To explore the safety testing evaluation index of breast-feeding by hepatitis B-positive mothers / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To explore the safety testing evaluation index of breast-feeding by hepatitis B-positive mothers.</p><p><b>METHODS</b>HBV DNA from serum and breast milk of 252 hepatitis B-positive mothers were detected with the real-time quantitative PCR.</p><p><b>RESULTS</b>The total positive rate of HBV DNA in serum had no difference with that in breast milk in hepatitis B-positive mothers (P > 0.05). The positive rate of HBV DNA in serum and breast milk of positive HBeAg were significantly higher than that of hepatitis B-positive mothers with negative HBeAg (P < 0.01).</p><p><b>CONCLUSION</b>To detecte HBeAg and HBV DNA in serum and breast milk have important significance for guiding of breast feeding of hepatitis B-positive mothers.</p>

Biomechanical researches on tissue engineering bone constructed by deproteinated bone / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study biomechanical changes of newly formed bones 24 weeks after repairing large defects of long bones of goats using heterogeneous deproteinated bone (DPB) prepared by modified methods as an engineering scaffold.</p><p><b>METHODS</b>According to a fully randomized design, 18 goats were evenly divided into three groups: normal bone control group (Group A), autologous bone group (Group B) and experimental group (Group C). Each goat in Groups B and C were subjected to the periosteum and bone defect at middle-lower part of the right tibia (20% of the whole tibia in length), followed by autologous bone or DPB plus autologous MSCs + rhBMP2 implantation, respectively and semi-ring slot fixation; while goats in Group A did not perform osteotomy. At 24 weeks after surgery, biomechanical tests were carried out on the tibias.</p><p><b>RESULTS</b>At 24 weeks after surgery, the results of anti-compression test on tibias in three groups were recorded by a functional recorder presented as linear pressure-deformation curve. The shapes of the curves and their change tendency were similar among three groups. The ultimate pressure values were 10.74 MPa+/-1.23 MPa, 10.11 MPa+/-1.35 MPa and 10.22 MPa+/-1.32 MPa and fracture compression rates were 26.82%+/-0.87%, 27.17%+/-0.75% and 28.22%+/-1.12% in Groups A, B and C, respectively. Comparisons of anti-compression ultimate pressures and fracture compression rates among three groups demonstrated no significant difference (P(AB) equal to 0.415, P(BC) equal to 0.494). Three-point anti-bend test on tibias was recorded as load-deformation curves, and the shapes of the curves and their change tendency were similar among three groups. The ultimate pressure values of the anti-bend test were 481.52 N+/-12.45 N, 478.34 N+/-14.68 N and 475.62 N+/-13.41 N and the fracture bend rates were 2.62 mm+/-0.12 mm, 2.61 mm+/-0.15 mm and 2.81 mm+/-0.13 mm in Groups A, B and C, respectively. There was no significant difference between groups (P(AB) equal to 0.7, P(BC) equal to 0.448). The ultimate anti-torsion torque values were 6.55 Nm+/-0.25 Nm, 6.34 Nm+/-0.18 Nm and 6.42 Nm+/-0.21 Nm and fracture torsion rates were 29.51 degree+/-1.64degree, 28.88 degree+/-1.46 degree and 28.81 degree+/-1.33 degree in Groups A, B and C, respectively. There was no significant difference between groups (P(AB) equal to 0.123, P(BC) equal to 0.346).</p><p><b>CONCLUSIONS</b>The biomechanical characteristics of newly formed bones from heterogeneous DPB for repairing large segmental long bone defect are comparable to those of normal bones and autologous bones. DPB has the potential for clinical usage as bone graft material.</p>

