Response of different PTH assays to therapy with sevelamer or CaCO<Subscript>3</Subscript> and active vitamin D sterols

Amino-terminally truncated parathyroid hormone (PTH) fragments are detected to differing degrees by first- and second-generation immunometric PTH assays (PTH-IMAs), and acute changes in serum calcium affect the proportion of these fragments in circulation. However, the effect of chronic calcium changes and different vitamin D doses on these PTH measurements remains to be defined. In this study, 60 pediatric dialysis patients, aged 13.9 ± 0.7 years, with secondary hyperparathyroidism were randomized to 8 months of therapy with oral vitamin D combined with either calcium carbonate (CaCO₃) or sevelamer. Serum phosphorus levels did not differ between groups. Serum calcium levels rose from 9.3 ± 0.1 to 9.7 ± 0.1 mg/dl during CaCO₃ therapy (p < 0.01 from baseline) but remained unchanged during sevelamer therapy. In the CaCO₃ and sevelamer groups, baseline serum PTH levels (1st PTH-IMA; Nichols Institute Diagnostics, San Clemente, CA) were 964 ± 75 and 932 ± 89 pg/ml, and levels declined to 491 ± 55 and 543 ± 59 pg/ml, respectively (nonsignificant between groups). Patients treated with sevelamer received higher doses of vitamin D than those treated with CaCO₃. The PTH values obtained by first- and second-generation PTH-IMAs correlated closely throughout therapy and the response of PTH was similar to both PTH-IMAs, despite differences in serum calcium levels.     

Serum insulin-like growth factor-I level is associated with the presence of vertebral fractures in postmenopausal women with type 2 diabetes mellitus

Summary Multivariate logistic regression analysis showed that serum IGF-I level was significantly lower in postmenopausal diabetic women with vertebral fractures than in those without fractures. Serum IGF-I level could be clinically useful for assessing the risk of vertebral fractures independent of BMD in postmenopausal women with type 2 diabetes. Introduction We investigated the relationships among serum IGF-I and C-peptide levels, BMD, and vertebral fractures in postmenopausal women with type 2 diabetes. Methods A total of 131 postmenopausal women with type 2 diabetes were consecutively recruited, and radiographic and biochemical characteristics were collected. Results Either IGF-I or C-peptide was not correlated with BMD at any site or bone metabolic markers, such as osteocalcin (OC) and urinary N-terminal cross-linked telopeptide of type-I collagen (uNTX). However, serum IGF-I level was significantly lower in subjects with vertebral fractures than in those without fractures (mean ± SD: 106.9 ± 50.0 vs. 142.8 ± 50.8 ng/ml, p = 0.0006). When multivariate logistic regression analysis was performed with the presence of vertebral fractures as a dependent variable and serum IGF-I adjusted for the parameters described above as independent variables, IGF-I was selected as an index affecting the presence of vertebral fractures [odds ratio = 0.436, 95% confidential interval 0.234–0.814 per SD increase, p = 0.0092]. This significance was almost the same after additional adjustment for lumbar BMD or C-peptide. Conclusions Serum IGF-I level could be clinically useful for assessing the risk of vertebral fractures independent of BMD in postmenopausal women with type 2 diabetes.     

Plasma Adhesion and Inflammation Markers: Asymmetrical Dimethyl-L-Arginine and Secretory Phospholipase A<Subscript>2</Subscript> Concentrations before and after Laparoscopic Gastric Banding in Morbidly Obese Patients

Background The aim of this study was to examine the relationship between subclinical inflammation and weight loss by laparoscopic adjustable gastric banding (LAGB). Methods Plasma concentrations of intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), sensitive C-Reactive Protein (sCRP), asymmetrical dimethyl-L-arginine (ADMA), Secretory Phospholipase A2 (sPLA2), and metabolic markers, such as homeostatic model assessment – insulin resistance (HOMA-IR) and body mass index (BMI) were determined in morbidly obese patients (n = 18, BMI 48.6 ± 1.7 kg/m²) at baseline and 1 month after operations. Baseline levels in patients were also compared with age-matched controls (n = 20, BMI 21.3 ± 1.8 kg/m²). Plasma ICAM-1,VCAM, sCRP and ADMA, and sPLA₂ concentrations were determined by enzyme-linked immunoassay methods and colorimetric method, respectively. Results Plasma sCRP, ICAM-1, ADMA and sPLA₂ concentrations and HOMA-IR were significantly higher in morbidly obese patients than in controls (for each, P < 0.01). Plasma VCAM-1 concentration was not changed in obese patients. HOMA-IR was significantly correlated with ICAM-1, ADMA and sPLA₂ in the obese group at baseline (for each, P < 0.01). There was a significant correlation between plasma sCRP and plasma glucose,VCAM-1, ICAM-1, ADMA and sPLA₂ concentrations (for each, P < 0.01). 1 month after LAGB, mean body weight loss was 13.2 ± 6.3 kg, and plasma sCRP and ADMA concentrations and HOMA-IR and BMI were significantly decreased (for each, P < 0.01). However, these levels cannot be decreased to the levels of the controls. Conclusion Obesity and insulin resistance appear to be associated with low-grade inflammation and endothelial dysfunction. Insulin resistance and endothelial dysfunction were improved by weight loss after LAGB.     

