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1.
Cell ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38942013

RESUMEN

The ability of proteins and RNA to coalesce into phase-separated assemblies, such as the nucleolus and stress granules, is a basic principle in organizing membraneless cellular compartments. While the constituents of biomolecular condensates are generally well documented, the mechanisms underlying their formation under stress are only partially understood. Here, we show in yeast that covalent modification with the ubiquitin-like modifier Urm1 promotes the phase separation of a wide range of proteins. We find that the drop in cellular pH induced by stress triggers Urm1 self-association and its interaction with both target proteins and the Urm1-conjugating enzyme Uba4. Urmylation of stress-sensitive proteins promotes their deposition into stress granules and nuclear condensates. Yeast cells lacking Urm1 exhibit condensate defects that manifest in reduced stress resilience. We propose that Urm1 acts as a reversible molecular "adhesive" to drive protective phase separation of functionally critical proteins under cellular stress.

2.
Microorganisms ; 12(6)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38930587

RESUMEN

We present the validity of using an ultrasensitive enzyme-linked immunosorbent assay (ELISA) for quantifying high-risk human papillomavirus (HPV) 16 E7 oncoproteins in urine specimens as a noninvasive method of analyzing the oncogenic activity of HPV. Some reports claim that the oncogenic activity of HPV is a more relevant clinical indicator than the presence of HPV DNA for estimating malignant potential. In the present study, urine containing HPV16 and related types were selected by uniplex E6/E7 polymerase chain reaction and classified according to the pathologic diagnosis of cervical intraepithelial neoplasia (CIN) in cervical biopsy specimens. Our ultrasensitive ELISA was able to detect attomole levels of HPV16 E7 oncoproteins, and it detected HPV16-positive SiHa cells at >500 cells/mL without detecting HPV18-positive cells. Our ELISA results showed E7 oncoproteins in 80% (4/5) of urine specimens from women with HPV16-positive CIN1, 71% (5/7) of urine specimens from CIN2 patients, and 38% (3/8) of urine specimens from CIN3 patients. Some urine specimens with undetectable E7 oncoproteins were thought to be negative for live HPV 16-positive cells or in an inactivated state of infection. These results provide the basis for assessing oncogenic activity by quantifying E7 oncoproteins in patient urine.

3.
NPJ Vaccines ; 9(1): 119, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926425

RESUMEN

Persistent infection with high-risk human papillomavirus (HPV) is widely recognized as the primary cause of cervical and other malignant cancers. There are six licensed prophylactic vaccines available against HPV, but none of them shows any significant therapeutic effect on pre-existing infections or lesions. Thus, a prophylactic vaccine also endowed with therapeutic activity would afford protection regardless of the vaccine recipients HPV-infection status. Here, we describe the refinement and further potentiation of a dual-purpose HPV nanoparticle vaccine (hereafter referred to as cPANHPVAX) relying on eight different HPV L2 peptide epitopes and on the E7 oncoantigens from HPV16 and 18. cPANHPVAX not only induces anti-HPV16 E7 cytotoxic T-cell responses in C57BL/6 mice, but also anti-HPV18 E7 T-cell responses in transgenic mice with the A2.DR1 haplotype. These cytotoxic responses add up to a potent, broad-coverage humoral (HPV-neutralizing) response. cPANHPVAX safety was further improved by deletion of the pRb-binding domains of E7. Our dual-purpose vaccine holds great potential for clinical translation as an immune-treatment capable of targeting active infections as well as established HPV-related malignancies, thus benefiting both uninfected and infected individuals.

