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1.
N Engl J Med ; 386(26): 2459-2470, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35709019

RESUMEN

BACKGROUND: Intravenous fluids are recommended for the treatment of patients who are in septic shock, but higher fluid volumes have been associated with harm in patients who are in the intensive care unit (ICU). METHODS: In this international, randomized trial, we assigned patients with septic shock in the ICU who had received at least 1 liter of intravenous fluid to receive restricted intravenous fluid or standard intravenous fluid therapy; patients were included if the onset of shock had been within 12 hours before screening. The primary outcome was death from any cause within 90 days after randomization. RESULTS: We enrolled 1554 patients; 770 were assigned to the restrictive-fluid group and 784 to the standard-fluid group. Primary outcome data were available for 1545 patients (99.4%). In the ICU, the restrictive-fluid group received a median of 1798 ml of intravenous fluid (interquartile range, 500 to 4366); the standard-fluid group received a median of 3811 ml (interquartile range, 1861 to 6762). At 90 days, death had occurred in 323 of 764 patients (42.3%) in the restrictive-fluid group, as compared with 329 of 781 patients (42.1%) in the standard-fluid group (adjusted absolute difference, 0.1 percentage points; 95% confidence interval [CI], -4.7 to 4.9; P = 0.96). In the ICU, serious adverse events occurred at least once in 221 of 751 patients (29.4%) in the restrictive-fluid group and in 238 of 772 patients (30.8%) in the standard-fluid group (adjusted absolute difference, -1.7 percentage points; 99% CI, -7.7 to 4.3). At 90 days after randomization, the numbers of days alive without life support and days alive and out of the hospital were similar in the two groups. CONCLUSIONS: Among adult patients with septic shock in the ICU, intravenous fluid restriction did not result in fewer deaths at 90 days than standard intravenous fluid therapy. (Funded by the Novo Nordisk Foundation and others; CLASSIC ClinicalTrials.gov number, NCT03668236.).


Asunto(s)
Fluidoterapia , Choque Séptico , Administración Intravenosa , Adulto , Cuidados Críticos/métodos , Fluidoterapia/efectos adversos , Fluidoterapia/métodos , Humanos , Unidades de Cuidados Intensivos , Choque Séptico/mortalidad , Choque Séptico/terapia
2.
Anal Chem ; 96(10): 4171-4179, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38358916

RESUMEN

We present an integrated, open-source device for parahydrogen-based hyperpolarization processes in the microtesla field regime with a cost of components of less than $7000. The device is designed to produce a batch of 13C and 15N hyperpolarized (HP) compounds via hydrogenative or non-hydrogenative parahydrogen-induced polarization methods that employ microtesla magnetic fields for efficient polarization transfer of parahydrogen-derived spin order to X-nuclei (e.g., 13C and 15N). The apparatus employs a layered structure (reminiscent of a Russian doll "Matryoshka") that includes a nonmagnetic variable-temperature sample chamber, a microtesla magnetic field coil (operating in the range of 0.02-75 microtesla), a three-layered mu-metal shield (to attenuate the ambient magnetic field), and a magnetic shield degaussing coil placed in the overall device enclosure. The gas-handling manifold allows for parahydrogen-gas flow and pressure control (up to 9.2 bar of total parahydrogen pressure). The sample temperature can be varied either using a water bath or a PID-controlled heat exchanger in the range from -12 to 80 °C. This benchtop device measures 62 cm (length) × 47 cm (width) × 47 cm (height), weighs 30 kg, and requires only connections to a high-pressure parahydrogen gas supply and a single 110/220 VAC power source. The utility of the device has been demonstrated using an example of parahydrogen pairwise addition to form HP ethyl [1-13C]acetate (P13C = 7%, [c] = 1 M). Moreover, the Signal Amplification By Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) technique was employed to demonstrate efficient hyperpolarization of 13C and 15N spins in a wide range of biologically relevant molecules, including [1-13C]pyruvate (P13C = 14%, [c] = 27 mM), [1-13C]-α-ketoglutarate (P13C = 17%), [1-13C]ketoisocaproate (P13C = 18%), [15N3]metronidazole (P15N = 13%, [c] = 20 mM), and others. While the vast majority of the utility studies have been performed in standard 5 mm NMR tubes, the sample chamber of the device can accommodate a wide range of sample container sizes and geometries of up to 1 L sample volume. The device establishes an integrated, simple, inexpensive, and versatile equipment gateway needed to facilitate parahydrogen-based hyperpolarization experiments ranging from basic science to preclinical applications; indeed, detailed technical drawings and a bill of materials are provided to support the ready translation of this design to other laboratories.

