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Abstract Neutron imaging has gained significant importance as a material characterisation technique and is particularly useful to visualise hydrogenous materials in objects opaque to other radiations. Fields of application include investigations of hydrogen in metals as well as metal corrosion, thanks to the fact that neutrons can penetrate metals better than e.g. X-rays and are highly sensitive to hydrogen. However, at interfaces refraction effects sometimes obscure the attenuation image, which is used for hydrogen quantification. Refraction, a differential phase effect, diverts the neutron beam away from the interface in the image leading to intensity gain and intensity loss regions, which are superimposed to the attenuation image, thus obscuring the interface region and hindering quantitative analyses of e.g. hydrogen content in the vicinity of the interface. For corresponding effects in X-ray imaging, a phase filter approach was developed and is generally based on transport-of-intensity considerations. Here, we compare such an approach, that has been adapted to neutrons, with another simulation-based assessment using the ray-tracing software McStas. The latter appears superior and promising for future extensions which enable fitting forward models via simulations in order to separate phase and attenuation effects and thus pave the way for overcoming quantitative limitations at refracting interfaces.

Abstract Intransitive gestures are expressive and symbolic, whereas pantomimes are object-related actions. These gestures convey different meanings depending on whether they are directed toward (TB) or away from the body (AB). TB gestures express mental states (intransitive) or hygiene/nutritional activities (pantomime), while AB gestures modify the behaviour of the observer (intransitive) or demonstrate tool use with an object (pantomime). A substantial body of literature suggests that females exhibit stronger social cue processing compared to males. Considering the social significance of gestures, this study aimed to explore the physiological gender differences in the observation of AB and TB gestures. Pupil dilation and High Frequency Heart Rate Variability (HF-HRV) were measured in 54 participants (27 female) while observing TB and AB gestures. The Interpersonal Reactivity Index (IRI) and the Vicarious Distress Questionnaire (VDQ) were used to assess social-emotional processes. Results showed greater pupil dilation in females for TB gestures, but no significant gender differences for HF-HRV. Males showed a significant correlation between increased pupil dilation to both TB and AB gestures and empathy levels (IRI). The support scale of the VDQ correlated significantly with TB gestures in males. These findings provide insight into the neurobiological basis of gender differences in perceiving social gestures.

Abstract Postoperative fluid overload (FO) after cardiac surgery is common and affects recovery. Predicting FO could help optimize fluid management. This post-hoc analysis of the HERACLES randomized controlled trial evaluated the predictive value of MR-proADM for FO post-cardiac surgery. MR-proADM levels were measured at four different timepoints in 33 patients undergoing elective cardiac surgery. Patients were divided into FO (> 5% weight gain) and no-FO at ICU discharge. The primary outcome was the predictive power of MR-proADM at ICU admission for FO at discharge. Secondary outcomes included the predictive value of MR-proADM for FO on day 6 post-surgery and changes over time. The association between MR-proADM and FO at ICU discharge or day 6 post-surgery was not significant (crude odds ratio (cOR): 4.3 (95% CI 0.5–40.9, p = 0.201) and cOR 1.1 (95% CI 0.04–28.3, p = 0.954)). MR-proADM levels over time did not differ significantly between patients with and without FO at ICU discharge (p = 0.803). MR-proADM at ICU admission was not associated with fluid overload at ICU discharge in patients undergoing elective cardiac surgery. MR-proADM levels over time were not significantly different between groups, although elevated levels were observed in patients with FO.

Abstract Within the brain, the connections between neurons are constantly changing in response to environmental stimuli. A prime environmental regulator of neuronal activity is diet, and previous work has highlighted changes in hypothalamic connections in response to diets high in dietary fat and elevated sucrose. We sought to determine if the change in hypothalamic neuronal connections was driven primarily by an elevation in dietary fat alone. Analysis was performed in both male and female animals. We measured Agouti-related peptide (AgRP) neuropeptide and Synaptophysin markers in the paraventricular nucleus of the hypothalamus (PVH) in response to an acute 48 h high fat diet challenge. Using two image analysis methods described in previous studies, an effect of a high fat diet on AgRP neuronal projections in the PVH of male or female mice was not identified. These results suggest that it may not be dietary fat alone that is responsible for the previously published alterations in hypothalamic connections. Future work should focus on deciphering the role of individual macronutrients on neuroanatomical and functional changes.

Study Design A prospective experimental study. Purpose This biomechanical in vitro study aimed to examine the extent to which the use of a rod persuader (RP) leads to additional mechanical stress on the screw–rod system and determine its influence on the bony anchoring of primary pedicle screws. Overview of Literature Degenerative spine diseases and deformities are the most common indications for the stabilization and fusion of spinal segments. The pedicle screw–rod system is considered the gold standard for dorsal stabilization, and an RP is also increasingly being considered to fit the spondylodesis material. Methods Ten lumbar spines from body donors were examined. Bisegmental dorsal spinal lumbar interbody fusion of the L3–L5 segments was performed using a pedicle screw–rod system (ROCCIA Multi-LIF Cage; Silony Medical, Germany). In group 1, the titanium rod was inserted without tension, whereas in group 2, the rod was attached to the pedicle screws at the L4 and L5 levels, creating a 5-mm gap. To attach the rod, the RP was used to press the rod into the pedicle screw. The rod was left in place for 30 minutes and then removed. Results The rod reduction technique significantly increased the mechanical load on the overall construct measured by strain gauges (p

Abstract As SARS-CoV-2 continues to spread worldwide, tractable primary airway cell models that recapitulate the cell-intrinsic response to arising viral variants are needed. Here we describe an adult stem cell-derived human airway organoid model overexpressing the ACE2 receptor (ACE2-OE) that supports robust viral replication while maintaining 3D architecture and cellular diversity of the airway epithelium. ACE2-OE organoids were infected with SARS-CoV-2 variants and subjected to single-cell RNA-sequencing. Interferon-lambda was upregulated in cells with low-level infection while the NF-kB inhibitor alpha gene (encoding IkBa) was consistently upregulated in infected cells, and its expression positively correlated with infection levels. Confocal microscopy showed more IkBa expression in infected than bystander cells, but found concurrent nuclear translocation of NF-kB that IkBa usually prevents. Overexpressing a nondegradable IkBa mutant reduced NF-kB translocation and increased viral infection. These data demonstrate the functionality of ACE2-OE organoids in SARS-CoV-2 research and underscore that the strength of the NF-kB feedback loop in infected cells controls viral replication.

