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1.
Nature ; 557(7704): 233-237, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29720661

RESUMEN

Over 60 years ago, stone tools and remains of megafauna were discovered on the Southeast Asian islands of Flores, Sulawesi and Luzon, and a Middle Pleistocene colonization by Homo erectus was initially proposed to have occurred on these islands1-4. However, until the discovery of Homo floresiensis in 2003, claims of the presence of archaic hominins on Wallacean islands were hypothetical owing to the absence of in situ fossils and/or stone artefacts that were excavated from well-documented stratigraphic contexts, or because secure numerical dating methods of these sites were lacking. As a consequence, these claims were generally treated with scepticism 5 . Here we describe the results of recent excavations at Kalinga in the Cagayan Valley of northern Luzon in the Philippines that have yielded 57 stone tools associated with an almost-complete disarticulated skeleton of Rhinoceros philippinensis, which shows clear signs of butchery, together with other fossil fauna remains attributed to stegodon, Philippine brown deer, freshwater turtle and monitor lizard. All finds originate from a clay-rich bone bed that was dated to between 777 and 631 thousand years ago using electron-spin resonance methods that were applied to tooth enamel and fluvial quartz. This evidence pushes back the proven period of colonization 6 of the Philippines by hundreds of thousands of years, and furthermore suggests that early overseas dispersal in Island South East Asia by premodern hominins took place several times during the Early and Middle Pleistocene stages1-4. The Philippines therefore may have had a central role in southward movements into Wallacea, not only of Pleistocene megafauna 7 , but also of archaic hominins.


Asunto(s)
Fósiles , Hominidae , Comportamiento del Uso de la Herramienta , Silicatos de Aluminio , Migración Animal , Animales , Arcilla , Espectroscopía de Resonancia por Spin del Electrón , Sedimentos Geológicos , Historia Antigua , Filipinas , Datación Radiométrica
2.
Lasers Med Sci ; 39(1): 122, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38703271

RESUMEN

Pulsed dye lasers are used effectively in the treatment of psoriasis with long remission time and limited side effects. It is, however, not completely understood which biological processes underlie its favorable outcome. Pulsed dye laser treatment at 585-595 nm targets hemoglobin in the blood, inducing local hyperthermia in surrounding blood vessels and adjacent tissues. While the impact of destructive temperatures on blood vessels has been well studied, the effects of lower temperatures on the function of several cell types within the blood vessel wall and its periphery are not known. The aim of our study is to assess the functionality of isolated blood vessels after exposure to moderate hyperthermia (45 to 60°C) by evaluating the function of endothelial cells, smooth muscle cells, and vascular nerves. We measured blood vessel functionality of rat mesenteric arteries (n=19) by measuring vascular contraction and relaxation before and after heating vessels in a wire myograph. To this end, we elicited vascular contraction by addition of either high potassium solution or the thromboxane analogue U46619 to stimulate smooth muscle cells, and electrical field stimulation (EFS) to stimulate nerves. For measurement of endothelium-dependent relaxation, we used methacholine. Each vessel was exposed to one temperature in the range of 45-60°C for 30 seconds and a relative change in functional response after hyperthermia was determined by comparison with the response per stimulus before heating. Non-linear regression was used to fit our dataset to obtain the temperature needed to reduce blood vessel function by 50% (Half maximal effective temperature, ET50). Our findings demonstrate a substantial decrease in relative functional response for all three cell types following exposure to 55°C-60°C. There was no significant difference between the ET50 values of the different cell types, which was between 55.9°C and 56.9°C (P>0.05). Our data show that blood vessel functionality decreases significantly when exposed to temperatures between 55°C-60°C for 30 seconds. The results show functionality of endothelial cells, smooth muscle cells, and vascular nerves is similarly impaired. These results help to understand the biological effects of hyperthermia and may aid in tailoring laser and light strategies for selective photothermolysis that contribute to disease modification of psoriasis after pulsed dye laser treatment.


