PTH and ibandronate are proven to be effective in reversing negative effects of postmenopausal osteoporosis in terms of bone architecture and density. However, the changes of viscoelastic properties of the bone during the pathogenesis of osteoporosis and its treatment were seldom studied. Thus, this study aimed at studying the viscoelastic changes in PTH and ibandronate treated ovariectomized rat to assess the efficacy of the treatments. In this study, distal femurs of twenty-two female rats from four different groups (SHM, OVX, PTH and IBN) were evaluated using CT, pQCT and nanoindentation tests. While density parameters were well preserved in ibandronate treated group, elastic modulus and hardness were found to be better in PTH treated group. Thus, cortical and trabecular bone could be differentially affected by these two categories of drug, due to their difference in the action of mechanism. Moreover, viscosity of the cortical bone showed a positive correlation (R(2)=0.72) with bone strength predictor SSIy, which would possibly correlate with fracture risk.
Animals ; Diphosphonates ; Elastic Modulus ; Female ; Femur ; Hardness ; Humans ; Osteoporosis ; Osteoporosis, Postmenopausal ; Rats ; Viscosity

BACKGROUND: Osteolytic metastasis is a common destructive form of metastasis, in which there is an increased bone resorption but impaired bone formation. It is hypothesized that the changed mechanical properties of tumor affected bone cells could inhibit its mechanosensing, thus contributing to differences in bone remodeling. METHODS: Here, atomic force microscopy indentation on primary bone cells exposed to 50% conditioned medium from Walker 256 (W) carcinoma cell line or its adaptive tumor (T) cells was carried out. Nitric oxide levels of bone cells were monitored in response to low-magnitude, high-frequency (LMHF) vibrations. RESULTS: A stronger sustained inhibitive effect on bone cell viability and differentiation by T cells as compared to that of its cell line was demonstrated. This could be attributed to the higher levels of transforming growth factor-β1 (TGF-β1) in the T-conditioned medium as compared to W-conditioned medium. Bone cell elastic moduli in W and T-groups were found to decrease significantly by 61.0% and 69.6%, respectively compared to control and corresponded to filamentous actin changes. Nitric oxide responses were significantly inhibited in T-conditioned group but not in W-conditioned group. CONCLUSIONS: It implied that a change in cell mechanical properties is not sufficient as an indicator of change in mechanosensing ability. Moreover, inhibition of phosphoinositide 3-kinase/Akt downstream signaling pathway of TGF-β1 alleviated the inhibition effects on mechanosensing in T-conditioned cells, further suggesting that growth factors such as TGF-β could be good therapeutic targets for osteoblast treatment.
Actins ; Bone Neoplasms ; Bone Remodeling ; Bone Resorption ; Cell Line ; Cell Survival ; Culture Media, Conditioned ; Elastic Modulus ; Intercellular Signaling Peptides and Proteins ; Microscopy, Atomic Force ; Neoplasm Metastasis ; Nitric Oxide ; Osteoblasts ; Osteogenesis ; Sensitivity Training Groups ; T-Lymphocytes ; Vibration ; Walkers