3.
Brief Bioinform ; 23(6)2022 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-36305426

RESUMEN

The ongoing coronavirus disease 2019 (COVID-19) pandemic has highlighted the need to better understand virus-host interactions. We developed a network-based method that expands the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-host protein interaction network and identifies host targets that modulate viral infection. To disrupt the SARS-CoV-2 interactome, we systematically probed for potent compounds that selectively target the identified host proteins with high expression in cells relevant to COVID-19. We experimentally tested seven chemical inhibitors of the identified host proteins for modulation of SARS-CoV-2 infection in human cells that express ACE2 and TMPRSS2. Inhibition of the epigenetic regulators bromodomain-containing protein 4 (BRD4) and histone deacetylase 2 (HDAC2), along with ubiquitin-specific peptidase (USP10), enhanced SARS-CoV-2 infection. Such proviral effect was observed upon treatment with compounds JQ1, vorinostat, romidepsin and spautin-1, when measured by cytopathic effect and validated by viral RNA assays, suggesting that the host proteins HDAC2, BRD4 and USP10 have antiviral functions. We observed marked differences in antiviral effects across cell lines, which may have consequences for identification of selective modulators of viral infection or potential antiviral therapeutics. While network-based approaches enable systematic identification of host targets and selective compounds that may modulate the SARS-CoV-2 interactome, further developments are warranted to increase their accuracy and cell-context specificity.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , SARS-CoV-2 , Humanos , Mapas de Interacción de Proteínas , Proteínas Nucleares , Factores de Transcripción , Antivirales/farmacología , Ubiquitina Tiolesterasa , Proteínas de Ciclo Celular
4.
Magn Reson Med ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164797

RESUMEN

PURPOSE: To demonstrate the feasibility of 3D echo-planar spectroscopic imaging (EPSI) technique with rapid volumetric radial k-space sampling for hyperpolarized (HP) 13C magnetic resonance spectroscopic imaging (MRSI) in vivo. METHODS: A radial EPSI (rEPSI) was implemented on a 3 T clinical PET/MR system. To enable volumetric coverage, the sinusoidal shaped readout gradients per k-t-spoke were rotated along the three spatial dimensions in a golden-angle like manner. A distance-weighted, density-compensated gridding reconstruction was used, also in cases with undersampling of spokes in k-space. Measurements without and with HP 13C-labeled substances were performed in phantoms and rats using a double-resonant 13C/1H volume resonator with 72 mm inner diameter. RESULTS: Phantom measurements demonstrated the feasibility of the implemented rEPSI sequence, as well as the robustness to undersampling in k-space up to a factor of 5 without advanced reconstruction techniques. Applied to measurements with HP [1-13C]pyruvate in a tumor-bearing rat, we obtained well-resolved MRSI datasets with a large matrix size of 123 voxels covering the whole imaging FOV of (180 mm)3 within 6.3 s, enabling to observe metabolism in dynamic acquisitions. CONCLUSION: After further optimization, the proposed rEPSI method may be useful in applications of HP 13C-tracers where unknown or varying metabolite resonances are expected, and the acquisition of dynamic, volumetric MRSI datasets with an adequate temporal resolution is a challenge.

5.
Transpl Int ; 37: 13191, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015154

RESUMEN

Little is known either about either physical activity patterns, or other lifestyle-related prevention measures in heart transplantation (HTx) recipients. The history of HTx started more than 50 years ago but there are still no guidelines or position papers highlighting the features of prevention and rehabilitation after HTx. The aims of this scientific statement are (i) to explain the importance of prevention and rehabilitation after HTx, and (ii) to promote the factors (modifiable/non-modifiable) that should be addressed after HTx to improve patients' physical capacity, quality of life and survival. All HTx team members have their role to play in the care of these patients and multidisciplinary prevention and rehabilitation programmes designed for transplant recipients. HTx recipients are clearly not healthy disease-free subjects yet they also significantly differ from heart failure patients or those who are supported with mechanical circulatory support. Therefore, prevention and rehabilitation after HTx both need to be specifically tailored to this patient population and be multidisciplinary in nature. Prevention and rehabilitation programmes should be initiated early after HTx and continued during the entire post-transplant journey. This clinical consensus statement focuses on the importance and the characteristics of prevention and rehabilitation designed for HTx recipients.


