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1.
ASAIO J ; 70(9): 734-740, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38569184

RESUMEN

Severe right heart failure, often overlooked and challenging to manage, has prompted a growing interest in innovative approaches to provide functional support. This study uses experimentation in large porcine models to introduce a novel prototype of a pulsatile mechanical circulatory support device and document its effects when deployed as a right ventricular assist device (RVAD). The pulsatile ventricular assist platform (pVAP), featuring a membrane pump driven by an intra-aortic balloon pump console, actively generates pulsatile flow to propel right ventricular blood into the pulmonary artery. This novel prototype demonstrates promising potential in addressing the challenges of right heart failure management. After preliminary in vitro assessments, the pVAP was tested on seven porcine models in a healthy state and after the induction of right ventricular failure. During the procedure, a set of standard ( ie , standard-of-care) hemodynamic measurements was obtained. Additionally, invasive pressure-volume loop analysis was employed to examine left ventricular hemodynamics. Results indicated that activation of the pVAP during right ventricular failure significantly improved systemic hemodynamics and enhanced left ventricular function. This study sheds light on the potential of the pVAP in managing right heart failure.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Hemodinámica , Contrapulsador Intraaórtico , Flujo Pulsátil , Animales , Porcinos , Hemodinámica/fisiología , Contrapulsador Intraaórtico/instrumentación , Contrapulsador Intraaórtico/métodos , Flujo Pulsátil/fisiología , Insuficiencia Cardíaca/cirugía , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/fisiopatología , Disfunción Ventricular Derecha/fisiopatología , Disfunción Ventricular Derecha/cirugía , Disfunción Ventricular Derecha/terapia
2.
Small ; 20(33): e2400348, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38564790

RESUMEN

Production of green hydrogen (H2) is a sustainable process able to address the current energy crisis without contributing to long-term greenhouse gas emissions. Many Ag-based catalysts have shown promise for light-driven H2 generation, however, pure Ag-in its bulk or nanostructured forms-suffers from slow electron transfer kinetics and unfavorable Ag─H bond strength. It is demonstrated that the complexation of Ag with various chalcogenides can be used as a tool to optimize these parameters and reach improved photocatalytic performance. In this work, metal-organic-chalcogenolate assemblies (MOCHAs) are introduced as effective catalysts for light-driven hydrogen evolution reaction (HER) and investigate their performance and structural stability by examining a series of AgXPh (X = S, Se, and Te) compounds. Two catalyst-support sensitization strategies are explored: by designing MOCHA/TiO2 composites and by employing a common Ru-based photosensitizer. It is demonstrated that the heterogeneous approach yields stable HER performance but involves a catalyst transformation at the initial stage of the photocatalytic process. In contrast to this, the visible-light-driven MOCHA-dye dyad shows similar HER activity while also ensuring the structural integrity of the MOCHAs. The work shows the potential of MOCHAs in constructing photosystems for catalytic H2 production and provides a direct comparison between known AgXPh compounds.

3.
Sustain Energy Fuels ; 8(6): 1225-1235, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38481764

RESUMEN

This study investigates the hydrogen evolution reaction (HER) efficiency of two photosystems incorporating an all-inorganic molecular thiomolybdate [Mo3S13]2- cluster as a HER catalyst. First, we delve into the performance of a homogeneous [Mo3S13]2-/[Ru(bpy)3]2+ (Mo3/Ru) dyad which demonstrates high turnover frequencies (TOFs) and apparent quantum yields (AQYs) at 445 nm approaching the level of 0.5%, yet its performance is marked by pronounced deactivation. In contrast, a heterogeneous approach involves anchoring [Mo3S13]2- onto graphitic carbon nitride (GCN) nanosheets through weak electrostatic association with its triazine/heptazine scaffold. [Mo3S13]2-/GCN (Mo3/GCN) displays effective H2 generation under visible light, with TOF metrics on par with those of its homogeneous analog. Although substantial leaching of [Mo3S13]2- species from the Mo3/GCN surface occurs, the remaining {Mo3}-based centers demonstrate impressive stability, leading to enduring HER performance, starkly distinguishing it from the homogeneous Mo3/Ru photosystem. Photoluminescence (PL) quenching experiments confirm that the performance of Mo3/GCN is not limited by the quality of the inorganic interface, but could be optimized by using higher surface area supports or a higher concentration of [Mo3S13]2- sites. Our findings showcase complexities underlying the evaluation and comparison of photosystems comprising well-defined catalytic centers and pave the way for developing analogous surface-supported (photo)catalysts with broad use in energy applications.

