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1.
Hepatology ; 78(4): 1092-1105, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37055018

RESUMO

BACKGROUND AND AIMS: Chronic liver disease is a growing epidemic, leading to fibrosis and cirrhosis. TGF-ß is the pivotal profibrogenic cytokine that activates HSC, yet other molecules can modulate TGF-ß signaling during liver fibrosis. Expression of the axon guidance molecules semaphorins (SEMAs), which signal through plexins and neuropilins (NRPs), have been associated with liver fibrosis in HBV-induced chronic hepatitis. This study aims at determining their function in the regulation of HSCs. APPROACH AND RESULTS: We analyzed publicly available patient databases and liver biopsies. We used transgenic mice, in which genes are deleted only in activated HSCs to perform ex vivo analysis and animal models. SEMA3C is the most enriched member of the semaphorin family in liver samples from patients with cirrhosis. Higher expression of SEMA3C in patients with NASH, alcoholic hepatitis, or HBV-induced hepatitis discriminates those with a more profibrotic transcriptomic profile. SEMA3C expression is also elevated in different mouse models of liver fibrosis and in isolated HSCs on activation. In keeping with this, deletion of SEMA3C in activated HSCs reduces myofibroblast marker expression. Conversely, SEMA3C overexpression exacerbates TGF-ß-mediated myofibroblast activation, as shown by increased SMAD2 phosphorylation and target gene expression. Among SEMA3C receptors, only NRP2 expression is maintained on activation of isolated HSCs. Interestingly, lack of NRP2 in those cells reduces myofibroblast marker expression. Finally, deletion of either SEMA3C or NRP2, specifically in activated HSCs, reduces liver fibrosis in mice. CONCLUSION: SEMA3C is a novel marker for activated HSCs that plays a fundamental role in the acquisition of the myofibroblastic phenotype and liver fibrosis.


Assuntos
Células Estreladas do Fígado , Semaforinas , Animais , Humanos , Camundongos , Células Estreladas do Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/patologia , Fosforilação , Semaforinas/genética , Semaforinas/metabolismo , Fator de Crescimento Transformador beta/metabolismo
2.
Acta Neuropathol ; 147(1): 75, 2024 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656399

RESUMO

In multiple sclerosis (MS), persisting disability can occur independent of relapse activity or development of new central nervous system (CNS) inflammatory lesions, termed chronic progression. This process occurs early and it is mostly driven by cells within the CNS. One promising strategy to control progression of MS is the inhibition of the enzyme Bruton's tyrosine kinase (BTK), which is centrally involved in the activation of both B cells and myeloid cells, such as macrophages and microglia. The benefit of BTK inhibition by evobrutinib was shown as we observed reduced pro-inflammatory activation of microglia when treating chronic experimental autoimmune encephalomyelitis (EAE) or following the adoptive transfer of activated T cells. Additionally, in a model of toxic demyelination, evobrutinib-mediated BTK inhibition promoted the clearance of myelin debris by microglia, leading to an accelerated remyelination. These findings highlight that BTK inhibition has the potential to counteract underlying chronic progression of MS.


Assuntos
Tirosina Quinase da Agamaglobulinemia , Encefalomielite Autoimune Experimental , Microglia , Bainha de Mielina , Piperidinas , Pirimidinas , Animais , Feminino , Camundongos , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Tirosina Quinase da Agamaglobulinemia/metabolismo , Compostos de Bifenilo/farmacologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Camundongos Endogâmicos C57BL , Microglia/patologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Bainha de Mielina/patologia , Bainha de Mielina/metabolismo , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Remielinização/fisiologia , Remielinização/efeitos dos fármacos
3.
J Chem Inf Model ; 64(14): 5691-5700, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38946265

RESUMO

The Caspase-based fusion protein technology (CASPON) allows for universal cleavage of fusion tags from proteins of interest to reconstitute the native N-terminus. While the CASPON enzyme has been optimized to be promiscuous against a diversity of N-terminal peptides, the cleavage efficacy for larger proteins can be surprisingly low. We develop an efficient means to rationalize and predict the cleavage efficiency based on a structural representation of the intrinsically disordered N-terminal peptides and their putative interactions with the CASPON enzyme. The number of favorably interacting N-terminal conformations shows a very good agreement with the experimentally observed cleavage efficiency, in agreement with a conformational selection model. The method relies on computationally cheap molecular dynamics simulations to efficiently generate a diverse collection of N-terminal conformations, followed by a simple fitting procedure into the CASPON enzyme. It can be readily used to assess the CASPON cleavability a priori.


