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1.
Opt Express ; 31(12): 19703-19721, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381380

RESUMO

Methods of ablation imprints in solid targets are widely used to characterize focused X-ray laser beams due to a remarkable dynamic range and resolving power. A detailed description of intense beam profiles is especially important in high-energy-density physics aiming at nonlinear phenomena. Complex interaction experiments require an enormous number of imprints to be created under all desired conditions making the analysis demanding and requiring a huge amount of human work. Here, for the first time, we present ablation imprinting methods assisted by deep learning approaches. Employing a multi-layer convolutional neural network (U-Net) trained on thousands of manually annotated ablation imprints in poly(methyl methacrylate), we characterize a focused beam of beamline FL24/FLASH2 at the Free-electron laser in Hamburg. The performance of the neural network is subject to a thorough benchmark test and comparison with experienced human analysts. Methods presented in this Paper pave the way towards a virtual analyst automatically processing experimental data from start to end.

2.
Diabetes Obes Metab ; 18(8): 737-46, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27097592

RESUMO

Biosimilars are regulated differently from small-molecule generic, chemically derived medicines. The complexity of biological products means that small changes in manufacturing or formulation may result in changes in efficacy and safety of the final product. In the face of this complexity, the regulatory landscape for biosimilars continues to evolve, and global harmonization regarding requirements is currently lacking. It is essential that clinicians and patients are reassured that biosimilars are equally safe and effective as their reference product, and this is particularly important when interchangeability, defined as 'changing one medicine for another one which is expected to achieve the same clinical effect in a given clinical setting in any one patient', is considered. Although the automatic substitution (i.e. substitution without input from the prescribing healthcare provider) of biosimilars for reference products is currently not permitted by the majority of countries, this may change in the future. In order to demonstrate interchangeability between reference products and a biosimilar, more stringent and specific studies of the safety and efficacy of biosimilars are likely to be needed; however, guidance on the design of and the need for any such studies is currently limited. The present article provides an overview of the current regulatory framework around the demonstration of interchangeability with biosimilars, with a specific focus on biosimilar insulin analogues, and details experiences with other biosimilar products. In addition, designs for studies to evaluate interchangeability with a biosimilar insulin analogue product are proposed and a discussion about the implications of interchangeability in clinical practice is included.


Assuntos
Medicamentos Biossimilares , Substituição de Medicamentos , Controle de Medicamentos e Entorpecentes , Hipoglicemiantes , Insulina/análogos & derivados , Química Farmacêutica , Medicamentos Genéricos , Humanos
3.
J Mater Sci Mater Med ; 24(3): 573-81, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23239262

RESUMO

An extension of the application of calcium phosphate cements (CPC) to load-bearing defects, e.g. in vertebroplasty, would require less brittle cements with an increased fracture toughness. Here we report the modification of CPC made of alpha-tricalcium phosphate (α-TCP) with 2-hydroxyethylmethacrylate (HEMA), which is polymerised during setting to obtain a mechanically stable polymer-ceramic composite with interpenetrating organic and inorganic networks. The cement liquid was modified by the addition of 30-70 % HEMA and ammoniumpersulfate/tetramethylethylendiamine as initiator. Modification of α-TCP cement paste with HEMA decreased the setting time from 14 min to 3-8 min depending on the initiator concentration. The 4-point bending strength was increased from 9 MPa to more than 14 MPa when using 50 % HEMA, while the bending modulus decreased from 18 GPa to approx. 4 GPa. The addition of ≥50 % HEMA reduced the brittle fracture behaviour of the cements and resulted in an increase of the work of fracture by more than an order of magnitude. X-ray diffraction analyses revealed that the degree of transformation of α-TCP to calcium deficient hydroxyapatite was lower for polymer modified cements (82 % for polymer free cement and 55 % for 70 % HEMA) after 24 h setting, while the polymerisation of HEMA in the cement liquid was quantitative according to FT-IR spectroscopy. This work demonstrated the feasibility of producing fracture resistant dual-setting calcium phosphate cements by adding water soluble polymerisable monomers to the liquid cement phase, which may be suitable for an application in load-bearing bone defects.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Nat Commun ; 13(1): 198, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017539

