258 research outputs found
Vitamin D. a dynamic molecule. how relevant might the dynamism for a vitamin be
Cholecalciferol, the precursor of Vitamin D3, is a very old, highly conserved, molecule. Its presence is evident in non-mineralized 750 million-year-old living species, such as plankton. The more active metabolites, a receptor and a D binding protein, appear later, along with the increasing complexity of animal species living in the sea. In the sea, however, the biological function of vitamin D is unlikely to be linked with mineral metabolism, and we can hypothesize a relationship with an immune response. It is in terrestrial animals exhibiting cellular bone that the complexity of vitamin D increases. At this stage of evolution, we see the appearance of bone cells that are capable of producing hormones that regulate and are regulated by vitamin D. This interaction starts a sophisticated metabolic system that modulates both mineral and energy metabolism for the requirements of the musculoskeletal system. Among the so-called pleiotropic effects of vitamin D, those resulting from the inhibitory effect on the renin-angiotensin system are of particular interest for nephrologists. Intriguingly, however, more than for anti-hypertensive effects, this interaction could be relevant for anti-inflammatory actions, possibly representative of a residual ancestral role of vitamin D. In addition, this evolutionary dynamism of the vitamin D system should not be separated from the chemical dynamism that characterizes the ligand molecule and its specific receptor. Both are capable of significant tridimensional modifications that contribute to an increase in the variability and the partial predictability of their final biological effect. A dynamic overview of this system that takes into account its evolutionary and adaptive aspects may be helpful to understand its biological complexity and to envisage why using vitamin D metabolites for therapeutic purposes is still a matter of debate
Cediranib for alveolar soft part sarcoma: a randomised study in relation to clinical practice.
Summary Background Alveolar soft-part sarcoma (ASPS) is a rare soft-tissue sarcoma that is unresponsive to chemotherapy. Cediranib, a tyrosine-kinase inhibitor, has shown substantial activity in ASPS in non-randomised studies. The Cediranib in Alveolar Soft Part Sarcoma (CASPS) study was designed to discriminate the effect of cediranib from the intrinsically indolent nature of ASPS. Methods In this double-blind, placebo-controlled, randomised, phase 2 trial, we recruited participants from 12 hospitals in the UK (n=7), Spain (n=3), and Australia (n=2). Patients were eligible if they were aged 16 years or older; metastatic ASPS that had progressed in the previous 6 months; had an ECOG performance status of 0–1; life expectancy of more than 12 weeks; and adequate bone marrow, hepatic, and renal function. Participants had to have no anti-cancer treatment within 4 weeks before trial entry, with exception of palliative radiotherapy. Participants were randomly assigned (2:1), with allocation by use of computer-generated random permuted blocks of six, to either cediranib (30 mg orally, once daily) or matching placebo tablets for 24 weeks. Treatment was supplied in number-coded bottles, masking participants and clinicians to assignment. Participants were unblinded at week 24 or sooner if they had progression defined by Response Evaluation Criteria in Solid Tumors (version 1.1); those on placebo crossed over to cediranib and all participants continued on treatment until progression or death. The primary endpoint was percentage change in sum of target marker lesion diameters between baseline and week 24 or progression if sooner, assessed in the evaluable population (all randomly assigned participants who had a scan at week 24 [or sooner if they progressed] with target marker lesions measured). Safety was assessed in all participants who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT01337401; the European Clinical Trials database, number EudraCT2010-021163-33; and the ISRCTN registry, number ISRCTN63733470 recruitment is complete and follow-up is ongoing. Findings Between July 15, 2011, and July 29, 2016, of 48 participants recruited, all were randomly assigned to cediranib (n=32) or placebo (n=16). 