Assuntos
Simulação de Dinâmica Molecular , Conformação Proteica , Caspases/metabolismo , Caspases/química , Especificidade por Substrato , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Peptídeos/química , Peptídeos/metabolismo
4.
Aging Clin Exp Res ; 36(1): 25, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321234

RESUMO

BACKGROUND: Sarcopenia is characterized by low muscle strength, decreased muscle mass, and decline in physical performance. While the measurements of muscle strength and physical performance are easy to perform, an accurate evaluation of muscle mass is technically more demanding. We therefore evaluated the suitability of calf circumference (CC) as a clinical indicator for muscle mass. METHODS: In a cross-sectional single-centre study, geriatric inpatients were assessed for sarcopenia according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) consensus. Calf circumference was tested for correlation with appendicular skeletal muscle mass index (ASMI). Receiver operating characteristic curves (ROC) were used to calculate the discriminatory value of the CC cut-off values to differentiate patients above and below ASMI cut-offs for sarcopenia. RESULTS: In this study population (n = 305, age 83.5 ± 7.0 years, BMI 25.7 kg/m2, 65.6% female), the prevalence of sarcopenia was 22.6%. In subjects with low ASMI, mean CC was 29.5 ± 3.4 cm for females and 32.0 ± 3.4 cm for males. A positive relationship between CC and ASMI was found. The optimized cut-off value for CC to identify patients with low ASMI was <31.5 cm for females (sensitivity 78%, specificity 79%), and <33.5 cm for males (sensitivity 71%, specificity 62%). CONCLUSION: In clinical settings where imaging technology for muscle mass quantification is not available, simple calf circumference measurement may be used as a dependable indicator for low muscle mass in older adults.


Assuntos
Sarcopenia , Masculino , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Sarcopenia/diagnóstico , Músculo Esquelético/fisiologia , Estudos Transversais , Força Muscular , Perna (Membro)/fisiologia , Força da Mão
5.
J Med Virol ; 95(10): e29122, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37787583

RESUMO

Despite recent advances in prophylactic vaccination, SARS-CoV-2 infections continue to cause significant morbidity. A better understanding of immune response differences between vaccinated individuals with and without later SARS-CoV-2 breakthrough infection is urgently needed. CoV-ADAPT is a prospective long-term study comparing humoral (anti-spike-RBD-IgG, neutralization capacity, avidity) and cellular (spike-induced T-cell interferon-γ [IFN-γ] release) immune responses in individuals vaccinated against SARS-CoV-2 at four different time points (three before and one after third vaccination). In this cohort study, 62 fully vaccinated individuals presented with SARS-CoV-2 breakthrough infections vs 151 without infection 3-7 months following third vaccination. Breakthrough infections significantly increased anti-spike-RBD-IgG (p < 0.01), but not spike-directed T-cell IFN-γ release (TC) or antibody avidity. Despite comparable surrogate neutralization indices, the functional neutralization capacity against SARS-CoV-2-assessed via a tissue culture-based assay-was significantly higher following breakthrough vs no breakthrough infection. Anti-spike-RBD-IgG and antibody avidity decreased with age (p < 0.01) and females showed higher anti-spike-RBD-IgG (p < 0.01), and a tendency towards higher antibody avidity (p = 0.051). The association between humoral and cellular immune responses previously reported at various time points was lost in subjects after breakthrough infections (p = 0.807). Finally, a machine-learning approach based on our large immunological dataset (a total of 49 variables) from different time points was unable to predict breakthrough infections (area under the curve: 0.55). In conclusion, distinct differences in humoral vs cellular immune responses in fully vaccinated individuals with or without breakthrough infection could be demonstrated. Breakthrough infections predominantly drive the humoral response without boosting the cellular component. Breakthrough infections could not be predicted based on immunological data, which indicates a superior role of environmental factors (e.g., virus exposure) in individualized risk assessment.


