BACKGROUND:Through compounding hydroxyapatite and poly-DL-lactide, the mechanical properties, physical and chemical properties of the implants can be enhanced.
OBJECTIVE:To detect the effect of hydroxyapatite/poly-DL-lactide composite internal fixation screws in canine femoral condyle cancel ous bone fracture repair.
METHODS:Forty-two beagle dogs were operated to bilateral femoral condyle fracture models. The left side was fixed using hydroxyapatite/poly-DL-lactide screws as experimental group;while the right side was fixed with pure poly-DL-lactide screws as control group. After 2, 4, 8, 12, 24, 36 and 48 weeks, conditions of fracture were observed using X-ray, femoral and screw specimens were observed histopathological y, and the bending strength and the average molecular weight were detected. The biological absorption rate, intensity decay rate and biodegradation rate were calculated.
RESULTS AND CONCLUSION:After 2-48 weeks, bilateral fractures were fixed wel and new bone grew wel , but the biological absorption rate of the screws in the experimental group was lower than that in the control group (P ≤0.01). In the first 2, 4 weeks, the bending strength of the experimental screws was higher than that of the control screw (P ≤0.05), but the biodegradable speed was slower in the former one (P ≤ 0.05 or P ≤ 0.01). The pathological changes were similar in the two groups. After 48 weeks, the fractures were healed and bone tissue reconstruction was completed. Compared with the pure poly-DL-lactide screws, the hydroxyapatite/poly-DL-lactide composite internal fixation screws have better fixation effects, biocompatibility, mechanical properties and biodegradability.

This study aimed to explore the mechanism of volatile oil from purslane in treating itch induced by eczema through establishing the itch model,stimulating the keratinocyte with capsaicine (CAP).SD rats were divided into the control group,the model group,the high dose group of volatile oil from purslane,and low dose group of volatile oil from purslane.After finishing the experiment,the morphology of keratinocytes was observed by immunofluorescence technique,while Ca2+ concentration was detected by flow cytometry,and the contents of leukotriene A4 methyl ester (LTA4),interleukin-31 (IL-31) and hydroxy trptamine H1 (HTH1) were quantified by ELISA assay.The expression of TRPV1 mRNA in keratinocytes was tested by RT-PCR,while the protein level of TRPV1 was quantified by western blot.Compared with the model group,it was found that the cell count of positive keratinocytes,the Ca2+ concentration,the levels of LTA4,IL-31 and HTH1,and the mRNA and protein expressions of TRPV1 in the high dose and low dose groups were significantly decreased (P ＜ 0.05).In conclusion,it was demonstrated that the volatile oil from purslane may relieve itch through inhibiting the activation of TRPV1 and reducing secondary inflammatory reaction.

