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BACKGROUND: Diminished systemic serum butyrylcholinesterase (BChE), a biomarker for chronic inflammation, cachexia, and advanced tumor stage, has shown to play a prognostic role in various malignancies. The aim of this study was to investigate the prognostic value of pretherapeutic BChE levels in patients with resectable adenocarcinoma of the gastroesophageal junction (AEG), treated with or without neoadjuvant therapy. METHODS: Data of a consecutive series of patients with resectable AEG at the Department for General Surgery, Medical University of Vienna, were analyzed. Preoperative serum BChE levels were correlated to clinic-pathological parameters as well as treatment response. The prognostic impact of serum BChE levels on disease-free (DFS) and overall survival (OS) was evaluated by univariate and multivariate cox regression analysis, and Kaplan-Meier curves used for illustration. RESULTS: A total of 319 patients were included in this study, with an overall mean (standard deviation, SD) pretreatment serum BChE level of 6.22 (± 1.91) IU/L. In univariate models, diminished preoperative serum BChE levels were significantly associated with shorter overall (OS, p < 0.003) and disease-free survival (DFS, p < 0.001) in patients who received neoadjuvant treatment and/or primary resection. In multivariated analysis, decreased BChE was significantly associated with shorter DFS (HR: 0.92, 95% CI: 0.84-1.00, p 0.049) and OS (HR: 0.92, 95% CI: 0.85-1.00, p < 0.49) in patients receiving neoadjuvant therapy. Backward regression identified the interaction between preoperative BChE and neoadjuvant chemotherapy as a predictive factor for DFS and OS. CONCLUSION: Diminished serum BChE serves as a strong, independent, and cost-effective prognostic biomarker for worse outcome in patients with resectable AEG who had received neoadjuvant chemotherapy.
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Butirilcolinesterase , Terapia Neoadjuvante , Humanos , Prognóstico , Biomarcadores , Análise Multivariada , Estudos RetrospectivosRESUMO
BACKGROUND AND OBJECTIVES: ChatGPT is a natural language processing chatbot with increasing applicability to the medical workflow. Although ChatGPT has been shown to be capable of passing the American Board of Neurological Surgery board examination, there has never been an evaluation of the chatbot in triaging and diagnosing novel neurosurgical scenarios without defined answer choices. In this study, we assess ChatGPT's capability to determine the emergent nature of neurosurgical scenarios and make diagnoses based on information one would find in a neurosurgical consult. METHODS: Thirty clinical scenarios were given to 3 attendings, 4 residents, 2 physician assistants, and 2 subinterns. Participants were asked to determine if the scenario constituted an urgent neurosurgical consultation and what the most likely diagnosis was. Attending responses provided a consensus to use as the answer key. Generative pretraining transformer (GPT) 3.5 and GPT 4 were given the same questions, and their responses were compared with the other participants. RESULTS: GPT 4 was 100% accurate in both diagnosis and triage of the scenarios. GPT 3.5 had an accuracy of 92.59%, slightly below that of a PGY1 (96.3%), an 88.24% sensitivity, 100% specificity, 100% positive predictive value, and 83.3% negative predicative value in triaging each situation. When making a diagnosis, GPT 3.5 had an accuracy of 92.59%, which was higher than the subinterns and similar to resident responders. CONCLUSION: GPT 4 is able to diagnose and triage neurosurgical scenarios at the level of a senior neurosurgical resident. There has been a clear improvement between GPT 3.5 and 4. It is likely that the recent updates in internet access and directing the functionality of ChatGPT will further improve its utility in neurosurgical triage.
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Neurocirurgia , Triagem , Humanos , Triagem/métodos , Neurocirurgia/educação , Processamento de Linguagem Natural , Procedimentos Neurocirúrgicos/métodos , Internato e ResidênciaRESUMO
Neuroendocrine analyses of posttraumatic stress disorder (PTSD) have generally focused on hypothalamic-pituitary-adrenal (HPA) axis alterations. In the present analyses, we examine two additional neuroendocrine factors that have been previously implicated in biological stress responses: oxytocin (OT) and arginine vasopressin (AVP). Here we examined basal neuropeptide status in military veterans clinically diagnosed with PTSD (n = 29) and in two non-traumatized comparison groups with previous stress exposure (n = 11 SWAT trainees and n = 21 ultramarathon runners). PTSD patients showed low levels of plasma OT and high levels of AVP. The ratio of AVP/OT robustly related to PTSD status, and emerged as a statistically plausible mediator of relationships between the number of personal traumatic experiences and subsequent PTSD symptom burden. Over the course of behavioral therapy for PTSD, measures of OT showed a significant but modest normalization. Plasma cortisol levels were not statistically different among the three groups. This study suggests that AVP/OT ratios may represent a neuroendocrine predictor of severe PTSD, as well as a potential treatment response biomarker.
