CircAKT3 alleviates postoperative cognitive dysfunction by stabilizing the feedback cycle of miR-106a-5p/HDAC4/MEF2C axis in hippocampi of aged mice.

Circular RNAs (circRNAs) have garnered significant attention in the field of neurodegenerative diseases including Alzheimer's diseases due to their covalently closed loop structure. However, the involvement of circRNAs in postoperative cognitive dysfunction (POCD) is still largely unexplored. To identify the genes differentially expressed between non-POCD (NPOCD) and POCD mice, we conducted the whole transcriptome sequencing initially in this study. According to the expression profiles, we observed that circAKT3 was associated with hippocampal neuronal apoptosis in POCD mice. Moreover, we found that circAKT3 overexpression reduced apoptosis of hippocampal neurons and alleviated POCD. Subsequently, through bioinformatics analysis, our data showed that circAKT3 overexpression in vitro and in vivo elevated the abundance of miR-106a-5p significantly, resulting in a decrease of HDAC4 protein and an increase of MEF2C protein. Additionally, this effect of circAKT3 was blocked by miR-106a-5p inhibitor. Interestingly, MEF2C could activate the transcription of miR-106a-5p promoter and form a positive feedback loop. Therefore, our findings revealed more potential modulation ways between circRNA-miRNA and miRNA-mRNA, providing different directions and targets for preclinical studies of POCD.

Intermittent Fasting on Neurologic Diseases: Potential Role of Gut Microbiota.

As the global population ages, the prevalence of neurodegenerative diseases is surging. These disorders have a multifaceted pathogenesis, entwined with genetic and environmental factors. Emerging research underscores the profound influence of diet on the development and progression of health conditions. Intermittent fasting (IF), a dietary pattern that is increasingly embraced and recommended, has demonstrated potential in improving neurophysiological functions and mitigating pathological injuries with few adverse effects. Although the precise mechanisms of IF's beneficial impact are not yet completely understood, gut microbiota and their metabolites are believed to be pivotal in mediating these effects. This review endeavors to thoroughly examine current studies on the shifts in gut microbiota and metabolite profiles prompted by IF, and their possible consequences for neural health. It also highlights the significance of dietary strategies as a clinical consideration for those with neurological conditions.

Farnesol Exerts Protective Effects against Chronic Sleep Deprivation-Induced Cognitive Impairment via Activation SIRT1/Nrf2 Pathway in the Hippocampi of Adult Mice.

SCOPE: Sleep deprivation (SD) negatively affects all aspects of health, with one serious consequence being impaired cognition. Farnesol (FOL) is a sesquiterpene synthesized by plants and mammals that has antioxidant, anti-inflammatory, and neuroprotective properties. This study investigates the mechanism underlying the neuroprotective effect of FOL on SD-induced cognitive impairment. METHODS AND RESULTS: Administration of FOL dramatically ameliorates chronic sleep deprivation (CSD)-induced cognitive impairment. In addition, FOL notably attenuates oxidative stress damage, pro-inflammatory cytokines activation, and microglial activation in the hippocampi of the CSD-exposed mice. Further examination indicates that administration of FOL after the CSD significantly increases the protein expressions of silent information regulator factor 2-related enzyme 1 (Sirt1), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and glutathione peroxidase 4 (Gpx4) in the hippocampi. Sirt1 agonist resveratrol (RES) has a similar neuroprotective effect, indicating that FOL could exert neuroprotective effects through the activation of the Sirt1/Nrf2 signaling pathway. CONCLUSION: The results reveal that FOL could protect against CSD-induced cognitive impairment by activating the Sirt1/Nrf2 signaling pathway.

Engineered biomimetic nanoreactor for synergistic photodynamic-chemotherapy against hypoxic tumor.

Photodynamic therapy (PDT) can produce a large amount of reactive oxygen species (ROS) in the radiation field to kill tumor cells. However, the sustainable anti-tumor efficacy of PDT is limited due to the hypoxic microenvironment of tumor. In this study, classic PDT agent indocyanine green (ICG) and hypoxia-activated chemotherapeutic drug tirapazamine (TPZ) were loaded on mesoporous polydopamine (PDA) to construct PDA@ICG-TPZ nanoparticles (PIT). Then, PIT was camouflaged with cyclic arginine-glycine-aspartate (cRGD) modified tumor cell membranes to obtain the engineered membrane-coated nanoreactor (cRGD-mPIT). The nanoreactor cRGD-mPIT could achieve the dual-targeting ability via tumor cell membrane mediated homologous targeting and cRGD mediated active targeting. With the enhanced tumor-targeting and penetrating delivery system, PIT could efficiently accumulate in hypoxic tumor cells and the loaded drugs were quickly released in response to near-infrared (NIR) laser. The nanoreactor might produce cytotoxic ROS under NIR and further enhance hypoxia within tumor to activate TPZ, which efficiently inhibited hypoxic tumor by synergistic photodynamic-chemotherapy. Mechanically, hypoxia-inhibitory factor-1α (HIF-1α) was down-regulated by the synergistic therapy. Accordingly, the cRGD-mPIT nanoreactor with sustainable and cascade anti-tumor effects and satisfied biosafety might be a promising strategy in hypoxic tumor therapy.

