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1.
Front Microbiol ; 15: 1321059, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371938

RESUMO

Catalytic activity of microbial communities maintains the services and functions of soils. Microbial communities require energy and carbon for microbial growth, which they obtain by transforming organic matter (OM), oxidizing a fraction of it and transferring the electrons to various terminal acceptors. Quantifying the relations between matter and energy fluxes is possible when key parameters such as reaction enthalpy (∆rH), energy use efficiency (related to enthalpy) (EUE), carbon use efficiency (CUE), calorespirometric ratio (CR), carbon dioxide evolution rate (CER), and the apparent specific growth rate (µapp) are known. However, the determination of these parameters suffers from unsatisfying accuracy at the technical (sample size, instrument sensitivity), experimental (sample aeration) and data processing levels thus affecting the precise quantification of relationships between carbon and energy fluxes. To address these questions under controlled conditions, we analyzed microbial turnover processes in a model soil amended using a readily metabolizable substrate (glucose) and three commercial isothermal microcalorimeters (MC-Cal/100P, TAM Air and TAM III) with different sample sizes meaning varying volume-related thermal detection limits (LODv) (0.05-1mW L-1). We conducted aeration experiments (aerated and un-aerated calorimetric ampoules) to investigate the influence of oxygen limitation and thermal perturbation on the measurement signal. We monitored the CER by measuring the additional heat caused by CO2 absorption using a NaOH solution acting as a CO2 trap. The range of errors associated with the calorimetrically derived µapp, EUE, and CR was determined and compared with the requirements for quantifying CUE and the degree of anaerobicity (ηA). Calorimetrically derived µapp and EUE were independent of the instrument used. However, instruments with a low LODv yielded the most accurate results. Opening and closing the ampoules for oxygen and CO2 exchange did not significantly affect metabolic heats. However, regular opening during calorimetrically derived CER measurements caused significant measuring errors due to strong thermal perturbation of the measurement signal. Comparisons between experimentally determined CR, CUE,ηA, and modeling indicate that the evaluation of CR should be performed with caution.

2.
Nutrients ; 15(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37630700

RESUMO

More than any other mental illness, the course, prognosis, and therapy of anorexia nervosa are shaped by the physical changes associated with being underweight. This article provides an overview of the endocrine changes associated with malnutrition and underweight. This overview serves as a basis for understanding the other articles in this special issue, which deal with the health risks associated with being underweight. In this context, the differences between underweight in anorexia nervosa and in constitutional thinness are of particular importance in assessing the impact of intentional weight loss. In this context, the regulation of hunger and satiety deserves special interest, as this is the area in which the intentional influence on body weight comes into play. Clinical consequences on, for example, fertility, bone metabolism, the homeostasis of, for example, serum glucose levels, or body temperature have been observed for a long time; nonetheless, the medical responses, apart from vitamin supplementations and advice to gain weight, are still limited. Therefore, emphasis was placed on the potential improvement of outcomes through the administration of central or peripheral hormones. Studies were identified on PubMed via a selection of relevant keywords; original texts that were cited in reviews were studied where it was advantageous. This review found some promising data on bone health and the administration of transdermal oestrogen, which is not yet widely used, as well as distinct hormonal markers to differentiate between CT and AN. We concluded that the continuous efforts to investigate the role of endocrinology in underweight and/or anorexia nervosa lead to outcome benefits and that more and higher-powered studies are needed.


Assuntos
Anorexia Nervosa , Endocrinologia , Desnutrição , Humanos , Magreza , Temperatura Corporal
3.
Arch Public Health ; 80(1): 113, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395839

RESUMO

BACKGROUND: The COVID-19 outbreak has taken a heavy toll on the mental well-being of healthcare workers, even those who have not been directly involved in the care of acutely ill patients. The aims of this study were to identify the overall burden and mental health status of healthcare workers in pediatric developmental services under the influence of the COVID-19 pandemic, and to identify the risk and protective factors associated with mental health. METHODS: This cross-sectional web-based study was part of a large multicenter VOICE study conducted among employees ((neuro-)pediatricians, psychologists, speech therapists, occupational therapists, etc.) from various pediatric developmental services between June and July 2020. A total of 1291 questionnaires regarding overall burden, mental health status (depression, generalized anxiety disorder and emotional exhaustion) and risk and protective factors for mental health (working conditions, potential problems during the COVID-19 pandemic and psychological resources) were analyzed. Descriptive statistics and multiple linear regression were used for data analysis. RESULTS: A total of 44.5% (574/1291) participants felt a high or very high overall burden during the COVID-19 pandemic. Of all the participants, 14.6% (171/1173) reported clinically significant levels of depressive symptoms, 17.0% (199/1173) reported generalized anxiety disorder symptoms and 44.6% (532/1192) reported emotional exhaustion. Multiple linear regression analyses identified several common risk and protective factors for mental health status variables. The burden of an increase in the quantity of work, fear of work and fear of becoming infected showed the strongest negative associations, whereas psychological resources and sufficient relaxation in leisure time exhibited the strongest positive associations. CONCLUSION: Employees who were not directly involved in the care of acutely ill patients were also exposed to considerable stress, some of which was not different from that experienced by professionals who were directly affected. These employees should not be lost sight of and must be offered appropriate support.