PURPOSE: Bone metastasis invariably increases morbidity and mortality. This study compares the effects of ibandronate and paclitaxel on bone structure and its mechanical properties and biochemical turnover in resorption markers using an immunocompetent Walker 256-Sprague-Dawley model, which was subjected to tumor-induced osteolysis. MATERIALS AND METHODS: Seventy rats were divided equally into 4 groups: 1) sham group (SHAM), 2) tumor group (CANC), 3) ibandronate treated group (IBAN), and 4) paclitaxel treated group (PAC). Morphological indices [bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp)] and mechanical properties (failure load, stiffness) were evaluated after thirty days of treatment period. Bone resorption rate was analysed using serum deoxypyridinoline (Dpd) concentrations. RESULTS: Morphological indices showed that ibandronate (anti-resorptive drug) had a better effect in treating tumor-induced architectural changes in bone than paclitaxel (chemotherapeutic drug). The deterioration in bone architecture was reflected in the biomechanical properties of bone as studied with decreased failure load (F(x)) and stiffness (S) of the bone on the 30th day postsurgery. Dpd concentrations were significantly lower in the IBAN group, indicating successful inhibition of bone resorption and destruction. CONCLUSION: Ibandronate was found to be as effective as higher doses of paclitaxel in maintaining stiffness of bone. Paclitaxel treatment did not appear to inhibit osteoclast resorption, which is contrary to earlier in-vitro literature. Emphasis should be placed on the use of immunocompetent models for examining drug efficacy since it adequately reflects bone metastasis in clinical scenarios.
Amino Acids ; Animals ; Biomechanical Phenomena/*drug effects/physiology ; Bone Density/drug effects/physiology ; Bone Neoplasms/*drug therapy ; Bone Resorption/*chemically induced ; Diphosphonates/*pharmacology ; Immunocompetence ; Male ; *Neoplasm Metastasis ; *Osteolysis ; Paclitaxel/*pharmacology ; Rats ; Rats, Sprague-Dawley

BACKGROUND: Several stents are now available for the treatment of failed or suboptimal angioplasty. However, one of the limitations of stents is difficult to deploy especially in tortuous vessels, lesions at a bend, and distal to previously deployed stents. The AVE Micro-II stent has a very low profile(1.65mm), optimum radio-opacity, and highly flexible properties. It is mounted on a semi-compliant balloon with a monorail delivery system. Therefore, it is easy to operate and feasible in tortuous, distal lesions and variety of lesion lengths. We report clinical outcomes and angiographic follow up results of AVE Micro-II stent. METHODS: Between January 1996 and September 1996, 77 patients were stented with the AVE Micro-II stent. Six-months follow-up angiogram was performed in 57 patients(64 lesions, follow-up rate : 74%). RESULTS: The overall angiographic restenosis rate was 26.6%. By univariable analysis, the rate of restenosis was significantly higher for stents in angulated lesions, in smaller post-stent luminal diameter, in the left anterior descending artery lesion than the right coronary artery, in ostial lesion(p=0.02), in peristent dissecting lesions(p=0.02), in tortuous proximal vessels(p=0.03). Stenting of angulated lesions(p=0.0001, Odds ratio=54.64), small post-stent luminal diameter(p=0.01, Odds ratio=5.46), and the left anterior descending artery than the right coronary artery(p=0.03, Odds ratio=17.2) were the strong independent predictors of restenosis in a multiple logistic regression analysis. Event-free survival(freedom from death, myocardial infarction or revascularization) was 80.7% at 6 months. CONCLUSIONS: 1) The AVE Micro-II stent can be placed safely and efficiently. 2) The angiographic restenosis rate was 26.6%, and 80.7% of patients remained free of cardiovascular events at 6 months. 3) Stenting of angulated lesions, small post-stent luminal diameter, and the left anterior descending artery than the right coronary artery are associated with higher rates of restenosis.
Angioplasty ; Arteries ; Coronary Vessels ; Disease-Free Survival ; Follow-Up Studies* ; Humans ; Logistic Models ; Myocardial Infarction ; Phenobarbital ; Stents*