Effect of experimentally created occlusal disorders on the expression of estrogen in rat condylar cartilage / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of experimentally created occlusal disorders (ECOD) on the expression of estrogen in rat condylar cartilage.</p><p><b>METHODS</b>The model of ECOD was created by moving right upper and left lower first molars anteriorly. The animals in ECOD were sacrificed at 2, 4, 6, 8 weeks later. In removed occlusal disorders group, the moved first molars were extracted at 6 weeks later, and the animals were sacrificed 2 weeks later. The expression of estrogen was detected by SABC technique of immunocytochemistry, and then was analyzed by the density of estrogen-positive chondrocytes.</p><p><b>RESULTS</b>1) Estrogen was abundant in mature layer and hypertrophic layer of rat mandibular condylar cartilage. 2) In control group, the expression of estrogen decreased gradually from 6-week-old to 16-week-old. 3) In both childhood and puberty rats, the expression of estrogen in experiment group was significantly higher at 2 weeks after treatment, while no difference was found at 4, 6, 8 weeks after treatment. However, the expression in removed occlusal disorder group was higher than that in control group and 8 weeks of ECOD group.</p><p><b>CONCLUSION</b>In rat condylar cartilage, the expression of estrogen de-creases with age. Induced by ECOD, the expression of estrogen increases in early stage of remodelling activity.</p>

Immunological study on the transplantation of an improved deproteinized heterogeneous bone scaffold material in tissue engineering / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To observe the immune response after the transplantation of a deproteinized heterogeneous bone scaffold and provides the theoretic reference for clinical practice.</p><p><b>METHODS</b>The fresh pig bone and deproteinized bone were transplanted respectively to establish BABL/C thigh muscle pouches model of male mice and take the samples for detection at 1, 2, 4, 6 weeks after operation. Lymphocyte stimulation index, subset analysis, serum specific antibody IgG, cytokine detection and topographic histologic reaction after implantation were investigated.</p><p><b>RESULTS</b>After the transplantation of deproteinized bone, lymphocyte stimulation index, CD(4)(+) and CD(8)(+) T-lymphocyte subsets, serum specific antibody IgG and cytokines in deproteinized bone group were significantly lower than those in fresh pig bone group at each time point (P<0.05). The histological examination found that in fresh bone group at each time point, a large quantity of inflammatory cells infiltrated in the surrounding of bone graft, and they were mainly lymphocytes, including macrophages and monocytes. In deproteinized bone group, there were few inflammatory cells infiltration around bone graft one week after operation. The lymphocytes were decreased as time went by. At 6 weeks, fibroblasts and fibrous tissue grew into the graft, and osteoclasts and osteoprogenitor cells appeared on the verge.</p><p><b>CONCLUSIONS</b>The established heterogeneous deproteinized bone has low immunogenicity and is a potentially ideal scaffold material for bone tissue engineering.</p>

Properties of deproteinized bone for reparation of big segmental defect in long bone / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To explore suitable scaffold material for big segmental long bone defect by studying the properties of the prepared deproteinized bone.</p><p><b>METHODS</b>Cancellated bone were made as 30 mm x mm x 3 mm bone blocks from inferior extremity of pig femur along bone trabecula. The deproteinized bone was prepared with an improved method. Their morphological features, components, cell compatibility, mechanical and immunological properties were investigated respectively.</p><p><b>RESULTS</b>Deproteinized bone maintained natural reticular pore system. The main organic material is collagen I and inorganic composition is hydroxyapatite. It has good mechanical properties, cell adhesion rate and histocompatibility.</p><p><b>CONCLUSION</b>This deproteinized bone can be applicable as scaffold for reparation of big segmental defect in long bone.</p>