Emerging evidence on noncoding-RNA regulatory machinery in intervertebral disc degeneration: a narrative review.

Intervertebral disc degeneration (IDD) is the most common cause of low-back pain. Accumulating evidence indicates that the expression profiling of noncoding RNAs (ncRNAs), including microRNAs (miRNAs), circular RNAs (circRNAs), and long noncoding RNAs (lncRNAs), are different between intervertebral disc tissues obtained from healthy individuals and patients with IDD. However, the roles of ncRNAs in IDD are still unclear until now. In this review, we summarize the studies concerning ncRNA interactions and regulatory functions in IDD. Apoptosis, aberrant proliferation, extracellular matrix degradation, and inflammatory abnormality are tetrad fundamental pathologic phenotypes in IDD. We demonstrated that ncRNAs are playing vital roles in apoptosis, proliferation, ECM degeneration, and inflammation process of IDD. The ncRNAs participate in underlying mechanisms of IDD in different ways. MiRNAs downregulate target genes' expression by directly binding to the 3'-untranslated region of mRNAs. CircRNAs and lncRNAs act as sponges or competing endogenous RNAs by competitively binding to miRNAs and regulating the expression of mRNAs. The lncRNAs, circRNAs, miRNAs, and mRNAs widely crosstalk and form complex regulatory networks in the degenerative processes. The current review presents novel insights into the pathogenesis of IDD and potentially sheds light on the therapeutics in the future.

Adequate Restoration of Disc Height and Segmental Lordosis by Lumbar Interbody Fusion Decreases Adjacent Segment Degeneration.

OBJECTIVE: This study aimed to investigate the effects of lumbar interbody fusion-induced biomechanical changes on the adjacent segments, especially disc height and segmental lordosis restoration, and to provide more information for proper surgical strategy selection. METHODS: The medical records of 528 patients who underwent posterior lumbar interbody fusion were retrospectively reviewed, and a total of 89 patients were included. Surgical indications included degenerative spondylolisthesis (nonspondylolytic), marked disc herniation, or lumbar spinal stenosis requiring extensive decompression at L4/5. Postoperative adjacent segment degeneration (ASD) was assessed based on X-rays and functional status. Disc height, foraminal height, segmental lordosis, lumbar lordosis, and cage geometry were compared between the ASD and non-ASD patients. To identify the possible risk factors for radiographic ASD, univariate analysis was performed first, followed by multivariate logistic regression using variables with P < 0.20. RESULTS: Univariate analysis revealed that the postoperative disc height in the non-ASD group were significantly greater than in the ASD group. The postoperative segmental lordosis in the non-ASD group was significantly greater than that in the ASD group, and the lumbar lordosis in the non-ASD group was also significantly greater than that in the ASD group at the final follow-up visit. Four variables were identified as independent risk factors for ASD by subsequent multivariate logistic regression: postoperative relative disc height of L4/5 (P = 0.011), postoperative segmental lordosis (P = 0.046), lumbar lordosis at the final follow-up visit (P = 0.007), and cage height (P = 0.038). CONCLUSIONS: Improved lumbar lordosis is correlated with a lower incidence of ASD, and adequate disc height and segmental lordosis restoration are essential for ASD prevention.

Percutaneous reduction and intramedullary fixation technique for displaced pediatric radial neck fractures.

This study investigated the outcome of displaced pediatric radial neck fractures treated by percutaneous leverage reduction and intramedullary fixation using Kirschner wires. Twenty-three patients with displaced radial neck fractures were treated following this technique. Adequate reduction was achieved in each patient. Twenty-one patients were followed up for 37 months on average. All fractures healed. Malunion occurred in three patients with an average residual angulation of 7.3°. According to the MEPI, excellent outcome was achieved in 15 patients and good outcome in six. Therefore, this technique is an effective alternative for the treatment of pediatric radial neck fractures.

A proposed new system of coding and injury classification for arteries in the trunk and extremities.

