BACKGROUND:It is particularly important to establish an ideal animal model of pulmonary fibrosis to investigate the underlying pathogenesis and screen effective drugs to prevent and control pulmonary fibrosis. OBJECTIVE: To establish a modified scheme of establishing mouse models that can reflect pulmonary fibrosis formation in humans. METHODS: Fifty-six male C57BL/6 mice were randomly divided into two groups: A (a single large-dose injection) and B (multiple smal-dose injections). Mice in group A were subjected to a single intravenous injection of bleomycin 200 mg/kgviathe tail vein; and mice in group B received intravenous injections of bleomycin 50 mg/kg via the tail vein per week, totaly for 6 weeks. 

Objective To investigate the ultrasonographic and pathological changes of peripheral pulmonary lesions in acquired immunodeficiency syndrome (AIDS) complicated with Penicillium marneffei pneumonia (PMP) and their clinical significance.Methods The ultrasonographic and pathological data of peripheral pulmonary lesions in 31 cases of AIDS complicated with PMP who were diagnosed in Fourth People's Hospital of Nanning were retrospectively reviewed.Results Among 31 cases of PMP,20 cases (64.5％) showed star-like diffuse sonogram,7 cases (22.6％) low solid echo and 4 cases (12.9 ％) black hole-like sonogram in ultrasonographic changes of peripheral pulmonary lesions.In pathological examination,Penicillium marneffei were seen in all samples:periodic acid-Schiff stain (PAS) and periodic acid-Schiff diastase stain (PAS-D) were all positive.Twenty four cases (77.4％) mainly showed infiltration of inflammatory cells,and 7 cases (22.6 ％) mainly showed necrosis and fibrous hyperplasia.Among 20 patients with star like diffuse sonogram,19 were mainly infiltration of inflammatory cells in pathological changes,and 19 were CD4+ T lymphocyte counts of 100-200/μL.Among 4 patients with black hole-like sonogram,all were necrosis in the central and hyperplasia in the peripheral in pathological changes,and CD4-T lymohocyte counts were all＜50/μL.Conclusions In AIDS patients complicated with PMP,ultrasonographic features were probably correlated with pathological changes in biopsy tissues and CD4-T lymphocyte counts.

Objective To investigate and compare the clinical values of serum procalcitonin (PCT)and high sensitivity C-reac-tive protein (hs-CRP)levels for predicting the blood culture positivity in the patients with sepsis.Methods 132 adult patients with sepsis were enrolled in this study.Blood cultures were performed before the antibacterial therapy.The white blood cell (WBC) count,absolute neutrophil count(ANC),levels of PCT and hs-CRP were determined.The application value of PCT and hs-CRP for predicting the positive blood culture results were evaluated.Results The median serum PCT levels in the blood culture positive group and the blood culture negative group were 7.92 ng/mL and 0.95 ng/mL respectively,the difference had statistical signifi-cance(P <0.01).The receiver operating characteristic (ROC)curves showed that PCT had a higher predictive accuracy for blood culture positivity compared with hs-CRP,the area under the curve (AUC)was 0.810(P =0.001)and 0.690(P =0.274),respec-tively.The combined detection of PCT and hs-CRP for predicting the blood culture positive results was similar to the performance of PCT alone,AUC as 0.885 (P =0.001 ).The median cut point of PCT was 0.91 ng/mL,the sensitivity of PCT for predicting blood culture positivity was 90%.This sensitivity remained unchanged when PCT cut point was1.14ng/mL.Using the PCT cut points of 0.91 and 1.14 enabled reducing the submitted blood cultures by 51% and 56% respectively.Conclusion Compared with hs-CRP,serum PCT level could better predict the blood culture positivity in the patients with sepsis.

BACKGROUND:There is no effective drug for idiopathic pulmonary fibrosis (IPF), because of a lack of the animal model imitating the complete pathogenesis of human IPF. Therefore, it is critical to establish an ideal animal IPF model used for investigating the underlying pathogenesis and developing a kind of effective drug. OBJECTIVE:To establish an animal model that can mimic more characters of human IPF. METHODS:Seventy male C57BL/6 mice were randomly divided into two groups, fol owed by subjected to the intraperitoneal injection of bleomycin (35 mg/kg) on days 1, 4, 8, 11, 15, 18, 22, and 25, twice (group A) or once (group B) a week. Mice were sacrificed at 2, 4, 6, 8, and 10 weeks after the eighth injection, and the lung tissues were moved used for hematoxylin-eosin, Masson and immunohistochemical stainings. RESULTS AND CONCLUSION:There were various degrees of alveolitis and pulmonary fibrosis in the two groups at different time points after the last injection. The scores of alveolitis and pulmonary fibrosis in the group A began to gradual y increase from the 2nd week and reached the highest level at the 6th-8th weeks until the 10th week. In contrast, the scores of alveolitis and pulmonary fibrosis in the group B peaked at the 2nd week, then fluctuately decreased, and were significantly lower than those in the group A at the 6th week (P<0.05). Immunohistochemistry showed that type I col agen deposition was mainly distributed in the subpleural region, peri-vascular region and alveolar septa, which was consistent with Masson staining findings. The expression levels of transforming growth factorβ1 (TGF-β1) andα-smooth muscle actin (α-SMA) in the regions developing alveolitis and pulmonary fibrosis were significantly increased. In the group A, the expression levels of type I col agen, TGF-β1,α-SMA, and the hydroxyproline content in the lung tissues reached the peak level at 6-8 weeks. However, in the group B, al above indicators reached the highest level at the 2nd week, but gradual y decreased thereafter. At the 4th week, the expression Levels of TGF-β1 andα-SMA in the group B were significantly lower than those in the group A (P<0.05). At the 6th week, the hydroxyproline and type I col agen levels in the group B were significantly lower than those in the group A (P<0.05). In conclusion, the mouse model of pulmonary fibrosis induced by intraperitoneal injection of 35 mg/kg bleomycin twice weekly can be used to mimic the repetitive wound healing process, pathological morphology and cytokine changes of human IPF, which is prone to administration, with better stability and repeatability. This model is of great significance for the study on IPF. Subject headings:Disease Models, Animal;Pulmonary Fibrosis;Bleomycin