Amphidinol 3 (AM3) is a marine natural product produced by the dinoflagellate Amphidinium klebsii. Although the absolute configuration of AM3 was determined in 1999 by extensive NMR analysis and degradation of the natural product, it was a daunting task because of the presence of numerous stereogenic centers on the acyclic carbon chain and the limited availability from natural sources. Thereafter, revisions of the absolute configurations at C2 and C51 were reported in 2008 and 2013, respectively.
View Article and Find Full Text PDFFor the complete structure elucidation of an endogenous sperm-activating and -attracting factor isolated from eggs of the ascidian Ascidia sydneiensis ( Assydn-SAAF), its two possible diastereomers with respect to C-25 were synthesized. Starting from ergosterol, the characteristic steroid backbone was constructed by using an intramolecular pinacol coupling reaction and stereoselective reduction of a hydroxy ketone as key steps, and the side chain was introduced by Julia-Kocienski olefination. Comparison of the NMR data of the two diastereomers with those of the natural product led to the elucidation of the absolute configuration as 25 S; thus the complete structure was determined and the first synthesis of Assydn-SAAF was achieved.
View Article and Find Full Text PDFA microbioreactor immobilized with a synthase-type mutant enzyme, Endo-M-N175Q (glycosynthase) of endo-β-N-acetylglucosaminidase derived from Mucor hiemalis (Endo-M), was constructed and used for glycoconjugate synthesis. The transglycosylation was performed with a reaction mixture containing an oxazoline derivative of sialo complex-type glycoside (SG), which was prepared from a sialo complex-type glycopeptide SGP derived from hen egg yolk, as a glycosyl donor and N-Fmoc-N-acetylglucosaminyl-l-asparagine [Fmoc-Asn(GlcNAc)-OH] as an acceptor. The reaction mixture was injected into a glycosynthase microbioreactor at a constant flow rate.
View Article and Find Full Text PDFHippo signaling is modulated in response to cell density, external mechanical forces, and rigidity of the extracellular matrix (ECM). The Mps one binder kinase activator (MOB) adaptor proteins are core components of Hippo signaling and influence Yes-associated protein 1 (YAP1) and transcriptional co-activator with PDZ-binding motif (TAZ), which are potent transcriptional regulators. YAP1/TAZ are key contributors to cartilage and bone development but the molecular mechanisms by which the Hippo pathway controls chondrogenesis are largely unknown.
View Article and Find Full Text PDFPurpose: To clarify the concordance rate of the location of uptake on positron emission tomography/computed tomography (PET/CT) and the impingement point demonstrated in computer simulation in femoroacetabular impingement (FAI) syndrome with cam morphology.
Methods: We included hip joints with FAI syndrome that underwent F-fluoride PET/CT. We also excluded hips with SUV <6.
Objectives: The aim of this study was to explore the potential of boosted tree (BT) to develop a correlation model between active pharmaceutical ingredient (API) characteristics and a tensile strength (TS) of tablets as critical quality attributes.
Methods: First, we evaluated 81 kinds of API characteristics, such as particle size distribution, bulk density, tapped density, Hausner ratio, moisture content, elastic recovery, molecular weight, and partition coefficient. Next, we prepared tablets containing 50% API, 49% microcrystalline cellulose, and 1% magnesium stearate using direct compression at 6, 8, and 10 kN, and measured TS.
The present study aimed to assess the molecular bases of cortical compensatory mechanisms following spinal cord injury in primates. To accomplish this, comprehensive changes in gene expression were investigated in the bilateral primary motor cortex (M1), dorsal premotor cortex (PMd), and ventral premotor cortex (PMv) after a unilateral lesion of the lateral corticospinal tract (l-CST). At 2 weeks after the lesion, a large number of genes exhibited altered expression levels in the contralesional M1, which is directly linked to the lesioned l-CST.
View Article and Find Full Text PDFA unified total synthesis of stemoamide-type alkaloids is reported. Our synthetic approach features the chemoselective convergent assembly of five-membered building blocks via stemoamide as the common precursor to tetracyclic natural products. The synthesis consists of two successive coupling reactions of the three five-membered building blocks.
View Article and Find Full Text PDFJ Clin Transl Endocrinol
March 2017
Aims: In recent years, aberrant DNA methylation of specific CpG sites has been detected in many types of malignant tumors, and the epigenetic regulation of promoter CpG sites is considered an important mechanism underlying carcinogenesis. This study aimed to establish the epigenetics of the malignant transformation of malignant pheochromocytoma (PCC) and paraganglioma (PGL) by performing a methylation analysis.
Materials And Methods: Based on the results of the Infinium HumanMethylation450 BeadChip array using DNA samples of PCC/PGL patients, candidate CpG sites that were hyper/hypo-methylated in metastatic tumors relative to those in the primary tumors of 2 patients with malignant PCC/PGL were selected.
Emerg Infect Dis
October 2017
We evaluated isolates obtained from children with Mycoplasma pneumoniae infection throughout Japan during 2008-2015. The highest prevalence of macrolide-resistant M. pneumoniae was 81.
