RESUMEN
Stereoselective construction of γ- and δ-stereocenters in carbonyl compounds is a pivotal objective in asymmetric synthesis. Here, we report chiral bifunctional oxazoline-pyridone ligands that enable enantioselective palladium-catalyzed remote γ-C-H (hetero)arylations of free cycloalkane carboxylic acids, which are essential carbocyclic building blocks in organic synthesis. The reaction establishes γ-tertiary and α-quaternary stereocenters simultaneously in up to >99% enantiomeric excess, providing access to a wide range of cyclic chiral synthons and bioactive molecules. The sequential enantioselective editing of two methylene C-H bonds can be achieved by using chiral ligands with opposite configuration to construct carbocycles containing three chiral centers. Enantioselective remote δ-C-H (hetero)arylation is also realized to establish δ-stereocenters that are particularly challenging to access using classical methodologies.
RESUMEN
OBJECTIVE: This study aims to compare the difference and the change trend of Muscle Architecture Parameters (MAP) between spastic and normal muscle tone patients after stroke, and analysis the application and value of Muscle Architecture Parameters in evaluating spasticity after stroke. METHODS: 41 stroke patients were divided into spastic group (26 cases), normal muscle tone control group (15 cases). Modified Ashworth Scale (MAS) was applied in both groups for assessing muscle tone of lower limbs (no influence, contralateral). Muscle architectural parameters of ultrasound measurement include muscle thickness, fascicle length and pennation angle. The difference of three muscle architectural parameters between the affected side and the contralateral side in spastic group and the difference of MAS and three muscle architectural parameters between spastic group and normal control group were compared. RESULTS: MAS score, Pennation Angle (PA) and Muscular Thickness (MT) value of MAP in spastic group were significantly higher than the control group, Fascicle length (FL) is significantly lower than the control group (P < 0.05). In spastic group, MAS score, PA and MT value of MAP of affected side muscle was substantially higher than that of contralateral, FL value significantly lower than that of contralateral (P < 0.05). There was positive correlation between MAS and PA and MT but was negative correlation between MAS and FL, rank correlation coefficient test was statistical significant (p < 0.05). Logistic multivariate regression analysis showed that spasticity can lead PA and FL to change (p < 0.05), there is no clear correlation between MT and spasticity occurs (P > 0.05). CONCLUSION: MAP has a better sensitivity in evaluating muscle tone between spastic patients and non-spastic patients, and degrees of spasticity have a clear corresponding exponential relationship to MAP. Combing MAS and MAP can assess muscle tone more objectively and accurately because subtle changes can be observed by testing values of architecture parameters that compensating for the shortcomings of MAS in reliability and validity. Thus it is helpful for guiding clinical antispastic practice.
RESUMEN
OBJECTIVE: To study the epidemiological and etiological characteristics of typhoid and paratyphoid fever in high epidemic areas. METHODS: Reported data on typhoid and paratyphoid fever during 1988-2007 in Ningbo were analyzed epidemiologically. Shellfish from the market was collected for laboratory testing and Salmonella typhi strains collected from the patients were also studied. RESULTS: Number of reported cases on both typhoid and paratyphoid fever was 19 404 with 7 deaths, from 1988 to 2007. The annual mean incidence was 17.68 per one hundred thousand with the fatality rate as 0.36 per thousand. Most cases were among adults aged 20-50 years and an obvious regional distribution was observed with high incidence seen in winter and spring. Since 1990s, the advantage strain had changed from Salmonella typhi to Salmonella paratyphi A. Etiologic studies showed that raw Anadara subcrenata and oyster were the main risk factors. One Salmonella paratyphi A strain was detected in both Anadara subcrenata and oysters collected from the market, which contained TEM-1 drug resistance gene. PFGE genotyping showed that PFGE-X2 was the strain which causing pandemic in Ningbo. CONCLUSION: Eating contaminated raw shellfish like oysters and hairy clams was the primary risk factor, responsible for the outbreaks. Salmonella paratyphi A was the advantages pandemic strain in Ningbo. Strategies as supervision on personal hygiene and health education should be strengthened.