Abstract Background The effectiveness of instructional videos as a stand-alone tool for the acquisition of practical skills is yet unknown because instructional videos are usually didactically embedded. Therefore, we evaluated the acquisition of the skill of a humeral intraosseous access via video in comparison to that of a self-study with an additional retention test. Methods After ethical approval, we conducted two consecutive studies. Both were designed as randomised controlled two-armed trials with last-year medical students as independent samples at our institutional simulation centre of a tertiary university hospital centre. In Study 1, we randomly assigned 78 participants to two groups: Vid-Self participants watched an instructional video as an intervention, followed by a test, and after seven days did a self-study as a control, followed by a test. Self-Vid ran through the trial in reverse order. In Study 2, we investigated the influence of the sequence of the two teaching methods on learning success in a new sample of 60 participants: Vid-Self watched an instructional video and directly afterward did the self-study followed by a test, whereas Self-Vid ran through that trial in reverse order. In Studies 1 and 2, the primary outcome was the score (worst score = 0, best score = 20) of the test after intervention and control. The secondary outcome in Study 1 was the change in score after seven days. Results Study 1: The Vid-Self (Participants n = 42) was superior to the Self-Vid (n = 36) (mean score 14.8 vs. 7.7, p

Abstract In advanced drug delivery, versatile liposomal formulations are commonly employed for safer and more accurate therapies. Here we report a method that allows a straightforward production of synthetic monodisperse (~ 100 μm) giant unilamellar vesicles (GUVs) using a microfluidic system. The stability analysis based on the microscopy imaging showed that at ambient conditions the produced GUVs had a half-life of 61 ± 2 h. However, it was observed that ~ 90% of the calcein dye that was loaded into GUVs was transported into a surrounding medium in 24 h, thus indicating that the GUVs may release these small dye molecules without distinguishable membrane disruption. We further demonstrated the feasibility of our method by loading GUVs with larger and very different cargo objects; small soluble fluorescent proteins and larger magnetic microparticles in a suspension. Compared to previously reported microfluidics-based production techniques, the obtained results indicate that our simplified method could be equally harnessed in creating GUVs with less cost, effort and time, which could further benefit studying closed membrane systems.

Abstract Next-generation sequencing (NGS) is emerging as a powerful tool for molecular diagnostics but remains limited by cumbersome and inefficient sample preparation. We present an innovative automated NGS library preparation system with a simplified mechanical design that exploits both macro- and microfluidic properties for optimizing heat transfer, reaction kinetics, mass transfer, fluid mechanics, adsorption–desorption rates, and molecular thermodynamics. Our approach introduces a unique two-cannula cylindrical capillary system connected to a programmable syringe pump and a Peltier heating element able to execute all steps with high efficiency. Automatic reagent movement, mixing, and magnetic bead-based washing with capillary-based thermal cycling (capillary-PCR) are completely integrated into a single platform. The manual 3-h library preparation process is reduced to less than 15 min of hands-on time via optimally pre-plated reagent plates, followed by less than 6 h of instrument run time during which no user interaction is required. We applied this method to two library preparation assays with different DNA fragmentation requirements (mechanical vs. enzymatic fragmentation), sufficiently limiting consumable use to one cartridge and one 384 well-plate per run. Our platform successfully prepared eight libraries in parallel, generating sequencing data for both human and Escherichia coli DNA libraries with negligible coverage bias compared to positive controls. All sequencing data from our libraries attained Phred (Q) scores > 30, mapping to reference genomes at 99% confidence. The method achieved final library concentrations and size distributions comparable with the conventional manual approach, demonstrating compatibility with downstream sequencing and subsequent data analysis. Our engineering design offers repeatability and consistency in the quality of sequence-able libraries, asserting the importance of mechanical design considerations that employ and optimize fundamental fluid mechanics and heat transfer properties. Furthermore in this work, we provide unique insights into the mechanisms of sample loss within NGS library preparation assays compared with automated adaptations and pinpoint areas in which the principles of thermodynamics, fluid mechanics, and heat transfer can improve future mechanical design iterations.

Abstract Background Point-of-care ultrasound (POCUS) is a critical diagnostic tool in various medical settings, yet its instruction in medical education is inconsistent. The Rapid Ultrasound for Shock and Hypotension (RUSH) protocol is a comprehensive diagnostic tool, but its complexity poses challenges for teaching and learning. This study evaluates the effectiveness of a single-day training in RUSH for medical students by assessing their performance in clinical scenarios. Methods In this prospective single-center observational proof-of-concept study, 16 medical students from Saarland University Medical Center underwent a single-day training in RUSH, followed by evaluations in clinical settings and on a high-fidelity simulator. Performance was assessed using a standardized scoring tool and time to complete the RUSH exam. Knowledge gain was measured with pre- and post-training written exams, and diagnostic performance was evaluated with an objective structured clinical examination (OSCE). Results Students demonstrated high performance in RUSH exam views across patients (median performance: 85–87%) and improved scanning times, although not statistically significant. They performed better on simulators than on live patients. Written exam scores significantly improved post-training, suggesting a gain in theoretical knowledge. However, more than a third of students could not complete the RUSH exam within five minutes on live patients. Conclusions Single-day RUSH training improved medical students’ theoretical knowledge and simulator performance but translating these skills to clinical settings proved challenging. The findings suggest that while short-term training can be beneficial, it may not suffice for clinical proficiency. This study underscores the need for structured and possibly longitudinal training programs to ensure skill retention and clinical applicability.

Abstract The thalamic reticular nucleus (TRN) is a brain region that influences vital neurobehavioral processes, including executive functioning and the generation of sleep rhythms. TRN dysfunction underlies hyperactivity, attention deficits, and sleep disturbances observed across various neurodevelopmental disorders. A specialized sarco-endoplasmic reticulum calcium (Ca2+) ATPase 2 (SERCA2)-dependent Ca2+ signaling network operates in the dendrites of TRN neurons to regulate their bursting activity. Phospholamban (PLN) is a prominent regulator of SERCA2 with an established role in myocardial Ca2 +-cycling. Our findings suggest that the role of PLN extends beyond the cardiovascular system to impact brain function. Specifically, we found PLN to be expressed in TRN neurons of the adult mouse brain, and utilized global constitutive and innovative conditional genetic knockout mouse models in concert with electroencephalography (EEG)-based somnography and the 5-choice serial reaction time task (5-CSRTT) to investigate the role of PLN in sleep and executive functioning, two complex behaviors that map onto thalamic reticular circuits. The results of the present study indicate that perturbed PLN function in the TRN results in aberrant TRN-dependent phenotypes in mice (i.e., hyperactivity, impulsivity and sleep deficits) and support a novel role for PLN as a critical regulator of SERCA2 in the TRN neurocircuitry.

Radio detection and ranging-based (radar) sensing offers unique opportunities for biomedical monitoring and can help overcome the limitations of currently established solutions. Due to its contactless and unobtrusive measurement principle, it can facilitate the longitudinal recording of human physiology and can help to bridge the gap from laboratory to real-world assessments. However, radar sensors typically yield complex and multidimensional data that are hard to interpret without domain expertise. Machine learning (ML) algorithms can be trained to extract meaningful information from radar data for medical experts, enhancing not only diagnostic capabilities but also contributing to advancements in disease prevention and treatment. However, until now, the two aspects of radar-based data acquisition and ML-based data processing have mostly been addressed individually and not as part of a holistic and end-to-end data analysis pipeline. For this reason, we present a tutorial on radar-based ML applications for biomedical monitoring that equally emphasizes both dimensions. We highlight the fundamentals of radar and ML theory, data acquisition and representation and outline categories of clinical relevance. Since the contactless and unobtrusive nature of radar-based sensing also raises novel ethical concerns regarding biomedical monitoring, we additionally present a discussion that carefully addresses the ethical aspects of this novel technology, particularly regarding data privacy, ownership, and potential biases in ML algorithms.