Preparation and physicochemical properties of scaffold materials of heterogeneous deproteinized bone / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To prepare and observe the physicochemical properties of scaffold materials of heterogeneous deproteinized tissue-engineered bone.</p><p><b>METHODS</b>Deproteinized bone was made through a series of physicochemical treatments in pig ribs and analyzed with histological observation, scanning electron microscopy, infrared spectrum, X-ray diffraction and energy dispersive analysis, Kjeldahl determination and mechanics analysis.</p><p><b>RESULTS</b>Interstitial collagen fiber was positive and mucin was negative in deproteinized bone, but, both were positive in fresh bone. Deproteinized bone maintained natural pore network. Its pore size was 472.51 micromolar+/-7.02 micromolar and the porosity was 78.15%+/-6.45%. The results of infrared spectrum showed that collagen was present in deproteinized bone. Both fresh and deproteinized bone had curve of hydroxyapatite. The Ca/P ratios were 1.71+/-0.95 and 1.68+/-0.76 (P larger than 0.05), and the protein contents were 26.6%+/-2.23% and 19.1%+/-2.14% (P less than 0.05) in fresh and deproteinized bone, respectively. There was no significant difference of destruction load under compression and maximal destruction load between fresh and deproteinized bone (P larger than 0.05). The elastic modulus was higher in deproteinized bone than that in fresh bone (P less than 0.05).</p><p><b>CONCLUSIONS</b>Physicochemical properties and mechanic strength of deproteinized tissue-engineered bone meet the demands of ideal scaffold materials. But, its immunogenicity should be observed through further experiments for its clinical applications.</p>

Treatment of high-energy tibia plateau injury with half-ring external fixation combined with minimum internal fixation / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of less invasive surgical treatment for high-energy tibia plateau injury with half-ring external fixation combined with minimum internal fixation.</p><p><b>METHODS</b>From January, 2003 to May,2006, 16 cases of high-energy tibia plateau fracture were treated with half-ring external fixation combined with minimum internal fixation including 10 cases of type V and 6 cases of type VI according to Schatzker's classification. The average age of the patients was 42.4 years (range 25 to 50 years).</p><p><b>RESULTS</b>All patients were followed for an average of 16 months (range 5 to 27 months). All the fractures healed after an average time of 3.5 months. Two patients developed infections of the pin holes. According to the criteria of Rasmussen, excellent results were achieved in 10, good results in 4 cases, moderate in 2, and poor in none.</p><p><b>CONCLUSION</b>Half-ring external fixation combined with minimum internal fixation can be ideal for treatment of complex tibia plateau fracture.</p>

Cellular compatibility of improved scaffold material with deproteinized heterogeneous bone / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study cellular compatibility of improved scaffold material with deproteinized heterogeneous bone and provide experimental basis on choosing the scaffold material in bone tissue engineering.</p><p><b>METHODS</b>Bone marrow stromal cells (BMSC) were co-cultured with heterogeneous deproteinized bone in vitro. The contrast phase microscope, scanning electron microscope, MTT assay, flow cytometry were performed and the BGP content and ALP activities were detected in order to observe the cell growth, adhesion in the material, cell cycle and cell viability.</p><p><b>RESULTS</b>The scaffold material of deproteinized heterogeneous bone had no inhibitory effect on cellular proliferation, differentiation and secretion function of BMSCs.</p><p><b>CONCLUSIONS</b>The established heterogeneous deproteinized bone has good biocompatibility with BMSCs and is a potentially ideal scaffold material for bone tissue engineering.</p>

