Experimental Study on Rapid Hemostasis Using Peptide Hydrogels.

Uncontrolled hemorrhaging resulting from trauma, surgery, and disease-associated or drug-induced blood disorders can cause significant morbidities and mortalities in civilian and military populations. Self-assembling peptide nanofibers are particularly attractive due to their rapid and efficient hemostasis, biocompatibility, and wound-healing properties. In this study, we designed two types of 12-residue peptides by using a strong fishnet-like peptide sequence and a pro-cell adhesion sequence (Arg-Gly-Asp, RGD). The peptides are HN2-X-Ser-Phe-Cys-Phe-Lys-Phe-Glu-X-Arg-Gly-Asp-OH (where X is Pro or Tyr), which dissolve in deionized (DI) water and form stable and transparent functional hydrogels. Transmission electron microscopy and scanning electron microscopy demonstrated that the two peptides self-assemble into nanowebs and nanofibers, forming a fishnet-like and three-dimensional network structure. Circular dichroism and Fourier transform infrared spectroscopy analysis demonstrated that the self-assembled peptides mainly adopt a ß-sheet structure with ß-turn and α-helix as auxiliary assembly growth. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and SEM analysis showed that the cell survival rates were very good, delivering an obvious promotion of cell proliferation of fibroblasts and hepatocytes. Importantly, in vivo hemostasis delivered that the self-assembled peptide nanowebs and nanofibers had a good hemostatic effect on rat saphenous vein and liver bleeding, achieving 38 s faster hemostasis, which was better than commercial "Instantaneous" hemostatic powder. Accoupling the fast hemostasis and effective promotion of liver defect rapid repair, the peptide self-assembly strategy offers a clinically promising treatment option for life-threatening liver bleeding and serves as a renewed impetus for the development of peptide hydrogels as effective hemostatic agents.

A retrospective assessment of the clinical efficacy of different internal fixation methods in the treatment of distal fibula fractures in the elderly.

An ankle fracture is a fracture of the distal tibia or fibula that forms the ankle joint, usually associated with ligament and soft tissue injury, and is a common type of lower limb fracture and one of the most common types of fracture in the elderly. Although ankle fractures are one of the most common injuries seen by orthopedic trauma surgeons, there is no uniform protocol for the diagnosis and treatment of ankle fractures in the elderly, and there are many controversial indications for surgery. The aim of this study is to assess the clinical efficacy of different internal fixation methods in the treatment of distal fibular fractures in the elderly, in an effort to improve the rational selection and application of clinical acts. A retrospective analysis was performed on 68 cases of patients who suffered an ankle fracture and were treated with different internal fixation methods according to the fracture types and individual differences in distal fibula fractures. The postoperative therapeutic effect assessment was performed in terms of clinical examination, imaging evaluation, and AOFAS ankle-hind foot function scoring. There was no unhealed bone, ankle instability and loose/fractured internal fixation. Fracture healing time was 2.7 to 4.0 months (average 3.2 months). AOFAS score was 88.3 ± 6.2, of which, 34 excellent cases, 30 good cases, and 4 fair cases. Ankle activity dorsiflexion 6º~18º, average 15º; plantar flexion 26º~47º, average 37º. A good clinical efficacy could be achieved from the most appropriate individualized internal fixation for distal fibula fractures of elderly patients.

Regulation of osteoblast autophagy based on PI3K/AKT/mTOR signaling pathway study on the effect of ß-ecdysterone on fracture healing.

OBJECTIVES: To investigate the effects of ß-ecdysterone on fracture healing and the underlying mechanism. METHODS: MTT assay was used to detect the cell viability. AO/PI and flow cytometry assays were used to determine the apoptotic rate. The expression level of RunX2, ATG7 and LC3 was evaluated by qRT-PCR and Western blot assays. X-ray and HE staining were conducted on the fractured femur. Immunohistochemical assay was used to detect the expression level of Beclin-1 and immunofluorescence assay was used to measure the expression level of LC3 in the fractured femurs. Western blot was utilized to determine the expression level of PI3K, p-AKT1, AKT1, p-mTOR, mTOR, p-p70S6K, and p70S6K. RESULTS: The ALP activity and the expression of RunX2 in fractured osteoblasts were significantly elevated, the apoptotic rate was suppressed by rapamycin, 60, and 80 µM ß-ecdysterone. The state of autophagy both in fractured osteoblasts and femurs was facilitated by rapamycin and ß-ecdysterone. Compared to control, Garrett score was significantly promoted in rapamycin and ß-ecdysterone groups, accompanied by ameliorated pathological state. Lastly, the PI3K/AKT/mTOR pathway both in fractured osteoblasts and femurs was inhibited by rapamycin and ß-ecdysterone. CONCLUSION: ß-ecdysterone might facilitate fracture healing by activating autophagy through suppressing PI3K/AKT/mTOR signal pathway.

