A smooth skeletal rearrangement took place when a chloroindolenine (2) derived from 3-oxotabersonine (1) was treated under solvolytic conditions. The structure of the rearrangement product (3) was ...clarified unambiguously by X-ray crystal analysis.
71 CHEMICAL CONVERSION OF TABERSONINE ANALOGUES Aimi, Norio; Asada, Yoshihisa; Tanabe, Sohei ...
Symposium on the Chemistry of Natural Products, symposium papers,
1979/09/20
Journal Article
Odprti dostop
A Japanese Apocynaceae plant, Amsonia elliptica Roem. et Schult, contains tabersonine (3) and the biogenetically related minor bases in the seeds. 3-Oxo-tabersonine (4), which is one of the minor ...bases and is also derivable from tabersonine through KMnO_4 oxidation, was converted to a vincamine type compound (21). The main product, however, was α-keto ester (22). In this case, a slow rearrangement of 20 to 21 allowed a further step of oxidation to take place to give 22. An attempt was made to convert an aspidosperma skeleton to that of Melodinus alkaloids along the proposed biogenetic route. 3-Oxo-tabersonine (4), in which the tertiary nitrogen of tabersonine was converted to an amide function, was used as the starting material. Under neutral conditions a rearrangement product (31) of an unnatural structural skeleton was obtained. The structure of 31 was elucidated on the chemical and spectral bases. Some anomalous properties of this product were pointed out. As a result, the initial object to obtain the framework of Melodinus alkaloids remained to be studied further.
This real-world study examined the prevalence of programmed death ligand-1 (PD-L1) expression and assessed the frequency of microsatellite instability-high (MSI-H) status and Epstein-Barr virus (EBV) ...positivity in Japanese patients with advanced gastric and gastroesophageal junction (GEJ) adenocarcinoma. This multicenter (5 sites), retrospective, observational study (November 2018-March 2019) evaluated Japanese patients with advanced gastric and GEJ adenocarcinoma after surgical resection (Stage II/III at initial diagnosis) or unresectable advanced cancer (Stage IV). The primary objectives were prevalence of PD-L1 expression (combined positive score CPS ≥1), MSI status, and EBV positivity. Tumor specimens of 389/391 patients were analyzed (male, 67.1%; mean age, 67.6 ± 12.2 years); 241/389 (62%) were PD-L1 positive, 24/379 (6.3%) had MSI-H tumors, and 13/389 (3.3%) were EBV positive. PD-L1 expression was higher in tumor-infiltrating immune cells than in tumor cells for lower CPS cutoffs. Among patients with MSI-H tumors and EBV-positive tumors, 19/24 (79.2%) and 9/13 (69.2%), respectively, were PD-L1 positive. A greater proportion of patients with MSI-H tumors (83.3% 20/24) were PD-L1 positive than those with MSI-low/stable tumors (60.8% 216/355; p = .0297); similarly, an association was observed between history of H pylori infection and PD-L1 expression. A higher proportion of patients with MSI-H tumors demonstrated PD-L1 expression with a CPS ≥10 (66.7% 16/24) vs those with MSI-low/stable tumors (24.8% 88/355; p < .0001). The prevalence of PD-L1 positivity among Japanese patients was comparable to that in previous pembrolizumab clinical trials and studies in gastric cancer. Particularly, higher PD-L1 expression was observed in MSI-H tumors.
Acute ischemic stroke (AIS) is a serious cause of mortality and disability. AIS is a serious cause of mortality and disability. Early diagnosis of atherosclerosis, which is the major cause of AIS, ...allows therapeutic intervention before the onset, leading to prevention of AIS.
Serological identification by cDNA expression cDNA libraries and the protein array method were used for the screening of antigens recognized by serum IgG antibodies in patients with atherosclerosis. Recombinant proteins or synthetic peptides derived from candidate antigens were used as antigens to compare serum IgG levels between healthy donors (HDs) and patients with atherosclerosis-related disease using the amplified luminescent proximity homogeneous assay-linked immunosorbent assay.
The first screening using the protein array method identified death-inducer obliterator 1 (DIDO1), forkhead box J2 (FOXJ2), and cleavage and polyadenylation specificity factor (CPSF2) as the target antigens of serum IgG antibodies in patients with AIS. Then, we prepared various antigens including glutathione S-transferase-fused DIDO1 protein as well as peptides of the amino acids 297-311 of DIDO1, 426-440 of FOXJ2, and 607-621 of CPSF2 to examine serum antibody levels. Compared with HDs, a significant increase in antibody levels of the DIDO1 protein and peptide in patients with AIS, transient ischemic attack (TIA), and chronic kidney disease (CKD) but not in those with acute myocardial infarction and diabetes mellitus (DM). Serum anti-FOXJ2 antibody levels were elevated in most patients with atherosclerosis-related diseases, whereas serum anti-CPSF2 antibody levels were associated with AIS, TIA, and DM. Receiver operating characteristic curves showed that serum DIDO1 antibody levels were highly associated with CKD, and correlation analysis revealed that serum anti-FOXJ2 antibody levels were associated with hypertension. A prospective case-control study on ischemic stroke verified that the serum antibody levels of the DIDO1 protein and DIDO1, FOXJ2, and CPSF2 peptides showed significantly higher odds ratios with a risk of AIS in patients with the highest quartile than in those with the lowest quartile, indicating that these antibody markers are useful as risk factors for AIS.
