OBJECTIVE: To establish the animal models of mandibular distraction osteogenesis in rabbits and study its osteogenetic mechanism. METHODS: The right mandibles just anterior to the first molars of 12 rabbits were performed osteotomies, and the mandibles were positioned with distractors. The left mandibles were control group without operation. After 1 week, the distractors were stretched 0.9 mm every day for 10 days progressively. One day, 2, 4, 8 weeks after distraction, the mandibles were studied with gross measurement, X-ray, and histological examination. RESULTS: The right mandible were lengthened 8.3 mm on average without bone nonunion and deformity healing. It was observed that the gaps between the distracted bone edges were first occupied by fibrous tissue. Two weeks after distraction, it was found that the gaps were bridged by callus in X-ray, the new bone and the normal bone could not be differentiated clearly after 8 weeks. In histological sections, there were collagen bundles in early distraction, then those collagen bundles were calcificated and become trabeculaes. No Cartilage was found during distraction. CONCLUSION: It suggests that the rabbit mandible can be lengthened by distraction osteogenesis, and the new bone is formed by intramembranous ossification.
Objective To investigate the effect of the morphological changes in the proximal femur on the prothesis selection in the total hip arthroplasty in the patients with ankylosing spondylitis. Methods The experimental group was composed of 13 patients (16 hips) with ankylosing spondylitis, which was treated with the total hip arthroplasty, and the control group was composed of 16 patients（19 hips）with non-ankylosing spondylitis，which was also treated with the total hip arthroplasty. In the two groups, the measurements of Singh index，canal flare index，morphological index of the cortex and cortical index were performed in the two groups. Results The results of the statistical analysis on Singh index，canal flare index, morphological index of the cortex and cortical index in the experimental group were 3.81±0.54, 2.63±0.41, 2.02±0.38 and 1.69±0.69, respectively, but 4.63±0.62, 3.03±0.27, 2.76±0.28 and 2.12±0.24, respectively in the control group. Therewas a significant difference in Singh index, canal flare index, and morphological index of the cortex between the two groups (Plt;0.05)，while there was no statistical difference in cortical index between the two groups (P＞0.05). The patientswith ankylosing spondylitis had more serious osteoporosis in their proximal femur. Conclusion Cemented femoral prosthesis should be used in the total hip replacement in patients with ankylosing spondylitis, and the revision total hip arthroplasty should be performed on patients with more serious osteoporosis.
In order to study the influence of severity of tendon injury on the morphology of collagen fibers during healing process of extensor tendons, 40 female Wistal rats were used for investigation. The rats were divided into 2 groups. Transection of the tendon of extensor digitorum longus was performed in one group, while partial section of the same tendon was performed in the other group. Morphometric analysis was undertaken on the 15th, 30th, 60th and 90th day after operation. The result was that there was no significant difference between the two groups both in distribution and diameter of collagen fibers on the 15th and 30th days (P gt; 0.05). However, there was significent difference between those on the 60th and 90th days (P lt; 0.05). It was concluded that the severity of the tendon injury could influence the morphology of collagen fibers during the late stage of tendon healing.
Objective To repair the defects in articular cartilage with collagen complex gradient TCP in vivo andto study the regenerated cartilage histomorphologically. Methods The models of defects in articular cartilage were madeartificially in both condylus lateral is femoris of mature rabbits, male or female, with the weight of 2.0-2.5 kg. The right defects were implanted with the material of Col/TCP as the experimental group and the left defects were untreated as the control group. The rabbits were killed at 4, 6, 8, 12 and 24 weeks after operation, respectively, with 6 ones at each time, and the macroscopic, histological, ultrastructural examinations and semi-quantity cartilage scoring employing Wakitanifa repaired cartilage value system were performed. Results Four weeks after operation, the defects in the experimental group were partly filled with hyal ine cartilage. Twelve weeks after operation, the defects in the experimental group were completely filled with mature hyal ine cartilage. Twenty-four weeks after operation, regenerated cartilage had no ataplasia. However, fibrous tissues were seen in the control group all the time. At 4, 6, 8, 12 and 24 weeks ostoperatively, the Wakitanifa cartilage scores were 7.60 ± 0.98, 5.69 ± 0.58, 4.46 ± 0.85, 4.35 ± 0.12 and 4.41 ± 0.58, respectively, in the experimental group and 10.25 ± 1.05, 9.04 ± 0.96, 8.96 ± 0.88, 8.88 ± 0.68 and 8.66 ± 0.54, respectively, in the control group. At 4, 6, 8, 12 and 24 weeks postoperatively, the collagen II contents were 0.28% ± 0.01%, 0.59% ± 0.03%, 0.68% ± 0.02%, 0.89% ± 0.02% and 0.90% ± 0.01%, respectively, in the experimental group, while 0.08% ± 0.02%, 0.09% ± 0.04%, 0.11% ± 0.03%, 0.25% ± 0.03% and 0.29% ± 0.01%, respectively, in the control group. Differences between the control group and the experimental group were significant (P lt; 0.05). By then, typical chondrocyte was observed by transmission electron microscope in the experimental group and much fiber with less fibrocyte was observed in the control group. Conclusion Three-dimensional scaffold collagen complex gradient TCP may induce cartilage regeneration to repair the defects of articular cartilage in vivo.
