared with sulphonylureas, DPP4-I were associated with a smaller decline in HbA1c (WMD, weighted mean differences 0.08%, 95% CI: 0.03–0.14, p = 0.001), and resulted in weight loss of 1.945 kg (95% CI: −2.237 to −1.653, p < 0.0001). The effect of DPP4-I lowering FPG was inferior to that of sulfonylureas (WMD, 0.268 mmol/l, 95% CI, 0.151–0.385, p < 0.0001), and similar in reducing PPG (WMD, 0.084, 95% CI, −0.701 to 0.869, p = 0.833). According to the follow-up period, the included trials were separated into three groups (group 1: less than half one year, group 2: from half one year to 1 year, group 3: more than 1 year). Subgroup analysis showed that the difference in HbA1c between DPP4-I and sulphonylureas presented a decline curve (group 1: 0.50, 95% CI: 0.15–0.84, group 2: 0.05, 95% CI: −0.05 to 0.15, group 3: 0.09, 95% CI: 0.03–0.15). DPP4-I had a favourable insulin resistance compared with sulfonylureas (WMD, −0.673, 95% CI, −1.248 to −0.097, p = 0.022). In addition, compared with sulfonylureas, DPP4-I was associated with a decrease in overall risk for AE (RR, 0.93, 95% CI, 0.91–0.96, p < 0.0001). The incidence of hypoglycaemia was lower with DPP4-I (RR, 0.24, 95% CI, 0.21–0.27, p < 0.001). Conclusion Patients with T2D who receive DPP4-I could achieve almost similar glycaemic targets with sulphonylureas, with favourable effects on body weight and lower incidence of hypoglycaemia.

The catalytic hydrogenolysis of readily available glycerol to 1,2-propanediol (1,2-PD) and 1,3-propanediol (1,3-PD), which provides a new promising synthesis route to produce propanediols, has been extensively studied in the past decades. This study summarizes the most significant reports regarding glycerol hydrogenolysis into propanediols. Three reaction routes, including those working towards 1,2-PD production and the recently proposed one leading to 1,3-PD production, have been summarized. The catalysts used for this reaction have been classified into two categories according to the type of metal components: the transition metal catalysts taking Cu, Ni, and Co as representative metal components and the noble metal catalysts containing Ru, Pt, Ir, and Ag. Some inexpensive transition-metal catalysts exhibit high 1,2-PD selectivity and yield under mild reaction conditions, whereas several noble metal catalysts are promising in synthesizing the more valuable 1,3-PD. Efficient preparation methods and precise modulation techniques have been systematically developed to synthesize functionalized catalysts on the basis of the metal species in combination with acidic or basic compounds. Other technological aspects, such as hydrogen sources, reaction solvents, reactor types and feeding processes, are also summarized in this study. The focus of this review is on summarizing the preparation methods and the performance of various catalysts in glycerol hydrogenolysis.

Removal of C2H4 from a CO2 stream is very important in ultrapurification of CO2 for its application and utilization. However, it is difficult to remove C2H4 completely from a CO2 stream via conventional cryogenic distillation because the volatility of C2H4 is similar to that of CO2. Another choice is the catalytic combustion method, but it is an energy-inefficient process, especially when it is coupled with the cryogenic distillation. Selective adsorption for removing C2H4 might be a promising alternative. A great effort has been made in C2H4/C2H6 separation and recovery of C2H4. There were, however, few reports about the removal of a trace amount of C2H4 from a CO2 stream. In this study, the AgNO3-modified NaY and HY zeolites are prepared and their adsorption performances are evaluated via a series of experiments of fixed-bed adsorption, frontal chromatographic adsorption, and temperature-programmed desorption (TPD). The structure of the sliver salt after being impregnated onto the supports has been char...

Removal of C2H4 from a CO2 stream is very important in ultrapurification of CO2 for its application and utilization. However, it is difficult to remove C2H4 completely from a CO2 stream via conventional cryogenic distillation because the volatility of C2H4 is similar to that of CO2. Another choice is the catalytic combustion method, but it is an energy-inefficient process, especially when it is coupled with the cryogenic distillation. Selective adsorption for removing C2H4 might be a promising alternative one. A great effort has been made in olefin/paraffin separation and recovery of olefin. There are, however, few reports about the removal of a trace of C2H4 from a CO2 stream. In this study, ab initio calculations have been conducted to screen the potential adsorbents. We found that AgNO3 exhibits a much higher adsorption affinity for C2H4 through a π-complexation interaction, indicating that the AgNO3-modified zeolite might be a promising adsorbent. Furthermore, the AgNO3-modified NaY zeolite was prepar...

