用细口径反相柱HPLC分离多种前列腺素

HPLC与放射性同位素联用,可同时分离鉴定多种花生四烯酸代谢产物。目前国外一般是使用普通口径(4.6 mm)的反相柱,以30%左右乙腈为流动相,流速为1～3 ml/min。这种HPLC方法乙腈用量较大,费用太贵,不适合国内实验室常规操作。据报道,细口径     

Wallerian degeneration in a patient with Schilder disease: MR imaging demonstration

Wallerian degeneration in the corticospinal tract was demonstrated by magnetic resonance (MR) imaging in a patient with Schilder disease. The histochemical stages of myelin breakdown that allow its demonstration by MR imaging are reviewed.     

Ocular central nervous system lymphoma mimicking choroidal neovascularization.

Two patients evaluated for metamorphopsia were noted to have inferotemporal retinal pigment epithelium elevations formed by a yellowish lesion. Fluorescein angiography showed granular hyperfluorescence with late leakage, which was interpreted as an occult choroidal neovascularization. One patient underwent photodynamic therapy. In both patients, neither vitreous cells nor neurologic manifestations were evident on presentation. Subsequent neurological signs appeared that prompted performance of brain imaging, which confirmed a space-occupying lesion. In both patients, the tumor was proven on histopathologic examination of brain tissue to be central nervous system lymphoma. Awareness of other possible underlying pathologies is warranted in cases of atypical choroidal neovascularization.     

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

Objective

To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA).

Methods

Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey''s manual of determinative bacteriology.

Results

Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key.

Conclusions

The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.     

A comparative histological analysis of human pulp following direct pulp capping with Propolis, mineral trioxide aggregate and Dycal

Background:  Permanent teeth pulp exposures have traditionally been treated with calcium hydroxide pulp capping. The aim of this study was to investigate the response of human pulp tissue which were mechanically exposed to a new material, Propolis and compare it with two existing and commonly used pulp capping agents (mineral trioxide aggregate and Dycal).
Methods:  Thirty-six intact human premolars were mechanically exposed. Teeth were divided into six groups of 6 teeth each and were capped with Propolis, mineral trioxide aggregate and Dycal. Final restoration was done with posterior composite resin using light cured glass ionomer cement as a liner. The teeth were then extracted on the 15th or the 45th day and processed for histological evaluation.
Results:  Differences in inflammatory response and dentine bridge formation of the exposed pulp to the three different materials were statistically calculated using chi-square test and were found to be non-significant. There was more pulp inflammation in teeth treated with Dycal than with Propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp capping material than teeth treated with Dycal on the 45th day.
Conclusions:  The response of pulps to Propolis as a pulp capping agent was comparable to MTA and Dycal.