Antibacterial effect of low-temperature plasma on Enterococcus faecalis in dentinal tubules in vitro / 北京大学学报(医学版)

OBJECTIVE@#To construct a model of Enterococcus faecalis (E. faecalis) infection in dentinal tubules by gradient centrifugation and to evaluate the antibacterial effect of low-temperature plasma on E. faecalis in dentinal tubules.@*METHODS@#Standard dentin blocks of 4 mm×4 mm×2 mm size were prepared from single root canal isolated teeth without caries, placed in the E. faecalis bacterial solution, centrifuged in gradient and incubated for 24 h to establish the model of dentinal tubule infection with E. faecalis. The twenty dentin blocks of were divided into five groups, low-temperature plasma jet treatment for 0, 5 and 10 min, calcium hydroxide paste sealing for 7 d and 2% chlorhexidine gel sealing for 7 d. Scanning electron microscopy and confocal laser scanning microscope were used to assess the infection in the dentinal tubules and the antibacterial effect of low-temperature plasma.@*RESULTS@#The results of scanning electron microscopy and confocal laser scanning microscopy showed that after 24 h of incubation by gradient centrifugation, E. faecalis could fully enter the dentinal tubules to a depth of more than 600μm indicating that this method was time-saving and efficient and could successfully construct a model of E. faecalis infection in dentinal tubules. Low-temperature plasma could enter the dentinal tubules and play a role, the structure of E. faecalis was still intact after 5 min of low-temperature plasma treatment, with no obvious damage, and after 10 min of low-temperature plasma treatment, the surface morphology of E. faecalis was crumpled and deformed, the cell wall was seriously collapsed, and the normal physiological morphology was damaged indicating that the majority of E. faecalis was killed in the dentinal tubules. The antibacterial effect of low-temperature plasma treatment for 10 min exceeded that of the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d. These two chemicals had difficulty entering deep into the dentinal tubules, and therefore only had a few of antibacterial effect on the bacterial biofilm on the root canal wall, and there was also no significant damage to the E. faecalis bacterial structure.@*CONCLUSION@#Gradient centrifugation could establish the model of E. faecalis dentin infection successfully. Low-temperature plasma treatment for 10 min could kill E. faecalis in dentinal tubules effectively, which is superior to the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d.

Clinical analysis of two different incisions of coaxial phacoemulsification / 国际眼科杂志(Guoji Yanke Zazhi)

·AIM: To compare the clinical effects of 2.2mm coaxial micro-incision and 3.0mm standard incision in cataract phacoemulsification surgery. ·METHODS: A total of 67 patients (80 eyes) were randomly divided into two groups. Cataract phacoemulsification and artificial lens implantation surgery was carried out with 2. 2mm coaxial micro -incision (Group A, 40 eyes) and 3. 0 mm standard incision(Group B, 40 eyes), respectively. The effective phacoemulsification time and average ultrasound energy, corneal endothelial cell count, corneal edema, corneal astigmatism, postoperative visual acuity and postoperative complications were compared between the two groups. ·RESULTS: Effective phacoemulsification time of Group A and Group B was 8. 18 ± 11. 22s and 7. 82 ± 2. 12s, respectively, and the difference had no statistical significance(P> 0. 05); average ultrasonic energy was (17.25 ± 4.22)% and (17.64 ± 4.27)%, respectively, and the difference was not statistical significance(P>0.05). There was no significant difference in endothelial cells between the two groups of corneal endothelial cells at 1wk after surgery compared with that before operation (P>0.05). On the first day after surgery, corneal edema was observed in some patients. There were 9 eyes in Group A,6 eyes in Group B,corneal edema relief or subsidence after 3d to 5d. There was significant difference in corneal astigmatism change between the two groups at 1wk (P<0.05), but there was no significant difference at 1 and 3mo after operation (P>0.05). The changes of corneal astigmatism before and after operation in Group A were insignificant (P>0. 05), while the changes of corneal astigmatism before and after operation in Group B were significantly different (P< 0. 05). At 1 and 3mo after operation, the astigmatism of each group tended to be stable, and the corneal astigmatism in the two groups after 1 and 3mo had no statistical significant difference (P> 0. 05). The uncorrected visual acuity (UCVA) differences of the two groups was statistically significant at 1d,1wk and 1mo after operation (P<0.05), but there was no significant difference between the two groups in UCVA after 3mo (P>0.05). ·CONCLUSION: For soft or medium - hard nucleus cataract, compared with the traditional 3. 0mm small-incision coaxial phacoemulsification, the 2.2mm micro-incision coaxial phacoemulsification can effectively reduce the surgically induced astigmatism, and the astigmatism state is relatively stable, and conducive to early recovery of visual acuity.

