Quantitative analysis of synaptic distribution along thalamocortical axons in adult mouse barrels

Quantitative data on thalamocortical synapses in adult mouse barrels have been obtained largely by using lesion-nduced degeneration to label thalamic afferents. By the time degenerating axons can be identified with the electron microscope, they have broken up into many separate pieces, making it impossible to assess the distribution of synapses along unbroken lengths of afferent. Here, this deficiency is rectified by examining intact lengths of axon labeled by the injection of biotinylated dextran amine into ipsilateral thalamus. Serial thin section reconstructions were analyzed to determine the numbers of synapses per axon length made with dendritic spines vs. shafts and the locations of synapses with respect to axonal varicosities. Results for seven axonal segments from six mice showed an average of 0.2 synapses/microm; 80% were made with spines and 20% with dendritic shafts. Just over two-thirds of axonal varicosities formed one synapse; most of the remainder formed two and rarely three, whereas 8% formed none. Although most synapses occurred at varicosities (88%), more than 12% were made at cylindrically shaped regions of the reconstructed axonal segments. These results serve as a caveat for the use of light microscopy to quantify synapses, wherein the usual approach is to equate one varicosity with one synapse. For thalamocortical afferents to mouse barrels, equating one varicosity with one synapse would prove to be incorrect more than 30% of the time and would exclude the roughly 12% of synaptic connections made at cylindrical regions of thalamocortical afferents.     

Self-enhancing effects of exposure to thin-body images

OBJECTIVE: This study examines the effect of thin-body media images on mood, self-esteem, and self-image ratings of restrained and unrestrained eaters. A secondary purpose was to examine whether these effects were influenced by exposure duration. METHOD: Under the guise of a perception study, participants were exposed to thin-body or control advertisements (e.g., perfume bottles) for either 7 or 150 ms and then completed a questionnaire packet. RESULTS: Restrained eaters reported more favorable self-image and social self-esteem (but not appearance self-esteem) scores after exposure to thin-body images than after exposure to control advertisements. The self-image and social self-esteem scores of unrestrained eaters were unaffected by advertisement type, but their appearance self-esteem scores were lower after exposure to thin-body advertisements. No differences were found for mood ratings and total self-esteem. DISCUSSION: We discuss restraint status as a moderator of the effects of thin-body images on women's body image.     

The influence of puberty and ethnicity on awareness and internalization of the thin ideal

OBJECTIVE: This study examined the effects of puberty and ethnicity on awareness and internalization of the thin ideal. METHOD: Fourth and fifth-grade girls (N = 67) and their parents (N = 67) completed questionnaires assessing demographic variables, eating pathology, pubertal development, and awareness and internalization of the thin ideal. RESULTS: Girls in pre/early puberty did not differ significantly from girls in mid/late puberty on awareness of the thin ideal; however, more developed girls had significantly greater internalization of the thin ideal. Caucasian and non-Caucasian girls also did not differ on awareness of the thin ideal, but non-Caucasian girls reported greater internalization. No significant interactions between race and puberty existed on the dependent variables. DISCUSSION: Factors specifically related to puberty seem to be key to girls' development of disordered eating attitudes. The effect of puberty on increased internalization of the thin ideal cannot be explained by increased age or awareness of the thin ideal.     

薄层荧光扫描法测定吴茱萸药材及其制剂中5种生物碱的含量

目的：用薄层荧光扫描法测定吴茱萸及加味左金丸中5种生物碱:羟基吴茱萸碱(hydroxyevodiamine, I)、N-甲酰二氢吴茱萸次碱(N-formyldihydrorutaecarpine, II)、吴茱萸酰胺甲(goshuyuamide-I, III)、吴茱萸碱（evodiamine, IV)及吴茱萸次碱(rutaecarpine, V)。方法：在高效硅胶薄层板上点样后,二次展开。展开剂:（1）氯仿—石油醚—甲醇—环己烷（5∶3∶0.4∶0.4）;(2)氯仿—甲醇(4.1∶0.3)。展开后用浓盐酸衍生化,荧光扫描测定。结果：各生物碱的线性范围在20.5～245 ng,回收率为96.8%～104.5%,并用此法测定了不同产地吴茱萸及不同批号的加味左金丸中生物碱的含量。结论：方法灵敏度高、样品用量少,可为寻找和利用植物资源,控制生药及方剂质量提供科学依据。     