4.
Biomedicines ; 12(6)2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38927543

RESUMEN

Cardiac xenotransplantation has seen remarkable success in recent years and is emerging as the most promising alternative to human cardiac allotransplantation. Despite these achievements, acute vascular rejection still presents a challenge for long-term xenograft acceptance and new insights into innate and adaptive immune responses as well as detailed characterizations of signaling pathways are necessary. In allotransplantation, endothelial cells and their sugar-rich surface-the endothelial glycocalyx-are known to influence organ rejection. In xenotransplantation, however, only in vitro data exist on the role of the endothelial glycocalyx so far. Thus, in the current study, we analyzed the changes of the endothelial glycocalyx components hyaluronan, heparan sulfate and syndecan-1 after pig-to-baboon cardiac xenotransplantations in the perioperative (n = 4) and postoperative (n = 5) periods. These analyses provide first insights into changes of the endothelial glycocalyx after pig-to-baboon cardiac xenotransplantation and show that damage to the endothelial glycocalyx seems to be comparable or even less pronounced than in similar human settings when current strategies of cardiac xenotransplantation are applied. At the same time, data from the experiments where current strategies, like non-ischemic preservation, growth inhibition or porcine cytomegalovirus (a porcine roseolovirus (PCMV/PRV)) elimination could not be applied indicate that damage of the endothelial glycocalyx also plays an important role in cardiac xenotransplantation.

5.
Oral Maxillofac Surg ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38918316

RESUMEN

OBJECTIVES: The purpose of this study was to compare two different designs of three-dimensional osteosynthesis plates for their suitability in the treatment of mandibular angle fractures in terms of sufficient fracture healing and concomitant complications. MATERIALS AND METHODS: Retrospectively a total of 54 patients with 56 mandibular angle fractures were evaluated. Two different types of three-dimensional plates from the Medartis Trilock system were analyzed: (A) Square design plate (☐-plate) with a thickness of 1.0 mm, and (B) triangular-shaped 3D-plate (△-plate) with a thickness of 1.3 mm. Patient demographics, fracture mechanism and intraoperative details were recorded during an average follow-up period of 1 year. RESULTS: The utilization of △-plates was observed to entail a considerably lengthier surgical time in contrast to ☐-plate systems (P = 0.037). The application of △-plate showed a tendency of higher incidence of major complications than ☐-plate (P = 0.06), as evidenced by the occurrence of non-union in 2 out of 22 cases, resulting in higher surgical revision rate for △-plate (P = 0.027). CONCLUSION: Sufficient treatment of mandibular angle fractures is feasible by using 1.0 mm thick, square shaped three-dimensional plate systems. The use of thicker three-dimensional osteosynthesis plates seems to significantly increase the operating time and complication rates, whereby the geometry of the plate seems to have an influence. CLINICAL RELEVANCE: The plate design could have an impact on treatment outcomes of mandibular angle fractures. TRIAL REGISTRATION NUMBER: Not applicable.

6.
BMC Med Educ ; 24(1): 666, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886688

RESUMEN

BACKGROUND: Advanced Trauma Life Support (ATLS) is the gold standard of initial assessment of trauma patients and therefore a widely used training program for medical professionals. Practical application of the knowledge taught can be challenging for medical students and inexperienced clinicians. Simulation-based training, including virtual reality (VR), has proven to be a valuable adjunct to real-world experiences in trauma education. Previous studies have demonstrated the effectiveness of VR simulations for surgical and technical skills training. However, there is limited evidence on VR simulation training specifically for trauma education, particularly within the ATLS curriculum. The purpose of this pilot study is to evaluate the feasibility, effectiveness, and acceptance of using a fully immersive VR trauma simulation to prepare medical students for the ATLS course. METHODS: This was a prospective randomised controlled pilot study on a convenience sample of advanced medical students (n = 56; intervention group with adjunct training using a commercially available semi-automated trauma VR simulation, n = 28, vs control group, n = 28) taking part in the ATLS course of the Military Physician Officer School. Feasibility was assessed by evaluating factors related to technical factors of the VR training (e.g. rate of interruptions and premature termination). Objective and subjective effectiveness was assessed using confidence ratings at four pre-specified points in the curriculum, validated surveys, clinical scenario scores, multiple choice knowledge tests, and ATLS final clinical scenario and course pass rates. Acceptance was measured using validated instruments to assess variables of media use (Technology acceptance, usability, presence and immersion, workload, and user satisfaction). RESULTS: The feasibility assessment demonstrated that only one premature termination occurred and that all remaining participants in the intervention group correctly stabilised the patient. No significant differences between the two groups in terms of objective effectiveness were observed (p = 0.832 and p = 0.237 for the pretest and final knowledge test, respectively; p = 0.485 for the pass rates for the final clinical scenario on the first attempt; all participants passed the ATLS course). In terms of subjective effectiveness, the authors found significantly improved confidence post-VR intervention (p < .001) in providing emergency care using the ATLS principles. Perceived usefulness in the TEI was stated with a mean of 4 (SD 0.8; range 0-5). Overall acceptance and usability of the VR simulation was rated as positive (System Usability Scale total score mean 79.4 (SD 11.3, range 0-100). CONCLUSIONS: The findings of this prospective pilot study indicate the potential of using VR trauma simulations as a feasible and acceptable supplementary tool for the ATLS training course. Where objective effectiveness regarding test and scenario scores remained unchanged, subjective effectiveness demonstrated improvement. Future research should focus on identifying specific scenarios and domains where VR can outperform or enhance traditional learning methods in trauma simulation.


