430 research outputs found
Respiratory parameters at varied altitudes in intermittent mining work
Objectives: Workers in the mining industry in altitude are subjected to several risk factors, e.g., airborne silica and low barometric pressure. The aim of this study has been to assess the risks for this work category, evaluating single risk factors as airborne silica, altitude and work shift, and relating them with cardiovascular and ventilatory parameters. Material and Methods: Healthy miners employed in a mining company, Chile, working at varied altitudes, and subjected to unusual work shifts, were evaluated. Cardiovascular and respiratory parameters were investigated. Exposure to airborne silica was evaluated and compared to currently binding exposure limits. Results: At varied altitudes and work shifts, alterations emerged in haemoglobin, ventilation and respiratory parameters, related to employment duration, due to compensatory mechanisms for hypoxia. Haemoglobin increased with altitude, saturation fell down under 90% in the highest mines. The multiple linear regression analysis showed a direct relationship, in the higher mine, between years of exposure to altitude and increased forced vital capacity percent (FVC%), and forced expiratory volume in 1 s (FEV1). An inverse relationship emerged between forced vital capacity (FVC) and years of exposure to airborne silica. In the workplace Mina Subterrànea (MT-3600), statistically significant inverse relationship emerged between the Tiffeneau index and body weight. Conclusions: The working conditions in the mining industry in altitude appeared to be potentially pathogenic; further investigations should be realized integrating risk assessment protocols even in consideration of their undeniable unconventionality
Remote Zones Air Quality. Persistent Organic Pollutants: Sources, Sampling and Analysis
Concern about air quality has been rising since the Industrial Revolution and the so-called “Second Industrial Revolution” characterized by internal combustion engine, electrical technology and above all synthesis of new chemicals. Since then mankind has been facing the consequences of its thoughtless release of pollutants in atmosphere, consequences as reducing smog, acid rains and photochemical smog. Notwithstanding the seriousness of single episodes, these were local, or at most regional, phenomena. Nowadays, the variety of pollutants and the extent of pollution is greater than even in history, and air pollution problems are reaching up to global scale. In the last decades, it was established that manmade chemicals, such as polychlorinated biphenyls, chlorofluorocarbons and volatile chlorinated hydrocarbons, were present even in the remotest zones of the Earth, according to their volatility and half-life. This evidence stimulated the scientific community to monitor air quality of remote zones, areas considered a short time ago as uncontaminated. This chapter deals with different sampling and analysis techniques for persistent organic pollutants (POPs) in the atmosphere of remote zones. Features, sources and environmental fate of POPs are presented in the first section. The second section focuses on logistic and experimental difficulties connected to surveys in remote zones. The third section focuses on recent developments and improvements concerning sampling and analytical methods for POPs in air. The most significant findings on the presence of POPs in remote zones are shown in the last section
Indoor Air Quality. Volatile Organic Compounds: Sources, Sampling and Analysis
Since the 70s research has found in Europe and in the United States that individuals spend between 70 and 90% of their time indoors. Health studies have found that exposures to a variety of air pollutants indoors can be substantially higher than outdoors, even in urban environment. Volatile Organic Compounds (VOCs) are often more important, depending by their continue emission from many sources and their diffusion properties. In order to evaluate the occupants discomfort and health effects and developing guidelines and standards, Indoor Air Quality (IAQ) assessment and control is an essential step; IAQ assessment will complain: Sources, Sampling Methods, Analysis and Data Meanin
Where Wnts Went: The Exploding Field of Lrp5 and Lrp6 Signaling in Bone
Wnt signaling has emerged as a central regulator of skeletal modeling and remodeling. Loss- or gain-of-function mutations in two Wnt co-receptors, Lrp5 and (more recently) Lrp6, have drawn attention to the importance of the Wnt pathway in bone biology. This review summarizes our current understanding of how the Wnt pathway operates on bone and the implications this has for skeletal physiology and drug discovery. Over the past 9 yr, rapid advances have been made in our understanding of the cellular targets for Wnt signaling and of the important regulatory molecules in this metabolic pathway. Both canonical and noncanonical signaling pathways seem to be important for mediating the effects of Wnt in bone. A rapidly expanding catalog of genetically engineered mice has been used to establish the importance of downstream effector molecules (such as