Assuntos
COVID-19 , Feminino , Humanos , SARS-CoV-2 , Infecções Irruptivas , Estudos de Coortes , Estudos Prospectivos , Interferon gama , Imunidade Celular , Imunoglobulina G , Anticorpos Antivirais , Vacinação , Imunidade Humoral
6.
Clin Chem Lab Med ; 61(3): 452-463, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36537103

RESUMO

OBJECTIVES: Conventionally, reference intervals are established by direct methods, which require a well-characterized, obviously healthy study population. This elaborate approach is time consuming, costly and has rarely been applied to steroid hormones measured by mass spectrometry. In this feasibility study, we investigate whether indirect methods based on routine laboratory results can be used to verify reference intervals from external sources. METHODS: A total of 11,259 serum samples were used to quantify 13 steroid hormones by mass spectrometry. For indirect estimation of reference intervals, we applied a "modified Hoffmann approach", and verified the results with a more sophisticated statistical method (refineR). We compared our results with those of four recent studies using direct approaches. RESULTS: We evaluated a total of 81 sex- and age-specific reference intervals, for which at least 120 measurements were available. The overall agreement between indirectly and directly determined reference intervals was surprisingly good as nearly every fourth reference limit could be confirmed by narrow tolerance limits. Furthermore, lower reference limits could be provided for some low concentrated hormones by the indirect method. In cases of substantial deviations, our results matched the underlying data better than reference intervals from external studies. CONCLUSIONS: Our study shows for the first time that indirect methods are a valuable tool to verify existing reference intervals for steroid hormones. A simple "modified Hoffmann approach" based on the general assumption of a normal or lognormal distribution model is sufficient for screening purposes, while the refineR algorithm may be used for a more detailed analysis.


Assuntos
Esteroides , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Valores de Referência , Hormônios , Fatores Etários
7.
Surg Endosc ; 37(10): 8104-8115, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37658201

RESUMO

BACKGROUND: A direct comparison of the cost-benefit analysis of retroperitoneoscopic adrenalectomy (RPA) versus the minimally invasive transperitoneal access (LTA) approach is currently lacking. We hypothesized that RPA is more cost effective than LTA; promising significant savings for the healthcare system in an era of ever more limited resources. METHODS: We performed a monocentric retrospective observational cohort study based on data from our Endocrine Surgery Registry. Patients who were operated upon between 2019 and 2022 were included. After pair-matching, both cohorts (RPA vs. LTA) were compared for perioperative variables and treatment costs (process cost calculation), revenue and profit. RESULTS: Two homogenous cohorts of 43 patients each (RPA vs. LTA) were identified following matching. Patient characteristics between the cohorts were comparable. In terms of both treatment-associated costs and profit, the RPA procedure was superior to LTA (costs: US$5789.99 for RPA vs. US$6617.75 for LTA, P = 0.043; profit: US$1235.59 for RPA vs. US$653.33 for LTA, P = 0.027). The duration of inpatient treatment and comorbidities significantly influenced the cost of treatment and the overall profit. CONCLUSIONS: RPA appears not only to offer benefits over LTA in terms of perioperative morbidity and length of hospital stay, but also has a superior financial cost/benefit profile.