5.
Environ Res ; 241: 117348, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37821064

RESUMEN

Attributional life cycle assessment study examines the environmental impact of raw materials, machinery, and unit operations. In the present work, an attributional life cycle assessment (LCA) was employed to assess the environmental and greenhouse gas impacts of a shrimp feed production system. A commercial shrimp feed mill in Tamil Nadu, India, provided inventory data for one-ton shrimp feed (functional unit) for a Cradle-to-Gate evaluation using environmental impact methodologies, specifically Impact 2002+ in SimaPro® (V9.3.0.3) software. The results showed that human health (0.003357 DALY), ecosystem quality (2720.518 PDF × m2 × yr), climate change (2031.696 kg CO2 eq), and resources (71019.42 MJ primary) were the most significantly impacted. The human health category was found to be the most prominent after normalization and weighting (0.47 pt), and strategies were suggested accordingly. The GWP20 and GWP100 measures for long-term climate change were calculated to be 8.7 and 7.33 kg CO2 eq, respectively. Cast iron used in machinery production (GWP 20-15.40%, GWP100-134.5%) and electricity use (GWP 20-6.13%, GWP 100-6.9%) accounted for sizable portions of the burden. Feed production is estimated to contribute 0.2% of global CO2 emissions within the proposed global context. These findings are significant regarding economically and environmentally sustainable shrimp feed production worldwide.


Asunto(s)
Gases de Efecto Invernadero , Humanos , Ecosistema , Dióxido de Carbono/análisis , India , Ambiente , Acuicultura
7.
Proc Natl Acad Sci U S A ; 120(51): e2221680120, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38096407

RESUMEN

Animals integrate sensory information from the environment and display various behaviors in response to external stimuli. In Caenorhabditis elegans hermaphrodites, 33 types of sensory neurons are responsible for chemosensation, olfaction, and mechanosensation. However, the functional roles of all sensory neurons have not been systematically studied due to the lack of facile genetic accessibility. A bipartite cGAL-UAS system has been previously developed to study tissue- or cell-specific functions in C. elegans. Here, we report a toolkit of new cGAL drivers that can facilitate the analysis of a vast majority of the 60 sensory neurons in C. elegans hermaphrodites. We generated 37 sensory neuronal cGAL drivers that drive cGAL expression by cell-specific regulatory sequences or intersection of two distinct regulatory regions with overlapping expression (split cGAL). Most cGAL-drivers exhibit expression in single types of cells. We also constructed 28 UAS effectors that allow expression of proteins to perturb or interrogate sensory neurons of choice. This cGAL-UAS sensory neuron toolkit provides a genetic platform to systematically study the functions of C. elegans sensory neurons.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Receptoras Sensoriales/metabolismo
8.
PeerJ ; 11: e16561, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38107566

RESUMEN

Marine sponges are prominent organisms of the benthic coral reef fauna, providing important ecosystem services. While there have been increasing reports that sponges are becoming one of the dominant benthic organisms in some locations and ecoregions (e.g. Caribbean), they can be impacted by changing environmental conditions. This study presents the first documentation of a mass mortality event of the barrel sponge Xestospongia sp. in the lower Gulf of Thailand and its consequences on population dynamics and size distribution. Two anthropogenic impacted reefs (Haad Khom and Mae Haad) of the island Koh Phangan and two anthropogenic non-impacted reefs of the islands Koh Yippon and Hin Yippon within the Mu Ko Ang Thong Marine National Park were surveyed in the years 2015 and 2016. The results showed a strong shift in population densities at Koh Phangan. Fatal "bleaching" ending up in mass mortality was observed for these reefs in 2015. Xestospongia sp. abundance decreased from 2015 to 2016 by 80.6% at Haad Khom and by 98.4% at Mae Haad. Sponges of all sizes were affected, and mortality occurred regardless of the survey depth (4 and 6 m). However, Xestospongia population densities in the Marine Park were at a constant level during the surveys. The abundances in 2015 were 65% higher at the Marine Park than at Koh Phangan and 92% higher in 2016. The most likely causes of the mass mortality event was a local harmful algal bloom event, pathogens, undetected local higher water temperatures, or a combination of these factors, whereas sea surface temperature analyses showed no marine heatwave during the observed mass mortality event in 2015. Considering the ecological importance of sponges such as Xestospongia sp., long-term monitoring of reefs and their environmental parameters should be implemented to prevent such mass die-offs.