Histological comparison of fate of ligamentous insertion after reconstruction of anterior cruciate ligament: autograft vs allograft / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To analyze the histological results and the biological remodeling of ligamentous insertion after the reconstruction of anterior cruciate ligament (ACL) with autograft or allograft tendon.</p><p><b>METHODS</b>Extensor digitorum tendon was harvested from hind limb as graft material and transplanted to reconstruct the resected ACL in 12 mongrel dogs. Each free tendon end was secured by holding sutures and then the sutures were tied to the post screw at the femoral and tibial bony tunnel outlet after transplantation respectively. Autograft was randomly performed on one side of knee while allograft on the other side of knee. After transplantation, the histological analysis was undertaken at the 6th, 12th weeks and the 6th month using hematoxylin-eosin (HE) stain under light microscope.</p><p><b>RESULTS</b>The insertion structure of normal ACL typically consisted of four layers, i.e., dense connective tissue, fibrocartilage, mineralized fibrocartilage and bone. There was a distinct regular tidemark line between fibrocartilage and mineralized fibrocartilage. At the 6th week postoperatively, loose connective tissue presented in the interspace between graft and bony tunnel wall in both autograft and allograft groups. At the 12th week postoperatively, the collagenous fibers between autograft and tunnel wall became well organized and the four layers of insertion with discontinuous tidemark line were demonstrated indistinctly in autograft group but not in allograft group. At the 6th month postoperatively, both of a clear and continuous tidemark line and distinct four layers could be seen in autograft group. In allograft group, only a waved discontinuous tidemark line was shown and either the anatomic morphology or the maturity of insertion was inferior to that of autograft group.</p><p><b>CONCLUSIONS</b>At the 6th month postoperatively, although the ligament-cartilage insertion is primarily formed after ACL reconstruction with autograft or allograft tendon, the histological morphology and the maturation of insertion of autograft tendon are better than those of allograft group, which suggests that postoperative rehabilitation should be paid more attention and could be safer if little delayed during ACL reconstruction with allograft tendon.</p>

The biomechanics of point contact-dynamic compression plate and its effects on bone perfusion / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To compare the mechanical properties of point contact-dynamic compression plate (PC-DCP) and its effects on cortical bone perfusion with that of dynamic compression plates (DCP) in goat tibiae.</p><p><b>METHODS</b>Twenty pairs of matched fresh goat tibiae were used. A transverse fracture model was established. The fractures with a 3mm interspace between the fracture ends were subject to fixations with the DCPs and the PC-DCPs respectively, then the four-points bending tests and the torsion tests were conducted to compare the mechanical properties of the PC-DCP with that of DCP. Another 13 sexually mature goats underwent fixations with the DCPs and the PC-DCPs, respectively, at the mid-shafts of the intact bilateral tibiae. Ischemic zones were observed at four time points (1 day, 2, 6, and 12 weeks after operation) using disulphine blue staining technique.</p><p><b>RESULTS</b>There were no significant differences in mechanical properties, such as bend- and torsion-resistance, between the DCPs and the PC-DCPs. One day, 2, and 6 weeks after operation, on the side of DCP fixation, outer cortical bone ischemia under the plate persisted, and this condition did not reverse until 12 weeks after operation. However, on the side of PC-DCP fixation, cortical bone ischemia occurred only in the periphery of the screw holes and at the contact sites of the PC NUTs 1 day after operation, and it disappeared at 2 weeks after operation.</p><p><b>CONCLUSIONS</b>The PC-DCP has similar biomechanical properties of the DCP, but is less detrimental to local bone blood circulation than the conventional plates.</p>

Study of biological safety of scaffold material with heterologous deproteinized bone / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To evaluate the biological safety of manufactured heterologous deproteinized bone and to provide an experimental basis for clinical applications.</p><p><b>METHODS</b>Deproteinized bone (10 mm) and leaching liquor were made from pig ribs with a series of physical and chemical methods, then were evaluated through acute and subacute toxicity test, hemolysis test, pyrogen test, intracutaneous test, intramuscular implantation test and cytotoxity test.</p><p><b>RESULTS</b>No obvious toxicity, hemolysis, pyrogenic characteristics, skin irritation, inflammatory reaction after intramuscular implantation and cytotoxity were observed.</p><p><b>CONCLUSIONS</b>The heterologous deproteinized bone has good biological safety and meets all the demands of scaffold material for tissue engineering.</p>