BACKGROUND: Despite of the first coronary wallstent implantation ushered in the new era in interventional cardiology with the purpose of circumventing the two major limitation of coronary balloon angioplasty, early acute occlusion and late restenosis, however, previous investigators suggested the high rate of subacute occlusion after original wallstent implantation. Recently the low incidence of the subacute closure and restenosis rate with the newely modified less shortening coronary wallstent in native coronary artery and in aortocoronary vein grafts were reported. In this study we report the acute and 6 months follow up results with less shortening coronary wall stent in 32 patients. METHODS: Thirty two patients were enrolled from March 1996 through February 1997 at the Yonsei cardiovascular center of Yonsei University. The specific angiographic criteria for enrollment included at least 70% stenosis and a lesion that was 20mm or more in length and a vessel diameter of at least 2.5mm. Enteric coated aspirin(100mg daily) and ticlopidine(500mg daily) at least 3 days before the procedure and received continuous infusion of 24,000U of heparin for 1day after the procedure. Angiography was performed in two orthogonal views at pre, post procedure and 6months later. Quantitative analysis was performed with the use of the electronic caliper comparing to the empty catheter. All continuous variables were expressed as mean SD and analyzed with the t-test. Differences between groups were analyzed with Chi-square analysis and Fishers Exact test where appropriate. RESULTS: The newly modified Coronary Less Shortening Wallstents were successfully implanted in all the 35 diffuse coronary lesions(more than 20mm in length) of the 32 patients, including 15 pts of acute myocardial infarction, 14 pts of unstable angina, and 3 pts of stable angina. Average 6 months follow up angiography was performed in 26 patients. Immediate angiographic results with Less Shortening Wallstent comparing with 6 months follow up were 3.0+/-0.4mm and 1.7+/-0.9mm in minimal luminal diameter(MLD), 5.1+/-9.1% and 46.8+/-25.8% in diameter stenosis(DS). During the in-hospital phase, no major cardiac event occurred except 2 cases of transmural myocardial infarction, including one of stent thrombosis(3.1%) and one of side branch occlusion, despite of inclusion of 7 cases of threatened occlusion in the long lesion. The restenosis rate at follow up angiography was 30.7%(8/26 pts). The restenosis rate was higher in patients with stent insertion into right coronary artery or adjuvant high pressure oversize ballooning after stent insertion but not statistically significant. CONCLUSIONS: The results of this study suggested that new Less Shortening Wallstent might reduce the requirement of multiple stent in the long lesion and a lower rate of subacute thrombotic occlusion in comparison to the reports with its prototype. Restenosis rate was not significantly different from other types of stents. Althouth the restenosis rate was high in patients with stent insertion, there was no statistical significance probably due to small sample size. But further large scale long term follow-up study is needed to evaluate the role of new Less Shortening Wallstent.
Angina, Stable ; Angina, Unstable ; Angiography ; Angioplasty, Balloon, Coronary ; Cardiology ; Catheters ; Constriction, Pathologic ; Coronary Artery Disease* ; Coronary Vessels* ; Follow-Up Studies* ; Heparin ; Humans ; Incidence ; Myocardial Infarction ; Phenobarbital ; Research Personnel ; Sample Size ; Stents ; Transplants ; Veins

Osteoporosis is a debilitating disease affecting the elderly population, associated with compromised stability and reduced mobility of the bone. Osteoporosis is diagnosed as a condition when the measured bone mineral density (BMD) falls below 2.5 standard deviations of peak mass. However, BMD alone might not be enough to define the osteoporotic condition because it does not accounts on the micro-architectural changes in the bone trabeculae. Thus, this study aimed at studying the micro-architecural changes in trabeculae rich bone metaphysis of ovariectomized rat models in comparison with the conventional BMD measurements and the mechanical parameters. In this study, proximal tibiae of twenty-five female rats from four different groups (SHAM, OVX, IBAN and PTH) were evaluated using micro-CT, pQCT and three point bending tests. The micro-CT analysis showed that the deterioration of trabecular bone was significant during the first 6 weeks after OVX surgery. During the early stage of osteoporosis, the trabecular density decreased more rapidly than the cortical density. Morphological analysis showed that early administration of both ibandronate and parathyroid hormone has a beneficial effect on restoring the trabecular structures. Bone mechanical properties of treatment groups did not show significant difference, but followed the overall trend as morphological indices. The results suggest that early administration of either ibandronate or PTH is effective in restoring the trabecular bone loss caused by osteoporosis. However, larger-scale studies should be conducted to better understand the effect of both anti-resorptive and anabolic treatments in terms of morphological and mechanical properties.
Aged ; Animals ; Bone Density ; Diphosphonates ; Female ; Humans ; Osteoporosis ; Parathyroid Hormone ; Rats ; Tibia