Black women continue to be disproportionally burdened by HIV. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention option, which is underused by Black women. While social network interventions (SNIs) have been widely researched and implemented among some groups vulnerable to HIV, little is known about social network characteristics among Black women. To learn more about the social networks of Black women vulnerable to HIV and their knowledge of and interest in PrEP, we conducted a cross-sectional survey among 109 Black women aged 18–45 years attending a family planning clinic in Chicago, Illinois. In our study, 44% of women reported that they were moderately to extremely concerned about HIV. Over half of participants (53%) had a small personal network size (i.e., less than two). No statistically significant associations between having larger network sizes and having previously heard of PrEP, having an interest in starting PrEP, or having good PrEP knowledge were detected. Open-ended responses revealed high levels of trust in network connections with matters related to sexual health. Additionally, nearly all (94%) of women reported that SNIs were a good idea to promote PrEP. Future network studies are needed to inform the development of effective intervention strategies for women.

Global warming of 1.5°C and even 2°C is likely to be exceeded during the 21st century. Climate change poses a worldwide threat and has direct and indirect effects on infectious diseases, on non-communicable diseases and on mental health. Not all people are equally able to protect themselves against the impacts of climate change; particularly populations that are vulnerable due to individual factors (children, older persons, those immunocompromised or with pre-existing conditions), social factors (the socially disadvantaged), or living and working conditions (e. g. people who work outdoors) are subject to an increased risk. Concepts such as One Health or Planetary Health provide a framework to frame both climate change itself and adaptation strategies or sets of actions for environmental human and animal health. Knowledge of climate change impacts has grown in recent years, and mitigation and adaptation strategies have been developed.

IntroductionTraumatic brain injury (TBI) accounts for the majority of Uganda's neurosurgical disease burden; however, invasive intracranial pressure (ICP) monitoring is infrequently used. Noninvasive monitoring could change the care of patients in such a setting through quick detection of elevated ICP.PurposeGiven the novelty of pupillometry in Uganda, this mixed methods study assessed the feasibility of pupillometry for noninvasive ICP monitoring for patients with TBI.MethodsTwenty-two healthcare workers in Kampala, Uganda received education on pupillometry, practiced using the device on healthy volunteers, and completed interviews discussing pupillometry and its implementation. Interviews were assessed with qualitative analysis, while quantitative analysis evaluated learning time, measurement time, and accuracy of measurements by participants compared to a trainer's measurements.ResultsMost participants (79%) reported a positive perception of pupillometry. Participants described the value of pupillometry in the care of patients during examination, monitoring, and intervention delivery. Commonly discussed concerns included pupillometry's cost, understanding, and maintenance needs. Perceived implementation challenges included device availability and contraindications for use. Participants suggested offering continued education and engaging hospital leadership as implementation strategies. During training, the average learning time was 13.5 minutes (IQR 3.5), and the measurement time was 50.6 seconds (IQR 11.8). Paired t-tests to evaluate accuracy showed no statistically significant difference in comparison measurements.ConclusionPupillometry was considered acceptable for noninvasive ICP monitoring of patients with TBI, and pupillometer use was shown to be feasible during training. However, key concerns would need to be addressed during implementation to aid device utilization.

Since the 19th century, underwater explosions have posed a significant threat to service members. While there have been attempts to establish injury criteria for the most vulnerable organs, namely the lungs, existing criteria are highly variable due to insufficient human data and the corresponding inability to understand the underlying injury mechanisms. This study presents an experimental characterization of isolated human lung dynamics during simulated exposure to underwater shock waves. We found that the large acoustic impedance at the surface of the lung severely attenuated transmission of the shock wave into the lungs. However, the shock wave initiated large bulk pressure-volume cycles that are distinct from the response of the solid organs under similar loading. These pressure-volume cycles are due to compression of the contained gas, which we modeled with the Rayleigh-Plesset equation. The extent of these lung dynamics was dependent on physical confinement, which in real underwater blast conditions is influenced by factors such as rib cage properties and donned equipment. Findings demonstrate a potential causal mechanism for implosion injuries, which has significant implications for the understanding of primary blast lung injury due to underwater blast exposures.

Cardiovascular diseases remain the leading global cause of mortality. Age is an important covariate whose effect is most easily investigated in a healthy cohort to properly distinguish the former from disease-related changes. Traditionally, most of such insights have been drawn from the analysis of electrocardiogram (ECG) feature changes in individuals as they age. However, these features, while informative, may potentially obscure underlying data relationships. In this paper we present the following contributions: (1) We employ a deep-learning model and a tree-based model to analyze ECG data from a robust dataset of healthy individuals across varying ages in both raw signals and ECG feature format. (2) We use explainable AI methods to identify the most discriminative ECG features across age groups.(3) Our analysis with tree-based classifiers reveals age-related declines in inferred breathing rates and identifies notably high SDANN values as indicative of elderly individuals, distinguishing them from younger adults. (4) Furthermore, the deep-learning model underscores the pivotal role of the P-wave in age predictions across all age groups, suggesting potential changes in the distribution of different P-wave types with age. These findings shed new light on age-related ECG changes, offering insights that transcend traditional feature-based approaches.

OBJETIVO: Presentar los resultados de nuestra experiencia durante el período 2010-2020 en pacientes con PR en recaída bioquímica utilizando RT como tratamiento de rescate, en los servicios de Radioterapia GURVE. MÉTODO: se seleccionaron 119 pacientes durante el periodo 2010-2020 que cumplieran con los criterios de inclusión, siendo tratados con RT como rescate. RESULTADOS: La mediana de edad fue de 66 años. La clasificación de riesgo, el Intermedio Desfavorable 38,7% de los pacientes, Intermedio Favorable 28,6%, Bajo riesgo 15,1%, Alto 14,3%, Muy Alto y No Precisa 1,7%. La técnica de irradiación más utilizada fue VMAT con el 94,1%, IMRT fue 5,0% con, y RTC3D 0,8%. El 83,2% de los pacientes no presentaron complicaciones GI agudas, el 12,6% presentó complicaciones Grado 1 y el 4,2% Grado 2. Las complicaciones GU el 68,1% (No presentaron), el 28,6% Grado 1 y 3,4%, Grado 2. La SG a los 5 años es de 98,5% +/- de 1,5%., y a los 10 años fue 92,4%, +/-7,6%. La SLRL a los 5 años fue 98,6%, +/- 1,4%; y a los 10 años 86,2%, +/- 6,1%; Sobrevida causa especifica (SCE) a los 5 años fue 100% y a los 10 años 97.3%, +/- 2.7%. La SLRD a los 5 años fue de 98,5%, +/- 1,5%, a los 10 años 74,4%, +/- 24,6%. CONCLUSIÓN: nuestros resultados demuestran que la administración de Radioterapia como tratamiento de rescate en pacientes post PR en recaída bioquímica es un tratamiento seguro y efectivo en el CL de la enfermedad, SG y SCE.