β-catenin) in the Wnt pathway, as well as the critical role of endogenous inhibitors of Wnt signaling (such as Dkk1 and sclerostin) in bone metabolism. Indeed, regulation of sclerostin in osteocytes is emerging as an important final pathway for regulating bone anabolism in response to diverse trophic stimuli, from mechnotransduction to the anabolic actions of PTH. From the outset, it had been assumed that the effects of Wnt signaling in bone were caused by direct actions in osteoblast precursors, osteoblasts, and osteocytes. However, startling recent findings have challenged this view and suggest that a key target, at least in mice, is the duodenal enterochromaffin cell. There, Wnt signaling transduced by Lrp5 regulates serotonin synthesis, which acts in an endocrine fashion to regulate bone cell metabolism. It will take time to reconcile this new information with the considerable body of information we already have regarding the actions of Wnt in bone. The Wnt pathway has rapidly emerged as a therapeutic target for drug discovery. Neutralizing antibodies and small-molecule inhibitors of endogenous Wnt inhibitors have shown early promise as bone anabolic agents. However, given the central role of the Wnt pathway in regulating growth and development in extraskeletal tissues, as well as our still rudimentary understanding of how this signaling cascade actually affects bone metabolism, considerable work will be needed to ensure the safety of these new therapies
Bloggifier: un framework para la incorporación transparente de funcionalidad de blogging en aplicaciones enterprise
El objetivo de esta tesis, viendo la relevancia de los Blogs y bajo la hipótesis de que se los puede integrar con aplicaciones enterprise, es desarrollar una estrategia general más herramientas para agregar funcionalidad de blogs de manera transparente a una aplicación Enterprise existente, modificándola lo menos posible.Sólo se dispone de la presentación de la tesis.Facultad de Informátic
Torus Palatinus: A New Anatomical Correlation with Bone Density in Postmenopausal Women
The observation that subjects who have a striking oral exostosis, called torus palatinus, also tended to have normal or high bone densities prompted us to examine an unselected population referred for bone density assessment for a possible correlation with torus palatinus. Subjects referred from community physicians had a visual examination of the open mouth to estimate the size of any torus palatinus (0 for none/ trace to 5 for very large) before undergoing a bone density measurement by dual energy x-ray absortiometry. Bone density T- and z-scores were correlated with the size of each subject’s torus palatinus. Torus size groups were also correlated with other variables affecting bone density. About 20% of 370 postmenopausal female subjects,\u3e90% Caucasian, had a moderate to large torus palatinus. Regression correlations for torus size were modest, but significantly related to T- and z-scores of lumbar vertebrae and left hip (P \u3c 0.01 for each). Differences due to medication, body mass index, smoking, parity, and several other factors that affect bone density did not diminish the relation to torus size. This study shows a small, but significant, positive relation for postmenopausal, Caucasian women between bone mineral density and torus size after controlling for several variables known to affect bone density were examined. Torus prominence, in association with other factors, can be considered in decisions for testing bone density in otherwise normal postmenopausal women
OR13-1 Burosumab Improves the Biochemical, Skeletal, and Clinical Symptoms of Tumor-Induced Osteomalacia Syndrome
Tumor-induced Osteomalacia (TIO) and Epidermal Nevus Syndrome with osteomalacia (ENS) are rare conditions in which ectopic production of FGF23 by tumor (TIO) and bone (ENS) lead to renal phosphate wasting, impaired 1,25(OH)2D synthesis, osteomalacia, fractures, weakness, fatigue and decreased mobility. In an ongoing open-label Phase 2 study (NCT02304367), 17 adults were enrolled and treated with burosumab, a fully human monoclonal antibody against FGF23. Key endpoints were change in serum phosphorus and osteomalacia as assessed from trans-iliac crest bone biopsies. The per protocol (PP) analysis included 14/17 subjects who received 0.3-2.0 mg/kg burosumab every 4 weeks (W). Three subjects were excluded: 1 received subthreshold dosing (0.3 mg/kg at Day 0 and 0.15 mg/kg at W8, W32, and W72); 2 were diagnosed with X-linked hypophosphatemia post-enrollment. Ten subjects in the PP group had paired bone biopsies at baseline and W48. Mean ± SE histomorphometric values for the 8/10 subjects with osteomalacia at baseline were 20.4 ± 4.2 µm for osteoid thickness (OT), 23.0 ± 7.2% for osteoid volume/bone volume (OV/BV), and 66.1 ± 10.6% for osteoid surface/bone surface (OS/BS); baseline median (Q1, Q3) for mineralization lag time (MLT) was 1672 (1102, 2929) days. At W48, histomorphometric indices improved as shown by mean percentage changes in OT (37%), OV/BV (40%), OS/BS (-5%), and MLT (median percentage change -78%). Serum phosphorus, fatigue, and physical functioning are reported for