Asunto(s)
Atención de Apoyo Vital Avanzado en Trauma , Entrenamiento Simulado , Realidad Virtual , Humanos , Proyectos Piloto , Estudios Prospectivos , Masculino , Femenino , Adulto , Competencia Clínica , Estudios de Factibilidad , Estudiantes de Medicina , Curriculum , Evaluación Educacional , Adulto Joven
8.
Front Behav Neurosci ; 18: 1399716, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38835838

RESUMEN

Introduction: In order to successfully move from place to place, our brain often combines sensory inputs from various sources by dynamically weighting spatial cues according to their reliability and relevance for a given task. Two of the most important cues in navigation are the spatial arrangement of landmarks in the environment, and the continuous path integration of travelled distances and changes in direction. Several studies have shown that Bayesian integration of cues provides a good explanation for navigation in environments dominated by small numbers of easily identifiable landmarks. However, it remains largely unclear how cues are combined in more complex environments. Methods: To investigate how humans process and combine landmarks and path integration in complex environments, we conducted a series of triangle completion experiments in virtual reality, in which we varied the number of landmarks from an open steppe to a dense forest, thus going beyond the spatially simple environments that have been studied in the past. We analysed spatial behaviour at both the population and individual level with linear regression models and developed a computational model, based on maximum likelihood estimation (MLE), to infer the underlying combination of cues. Results: Overall homing performance was optimal in an environment containing three landmarks arranged around the goal location. With more than three landmarks, individual differences between participants in the use of cues are striking. For some, the addition of landmarks does not worsen their performance, whereas for others it seems to impair their use of landmark information. Discussion: It appears that navigation success in complex environments depends on the ability to identify the correct clearing around the goal location, suggesting that some participants may not be able to see the forest for the trees.

9.
Vaccine ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38839520

RESUMEN

The design of prophylactic and diagnostic tools specific to animal papillomaviruses is hampered by the difficulties of viral in vitro manipulation and by the scarce availability of dedicated biotechnological tools. This paper reports the production of Ovine Papillomavirus 3 (OaPV3)-based virus-like particles (OaPV3-VLPs) in the baculovirus system and their use to investigate host humoral immune response through the establishment of an indirect ELISA test., Polyclonal sera and monoclonal antibodies were generated against OaPV3-VLPs, and their isotype and reactivity were determined. Additionally, antibodies allowed OaPV3 detection in ovine squamous cell carcinoma (SCC) samples by immunohistochemistry. Results encourage the standardization of OaPV3-specific prophylactic and serological diagnostic tools, and open new perspectives for the study of host-viral interaction and SCC development.