Increased augmentation index and central aortic blood pressure in osteoporotic postmenopausal women

Summary Osteoporosis has been associated with cardiovascular disease. We found increased augmentation index, a measure of wave reflections and arterial stiffness, and central pressures in osteoporotic postmenopausal women. They also showed a higher estimated aortic pulse wave velocity, indicating a stiffer aorta. These changes may increase cardiovascular risk in postmenopausal osteoporosis. Introduction Evidence suggests a link between osteoporosis and cardiovascular disease. We investigated whether augmentation index (AIx), a measure of pulse wave reflections and arterial stiffness, is increased and related to the osteoprotegerin (OPG)/receptor activator of nuclear factor-kappa B ligand (RANKL) system in postmenopausal osteoporosis. Methods AIx and central aortic haemodynamics were assessed using pulse wave analysis in 182 cardiovascular disease-free osteoporotic postmenopausal women and in 160 controls. Statistical analysis was performed by unpaired t test, Mann-Whitney test, Spearman‘s correlation coefficient, and multivariate linear regression analysis. Results AIx (37.2 ± 7.0 vs. 29.6 ± 9.2 %, P < 0.0001) and central aortic systolic (117.5 ± 12.1 vs. 111.4 ± 12.2 mmHg, P < 0.0001) and pulse (40.5 ± 10.3 vs. 36.4 ± 8.1 mmHg, P = 0.0007) pressures were significantly higher in osteoporotic patients than in controls. The estimated aortic pulse wave velocity (PWV) was also significantly higher in the osteoporotic group. In multivariate analysis for osteoporotic patients, femoral neck and lumbar spine bone mineral density T scores were independent negative predictors of AIx (P < 0.0001). AIx was not correlated with serum levels of OPG and RANKL. Conclusions Osteoporotic postmenopausal women show increased AIx and central aortic pressures, and a higher estimated aortic PWV, indicating a stiffer aorta. Such alterations may increase cardiovascular risk in postmenopausal osteoporosis.     

Effect of a long-term treatment with 1,25-dihydroxyvitamin D3 on osteocalcin in postmenopausal osteoporosis

Summary Serum bone Gla-protein (BGP or osteocalcin) was measured in 25 women with histologically confirmed postmenopausal osteoporosis before and during long-term treatment with 1 μg/day of 1,25-dihydroxyvitamin D₃(1,25(OH)₂D₃). Basal serum BGP was significantly lower in osteoporotic women (3.8±1.4 ng/ml) than in agematched controls (6.8±2.0 ng/ml). During 1,25(OH)₂D₃ therapy serum BGP increased so that the mean of the values observed on treatment (4.8±1.5) was significantly higher than the mean basal value. It is known that BGP synthesis is stimulated by 1,25 (OH)₂D₃ and that serum BGP is a specific marker of bone formation; therefore, it is possible that the low basal levels of osteocalcin we observed were related to the low serum 1,25(OH)₂D concentrations reported in osteoporotic women and that the increase in BGP levels observed under 1,25(OH)₂D₃ treatment was a consequence of osteoblast stimulation.     

Elevated serum pro-MMP2 levels in patients with stage IV thymoma

Abstract. Purpose: There is increasing evidence that matrix metalloproteinases (MMPs) play important roles in tumor invasion and metastasis. Using a one-step sandwich enzyme immunoassay, we investigated whether serum pro-MMP2 levels could be predictors of the development and extension of thymoma. Methods: The subjects of this study were 33 patients with thymoma and 26 patients with nonmalignant thoracic disease. Results: Serum pro-MMP2 levels were elevated in patients with stage IV thymoma (938.6 ± 80.2 ng/ml) compared with those in the controls (P= 0.03). Patients with stage IVb thymoma had significantly higher serum pro-MMP2 levels than patients with other stages, being 1088.7 ± 440 ng/ml in stage IVb, 686.0 ± 74.0 ng/ml in stage I (P= 0.01), 685.8 ± 48.6 ng/ml in stage II (P= 0.01), and 691.7 ± 74.0 ng/ml in stage III (P= 0.02). Serum pro-MMP2 levels were elevated in patients with polygonal cell type thymoma compared with those with mixed cell type thymoma, being 823.1 ± 55.5 ng/ml vs 613.6 ± 59.9 ng/ml, respectively (P= 0.04). Using the reference limit of 850 ng/ml (mean ± 2SD) set from analyses in the control group, all patients who had pro-MMP2 levels below the cutoff level survived. On the other hand, four of nine patients who had an elevated pro-MMP2 level died from recurrence. Conclusion: Serum pro-MMP2 levels may serve as a marker that could be used as an indicator of distant metastases in thymoma. Elevated pro-MMP2 levels may be correlated with poor survival. Received: June 29, 2001 / Accepted: November 20, 2001     

