Ibutilide decreases defibrillation threshold by the reduction of activation pattern complexity during ventricular fibrillation in canine hearts

Background  Ibutilide has been commonly used for pharmacologic cardioversion of atrial fibrillation and flutter in clinical settings The objective of this study was to investigate the effects of ibutilide on the defibrillation threshold (DFT), restitution properties, dispersion of refractoriness and activation patterns during ventricular fibrillation (VF).

Methods  Ibutilide was administrated intravenously in six open-chest beagles. Before and after the drug administration, 20-second episodes of VF were electrically induced and recorded with a 10×10 unipolar electrode plaque sutured on the lateral epicardium of the left ventricle. DFT and VF activation patterns, including type of epicardial activation maps, VF cycle length (VF-CL), conduction velocity, wavelength (WL) and reentry incidence, were measured. Restitution properties and dispersion of refractoriness were estimated from activation recovery intervals (ARI) during pacing.

Results  Compared to baseline, ibutilide markedly decreased the DFT by 31% ((491±14) V vs. (337±59) V, P<0.01). The drug significantly reduced the maximal slope of the restitution curve (1.34±0.08 vs. 0.76±0.06, P<0.01) and its epicardial dispersion (0.36±0.09 vs. 0.21±0.06, coefficient of variation, P=0.03). The dispersion of refractoriness was enhanced at the pacing cycle length of 300 ms to 160 ms by ibutilide. The drug significantly increased the VF-CL ((96±19) ms vs. (112±20) ms, P<0.01) and the WL ((41±9) mm vs. (52±14) mm, P=0.02) during VF, and reduced the reentry incidence by 25% (0.08±0.02 vs. 0.06±0.02, P<0.01). In the epicardial activation maps, ibutilide significantly reduced the percentage of more complex activation maps during VF.

Conclusions  Intravenous ibutilide significantly decreased the DFT. It might be due to reduction of activation pattern complexity during VF.

     

Clinical evaluation of remineralization potential of casein phosphopeptide amorphous calcium phosphate nanocomplexes for enamel decalcification in orthodontics

are the focus of intense research. The aim of this study was to evaluate the remineralizing effect of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) nanocomplexes on enamel decalcification in orthodontics.

Methods  Twenty orthodontic patients with decalcified enamel lesions during fixed orthodontic therapy were recruited to this study as test group and twenty orthodontic patients with the similar condition as control group. GC Tooth Mousse, the main component of which is CPP-ACP, was used by each patient of test group every night after tooth-brushing for six months. For control group, each patient was asked to brush teeth with toothpaste containing 1100 parts per million (ppm) of fluoride twice a day. Standardized intraoral images were taken for all patients and the extent of enamel decalcification was evaluated before and after treatment over this study period. Measurements were statistically compared by t test.

Results  After using CPP-ACP for six months, the enamel decalcification index (EDI) of all patients had decreased; the mean EDI before using CPP-ACP was 0.191±0.025 and that after using CPP-ACP was 0.183±0.023, the difference was significant (t=5.169, P <0.01). For control group, the mean EDI before treatment was 0.188±0.037 and that after treatment was 0.187±0.046, the difference was not significant (t=1.711, P >0.05).

Conclusion  CPP-ACP can effectively improve the demineralized enamel lesions during orthodontic treatment, so it has some remineralization potential for enamel decalcification in orthodontics.

     

Expectant management of heterotopic cesarean scar pregnancy

Background  Heterotopic cesarean scar pregnancy (HCSP) is a very rare but life-threatening entity and there is no optimal management strategy. Here we report a successfully managed case of HCSP with expectant treatment in a tertiary referral hospital.

Methods  A woman with HCSP after in vitro fertilization-embryo transfer opted for expectant treatment after five days of mild bleeding and ultrasound demonstrated cardiac activity disappearance of the scar pregnancy at 8⁺⁴ weeks of gestation.

Results  The patient had mild to moderate bleeding during close monitoring. Three days later, speculum examination revealed the gestational mass was partly protruding at the os of the cervix and it was removed with forceps without massive hemorrhage. A healthy male baby was delivered by cesarean section at gestational age of 36⁺⁴ weeks.

Conclusions  The expectant method might be an alternative option for a HCSP with loss of cardiac activity of the scar pregnancy, when applied under supportive management and with available emergency surgery facilities.