View Article and Find Full Text PDFEstrogens play undisputedly important physiological roles, but lifetime exposure to estrogens has also been linked to the development of breast cancer. Moreover, imbalanced estrogen levels have been associated with various symptoms such as osteoporosis and menopausal disorders. For the improvement of such estrogen imbalances, estrogenic reagents with regulatory properties have shown promising potential.
View Article and Find Full Text PDFIn this study, we evaluated the correlation between the response surfaces for the tablet characteristics of placebo and active pharmaceutical ingredient (API)-containing tablets. The quantities of lactose, cornstarch, and microcrystalline cellulose were chosen as the formulation factors. Ten tablet formulations were prepared.
View Article and Find Full Text PDFStructure-activity relationship studies of maitotoxin (MTX), a marine natural product produced by an epiphytic dinoflagellate, were conducted using chemically synthesized model compounds corresponding to the partial structures of MTX. Both enantiomers of the LMNO ring system were synthesized via aldol reaction of the LM ring aldehyde and the NO ring ketone. These fragments were derived from a common cis-fused pyranopyran intermediate prepared through a sequence involving Nozaki-Hiyama-Kishi reaction, intramolecular oxa-Michael addition, and Pummerer rearrangement.
View Article and Find Full Text PDFSchwannoma is a benign peripheral nerve sheath tumor originating from Schwann cells. Most intracranial schwannomas arise from vestibular nerve and schwannoma in the suprasellar region is extremely rare. A 64-year-old man presented with walking disturbance and blurred vision for three months.
View Article and Find Full Text PDFChlorophyll-a specific light volume scattering functions (VSFs) by cultured phytoplankton in visible spectrum range is presented. Chlorophyll-a specific VSFs were determined based on the linear least squares method using a measured VSFs with different chlorophyll-a concentrations. We found obvious variability of it in terms of spectral and angular shapes of VSF between cultures.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
July 2017
In the title compound, CHClNO, the five-membered dioxolane ring adopts an envelope conformation with the C atom bonded to the butenoate side chain as the flap. It deviates from the mean plane of the other atoms in the ring by 0.446 (6) Å.
View Article and Find Full Text PDFBackground: Ovarian clear cell carcinoma (OCCC) is mostly resistant to standard chemotherapy that results in poor patient survival. To understand the genetic background of these tumours, we performed whole-genome sequencing of OCCC tumours.
Methods: Tumour tissue samples and matched blood samples were obtained from 55 Japanese women diagnosed with OCCC.
Sleep, fish consumption, and depression have a close relationship; however, the role of sex differences in sleep, fish consumption, and depression research is not yet well-established. This study aimed to examine whether the impact of bedtime, sleep-onset latency, sleep duration, sleep quality, and fish consumption on depressive symptoms differed in women and men. An online survey was conducted in South Korea with a stratified random sample of 600 participants between the ages of 20 and 69, whose gender and age were proportional to estimates of Korea's general population.
View Article and Find Full Text PDFIon beam irradiation-induced nanoporous structure formation was investigated on GaSb, InSb, and Ge surfaces via controlled point defect creation using a focused ion beam (FIB). This paper compares the nanoporous structure formation under the same extent of point defect creation while changing the accelerating voltage and ion dose. Although the same number of point defects were created in each case, different structures were formed on the different surfaces.
View Article and Find Full Text PDFSolitary pulmonary caseating granulomas (SPCGs) are a characteristic type of tuberculomas associated with infection with non-tuberculous mycobacteria (NTM) and other microbes; however, their significance remains unclear. The aim of the present study was to describe the clinical characteristics of patients with SPCGs in terms of diagnosis, presence of lung cancer and treatment status. A retrospective analysis of 17 immunocompetent patients with histopathologically confirmed caseating granulomas after undergoing video-assisted thoracoscopic surgery (VATS) was conducted at our center between 2011 and 2015.
View Article and Find Full Text PDFCell cycle control is a promising target in cancer treatments, and some small-molecule cyclin-dependent kinase (CDK) inhibitors have exhibited clinical effectiveness. However, no biomarkers predictive of efficacy have been developed. Recent studies have revealed that CDK inhibitor (CKI) proteins, such as p27 and p16, also induced cytoprotective autophagy in cancer cells.
View Article and Find Full Text PDFBackground: Bevacizumab, which targets vascular endothelial growth factor (VEGF)-A, has recently been proven to be effective for the treatment of epithelial ovarian cancer (EOC). Thus, interest in VEGF-A has increased. There are few reports on concomitant detection of both ligands and its soluble receptors in serum samples, and the significance of serum VEGF-A in EOC is unclear, unlike the situation with tissue samples.
View Article and Find Full Text PDFThe prevalence of Panton-Valentine leukocidin gene (pvl)-positive community-acquired methicillin-resistant Staphylococcus aureus USA300 clone, which is designated as the ST8-staphylococcal cassette chromosome (SCC) mec type IV (ST8-IV) lineage, is a major public health concern worldwide. Thus, to elucidate the prevalence and characteristics of pvl-positive community-onset MRSA in Japan, we conducted a molecular epidemiological analysis for 854 S. aureus isolates obtained from outpatients with skin infections during 2013 and 2014.
View Article and Find Full Text PDF