Asunto(s)
Insuficiencia Cardíaca , Trasplante de Corazón , Calidad de Vida , Humanos , Consenso , Europa (Continente) , Ejercicio Físico , Insuficiencia Cardíaca/rehabilitación , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/efectos adversos , Sociedades Médicas
6.
Proc Natl Acad Sci U S A ; 118(17)2021 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-33850049

RESUMEN

Depression is a widespread and devastating mental illness and the search for rapid-acting antidepressants remains critical. There is now exciting evidence that the psychedelic compound psilocybin produces not only powerful alterations of consciousness, but also rapid and persistent antidepressant effects. How psilocybin exerts its therapeutic actions is not known, but it is widely presumed that these actions require altered consciousness, which is known to be dependent on serotonin 2A receptor (5-HT2AR) activation. This hypothesis has never been tested, however. We therefore asked whether psilocybin would exert antidepressant-like responses in mice and, if so, whether these responses required 5-HT2AR activation. Using chronically stressed male mice, we observed that a single injection of psilocybin reversed anhedonic responses assessed with the sucrose preference and female urine preference tests. The antianhedonic response to psilocybin was accompanied by a strengthening of excitatory synapses in the hippocampus-a characteristic of traditional and fast-acting antidepressants. Neither behavioral nor electrophysiological responses to psilocybin were prevented by pretreatment with the 5-HT2A/2C antagonist ketanserin, despite positive evidence of ketanserin's efficacy. We conclude that psilocybin's mechanism of antidepressant action can be studied in animal models and suggest that altered perception may not be required for its antidepressant effects. We further suggest that a 5-HT2AR-independent restoration of synaptic strength in cortico-mesolimbic reward circuits may contribute to its antidepressant action. The possibility of combining psychedelic compounds and a 5-HT2AR antagonist offers a potential means to increase their acceptance and clinical utility and should be studied in human depression.


Asunto(s)
Depresión/tratamiento farmacológico , Alucinógenos/uso terapéutico , Hipocampo/efectos de los fármacos , Psilocibina/uso terapéutico , Receptores de Serotonina 5-HT2 , Animales , Depresión/etiología , Evaluación Preclínica de Medicamentos , Alucinógenos/farmacología , Ketanserina , Masculino , Ratones Endogámicos C57BL , Psilocibina/farmacología , Agonistas del Receptor de Serotonina 5-HT2/análisis , Estrés Psicológico/complicaciones
7.
Skeletal Radiol ; 53(7): 1319-1332, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38240761

RESUMEN

OBJECTIVE: To qualitatively and quantitatively evaluate the 2.5-year MRI outcome after Matrix-associated autologous chondrocyte implantation (MACI) at the patella, reconstruction of the medial patellofemoral ligament (MPFL), and combined procedures. METHODS: In 66 consecutive patients (age 22.8 ± 6.4years) with MACI at the patella (n = 16), MPFL reconstruction (MPFL; n = 31), or combined procedures (n = 19) 3T MRI was performed 2.5 years after surgery. For morphological MRI evaluation WORMS and MOCART scores were obtained. In addition quantitative cartilage T2 and T1rho relaxation times were acquired. Several clinical scores were obtained. Statistical analyses included descriptive statistics, Mann-Whitney-U-tests and Pearson correlations. RESULTS: WORMS scores at follow-up (FU) were significantly worse after combined procedures (8.7 ± 4.9) than after isolated MACI (4.3 ± 3.6, P = 0.005) and after isolated MPFL reconstruction (5.3 ± 5.7, P = 0.004). Bone marrow edema at the patella in the combined group was the only (non-significantly) worsening WORMS parameter from pre- to postoperatively. MOCART scores were significantly worse in the combined group than in the isolated MACI group (57 ± 3 vs 88 ± 9, P < 0.001). Perfect defect filling was achieved in 26% and 69% of cases in the combined and MACI group, respectively (P = 0.031). Global and patellar T2 values were higher in the combined group (Global T2: 34.0 ± 2.8ms) and MACI group (35.5 ± 3.1ms) as compared to the MPFL group (31.1 ± 3.2ms, P < 0.05). T2 values correlated significantly with clinical scores (P < 0.005). Clinical Cincinnati scores were significantly worse in the combined group (P < 0.05). CONCLUSION: After combined surgery with patellar MACI and MPFL reconstruction inferior MRI outcomes were observed than after isolated procedures. Therefore, patients with need for combined surgery may be at particular risk for osteoarthritis.