Asunto(s)
Poríferos , Xestospongia , Animales , Ecosistema , Tailandia/epidemiología , Dinámica Poblacional
9.
Sci Rep ; 13(1): 18552, 2023 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-37899422

RESUMEN

In patients with left ventricular assist device (LVAD), infections and thrombotic events represent severe complications. We investigated device-specific local and systemic inflammation and its impact on cerebrovascular events (CVE) and mortality. In 118 LVAD patients referred for 18F-FDG-PET/CT, metabolic activity of LVAD components, thoracic aortic wall, lymphoid and hematopoietic organs, was quantified and correlated with clinical characteristics, laboratory findings, and outcome. Driveline infection was detected in 92/118 (78%) patients by 18F-FDG-PET/CT. Activity at the driveline entry site was associated with increased signals in aortic wall (r = 0.32, p < 0.001), spleen (r = 0.20, p = 0.03) and bone marrow (r = 0.20, p = 0.03), indicating systemic interactions. Multivariable analysis revealed independent associations of aortic wall activity with activity of spleen (ß = 0.43, 95% CI 0.18-0.68, p < 0.001) and driveline entry site (ß = 0.04, 95% CI 0.01-0.06, p = 0.001). Twenty-two (19%) patients suffered CVE after PET/CT. In a binary logistic regression analysis metabolic activity at the driveline entry site missed the level of significance as an influencing factor for CVE after adjusting for anticoagulation (OR = 1.16, 95% CI 1-1.33, p = 0.05). Metabolic activity of the subcutaneous driveline (OR = 1.13, 95% CI 1.02-1.24, p = 0.016) emerged as independent risk factor for mortality. Molecular imaging revealed systemic inflammatory interplay between thoracic aorta, hematopoietic organs, and infected device components in LVAD patients, the latter predicting CVE and mortality.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Infecciones Relacionadas con Prótesis , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Corazón Auxiliar/efectos adversos , Infecciones Relacionadas con Prótesis/etiología , Inflamación/etiología , Insuficiencia Cardíaca/complicaciones , Estudios Retrospectivos
10.
Science ; 382(6668): 262-263, 2023 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-37856580

RESUMEN

Hierarchical organization of memory is observed in the brains of rats.


Asunto(s)
Hipocampo , Memoria Episódica , Neuronas , Animales , Ratas , Neuronas/fisiología , Hipocampo/citología , Hipocampo/fisiología
12.
J Gen Virol ; 104(8)2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37650875

RESUMEN

Influenza A viruses of the H2N2 subtype sparked a pandemic in 1957 and circulated in humans until 1968. Because A/H2N2 viruses still circulate in wild birds worldwide and human population immunity is low, the transmissibility of six avian A/H2N2 viruses was investigated in the ferret model. None of the avian A/H2N2 viruses was transmitted between ferrets, suggesting that their pandemic risk may be low. The transmissibility, receptor binding preference and haemagglutinin (HA) stability of human A/H2N2 viruses were also investigated. Human A/H2N2 viruses from 1957 and 1958 bound to human-type α2,6-linked sialic acid receptors, but the 1958 virus had a more stable HA, indicating adaptation to replication and spread in the new host. This increased stability was caused by a previously unknown stability substitution G205S in the 1958 H2N2 HA, which became fixed in A/H2N2 viruses after 1958. Although individual substitutions were identified that affected the HA receptor binding and stability properties, they were not found to have a substantial effect on transmissibility of A/H2N2 viruses via the air in the ferret model. Our data demonstrate that A/H2N2 viruses continued to adapt during the first year of pandemic circulation in humans, similar to what was previously shown for the A/H1N1pdm09 virus.