10.
Ophthalmologie ; 121(5): 366-373, 2024 May.
Artículo en Alemán | MEDLINE | ID: mdl-38700760

RESUMEN

Orbital and periocular metastatic tumors used to be considered very rare; however, with the constant updating of drugs and detection methods for cancer treatment, new chemotherapies and radiation treatments are being used. The life expectancy of cancer patients has become longer and periocular metastases are becoming easier to detect. Our knowledge of this rare disease of metastases also needs to be updated. This article reviews the incidence, symptomatic presentation, clinical features, diagnostic approaches and current treatment of metastatic tumors of the orbit and ocular adnexa in these patients.


Asunto(s)
Neoplasias Orbitales , Humanos , Neoplasias Orbitales/secundario , Neoplasias Orbitales/terapia , Neoplasias de los Párpados/terapia , Neoplasias de los Párpados/patología , Neoplasias de los Párpados/epidemiología , Neoplasias de los Párpados/secundario , Neoplasias del Ojo/secundario , Neoplasias del Ojo/terapia , Neoplasias del Ojo/patología
11.
Sci Rep ; 14(1): 10055, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698058

RESUMEN

Endoscopic transgastric necrosectomy is crucial in the management of complications resulting from necrotizing pancreatitis. However, both real-time and visual-spatial information is lacking during the procedure, thereby jeopardizing a precise positioning of the endoscope. We conducted a proof-of-concept study with the aim of overcoming these technical difficulties. For this purpose, a three-dimensional (3D) phantom of a stomach and pancreatic necroses was 3D-printed based on spatial information from individual patient CT scans and subsequently integrated into a silicone torso. An electromagnetic (EM) sensor was adjusted inside the endoscope´s working channel. A software interface enabled real time visualization. The accuracy of this novel assistant system was tested ex vivo by four experienced interventional endoscopists who were supposed to reach seven targets inside the phantom in six different experimental runs of simulated endoscopic transgastric necrosectomy. Supported by endoscopic camera view combined with real-time 3D visualization, all endoscopists reached the targets with a targeting error ranging between 2.6 and 6.5 mm in a maximum of eight minutes. In summary, the EM tracking system might increase efficacy and safety of endoscopic transgastric necrosectomy at the experimental level by enhancing visualization. Yet, a broader feasibility study and further technical improvements are mandatory before aiming at implementation into clinical setting.


Asunto(s)
Fenómenos Electromagnéticos , Humanos , Fantasmas de Imagen , Estómago/cirugía , Estómago/diagnóstico por imagen , Pancreatitis Aguda Necrotizante/cirugía , Pancreatitis Aguda Necrotizante/diagnóstico por imagen , Endoscopía/métodos , Páncreas/cirugía , Impresión Tridimensional , Sistemas de Navegación Quirúrgica , Imagenología Tridimensional/métodos
12.
Open Forum Infect Dis ; 11(5): ofae242, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38770207

RESUMEN

In this retrospective cohort study, we evaluated risk factors for bacteremia in emergency department patients presenting with influenza-like symptoms during influenza epidemic seasons. In patients without fever, chronic heart or chronic liver disease, blood culture collection might be omitted.

13.
Endosc Int Open ; 12(5): E704-E714, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38812697

RESUMEN

Background and study aims Sedation of high-risk patients is a relevant issue in interventional endoscopy. This is especially because standard oximetric monitors display only hypoxia and not the preceding hypercapnia. Therefore, the question arises whether use of a nasal positive airway pressure (nPAP) system can decrease the rate of sedation-associated events. Patients and methods A randomized, prospective trial was conducted at University Hospital Ulm, including 98 consecutive patients, identified as high-risk (American Society of Anesthesiologists physical status ≥3) and scheduled for prolonged (>15 minutes) endoscopic procedures. Patients underwent 1:1 randomization to two groups: interventional (nPAP-Mask) and control (conventional oxygen supplementation). Levels of CO 2 were measured noninvasively by transcutaneous capnometry device. The primary outcome was incidence of hypoxia (SpO 2 <90% over 10 seconds) and incidence of severe hypoxia was incidence of SpO 2 <80% over 10 seconds. One of our secondary objectives was to determine if the nPAP-Mask could result in significant CO 2 retention among high-risk patients. Results Data analysis showed lower incidence of hypoxia in the interventional group (10/47 vs. 31/251) P <0.05. Episodes of severe hypoxia (SpO 2 <80% over 10 seconds) were more frequent in the control group (8/51) compared with the intervention group (2/47) P <0.05. There was no significant difference in ΔCO 2 levels in the interventional vs. control group (-6.01±7.66 vs. -7.35±8.59 mm Hg). Conclusions In high-risk patients use of a nasal positive airway pressure system could significantly lower risk of hypoxia, especially in prolonged procedures. The nPAP-Mask does not induce CO 2 retention when compared with conventional oxygen supplementation.