Background: Foot deformities can cause abnormal biomechanics of the ankle joint and the development of osteoarthritis. It was hypothesized that foot deformities would be related to medial ankle osteoarthritis, and this study investigated this relationship using radiographic measurements. Methods: Seventy-six ankles of 76 patients (32 men and 44 women; mean age, 69.0 years) with medial ankle osteoarthritis were included. Eleven radiographic measurements evaluated ankle joint orientation (tibial plafond inclination [TPI], medial distal tibial angle [MDTA], and anterior distal tibial angle [ADTA]), ankle joint incongruency (tibiotalar tilt [TT]), foot deformities (lateral talofirst metatarsal angle [Lat talo-1MT], anteroposterior talo-first metatarsal angle [AP talo-1MT], and talonavicular coverage), talar body migration (medial talar center migration [MTCM] and anterior talar center migration [ATCM]), internal rotation (IR) of the talus, and mechanical tibiofemoral angle. All were statistically analyzed using Pearson’s correlation coefficients and regression analyses. Results: Ankle joint orientation to the ground (TPI, p = 0.002), increased foot arch (Lat talo-1MT, p < 0.001), and IR of the talus (p = 0.001) were significantly associated with ankle joint incongruency (TT) in linear regression analysis. Ankle joint incongruency (TT, p = 0.003), medial talar body migration (MTCM, p = 0.042), and increased foot arch (Lat talo-1MT, p = 0.022) were significantly associated with IR of the talus in the binary logistic regression analysis. MTCM was significantly correlated with TPI (r = 0.251, p = 0.029), TT (r = 0.269, p = 0.019), MDTA (r = 0.359, p = 0.001), ATCM (r = –0.522, p < 0.001), and AP talo-1MT (r = 0.296, p = 0.015). ATCM was significantly correlated with TPI (r = –0.253, p = 0.027), ADTA (r = 0.349, p = 0.002), and Lat talo-1MT (r = –0.344, p = 0.002). Conclusions Ankle joint orientation, foot deformities, and talar rotation were associated with ankle joint incongruency in medial ankle osteoarthritis when evaluated radiographically. These findings need to be considered during surgical treatment for medial ankle osteoarthritis. However, the biomechanical significance of these radiographic measurements requires further investigation.

PURPOSE: Controversy exists over the preoperative risk factors for postoperative urinary retention after the midurethral sling procedure for stress urinary incontinence (SUI). We intended to analyze the effect of preoperative flow rate on postoperative urinary retention after the transobturator tape (TOT) operation. MATERIALS AND METHODS: A total of 322 patients who underwent TOT from June 2006 to May 2012 were included in this retrospective study. All patients were preoperatively investigated for urinary symptoms and underwent preoperative urodynamic studies including urine flow rate. Postoperative urinary retention, voiding difficulty, and uroflowmetry were checked. Urinary retention was defined as the need for additional catheterization longer than 1 day. Patients were divided by preoperative peak flow rate (Qmax) of 15 mL/s (low Qmax group and normal Qmax group). RESULTS: There were 3 cases of postoperative urinary retention (0.9%) and 52 cases of voiding difficulty (16.1%). The low Qmax group included 40 patients (12.4%) and the normal Qmax group included 282 patients (87.5%). Between the two groups, there were no significant differences in age, previous pelvic surgery history, or past medical history. The low Qmax group had higher scores for voided volume and detrusor pressure at Qmax. However, there was no significant difference in postoperative voiding difficulty between the two groups. Furthermore, three patients who experienced postoperative retention showed high flow rates preoperatively. CONCLUSIONS: Our results suggest that voiding difficulty in the group with low preoperative flow was tolerable and the treatment success rate was comparable to that in patients in the normal flow group. According to our analysis, patients with a low flow rate preoperatively can be safely treated with TOT for SUI.
Catheterization ; Catheters ; Humans ; Retrospective Studies ; Risk Factors ; Suburethral Slings* ; Urinary Incontinence ; Urinary Incontinence, Stress ; Urinary Retention ; Urodynamics