4.
Artigo em Alemão | MEDLINE | ID: mdl-32494838

RESUMO

BACKGROUND: Children and adolescents with chronic diseases are a very heterogeneous group of patients with age-specific characteristics and a broad spectrum of underlying diseases. These patients require not only good medical care but also comprehensive support in order to achieve the greatest possible participation in social life. OBJECTIVE: In this review, the problems faced by children and adolescents with chronic diseases, as well as by their families, and the requirements for the best possible life management, are presented. The framework conditions of the healthcare system and the necessary supplementary social benefits are presented and necessary steps for further development are discussed. CONCLUSION: There are numerous services for children and adolescents with chronic diseases, as well as for their families. However due to the often-confusing access paths and a lack of coordination, these services are not seized to the extent necessary. Current efforts to improve coordination of social legislation and developing one-stop services represent a further step towards improving care.


Assuntos
Adaptação Psicológica , Doença Crônica , Atenção à Saúde , Adolescente , Criança , Alemanha , Humanos
5.
Artigo em Alemão | MEDLINE | ID: mdl-32504243

RESUMO

During the transition from adolescence to adulthood, people with disabilities have special problems and needs for adequate medical care and its integration into the overall environment. With the introduction of paragraphs 119c and 43b SGB V, the conditions for medical centers for people with disabilities (MZEB) were created and the special needs of this group of people recognized, while at the same time contributing to the implementation of Art. 25 of the United Nations Convention on the Rights of Persons with Disabilities. However, due to access restrictions, the MZEB can only provide adequate care for some of the people with disabilities. Regular conditions also need to be created so that the group of people with disabilities can receive adequate healthcare. The outcome of new care concepts should be confirmed by suitable studies.


Assuntos
Pessoas com Deficiência , Pediatria , Adolescente , Adulto , Criança , Atenção à Saúde , Alemanha , Humanos , Nações Unidas
6.
Microb Biotechnol ; 13(4): 1262-1272, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32212253

RESUMO

The detection and quantification of Legionella pneumophila (responsible for legionnaire's disease) in water samples can be achieved by various methods. However, the culture-based ISO 11731:2017, which is based on counts of colony-forming units per ml (CFU·ml-1 ) is still the gold standard for quantification of Legionella species (spp.). As a powerful alternative, we propose real-time monitoring of the growth of L. pneumophila using an isothermal microcalorimeter (IMC). Our results demonstrate that, depending on the initial concentration of L. pneumophila, detection times of 24-48 h can be reliably achieved. IMC may, therefore, be used as an early warning system for L. pneumophila contamination. By replacing only visual detection of growth by a thermal sensor, but otherwise maintaining the standardized protocol of the ISO 11731:2017, the new procedure could easily be incorporated into existing standards. The exact determination of the beginning of metabolic heat is often very difficult because at the beginning of the calorimetric signal the thermal stabilization and the metabolic heat development overlap. Here, we propose a new data evaluation based on the first derivation of the heat flow signal. The improved evaluation method can further reduce detection times and significantly increase the reliability of the IMC approach.


Assuntos
Legionella pneumophila , Legionella , Reprodutibilidade dos Testes , Microbiologia da Água
7.
Front Microbiol ; 10: 2530, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736935