ß-ecdysterone alleviates osteoarthritis by activating autophagy in chondrocytes through regulating PI3K/AKT/mTOR signal pathway.

PURPOSE: To investigate the therapeutic effects of ß-ecdysterone on osteoarthritis (OA) and the underlying mechanism. METHODS: OA model was established on rats by injecting MIA. ELSA was used to determine the concentration of IL-1ß, IL-6, NO and TNF-α in the chondrocytes and cartilage tissues. Immunofluorescence assay was used to determine the expression of collagen II in the chondrocytes. The survival rate of chondrocytes was evaluated by MTT assay. The apoptosis of chondrocytes was checked by AO/PI staining and flow cytometry assay. The expression level of Atg7, PI3K and caspase-3 was evaluated by qRT-PCR. Western Blot was used determine the expression of PI3K, p-AKT1, AKT1, p-mTOR, mTOR, p70S6K, p-p70S6K, LC3I, LC3II and caspase-3. HE staining was used to check the pathological state of cartilage tissues. RESULTS: Chondrocytes were tolerable to rapamycin, 3-methyladenine and ß-ecdysterone at the concentration of 10 mM, 100 nM and 40 µM, respectively. The apoptosis of chondrocytes was inhibited by rapamycin and ß-ecdysterone, and induced by 3-methyladenine. PI3K, p-AKT1, p-mTOR, p-p70S6K and caspase-3 were down-regulated by rapamycin and ß-ecdysterone, and up-regulated by 3-methyladenine in both the chondrocytes and the cartilage tissues. The expression of Atg7 and LC3II/LC3I were regulated in a opposite way. The inflammation state was improved by rapamycin and ß-ecdysterone both the chondrocytes and the cartilage tissues. HE staining results showed that the pathological state of cartilage tissues was alleviated by ß-ecdysterone. CONCLUSION: ß-ecdysterone might alleviate osteoarthritis by activating autophagy in chondrocytes through regulating PI3K/AKT/mTOR signal pathway.

Lipoxin A4 protects rat skin flaps against ischemia-reperfusion injury through inhibiting cell apoptosis and inflammatory response induced by endoplasmic reticulum stress.

BACKGROUND: The ischemia-reperfusion (I/R) injury of skin flap is a complex pathophysiological process involving many cells and factors. Although endoplasmic reticulum (ER) stress-induced cell apoptosis and inflammatory response are of immense importance in the skin flap ischemia, the treatment for I/R injury induced by ER stress is barely reported. METHODS: Healthy male Wister rats were randomly divided into three groups: sham-operated group, I/R model group and I/R + LXA4 group. I/R-induced injury in skin flaps with or without pre-treatment of Lipoxin A4 (LXA4, 100 µg/kg) was tested by using HE and TUNEL staining. Related factors associated with oxidative stress, apoptosis, inflammatory response, and ER stress were tested by ELISA, biochemical assay, and western blotting, respectively. RESULTS: Our results showed that LXA4 treatment significantly promotes skin flap survival and attenuates I/R injury by inhibiting oxidative stress, apoptosis, and inflammatory factor release, evidenced by the decreased expression of malondialdehyde (MDA), lactate dehydrogenase (LDH), NF-κBp65, tumor necrosis factor α (TNF-α), ET, active Caspase-3 and Bax and up-regulated superoxide dismutase (SOD), glutathione (GSH) level and Bcl-2 expression. Moreover, LXA4 treatment also reverses the increased expression of GRP78, p-PERK, p-eIF2α, ATF4, and CHOP induced by I/R injury. CONCLUSIONS: In conclusion, we showed that ER stress causes cell apoptosis and inflammatory response, resulting in the skin flaps injury. LXA4 exhibits a protective effect on skin flaps against I/R injury through the inhibition of ER stress.

