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1.
Kidney Int ; 105(1): 31-34, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38182299

RESUMEN

The Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for the Management of Glomerular Diseases was published in 2021. Since then, the pace of drug development for glomerular diseases has accelerated, due in large part to rapidly accumulating insights into disease pathogenesis from genetic and molecular studies of afflicted patients. To keep the Glomerular Diseases Guideline as current as possible, KDIGO made a commitment to the nephrology community to provide periodic updates, based on new developments for each disease. After the 2021 guideline was published, two novel drugs received regulatory approval for the management of lupus nephritis, leading to the first KDIGO guideline update. Herein, an executive summary of the most important guideline changes from the Lupus Nephritis chapter is provided as a quick reference.


Asunto(s)
Nefritis Lúpica , Nefrología , Humanos , Nefritis Lúpica/diagnóstico , Nefritis Lúpica/tratamiento farmacológico , Riñón , Desarrollo de Medicamentos
2.
Kidney Int ; 105(3): 447-449, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38388147

RESUMEN

In 2021, the Kidney Disease: Improving Global Outcomes (KDIGO) Guideline for the Management of Glomerular Diseases was published. KDIGO is committed to providing the nephrology community with periodic updates, based on new developments for each disease. For patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), avacopan received regulatory approval in late 2021, leading to this KDIGO guideline update. In addition, the evidence supporting a lower-dose glucocorticoid induction regimen or even complete replacement of glucocorticoids has become stronger. Herein, an executive summary of the most important guideline changes from the AAV chapter is provided as a quick reference.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Glomerulonefritis , Nefrología , Humanos , Glomerulonefritis/diagnóstico , Glomerulonefritis/tratamiento farmacológico , Riñón , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/diagnóstico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Anticuerpos Anticitoplasma de Neutrófilos , Glucocorticoides/uso terapéutico
3.
Phys Chem Chem Phys ; 25(16): 11707-11716, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37060119

RESUMEN

The emergence of self-organized behaviors such as spatio-temporal oscillations is well-known for complex reactions involving nonlinear chemical or thermal feedback. Recently, it was shown that local oscillations of the chemical species concentration can be induced under isothermal batch conditions for simple bimolecular A + B → C reactions, provided they are actively coupled with hydrodynamics. When two reactants A and B, initially separated in space, react upon diffusive contact, damped spatio-temporal oscillations could develop when the surface tension increases sufficiently in the reaction zone. Additionally, if the density decreases, the coupling of both surface tension- and buoyancy-driven contributions to the flow can further sustain this oscillatory instability. Here, we investigate the opposite case of a reaction inducing a localized decrease in surface tension and an increase in density in the reacting zones. In this case, the competition arising from the two antagonistic flows is needed to create oscillatory dynamics, i.e., no oscillations are observed for pure chemically driven Marangoni flows. We study numerically these scenarios in a 2-dimensional system and show how they are controlled by the following key parameters: (i) ΔM and ΔR governing the surface tension and density variation during the reaction, respectively, (ii) the layer thickness of the system, and (iii) its lateral length. This work is a further step toward inducing and controlling chemical oscillations in simple reactions.

4.
Kidney Int ; 102(5): 990-999, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36272755

RESUMEN

The Kidney Disease: Improving Global Outcomes (KDIGO) 2022 Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease (CKD) represents a focused update of the KDIGO 2020 guideline on the topic. The guideline targets a broad audience of clinicians treating people with diabetes and CKD. Topic areas for which recommendations are updated based on new evidence include Chapter 1: Comprehensive care in patients with diabetes and CKD and Chapter 4: Glucose-lowering therapies in patients with type 2 diabetes (T2D) and CKD. The content of previous chapters on Glycemic monitoring and targets in patients with diabetes and CKD (Chapter 2), Lifestyle interventions in patients with diabetes and CKD (Chapter 3), and Approaches to management of patients with diabetes and CKD (Chapter 5) has been deemed current and was not changed. This guideline update was developed according to an explicit process of evidence review and appraisal. Treatment approaches and guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence, and the strength of recommendations followed the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) approach. Limitations of the evidence are discussed, and areas for which additional research is needed are presented.