Objective To investigate the morphological changes of the proximalfemur and their implication to the total hip arthroplasty in patients with Crowe Ⅱ/Ⅲ developmental dysplasia of the hip (DDH). Methods The experimental gr oup was composed of 15 hips in 14 patients (Crowe Ⅱ, 9 hips; Crowe Ⅲ, 6 hips ) with osteoarthritis secondary to Crowe Ⅱ/Ⅲ DDH (2 males, 12 females; age, 35-61 years). None of the patients had accepted any osteotomy treatment. The control group was composed of 15 normal hips in 15 patients with unilateral DDH (3 males, 12 females; age, 35-57 years). Twelve hips came from the experimental group and the other 3 came from the patients with unilateral Crowe Ⅰ DDH. The femurswere examined with the CT scanning. The following parameters were measured: theheight of the center of the femoral head (HCFH), the isthmus position (IP), theneckshaft angle(NS), the anteversion angle, the canal flare index, and the canal width. Then, the analysis of the data was conducted. Results HCFH and IP in theexperimental group and the control group were 50.1±6.7 mm, 50.1±7.4 mm, and 107.4±21.5 mm, 108.7±18.1 mm，respectively, which had no significant differencebetween the two groups（Pgt;0.05）. In the experimental group and the control group, the NS were 138.3±10.0° and 126.7±5.7°，the anteversion angles were 36.5±15.9° and 18.8±5.4°, and the canal flare indexes were 4.47±0.40and 5.01±0.43. There was a significant difference between the two groups in the above 3 parameters （Plt;0.05）. As for the canal width of the femur, therewasa significant difference in the interior/exterior widths and the anterior/posterior widths at the level of 2 cm above the lesser trochanter and 4 cm belowthe lesser trochanter between the two groups （Plt;0.05）; however, there was nosignificant difference in the canal width of the femur at the isthmus between the two groups（P＞0.05）. Conclusion It is necessary to evaluate the morphology of the proximal femur before the total hip arthroplasty performed in patients with Crowe Ⅱ/Ⅲ DDH. The straight and smaller femoral prosthesis should be chosen and implanted in the proper anteversion position duringoperation.
ObjectiveTo explore the clinical diagnosis and treatment of Talaromyces marneffei (TM) infection by bone marrow examination, and to clarify the important role and significance of bone marrow smear and pathogenic examination.MethodsRetrospective analysis was conducted on a case of disseminated TM infection that was clearly diagnosed through bone marrow related examination. Literature review of TM infection was conducted by retrieving relevant case reports at home and abroad from 1990 to 2018.ResultsThe patient was a 23-year-old man with recurrent cough and onset of fever, superficial lymph node enlargement in multiple parts of the body, no abnormal chest CT sign, and poor efficacy in anti-infection treatment. The patient developed progressive abdominal pain, accompanied by systemic papulosis, decreased consciousness, and progressive decline of blood cells. The patient underwent bone marrow puncture surgery in our hospital, and developed circulatory and respiratory failure half an hour after surgery. TM was confirmed bybone marrow smear and pathogenic culture. In the literature review, 2 855 cases of TM infection were retrieved, among which the majority of cases were confirmed through blood and bone marrow related examination. The positive rate of bone marrow culture was significantly higher than that of blood culture (72.4% and 66.8%, respectively, P=0.007). Compared with bone marrow culture, the misdiagnosis and missed diagnosis rate of bone marrow smear microscopy was 27.6%. Patients diagnosed with TM infection by bone marrow examination had the highest HIV positive rate (95.7%).ConclusionsThe examination of bone marrow cells and the culture are of great clinical significance for the diagnosis of TM infection. TM infection should be identified in patients suspected of HIV positive with fever, lymph node enlargement and abnormal blood routine.