Effects of the selective endothelin A (ET<Subscript>A</Subscript>) receptor antagonist Clazosentan on cerebral perfusion and cerebral oxygenation following severe subarachnoid hemorrhage – preliminary results from a randomized clinical series

Summary Objective. To study the effects of clazosentan, a new selective endothelin receptor subtype A antagonist, on cerebral perfusion and cerebral oxygenation following severe aneurysmal subarachnoid haemorrhage (aSAH). Methods. All 12 patients treated at our institution in the context of a phase IIa, multicenter, randomized trial on clazosentan’s safety and efficacy in reducing the incidence of angiographic cerebral vasospasm were included in this substudy. The phase IIa study (n = 34) consisted of two parts: a double-blind, randomized Part A (clazosentan 0.2 mg/kg/h versus placebo) and an open-label Part B (clazosentan 0.4 mg/kg/h for 12 h followed by 0.2 mg/kg/h) for patients with established vasospasm. In parallel to the phase IIa study protocol, which included assessment of vasospasm by angiography and transcranial Doppler sonography, we determined regional cerebral blood flow (rCBF), cerebrovascular resistance, and regional tissue oxygenation. Results. Cerebral perfusion was comparable between treatment groups during the early post-bleeding period (rCBF placebo, 22.6 ± 3.5 ml/100 g/min versus rCBF clazosentan, 23.9 ± 1.1 ml/100 g/min). By the time of control angiography (day 8 after aSAH), rCBF decreased by 50% in the placebo group (11.3 ± 6.7 ml/ 100 g/min) while it remained stable in the clazosentan group (23.5 ± 12.9 ml/100 g/min). During Part B of the study, all 3 patients who developed haemodynamically relevant vasospasm during placebo treatment, showed a sustained improvement in rCBF upon conversion to clazosentan. Conclusions. These preliminary data suggest that clazosentan reduces the extent of vasospasm-associated impairment of cerebral perfusion following aSAH. Furthermore, clazosentan may exert beneficial actions on overt vasospasm-associated hypoperfusion. The first two authors contributed equally to the study     

Effects of risedronate alone or combined with vitamin K2 on serum undercarboxylated osteocalcin and osteocalcin levels in postmenopausal osteoporosis

Risedronate decreases osteoporotic fracture incidence; however, its effects remain unclear in elderly osteoporotic patients. Vitamin K mediates carboxylation of osteocalcin (OC), and high undercarboxylated osteocalcin (ucOC) levels indicate vitamin K deficiency and increased osteoporotic fracture risk. We aimed to evaluate the effects of risedronate alone or combined with vitamin K₂ on serum ucOC, OC, and incidence of vertebral fractures in elderly osteoporotic patients. A total of 101 women with postmenopausal osteoporosis aged >60 years were randomly stratified into two groups—R group (n = 51), treated with risedronate alone; and R + K group (n = 50), treated with risedronate and vitamin K₂. Serum ucOC, OC and incidence of vertebral fractures were evaluated before treatment and at 6 and 12 months post-treatment. Decreased ucOC rates at 6 and 12 months were not significant between groups. However, at 6 and 12 months, decreased OC rates in the R group (p < 0.01 and 0.05, respectively) were significantly higher than in the R + K group, and ucOC/OC change rates in the R group (p < 0.05 and 0.001, respectively) were significantly lower than in the R + K group. Vertebral fracture incidence was not significantly different between the groups at 6 and 12 months. ucOC levels in patients with incident vertebral fractures were significantly higher than in patients without incident vertebral fractures in the R group at 6 months (p < 0.05). Although no significant difference was observed for ucOC decrease rate and incidence of vertebral fractures between treatments, ucOC levels in patients with incident vertebral fractures were significantly greater than in patients without when using risedronate alone.     