两色金鸡菊醇提物的质量标准研究

目的建立两色金鸡菊醇提物的质量标准。方法通过薄层色谱法(TLC)、水分测定、炽灼残渣测定、紫外分光光度法和高效液相色谱法对两色金鸡菊醇提物进行质量控制。结果薄层色谱显示供试品与对照品绿原酸斑点在相同的位置上显相同颜色,供试品鉴别分离出马里苷、黄酮奥卡宁和奥卡宁3个主要成分;两色金鸡菊醇提物的水分不得超过15%;炽灼残渣不得超过16%;两色金鸡菊醇提物中绿原酸含量(C_(16)H_(24)O_(12))不得少于0.8%;flavanomarein含量(C_(21)H_(22)O_(11))不得少于4%;marein含量(C_(21)H_(22)O_(11))不得少于8.5%;3,5-二咖啡酰基奎宁酸含量(C25H24O12)不得少于0.5%;总黄酮含量不得低于9%;总酚酸含量不得低于28.0%。结论根据《中国药典》中药质量标准研究制定技术要求建立了一套完整的两色金鸡菊醇提物质量标准。建立了TLC可定性鉴别两色金鸡菊醇提物中的各主要成分,通过一测多评法可定量控制两色金鸡菊醇提物中绿原酸、flavanomarein、marein和3,5-二咖啡酰基奎宁酸的含量,建立紫外分光光度法可测定两色金鸡菊醇提物中的总黄酮、总酚酸的含量。     

Carotid body thin slices: responses of glomus cells to hypoxia and K(+)-channel blockers

We describe the rat carotid body thin slice preparation, which allows to perform patch-clamp recording of membrane ionic currents and to monitor catecholamine secretion by amperometry in single glomus cells under direct visual control. We observed several electrophysiologically distinct cell classes within the same glomerulus. A voltage- and Ca(2+)-dependent component of the whole cell K(+) current was reversibly inhibited by low P(O(2)) (20 mmHg). Exposure of the cells to hypoxia elicited the appearance of spike-like exocytotic events. This response to hypoxia was reversible and required extracellular Ca(2+) influx. Addition of tetraethylammonium (TEA, 2-5 mM) to the extracellular solution induced in most (>95%) cells tested a secretory response similar to that elicited by low P(O(2)). Cells non-responsive to hypoxia but activated by exposure to high external K(+) were also stimulated by TEA. A secretory response similar to that of hypoxia or TEA was also observed after treatment of the cells with iberiotoxin to block selectively maxi-K(+) channels. Our data further support the view that membrane ion channels are critically involved in sensory transduction in the carotid body. We demonstrate that in intact glomus cells inhibition of voltage-dependent K(+) channels can contribute to initiate the secretory response to low P(O(2)).     

Evaluation of the immunomodulatory and DNA protective activities of the shoots of Cynodon dactylon

Ethnopharmacological relevance

Fresh juice of Cyanodon dactylon known as ‘durva’ grass is employed in India as a rejuvenator and for wound healing.

Aim of the study

To validate the traditional use of the herb through evaluation of DNA protective activity in vitro and immunomodulatory activity in vivo.

Materials and methods

Fresh juice of the grass was prepared as indicated for use in traditional medicine and standardized for solid content. Its total phenol content was estimated by Folin–Ciocalteau method. Freshly prepared juice was investigated for its effect on doxorubicin-induced DNA damage in vitro. Its immunomodulatory activity was tested on balb/c mice by the humoral antibody response which was determined by haemagglutination antibody titer and spleen cell assay.