STUDY DESIGN: Retrospective review of arterial injury with prospective intra-observer and inter-observer analyses. AIM: To introduce a new classification system for arterial injuries in the extremities and trunk. METHODS: Retrospective review of all patients with arterial injuries treated at a level I trauma centre during a 3.5-year period. Major arteries were located and coded, and the arteries' lesion was categorised in reference to the alphanumeric format of the AO fracture coding system and injury classification. Each major artery was coded in a numeric format and further divided into three segments: proximal, middle and distal. The severity of artery injury was classified into different types and subtypes in an alphanumeric format. Inter-observer and intra-observer reliabilities were tested. RESULTS: Systemic arteries were coded and arterial injuries were classified in the alphanumeric notation. The intra- and inter-observers' reliabilities were found to be acceptable in the application of the new system. CONCLUSION: The preliminary data demonstrate that the new coding and injury classification system for arteries in the trunk and extremities are reliable and efficient for data storage and retrieval, and provide a favourable environment for discussion among different physicians or centres.

An irreducible variant of femoral neck fracture: a minimally traumatic reduction technique.

We present 25 cases of irreducible variant femoral neck fractures that require surgical management after routine manipulative manoeuvre attempts have failed. In our study, an irreducible variant of femoral neck fractures is defined as a reduction that cannot be achieved after multiple attempts at closed reduction. This was evident radiographically, as seen in displaced­impacted femoral neck fractures when the proximal femur compacts and rotates along with the distal part, and anatomical reduction cannot be achieved with manipulative manoeuvres. Another rare situation also included is when the proximal fragment disconnects from the femur and dislocates as a 'floating' component, consequently resulting in failure of alignment of the distal fragment to the proximal femur.Here, we describe a technique, applied as a minimally traumatic procedure to achieve anatomic reduction in such cases. With the patient placed in supine position on the fracture table under general anaesthesia, the injury site is exposed and the procedure performed under intra-operative radiographic control. Location of the femoral artery is done first by palpation. The insertion site of the K-wires or Steinman pins on the proximal thigh is 1.5­3 cm lateral to the femoral artery. The K-wires or Steinmanpins are inserted vertically into the middle 1/2­2/3 of the femoral head and more than 1 cm inferior to the sub-chondral bone of the femoral head to a depth of approximately, 1/2 diameter of the femoral head. The pins are then used as a joystick to control the movement of the proximal femur. With the help of the K-wires, surgeons can manually control the movement of the proximal femur and ensure anatomic reduction with the distal fragment using routine-closed reduction. Three cannulated screws are used to stabilise the fracture after anatomic reduction is achieved and maintained in a stable position. All cases were treated with this minimally invasive procedure and internal fixation, 25 fractures united,uneventfully, whilst two of them developed femoral head necrosis at 10 months and 4.5 years postoperatively, respectively.

[Relationship between the cause and length of posterior malleolar fragment and treatment strategies for posterior malleolar fracture in adult patients].

OBJECTIVE: To explore the relationship between the causes and length of posterior malleolar fragment and treatment strategies of adult patients with three types of ankle joint injury. METHODS: The investigators recruited 233 cases of type C injury, 35 cases of type B injury and 91 cases of type A injury. Type A injury referred to simple ankle joint fracture with the involvement of posterior malleolar fragment. Type B injury tibial shaft fracture with ipsilateral ankle joint fracture. And posterior malleolar fracture line was the continuity of tibial shaft fracture line. Type C injury appeared similar to Type B injury, but tibial and malleolar fracture lines were not continued. The ratio between the length of posterior malleolar articular and the total length of articular surface was calculated in theses three types of injuries in sagittal CT scan slice. Different treatment regimens were used to manage the posterior malleolar fractures. And visual analogue score (VAS) was introduced to assess the therapeutic outcomes. RESULTS: The ratio between the length of posterior malleolar articular and the total length of articular surface decreased from Type A to Type C (χ(2) = 187.453, P = 0.0000). The ratio was (34 ± 15)% for Type A, (30 ± 9)% for Type B and (12 ± 10)% for Type C. A follow-up study was performed in Type A injury (n = 58), Type B injury (n = 31) and Type C injury (n = 167) at 12 months. According to VAS score, there was no significant difference between the patients undergoing fixation and not (all P > 0.05). CONCLUSION: Different causes of posterior malleolar fracture results in different sizes of posterior malleolar fragment and strategies of treatment. The anatomic reduction of posterior malleolar fragment remains a key aspect of achieving satisfactory outcomes in all kinds of injury.

The study of plate-screw fixation in the posterior wall of acetabulum using computed tomography images.