     

Decreased hepatic glucose production in obese rats by dipeptidyl peptidase-IV inhibitor sitagliptin

Background  Dipeptidyl peptidase-IV (DPP-4) inhibitors are now used to improve postprandial glycemic control in type 2 diabetes. However, their effects on hepatic glucose production (HGP) in obesity are not clear. This study was designed to test the hypothesis that gluconeogenesis and HGP can be modulated by DPP-4 inhibitors in obesity.

Methods  Sprague Dawley male rats were divided into four groups, each on a different diet: general rat chow, n=10 (G); G+sitagliptin, n=10; high fat chow (obesity), n=10 (55% fat calories, HFO); HFO+sitagliptin, n=10. After 10 weeks, the rats were fasted overnight and glucose metabolism was determined using 3-³H-glucose and ¹⁴C-glycerol as tracers.

Results  Glycerol rate of appearance (P <0.00001), plasma glycerol (P <0.05) and free fatty acid (FFA) (P <0.05) concentrations, and HGP (P <0.05) were decreased in HFO+sitagliptin group compared with HFO group, but there was no significant difference between G and G+sitagliptin groups (P >0.05). Gluconeogenesis in HFO group was five times of that in G rats (P <0.01), but was significantly declined in HFO+sitagliptin group (P <0.0001).

Conclusions  Gluconeogenesis and HGP were inhibited by sitagliptin in high fat-induced obese rats due to decreased glycerol availability, which was a result of reduced glycerol release from adipose tissues. The finding suggests that sitagliptin is potentially useful for controlling fasting glucose in obesity, thereby delaying or preventing the development of diabetes.

     

Characteristic gene expression profiles in the progression from normal gastric epithelial cells to moderate gastric epithelial dysplasia and to gastric cancer

Background  Gastric cancer ranks high among the most common causes of cancer-related death worldwide. This study was designed to explore key genes involved in the progression of normal gastric epithelial cells to moderate gastric epithelial dysplasia (mGED) and to gastric cancer.

Methods  Twelve pairs of mGED tissues, gastric cancer tissues, and normal gastric tissues were collected by gastroscopy. Total RNA was then extracted and purified. After the addition of fluorescent tags, hybridization was carried out on a Gene chip microarray slide. Significance analysis of microarrays was performed to determine significant differences in gene expression between the different tissue types.

Results  Microarray data analysis revealed totally 34 genes that were expressed differently: 18 highly expressed (fold change >2; P <0.01) and 16 down-regulated (fold change >2; P <0.01). Of the 34 genes, 24 belonged to several different functional categories such as structural molecule activity, extracellular regions, structural formation, cell death, biological adhesion, developmental processes, locomotion, and biological regulation that were associated with cancer. The remaining 10 genes were not involved in cancer research. Of these genes, the expression levels of Matrix metalloproteinase-12 (MMP12), Caspase-associated recruitment domain 14 (CARD14), and Chitinase 3-like 1 (CHI3L1) were confirmed by semi-quantitative RT-PCR. A two-way clustering algorithm divided the 36 samples into three categories and the overall correct classification efficiency was 80.6% (29/36). Almost all of these genes (31/34) showed constant changes in the process of normal gastric epithelial cells to mGED to gastric cancer.

Conclusions  The results of this study provided global gene expression profiles during the development and progression from normal gastric epithelial cells to mGED to gastric cancer. These data may provide new insights into the molecular pathology of gastric cancer which may be useful for the detection, diagnosis, and treatment.

     

Efficacy of local aspiration in the conservative treatment of live interstitial pregnancy coexisting with live intrauterine pregnancy after in vitro fertilization and embryo transfer

Background  Heterotopic pregnancy (HP) is defined as a pregnancy in which one or more embryos is viably implanted in the uterus while the other is implanted elsewhere as an ectopic pregnancy. The occurrence of HP rises dramatically with the increased use of assisted reproductive technology. HP of interstitial pregnancy is one special situation which needs more concern. Here we evaluate the efficacy of local aspiration and instillation of hyperosmolar glucose in the treatment of live interstitial pregnancy complicated with live intrauterine pregnancy after in vitro fertilization and embryo transfer.

Methods  Five female patients were diagnosed with live interstitial pregnancies complicated with intrauterine pregnancies. They were treated with transvaginal ultrasound-guided aspiration of interstitial pregnancy and instillation of hyperosmolar glucose at the Center for Reproductive Medicine of Peking University Third Hospital from January 1st, 2008 to May 30th, 2011.