Public deliberation, or deliberative democracy, is a method used to elicit informed perspectives and justifiable solutions to ethically fraught or contentious issues that affect multiple stakeholder groups with conflicting interests. Deliberative events bring together stakeholders (deliberants) who are provided with empirical evidence on the central issue or concern and then asked to discuss the evidence, consider the issue from a societal perspective, and collectively work toward a justifiable resolution. There is increasing interest in this method, which warrants clear guidance for evaluating the quality of its use in research. Most of the existing literature on measuring deliberation quality emphasizes the quality of deliberants’ inputs (eg, engagement and evidence of compromise) during deliberative sessions. Fewer researchers have framed quality in terms of facilitator inputs, and these researchers tend to examine inputs that are consistent with generic group processes. The theory, process, and purpose of public deliberation, however, are distinct from those of focus groups or other group-based discussions and warrant a mechanism for measuring quality in terms of facilitator fidelity to the principles and processes of deliberative democracy. In our public deliberation on ethical conflicts in minor consent for biomedical HIV prevention research, we assessed facilitator fidelity to these principles and processes because we believe that such assessments serve as a component of a comprehensive evaluation of overall deliberation quality. We examined verbatim facilitator remarks in the deliberation transcripts and determined whether they aligned with the 6 principles of public deliberation: equal participation, respect for the opinions of others, adoption of a societal perspective, reasoned justification of ideas, expression of diverse opinions, and compromise or movement toward consensus. In this tutorial, we describe the development of a blueprint to guide researchers in assessing facilitator fidelity, share 3 templates that will assist them in the task, and describe the results of our assessment of facilitator fidelity in 1 of the 4 sites in which we conducted deliberations.

The incorporation of lipid droplets and further characterization of matrices within dairy products may be possible using such adjacent particles as protein complexes/lipids. Among the range of varied emulsions and their functionalities, great attention has recently focused on the fabrication of high internal phase types. Feasibly, stable alternatives structured with health-beneficial lipids like those derived from plants could replace saturated fatty acids. As a fat replacement strategy, the fate of incorporated HIPE would require some adjustments either with storage stability and/or structural feat for the food matrix. Therefore, the replacement of milk fat by rapeseed oil stabilised emulsion in commercial yogurt was investigated. This involved 25%, 50% and 75% rapeseed oil respectively assigned as low (LIPE), medium (MIPE), and high internal phase emulsion (HIPE). Specifically, emulsions were examined by droplet size, encapsulation, pH, zeta potential, phase separation, and rheology. The fat free yogurt supplemented by HIPE were examined by droplet size, zeta potential, pH, color, sensory, texture and microbiological aspects against positive (regular milk fat) and negative (fat free) yogurt controls. Results showed increasing rapeseed oil contents would form smaller droplet-like emulsions. Within the yogurt matrix however, incorporating HIPE would seemingly reduce oil droplet size without much compromise to bacterial viability, sensory, or texture. Overall, this simple method of lipid alternation shows promise in dairy products.

El Hemangioblastoma (HB) es un tumor benigno del sistema nervioso central, en algunos casos, su crecimiento hace que se comporte de manera agresiva debido al efecto de masa que ejerce sobre estructuras cercanas; puede presentarse de manera esporádica o como asociados a la enfermedad de Von Hippel Lindau (VHL); el tratamiento de preferencia para los HB esporádicos es la resección quirúrgica, sin embargo, para los asociados a VHL, la radioterapia ha demostrado ser un tratamiento efectivo. En las últimas décadas con los avances en las nuevas técnicas de radioterapia, como la radioterapia estereotáxica craneal; ha sido posible aumentar la dosis dirigida a estas lesiones, siendo un tratamiento eficaz, con tasas de control de enfermedad significativas y con toxicidad aceptable, por lo que es relevante conocer y aplicar este tipo de tratamientos. Es por ello que el realizar una revisión narrativa acerca de este tema, en el Centro médico Docente La Trinidad, nos brindan un conocimiento adecuado y actualizado, sobre el tratamiento eficaz y seguro de esta patología, permitiendo el uso de esta modalidad en nuestro país, en pro del bien de nuestros pacientes.

El cáncer de páncreas es una enfermedad donde la mayoría de los pacientes se encuentran en estadios irresecables desde su diagnóstico. La radioterapia y la quimioterapia han demostrado ser parte importante en el tratamiento de los pacientes con cáncer de páncreas. Con el advenimiento de las nuevas técnicas de radioterapia ha sido posible aumentar la dosis dirigida a la lesión, respetando las tolerancias de los órganos adyacentes a la misma. Está descrito que el aumento la dosis de radiación por fracción aumenta a su vez la dosis biológicamente efectiva (BED) permitiendo que se realice el tratamiento en menos tiempo y a su vez escalando la dosis total que recibe el paciente. Ésta es la base del hipofraccionamiento y de la radioterapia estereotáxica las cuales poseen un papel cada vez mayor en el tratamiento de este grupo de pacientes debido a la mejor respuesta que presenta este tipo de tumores al aumentar la dosis de radiación. El desarrollo de una revisión narrativa sobre el escalamiento de dosis con radioterapia externa en cáncer de páncreas, nos permite conocer las técnicas y fraccionamientos que se están utilizando, motivando al desarrollo y uso de dichas herramientas en beneficio del paciente en nuestro país.

El cáncer de próstata es la neoplasia no cutánea más común en hombres, y al diagnosticarlo en una etapa localizada, los pacientes presentan una amplia variedad de posibles opciones terapéuticas, que van desde observación, hasta tratamientos multimodales que incluyen radioterapia, prostatectomía radical, y bloqueo androgénico total, según sea el caso. Cuando el diagnóstico se hace en estadio IV, hasta hace un par de años, la radioterapia se utilizaba como un tratamiento paliativo, solo para aliviar el dolor y evitar fracturas patológicas en huesos que soportan carga. En la actualidad se ha incorporado un nuevo concepto, el de la enfermedad oligometastásica, como un estado intermedio entre la enfermedad localizada y la sistémica o metastásica, en el que el tratamiento del cáncer primario y las lesiones secundarias tiene un potencial curativo. La radioterapia estereotáctica extracraneal es una modalidad novedosa de tratamiento, con un gran potencial en el manejo de las enfermedades neoplásicas, especialmente en las oligometastásicas, ya que se puede administrar dosis altas de radiación de una manera rápida, segura, efectiva, respetando las tolerancias de los órganos adyacentes a nuestro objetivo. El desarrollo de una revisión narrativa sobre la radioterapia estereotáctica extracraneal como tratamiento del cáncer de próstata oligometastásico, nos permite conocer la técnica, fraccionamientos y resultados, para motivar el desarrollo y uso de estas herramientas y así mejorar el pronóstico de este grupo de pacientes y difundir su aplicación en Venezuela.