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Matteson homologations of chiral boronic esters proved to be an excellent tool for the synthesis of highly functionalized amino and hydroxy acid residues. This method provides straightforward stereoselective access to the side chain of callipeltin A, a natural marine product with interesting biological activities. Furthermore, this protocol should allow for variations in the substitution pattern in future SAR studies, simply by choosing suitable nucleophiles during the homologation steps.
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Depsipeptídeos , Ésteres , Hidroxiácidos , EstereoisomerismoRESUMO
Both paralogs of the calcium-dependent activator protein for secretion (CAPS) are required for exocytosis of synaptic vesicles (SVs) and large dense core vesicles (LDCVs). Despite approximately 80% sequence identity, CAPS1 and CAPS2 have distinct functions in promoting exocytosis of SVs and LDCVs in dorsal root ganglion (DRG) neurons. However, the molecular mechanisms underlying these differences remain enigmatic. In this study, we applied high- and super-resolution imaging techniques to systematically assess the subcellular localization of CAPS paralogs in DRG neurons deficient in both CAPS1 and CAPS2. CAPS1 was found to be more enriched at the synapses. Using - in-depth sequence analysis, we identified a unique CAPS1 N-terminal sequence, which we introduced into CAPS2. This CAPS1/2 chimera reproduced the pre-synaptic localization of CAPS1 and partially rescued synaptic transmission in neurons devoid of CAPS1 and CAPS2. Using immunoprecipitation combined with mass spectrometry, we identified CAPS1-specific interaction partners that could be responsible for its pre-synaptic enrichment. Taken together, these data suggest an important role of the CAPS1-N terminus in the localization of the protein at pre-synapses.
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Prior carburization of semi-finished steel sheets is a new process variant in hot stamping to manufacture parts with tailored properties. Compared to conventional hot stamping processes, a complex phase typed steel alloy is used instead of 22MnB5. Yet recent investigations focused on final mechanical properties rather than microstructural mechanisms cause an increase in strength. Thus, the influence of additional carburization on the microstructural evolution during hot stamping of a complex phase steel CP-W®800 is investigated within this work. The phase transformation behavior, as well as the grain growth during austenitization, is evaluated by in-situ measurements employing a laser-ultrasound sensor. The results are correlated with additional hardness measurements in as-quenched condition and supplementary micrographs. The experiments reveal that the carburization process significantly improves the hardenability of the CP-W®800. However, even at quenching rates of 70 K/s no fully martensitic microstructure was achievable. Still, the resulting hardness of the carburized samples might exceed the fully martensitic hardness of 22MnB5 derived from literature. Furthermore, the carburization process has no adverse effect on the fine grain stability of the complex phase steel. This makes it more robust in terms of grain size than the conventional hot stamping steel 22MnB5.
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Mammals, including humans, are reliant for survival and reproduction on adaptations associated with sociality and physiological investment, which can be linked to interactions with their parents or other bonded adult conspecifics. A wide range of evidence in human and non-human mammal species links social behaviors and relationships - including those characterized by what humans call "love" - to positive health and longevity. In light of this evidence, we propose a Social Dependency Hypothesis of Longevity, suggesting that natural selection has favored longer and healthier adult lives in species or in individuals exhibiting enhanced caregiver responsibilities contributing to the success of the next generation. In highlighting cellular, physiological, and behavioral effects of mammalian reproductive hormones, we examine the specific hypothesis that the neuropeptide oxytocin links longevity to the benefits of parental investment and associated relationships. Oxytocin is a pleiotropic molecule with anti-oxidant and anti-inflammatory properties, capable of regulating the hypothalamic-pituitary-adrenal axis, the parasympathetic nervous system and other systems associated with the management of various challenges, including chronic diseases and therefore may be crucial to establishing the maximum longevity potential of a species or an individual.