Results  Gemmule embryos in all 5 cases were aspirated successfully and there was no abdominal hemorrhage, threatened abortion or infection in any of the cases. The sac of interstitial pregnancy continued to progress after aspiration and stopped growing between 11 to 20 weeks. By the 30th week of pregnancy, 80% of the interstitial masses had disappeared. Four cases have delivered and one is still in on-going pregnancy. All of the four cases underwent cesarean section and there were nothing special detected in the corner of the uterus.

Conclusion  Local aspiration and instillation of hyperosmolar glucose may be an effective way to treat live interstitial pregnancy when coexisting with a live intrauterine pregnancy.

     

Total endoscopic nephroureterectomy for native kidney ipsilateral to transplanted kidney

Background  From limited exposure with management of the native distal ureter ipsilateral to the transplanted kidney, we usually choose open nephroureterectomy (NU) or laparoscopic NU combined with an open approach in renal transplant (RTx) recipients. We herein describe our preliminary experience with total endoscopic NU with bladder cuff (BC) excision and evaluate its feasibility for RTx recipients.

Methods  From August 2008 to June 2011, eight RTx recipients underwent total endoscopic NU with BC excision for clinically presumed native upper urinary tract urothelial carcinoma (UUT-UC) ipsilateral to the transplanted kidney. Cystoscopic circumferential excision of the ipsilateral ureteral orifice with BC was followed by retroperitoneal laparoscopic NU using early ureteral ligation without primary BC closure. The intact specimen was removed through a 3-cm flank incision (an enlarged trocar site). Perioperative and pathological data and oncological outcomes were collected and analyzed.

Results  All endoscopic procedures were completed successfully without major complications and with open conversion. The mean estimated blood loss was 100 ml with no blood transfusion. The mean operating room time was 234.8 minutes, mean time to ambulation was 2.6 days, and mean hospital stay was 9.0 days. Pathological findings confirmed UUT-UC in seven recipients, two with bladder UC. During the mean 25.2-month follow-up, none of the recipients developed recurrence, while two developed contralateral UUT-UC after the first NU.

Conclusion  Total endoscopic NU with BC excision is technically feasible and safe for RTx recipients.

     

Autologous bone marrow stem cell transplantation in critical limb ischemia: a meta-analysis of randomized controlled trials

Background  Amputation-free survival (AFS) has been recommended as the gold standard for evaluating No-Option Critical Limb Ischemia (NO-CLI) therapy. Early-phase clinical trials suggest that autologous bone-marrow derived cells (BMCs) transplantation may have a positive effect on patients with NO-CLI, especially decreasing the incidence of amputation. However, the BMCs therapeutic efficacy remains controversial and whether BMCs therapy is suitable for all CLI patients is unclear.

Methods  We conducted a meta-analysis using data from randomized controlled trials (RCTs) by comparing autologous BMCs therapy with controls in patients with critical limb ischemia, and the primary endpoint is the incidence of amputation. Pubmed, EBSCO and the Cochrane Central Register of Controlled Trials (to approximately July 25, 2012) were searched.

Results  Seven RCTs with 373 patients were enrolled in the meta-analysis. Because serious disease was the main reason leading to amputation in one trial, six studies with 333 patients were finally included in the meta-analysis. Pooling the data of the final six studies, we found that BMCs therapy significantly decreased the incidence of amputation in patients with CLI (odds ratio (OR), 0.37; 95% confidence interval (CI), 0.22 to 0.62; P=0.0002), and the efficacy had not significantly declined within 6 months after BMCs were transplanted; OR, 0.33; 95% CI, 0.16 to 0.70; P=0.004 within 6 months and OR, 0.30; 95% CI, 0.11 to 0.79; P=0.01 within 3 months. The rate of AFS after BMCs therapy was significantly increased in patients with Rutherford class 5 CLI (OR 3.28; 95% CI, 1.12 to 9.65; P=0.03), while there was no significant improvement in patients with Rutherford class 4 (OR 0.35; 95% CI, 0.05 to 2.33; P=0.28) compared with controls. The BMCs therapy also improved ulcer healing (OR, 5.83; 95% CI, 2.37 to 14.29; P=0.0001).

Conclusions  Our analysis suggests that autologous BMCs therapy has a beneficial effect in decreasing the incidence of amputation and the efficacy does not decrease significantly within 6 months after BMCs transplantation. Patients with Rutherford class 5 are suitable for BMCs therapy, while the efficiency in patients with Rutherford 4 needs further evaluation.