OBJECTIVE: The article aims to delineate the width of posterior column, the thickness of posterior wall, and safe angles for screw placement in the posterior wall to avoid intraarticular screw penetration. METHODS: The computed tomography (CT) images of 32 cadaveric adult bony hemipelvic specimens were initially obtained for the purpose of the study. Each specimen was sectioned at 1-cm intervals, and each plane of the crosssection was perpendicular to the surface of posterior column. By analyzing the CT images postprocessed with multiplanar reconstruction, the width of posterior column, the thickness of posterior wall, and the modified safe angle for screw placement in the posterior wall were measured and recorded. To validate the data obtained from the cadaveric model, this method was applied on 30 adult volunteers. The corresponding data were recorded and compared with those acquired from the cadaveric bony hemipelvis. In efforts to approve the usefulness of this method in practice, we have performed screw insertions in another 10 acetabular specimens and two operative cases by using the data from analyzing the CT images. RESULTS: The width of posterior column, the thickness of posterior wall, and the safe angles for screw insertion in the posterior wall were measured and recorded in both specimens and volunteers. Comparison of the corresponding data was made between specimens and volunteers, and no significant difference was found in the same gender and side (p > 0.05). The corresponding width of posterior column, thickness of posterior wall, and safe angles for screw placement was found to be statistically different between males and females in both specimens and volunteers (p < 0.05). In specimens group, the safe angles for the entry points 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 cm medial to the lateral acetabular brim were 49.23 degrees +/- 11.54 degrees, 42.48 degrees +/- 8.97 degrees, 29.53 degrees +/- 7.86 degrees, 23.68 degrees +/- 6.20 degrees, 18.42 degrees +/- 5.41 degrees and 15.91 degrees +/- 4.37 degrees in males and the corresponding angles for the entry points 0.5, 1.0, 1.5, 2.0, and 2.5 cm medial to the lateral acetabular brim were 45.02 degrees +/- 8.82 degree, 35.98 degrees +/- 7.60 degrees, 23.77 degrees +/- 6.29 degrees, 19.96 degrees +/- 4.36 degrees, and 14.68 degrees +/- 3.48 degrees in females, respectively. CT images of 10 acetabular specimens and two cases with posterior wall fractures show all screws were inserted into the posterior wall without penetration into the joint space. CONCLUSIONS: The oblique multiplanar reconstruction images perpendicular to the surface of posterior column were selected to describe the safe angle for screw insertion into posterior wall, which can provide consistent results in both specimens and volunteers. The method can be applied in practice both on acetabular specimens and operative cases and is helpful to make individual perioperative planning for safer fixation of posterior wall fracture.

[The effects of the autologous venous external stents on intimal hyperplasia of the vein grafts in rabbits].

OBJECTIVE: To assess the effect of the autologous venous external stents on intimal hyperplasia of the vein grafts in rabbits. METHODS: Thirty-six male New Zealand white rabbits, aged 5 months and weighing 2.8 to 3.0 kg, were randomly divided into 3 groups: group A, group B and group C, with 12 rabbits in each group. First, a section about 6 cm long of vein was cut from the right external jugular vein of each rabbit and severed to have 3 equal-length segments. Next, each distal segment prepared for anastomosis. The proximal segment invaginating middle segment in group A and only middle segment in group B were used for the external stent. Later, the left common carotid artery was separated from surrounding tissue, from it a section about 0.5 cm long was cut away. Finally, the vein graft was inverted and end-to-end anastomosed to the two ends of the artery with a 9-0 suture. After bloodstream re-established, the diameter of each vein graft was measured. At 2 and 4 weeks postoperative, the graft veins were cut off and histologically examined by the means of HE staining and Masson staining. The smooth muscle cells (SMC) proliferation was studied by the immunohistochemical detection of proliferating cell nuclear antigen. RESULTS: After bloodstream re-established, the diameters of vein graft of group A and group B and group C were (1.6 +/- 0.3) mm, (2.2 +/- 0.4) mm and (2.6 +/- 0.6) mm respectively (P < 0.05). At 4 weeks postoperative, the data of the ratio of intima to media thickness and the index of the proliferating cells of the intima were as follow: group A (1.01 +/- 0.07 and 6.84 +/- 1.98), group B (1.32 +/- 0.08 and 11.01 +/- 2.61), group C (1.55 +/- 0.03 and 14.96 +/- 4.14). Both the data of group A were obviously less than that in group B, and that of group B was less than group C (P < 0.05). CONCLUSION: The autologous venous two-layer external stents inhibit intimal hyperplasia of the vein grafts.