Asunto(s)
Láseres de Colorantes , Animales , Ratas , Masculino , Láseres de Colorantes/uso terapéutico , Miocitos del Músculo Liso/fisiología , Miocitos del Músculo Liso/efectos de la radiación , Vasodilatación/efectos de la radiación , Vasodilatación/fisiología , Temperatura , Músculo Liso Vascular/efectos de la radiación , Músculo Liso Vascular/fisiología , Células Endoteliales/efectos de la radiación , Células Endoteliales/fisiología , Vasoconstricción/efectos de la radiación , Vasoconstricción/fisiología , Endotelio Vascular/efectos de la radiación , Ratas Wistar
3.
J Clin Monit Comput ; 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39031233

RESUMEN

Post-induction hypotension (MAP < 65 mmHg) occurs frequently and is usually caused by the cardiovascular adverse effects of the anaesthetic induction drugs used. We hypothesize that a clinically significant difference in the incidence and severity of hypotension will be found when different doses of propofol and remifentanil are used for induction of anaesthesia. METHODS: This is a secondary analysis of a randomised controlled trial wherein four groups (A-D) of patients received one out of four different combinations of propofol and remifentanil, titrated to a predicted equipotency in probability of tolerance to laryngoscopy (PTOL) according to the Bouillon interaction model. In group A, a high dose of propofol and a low dose of remifentanil was administered, and across the groups this ratio was gradually changed until it was reversed in group D. Mean and systolic arterial blood pressure (MAP, SAP) were compared at four time points (Tbaseline, Tpost-bolus, T3min, Tnadir) within and between groups Heart rate, bispectral index (BIS) and the incidence of hypotension were compared. RESULTS: Data from 76 patients was used. At Tpost-bolus a statistically significant lower MAP and SAP was found in group A versus D (p = 0.011 and p = 0.002). A significant higher heart rate was found at T3min and Tnadir between groups A and B when compared to groups C and D (p = < 0.001 and p = 0.002). A significant difference in BIS value was found over all groups at T3min and Tnadir (both p < 0.001). All other outcomes did not differ significantly between groups. CONCLUSION: Induction of anaesthesia with different predicted equipotent combinations of propofol and remifentanil did result in statistically different but clinically irrelevant differences in haemodynamic endpoints during induction of anaesthesia. Our study could not identify preferable drug combinations that decrease the risk for hypotension after induction, although they all yield a similar predicted PTOL.

4.
Eur Eat Disord Rev ; 32(5): 963-979, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38762887

RESUMEN

OBJECTIVE: Although a significant number of professionals who provide eating disorder (ED) treatment have lived experience with an ED in the past, there is no consensus on whether these professionals should use these experiences in treatment. This review aims to evaluate current literature on recovered professionals with an ED past treating ED patients, unravelling advantages and disadvantages in treatment, the impact on professionals and their surroundings, and implications for practice. METHOD: A systematic literature search was conducted which included 10 articles. We analysed qualitative data through a systematic synthesis. Strength of evidence was calculated for each subtheme. RESULTS: Three themes and 14 subthemes were divided into categories. The category 'treatment (patient-professional interaction)' was divided into: advantages, disadvantages and other implications for treatment. Additionally, the category 'professionals themselves' included subthemes that directly impact or relate to ED professionals: recovery as a non-linear process, the significant role of self-care and adverse feelings of professionals. Finally, the category 'work settings' included: company culture and training, supervision and professional development. DISCUSSION: Recovered ED professionals are a promising addition to ED treatment due to the enhanced expertise of the professional. However, attention should be paid to the risk of distorted boundaries between patient and professional.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos , Relaciones Profesional-Paciente , Humanos , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Personal de Salud/psicología
5.
Nature ; 548(7667): 322-325, 2017 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-28792933

RESUMEN

Genetic evidence for anatomically modern humans (AMH) out of Africa before 75 thousand years ago (ka) and in island southeast Asia (ISEA) before 60 ka (93-61 ka) predates accepted archaeological records of occupation in the region. Claims that AMH arrived in ISEA before 60 ka (ref. 4) have been supported only by equivocal or non-skeletal evidence. AMH evidence from this period is rare and lacks robust chronologies owing to a lack of direct dating applications, poor preservation and/or excavation strategies and questionable taxonomic identifications. Lida Ajer is a Sumatran Pleistocene cave with a rich rainforest fauna associated with fossil human teeth. The importance of the site is unclear owing to unsupported taxonomic identification of these fossils and uncertainties regarding the age of the deposit, therefore it is rarely considered in models of human dispersal. Here we reinvestigate Lida Ajer to identify the teeth confidently and establish a robust chronology using an integrated dating approach. Using enamel-dentine junction morphology, enamel thickness and comparative morphology, we show that the teeth are unequivocally AMH. Luminescence and uranium-series techniques applied to bone-bearing sediments and speleothems, and coupled uranium-series and electron spin resonance dating of mammalian teeth, place modern humans in Sumatra between 73 and 63 ka. This age is consistent with biostratigraphic estimations, palaeoclimate and sea-level reconstructions, and genetic evidence for a pre-60 ka arrival of AMH into ISEA. Lida Ajer represents, to our knowledge, the earliest evidence of rainforest occupation by AMH, and underscores the importance of reassessing the timing and environmental context of the dispersal of modern humans out of Africa.