Femtosecond laser small incision lenticule extraction (SMILE) with different residual stromal thicknesses (RST) is set to investigate its effect on corneal biomechanical properties of rabbits in vivo. In this study, 24 healthy adult Japanese rabbits were randomly divided into group A and B. The RST of group A was set 30% of the corneal central thickness (CCT), and the RST of group B was 50% of the CCT. The thickness of the corneal cap in both groups was set one third of CCT. Corneal visualization Scheimpflug technology (Corvis ST) and Pentacam three-dimensional anterior segment analyzer were used to determine corneal biomechanical and morphological parameters before surgery, and 1 week, 1 month and 3 months after surgery. Pearson correlation analysis was used to analyze factors affecting corneal biomechanical parameters after SMILE. The results showed that the corneal stiffness of group A was significantly higher than that of group B at 1 week and 1 month after surgery, and most biomechanical parameters returned to preoperative levels at 3 months postoperatively. The results of correlation analysis showed that postoperative CCT and RST were the main factors affecting corneal biomechanical parameters after SMILE. There was no significant difference in corneal posterior surface height (PE) between 3 months after surgery and before surgery in both two groups. It indicates that although the ability to resist deformation of cornea decreases in SMILE with thicker corneal cap and less RST, there is no tendency to keratoconus, which may be related to the preservation of more anterior stromal layer.
ObjectiveTo study a deep learning-based dual-modality fundus camera which was used to study retinal blood oxygen saturation and vascular morphology changes in eyes with branch retinal vein occlusion (BRVO). MethodsA prospective study. From May to October 2020, 31 patients (31 eyes) of BRVO (BRVO group) and 20 healthy volunteers (20 eyes) with matched gender and age (control group) were included in the study. Among 31 patients (31 eyes) in BRVO group, 20 patients (20 eyes) received one intravitreal injection of anti-vascular endothelial growth factor drugs before, and 11 patients (11 eyes) did not receive any treatment. They were divided into treatment group and untreated group accordingly. Retinal images were collected with a dual-modality fundus camera; arterial and vein segments were segmented in the macular region of interest (MROI) using deep learning; the optical density ratio was used to calculate retinal blood oxygen saturation (SO2) on the affected and non-involved sides of the eyes in the control group and patients in the BRVO group, and calculated the diameter, curvature, fractal dimension and density of arteriovenous in MROI. Quantitative data were compared between groups using one-way analysis of variance. ResultsThere was a statistically significant difference in arterial SO2 (SO2-A) in the MROI between the affected eyes, the fellow eyes in the BRVO group and the control group (F=4.925, P<0.001), but there was no difference in the venous SO2 (SO2-V) (F=0.607, P=0.178). Compared with the control group, the SO2-A in the MROI of the affected side and the non-involved side of the untreated group was increased, and the difference was statistically significant (F=4.925, P=0.012); there was no significant difference in SO2-V (F=0.607, P=0.550). There was no significant difference in SO2-A and SO2-V in the MROI between the affected side, the non-involved side in the treatment group and the control group (F=0.159, 1.701; P=0.854, 0.197). There was no significant difference in SO2-A and SO2-V in MROI between the affected side of the treatment group, the untreated group and the control group (F=2.553, 0.265; P=0.088, 0.546). The ophthalmic artery diameter, arterial curvature, arterial fractal dimension, vein fractal dimension, arterial density, and vein density were compared in the untreated group, the treatment group, and the control group, and the differences were statistically significant (F=3.527, 3.322, 7.251, 26.128, 4.782, 5.612; P=0.047, 0.044, 0.002, <0.001, 0.013, 0.006); there was no significant difference in vein diameter and vein curvature (F=2.132, 1.199; P=0.143, 0.321). ConclusionArterial SO2 in BRVO patients is higher than that in healthy eyes, it decreases after anti-anti-vascular endothelial growth factor drugs treatment, SO2-V is unchanged.
Characteristics in pulse wave signals (PWSs) include the information of physiology and pathology of human cardiovascular system. Therefore, identification of characteristic points in PWSs plays a significant role in analyzing human cardiovascular system. Particularly, the characteristic points show personal dependent features and are easy to be affected. Acquiring a signal with high signal-to-noise ratio (SNR) and integrity is fundamentally important to precisely identify the characteristic points. Based on the mathematical morphology theory, we design a combined filter, which can effectively suppress the baseline drift and remove the high-frequency noise simultaneously, to preprocess the PWSs. Furthermore, the characteristic points of the preprocessed signal are extracted according to its position relations with the zero-crossing points of wavelet coefficients of the signal. In addition, the differential method is adopted to calibrate the position offset of characteristic points caused by the wavelet transform. We investigated four typical PWSs reconstructed by three Gaussian functions with tunable parameters. The numerical results suggested that the proposed method could identify the characteristic points of PWSs accurately.