[Progress on prevention and treatment of heterotopic ossification].

Heterotopic ossification is the formation of pathological bone in non-skeletal tissues (including muscles, tendons or other soft tissues), and the pathogenesis is not completely clear. It is often caused by musculoskeletal trauma, postoperative bone and joint surgery, or damage of the nervous system, the clinical manifestations are joint swelling, pain, and movement disorders, which often occur around the hips, knees, and elbows. At present, the prevention of heterotopic ossification mainly includes drugs, radiotherapy, molecular biological mechanism intervention, and Chinese medicine-related measures. Among them, drugs and radiotherapy are more effective methods to prevent heterotopic ossification. The intervention of molecular biology mechanism to prevent heterotopic ossification has become a new research direction and focus of attention inrecent years, and is basically at the experimental research stage. The treatment of heterotopic ossification includes various methods such as drugs, physical therapy, and surgery. Among them, surgery is recognized as the most effective treatment, however there are still some controversies and disagreements about the choice of operation time and surgical methods.

[Three-step sequential method for limb skin and soft tissue defect combined with bone or tendon exposed wound].

OBJECTIVE: To explore clinical effect of VSD technology, coverage of artificial dermis and autograft for the treatment of limb skin soft tissue defect combined with bone or tendon exposed wound. METHODS: Eighteen patients suffered from limb skin soft tissue defect combined with bone or tendon exposed wound treated by three-step sequential method from January 2013 to June 2015. Among them, including 13 males and 5 females aged from 23 to 72 years old with an average of 34.6 years old; the time from injury to operation ranged from 1.5 to 5.0 hours with an average of 2.5 h. The area of skin and soft tissue injury ranged from 4.2 cm×3.1 cm to 7.4 cm×5.2 cm. Wound recovery and taken skin wound recovery were observed to evaluate clinical results. RESULTS: All patients were followed up from 5 to 16 months, with an average of 7.6 months. Deep bone tendon tissue of wounds were effectively recovered, artificial dermis survived, and quality of healed wound was tough and shape was good. Wound transplant flap was survived, no obvious scar tissue formation, appearance was flat, skin color was a little deeper than normal skin, the overall effect was satisfactory. CONCLUSIONS: Three-step sequential method has good curative effect for patients suffered from limb skin soft tissue defect with bone or tendon exposed wound and refused to repair the flap, and has advantage of simple operation, operation risk, less invasive.

[Different mini skin flaps in repairing finger soft tissue with bone defect].

OBJECTIVE: To explore surgical methods and clinical effects of three different types of mini skin flap transplantation for repairing finger soft tissue with bone defect. METHODS: Thirty-three patients with finger soft tissue or bone defect were treated from December 2014 to October 2016, including 24 males and 9 females aged from 21 to 52 years old with an average of (36.42±5.70) years old, and soft tissue defect area ranged from 1.3 cm×1.8 cm to 2.3 cm×4.2 cm. According to damage degree, nature and patients' options, 15 finger of 15 cases were adopted retrograde dorsal metacarpal artery perforators fascia flap, 10 fingers of 9 cases were treated with free foot artery descending branch wrist skin flap, 9 fingers of 9 cases were treated with free the second toe details phalanges compound flap. Survival rate, postoperative complications and finger function assessed by Dargan functional criteria at the latest follow up were observed. RESULTS: All flaps were survived, both of donor site and recipient site were without deep infected. The donor site of one patient occurred necrotic, and the distal donor site of one patient occurred surface necrotic, then healed by active dressing change. All patients were followed up from 6 to 16 months with an average of(8.34±1.28) months. Two points of finger recognition were restored between 8 and 12 mm with an average of (8.84±0.43) mm, and the appearance, texture and sensory functions of skin flap were restored. No obvious complications were observed on the donor site. According to Dargan function evaluation of finger joints, 18 patients got excellent results, 14 moderate and 1 good. CONCLUSIONS: Three kinds of mini skin flap could receive good results in repairing soft tissue of finger or bone defect. Reverse dorsal metacarpal artery perforator fascia flap is not necessary with anastomosing blood vessels and has advantages of safe, simple and high survival rate. Descending branch of superior cutaneous branch of free ulnar artery could cut multiple other perforator flaps simultaneously, and the scar is small and hidden. Dissociated the second toe combined metatarsal phalangeal flap could repair shape and function of finger to the maximum extent and donor site is hidden.