Asunto(s)
Cuevas , Fósiles , Migración Humana/historia , Espectroscopía de Resonancia por Spin del Electrón , Historia Antigua , Humanos , Indonesia , Luminiscencia , Bosque Lluvioso , Diente/anatomía & histología , Uranio
6.
Neth Heart J ; 31(12): 500-505, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36480146

RESUMEN

OBJECTIVES: Transcatheter aortic valve replacement (TAVR) has been expanding rapidly with numerous transcatheter heart valve (THV) systems currently available. The Myval balloon-expandable (BE) valve (Meril Life Sciences Pvt. Ltd., India) is a novel THV system indicated for the treatment of patients with severe aortic stenosis. The primary objective of this study is to assess the safety and performance of the Myval BE valve. METHODS: In this prospective single-centre study, 120 consecutive patients who underwent TAVR with the Myval BE valve were included. Clinical outcomes were evaluated at 30 days and 6 months using Valve Academic Research Consortium­2 criteria. All-cause mortality, stroke, acute kidney injury, major vascular complications, moderate or severe paravalvular leakage (PVL) and need for a permanent pacemaker implantation (PPI) were investigated. RESULTS: At 6­month follow-up, all-cause death and cardiac death were seen in 5.8% and 0.8% of the patients respectively. Periprocedural stroke and need for PPI were both seen in 3.3% of the patients. Access-site-related vascular and bleeding complications were absent. Improved valve haemodynamics and no moderate to severe PVL could be seen at 30 days. An intermediate valve size was selected in 51% of the patients. CONCLUSIONS: The Myval BE valve demonstrates improved valve haemodynamics, absence of moderate to severe PVL and good safety outcomes at 6­month follow-up with low cardiac death rate and acceptable rates of permanent pacemaker implantation and periprocedural stroke. Future randomised controlled trials will further establish the clinical utility of the Myval BE valve.

7.
J Clin Monit Comput ; 36(4): 933-946, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34982349

RESUMEN

In the perioperative phase oxygen delivery and consumption can be influenced by different factors, i.e. type of surgery, anesthetic and cardiovascular drugs, or fluids. By combining near-infrared spectroscopy (NIRS) monitoring of regional tissue oxygen saturation (StO2) with an ischemic provocation test, the vascular occlusion test (VOT), local tissue oxygen consumption and vascular reactivity at the microcirculatory level can be assessed. This systematic review aims to give an overview of the clinical information that VOT-derived NIRS values can provide in the perioperative period. After performing a systematic literature search, we included 29 articles. It was not possible to perform a meta-analysis because of the lack of comparable data and the observational nature of the majority of the included articles. We have clustered the found articles in two groups: non-cardiac surgery and cardiac surgery. We found that VOT-derived NIRS values show a wide variability and are influenced by the effects of anesthetics, cardiovascular drugs, fluids, and by the type of surgery. Additionally, deviations in VOT-derived NIRS values are also associated with adverse patients' outcomes, such as postoperative complications, prolonged mechanical ventilation and prolonged hospital length of stay. However, given the variability in VOT-derived NIRS values, clinical applicability remains elusive. Future clinical interventional trials might provide additional insight into the potential of VOT associated with NIRS to optimize perioperative care by targeting specific interventions to optimize the function of the microvasculature.


Asunto(s)
Fármacos Cardiovasculares , Enfermedades Vasculares , Humanos , Microcirculación , Oxígeno , Consumo de Oxígeno , Atención Perioperativa , Espectroscopía Infrarroja Corta/métodos
8.
Clin Radiol ; 76(5): 394.e1-394.e8, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33648759

RESUMEN

AIM: To determine whether there are differences between idiopathic and hereditary haemorrhagic telangiectasia (HHT) associated pulmonary arteriovenous malformations (PAVMs) (HHT-PAVM) regarding clinical and radiographic characteristics, and the results of embolotherapy. MATERIALS AND METHODS: A retrospective analysis was undertaken of all adult and adolescent patients who were diagnosed with a PAVM on chest computed tomography (CT) from January 2006 until August 2019. RESULTS: In total, 41 patients with idiopathic PAVMs and 194 patients with genetically confirmed HHT and PAVMs were included. Idiopathic PAVMs were more frequently observed in female patients, were more solitary, and predominantly located in the lower lobes. The diameter of the feeding artery and type of PAVM (simple versus complex) were similar. Embolotherapy results were comparable between both groups with similar re-embolisation rates. CONCLUSIONS: PAVMs of idiopathic origin are predominantly found in women, more frequently located in the lower lobes, and solitary compared to HHT-PAVMs; however, the outcome of treatment is the same, suggesting that treatment and follow-up should be similar in both groups.


