379 research outputs found
HYDROGEN-BOND-ASSISTED STEREOCONTROL
Radical polymerization of N,N-dimethylacrylamide (DMAAm) was investigated in the presence of tartrates, such as diethyl L-tartrate, diisopropyl L-tartrate, and di-n-butyl L-tartrate, in toluene at low temperatures. Syndiotactic polymers were obtained in the presence of tartrates, whereas isotactic polymers were obtained in the absence of tartrates. The syndiotactic-specificity increased with increasing amount of tartrates and with decreasing polymerization temperature. NMR analysis suggested that DMAAm and tartrates formed a 1:1 complex through double hydrogen bonding. A mechanism for the syndiotactic-specific radical polymerization of DMAAm is proposed
Novel CLCN7 mutations in IARO
Osteopetrosis is a heritable disorder of the skeleton that is characterized by increased bone density on radiographs caused by defects in osteoclast formation and function. Mutations in >10 genes are identified as causative for this clinically and genetically heterogeneous disease in humans. We report two novel missense variations in a compound heterozygous state in the CLCN7 gene, detected through targeted exome sequencing, in a 15-year-old Japanese female with intermediate autosomal recessive osteopetrosis
Concurrent Connection of Embryonic Chick Heart Using a Microfluidic Device for Organ-Explant-Chip
AbstractWe propose a concurrent microvascular connection method called suction-induced vascular fixation (SVF) method for the achievement of Organ-Explant-Chip which is a biologically-designed simulator having biological materials such as cells, tissues, and organs. The advantages of proposed method with using a microfluidic device are as follows: (1) operation of flexible objects (blood vessels), (2) alignment the blood vessels concurrently, and (3) reduction of the DOFs of the blood vessels. From the experimental results, we confirmed that four cardiovascular of the explanted embryonic chick heart can be induced into the fabricated microfluidic device concurrently. We have also succeeded in construction of hybrid circulatory system between artifacts and embryonic chick heart, and monitoring the response of the heart of chick embryo by supplying the culture medium
Genome-wide prediction and characterization of interactions between transcription factors in Saccharomyces cerevisiae
Combinatorial regulation by transcription factor complexes is an important feature of eukaryotic gene regulation. Here, we propose a new method for identification of interactions between transcription factors (TFs) that relies on the relationship of their binding sites, and we test it using Saccharomyces cerevisiae as a model system. The algorithm predicts interacting TF pairs based on the co-occurrence of their binding motifs and the distance between the motifs in promoter sequences. This allows investigation of interactions between TFs without known binding motifs or expression data. With this approach, 300 significant interactions involving 77 TFs were identified. These included more than 70% of the known protein–protein interactions. Approximately half of the detected interacting motif pairs showed strong preferences for particular distances and orientations in the promoter sequences. These one dimensional features may reflect constraints on allowable spatial arrangements for protein–protein interactions. Evidence for biological relevance of the observed characteristic distances is provided by the finding that target genes with the same characteristic distances show significantly higher co-expression than those without preferred distances. Furthermore, the observed interactions were dynamic: most of the TF pairs were not constitutively active, but rather showed variable activity depending on the physiological condition of the cells. Interestingly, some TF pairs active in multiple conditions showed preferences for different distances and orientations depending on the condition. Our prediction and characterization of TF interactions may help to understand the transcriptional regulatory networks in eukaryotic systems
Novel COL11A1 mutation in familial Stickler syndrome
Stickler syndrome (STL) is an autosomal, dominantly inherited, clinically variable and genetically heterogeneous connective tissue disorder characterized by ocular, auditory, orofacial and skeletal abnormalities. We conducted targeted resequencing using a next-generation sequencer for molecular diagnosis of a 2-year-old girl who was clinically suspected of having STL with Pierre Robin sequence. We detected a novel heterozygous missense mutation, NM_001854.3:n.4838G>A [NM_001854.3 (COL11A1_v001):c.4520G>A], in COL11A1, resulting in a Gly to Asp substitution at position 1507 [NM_001854.3(COL11A1_i001)] within one of the collagen-like domains of the triple helical region. The same mutation was detected in her 4-year-old brother with cleft palate and high-frequency sensorineural hearing loss
Clinical Efficacy of Capecitabine and Cyclophosphamide (XC) in Patients with Metastatic Breast Cancer
Combined low-dose therapy of oral capecitabine (Xeloda) and cyclophosphamide (XC) has been demonstrated to be useful for long-term control of lesions in patients with metastatic breast cancer (MBC) and is aimed at symptomatic alleviation and prolongation of survival. Here, a retrospective review was conducted of MBC patients administered XC at the Okayama University Hospital (OUH), to evaluate responses to XC, adverse events and time to progression (TTP). Twenty patients with MBC received XC between 2006 and 2009. With the exception of 2 elderly patients who were over the age of 70 at the initial examination, all of the patients had received prior treatment with an anthracycline and/or a taxane. No complete response (CR) cases were observed, but partial response (PR) was achieved in 6 patients (30%) and SD in 9 (45%), of whom 5 (20%) sustained SD status for >12 months. The median TTP was 6 months (range:3-27 mo.). Three patients developed Grade 3 adverse events (diarrhea, nausea and stomatitis), but no other patients developed adverse reactions causing interruption of the therapy. XC was safe even in previously treated and elderly MBC patients;moreover, it yielded remarkable clinical responses
Deep intronic GPR143 mutation in a Japanese family with ocular albinism
Deep intronic mutations are often ignored as possible causes of human disease. Using whole-exome sequencing, we analysed genomic DNAs of a Japanese family with two male siblings affected by ocular albinism and congenital nystagmus. Although mutations or copy number alterations of coding regions were not identified in candidate genes, the novel intronic mutation c.659-131 T > G within GPR143 intron 5 was identified as hemizygous in affected siblings and as heterozygous in the unaffected mother. This mutation was predicted to create a cryptic splice donor site within intron 5 and activate a cryptic acceptor site at 41nt upstream, causing the insertion into the coding sequence of an out-of-frame 41-bp pseudoexon with a premature stop codon in the aberrant transcript, which was confirmed by minigene experiments. This result expands the mutational spectrum of GPR143 and suggests the utility of next-generation sequencing integrated with in silico and experimental analyses for improving the molecular diagnosis of this disease
- …