BACKGROUND: It has been reported that type 1 diabetes mellitus can result in impairments of bone regeneration and repair, and local injection of fibroblastic growth factor-2 (FGF-2) can obviously promote fracture healing, but its effect on type 2 diabetes mellitus is still unclear.OBJECTIVE: To observe the effects of recombinant human fibroblastic growth factor-2 (rhFGF-2) combined with soluble tumor necrosis factor receptor-1 (sTNF-R1) on impaired bone regeneration and repair in type 2 diabetes mellitus.DESTGN: A randomized controlled trial.SETTING: Department of Orthopaedics, the Third Xiangya Hospital of Central South University.MATERIALS: Twenty male Zucker diabetic fatty rats (ZDF/Gemi-fa/fa), 10 weeks of age, were purchased from Charles River Laboratory. rhFGF-2 was obtained from Orquest Incorporation; sTNF-R1 protein (PEG-r-metHu-sTNF-R1) was provided by Amgen Incorporation.METHODS: This experiment was finished in the central lab of the Third Xiangya Hospital of Central South University from September to November in 2006. ①Grouping: The 20 rats were randomly assigned into treated group (n =10)and control group (n =10). ② Experimental methods: All rats were examined for body mass, blood glucose, glycosuria and glycosemia. One week later, all the rats underwent the standard DO protocol, including placement of the external fixators and osteotomies to the left tibia. Distraction was initiated in the following morning (one day latency) at 0.2 mm b.I.d. (0.4 mm per day) and continued for 14 days. During surgery, all the rats received an injection of either rhFGF-2(25 mg/kg) for the treated group, or physiological saline (25 mg/kg) for the control group, into the hematoma of the osteotomic gap. The sTNF-R1 (8 mg/kg) or the same. Amount of saline was subcutaneously injected into the treated and control rats respectively every other day for 14 days. Evaluation: The serum biochemical indexes, amount of bone formation and number of proliferative cells in the distraction gaps were determined.MAIN OUTCOME MEASURES: Biochemical indexes, amount of bone formation and number of proliferative cells in the distraction gaps.RESULTS: All the 20 rats were involved in the final analysis of results. ①The blood glucose, glucosuria, ketonuria,serum levels of insulin and osteocalcin were not obviously different between the treated group and control group (P ＞0.05). ② The area and density of mineralization of the distraction gaps, and the endosteal and peristeal new bone formation in the treated group were all obviously higher than those in the control group (P ＜ 0.05-0.01). The number and percentage of the positive cells of proliferating cell nuclear antigen (PCNA) in the distraction gaps were obviously higher in the treated group than in the control group (P ＜ 0.05-0.01).CONCLUSION: The local application of rhFGF-2 combined with sTNF-R1 can enhance bone formation by increasing the proliferation during distraction osteogenesis in ZDF rats. The combination of rhFGF-2 and sTNF-R1 may be an effective treatment for type 2 diabetic patients with fracture healing problem.

The author proposed student-centered learning system in otolaryngology-head and neck surgery for undergraduate clinical training after exploration and intentions.Four mutual impacted frames were built including integration of teaching philosophy,visualization of training methods,diversification of educational targets and interaction of training courses.Endoscopic navigated learning and multimedia aided training were applied,respective teaching purposes were set and various clinical training courses were introduced to students in their learning of otolaryngology,which were believed to help develop more medical talents with higher comprehensive qualities and better clinical skills.

Objective To explore the effect of osthole on mast cells and expression of STAT5 gene and protein in them. Methods Passive cutaneous anaphylaxis was made in mice to copy eczema model, then the allergic mast cells were separated, and the ovalbumin was used to induce allergy of mast cells. Different concentrations of osthole were used to intervene the sensitized mast cells.Then the sensitized mast cells were divided into blank control group, osthole high-dose group and low-dose group.At the end of the experiment, morphology of the mast cells was detected by immunofluorescence technology.MTT assay was used to detect the influence of drugs on mast cells proliferation. RT-PCR and Western blotting were used to detect the expression of STAT5 gene and protein. Results As compared with blank control group, the number of mast cells in the osthole groups was significantly reduced, cells and nuclei obviously shrank, even apoptosis of some cells could be observed; the inhibition rate of mast cells in osthole groups was significantly increased in concentration-dependent manner ( P<0. 01 ) . As compared with blank control group (2.16±0.57), gene expression of STAT5 was significantly decreased in osthole high-dose group (0.59±0.12) and low-dose group (0.82±0.13) (P<0.01).The protein expression of STAT5 was also significantly decreased in osthole high-dose group and low-dose group as compared with blank control group (P<0.01). Conclusion Osthole can inhibit the proliferation of sensitized mast cells, and reduce the expression of STAT5 gene and protein.

OBJECTIVETo explore the action mechanism of electroacupuncture (EA) at "Shenmen" (HT 7) and "Sanyinjiao" (SP 6) on insomnia.