RESUMO

Modern isothermal microcalorimeters (IMC) are able to detect the metabolic heat of bacteria with an accuracy sufficient to recognize even the smallest traces of bacterial contamination of water, food, and medical samples. The modern IMC techniques are often superior to conventional detection methods in terms of the detection time, reliability, labor, and technical effort. What is missing is a systematic analysis of the influence of the cultivation conditions on calorimetric detection. For the acceptance of IMC techniques, it is advantageous if already standardized cultivation techniques can be combined with calorimetry. Here we performed such a systematic analysis using Lactobacillus plantarum as a model bacterium. Independent of the cultivation techniques, IMC detections were much faster for high bacterial concentrations (>102 CFU⋅mL-1) than visual detections. At low bacterial concentrations (<102 CFU⋅mL-1), detection times were approximately the same. Our data demonstrate that all kinds of traditional cultivation techniques like growth on agar (GOA) or in agar (GIA), in liquid media (GL) or on agar after enrichment via membrane filtration (GF) can be combined with IMC. The order of the detection times was GF < GIA ≈ GL ≈ GOA. The observed linear relationship between the calorimetric detection times and the initial bacterial concentrations can be used to quantify the bacterial contamination. Further investigations regarding the correlation between the filling level (in mm) of the calorimetric vessel and the specific maximum heat flow (in µW⋅g-1) illustrated two completely different results for liquid and solid media. Due to the better availability of substrates and the homogeneous distribution of bacteria growing in a liquid medium, the volume-related maximum heat flow was independent on the filling level of the calorimetric vessels. However, in a solid medium, the volume-related maximum heat flow approached a threshold and achieved a maximum at low filling levels. This fundamentally different behavior can be explained by the spatial limitation of the growth of bacterial colonies and the reduced substrate supply due to diffusion.

8.
J Biol Chem ; 291(38): 19953-61, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27466364

RESUMO

The epsin N-terminal homology domain (ENTH) is a major player in clathrin-mediated endocytosis. To investigate the influence of initial membrane tension on ENTH binding and activity, we established a bilayer system based on adhered giant unilamellar vesicles (GUVs) to be able to control and adjust the membrane tension σ covering a broad regime. The shape of each individual adhered GUV as well as its adhesion area was monitored by spinning disc confocal laser microscopy. Control of σ in a range of 0.08-1.02 mN/m was achieved by altering the Mg(2+) concentration in solution, which changes the surface adhesion energy per unit area of the GUVs. Specific binding of ENTH to phosphatidylinositol 4,5-bisphosphate leads to a substantial increase in adhesion area of the sessile GUV. At low tension (<0.1 mN/m) binding of ENTH can induce tubular structures, whereas at higher membrane tension the ENTH interaction deflates the sessile GUV and thereby increases the adhesion area. The increase in adhesion area is mainly attributed to a decrease in the area compressibility modulus KA We propose that the insertion of the ENTH helix-0 into the membrane is largely responsible for the observed decrease in KA, which is supported by the observation that the mutant ENTH L6E shows a reduced increase in adhesion area. These results demonstrate that even in the absence of tubule formation, the area compressibility modulus and, as such, the bending rigidity of the membrane is considerably reduced upon ENTH binding. This renders membrane bending and tubule formation energetically less costly.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/química , Lipossomas Unilamelares/química , Humanos , Domínios Proteicos , Estrutura Secundária de Proteína , Tensão Superficial
10.
Int J Radiat Biol ; 90(7): 538-46, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24605769

RESUMO

PURPOSE: The time- and dose-dependent reconstitution of hematopoiesis after radiation exposure is strongly related to the stem cell population and can be used to predict hematological parameters. These parameters allow further insight into the hematopoietic system and might lead to the development of novel stem cell transplantation models. MATERIALS AND METHODS: CD4-/- C57Bl/6 mice, transgenic for human CD4 and HLA-DR3, were irradiated in a single (3, 6, 8 and 12 Gy) and fractionated (6 × 1 Gy, 6 × 1.5 Gy, 6 × 2 Gy; twice daily) dose regimen. Blood was analyzed weekly for red blood cells (RBC), hemoglobin concentration (Hb), hematocrit (HCT) and white blood cells (WBC). Organ and tissue damage after irradiation were examined by histopathology. RESULTS: The recovery curves for RBC, Hb, HCT and WBC showed the same velocity (< 1 week) for all radiation doses (3-12 Gy) starting at different, dose-dependent times. The only dose-dependent parameter was defined by the beginning of the recovery process (dose-dependent shift) and higher doses were related to a later recovery of the hematopoietic system. The RBC, Hb and HCT recovery was followed by a saturation curve reaching a final concentration independent of the radiation dose. Histological analysis of the bone marrow in the single dose cohort showed a dose-dependent reduction of the cellularity in the bone marrow cavities. The fractioned radiation dose cohort resulted in a regeneration of all bone marrow cavities. CONCLUSION: Specific functions were developed to describe the reconstitution of hematological parameters after total body irradiation.


