A number of SO3H-functionalized solids (biochar, montmorillonites, carbon and halloysite nanotubes) has been studied as catalysts in the cascade Prins-Ritter reaction of (-)-isopulegol with ...benzaldehyde and acetonitrile for synthesis of octahydro-2H-chromene amides (as 4R- and 4S-isomers). A high selectivity to these products at 30 °C in the presence of H2O was observed on catalysts modified with chlorosulfonic acid (CSA) reaching 84% (4R/4S of 5.7) in the case of biochar, while a relatively large amount of octahydro-2H-chromenols (up to 31%), products of Prins condensation, was formed on the materials functionalized by 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane (CSP). Although Prins condensation proceeds efficiently on weak acid sites, the Prins-Ritter reaction requires sulfated materials with strong (0.33 – 5.8 mmol/g) Brønsted acidity. Catalysts functionalized by CSP were stable, while for the materials modified with chlorosulfonic acid, leaching of -SO3H groups was observed. Nonetheless, on resistant Bioсhar-CSP, selectivity to the amides at 30 °C (67%) was higher than that with the commercial Amberlyst-15 (47%), and triflic acid at − 25 °C (62%). Similar selectivity to the desired products on Biochar-CSA (-SO3H groups) and H2SO4 (81–84%) as well as on Biochar-CSP (-PhSO3H) and with p-toluenesulfonic acid (67–70%) was observed. DFT calculations and experimental results showed that at 30 °C formation of 4S-amide thermodynamically is more beneficial than of alcohols and dehydration products. However, addition of water results in a sharp increase in the reaction rate and 4R-amide selectivity due to a change to the kinetic control, leading eventually to both high yields and stereoselectivity. The proposed reaction pathways also were confirmed by kinetic modelling.
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•Heterogeneous and homogeneous catalysts for the Prins-Ritter reaction at ambient conditions.•The reaction requires sulfated materials with strong Brønsted acidity.•Selectivity to amides up to 84% (4 R/4 S of 5.7) on Biochar-CSA or sulfuric acid.•Formation of 4S-amide is thermodynamically more favorable.•Addition of water results in a kinetic control with high stereoselectivity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Tensile strain along the cR axis in epitaxial VO sub(2) films raises the temperature of the metal insulator transition and is expected to stabilize the intermediate monoclinic M2 phase. We employ ...surface-sensitive x-ray spectroscopy to distinguish from the TiO sub(2) substrate and identify the phases of VO sub(2) as a function of temperature in epitaxial VO sub(2)/TiO sub(2) thin films with well-defined biaxial strain. Although qualitatively similar to our Landau-Ginzburg theory predicted phase diagrams, the M2 phase is stabilized by nearly an order of magnitude more strain than expected for the measured temperature window. Our results reveal that the elongation of the c sub()Raxis is insufficient for describing the transition pathway of VO sub(2) epitaxial films and that a strain induced increase of electron correlation effects must be considered.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We applied proteomics technologies to analyze the cerebrospinal fluid of patients with schizophrenia. Such an analysis can result in the identification of proteins, which may play a role in the ...disease progress and thus lead to the discovery of clues of the etiology of schizophrenia. Cerebrospinal fluid from patients and controls was analyzed by two-dimensional gels and the proteins were identified by matrix-assisted laser desorption ionization mass spectrometry (MS) in the MS and MS/MS mode. 54 different gene products were identified, which were mainly plasma proteins. The level of apolipoprotein A-IV was significantly decreased in the schizophrenic patients compared to that in the controls. Little is known about the function of this apolipoprotein in the central nervous system. The levels of certain other proteins, like haptoglobin, fibrinogen, complement component 3, and Gc-globulin, were altered in the disease group as well, however, the changes did not reach a statistical significance.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Recently, the nested genes G72 and G30 on chromosome 13q32-q33 have been implicated in the etiology of schizophrenia. We genotyped six single-nucleotide polymorphisms (SNPs: rs3916965, rs3916967, ...rs2391191, rs778294, rs779293 and rs3918342), which span approximately 82.5 kb in the region encompassing the G72/G30 genes in 1176 Han Chinese subjects (588 cases and 588 controls) and 365 Scottish subjects (183 cases and 182 controls). Significant association between an allele of marker rs778293 and schizophrenia was found in our Chinese samples (P = 0.0013), and was replicated in the Scottish samples (P = 0.022). LD analysis revealed that four SNPs between rs3916965 and rs778294 were in LD, called block I, and the two distal SNPs (rs778293 and rs3918342) constituted a block II in both the Chinese and Scottish samples. We selected one SNP from each block (rs778294 from block I and rs778293 from block II), and then analyzed the haplotypes. A significant difference was observed for the common haplotype GC in the Chinese sample (P = 0.0145), and was replicated in the Scottish sample (P = 0.003). On meta-analysis, we separately analyzed the studies in Asian and European populations because of significant heterogeneity in the homogeneity test. We found a statistically significant association between rs778293 and schizophrenia in Asian populations, but no difference was found between cases and controls in the European populations. Overall, our data give further support to the existing evidence that G72/G30 genes are involved in conferring susceptibility to schizophrenia.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Neurotransmitter-based hypotheses have so far led to only moderate success in predicting new pathogenetic findings in etiology of schizophrenia. On the other hand, the more recent oligodendroglia ...hypotheses of this disorder have been supported by an increasing body of evidence. For example, the expression level of the myelin associated glycopretein (