14.
Ophthalmologie ; 121(5): 352-365, 2024 May.
Artículo en Alemán | MEDLINE | ID: mdl-38649497

RESUMEN

BACKGROUND: Intraocular metastases arising from solid tumors are found in approximately 2% of patients with metastatic tumor diseases and are therefore more frequent than originally assumed. They often affect the uvea and are associated with a poor prognosis. Due to the difficult diagnosis and an inconsistent treatment regimen, ophthalmologists have a special responsibility here. OBJECTIVE: This article gives a summary of the various types of intraocular metastases with respect to clinical features, diagnostics, treatment and prognosis as well as recommendations for follow-up care. METHODS: A selective literature search was carried out on the topic of intraocular metastases using PubMed and Google Scholar. RESULTS: Intraocular metastases most frequently affect the uvea, specifically the choroid. In most cases the underlying disease is breast or lung cancer, but other rarer primary tumors have also been reported in the literature. Metastatic lesions can show very different morphological manifestations but can be distinguished based on the corresponding structure of manifestation in the eye and with the aid of targeted staging, thus providing valid information on the type of primary tumor. The treatment is partly experimental and usually depends on the primary tumor and leading symptoms of the patient. A differentiation between a curative or palliative treatment situation must always be made. CONCLUSION: Intraocular metastases are the most frequent intraocular tumor and are usually associated with a poor prognosis. Accurate diagnostics for finding the treatment as well as interdisciplinary collaboration and the presentation of the patient on the tumor board are essential.


Asunto(s)
Neoplasias del Ojo , Humanos , Neoplasias del Ojo/secundario , Neoplasias del Ojo/terapia , Neoplasias del Ojo/patología , Neoplasias del Ojo/diagnóstico , Pronóstico
15.
Ophthalmologie ; 121(5): 374-381, 2024 May.
Artículo en Alemán | MEDLINE | ID: mdl-38683363

RESUMEN

Metastases of malignant diseases are the most frequent tumors diagnosed in the human eye. They occur in approximately 5-10% of patients with solid tumors during the course of the disease. Their frequency is particularly high in patients with breast and lung cancer. Many highly sensitive periorbital tissues can be affected by the localization of the metastatic lesions and pose a number of clinical challenges. The main goal of the therapy of ocular metastases consists of the control of tumor growth (including the control of other possible manifestations throughout the body), the preservation of the affected eye and the minimization of potential iatrogenic damage to adjacent tissues. Overall, the purpose of this strategy is also to maintain the quality of life and especially the eyes and vision of the patient. Furthermore, pain should be avoided or at least alleviated. Of special importance is the differentiation between a curative or palliative situation. Patients with ocular metastases usually undergo systemic treatment appropriate for the underlying tumor entity, which is often accompanied by concomitant or sequential radiotherapy. In addition to classical chemotherapy, targeted treatment, treatment with monoclonal antibodies and antibody-drug conjugates as well as immunotherapy with checkpoint antibodies are currently available for many cancer types. This review article gives an overview of the currently available treatment options for patients with ocular metastases of solid tumors.