Asunto(s)
Fístula Arteriovenosa/complicaciones , Fístula Arteriovenosa/diagnóstico por imagen , Arteria Pulmonar/anomalías , Venas Pulmonares/anomalías , Telangiectasia Hemorrágica Hereditaria/complicaciones , Telangiectasia Hemorrágica Hereditaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Embolización Terapéutica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen , Venas Pulmonares/diagnóstico por imagen , Estudios Retrospectivos , Telangiectasia Hemorrágica Hereditaria/terapia , Telangiectasia/complicaciones , Telangiectasia/diagnóstico por imagen , Adulto Joven
9.
J Clin Monit Comput ; 35(5): 1193-1202, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-32920700

RESUMEN

Perioperative goal-directed therapy is considered to improve patient outcomes after high-risk surgery. The association of compliance with perioperative goal-directed therapy protocols and postoperative outcomes is unclear. The purpose of this study is to determine the effect of protocol compliance on postoperative outcomes following high-risk surgery, after implementation of a perioperative goal-directed therapy protocol. Through a before-after study design, patients undergoing elective high-risk surgery before (before-group) and after implementation of a perioperative goal-directed therapy protocol (after-group) were included. Perioperative goal-directed therapy in the after-group consisted of optimized stroke volume variation or stroke volume index and optimized cardiac index. Additionally, the association of protocol compliance with postoperative complications when using perioperative goal-directed therapy was assessed. High protocol compliance was defined as ≥ 85% of the procedure time spent within the individual targets. The difference in complications during the first 30 postoperative days before and after implementation of the protocol was assessed. In the before-group, 214 patients were included and 193 patients in the after-group. The number of complications was higher in the before-group compared to the after-group (n = 414 vs. 282; p = 0.031). In the after-group, patients with high protocol compliance for stroke volume variation or stroke volume index had less complications compared to patients with low protocol compliance for stroke volume variation or stroke volume index (n = 187 vs. 90; p = 0.01). Protocol compliance by the attending clinicians is essential and should be monitored to facilitate an improvement in postoperative outcomes desired by the implementation of perioperative goal-directed therapy protocols.


Asunto(s)
Fluidoterapia , Objetivos , Estudios Controlados Antes y Después , Procedimientos Quirúrgicos Electivos , Humanos , Complicaciones Posoperatorias/prevención & control
10.
Ergonomics ; 64(10): 1322-1332, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33829959

RESUMEN

This study proposes a risk analysis approach for complex healthcare processes that combines qualitative and quantitative methods to improve patient safety. We combine Healthcare Failure Mode and Effect Analysis with Computer Simulation (HFMEA-CS), to overcome widely recognised HFMEA drawbacks regarding the reproducibility and validity of the outcomes due to human interpretation, and show the application of this methodology in a complex healthcare setting. HFMEA-CS is applied to analyse drug adherence performance in the surgical admission to discharge process of pheochromocytoma patients. The multidisciplinary team identified and scored the failure modes, and the simulation model supported in prioritisation of failure modes, uncovered dependencies between failure modes, and predicted the impact of measures on system behaviour. The results show that drug adherence, defined as the percentage of required drugs received at the right time, can be significantly improved with 12%, to reach a drug adherence of 99%. We conclude that HFMEA-CS is both a viable and effective risk analysis approach, combining strengths of expert opinion and quantitative analysis, for analysing human-system interactions in socio-technical systems. Practitioner summary: We propose combining Healthcare Failure Mode and Effects Analysis with Computer Simulation (HFMEA-CS) for prospective risk analysis of complex and potentially harmful processes, to prevent critical incidents from occurring. HFMEA-CS combines expert opinions with quantitative analyses, such that the results are more reliable, reproducible, and fitting for complex healthcare settings.