Results

Fresh juice of Cyanodon dactylon of 1.46% (w/w) solid content had a phenolic content of 47 ± 0.33 mg/kg GAE. At doses equivalent to 50, 100 and 200 mg total solids/kg body weight the juice protected human DNA against doxorubicin-induced DNA damage as demonstrated in DNA spectral studies, where the ratio of absorbance of DNA at 260 and 280 nm in samples pretreated with the juice was 1.66, 1.53 and 1.63 respectively, while it was 1.37 for DNA treated with doxorubicin only. This indicates nucleic acid purity in the Cynodon dactylon treated samples. Oral administration of the juice at 250 and 500 mg/kg in balb/c mice increased humoral antibody response upon antigen challenge, as evidenced by a dose-dependent, statistically significant increase in antibody titer in the haemagglutination antibody assay and plaque forming cell assay.

Conclusions

The present report demonstrated the DNA protective activity and immunomodulatory property of the fresh juice of Cynodon dactylon validating the traditional use of the herb as a ‘rasayana’ in ayurvedic system of medicine.     

The Influence of Oxidation on the Magnetic,Electrical, and Mechanical Properties of Co40Fe40Yb20 Films

A typical body-centered cubic (BCC) CoFe(110) peak was discovered at approximately 2θ = 44.7°. At 2θ = 46°, 46.3°, 47.7°, 55.4°, 54.6°, and 56.4°, the Yb₂O₃ and Co₂O₃ oxide peaks were visible in all samples. However, with a heat treatment temperature of 300 °C, there was no typical peak of CoFe(110). Electrical characteristics demonstrated that resistivity and sheet resistance reduced dramatically as film thickness and annealing temperatures increased. At various heat treatments, the maximum hardness was 10 nm. The average hardness decreased as the thickness increased, and the hardness trend decreased slightly as the annealing temperature was higher. The highest low-frequency alternative-current magnetic susceptibility (χ_ac) value was discovered after being annealed at 200 °C with 50 nm, and the optimal resonance frequency (f_res) was discovered to be within the low-frequency range, indicating that the Co₄₀Fe₄₀Yb₂₀ film can be used in low-frequency applications. The maximum saturation magnetization (Ms) was annealed at 200 °C for 50 nm. Thermal disturbance caused the Ms to decrease as the temperature reached to 300 °C. The results show that when the oxidation influence of as-deposited and thinner films is stronger than annealing treatments and thicker thickness, the magnetic and electrical properties can be enhanced by the weakening peak of the oxide, which can also reduce interference.     

刃厚皮片联合微型带真皮下血管网全厚皮片修复截瘫褥疮

目的：应用刃厚皮片联合微型真皮下血管网全厚皮片修复截瘫褥疮。方法：对6例截瘫褥疮，增强全身支持治疗，彻底清除褥疮的炎性肉芽组织及坏死组织后，采用刃厚皮片联合微型真皮下血管网全厚皮片修复．结果：5例Ⅰ期愈合，1例Ⅱ期愈合。结论：本法操作简单，愈合较快，具有一定的耐磨性，为进一步皮瓣修复奠定了基础，是修复难治性截瘫褥疮较理想的方法．     

不同炮制方法对瑞香狼毒化学成分的影响

目的：考察不同炮制方法对瑞香狼毒化学成分的影响。方法采用系统预试法,包括理化和薄层色谱（TLC）鉴别,检测瑞香狼毒生品和炮制品中化学成分的异同。结果（1）瑞香狼毒生品和炮制品中均含有糖类、苷类、酚类、鞣质类、有机酸类、皂苷类、黄酮类、甾体、三萜类、香豆素内酯类成分,可能含有挥发油、油脂类成分。水提液中酚类、鞣质类和皂苷类成分有差异。（2）水提液中,奶制品的黄酮类成分含量较低;乙醇提取液中,生品和三种炮制品的黄酮类成分基本相同。（3）水提取液中,醋制品的香豆素内酯类成分含量较高;乙醇提取液中,奶制品的香豆素内酯类成分含量较低。（4）水提取液中,生品的萜类成分含量较高;乙醇提取液中,生品和奶制品的萜类成分含量较高。结论不同炮制方法对瑞香狼毒的化学成分都有影响。