     

Anteroapical aneurysm plication improves mechanical intraventricular dyssynchrony in patients with anterior myocardial infarction

Background  Left ventricular (LV) dyssynchrony has been described to occur in patients with myocardial infarction. Dyssynchrony of left ventricular mechanical contraction produces adverse hemodynamic consequences. This study aimed to test the capacity of geometric rebuilding by aneurysm plication to restore a more synchronous contractile pattern after a mechanical, rather than electrical, intervention.

Methods  A total of sixty patients with anterior myocardial infarction, QRS duration <120 ms, electively undergoing operation between January 2008 and January 2010 were included for analysis. Real-time 3-dimensional echocardiography was performed to assess LV function, LV systolic and diastolic dyssynchrony by measuring ejection fraction (EF), peak ejection rate (PER), peak filling rate (PFR) and LV dyssynchrony. LV dyssynchrony was defined as the systolic dyssynchrony of the time to reach the minimum systolic volume for 16 LV segments, expressed in percent cardiac cycle, systolic dyssynchrony index (SDI). We compared changes of LV dyssynchrony at different interval times.

Results  LV contraction was significantly asynchronous because preoperative SDI was higher, EF, PER and PFR were lowered. Compared with function after operation, LV mechanical intraventricular resynchronization was improved with decreased SDI ((8.7±0.5) % vs. (14.3±1.6) %, P=0.01); LV function was improved with EF increasing ((43±9)% vs. (37±7)%, P=0.001), and LV systolic and diastolic dyssynchrony was improved with more rapid PFR (199.4±15.6 vs. 148.4±21.2, P=0.002) and PER (212.4±14.5 vs. 156.3±26.2, P=0.001).

Conclusions  Systolic and diastolic dyssynchrony was highly prevalent in patients with aneurysm, irrespective of QRS duration. Aneurysm plication produces a mechanical intraventricular resynchronization.

     

Chronic intermittent hypoxia aggravates cardiomyocyte apoptosis in rat ovariectomized model

Background  The prevalence of obstructive sleep apnea (OSA) increases after menopause in women, but remains under diagnosed because of social or lifestyle factors. It is important to evaluate the hazards of OSA on cardiovascular disease in menopausal women. We tested the hypothesis that chronic intermittent hypoxia (CIH) may aggravate cardiomyocyte apoptosis in ovariectomized (OVX) Sprague Dawley (SD) rats; the changes of anti-oxidation ability in cardiac muscles may be one of the reasons for cardiomyocyte apoptosis.

Methods  Forty-eight 60-day old female SD rats were randomly divided into a CIH group, OVX group, OVX+CIH (OC) group, and handled control (HC) group, and the rats were exposed either to CIH (nadir O₂ 6%) or handled normoxic controls. The changes of body weight and whole heart weight were measured. Super oxide dismutase (SOD) and malonaldehyde (MDA) were used to evaluate the level of oxidative stress. TdT-mediated dUTP nick end labeling (TUNEL) was used to measure apoptosis in each rat. Western blotting was used to measure apoptosis associated proteins in cardiac muscle samples from each rat.

Results  When compared with the HC and CIH groups, the levels of oxidative stress in the OC and OVX groups were significantly higher. The levels of SOD in the HC, CIH, OC, and OVX groups were (47.99±4.89), (53.60±4.47), (20.99±2.72), and (30.64±3.79) mmol/mg protein; significantly increased in the CIH group (P <0.05) and significantly decreased in the OC (P <0.01) and OVX (P <0.05) groups. The levels of MDA in the HC, CIH, OVX, and OC groups were (1.63±0.20), (1.93±0.77), (3.30±0.39), and (1.95±0.20) mmol/mg protein; it significantly increased in the CIH (P <0.05), OC (P <0.01), and OVX (P <0.05) groups compared with the HC group. Bax protein expression was significantly increased and bcl-2 protein expression was significantly reduced after CIH compared with HC rats (P <0.05). The protein expression of bax and bcl-2 in the OC group was not significantly different from the CIH group, but the ratio of bax/bcl-2 was significantly increased in the OC group (P <0.05); this was associated with severe cardiomycyte apoptosis in the OC group. TUNEL confirmed this observation.