Asunto(s)
Neoplasias del Ojo , Estadificación de Neoplasias , Humanos , Neoplasias del Ojo/secundario , Neoplasias del Ojo/terapia , Neoplasias del Ojo/patología , Inmunoterapia/métodos , Terapia Combinada , Antineoplásicos/uso terapéutico
16.
Swiss Med Wkly ; 154: 3539, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38579330

RESUMEN

INTRODUCTION: During the first wave of the COVID-19 pandemic, increasingly strict restrictions were imposed on the activities of the Swiss population, with a peak from 21 March to 27 April 2020. Changes in trauma patterns during the pandemic and the lockdown have been described in various studies around the world, and highlight some particularly exposed groups of people. The objective of this study was to assess changes in trauma-related presentations to the emergency department (ED) during the first wave of the COVID-19 pandemic, as compared to the same period in the previous year, with a particular focus on vulnerable populations. MATERIALS AND METHODS: All trauma-related admissions to our ED in the first half of 2019 and 2020 were included. Patient demographics, trauma mechanism, affected body region, injury severity and discharge type were extracted from our hospital information system. Trauma subpopulations, such as interpersonal violence, self-inflicted trauma, geriatric trauma and sports-related trauma were analysed. RESULTS: A total of 5839 ED presentations were included in our study, of which 39.9% were female. Median age was 40 years (interquartile range: 27-60). In comparison to 2019, there was a 15.5% decrease in trauma-related ED presentations in the first half of 2020. This decrease was particularly marked in the 2-month March/April period, with a drop of 36.8%. In 2020, there was a reduction in injuries caused by falls of less than 3 metres or by mechanical force. There was a marked decrease in sports-related trauma and an increase in injuries related to pedal cycles. Geriatric trauma, self-harm and assault-related injuries remained stable. CONCLUSION: This study described changes in trauma patterns and highlighted populations at risk of trauma during the pandemic in Switzerland in the context of previous international studies.These results may contribute to resource management in a future pandemic.


Asunto(s)
COVID-19 , Centros Traumatológicos , Femenino , Humanos , Anciano , Adulto , Masculino , Estudios Retrospectivos , Suiza/epidemiología , COVID-19/epidemiología , Pandemias , Control de Enfermedades Transmisibles , Servicio de Urgencia en Hospital
17.
Artículo en Inglés | MEDLINE | ID: mdl-38563962

RESUMEN

PURPOSE: For optimal prehospital trauma care, it is essential to adequately recognize potential life-threatening injuries in order to correctly triage patients and to initiate life-saving measures. The aim of the present study was to determine the accuracy of prehospital diagnoses suspected by helicopter emergency medical services (HEMS). METHODS: This retrospective multicenter study included patients from the Swiss Trauma Registry with ISS ≥ 16 or AIS head ≥ 3 transported by Switzerland's largest HEMS and subsequently admitted to one of twelve Swiss trauma centers from 01/2020 to 12/2020. The primary outcome was the comparison of injuries suspected prehospital with the final diagnoses obtained at the hospital using the abbreviated injury scale (AIS) per body region. As secondary outcomes, prehospital interventions were compared to corresponding relevant diagnoses. RESULTS: Relevant head trauma was the most commonly injured body region and was identified in 96.3% (95% CI: 92.1%; 98.6%) of the cases prehospital. Relevant injuries to the chest, abdomen, and pelvis were also common but less often identified prehospital [62.7% (95% CI: 54.2%; 70.6%), 45.5% (95% CI: 30.4%; 61.2%), and 61.5% (95% CI: 44.6%; 76.6%)]. Overall, 7 of 95 (7.4%) patients with pneumothorax received a chest decompression and in 22 of 39 (56.4%) patients with an instable pelvic fracture a pelvic binder was applied prehospital. CONCLUSION: Approximately half of severe chest, abdominal, and pelvic diagnoses made in hospital went undetected in the challenging prehospital environment. This underlines the difficult circumstances faced by the rescue teams. Potentially life-saving interventions such as prehospital chest decompression and increased use of a pelvic binder were identified as potential improvements to prehospital care.

