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The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.
To explore whether and how group cognitive-behavioural therapy (GCBT) plus medication differs from medication alone for the treatment of generalised anxiety disorder (GAD).
Hundred and seventy patients were randomly assigned to the GCBT plus duloxetine (n=89) or duloxetine group (n=81). The primary outcomes were Hamilton Anxiety Scale (HAMA) response and remission rates. The explorative secondary measures included score reductions from baseline in the HAMA total, psychic, and somatic anxiety subscales (HAMA-PA, HAMA-SA), the Hamilton Depression Scale, the Severity Subscale of Clinical Global Impression Scale, Global Assessment of Functioning, and the 12-item Short-Form Health Survey. Assessments were conducted at baseline, 4-week, 8-week, and 3-month follow-up.
At 4 weeks, HAMA response (GCBT group 57.0% vs. control group 24.4%, p=0.000, Cohen’s d=0.90) and remission rates (GCBT group 21.5% vs. control group 6.2%, p=0.004; d=0.51), and most secondary outcomes (all p<0.05, d=0.36−0.77) showed that the combined therapy was superior. At 8 weeks, all the primary and secondary significant differences found at 4 weeks were maintained with smaller effect sizes (p<0.05, d=0.32−0.48). At 3-month follow-up, the combined therapy was only significantly superior in the HAMA total (p<0.045, d=0.43) and HAMA-PA score reductions (p<0.001, d=0.77). Logistic regression showed superiority of the combined therapy for HAMA response rates [odds ratio (OR)=2.12, 95% confidence interval (CI) 1.02−4.42, p=0.04] and remission rates (OR=2.80, 95% CI 1.27−6.16, p=0.01).
Compared with duloxetine alone, GCBT plus duloxetine showed significant treatment response for GAD over a shorter period of time, particularly for psychic anxiety symptoms, which may suggest that GCBT was effective in changing cognitive style.
Ecological evidence suggests that niacin (nicotinamide and nicotinic acid) fortification may be involved in the increased prevalence of obesity and type 2 diabetes, both of which are associated with insulin resistance and epigenetic changes. The purpose of the present study was to investigate nicotinamide-induced metabolic changes and their relationship with possible epigenetic changes. Male rats (5 weeks old) were fed with a basal diet (control group) or diets supplemented with 1 or 4 g/kg of nicotinamide for 8 weeks. Low-dose nicotinamide exposure increased weight gain, but high-dose one did not. The nicotinamide-treated rats had higher hepatic and renal levels of 8-hydroxy-2′-deoxyguanosine, a marker of DNA damage, and impaired glucose tolerance and insulin sensitivity when compared with the control rats. Nicotinamide supplementation increased the plasma levels of nicotinamide, N1-methylnicotinamide and choline and decreased the levels of betaine, which is associated with a decrease in global hepatic DNA methylation and uracil content in DNA. Nicotinamide had gene-specific effects on the methylation of CpG sites within the promoters and the expression of hepatic genes tested that are responsible for methyl transfer reactions (nicotinamide N-methyltransferase and DNA methyltransferase 1), for homocysteine metabolism (betaine–homocysteine S-methyltransferase, methionine synthase and cystathionine β-synthase) and for oxidative defence (catalase and tumour protein p53). It is concluded that nicotinamide-induced oxidative tissue injury, insulin resistance and disturbed methyl metabolism can lead to epigenetic changes. The present study suggests that long-term high nicotinamide intake (e.g. induced by niacin fortification) may be a risk factor for methylation- and insulin resistance-related metabolic abnormalities.
With the ATNF Mopra telescope we are performing a survey in the 12CO(1–0) line to map the molecular gas in the Large Magellanic Cloud. For some regions we also obtained interferometric maps of the high density gas tracers HCO+ and HCN with the Australia Telescope Compact Array. Here we discuss the properties of the elongated molecular complex that stretches about 2 kpc southward from 30 Doradus. Our data suggest that the complex, which we refer to as the ‘molecular ridge’, is not a coherent feature but consists of many smaller clumps that share the same formation history. Likely triggers of molecular-cloud formation are shocks and shearing forces that are present in the surrounding south-eastern Hi overdensity region, a region influenced by strong ram pressure and tidal forces. The molecular ridge is at the western edge of the the overdensity region where a bifurcated velocity structure transitions into a single disk velocity component. We find that the 12CO(1–0) and Hi emission peaks in the molecular ridge are typically near each other but never coincide. A likely explanation is the conversion of warmer, low-opacity Hi to colder, high-opacity Hi from which H2 subsequently forms. On smaller scales we find that very dense molecular gas, as traced by interferometric HCO+ and HCN maps, is associated with star formation along shocked filaments and with rims of expanding shell-like structures, both created by feedback from massive stars.