Asunto(s)
Análisis de Modo y Efecto de Fallas en la Atención de la Salud , Simulación por Computador , Atención a la Salud , Humanos , Estudios Prospectivos , Reproducibilidad de los Resultados
11.
J Clin Monit Comput ; 34(3): 389-395, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32277310

RESUMEN

Tissue perfusion monitoring is increasingly being employed clinically in a non-invasive fashion. In this end-of-year summary of the Journal of Clinical Monitoring and Computing, we take a closer look at the papers published recently on this subject in the journal. Most of these papers focus on monitoring cerebral perfusion (and associated hemodynamics), using either transcranial doppler measurements or near-infrared spectroscopy. Given the importance of cerebral autoregulation in the analyses performed in most of the studies discussed here, this end-of-year summary also includes a short description of cerebral hemodynamic physiology and its autoregulation. Finally, we review articles on somatic tissue oxygenation and its possible association with outcome.


Asunto(s)
Encéfalo/fisiología , Oxígeno/química , Espectroscopía Infrarroja Corta/métodos , Ultrasonografía Doppler/métodos , Animales , Velocidad del Flujo Sanguíneo/fisiología , Lesiones Encefálicas/fisiopatología , Circulación Cerebrovascular/fisiología , Hemodinámica , Homeostasis/fisiología , Humanos , Oximetría/métodos , Consumo de Oxígeno/fisiología , Perfusión , Sevoflurano/química , Hemorragia Subaracnoidea/metabolismo
12.
Neth Heart J ; 28(5): 249-252, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32152782

RESUMEN

Aortic valve stenosis is one of the most common valvular abnormalities, which can manifest as angina, syncope, dyspnoea and sudden cardiac death. Transcatheter aortic valve implantation (TAVI) has been introduced as an alternative to surgical valve replacement in patients with severe aortic valve stenosis, resulting in less morbidity, shorter time to recovery and similar mortality rates. Progress in this field has reduced complication rates. However, the incidence of peri-procedural stroke remains relatively high (around 4%). To fully utilise the potential of TAVI, cerebral embolic protection devices (CEPD) have been developed and introduced. In this position paper, we aim to summarise the available data on several CEPD.

13.
Neth Heart J ; 28(7-8): 410-417, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32643071

RESUMEN

BACKGROUND: Previous studies have reported on myocardial injury in patients with coronavirus infectious disease 19 (COVID-19) defined as elevated cardiac biomarkers. Whether elevated biomarkers truly represent myocardial dysfunction is not known. The aim of this study was to explore the incidence of ventricular dysfunction and assess its relationship with biomarker analyses. METHODS: This cross-sectional study ran from April 1 to May 12, 2020, and consisted of all consecutively admitted patients to the Radboud university medical centre nursing ward for COVID-19. Laboratory assessment included high-sensitivity Troponin T and N­terminal pro-B-type natriuretic peptide (NT-proBNP). Echocardiographic evaluation focused on left and right ventricular systolic function and global longitudinal strain (GLS). RESULTS: In total, 51 patients were included, with a median age of 63 years (range 51-68 years) of whom 80% was male. Troponin T was elevated (>14 ng/l) in 47%, and a clinically relevant Troponin T elevation (10â€¯× URL) was found in three patients (6%). NT-proBNP was elevated (>300 pg/ml) in 24 patients (47%), and in four (8%) the NT-proBNP concentration was >1,000 pg/ml. Left ventricular dysfunction (ejection fraction <52% and/or GLS >-18%) was observed in 27%, while right ventricular dysfunction (TAPSE <17 mm and/or RV S' < 10 cm/s) was seen in 10%. There was no association between elevated Troponin T or NT-proBNP and left or right ventricular dysfunction. Patients with confirmed pulmonary embolism had normal right ventricular function. CONCLUSIONS: In hospitalised patients, it seems that COVID-19 predominantly affects the respiratory system, while cardiac dysfunction occurs less often. Based on a single echocardiographic evaluation, we found no relation between elevated Troponin T or NT-proBNP, and ventricular dysfunction. Echocardiography has limited value in screening for ventricular dysfunction.