Asunto(s)
Imagen por Resonancia Magnética , Rótula , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Femenino , Resultado del Tratamiento , Rótula/diagnóstico por imagen , Rótula/cirugía , Adulto , Condrocitos/trasplante , Trasplante Autólogo , Adulto Joven , Articulación Patelofemoral/diagnóstico por imagen , Articulación Patelofemoral/cirugía , Procedimientos de Cirugía Plástica/métodos , Ligamentos Articulares/diagnóstico por imagen , Ligamentos Articulares/cirugía , Adolescente
8.
Eur Heart J ; 44(35): 3327-3335, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37387689

RESUMEN

AIMS: Management of patients with atrial fibrillation (AF) and concomitant heart failure (HF) remains complex. The Antwerp score, based on four parameters [QRS >120 ms (2 points), known aetiology (2 points), paroxysmal AF (1 point), severe atrial dilation (1 point)] adequately estimated the probability of left ventricular ejection fraction (LVEF) recovery after AF ablation in a single-centre cohort. The present study aims to externally validate this prediction model in a large European multi-centre cohort. METHODS AND RESULTS: A total of 605 patients (61.1 ± 9.4 years, 23.8% females, 79.8% with persistent AF) with HF and impaired LVEF (<50%) undergoing AF ablation in 8 European centres were retrospectively identified. According to the LVEF changes at 12-month echocardiography, 427 (70%) patients fulfilled the '2021 Universal Definition of HF' criteria for LVEF recovery and were defined as 'responders'. External validation of the score yielded good discrimination and calibration {area under the curve 0.86 [95% confidence interval (CI) 0.82-0.89], P < .001; Hosmer-Lemeshow P = .29}. Patients with a score < 2 had a 93% probability of LVEF recovery as opposed to only 24% in patients with a score > 3. Responders experienced more often positive ventricular remodelling [odds ratio (OR) 8.91, 95% CI 4.45-17.84, P < .001], fewer HF hospitalizations (OR 0.09, 95% CI 0.05-0.18, P < .001) and lower mortality (OR 0.11, 95% CI 0.04-0.31, P < .001). CONCLUSION: In this multi-centre study, a simple four-parameter score predicted LVEF recovery after AF ablation in patients with HF and discriminated clinical outcomes. These findings support the use of the Antwerp score to standardize shared decision-making regarding AF ablation referral in future clinical studies.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Insuficiencia Cardíaca , Femenino , Humanos , Masculino , Fibrilación Atrial/complicaciones , Fibrilación Atrial/cirugía , Volumen Sistólico , Función Ventricular Izquierda , Estudios Retrospectivos , Resultado del Tratamiento
9.
Artículo en Inglés | MEDLINE | ID: mdl-39402141

RESUMEN

INTRODUCTION: Numerous cartilage repair procedures have been developed for focal lesions to minimize suffering and possibly prevent the development of osteoarthritis with a focus on so-called one-step procedures. The aim of this work was to investigate the effects of both focal cartilage defects and a biomaterial (ChondroFiller) on the corresponding articular cartilage. MATERIALS AND METHODS: On a friction test stand, 18 porcine osteochondral cylinders were tested in six experimental setups under cyclic loading (33 N) against a friction partner in saline solution. The friction partner (cartilage, bone, cartilage defect, cartilage defect with ChondroFiller) and the running times (1 hour and 6 hours) were varied. The damage to the osteochondral cylinders was assessed histologically using a visual damage classification. RESULTS: The cartilage versus bone group showed severe cartilage damage in both the one-hour and six-hour experiments, with an average damage score of 3.5. Damage in the cartilage versus cartilage defect group was moderate, with damage values of 2.5 (1 h) and 2.67 (6 h). The cartilage versus cartilage defect with ChondroFiller group showed a damage value of 2.67 for the one-hour and 2.5 for the six-hour trials. CONCLUSIONS: Even focal grade IV cartilage lesions can lead to significant damage to the corresponding cartilage in vitro. The damage could not be reduced by the use of ChondroFiller, likely because of the initial instability of this biomaterial. Therefore, a biomaterial must be stable in the beginning with regard to full weight-bearing, or joint loading should be delayed until stable filling of the defect is achieved.

10.
Arch Orthop Trauma Surg ; 144(6): 2683-2689, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38693287

RESUMEN

INTRODUCTION: Arthroscopic revision anterior shoulder instability repair has been proposed, and early clinical results have been promising. However, long-term results after this procedure and the probable risk factors for failure have not been sufficiently discussed in the literature. MATERIALS AND METHODS: Thirty-eight patients who were diagnosed with recurrent anteroinferior shoulder instability after failed Bankart repair, treated with ACRR between September 1998 and November 2003 and able to be contacted were included. Of these patients, 2 were excluded from the study due to the use of SureTak anchors for fixation, and 5 other patients refused to participate in the study due to lack of interest (3 patients) or lack of time (2 patients). The remaining shoulders were clinically examined at a minimum of ten years after surgery via the ASES, Constant, AAOS, Rowe, Dawson and VAS scores for pain and stability. Degenerative arthropathy was assessed with the modified Samilson-Prieto score. RESULTS: All 31 remaining shoulders were evaluated at a mean time of 11.86 years (142.4 months) after surgery. Six patients (19.35%) reported redisolcation after the revision procedure, 4 of whom were affected by a new significant shoulder trauma. The ROWE and Constant scores improved significantly. Moderate to severe dislocation arthropathy was observed in 19.4% of patients. Five patients (16.2%) were not satisfied with the procedure. CONCLUSION: Long-term follow-up after ACRR shows predictable results, with a high degree of patient satisfaction, good to excellent patient-reported outcome scores and minimal radiological degenerative changes. However, with an average recurrence rate of 19.3% after 11.86 years, the redislocation rate appears high. With careful patient selection, recurrence rates can be significantly reduced.