Two sets of reciprocal introgression lines (ILs) and a population of recombinant inbred lines (RILs) derived from the cross between japonica cultivar Xiushui09 and indica breeding line IR2061-520-6-9 (abbreviated as IR2061) were used to identify QTL for heading date (HD). Phenotyping was conducted in Hainan Island for two winter seasons (2007 and 2009). Nine QTLs were detected in the ILs with Xiushui09 background (XS-ILs), and four of which were repeatedly mapped across 2 years. Five QTLs were identified in the ILs with IR2061 background (IR-ILs), and three of which were commonly detected in 2 years. All commonly detected QTL had the same direction of gene effect. Seven QTL for HD were identified in the RILs in 2009. Only three (25%) QTLs were commonly detected using all the three populations (XS-ILs, IR-ILs and RILs). The number of commonly identified QTLs among populations was related to degree of similarity of their genetic backgrounds, suggesting that the genetic background effect is important for detecting HD QTL. QHd7 and QHd10b stably expressed in different populations and across years thus would be exploited in rice breeding programme. Moreover, lines with both of QHd7 and QHd10b resulted in at least 3 days earlier than lines with only one of them QTL, showing evident pyramiding effect.
Bombardment of silicon surfaces by low-energy nitrogen ions has been investigated as a possible process for growing films of silicon nitride at relatively low temperature(<500°C). Broad ion beams of energy 300–1200eV have been used to grow ultrathin silicon nitride films. Film thickness and chemical states are analyzed using ellipsometery, X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy(AES). As a result, thicknesses dependence on ion energy, substrate temperature and implantation time have been investigated. The thicknesses of films obtained appear to increase with ion energy in the range from 300 to 1200eV, and with time of bombardment. The thicknesses are also observed to vary slightly with substrate temperature. The growth mechanism has also been investigated and discussed. The average activation energy of nitridation rates is about 3.5meV which indicates nonthermal process kinetics, compared to an activation energy of 0.2–0.6eV for thermal nitridation. AES results show that the atomic ratio [N]/[Si] is about 1.5, larger than that of pure Si3N4. All the analyses show that silicon nitride films of about 60Å thickness have been grown on silicon by low-energy ion beam nitridation.
C50 films, are deposited on Si(111) substrates using neutral cluster beams of fullerenes generated from a crucible with a special nozzle. X-ray diffraction (XRD) have been used to investigate the structural properties of C50 films, which indicate highly textural films as close-packed structure with strong (110) XRD assignment and 400Å for correlation length. Raman spectrum indicates the existence of stable C60 films. X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) measurements are carried out to analyze the electronic properties of the films. The resistivity to contamination of C50 film deposited here is better than that deposited by MBE. Different kinds of oxygen contamination on the surfaces of C50 films and HDPG are detected by the results of O 1s XPS analyses.
Films (with thicknesses about thousands A) of a new form of carbon allotrope, CIO also known as Fullerenes, are deposited on Si(111) substrates using ionized cluster beam deposition (ICBD) technique at low (65V) accelerating voltage V. X-ray &-20 diffraction (XRD) have been used to investigate the structural properties of C6Ofi lms, indicating hexagonal close-packed structure with strong (002) XRD assignment together with weak (100), (112) and(004) assignments. Raman spectra, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) are carried out to make detailed studies of the electronic properties of the films and to illustrate differences between CO films and amorphous carbon films which are deposited by ICBD at high accelerating voltage V >400V. Cio soccer-balls are found to be broken into fragments as accelerating field overtakes about 400V, indicated by the results of XPS, Raman spectra, XRD, and UV/visible absorption spectra.