MAG) gene has been shown to be significantly lower in schizophrenia patient groups compared to control groups. Such an effect might be a result of genetic variations of the
MAG gene. In order to test this hypothesis, we genotyped four markers within the
MAG locus in 413 trios sample of the Han Chinese using allele-specific PCR. None of the four markers revealed noticeable allelic significance. However, the four-marker and two-marker haplotypes covering components rs720309 and rs720308 were observed to be significantly associated with schizophrenia (
P<0.0001) in this study. In addition, we identified one common risk haplotype TA (rs720309–rs720308, present in 78.5% of the general population) that showed increased evidence of overtransmission from parents to affected offspring (
P=0.0001). The results demonstrated
MAG might play a role in genetic susceptibility to schizophrenia. Furthermore, our finding of a possible association between the
MAG locus and schizophrenia is in agreement with the hypotheses of oligodendrltic and myelination dysfunction.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
CONTEXT Schizophrenia is a common major mental disorder. Intrauterine nutritional
deficiency may increase the risk of schizophrenia. The main evidence comes
from studies of the 1944-1945 Dutch Hunger ...Winter when a sharp and time-limited
decline in food intake occurred. The most exposed cohort conceived during
the famine showed a 2-fold increased risk of schizophrenia. OBJECTIVE To determine whether those who endured a massive 1959-1961 famine in
China experienced similar results. DESIGN, SETTING, AND PARTICIPANTS The risk of schizophrenia was examined in the Wuhu region of Anhui,
one of the most affected provinces. Rates were compared among those born before,
during, and after the famine years. Wuhu and its surrounding 6 counties are
served by a single psychiatric hospital. All psychiatric case records for
the years 1971 through 2001 were examined, and clinical and sociodemographic
information on patients with schizophrenia was extracted by researchers who
were blinded to the nature of exposure. Data on number of births and deaths
in the famine years were available, and cumulative mortality was estimated
from later demographic surveys. MAIN OUTCOME MEASURES Evidence of famine was verified, and unadjusted and mortality-adjusted
relative risks of schizophrenia were calculated. RESULTS The birth rates (per 1000) in Anhui decreased approximately 80% during
the famine years from 28.28 in 1958 and 20.97 in 1959 to 8.61 in 1960 and
11.06 in 1961. Among births that occurred during the famine years, the adjusted
risk of developing schizophrenia in later life increased significantly, from
0.84% in 1959 to 2.15% in 1960 and 1.81% in 1961. The mortality-adjusted relative
risk was 2.30 (95% confidence interval, 1.99-2.65) for those born in 1960
and 1.93 (95% confidence interval, 1.68-2.23) for those born in 1961. CONCLUSION Our findings replicate the Dutch data for a separate racial group and
show that prenatal exposure to famine increases risk of schizophrenia in later
life.
HIV-associated pulmonary arterial hypertension (PAH) is likely a more prevalent noninfectious complication of AIDS than previously recognized. Furthermore, the majority of HIV-PAH cases occur in ...individuals with a history of intravenous drug use. In this study we used a simian immunodeficiency (SIV) macaque model and a primary cell-culture system to investigate the association between drug abuse and HIV infection in HIV-PAH development.
The archival lung tissues from macaques previously used to study the effect of morphine on SIV infection-associated neuropathogenesis were analyzed for pulmonary vascular changes. The direct effect of HIV proteins and illicit drugs was investigated on oxidative stress, survival, and proliferation of human pulmonary microvascular endothelial cells.
SIVmacR71/17E-infected rhesus macaques treated with morphine (VM group) demonstrated significant pulmonary vascular remodeling, including the presence of early and advanced complex (plexiform) lesions, when compared with either the SIV-infected (V group) or morphine-treated uninfected (M group) macaques. However, both the V (two of five) and VM (two of six) groups included some animals with Pneumocystis jirovecii pneumonia. The endothelial cells lining the vessels with medial hypertrophy or initial-stage intimal lesions in lung sections from VM macaques demonstrated an increase in positivity for both terminal dUTP nick-end labeling and Ki67. Oxidative stress-mediated enhanced apoptosis followed by enhanced proliferation of endothelial cells was observed on simultaneous treatment with viral proteins and drugs of abuse compared with either treatment alone.
Our findings suggest that SIV/HIV protein(s) and morphine interact to cause the proliferation of apoptosis-resistant endothelial cells leading to angio-obliteration.
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