中药材龟板和鳖甲中DNA的提取与扩增

中药材龟板和鳖甲中ＤＮＡ的提取与扩增王亚明，周开亚，吴平，徐珞珊（南京师范大学生物系，南京２１００９７；中国药科大学生药学研究室，南京２１０００９）龟鳖类药材在我国使用历史悠久，具补阴益气的功效。《中国药典》（１９９０年版）规定龟甲（龟板）的原动物为...     

Neuroendocrine responses to nicotine and stress: enhancement of peripheral stress responses by the administration of nicotine

Habitual smokers frequently report that when they are stressed smoking helps them to relax. One potential explanation for the reported stress ameliorating effect of smoking is that cigarette consumption (nicotine self-administration) may decrease the sympathetic autonomic nervous system activity which is associated with the stress response. In the present study, rabbits prepared with chronic vascular cannulae were used to study the effects of nicotine administation on plasma corticosterone, catecholamine (epinephrine, norepinephrine and dopamine) and glucose responses to physical restraint stress. Nicotine (0.025, 0.05 or 0.10 mg nicotine base/kg body weight) was administered for 10 days prior to the stress test to allow for the development of habituation/tolerance to its acute toxic effects. Independent administration of nicotine, or the application of the physical restraint stressor, resulted in increases in the plasma concentrations of corticosterone, epinephrine, norepinephrine, and glucose. Nicotine administration during restraint stress enhanced the increase in plasma corticosterone and epinephrine, as compared to the responses induced by either factor alone. The results suggest that the stress ameliorating effect of continued cigarette smoking, as reported by habitual smokers, is not due to a reduction in the activity of the peripheral sympathetic autonomic nervous system.     

Costello syndrome: Clinical phenotype,genotype, and management guidelines

Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence‐based guidelines due to the lack of data for this rare condition.     

Branhamella (Neisseria) catarrhalis: criteria for laboratory identification.

Eleven clinically significant isolates of Branhamella catarrhalis grew well on modified Thayer-Martin medium and produced beta-lactamase, but did not grow on nutrient agar at 22 degrees C. Minimum inhibitory concentrations of vancomycin, colistin, and trimethoprim were found to be higher than the concentrations of these antibiotics in modified Thayer-Martin medium. The criteria necessary for laboratory identification of B. catarrhalis are discussed.     

Epidemiology of group C rotavirus infection in Western New York women of childbearing age.

Umbilical cord serum samples (380), an average of 10 per month for 3 years (1990 to 1992), were tested by indirect immunofluorescence assay for group C rotavirus immunoglobulin G. Thirty percent were positive, suggesting that approximately one-third of women of childbearing age in western New York have experienced group C rotavirus infection.     

Presence of hydrogen peroxide in media used for cultivation of Neisseria gonorrhoeae.

Defined complex media used for cultivation of Neisseria gonorrhoeae were tested for the presence of H2O2 by both a spectrophotometric and a polarographic assay. H2O2 (35 to 165 microM) was present in all media tested. In the defined media, H2O2 was generated by the interaction of cysteine with other amino acids. The addition of the chelator 8-hydroxyquinoline prevented formation of detectable H2O2, suggesting that metal ions were necessary. The persistence of H2O2 varied greatly among different media. Medium components which affected the presence of H2O2 were pyruvate, oxalacetate, and sodium sulfite. Sodium sulfite also generated superoxide radical. In liquid medium containing H2O2, the endogenous gonococcal catalase present in an inoculum of about 2 X 10(7) colony-forming units/ml destroyed detectable H2O2. The long lag phase which resulted from a 10-fold lower inoculum could not be shortened by the addition of exogenous catalase. Small amounts of residual H2O2 in agar plates of complex medium affected the viability of gonococci which had been suspended in buffer and incubated for 60 min at 37 degrees C. Addition of pyruvate or catalase increased viable counts in medium containing H2O2.     

Distribution of an antigenically related iron-regulated protein among the Neisseria spp.