Asunto(s)
Artroscopía , Inestabilidad de la Articulación , Reoperación , Articulación del Hombro , Anclas para Sutura , Humanos , Artroscopía/métodos , Inestabilidad de la Articulación/cirugía , Inestabilidad de la Articulación/etiología , Reoperación/estadística & datos numéricos , Reoperación/métodos , Adulto , Masculino , Femenino , Estudios de Seguimiento , Articulación del Hombro/cirugía , Articulación del Hombro/fisiopatología , Persona de Mediana Edad , Luxación del Hombro/cirugía , Adulto Joven , Insuficiencia del Tratamiento , Adolescente
11.
Psychother Res ; : 1-13, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38484365

RESUMEN

This study investigated if in-session reflective functioning (RF) of mothers improved between and within sessions of brief dyadic focused parent-infant psychotherapy (fPIP) for the treatment of regulatory disorders in infants.In-session RF was coded for 44 therapy sessions from N = 11 mothers randomly selected from a RCT on the efficacy of fPIP as part of secondary analyses. A new rating system distinguished self-focused and child-focused in-session RF. Cumulative ordinal regression models were applied to analyze the dynamics of in-session RF within and across sessions, controlling for word count of each statement.While in-session RF improved significantly within sessions, between-session RF improved significantly only in the second session compared to the first with a significant decrease observed in the last session. Child-focused in-session RF was significantly lower than self-focused in-session RF at the beginning of the sessions but improved significantly stronger than self-focused in-session RF during sessions.In-session RF (particularly in child-focused statements) can be regarded as a dynamic change process relevant within each session of dyadic fPIP. Improvements made on a session-by-session basis may not be maintained until the next session. Implications for practitioners and in-session RF research are discussed.

12.
Angew Chem Int Ed Engl ; 63(37): e202406551, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-38822492

RESUMEN

It has recently been shown that a bolus of hyperpolarized nuclear spins can yield stimulated emission signals similar in nature to maser signals, potentially enabling new ways of sensing hyperpolarized contrast media, including most notably [1-13C]pyruvate that is under evaluation in over 50 clinical trials for metabolic imaging of cancer. The stimulated NMR signal emissions lasting for minutes do not require radio-frequency excitation, offering unprecedented advantages compared to conventional MR sensing. However, creating nuclear spin maser emission is challenging in practice due to stringent fundamental requirements, making practical in vivo applications hardly possible using conventional passive MR detectors. Here, we demonstrate the utility of a wireless NMR maser detector, the quality factor of which was enhanced 22-fold (to 1,670) via parametric pumping. This active-feedback technique breaks the intrinsic fundamental limit of NMR detector circuit quality factor. We show the use of parametric pumping to reduce the threshold requirement for inducing nuclear spin masing at 300 MHz resonance frequency in a preclinical MRI scanner. Indeed, stimulated emission from hyperpolarized protons was obtained under highly unfavorable conditions of low magnetic field homogeneity (T2* of 3 ms). Greater gains of the quality factor of the MR detector (up to 1 million) were also demonstrated.


Asunto(s)
Espectroscopía de Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Tecnología Inalámbrica , Ácido Pirúvico/química
13.
Pflugers Arch ; 475(9): 1061-1072, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37464190

RESUMEN

Several proteins are implicated in transmembrane fatty acid transport. The purpose of this study was to quantify the variation in fatty acid oxidation rates during exercise explained by skeletal muscle proteins involved in fatty acid transport. Seventeen endurance-trained males underwent a (i) fasted, incremental cycling test to estimate peak whole-body fatty acid oxidation rate (PFO), (ii) resting vastus lateralis microbiopsy, and (iii) 2 h of fed-state, moderate-intensity cycling to estimate whole-body fatty acid oxidation during fed-state exercise (FO). Bivariate correlations and stepwise linear regression models of PFO and FO during 0-30 min (early FO) and 90-120 min (late FO) of continuous cycling were constructed using muscle data. To assess the causal role of transmembrane fatty acid transport in fatty acid oxidation rates during exercise, we measured fatty acid oxidation during in vivo exercise and ex vivo contractions in wild-type and CD36 knock-out mice. We observed a novel, positive association between vastus lateralis FATP1 and PFO and replicated work reporting a positive association between FABPpm and PFO. The stepwise linear regression model of PFO retained CD36, FATP1, FATP4, and FABPpm, explaining ~87% of the variation. Models of early and late FO explained ~61 and ~65% of the variation, respectively. FATP1 and FATP4 emerged as contributors to models of PFO and FO. Mice lacking CD36 had impaired whole-body and muscle fatty acid oxidation during exercise and muscle contractions, respectively. These data suggest that substantial variation in fatty acid oxidation rates during exercise can be explained by skeletal muscle proteins involved in fatty acid transport.