Assuntos
Neoplasias das Glândulas Suprarrenais , Laparoscopia , Humanos , Laparoscopia/métodos , Neoplasias das Glândulas Suprarrenais/cirurgia , Estudos Retrospectivos , Adrenalectomia/métodos , Tempo de Internação
8.
Appl Opt ; 62(14): 3724-3736, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706990

RESUMO

For coherent light illumination, surface roughness leads to speckles in the scattered light image. By evaluating the speckle contrast or image auto-correlation, a measurement of the roughness parameter S q is possible. While these measurement principles have been well known for decades, a fundamental understanding of the minimal achievable measurement uncertainty is missing. Therefore, the measurement uncertainty limits for four unavoidable sources of uncertainty are derived by means of theoretical and numerical approaches. The study is focused on the case of monochromatic speckles, which provide the highest sensitivity, as well as on the case of planar surface and isotropic surface roughness with a Gaussian height distribution and Gaussian correlation function. The considered uncertainty sources are the natural randomness of surface roughness itself, speckle noise, quantum shot noise, and camera noise. As a result, for the studied experimental configuration, speckle noise is determined as the largest contribution to measurement uncertainty, which leads to a minimal achievable relative uncertainty of 1%-2% for S q =(0.03-0.15)λ. According to theoretical studies, the speckle noise limit of the relative uncertainty is inversely proportional to four times the square root of the independent number of evaluated speckles. In addition, an absolute uncertainty limit is reached for ever-smoother surfaces, which amounts to λ divided by 64 times the square root of the independent number of evaluated speckles. Furthermore, systematic errors due to cross-sensitivity with respect to other parameters of surface roughness (height distribution, correlation length) as well as the surface position and shape (axial offset, tilt, curvature) are quantified and discussed. For the considered small deviations of different influencing quantities, the quantified errors are one order of magnitude smaller than the speckle noise limit.

9.
J Acoust Soc Am ; 154(2): 1299-1314, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37650781

RESUMO

The modeling of sound propagation for land-based wind turbines is a complex task that takes various parameters into account. Not only do the wind speed and wind direction affect the noise received at a certain position by changing the refraction of the sound, but also the terrain complexity, ground impedance, and receiver position relative to the source and ground all affect propagation. These effects are seen by the reflections of the sound at the ground surface causing interference of sound waves, or by the receiver being positioned in and out of noise shadow zones in the upwind far field position, or in steep terrain irregularities. Several sound propagation models with different levels of fidelity have been developed through time to account for these effects. This paper will focus on two different parabolic equation models, the Beilis-Tappert Parabolic Equation and the Generalized Terrain Parabolic Equation, through theoretical studies of varying terrain complexity, ground impedance, and sound speed profiles (upwind, downwind, and no wind). In addition, the propagation models are validated through spectral comparisons to noise measurements from two different campaigns considering loudspeaker noise and wind turbine noise, respectively.

10.
Sensors (Basel) ; 23(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37896687

RESUMO

As incrementally formed sheets show large geometric deviations resulting from the deflection of the forming tool, an in-process measurement of the tool tip position is required. In order to cover a measuring volume of 2.0 m × 1.0 m × 0.2 m and to achieve measuring uncertainties of less than 50 µm, a multi-sensor system based on triangulation is realized. Each shadow imaging sensor in the multi-sensor system evaluates the direction vector to an LED attached to the tool, and the three-dimensional position of the LED is then determined from the combination of two sensors. Experimental results show that the angle of view from the sensor to the LED limits both the measurement range and the measurement uncertainty. The measurement uncertainty is dominated by systematic deviations, but these can be compensated, so that the measurement uncertainty required for measuring the tool tip position in the ISF is achieved.

11.
J Biol Chem ; 297(4): 101095, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34418435

RESUMO

Proteases serve as important tools in biotechnology and as valuable drugs or drug targets. Efficient protein engineering methods to study and modulate protease properties are thus of great interest for a plethora of applications. We established PROFICS (PRotease Optimization via Fusion-Inhibited Carbamoyltransferase-based Selection), a bacterial selection system, which enables the optimization of proteases for biotechnology, therapeutics or diagnosis in a simple overnight process. During the PROFICS process, proteases are selected for their ability to specifically cut a tag from a reporter enzyme and leave a native N-terminus. Precise and efficient cleavage after the recognition sequence reverses the phenotype of an Escherichia coli knockout strain deficient in an essential enzyme of pyrimidine synthesis. A toolbox was generated to select for proteases with different preferences for P1' residues (the residue immediately following the cleavage site). The functionality of PROFICS is demonstrated with viral proteases and human caspase-2. PROFICS improved caspase-2 activity up to 25-fold after only one round of mutation and selection. Additionally, we found a significantly improved tolerance for all P1' residues caused by a mutation in a substrate interaction site. We showed that this improved activity enables cells containing the new variant to outgrow cells containing all other mutants, facilitating its straightforward selection. Apart from optimizing enzymatic activity and P1' tolerance, PROFICS can be used to reprogram specificities, erase off-target activity, optimize expression via tags/codon usage, or even to screen for potential drug-resistance-conferring mutations in therapeutic targets such as viral proteases in an unbiased manner.