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The interaction of ultrashort pulsed laser radiation with intensities of 1013 W cm-2 and above with materials often results in an unexpected high X-ray photon flux. It has been shown so far, on the one hand, that X-ray photon emissions increase proportionally with higher laser power and the accumulated X-ray dose rates can cause serious health risks for the laser operators. On the other hand, there is clear evidence that little variations of the operational conditions can considerably affect the spectral X-ray photon flux and X-ray emissions dose. In order to enhance the knowledge in this field, four ultrashort pulse laser systems for providing different complementary beam characteristics were employed in this study on laser-induced X-ray emissions, including peak intensities between 8 × 1012 Wâcm-2 < I0 < 5.2 × 1016 Wâcm-2, up to 72.2 W average laser power as well as burst/bi-burst processing mode. By the example of AISI 304 stainless steel, it was verified that X-ray emission dose rates as high as HË' (0.07) > 45 mSv h-1 can be produced when low-intensity ultrashort pulses irradiate at a small 1 µm intra-line pulse distance during laser beam scanning and megahertz pulse repetition frequencies. For burst and bi-burst pulses, the second intra-burst pulse was found to significantly enhance the X-ray emission potentially induced by laser pulse and plasma interaction.
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Despite evidence supporting a role for oxytocin (OT) in regulating social behavior, surprisingly little is known about how this neuropeptide is calibrated during development. We systematically reviewed empirical studies in humans (k = 86 publications reporting on 66 independent samples; N = 7319) that examined associations between early-life stress and three OT system components: endogenous OT, methylation of the OT receptor gene (OXTRm), and biological and behavioral responses to intranasally administered OT. In a series of meta-analyses, we found some evidence that people who grew up under more adverse conditions tend to have lower endogenous OT (children: r = .12; adults: r = .09), that early adversity is associated with higher levels of OXTRm (r = .02), and that adults who report lower levels of childhood adversity tend to show more positive responses to intranasally administered OT (r = .12). These results were found in typical populations, and were in most cases absent in clinical samples. We discuss these findings in terms of both the prevailing medical model (focusing on the harmful effects of early-life stress) and the adaptive calibration model (focusing on developmental adaptation of biobehavioral systems to early conditions) and suggest that an adaptation-based approach could meaningfully advance research and intervention on the sequelae of early adversity.
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Experiências Adversas da Infância , Ocitocina , Adulto , Criança , Humanos , Receptores de Ocitocina/genética , Comportamento SocialRESUMO
Excitons dominate the light absorption and re-emission spectra of monolayer transition-metal dichalcogenides (TMD). Microscopic investigations of the excitonic response in TMD almost invariably extract information from the radiative recombination step, which only constitutes one part of the picture. Here, by exploiting imaging spectroscopic ellipsometry (ISE), we investigate the spatial dependence of the dielectric function of chemical vapor deposition (CVD)-grown WS2 flakes with a microscopic lateral resolution, thus providing information about the spatially varying, exciton-induced light absorption in the monolayer WS2. Comparing the ISE results with imaging photoluminescence spectroscopy data, the presence of several correlated features was observed, along with the unexpected existence of a few uncorrelated characteristics. The latter demonstrates that the exciton-induced absorption and emission features are not always proportional at the microscopic scale. Microstructural modulations across the flakes, having a different influence on the absorption and re-emission of light, are deemed responsible for the effect.
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Local crystallization of ferromagnetic layers is crucial in the successful realization of miniaturized tunneling magnetoresistance (TMR) devices. In the case of Co-Fe-B TMR devices, used most successfully so far in applications and devices, Co-Fe-B layers are initially deposited in an amorphous state and annealed post-deposition to induce crystallization in Co-Fe, thereby increasing the device performance. In this work, first direct proof of locally triggered crystallization of 10 nm thick Co-Fe-B films by laser irradiation is provided by means of X-ray diffraction (XRD) using synchrotron radiation. A comparison with furnace annealing is performed for benchmarking purposes, covering different annealing parameters, including temperature and duration in the case of furnace annealing, as well as laser intensity and scanning speed for the laser annealing. Films of Co-Fe-B with different stoichiometry sandwiched between a Ru and a Ta or MgO layer were systematically assessed by XRD and SQUID magnetometry in order to elucidate the crystallization mechanisms. The transformation of Co-Fe-B films from amorphous to crystalline is revealed by the presence of pronounced CoFe(110) and/or CoFe(200) reflexes in the XRD θ-2θ scans, depending on the capping layer. For a certain window of parameters, comparable crystallization yields are obtained with furnace and laser annealing. Samples with an MgO capping layer required a slightly lower laser intensity to achieve equivalent Co-Fe crystallization yields, highlighting the potential of laser annealing to locally enhance the TMR ratio.
