Phenotypic variation and diversity of Magnolia sprengeri Pamp. in native habitat.

The population of Magnolia sprengeri individuals deceased drastically in the late 20th century because of the widespread harvest for traditional Chinese medicinal recipes. In this study, the levels of phenotypic variation and the genetic structure of 2 populations of M. sprengeri were estimated. The phenotypic variation of M. sprengeri characteristics was nonsynchronous, with a coefficient of variation for 37 characters from 9.55-35.87%. The variance stabilizing transformation value ranged from 0.034-52.344%. The variation contribution within the population was greater than the contribution among the population; the among-population rate was 2.864%, while the within-population rate was 15.849%; values of repeatability for among-population and within-population were 0.430 and 0.098, respectively. This indicates that more variation arose from within-population and that population repeatability was much greater than individual repeatability. Variation in the flower organ was greater than that in the leaf organ; this means that vegetative variation was more stable than reproductive variation. Variation in the southern population was greater than that in the northern population.

Cancer therapy improvement with mesoporous silica nanoparticles combining photodynamic and photothermal therapy.

In this work, we develop novel mesoporous silica composite nanoparticles (hm-SiO2(AlC4Pc)@Pd) for the co-delivery of photosensitizer (PS) tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) and small Pd nanosheets as a potential dual carrier system to combine photodynamic therapy (PDT) with photothermal therapy (PTT). In the nanocomposite, PS AlC4Pc was covalently conjugated to a mesoporous silica network, and small Pd nanosheets were coated onto the surface of mesoporous silica by both coordination and electrostatic interaction. Since small Pd nanosheets and AlC4Pc display matched maximum absorptions in the 600-800 nm near-infrared (NIR) region, the fabricated hm-SiO2(AlC4Pc)@Pd nanocomposites can generate both singlet oxygen and heat upon 660 nm single continuous wavelength (CW) laser irradiation. In vitro results indicated that the cell-killing efficacy by simultaneous PDT/PTT treatment using hm-SiO2(AlC4Pc)@Pd was higher than PDT or PTT treatment alone after exposure to a 660 nm CW-NIR laser.

The stress-bearing ability of mucosa in complete denture-wearers.

OBJECTIVE: The purpose of this study was to investigate the stress-bearing ability of mucosa in complete denture-wearers. METHODS: The maximum bite force (MBF) was obtained in 31 voluntary complete denture-wearers with a miniature bite force instrument and a set of central bearing devices. The projective stress-bearing area in the mandible (PAM) was measured through the impression surface of the mandibular complete denture. The authors evaluated the stress-bearing ability (SBA) of mucosa in complete denture-wearers by the formula MBF/PAM. RESULTS: The results showed that there was a significant positive correlation between the MBF (the mean was 15.13 kg in men and 11.39 kg in women) and the PAM (the mean was 17.15 cm2 in men and 14.46 cm2 in women) and that there was no significant difference between the mean of the SBA in men (0.89 kg/cm2) and the mean of the SBA in women (0.79 kg/cm2). The mean value of the maximum pressure borne by the mandibular edentulous region was 82 kPa (0.84 kg/cm2). CONCLUSIONS: The SBA may become a valuable parameter for the design of both occlusion and reinforcement in the denture construction and for the selection of the maximum load in mechanical tests of complete dentures.

[Evaluation of plasma neuropeptide Y levels in patients with congestive heart failure].

Plasma neuropeptide Y (NPY) was measured by radioimmunoassay in 43 patients with congestive heart failure (CHF) and 20 healthy control subjects. The results showed that plasma NPY levels were elevated in patients with CHF compared with control subjects (366 +/- 28 ng/L VS. 89 +/- 22 ng/L, P < 0.001). There was a close relationship between the severity of CHF and plasma NPY levels. The severer the CHF, the higher the NPY level. In addition, 20 of the 43 patients with symptoms improved after treatment for heart failure were followed. The results indicated a significant decrease of plasma NPY levels (333 +/- 42 ng/L VS. 157 +/- 25 ng/L, P < 0.01) in these patients. Furthermore, multiple logistic regression analysis demonstrated that the presence and severity of CHF were related to plasma NPY levels significantly and independently. Because of its potent vasoconstrictive and negative cardiac inotropic effects, NPY might be involved in the pathophysiology of CHF. Plasma NPY levels might be taken as a prognostic indicator in patients with CHF, but further investigation is needed.

[Effects of the orientation of occlusal plane on EMG of masticatory muscles in complete denture wearers].

The occlusal plane was designed as parallel to Camper's line (the standard dentures) and 5 degree inclined upward, downward laterally and anterior-posterior for comparing the activities of masticatory muscles. Following results were obtained: (1) the amplitude of the masseter (Mm) and the anterior temporalis (Ta) muscles with standard dentures biting in intercuspal position were the highest among those with other dentures, (2) during unilateral chewing with standard dentures, the average amplitude of the anterior digastric muscles (Da) on the balanced side was higher than that on the working side, but the amplitude values of the Mm and the Ta on the working side were significantly lower than those on the opposite side, (3) to incline the plane forward or backward may cause the activity of the Da increased in the balanced side and (4) to incline the plane right or left the amplitude of Ta and Mm between the working and the balanced side was not significant different.

Preliminary study of electromyographic characteristics for distinguishing centric relation and protrusion in edentulous patients.

The mean voltages of the masseter and anterior temporal muscles of 30 Chinese edentulous patients were recorded in centric relation and protrusive positions (from 1 mm to 4 mm anterior to centric relation) under two given occlusal force conditions. It was found that the mean ratio of individual voltages of the anterior temporal muscles to the masseter muscles was equal to or greater than 1.2 in centric relation, but the ratio was less than 1.2 in protrusive positions in most of the subjects. The results demonstrated that the ratio of voltages of the anterior temporal muscles to masseter muscles may be a reliable parameter for distinguishing centric relation from protrusion in Chinese edentulous patients.

[Protrusive condyle path in edentulous patients].

The inclinations of condyle path of 32 edentulous patients were measured by taking protrusive relation record at the protrusive positions of 2, 4, 6, and 8 mm. The relations between the condylar shift and the protrusive distance were analysed. It was found that the inclination of condyle path was varied with individual, sex and protrusive distance. The shape of protrusive condyle path was like a section of parabola curved forward and downward. The results demonstrate that a small free gliding area in centric occlusion is necessary in complete dentures to fit the physiological movement of temporomandibular joints. The position of rotation center of protrusive movement requires further study.

[Resources of Chinese materia medica in shennonjia].

There are 2023 species of Chinese materia medica in Shennonjia, belonging to 300 families and 974 genera, of which 1800 (including subspecies) are plants, 213 animals and 10 minerals. Protection, exploitation and utilization of these resources have been discussed.