Asunto(s)
Diabetes Mellitus Tipo 2 , Insuficiencia Renal Crónica , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Glucosa
5.
Nature ; 534(7606): 200-5, 2016 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-27135931

RESUMEN

Modern humans arrived in Europe ~45,000 years ago, but little is known about their genetic composition before the start of farming ~8,500 years ago. Here we analyse genome-wide data from 51 Eurasians from ~45,000-7,000 years ago. Over this time, the proportion of Neanderthal DNA decreased from 3-6% to around 2%, consistent with natural selection against Neanderthal variants in modern humans. Whereas there is no evidence of the earliest modern humans in Europe contributing to the genetic composition of present-day Europeans, all individuals between ~37,000 and ~14,000 years ago descended from a single founder population which forms part of the ancestry of present-day Europeans. An ~35,000-year-old individual from northwest Europe represents an early branch of this founder population which was then displaced across a broad region, before reappearing in southwest Europe at the height of the last Ice Age ~19,000 years ago. During the major warming period after ~14,000 years ago, a genetic component related to present-day Near Easterners became widespread in Europe. These results document how population turnover and migration have been recurring themes of European prehistory.


Asunto(s)
Cubierta de Hielo , Población Blanca/genética , Población Blanca/historia , Animales , Evolución Biológica , ADN/análisis , ADN/genética , ADN/aislamiento & purificación , Europa (Continente) , Femenino , Efecto Fundador , Genética de Población , Historia Antigua , Migración Humana/historia , Humanos , Masculino , Medio Oriente , Hombre de Neandertal/genética , Filogenia , Dinámica Poblacional , Selección Genética , Análisis de Secuencia de ADN , Factores de Tiempo
6.
Kidney Int ; 100(4): 753-779, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34556300

RESUMEN

The Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for the Management of Glomerular Diseases is an update to the KDIGO 2012 guideline. The aim is to assist clinicians caring for individuals with glomerulonephritis (GN), both adults and children. The scope includes various glomerular diseases, including IgA nephropathy and IgA vasculitis, membranous nephropathy, nephrotic syndrome, minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), infection-related GN, antineutrophil cytoplasmic antibody (ANCA) vasculitis, lupus nephritis, and anti-glomerular basement membrane antibody GN. In addition, this guideline will be the first to address the subtype of complement-mediated diseases. Each chapter follows the same format providing guidance related to diagnosis, prognosis, treatment, and special situations. The goal of the guideline is to generate a useful resource for clinicians and patients by providing actionable recommendations based on evidence syntheses, with useful infographics incorporating views from experts in the field. Another aim is to propose research recommendations for areas where there are gaps in knowledge. The guideline targets a broad global audience of clinicians treating GN while being mindful of implications for policy and cost. Development of this guideline update followed an explicit process whereby treatment approaches and guideline recommendations are based on systematic reviews of relevant studies, and appraisal of the quality of the evidence and the strength of recommendations followed the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) approach. Limitations of the evidence are discussed, with areas of future research also presented.


Asunto(s)
Glomerulonefritis por IGA , Glomerulonefritis Membranosa , Glomerulonefritis , Nefrosis Lipoidea , Adulto , Niño , Glomerulonefritis/diagnóstico , Glomerulonefritis/terapia , Glomerulonefritis por IGA/diagnóstico , Glomerulonefritis por IGA/terapia , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/tratamiento farmacológico , Humanos , Riñón
7.
Phys Chem Chem Phys ; 23(32): 17606-17615, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34369507

RESUMEN

We study the impact of delayed feedbacks in the collective synchronization of ensembles of identical and autonomous micro-oscillators. To this aim, we consider linear arrays of Belousov-Zhabotinsky (BZ) oscillators confined in micro-compartmentalised systems, where the delayed feedback mimics natural lags that can arise due to the confinement properties and mechanisms driving the inter-oscillator communication. The micro-oscillator array is modeled as a set of Oregonator-like kinetics coupled via mass exchange of the chemical messengers. Changes in the synchronization patterns are explored by varying the delayed feedback introduced in the messenger species Br2. A direct transition from anti-phase to in-phase synchronization and back to the initial anti-phase scheme is observed by progressively increasing the time delay from zero to the value T0, which is the oscillation period characterising the system without any delayed coupling. The route from anti- to in-phase oscillations (and back) consists of regimes where windows of in-phase oscillations are periodically broken by anti-phase beats. Similarities between these phase transition dynamics and synchronization scenarios characterising the coordination of oscillatory limb movements are finally discussed.