23 (48%) were female and the median age was 31 years (IQR 27–45). Median follow-up was 34·3 months (IQR 23·7–55·6) at the time of data cutoff for these analyses (April 11, 2018). Four participants in the cediranib group were not evaluable for the primary endpoint (one did not start treatment, and three did not have their scan at 24 weeks). Median percentage change in sum of target marker lesion diameters for the evaluable population was −8·3% (IQR −26·5 to 5·9) with cediranib versus 13·4% (IQR 1·1 to 21·3) with placebo (one-sided p=0·0010). The most common grade 3 adverse events on (blinded) cediranib were hypertension (six [19%] of 31) and diarrhoea (two [6%]). 15 serious adverse reactions in 12 patients were reported; 12 of these reactions occurred on open-label cediranib, and the most common symptoms were dehydration (n=2), vomiting (n=2), and proteinuria (n=2). One probable treatment-related death (intracranial haemorrhage) occurred 41 days after starting open-label cediranib in a patient who was assigned to placebo in the masked phase. Interpretation Given the high incidence of metastatic disease and poor long-term prognosis of ASPS, together with the lack of efficacy of conventional chemotherapy, our finding of significant clinical activity with cediranib in this disease is an important step towards the goal of long-term disease control for these young patients. Future clinical trials in ASPS are also likely to involve immune checkpoint inhibitors. Funding Cancer Research UK and AstraZeneca
A new technique for measuring fistula flow using venous blood gas oxygen saturation in patients with a central venous catheter
Background. Doppler ultrasound (DU) monitoring early after arteriovenous fistula (AVF) creation allows the identification of low blood flow (Qa) requiring prompt revision, but it is costly (needs skilled operators and technical instruments) and is not available in all dialysis units. Therefore alternative first-line methods to measure Qa would be welcomed.We reasoned that once an AVF is created, an increment in central venous oxygen saturation (ScvO2) is predictable and proportional to Qa.
Methods. Accordingly, in patients receiving dialysis through a central venous catheter (CVC) in whom an AVF was created, we measured, by means of blood gas analysis, the ScvO2 increment before and after manual compression of the arteriovenous shunt and verified its correlation with DU-measured Qa.
Results. We sampled blood gas in 18 patients with CVC and AVF before and after 30 s manual compression of the AVF. ScvO2 averaged 70.563% before and 65.263% after AVF closure, with an average drop of 5.163% (range 1–12). AVF Qa, which was measured within 24h by means of DU, averaged 6356349 mL/min (range 50–1300) and was strictly and positively correlated with DScvO2 (r ¼ 0.954, P<0.0001).
Conclusions. Therefore we suggest that in patients with CVC and a newly created AVF, it is possible to monitor AVF Qa without DU by simply measuring blood gas and DScvO2. This technique is simple, cheap, repeatable, non-invasive and operator independent and represents a new useful screening test to detect delayed AVF access maturation deserving prompt DU measurement and surgical revision. It helps to quickly identify patients in urgent need of DU verification and possible surgical revision. Regrettably, it is applicable only in patients with CVC
Oxygen Extraction Ratio (OER) as a Measurement of Hemodialysis (HD) Induced Tissue Hypoxia: A Pilot Study
HD tissue hypoxia associates with organ dysfunctions. OER, the ratio between SaO2and central-venous-oxygen-saturation, could estimate oxygen requirements during sessions, but no data are available. We evaluated OER behavior in 20 HD patients with permanent central venous catheter (CVC) as vascular access. Pre-HD OER (33.6 ± 1.4%; M ± SE) was higher than normal (range 20-30%). HD sessions increased OER to 39.2 ± 1.5% (M ± SE; p 40%. In HD patients with CVC as vascular access, OER is a cheap, easily measurable and repeatable parameter useful to assess intradialytic hypoxia, and a potential biomarker of HD related stress and morbidity, helpful to recognize patients at increased risk of mortality
Positioning novel biologicals in CKD-mineral and bone disorders