Asunto(s)
Proteínas de Transporte de Ácidos Grasos , Proteínas Musculares , Masculino , Ratones , Animales , Proteínas de Transporte de Ácidos Grasos/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Antígenos CD36/metabolismo , Ácidos Grasos/metabolismo , Oxidación-Reducción
14.
J Am Chem Soc ; 145(20): 11121-11129, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37172079

RESUMEN

Conventional nuclear magnetic resonance (NMR) enables detection of chemicals and their transformations by exciting nuclear spin ensembles with a radio-frequency pulse followed by detection of the precessing spins at their characteristic frequencies. The detected frequencies report on chemical reactions in real time and the signal amplitudes scale with concentrations of products and reactants. Here, we employ Radiofrequency Amplification by Stimulated Emission of Radiation (RASER), a quantum phenomenon producing coherent emission of 13C signals, to detect chemical transformations. The 13C signals are emitted by the negatively hyperpolarized biomolecules without external radio frequency pulses and without any background signal from other, nonhyperpolarized spins in the ensemble. Here, we studied the hydrolysis of hyperpolarized ethyl-[1-13C]acetate to hyperpolarized [1-13C]acetate, which was analyzed as a model system by conventional NMR and 13C RASER. The chemical transformation of 13C RASER-active species leads to complete and abrupt disappearance of reactant signals and delayed, abrupt reappearance of a frequency-shifted RASER signal without destroying 13C polarization. The experimentally observed "quantum" RASER threshold is supported by simulations.

15.
Am J Physiol Renal Physiol ; 325(3): F299-F316, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37410897

RESUMEN

Endothelial cells in blood vessels in the kidney exert different functions depending on the (micro)vascular bed they are located in. The present study aimed to investigate microRNA and mRNA transcription patterns that underlie these differences. We zoomed in on microvascular compartments in the mouse renal cortex by laser microdissecting the microvessels prior to small RNA- and RNA-sequencing analyses. By these means, we characterized microRNA and mRNA transcription profiles of arterioles, glomeruli, peritubular capillaries, and postcapillary venules. Quantitative RT-PCR, in situ hybridization, and immunohistochemistry were used to validate sequencing results. Unique microRNA and mRNA transcription profiles were found in all microvascular compartments, with dedicated marker microRNAs and mRNAs showing enriched transcription in a single microvascular compartment. In situ hybridization validated the localization of microRNAs mmu-miR-140-3p in arterioles, mmu-miR-322-3p in glomeruli, and mmu-miR-451a in postcapillary venules. Immunohistochemical staining showed that von Willebrand factor protein was mainly expressed in arterioles and postcapillary venules, whereas GABRB1 expression was enriched in glomeruli, and IGF1 was enriched in postcapillary venules. More than 550 compartment-specific microRNA-mRNA interaction pairs were identified that carry functional implications for microvascular behavior. In conclusion, our study identified unique microRNA and mRNA transcription patterns in microvascular compartments of the mouse kidney cortex that underlie microvascular heterogeneity. These patterns provide important molecular information for future studies into differential microvascular engagement in health and disease.NEW & NOTEWORTHY Renal endothelial cells display a high level of heterogeneity depending on the (micro)vascular bed they reside in. The molecular basis contributing to these differences is poorly understood yet of high importance to increase understanding of microvascular engagement in the kidney in health and disease. This report describes m(icro)RNA expression profiles of microvascular beds in the mouse renal cortex and uncovers microvascular compartment-specific m(icro)RNAs and miRNA-mRNA pairs, thereby revealing important molecular mechanisms underlying renal microvascular heterogeneity.