RESUMO

The conversion of photon energy into other energetic forms in molecules is accompanied by charge moving on ultrafast timescales. We directly observe the charge motion at a specific site in an electronically excited molecule using time-resolved x-ray photoelectron spectroscopy (TR-XPS). We extend the concept of static chemical shift from conventional XPS by the excited-state chemical shift (ESCS), which is connected to the charge in the framework of a potential model. This allows us to invert TR-XPS spectra to the dynamic charge at a specific atom. We demonstrate the power of TR-XPS by using sulphur 2p-core-electron-emission probing to study the UV-excited dynamics of 2-thiouracil. The method allows us to discover that a major part of the population relaxes to the molecular ground state within 220-250 fs. In addition, a 250-fs oscillation, visible in the kinetic energy of the TR-XPS, reveals a coherent exchange of population among electronic states.

5.
Trends Ecol Evol ; 37(4): 309-321, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34955328

RESUMO

Wild bee populations are declining due to human activities, such as land use change, which strongly affect the composition and diversity of available plants and food sources. The chemical composition of food (i.e., nutrition) in turn determines the health, resilience, and fitness of bees. For pollinators, however, the term 'health' is recent and is subject to debate, as is the interaction between nutrition and wild bee health. We define bee health as a multidimensional concept in a novel integrative framework linking bee biological traits (physiology, stoichiometry, and disease) and environmental factors (floral diversity and nutritional landscapes). Linking information on tolerated nutritional niches and health in different bee species will allow us to better predict their distribution and responses to environmental change, and thus support wild pollinator conservation.


Assuntos
Biodiversidade , Polinização , Animais , Abelhas , Ecossistema , Flores/fisiologia , Fenótipo , Plantas , Polinização/fisiologia
6.
Plant Dis ; 95(8): 945-950, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30732111

RESUMO

Soybean dwarf virus (SbDV) exists as several distinct strains based on symptomatology, vector specificity, and host range. Originally characterized Japanese isolates of SbDV were specifically transmitted by Aulacorthum solani. More recently, additional Japanese isolates and endemic U.S. isolates have been shown to be transmitted by several different aphid species. The soybean aphid, Aphis glycines, the only aphid that colonizes soybean, has been shown to be a very inefficient vector of some SbDV isolates from Japan and the United States. Transmission experiments have shown that the soybean aphid can transmit certain isolates of SbDV from soybean to soybean and clover species and from clover to clover and soybean with long acquisition and inoculation access periods. Although transmission of SbDV by the soybean aphid is very inefficient, the large soybean aphid populations that develop on soybean may have epidemiological potential to produce serious SbDV-induced yield losses.

7.
Plant Dis ; 94(5): 528-533, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-30754478

RESUMO

Huanglongbing (HLB), considered to be the most serious insect-vectored bacterial disease of citrus, is transmitted in nature by the Asian citrus psyllid Diaphorina citri and the African citrus psyllid Trioza erytreae. D. citri was discovered in southern Florida in 1998 and the HLB disease in 2005. Both have become established throughout citrus-producing areas of Florida. Murraya species are widely grown in southern Florida as ornamental hedges and are readily colonized by D. citri vectors. Colonies of D. citri, isolates of 'Candidatus Liberibacter asiaticus' from Taiwan and Florida, and the Murraya species were established in the BSL-3 biosecurity facility at Fort Detrick. In controlled inoculation experiments, D. citri transmitted 'Ca. L. asiaticus' into M. paniculata (34/36 plants) and M. exotica (22/23 plants), but not into Bergera (Murraya) koenigii. Disease symptoms rarely developed in Murraya plants; however, positive infections were determined by conventional and real-time polymerase chain reaction (PCR). Back-inoculations of 'Ca. L. asiaticus' from M. paniculata to Madam Vinous sweet orange resulted in disease development in 25% of the inoculated plants. Considerable variability was observed in infection rates, titer, and persistence of 'Ca. L. asiaticus' in infected Murraya.