the PP group. Mean (SD) serum phosphorus was 1.5 (0.3) mg/dL at baseline and 2.6 (0.8) mg/dL when averaged across the mid-point of the dose interval through W24. After W24, serum phosphorus, assessed only at the end of the dose interval, maintained this increase through W72. Mean (SD) Global Fatigue Score decreased from 5.3 (2.8) at baseline to 3.6 (2.9) at W48 (p=0.020) and to 3.3 (2.7) at W72 (p=0.004). The SF-36 mean (SD) physical component summary score increased from 34 (11) at baseline to 39 (10) at W48 (p=0.059) and to 42 (10) at W72 (p=0.003). Mean (SD) vitality score increased from 41 (14) to 47 (12) at W48 (p=0.075) and to 49 (12) at W72 (p=0.012). The mean (SD) number of sit-to-stand repetitions increased from 6.9 (4.0) at baseline to 8.6 (4.2) at W48 (n=10; p=0.004). By W72, all 17 subjects had ≥1 adverse event (AE). There were 13 serious AEs in 6 subjects, none were considered drug-related. Tumor progression occurred only in subjects with a history of tumor progression prior to enrollment. One subject discontinued treatment prior to W48 to treat tumor progression with chemotherapy. There was 1 death, considered unrelated to treatment. In adults with TIO Syndrome, burosumab was associated with improvements in serum phosphorus, osteomalacia, mobility, quality of life, and reductions in fatigue
Pharmacokinetics and pharmacodynamics of a human monoclonal anti‐FGF23 antibody (KRN23) in the first multiple ascending‐dose trial treating adults with X‐linked hypophosphatemia
In X-linked hypophosphatemia (XLH), serum fibroblast growth factor 23 (FGF23) is increased and results in reduced renal maximum threshold for phosphate reabsorption (TmP), reduced serum inorganic phosphorus (Pi), and inappropriately low normal serum 1,25 dihydroxyvitamin D (1,25[OH]2D) concentration, with subsequent development of rickets or osteomalacia. KRN23 is a recombinant human IgG1 monoclonal antibody that binds to FGF23 and blocks its activity. Up to 4 doses of KRN23 were administered subcutaneously every 28 days to 28 adults with XLH. Mean ± standard deviation KRN23 doses administered were 0.05, 0.10 ± 0.01, 0.28 ± 0.06, and 0.48 ± 0.16 mg/kg. The mean time to reach maximum serum KRN23 levels was 7.0 to 8.5 days. The mean KRN23 half-life was 16.4 days. The mean area under the concentration–time curve (AUCn) for each dosing interval increased proportionally with increases in KRN23 dose. The mean intersubject variability in AUCn ranged from 30% to 37%. The area under the effect concentration–time curve (AUECn) for change from baseline in TmP per glomerular filtration rate, serum Pi, 1,25(OH)2D, and bone markers for each dosing interval increased linearly with increases in KRN23 AUCn. Linear correlation between serum KRN23 concentrations and increase in serum Pi support KRN23 dose adjustments based on predose serum Pi concentration
Osteoporosis-Related knowledge, self-efficacy and health beliefs among Chinese women with breast cancer
Vertebral fractures among breast cancer survivors in China: a cross-sectional study of prevalence and health services gaps
Abstract Background Breast cancer survivors are at high risk for fracture due to cancer treatment-induced bone loss, however, data is scarce regarding the scope of this problem from an epidemiologic and health services perspective among Chinese women with breast cancer. Methods We designed a cross-sectional study comparing prevalence of vertebral fractures among age- and BMI-matched women from two cohorts. Women in the Breast Cancer Survivors cohort were enrolled from a large cancer hospital in Beijing. Eligibility criteria included age 50–70 years, initiation of treatment for breast cancer at least 5 years prior to enrollment, and no history of metabolic bone disease or bone metastases. Data collected included sociodemographic characteristics; fracture-related risk factors, screening and preventive measures; breast cancer history; and thoracolumbar x-ray. The matched comparator group was selected from participants enrolled in the Peking Vertebral Fracture Study, an independent cohort of healthy community-dwelling postmenopausal women from Beijing. Results Two hundred breast cancer survivors were enrolled (mean age 57.5 ± 4.9 years), and compared with 200 matched healthy women. Twenty-two (11%) vertebral fractures were identified among breast cancer survivors compared with 7 (3.5%) vertebral fractures in the comparison group, yielding an adjusted odds ratio for vertebral fracture of 4.16 (95%CI 1.69–10.21, p < 0.01). The majority had early stage (85.3%) and estrogen and/or progesterone receptor positive (84.6%) breast cancer. Approximately half of breast cancer survivors reported taking calcium supplements, 6.1% reported taking vitamin D supplements, and only 27% reported having a bone density scan since being diagnosed with breast cancer. Conclusions Despite a four-fold increased odds of prevalent vertebral fracture among Chinese breast cancer survivors in our study, rates of screening for osteoporosis and fracture risk were low reflecting a lack of standardization of care regarding cancer-treatment induced bone loss
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