Effects of Yiqi Jiangzhuo Decoction on transforming growth factor-beta1 mRNA expression in treating ventricular remodeling in mice with repetitive CVB3m infection caused viral myocarditis / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the effects of Yiqi Jiangzhuo Decoction (YJD) on transforming growth factor-beta1(TGF-beta1) mRNA expression in treating ventricular remodeling in viral myocarditis.</p><p><b>METHODS</b>After being established into chronic viral myocarditis model by 4 times repetitively infecting with gradient multiplicative CVB3m, 160 male mice were divided into the blank group, the model group, the TCM treated group and the Western medicine treated group. On the 10th, 30th and 60th day after the last time of infection, mice were killed to observe their pathological changes of myocardium with HE staining and to detect TGF-beta1 mRNA expression in myocardial tissue with semi-quantitative RT-PCR method.</p><p><b>RESULTS</b>Pathological changes of myocardium alleviated, and TGF-beta1 mRNA expression distribution area reduced significantly in the two treated groups, as compared with those in the model group (all P < 0.05).</p><p><b>CONCLUSION</b>YJD could inhibit the hyperplasia and reconstruction of ECM by down-regulating TGF-beta1 mRNA expression to improve cardiac pathological changes in myocarditis, so as to prevent the occurrence of ventricular remodeling and the conversion of disease to dilative cardiomyopathy.</p>

Expression and effect of Caspase-3 in neurons after tractive spinal cord injury in rats / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate Caspase-3 expression and its role in neuronal apoptosis.</p><p><b>METHODS</b>The T13-L2 spinal cord of rats was injured by traction after the amplitude of P1-N1 wave, monitored by a cortical somatosensory evoked potential (CSEP) monitor, decreased to seventy percent of that before operation. Then rats were killed in 6 h, 1 d, 4 d, 7 d, 14 d and 21 d respectively after operation. Flow cytometer terminal deoxynucleotldyl transferease-mediated biotinylated deoxynuridine triphosphate nick end labeling (TUNEL), Caspase-3 activity assay and immunohistochemical method were applied to investigate Caspase-3 expression in the spinal cord tissue and to study neuronal apoptosis in rats.</p><p><b>RESULTS</b>After spinal cord injury, apoptotic cells detected by flow cytometry and TUNEL-positive cells were significantly more, and positive immunohistochemical staining of Caspase-3 and Caspase-3 activity were significantly higher in Group injury than in Groups control and laminectomy, respectively (P > 0.05, P > 0.01). Similar trend of changes was noticed in apoptotic cells, TUNEL-positive cells and positive immunohistochemical staining of Caspase-3, all of which reached their respective peak 7 days after operation. Caspase-3 activity reached its peak, however, 4 days postoperatively.</p><p><b>CONCLUSIONS</b>Increased expression and activity of Caspase-3 protein in neurons after tractive spinal cord injury is the biochemical signal of early spinal cell apoptosis. It is of great significance for understanding the mechanism of spinal cord injury.</p>

Efficient isolation of chondrocytes from rabbit articular cartilage with three-step enzymatic digestion and observation of their biological characteristics during cultivation in vitro / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the effect of isolating the chondrocytes from articular cartilage with the method of three-step enzymatic digestion, and the biological characteristics of the isolated chondrocytes during cultivation in vitro in order to evaluate their biological activity.</p><p><b>METHODS</b>The method of three-step enzymatic digestion was designed that the articular cartilage was digested one by one with the 1 g/L trypsin and 1 g/L EDTA, 1 g/L hyaluronidase and 2 g/L collagenase I in the culture medium to isolate chondrocytes. The harvesting and viability rate of the primary chondrocytes were detected. During the passage cultivation in vitro, the changes of the chondrocytes shape and growth were observed, the changes of the collagen type I and II and aggrecan in the extracellular matrix were investigated and detected.</p><p><b>RESULTS</b>(1) The extracellular matrix of articular cartilage was completely dissolved by the three-step enzymatic digestion, and the chondrocytes were completely isolated from the solid matrix. The number of the harvested chondrocytes from every gram of wet cartilage was 50.3 x 10(6) on average, and their viability rate was 98.8% on average. (2) The primary and first passage chondrocytes had triangle or multi-angle shape, and became elliptic shape at the growing confluence with the positive immunohistochemical stain of collagen type II and the strong heterochromia to toluidine blue. The content of sulfate glycosaminoglycans (GAG) in the extracellular matrix of the primary passage cells was (92 +/- 10) microg/cm(2). The chondrocytes after the third passaging gradually became spindle shape with the negative stain of collagen type II and the weak heterochromia to toluidine blue. The content of sulfate GAG of the fourth passage cells was (48 +/- 12) microg/cm(2).</p><p><b>CONCLUSION</b>(1) The method of three-step enzymatic digestion can make the extracellular matrix of articular cartilage completely degraded, and has advantages in the high efficiency of harvesting primary chondrocytes, high cellular viability rate and simple manipulation. (2) The primary and first passage chondrocytes have fine biological activity, and the chondrocytes after the third passaging have lost their special biological activity.</p>

