THE SPIROKETALS CONTAINING A BENZYLOXYMETHYL MOIETY AT C8 POSITION SHOWED THE MOST POTENT APOPTOSIS-INDUCING ACTIVITY

Abstract: The spiroketals containing a benzyloxymethyl moiety at the C8 position showed the most potent apoptosis-inducing activity, whereas its analogous compounds lacking any substituent at C8 or possessing ones other than the benzyloxymethyl moiety at C8 were all much less active. These results strongly suggest an important role of the benzyloxymethyl moiety linked to the C8 oxygen ato

A comparative study of the sarcopenia screening in older patients with interstitial lung disease

Background: The Asian Working Group for Sarcopenia 2019 (AWGS 2019) is the gold standard diagnostic criteria for sarcopenia in Asian populations. The calf circumference (CalF), the strength, assistance in walking, rising from a chair, climbing stairs, and falls (SARC-F) and the SARC-CalF questionnaires for sarcopenia screening have been used by AWGS 2019. The aim of this study was to assess accuracy of these three sarcopenia screening tools in patients with interstitial lung disease.Methods: In this cross-sectional study, stable patients with interstitial lung disease were enrolled. The SARC-F, SARC-CalF, and CalF, used in patients with interstitial lung disease, were compared to the diagnostic criteria proposed by AWGS 2019. The accuracy of screening tools was compared using sensitivity and specificity. Moreover, areas under the receiver operating characteristic curves (AUC) were computed.Results: Seventy eight patients were analyzed, and sarcopenia was identified in 25 (32.1%) patients with interstitial lung disease by the AWGS 2019 criteria. The sensitivity of the CalF was highest (96%) of the three screening tools, while the specificity was 60%. The sensitivity of SARC-F and SARC-CalF were 24% and 68%, while the specificity were 92% and 66%, respectively. The AUCs of CalF, SARC-F, and SARC-CalF in all patients were 0.78, 0.58, and 0.67, respectively.Conclusions: The CalF is most suitable for screening sarcopenia in patients with interstitial lung disease, while SARC-F and SARC-CalF are not

Association between hospital acquired disability and post-discharge mortality in patients after living donor liver transplantation

Background: Hospital-acquired disability (HAD) in patients who undergo living donor liver transplantation (LDLT) is expected to worsen physical functions due to inactivity during hospitalization. The aim of this study was to explore whether a decline in activities of daily living from hospital admission to discharge is associated with prognosis in LDLT patients, who once discharged from a hospital.Methods: We retrospectively examined the relationship between HAD and prognosis in 135 patients who underwent LDLT from June 2008 to June 2018, and discharged from hospital once. HAD was defined as a decline of over 5 points in the Barthel Index as an activity of daily living assessment. Additionally, LDLT patients were classified into four groups: low or high skeletal muscle index (SMI) and HAD or non-HAD. Univariate and multivariate Cox proportional hazard models were used to evaluate the association between HAD and survival.Results: HAD was identified in 47 LDLT patients (34.8%). The HAD group had a significantly higher all-cause mortality than the non-HAD group (log-rank: p < 0.001), and in the HAD/low SMI group, all-cause mortality was highest between the groups (log-rank: p < 0.001). In multivariable analysis, HAD was an independent risk factor for allcause mortality (hazard ratio [HR]: 16.54; P < 0.001) and HAD/low SMI group (HR: 16.82; P = 0.002).Conclusion: HAD was identified as an independent risk factor for all-cause mortality suggesting that it could be a key component in determining prognosis after LDLT. Future larger-scale studies are needed to consider the overall new strategy of perioperative rehabilitation, including enhancement of preoperative physiotherapy programs to improve physical function

Observation of Live Ticks (Haemaphysalis flava) by Scanning Electron Microscopy under High Vacuum Pressure

