Seventeen cases involving 18 fingers of acute rupture of flexor tendon within the Zone Ⅱ were repaired by microsurgical technique for reconstructing the digital sheath with biological membrane since 1989. The excellent/good rate based on Eaton grading was 89%. The main procedure of the operation. the early postoperative rehabilitation and active excercises were described.
Between 1988 and 1994, 78 cases (183 tendons) of flexor tendon injuries of the hand were repaired by microsurgical techique. The patients were followed up from4 to 6 months. The results were assessed according to the grading method of TAM. In 36 cases, 78 tendons were repaired by microsurgical suture and the excellentgood rate reached 76.2 per cent and the other 42 cases, 105 tendons were repaired with biological memberane wrapped arround the anastomotic site following microsurgical suture, in which, 32 cases, 77 tendons were followed up and the excellentgood rate was 89.5 per cent. The curative effect between the two groups hadsignificant difference statistically (Plt;0.05). Those cases with a bad results were mainly those injuries occurred in Zone II which had very poor soft tissue condition of the palm and thoes old cases having extensive scar tissue formation surrounding the tendon bed.
Objective To observe the inhibitory characteristics of silver nanoparticles (AgNP) on bacterial biofilms and investigate their inhibitory effect on biofilm formation on three common orthopedic biomaterials. Methods The minimal inhibitory concentration (MIC) and minimal biofilm inhibitory concentration (MBIC) of AgNP were determined by microplate dilution assay. Biofilms of Staphylococcus aureus (ATCC 25923) were cultured on three orthopedic biomaterials (titanium alloy, titanium oxide, and stainless steel) and intervened with AgNP at concentrations of 32, 16, 8, 4, 2 and 0 μg/mL to determine the MBICs on the three materials. The effects of AgNP on biofilm formation were analyzed by scanning electron microscopy and measuring optical density. Results The MIC and MBIC of AgNP in the microplate assay were both 16 µg/mL. The MBICs of AgNP on biofilm formation in titanium oxide, titanium alloy, and stainless steel were 16 μg/mL, 32 μg/mL, and 32 μg/mL, respectively. Among the three materials, the lowest optical density was observed on titanium oxide, while the highest was on titanium alloy. Conclusions AgNP has strong antibacterial biofilm characteristics and can prevent the formation of Staphylococcus aureus biofilm in vitro. Biofilm formation is most pronounced on titanium alloy, least on titanium oxide, and intermediate on stainless steel.
ObjectiveTo establish an in vitro model of Candida albicans-Staphylococcus epidermidis mixed species biofilm on polyvinyl chloride (PVC) material, and to observe mixed species biofilm formation and its microstructure. MethodsStaphylococcus epidermidis bacteria (ATCC35984) and Candida albicans fungal (ATCC10231)were co-incubated with 0.5 cm diameter PVC pieces in tryptic soy broth (TSB) to form mixed specie biofilms (experimental group). At 2, 6, 12, 24, 48, and 72 hours, the thicknesses of the biofilms, the number of bacteria per sight, and the percentage of viable cells in biofilms were measured, and three-dimensional images of biofilms were obtained using confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM) at 48 hours. PVC material cultured in the TSB medium served as control group. ResultsIn control group, there was no pathogenic bacteria adhesion on the PVC material surface. In experimental group, CLSM showed that colonies and biofilm formation were found at 6 hours after co-culture, and gradually increased with time. The pathogenic bacteria colonies reached the peak at 24 hours, and biofilm thickness attained peak value at 48 hours. In experimental group, the number of colony was significantly different among 2, 6, and 24 hours, and between 2, 6 hours and 48, 72 hours (P<0.05), but no significant difference was found among 24, 48, and 72 hours (P>0.05). The biofilm thickness showed significant difference between the other time points (P<0.05) except between 48 and 72 hours (P>0.05). The percentage of viable cells in the outer layers of the biofilm was significantly higher than that in inner and middle layers at 48 hours (P<0.05). Three-dimensional reconstruction displayed that the surface of mixd species was uneven; living bacterium mainly located at the protuberance, and dead bacteria mainly located at the concaves. SEM image showed that Staphylococcus epidermidis attached to various forms of Candida albicans (spores, pseudohyphae, hyphae) gradually, and formed multilayer reticulate sophisticated structure on the surface of PVC with time. ConclusionCandida albicans-Staphylococcus epidermidis mixed species biofilm is sophisticated in structure. The combination of CLSM, SEM, and three-dimensional image reconstruction technology is ideal for investigation of mixed species biofilm on PVC material.