8.
J Chem Phys ; 154(11): 114501, 2021 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-33752375

RESUMEN

Spatio-temporal oscillations can be induced under batch conditions with ubiquitous bimolecular reactions in the absence of any nonlinear chemical feedback, thanks to an active interplay between the chemical process and chemically driven hydrodynamic flows. When two reactants A and B, initially separated in space, react upon diffusive contact, they can power convective flows by inducing a localized variation of surface tension and density at the mixing interface. These flows feedback with the reaction-diffusion dynamics, bearing damped or sustained spatio-temporal oscillations of the concentrations and flow field. By means of numerical simulations, we detail the mechanism underlying these chemohydrodynamic oscillations and classify the main dynamical scenarios in the relevant space drawn by parameters ΔM and ΔR, which rule the surface tension- and buoyancy-driven contributions to convection, respectively. The reactor height is found to play a critical role in the control of the dynamics. The analysis reveals the intimate nature of these oscillatory phenomena and the hierarchy among the different phenomena at play: oscillations are essentially hydrodynamic and the chemical process features the localized trigger for Marangoni flows unstable toward oscillatory instabilities. The characteristic size of Marangoni convective rolls mainly determines the critical conditions and properties of the oscillations, which can be further tuned or suppressed by the buoyancy competition. We finally discuss the possible experimental implementation of such a class of chemo-hydrodynamic oscillator and its implications in fundamental and applied terms.

9.
Am J Phys Anthropol ; 176(1): 36-53, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34096038

RESUMEN

OBJECTIVES: By focusing on two Danish leprosaria (Naestved and Odense; 13th-16th c. CE) and using diet and origin as proxies, we follow a multi-isotopic approach to reconstruct life histories of patients and investigate how leprosy affected both institutionalized individuals and the medieval Danish community as a whole. MATERIALS AND METHODS: We combine archaeology, historical sources, biological anthropology, isotopic analyses (δ13 C, δ15 N, δ34 S, 87 Sr/86 Sr) and radiocarbon dating, and further analyze bones with different turnover rates (ribs and long bones). RESULTS: The δ13 C, δ15 N and δ34 S results indicate a C3 terrestrial diet with small contributions of marine protein for leprosy patients and individuals from other medieval Danish sites. A similar diet is seen through time, between males and females, and patients with and without changes on facial bones. The isotopic comparison between ribs and long bones reveals no significant dietary change. The δ34 S and 87 Sr/86 Sr results suggest that patients were local to the regions of the leprosaria. Moreover, the radiocarbon dates show a mere 50% agreement with the arm position dating method used in Denmark. CONCLUSIONS: A local origin for the leprosy patients is in line with historical evidence, unlike the small dietary contribution of marine protein. Although only 10% of the analyzed individuals have rib/long bone offsets that undoubtedly show a dietary shift, the data appear to reveal a pattern for 25 individuals (out of 50), with elevated δ13 C and/or δ15 N values in the ribs compared to the long bones, which points toward a communal type of diet and reveals organizational aspects of the institution.


Asunto(s)
Huesos/química , Isótopos/análisis , Lepra/etnología , Lepra/historia , Adulto , Antropología Física , Huesos/metabolismo , Dinamarca/etnología , Femenino , Historia Medieval , Humanos , Isótopos/metabolismo , Masculino , Datación Radiométrica
10.
J Oncol Pharm Pract ; 27(5): 1205-1213, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33736555