Comparison of effects of diode laser and CO<Subscript>2</Subscript> laser on human teeth and their usefulness in topical fluoridation

Various authors have reported more effective fluoridation from the use of lasers combined with topical fluoride than from conventional topical fluoridation. Besides the beneficial effect of lasers in reducing the acid solubility of an enamel surface, they can also increase the uptake of fluoride. The study objectives were to compare the action of CO₂ and GaAlAs diode lasers on dental enamel and their effects on pulp temperature and enamel fluoride uptake. Different groups of selected enamel surfaces were treated with amine fluoride and irradiated with CO₂ laser at an energy power of 1 or 2 W or with diode laser at 5 or 7 W for 15 s each and compared to enamel surfaces without treatment or topical fluoridated. Samples were examined by means of environmental scanning electron microscopy (ESEM). Surfaces of all enamel samples were then acid-etched, measuring the amount of fluoride deposited on the enamel by using a selective ion electrode. Other enamel surfaces selected under the same conditions were irradiated as described above, measuring the increase in pulp temperature with a thermocouple wire. Fluorination with CO₂ laser at 1 W and diode laser at 7 W produced a significantly greater fluoride uptake on enamel (89 ± 18 mg/l) and (77 ± 17 mg/l) versus topical fluoridation alone (58 ± 7 mg/l) and no treatment (20 ± 1 mg/l). Diode laser at 5 W produced a lesser alteration of the enamel surface compared to CO₂ laser at 1 W, but greater pulp safety was provided by CO₂ laser (ΔT° 1.60° ± 0.5) than by diode laser (ΔT° 3.16° ± 0.6). Diode laser at 7 W and CO₂ laser at 2 W both caused alterations on enamel surfaces, but great pulp safety was again obtained with CO₂ (ΔT° 4.44° ± 0.60) than with diode (ΔT° 5.25° ± 0.55). Our study demonstrates that CO₂ and diode laser irradiation of the enamel surface can both increase fluoride uptake; however, laser energy parameters must be carefully controlled in order to limit increases in pulpal temperature and alterations to the enamel surface.     

Impaired gamma carboxylation of osteocalcin in elderly women with type II diabetes mellitus: relationship between increase in undercarboxylated osteocalcin levels and low bone mineral density

We conducted a cross-sectional examination of the role of serum vitamin K levels as they relate to bone metabolism in elderly women with type II diabetes mellitus (DM). Eighty-five elderly women with type II DM were enrolled. Three fractions of vitamin K, phylloquinone (PK), menaquinone 4 (menatetrenone; MK 4), and menaquinone 7 (MK 7), along with undercarboxylated osteocalcin (UcOC), intact osteocalcin (IOC), urinary deoxypyridinoline (udpd), urinary type I collagen N-telopeptide (NTx), and intact parathyroid hormone (IPTH) were measured. Bone mineral density was measured in the lumbar spine (LSBMD) by dual-energy X-ray absorptiometry (DXA), and T scores or Z scores were calculated. The patients were divided into two groups by T score, under –2.5 (osteoporotic group) and over –2.5 (non-osteoporotic group). UcOC levels in osteoporotics patients were significantly higher than those in the non-osteoporotic group (3.09 ± 3.94 vs 1.82 ± 1.76ng/ml, P = 0.02). The correlation between Z score and logarithmic UcOC/IOC levels in type II DM showed a negative trend (P = 0.07) and a significantly and negatively association with logarithmic NTx (r = –0.38; P = 0.001). In osteoporotic DM, the UcOC/IOC ratio was significantly correlated with the Z score (r = –0.61; P 0.05). Furthermore, logarithmic UcOC/IOC showed a negative correlation with logarithmic MK 7 (r = –0.50; P = 0.001). In conclusion, the reduction in LSBMD in elderly women with type II DM may be associated, in part, with a defect in -glutamylcarboxylation by vitamin K.     

Serum concentrations of carboxylated osteocalcin are increased and associated with several components of the polycystic ovarian syndrome

Intriguing studies suggest that osteocalcin (OC) and its carboxylated (Gla)/uncarboxylated form are involved in the regulation of insulin secretion and action. Additionally, advanced glycated end products (AGEs) directly regulate the secretion of these osteoblast-derived molecules. In polycystic ovarian syndrome (PCOS), among the pathophysiological aberrations, deregulation of insulin secretion and action as well as elevated AGEs levels have been demonstrated. In this study, we evaluated the serum levels of osteocalcin and Gla osteocalcin and their possible associations with metabolic, hormonal, and ultrasonographic components of PSOS: 97 women were studied, 50 PCOS patients and 47 controls, matched for age and body mass index (BMI). In each subject, the levels of bone metabolism markers have been evaluated, and metabolic and hormonal profiles as well as ovarian ultrasound were carried out. Osteocalcin (4.30 ± 1.74 vs. 6.20 ± 1.78 ng/ml, P < 0.0005) values were significantly lower, whereas Gla osteocalcin (37.93 ± 6.87 vs. 9.64 ± 8.21 ng/ml, P < 0.0005) and receptor activator for nuclear factor-κB ligand (0.54 ± 0.26 vs. 0.16 ± 0.15 pmol/l, P < 0.0005) values were significantly higher in PCOS subjects compared to the control group, independently of obesity. A significant association was disclosed between osteocalcin and Gla osteocalcin with androgens, insulin resistance, AGEs, and ovarian morphology. Receiver operating curve analysis revealed that Gla osteocalcin [AUC, 0.975 (95% CI, 0.93–1.00)] as well as AGEs are significant prognostic factors of PCOS [AUC, 0.986 (95% CI, 0.97–1.00)]. Lower osteocalcin and elevated serum levels of its carboxylated form are displayed in PCOS subjects and are associated with several PCOS components. These findings suggest a potential interaction between bone-derived markers and the metabolic/hormonal abnormalities observed in PCOS. However, the pathophysiological mechanisms and moreover the possible clinical implications require further investigation.     