[Experimental study on rho-kinase inhibitor by intravenous injection inhibiting intimal hyperplasia in vein grafts].

OBJECTIVE: To investigate the effects of Rho-kinase inhibitor--fasudil hydrochloride hydrate on vein graft intimal hyperplasia in vivo. METHODS: Twenty-four healthy rabbits (2.3-2.5 kg) were randomly divided into two groups (n=12). Fasudil hydrochloride hydrate (experimental group) and normal sodium (control group) were given 3 days before operation with 30 mg/kg by intravenous injection everyday and continued until the end of the experiment. After a longitudinal incision, the femoral vein and the femoral artery were exposed about 3 cm. An approximately 2.5 cm segment of the famoral vein was harvested for the reversed-vein graft. The femoral artery was removed 1 cm segment and replaced by the harvested femoral vein. At 2 and 4 weeks after operation, the grafts were stained with HE to observe the thickness of the intima. Furthermore, the proliferating cell nuclear antigen (PCNA) and transmission electron microscope was used to study the proliferation of smooth muscle cell. In situ apoptosis was detected by TUNEL assay. RESULTS: All rabbits survived till the end of the experiment. The color Doppler imaging examination showed that all grafts were patency. At 2 and 4 weeks after the operation, HE staining showed that the intimal hyperplasia were obvious in the two groups. There were lots of cells in the intima, and more fusiform smooth muscle cells in the media. At 2 and 4 weeks, the intimal thickness were (30.33 +/- 3.23) microm and (43.11 +/- 4.92) microm in experimental group and were (44.83 +/- 3.53) microm and (66.16 +/- 8.45) microm in control group. The rates of PCNA positive cell were 14.28% +/- 2.76% and 7.61% +/- 1.06% in experimental group and were 20.08% +/- 3.56% and 8.73% +/- 1.35% in control group. The rates of TUNEL positive cell were 3.55% +/- 0.36% and 1.22% +/- 0.18% in experimental group and were 1.11% +/- 0.31% and 0.55% +/- 0.11% in control group. There were significant differences (P < 0.05) between the two groups at 2 weeks or 4 weeks, between 2 weeks and 4 weeks within group. CONCLUSION: Intravenous injection of fasudil hydrochloride hydrate is an effective method for prevention of vein graft intimal hyperplasia of rabbit.

[Quantitative evaluation of postoperative effect of calcaneal fractures using Footscan system].

OBJECTIVE: To investigate the value of using Footscan system to evaluate the therapeutic effect of two internal fixation methods on calcaneus fractures. METHODS: From February 2006 to September 2006, 64 patients with fresh unilateral closed calcaneus fractures were randomly divided into two groups. The experimental group: 32 patients underwent minimally invasive open reduction and internal fixation with improved compressing plate and screw, including 28 males and 4 females aged 20-53 years old (average 36.7 years old); the course of disease was 3-14 days; there were 19 cases of type II, 11 of type III, and 2 of type IV according to Sanders fracture classification system. The control group: 32 patients underwent internal fixation of standard AO plate via L-shaped incision, including 29 males and 3 females aged 18-56 years old (average 37.1 years old); the course of disease was 4-15 days; there were 18 cases of type II, 11 of type III and 23 of type IV according to Sanders fracture classification system. No significant difference was noted between two groups in the general information (P > 0.05). At 1 and 2 years after operation, dynamic plantar pressure was measured using Footscan system, Maryland foot scores of two groups was compared, and statistical analysis was performed. RESULTS: All patients were followed up for 2 years. No infection, cuticular border necrosis, and sural nerve distal end injury occurred in the experimental group, whereas in the control group, 3 patients suffered from cuticular border necrosis and recovered after dressing, and 1 patient had sural nerve distal end injury with decreased sensation in local skin. At 1 and 2 years after operation, in the control group, there were significant differences between the injured foot and the normal foot in terms of impulse, instep index, motion range of subtalar joint, lateral displacement of footplate pressure center, and calcaneal width when patients stood on both feet (P < 0.05), whereas in the experimental group, no significant differences were noted between the injured foot and the normal foot in terms of the above parameters (P > 0.05). Significant differences were noted between two groups in terms of the above parameters (P < 0.05). The Maryland score 1 year after operation was (86.74 +/- 8.56) points for the experimental group and (71.24 +/- 10.06) points for the control group; at 2 years after operation, it was increased to (87.35 +/- 8.49) points and (72.41 +/- 9.69) points, respectively, indicating there was a significant difference between two groups (P < 0.05). CONCLUSION: Operative outcomes of internal fixation with improved compressing plate are superior to those of standard AO plate. Footscan system can provide a quantitative assessment on the operative effect of calcaneus fractures.