Assuntos
Caspase 2 , Cisteína Endopeptidases , Evolução Molecular Direcionada , Escherichia coli , Engenharia de Proteínas , Caspase 2/biossíntese , Caspase 2/química , Caspase 2/genética , Cisteína Endopeptidases/biossíntese , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Humanos
12.
Opt Express ; 30(8): 12615-12629, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472895

RESUMO

With well-known speckle measurement techniques, the root mean square height as well as the autocorrelation length of isotropic surfaces can be determined quickly and over a large area of interest. Beyond that, the present article studies the speckle-based measurement of anisotropic surfaces. For this purpose, a measurement setup and evaluation algorithm are presented that enable the characterization of unidirectionally anisotropic surfaces machined by grinding. As a result, four measurands are obtained from one speckle image: the machining direction, the autocorrelation length perpendicular to the machining direction, as well as two root mean square roughness parameters parallel and perpendicular to the machining direction. The first two measurands are obtained from a two-dimensional fast Fourier transform of the diffraction pattern resulting from the unidirectional tool marks and the latter two by a bidirectional evaluation of the speckle contrast. In addition to measurements on physical reference samples, a spatial light modulator is used to create a large number of surface topographies with known model parameters in order to quantify the measurement uncertainty.

13.
J Exp Bot ; 73(19): 6816-6837, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918065

RESUMO

Leaf senescence is a developmental process allowing nutrient remobilization to sink organs. We characterized flag leaf senescence at 7, 14, and 21 d past anthesis in two near-isogenic barley lines varying in the allelic state of the HvNAM1 transcription factor gene, which influences senescence timing. Metabolomics and microscopy indicated that, as senescence progressed, thylakoid lipids were transiently converted to neutral lipids accumulating in lipid droplets. Senescing leaves also exhibited an accumulation of sugars including glucose, while nitrogen compounds (nucleobases, nucleotides, and amino acids) decreased. RNA-Seq analysis suggested lipid catabolism via ß-oxidation and the glyoxylate cycle, producing carbon skeletons and feeding respiration as a replacement of the diminished carbon supply from photosynthesis. Comparison of the two barley lines highlighted a more prominent up-regulation of heat stress transcription factor- and chaperone-encoding genes in the late-senescing line, suggesting a role for these genes in the control of leaf longevity. While numerous genes with putative roles in nitrogen remobilization were up-regulated in both lines, several peptidases, nucleases, and nitrogen transporters were more highly induced in the early-senescing line; this finding identifies processes and specific candidates which may affect nitrogen remobilization from senescing barley leaves, downstream of the HvNAM1 transcription factor.


Assuntos
Hordeum , Hordeum/genética , Hordeum/metabolismo , Nitrogênio/metabolismo , Proteostase , Senescência Vegetal , Folhas de Planta/metabolismo , Carbono/metabolismo , Fatores de Transcrição/metabolismo , Lipídeos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
14.
Phys Rev Lett ; 129(16): 167701, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306758

RESUMO

We present a microscopic model for a singly charged quantum dot (QD) ensemble to reveal the origin of the long-range effective interaction between the electron spins in the QDs. Wilson's numerical renormalization group (NRG) is used to calculate the magnitude and the spatial dependency of the effective spin-spin interaction mediated by the growth-induced wetting layer. Surprisingly, we found an antiferromagnetic Heisenberg coupling for very short inter-QD distances that is caused by the significant particle-hole asymmetry of the wetting layer band at very low filling. Using the NRG results obtained from realistic parameters as input for a semiclassical simulation for a large QD ensemble, we demonstrate that the experimentally reported phase shifts in the coherent spin dynamics between single- and two-color laser pumping can be reproduced by our model, solving a long-standing open problem of the microscopic origin of the inter-QD electron spin-spin interaction.