Conclusions  This study found that CIH may induce oxidative stress in OVX rats but not in CIH rats, and cause more severe cardiomyocyte apoptosis in OVX rats compared with CIH rats. This means that OVX rats exposed to CIH suffered more severe cardiac injury compared with CIH rats due to reduced antioxidation. These findings may partly explain the reason why OSA has a worse cardiovascular impact on menopausal women, and emphasize the importance of detection and early treatment of OSA in menopausal patients.

     

Folfox4 regimen administered through combined hepatic arterial and systemic infusion for treatment of colorectal cancer with unresectable liver metastases

Background  Hepatic arterial infusion chemotherapy for liver metastases is under evaluation because of the high target dose and low general toxicity. To investigate the efficacy and safety of a Folfox4 regimen administered through a combined hepatic arterial and systemic infusion for the first-line treatment of colorectal cancer (CRC) with unresectable liver metastases.

Methods  Twenty-seven CRC patients with unresectable hepatic metastases and no prior chemotherapy were enrolled into the study. They received a Folfox4 regimen; 1st day: HAI of oxaliplatin 85 mg/m² and L-folinic acid 200 mg/m², followed by a bolus hepatic arterial injection of 5-fluorouracil 400 mg/m², then continuous HAI of 5-FU 600 mg/m²; 2nd day: infusion of L-folinic acid 200 mg/m² i.v. followed by an intravenous bolus injection of 5-Fluorouracil 400 mg/m², then continuous infusion of 5-fluorouracil 600 mg/m² i.v. The patients received HAI during the odd cycles, and the intravenous administration of the same Folfox4 regimen during the even cycles.

Results  A total of 236 treatment cycles were given with a median of 10 cycles. The therapy generated the following results after six treatment cycles: complete response (CR) 1/27 (3.7%), partial response (PR) 17/27 (63.0%), stable disease (SD) 6/27 (22.2%), and progress disease (PD) 3/27 (11.1%). Five patients had hepatectomy. The serum levels of both carcinoembryonic antigen (CEA) and CA19-9 were significantly reduced (P<0.05). A median time to progression of 11 months and a median overall survival of 24 months were documented. The major adverse events included grade 1/2 nausea/vomiting, upper abdominal pain, peripheral neuropathy, and neutropenia/ thrombocytopenia.

Conclusions  The Folfox4 regimen administered through combined hepatic arterial and systemic infusions is efficacious and safe for the treatment of CRC with unresectable liver metastases, and it facilitates the control of local lesions.

     

Axial and tangential views of the acromioclavicular joint: the introduction of new projections

Background  Routine anteroposterior radiographs of the acromioclavicular (AC) joint with or without weight bearing have limitations in demonstrating the AC joint. Transarticular fixation with Kirschner wire is a treatment choice for AC dislocations. However, percutaneous fixation of the AC joint is technically demanding. The C-arm fluoroscopy can be used as routine intraoperative guidance to facilitate this procedure. The current study aims to introduce new projections, the axial and tangential views of AC joint, to help evaluate the severity of the injury and facilitate the percutaneous procedure.

Methods  Three shoulder specimens were used to find the projection directions of the axial and tangential views of the AC joint by using the digital radiography (DR) unit. The axial and tangential views were taken of 20 adult volunteers by referencing the projection directions determined in the shoulder specimens. The angles showed on the DR system and the angles between the coronal plane of the body and the vertical plane of the flat panel detector (FPD) during taking these radiographs were recorded. The C-arm fluoroscopy unit was used to take the axial and tangential views referencing the angles measured on the DR system. Routine anteroposterior radiographs of the AC joint were taken on the volunteers. The minimal distances from the distal clavicle to the acromion were measured on both tangential and anteroposterior radiographs. The data was statistically analyzed.

Results  The clear axial and tangential radiographs of AC joints of the volunteers were obtained using both DR and C-arm fluoroscopy units. The angles demonstrated on the DR window are (20.8±2.4)° for male and (18.3±2.3)° for female. During taking the axial views, the angles between the coronal plane of the body and vertical plane of FPD are (23.3±3.2)° for male and (20.1±2.4)° for female. During taking tangential views, the corresponding angles are (117.5±3.7)° for male and (113.1±3.3)° for female. On the tangential radiographs, the minimal distance from the distal clavicle to the acromion is (6.1±1.2) mm, wider than the same measurement on the anteroposterior radiographs (P <0.05). Statistical analyses showed no significant differences in the above-mentioned angles and the minimal distances between the left and right AC joints (P >0.05). There were no significant differences in the above-mentioned angles between DR and C-arm fluoroscopy units (P >0.05).

