关于龙瑞麟的一个公开问题

本文证明了增加凹函数的严格凹性与慢增性是等价的，从而解决了龙瑞麟[1、2]中的一个公开问题．

Treatment of chronic proliferative cholangitis with c-myc shRNA

AIM： To investigate the feasibility and effectiveness of c-myc shRNA in inhibiting the hyperplastic behavior and lithogenic potentiality of chronic proliferative cholangitis （CPC）, in order to prevent stone recurrence and biliary restenosis. METHODS： An animal model of CPC was established by giving intralumenally 0.5 mL of c-myc shRNA. Then, the effects of c-myc shRNA on hyperplastic behavior and lithogenic potentiality of CPC were evaluated by histological observation, immunohistochemistry, real- time PCR and Western blotting for c-myc, proliferating cell nuclear antigen （PCNA）, procollagen m, mucin 5AC, enzymatic histochemistry for 13-glucuronidase, and biochemistry for hydroxyproline in the diseased bile duct. RESULTS： Treatment with c-myc shRNA efficiently suppressed the hyperplasia of biliary epithelium, submucosal gland, and collagen fiber by inhibiting mRNA and protein expression of c-myc. More importantly, it decreased the lithogenic potentiality of CPC by inhibiting the expression of mucin 5AC and the secretion of endogenous 13-glucuronidase. Further investigation indicated that c-myc shRNA-3 had a better inhibitory effect on CPC. CONCLUSION： Treatment with c-myc shRNA-3 can control CPC and reduce the lithogenic potentiality of CPC.

MUC5AC EXPRESSION UP-REGULATION GOBLET CELL HYPERPLASIA IN THE AIRWAY OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Objective To determine the number of goblet cells, the change of MUC5AC expression in chronic obstructive pul- monary disease (COPD) patients and the relationship of smoking with goblet cell, MUC5AC, and lung function. Methods Eighteen patients undergoing lung resections for a solitary peripheral carcinoma were classified by lung function as having COPD. Twenty patients with normal lung function served as the control group. Normal lobe bronchioles far away from the lesion site were taken for paraffin section. Goblet cells were identified by AB/PAS staining and the ex- pression of MUC5AC in the paraffin’s section was tested by immunohistochemistry. Results Goblet cell hyperplasia was observed in the COPD group. The positive rate of goblet cell in COPD group (0.20% ± 0.10%) was significantly higher than that in the normal lung function group (0.13% ± 0.06%, P < 0.05). The posi- tive rate of MUC5AC expression in the COPD group (0.27% ± 0.09%) was higher than that in the normal lung function group (0.20% ± 0.10%, P < 0.05). The positive rate of goblet cell in smokers (27.93% ± 9.00%) of the COPD group and normal lung function group was higher than that in non-smokers (17.70% ± 9.37%, P < 0.05), while MUC5AC expression had no significant difference between smokers and non-smokers (17.88% ± 6.44% and 10.88% ± 7.10%, respectively). Conclusion For COPD patients with declined lung function, there were goblet cell hyperplasia and increased expres- sion of MUC5AC. MUC5AC expression up-regulation may due to goblet cell hyperplasia. Smoking may be an important factor for goblet cell hyperplasia.

Chronic bile duct hyperplasia is a chronic graft dysfunction following liver transplantation

AIM: To investigate pathological types and influential factors of chronic graft dysfunction (CGD) following liver transplantation (LT) in rats. METHODS: The whole experiment was divided into three groups: (1) Normal group (n = 12): normal BN rats without any drug or operation; (2) SGT group (syngeneic transplant of BN-BN, n = 12): both donors and recipients were BN rats; and (3) AGT group (allogeneic transplant of LEW-BN, n = 12): Donors were Lewis and recipients were BN rats. In the AGT group, all recipients were subcutaneously injected by Cyclosporin A after LT. Survival time was observed for 1 year. All the dying rats were sampled, biliary tract tissues were performed bacterial culture and liver tissues for histological study. Twenty-one d after LT, 8 rats were selected randomly in each group for sampling. Blood samples from caudal veins were collected for measurements of plasma endotoxin, cytokines and metabonomic analysis, and faeces were analyzed for intestinal microflora. RESULTS: During the surgery of LT, no complications of blood vessels or bile duct happened, and all rats in each group were still alive in the next 2 wk. The long term observation revealed that a total of 8 rats in the SGT and AGT groups died of hepatic graft diseases, 5 rats in which died of chronic bile duct hyperplasia. Compared to the SGT and normal groups, survival ratio of rats significantly decreased in the AGT group (aP < 0.01, bP < 0.001, respectively). Moreover, liver necrosis, liver infection, and severe chronic bile duct hyperplasia were observed in the AGT group by H and E stain. On 21 d after LT, compared with the normal group (25.38 ± 7.09 ng/L) and SGT group (33.12 ± 10.26 ng/L), plasma endotoxin in the AGT group was remarkably increased (142.86 ± 30.85 ng/L) (both P < 0.01). Plasma tumor necrosis factor-α and interleukin-6 were also significantly elevated in the AGT group (593.6 ± 171.67 pg/mL, 323.8 ± 68.30 pg/mL) vs the normal (225.5 ± 72.07 pg/mL, 114.6 ± 36.67 pg/mL) and SGT groups (321.3 ± 88.47 pg/mL, 205.2 ± 53.06 pg/mL) (P < 0.01). Furthermore, Bacterial cultures of bile duct tissues revealed that the rats close to death from the SGT and AGT groups were strongly positive, while those from the normal group were negative. The analysis of intestinal microflora was performed. Compared to the normal group (7.98 ± 0.92, 8.90 ± 1.44) and SGT group (8.51 ± 0.46, 9.43 ± 0.69), the numbers of Enterococcus and Enterobacteria in the AGT group (8.76 ± 1.93, 10.18 ± 1.64) were significantly increased (both aP < 0.01, bP < 0.05, respectively). Meanwhile, compared to the normal group (9.62 ± 1.60, 9.93 ± 1.10) and SGT group (8.95 ± 0.04, 9.02 ± 1.14), the numbers of Bifidobacterium and Lactobacillus in the AGT group (7.83 ± 0.72, 8.87± 0.13) were remarkably reduced (both aP < 0.01, bP < 0.05, respectively). In addition, metabonomics analysis showed that metabolic profiles of plasma in rats in the AGT group were severe deviated from the normal and SGT groups. CONCLUSION: Chronic bile duct hyperplasia is a pathological type of CGD following LT in rats. The mechanism of this kind of CGD is associated with the alterations of inflammation, intestinal barrier function and microflora as well as plasma metabolic profiles.

