[Effect of paraquat on the expression of a disintegrin and metalloproteinase-17 in A549 cells]

Objective: Construct a paraquat (PQ) cell fibrosis model in vitro, observe the effect of PQ on the expression of a disintegrin and metalloproteinase-17 (ADAM17) in A549 cells, and explore the role of ADAM17 in the pulmonary fibrosis induced by PQ poisoning. Methods: A549 cells are divided into normal control group, different concentration of PQ groups, CCK-8 is used to detect cell viability, screening concentration and time of PQ, cell morphology is observed under microscope; Enzyme-linked immunosorbent assay (ELISA) detectes fibrosis markers of collagen type I (Col I) and fibronectin (FN) expression. Establishment of cell model of fibrosis; distribution by immunocytochemical detection of ADAM17 in A549 cells, Reverse transcription-polymerase chain reaction and Western blot are used to detect the expression of ADAM17 mRNA and protein. Results: 1. With the increase of PQ concentration and the prolongation of the action time, the activity of A549 cells decreased (P< 0.05) , which is dose-dependent and time dependent. 2.The normal A549 cells fusion is paving stone growth and arranged more closely. After PQ induction, the cell arrangement was loose, the intercellular connection became loose, and some cells dissolved and died. 3.ELISA showed that with the increase of PQ concentration, the expression of Col I and FN increased (P<0.05) , and Col I and FN expression gradually increased with the prolongation of PQ time (P<0.05) , and the fibroblast model is successfully established. 4. Immunocytochemistry showes that ADAM17 is expressed in the cytoplasm of A549 cells. 5. RT-PCR and Western blot showed that the expression of ADAM17 mRNA and protein increased significantly with the increase of PQ concentration (P<0.05) , which is most obvious at PQ 200 μmol/L. With the prolonged action of PQ, the expression level of ADAM17 mRNA and protein also increased significantly (P<0.05) , and reached the peak in 24 h. Conclusion: PQ can induce morphological changes of alveolar epithelial cells, cause cell damage, and successfully establish a cell fibrosis model, which has a dose and time dependence on the toxicity of A549 cells. ADAM17 is overexpressed in the A549 cells induced by PQ and may be involved in the process of pulmonary fibrosis induced by paraquat.

Optimal treatment for distal ureteral calculi: extracorporeal shockwave lithotripsy versus ureteroscopy

BACKGROUND

The optimal treatment for distal ureteral calculi remains controversial. We present data from our institution to compare the efficacy of extracorporeal shockwave lithotripsy (SWL) and ureteroscopy with different lithotripsy modalities (URSL).

METHODS

From January 1994 to September 1997, 954 distal ureteral calculi were treated at our institution using in situ SWL (Siemens Lithostar) in 524 patients and ureteroscopy (Wolf 8.0F instrument and Swiss Lithoclast) in 430 patients. Stone sizes and patient ages were similar in these two groups.

RESULTS

In the SWL group, the 3-month stone-free rate was 87%, and the effectiveness quotient (EQ) was 68.7%. In the URSL group, there was a 96% stone-free rate with an EQ of 92.1%. The SWL treatment was more expensive than URSL.

CONCLUSION

At our institution, ureteroscopy is more efficacious than SWL for the treatment of distal ureteral calculi. In selected patients who had stones >10 mm with evidence of impaction and severe colic pain, we strongly suggest that URSL is the best choice.

A perfume odour-sensing system using an array of piezoelectric crystal sensors with plasticized PVC coatings

Using PVC polymer as membrane matrix and di-n-octylphenyl phosphate (DOPP) as plasticizer, a piezoelectric crystal sensor (PCS) array with 12 adsorptive materials selected from 68 compounds by cluster analysis has been constructed as a perfume odour-sensing system. The frequency shift data obtained from the sensor array responding to four commercial perfume odours are first autoscaled and then treated by principal component analysis. The experimental results show that the plasticized PVC membrane PCS array provides improved performance of pattern recognition compared with the single adsorptive coating PCS array. The frequency shift response characteristics of these sensors have been investigated experimentally. The proposed sensor array has also been applied to the classification of commercial spirituous liquor, wine and soft drink samples, as well as aliphatic alcohol homologues and isomers.

Electron microscopic and immunohistochemical findings in a case of olfactory neuroblastoma

A case of olfactory neuroblastoma is reported. Light microscopic examination showed various arrangements of poorly differentiated tumour cells forming either uniform sheets or convoluted cords of multiple cell layers orientated toward a richly vascular stroma. Electron microscopic examination showed the presence of abundant cytoplasmic filaments and processes, and dense core endocrine vesicles ranging from 100-160 nm in diameter in both the perinuclear region and tumour cell processes. Immunohistochemical staining was positive in most of the tumour cells for neuron specific enolase, and in a few cells for S-100 protein, vimentin, and serotonin, but staining for desmin and keratin produced no reaction.

[A clinical study of 50 cases of Legionnaires disease]

The clinical features and X-ray manifestations of 50 cases of legionnaires disease were analysed. 8 cases might be due to nosocomial infection through breathing in flying particles of the saliva or phlegm. According to the main clinical features, this disease could be divided into common pneumonia type; acute gastroenteritis type; encephalopathy type; shock type; acute renal insufficiency type. The differential diagnosis of legionnaires disease with mycoplasmal pneumonia, pneumococcal pneumonia and infiltrative pulmonary tuberculosis was also discussed. The first choice for treatment is erythromycin or erythromycin with rifampicin.