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1.
Nature ; 595(7868): 572-577, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34044428

RESUMEN

BNT162b2, a nucleoside-modified mRNA formulated in lipid nanoparticles that encodes the SARS-CoV-2 spike glycoprotein (S) stabilized in its prefusion conformation, has demonstrated 95% efficacy in preventing COVID-191. Here we extend a previous phase-I/II trial report2 by presenting data on the immune response induced by BNT162b2 prime-boost vaccination from an additional phase-I/II trial in healthy adults (18-55 years old). BNT162b2 elicited strong antibody responses: at one week after the boost, SARS-CoV-2 serum geometric mean 50% neutralizing titres were up to 3.3-fold above those observed in samples from individuals who had recovered from COVID-19. Sera elicited by BNT162b2 neutralized 22 pseudoviruses bearing the S of different SARS-CoV-2 variants. Most participants had a strong response of IFNγ+ or IL-2+ CD8+ and CD4+ T helper type 1 cells, which was detectable throughout the full observation period of nine weeks following the boost. Using peptide-MHC multimer technology, we identified several BNT162b2-induced epitopes that were presented by frequent MHC alleles and conserved in mutant strains. One week after the boost, epitope-specific CD8+ T cells of the early-differentiated effector-memory phenotype comprised 0.02-2.92% of total circulating CD8+ T cells and were detectable (0.01-0.28%) eight weeks later. In summary, BNT162b2 elicits an adaptive humoral and poly-specific cellular immune response against epitopes that are conserved in a broad range of variants, at well-tolerated doses.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , SARS-CoV-2/inmunología , Linfocitos T/inmunología , Adolescente , Adulto , Vacuna BNT162 , Linfocitos T CD8-positivos/inmunología , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Epítopos de Linfocito T/inmunología , Femenino , Humanos , Inmunoglobulina G/inmunología , Memoria Inmunológica , Interferón gamma/inmunología , Interleucina-2/inmunología , Masculino , Persona de Mediana Edad , SARS-CoV-2/química , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Células TH1/inmunología , Adulto Joven
2.
Opt Express ; 32(9): 15710-15722, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859215

RESUMEN

We compare multiple temporal pulse characterization techniques in three different pulse duration regimes from 15 fs to sub-5 fs, as there are no available standards yet for measuring such ultrashort pulses. To accomplish this, a versatile post-compression platform was developed, where the 100 fs near infrared pulses were post-compressed to the sub-two-cycle regime in a hybrid, three-stage configuration. After each stage, the duration of the compressed pulse was measured with the d-scan, TIPTOE and SRSI techniques and the retrieved temporal intensity profiles, spectrum and spectral phases were compared. Spectral homogeneity was also measured with an imaging spectrometer to understand the input coupling conditions of the temporal measurements. Our findings suggest that the different devices give similar results in terms of temporal intensity profile, however they are extremely sensitive to alignment and to beam quality, especially in the case of the shortest pulses. We address specific steps of measurement procedures, which paves the way towards the standardization of pulse characterization in the near future.

3.
Rev Cardiovasc Med ; 25(1): 30, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39077659

RESUMEN

Background: Off-pump coronary artery bypass grafting (OPCAB) is an alternative to on-pump coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). During OPCAB, the temporary use of an intracoronary shunt and inotropic medication or catecholamines should keep the central hemodynamics constant. Nevertheless, the need for conversion to on-pump CABG often occurs unexpectedly, most likely due to circulation instability. Circulation instability can appear first in peripheral body parts; therefore, peripheral microcirculation might serve as a predictor for the upcoming conversion to on-pump CABG. We investigated the impact of coronary artery ligation and shunt insertion during OPCAB on cutaneous microcirculation (cLDP) with Laser Doppler Perfusion Technology and transcutaneous oxygen partial pressure ( tcpO 2 ). Methods: In a pig model of OPCAB, peripheral circulation was evaluated after cLDP (N = 17) and tcpO 2 (N = 6) monitoring. Systolic, diastolic, and mean arterial pressure were also observed to prove the independence of perfusion measurement results from hemodynamic parameters. Results: Ligation time during cLDP and tcpO 2 monitoring were 101 ± 49 s and 83 ± 33 s, respectively. Shunt time was 11 ± 3 min during cLDP and 13 ± 2 min during tcpO 2 measurement. Ligation of the left anterior descending coronary artery (LAD) reduced cLDP significantly to 88 ± 14% (p = 0.007) and tcpO 2 to 71 ± 25% (p = 0.038). Inserting a temporary shunt into the LAD significantly improved cLDP (p = 0.006) and tcpO 2 (p = 0.015) compared to ligation. cLDP was restored to 99%, and tcpO 2 was restored to 91% of the baseline level before ligation. All hemodynamic parameters remained stable and did not change significantly during OPCAB. Conclusions: Although hemodynamic parameters stayed constant, peripheral microcirculation was influenced markedly during OPCAB. Inserting a temporary shut into the LAD leads to a complete normalization of peripheral microcirculation, regarding evaluation by cLDP and tcpO 2 .