8.
Blood Purif ; 27(4): 330-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19270452

RESUMO

This study used multi-frequency bioimpedance spectroscopy (BIS) of the arm and whole body to estimate muscle mass (MM) and subcutaneous adipose tissue (SAT) in 31 hemodialysis (HD) patients comparing these results with magnetic resonance imaging (MRI) and body potassium ((40)K) as gold standards. Total body and arm MM (MM(MRI)) and SAT (SAT(MRI)) were measured by MRI. All measurements were made before dialysis treatment. Regression models with the arm (aBIS) and whole body (wBIS) resistances were established. Correlations between gold standards and the BIS model were high for the arm SAT (r(2) = 0.93, standard error of estimate (SEE) = 3.6 kg), and whole body SAT (r(2) = 0.92, SEE = 3.5 kg), and for arm MM (r(2) = 0.84, SEE = 2.28 kg) and whole body MM (r(2) = 0.86, SEE = 2.28 kg). Total body MM and SAT can be accurately predicted by arm BIS models with advantages of convenience and portability, and it should be useful to assess nutritional status in HD patients.


Assuntos
Tecido Adiposo , Composição Corporal , Impedância Elétrica , Músculos , Diálise Renal , Negro ou Afro-Americano , Braço , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estado Nutricional , Potássio/análise , Padrões de Referência , Reprodutibilidade dos Testes
9.
J Phys Condens Matter ; 21(26): 264012, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21828460

RESUMO

A one-dimensional silver (Ag) nanoparticle gradient layer is prepared from an aqueous colloidal solution upon a polystyrene (PS) coated silicon (Si) substrate. For preparation two walls of different wettability are used. The 40 nm PS-layer exhibits a locally constant film thickness due to the strong roughness correlation with the underlying Si-substrate and is less wettable as compared to the glass plate placed above. The Ag nanoparticles have a triangular prism-like shape. The structural characterization of the obtained complex gradient formed by drying is performed with microbeam grazing incidence small-angle x-ray scattering based on compound refractive lenses. Due to the adsorption from aqueous solution in the selective geometry a double gradient type structure defined by two areas with characteristic lateral lengths and a cross-over regime between both is observed.

10.
Bull Entomol Res ; 99(4): 337-46, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19063760

RESUMO

There is a severe shortage of knowledge of bee biogeography. Some former studies have highlighted a link between bee diversity and xeric ecosystems, but we know practically nothing of the macro-ecological factors driving bee diversity. The present study aims to analyse the main macro-ecological factors driving bee species-richness in the Saharan region. Our dataset includes 25,000+ records for localities in Africa, between 37 degrees and 10 degrees N. Maps and GIS were used to get a first overview of the distribution of the studied taxa. Partial least squares analysis (PLS) was used to study the impact of a set of ecological factors on the bee species richness (SR). The mapping highlighted the clustering of the highest bee SR values in some parts of the Saharan area (e.g. Maghreb, western Africa). In Central Sahara, there is an obvious topological coincidence of the high SR, the local mountain chains and the inland waters. The PLS helped to quantify the relationships between bee SR and a set of eco-climatic variables. It also highlighted a residual variance not explained by the considered descriptors. Our results recover the tight link between bee SR and xeric ecosystems. They also suggest that, within these ecosystems, bee SR is driven by an optimum of the energy-water balance (on which adjustment is allowed by the above gradients).


