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BACKGROUND: Smoking is a recognized risk factor for osteoporosis. Trabecular bone score (TBS) is a novel texture parameter to evaluate bone microarchitecture. TBS and their main determinants are unknown in active and former smokers. OBJECTIVE: To assess TBS in a population of active or former smokers with and without Chronic Obstructive Pulmonary Disease (COPD) and to determine its predictive factors. METHODS: Active and former smokers from a pulmonary clinic were invited to participate. Clinical features were recorded and bone turnover markers (BTMs) measured. Lung function, low dose chest Computed Tomography scans (LDCT), dual energy absorptiometry (DXA) scans were performed and TBS measured. Logistic regression analysis explored the relationship between measured parameters and TBS. RESULTS: One hundred and forty five patients were included in the analysis, 97 (67.8%) with COPD. TBS was lower in COPD patients (median 1.323; IQR: 0.13 vs 1.48; IQR: 0.16, p = 0.003). Regression analysis showed that a higher body mass index (BMI), younger age, less number of exacerbations and a higher forced expiratory volume-one second (FEV1%) was associated with better TBS (ß = 0.005, 95% CI:0.000-0.011, p = 0.032; ß = -0.003, 95% CI:-0.007(-)-0.000, p = 0.008; ß = -0.019, 95% CI:-0.034(-)-0.004, p = 0.015; ß = 0.001, 95% CI:0.000-0.002, p = 0.012 respectively). The same factors with similar results were found in COPD patients.

Context Bone loss is accelerated in the late perimenopause and early menopause. The date of the final menstrual period cannot be stated until 1 year after it has ended, and at that time, most of the rapid bone loss phase will have elapsed. Therefore, early detection of bone loss is crucial. Objectives To evaluate the utility of bone turnover markers (BTM) to identify the women who are more likely to lose more bone mass during the transition to menopause and quantify the loss of bone quality measured by trabecular bone score (TBS). Design, patients and setting Sixty-four healthy premenopausal women, mean age between 44 and 57 years old, were enrolled and followed up for 5 years. Clinical features, lifestyle, bone densitometry, TBS and BTM (CTX, P1NP and osteocalcin) were measured at baseline and follow-up. Results All women had densitometrically normal bone at the time of enrolment. After 5 years, 48.4% had normal bone mineral density, 45.8% low bone mass and 6.3% osteoporosis. Women with osteopenia/osteoporosis at follow-up had higher CTX and P1NP at enrolment compared with women with densitometrically normal bone. The areas under the curve for the prediction of low bone mass or osteoporosis were 0.69 (P = 0.011) for P1NP, 0.69 for CTX (P = 0.013) and 0.77 (P 0.001) for OC. A significant correlation was found between P1NP increase after 5 years and the decrease in lumbar bone density (r = -0.383, P = 0.002). At baseline, 7 (10.9%) women had deteriorated microarchitecture (TBS < 1.3). Three of these women developed osteoporosis and four osteopenia at follow-up. Conclusions Women with higher P1NP and CTX and lower TBS at baseline had lower BMD in the transition to menopause suggesting these novel tools could have potential use in identifying women at high risk of rapidly decreasing bone mass.

The most common cause of organic fasting hypoglycemia in adults is the presence of an insulin-producing pancreatic adenoma, but when high insulin levels are not found, the differential diagnosis is challenging. Misdiagnosis can lead to an unnecessary pancreatectomy. Insulin concentrations may be low in some cases despite a clinical history suggestive of insulinoma. In these cases, a proinsulinoma should be suspected, although the rarity of this condition requires an extensive workup before reaching a final diagnosis. We describe an unusual case of a 38-year-old man with a severe hypoglycemic syndrome due to a proinsulin-secreting pancreatic adenoma. Insulin was measured by the specific assay and suppressed under the lower detection limit during fasting hypoglycemia. Serum proinsulin and C-peptide levels were abnormally elevated, and further tests revealed an islet cell tumor. The tumor was surgically removed, relieving the fasting hypoglycemia. Histopathological study showed a conventional well-differentiated neuroendocrine tumor with high immunoreactivity against proinsulin and with lesser intensity against insulin. Interestingly, GS-9A8 antibody clone used for immunostaining proinsulin did not cross-react with human insulin or C-peptide, providing an unbiased picture of proinsulin secretion. The resolution of symptoms, the fall of proinsulin concentrations after tumor removal and the histopathology study confirmed the diagnosis of proinsulinoma

BACKGROUND/OBJECTIVES: The validation of effective screening tools for the identification of patients with subclinical myocardial remodelling is a major clinical need. Thus, we explored the associations of circulating biomarkers of cardiomyocyte injury and stress with subclinical cardiac remodelling and dysfunction, and with biomarkers reflecting collagen turnover. METHODS: We randomly recruited 727 subjects from a general population (51.2% women; mean age 51.3 years). Measurements included echocardiographic left atrial (LA) and left ventricular (LV) structure and function, quantification of high sensitivity cardiac Troponin T (hs-cTnT), NT-proBNP, and biomarkers of collagen types I and III turnover. RESULTS: In unadjusted and adjusted analyses, the prevalence of LA enlargement (LAE), LV hypertrophy (LVH) and LV diastolic dysfunction (LVDD) increased with higher hs-cTnT (P ¿ 0.031). NT-proBNP was independently associated with LVDD (P=0.009). Both biomarkers combined yielded significant integrated discrimination and net reclassification improvements (P ¿ 0.014 and P ¿ 0.009, respectively) for LAE, LVH and LVDD, over the conventional risk factors, and were independently and positively associated with biomarkers of collagen type I turnover. In a sensitivity analysis, after excluding participants with previous cardiac diseases, our findings remained consistent. CONCLUSIONS: Our population-based study suggested that subclinical LV and LA remodelling were associated with hs-cTnT, and that, in combination with NT-proBNP, hs-cTnT showed incremental diagnostic utility over the conventional risk factors. Both biomarkers were associated with biomarkers of collagen type I turnover. Thus, biomarkers of cardiomyocyte microinjury and hemodynamic stress may stimulate fibrosis-related mechanisms and facilitate the diagnosis of subclinical LA and LV remodelling and dysfunction in the general population.