4.
J Natl Compr Canc Netw ; 22(6): 382-389, 2024 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-38648848

RESUMEN

BACKGROUND: Although the FDA Accelerated Approval Program (AAP) has come under scrutiny, the population-level health benefit of the program has not been quantified. Therefore, the objective of this study was to estimate the number of life years gained among patients with cancer that can be attributable to the therapies receiving FDA accelerated approvals in oncology between 2006 and 2022 in the United States. METHODS: The data sources used were FDA listings, FDA approval letters and labels, published clinical trial data and other publications including relative effectiveness estimates, and the Ipsos Oncology Uptake Tool for product uptake. Data for 130 oncology treatments approved by the FDA under the AAP were extracted and validated. We developed a decision analytic model to estimate the survival gain for each indication and to accumulate life years gained for consecutive cohorts of patients receiving the therapies. Life year gains were estimated with and without the AAP, and the incremental life years gained were attributed to the program. RESULTS: The analysis estimated that through December 2022 in the United States, the program gained approximately 263,000 life years across 69 products for which overall survival data were available, for approximately 911,000 patients with cancer. CONCLUSIONS: Policy discussions about the evaluation of AAP cannot be complete without assessing its impact on its most important target outcome: patient survival. To date, there has been no estimation of the life year gain delivered by the AAP. Our research shows that substantial number of life years were gained for patients with high unmet need by the cancer therapies approved through the program.


Asunto(s)
Aprobación de Drogas , Oncología Médica , Neoplasias , United States Food and Drug Administration , Humanos , Estados Unidos , United States Food and Drug Administration/normas , Neoplasias/tratamiento farmacológico , Neoplasias/mortalidad , Oncología Médica/normas , Oncología Médica/métodos , Antineoplásicos/uso terapéutico
5.
Cell ; 139(1): 161-74, 2009 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-19804761

RESUMEN

GABAergic interneurons are key elements in neural coding, but the mechanisms that assemble inhibitory circuits remain unclear. In the spinal cord, the transfer of sensory signals to motor neurons is filtered by GABAergic interneurons that act presynaptically to inhibit sensory transmitter release and postsynaptically to inhibit motor neuron excitability. We show here that the connectivity and synaptic differentiation of GABAergic interneurons that mediate presynaptic inhibition is directed by their sensory targets. In the absence of sensory terminals these GABAergic neurons shun other available targets, fail to undergo presynaptic differentiation, and withdraw axons from the ventral spinal cord. A sensory-specific source of brain derived neurotrophic factor induces synaptic expression of the GABA synthetic enzyme GAD65--a defining biochemical feature of this set of interneurons. The organization of a GABAergic circuit that mediates presynaptic inhibition in the mammalian CNS is therefore controlled by a stringent program of sensory recognition and signaling.


Asunto(s)
Interneuronas/fisiología , Médula Espinal/fisiología , Ácido gamma-Aminobutírico/fisiología , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Glutamato Descarboxilasa , Ratones , Neuronas Motoras/fisiología , Terminales Presinápticos , Propiocepción , Células Receptoras Sensoriales/fisiología , Médula Espinal/citología
6.
Artif Organs ; 48(1): 103-109, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37994562