METHODSThirty SD rats were randomly divided into a blank group, a model group and an EA group, 10 cases in each group. The insomnia model was made by immobilization method in the model group and EA group. After model establishment, rats in the blank group and model group were treated with fixation and no treatment was given. Rats in the EA group were treated with EA at "Shenmen" (HT 7) and "San-yinjiao" (SP 6) for 15 min, once a day for 4 days. After treatment, the level of daytime and nighttime activity, open-arm entry percentage and open-arm time percentage of elevated plus-maze test were measured; the content of noradrenaline (NE), dopamine (DA) and epinephrine (EPI) in plasma and NE, DA in thalamus and brainstem were detected by using euzymelinked immunosorbent assay method.

RESULTSCompared with the blank group, the daytime activity was increased and nighttime activity was reduced in the model group (both P<0. 05); the open-arm entry percentage and open-arm time percentage of elevated plus-maze test were both reduced in the model group (both P<0. 05); the contents of NE, DA, EPI in the plasma and NE, DA in thalamus and brainstem were increased in the model group (all P<0. 05). Compared with the model group, the daytime activity was reduced and nighttime activity was increased in the EA group (both P<0. 05); the open-arm entry percentage and open-arm time percentage of elevated plus-maze test were both increased in the EA group (both P<0. 05); the contents of NE, DA, EPI in the plasma and NE, DA in thalamus and brainstem were reduced in the EA group (all P< 0. 05).

CONCLUSIONElectroacupuncture at "Shenmen" (HT 7) and "Sanyinjiao" (SP 6) can restrain the over-activity of the sympathetic-adrenal medullary system to treat the insomnia.

Acupuncture Points ; Adrenal Medulla ; metabolism ; Animals ; Anxiety ; Disease Models, Animal ; Dopamine ; metabolism ; Electroacupuncture ; Female ; Humans ; Male ; Norepinephrine ; metabolism ; Rats ; Rats, Sprague-Dawley ; Sleep Initiation and Maintenance Disorders ; metabolism ; physiopathology ; psychology ; therapy ; Sympathetic Nervous System ; physiopathology

ObjectiveTo verify the reliability of the mouse model of cerebral cortical microinfarct induced by two-photon microscopy and to explore its pathological changes.MethodsSeventeen male C57BL/6J mice were randomly divided into a microinfarct group (n=11) or a sham operation group (n=6).A thinned cranial window of 3 mm diameter was performed over the cerebral cortex with a high-speed micro-drill until the small blood vessels were clearly observed under a dissecting microscope.Then, a permanent single cortical penetrating arteriole occlusion was induced with a gradually enhanced ultrashort laser irradiation through the thinned cranial window with two-photon microscopy.At 7 days after modeling, the cerebral microinfarct volume was measured with HE staining, and the neuron loss, activation of glial cells and deposition of 3-nitrotyrosine were assessed using immunohistochemistry.ResultsThe target vessels of cerebral cortex in 8 (72.7%) mice were occluded and the microinfarcts formed in the microinfarct group, and the average microinfarct volume was 317.23±20.29 μm3.There were remarkable neuron loss and microglia infiltration in the infarcted core, a large number of reactive astrocytes surrounding the infarcted lesion, and massive deposition of 3-nitrotyrosine in the peri-infarct area.No infarcts were observed in the sham operation group.The deposition of 3-nitrotyrosine in the sham operation group was significantly less than that in the microinfarct group (8.00±1.48 vs.98.38±9.10;t=23.962, P<0.001).Conclusions The mouse model of cerebral cortical microinfarct induced by two-photon microscopy is reliable, and its histopathologic changes are consistent with the pathologic features of cerebral microinfarct.