Assuntos
Testes Hematológicos , Modelos Biológicos , Irradiação Corporal Total/efeitos adversos , Animais , Medula Óssea/efeitos da radiação , Relação Dose-Resposta à Radiação , Hemoglobinas/metabolismo , Humanos , Camundongos , Análise de Regressão
11.
Cell Mol Life Sci ; 71(11): 2135-48, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24067988

RESUMO

This is the first report showing that an epitope-specific ex vivo modulation of an allogeneic hematopoietic stem cell graft by the anti-human CD4 antibody MAX.16H5 IgG1 simultaneously facilitates the anti-tumor capacity of the graft (Graft-versus-leukemia effect, GvL) and the long-term suppression of the deleterious side effect Graft-versus-host-disease (GvHD). To distinguish and consolidate GvL from GvHD, the anti-human CD4 antibody MAX16.H5 IgG1 was tested in murine GvHD and tumor models. The survival rate was significantly increased in recipients receiving a MAX.16H5 IgG1 short-term (2 h) pre-incubated graft even when tumor cells were co-transplanted or when recipient mice were treated by MAX.16H5 IgG1 before transplantation. After engraftment, regulatory T-cells are generated only supporting the GvL effect. It was also possible to transfer the immune tolerance from GvHD-free recipient chimeras into third party recipient mice without the need of reapplication of MAX.16H5 IgG1 anti-human CD4 antibodies. These findings are also benefical for patients with leukemia when no matched related or unrelated donor is available and provides a safer allogeneic HSCT, which is more effective against leukemia. It also facilitates allogeneic (stem) cell transplantations for other indications (e.g., autoimmune-disorders).


Assuntos
Soro Antilinfocitário/farmacologia , Doença Enxerto-Hospedeiro/prevenção & controle , Efeito Enxerto vs Leucemia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Imunoglobulina G/farmacologia , Leucemia/terapia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Células Cultivadas , Modelos Animais de Doenças , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Tolerância Imunológica , Imunomodulação , Leucemia/imunologia , Leucemia/mortalidade , Leucemia/patologia , Camundongos , Camundongos Transgênicos , Análise de Sobrevida , Quimeras de Transplante/imunologia , Transplante Homólogo , Irradiação Corporal Total
12.
Methods Mol Biol ; 968: 93-104, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23296888

RESUMO

The polymerase chain reaction is a powerful molecular tool for the detection and analysis of very small amounts of DNA. Today, hybridization probes are often used in real-time PCR for more sensitive and specific detection of pathogens and for determination of gene regulation or mutation analysis instead of intercalating dyes like SYBR Green. Here, we describe how to generate suitable primers and hybridization probes for the specific detection of fungal DNA. Furthermore, we show the advantages of hybridization probes using the LightCycler-PCR for the detection of different Candida spp. and Aspergillus spp. in patient blood samples. The methods used to develop such PCR assays will also be presented in the following protocol.


Assuntos
Aspergillus/genética , Aspergillus/isolamento & purificação , Candida/genética , Candida/isolamento & purificação , Corantes Fluorescentes/química , Hibridização de Ácido Nucleico/métodos , Sondas de Oligonucleotídeos/genética , Primers do DNA/genética , Sondas de Oligonucleotídeos/química , RNA Fúngico/genética , RNA Ribossômico 18S/genética , Reação em Cadeia da Polimerase em Tempo Real , Especificidade da Espécie
13.
Cytometry A ; 81(6): 476-88, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22522779

RESUMO

Regulatory CD4(+) CD25(+) FoxP3(+) T cells (T(regs) ) suppress immunological reactions. However, the effect of adding T(regs) to hematopoietic stem cell grafts on recovery and graft versus host disease (GvHD) is unknown. T(regs) from splenocytes of C57Bl/6 and Balb/c wild-type mice were isolated by MACS separation and analyzed by flow cytometry. Using a murine syngeneic transplantation model that clearly distinguishes between donor and host hematopoiesis, we showed that co-transplantation of bone marrow cells (BMCs) with high levels of T(regs) leads to a 100% survival of the mice and accelerates the hematopoietic recovery significantly (full donor chimerism). In allogeneic transplantation, bone marrow and T(regs) co-transplantation were compared to allogeneic bone marrow transplantation with or without the addition of splenocytes. Survival, leukocyte recovery, chimerism at days -2, 19, 33, and 61 for murine CD4, human CD4, HLA-DR3, murine CD3, murine CD8, murine Balb/c-H2K(d) , murine C57Bl/6-H2K(b) , and GvHD appearance were analyzed. Allogeneic bone marrow transplantation requires the addition of splenocytes to reach engraftment. Mice receiving grafts with bone marrow, splenocytes and high levels of allogeneic T(regs) died within 28 days (hematopoietic failure). Here, we show also detailed flow cytometric data reagarding analysis of chimerism after transplantation in unique murine hematopoietic stem cell transplantation models. Our findings showed that the syngeneic co-transplantation of CD4(+) , CD25(+) , FoxP3(+) T-cells and BMCs induced a stimulating effect on reconstitution of hematopoiesis after irradiation. However, in the allogeneic setting the co-transplantation of T(regs) aggravates the engraftment of transplanted cells.