RESUMEN

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is increasingly used for circulatory or pulmonary support not only in-hospital but also out-of-hospital. Small dimensions and a lightweight design are important, especially for out-of-hospital use but also for intra-hospital transportation of patients who require ECMO support. We share our first experience with the new Colibrì ECMO system. PATIENTS AND METHODS: From December 2022 to January 2023, we used the new Colibrì extracorporeal circulation (ECC) system in six patients with cardiac or pulmonary failure. RESULTS: The Colibrì system was used in-hospital in six patients with post-cardiac surgery low output syndrome, respiratory failure due to influenza or acute respiratory distress syndrome, cardiogenic shock, pulmonary embolism, and failed weaning from cardiopulmonary bypass. The system was implanted in venovenous (VV) and venoarterial (VA) fashion in 3 patients, respectively. In one patient, the configuration was switched from VA to VV after cardiac recovery. One patient received left-ventricular unloading using the IMPELLA®5.5. ECMO run time was 1 to 13 days. We did not notice any ECC system-associated complications. No ECMO system changes were required. CONCLUSION: Our case series concludes that the new Colibrì system is safe and effective for in-hospital ECMO indications. The small dimensions and lightweight design are very beneficial for the transportation of patients. It might be especially helpful for out-of-hospital situations.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Humanos , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/métodos , Choque Cardiogénico/terapia , Síndrome de Dificultad Respiratoria/terapia , Insuficiencia Respiratoria/terapia , Corazón , Estudios Retrospectivos
7.
Ultraschall Med ; 45(1): 61-68, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36781162

RESUMEN

OBJECTIVES: To test the accuracy of TVS applying the IDEA approach for suspected rectosigmoid DE and to determine the frequency of other pelvic diseases mimicking DE in patients undergoing surgery. MATERIALS UND METHODS: Prospective single center observational study including consecutive women undergoing TVS for clinically suspected rectosigmoid DE followed by conservative or surgical therapy. TVS findings were compared with those obtained by laparoscopy and confirmed histologically. RESULTS: Of the 671 included patients, 128 women opted for medical therapy, and 6 patients decided for surgery but did not give consent to participate in the study. 537 women were enrolled in the final analysis. 279 (52 %) exhibited surgically confirmed rectosigmoid DE. The sensitivity and specificity, positive and negative predictive value (PPV, NPV), positive and negative likelihood ratio (LR+/-) and accuracy of TVS for diagnosing DE in the rectosigmoid were 93.5 %, 94.6 %, 94.9 %, 93.1 %, 17.24, 0.07, 94.04 %. 12 women who were clinically suspected for DE and mimicked sonographic signs fulfilling the IDEA criteria did exhibit other pathologies. Diagnoses were as follows: vaginal Gartner duct cyst (3/291;1.0 %), anorectal abscess (3/291; 1.0 %), rectal cancer (2/291;0.7 %), hydrosalpinx (2/291;0.7 %), metastatic endometrial cancer (1/291;0.35 %) and Crohn's disease (1/291;0.35 %). CONCLUSION: TVS for diagnosing colorectal DE applying the IDEA criteria is highly accurate for presurgical diagnosis. However, additional pelvic pathologies are encountered in 4-5 % of women attending for suspected rectosigmoid DE. These need to be taken into account when investigating patients for suspected DE.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Endometriosis , Femenino , Humanos , Citarabina , Dexametasona , Endometriosis/diagnóstico por imagen , Endometriosis/cirugía , Etopósido , Ifosfamida , Estudios Prospectivos , Sensibilidad y Especificidad , Ultrasonografía/métodos , Vagina/diagnóstico por imagen
8.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38279260

RESUMEN

Donation after circulatory death (DCD) hearts are predominantly maintained by normothermic blood perfusion (NBP). Nevertheless, it was shown that hypothermic crystalloid perfusion (HCP) is superior to blood perfusion to recondition left ventricular (LV) contractility. However, transcriptomic changes in the myocardium and coronary artery in DCD hearts after HCP and NBP have not been investigated yet. In a pig model, DCD hearts were harvested and maintained for 4 h by NBP (DCD-BP group, N = 8) or HCP with oxygenated histidine-tryptophane-ketoglutarate (HTK) solution (DCD-HTK, N = 8) followed by reperfusion with fresh blood for 2 h. In the DCD group (N = 8), hearts underwent reperfusion immediately after procurement. In the control group (N = 7), no circulatory death was induced. We performed transcriptomics from LV myocardial and left anterior descending (LAD) samples using microarrays (25,470 genes). We applied the Boruta algorithm for variable selection to identify relevant genes. In the DCD-BP group, compared to DCD, six genes were regulated in the myocardium and 1915 genes were regulated in the LAD. In the DCD-HTK group, 259 genes were downregulated in the myocardium and 27 in the LAD; and 52 genes were upregulated in the myocardium and 765 in the LAD, compared to the DCD group. We identified seven genes of relevance for group identification: ITPRIP, G3BP1, ARRDC3, XPO6, NOP2, SPTSSA, and IL-6. NBP resulted in the upregulation of genes involved in mitochondrial calcium accumulation and ROS production, the reduction in microvascular endothelial sprouting, and inflammation. HCP resulted in the downregulation of genes involved in NF-κB-, STAT3-, and SASP-activation and inflammation.