Increase of Bone Resorption and the Parathyroid Hormone in Postmenopausal Women in the Long-term after Roux-en-Y Gastric Bypass

Background  The effects of Roux-en-Y Gastric Bypass (RYGB) on bone in the long-term remains unclear. We assessed bone metabolism and bone mineral density (BMD) 1 to 5 years after RYGB. Methods  We designed a retrospective cohort study in 26 postmenopausal women (58.0 ± 3.9 years old) with RYGB 3.5 ± 1.1 years before (body mass index (BMI) 29.5 ± 3.8 kg/m², presurgery 43.6 ± 5.5 kg/m²) and 26 nonoperated women (57.5 ± 4.7 years old, BMI 29.2 ± 4.1 kg/m²) matched by age and BMI. The main measures were BMD, serum carboxy telopeptide (CTx), total alkaline phosphatases (ALP), parathyroid hormone (PTH), 25-hydroxyvitamin D (25OHD), and ghrelin. Results  RYGB group, compared to nonoperated women, had higher CTx (0.71 ± 0.21 vs. 0.43 ± 0.15 ng/ml; P < 0.01) and PTH (68.3 ± 35 vs. 49.4 ± 16 pg/ml; P = 0.02). There were no differences between RYGB and nonoperated women in: calcium and vitamin D intake (759 ± 457 vs. 705 ± 460 mg/day; 176 ± 160 vs. 111 ± 86 UI/day), ghrelin (763 ± 336 vs. 621 ± 274 pg/ml), ALP (101 ± 22 vs. 94 ± 25 UI/l), 25OHD (18.8  ± 7.6 vs. 17.4 ± 5.9 ng/ml), lumbar spine BMD (1.059 ± 0.32 vs. 1.071 ± 0.207 g/cm²), or femoral neck BMD (0.892 ± 0.109 vs. 0.934 ± 1.1 g/cm²). Conclusions  RYGB is associated to high bone resorption and hyperparathyroidism prevalence in postmenopausal women in the long-term. This occurs independently of the intake of calcium, vitamin D status, or ghrelin and does not seem to affect BMD after RYGB.     

Influence of postoperative acute-phase response on angiogenesis and tumor growth: Open vs. laparoscopic-assisted surgery in mice

Inflammatory responses and tumor growth are increased after laparotomy compared with laparoscopy in some animal models. Proinflammatory cytokines interleukin-6 (IL-6) and interleukin-1 beta (IL-1β) upregulate the expression of vascular endothelial growth factor (VEGF). Our aim was to investigate the influence of postoperative inflammatory responses on angiogenesis and tumor growth. 5 Χ 10⁶ B51LiM cells were injected into the cecal wall of Balb/c mice. After 2 weeks, the animals were randomized into the following three groups: open cecectomy (OC), CO₂-laparoscopic-assisted cecectomy (LC), and helium-laparoscopic-assisted cecectomy (LH). On postoperative day 12, the mice were killed. Tumor load scores and weight were significantly greater after laparotomy than after laparoscopy. Serum IL-6 levels 6 hours after surgery (OC: 4157 ± 1297 pg/ml vs. LC: 2514 ± 1417 pg/ml vs. LH: 2255 ± 1714 pg/ml) and VEGF levels on postoperative day 12 (OC: 231 ± 125 pg/ml vs. LC: 45 ± 9 pg/ml vs. LH: 49 ± 8 pg/ml), measured by enzyme-linked immunosorbent assay, were significantly higher in the laparotomy group. Microvessel density was also significantly higher in the OC group (OC: 34.3 ± 11.5 vs. LC: 15.5 ± 12.5 vs. LH: 18.5 ± 11.9). There was a positive correlation between IL-6 and VEGF postoperative serum levels (rho = 0.67; P < 0.001). We concluded that increased systemic levels of proinflammatory cytokines and VEGF are associated with increased angiogenesis and tumor growth after laparotomy compared to laparoscopy in mice. Presented at the Fifty-Seventh Annual Sessions of the Owen H. Wangensteen Surgical Forum, The American College of Surgeons Clinical Congress, San Francisco, California, October 6–10, 2002; and published as an abstract in Journal ofthe American College of Surgeons 2002; 195:S69. Supported by an International Fellowship Grant from the American Society of Colon and Rectal Surgeons (M.P.) and by a Postdoctoral Grant (EX2001-35105008) from the Ministry of Education and Culture of Spain.     