Objective To summarize the effect of biofilm (BF) on the occurrence of prosthetic joint infection (PJI). Methods The domestic and abroad original l iterature in recent years about the relationship between BF and PJI was reviewed. Results Infection is a critical compl ication for prosthetic joint replacement. Basic research showes one of the reasons for PJI is BF. After adherence of the bacteria to the surface of prosthetic joint, BF forms through a series of regulation andcontrol system. And it lead to the occurrence of PJI. Recently a lot of progress have been made in the research fields of BF related PJI, which have covered aetiology, diagnosis, treatment, and prevention. Different studies show that BF has close relationship with PJI. Conclusion BF is proved to have close relationship with PJI. It is important on cl inical significances to diagnose, treat, and prevent PJI.
Objective To investigate the effect of aureolysin （Aur） on staphylococcus aureus biofilm formation of dacron biomaterial surfaces under different Aur concentration. Methods Ninety dacron biomaterials were divided into 3 groups （group A, group IA, control group） with random number table （30 piece in each group）. Dacron biomaterials were put into vials contained staphylococcus aureus （105 CFU/ml） respectively; then Aur was added to make the concentration at 400ng/ml in group A, and group B at 80ng/ml. The thickness and number of staphylococcus aureus biofilm on the surfaces of dacron biomaterials of each group were evaluated by confocal laser microscopy and scanning electron microscopy after incubating 6h, 16h, 24h, 30h, and 48h. Results The thickness and number of staphylococcus aureus biofilm on dacron biomaterials surfaces increased significantly with time dependence in control group. The thickness and number of staphylococcus aureus biofilm in group A were less than those in group B and control group at each time points （P〈0. 05）. The thickness and number in group B were significantly decreased than those in control group （P 〈 0. 05）. Conclusion The study shows that Aur can effectively inhibit the formation of staphylococcus aureus biofilm on dacron biomaterials surfaces with dose dependence.
ObjectiveTo observe the bladder regeneration by collagen membrane scaffolds for bladder construction to find a new alternative scaffold material. MethodsTwelve healthy adult male Sprague Dawley rats, weighing 300-350 g, were randomly divided into collagen membrane scaffold group (experimental group, n=6), and sham operated group (control group, n=6). Upper hemicystectomy was performed and collagen scaffold was used for reconstruction in experimental group, while the bladder was turned over without bladder resection in control group. At 30 days after operation, the animals were sacrificed and grafts were harvested;HE staining and Masson staining were used to evaluate the bladder regeneration, immunohistochemical staining was performed with α-smooth muscleactin (α-SMA) and von Willebrand factor (vWF) markers to evaluate the percentage of α-SMA positive area and capillary number. ResultsThe rats of 2 groups survived to the end of the experiment, and no urine leakage or infection was observed in experimental group. Histologically, control group presented a pattern of normal bladder structure, experimental group presented a pattern of almost normal urothelium with a small amount of smooth muscle cells and a thin layer of undegraded collagen fibers. Immunohistochemically, experimental group showed ingrowth of smooth muscle fibers and new capillary formation along the collagen membrane scaffolds. The percentage of α-SMA positive area and capillary number in experimental group were significantly lower than those in control group (6.49%±2.14% vs. 52.42%±1.78% and 4.83±0.75 vs. 14.83±1.17, respectively)(t=40.40, P=0.00; t=17.62, P=0.00). ConclusionThe collagen membrane scaffolds could be an effective scaffold material for bladder reconstruction.