Asunto(s)
Subtipo H2N2 del Virus de la Influenza A , Virus de la Influenza A , Animales , Humanos , Subtipo H2N2 del Virus de la Influenza A/genética , Hurones , Pandemias
13.
Arch Orthop Trauma Surg ; 143(10): 6477-6485, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37486446

RESUMEN

BACKGROUND: Carpal tunnel syndrome, A1 annular pulley stenosis and Dupuytren's contracture are among the most common conditions of the hand. In this study, we investigated the impact of surgical procedure on hand grip strength and high-resolution spatial load distribution in individuals suffering from those diseases over a follow-up period of one year. MATERIALS AND METHODS: In this prospective study, data of 9 patients with carpal tunnel syndrome, 12 patients with A1 annular pulley stenosis and 7 patients with Dupuytren's contracture were evaluated. Only patients with unilateral disease were included providing the contralateral hand as an intra-individual control. Grip strength was measured with cylindrical instruments in two different sizes with respect to the hand size of the patients. Maximum and average values of grip strength as well as spatial load distribution in each finger, thenar, hypothenar and palm were analyzed. Data of the affected patients were collected preoperatively and 6 weeks, 6 months and 1 year postoperatively. Grip strength and spatial load distribution were compared preoperatively to postoperatively. In addition, DASH score, Levine score, 2-point discrimination and degree of flexion contracture were assessed. RESULTS: The patients with A1 annular pulley stenosis showed a significant increase in grip strength 6 months and one year postoperatively. Patients with carpal tunnel syndrome and Dupuytren's contracture showed no significant difference in grip strength over the course of time. An increase in the percentual grip strength of the thenar in patients with carpal tunnel disease and within the affected finger in A1 annular pulley stenosis was observed over the course of time. The DASH score was significantly lower in all patient cohorts one year postoperatively. CONCLUSION: Surgical procedure in carpal tunnel syndrome, A1 annular ligament stenosis and Dupuytren's contracture improves the functionality of the hand in everyday life. Some areas of the hand seem to compensate other weaker areas in grip strength.


Asunto(s)
Síndrome del Túnel Carpiano , Contractura de Dupuytren , Humanos , Contractura de Dupuytren/cirugía , Síndrome del Túnel Carpiano/cirugía , Fuerza de la Mano , Estudios Prospectivos , Constricción Patológica
14.
Front Cardiovasc Med ; 10: 1143886, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37187792

RESUMEN

We report here the first clinical use of the left atrial appendage (LAA) for epicardial micrograft transplantation during left ventricular assist device (LVAD) implantation. Previously, a sample from the right atrial appendage (RAA) has been available for processing and administering micrograft therapy in cardiac surgery. Both LAA and RAA are rich sources of various types of myocardial cells and are capable of providing both paracrine and cellular support to the failing myocardium. The surgical approach of LAA micrografting facilitates epicardial micrograft therapy dose escalation and treatment of larger myocardial areas than done previously. Moreover, as collection of treated vs. untreated tissues from the recipient heart is possible following LVAD implantation at the time of heart transplantation, the evaluation of the therapy's mechanism of action can be further deciphered at cellular and molecular levels. This LAA modification of the epicardial micrografting technique has the overall potential to facilitate the adoption of cardiac cell therapy during heart surgery.

15.
Commun Chem ; 6(1): 43, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859623

RESUMEN

Today, many essential industrial processes depend on syngas. Due to a high energy demand and overall cost as well as a dependence on natural gas as its precursor, alternative routes to produce this valuable mixture of hydrogen and carbon monoxide are urgently needed. Electrochemical syngas production via two competing processes, namely carbon dioxide (CO2) reduction and hydrogen (H2) evolution, is a promising method. Often, noble metal catalysts such as gold or silver are used, but those metals are costly and have limited availability. Here, we show that metal-organic chalcogenolate assemblies (MOCHAs) combine several properties of successful electrocatalysts. We report a scalable microwave-assisted synthesis method for highly crystalline MOCHAs ([AgXPh] ∞: X = Se, S) with high yields. The morphology, crystallinity, chemical and structural stability are thoroughly studied. We investigate tuneable syngas production via electrocatalytic CO2 reduction and find the MOCHAs show a maximum Faraday efficiency (FE) of 55 and 45% for the production of carbon monoxide and hydrogen, respectively.