Osteocalcin Gene Polymorphism is Related to Bone Density in Healthy Adolescent Females

Recently a polymorphism was found in the human osteocalcin gene, and its association with bone mass was investigated in healthy postmenopausal Japanese women. The osteocalcin gene allelic variant HH was found to be overrepresented in women with osteopenia. The purpose of this study was to investigate whether the previously demonstrated polymorphism of the osteocalcin gene was related to bone mineral density (BMD; g/cm²) or osteopenia in a group of 97 healthy Caucasian adolescent females (aged 16.9 ± 1.2 years, mean ± SD). BMD of the left humerus, right femoral neck, lumbar spine and total body was measured using dual-energy X-ray absorptiometry. The relation between the allelic variants and bone density was analyzed as presence or absence of the H allele. Presence of the H allele was found to be related to a lower BMD of the humerus (0.97 vs 1.02, p = 0.03). There was also a strong tendency towards significance at the femoral neck (p = 0.06) and total body (p = 0.11). Using a multiple linear regression and including physical activity, weight, height and years since menarche, presence of the H allele was found to be an independent predictor of humerus BMD (β=−0.21, p<0.05) and femoral neck BMD (β=−0.23, p<0.01). Using logistic regression, presence of the H allele was also independently associated with a 4.5 times increased risk of osteopenia (p = 0.03) in the whole group. Osteopenia was defined as at least 1 SD lower bone density than the mean for the whole group of at least one of the BMD sites measured. We have demonstrated that the osteocalcin HindIII genotype is independently related to bone density in healthy adolescent females. The present study also suggests that presence of the H allele is predictive of osteopenia at an early age. Received: 31 January 2000 / Accepted: 25 April 2000     

Effect of raloxifene on clinical fractures in Asian women with postmenopausal osteoporosis

Osteoporosis is becoming a major public health problem in Asian countries, with a rapid increase in osteoporotic fractures projected as urbanization increases, particularly in China. The purpose of this post hoc analysis was to assess the effects of 12 months of treatment with raloxifene on the incidence of clinical fractures in postmenopausal Asian women, compared to a placebo, by combining two independently designed studies (one Japanese study and one Chinese study). A total of 488 women, 284 in Japan and 204 in China were included in the analysis. Baseline characteristics (mean ± SD) for the Japanese and Chinese women were: age, 64.8 ± 6.3 years and 65.3 ± 6.0 years; body mass index, 21.8 ± 2.8 kg/m² and 23.0 ± 2.9 kg/m²; and prevalent vertebral fractures, 26.4% and 13.7%, respectively. In both studies, the clinical vertebral and nonvertebral fractures were confirmed by radiographs or clinical reports at a central research facility. From the two combined studies, the incidence of new clinical vertebral fractures was significantly lower in the raloxifene 60 mg/day (RLX60) group (0 out of 194, P = 0.01) and in the pooled raloxifene group (those taking 60 mg/day and those taking 120 mg/day) (0 out of 289, P = 0.002), compared with the placebo group (7 out of 199, 3.5%). The pooled raloxifene group, as well as the RLX60 group, also had a significantly lower incidence of any new clinical fracture (P = 0.001 and P = 0.01, respectively) compared to the placebo group. In conclusion, raloxifene treatment at 60 mg/day for 1 year resulted in a significant reduction in the risk of new clinical vertebral fractures and any new clinical fracture in postmenopausal Asian women with osteoporosis.     

High Prevalence of Hypovitaminosis D among Free-Living Postmenopausal Women Referred to an Osteoporosis Outpatient Clinic in Northern Italy for Initial Screening

To establish the prevalence of hypovitaminosis D among free-living postmenopausal women referred to an osteoporosis outpatient clinic in Northern Italy, we evaluated 25-hydroxyvitamin D (25(OH)D) levels in 570 postmenopausal women who had been consecutively referred to our clinic in the 12 months beginning October 1995. Parathyroid hormone (PTH), serum calcium (Ca), creatinine (Cr) and osteocalcin (OC), urinary calcium (Ca24h) and creatinine (Cr24h), and the bone mineral density of the lumbar spine (LBMD) and femur (FBMD) were also measured. 1,25-Dihydroxyvitamin D (1,25(OH)₂D) concentrations were measured in 23 women. All women had normal electrolyte serum concentrations and kidney function. Mean ± SD 25(OH)D concentration was 18.3 ± 8.3 ng/ml. A significant (p<0.001) seasonal variation was seen for both 25(OH)D and PTH. Women were divided into two groups based on their vitamin D status: low vitamin D status (25(OH)D <12 ng/ml, n= 161, 28%) and normal vitamin D status (25(OH)D ≥12 ng/ml, n= 409, 72%). Hypovitaminosis D was found in 38.5% of all the women in the time period December–May and in 12.5% in the other half-year; among women >70 years old 51% had hypovitaminosis D in the time period December–May and 17% in the other half-year. PTH was significantly (p<0.05) increased, and Ca24h, OC and FBMD significantly (p<0.05) decreased in women with hypovitaminosis D. 1,25(OH)₂D positively correlated with 25(OH)D (p<0.0001), but did not correlate with PTH, age or creatinine clearance. In conclusion, hypovitaminosis D is an important, underestimated problem in Italian free-living postmenopausal women referred to an outpatient osteoporosis clinic. Received: 9 February 1998 / Accepted: 8 July 1998     