Asunto(s)
Trasplante de Corazón , Porcinos , Animales , Humanos , Trasplante de Corazón/métodos , Vasos Coronarios , Transcriptoma , ADN Helicasas , Donantes de Tejidos , Proteínas de Unión a Poli-ADP-Ribosa , ARN Helicasas , Proteínas con Motivos de Reconocimiento de ARN , Miocardio , Perfusión/métodos , Perfilación de la Expresión Génica , Inflamación , Preservación de Órganos/métodos , Muerte
9.
Int J Mol Sci ; 25(4)2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38396938

RESUMEN

Protection of the coronary arteries during donor heart maintenance is pivotal to improve results and prevent the development of coronary allograft vasculopathy. The effect of hypothermic, oxygenated perfusion (HOP) with the traditional HTK and the novel HTK-N solution on the coronary microvasculature of donation-after-circulatory-death (DCD) hearts is known. However, the effect on the coronary macrovasculature is unknown. Thus, we maintained porcine DCD hearts by HOP with HTK or HTK-N for 4 h, followed by transplantation-equivalent reperfusion with blood for 2 h. Then, we removed the left anterior descending coronary artery (LAD) and compared the endothelial-dependent and -independent vasomotor function of both groups using bradykinin and sodium-nitroprusside (SNP). We also determined the transcriptome of LAD samples using microarrays. The endothelial-dependent relaxation was significantly better after HOP with HTK-N. The endothelial-independent relaxation was comparable between both groups. In total, 257 genes were expressed higher, and 668 genes were expressed lower in the HTK-N group. Upregulated genes/pathways were involved in endothelial and vascular smooth muscle cell preservation and heart development. Downregulated genes were related to ischemia/reperfusion injury, oxidative stress, mitochondrion organization, and immune reaction. The novel HTK-N solution preserves the endothelial function of DCD heart coronary arteries more effectively than traditional HTK.


Asunto(s)
Trasplante de Corazón , Porcinos , Animales , Humanos , Trasplante de Corazón/métodos , Donantes de Tejidos , Corazón , Perfusión , Vasos Coronarios/fisiología , Preservación de Órganos/métodos
10.
Circulation ; 145(13): 959-968, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35213213

RESUMEN

BACKGROUND: Cardiac surgery often represents the only treatment option in patients with infective endocarditis (IE). However, IE surgery may lead to a sudden release of inflammatory mediators, which is associated with postoperative organ dysfunction. We investigated the effect of hemoadsorption during IE surgery on postoperative organ dysfunction. METHODS: This multicenter, randomized, nonblinded, controlled trial assigned patients undergoing cardiac surgery for IE to hemoadsorption (integration of CytoSorb to cardiopulmonary bypass) or control. The primary outcome (change in sequential organ failure assessment score [ΔSOFA]) was defined as the difference between the mean total postoperative SOFA score, calculated maximally to the 9th postoperative day, and the basal SOFA score. The analysis was by modified intention to treat. A predefined intergroup comparison was performed using a linear mixed model for ΔSOFA including surgeon and baseline SOFA score as fixed effect covariates and with the surgical center as random effect. The SOFA score assesses dysfunction in 6 organ systems, each scored from 0 to 4. Higher scores indicate worsening dysfunction. Secondary outcomes were 30-day mortality, duration of mechanical ventilation, and vasopressor and renal replacement therapy. Cytokines were measured in the first 50 patients. RESULTS: Between January 17, 2018, and January 31, 2020, a total of 288 patients were randomly assigned to hemoadsorption (n=142) or control (n=146). Four patients in the hemoadsorption and 2 in the control group were excluded because they did not undergo surgery. The primary outcome, ΔSOFA, did not differ between the hemoadsorption and the control group (1.79±3.75 and 1.93±3.53, respectively; 95% CI, -1.30 to 0.83; P=0.6766). Mortality at 30 days (21% hemoadsorption versus 22% control; P=0.782), duration of mechanical ventilation, and vasopressor and renal replacement therapy did not differ between groups. Levels of interleukin-1ß and interleukin-18 at the end of integration of hemoadsorption to cardiopulmonary bypass were significantly lower in the hemoadsorption than in the control group. CONCLUSIONS: This randomized trial failed to demonstrate a reduction in postoperative organ dysfunction through intraoperative hemoadsorption in patients undergoing cardiac surgery for IE. Although hemoadsorption reduced plasma cytokines at the end of cardiopulmonary bypass, there was no difference in any of the clinically relevant outcome measures. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03266302.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Endocarditis Bacteriana , Endocarditis , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/métodos , Citocinas , Endocarditis/cirugía , Humanos , Insuficiencia Multiorgánica , Resultado del Tratamiento
11.
J Transl Med ; 21(1): 799, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37946197