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N-(α-Hydroxyacyl)-glycinesters can be used as excellent nucleophiles in Pd-catalyzed allylic alkylation. The method allows for the stereoselective introduction of a wide range of side chains, including highly functionalized ones. Both diastereomers can be accessed through variation of the reaction conditions. Furthermore, the use of stannylated carbonates introduces vinylstannane motifs, which are eligible for subsequent C-C coupling reactions.
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BACKGROUND: Due to the rising interest in Europe to treat large cartilage defects with osteochondrale allografts, research aims to find a suitable solution for long-term storage of osteochondral allografts. This is further encouraged by the fact that legal restrictions currently limit the use of the ingredients from animal or human sources that are being used in other regions of the world (e.g. in the USA). Therefore, the aim of this study was A) to analyze if a Lactated Ringer (LR) based solution is as efficient as a Dulbecco modified Eagle's minimal essential medium (DMEM) in maintaining chondrocyte viability and B) at which storage temperature (4°C vs. 37°C) chondrocyte survival of the osteochondral allograft is optimally sustained. METHODS: 300 cartilage grafts were collected from knees of ten one year-old Black Head German Sheep. The grafts were stored in four different storage solutions (one of them DMEM-based, the other three based on Lactated Ringer Solution), at two different temperatures (4 and 37°C) for 14 and 56days. At both points in time, chondrocyte survival as well as death rate, Glycosaminoglycan (GAG) content, and Hydroxyproline (HP) concentration were measured and compared between the grafts stored in the different solutions and at the different temperatures. RESULTS: Independent of the storage solutions tested, chondrocyte survival rates were higher when stored at 4°C compared to storage at 37°C both after short-term (14days) and long-term storage (56days). At no point in time did the DMEM-based solution show a superior chondrocyte survival compared to lactated Ringer based solution. GAG and HP content were comparable across all time points, temperatures and solutions. CONCLUSION: LR based solutions that contain only substances that are approved in Germany may be just as efficient for storing grafts as the USA DMEM-based solution gold standard. Moreover, in the present experiment storage of osteochondral allografts at 4°C was superior to storage at 37°C.
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Aloenxertos/citologia , Cartilagem Articular/citologia , Condrócitos/citologia , Manejo de Espécimes/métodos , Preservação de Tecido/métodos , Transplante Homólogo , Animais , Técnicas de Cultura de Células , Sobrevivência Celular , Condrócitos/transplante , Temperatura Baixa , Soluções Isotônicas/farmacologia , Soluções para Preservação de Órgãos/farmacologia , Lactato de Ringer , OvinosRESUMO
PURPOSE: As previous data had shown that only two-thirds of patients had the predicted activity time courses when PEG-asparaginase 1000 U/m(2) was used in reinduction after native E. coli asparaginase in induction treatment of acute lymphoblastic leukaemia (ALL), drug monitoring was performed with the use of a higher dose. METHODS: Because one-third of patients had insufficient serum asparaginase activity time courses after a single dose of 1000 U/m(2) PEG-asparaginase during reinduction treatment, a dose of 2500 U/m(2) PEG-asparaginase, which is the approved dosage in Germany, was used in 39 reinduction and 20 relapse patients to determine whether prolongation of the activity time course may be possible with this higher dose, and to look for significant differences between reinduction and relapse patients. RESULTS: After 1, 2 and 3 weeks, the mean activities were 1113 +/- 699 U/l, 231 +/- 259 U/l, and 13 +/- 35 U/l in the reinduction patients, and 1078 +/- 649 U/l, 165 +/- 195 U/l and 19 +/- 28 U/l in the relapse patients, respectively. There were a considerable number of patients with a substantially shortened activity time course in both groups. In 10 of 39 reinduction patients and in 7 of 24 doses during relapse treatment, only activities <100 U/l were found after 1 week with a further fast decline. No statistically significant differences between the two patient groups could be shown at any time-point. CONCLUSIONS: Comparison of these data with activities after 1000 U/m(2) PEG-asparaginase showed no prolongation of the time with activity in the therapeutic range with the higher dose. Therefore, for a longer duration of therapeutic activity, administration of further doses is mandatory.