Introducción: La enfermedad cardíaca radioinducida (ECIR) afecta a pacientes con cáncer de mama (CDM) y se asocia con la dosis absorbida por el corazón y la arteria descendente anterior (ADA). Es importante cumplir las dosis de tolerancia para limitar la cardiotoxicidad al emplear los recientes esquemas de radioterapia hipofraccionada (RTHF) y radioterapia ultrahipofraccionada (RTUF), ya que su impacto en la salud cardiovascular es desconocido. Objetivo: El objetivo de este estudio observacional analítico, retrospectivo y longitudinal fue estimar el riesgo de ECIR mediante la evaluación dosimétrica del corazón y la ADA en pacientes con CDM tratadas con RTHF y RTUF (2019-2023). Métodos: Se revisaron 440 historias clínicas, se evaluaron los factores de riesgo para ECIR y las técnicas utilizadas considerando la dosis al emplear RTHF y RTUF. Resultados: 51 mujeres entre 41-88 años formaron la muestra, 52,94% recibió RTHF y 47,06% recibió RTUF; mediante RTC3D:84,31%, IMRT:7,74% y VMAT:7,74%, con una mediana de seguimiento de 18,96 meses. En RTHF para el corazón el 100% cumplió V16≤5%, para la ADA, 92,59% cumplió V13,4≤10%. En RTUF para el corazón se aplicaron dos restricciones, 87,50% cumplió V6,5≤5% y 62,50% cumplió V1,3≤25%; para la ADA, 83,33% cumplió V9,2≤10%; el cumplimiento de las tolerancias fue mayor con RTC3D, seguido de IMRT y VMAT. Ninguna paciente presentó complicaciones cardiovasculares y todas viven sin recaídas. Conclusión: Es necesario delimitar la ADA desde el inicio de la planificación del tratamiento en CDM para un adecuado cumplimiento de las dosis de tolerancia, con la finalidad de reducir el riesgo de ECIR.

Las metástasis cerebrales son las neoplasias más frecuentes del sistema nervioso central en la edad adulta, representando el 50% de las neoplasias intracraneales. El enfoque primario de tratamiento incluye cirugía, radioterapia estereotáxica intracraneal y radioterapia holocraneal. En la actualidad la radioterapia holocraneal adyuvante y definitiva, consiste en la irradiación a todo el encéfalo y la radioterapia estereotáxica intracraneal postoperatoria y definitiva, permite la administración de alta dosis de radiación a la lesión tumoral, utilizando técnicas avanzadas de planificación, en 1 – 5 fracciones, reduciendo significativamente el riesgo de recurrencia local. Aunque está indicada en pacientes con un número limitado de metástasis cerebrales, es una modalidad utilizada en los últimos años, como medida de rescate para pacientes con esta entidad, sin embargo, no existe suficiente evidencia que lo sustente, es por ello que el enfoque de esta revisión va dirigido a recopilar más información sobre el beneficio clínico, así como algunas de las variables que pueden incidir en la supervivencia de los pacientes con reirradiación del SNC para el control de metástasis cerebrales recurrentes. En la radioterapia estereotáxica intracraneal de rescate, una de las complicaciones más temidas en los pacientes que ameritan reirradiación es la radionecrosis, sobre todo en aquellas lesiones que se presentan en el lugar del tratamiento previo, por los múltiples efectos adversos que esto puede generar. Darle sustento a esta modalidad de tratamiento permite justificar su aplicación en nuestro centro de desarrollo profesional y darle un aporte a su uso en otras instituciones nacionales e internacionales.

Efficacy data on two malaria vaccines, RTS,S and R21, targeting Plasmodium falciparum circumsporozoite protein (PfCSP), are encouraging. Efficacy may be improved by induction of additional antibodies to neutralizing epitopes outside of the central immunodominant repeat domain of PfCSP. We designed four rPfCSP-based vaccines in an effort to improve the diversity of the antibody response. We also evaluated P. falciparum merozoite surface protein 8 (PfMSP8) as a malaria-specific carrier protein as an alternative to hepatitis B surface antigen. We measured the magnitude, specificity, subclass, avidity, durability, and efficacy of vaccine-induced antibodies in outbred CD1 mice. In comparison to N-terminal- or C-terminal-focused constructs, immunization with near full-length vaccines, rPfCSP (#1) or the chimeric rPfCSP/8 (#2), markedly increased the breadth of B cell epitopes recognized covering the N-terminal domain, junctional region, and central repeat. Both rPfCSP (#1) and rPfCSP/8 (#2) also elicited a high proportion of antibodies to conformation-dependent epitopes in the C-terminus of PfCSP. Fusion of PfCSP to PfMSP8 shifted the specificity of the T cell response away from PfCSP toward PfMSP8 epitopes. Challenge studies with transgenic Plasmodium yoelii sporozoites expressing PfCSP demonstrated high and consistent sterile protection following rPfCSP/8 (#2) immunization. Of note, antibodies to conformational C-terminal epitopes were not required for protection. These results indicate that inclusion of the N-terminal domain of PfCSP can drive responses to protective, repeat, and non-repeat B cell epitopes and that PfMSP8 is an effective carrier for induction of high-titer, durable anti-PfCSP antibodies.

Abstract Background Acute kidney injury (AKI) occurs frequently in critically ill patients and is associated with adverse outcomes. Cellular mechanisms underlying AKI and kidney cell responses to injury remain incompletely understood. Methods We performed single-nuclei transcriptomics, bulk transcriptomics, molecular imaging studies, and conventional histology on kidney tissues from 8 individuals with severe AKI (stage 2 or 3 according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria). Specimens were obtained within 1–2 h after individuals had succumbed to critical illness associated with respiratory infections, with 4 of 8 individuals diagnosed with COVID-19. Control kidney tissues were obtained post-mortem or after nephrectomy from individuals without AKI. Results High-depth single cell-resolved gene expression data of human kidneys affected by AKI revealed enrichment of novel injury-associated cell states within the major cell types of the tubular epithelium, in particular in proximal tubules, thick ascending limbs, and distal convoluted tubules. Four distinct, hierarchically interconnected injured cell states were distinguishable and characterized by transcriptome patterns associated with oxidative stress, hypoxia, interferon response, and epithelial-to-mesenchymal transition, respectively. Transcriptome differences between individuals with AKI were driven primarily by the cell type-specific abundance of these four injury subtypes rather than by private molecular responses. AKI-associated changes in gene expression between individuals with and without COVID-19 were similar. Conclusions The study provides an extensive resource of the cell type-specific transcriptomic responses associated with critical illness-associated AKI in humans, highlighting recurrent disease-associated signatures and inter-individual heterogeneity. Personalized molecular disease assessment in human AKI may foster the development of tailored therapies.

The implantation of a transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis improves pathologic blood flow through the aortic valve, but still alters hemodynamics in comparison to a healthy native aortic valve. The hemodynamic characteristics of TAVR are associated with hypo-attenuating leaflet thickening and prosthetic leaflet thrombosis, which may reduce the durability of TAVR. For this reason we developed a numerical model to identify pro-thrombotic regions of TAVR based on the velocity field. In silico models have already been proven to be an effective tool for device optimization in other medical device applications. However, when using an in silico model, it is important to validate the model assumptions with experimental data or analytical solutions to confirm the accuracy of the model. In this study, we present an approach to validate a complex numerical Fluid Structure Interaction (FSI) model used to simulate leaflet kinematics and flow in the vicinity of a TAVR. Based on the recommendation of ISO 5840 (2021), a combined validation of the kinematic and fluid dynamic parameters was performed for this purpose. The leaflet kinematic was investigated via high-speed recordings and evaluated based on the Geometric Orifice Area (GOA). The velocity field of the TAVR was determined experimentally using Particle Image Velocimetry (PIV). The evaluation of the GOA showed a good agreement of the in silico model with the in vitro data for the systolic duration. The occurring velocities were qualitatively compared during peak systole for three planes and showed similar flow characteristics. The maximum velocity was 1.1 m/s in the in vitro and in silico model. Based on the results, it can be assumed that the numerical FSI model of the TAVR can be used for thrombosis risk assessment.