RESUMEN

BACKGROUND: Heart transplantation (HTX) is the standard treatment for end-stage heart failure. However, reperfusion following an ischemic period can contribute to myocardial injury. Neutrophil infiltration, along with the subsequent release of tissue-degrading neutrophil elastase (NE)-related serine proteases and oxygen-derived radicals, is associated with adverse graft outcomes. The inhibition of cathepsin C (CatC) has been shown to block NE-related protease activation. We hypothesized that the CatC inhibitor BI-9740 improves graft function after HTX. METHODS: In a rat model of HTX, the recipient Lewis rats were orally administered with either a placebo (n = 12) or BI-9740 (n = 11, 20 mg/kg) once daily for 12 days. Donor hearts from untreated Lewis rats were explanted, preserved in a cardioplegic solution, and subsequently heterotopically implanted. In vivo left-ventricular (LV) graft function was assessed after 1 h of reperfusion. The proteolytic activity of neutrophil serine proteases was determined in bone marrow lysates from BI-9740-treated and control rats. Additionally, myocardial morphological changes were examined, and heart samples underwent immunohistochemistry and western blot analysis. RESULTS: The NE-related proteolytic activity in bone marrow cell lysates was markedly decreased in the BI-9740-treated rats compared to those of the placebo group. Histopathological lesions, elevated CatC and myeloperoxidase-positive cell infiltration, and nitrotyrosine immunoreactivity with an increased number of poly(ADP-ribose) polymerase (PARP)-1-positive cells were lowered in the hearts of animals treated with BI-9740 compared to placebo groups. Regarding the functional parameters of the implanted graft, improvements were observed in both systolic function (LV systolic pressure 110 ± 6 vs 74 ± 6 mmHg; dP/dtmax 2782 ± 149 vs 2076 ± 167 mmHg/s, LV developed pressure, at an intraventricular volume of 200 µl, p < 0.05) and diastolic function in the hearts of BI-9740 treated animals compared with those receiving the only placebo. Furthermore, the administration of BI-9740 resulted in a shorter graft re-beating time compared to the placebo group. However, this study did not provide evidence of DNA fragmentation, the generation of both superoxide anions and hydrogen peroxide, correlating with the absence of protein alterations related to apoptosis, as evidenced by western blot in grafts after HTX. CONCLUSIONS: We provided experimental evidence that pharmacological inhibition of CatC improves graft function following HTX in rats.


Asunto(s)
Proteasas de Cisteína , Trasplante de Corazón , Ratas , Animales , Humanos , Trasplante de Corazón/métodos , Catepsina C , Donantes de Tejidos , Ratas Endogámicas Lew , Corazón , Especies Reactivas de Oxígeno , Serina Proteasas
12.
Mol Ecol ; 32(24): 6924-6938, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37873915

RESUMEN

Environmental circumstances shaping soil microbial communities have been studied extensively. However, due to disparate study designs, it has been difficult to resolve whether a globally consistent set of predictors exists, or context-dependency prevails. Here, we used a network of 18 grassland sites (11 of those containing regional plant productivity gradients) to examine (i) if similar abiotic or biotic factors predict both large-scale (across sites) and regional-scale (within sites) patterns in bacterial and fungal community composition, and (ii) if microbial community composition differs consistently at two levels of regional plant productivity (low vs. high). Our results revealed that bacteria were associated with particular soil properties (such as base saturation) and both bacteria and fungi were associated with plant community composition across sites and within the majority of sites. Moreover, a discernible microbial community signal emerged, clearly distinguishing high and low-productivity soils across different grasslands independent of their location in the world. Hence, regional productivity differences may be typified by characteristic soil microbial communities across the grassland biome. These results could encourage future research aiming to predict the general effects of global changes on soil microbial community composition in grasslands and to discriminate fertile from infertile systems using generally applicable microbial indicators.