Conclusions  The axial and tangential radiographs of the AC joint can demonstrate the joint clearly and they can be easily obtained with both DR system and C-arm fluoroscopy unit in similar projection directions.

     

Effects of laser irradiation on Trichophyton rubrum growth and ultrastructure

Background  Trichophyton rubrum (T. rubrum) is the most common causative agent of dermatophytosis worldwide. In this study, we examined the effect of laser irradiation on the growth and morphology of T. rubrum.

Methods  Colonies of T. rubrum were isolated (one colony per plate), and randomly assigned to 5 treatment groups: Q-switched  694 nm ruby laser treatment, long-pulsed Nd:YAG 1064 nm laser treatment, intense pulsed light (IPL) treatment, 308 nm excimer laser treatment and the blank control group without treatment. Standardized photographs were obtained from grown-up fungal plates prior to treatment. Colonies were then exposed to various wavelengths and fluences of laser light. To compare the growth of colonies, they were re-photographed under identical conditions three and six days post-treatment. To investigate the morphology of T. rubrum, scanning electron microscope (SEM) and transmission electron microscope (TEM) images were obtained from specimens exposed to 24 hours of laser treatment.

Results  Growth of T. rubrum colonies was significantly inhibited following irradiation by 694 nm Q-switched and 1064 nm long-pulsed Nd:YAG lasers. Other treatments exerted little or no effect. Q-switched laser irradiation exerted a stronger growth inhibitory effect than long-pulsed Nd:YAG laser irradiation. Following treatment by the Q-switched ruby laser system, T. rubrum hyphae became shrunken and deflated, and SEM images revealed rough, fractured hyphal surfaces, punctured with small destructive holes. TEM images showed that the hyphae were degenerating, as evidenced by the irregular shape of hyphae, rough and loose cell wall, and obscure cytoplasmic texture. Initially high electron density structure was visible in the cell; later, low-density structure appeared as a result of cytoplasmic dissolution. In contrast, the blank control group showed no obvious changes in morphology.

Conclusion  The Q-switched 694 nm ruby laser treatment significantly inhibits the growth and changes the morphology of T. rubrum.

     

Pre-treatment with bone marrow-derived mesenchymal stem cells inhibits systemic intravascular coagulation and attenuates organ dysfunction in lipopolysaccharide-induced disseminated intravascular coagulation rat model

Background  Bacterial lipopolysaccharide (LPS) can activate immunological cells to secrete various proinflammatory cytokines involved in the pathophysiological process of disseminated intravascular coagulation (DIC) during infection. In recent years, it has been found that bone marrow-derived mesenchymal stem cells (BMSCs) can affect the activity of these immune cells and regulate the secretion of proinflammatory cytokines. Here, we report the possible protective effect of BMSCs pre-treatment in LPS-induced DIC rat model and the mechanism.

Methods  Forty-eight adult male rats were divided into five experimental groups and one control group with eight animals in each group. In the treatment groups, 0, 1´10⁶, 2´10⁶, 3´10⁶, and 5´10⁶ of BMSCs were injected intravenously for 3 days before LPS injection, while the control group was treated with pure cell culture medium injection. Then, the LPS (3 mg/kg) was injected via the tail vein in the treatment groups, while the control group received 0.9% NaCl. Blood was withdrawn before and 4 and 8 hours after LPS administration. The following parameters were monitored: platelets (PLT), fibrinogen (Fib), D-dimer (D-D), activated partial thromboplastin time (APTT), prothrombin time (PT), tumor necrosis factor-a (TNF-a), interferon-g (IFN-g), interleukin-1b (IL-1b), creatinine (Cr), alanine aminotransferase (ALT), creatinine kinase-MB (CK-MB), and endothelin (ET).

Results  Compared with the control group, a significant change of coagulation parameters were found in the experimental groups. The plasma level of the inflammatory mediator (TNF-a, IFN-g, IL-1b), organ indicator (Cr, ALT, and CK-MB), and ET in the experimental groups were much lower (P <0.05) than that in the control group. Furthermore, some of these effects were dose-dependent; the statistical comparison of the plasma levels between the groups (from group 2 to group 5) showed a significant difference (P <0.05), except the ALT and CK-MB levels (P >0.05).