Effect of bionics pulsed electromagnetic fields on the biomechanical property of ovariectomized osteoporosis rats / 中国康复理论与实践

@#ObjectiveTo observe the effect of bionics pulsed electromagnetic fields (BEMF) on the biomechanical property of ovariectomized Wistar rats.MethodsForty 6 month old female Wistar rats were randomly divided into four different groups: ovariectomy group (group A), sham operation group (group B), BEMF+ovariectomized group (group C) and estrogen+ovariectomized group (group D). All rats were subjected to bilateral ovariectomy except group B. 8 weeks after operation, rats of group D were given estrogen 0.5 mg/kg/2 w. Rats of group C were exposed to BEMF, 1 h /d. Rats of group A and B were given nothing as control groups. All treatments was being kept for 10 weeks. After treatments finished, measuring the biomechanical property of femur and lumbar spine.ResultsThere were significant differences in the biomechanical property between group D and group A, and group C and group A (P<0.05).ConclusionBEMF can improve the biomechanical property of ovariectomized Wistar rats significantly and increase the capability of resisting fracture significantly.

Etiology, classification and clinical evaluation of partial-thickness tears of rotator cuff / 中华创伤杂志(英文版)

Since partial-thickness tears of the rotator cuff were described well by Codman in 1934, they have been extensively discussed in all kinds of literatures. Partial-thickness tears of the rotator cuff are now considered to play a more significant role than previously in inducing patients' disability. Partial-thickness cuff tears deserve more clinical attention. Both accurate diagnosis and proper surgical repair are very essential. The cognition of partial-thickness tears has been deepened in the last decades. In this paper we will review the etiology, classification and clinical evaluation of partial-thickness tears of the rotator cuff.

Biomechanical study on the suture strength of ligament in cruciate ligament reconstruction / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To test the suture strength on the tendon or ligament end and evaluate the stitch in the reconstruction of cruciate ligament and its clinical application.</p><p><b>METHODS</b>Twenty-four specimens of patellar tendon with free ends were divided into 3 groups: Group I (3 Krackow stitches), Group II (2 Krackow stitches) and Group III (2 Krackow stitches with the first stitch passing through the tendon tissue as a modified Krackow stitch). These 3 groups were further divided into 6 subgroups according to different suture materials, No 1 Ethilon or stainless steel wire (phi=0.4 mm). Tensile test was undertaken to find out the least stitches with efficient suture pattern.</p><p><b>RESULTS</b>Two Krackow locking stitches had stronger strength than 0.4 mm-diameter stainless steel wire. The fixation strength of 2 stitches with No 1 Ethilon was more than 80 N, superior to the failure strength of the material itself. The same strength was maintained if the first stitch was across the tendon tissue transversely. There was no statistically significant difference in the suture strength between 2 and 3 Krackow locking stitches.</p><p><b>CONCLUSIONS</b>The suture strength is greater than the failure strength of the suture material. Less suture exposure can be achieved when the first stitch is across the tendon tissue while maintaining a comparable strength to other sutures. To attain higher suture strength, stronger materials or multiple strands rather than more stitches are preferred. Therefore, a rapid early rehabilitation of range of motion (ROM) is possible and reliable in practice.</p>