RESUMEN

INTRODUCTION: Our goal was to demonstrate the effects of occupational exposure to antineoplastic drugs on oxidative stress parameters and DNA damage in health professionals who manipulate and administer antineoplastic drugs in a University Hospital in Southern Brazil. METHODS: The case-control study with a longitudinal design, involved 64 individuals, 29 of them pharmacists, pharmacy technicians and nurses who were occupationally exposed to antineoplastic drugs and 35 professionals who were not exposed. Gene mutations were determined by micronucleus from salivary fluid; DNA damage by comet assay and oxidative stress parameters in whole blood were also evaluated. RESULTS: All workers exposed to antineoplastic drugs used personal protective equipment (PPE). It was demonstrated that the total nonprotein thiol and thiobarbituric acid reactive substances levels showed interaction between group and time, with higher levels one week after handling/administration of antineoplastic drugs in the exposed group (GEE, p ≤ 0.0001 and p = 0,013, respectively). Additionally, there was a group effect on the activities of the catalase and glutathione peroxidase antioxidant enzymes (GEE, p = 0.027 and p ≤ 0.0001, respectively), and workers occupationally exposed to antineoplastic drugs had higher enzyme activities compared to those not exposed. No genotoxic damage was demonstrated through the evaluated parameters. CONCLUSIONS: Despite the correct use of PPE, professionals occupationally exposed to antineoplastic drugs were more susceptible to oxidative stress than those not exposed. The evaluation of the studied parameters is especially important for the definition of conducts and practices in the area, always in search of guaranteeing the establishment of a rational policy to protect workers' health.


Asunto(s)
Antineoplásicos/efectos adversos , Personal de Salud , Exposición Profesional/efectos adversos , Estrés Oxidativo/efectos de los fármacos , Adulto , Estudios de Casos y Controles , Daño del ADN , Hospitales Universitarios , Humanos , Masculino , Equipo de Protección Personal
12.
Ann Intern Med ; 168(6): 422-430, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29459980

RESUMEN

Description: The Kidney Disease: Improving Global Outcomes (KDIGO) 2017 Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) is a selective update of the prior CKD-MBD guideline published in 2009. The guideline update and the original publication are intended to assist practitioners caring for adults with CKD and those receiving long-term dialysis. Methods: Development of the guideline update followed an explicit process of evidence review and appraisal. The approach adopted by the Work Group and the evidence review team was based on systematic reviews of relevant trials, appraisal of the quality of the evidence, and rating of the strength of recommendations according to the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Searches of the English-language literature were conducted through September 2015 and were supplemented with targeted searches through February 2017. Final modification of the guidelines was informed by a public review process involving numerous stakeholders, including patients, subject matter experts, and industry and national organizations. Recommendations: The update process resulted in the revision of 15 recommendations. This synopsis focuses primarily on recommendations for diagnosis of and testing for CKD-MBD and treatment of CKD-MBD that emphasizes decreasing phosphate levels, maintaining calcium levels, and addressing elevated parathyroid hormone levels in adults with CKD stage G3a to G5 and those receiving dialysis. Key elements include basing treatment on trends in laboratory values rather than a single abnormal result and being cautious to avoid hypercalcemia when treating secondary hyperparathyroidism.


Asunto(s)
Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/terapia , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/prevención & control , Humanos , Hipercalcemia/prevención & control , Hiperfosfatemia/sangre , Hiperfosfatemia/prevención & control , Hormona Paratiroidea/sangre , Diálisis Renal
13.
Kidney Int ; 93(6): 1281-1292, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29656903

RESUMEN

Patients with severely decreased glomerular filtration rate (GFR) (i.e., chronic kidney disease [CKD] G4+) are at increased risk for kidney failure, cardiovascular disease (CVD) events (including heart failure), and death. However, little is known about the variability of outcomes and optimal therapeutic strategies, including initiation of kidney replacement therapy (KRT). Kidney Disease: Improving Global Outcomes (KDIGO) organized a Controversies Conference with an international expert group in December 2016 to address this gap in knowledge. In collaboration with the CKD Prognosis Consortium (CKD-PC) a global meta-analysis of cohort studies (n = 264,515 individuals with CKD G4+) was conducted to better understand the timing of clinical outcomes in patients with CKD G4+ and risk factors for different outcomes. The results confirmed the prognostic value of traditional CVD risk factors in individuals with severely decreased GFR, although the risk estimates vary for kidney and CVD outcomes. A 2- and 4-year model of the probability and timing of kidney failure requiring KRT was also developed. The implications of these findings for patient management were discussed in the context of published evidence under 4 key themes: management of CKD G4+, diagnostic and therapeutic challenges of heart failure, shared decision-making, and optimization of clinical trials in CKD G4+ patients. Participants concluded that variable prognosis of patients with advanced CKD mandates individualized, risk-based management, factoring in competing risks and patient preferences.