4-Phenylbutyric acid presents therapeutic effect on osteoarthritis via inhibiting cell apoptosis and inflammatory response induced by endoplasmic reticulum stress.

Osteoarthritis (OA) is a common bone and joint disease with a wild range of risk factors, which is associated with endoplasmic reticulum (ER) stress. The aim of our study was to discuss the possible mechanism of ER stress associated with OA in vivo and explore novel therapeutic method against OA. OA-induced damages in cartilage tissues were evaluated by HE, Safranin O/fast green, and TUNEL staining. The inflammatory factors concentration and the expression of FAP, MMP2, MMP9, Bax, Bcl-2, CHOP, and GRP78 were evaluated by ELISA, real-time PCR, and Western blot analyses. As results, 4-phenylbutyric acid (4-PBA)-treated OA cartilage tissues presented alleviated tissue damage with less apoptotic cells and cytokine production in comparison with advanced-OA tissues. Downregulation of Bax/Bcl-2, CHOP, GRP78, inflammatory factors, and reactive oxygen species generation, and the increase of MMP level detected after 4-PBA treatment indicated an inhibitory effect of 4-PBA on cell apoptosis, inflammatory response, and ER stress in OA. In conclusion, we indicate that ER stress causes cell apoptosis and inflammatory response, resulting in the tissue damage within OA. At the same time, 4-PBA exhibited protective effect on cartilage cells against OA through the inhibition of ER stress.

ß­Ecdysterone promotes autophagy and inhibits apoptosis in osteoporotic rats.

Osteoporosis is an aging process of skeletal tissues with characteristics of reductions in bone mass and microarchitectural deterioration of bone tissue. The present study aimed to investigate the effects of glucocorticoid­induced osteoporosis on osteoblasts and to examine the roles of ß­ecdysterone (ß­Ecd) involved. In the present study, an in vivo model of osteoporosis was established through the subcutaneous implantation of prednisolone (PRED) into Sprague­Dawley rats, with or without a subcutaneous injection of ß­Ecd (5 or 10 mg/kg body weight). Expression of Beclin­1 and microtubule­associated protein 1A/1B­light chain 3I/II and apoptosis in lumbar vertebrae tissues was measured by immunofluorescence and TUNEL assays, respectively. Serum concentration of calcium and phosphorus, and the activity of tartrate­resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) were measured by biochemical assay. Reverse transcription­quantitative polymerase chain reaction and western blotting was used for detect the expression of related genes and proteins. PRED treatment inhibited bone formation by decreasing bone mineral density, and suppressing the expression of Runt­related transcription factor 2 and bone morphogenetic protein 2, while enhancing the activity of alkaline phosphatase, upregulating the expression of receptor activator of nuclear factor-κB ligand, and increasing the serum content of calcium, phosphorus and tartrate­resistant acid phosphatase in rats. Additionally, PRED was revealed to inhibit autophagy through the downregulation of Beclin­1, autophagy protein 5 and microtubule­associated protein 1A/1B­light chain 3I/II expression, whereas it induced the apoptosis, through the activation of caspase­3 and the suppression of apoptosis regulator BCL2 expression. Notably, the PRED­induced alterations in bone formation, autophagy and apoptosis were revealed to be attenuated by ß­Ecd administration. In conclusion, the findings of the present study suggested that ß­Ecd may be a promising candidate for the development of therapeutic strategies for the treatment of osteoporosis, through the induction of autophagy and the inhibition of apoptosis in vivo.

Effect of ß­ecdysterone on glucocorticoid­induced apoptosis and autophagy in osteoblasts.