Asunto(s)
Pradera , Microbiota , Microbiología del Suelo , Microbiota/genética , Hongos/genética , Bacterias/genética , Plantas/microbiología , Suelo
13.
Opt Express ; 31(26): 44160-44176, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38178494

RESUMEN

Performance of the novel high repetition rate HF-PW laser system of ELI ALPS is presented in its first operation phase at 400 TW and 700 TW levels. Long-term operation was tested at 2.5 and 10 Hz repetition rates, where an exceptional 0.66% and 1.08% shot-to-shot energy stability was demonstrated, respectively. Thorough spatio-spectral and temporal measurements confirmed high quality output pulses with a Strehl ratio of >0.9 after compression at both repetition rates. Amplified pulses with an unprecedentedly high 240 W average power were reached for the first time from a PW-class amplifier chain by using novel pseudo-active mirror disk amplification-based pump lasers.

14.
Rev Cardiovasc Med ; 24(1): 6, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39076867

RESUMEN

Background: Geometrical alterations in the coronary resistance artery network and the potential involvement of Tenascin C (TNC) extracellular matrix protein were investigated in diabetic and control mice. Methods: Diabetes was induced by streptozotocin (STZ) injections (n = 7-11 animals in each group) in Tenascin C KO (TNC KO) mice and their Wild type (A/J) littermates. After 16-18 weeks the heart was removed and the whole subsurface network of the left coronary artery was prepared (down to branches of 40 µ m outer diameter), in situ pressure-perfused and studied using video-microscopy. Outer and inner diameters, wall thicknesses and bifurcation angles were measured on whole network pictures reconstructed into collages at 1.7 µ m pixel resolutions. Results: Diabetes induced abnormal morphological alterations including trifurcations, sharp bends of larger branches, and branches directed retrogradely (p < 0.001 by the χ 2 test). Networks of TNC KO mice tended to form early divisions producing parallelly running larger branches (p < 0.001 by the χ 2 probe). Networks of coronary resistance arteries were substantially more abundant in 100-180 µ m components, appearing in 2-5 mm flow distance from orifice in diabetes. This was accompanied by thickening of the wall of larger arterioles ( > 220 µ m) and thinning of the wall of smaller (100-140 µ m) arterioles (p < 0.001). Blood flow should cover larger distances in diabetic networks, but interestingly STZ-induced diabetes did not generate further geometrical changes in TNC KO mice. Conclusions: Diabetes promotes hypertrophic and hypotrophic vascular remodeling and induces vasculogenesis at well defined, specific positions of the coronary vasculature. TNC plays a pivotal role in the formation of coronary network geometry, and TNC deletion causes parallel fragmentation preventing diabetes-induced abnormal vascular morphologies.

15.
Respir Res ; 24(1): 174, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37386635

RESUMEN

BACKGROUND: C-type natriuretic peptide (CNP) is an endothelium-derived paracrine molecule with an important role in vascular homeostasis. In septic patients, the serum level of the amino-terminal propeptide of CNP (NT-proCNP) shows a strong positive correlation with inflammatory biomarkers and, if elevated, correlates with disease severity and indicates a poor outcome. It is not yet known whether NT-proCNP also correlates with the clinical outcome of patients suffering from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In the current study, we aimed to determine possible changes in the NT-proCNP levels of patients with coronavirus disease 2019 (COVID-19), with special regard to disease severity and outcome. METHODS: In this retrospective analysis, we determined the serum level of NT-proCNP in hospitalized patients with symptoms of upper respiratory tract infection, using their blood samples taken on admission, stored in a biobank. The NT-proCNP levels of 32 SARS-CoV-2 positive and 35 SARS-CoV-2 negative patients were measured to investigate possible correlation with disease outcome. SARS-CoV-2 positive patients were then divided into two groups based on their need for intensive care unit treatment (severe and mild COVID-19). RESULTS: The NT-proCNP was significantly different in the study groups (e.g. severe and mild COVID-19 and non-COVID-19 patients), but showed inverse changes compared to previous observations in septic patients: lowest levels were detected in critically ill COVID-19 patients, while highest levels in the non-COVID-19 group. A low level of NT-proCNP on admission was significantly associated with severe disease outcome. CONCLUSIONS: Low-level NT-proCNP on hospital admission is associated with a severe COVID-19 disease course. The pathomechanism underlying this observation remains to be elucidated, while future studies in larger patient cohorts are necessary to confirm these observations and reveal therapeutic importance. Trial registration DRKS00026655 Registered 26. November 2021.