Asunto(s)
Tasa de Filtración Glomerular , Riñón/fisiopatología , Nefrología/normas , Insuficiencia Renal Crónica/terapia , Toma de Decisiones Clínicas , Consenso , Medicina Basada en la Evidencia/normas , Humanos , Pronóstico , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/fisiopatología , Factores de Riesgo , Índice de Severidad de la Enfermedad
14.
Proc Natl Acad Sci U S A ; 112(18): 5607-12, 2015 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-25902508

RESUMEN

Paleoclimate records indicate a series of severe droughts was associated with societal collapse of the Classic Maya during the Terminal Classic period (∼800-950 C.E.). Evidence for drought largely derives from the drier, less populated northern Maya Lowlands but does not explain more pronounced and earlier societal disruption in the relatively humid southern Maya Lowlands. Here we apply hydrogen and carbon isotope compositions of plant wax lipids in two lake sediment cores to assess changes in water availability and land use in both the northern and southern Maya lowlands. We show that relatively more intense drying occurred in the southern lowlands than in the northern lowlands during the Terminal Classic period, consistent with earlier and more persistent societal decline in the south. Our results also indicate a period of substantial drying in the southern Maya Lowlands from ∼200 C.E. to 500 C.E., during the Terminal Preclassic and Early Classic periods. Plant wax carbon isotope records indicate a decline in C4 plants in both lake catchments during the Early Classic period, interpreted to reflect a shift from extensive agriculture to intensive, water-conservative maize cultivation that was motivated by a drying climate. Our results imply that agricultural adaptations developed in response to earlier droughts were initially successful, but failed under the more severe droughts of the Terminal Classic period.


Asunto(s)
Aclimatación , Agricultura/historia , Sequías/historia , Ecosistema , Agricultura/métodos , Agricultura/tendencias , Civilización/historia , Clima , Cambio Climático , Ambiente , Geografía , Sedimentos Geológicos/análisis , Sedimentos Geológicos/química , Historia Antigua , Humanos , Indígenas Sudamericanos/historia , Lípidos/análisis , México , Isótopos de Oxígeno , Plantas/química , Lluvia , Factores de Tiempo , Ceras/análisis
15.
Proc Natl Acad Sci U S A ; 112(25): 7683-8, 2015 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-26034284

RESUMEN

Modern human dispersal into Europe is thought to have occurred with the start of the Upper Paleolithic around 50,000-40,000 y ago. The Levantine corridor hypothesis suggests that modern humans from Africa spread into Europe via the Levant. Ksâr 'Akil (Lebanon), with its deeply stratified Initial (IUP) and Early (EUP) Upper Paleolithic sequence containing modern human remains, has played an important part in the debate. The latest chronology for the site, based on AMS radiocarbon dates of shell ornaments, suggests that the appearance of the Levantine IUP is later than the start of the first Upper Paleolithic in Europe, thus questioning the Levantine corridor hypothesis. Here we report a series of AMS radiocarbon dates on the marine gastropod Phorcus turbinatus associated with modern human remains and IUP and EUP stone tools from Ksâr 'Akil. Our results, supported by an evaluation of individual sample integrity, place the EUP layer containing the skeleton known as "Egbert" between 43,200 and 42,900 cal B.P. and the IUP-associated modern human maxilla known as "Ethelruda" before ∼ 45,900 cal B.P. This chronology is in line with those of other Levantine IUP and EUP sites and demonstrates that the presence of modern humans associated with Upper Paleolithic toolkits in the Levant predates all modern human fossils from Europe. The age of the IUP-associated Ethelruda fossil is significant for the spread of modern humans carrying the IUP into Europe and suggests a rapid initial colonization of Europe by our species.