IGF-1 as an early marker for low bone mass or osteoporosis in premenopausal and postmenopausal women

To find out which of the following parameters—serum levels of insulin-like growth factor 1 (IGF-1), osteoprotegerin (OPG), leptin, osteocalcin (OC), and urinary excretion of N-terminal telopeptide of type I collagen (NTx), can be used as an early marker for osteopenia/osteoporosis in women diagnosed by dual-energy X-ray absorptiometry (DXA), 282 premenopausal and 222 postmenopausal women aged 20–75 years were investigated by the measurement of bone mineral densities (BMDs) at lumbar spine (LS) and femoral neck (FN) by DXA, together with serum concentrations of IGF-1, OPG, leptin, OC, and urinary NTx. The characteristics of the earliest marker(s) were tested with the receiver operating characteristic (ROC) analysis. The area under the curve (AUC), sensitivity, and specificity parameters were determined. It was revealed that serum levels of IGF-1 and leptin changed the earliest, with both markers significantly decreasing (P < 0.0001) or increasing (P = 0.020), respectively, at age 30. However, in ROC analysis, IGF-1 was the only early parameter that had the capacity to differentiate the low bone mass/osteoporosis women from the normal ones (P < 0.0001). If the serum level of IGF-1 at 1.5 SD below its peak was adopted as a cutoff point, it could identify women with low bone mass/osteoporosis with a sensitivity of 73% and specificity of 67%. In the premenopausal women subgroup analysis, the low bone mass women (30/282, 10.6%) were older (38.2 ± 1.7 vs. 34.5 ± 0.5 years; P = 0.026), with lower serum levels of IGF-1 (215.1 ± 22.4 vs. 278.8 ± 9.4 ng/ml; P = 0.02) and less lean mass (33.1 ± 0.6 vs. 34.8 ± 0.2 kg; P = 0.010) than the normal ones. After controlling for age, the serum level of IGF-1 had a weak, but still significant, positive correlation with lean mass (r = 0.17, P < 0.001). In conclusion, measurement of serum IGF-1 in young women may help in the early identification of those at risk for developing low bone mass and osteoporosis.     

Enhancement of t-PA Induced Fibrinolysis with Laser Energy: In-Vitro Observations

The solid-state, pulsed-wave, holmium:YAG laser operates within strong water absorption peaks at the mid-infrared optical wavelength. This laser has been shown to be capable of inducing a mechanical, photoacoustic dissolution of fibrin, a major constituent of thrombi. It is not known whether this laser's energy combined with pharmacologic therapy can enhance the rate of fibrinolysis. The aims of this study were (1) to test the hypothesis that mid-infrared laser emission can enhance tissue-type plasminogen-activator (t-PA) mediated fibrinolysis and (2) to test the combined effect of these two methods of fibrinolysis on fibrin clots varying in age. Three in vitro experimental protocols were used. (1) Fibrin clots were treated with 116 000 IU t-PA for 1, 6 and 12 h, respectively, and then exposed to mid-infrared laser energy (solid-state, pulsed-wave, holmium:YAG, 2.1 μm wavelength 250 ms pulse length, 5 Hz repetition rate, 500 mJ/pulse (33 J/cm²)). (2) Fibrin gels layered with t-PA were exposed to either 25, 50, 75 or 100 J laser energy. t-PA was then allowed to interact with the lased gels for an additional 4 h. (3) The effects of varying clot age (1, 4 or 8 h) on laser (75 J) augmentation of t-PA induced fibrinolysis were tested. Each experimental protocol had control gels and following each experimental manoeuvre, 20 μl of the plasmin inhibitor ε-amino-n caproic acid was added and fibrin degradation products (FDPs), an indicator of fibrinolysis, were measured by latex agglutination. In fibrin clots exposed to t-PA for 6 h, the addition of laser energy significantly increased FDPs released (t-PA alone 40±0 μg/ml, laser plus t-PA 160±0 μg/ml, p<0.001). For gels exposed to t-PA for 12 h, addition of laser energy resulted in complete dissolution of the clot (FDPs with t-PA alone 160±0 μg/ml vs. laser plus t-PA>300 μg/ml, p=0.001). The rise in FDPs was significantly greater with 75 J of laser energy compared to 25 J (160±0 μg/ml vs. 80±0 μg/ml, p=0.0001), however, energy levels greater than 75 J did not further increase the amount of FDPs indicating a plateau phenomenon in dose–response relationship. t-PA had a decreased fibrinolytic effect on 4 and 8 h-old clots (FDPs of 60±20 μg/ml and 30±10 μg/ml, respectively). Laser energy reversed this trend and enhanced fibrinolysis in both 4 and 8 h-old clots. In 4 h-old clots, laser plus t-PA resulted in FDP release of 160±0 μg/ml compared to 60±20 μg/ml for t-PA alone (p=0.007). In 8 h-old clots, FDP release with laser plus t-PA was 160±0 μg/ml compared to 30±10 μg/ml with t-PA alone (p=0.0004). It was concluded that in vitro application of mid-infrared laser energy significantly enhances fibrinolysis in fibrin clots initially treated by t-PA. The in vitro interaction between mid-infrared laser and t-PA is energy dependent, however, at energy levels exceeding 75 J there is a plateau phenomenon in dose–response relationship. This wavelength photoacoustic energy also augments the decreased response of ageing clots to t-PA.     