14.
Appl Microbiol Biotechnol ; 103(9): 3597-3614, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30810776

RESUMEN

This review covers the current knowledge of the cytochrome P450 enzymes (CYPs) of the human pathogen Mycobacterium tuberculosis (Mtb) and their endogenous redox partners, focusing on their biological function, expression, regulation, involvement in antibiotic resistance, and suitability for exploitation as antitubercular targets. The Mtb genome encodes twenty  CYPs and nine associated redox partners required for CYP catalytic activity. Transposon insertion mutagenesis studies have established the (conditional) essentiality of several of these enzymes for in vitro growth and host infection. Biochemical characterization of a handful of Mtb CYPs has revealed that they have specific physiological functions in bacterial virulence and persistence in the host. Analysis of the transcriptional response of Mtb CYPs and redox partners to external insults and to first-line antibiotics used to treat tuberculosis showed a diverse expression landscape, suggesting for some enzymes a potential role in drug resistance. Combining the knowledge about the physiological roles and expression profiles indicates that, at least five Mtb CYPs, CYP121A1, CYP125A1, CYP139A1, CYP142A1, and CYP143A1, as well as two ferredoxins, FdxA and FdxC, can be considered promising novel therapeutic targets.


Asunto(s)
Proteínas Bacterianas/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Mycobacterium tuberculosis/enzimología , Animales , Antituberculosos/farmacología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Biocatálisis , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/genética , Humanos , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Oxidación-Reducción , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología
15.
J Clin Monit Comput ; 33(2): 201-209, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30796643

RESUMEN

The microcirculation is the ultimate goal of hemodynamic optimization in the perioperative and critical care setting. In this fourth end-of-year summary of the Journal of Clinical Monitoring and Computing on this topic, we take a closer look at papers published in the last 2 years that focus on this important aspect. The majority of these papers investigated the use of either cerebral or peripheral tissue oxygen saturation, derived non-invasively using near infrared spectroscopy (NIRS). In some of these studies, the microcirculation was "provocated" by inducing short-term tissue hypoxia, allowing the assessment of functional microvascular reserve. Additionally, studies on technical differences between NIRS monitors are summarized, as well as studies investigating the feasibility of NIRS monitoring, mainly in the pediatric patient population. Last but not least, novel monitoring tools allow assessing oxygenation at a (sub)cellular level, and those papers incorporating these techniques are also reviewed here.


Asunto(s)
Cuidados Críticos/métodos , Microcirculación , Oximetría/métodos , Consumo de Oxígeno , Espectroscopía Infrarroja Corta/métodos , Animales , Aorta/patología , Monitorización Hemodinámica , Hemodinámica , Humanos , Hipoxia , Microscopía por Video/métodos , Oxígeno/metabolismo , Pediatría/métodos , Publicaciones Periódicas como Asunto
16.
Chem Res Toxicol ; 31(2): 116-126, 2018 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-29281794

RESUMEN

Detoxicating enzymes NAD(P)H:quinone oxidoreductase 1 (NQO1) and NRH:quinone oxidoreductase 2 (NQO2) catalyze the two-electron reduction of quinone-like compounds. The protective role of the polymorphic NQO1 and NQO2 enzymes is especially of interest in the liver as the major site of drug bioactivation to chemically reactive drug metabolites. In the current study, we quantified the concentrations of NQO1 and NQO2 in 20 human liver donors and NQO1 and NQO2 activities with quinone-like drug metabolites. Hepatic NQO1 concentrations ranged from 8 to 213 nM. Using recombinant NQO1, we showed that low nM concentrations of NQO1 are sufficient to reduce synthetic amodiaquine and carbamazepine quinone-like metabolites in vitro. Hepatic NQO2 concentrations ranged from 2 to 31 µM. NQO2 catalyzed the reduction of quinone-like metabolites derived from acetaminophen, clozapine, 4'-hydroxydiclofenac, mefenamic acid, amodiaquine, and carbamazepine. The reduction of the clozapine nitrenium ion supports association studies showing that NQO2 is a genetic risk factor for clozapine-induced agranulocytosis. The 5-hydroxydiclofenac quinone imine, which was previously shown to be reduced by NQO1, was not reduced by NQO2. Tacrine was identified as a potent NQO2 inhibitor and was applied to further confirm the catalytic activity of NQO2 in these assays. While the in vivo relevance of NQO2-catalyzed reduction of quinone-like metabolites remains to be established by identification of the physiologically relevant co-substrates, our results suggest an additional protective role of the NQO2 protein by non-enzymatic scavenging of quinone-like metabolites. Hepatic NQO1 activity in detoxication of quinone-like metabolites becomes especially important when other detoxication pathways are exhausted and NQO1 levels are induced.