Asunto(s)
Migración Humana , África , Aminoácidos/química , Teorema de Bayes , Radioisótopos de Carbono/análisis , Europa (Continente) , Historia Antigua , Humanos , Líbano , Isótopos de Oxígeno/análisis , Estereoisomerismo
16.
Kidney Int ; 92(1): 26-36, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28646995

RESUMEN

The KDIGO 2017 Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of CKD-MBD represents a selective update of the prior CKD-MBD Guideline published in 2009. This update, along with the 2009 publication, is intended to assist the practitioner caring for adults and children with chronic kidney disease (CKD), those on chronic dialysis therapy, or individuals with a kidney transplant. This review highlights key aspects of the 2017 CKD-MBD Guideline Update, with an emphasis on the rationale for the changes made to the original guideline document. Topic areas encompassing updated recommendations include diagnosis of bone abnormalities in CKD-mineral and bone disorder (MBD), treatment of CKD-MBD by targeting phosphate lowering and calcium maintenance, treatment of abnormalities in parathyroid hormone in CKD-MBD, treatment of bone abnormalities by antiresorptives and other osteoporosis therapies, and evaluation and treatment of kidney transplant bone disease.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Quelantes/uso terapéutico , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/tratamiento farmacológico , Suplementos Dietéticos , Medicina Basada en la Evidencia/normas , Nefrología/normas , Vitamina D/uso terapéutico , Biomarcadores/sangre , Calcio/sangre , Quelantes/efectos adversos , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/sangre , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico , Consenso , Suplementos Dietéticos/efectos adversos , Humanos , Hormona Paratiroidea/sangre , Fosfatos/sangre , Factores de Riesgo , Resultado del Tratamiento , Vitamina D/efectos adversos
17.
Phys Chem Chem Phys ; 19(48): 32235-32241, 2017 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-29188267

RESUMEN

In this paper we show that the active interplay of nonlinear kinetics and transport phenomena in a chemical oscillator can be exploited to induce and control chaos. To this aim we use as a model system the ferroin-catalysed Belousov-Zhabotinsky (BZ) oscillating reaction, which is known to evolve to characteristic chaotic transient dynamics when carried out under batch and unstirred conditions. In particular, chemical chaos was found to appear and disappear by following a Ruelle-Takens-Newhouse (RTN) scenario. Here we use medium viscosity as a bifurcation parameter to tune the reaction-diffusion-convection (RDC) interplay and force the reaction in a specific sequence of dynamical regimes: either (i) periodic → quasi-periodic → chaotic or (ii) periodic → quasi-periodic or (iii) only periodic. The medium viscosity can be set by adding different amounts of surfactant (sodium dodecyl sulphate), known to have a little impact on the reaction mechanism, above its critical micelle concentration. Experimental results are supported by means of numerical simulations of a RDC model, which combines self-sustained oscillations to the related chemically-induced buoyancy convection.

18.
Am J Respir Crit Care Med ; 192(4): 477-84, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25928547

RESUMEN

RATIONALE: Transmission is driving the global tuberculosis epidemic, especially in congregate settings. Worldwide, natural ventilation is the most common means of air disinfection, but it is inherently unreliable and of limited use in cold climates. Upper room germicidal ultraviolet (UV) air disinfection with air mixing has been shown to be highly effective, but improved evidence-based dosing guidelines are needed. OBJECTIVES: To test the efficacy of upper room germicidal air disinfection with air mixing to reduce tuberculosis transmission under real hospital conditions, and to define the application parameters responsible as a basis for proposed new dosing guidelines. METHODS: Over an exposure period of 7 months, 90 guinea pigs breathed only untreated exhaust ward air, and another 90 guinea pigs breathed only air from the same six-bed tuberculosis ward on alternate days when upper room germicidal air disinfection was turned on throughout the ward. MEASUREMENTS AND MAIN RESULTS: The tuberculin skin test conversion rates (>6 mm) of the two chambers were compared. The hazard ratio for guinea pigs in the control chamber converting their skin test to positive was 4.9 (95% confidence interval, 2.8-8.6), with an efficacy of approximately 80%. CONCLUSIONS: Upper room germicidal UV air disinfection with air mixing was highly effective in reducing tuberculosis transmission under hospital conditions. These data support using either a total fixture output (rather than electrical or UV lamp wattage) of 15-20 mW/m(3) total room volume, or an average whole-room UV irradiance (fluence rate) of 5-7 µW/cm(2), calculated by a lighting computer-assisted design program modified for UV use.