[Inhibitory effect of topical application of 5-fluorouracil on intimal hyperplasia of vein graft].

OBJECTIVE: To assess the effect of topical application of 5-fluorouracil (5-FU) on intimal hyperplasia in rabbit vein graft. METHODS: Sixty-four male New Zealand white rabbits, aged 5 months and weighing 2.8-3.0 kg, were randomly divided into group A, B, C, and D (n = 16 rabbits per group). Artery defect model was established by cutting about 1 cm artery from the middle part of the dissociated left common carotid artery. A section about 3 cm was cut from the right external jugular vein, and the harvested vein was inverted and end-to-end anastomosed to the artery defect with 9-0 non-traumatic suture. After anastomosis, the extima of the grafted veins in group A, B, and C was completely wrapped with cotton sheet (12 mm x 30 mm x 1 mm in size) immersed by 5-FU at a concentration of 50.0, 25.0, and 12.5 mg/mL, respectively, and each vein was treated 5 times (1 minute at a time). In group D, the extima of the graft veins was treated with normal saline instead of 5-FU. The grafted veins were obtained 1, 2, 4, and 6 weeks after operation, HE staining and Masson staining were preformed for histological changes of grafted vein wall, proliferating cell nuclear antigen (PCNA) immunohistochemistry staining and TUNEL labeling staining were conducted for proliferation and apoptosis of smooth muscle cell of the grafted vein, and transmission electron microscope observation was performed for cellular ultrastructure. RESULTS: The HE staining, Masson staining, and PCNA immunohistochemistry staining showed that the thickness of intima in group A and B was obviously less than that in group C and D at 1, 2, 4, and 6 weeks after operation, and the proliferation cells in group A and B were less than that in group C and D at 1, 2, and 4 weeks after operation. The thickness of the intima, the degree of intima hyperplasia, the degree of vessel lumen stenosis of four groups at different time points were as follows: at 1 week after operation, group A [(12.69 +/- 1.68) microm, 0.73 +/- 0.05, 0.025 +/- 0.003], group B [(17.52 +/- 2.01) microm, 0.86 +/- 0.06, 0.027 +/- 0.004], group C [(21.92 +/- 1.85) microm, 1.06 +/- 0.09, 0.036 +/- 0.006] and group D [(26.45 +/- 3.86) microm, 1.18 +/- 0.08, 0.041 +/- 0.005]; at 2 weeks after operation, group A [(24.61 +/- 2.91) microm, 0.86 +/- 0.06, 0.047 +/- 0.003], group B [(37.28 +/- 2.78) microm, 1.17 +/- 0.09, 0.060 +/- 0.004], group C [(46.52 +/- 2.25) microm, 1.44 +/- 0.08, 0.073 +/- 0.003], and group D [(52.07 +/- 3.29) microm, 1.45 +/- 0.05, 0.081 +/- 0.006]; at 4 weeks after operation, group A [(61.09 +/- 6.84) microm, 1.38 +/- 0.08, 0.106 +/- 0.007], group B [(63.61 +/- 8.25) microm, 1.40 +/- 0.07, 0.107 +/- 0.010], group C [(80.04 +/- 7.65) microm, 1.64 +/- 0.07, 0.129 +/- 0.011], and group D [(84.45 +/- 9.39) microm, 1.68 +/- 0.10, 0.139 +/- 0.014]; at 6 weeks after operation, group A [(65.27 +/- 5.25) microm, 1.46 +/- 0.07, 0.113 +/- 0.005], group B [(65.82 +/- 7.12) microm, 1.45 +/- 0.05, 0.112 +/- 0.011], group C [(84.45 +/- 9.39) microm, 1.69 +/- 0.09, 0.135 +/- 0.007], and group D [(87.27 +/- 8.96) microm, 1.76 +/- 0.05, 0.140 +/- 0.012]. Group A and B were inferior to group C and D in terms of the above three parameters and cell proliferation index 1, 2 and 4 weeks after operation (P < 0.05). Group A and B were superior to group C and D in terms of cell apoptosis index of intima and media 1 and 2 weeks after operation (P < 0.05). Transmission electron microscope observation showed that the synthetic cell organelles such as rough endoplasmic reticulum, golgi apparatus, and ribosome in group A and B were obviously less than those in group C and D (P < 0.05). CONCLUSION: Topical application of 5-FU can effectively inhibit intima hyperplasia of the vein grafts.

[Marine inorganic carbon system responses to macro-DIN supply coupled with Ulva pertusa in simulated experiments].