Assuntos
Transplante de Medula Óssea/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Linfócitos T Reguladores/transplante , Transplante Homólogo/efeitos adversos , Transplante Isogênico , Animais , Transplante de Medula Óssea/mortalidade , Quimerismo , Citometria de Fluxo , Doença Enxerto-Hospedeiro/imunologia , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Baço/imunologia , Taxa de Sobrevida , Linfócitos T Reguladores/imunologia , Falha de Tratamento , Irradiação Corporal Total
14.
Nat Commun ; 3: 612, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22215087

RESUMO

Electron transport in nanoscale structures is strongly influenced by the Coulomb interaction that gives rise to correlations in the stream of charges and leaves clear fingerprints in the fluctuations of the electrical current. A complete understanding of the underlying physical processes requires measurements of the electrical fluctuations on all time and frequency scales, but experiments have so far been restricted to fixed frequency ranges, as broadband detection of current fluctuations is an inherently difficult experimental procedure. Here we demonstrate that the electrical fluctuations in a single-electron transistor can be accurately measured on all relevant frequencies using a nearby quantum point contact for on-chip real-time detection of the current pulses in the single-electron device. We have directly measured the frequency-dependent current statistics and, hereby, fully characterized the fundamental tunnelling processes in the single-electron transistor. Our experiment paves the way for future investigations of interaction and coherence-induced correlation effects in quantum transport.

15.
Mycoses ; 55(5): 416-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22151280

RESUMO

An early diagnosis of an invasive fungal infection is essential for the initiation of a specific antifungal therapy and to avoid unnecessary discontinuation of a baseline therapy for haematological or oncological diseases. A real-time PCR assay for the detection and strain identification of Aspergillus species from culture strains was evaluated. DNA preparation was evaluated in contaminated culture media, urine and serum. A LightCycler PCR to differentiate various Aspergillus species was established. A real-time PCR assay for the detection of Aspergillus species was improved and was able to detect and differentiate medically important Aspergillus spp. The sensitivity of the test was <10 plasmid equivalents/assay. The real-time PCR assay is a useful tool for the rapid identification of Aspergillus species and might be useful as an early diagnostic tool to detect an invasive fungal infection. A real-time PCR protocol was improved by generating plasmid standards, additional generation of melting curves for species identification and the correlation between the melting temperature and the nucleotide exchanges within the used 18S rRNA gene region.


Assuntos
Aspergillus/classificação , Aspergillus/isolamento & purificação , Micologia/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Aspergillus/genética , Humanos , Plasma/microbiologia , Plasmídeos , Sensibilidade e Especificidade , Urina/microbiologia
16.
Cell Mol Life Sci ; 67(23): 4095-106, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20556631

RESUMO

Non-adherent bone marrow-derived cells (NA-BMCs) are a mixed cell population that can give rise to multiple mesenchymal phenotypes and that facilitates hematopoietic recovery. We characterized NA-BMCs by flow cytometry, fibroblast colony-forming units (CFU-f), real-time PCR, and in in vivo experiments. In comparison to adherent cells, NA-BMCs expressed high levels of CD11b(+) and CD90(+) within the CD45(+) cell fraction. CFU-f were significantly declining over the cultivation period, but NA-BMCs were still able to form CFU-f after 5 days. Gene expression analysis of allogeneic NA-BMCs compared to bone marrow (BM) indicates that NA-BMCs contain stromal, mesenchymal, endothelial cells and monocytes, but less osteoid, lymphoid, and erythroid cells, and hematopoietic stem cells. Histopathological data and analysis of weight showed an excellent recovery and organ repair of lethally irradiated mice after NA-BMC transplantation with a normal composition of the BM.


Assuntos
Células da Medula Óssea/fisiologia , Adesão Celular/fisiologia , Hematopoese/fisiologia , Animais , Biomarcadores/metabolismo , Células da Medula Óssea/citologia , Transplante de Medula Óssea , Antígenos CD4/genética , Antígenos CD4/metabolismo , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Quimeras de Transplante , Transplante Homólogo
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