Asunto(s)
Desinfección , Control de Infecciones/métodos , Tuberculosis/prevención & control , Tuberculosis/transmisión , Rayos Ultravioleta , Ventilación , Animales , Cobayas , Prueba de Tuberculina
19.
Kidney Int ; 87(3): 502-28, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25651364

RESUMEN

A new definition and classification of chronic kidney disease-mineral and bone disorder (CKD-MBD) was proposed in 2005 and it was later followed by a guideline publication on this topic from Kidney Disease: Improving Global Outcomes (KDIGO) in 2009. This work recognized that CKD-MBD is a syndrome of bone abnormalities, laboratory abnormalities, and vascular calcification linked to fractures, cardiovascular disease, and mortality. Because of limited data at the time of the original guideline systematic review, many of the recommendations were cautiously vague. KDIGO convened a Controversies Conference in October 2013 to review the CKD-MBD literature published since the 2009 guideline. Specifically, the objective of this conference was to determine whether sufficient new data had emerged to support a reassessment of the CKD-MBD guideline and if so to determine the scope of these potential revisions. This report summarizes the results of these proceedings, highlighting important new studies conducted in the interval since the original KDIGO CKD-MBD guideline.


Asunto(s)
Enfermedades Óseas Metabólicas/complicaciones , Fracturas Óseas/prevención & control , Guías de Práctica Clínica como Asunto , Insuficiencia Renal Crónica/complicaciones , Calcificación Vascular/diagnóstico , Enfermedades Óseas Metabólicas/clasificación , Calcio/metabolismo , Quelantes del Calcio/uso terapéutico , Difosfonatos/uso terapéutico , Fracturas Óseas/etiología , Humanos , Hormona Paratiroidea/sangre , Fósforo/metabolismo , Insuficiencia Renal Crónica/clasificación , Calcificación Vascular/etiología , Vitamina D/uso terapéutico
20.
J Hum Evol ; 66: 89-94, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24331083

RESUMEN

In 1986-1987, three human remains were unearthed from macro-unit II of San Bernardino Cave (Berici Hills, Veneto, Italy), a deposit containing a late Mousterian lithic assemblage. The human remains (a distal phalanx, a lower right third molar and a lower right second deciduous incisor) do not show diagnostic morphological features that could be used to determine whether they were from Homo neanderthalensis or Homo sapiens. Despite being of small size, and thus more similar to recent H. sapiens, the specimens were attributed to Neandertals, primarily because they were found in Mousterian layers. We carried out a taxonomic reassessment of the lower right third molar (LRM3; San Bernardino 4) using digital morphometric analysis of the root, ancient DNA analysis, carbon and nitrogen isotope analyses, and direct accelerator mass spectrometry (AMS) radiocarbon dating of dentine collagen. Mitochondrial DNA analysis and root morphology show that the molar belongs to a modern human and not to a Neandertal. Carbon 14 ((14)C) dating of the molar attributes it to the end of the Middle Ages (1420-1480 cal AD, 2 sigma). Carbon and nitrogen isotope analyses suggest that the individual in question had a diet similar to that of Medieval Italians. These results show that the molar, as well as the other two human remains, belong to recent H. sapiens and were introduced in the Mousterian levels post-depositionally.


Asunto(s)
ADN Mitocondrial/genética , Diente Molar/anatomía & histología , Diente Molar/química , Hombre de Neandertal/clasificación , Raíz del Diente/anatomía & histología , Animales , Isótopos de Carbono/análisis , Cuevas , Cronología como Asunto , Fósiles , Humanos/clasificación , Italia , Espectrometría de Masas , Datos de Secuencia Molecular , Isótopos de Nitrógeno/análisis , Paleodontología , Filogenia , Datación Radiométrica , Análisis de Secuencia de ADN , Homología de Secuencia
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