Abstract： Objective To investigate the cerebral protective effects of hyperoxia management during deep hypothermia circulatory arrest（DHCA） rabbit by the blood gas indexes, superoxide dismutase（ SOD） activity and malondialdehyde （MDA） levels of brain, and ratio of water to brain. Methods A DHCA and antegrade selective cerebral perfusion （ASCP） rabbit model was established. Twenty-four 11-13 week-old male New Zealand rabbits（ weighing 2.7 to 3.4 kg） were assigned to three groups with a random number table: a sham operation group （Sham group）, an ASCP group （S group）, and an ASCP ＋ hyperoxia management group （SH group）. There were eight rabbits in each group. We recorded the intraoperative values for arterial oxygen pressure （PaO2）, arterial oxygen saturation （SaO2）, jugular venous oxygen pressure（PjvO2）, jugular venous oxygen saturation（ SjvO2） and blood lactate level. The brain SOD activity, MDA levels, and ratio of water to brain were measured after the operation. Results Before initiating circulatory arrest, before initiating reperfusion and five minutes of reperfusion, levels of PaO2 , PjvO2 , and SjvO2 in the SH group were significantly higher than those of the S group and Sham group. SOD activity in the SH group was not significantly different from that of the S group[（213.53±33.52） U/mg. prot vs. （193.02±27.67） U/mg. prot] and Sham group[（213.53±33.52） U/mg. prot vs.（244.38±35.02）U/mg. prot], but the SOD activity in the S group was lower than that in the Sham group（ P ＜ 0.05）. MDA levels in the SH group were lower than that in the S group[（1.42±0.30） nmol/mg. prot vs. （2.37±0.55） nmol/mg. prot, P ＜ 0.05]. Conclusion Our data show that hyperoxia management during DHCA＋ASCP improves rabbits’PjvO2 and SjvO2, maintains brain SOD activity, and decreases brain MDA levels, demonstrating the neuroprotective effects of hyperoxia mangagement.
Objective To review the research progress of promoting the bone formation at early stage by components of the extracellular matrix (ECM). Methods Recent literature concerning the influence of these components on new bone formation and bone/implant contact was extensively reviewed and summarized. Results Coating of titanium or hydroxyapatite implants with organic components of the ECM (such as collagen type I, chondroitin sulfate, and Arg-Gly-Asp peptide) offers great potential to improve new bone formation and enhance bone/implant contact, which in turn will shorten recovery time and improve implant stability. Conclusion The increasing knowledge about the role of the ECM for recruitment, proliferation, differentiation of cells, and regeneration of tissue will eventually deal to the creating of an artificial ECM on the implant that could allow a defined adjustment of the required properties to support the healing process.
Sarcoidosis is a multi-organ inflammatory disorder characterized by the presence of non-caseating granulomas primarily affecting the lungs. The pathogenesis of sarcoidosis has not been fully clarified. In recent years, studies have suggested that a variety of pathogen infections, including Mycobacterium tuberculosis, Propionibacterium acnes, fungi, viruses, may be related to the occurrence and progression of sarcoidosis. This article reviews the researches on sarcoidosis and pathogen infection, aiming to explore the potential role of pathogen infection in the pathogenesis of sarcoidosis and provide another direction for the treatment of sarcoidosis.
Objective To investigate the correlation between glycosylated hemoglobin A1c (HbA1c) and severity of coronary artery lesions in young men with acute myocardial infarction (AMI). Methods Total 278 young men with AMI less than 45 years old were retrospectively studied, and all of them were admitted to hospital from January 2009 to December 2011, and had undergone coronary angiography. According to the results of coronary angiography, the patients were divided into three groups based on the number of artery lesions: the single group (156 cases), the double group (64 cases) and the triple group (58 cases). The relationship between the severity of coronary artery lesions and the following factors were observed: HbA1c, systolic blood pressure (SBP), diastolic blood pressure (DBP), hemoglobin (Hb), serum uric acid (UA), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), body mass index (BMI), smoking history, drinking history and family history of early coronary artery disease. Results a) HbA1c levels were gradually raised in all the three groups, but the single group (6.39±1.67%) was significantly lower than the double group (6.91±1.63%) and the triple group (7.41±2.12%), with significant differences (Plt;0.05); the HbA1c level of the single group was significantly lower than the triple group in both the ST-segment elevation AMI (6.42±1.68% vs. 7.17±1.86%, Plt;0.05) and the non-ST-segment AMI (5.57±0.37% vs. 8.56±2.83%, Plt;0.05); the HbA1c level of the single group was significantly lower than the triple group in patients with diabetes millitus (8.31±1.83% vs. 8.59±2.02%, Plt;0.05) and in patients without diabetes millitus (5.56±0.33% vs. 5.74±0.37%, Plt;0.05); b) There were significant differences in SBP, TC, HDL-C, LDL-C and drinking history between the single group and the other two groups (all Plt;0.05), and there were significant differences in DBP and TG between the single group and the double group (all Plt;0.05); and c) The results of logistic regression analysis showed that, LDL-C (OR=1.790), HbA1c (OR=1.287) and SBP (OR=1.042) were the independent risk factors (all Plt;0.05) for multiple lesions in coronary arteries of young men with AMI. Conclusion Glycosylated hemoglobin A1c is an independent risk factor for multiple lesions in coronary arteries of young men with AMI.