Assuntos
Abelhas/fisiologia , Biodiversidade , Demografia , África do Norte , Animais , Água Doce , Sistemas de Informação Geográfica , Geografia , Análise Multivariada
11.
J Wound Care ; 18(3): 123-28, 131, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19247233

RESUMO

OBJECTIVE: To establish a new wound model that can induce uniform abrasions and use it to assess the healing properties of a range of products commonly applied to these wounds. METHOD: Ten healthy volunteers were enrolled into an open-label, randomised, intra-individual comparison pilot study. Five standardised, superficial abrasions were induced on their forearms by repeatedly scrubbing the skin with a surgical brush until the first signs of uniform glistening and punctuate bleeding were observed. Three products that promote a moist wound environment (polyurethane, hydrocolloid, hydrogel) and two standard plasters were randomly allocated to the test areas. RESULTS: Evaluation of wound healing on days 2, 5, 8 and 14 +/- 1 showed best results for the polyurethane and hydrocolloid plasters. Visible re-epithelialisation was recorded on days 5 and 8. More than 50% of the wound area had closed. Video microscope images support these findings. The investigator and volunteers assessed cosmetic outcomes on day 31 +/- 2. Best results were obtained for the polyurethane and hydrocolloid products, which had high mean scores close to the maximum of 10. Histological examination of biopsies taken from the abrasions of two volunteers showed the dermis remained intact, making the model highly suitable for the study of superficial wounds. CONCLUSION: Uniform and identical standardised wounds created using an abrasive brush technique can be used to reliably detect differences in the performance of plasters intended for superficial wounds. In general, products that promote a moist wound environment produced better results than those that promote a dry wound environment, with an earlier onset of healing and better healing outcomes. Superficial cutaneous wounds treated with polyurethane or hydrocolloid products demonstrated superior rates of re-epithelialisation and overall cosmetic outcomes. DECLARATION OF INTEREST: This study was funded by Beiersdorf AG. Neither author has any interest in the sponsor's commercial activities.


Assuntos
Curativos Hidrocoloides , Modelos Biológicos , Curativos Oclusivos , Cicatrização , Ferimentos e Lesões/terapia , Adulto , Feminino , Humanos , Masculino , Projetos Piloto , Poliuretanos , Padrões de Referência , Projetos de Pesquisa , Ferimentos e Lesões/patologia
12.
J Wound Care ; 18(5): 208, 210-4, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19440173

RESUMO

OBJECTIVE: To compare the efficacy and safety of a polyurethane dressing with a silicone sheet in the treatment of hypertrophic scars. METHOD: Sixty patients participated in this intra-individual 12-week clinical trial. Each scar was divided into two areas, to which the polyurethane dressing and the silicone sheet were randomly allocated. The primary outcome measure was the percentage change in the overall scar index (SI) between baseline and week 12. Secondary outcome measures included changes in skin redness, objectively measured by chromametry, and patients views on the aesthetic outcome of treatment. RESULTS: Both therapies achieved favourable results for all of the above outcome measures. Results were comparable for the primary outcome measure: 29.4% versus 33.7% for the silicone sheet and polyurethane product respectively. The decrease in the overall SI was significantly more pronounced for the polyurethane product after week 4 (5.6% versus 15.8% for the silicone sheet; p<0.0001) and week 8 (20.2% versus 27.1%; p=0.012). CONCLUSION: Both regimens were associated with a significant reduction in the clinical signs of hypertrophic scars over 12 weeks of treatment. The polyurethane dressing demonstrated a significantly more pronounced reduction in severity of these clinical signs after four and eight weeks of treatment and was better tolerated than the silicone sheet. l DECLARATION OF INTEREST: This study was funded by Beiersdorf AG. proDERM is an independent research company, and none of the authors have an interest in the sponsors commercial activities.