OBJECTIVES: This study investigated the correlation between bone mineral density (BMD)/trabecular bone score (TBS) and body mass index (BMI), height and weight in Korean adults. METHODS: We enrolled 2555 female participants in their 20s–80s and 1631 male participants in their 20s–70s. Participants with history of previous vertebral surgeries or current vertebral diseases were excluded. Female and male participants were divided into osteoporosis group (n = 136 and n = 31, respectively), osteopenia group (n = 822 and n = 460, respectively), and normal group (n = 1596 and n = 1140, respectively) based on their BMD T-score. Dual-energy X-ray absorptiometry image analysis and linear regression analysis were conducted on each participant in each group to determine the P-value and the correlation between BMD T-score/TBS T-score and BMI, weight, and height. RESULTS: We found a significant correlation between BMI and TBS in both male and female participants. In the male participants, the correlation coefficient increased progressively from the normal group to the osteoporosis group. In the female group, we observed a significant positive correlation between height and TBS, and in the male group a significant negative correlation between weight and TBS was observed. CONCLUSIONS: BMI and weight are closely correlated to body fat content. BMD was positively correlated to BMI and weight, while TBS was negatively correlated to BMI and weight. Therefore, although BMI causes an increase in BMD, it appears to be negatively affecting bone quality.
Absorptiometry, Photon ; Adipose Tissue ; Adult ; Body Mass Index* ; Bone Density ; Bone Diseases, Metabolic ; Female ; Humans ; Korea ; Linear Models ; Male ; Miners* ; Osteoporosis

BACKGROUND: Coronary stenting is known to reduce the rates of restenosis in focal lesions, but the efficacy of stents for long lesions have not been thoroughly defined. To evaluate the immediate and follow-up results of three different types of stents in lesions longer than 20mm, consecutive series of patients (pts) were reviewed. METHODS: Between February 1996 and January 1997, 123 patients (male 68.3%, mean age 57+/-10 years) with a total of 130 lesions underwent long stent : stenting. Excluding multiple stents and unplanned use for acute closure fifty-three pts (56 lesions) were treated with the Microstent II (M-II):30 pts (31 lesions) received the Less Shortening Wallstent (WA):and 40 pts (43 lesions) were treated by the Gianturco-Roubin II stent (GR-II). RESULTS: With the clinical success defined as <30% residual stenosis without death, CABG, Q-wave MI was achieved in 93% with the M-II, 94% with the WA and 95% with the GR-II. Stent thrombosis occurred 0% in M-II, 1.5% in WA and 2.3% in GR-II. Clinical success and stent thrombosis rates were not different between the three types of stents. Follow-up (FU) quantitative angiography was obtained from 34 pts (64%) in M-II, 25 lesions (83%) in WA and 26 pts (65%) in GR-II after 6 months. Restenosis rate defined as <0A65B>50% diameter stenosis at FU was 26% in M-II, 32% in WA and 38% in GR-II:there was no significant difference between the three stents. Target lesion revascularization (TLR) defined as CABG or target lesion PTCA at FU was 17.6% in M-II, 12% in WA and 23.1% in GR-II. Restenosis rate correlated closely with lesion length (p-value-0.03, Odds ratio-1.096) and small post-stent luminal diameter (p-value-0.002, Odds ratio-0.063) in a mu-ltivariable analysis. CONCLUSION: Coronary stenting for long lesions can be safely performed with acceptable complication rates using any of the three types of stents. Restenosis and late outcome was not related to type of stent.
Angiography ; Constriction, Pathologic ; Follow-Up Studies ; Humans ; Phenobarbital ; Stents* ; Thrombosis