Objective To introduce a novel approach using parallel placement of another oxygenator in the recirculation line as oxygen supply for oxygenator failure without circulatory arrest in cardiopulmonary bypass （CPB），and confirm its outcomes in an animal experiment. Methods A traditional piglet CPB model was established. Oxygenator failure model was established by reducing fraction of inspired oxygen （FiO2） from 80% to 21% after aortic cross-clamp and cardiac arrest in CPB. Another oxygenator was then parallel placed in the recirculation line to supply 100% oxygen.Dynamic changes in partial pressure of oxygen （PaO2），mixed venous oxygen saturation （SvO2），arterial oxygen saturation（SaO2） and blood pH of blood samples from the arterial perfusion duct were monitored with different blood flow of400 ml/min，800 ml/min and 1 100 ml/min. Results When FiO2 was reduced to 21%，PaO2 decreased to 64-67 mm Hg（P＜0.001），SaO2 decreased significantly to 88%-90% （P＜0.001），SvO2 decreased to 69%-72% （P＜0.001），and blood pH decreased too，all indicating oxygenator failure. After parallel placement of another oxygenator in the recirculation line was performed，PaO2，SaO2 and SvO2 all significantly increased，as well as blood pH. When the blood flow in the recirculation line achieved 33% or above of overall arterial perfusion flow，clinical oxygen demand was generally satisfied. Conclusion Parallel placement of another oxygenator in the recirculation line may be utilized as a treatment strategy for oxygenator failure without circulatory arrest and changeover of failed oxygenator.
ObjectiveTo observe the morphological characteristic by implanting domestic porous tantalum in rabbit patellar tendon and to evaluate biocompatibility features so as to provide experimental basis for porous tantalum used as interface fixation between tendon and bone. MethodsA total of 48 adult New Zealand white rabbits, male or female, weighing 2.5-3.0 kg, were selected. Porous tantalum flake (5 mm×5 mm×2 mm) was implanted in the left patellar tendon (experimental group) and the same size porous titanium flake in the right patellar tendon (control group). The animals were sacrificed at 2, 4, 8, and 12 weeks after implantation, then the specimens were harvested for gross observation, HE staining, scanning electron microscope (SEM) observation, and hard slices observation. ResultsNo animal died after operation. Porous tantalum was bonded closely with host tendon and no inflammatory reaction was found. Loose and thick fibrous capsule was observed at the beginning and became density and thinner in the end by microscope, showing significant difference between different time points in 2 groups (P<0.05), but no significant difference was found between 2 groups at different time points (P>0.05). The SEM observation showed that fibrous tissue attached to the surface and inner walls of porous tantalum at early stage, and extended on the material to reach confluence at late period, but the experimental group was more than the control group. Hard slices observation showed that the collagen fibrils were seen on porous tantalum interface with host tendon, and blood vessels grew into the pores. The control group and the experimental group showed no significant difference. ConclusionThe domestic porous tantalum has good biocompatibility. Connection and integration can be established between tendon and porous tantalum, and therefore it could be used in reconstruction of tendon-bone fixation device.
ObjectiveThe antibacterial properties of porous medical implant materials were reviewed to provide guidance for further improvement of new medical implant materials.MethodsThe literature related to the antibacterial properties of porous medical implant materials in recent years was consulted, and the classification, characteristics and applications, and antibacterial methods of porous medical implant materials were reviewed.ResultsPorous medical implant materials can be classified according to surface pore size, preparation process, degree of degradation in vivo, and material source. It is widely used in the medical field due to its good biocompatibility and biomechanical properties. Nevertheless, the antibacterial properties of porous medical implant materials themselves are not obvious, and their antibacterial properties need to be improved through structural modification, overall modification, and coating modification.ConclusionAt present, coating modification as the mainstream modification method for improving the antibacterial properties of porous medical materials is still a research hotspot. The introduction of new antibacterial substances provides a new perspective for the development of new coated porous medical implant materials, so that the porous medical implant materials have a more reliable antibacterial effect while taking into account biocompatibility.