Asunto(s)
COVID-19 , Sepsis , Humanos , SARS-CoV-2 , Estudios Retrospectivos , Gravedad del Paciente
16.
J Surg Res ; 283: 953-964, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36915024

RESUMEN

INTRODUCTION: Endothelial dysfunction is a potential side effect of brain death (BD). Ischemia/reperfusion (IR) injury during heart transplantation may lead to further endothelial damage. Protective effects of alpha-1-antitrypsin (AAT), a human neutrophil serine protease inhibitor, have been demonstrated against IR injury. We hypothesized that AAT protects brain-dead rats' vascular grafts from IR injury. METHODS: Donor rats were subjected to BD by inflation of a subdural balloon. After 5.5 h, aortic rings were immediately mounted in organ baths (BD, n = 6 rats) or preserved in saline, supplemented either with vehicle (BD-IR, n = 8 rats) or AAT (BD-IR + AAT, n = 14 rats) for 24 h. During organ bath experiment, rings from both IR groups were exposed to hypochlorite to simulate warm reperfusion-associated endothelial injury. Endothelial function was measured ex vivo. Immunohistochemical staining for caspases was carried out and DNA-strand breaks were evaluated using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. Data are presented as median (interquartile range). RESULTS: AAT improved IR-induced decreased maximum endothelium-dependent vasorelaxation to acetylcholine in the BD-IR + AAT aortas compared to the BD-IR group (BD: 83 (9-28) % versus BD-IR: 49 (39-60) % versus BD-IR + AAT: 64 (24-42) %, P < 0.05). Additionally, an increase in the rings' sensitivity to acetylcholine was noted after AAT (pD2-value: BD-IR + AAT: 7.35 (7.06-7.89) versus BD-IR: 6.96 (6.65-7.21), P < 0.05). Caspase-3, -8, -9, and -12 immunoreactivity and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells were significantly decreased by AAT. CONCLUSIONS: AAT alleviates endothelial dysfunction, prevents increased caspase-3, -8, -9, and -12 levels, and decreases apoptotic DNA breakage due to BD and IR injury. This suggests that AAT treatment may be therapeutically beneficial to reduce IR-induced vascular damage.


Asunto(s)
Muerte Encefálica , Daño por Reperfusión , alfa 1-Antitripsina , Animales , Humanos , Ratas , Encéfalo , Caspasa 3 , ADN Nucleotidilexotransferasa , Isquemia , Daño por Reperfusión/etiología , Daño por Reperfusión/prevención & control , alfa 1-Antitripsina/farmacología
17.
J Phys Chem A ; 127(1): 99-106, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36375093

RESUMEN

Transient chemistry of sensitizing dyes is important to obtain insights into the photochemical conversion processes of light harvesting assemblies. We have now employed transient absorption spectroscopy (pulsed laser and pulse radiolysis) to characterize the excited state and radical intermediates of a perylene derivative, (5,10,15,20-Tetraphenylbisbenz[5,6]indeno[1,2,3-cd:1',2',3'-lm]perylene (DBP). The distinguishable transient absorption features for the singlet and triplet excited states and radical anion and radical cation provide spectral fingerprints to identify the reaction intermediates in photochemical energy and electron transfer processes of composite systems involving DBP. For example, identifying these transients in the energy transfer processes of the rubrene-DBP system would aid in establishing their role as annihilator-emitter for triplet-triplet annihilation up-conversion (TTA-UC). The transient characterization thus serves as an important mechanistic fingerprint for elucidating mechanistic details of systems employing DBP in optoelectronic applications.

18.
Mol Ther ; 30(5): 1850-1868, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35189345

RESUMEN

Since the first successful application of messenger ribonucleic acid (mRNA) as a vaccine agent in a preclinical study nearly 30 years ago, numerous advances have been made in the field of mRNA therapeutic technologies. This research uncovered the unique favorable characteristics of mRNA vaccines, including their ability to give rise to non-toxic, potent immune responses and the potential to design and upscale them rapidly, making them excellent vaccine candidates during the coronavirus disease 2019 (COVID-19) pandemic. Indeed, the first two vaccines against COVID-19 to receive accelerated regulatory authorization were nucleoside-modified mRNA vaccines, which showed more than 90% protective efficacy against symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection alongside tolerable safety profiles in the pivotal phase III clinical trials. Real-world evidence following the deployment of global vaccination campaigns utilizing mRNA vaccines has bolstered clinical trial evidence and further illustrated that this technology can be used safely and effectively to combat COVID-19. This unprecedented success also emphasized the broader potential of this new drug class, not only for other infectious diseases, but also for other indications, such as cancer and inherited diseases. This review presents a brief history and the current status of development of four mRNA vaccine platforms, nucleoside-modified and unmodified mRNA, circular RNA, and self-amplifying RNA, as well as an overview of the recent progress and status of COVID-19 mRNA vaccines. We also discuss the current and anticipated challenges of these technologies, which may be important for future research endeavors and clinical applications.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , COVID-19/prevención & control , Vacunas contra la COVID-19/genética , Humanos , Nucleósidos , ARN Mensajero/genética , SARS-CoV-2/genética , Vacunas Sintéticas , Vacunas de ARNm
19.
Int J Mol Sci ; 24(14)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37511486