Effect of 17β-estradiol on renal tubular cells apoptosis and inflammation induced by renal ischemia /reperfusion injury in rats / 临床与实验病理学杂志

Purpose To investigate the effects and mechanism of 17β-estradiol on the apoptosis and inflammation of renal tubular cells in rats with renal ischemia/reperfusion injury. Methods All the female Sprague-Dawley rats were ovariectomized and randomly divided into four groups: Control group, Sham group, I/R group and estrogen plus I/R (E2 + I/R) group (n = 8). Right kidney of the rat was excised and artery of the left kidney was blockaded for 45 min.24 h after the reperfusion, we collected the blood and nephridial tissue of each group. An automatic biochemical analyzer was used to measure the expression level of BUN and Cr in blood. Hematoxylin-eosin (HE) staining was used to observe the pathological changes and the degree of inflammatory reaction of the ischemia/reperfusion injury kidney. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) method was used to detect the apoptosis of renal tubular cells. The expression levels of Cleaved-Caspase-3 protein were measured by Western blot, while the numbers of CD4+ T lymphocyte infiltration in each group were tested by immunofluorescence (IF). Results Compared with the Sham group, expression level of BUN, Cr and Cleaved-Caspase-3 in I/R group significantly increased (P＜0.05) as well as the number of apoptotic cells (P＜0.05). In the meantime, inflammatory reaction significantly aggravated (P＜0.05) and the number of CD4 + T lymphocytes increased remarkably (P＜0.05). However, expression level of BUN, Cr and Gleaved-Caspase-3 in E2 + I/R group decreased significantly (P＜0.05) and the pathological damage in the kidney was alleviated (P＜0.05) compared with I/R group, furthermore, the number of apoptotic cells decreased (P＜0.05) compared with I/R group. The inflammatory reaction significantly blunted (P＜0.05) and the infiltration of CD4 + T lymphocytes decreased remarkably (P＜0.05) compared with I/R group. Conclusion Estrogen can inhibit the expression of Cleaved-Caspase-3 in renal tissue during ischemia/reperfusion injury and reduce the apoptosis of renal tubular cells. It can also reduce the infiltration of CD4 + T lymphocytes, thus playing a protective role on renal ischemia/reperfusion injury.

Staining effect of bovine incisors in vitro by tea solutions / 北京大学学报(医学版)

OBJECTIVE@#To determine the optimum staining condition of tea solutions on bovine incisors in vitro, by comparing the color stability of tooth surface of different concentrations of tea solutions and methods on bovine incisors in vitro.@*METHODS@#Twenty bovine incisors with color surface A1 were chosen, then randomly divided into 4 groups (n=10). Group 1: soaked with 2% tea solution continuously for 6 days; group 2: soaked with 2% tea solution for 6 days, but changed fresh tea solution everyday; group 3: soaked with 1% tea solution continuously for 6 days; group 4: soaked with 1% tea solution for 6 days but fresh tea solution changed every day. After 6 days of staining, the surface color (Δ E value) of all the samples were measured with crystal eye. After brushing 30 times with toothbrushes, the color of bovine incisors were measured again. Then the samples were soaked in artificial saliva at 37 ° C, and Δ E value was measured for 14 days.@*RESULTS@#After staining for 6 days, the Δ E values of the 2% tea solution groups were better than those of the 1% groups (20.21 vs. 16.44, 24.09 vs. 19.22, P<0.05); the groups with the same tea solution concentration, a better result was observed for the group soaked with daily fresh tea solution than for the group that experienced continuous staining (24.09 vs. 20.21, 19.22 vs. 16.44, P<0.05). Groups 1 and 2 were selected for subsequent brushing experiments. The color of both groups became lighter after brushing, and a better result was observed for the continuous staining group than for the group stained in daily fresh solution (3.06 vs. 9.51, P<0.05). The samples with better coloring effect soaked with 2% tea solution continuously for 6 days were put into artificial saliva for 14 days. There was not any significant change in coloring at the end of the first two days (1.51 vs. 1.51, P>0.05), and the color was visibly lighter after the third day (1.51 vs. 5.89, P<0.05), and no further significant change was observed until the 14th day (5.81 vs.5.89, P>0.05), which was darker coloring than that of the pre-staining group.@*CONCLUSION@#Continuous staining on bovine incisors with 2% tea solution with subsequent soaking in artificial saliva resulted in consistent coloring from day 3 to day 14, and this method could be used as an ideal model for teeth staining in vitro.