CN1 thin films have been synthesized by ion-beam-assisted laser ablation of graphite. Films with N-concentration of 45% are obtained, indicated by high energy backseattering spectrum (HEBS). Raman and X-ray photoelectron spectroscopy (XPS) data confirm the existence of carbon-nitrogen bonds. Polycrystallites beta-CjNi structure has been detected in the amorphous matrix of the films, as indicated by transmission electron microscopy (TEM) and electron diffraction. Qualitative tests indicate that the films are relatively hard and adhesive.
C60 films have been deposited using a partially ionized cluster beam deposition (PIBD) technique. The experimental results show that as Va. exceeds about 400 V almost all the C60 molecules fragmentate at collision with the substrate and the obtained films turn to be amorphous carbon layers at elevated Va, indicated by measurements of Raman spectra, X-ray diffraction, and ellipsometry.
Ionized cluster beam deposition (ICBD) technique has been used to deposit Ag films on both Si(111) and Si(100) substrates. Sizes of clusters in ionized cluster beam are found to distribute in a range of 100–600 atoms/cluster. X-ray diffraction (XRD), and α-step profile methods are used to analyze the properties of Ag films. As a comparison, Ag films deposited by conventional evaporation are also investigated. Highly textured Ag films with strong (111) orientation on Si (111) have been obtained at high accelerating voltage Va=4kV. The crystallinity and surface flatness of Ag films can be improved by ICBD at high accelerating voltages.
C60 films, which are deposited by partially ionized beam deposition (PIBD), are doped by 100 keV boron ion implantation at dose ranging from 3*1014 to 1*1016 cm2 The implantation process has been studied using Fourier transform infrared spectroscopy (FTIR), Raman spectra and X-ray diffraction (XRD) analyses. Almost all C60 soccer-balls in the doped region in the films are found to be broken at dose of 1*1016 cm2, while at dose less than 6*1014 cm2 a few C60 molecules remain undestroyed and maintain the original structural properties.
Covalent carbon nitride films have been synthesized by laser ablation and ion-beam coprocessing. Different laser ablations give different ablated graphite plasma. Beta- C3N4 polycrystalline has been found in the deposited films. Under laser energy of 50 mJ per pulse, the adoption of 532 nm laser used for ablation of graphite is proposed for the purpose of production of good carbon nitride films. The C-N crystal structures can be improved by followed ion-beam processing.
The effect of the high-energy-electron irradiation on the crystallization process in poly(vinylidene fluoride-trifluoroethyelene) [(P(VDF-TrFE)] 65/35 mol% copolymers was studied by nonisothermal crystallization using the differential scanning calorimetry (DSC) technique. The experimental data are analyzed using modified Avrami, Ozawa, and combined Avrami-Ozawa methods. It is found that the crystals grow in three dimensions in the irradiated samples. It is found that the irradiation results in a lower crystallization temperature and a lower crystallization activation energy. It is also found that the irradiated samples have a lower crystallization temperature than the unirradiated samples. All these results indicate that the crystals grown in the irradiated samples have a smaller surface energy, which corresponds to a thicker interfacial layer.
Polyimide (PI)-matrix composite films containing inorganic nanoparticles (nano-Al2O3 and nano-TiO2) have been fabricated. A proposed model is used to explain different structures of the (Al2O3–TiO2)/PI (ATP) films synthesized by employing in situ polymerization. Dependences of dielectric permittivities of the ATP films on frequency and temperature were studied. Results show the breakdown strength of the films decreases with prolonging the corona aging time. The incorporation of the nano-Al2O3 and nano-TiO2 particles significantly improves the corona resistance of the films. The corona aging also influences the infrared absorbance, the glass transition temperature (Tg), and loss factor (tanδ) of the ATP films.
The genetic diversity of dinitrogen-fixing bacteria associated with rice (Oryza sativa) was assessed by a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) approach on the nifH gene amplified directly from DNA extracted from washed rice roots and rhizospheric soil. Restriction digestion with the enzymes MnlI and HaeIII was performed to characterize 54 cloned nifH PCR products. RFLP profiles were clustered and analysed with the UPGMA program. Eight pairs of similar RFLP patterns (similarity>50%) and two pairs of homologous RFLP patterns (100% identity) were found from the washed roots and the rhizospheric soil, respectively. Three specific diazotrophic patterns were found from rhizospheric soil and rice roots. The analyses have revealed the presence of different nifH types, which appear to be significant components of the diazotrophic community in paddy fields, indicating that some of the diazotrophs may colonize the inside and the surface of the rice roots.