Abstract Zinc inhibits intestinal copper uptake, an effect utilized for treating Wilson’s disease (WD). We used copper-64 (64Cu) PET/CT to examine how much four weeks of treatment with different zinc regimens reduced the hepatic 64Cu content after oral 64Cu administration and test if alternative regimens were noninferior to the standard regimen of zinc acetate 50 mg × 3 daily. Forty healthy persons were randomized to four different zinc protocols. The WD standard treatment zinc acetate 50 mg × 3 reduced the hepatic 64Cu content from 26.9 ± 7.5% to 13.3 ± 5.6% of the administered 64Cu. Zinc gluconate 50 mg × 3 was noninferior (P = 0.02) (35.8 ± 9.0% to 17.4 ± 7.5%). Zinc acetate 150 mg × 1 (33.1 ± 9.9% to 17.4 ± 7.5%) and zinc gluconate 150 mg × 1 (28.1 ± 6.7% to 22.0 ± 6.7%) were less effective. These effects were intra- and inter-individually highly variable, and 14% had no effect of any zinc regimen, which may explain disparities in zinc treatment efficacy in WD patients.

Background: Long COVID is a growing condition among individuals, with fatigue being one of the main symptoms experienced. Energy Management Education (EME) is a structured occupational therapy group intervention that aims to reduce the impact of fatigue in daily life. Methods: This study utilized focus groups to explore the experiences of individuals with post-COVID-related fatigue who participated in the EME program. Six participants engaged in discussions about the program immediately after its completion and again two months later. Additionally, five occupational therapists shared their experiences. Results: Former participants reported implementing strategies learned in the program to manage their condition effectively. They emphasized the importance of understanding fatigue and found the support provided by the peer group valuable. Occupational therapists highlighted the unique challenges faced by individuals with post-COVID-related fatigue compared to other populations with similar fatigue symptoms. Furthermore, insights were obtained regarding the ways individuals live and cope with post-COVID-related fatigue. Conclusion: EME participants were involved in a dynamic and complex occupational therapy process and were experiencing a slow change towards having more control over their daily routines. The study gathered valuable feedback and suggestions from participants and occupational therapists which can be used to optimize the EME program.

Abstract Thiosulfate sulfurtransferase (TST, EC 2.8.1.1), also known as Rhodanese, was initially discovered as a cyanide detoxification enzyme. However, it was recently also found to be a genetic predictor of resistance to obesity-related type 2 diabetes. Diabetes type 2 is characterized by progressive loss of adequate β-cell insulin secretion and onset of insulin resistance with increased insulin demand, which contributes to the development of hyperglycemia. Diabetic complications have been replicated in adult hyperglycemic zebrafish, including retinopathy, nephropathy, impaired wound healing, metabolic memory, and sensory axonal degeneration. Pancreatic and duodenal homeobox 1 (Pdx1) is a key component in pancreas development and mature beta cell function and survival. Pdx1 knockdown or knockout in zebrafish induces hyperglycemia and is accompanied by organ alterations similar to clinical diabetic retinopathy and diabetic nephropathy. Here we show that pdx1-knockdown zebrafish embryos and larvae survived after incubation with thiosulfate and no obvious morphological alterations were observed. Importantly, incubation with hTST and thiosulfate rescued the hyperglycemic phenotype in pdx1-knockdown zebrafish pronephros. Activation of the mitochondrial TST pathway might be a promising option for therapeutic intervention in diabetes and its organ complications.

Abstract We report a method for the phase reconstruction of an ultrashort laser pulse based on the deep learning of the nonlinear spectral changes induce by self-phase modulation. The neural networks were trained on simulated pulses with random initial phases and spectra, with pulse durations between 8.5 and 65 fs. The reconstruction is valid with moderate spectral resolution, and is robust to noise. The method was validated on experimental data produced from an ultrafast laser system, where near real-time phase reconstructions were performed. This method can be used in systems with known linear and nonlinear responses, even when the fluence is not known, making this method ideal for difficult to measure beams such as the high energy, large aperture beams produced in petawatt systems.

Abstract Background In individuals suffering from a rare disease the diagnostic process and the confirmation of a final diagnosis often extends over many years. Factors contributing to delayed diagnosis include health care professionals' limited knowledge of rare diseases and frequent (co-)occurrence of mental disorders that may complicate and delay the diagnostic process. The ZSE-DUO study aims to assess the benefits of a combination of a physician focusing on somatic aspects with a mental health expert working side by side as a tandem in the diagnostic process. Study design This multi-center, prospective controlled study has a two-phase cohort design. Methods Two cohorts of 682 patients each are sequentially recruited from 11 university-based German Centers for Rare Diseases (CRD): the standard care cohort (control, somatic expertise only) and the innovative care cohort (experimental, combined somatic and mental health expertise). Individuals aged 12 years and older presenting with symptoms and signs which are not explained by current diagnoses will be included. Data will be collected prior to the first visit to the CRD’s outpatient clinic (T0), at the first visit (T1) and 12 months thereafter (T2). Outcomes Primary outcome is the percentage of patients with one or more confirmed diagnoses covering the symptomatic spectrum presented. Sample size is calculated to detect a 10 percent increase from 30% in standard care to 40% in the innovative dual expert cohort. Secondary outcomes are (a) time to diagnosis/diagnoses explaining the symptomatology; (b) proportion of patients successfully referred from CRD to standard care; (c) costs of diagnosis including incremental cost effectiveness ratios; (d) predictive value of screening instruments administered at T0 to identify patients with mental disorders; (e) patients’ quality of life and evaluation of care; and f) physicians’ satisfaction with the innovative care approach. Conclusions This is the first multi-center study to investigate the effects of a mental health specialist working in tandem with a somatic expert physician in CRDs. If this innovative approach proves successful, it will be made available on a larger scale nationally and promoted internationally. In the best case, ZSE-DUO can significantly shorten the time to diagnosis for a suspected rare disease. Trial registration ClinicalTrials.gov; Identifier: NCT03563677; First posted: June 20, 2018, https://clinicaltrials.gov/ct2/show/NCT03563677 .

Abstract Climate change and disturbance can alter invasion success of clonal plants by differentially affecting the clonal traits influencing their establishment as young plants. Clonal traits related to the vegetative reproduction of native Pascopyrum smithii and non-native Bromus inermis grass seedlings were evaluated under altered precipitation frequencies and a single grazing event. Pascopyrum smithii maintained similar vegetative reproduction under three simulated precipitation frequencies whereas B. inermis vegetative reproduction declined as precipitation became more intermittent. Vegetative reproduction of the non-native B. inermis was greater than the native P. smithii under all simulated precipitation frequencies except the most intermittent scenario. A single grazing event did not affect either species’ response to intra-annual precipitation variability but did slightly reduce their clonal growth and increase their bud dormancy. In young plants, clonal traits of the invasive grass favored its superior expansion and population growth compared to the native grass except under the most severe climate change scenario. Grassland restoration using native P. smithii seeds would be successful in most years due to its resilient clonal growth in a changing climate. Clonal infrastructure development in young plants is critical to clonal plant establishment and persistence in a changing climate and under disturbed conditions.