15.
Allergy ; 77(8): 2381-2392, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35124800

RESUMO

BACKGROUND: Homologous and heterologous SARS-CoV-2 vaccinations yield different spike protein-directed humoral and cellular immune responses. This study aimed to explore their currently unknown interdependencies. METHODS: COV-ADAPT is a prospective, observational cohort study of 417 healthcare workers who received vaccination with homologous ChAdOx1 nCoV-19, homologous BNT162b2 or with heterologous ChAdOx1 nCoV-19/BNT162b2. We assessed humoral (anti-spike-RBD-IgG, neutralizing antibodies, and avidity) and cellular (spike-induced T-cell interferon-γ release) immune responses in blood samples up to 2 weeks before (T1) and 2-12 weeks following secondary immunization (T2). RESULTS: Initial vaccination with ChAdOx1 nCoV-19 resulted in lower anti-spike-RBD-IgG compared with BNT162b2 (70 ± 114 vs. 226 ± 279 BAU/ml, p < .01) at T1. Booster vaccination with BNT162b2 proved superior to ChAdOx1 nCoV-19 at T2 (anti-spike-RBD-IgG: ChAdOx1 nCoV-19/BNT162b2 2387 ± 1627 and homologous BNT162b2 3202 ± 2184 vs. homologous ChAdOx1 nCoV-19 413 ± 461 BAU/ml, both p < .001; spike-induced T-cell interferon-γ release: ChAdOx1 nCoV-19/BNT162b2 5069 ± 6733 and homologous BNT162b2 4880 ± 7570 vs. homologous ChAdOx1 nCoV-19 1152 ± 2243 mIU/ml, both p < .001). No significant differences were detected between BNT162b2-boostered groups at T2. For ChAdOx1 nCoV-19, no booster effect on T-cell activation could be observed. We found associations between anti-spike-RBD-IgG levels (ChAdOx1 nCoV-19/BNT162b2 and homologous BNT162b2) and T-cell responses (homologous ChAdOx1 nCoV-19 and ChAdOx1 nCoV-19/BNT162b2) from T1 to T2. Additionally, anti-spike-RBD-IgG and T-cell response were linked at both time points (all groups combined). All regimes yielded neutralizing antibodies and increased antibody avidity at T2. CONCLUSIONS: Interdependencies between humoral and cellular immune responses differ between common SARS-CoV-2 vaccination regimes. T-cell activation is unlikely to compensate for poor humoral responses.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Imunidade Celular , Imunidade Humoral , Anticorpos Neutralizantes , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , ChAdOx1 nCoV-19 , Humanos , Imunoglobulina G , Interferon gama , Estudos Prospectivos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinação
16.
J Magn Reson Imaging ; 55(1): 246-254, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34323329

