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31.
Improving quality of life has been recognized as an important outcome for schizophrenia treatment, although the fundamental determinants are not well understood. In this study, we investigated the association between brain structural abnormalities and objective quality of life in schizophrenia patients. Thirty-three schizophrenia patients and 42 age-, sex-, and education-matched healthy participants underwent magnetic resonance imaging. The Quality of Life Scale was used to measure objective quality of life in schizophrenia patients. Voxel-based morphometry was performed to identify regional brain alterations that correlate with Quality of Life Scale score in the patient group. Schizophrenia patients showed gray matter reductions in the frontal, temporal, limbic, and subcortical regions. We then performed voxel-based multiple regression analysis in these regions to identify any correlations between regional gray matter volume and Quality of Life Scale scores. We found that among four subcategories of the scale, the Instrumental Role category score correlated with gray matter volume in the right anterior insula in schizophrenia patients. In addition, this correlation was shown to be mediated by negative symptoms. Our findings suggest that the neural basis of objective quality of life might differ topographically from that of subjective QOL in schizophrenia.  相似文献   
32.
We examined the effects of various adenine analogues on the growth and differentiation of human myeloid leukemia HL-60 cells. Some of these analogues inhibit growth and induce nitroblue tetrazolium reducing activity in HL-60 cells. Cytokinins such as kinetin, isopentenyladenine, and benzyladenine were very effective in inducing nitroblue tetrazolium reduction and morphological changes in the cells into mature granulocytes. On the other hand, cytokinin ribosides such as kinetin riboside, isopentenyladenosine, and benzylaminopurine riboside were the most potent for growth inhibition and apoptosis. Cytokinin ribosides greatly reduced the intracellular ATP content and disturbed the mitochondrial membrane potential and the accumulation of reactive oxygen species, whereas cytokinins did not. When the cells were incubated with cytokinin ribosides in the presence of O(2)(-) scavenger, antioxidant or caspase inhibitor, apoptosis was significantly reduced and differentiation was greatly enhanced. These results suggest that both cytokinins and cytokinin ribosides can induce granulocytic differentiation of HL-60 cells, but cytokinin ribosides also induce apoptosis prior to the differentiation process.  相似文献   
33.
A plant hormone, ethylene, is formed through 1-aminocyclopropane-1-carboxylic acid (ACC). A fungus, Penicillium citrinum, was found to synthesize ACC and to degrade ACC into 2-oxobutyrate and ammonia. ACC synthase, responsible for ACC synthesis in P. citrinum, was characterized on the molecular level by sequencing of N terminal and proteolytic peptides of the enzyme, and cloning and sequencing of its cDNA. The ACC synthase from P. citrinum had 430 amino acid residues and a shorter C terminal than the plant enzyme. The enzyme purified from Escherichia coli transformed with ACC-synthase-encoding DNA showed similar properties to those of the purified enzyme from P. citrinum. Saccharomyces cerevisiae with ACC synthase accumulated ACC in the medium with increasing time of incubation. The sequence of ACC synthase from P. citrinum was compared with that of the plant enzyme with discussion about important residues for catalysis.  相似文献   
34.
The objectives of this study were to investigate the fate of microorganisms by using cultivation methods as well as DNA analyses in a commercial microbiological additive (MA) in the course of the composting. Almost all the predominant species in the microbial succession during composting process determined by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) were in disagreement with those determined by the clone library method. None of the microbial species in the composting stages corresponded to the microorganisms identified in the MA either by the cultivation method or DNA analysis. The results in regard to predominant microorganisms of the MA detected from the liquid medium by the PCR-DGGE did not correspond with those detected from the MA itself and composting processes. Although no evidence was found that predominant species in the MA itself dominate in the composting process, predominant species diversity in the MA itself was markedly changed after culturing at different thermophilic temperatures. These results suggested that cultivable microorganisms in the MA did not become predominant in the composting process: however, some microorganisms that are detected from the MA itself by the DNA analysis may act effectively in the composting process.  相似文献   
35.
GGGGCC (G4C2) repeat expansion in the C9orf72 gene has been shown to cause frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Dipeptide repeat proteins produced through repeat-associated non-AUG (RAN) translation are recognized as potential drivers for neurodegeneration. Therefore, selective inhibition of RAN translation could be a therapeutic avenue to treat these neurodegenerative diseases. It was previously known that the porphyrin TMPyP4 binds to G4C2 repeat RNA. However, the consequences of this interaction have not been well characterized. Here, we confirmed that TMPyP4 inhibits C9orf72 G4C2 repeat translation in cellular and in in vitro translation systems. An artificial insertion of an AUG codon failed to cancel the translation inhibition, suggesting that TMPyP4 acts downstream of non-AUG translation initiation. Polysome profiling assays also revealed polysome retention on G4C2 repeat RNA, along with inhibition of translation, indicating that elongating ribosomes stall on G4C2 repeat RNA. Urea-resistant interaction between G4C2 repeat RNA and TMPyP4 likely contributes to this ribosome stalling and thus to selective inhibition of RAN translation. Taken together, our data reveal a novel mode of action of TMPyP4 as an inhibitor of G4C2 repeat translation elongation.  相似文献   
36.
In mammalian cells Cdk2 activity during the G(1)-S transition is mainly controlled by p27(KIP1). Although the amount and subcellular localization of p27 influence Cdk2 activity, how Cdk2 activity is regulated during this phase transition still remains virtually unknown. Here we report an entirely new mechanism for this regulation. Cdc6 the AAA+ ATPase, known to assemble prereplicative complexes on chromosomal replication origins and activate p21(CIP1)-bound Cdk2, also activated p27-bound Cdk2 in its ATPase and cyclin binding motif-dependent manner but only after the p27 bound to the Cdk2 was phosphorylated at the C terminus. ROCK, which mediates a signal for cell anchorage to the extracellular matrix and activates the mTORC1 cascade as well as controls cytoskeleton assembly, was partly responsible for C-terminal phosphorylation of the p27. In vitro reconstitution demonstrated ROCK (Rho-associated kinase)-mediated phosphorylation of Cdk2-bound p27 at the C terminus and subsequent activation of the Cdk2 by Cdc6.  相似文献   
37.
To elucidate the genetic influence of low-dose ionizing radiation at the chromosome level, we exposed human lymphoblastoid TK6-20C cells to 10 cGy of X rays. The TK mutation frequency was 5.7 +/- 1.3 x 10(-6) at the background level and 6.9 +/- 2.8 x 10(-6) after X irradiation. Although this small increase was not statistically significant (P = 0.40), we applied multilocus analysis using 4 TK locus markers and 12 microsatellite loci spanning chromosome 17 for TK mutants exhibiting loss of heterozygosity (LOH). The analysis demonstrated a clear effect of low-dose ionizing radiation. We observed radiation-specific patterns in the extent of hemizygous LOH in 14 TK mutants among the 92 mutants analyzed. The deleted regions in these patterns were larger than they were in the control mutants, where those restricted to the TK locus. Surprisingly, the radiation-specific LOH patterns were not observed among the 110 nonirradiated TK mutants in this study. They were identified previously in TK6 cells exposed to 2 Gy of X rays. We consider these hemizygous LOH mutants to be a result of end-joining repair of X-ray-induced DNA double-strand breaks.  相似文献   
38.
39.