Objective To investigate the protective effect of Gui Zhi Fuling Jiaonang on endurance to ischemia and hypoxia .Methods Mice were randomized into four groups :control group ,positive drug control group ,Gui Zhi Fuling Jiaonang high‐dose group (0 .93 g/kg) ,and Gui Zhi Fuling Jiaonang low‐dose group (0 .465 g/kg) . All mice were treated with corresponding drugs for 7 days .The hypoxia mice model was established through hypoxia in the closed jars , cerebral anoxia by decapitation , poisoning with sodium nitrite and isoprenaline . Then the hypoxia‐ischemia rat model was established by injecting isoproterenol . The anti‐hypoxic effects were observed . Results Compared with control group ,Gui Zhi Fuling Jiaonang high‐dose group (0 .93 g/kg) had a tendency to extend the survival time of mice model established through hypoxia in the closed jars ;Gui Zhi Fuling Jiaonang high‐dose (0 .93 g/kg) and low‐dose (0 .465 g/kg) groups had a tendency to extend the survival time of mice model established through cerebral anoxia by decapitation (P>0 .05) .Compared with that in control group ,the survival time of mice in Gui Zhi Fuling Jiaonang low‐dose group under poisoning with sodium nitrite and Gui Zhi Fuling Jiaonang high‐dose group under poisoning with isoprenaline were significantly prolonged .Besides ,Gui Zhi Fuling Jiaonang relieved myocardial tissue damage caused by ischemia and hypoxia ( P< 0 .05 ) .Conclusion Gui Zhi Fuling Jiaonang has an obviously protective effect on isoprenaline‐induced hypoxia and myocardial ischemia .

Objective To observe the neurotoxicity of epidural different dose of dexmedetomi-dine in combination with 0.75% bupivacaine.Methods Twenty-five rabbits weight 2-3 kg without gender tendency and equipped with an epidural lumbar catheter were allocated randomly to five groups with 5 cases each.The control group (group C)received injections of 1.5 ml normal saline,0.75%bupivacaine 1.5 ml plus normal saline 0.5 ml in group B,and the other treatment groups received in-jections of 0.75% bupivacaine 1 ml plus dexmedetomidine 0.1 μg/kg (group D1 ), 0.75%bupivacaine 1 ml plus dexmedetomidine 0.2 μg/kg (group D2 )or 0.75% bupivacaine 1 ml plus dexmedetomidine 0.4 μg/kg (group D3),in the same volume of 1.5 ml.After successive 3-day epi-dural administration of the drugs and a 3-day observation,the rabbits were killed and the spinal cord was examined under optical and electron microscope.Results Serious damages of neuron were found in 1 animal from group D2 and 2 from group D3 under optical microscope.There was unclear bounda-ries between gray and white matter.Some nerve cells appeared necrosis in the grey matter of spinal cord and the number of nerve cells was decreased.Some reversible changes were found in all groups under electron microscope.Conclusion Epidural administration of dexmedetomidine can induce spinal cord and spinal nerves injury dose-dependently,and the motor function can recuperated completely.

Objective To explore the neuroprotective effect of cyclosporine A against cerebral ischemia in a rat model of cerebral ischemia reperfusion. Methods Fifty-two adult male SD rats, weighted 250-280 gram, were randomly divided into three groups: the sham group (group A, n=6), PBS control group (group B, n=23) and cyclosporine A group (group C, n=23). Group C received hypodermic injection of cyclosporine A 10mg/kg daily after surgery and group B re?ceived equal volume of PBS instead. Modified Neurological Severity(mNss)scores were used to assess the neurological deficits at 3, 7, 14, 21 and 30 days following cerebral ischemia. The infarct volume were measured 3 days after reperfu?sion. The neurons, reactive microglia and astrocytes around the infract area were detected by immunofluorescence at 3 and 30 days after surgery. Results Modified Neurological Severity scores were significantly lower in group C than group B at the third(P=0.003),seventh (P=0.011),Fourteenth (P=0.000),twenty-first (P=0.003) and thirtieth (P=0.004) days after surgery. cyclosporine A reduced infarct volume, reactive microglia and astrocytes while increased survived neurons (P<0.001) in ischemic penumbra 3 and 30 days after reperfusion (all P<0.001). Conclusion Continuous injection of cyclosporine A not only protects neurons against ischemia damage but also improves neurological functional recovery af?ter acute stage of damage, possibly through reduction of reactive microglia cells and proliferation of astrocytes.