Assuntos
Bandagens/normas , Cicatriz Hipertrófica/terapia , Poliuretanos/normas , Silicones/normas , Adolescente , Adulto , Cicatriz Hipertrófica/patologia , Estética , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Fotometria , Índice de Gravidade de Doença , Método Simples-Cego , Higiene da Pele/métodos , Estatísticas não Paramétricas , Resultado do Tratamento , Cicatrização
13.
Physiol Meas ; 29(6): S503-16, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18544816

RESUMO

Although many methods have been utilized to measure degrees of body hydration, and in particular to estimate normal hydration states (dry weight, DW) in hemodialysis (HD) patients, no accurate methods are currently available for clinical use. Biochemcial measurements are not sufficiently precise and vena cava diameter estimation is impractical. Several bioimpedance methods have been suggested to provide information to estimate clinical hydration and nutritional status, such as phase angle measurement and ratio of body fluid compartment volumes to body weight. In this study, we present a calf bioimpedance spectroscopy (cBIS) technique to monitor calf resistance and resistivity continuously during HD. Attainment of DW is defined by two criteria: (1) the primary criterion is flattening of the change in the resistance curve during dialysis so that at DW little further change is observed and (2) normalized resistivity is in the range of observation of healthy subjects. Twenty maintenance HD patients (12 M/8 F) were studied on 220 occasions. After three baseline (BL) measurements, with patients at their DW prescribed on clinical grounds (DW(Clin)), the target post-dialysis weight was gradually decreased in the course of several treatments until the two dry weight criteria outlined above were met (DW(cBIS)). Post-dialysis weight was reduced from 78.3 +/- 28 to 77.1 +/- 27 kg (p < 0.01), normalized resistivity increased from 17.9 +/- 3 to 19.1 +/- 2.3 x 10(-2) Omega m(3) kg(-1) (p < 0.01). The average coefficient of variation (CV) in three repeat measurements of DW(cBIS) was 0.3 +/- 0.2%. The results indicate that cBIS utilizing a dynamic technique continuously during dialysis is an accurate and precise approach to specific end points for the estimation of body hydration status. Since no current techniques have been developed to detect DW as precisely, it is suggested as a standard to be evaluated clinically.


Assuntos
Líquidos Corporais/fisiologia , Eletrofisiologia/métodos , Perna (Membro)/fisiologia , Diálise Renal , Algoritmos , Impedância Elétrica , Eletrodos , Feminino , Humanos , Masculino , Análise Espectral
14.
Int J Artif Organs ; 30(11): 1008-13, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18067103

RESUMO

Despite advances in dialysis technology and an increasing variety of effective phosphate binders (PB) target phosphate levels are achieved in only a minority of ESRD patients. This is only partly explained by insufficient weekly phosphate elimination (2400 - 3000 mg) with traditional 3x 4-5 h dialysis, which is significantly lower than the total amount of phosphorus (iP) accrued from dietary consumption during the same period (about 5000 g). In addition, meal-to-meal and day-to-day variability of dietary iP intake in conjunction with inadequate phosphate binder dosing in relation to meal iP content also may contribute to hyperphosphatemia. It was hypothesized that self-adjusting of PB dose to meal iP content by the patient himself will improve management of hyperphosphatemia. A specific Phosphate-Education-Program (PEP) was developed to train patients to eye-estimate meal iP content by "Phosphate Units" (PU), which categorize food components according to iP content (100 mg iP per serving size = 1 PU). To allow self-adjustment of PB dose to meal iP content, a new prescription concept for PB was required. Phosphate binders are no longer prescribed using a fixed dosing regimen but only in strict relation to meal iP content (#PB per PU). In close collaboration with the patient the PB/PU ratio is then adapted to individual patient needs until serum phosphate targets are met. This new management concept for hyperphosphatemia is the first to establish a direct link between dietary phosphorus intake and PB dose and to empower patients to self-adjust PB dose according to dietary phosphorus intake. Clinical studies are under way to establish the practical value of this new concept for CKD and ESRD patients.