The aim of the present study was to investigate the effect of glucocorticoids in osteoblasts and to examine the role of ß­ecdysterone in the pathogenesis of glucocorticoid­induced osteoporosis. Osteoblasts were induced from bone marrow mesenchymal stem cells, which were isolated from C57BL/6 mice. Cell viability and apoptosis of osteoblasts were measured by Cell Counting Kit­8 and flow cytometry analysis, respectively. The expression of related genes and proteins was measured by reverse transcription quantitative polymerase chain reaction and western blot analysis respectively. Dose­dependent decreases in the cell proliferation and differentiation were observed in dexamethasone (Dex)­treated osteoblasts, evidenced by downregulation in the activity of alkaline phosphatasedecreased expression levels of Runt­related transcription factor 2 and osteocalcin, and upregulated expression of RANK ligand. Dex also induced apoptosis and inhibited autophagy of osteoblasts, evidenced by upregulated B­cell lymphoma 2 (Bcl­2)­associated X protein/Bcl­2 ratio and the activation of mammalian target of rapamycin (mTOR), and decreased expression levels of Beclin­1, autophagy protein 5 and microtubule­associated protein 1 light chain 3 II. The effects on cell proliferation, apoptosis and autophagy induced by Dex were reversed by ß­ecdysterone in a dose­dependent manner. Therefore, ß­ecdysterone may be a promising candidate drug for the treatment of osteoporosis through inducing osteoblast autophagic activity by inactivating mTOR.

Amniotic membrane-derived stem cells help repair osteochondral defect in a weight-bearing area in rabbits.

Our study evaluated the use of amniotic membrane-derived stem cells for repairing osteochondral defects in a weight-bearing area in rabbits. Twenty-four 3-month-old male or female New Zealand white rabbits were selected. The rabbits were randomly divided into 3 groups of eight, according to the treatment received for an experimentally inflicted femoral medial malleolus lesion, group I received a human acellular amniotic membrane seeded with bone marrow-derived mesenchymal stem cells (HAAM-BMSCs) implant; group II received a simple HAAM implant and the control group received no experimental lesion or treatment. The rabbits were sacrificed at 12 and 24 weeks after the procedures (4 rabbits in each time-point) and the cartilage repair status in each animal was evaluated under the microscope. The tissue of the HAAM-BMSCs group grew well covering an area in the visual field that was significantly larger than that of the HAAM group (p<0.05). The percentage of collagen II-positive area in the HAAM-BMSC group was significantly higher than that in HAAM group (p<0.05). The number of chondrocytes determined by toluidine blue staining was higher in the HAAM-BMSC group than that in the HAAM group (p<0.05). The Wakitani scores of the HAAM and HAAM-BMSC groups were significantly higher (worse) than those of the normal control group (p<0.05), but the score in the HAAM-BMSC group was significantly lower than that in the HAAM group (p<0.05). The Wakitani scores in the HAAM-BMSC group were not different between the two time-points taken. Based on our findings, the amniotic membrane-derived stem cells had a good therapeutic effect in repairing the osteochondral defects in the weight-bearing area, and the number of chondrocytes in the injured area was increased significantly, which accelerated the repair of the damaged tissue in rabbits.

Local influence of high molecular polyethylene particles on heterotopic ossification.

We studied the effect of molecular polyethylene particles on local heterotopic ossification. A total of 36 healthy Sprague-Dawley rats were randomly divided into the control group (n=18) and the observation group (n=18). High molecular polyethylene particles were injected to rupture Achilles tendon position in the observation group, and normal saline was injected in the control group. X-ray examinations were conducted on Achilles tendon in the 4th, 8th and 12th week after operation. The incidence rate of heterotopic ossification was evaluated, and bone trabecula morphological structure was studied under optical microscope after hematoxylin and eosin staining. Bone morphogenetic protein 2 (BMP-2), transforming growth factor-ß (TGF-ß), interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), runt-related transcription factor 2 (Runx2) and matrix metalloproteinase-9 (MMP-9) expression levels were also measured. Our results showed that heterotopic ossification incidence in the observation group was significantly lower than that in the control group. Achilles tendon structure in the control group increased in volume, and its texture was harder and cartilage-like. In the observation group, trabecular bone volume, thickness and quantity were more than those observed in the control group. BMP-2, TGF-ß, IL-1, TNF-α, Runx2 and MMP-9 levels in the observation group were significantly lower than those in the control group. We concluded that, high molecular polyethylene particles had a significant inhibiting effect on local heterotopic ossification.

[Surgical treatment of grade III pronation-external rotation fractures of ankle].