Scanning electron microscopes (SEM), which image sample surfaces by scanning with an electron beam, are widely used for steric observations of resting samples in basic and applied biology. Various conventional methods exist for SEM sample preparation. However, conventional SEM is not a good tool to observe living organisms because of the associated exposure to high vacuum pressure and electron beam radiation. Here we attempted SEM observations of live ticks. During 1.5×10−3 Pa vacuum pressure and electron beam irradiation with accelerated voltages (2–5 kV), many ticks remained alive and moved their legs. After 30-min observation, we removed the ticks from the SEM stage; they could walk actively under atmospheric pressure. When we tested 20 ticks (8 female adults and 12 nymphs), they survived for two days after SEM observation. These results indicate the resistance of ticks against SEM observation. Our second survival test showed that the electron beam, not vacuum conditions, results in tick death. Moreover, we describe the reaction of their legs to electron beam exposure. These findings open the new possibility of SEM observation of living organisms and showed the resistance of living ticks to vacuum condition in SEM. These data also indicate, for the first time, the usefulness of tick as a model system for biology under extreme condition

Minimum Information about a Biosynthetic Gene cluster

A wide variety of enzymatic pathways that produce specialized metabolites in bacteria, fungi and plants are known to be encoded in biosynthetic gene clusters. Information about these clusters, pathways and metabolites is currently dispersed throughout the literature, making it difficult to exploit. To facilitate consistent and systematic deposition and retrieval of data on biosynthetic gene clusters, we propose the Minimum Information about a Biosynthetic Gene cluster (MIBiG) data standard.Chemistry and Chemical Biolog

Stepwise cyclopropanation on the polycyclopropanated polyketide formation in jawsamycin biosynthesis

Jawsamycin is a polyketide-nucleoside hybrid with a unique poly-cyclopropane moiety on a single polyketide chain. The unexpected isolation of cyclopropane deficient jawsamycin analogs allowed us to propose a stepwise cyclopropanation mechanism for the enzymatic synthesis of this polyketide. The concise timing of the cyclopropanation could be regulated by a delicate balance between reaction rates of the condensation and cyclopropanation reactions

Hg(OTf)2-catalyzed direct vinylation of tryptamines and versatile applications for tandem reactions

We have developed a unique catalytic protocol for direct gem-vinylation of tryptamine derivatives employing Hg(OTf)2 as the optimum catalyst. The intermolecular vinylations with a series of aromatic acetylenes proceeded under ambient temperature at the C2 positions of indoles with high functional group tolerance. Based on the mechanistic insights, we further developed the tandem reactions successfully constructing a quaternary center

Biogenetically inspired synthesis and skeletal diversification of indole alkaloids

To access architecturally complex natural products, chemists usually devise a customized synthetic strategy for constructing a single target skeleton. In contrast, biosynthetic assembly lines often employ divergent intramolecular cyclizations of a polyunsaturated common intermediate to produce diverse arrays of scaffolds. With the aim of integrating such biogenetic strategies, we show the development of an artificial divergent assembly line generating unprecedented numbers of scaffold variations of terpenoid indole alkaloids. This approach not only allows practical access to multipotent intermediates, but also enables systematic diversification of skeletal, stereochemical and functional group properties without structural simplification of naturally occurring alkaloids. Three distinct modes of [412] cyclizations and two types of redox-mediated annulations provided divergent access to five skeletally distinct scaffolds involving iboga-, aspidosperma-, andranginine- and ngouniensine-type skeletons and a non-natural variant within six to nine steps from tryptamine. The efficiency of our approach was demonstrated by successful total syntheses of (+/-)-vincadifformine, (+/-)-andranginine and (2)-catharanthine

Biosynthetic study of FR-900848: unusual observation on polyketide biosynthesis that did not accept acetate as origin of acetyl-CoA

The biosynthetic pathway of a potent antifungal agent, FR-900848, has been examined by administration of several 13C-labeled precursors to Streptoverticillium fervens HP-891. Although none of the 13C-labeled acetate was incorporated into FR-900848, the labeling pattern of FR-900848 derived from d-[U-13C6]glucose revealed that the fatty acid backbone of FR-900848 has been biosynthesized via a polyketide pathway. These unusual results strongly show that the major pathway to provide acetyl-CoA in this microorganism is glycolysis. Feeding experiments with d-[U-13C6]glucose, [1,3-13C2]glycerol, and l-[Me-13C]methionine provided information on the biosynthetic origin of structurally unusual parts (polycyclopropane and aminonucleoside) in this antibiotic