RESUMO

BACKGROUND: Quiescent-interval slice-selective (QISS) magnetic resonance angiography (MRA) is a non-contrast alternative for the pre-procedural assessment of patients with peripheral artery disease (PAD). However, the feasibility of pre-procedural stent size estimation using QISS MRA would merit investigation. PURPOSE: To evaluate the feasibility of QISS MRA for pre-procedural stent size estimation in PAD patients compared to computed tomography angiography (CTA). STUDY TYPE: Retrospective. SUBJECTS: Thirty-three PAD patients (68 ± 9 years, 18 men, 15 women). FIELD STRENGTH/SEQUENCE: Two-dimensional balanced steady-state free precession QISS MRA at 1.5 T and 3 T. ASSESSMENT: All patients received QISS MRA and CTA of the lower extremity run-off followed by interventional digital subtraction angiography (DSA). Stenotic lesion length and diameter were quantified (AMF and AVS with 3 and 13 years of experience in cardiovascular imaging, respectively) to estimate the dimensions of the stent necessary to restore blood flow in the treated arteries. Measured dimensions were adjusted to the closest stent size available. STATISTICAL TESTS: The Friedman test with subsequent pairwise Wilcoxon signed-rank test was used to compare the estimated stent dimensions between QISS MRA, CTA, and the physical stent size used for intervention. Intra-class correlation (ICC) analysis was performed to assess inter-reader agreement. Significant differences were considered at P < 0.05. RESULTS: No significant difference was observed between estimated stent diameter by QISS MRA or CTA compared to physical stent diameter (8.9 ± 2.9 mm, 8.8 ± 3.0 mm, and 8.8 ± 3.8 mm, respectively; χ2  = 1.45, P = 0.483). There was a significant underestimation of stent length for both QISS MRA and CTA, compared to physical stent length (45.8 ± 27.8 mm, 46.4 ± 29.3 mm, and 50.4 ± 34.0 mm, respectively; χ2  = 11.96) which could be corrected when measurements were adjusted to the next available stent length (χ2  = 2.38, P = 0.303). Inter-reader assessment showed good to excellent agreement between the readers (all ICC ≥0.81). DATA CONCLUSION: QISS MRA represents a reliable method for pre-procedural lesion assessment and stent diameter and length estimation in PAD patients. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Doença Arterial Periférica , Humanos , Doença Arterial Periférica/diagnóstico por imagem , Estudos Retrospectivos , Stents
17.
FASEB J ; 35(9): e21831, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383982

RESUMO

The nuclear factor of activated T-cells 5 (NFAT5) is a transcriptional regulator of macrophage activation and T-cell development, which controls stabilizing responses of cells to hypertonic and biomechanical stress. In this study, we detected NFAT5 in the media layer of arteries adjacent to human arteriosclerotic plaques and analyzed its role in vascular smooth muscle cells (VSMCs) known to contribute to arteriosclerosis through the uptake of lipids and transformation into foam cells. Exposure of both human and mouse VSMCs to cholesterol stimulated the nuclear translocation of NFAT5 and increased the expression of the ATP-binding cassette transporter Abca1, required to regulate cholesterol efflux from cells. Loss of Nfat5 promoted cholesterol accumulation in these cells and inhibited the expression of genes involved in the management of oxidative stress or lipid handling, such as Sod1, Plin2, Fabp3, and Ppard. The functional relevance of these observations was subsequently investigated in mice fed a high-fat diet upon induction of a smooth muscle cell-specific genetic ablation of Nfat5 (Nfat5(SMC)-/- ). Under these conditions, Nfat5(SMC)-/- but not Nfat5fl/fl mice developed small, focal lipid-rich lesions in the aorta after 14 and 25 weeks, which were formed by intracellular lipid droplets deposited in the sub-intimal VSMCs layer. While known for being activated by external stimuli, NFAT5 was found to mediate the expression of VSMC genes associated with the handling of lipids in response to a cholesterol-rich environment. Failure of this protective function may promote the formation of lipid-laden arterial VSMCs and pro-atherogenic vascular responses.


Assuntos
Aorta/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipídeos/fisiologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fatores de Transcrição/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Idoso , Animais , Aterosclerose/metabolismo , Células Cultivadas , Colesterol/metabolismo , Feminino , Células Espumosas/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Hipercolesterolemia/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Túnica Íntima/metabolismo
18.
Clin Chem Lab Med ; 60(7): 1031-1038, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35451300

RESUMO

OBJECTIVES: Thyroid-stimulating hormone (TSH) is the routine primary screening test to assess thyroid function and rapid measurement of TSH levels is highly desirable especially in emergency situations. In the present study, we compared the analytical performance of a commercially available point-of-care test (AFIAS-1) and five laboratory-based systems. METHODS: Left over material of 60 patient plasma samples was collected from patient care and used in the respective assay. For statistical analysis of the produced data Bland-Altman and Passing-Bablok regression analysis were applied. RESULTS: Good correlation (r=0.982 or higher) was found between all devices. Slopes from regression analysis ranged from 0.972 (95% CI: 0.927-1.013) to 1.276 (95% CI: 1.210-1.315). Among the compared devices, imprecision was high in terms of coefficient of variation (CV=10.3%) for low TSH concentrations and lower (CV=7.3%) for high TSH concentrations. Independent of the method used, we demonstrated a poor standardization of TSH assays, which might impact clinical diagnosis e.g. of hyperthyreosis. CONCLUSIONS: This study shows that the point-of-care (POC) test AFIAS-1 can serve as an alternative to laboratory-based assays. In addition the data imply that better standardization of TSH measurements is needed.