Infrared analysis of bones in magnesium-deficient rats treated with vitamin K<Subscript>2</Subscript>

In this study, we compared the effects of vitamin K₂ menatetrenone on bone mechanical properties in rats fed a low-magnesium (Mg) diet. In addition, the mechanism of bone quality was examined using Fourier transform infrared imaging (FTIRI). Thirty 4-week-old male Wistar rats were divided into three groups: intact, low-Mg-control, and low-Mg-MK-4 groups. Rats in the low-Mg groups were given a diet containing 6 mg/100 g Mg (intact, 90 mg/100 g). After an 8-week-treatment, the cortical bone mineral content (CtBMC), outer perimeter, and endo perimeter of the femoral diaphysis in the low-Mg-control group were significantly higher, while the maximum load (ML) and elastic modulus (EM) were 81% and 50% of those in the intact group, respectively (respectively, P < 0.05). In the low-Mg-MK-4 group, ML and EM were significantly higher than in the low-Mg-control group (P < 0.05), with no differences in CtBMC. The mineral/matrix ratios for the periosteal and central regions in the low-Mg-control group were 162% and 120% of those in the intact group (both, P < 0.05), respectively. MK-4 significantly inhibited these increases (P < 0.05). We found that the mineral/matrix ratios for the periosteal region of the femoral diaphysis were negatively correlated with EM, suggesting that an increase in the mineral/matrix ratio may be involved in the reduction of EM and that MK-4 may improve EM by improving the mineral/matrix ratio.     

The Prognostic Significance of Total Lymph Node Harvest in Patients with T<Subscript>2–4</Subscript>N<Subscript>0</Subscript>M<Subscript>0</Subscript> Colorectal Cancer

In patients with radically resected colorectal carcinoma, lymph node involvement is particularly important for a good prognosis and adjuvant therapy. The number of such lymph node recoveries is still controversial, with recommendations ranging from 6 to 17 nodes. The aim of this study is to determine if a specified minimum number of lymph nodes examined per surgical specimen can have any effect on the prognosis of patients who have undergone curative resection for T_2–4N₀M₀ colorectal carcinoma. Between September 1999 and January 2005, a total of 366 patients who underwent radical resection for T_2–4N₀M₀ colorectal carcinoma were retrospectively analyzed in a single institution. All specimen segments were fixed, with node identification performed by sight and palpation. We excluded 186 patients who received postoperative adjuvant chemotherapy via oral or intravenous transmission to prevent possible chemotherapeutic effects on patients’ prognosis; therefore, a total of 180 patients with T_2–4N₀M₀ colorectal carcinoma were enrolled into this study. After the pathological examination, a mean of 12 lymph nodes (range 0–66) was harvested per tumor specimen. No postoperative relapse was found in this group, where the number of examined lymph nodes was 18 or more. Univariate analysis identified the size of the tumor, depth of invasion, grade of tumor, and number of examined lymph nodes, which were significantly correlated with postoperative relapse (all P < 0.05). Meanwhile, both the depth of tumor invasion and the number of harvested lymph nodes were independent predictors for postoperative relapse (P < 0.05). The 5-year overall survival rate of T_2–4N₀M₀ colorectal carcinoma patients who had 18 or more lymph nodes examined was significantly higher than those who had less than 18 nodes examined (P = 0.015). Nodal harvest in patients undergoing radical resection for colorectal carcinoma was highly significant in the current investigation. Our results suggest that harvesting and examining a minimum of 18 lymph nodes per surgical specimen might be taken into consideration for more reliable staging of lymph node-negative colorectal carcinoma.