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Polyene cyclizations generate molecular complexity from a linear polyene in a single step. While methods to initiate these cyclizations have been continuously expanded and improved over the years, the majority of polyene substrates are still limited to simple alkyl-substituted alkenes. In this study, we took advantage of the unique reactivity of higher-functionalized bifunctional alkenes. The realization of a polyene tetracyclization of a dual nucleophilic aryl enol ether involving a transannular endo-termination step enabled the total synthesis of the tricyclic diterpenoid pimara-15-en-3α-8α-diol. The highly flexible and modular route allowed for the preparation of a diverse library of cyclization precursors specifically designed for the total synthesis of the tetracyclic nor-diterpenoid norflickinflimiod C. The tetracyclization of three diversely substituted allenes enabled access to complex pentacyclic products and provided a detailed insight into the underlying reaction pathways.An interesting protocol for stereoselective synthesis of (-)-cytoxazone and its unnatural stereoisomer (+)-5-epi-cytoxazone from d-4-hydroxyphenylglycine in overall yields of 10% and 16%, respectively, is described. The stereoselective addition of cyanide to an N-Boc protected aminoaldehyde (tert-butyl ((R)-1-(4-methoxyphenyl)-2-oxoethyl)carbamate) (5) constitutes the key step in this approach, producing a mixture of cyanohydrins 6a and b (1,2-anti and 1,2-syn tert-butyl (2-cyano-2-hydroxy-1-(4-methoxyphenyl)ethyl)carbamate) in 89% yield, with reasonable stereoselectivity (1.01.8) in favor of the anti-Felkin product (1,2-syn). A one-pot sequence of three successive steps from this mixture produced the oxazolidinone isomers 9a and b ((4R,5R)- and (4R,5S)-4-(4-methoxyphenyl)-2-oxooxazolidine-5-carboxylate). Chromatographic column separation and reduction of the ester function of both precursors led to (-)-cytoxazone and (+)-5-epi-cytoxazone.<br /><br /> The purpose of this study was to assess the associations between the self-reported oral health-related quality of life (OHRQoL) of older Chinese people and their socio-economic status and oral health using data collected in the 4th National Oral Health Survey.<br /><br /> After multistage stratified cluster sampling, 4332 adults aged 65-74years participated in the study. After a clinical examination, the participants completed a structured questionnaire. A Mandarin version of the General Oral Health Assessment Index (GOHAI) was included in the questionnaire. Clinical examinations were carried out using the criteria recommended by the World Health Organization. Multivariate analysis was used to evaluate the associations of the clinical and socio-demographic variables with the GOHAI scores of the participants.<br /><br /> The weighted mean (SE) GOHAI score was 51.6 (0.0). Female sex and having more than 10 missing teeth, unrestored tooth spaces, more than 10 decayed teeth and a periodontal pocket ≥6mm were negatively associated with the GOHAI score, while having a higher education level and living in the Eastern region of China were positively associated with the GOHAI score.<br /><br /> After adjustment for confounders, the OHRQoL of older Chinese individuals was mainly affected by untreated dental caries and the loss of teeth. Older Chinese individuals who were male, had a higher education level, were from the Eastern region, had no unrestored tooth spaces or deep periodontal pockets and had fewer decayed or missing teeth had higher GOHAI scores, indicating better OHRQoL.<br /><br />After adjustment for confounders, the OHRQoL of older Chinese individuals was mainly affected by untreated dental caries and the loss of teeth. Older Chinese individuals who were male, had a higher education level, were from the Eastern region, had no unrestored tooth spaces or deep periodontal pockets and had fewer decayed or missing teeth had higher GOHAI scores, indicating better OHRQoL.<br /><br /> The United States (US) leads all high-income countries in gunshot wound (GSW) deaths. However, previous US studies have not evaluated the national blood transfusion utilization patterns in hospitalized GSW patients.<br /><br /> Data from 2016 to 2017 were analyzed from the Nationwide Emergency Department Sample (NEDS) and Nationwide Inpatient Sample (NIS), the largest all-payer emergency department (ED) and inpatient databases, respectively. Using stratified probability sampling, weights were applied to generate nationally representative estimates. Multivariable Poisson-regression models were used to estimate prevalence ratios (PR) of blood transfusion.<br /><br /> There were 168,315 ED visits and 58,815 hospitalizations (age=18-90 years) following a GSW. The majority of hospitalizations were men (88.5%), age 18-24 years (31.8%), and assault-related GSW (51.3%). Blacks had the largest proportion (48.7%) overall of all GSW hospitalizations; Whites accounted for the highest proportion of intentional self-harm injuries (72.4%). Blood transfusions occurred in 12.7% of hospitalizations (12.0% red blood cell [RBC], 4.9% plasma, and 2.5% platelet transfusions). Only 1.9% of cases were associated with transfusion of all three blood components. Hospitalizations with major/extreme severity of illness had significantly higher prevalence of transfusion versus those with mild/moderate severity [crude PR=4.79 (95%CI4.15-5.33, p&lt; .001)]. Overall, 8.2% of hospitalizations with GSW died, of whom 26.8% required blood transfusions, which was significantly higher than survivors [crude PR=2.34 (95%CI2.10-2.61, p&lt; .001)]. The vast majority (95%) of the transfusions among those who died were within 48 h since admission.<br /><br /> Gun-related violence is a public health emergency in the US, and GSWs are a source of significant mortality, blood utilization, and health care costs.<br /><br />Gun-related violence is a public health emergency in the US, and GSWs are a source of significant mortality, blood utilization, and health care costs.<br /><br /> In flap transfer with perforator to perforator anastomosis (FTPPA), encountering poor pulsation and blood flow in a recipient perforator intraoperatively often makes FTPPA impossible. This study sought to identify color and spectral Doppler ultrasonography (CSDUS) parameters that can aid reliable preoperative selection of a recipient perforator artery.<br /><br /> The study enrolled 38 patients with lower extremity lymphedema who underwent vascularized lymphatic tissue transfer with perforator to perforator anastomosis for physiological lymphatic flow reconstruction. In all cases, three candidate recipient perforators were searched in each lower extremities, and vessel diameter and peak systolic flow velocity (PSFV) were measured. The inclusion criteria for candidates were a vessel diameter of &gt;0.5 mm and a PSFV of &gt;10cm/s. [https://www.selleckchem.com/products/cpi-1205.html CPI-1205 cost] These measures were compared with intraoperative findings, diameters and if there was pulsation and visible spurting evident.<br /><br /> A total of 114 candidates were selected, and 52 of the candidates were dissected until suitable perforators were found.