Assuntos
Testes Imediatos , Tireotropina , Humanos , Padrões de Referência
19.
Mol Breed ; 42(10): 59, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37313013

RESUMO

Malt barley (Hordeum vulgare L.) is an important cash crop with stringent grain quality standards. Timing of the switch from vegetative to reproductive growth and timing of whole-plant senescence and nutrient remobilization are critical for cereal grain yield and quality. Understanding the genetic variation in genes associated with these developmental traits can streamline genotypic selection of superior malt barley germplasm. Here, we determined the effects of allelic variation in three genes encoding a glycine-rich RNA-binding protein (HvGR-RBP1) and two NAC transcription factors (HvNAM1 and HvNAM2) on malt barley agronomics and quality using previously developed markers for HvGR-RBP1 and HvNAM1 and a novel marker for HvNAM2. Based on a single-nucleotide polymorphism (SNP) in the first intron, the utilized marker differentiates NAM2 alleles of low-grain protein variety 'Karl' and of higher protein variety 'Lewis'. We demonstrate that the selection of favorable alleles for each gene impacts heading date, senescence timing, grain size, grain protein concentration, and malt quality. Specifically, combining 'Karl' alleles for the two NAC genes with the 'Lewis' HvGR-RBP1 allele extends grain fill duration, increases the percentage of plump kernels, decreases grain protein, and provides malt quality stability. Molecular markers for these genes are therefore highly useful tools in malt barley breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01331-7.

20.
Surg Endosc ; 36(5): 2954-2961, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34129089

RESUMO

BACKGROUND: A recently developed haemostatic peptide gel for endoscopic application has been introduced to improve the management of gastrointestinal bleeding. The aim of this pilot study was to evaluate the feasibility, safety, efficacy and indication profiles of PuraStat in a clinical setting. METHODS: In this prospective observational multicentre pilot study, patients with acute non-variceal gastrointestinal bleeding (upper and lower) were included. Primary and secondary application of PuraStat was evaluated. Haemoglobin, prothrombin time, platelets and transfusion behaviour were documented before and after haemostasis. The efficacy of PuraStat was assessed during the procedure, at 3 days and 1 week after application. RESULTS: 111 patients with acute gastrointestinal bleeding were recruited into the study. 70 percent (78/111) of the patients had upper gastrointestinal bleeding and 30% (33/111) had lower gastrointestinal bleeding. After primary application of PuraStat, initial haemostatic success was achieved in 94% of patients (74/79, 95% CI 88-99%), and in 75% of the patients when used as a secondary haemostatic product, following failure of established techniques (24/32, 95% CI 59-91%). The therapeutic success rates (absence of rebleeding) after 3 and 7 days were 91% and 87% after primary use, and 87% and 81% in all study patients. Overall rebleeding rate at 30 day follow-up was 16% (18/111). In the 5 patients who finally required surgery (4.5%), PuraStat allowed temporary haemostasis and stabilisation. CONCLUSIONS: PuraStat expanded the therapeutic toolbox available for an effective treatment of gastrointestinal bleeding sources. It could be safely applied and administered without complications as a primary or secondary therapy. PuraStat may additionally serve as a bridge to surgery in order to achieve temporary haemostasis in case of refractory severe bleeding, possibly playing a role in preventing immediate emergency surgery.


Assuntos
Hemostase Endoscópica , Hemostáticos , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Hemostase Endoscópica/métodos , Hemostáticos/uso terapêutico , Humanos , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
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