Objective: To summarize the short-term effectiveness of the surgical treatment for grade III pronation-external rotation ankle fractures. Methods: Between October 2011 and May 2015, 36 patients with pronation-external rotation ankle fractures (grade III) were treated with internal fixation and repair of the anterior lower tibiofibular ligament, including 21 males and 15 females with an average age of 45.2 years (range, 21-72 years). Injury was caused by sprain in 19 cases, by traffic accident in 6 cases, and by falling from height in 11 cases. All patients had closed fractures, with no blood vessel and nerve injury. The locations were the left ankle in 13 cases and the right ankle in 23 cases. The time from injury to operation was 3 to 10 days (mean, 6.5 days). At last follow-up, ankle function was evaluated by American Orthopaedic Foot and Ankle Society (AOFAS) ankle-foot score, and the improvement of pain was evaluated by visual analogue scale (VAS). Results: Primary healing of incision was obtained in all patients, no incision infection and skin necrosis occurred. Twenty-eight patients were followed up 12-36 months (mean, 17.5 months). X-ray films showed bone union was achieved within 2.6-5 months (mean, 3.2 months). No fracture of internal fixation and disruption of tibiofibular diastasis occurred. At last follow-up, according to AOFAS score for ankle function evaluation, the pain score was 36.3±2.9, the function score was 44.3±3.2, the ligament condition score was 9.2±0.5, and the total score was 89.8±6.6; the results were excellent in 11 cases, good in 15 cases, and fair in 2 cases. VAS score was 1.6±0.5. The range of motion of the ankle was (13±5)° in dorsiflexion and (38±9)° in planteroflexion. Conclusion: Repair of anterior tibial ligament is an effective method to treat tibiofibular diastasis injury in the surgical treatment of grade III pronation-external rotation ankle fractures, with convenient operation, and satisfactory short-term effectiveness.

[Surgical treatment for open tarsometatarsal joint injury].

OBJECTIVE: To discuss the surgical method and clinical efficacy for open tarsometatarsal joint injuries. METHODS: From March 2011 to January 2015, 21 patients with open tarsometatarsal joint injuries were treated with stage-surgery method, including 14 males and 7 females with an average age of 45.6 years old ranging from 20 to 75 years. Injury site occurred in the left foot of 13 cases and right foot of 8 cases. Traffic injury was in 5 cases, crush injury in 6 cases, heavy crushing was in 10 cases. According to Myerson to classify for tarsometatarsal joint injury, 5 cases were type B2, 9 cases were type C1, and 7 cases were type C2. And according to Gustilo to typing for soft tissue injury, 5 cases were type IIB, 10 cases were type IIIA, 6 cases were type IIIB. Fracture healingand complications were observed after operation and clinical effects were evaluated according to the midfoot score of AOFAS. RESULTS: All the patients were followed up from 11 to 40 months with an average of 16.2 months. The fracture healing time was from 10 to 16 weeks with an average of 12.3 weeks. No complications such as deep infection, nonunion and osteomyelitis were found. Midfoot score of AOFAS at last follow-up was 83.0±14.9, 9 cases got excellent results, 8 good, 2 fair, 2 poor. Two patients complicated with severe traumatic arthritis once again underwent tarsometatarsal arthrodesis. CONCLUSIONS: For the treatment of open tarsometatarsal joint injury, reasonable debridement, comprehensive assessment for the soft tissue injury, correctly grasp the surgical indications and time of internal fixation, can reduce the incidence of deep infection and osteomyelitis.

Mechanisms underlying the antiapoptotic and anti-inflammatory effects of monotropein in hydrogen peroxide-treated osteoblasts.