Serum antibody levels of DIDO1, FOXJ2, and CPSF2 are useful in predicting the onset of atherosclerosis-related AIS caused by kidney failure, hypertension, and DM, respectively.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Locally advanced pancreatic cancer (LAPC), which progresses locally and surrounds major vessels, has historically been deemed unresectable. Surgery alone failed to provide curative resection and ...improve overall survival. With the advancements in treatment, reports have shown favorable results in LAPC after undergoing successful chemotherapy therapy or chemoradiation therapy followed by surgical resection, so-called “conversion surgery”, at experienced high-volume centers. However, recognizing significant regional and institutional disparities in the management of LAPC, an international consensus meeting on conversion surgery for LAPC was held during the Joint Congress of the 26th Meeting of the International Association of Pancreatology (IAP) and the 53rd Annual Meeting of Japan Pancreas Society (JPS) in Kyoto in July 2022. During the meeting, presenters reported the current best multidisciplinary practices for LAPC, including preoperative modalities, best systemic treatment regimens and durations, procedures of conversion surgery with or without vascular resections, biomarkers, and genetic studies. It was unanimously agreed among the experts in this meeting that “cancer biology is surpassing locoregional anatomical resectability” in the era of effective multiagent treatment. The biology of pancreatic cancer has yet to be further elucidated, and we believe it is essential to improve the treatment outcomes of LAPC patients through continued efforts from each institution and more international collaboration. This article summarizes the agreement during the discussion amongst the experts in the meeting. We hope that this will serve as a foundation for future international collaboration and recommendations for future guidelines.
The diamond wheel with a diameter within several millimeters has the disadvantage that it is difficult to improve the surface roughness, because the circumferential speed of the wheel is slow and the ...number of grains on the wheel is low. To suppress the decrease in grain number, a thermoplastic resin was chosen as a bonding material. This material softens on heating and solidifies again when cooled. A method of returning the abrasive grains to the wheel with the possibility of dropout was developed using heat under grinding. In this paper, a newly developed thermoplastic resin-bonded diamond wheel and a conventional thermosetting resin-bonded diamond wheel were tested under the same conditions, and their performances were compared. The arithmetic-mean-deviation of the profile of the newly developed diamond wheel was 51% of the value of the conventional diamond wheel at the first stage of grinding. The wear volume of the new wheel was a 57% of the value of the conventional wheel.
To prevent a decrease in the number of grains from the wheel surface, a thermoplastic resin-bonded diamond wheel was developed. The heat generated while grinding can soften thermoplastic resin and ...the grains can be buried in the wheel surface by contact f
We investigated the relationship between peak expiratory flow (PEF), age and standing height in 2785 Japanese volunteers (1047 males), aged 15–84 years, who had never smoked and who satisfied other ...strict criteria of normality. Many reports of regression equations for PEF by country and ethnicity are prepared using Wright or mini-Wright PEF meters, which have been calibrated by human subjects. Yet, no study has been performed in any country to determine the reference values of PEF on the American Thoracic Society (ATS) scale, which is calibrated by a computerdriven mechanical pump.
Peak expiratory flow was measured with mini-Wright meters calibrated on the Wright scale. All subjects were taught how to perform a forced expiratory maneuver: the highest of three PEF values was recorded and standing height was measured. The Miles equation was used to convert mini-Wright PEF values (traditional scale) to values using the new ‘mechanical’ PEF, which the ATS has recommended (ATS scale). In the analysis of the data, a model based on age, age squared and age cubed was used to derive curvilinear regression equations for PEF on age and standing height for each sex.
There was adequate representation of subjects of each sex at all ages to 74 years. Curves plotted from the regression equations rose during adolescence and early adulthood, reached maximum values at 35 years in males and 40 years in females and then declined in an approximately linear manner. For both sexes, standing height fell progressively with increasing age.
From the regression equations, predicted values of PEF can be derived for any Japanese adult aged 15–74 years. We were able to obtain predicted equations for PEF in normal Japanese adults using both the Wright and ATS scales. Direct comparison of our regressions with those reported in other populations was limited by differences in methodology and analysis. In comparable studies of Chinese and Indian populations, the PEF values in those studies were appreciably lower than ours. Our regressions were remarkably similar to those reported in a study of British subjects that used virtually identical entry criteria and methods.
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