Assuntos
Doenças Cardiovasculares/mortalidade , Hiperfosfatemia/prevenção & controle , Falência Renal Crônica/complicações , Educação de Pacientes como Assunto , Fosfatos/administração & dosagem , Doenças Cardiovasculares/etiologia , Dieta , Humanos , Hiperfosfatemia/etiologia
15.
Vasa ; 36(4): 253-60, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18357917

RESUMO

In recent years the importance of circulating bone marrow-derived cells in angiogenesis and collateral growth has been demonstrated in peripheral artery disease (PAD) and other ischaemic diseases. Although the mechanisms by which these cells exert their angiogenetic/arteriogenetic effects are not completely understood, improving the accumulation of bone marrow-derived cells at the site of vascular growth using cytokines has become one aim in some of the regenerative therapies. Interestingly recent data indicate that in addition to effects attributed to such accumulated cells there are also direct effects of cytokines used via their receptors. Several investigations in animal hind limb models of ischaemia have demonstrated the beneficial effect of bone marrow mobilisation using colony-stimulating factors (CSF) on collateral growth and perfusion recovery. Clinical studies in PAD patients, however are still rare and led to inconsistent data, in part due to different application protocols, choice of cytokine and low patient numbers with strong placebo effects. Moreover; the aetiology of the disease in humans differs markedly from the artificial occlusion of the femoral artery in a mostly healthy animal in the preclinical setting. Another approach to enhance arteriogenesis, which has been successful in animal models of hind limb ischaemia, is the local injection of the monocyte chemoattractant protein 1 (MCP-1). This treatment stimulated the invasion of monocytes leading to improved collateral growth and restoration of limb perfusion. Recent reports from animal experiments, in which both treatment strategies were combined (i.e. bone marrow mobilisation and enhancement of cell migration to the site of vascular growth), have shown strong synergistic effects, pointing at the importance to orchestrate the different processes involved in vascular repair in order to achieve maximal therapeutic effects.


Assuntos
Arteriopatias Oclusivas/terapia , Células da Medula Óssea , Citocinas/uso terapêutico , Isquemia/terapia , Perna (Membro)/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Arteriopatias Oclusivas/fisiopatologia , Células da Medula Óssea/efeitos dos fármacos , Quimiocina CCL2 , Modelos Animais de Doenças , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Membro Posterior/irrigação sanguínea , Humanos , Isquemia/fisiopatologia
16.
Int Urol Nephrol ; 39(1): 261-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17333516

RESUMO

Biopharmaceuticals are recombinant protein drugs which are produced by biotechnology. The availability of such molecules has revolutionised the way we treat many diseases. However, the patents for many originator biopharmaceuticals are expiring, and a new generation of follow-on molecules, termed "biosimilars", are under development. Health care providers perceive biosimilars to be cheap replacements for originator drugs such as recombinant human erythropoietin and human growth hormone. However, concerns have been raised about the comparability of biosimilars with originator products especially in light of the complex manufacturing process required to produce biopharmaceuticals. The complexity of protein molecules renders it impossible to produce identical copies; this in turn raises questions on the safety of follow-on biosimilar products, particularly with respect to immunogenicity. This review briefly outlines the process of biopharmaceutical production, potential problems that can arise from their long-term use in patients, and the issues facing regulatory bodies as they look to institute guidelines for new biosimilar molecules.


Assuntos
Produtos Biológicos , Biotecnologia/tendências , Medicamentos Genéricos , Proteínas Recombinantes , Produtos Biológicos/biossíntese , Produtos Biológicos/imunologia , Biotecnologia/legislação & jurisprudência , Humanos , Legislação de Medicamentos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia
18.
J Appl Physiol (1985) ; 100(2): 717-24, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16254072