Monotropein, the primary iridoid glycoside isolated from Morindacitrifolia, has been previously reported to possess potent antioxidant and antiosteoporotic properties. However, there is no direct evidence correlating the antiosteoporotic effect of monotropein with its observed antioxidant capacity, and the molecular mechanisms involved in mediating these processes remain unclear. Therefore, the aim of the present study was to investigate the protective effects of monotropein against oxidative stress in osteoblasts and the mechanisms involved in mediating this process. Osteoblast viability was evaluated using the MTT assay. The mitochondrial membrane potential and reactive oxygen species were detected by flow cytometry analyses. Western blotting and enzyme­linked immunosorbent assays were performed to detect protein expression levels. A significant reduction in osteoblast viability was observed at 24 h following exposure to various concentrations (100­1,000 µM) of H2O2 compared with untreated osteoblasts. The cytotoxic effect of H2O2 was notably reversed when osteoblasts were pretreated with 1­10 µg/ml monotropein. Pretreatment with 1-10 µg/ml monotropein increased the mitochondrial membrane potential and reduced the generation of reactive oxygen species in osteoblasts following exposure to H2O2. In addition, the H2O2­induced increase in apoptotic markers (caspase-3 and caspase-9) and H2O2-induced reduction in sirtuin 1 levels were significantly reversed following pretreatment of cells with monotropein. Furthermore, monotropein significantly reduced H2O2­induced stimulation of NF­κB expression, in addition to the expression of a number of proinflammatory mediators. These results indicate that monotropein suppresses apoptosis and the inflammatory response in H2O2­induced osteoblasts through the activation of the mitochondrial apoptotic signaling pathway and inhibition of the NF­κB signaling pathway.

[Iindividual choice of distal fibula internal fixation for ankle fractures in elderly].

OBJECTIVE: To explore individual choice and therapeutic effect of distal fibula internal fixation in treating ankle fractures in elderly. METHODS: From May 2012 to April 2015, 68 elderly patients with ankle fractures were treated by surgical operation, included 37 males and 31 females with an average of 69.2 years old ranging from 62 to 81 years. According to Danis-Weber classification, there were 19 cases belong to type A, 31 cases belong to type B, and 18 cases belong to type C. According to Lange-Hanson classification, 22 cases were supinatio-extorsion, 18 were pronate-extorsion, 19 were supinatio-adduction, and 9 were pronate-abduction. All patients were performed individyually with different internal fixation methods for the treatment of distal fibula fracture according to different types of fracture. Clinical results were evaluated based on clinical examination, radiographic evaluation and AOFAS score. RESULTS: Twelve patients were treated with Herbert screw, 7 cases with Kirschner wire tension band, 5 cases with 1/3 tube plate, 6 cases with reconstruction plate, 17 cases with fibular end dissection steel plate composite, and 21 cases with distal fibula anatomic locking plate. All patients were followed up from 12 to 26 months with an average of 17.7 months. The operative incision of all patients were primary healed. And there was no bone nonunion, ankle instability, internal fixation loosening and fracture occurred. Fracture healing time ranged from 2.7 to 4 months with an average of 3.2 months, and had significant differences among different groups(P<0.05). There were no statistical differences in AOFAS score, VAS score and motion of ankle joint among different internal fixation groups(P>0.05). Dorsal stretch was 6° to 18° with an average of 15°, plantar flexion ranged from 26°to 47° with an average of 37°. AOFAS score at the latest following-up was 88.4±4.3, 34 patients got an excellent result, 30 good and 4 fair. CONCLUSIONS: Good clinical results could be obtained by using individualized internal fixation for distal fibula fracture for the treatment of the ankle fractures in elderly.

4­Phenylbutyrate protects rat skin flaps against ischemia­reperfusion injury and apoptosis by inhibiting endoplasmic reticulum stress.

4­phenylbutyrate (4­PBA) is a low molecular weight fatty acid, which has been demonstrated to regulate endoplasmic reticulum (ER) stress. ER stress­induced cell apoptosis has an important role in skin flap ischemia; however, a pharmacological approach for treating ischemia­induced ER dysfunction has yet to be reported. In the present study, the effects of 4­PBA­induced ER stress inhibition on ischemia­reperfusion injury were investigated in the skin flap of rats, and transcriptional regulation was examined. 4­PBA attenuated ischemia­reperfusion injury and inhibited cell apoptosis in the skin flap. Furthermore, 4­PBA reversed the increased expression levels of two ER stress markers: CCAAT/enhancer-binding protein­homologous protein and glucose­regulated protein 78. These results suggested that 4­PBA was able to protect rat skin flaps against ischemia­reperfusion injury and apoptosis by inhibiting ER stress marker expression and ER stress­mediated apoptosis. The beneficial effects of 4­PBA may prove useful in the treatment of skin flap ischemia­reperfusion injury.