BackgroundInflammatory bowel diseases (IBDs) with the subtypes ulcerative colitis (UC) and Crohn disease (CD), are chronic autoimmune inflammatory disorders of the gastrointestinal tract. Cytokines are associated with the development and progression in pediatric IBD. We measured cytokine levels in pediatric IBD patients to assess their potential function as biomarkers in disease assessment.MethodIn this prospective cohort study, we enrolled 33 children with IBD. All patients were in stable remission for 3 months on enrollment. Patients who developed a relapse within six months after enrollment were classified as relapsers. Blood sampling was performed at enrolment and for relapsers in relapse and post-relapse. Serum concentrations of 14 cytokines, chemokines and growth factors (IL-1α, IL-1β, IL-6, IL-12p40, IP-10, TNF-α, IFN-γ, IL-10, IL-8, MIP-1α, MCP-1, MCP-3, G-CSF, GM-CSF) were measured simultaneously using multiplex bead-based sandwich immunoassay on Luminex 100 system.ResultsMCP-1 was significantly higher in CD patients compared to UC patients at each disease stage: stable remission (PConclusionMCP-1 showed potential as a diagnostic biomarker in CD patients independent of disease activity as it was able to discriminate between subtypes of pediatric IBD. In UC patients, G-CSF was significantly elevated in relapsers indicating its use and role as a potential prognostic biomarker.

Introduction Gastric cancer remains the fourth leading cause of cancer-related death in Europe, while the proportion of adenocarcinomas of the esophagogastric junction has risen by more than one third over recent years. In 2018, 14,700 new cases of gastric cancer were estimated in Germany, while the 5-year relative survival rate is reported to be 33% for women and 30% for men; in the USA almost the same rate was reported, with 31% 5-year survival. Material and methods Between 2001 and 2014, 590 patients with a diagnosis of gastric cancer underwent surgery in our institution, including 120 Siewert type II/III carcinomas of the esophagogastric junction. All patients underwent distal resection of the stomach, gastrectomy or total gastrectomy combined with transhiatal distal esophageal resection. All operations included D2-D3 lymph node dissection (LND). Data were recorded by the cancer registry of the department of surgery and analyzed retrospectively. Results The patients were classified according to the TNM (UICC 2010) and Lauren classification. 29% of the patients underwent primary surgery and 31% received neoadjuvant therapy. The median number of harvested lymph nodes was 33 for patients diagnosed with gastric cancer, and 29 for esophagogastric adenocarcinomas, respectively. The anastomotic leak rate was 3%. In this study, the 5-year overall survival rate was 51% concerning gastric carcinomas, 44% for Siewert type II and 47% for Siewert III cancers of the esophagogastric junction. Conclusions Increased survival with low complication rates were achieved after individualized and multimodal treatment concepts combined with consistently applied extended lymphadenectomy.

Abstract A clinical implementation of cell-based bone regeneration in combination with scaffold materials requires the development of efficient, controlled and reproducible seeding procedures and a tailor-made bioreactor design. A perfusion system for efficient, homogeneous, and rapid seeding with human adipogenic stem cells in bone substitute scaffolds was designed. Variants concerning medium inlet and outlet port geometry, i.e. cylindrical or conical diffuser, cell concentration, perfusion mode and perfusion rates were simulated in silico. Cell distribution during perfusion was monitored by dynamic [18F]FDG micro-PET/CT and validated by laser scanning microscopy with three-dimensional image reconstruction. By iterative feedback of the in silico and in vitro experiments, the homogeneity of cell distribution throughout the scaffold was optimized with adjustment of flow rates, cell density and perfusion properties. Finally, a bioreactor with a conical diffusor geometry was developed, that allows a homogeneous cell seeding (hoover coefficient: 0.24) in less than 60 min with an oscillating perfusion mode. During this short period of time, the cells initially adhere within the entire scaffold and stay viable. After two weeks, the formation of several cell layers was observed, which was associated with an osteogenic differentiation process. This newly designed bioreactor may be considered as a prototype for chairside application.

Mitral regurgitation (MR) is the second most frequent indication for heart valve surgery and catheter interventions. According to European and US-American guidelines, transcatheter mitral valve repair in general and transcatheter edge-to-edge repair (TEER) in particular may be considered as a treatment option for selected high-risk patients. However, the biomechanical impact of TEERdevices on the mitral valve (MV) has not yet been fully understood. To address this problem, a 3D-Fluid-Structure Interaction (FSI) framework utilizing non-linear Finite Element Analysis (FEA) for the MV apparatus and Smoothed Particle Hydrodynamics (SPH) for the pulsatile fluid flow was developed and validated against in vitro data. An artificial MV-model (MVM) with a prolapse in the A2-P2 region and a custom-made TEER device implanted in the A2-P2 region were used for the in vitro investigations. In accordance with ISO 5910, projected mitral orifice areas (PMOA), flow rates as well as atrial and ventricular pressures were measured under pulsatile flow conditions before and after TEER device implantation. For the FSI-model, the MVM geometry was reconstructed by means of microcomputed tomography in a quasi-stress-free configuration. Quasi-static tensile test data was utilized for the development of linear- and hyperelastic material models of the chordae tendineae and leaflets, respectively. The fluid flow was modelled assuming an incompressible, homogenous Newtonian behaviour. Time-varying in vitro transmitral pressure loading was applied as a boundary condition. In vitro investigations show that TEER device implantation in the A2-P2 region effectively reduces the regurgitation fraction (RF) from 55 % to 13 %. Moreover, the comparison of experimental and numerical data yields a deviation of 2.09 % for the RF and a deviation of 0.40 % and 6.47 % for the maximum and minimum PMOA, respectively. The developed FSI-framework is in good agreement with in vitro data and is therefore applicable for the characterization of the biomechanical impact of different TEER devices under pulsatile flow conditions.

Bioresorbable nanofiber nonwovens with their fascinating properties provide a wide range of potential biomedical applications. Modification of the material enables the adjustment of mechanical and biological characteristics depending on the desired application. Due to the nanosized fiber network, post-production structuring is very challenging. Within this study, we use femtosecond laser technology for structuring permeable and resorbable electrospun poly-L-lactide (PLLA) membranes. We show that this post-production process can be used without disturbing the fiber network near the structured areas. Furthermore, the modification of the water permeability and mechanical characteristics due to the laser structuring was investigated. The results prove femtosecond laser technology to be a promising method for the adjustment of the membrane properties and which in consequence can help to optimize cell adhesion, enable revascularization and open up applications of nanofiber membranes in personalized medicine.