BACKGROUND & AIMS: Radioembolization may rarely induce liver disease resulting in a syndrome that is similar to veno-occlusive disease complicating bone marrow transplantation where inflammation, endothelial cell activation and thrombosis are likely involved. We hypothesized that similar mechanisms could be implicated in radioembolization-induced liver disease (REILD). Moreover, lobar radioembolization may induce hypertrophy of the non-treated hemiliver most probably by inducing liver regeneration. METHODS: In patients with hepatocellular carcinoma, we prospectively studied serum levels of markers of liver regeneration, oxidative stress, pro-inflammatory pathways, endothelial activation and coagulation parameters over 2 months after radioembolization. RESULTS: Although REILD did not occur among 14 treated patients, a decrease in effective liver blood flow was observed. Radioembolization was followed by a persistent increase in pro-inflammatory (interleukin 6 and 8) and oxidative stress (malondyaldehide) markers, an induction of endothelial injury markers (vW factor and PAI-1) and an activation of the coagulation cascade (factor VIII, PAI-1, D-Dimer) as well as a significant increase in factors related to liver regeneration (FGF-19 and HGF). CONCLUSION: Radioembolization activates liver regeneration, produces oxidative stress, activates inflammatory cytokines and induces endothelial injury with partial activation of the coagulation cascade. These findings may have implicati

Context: Bone turnover markers (BTMs) may identify changes in bone remodeling within a relatively short time interval before changes in bone mineral density can be detected. New markers such as osteoprotegerin, receptor activator of nuclear factor-B ligand, and sclerostin have emerged, but there is little information about their potential use in clinical practice. Design, Patients, and Setting: We performed an observational prospective study in pre-and postmenopausal ambulatory women (n =72 and n =152, respectively). Intervention: Postmenopausal women with osteoporosis (n =18) were treated with risedronate and calcium. Womenfilled out a questionnaire and underwent bone mineral density measurement using dual-energy x-ray absorptiometry at the time of enrollment and after 1 year of follow-up. BTMs were measured at baseline, at 6 months, and after 1 year. Results: Increased levels of N-terminal propeptide of type 1 procollagen (P1NP) and beta-type I collagen telopeptides (CTXs) were associated with low bone mineral density in the premenopausal (P =.02 and P =.04, respectively) and postmenopausal (P =.03 and P =.02) groups. The best analytical performance to diagnose osteoporosis was for = -CTX, osteocalcin, and P1NP, with areas under the curve of 0.70 (P =.005), 0.64 (P =.048), and 0.71 (P =.003). A significant decrease was found in P1NP, osteocalcin, tartrate-resistant acid phosphatase-5b, =-CTX, and bone alkaline phosphatase after 1 year of treatment (all P =.05). Conclusions: Our data suggest that measurement of beta beta-CTX and P1NP shows adequate analytical performance and could potentially be included in algorithms for the screening of osteoporosis. Furthermore, these two markers, along with osteocalcin and tartrate-resistant acid phosphatase5b, are useful to monitor the response to risedronate.

Background: The relationship between serum biomarkers and clinical expressions of COPD is limited. We planned to further describe this association using markers of inflammation and injury and repair. Methods: We studied lung function, comorbidities, exercise tolerance, BODE index, and quality of life in 253 COPD patients and recorded mortality over three years. Serum levels of Interleukins 6,8 and 16, tumor necrosis factor alpha (TNF alpha) [inflammatory panel], vascular endothelial growth factor (VEGF), and matrix metalloproteinase 9 (MMP-9)[injury and repair panel] and pulmonary and activation-regulated chemokine (PARC/CCL-18) and monocyte chemotactic protein 1 (MCP-1/CCL2) [chemoattractant panel] were measured. We related the pattern of the biomarker levels to minimal clinically important differences (MCID) using a novel visualization method [ObServed Clinical Association Results (OSCAR) plot]. Results: Levels of the inflammatory markers IL-6, TNF alpha were higher and those of injury and repair lower (p < 0.01) with more advanced disease (GOLD 1 vs. 4). Using the OSCAR plot, we found that patients in the highest quartile of inflammatory and lowest quartile of injury and repair biomarkers level were more clinically compromised and had higher mortality (p < 0.05). Conclusions: In COPD, serum biomarkers of inflammation and repair are distinctly associated with important clinical parameters and survival.

Complejo de glucoproteínas asociadas con la distrofina, distrofias musculares de Duchenne y Becker, técnicas bioquímicas diagnósticas de las distrofias musculares de Duchenne y Becker, otras distrofias.