Key message

The first Good Manufacturing Practices production of a purification-free rice-based oral cholera vaccine (MucoRice-CTB) from transgenic plants in a closed cultivation system yielded a product meeting regulatory requirements.

Abstract

Despite our knowledge of their advantages, plant-based vaccines remain unavailable for human use in both developing and industrialized countries. A leading, practical obstacle to their widespread use is producing plant-based vaccines that meet governmental regulatory requirements. Here, we report the first production according to current Good Manufacturing Practices of a rice-based vaccine, the cholera vaccine MucoRice-CTB, at an academic institution. To this end, we established specifications and methods for the master seed bank (MSB) of MucoRice-CTB, which was previously generated as a selection-marker-free line, evaluated its propagation, and given that the stored seeds must be renewed periodically. The production of MucoRice-CTB incorporated a closed hydroponic system for cultivating the transgenic plants, to minimize variations in expression and quality during vaccine manufacture. This type of molecular farming factory can be operated year-round, generating three harvests annually, and is cost- and production-effective. Rice was polished to a ratio of 95 % and then powdered to produce the MucoRice-CTB drug substance, and the identity, potency, and safety of the MucoRice-CTB product met pre-established release requirements. The formulation of MucoRice-CTB made by fine-powdering of drug substance and packaged in an aluminum pouch is being evaluated in a physician-initiated phase I study.
  相似文献   
40.
Abstract: We describe here two types of apoptotic cell death observed in the rat CNS-derived neuroblastoma B50 and B104 cells. One type was induced by dibutyryl cyclic AMP (DBcAMP) after differentiation, and the other was induced by treatment of proliferating cells with cycloheximide. When B50 and B104 cells were treated with 1 m M DBcAMP in the presence of 0.5% fetal calf serum, they began to extend neurites within 12 h and differentiated into neurons at 24 h, as reported previously. However, further cultivation with DBcAMP for up to 72 h led to flotation and, finally, death. Death was by apoptosis as shown by chromatin condensation and DNA fragmentation. Addition of a protein kinase A inhibitor or removal of DBcAMP after differentiation suppressed apoptosis, indicating the involvement of cyclic AMP and protein kinase A in apoptotic cell death. Cell death was also induced in proliferating cells without neurite outgrowth by treatment with cycloheximide. The death was also judged to be by apoptosis based on chromatin condensation and apoptotic body formation, although DNA fragmentation into small sizes was not detected. Both types of cell death showed similar responses to inhibitors for protein kinases and protein phosphatases.  相似文献   
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