RESUMO

Discrepancies in body fluid estimates between segmental bioimpedance spectroscopy (SBIS) and gold-standard methods may be due to the use of a uniform value of tissue resistivity to compute extracellular fluid volume (ECV) and intracellular fluid volume (ICV). Discrepancies may also arise from the exclusion of fluid volumes of hands, feet, neck, and head from measurements due to electrode positions. The aim of this study was to define the specific resistivity of various body segments and to use those values for computation of ECV and ICV along with a correction for unmeasured fluid volumes. Twenty-nine maintenance hemodialysis patients (16 men) underwent body composition analysis including whole body MRI, whole body potassium (40K) content, deuterium, and sodium bromide dilution, and segmental and wrist-to-ankle bioimpedance spectroscopy, all performed on the same day before a hemodialysis. Segment-specific resistivity was determined from segmental fat-free mass (FFM; by MRI), hydration status of FFM (by deuterium and sodium bromide), tissue resistance (by SBIS), and segment length. Segmental FFM was higher and extracellular hydration of FFM was lower in men compared with women. Segment-specific resistivity values for arm, trunk, and leg all differed from the uniform resistivity used in traditional SBIS algorithms. Estimates for whole body ECV, ICV, and total body water from SBIS using segmental instead of uniform resistivity values and after adjustment for unmeasured fluid volumes of the body did not differ significantly from gold-standard measures. The uniform tissue resistivity values used in traditional SBIS algorithms result in underestimation of ECV, ICV, and total body water. Use of segmental resistivity values combined with adjustment for body volumes that are neglected by traditional SBIS technique significantly improves estimations of body fluid volume in hemodialysis patients.


Assuntos
Compartimentos de Líquidos Corporais , Impedância Elétrica , Diálise Renal , Análise Espectral/métodos , Algoritmos , Composição Corporal , Água Corporal , Líquido Extracelular , Feminino , Humanos , Líquido Intracelular , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Técnica de Diluição de Radioisótopos , Reprodutibilidade dos Testes
19.
Clin Nutr ; 25(2): 295-310, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16697495

RESUMO

Enteral nutrition (EN) by means of oral nutritional supplements (ONS) and tube feeding (TF) offers the possibility of increasing or ensuring nutrient intake in cases where normal food intake is inadequate. These guidelines are intended to give evidence-based recommendations for the use of ONS and TF in nephrology patients. They were developed by an interdisciplinary expert group in accordance with officially accepted standards and are based on all relevant publications since 1985. They were discussed and accepted in a consensus conference. Because of the nutritional impact of renal diseases, EN is widely used in nephrology practice. Patients with acute renal failure (ARF) and critical illness are characterized by a highly catabolic state and need depurative techniques inducing massive nutrient loss. EN by TF is the preferred route for nutritional support in these patients. EN by means of ONS is the preferred way of refeeding for depleted conservatively treated chronic renal failure patients and dialysis patients. Undernutrition is an independent factor of survival in dialysis patients. ONS was shown to improve nutritional status in this setting. An increase in survival has been recently reported when nutritional status was improved by ONS.


Assuntos
Nutrição Enteral/normas , Gastroenterologia/normas , Padrões de Prática Médica/normas , Insuficiência Renal/terapia , Europa (Continente) , Humanos
20.
Case Rep Crit Care ; 2016: 4893496, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27867668

RESUMO

Purpose. Pulmonary-renal syndrome (PRS) is characterized by diffuse alveolar hemorrhage and rapidly progressive glomerulonephritis mainly due to autoimmune etiologies. Seronegative PRS is a challenging entity to the clinician, since early diagnosis may be missed leading to delayed appropriate treatment. Materials and Methods. We present the clinical course of a 77-year-old patient who was admitted under the suspected diagnosis of pneumogenic sepsis and septic renal failure with fever, dyspnea, and elevated CRP levels. The diagnosis of pulmonary-renal syndrome was initially missed because of the absence of autoantibodies in all serological findings. Results. Despite delayed initiation of immunosuppressive therapy and a prolonged period of dialysis and extracorporeal membrane oxygenation the patient recovered well and was released to a rehabilitation center with nearly normalized creatinine levels. The diagnosis of PRS was established by renal biopsy. Conclusion. This case illustrates the important differential diagnosis of seronegative pulmonary-renal syndrome in patients with pulmonary and renal impairment.

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