Substantial evidence implicates abnormal protein kinase function in various aspects of Parkinson’s disease (PD) etiology. Elevated phosphorylation of the PD-defining pathological protein, α-synuclein, correlates with its aggregation and toxic accumulation in neurons, whilst genetic missense mutations in the kinases PTEN-induced putative kinase 1 (PINK1) and leucine-rich repeat kinase 2 (LRRK2), increase susceptibility to PD. Experimental evidence also links kinases of the phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signaling pathways, amongst others, to PD. Understanding how the levels or activities of these enzymes or their substrates change in brain tissue in relation to pathological states can provide insight into disease pathogenesis. Moreover, understanding when and where kinase dysfunction occurs is important as modulation of some of these signaling pathways can potentially lead to PD therapeutics. This review will summarize what is currently known in regard to the expression of these PD-implicated kinases in pathological human postmortem brain tissue.

Summary Background and aims Tenuigenin (Ten) is a Chinese herbal extract with antioxidative and antiinflammatory effects on toxin-induced cell models of Parkinson's disease (PD); however, its effects on α-synuclein toxicity-based PD models remain unknown. α-synuclein hyperphosphorylation is a key event in PD pathogenesis and potential target of therapeutic interventions. We tested whether Ten alleviates α-synuclein-induced cytotoxicity via reducing kinases that phosphorylate α-synuclein. Methods SH-SY5Y cells transiently transfected with wild-type or A53T mutant α-synuclein were used to evaluate the effect of Ten on the levels of α-synuclein phosphorylation-related kinases. Cells treated with 10 μM Ten for 24 h were measured for viability (proliferation and apoptosis assays) and cellular proteins harvested and fractioned. The levels of total and phosphorylated α-synuclein and five associated kinases (polo-like kinase [PLK] 1–3, casein kinase [CK] 1–2) were evaluated by Western blotting. Results Overexpression of either wild-type or A53T mutant α-synuclein decreased cell viability and increased α-synuclein phosphorylation. Ten treatment-protected cells from this α-synuclein-induced toxicity and dramatically reduced α-synuclein phosphorylation and PLK3 (but not other kinase) levels. Conclusion In α-synuclein cell model of PD, Ten is effective in attenuating α-synuclein-induced toxicity and α-synuclein phosphorylation probably via targeting PLK3, suggesting it could be an efficient therapeutic drug to treat α-synuclein-related neurodegeneration.

Lewy bodies are made from insoluble, phosphorylated α-synuclein, but the earliest changes that precipitate such pathology still remain conjecture. In this study, we quantify and identify relationships between the levels of the main pathologic form of phosphorylated α-synuclein over the course of Parkinson’s disease in regions affected early through to end-stage disease. Brain tissue samples from 33 cases at different disease stages and 13 controls were collected through the Australian Network of Brain Banks. 500 mg of frozen putamen (affected preclinically) and frontal cortex (affected late) was homogenized, fractionated and α-synuclein levels evaluated using specific antibodies (syn-1, BD Transduction Laboratories; S129P phospho-α-synuclein, Elan Pharmaceuticals) and quantitative western blotting. Statistical analyses assessed the relationship between the different forms of α-synuclein, compared levels between groups, and determined any changes over the disease course. Soluble S129P was detected in controls with higher levels in putamen compared with frontal cortex. In contrast, insoluble α-synuclein occurred in Parkinson’s disease with a significant increase in soluble and lipid-associated S129P, and a decrease in soluble frontal α-synuclein over the disease course. Increasing soluble S129P in the putamen correlated with increasing S129P in other fractions and regions. These data show that soluble non-phosphorylated α-synuclein decreases over the course of Parkinson’s disease, becoming increasingly phosphorylated and insoluble. The finding that S129P α-synuclein normally occurs in vulnerable brain regions, and in Parkinson’s disease has the strongest relationships to the pathogenic forms of α-synuclein in other brain regions, suggests a propagating role for putamenal phospho-α-synuclein in disease pathogenesis.