16.
J Cardiovasc Surg (Torino) ; 64(1): 121-129, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36763071

RESUMEN

BACKGROUND: Total artificial heart (TAH) implantation is a rarely performed procedure. Contrarily, left ventricular assist device (VAD) implantation is rather common in many centers. As transplantation is quantitatively limited cardiac replacement with artificial hearts is a viable alternative in the treatment of severe biventricular heart failure. An alternative to TAH is the implantation of two VADs in a TAH configuration. We hereby present the first multi-center study on 3-months outcomes of patients treated by cardiectomy and placement of two HeartMate 3s in a TAH configuration. METHODS: We retrospectively investigated a cohort of 15 patients that underwent HM3-TAH-implantation at three international institutions. Follow-up was 3 months after implantation. Baseline, intra- and postoperative parameters as well as survival data and adverse events were collected. RESULTS: A total of 1089 days on HM3-TAH were observed. Thirty-day survival after HM3-TAH implantation was 53% (8/15) and three month survival was 40% (6/15). The longest duration on device was 274 days. Causes of death were multi-organ failure, sepsis, and neurological adverse events. No technical complications were documented. Two patients remained on the device. Four patients (26%) were successfully bridged to transplantation. CONCLUSIONS: The implantation of two HeartMate 3s in a TAH configuration is a last resort and off-label concept in cases of extreme biventricular heart failure. In a diligently selected patient cohort, HM3-TAH implantation is a feasible method to increase the chance of survival in a severely ill patient cohort and successfully bridge patients to heart transplantation that would otherwise have died.


Asunto(s)
Insuficiencia Cardíaca , Trasplante de Corazón , Corazón Artificial , Corazón Auxiliar , Humanos , Corazón Auxiliar/efectos adversos , Estudios Retrospectivos , Corazón Artificial/efectos adversos , Insuficiencia Cardíaca/cirugía
17.
Artif Organs ; 47(2): 380-386, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36148849

RESUMEN

BACKGROUND: Driveline (DL) damages are a common difficulty among ventricular assist devices (VAD). Repairing the electrical fibers inside the DL on a running pump is hazardous and requires technical expertise, which is not easily available on site. A new feature of the HeartMate3 (Abbott, U.S.A.) LVAD is a modular driveline that allows an easy exchange of the DL cord. In this report we analyze our experiences with this feature. METHODS: We performed a retrospective analysis of 302 patients who underwent either HeartMate II or HeartMate 3 implantation between February 2004 and September 2021. Patients were screened for driveline faults and need for exchange or repair of driveline or VAD exchange. Documented were baseline characteristics, reasons for DL or VAD exchange, and complications. Follow-up was three months after the procedure. RESULTS: We present a cohort of 302 patients who underwent either HMII (n = 107;35.4%) or HM 3 (n = 195; 64.5%) implantation. Out of those, 40 patients (40/302; 13.2%) required driveline repair (DLRe) or exchange (DLEx). Out of 107 HMII patients, 9 showed severe DL damages (9/107; 8.4%). Six patients (6/9; 66.6%) underwent DLRe, two patients (2/6; 33.3%) required VAD exchange after DLRe, one patient (1/2;50%) experienced emergency VAD exchange after pump stop. The DLRe procedure in the other four patients (4/6; 66.6%) was successful. Due to damage to the internal driveline two patients (2/9; 22.2%) underwent emergency device exchange and one patient (1/9;11.1%) was listed for transplantation. 31 out 195 HM3 patients underwent exchange of the modular DL. In none of the cases, damages of the internal fibers were the reasons for the exchange. In 100% of the cases, damages of the external coating were the reason for DL exchange. In none of the cases, complications occurred after the exchange procedure. CONCLUSIONS: Driveline damages are a habitual, recurrent complication in VAD patients. The exchange of the modular driveline cable of the HM3 is feasible and safe compared to the conventional DL repair in HMII patients. Risky repair attempts and surgical LVAD exchange due to major damages of the electrical fibers can be avoided successfully by the new feature of HM3 driveline.


Asunto(s)
Insuficiencia Cardíaca , Trasplante de Corazón , Corazón Auxiliar , Humanos , Insuficiencia Cardíaca/cirugía , Insuficiencia Cardíaca/etiología , Estudios Retrospectivos , Corazón Auxiliar/efectos adversos
18.
J Pers Med ; 12(12)2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36556274