18.
Small ; : e2311250, 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38431938

RESUMEN

Ultrafast high-capacity lithium-ion batteries are extremely desirable for portable electronic devices, where Si is the most promising alternative to the conventional graphite anode due to its very high theoretical capacity. However, the low electronic conductivity and poor Li-diffusivity limit its rate capability. Moreover, high volume expansion/contraction upon Li-intake/uptake causes severe pulverization of the electrode, leading to drastic capacity fading. Here, interface and morphology-engineered amorphous Si matrix is being reported utilizing a few-layer vertical graphene (VG) buffer layer to retain high capacity at both slow and fast (dis)charging rates. The flexible mechanical support of VG due to the van-der-Waals interaction between the graphene layers, the weak adhesion between Si and graphene, and the highly porous geometry mitigated stress, while the three-dimensional mass loading enhanced specific capacity. Additionally, the high electronic conductivity of VG boosted rate-capability, resulting in a reversible gravimetric capacity of ≈1270 mAh g-1 (areal capacity of ≈37 µAh cm-2 ) even after 100 cycles at an ultrafast cycling rate of 20C, which provides a fascinating way for conductivity and stress management to obtain high-performance storage devices.

19.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38473729

RESUMEN

The toxicity of botulinum multi-domain neurotoxins (BoNTs) arises from a sequence of molecular events, in which the translocation of the catalytic domain through the membrane of a neurotransmitter vesicle plays a key role. A recent structural study of the translocation domain of BoNTs suggests that the interaction with the membrane is driven by the transition of an α helical switch towards a ß hairpin. Atomistic simulations in conjunction with the mesoscopic Twister model are used to investigate the consequences of this proposition for the toxin-membrane interaction. The conformational mobilities of the domain, as well as the effect of the membrane, implicitly examined by comparing water and water-ethanol solvents, lead to the conclusion that the transition of the switch modifies the internal dynamics and the effect of membrane hydrophobicity on the whole protein. The central two α helices, helix 1 and helix 2, forming two coiled-coil motifs, are analyzed using the Twister model, in which the initial deformation of the membrane by the protein is caused by the presence of local torques arising from asymmetric positions of hydrophobic residues. Different torque distributions are observed depending on the switch conformations and permit an origin for the mechanism opening the membrane to be proposed.


Asunto(s)
Toxinas Botulínicas , Humanos , Dominios Proteicos , Dominio Catalítico , Vesícula , Translocación Genética , Agua
20.
Curr Biol ; 34(6): 1364-1369.e2, 2024 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-38490201

RESUMEN

Though common among humans, social play by adults is an uncommon occurrence in most animals, even between parents and offspring.1,2,3 The most common explanation for why adult play is so rare is that its function and benefits are largely limited to development, so that social play has little value later in life.3,4,5,6 Here, we draw from 10 years of behavioral data collected by the Kibale Chimpanzee Project to consider an alternative hypothesis: that despite its benefits, adult play in non-humans is ecologically constrained by energy shortage or time limitations. We further hypothesized that, since they may be the only available partners for their young offspring, mother chimpanzees pay greater costs of play than other adults. Our analysis of nearly 4,000 adult play bouts revealed that adult chimpanzees played both among themselves and with immature partners. Social play was infrequent when diet quality was low but increased with the proportion of high-quality fruits in the diet. This suggests that adults engage in play facultatively when they have more energy and/or time to do so. However, when diet quality was low and most adult play fell to near zero, play persisted between mothers and offspring. Increased use of play by adult chimpanzees during periods of resource abundance suggests that play retains value as a social currency beyond development but that its costs constrain its use. At the same time, when ecological conditions constrain opportunities for young to play, play by mothers fills a critical role to promote healthy offspring development.


Asunto(s)
Hominidae , Pan troglodytes , Animales , Femenino , Humanos , Dieta , Conducta Animal , Madres , Conducta Social
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