Several iron-regulated proteins of Neisseria gonorrhoeae have been reported. One of these, a 37,000-molecular-weight protein (37K protein), appears to be common to all gonococcal isolates. Recently, the occurrence of a similar protein has also been noted in N. meningitidis. The gonococcal 37K protein has been purified and used to produce both rabbit monospecific antiserum and murine monoclonal antibodies. Using these antibody reagents, we analyzed 57 strains from nine species of Neisseria and the closely related organism Branhamella catarrhalis for the presence of proteins antigenically related to the gonococcal 37K protein. Strains grown on medium with low iron content were probed for antigenic reactivity by Western blot techniques and an enzyme-linked immunosorbent assay. Proteins which cross-reacted with the rabbit monospecific antiserum were designated as AgR-37K proteins. The data indicated that the AgR-37K proteins were conserved among the 40 strains of N. gonorrhoeae, N. meningitidis, N. lactamica, and N. cinerea tested. Seventeen strains from other species of Neisseria and Branhamella did not express AgR-37K proteins with the exception of one N. subflava isolate. All AgR-37K proteins appeared to be regulated by the amount of available iron in the growth medium. Murine monoclonal antibodies were used to probe the antigenic heterogeneity of the AgR-37K proteins from different Neisseria spp. Two of seven monoclonal antibodies were broadly cross-reactive, recognizing the AgR-37K proteins from all species examined. The remaining five monoclonal antibodies were more discriminating, recognizing the AgR-37K proteins from certain species. The antigenic conservation of these AgR-37K proteins, particularly among the pathogenic members of the genus Neisseria, may imply that these proteins serve a common function in pathogenicity.     

Changes in triceps surae muscle architecture with sarcopenia

AIM: To investigate whether sarcopenia was evenly distributed among the three components of the triceps surae (TS) muscle group. METHODS: Muscle volume (VOL), fibre fascicle length (Lf), pennation angle (theta) and physiological cross-sectional area (PCSA = VOL/Lf) were measured in vivo for the lateral (GL) and medial (GM) heads of the gastrocnemius muscles and for the soleus muscle (SOL), in 15 young males (YM, aged 25.3 +/- 4.5 years) and 12 elderly males (EM aged 73.8 +/- 4.4 years). RESULTS: In the EM, VOL of all three muscles was significantly smaller than in the YM; differences were: 27% for the GL (P < 0.01), 29% for the GM (P < 0.01) and 17% for the SOL (P < 0.05). In total, TS VOL was 22% smaller in EM than in YM (P < 0.01). In the EM, values of theta were significantly smaller than in the YM; by 15-18% for the GL, GM and SOL (P < 0.05). In the EM, Lf of the GM was 16% smaller than in the YM (P < 0.01); no significant differences were found in the other muscles. PCSA of the GL and GM were both found to be smaller in EM by 19% (P < 0.01) and 14.5% (P < 0.05), respectively. No difference was observed in the SOL PCSA between YM and EM. Interestingly, probably because of the prevalent contribution of the SOL to PCSA distribution of each muscle to the TS PCSA, the relative TS PCSA was not different between YM and EM. Furthermore, the Lf/muscle length ratio did not differ between YM and EM. CONCLUSION: The present study shows that the relative PCSA composition of the TS is maintained with ageing and that the PCSA is scaled down harmonically with the decrease in muscle volume and fascicle length. Such observation suggests that the relative contribution of the components of the TS muscle to the total force developed by this muscle group is maintained with ageing.     

Inhibitory Action of Fatty Acids on the Growth of Neisseria gonorrhoeae

Fatty acids of various chain lengths (C(1) to C(24)) were examined for their effects on growth, oxygen consumption, and in vitro reduced nicotinamide adenine dinucleotide oxidase activity of Neisseria gonorrhoeae CS-7. The growth inhibition caused by saturated fatty acids increased with increasing chain length to a maximum with palmitic acid (C(16)). Stearic acid (C(18)) and longer saturated fatty acids showed little inhibition of growth. However, unsaturated fatty acids of chain length C(16) to C(20) were inhibitory. Similar inhibition was observed with Bacillus subtilis and a deep rough mutant of Salmonella typhimurium. Wildtype S. typhimurium and Pseudomonas aeruginosa were more resistant to medium-chain (C(7) to C(10)) fatty acids and completely resistant to long-chain (C(12) to C(18)) fatty acids. Thus, sensitivity of N. gonorrhoeae to long-chain fatty acids appears to be related to the permeability of the outer membrane. Growth inhibition by short-chain (C(1) to C(6)) fatty acids was pH dependent; inhibition of growth increased with decreasing pH. Saturated fatty acids inhibited oxygen consumption by log-phase cells of N. gonorrhoeae. This inhibition increased with increasing chain length to a maximum observed with myristic acid (C(14)). Whereas stearic acid (C(18)) had little effect upon oxygen consumption, unsaturated C(18) fatty acids were inhibitory. An in vitro inhibition of reduced nicotinamide adenine dinucleotide oxidase activity by saturated (C(1) to C(12)) and unsaturated (C(16) to C(20)) fatty acids was also observed. Although the inhibitory concentrations were generally higher than those required to inhibit growth or oxygen consumption, an inhibition of electron transport may be partially responsible for the observed growth inhibition.