Heroin-induced leukoencephalopathy is a rare complication of heroin intoxication, and always presents as hypoxic ischemic leukoencephalopathy with periventricular white matter edema and spongiform leukoencephalopathy in cerebral and cerebellar white matter [1, 2]. Acute hydrocephalus following toxic leukoencephalopathy has been reported in carbon monoxide and methadone intoxication [3, 4]. However, acute hydrocephalus following heroininduced leukoencephalopathy has not been previously reported. On 14 April 2011, a 37-year-old man found in a hotel presented to our hospital after 1 day of unconsciousness. The rubbish can in the man’s hotel room contained an empty syringe, and there were several needle holes in his forearm. Physical examination showed neck rigidity. Glasgow score on admission was 7/15 (E = 1/4, V = 3/5, M = 3/6). His personal and family history was negative for diabetes, seizure disorders, alcohol abuse, and vascular risk factors. There was no evidence of carbon monoxide poisoning. Hematological and biochemical examinations including hepatitis B, C virus and HIV serology were normal except for high levels of blood creatine kinase (847.24 U/L) and myoglobin (193 lg/L). Drug screening in urine showed positive for heroin. Lumbar puncture showed mildly increased intracranial pressure of 200 mmH2O, and cerebrospinal fluid routine test and biochemistry were negative. A magnetic resonance imaging (MRI) of the brain revealed abnormally low signal intensity in T1-weighted and high signal intensity in T2-weighted images in bilateral cerebellar hemispheres (Fig. 1a). No abnormality was found in the cerebral magnetic resonance angiography. Toxic leukoencephalopathy was suspected. Mannitol and dexamethasone were administered, and the man became confused on the second day. Surprisingly, a repeat MRI of the brain on the fifth day revealed enlarged lesions in the bilateral cerebellar hemispheres and compression in the fourth ventricle (Fig. 1b), and diffusion weighted image (DWI) showed a high signal intensity in the bilateral cerebellar hemispheres (Fig. 1c). The man fell into a coma accompanied by dyspnea on the seventh day of admission. A computed tomography (CT) of the brain showed hypodense lesions in bilateral cerebellar hemispheres, the fourth ventricle vanishing, and dilatation of the lateral and third ventricles, indicating acute obstructive hydrocephalus (Fig. 1d). Tracheotomy and surgical external drainage of the hydrocephalus were applied, the consciousness and respiration recovered on the twentieth day while the ataxia and pyramidal signs remained. A brain CT showed that the hydrocephalus was improved (Fig. 1e). The man admitted to 1 year of heroin abuse by intranasal and intravenous administration about 1–3 g a day and confirmed that he had injected an extensive quantity of heroin on the day of onset. This pattern confirmed the diagnosis of acute heroin intoxication accompanied with leukoencephalopathy and acute hydrocephalus. Following a month of treatment, his symptoms were resolved and the imaged lesions were absorbed (Fig. 1f). To the best of our knowledge, this report is the first description of acute hydrocephalus in heroin-induced H. Long J. Zhou X. Zhou Y. Xie B. Xiao (&) Neurology Department, Xiangya Hospital Central-south University, Changsha 410008, China e-mail: csulhy@yahoo.cn

Supported Cu-containing bimetallic catalysts were prepared and used to convert glycerol to propanediols. The effects of supports, metals, metal loadings, and impregnation sequences were examined. A synergistic effect was observed between Cu and Ag when they were impregnated on γ-Al2O3. Characterizations revealed that the addition of Ag not only resulted in an in situ reduction of CuO, but also improved the dispersion of the Cu species on the support. A CuAg/Al2O3 catalyst with optimal amounts of Cu and Ag (Cu/Ag molar ratio 7 : 3, 2.7 mmol Cu+Ag per gram of γ-Al2O3) showed a near 100% selectivity to propanediols with a glycerol conversion of about 27% under mild reaction conditions (200 °C, 1.5 MPa initial H2 pressure, 10 h, (Cu+Ag)/glycerol molar ratio of 3/100). Compared with a commercial copper chromite catalyst commonly used for this reaction, the CuAg/Al2O3 catalyst had much higher activity and did not need a reduction pretreatment.