ObjectiveTo explore the function of intercellular adhesion A (icaA), fibrinogen binding protein (fbe), and accumulation-associated protein (aap) genes in formation of Staphylococcus epidermidis-Candida albicans mixed species biofilms. MethodsThe experiment was divided into 3 groups:single culture of Staphylococcus epidermidis ATCC35984 (S. epidermidis group) or Candida albicans ATCC10231 (C. albicans group), and co-culture of two strains (mixed group) to build in vitro biofilm model. Biofilm mass was detected by crystal violet semi-quantitative adherence assay at 2, 4, 6, 8, 12, 24, 48, and 72 hours after incubation. XTT assay was performed to determine the growth kinetics in the same time. Scanning electron microscopy (SEM) was used to observe the ultrastructure of the biofilms after 24 and 72 hours of incubation. The expressions of icaA, fbe, and aap genes were analyzed by real-time fluorescent quantitative PCR. ResultsCrystal violet semi-quantitative adherence assay showed that the biofilms thickened at 12 hours in the S. epidermidis and mixed groups; after co-cultured for 72 hours the thickness of biofilm in mixed group was more than that in the S. epidermidis group, and there was significant difference between 2 groups at the other time (P<0.05) except at 72 hours (P>0.05). In C. albicans group, the biofilm started to grow at 12 hours of cultivation, but the thickness of the biofilm was significantly lower than that in the mixed group in all the time points (P<0.05). XTT assay showed that the overall growth speed in the mixed group was greater than that in the C. albicans group, and it was greater than that in the S. epidermidis group at 48 hours; there was no significant difference in the growth speed between the mixed groups and the S. epidermidis group in the other time points (P>0.05) except at 12 hours (P<0.05). The absorbance (A) value in the mixed group was lower than that in the S. epidermidis group at 2 and 4 hours, but no significant difference was shown (P>0.05); the A value of mixed group was significantly higher than that of the C. albicans group after 6 hours (P<0.05). SEM observation showed that mature biofilms with complex structure formed in all groups. The real-time fluorescent quantitative PCR showed the expressions of fbe, icaA, and aap genes in mixed group increased 1.93, 1.52, and 1.46 times respectively at 72 hours compared with the S. epidermidis group (P<0.05). ConclusionMixed species biofilms have more complex structure and are thicker than single species biofilms of Staphylococcus epidermidis or Candida albicans, which is related to increased expressions of the icaA, fbe, and aap genes of Staphylococcus epidermidis.
Bacterial biofilm is the key problem of chronic wound infection and difficult healing. How to prevent and control bacterial biofilm and improve the prognosis of chronic wound has become a research hotspot in the field of wound care. This paper will summarize from the following aspects: four major stages in the process of chronic wound bacteria biofilm formation (surface adhesion, formation of small colonies, biofilm maturation, and dispersion and separation); characteristics of host immune response in the presence of biofilms; morphological, microbiological, and molecular detection methods for biofilms; and progress in in vitro trials, animal trials, clinical trials, and new therapeutic methods of biofilm. The purpose of this review is to provide evidence for the treatment of biofilms for chronic wounds.
Liposomes with precisely controlled composition are usually used as membrane model systems to investigate the fundamental interactions of membrane components under well-defined conditions. Hydration method is the most common method for liposome formation which is found to be influenced by composition of the medium. In this paper, the effects of small alcohol (ethanol) on the hydration of lipid molecules and the formation of liposomes were investigated, as well as its coexistence with sodium chloride. It was found that ethanol showed the opposite effect to that of sodium chloride on the hydration of lipid molecules and the formation of liposomes. The presence of ethanol promoted the formation of liposomes within a certain range of ethanol content, but that of sodium chloride suppressed the liposome formation. By investigating the fluorescence intensity and continuity of the swelled membranes as a function of contents of ethanol and sodium chloride, it was found that sodium chloride and ethanol showed the additive effect on the hydration of lipid molecules when they coexisted in the medium. The results may provide some reference for the efficient preparation of liposomes.