Effects of macronutrient (NO3(-) -N and NH4(+) -N) on inorganic carbon system of water with Ulva pertusa existed were studied in laboratory simulation experiments. The results demonstrated that nutrient enrichment induced DIC, HCO3- and p(CO2) decreased while pH and CO3(2-) increased. The seawater changed from carbon source to carbon sink. During the experiments, the concentration of DIC, HCO3- and p(CO2) decreased with increasing concentration of nutrient when the NO3(-) -N and N4(+) -N were less than critical concentration. The concentration of DIC changed most at the NO3(-3) and NH4(-)3 groups, which decreased 151 micromol x L(-1) and 232 micromol x L(-1) compared with the control groups in the end of experiment. The increased dry weight of Ulva pertusa (deltam) of nutrient addition groups showed a significant negative correlation with deltaDIC (r = - 0.91, p < 0.0001, n = 11). The main controlling factor to inorganic carbon variation is the adaptation of Ulva pertusa to different DIN. When the concentration of DIN facilitates the growth of Ulva pertusa, the concentration of DIC decreased and dry weight of Ulva pertusa increased. NH(4) -N has more influence on inorganic carbon system than NO(3-) -N.

[Clinical observation on the different treatments targeted at different types of radial head fracture and radial neck fracture].

OBJECTIVE: To assess the effect of the different treatments targeted at different types of radial head fracture and radial neck fracture. METHODS: A retrospective study was performed in 87 patients from February 2006 to March 2007. Fifty-four patients with radial head fractures included 36 males and 18 females, aged from 18 to 65 years (the average age was 33); Forty of them resulted from crashing, 8 from traffic injury and 6 from falling injury. According to Mason classification system, there were 15 type I, 23 type II and 16 type III. Thirty-three patients with radial neck fractures included 21 males and 12 females, aged from 9 to 17 years (the average age was 13), 29 of them resulted from crashing, 1 from traffic injury and 3 from falling injury. According to O'Brien classification system, there were 8 type I, 14 type II and 11 type III. Type I of radial head fractures and radial neck fractures were immobilization with cast, the patients with type II of radial head fractures were treated with open reduction and micro-screw or T-trapezoid and bridge-shaped plate fixation and type III had operations to fix with bridge-shaped locked plate and repair the broken annular ligament, or replace heads with prosthesis. All patients with type II and type III of radial neck fractures were treated with closed reduction by leverage and percutaneous intra-medullary nailing. RESULTS: The patients were followed up for 4-12 months (mean 7.2 months). The functional recovery degrees were evaluated with Wheeler's evaluation system. In group of radial head fractures, the results were excellent in 26 patients, good in 20, fair in 6 and poor in 2, the excellent and good rate was 85.2%. In group of radial neck fractures, the results were excellent in 20 patients, good in 9, fair in 4 and poor in no patient, and the excellent and good rate was 87.9%. CONCLUSIONS: Different types of fractures should choose different surgical methods according to their characters. The excellent functional recovery depend on anatomical reduction, retaining the head of radius, early repairing and protecting the broken annular ligament of radius, and early functional training.

[Biomechanical study on the calcaneal fracture fixed by the self-designed calcaneal anatomical plate and pre-cut gudgeon].

OBJECTIVE: To study the biomechanical properties of self-designed calcaneal anatomical plate and pre-cut gudgeon system and its efficacy for calcaneal fracture fixation. METHODS: Sixteen fresh foot specimens were randomly divided into experimental group and the control group. Axial compressive load were applied to all specimens in order to create a calcaneal fracture model, and the maximum load and the maximum arch displacement of experimental group were recorded. In experimental group, self-designed intenal fixation system were utilized, while the AO plate internal fixation system were utilized in the control group. Axial compressive test were applied again to both groups, and the maximum load, the foot arch displacement and calcanus broadens were measured and recorded. RESULTS: Comparison between before and after fixing the calcaneus fracture by self-designed internal fixation system in experimental group, the difference of the maximum load was significant (P<0.01), but there was no significant difference (P>0.05) of the maximum arch displacement. All parameters were significantly different (P<0.01) between the experimental group and the control group. CONCLUSION: The fractured calcaneus will be able to regain normal foot biomechanical function after treated by self-designed internal fixation system, and able to support foot arch to bear great load. The self-designed internal fixation and pre-cut gudgeon system is considered to outperform the conventional AO internal fixation system with its better effectiveness and outcome in treating calcaneus fractures.

[Effects of 5-fluorouracil on tendon adhesion formation after flexor tendon repair].

