Prevalence of Post-Stroke Cognitive Impairment in China: A Community-Based,Cross-Sectional Study

International hospital-based studies have indicated a high risk of cognitive impairment after stroke, evidence from community-based studies in China is scarce. To determine the prevalence of post-stroke cognitive impairment (PSCI) and its subtypes in stroke survivors residing in selected rural and urban Chinese communities, we conducted a community-based, cross-sectional study in 599 patients accounting for 48% of all stroke survivors registered in the 4 communities, who had suffered confirmed strokes and had undergone cognitive assessments via the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and Hachinski Ischemia Scale (HIS). Detection of PSCI was based on scores in these neuropsychological scales. Factors potentially impacting on occurrence of PSCI were explored by comparing demographic characteristics, stroke features, and cardiovascular risk factors between patients with and without PSCI. The overall prevalence of PSCI was 80.97% (95%CI: 77.82%-84.11%), while that of non-dementia PSCI (PSCI-ND) and post-stroke vascular dementia (PSD) was 48.91% (95%CI: 44.91%-52.92%) and 32.05% (95%CI: 28.32%-35.79%), respectively. Prior stroke and complications during the acute phase were independent risk factors for PSCI. The risk of recurrent stroke survivors having PSCI was 2.7 times higher than for first-episode survivors, and it was 3 times higher for those with complications during the acute phase than for those without. The higher prevalence of PSCI in this study compared with previous Chinese studies was possibly due to the combined effects of including rural stroke survivors, a longer period from stroke onset, and different assessment methods. There is an urgent need to recognize and prevent PSCI in stroke patients, especially those with recurrent stroke and complications during the acute phase.     

Solubilization of porcine intestinal alpha-glucosidases and evidence for the separate identities of isomaltase and limit dextrinase.

The results of a detailed comparison of the relative efficiencies of different procedures for solubilizing the membrane-bound α-glucosidases in hog intestinal mucosa are reported. Procedures for the selective solubilization of certain members of the complex group of α-glucosidases have been developed. The selective solubilization achieved permits the conclusion that separate α-glucosidases are involved in the hydrolysis of isomaltose and the α-limit dextrins formed from starch by α-amylase.     

Encapsidation of yeast killer double-stranded ribonucleic acids: dependence of M on L.

Virus-like particles containing either L or M double-stranded ribonucleic acid (dsRNA) were isolated from a killer toxin-producing strains of Saccharomyces cerevisiae (K+ R+). At least 95% of M- and 87% of L-dsRNA were recovered in virus-like particle-containing fractions. The major capsid polypeptides (ScV-P1) of both L and M virus-like particles were shown to be identical, and 95% of the cellular ScV-P1 was found in the virus-like particle-containing fractions. Since L-dsRNA encodes ScV-P1, provision of this protein for encapsidation of M-dsRNA defines at least one functional relationship between these dsRNA genomes and associates the L-dsRNA with the killer character. If encapsidation of M-dsRNA is essential for its replication or expression, then L-dsRNA plays an essential role in maintenance or expression of the killer phenotype. The relationship between the L- and M-dsRNA genomes would be analogous to that between a helper and a defective virus. The presence of only minor quantities or uncomplexed dsRNA and ScV-P1 suggests that their production is stringently coupled.     

Low-temperature conditional cell division mutants of Escherichia coli.

Fifteen low-temperature conditional division mutants of Escherichia coli K-12 was isolated. They grew normally at 39 degrees C but formed filaments at 30 degrees C. All exhibited a coordinated burst of cell division when the filaments were shifted to the permissive temperature (39 degrees C). None of the various agents that stimulate cell division in other mutant systems (salt, sucrose, ethanol, and chloramphenicol) was very effective in restoring colony-forming ability at 25 degrees C or in stimulating cell division in broth. One of these mutants, strain JS10, was found to have an altered cell envelope as evidenced by increased sensitivity to deoxycholate and antibiotics, as well as leakage of ribonulcease I, a periplasmic enzyme. This mutant had normal rates of DNA synthesis, RNA synthesis, and phospholipid synthesis at both the nonpermissive and permissive temperatures. However, strain JS10 required new protein synthesis in the apparent absence of new RNA synthesis for division of filaments at the permissive temperature. The division of lesion in strain JS10 is cotransducible with malA, aroB, and glpD and maps within min 72 to 75 on the E. coli chromosome.