Abstract A non-invasive and sensitive blood test has long been a goal for early stage disease diagnosis and treatment for Alzheimer’s disease (AD) and other proteinopathy diseases. We previously reported that preeclampsia (PE), a severe pregnancy complication, is another proteinopathy disorder with impaired autophagy. We hypothesized that induced autophagy deficiency would promote accumulation of pathologic protein aggregates. Here, we describe a novel, sensitive assay that detects serum protein aggregates from patients with PE (n = 33 early onset and 33 late onset) and gestational age-matched controls (n = 77) as well as AD in both dementia and prodromal mild cognitive impairment (MCI, n = 24) stages with age-matched controls (n = 19). The assay employs exposure of genetically engineered, autophagy-deficient human trophoblasts (ADTs) to serum from patients. The aggregated protein complexes and their individual components, including transthyretin, amyloid β-42, α-synuclein, and phosphorylated tau231, can be detected and quantified by co-staining with ProteoStat, a rotor dye with affinity to aggregated proteins, and respective antibodies. Detection of protein aggregates in ADTs was not dependent on transcriptional upregulation of these biomarkers. The ROC curve analysis validated the robustness of the assay for its specificity and sensitivity (PE; AUC: 1, CI: 0.949–1.00; AD; AUC: 0.986, CI: 0.832–1.00). In conclusion, we have developed a novel, noninvasive diagnostic and predictive assay for AD, MCI and PE.

Abstract Cilia are protrusions of the cell surface and composed of hundreds of proteins many of which are evolutionary and functionally well conserved. In cells assembling motile cilia the expression of numerous ciliary components is under the control of the transcription factor FOXJ1. Here, we analyse the evolutionary conserved FOXJ1 target CFAP161 in Xenopus and mouse. In both species Cfap161 expression correlates with the presence of motile cilia and depends on FOXJ1. Tagged CFAP161 localises to the basal bodies of multiciliated cells of the Xenopus larval epidermis, and in mice CFAP161 protein localises to the axoneme. Surprisingly, disruption of the Cfap161 gene in both species did not lead to motile cilia-related phenotypes, which contrasts with the conserved expression in cells carrying motile cilia and high sequence conservation. In mice mutation of Cfap161 stabilised the mutant mRNA making genetic compensation triggered by mRNA decay unlikely. However, genes related to microtubules and cilia, microtubule motor activity and inner dyneins were dysregulated, which might buffer the Cfap161 mutation.

Abstract The novel SARS-CoV-2 virus emerged in December 2019 and has few effective treatments. We applied a computational drug repositioning pipeline to SARS-CoV-2 differential gene expression signatures derived from publicly available data. We utilized three independent published studies to acquire or generate lists of differentially expressed genes between control and SARS-CoV-2-infected samples. Using a rank-based pattern matching strategy based on the Kolmogorov–Smirnov Statistic, the signatures were queried against drug profiles from Connectivity Map (CMap). We validated 16 of our top predicted hits in live SARS-CoV-2 antiviral assays in either Calu-3 or 293T-ACE2 cells. Validation experiments in human cell lines showed that 11 of the 16 compounds tested to date (including clofazimine, haloperidol and others) had measurable antiviral activity against SARS-CoV-2. These initial results are encouraging as we continue to work towards a further analysis of these predicted drugs as potential therapeutics for the treatment of COVID-19.

Abstract Atom Probe Tomography (APT) is currently a well-established technique to analyse the composition of solid materials including metals, semiconductors and ceramics with up to near-atomic resolution. Using an aqueous glucose solution, we now extended the technique to frozen solutions. While the mass signals of the common glucose fragments C x H y and C x O y H z overlap with (H2O) n H from water, we achieved stoichiometrically correct values via signal deconvolution. Density functional theory (DFT) calculations were performed to investigate the stability of the detected pyranose fragments. This paper demonstrates APT’s capabilities to achieve sub-nanometre resolution in tracing whole glucose molecules in a frozen solution by using cryogenic workflows. We use a solution of defined concentration to investigate the chemical resolution capabilities as a step toward the measurement of biological molecules. Due to the evaporation of nearly intact glucose molecules, their position within the measured 3D volume of the solution can be determined with sub-nanometre resolution. Our analyses take analytical techniques to a new level, since chemical characterization methods for cryogenically-frozen solutions or biological materials are limited.

Abstract There are no clinical studies that have investigated the differences in blood serum metabolome between obstructive sleep apnea (OSA) patients and controls. In a single-center prospective observational study, we compared metabolomic profiles in the serum of OSA patients with apnea–hypopnea index (AHI) ≥ 15/h and control individuals. Peripheral blood was obtained at 3 different time points overnight: 9:00 p.m.; 5:00 a.m. and 7:00 a.m. We used a targeted approach for detecting amino acids and biogenic amines and analyzed the data with ranked general linear model for repeated measures. We recruited 31 patients with moderate-to-severe OSA and 32 controls. Significant elevations in median concentrations of alanine, proline and kynurenine in OSA patients compared to controls were detected. Significant changes in the overnight dynamics of serum concentrations occurred in OSA: glutamine, serine, threonine, tryptophan, kynurenine and glycine levels increased, whereas a fall occurred in the same biomarker levels in controls. Phenylalanine and proline levels decreased slightly, compared to a steeper fall in controls. The study indicates that serum profiles of amino acid and biogenic amines are significantly altered in patients with OSA referring to vast pathophysiologic shifts reflected in the systemic metabolism.

Directional cell locomotion requires symmetry breaking between the front and rear of the cell. In some cells, symmetry breaking manifests itself in a directional flow of actin from the front to the rear of the cell. Many cells, especially in physiological 3D matrices, do not show such coherent actin dynamics and present seemingly competing protrusion/retraction dynamics at their front and back. How symmetry breaking manifests itself for such cells is therefore elusive. We take inspiration from the scallop theorem proposed by Purcell for micro-swimmers in Newtonian fluids: self-propelled objects undergoing persistent motion at low Reynolds number must follow a cycle of shape changes that breaks temporal symmetry. We report similar observations for cells crawling in 3D. We quantified cell motion using a combination of 3D live cell imaging, visualization of the matrix displacement, and a minimal model with multipolar expansion. We show that our cells embedded in a 3D matrix form myosin-driven force dipoles at both sides of the nucleus, that locally and periodically pinch the matrix. The existence of a phase shift between the two dipoles is required for directed cell motion which manifests itself as cycles with finite area in the dipole-quadrupole diagram, a formal equivalence to the Purcell cycle. We confirm this mechanism by triggering local dipolar contractions with a laser. This leads to directed motion. Our study reveals that these cells control their motility by synchronizing dipolar forces distributed at front and back. This result opens new strategies to externally control cell motion as well as for the design of micro-crawlers.

Bacteria are ubiquitous in our daily lives, either as motile planktonic cells or as immobilized surface-attached biofilms. These different phenotypic states play key roles in agriculture, environment, industry, and medicine; hence, it is critically important to be able to predict the conditions under which bacteria transition from one state to the other. Unfortunately, these transitions depend on a dizzyingly complex array of factors that are determined by the intrinsic properties of the individual cells as well as those of their surrounding environments, and are thus challenging to describe. To address this issue, here, we develop a generally-applicable biophysical model of the interplay between motility-mediated dispersal and biofilm formation under positive quorum sensing control. Using this model, we establish a universal rule predicting how the onset and extent of biofilm formation depend collectively on cell concentration and motility, nutrient diffusion and consumption, chemotactic sensing, and autoinducer production. Our work thus provides a key step toward quantitatively predicting and controlling biofilm formation in diverse and complex settings.