Renal osteodystrophy (ROD), the histologic bone lesions of chronic kidney disease (CKD), is now included in a wider syndrome with laboratory abnormalities of mineral metabolism and extra-skeletal calcifications or CKD-mineral and bone disorders (CKD-MBD), to highlight the increased burden of mortality. Aging people, frequently identified as early CKD, could suffer from either the classical age-related osteoporosis (OP) or ROD. Distinguishing between these two bone diseases may not be easy without bone biopsy. In any case, besides classical therapies for ROD, nephrologists are now challenged by the possibility of using new drugs developed for OP. Importantly, while therapies for ROD mostly aim at controlling parathyroid secretion with bone effects regarded as indirect, new drugs for OP directly modulate bone cells activity. Thus, their action could be useful in specific types of ROD. Parathyroid hormone therapy, which is anabolic in OP, could be useful in renal patients with low turnover bone disease. Denosumab, the monoclonal antibody against receptor activator of NF-κB ligand (RANK-L) that inhibits osteoclast activity and proliferation, could be beneficial in cases with high turnover bone. Use of romosozumab, the monoclonal antibody against sclerostin, which both stimulates osteoblasts and inhibits osteoclasts, could allow both anabolic and anti-resorptive effects. However, we should not forget the systemic role now attributed to CKD-MBD. In fact, therapies targeting bone cells activity could also result in unpredicted extra-bone effects and affect cardiovascular outcomes. In conclusion, the new biologicals established for OP could be useful in renal patients with either OP or ROD. In addition, their potential non-bone effects warrant investigation
Interactions of sclerostin with FGF23, soluble klotho and vitamin D in renal transplantation
Relationships of Sclerostin, a bone anti-anabolic protein, with biomarkers of mineral bone disorders in chronic kidney disease are still unsettled, in particular in kidney transplant (KTR). In 80 KTR patients (31F/49M, 54.7±10.3 years) we studied the relationships of serum Sclerostin with eGFR, Calcium, Phosphate, Alkaline Phosphatase (AP), intact Parathyroid hormone (iPTH), soluble alpha-Klotho (sKlotho), intact Fibroblast Growth Factor 23 (iFGF23), 25-hydroxyvitamin D(25D) and 1,25-dihydroxyvitamin D (1,25D). Thirty healthy subjects (35.0±12.4 years, eGFR 109.1±14.1 ml /min/1,73m2) served as control for Sclerostin, iFGF23 and sKlotho. With a median eGFR of 46.3 mL/min/1.73m2 (IQR, 36.2-58.3) our KTR had median Sclerostin levels of 23.7 pmol/L (IQR: 20.8-32.8), not different from controls (26.6 pmol/L, IQR: 22.0-32.2; p = n.s). Sclerostin correlated negatively with AP (r = -.251; p = 0.023) and positively with iFGF23 (r = .227; p = 0.017) and 25D (r = .214; p = 0.025). Age-adjusted multiple regression analysis identified AP and 1,25D as negative and 25D and sKlotho as positive best predictors of Sclerostin. No correlation was evident with eGFR. The negative correlation with AP confirms the direct anti-anabolic role of Sclerostin. The associations either negative or positive with iFGF23, sKlotho, and vitamin D metabolites suggest also a modulatory role in mineral homeostasis. In particular, the associations with iFGF23 (positive) and 1,25D (negative) underline the relevant inhibitory action of Sclerostin on vitamin D activation. In conclusion, Sclerostin levels in KTR are normal and influenced more by bone turnover than by eGFR. Its involvement with other hormones of mineral homeostasis (FGF23/Klotho and Vitamin D) is part of the sophisticated cross-talk between bone and the kidney
Long-term disease stability with bicalutamide in a man with aggressive angiomyxoma: case report and state of art
Aggressive angiomyxoma (AA) is a rare mesenchymal neoplasm, which is commonly diagnosed in females and located in the perineal and pelvic region. Tissue specimens of AA patients often show positivity for estrogen (ER) and progesterone receptors (PgR), while some cases of androgen receptor (AR) positivity have been reported in males. When feasible, surgical excision represent the most effective treatment of AA; however, when experiencing advanced or recurrent disease, local disease control could be achieved with systemic hormonal treatment. To date, evidence regarding AA management in male patients is scarce, and only a few cases have been reported in literature. Hereby, we describe the case of a 59-year-old-man suffering from perineal AA with positivity for androgen receptors (AR) showing a long-lasting disease stability during the treatment with an AR-blocking drug (bicalutamide). A literature review regarding the state of art of AA management with a particular look to male patients is also provided
Cytoreductive surgery alone or combined with hyperthermic intraperitoneal chemotherapy (HIPEC) for pseudomyxoma peritonei
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: The aim of this work is to evaluate the efficacy of cytoreductive surgery alone versus cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy (HIPEC), on patient benefits, complications and short-term outcomes in patients with pseudomyxoma peritonei (PMP). \ua9 2018 The Cochrane Collaboration
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