Asunto(s)
MicroARNs , Transcriptoma , Ratones , Animales , Células Endoteliales/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Riñón/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
16.
Biochem Biophys Res Commun ; 647: 37-46, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-36709671

RESUMEN

Macrophages (MΦ) are remarkably plastic cells, which assume phenotypes in every shade between a pro-inflammatory classical activation, and anti-inflammatory or resolving activation. Therefore, elucidation of mechanisms involved in shaping MΦ plasticity and function is key to understand their role during immunological balance. The immune-modulating CD83 molecule is expressed on activated immune cells and various tissue resident MΦ, rendering it an interesting candidate for affecting MΦ biology. However, in-depth analyses of the precise kinetics and trafficking of CD83 within pro-inflammatory, LPS activated bone-marrow-derived MΦ have not been performed. In this study, we show that activation with LPS leads to a very fast and strong, but transient increase of CD83 expression on these cells. Its expression peaks within 2 h of stimulation and is thereby faster than the early activation antigen CD69. To trace the CD83 trafficking through MΦs, we employed multiple inhibitors, thereby revealing a de novo synthesis and transport of the protein to the cell surface followed by lysosomal degradation, all within 6 h. Moreover, we found a similar expression kinetic and trafficking in human monocyte derived MΦ. This places CD83 at a very early point of MΦ activation suggesting an important role in decisions regarding the subsequent cellular fate.


Asunto(s)
Lipopolisacáridos , Macrófagos , Humanos , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Diferenciación Celular , Membrana Celular , Fenotipo
17.
J Magn Reson Imaging ; 57(6): 1865-1875, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36315000

RESUMEN

BACKGROUND: Three-dimensional (3D) multiecho balanced steady-state free precession (ME-bSSFP) has previously been demonstrated in preclinical hyperpolarized (HP) 13 C-MRI in vivo experiments, and it may be suitable for clinical metabolic imaging of prostate cancer (PCa). PURPOSE: To validate a signal simulation framework for the use of sequence parameter optimization. To demonstrate the feasibility of ME-bSSFP for HP 13 C-MRI in patients. To evaluate the metabolism in PCa measured by ME-bSSFP. STUDY TYPE: Retrospective single-center cohort study. PHANTOMS/POPULATION: Phantoms containing aqueous solutions of [1-13 C] lactate (2.3 M) and [13 C] urea (8 M). Eight patients (mean age 67 ± 6 years) with biopsy-confirmed Gleason 3 + 4 (n = 7) and 4 + 3 (n = 1) PCa. FIELD STRENGTH/SEQUENCES: 1 H MRI at 3 T with T2 -weighted turbo spin-echo sequence used for spatial localization and spoiled dual gradient-echo sequence used for B0 -field measurement. ME-bSSFP sequence for 13 C MR spectroscopic imaging with retrospective multipoint IDEAL metabolite separation. ASSESSMENT: The primary endpoint was the analysis of pyruvate-to-lactate conversion in PCa and healthy prostate regions of interest (ROIs) using model-free area under the curve (AUC) ratios and a one-directional kinetic model (kP ). The secondary objectives were to investigate the correlation between simulated and experimental ME-bSSFP metabolite signals for HP 13 C-MRI parameter optimization. STATISTICAL TESTS: Pearson correlation coefficients with 95% confidence intervals and paired t-tests. The level of statistical significance was set at P < 0.05. RESULTS: Strong correlations between simulated and empirical ME-bSSFP signals were found (r > 0.96). Therefore, the simulation framework was used for sequence optimization. Whole prostate metabolic HP 13 C-MRI, observing the conversion of pyruvate into lactate, with a temporal resolution of 6 seconds was demonstrated using ME-bSSFP. Both assessed metrics resulted in significant differences between PCa (mean ± SD) (AUC = 0.33 ± 012, kP  = 0.038 ± 0.014) and healthy (AUC = 0.15 ± 0.10, kP  = 0.011 ± 0.007) ROIs. DATA CONCLUSION: Metabolic HP 13 C-MRI in the prostate using ME-bSSFP allows for differentiation between aggressive PCa and healthy tissue. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.


Asunto(s)
Neoplasias de la Próstata , Ácido Pirúvico , Masculino , Humanos , Persona de Mediana Edad , Anciano , Ácido Pirúvico/química , Ácido Pirúvico/metabolismo , Estudios Retrospectivos , Estudios de Cohortes , Neoplasias de la Próstata/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Ácido Láctico
18.
Chemphyschem ; 24(2): e202200615, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36106366

RESUMEN

The metabolism of malignant cells differs significantly from that of healthy cells and thus, it is possible to perform metabolic imaging to reveal not only the exact location of a tumor, but also intratumoral areas of high metabolic activity. Herein, we demonstrate the feasibility of metabolic tumor imaging using signal-enhanced 1-13 C-pyruvate-d3 , which is rapidly enhanced via para-hydrogen, and thus, the signal is amplified by several orders of magnitudes in less than a minute. Using as a model, human melanoma xenografts injected with signal-enhanced 1-13 C-pyruvate-d3, we show that the conversion of pyruvate into lactate can be monitored along with its kinetics, which could pave the way for rapidly detecting and monitoring changes in tumor metabolism.


