This study analyzes single factors that affect the prognosis of severe acute respiratory syndrome (SARS) and establishes a prognosis model by multivariate analysis. We retrospectively analyzed the clinical features of SARS in 165 clinically confirmed severe cases. Both age and existence of other diseases before SARS were significantly correlated with prognosis (r=0.506 and r=0.457, respectively; P<.001). During the acute phase of SARS, lactate dehydrogenase level, degree of hypoxemia, respiratory rate, alpha -hydroxybutyric dehydrogenase level, creatine kinase isoenzyme-MB, platelet count, and number of involved lobes noted on chest radiographs, and so on, correlated markedly with the prognosis (r=0.257-0.788; P<.05). The multivariate prognosis regression model was associated with degree of hypoxemia and platelet count. The model was defined by the formula Py=1=es/(1+es), where S is [2.490 x degree of hypoxemia]-[0.050 x number of platelets], and it had a high sensitivity (91.67%), specificity (98.33%), and accuracy (96.42%). The model could be used to effectively judge the state of illness and the prognosis.

The indolizidine skeleton is one of the most important structural motifs found in numerous biologically active molecules. [1][2][3][4] The development of efficient methods for the synthesis of indolizidine alkaloids has been the subject of intense research. [1][2][3][4] Recently, we have been devoted to the research of heterocyclizations using alkenoyl ketene dithioacetals as five-carbon 1,5-dielectrophiles [5,6] and ethyl isocyanoacetate as both a double Michael donor and a 1,3-dipole in a [5C+1C] annulation process for the construction of complex heterocyclic systems (Scheme 1). [6] As part of our studies in this area, we herein report a new synthetic strategy for the construction of the tricyclic indolizidine alkaloids 3 by an unprecedented [7C+1C] annulation to deliver the 8azabicyclo[5.2.1]dec-8-enes 2 from the easily available dialkenoyl ketene dithioacetals 1 as C 7 1,7-dielectrophiles (Scheme 1). [5][6][7][8] Initially, the reaction of the dialkenoyl ketene dithioacetal 1 a with ethyl isocyanoacetate was investigated to evaluate a tandem process involving a [7C+1C] annulation with 1 a as a C 7 1,7-dielectrophile (Table 1). It was found that treatment of the mixture of 1 a (1.0 mmol) and ethyl isocyanoacetate (1.1 equiv) with NaOH (1.0 equiv) in THF at room temperature for 0.5 hours gave the fused oxazoline 4 a [8a] in 71 % yield and 8-azabicyclo[5.2.1]dec-8-ene 2 a in 17 % yield (entry 1). According to our previous reports, [5a,b, 6] the formation of 2 a would involve a [7C+1C] annulation process.Although synthetic approaches to five-and six-membered carbocycles are legion, encompassing both cyclization and cycloaddition approaches, the synthesis of medium-sized carbocycles from acyclic precursors is quite challenging because of unfavorable entropic and enthalpic factors which preclude ring formation. [9] For the construction of eightmembered carbocycles, transition-metal-catalyzed/mediated higher-order cycloadditions involving [2+2+2+2], [4+4], [4+2+2], [5+2+1], and [6+2] [9a] ring-closing metathesis, [9b] and related intramolecular reactions have been reported. [9,10]

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Background Hip osteoarthritis is a common disabling condition of the hip joint and is associated with a substantial health burden. We assessed the epidemiological patterns of hip osteoarthritis from 1990 to 2019 by sex, age, and socio-demographic index (SDI). Methods Age-standardized rates (ASRs) were obtained for the incidence and disability-adjusted life years (DALYs) of hip osteoarthritis from 1990 to 2019 for 21 regions, encompassing a total of 204 countries and territories. The estimated annual percentage changes (EAPCs) of ASRs were calculated to evaluate the trends in the incidence and DALYs of hip osteoarthritis over these 30 years. Results Globally, from 1990 to 2019, the age-standardized incidence rate (ASIR) of hip osteoarthritis increased from 17.02 per 100,000 persons to 18.70 per 100,000 persons, with an upward trend in the EAPC of 0.32 (0.29–0.34), whereas the age-standardized DALY rate increased from 11.54 per 100,000 persons to 12.57 per 100,000 persons, with an EAPC of 0.29 (0.27–0.32). In 2019, the EAPCs of the ASIR and age-standardized DALY rate of hip osteoarthritis were positively associated with the SDI of hip osteoarthritis. In 1990 and 2019, the incidence of hip osteoarthritis was unimodally distributed across different age groups, with a peak incidence in the 60–64-year-old age group, whereas the DALYs increased with age. Conclusions The incidence and DALYs of hip osteoarthritis have been increasing globally. The EAPCs of the ASIR and age-standardized DALY rate were particularly significant in developed regions and varied across nations and regions, indicating the urgent need for governments and medical institutions to increase the awareness regarding risk factors, consequences of hip osteoarthritis.

Novel molecularly imprinted polymers (MIPs) based on the technique of surface-enhanced Raman scattering (SERS) were successfully prepared. Firstly, ZnO nanorods were fabricated with Ag by reduction of Ag on the surface of the ZnO nanorods. Then, ZnO/Ag heterostructures were used as the substrate, rhodamine 6G was used as the template molecule, acrylamide was used as the functional monomer, ethylene glycol dimethacrylate was used as the cross-linker, and 2,2'-azobis(2-methylpropionitrile) was used as the initiator to prepare the ZnO/Ag MIPs (ZOA-MIPs). Through characterization analysis, it was proved that the novel ZOA-MIPs exhibited excellent SERS properties and selectivity. Under the optimal conditions, there was a good linear relationship (R = 0.996) between the Raman signal (at 1654 cm) and the concentration of the templates, and the detection limit was 10 mol L. It was also proved that the ZOA-MIPs had the property of self-cleaning, resulting in good reusability. It is envisaged that the sensitivity of SERS coupled with the selectivity of MIPs could result in a promising chemosensor for practical applications.

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