OBJECTIVE: To evaluate the effect of 5-fluorouracil (5-FU) applied topically on preventing adhesion and promoting functional recovery after tendon repair. METHODS: From August 2003 to June 2007, 48 patients with flexor tendon rupture of the fingers by sharp instrument were treated and randomly divided into two groups. In 5-FU group, 39 fingers of 26 patients included 17 males and 9 females, aged (29.3 +/- 9.8) years; the locations were zone I in 19 fingers and zone II in 20 fingers; single finger was involved in 12 cases and more than 2 fingers were involved in 14 cases; and the time from injury to operation was (2.4 +/- 1.6) hours. In control group, 36 fingers of 22 patients included 14 males and 8 females; aged (26.1 +/- 8.7) years; the locations were zone I in 16 fingers and zone II in 20 fingers; single finger was involved in 10 cases and more than 2 fingers were involved in 12 cases; and the time from injury to operation was (2.1 +/- 1.8) hours. No statistically significant difference was found in constituent ratio of age, gender, injured fingers and their zones, between two groups (P > 0.05). The repair site in 5-FU group was given 5-FU at a concentration of 25 mg/mL with a soaked sponge, and the synovial sheath of the repaired site was wrapped with the 5-FU-soaked sponge for 1 minute for 4 times after the tendons were repaired; normal saline was used in the control group. RESULTS: Wound healed by first intention and no infection and tendon rupture occurred in two groups. The patients were followed up for 3-8 months (mean 4.1 months) and 3-8 months (mean 3.9 months) in 5-FU group and in control group respectively. The functional recovery degrees of the fingers were evaluated with total active movement (TAM) evaluation system. In 5-FU group, the results were excellent in 22 fingers, good in 13 fingers, fair in 3 fingers and poor in 1 finger; the excellent and good rate was 89.7%. In control group, the results were excellent in 11 fingers, good in 15 fingers, fair in 9 fingers and poor in 1 finger; the excellent and good rate was 72.2%. There was statistically significant difference in the functional recovery degrees of fingers between two groups (P < 0.05). The 2 fingers which had a poor result in 5-FU group and control group were served with tenolysis was performed in 2 cases having poor results after 6 months of operation and had an excellent result at last. CONCLUSION: 5-FU applied topically can reduce tendon adhesions after the ruptured tendon repair.

[An effect of 5-fluorouracil on tendon adhesion formation after flexor tendon repair in chickens].

OBJECTIVE: To assess an effect of 5-fluorouracil (5-FU) applied topically on the tendon adhesion and the healing process after the flexor tendon repair in Leghorn chickens. METHODS: Thirty-two white Leghorn chickens, aged 4 months and weighing 1.5-1.7 kg, were randomly divided into 2 groups: Group A and Group B, with 16 chickens in each group. The flexor digitorum profundus tendons of the 2nd, 3rd and 4th toes were transected and repaired. The repair site in Group A was given 5-FU in a concentration of 25 mg/ml with a soaked sponge that was cut into pieces 7 mm X 20 mm x 1 mm in size, and the synovial sheath of the repair site was wrapped with the 5-FU-soaked sponge for 1 min for 4 times. The repair site in Group B was served as a control, with no 5-FU but with the sterile normal saline. At 3 and 6 weeks postoperatively, the repaired tendons and the tendon adhesion formation were examined macroscopically and histologically, and the repaired tendons were tested biomechanically. The tissue blocks from the tendon repair site were examined under the transmission electron microscope. RESULTS: At 3 and 6 weeks postoperatively, the macroscopic and histological observation showed that the peritendinous adhesions in Group A were looser when compared with those in Group B. The length of the tendon gliding and the extent of yieldance to exercise were found to be 4.85+/-1.31 mm, 0.67+/-0.42 mm and 5.74+/-1.61 mm, 1.55+/-0.35 mm respectively at 3 and 6 weeks after operation in Group A,but 2. 99+/-0.51 mm,0.24+/-0.14 mm and 3.65+/-0.54 mm, 1.22+/-0.16 mm in Group B. Group A was significantly greater in the above-mentioned parameters than Group B (P<0.05). At 3 weeks after operation, the ultimate breaking strength was 20.28 +/- 4.92 N in Group A and 21.29 +/- 4.88 N in Group B, with no statistically significant difference found between the two groups (P>0.05). At 6 weeks, the ultimate breaking strength was 47.12+/-6.76 N in Group A but 39. 31 +/- 7.20 N in Group B, with a significant difference between the two groups (P < 0.05). CONCLUSION: 5-fuorouracil, when applied topically, can reduce the tendon adhesion, with no inhibition of the intrinsic healing mechanism. It is an ideal treatment strategy to prevent peritendinous adhesion.