The construction of the sorghum (Sorghum bicolor L. Moench) molecular genetic linkage map started in the early 1990s. Molecular genetic maps with a high density of markers covering almost the entire sorghum genome have been completed and integration of a sorghum genetic and physical map is under way. The correlation between genetic linkage groups and relevant chromosomes was established and the locations of the important structures of chromosomes, such as centromeres, long and short arms, nucleolus organizer region (NOR), etc., have been identified on the linkage groups. Molecular cytogenetic mapping of each chromosome has been advanced substantially. With continuing progress in the field, sequencing of the full sorghum genome and study of sorghum functional genomics will be initiated soon.
In order to assess the influence of nutrient elements on the accumulation of β-N-oxalyl-L-α, β-diaminopropionic acid (β-ODAP; the probable cause of lathyrism) in Lathyrus sativus L. (grass pea), it was first examined under field conditions during the lifespan of a grass pea plant using high-performance liquid chromatography (HPLC). β-ODAP mainly accumulated in young seedlings, in developing and mature seeds and in young leaves, especially in young seedlings. In contrast, all mature leaves, roots, and stems showed a low level of β-ODAP. The β-ODAP accumulation pattern in seedlings grown in a nutrient-deficient solution was highest (3·57 mg/g) in shoots at 7 d growing in the nitrogen-deficient solution and higher compared to the control (2·31 mg/g) in zinc-, calcium-, phosphorus- and molybdenum-deficient shoots (P<0·05). The contents of β-ODAP in seedlings growing in other element-deficient solutions were similar to controls. When the content of β-ODAP in grass pea seedlings fertilized with different forms of organic nitrogen was assayed the results indicated that amino acids such as glutamine and serine, as well as nucleotide nitrogen, all significantly enhanced the accumulation of β-ODAP in young seedlings relative to controls (P<0·05). Taken together, these data suggest that β-ODAP accumulation in grass pea might be related to the level of total free nitrogenous compounds and that nitrogen and phosphate may be the crucial nutrient factors influencing β-ODAP content under field conditions. Thus, the application of appropriate nitrogen and phosphorus fertilizers to the soil could decrease the content of β-ODAP in the seeds and leaves of grass pea.
GbRac1 gene was cloned from Gossypium barbadense with degenerate primers and 3′-RACE. Northern blot analysis indicated that GbRac1 mRNA was expressed abundantly in G. barbadense seedlings inoculated with Verticillium dehliae compared with mock-inoculated plants. A plant constitutive expression vector pRac harbouring GbRac1 gene was constructed and leaf discs of tobacco (Nicotiana tabacum L. cv. NC89) were transformed with pRac by Agrobacterium-mediated transformation. Disease challenge test of detached leaves of the transgenic plants by inoculation with Alternaria alternata showed that resistance was enhanced dramatically compared with the non-transgenic plants. Results suggest that GbRac1 gene might have potential application in the genetic engineering of plants with enhanced disease resistance.
A 1009 bp promoter sequence of cab gene, which encodes chlorophyll a/b binding protein belonging to a class of light-inducible proteins, was cloned from Gossypium arboreum. Sequence analysis showed that it had no obvious homology with previously published cab promoters. The full-length Gacab promoter and 5′ deletions with length of 197, 504 and 779 bp were fused with gus (uid A) gene, respectively, and plant expression vectors were used for transformation of Nicotiana tabacum cv. NC89. β-Glucuronidase (GUS) histochemical assay of transgenic tobacco plants showed that GUS was expressed specifically in leaves and young green tissues. GUS was not detected in the leaves of transgenic plants grown in the dark for 6 days. However, it was highly expressed in the leaves of these plants after induction with light for another 6 days, demonstrating that the full-length Gacab promoter is a light-inducible promoter. Transient GUS expression in rice calli indicated that the expression level of Gacab504::gus was the highest and stronger than that of the CaMV 35S promoter, while expression was reduced for Gacab197::gus, Gacab779::gus and Gacab1009::gus constructs. This suggests that −197 bp to −1 bp is a basic promoter of Gacab, some positive regulatory elements may exist in −504 bp to −197 bp, and the fragment −1009 bp to −504 bp may contain negative elements.
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