Asunto(s)
Iminas/farmacología , NAD(P)H Deshidrogenasa (Quinona)/antagonistas & inhibidores , Quinona Reductasas/antagonistas & inhibidores , Quinonas/farmacología , Biocatálisis , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Iminas/síntesis química , Iminas/química , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/metabolismo , Estructura Molecular , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Oxidación-Reducción , Quinona Reductasas/metabolismo , Quinonas/síntesis química , Quinonas/química , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad
17.
Amino Acids ; 50(10): 1377-1390, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29978260

RESUMEN

In yeast, toxicity of acetaminophen (APAP), a frequently used analgesic and antipyretic drug, depends on ubiquitin-controlled processes. Previously, we showed a remarkable overlap in toxicity profiles between APAP and tyrosine, and a similarity with drugs like rapamycin and quinine, which induce degradation of the amino acid permease Tat2. Therefore, we investigated in yeast whether APAP reduced the expression levels of amino acid permeases. The protein levels of Tat2, Tat1, Mup1 and Hip1 were reduced, while the expression of the general permease Gap1 was increased, consistent with a nutrient starvation response. Overexpression of Tat1 and Tat2, but not Mup1, Hip1 and Gap1 conferred resistance to APAP. A tryptophan auxotrophic strain trp1Δ was more sensitive to APAP than wild-type and addition of tryptophan completely restored the growth restriction of trp1∆ upon APAP exposure, while tyrosine had an additive effect on APAP toxicity. Furthermore, intracellular aromatic amino acid concentrations were reduced upon APAP exposure. This effect was less prominent in ubiquitin-deficient yeast strains that were APAP resistant and showed a reduced degradation of high affinity amino acid permeases. APAP-induced changes in intracellular amino acid concentrations were also detected in hepatoma HepG2 cells indicating significance for humans.


Asunto(s)
Acetaminofén/toxicidad , Inhibidores Enzimáticos/toxicidad , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/enzimología , Triptófano/metabolismo , Sistemas de Transporte de Aminoácidos/antagonistas & inhibidores , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Aminoácidos/metabolismo , Células Hep G2 , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/antagonistas & inhibidores , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ubiquitina/metabolismo
18.
Appl Microbiol Biotechnol ; 102(21): 9231-9242, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30136203

RESUMEN

Mycobacterium tuberculosis (Mtb) codes for 20 cytochrome P450 enzymes (CYPs), considered potential drug-targets due to their essential roles in bacterial viability and host infection. Catalytic activity of mycobacterial CYPs is dependent on electron transfer from a NAD (P)H-ferredoxin-reductase (FNR) and a ferredoxin (Fd). Two FNRs (FdrA and FprA) and five ferredoxins (Fdx, FdxA, FdxC, FdxD, and Rv1786) have been found in the Mtb genome. However, as of yet, the cognate redox partnerships have not been fully established. This is confounded by the fact that heterologous redox partners are routinely used to reconstitute Mtb CYP metabolism. To this end, this study aimed to biochemically characterize and identify cognate redox partnerships for Mtb CYPs. Interestingly, all combinations of FNRs and ferredoxins were active in the reduction of oxidized cytochrome c, but steady-state kinetic assays revealed FdxD as the most efficient redox partner for FdrA, whereas Fdx coupled preferably with FprA. CYP121A1, CYP124A1, CYP125A1, and CYP142A1 metabolism with the cognate redox partners was reconstituted in vitro showing an unanticipated selectivity in the requirement for electron transfer partnership, which did not necessarily correlate with proximity in the genome. This is the first description of microbial P450 metabolism in which multiple ferredoxins are functionally linked to multiple CYPs.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Ferredoxinas/metabolismo , Mycobacterium tuberculosis/metabolismo , Secuencia de Aminoácidos , Transporte de Electrón/fisiología , Cinética , Oxidación-Reducción , Oxidorreductasas/metabolismo , Alineación de Secuencia
19.
J Clin Monit Comput ; 32(6): 969-976, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29569112