Conclusion  Pre-treatment with BMSCs can attenuate organ dysfunction and inhibit systemic intravascular coagulation effectively via the regulatory effect on immune cells and proinflammatory cytokines in LPS-induced DIC rat model.

     

Tissue-engineered calcium phosphate cement in rabbit femoral condylar bone defects

Background  Calcium phosphate cement (CPC) is a favorable bone-graft substitute, with excellent biocompatibility and osteoconductivity. However, its reduced osteoinductive ability may limit the utility of CPC. To increase its osteoinductive potential, this study aimed to prepare tissue-engineered CPC and evaluate its use in the repair of bone defects. The fate of transplanted seed cells in vivo was observed at the same time.

Methods  Tissue-engineered CPC was prepared by seeding CPC with encapsulated bone mesenchymal stem cells (BMSCs) expressing recombinant human bone morphogenetic protein-2 (rhBMP-2) and green fluorescent protein (GFP). Tissue-engineered CPC and pure CPC were implanted into rabbit femoral condyle bone defects respectively. Twelve weeks later, radiographs, morphological observations, histomorphometrical evaluations, and in vivo tracing were performed.

Results  The radiographs revealed better absorption and faster new bone formation for tissue-engineered CPC than pure CPC. Morphological and histomorphometrical evaluations indicated that tissue-engineered CPC separated into numerous small blocks, with active absorption and reconstruction noted, whereas the residual CPC area was larger in the group treated with pure CPC. In the tissue-engineered CPC group, in vivo tracing revealed numerous cells expressing both GFP and rhBMP-2 that were distributed in the medullar cavity and on the surface of bony trabeculae.

Conclusion  Tissue-engineered CPC can effectively repair bone defects, with allogenic seeded cells able to grow and differentiate in vivo after transplantation.

     

Reconstruction of segmental bone defects in the rabbit ulna using periosteum encapsulated mesenchymal stem cells-loaded poly(lactic-co-glycolic acid) scaffolds

Background  Repair of large bone defects remains a challenge for clinicians. The present study investigated the ability of mesenchymal stem cells (MSCs) and/or periosteum-loaded poly(lactic-co-glycolic acid) (PLGA) to promote new bone formation within rabbit ulnar segmental bone defects.

Methods  Rabbit bone marrow-derived MSCs (passage 3) were seeded onto porous PLGA scaffolds. Forty segmental bone defects, each 15 mm in length, were created in the rabbit ulna, from which periosteum was obtained. Bone defects were treated with either PLGA alone (group A), PLGA + MSCs (group B), periosteum-wrapped PLGA (group C) or periosteum-wrapped PLGA/MSCs (group D). At 6 and 12 weeks post-surgery, samples were detected by gross observation, radiological examination (X-ray and micro-CT) and histological analyses.

Results  Group D, comprising both periosteum and MSCs, showed better bone quality, higher X-ray scores and a greater amount of bone volume compared with the other three groups at each time point (P <0.05). No significant differences in radiological scores and amount of bone volume were found between groups B and C (P >0.05), both of which were significantly higher than group A (P <0.05). 

Conclusions  Implanted MSCs combined with periosteum have a synergistic effect on segmental bone regeneration and that periosteum plays a critical role in the process. Fabrication of angiogenic and osteogenic cellular constructs or tissue-engineered periosteum will have broad applications in bone tissue engineering.

     

Long-pulse Nd:YAG 1064-nm laser treatment for onychomycosis

Background  Recent research shows that lasers can inhibit fungal growth and that Nd:YAG 1064-nm lasers can penetrate as deep as the lower nail plate. The aim of this study was to observe the effect of a long-pulse Nd:YAG 1064-nm laser on 154 nails of 33 patients with clinically and mycologically proven onychomycosis.

Methods  Thirty-three patients with 154 nails affected by onychomycosis were randomly assigned to two groups, with the 154 nails divided into three sub-groups (II degree, III degree, and IV degree) according to the Scoring Clinical Index of Onychomycosis. The 15 patients (78 nails) in group 1 were given eight sessions with a one-week interval, and the 18 patients (76 nails) in group 2 were given four sessions with a one-week interval.

Results  In group 1, the effective rates at 8 weeks, 16 weeks, and 24 weeks were 63%, 62%, and 51%, respectively, and the effective rates in group 2 were 68%, 67%, and 53% respectively. The treatment effect was not significantly different between any sub-group pair (P >0.05).