Asunto(s)
Neoplasias , Ácido Pirúvico , Humanos , Ácido Pirúvico/metabolismo , Hidrógeno , Imagen por Resonancia Magnética/métodos , Isótopos de Carbono
19.
J Clin Child Adolesc Psychol ; 52(6): 797-810, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35704507

RESUMEN

OBJECTIVE: Breathing exercises have been proposed as an effective intervention to improve subjective well-being and manage anxiety symptoms. As they are comparatively easy to learn and to implement, breathing exercises may be particularly beneficial for children. Although breathing exercises are ultimately supposed to provide salutary effects in individuals' everyday lives, immediate effects of breathing exercises in naturalistic contexts have received limited empirical attention. The purpose of this study was to examine immediate effects of slow-paced diaphragmatic breathing on negative affect as well as on relaxation in an ecologically valid setting. To that end, we conducted a micro-randomized trial in children's daily life. METHOD: On each of 15 days, children (N = 171, aged 9-13 years, 54% female) were randomized to different conditions: performing a video-guided slow-paced diaphragmatic breathing exercise (experimental condition), watching a different video (active control condition), or a passive control condition. RESULTS: The breathing exercise had no immediate effects on negative affect or relaxation compared to both control conditions. However, in situations when children reported higher levels of worries than usual, relaxation was higher when children performed the breathing exercise compared to the passive control condition. Compared to the active control condition, the breathing exercise did not result in higher levels of relaxation in situations when children worried more than normally. CONCLUSIONS: Findings highlight that context-specific factors can modulate the effectiveness of breathing exercises and should be taken into account to tailor interventions to individuals' needs.


Asunto(s)
Ejercicios Respiratorios , Ejercicio Físico , Humanos , Femenino , Niño , Masculino
20.
BMC Musculoskelet Disord ; 24(1): 515, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37353825

RESUMEN

BACKGROUND: The extent of fatty infiltration and rotator cuff (RC) atrophy is crucial for the clinical results after rotator cuff repair (RCR). The purpose of this study was to evaluate changes in fatty infiltration and RC atrophy after revision RCR and to correlate them with functional outcome parameters. METHODS: Patients who underwent arthroscopic revision RCR for symptomatic recurrent full-thickness tear of the supraspinatus tendon between 2008 and 2014 and were retrospectively reviewed with a minimum follow up of 2 years. Magnetic resonance imaging (MRI) was performed pre- and postoperatively to assess 1) tendon integrity after revision RCR according to Sugaya classification, (2) RC atrophy according to Thomazeau classification, and (3) fatty infiltration according to Fuchs MRI classification. Constant score (CS) and the American Shoulder and Elbow Surgeon (ASES) score were used to correlate functional outcome, tendon integrity, and muscle degeneration. RESULTS: 19 patients (17 males and 2 females) with a mean age of 57.5 years (range, 34 to 72) were included into the study at a mean follow-up of 50.3 months (range, 24 - 101). At final evaluation, 9 patients (47%) presented with intact RCR and 10 patients (53%) suffered a re-tear after revision repair. No progress of fatty infiltration was observed postoperatively in the group with intact RC, atrophy progressed in only 1 out of 9 patient (11%). Fatty infiltration progressed in 5/10 patients (50%) and RC atrophy increased in 2/10 patients (20%) within the re-tear group. CS (42.7 ± 17.7 preop, 65.2 ± 20.1 postop) and ASES (47.7 ± 17.2 preop, 75.4 ± 23.7 postop) improved significantly from pre- to postoperatively (p < 0.001). A positive correlation between fatty infiltration and RC integrity was detected (r = 0.77, p < 0.01). No correlation between clinical outcome and tendon integrity or RC atrophy was observed. CONCLUSION: Arthroscopic revision RCR leads to reliable functional outcomes even in case of a recurrent RC retear. An intact RCR maintains the preoperative state of fatty infiltration and muscle atrophy but does not lead to muscle regeneration. LEVEL OF EVIDENCE: Level IV; Therapeutic study.


Asunto(s)
Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Masculino , Femenino , Humanos , Persona de Mediana Edad , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/cirugía , Manguito de los Rotadores/patología , Estudios de Seguimiento , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Lesiones del Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/patología , Resultado del Tratamiento , Estudios Retrospectivos , Artroscopía/métodos , Atrofia Muscular/diagnóstico por imagen , Atrofia Muscular/etiología , Atrofia Muscular/cirugía , Imagen por Resonancia Magnética
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