RESUMEN

Induction of general anesthesia frequently induces arterial hypotension, which is often treated with a vasopressor, such as phenylephrine. As a pure α-agonist, phenylephrine is conventionally considered to solely induce arterial vasoconstriction and thus increase cardiac afterload but not cardiac preload. In specific circumstances, however, phenylephrine may also contribute to an increase in venous return and thus cardiac output (CO). The aim of this study is to describe the initial time course of the effects of phenylephrine on various hemodynamic variables and to evaluate the ability of advanced hemodynamic monitoring to quantify these changes through different hemodynamic variables. In 24 patients, after induction of anesthesia, during the period before surgical stimulus, phenylephrine 2 µg kg-1 was administered when the MAP dropped below 80% of the awake state baseline value for > 3 min. The mean arterial blood pressure (MAP), heart rate (HR), end-tidal CO2 (EtCO2), central venous pressure (CVP), stroke volume (SV), CO, pulse pressure variation (PPV), stroke volume variation (SVV) and systemic vascular resistance (SVR) were recorded continuously. The values at the moment before administration of phenylephrine and 5(T5) and 10(T10) min thereafter were compared. After phenylephrine, the mean(SD) MAP, SV, CO, CVP and EtCO2 increased by 34(13) mmHg, 11(9) mL, 1.02(0.74) L min-1, 3(2.6) mmHg and 4.0(1.6) mmHg at T5 respectively, while both dynamic preload variables decreased: PPV dropped from 20% at baseline to 9% at T5 and to 13% at T10 and SVV from 19 to 11 and 14%, respectively. Initially, the increase in MAP was perfectly aligned with the increase in SVR, until 150 s after the initial increase in MAP, when both curves started to dissociate. The dissociation of the evolution of MAP and SVR, together with the changes in PPV, CVP, EtCO2 and CO indicate that in patients with anesthesia-induced hypotension, phenylephrine increases the CO by virtue of an increase in cardiac preload.


Asunto(s)
Anestesia General/efectos adversos , Gasto Cardíaco/efectos de los fármacos , Monitorización Hemodinámica/métodos , Hipotensión/tratamiento farmacológico , Hipotensión/etiología , Fenilefrina/uso terapéutico , Anciano , Femenino , Monitorización Hemodinámica/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Fenilefrina/administración & dosificación , Estudios Prospectivos , Factores de Tiempo , Vasoconstrictores/administración & dosificación , Vasoconstrictores/uso terapéutico
20.
Psychol Med ; 47(11): 1990-2001, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28374663

RESUMEN

BACKGROUND: The aim of this study was to assess the efficacy of meaning-centered group psychotherapy for cancer survivors (MCGP-CS) to improve personal meaning, compared with supportive group psychotherapy (SGP) and care as usual (CAU). METHOD: A total of 170 cancer survivors were randomly assigned to one of the three study arms: MCGP-CS (n = 57); SGP (n = 56); CAU (n = 57). The primary outcome measure was the Personal Meaning Profile (PMP; total score). Secondary outcome measures were subscales of the PMP, psychological well-being (Scales of Psychological Well-being; SPWB), post-traumatic growth (Posttraumatic Growth Inventory), Mental Adjustment to Cancer (MAC), optimism (Life Orientation Test-Revised), hopelessness (Beck's Hopelessness Scale), psychological distress (anxiety and depression, Hospital Anxiety and Depression Scale; HADS) and quality of life (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire; EORTC QLQ-C30). Outcome measures were assessed before randomization, post-intervention, and after 3 and 6 months of follow-up (FU). RESULTS: Linear mixed model analyses (intention-to-treat) showed significant differences between MCGP-CS, SGP and CAU on the total PMP score, and on (sub)scales of the PMP, SPWB, MAC and HADS. Post-hoc analyses showed significantly stronger treatment effects of MCGP-CS compared with CAU on personal meaning (d = 0.81), goal-orientedness (d = 1.07), positive relations (d = 0.59), purpose in life (d = 0.69); fighting spirit (d = 0.61) (post-intervention) and helpless/hopeless (d = -0.87) (3 months FU); and distress (d = -0.6) and depression (d = -0.38) (6 months FU). Significantly stronger effects of MCGP-CS compared with SGP were found on personal growth (d = 0.57) (3 months FU) and environmental mastery (d = 0.66) (6 months FU). CONCLUSIONS: MCGP-CS is an effective intervention for cancer survivors to improve personal meaning, psychological well-being and mental adjustment to cancer in the short term, and to reduce psychological distress in the long run.


Asunto(s)
Supervivientes de Cáncer/psicología , Depresión/psicología , Optimismo/psicología , Evaluación de Resultado en la Atención de Salud , Satisfacción Personal , Psicoterapia de Grupo/métodos , Calidad de Vida/psicología , Adulto , Anciano , Ansiedad/psicología , Ansiedad/terapia , Depresión/terapia , Femenino , Esperanza , Humanos , Masculino , Persona de Mediana Edad
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