RESUMEN

Peri-prosthetic breast infections pose a risk of severe complications after breast implant surgery. The need to remove the breast implant, control the infection and perform additional surgical procedures are the consequences. Reimplantation of an alloplastic implant is only appropriate after an infection-free interval. In this retrospective cohort study, we investigated the effectiveness of negative pressure wound treatment with instillation and dwell time (NPWTi-d) on peri-prosthetic breast infections in combination with implant removal and antibiotic therapy. Twelve patients treated with NPWTi-d due to breast implant infection were included in the study. The bacterial burden was analyzed using wound swabs before and after NPWTi-d. Additionally, laboratory values were determined before NPWTi-d and immediately before wound closure. A total of 13 peri-prosthetic breast infections in 12 patients were treated using implant removal and NPWTi-d. In 76.9% (n = 10) of the cases, the patients had undergone alloplastic breast reconstruction following cancer-related mastectomy, whereas 23.1% (n = 3) of the patients had undergone breast augmentation for cosmetic reasons. The bacterial burden in the breast pocket decreased statistically significant after implant removal and NPWTi-d. No shift from Gram-positive to Gram-negative bacteria was observed. Inflammatory markers rapidly decreased following treatment. NPWTi-d had a positive impact on the healing process after peri-prosthetic breast infections, leading to a decrease in bacterial burden within the wounds and contributing to uneventful healing. Therefore, secondary reimplantation of breast prostheses might be positively influenced when compared to conventional implant removal and simple secondary closure. Further studies are required to conclusively establish the beneficial long-term effects of using NPWTi-d for the treatment of peri-prosthetic breast infections.

19.
Artículo en Inglés | MEDLINE | ID: mdl-36078450

RESUMEN

BACKGROUND: Research in accidental hypothermia focuses on trauma patients, patients exposed to cold environments or patients after drowning but rarely on hypothermia in combination with intoxications or on medical or neurological issues. The aim of this retrospective single-centre cohort study was to define the aetiologies, severity and relative incidences of accidental hypothermia, methods of measuring temperature and in-hospital mortality. METHODS: The study included patients ≥18 years with a documented body temperature ≤35 °C who were admitted to the emergency department (ED) of the University Hospital in Bern between 2000 and 2019. RESULTS: 439 cases were included, corresponding to 0.32 per 1000 ED visits. Median age was 55 years (IQR 39-70). A total of 167 patients (38.0%) were female. Furthermore, 63.3% of the patients suffered from mild, 24.8% from moderate and 11.9% from severe hypothermia. Exposure as a single cause for accidental hypothermia accounted for 12 cases. The majority were combinations of hypothermia with trauma (32.6%), medical conditions (34.2%), neurological conditions (5.2%), intoxications (20.3%) or drowning (12.0%). Overall mortality was 22.3% and depended on the underlying causes, severity of hypothermia, age and sex.


Asunto(s)
Ahogamiento , Hipotermia , Estudios de Cohortes , Femenino , Humanos , Hipotermia/epidemiología , Hipotermia/etiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Suiza/epidemiología , Centros Traumatológicos
20.
Nature ; 608(7923): 586-592, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35859170

RESUMEN

The ability to associate temporally segregated information and assign positive or negative valence to environmental cues is paramount for survival. Studies have shown that different projections from the basolateral amygdala (BLA) are potentiated following reward or punishment learning1-7. However, we do not yet understand how valence-specific information is routed to the BLA neurons with the appropriate downstream projections, nor do we understand how to reconcile the sub-second timescales of synaptic plasticity8-11 with the longer timescales separating the predictive cues from their outcomes. Here we demonstrate that neurotensin (NT)-expressing neurons in the paraventricular nucleus of the thalamus (PVT) projecting to the BLA (PVT-BLA:NT) mediate valence assignment by exerting NT concentration-dependent modulation in BLA during associative learning. We found that optogenetic activation of the PVT-BLA:NT projection promotes reward learning, whereas PVT-BLA projection-specific knockout of the NT gene (Nts) augments punishment learning. Using genetically encoded calcium and NT sensors, we further revealed that both calcium dynamics within the PVT-BLA:NT projection and NT concentrations in the BLA are enhanced after reward learning and reduced after punishment learning. Finally, we showed that CRISPR-mediated knockout of the Nts gene in the PVT-BLA pathway blunts BLA neural dynamics and attenuates the preference for active behavioural strategies to reward and punishment predictive cues. In sum, we have identified NT as a neuropeptide that signals valence in the BLA, and showed that NT is a critical neuromodulator that orchestrates positive and negative valence assignment in amygdala neurons by extending valence-specific plasticity to behaviourally relevant timescales.


Asunto(s)
Complejo Nuclear Basolateral , Aprendizaje , Vías Nerviosas , Neurotensina , Castigo , Recompensa , Complejo Nuclear Basolateral/citología , Complejo Nuclear Basolateral/fisiología , Calcio/metabolismo , Señales (Psicología) , Plasticidad Neuronal , Neurotensina/metabolismo , Optogenética , Núcleos Talámicos/citología , Núcleos Talámicos/fisiología
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