RESUMEN

Ischemia/reperfusion (I/R)-induced endothelial dysfunction occurs in various cardiovascular disorders. I/R injury is partially driven by the release of cytokines. Known for its use in senotherapy, the JAK inhibitor ruxolitinib is able to block the release of cytokines. We investigated the effect of ruxolitinib on the cytokine release and endothelial-dependent vasorelaxation in an in vitro model of I/R. Aortic segments of C57BL/6J mice (N = 12/group) were divided into three groups: control, in vitro I/R (I/R group), and in vitro I/R with ruxolitinib during ischemic incubation (I/R+Ruxo group). We determined cytokine expression. In organ bath chambers, we investigated the maximal endothelial-dependent relaxation to acetylcholine (RmaxACh) and maximal endothelial-independent relaxation to sodium-nitroprusside (RmaxSNP). RmaxACh was decreased in I/R compared to the control (83.6 ± 2.4 vs. 48.6 ± 3.4%; p < 0.05) and I/R+Ruxo (74.4 ± 2.6 vs. 48.6 ± 3.4%; p < 0.05). RmaxSNP was comparable between all groups. IL-10 was detectable only in I/R+Ruxo. CXCL5, CCL2, CCL3, CCL8, CCL11, ICAM-1, IL-1α, IL-7, TNF-α, and G-CSF were decreased or not detectable in I/R+Ruxo. In I/R+Ruxo, ICAM-1 was reduced in rings only from male mice. Treatment of the aorta from mice during in vitro ischemia with the senomorphic agent ruxolitinib reduces cytokine release and protects the endothelium from I/R-mediated dysfunction.


Asunto(s)
Molécula 1 de Adhesión Intercelular , Daño por Reperfusión , Femenino , Ratones , Masculino , Animales , Senoterapéuticos , Ratones Endogámicos C57BL , Daño por Reperfusión/tratamiento farmacológico , Endotelio , Vasodilatación , Acetilcolina/farmacología , Citocinas/farmacología , Endotelio Vascular
20.
Int J Mol Sci ; 24(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37569709

RESUMEN

The human P-glycoprotein (P-gp), a transporter responsible for multidrug resistance, is present in the plasma membrane's raft and non-raft domains. One specific conformation of P-gp that binds to the monoclonal antibody UIC2 is primarily associated with raft domains and displays heightened internalization in cells overexpressing P-gp, such as in NIH-3T3 MDR1 cells. Our primary objective was to investigate whether the trafficking of this particular P-gp conformer is dependent on cholesterol levels. Surprisingly, depleting cholesterol using cyclodextrin resulted in an unexpected increase in the proportion of raft-associated P-gp within the cell membrane, as determined by UIC2-reactive P-gp. This increase appears to be a compensatory response to cholesterol loss from the plasma membrane, whereby cholesterol-rich raft micro-domains are delivered to the cell surface through an augmented exocytosis process. Furthermore, this exocytotic event is found to be part of a complex trafficking mechanism involving lysosomal exocytosis, which contributes to membrane repair after cholesterol reduction induced by cyclodextrin treatment. Notably, cells overexpressing P-gp demonstrated higher total cellular cholesterol levels, an increased abundance of stable lysosomes, and more effective membrane repair following cholesterol modifications. These modifications encompassed exocytotic events that involved the transport of P-gp-carrying rafts. Importantly, the enhanced membrane repair capability resulted in a durable phenotype for MDR1 expressing cells, as evidenced by significantly improved viabilities of multidrug-resistant Pgp-overexpressing immortal NIH-3T3 MDR1 and MDCK-MDR1 cells compared to their parents when subjected to cholesterol alterations.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Ciclodextrinas , Humanos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Membrana Celular/metabolismo , Ciclodextrinas/farmacología , Colesterol/metabolismo , Microdominios de Membrana/metabolismo
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