Proliferation in rat gastric mucosal cells induced by chronic ethanol feeding through the ROS/BMK1 pathway

Objective: To investigate the correlation between the gastric mucosal cell proliferation and low-concentration alcohol intake in a chronic drinking rat model, and to investigate the possible role of ROS/BMK1 pathway in this process. Methods: SD rats were randomly divided into 4 groups: control group, administered with tap water; ethanol group, with 6% ethanol in the drinking water; quercetin group, with quercetin (100 mg/kg) by intragastric gavage twice a day; ethanol+quercetin group, administered with quercetin combined with 6% ethanol. The cell proliferation in rat gastric mucosa was analyzed by flow cytometery and proliferating cell nuclear antigen (PCNA) immunohistochemical staining. Activation of ERKs and BMK1 was evaluated by the expression and phosphorylation of these kinases using Western Blot analysis. Results: Compared to the controls, the cell proliferation in gastric mucosa of rats exposed to the ethanol for 7 d was enhanced, and the activation of BMK1 was also increased in this period. Otherwise quercetin, as a free radical scavenger, attenuated increased cell proliferation and activation of BMK1 in rat stomach treated with ethanol. However, no changes of ERKs expression and phosphorylation occurred in the rats in all groups. Conclusion: These results suggested that the ROS and BMK1 activation may be a central mechanism, which underlies cell proliferation in rat gastric mucosa stimulus with the chronic low-concentration ethanol.

Depressant effect and mechanism of atorvastatin on the chronic rejection of aortic allograft in rats

Objective To investigate the depressant effect and mechanism of atorvastatin on the chronic rejection of aortic allograft in rats. Methods： The models of abdominal aorta transplantation were made with micro-surgery in rats. The recipients were divided into three groups： allograft control group, atorvastatin-treated group and isograft control group. Vascular intimal thickness in all of the groups were observed by histological examination. The expression of PCNA and α-SMA were determined by immunohistochemistry. The content of nitric oxide was determined by nitrate reductase chromatometry. Results： The vascular intimal thickness in rats of atorvastatin-treated group （11.60% ± 2.40% ） were lower than those in allograft control group （34.60 % ± 6.40 % ; P 〈 0.05） and higher than those in isograft control group （1.15 % ± 0.65 %; P〈 0.05 ）. The expression level of PCNA was decreased in atorvastatin-treated group （4.80% ± 0.80% ） than allograft control group （18.40% ± 1.80% ; P〈0.05） and higher than isograft group （1.20% ± 0.40% ; P〈0.05）. Conclusion： The expression of PCNA in the transplant aorta could be suppressed by atorvastatin, which resalted in relief of chronic rejection of aortic allograft.

Experimental evidence for non-linear growth in compressible mixing layer

An experimental study of compressible mixing layers(CMLs)was conducted using planar laser Mie scattering(PLMS)visualizations from condensed ethanol droplets in the flow.Large ensembles of digital images were collected for two flow conditions at convective Mach numbers Mc=0.11 and 0.47.The coherent vortices,braids and eruptions in the mixing zone were observed,interpreted as evidence of multi-scale,three-dimensional structures at a high Reynolds number.The mixing layers with a large visualized range present two stages along the streamwise direction,corresponding to the initial mixing and the well-developed stage.A new method,the gray level ensemble average method(GLEAM),by virtue of the similarity of the mixing layer,was applied to measure the growth rate of the CML thickness.New evidence for a nonlinear growth of CML is reported,providing an interpretation of previous observations of the scattering of the growth rate.