Conclusions  Long pulse Nd:YAG 1064-nm laser was effective for onychomycosis. It is a simple and effective method without significant complications or side effects and is expected to become an alternative or replacement therapy for onychomycosis.

     

Endovascular recanalization of superior vena cava, brachiocephalic, and subclavian venous occlusions caused by nonmalignant lesions

Background  Endovascular recanalization (EVR) is becoming the primary therapy for patients with central venous (brachiocephalic, subclavian, and superior vena cava) occlusion (CVO) caused by benign etiology. In this study, we retrospectively analyzed our experience in using EVR to treat benign CVO in 10 patients between April 2005 and September 2010.

Methods  The mean age of the patients was 65.3 years, 2/10 cases were female, and the origin of cause of CVO in 7/10 cases was the hemodialysis access in the upper extremity. The patients were treated with primary stent placement and evaluated with immediate technical success rate and post-interventional patency rate after the procedure.

Results  Eight patients were treated successfully with stent placement and experienced symptomatic relief immediately. No technical complications were observed during EVR treatment. Patients were followed up by ultrasonography and venography. Median follow-up was 13 months. Three patients required secondary procedures to maintain patency.

Conclusions  EVR is an effective and safe treatment in patients with benign CVO. It provides immediate symptom relief and maintains a continuous access for hemodialysis.

     

Rotational Alignment in Total Knee Arthroplasty: Nonimage-based Navigation System Versus Conventional Technique

Background  Proper rotational alignment during total knee arthroplasty (TKA) is important for adequate postoperative patellofemoral and tibiofemoral kinematics, as well as for achieving balanced flexion space at 90º. The effects of computer navigation-assisted total knee replacement and conventional total knee arthroplasty on rotational alignment, mechanical axis, component position and clinical outcomes were compared.

Methods  Two methods were used in 82 patients and the rotation of the femoral and tibial components in the transverse plane, the combined rotation of the two components, the mismatch between them, and the mechanical axis of the lower limb were analyzed. All of these parameters were measured from postoperative radiographs and computed tomography images. Functional outcomes were compared at 6 weeks and 6 months postoperatively.

Results  Significant differences were found between the two techniques (P <0.05) in the following parameters: average rotation of the femoral component ((1.51±3.55)º vs. (−0.63±3.04)º); combined rotation of the femoral and tibial components (2.85±4.07)º vs. (0.28±3.43)º); and mismatch between the femoral and tibial components ((1.44±4.55)º vs. (−0.43±2.86)º). Differences in the rotation of the tibial component were not statistically significant. The prevalence of outliers (malalignment >±3° internal/external rotation) of the femoral component (31.7% vs. 12.5%) and the tibial component (36.6% vs. 15%) were significantly reduced when the navigation system was used (P <0.05). In addition, while patients in the navigation group had significantly better mechanical axis and functional outcomes at 6 weeks after surgery (P <0.05), there was no significant difference between the two groups (P >0.05) with respect to functional outcomes at 6 months.

Conclusion  The navigation system exhibited higher accuracy than the conventional technique in the transverse and coronal plane, and provided better early functional outcomes.

     

Steady-state pharmacokinetics of zidovudine in Chinese HIV-infected patients

Background  The pharmacokinetics of zidovudine (AZT) are possibly influenced by weight, age, sex, liver and renal functions, severity of disease, and ethnicity. Currently, little information is available on the steady-state pharmacokinetics of AZT in Chinese HIV-infected patients. The current study aimed to characterize the steady-state pharmacokinetics of AZT in a Chinese set-up.

Methods  Eleven Chinese HIV-infected patients were involved in the steady-state pharmacokinetic study. In total, 300 mg of AZT, as a part of combination therapy, was given to patients, and serial blood samples were collected for 12 hours. The samples were measured by a high-performance liquid chromatography (HPLC) assay, and the results were analyzed by both the non-compartment model and the one-compartment model.

Results  The C_max of AZT in Chinese patients was higher than that in non-Asian patients. The half-life of AZT, analyzed by the non-compartment model (P=0.02), in male patients ((1.02±0.22) hours) was shorter than that of AZT in female patients ((1.55±0.29) hours). The AZT clearance, analyzed by the one-compartment model (P=0.045), in male patients ((262.60±28.13) L/h) was higher than that in female patients ((195.85±60.51) L/h).

Conclusion  The present study provides valuable information for the clinical practice of AZT-based highly active antiretroviral therapy in a Chinese set-up.