Expression of occludin in corneal epithelium after flap-free epipolis laser in-situ keratomileusis and laser-assisted subepithelial keratectomy / 中华实验眼科杂志

Background Tight junctions are thought to play a significant role in the maintenance of the corneal epithelial defense for the eye,and the restoration of the tight junctions is critical during epithelial wound healing after refractive surgery.However,there are few reports about this study. Objective The aim of this study was to investigate and compare the expression of occludin in corneal epithelium following flap-free epipolis laser insitu keratomileusis (Epi-LASIK) and laser-assisted subepithelial keratectomy ( LASEK ). Methods Forty-eight clean New Zealand white rabbits were randomized into 2 groups,and 24 rabbits for each group.Flap-free Epi-LASIK and LASEK were performed in the right eyes of the rabbits in two groups,and other 2 age matched normal rabbits were as normal controls.The animals were sacrificed and the corneal samples were obtained at 1,2,3,5 days after surgery.Immunofluorescence staining was used to detect the expression of occludin in the corneal epithelium,and RT-PCR was used to identify the level of occludin mRNA in the central cornea. Results Occludin protein was expressed innormal corneal epithelium and showed the green fluorescence with the regular arrangement.The fluorescence intensity was lower in 1 -2 days in LASEK group with the irregular arrangement;while the fluorescence signal in corneal epithelium was stronger in flap-free Epi-LASIK group.3-5 days after surgery,the fluorescence intensities were bothenhanced in two groups.RT-PCR showed that the relative expression of occludin mRNA in corneal epithelium was 0.11 ±0.02,0.25 ± 0.03,0.43 ± 0.04 in LASEK group 1,2,3 days after surgery,respectively,and was lower than those of flap-free Epi-LASIK group ( 0.20± 0.04,0.44 ± 0.04,0.76 ± 0.04 ),showing significant differences between these two groups ( t =6.476,12.898,17.315,P＜ 0.05 ).No significant difference was seen in the expression of occludin mRNA in 5 days after surgery between two groups( t=-0.733,P＞0.05).The relative values of occludin mRNA expression in corneal epithelium were gradually increased with time prolongation,presenting a significant difference among various time points ( Ftime =768.903,P =0.000). Conclusions The reformation of occludin in flap-free Epi-LASIK group is faster than that in LASEK group.Therefore,flap-free Epi-LASIK is prominant in reducing the stimulated symptoms and complication after the surgery.

Primary non-Hodgkin's lymphoma of the testis and penis: clinical analysis of 5 cases / 中华男科学杂志

<p><b>OBJECTIVE</b>To improve the clinical diagnosis and treatment of primary non-Hodgkin's lymphoma of male genitalia.</p><p><b>METHODS</b>We retrospectively reviewed the clinical data of 5 cases of primary non-Hodgkin's lymphoma of male genitalia, 4 in the testis and 1 in the penis, we also analyzed the relevant literature and clinical significance of the disease.</p><p><b>RESULTS</b>All the 5 cases were treated by surgery and pathologically confirmed to be non-Hodgkin's lymphoma. Three of them received chemotherapy, and the other 2 (1 in the testis and 1 in the penis) underwent both chemotherapy and radiotherapy after the operation. Follow-up averaged 25 months, during which 1 of the patients died and the other 4 survived.</p><p><b>CONCLUSION</b>Primary non-Hodgkin's lymphoma of male genitalia is an uncommon disease with atypical clinical presentations and poor prognosis, which occurs mostly in elderly males. Definite diagnosis of the disease mainly depends on histopathology and immunohistochemistry. Surgery with multiagent chemotherapy and radiotherapy is advisable for its treatment.</p>