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1.
Light Sci Appl ; 13(1): 243, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39251594
2.
J Agric Food Chem ; 72(36): 20048-20055, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39219102

RESUMEN

The removal of husks before the mashing process, also known as the Kubessa method, is an established brewing practice often positively associated with smoothness and better flavor-stability of beer. Empirical evidence on the effect of the Kubessa method on beer, however, has been lacking. Similarly, our study's comprehensive analysis of established brewing attributes revealed that traditional methods do not fully capture the impact of husk separation in beer brewing. Conclusive evidence of the Kubessa method's impact on beer aging chemistry was obtained through ultrahigh resolution mass spectrometry (FT-ICR-MS), revealing intricate molecular details inaccessible to conventional analytical techniques. The compositional information on thousands of molecules in Kubessa beer was resolved and compared to whole malt mashing. Machine learning algorithms applied to aging experiments identified over 500 aging-related compounds inhibited by husk separation. Complementary Time of flight mass spectrometry (ToF-MS) coupled with chromatography further confirmed that the mashing of husks introduces sulfur-containing lipid compounds. These significant differences in the beer composition provide valuable insights for further investigation into the staling protective effect of husk-separation (Kubessa process) during beer production, as empirically demonstrated in this work.


Asunto(s)
Cerveza , Manipulación de Alimentos , Espectrometría de Masas , Cerveza/análisis , Manipulación de Alimentos/métodos , Gusto , Factores de Tiempo , Grano Comestible/química
3.
Nat Commun ; 15(1): 8102, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284827

RESUMEN

Mammalian DNA replication relies on various DNA helicase and nuclease activities to ensure accurate genetic duplication, but how different helicase and nuclease activities are properly directed remains unclear. Here, we identify the ubiquitin-specific protease, USP50, as a chromatin-associated protein required to promote ongoing replication, fork restart, telomere maintenance, cellular survival following hydroxyurea or pyridostatin treatment, and suppression of DNA breaks near GC-rich sequences. We find that USP50 supports proper WRN-FEN1 localisation at or near stalled replication forks. Nascent DNA in cells lacking USP50 shows increased association of the DNA2 nuclease and RECQL4 and RECQL5 helicases and replication defects in cells lacking USP50, or FEN1 are driven by these proteins. Consequently, suppression of DNA2 or RECQL4/5 improves USP50-depleted cell resistance to agents inducing replicative stress and restores telomere stability. These data define an unexpected regulatory protein that promotes the balance of helicase and nuclease use at ongoing and stalled replication forks.


Asunto(s)
ADN Helicasas , Replicación del ADN , RecQ Helicasas , Helicasa del Síndrome de Werner , RecQ Helicasas/metabolismo , RecQ Helicasas/genética , Replicación del ADN/efectos de los fármacos , Humanos , Helicasa del Síndrome de Werner/metabolismo , Helicasa del Síndrome de Werner/genética , ADN Helicasas/metabolismo , ADN Helicasas/genética , Telómero/metabolismo , Telómero/genética , Endonucleasas de ADN Solapado/metabolismo , Endonucleasas de ADN Solapado/genética , Proteasas Ubiquitina-Específicas/metabolismo , Proteasas Ubiquitina-Específicas/genética , Células HeLa , Células HEK293 , Homeostasis del Telómero/efectos de los fármacos , Cromatina/metabolismo
4.
J Gastrointest Oncol ; 15(4): 1893-1907, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39279945

RESUMEN

Background and Objective: Magnetic resonance guided radiotherapy (MRgRT) is an emerging technological innovation with more and more institutions gaining clinical experience in this new field of radiation oncology. The ability to better visualize both tumors and healthy tissues due to excellent soft tissue contrast combined with new possibilities regarding motion management and the capability of online adaptive radiotherapy might increase tumor control rates while potentially reducing the risk of radiation-induced toxicities. As conventional computed tomography (CT)-based image guidance methods are insufficient for adaptive workflows in abdominal tumors, MRgRT appears to be an optimal method for this tumor site. The aim of this narrative review is to outline the opportunities and challenges in magnetic resonance guided radiation therapy in gastrointestinal cancers. Methods: We searched for studies, reviews and conceptual articles, including the general technique of MRgRT and the specific utilization in gastrointestinal cancers, focusing on pancreatic cancer, liver metastases and primary liver cancer, rectal cancer and esophageal cancer. Key Content and Findings: This review is highlighting the innovative approach of MRgRT in gastrointestinal cancer and gives an overview of the currently available literature with regard to clinical experiences and theoretical background. Conclusions: MRgRT is a promising new tool in radiation oncology, which can play off several of its beneficial features in the specific field of gastrointestinal cancers. However, clinical data is still scarce. Nevertheless, the available literature points out large potential for improvements regarding dose coverage and escalation as well as the reduction of dose exposure to critical organs at risk (OAR). Further prospective studies are needed to demonstrate the role of this innovative technology in gastrointestinal cancer management, in particular trials that randomly compare MRgRT with conventional CT-based image-guided radiotherapy (IGRT) would be of high value.

5.
Nat Commun ; 15(1): 7752, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39237541

RESUMEN

Time-varying metamaterials rely on large and fast changes of the linear permittivity. Beyond the linear terms, however, the effect of a non-perturbative modulation of the medium on harmonic generation remains largely unexplored. In this work, we study second harmonic generation at an optically pumped time-varying interface between air and a 310 nm Indium Tin Oxide film. We observe a modulation contrast at the second harmonic wavelength up to 93% for a pump intensity of 100 GW/cm2, leading to large frequency broadening and shift. We experimentally demonstrate that a significant contribution to the enhancement comes from the temporal modulation of the second order nonlinear susceptibility. Moreover, we show the frequency-modulated spectra resulting from single and double-slit time diffraction could be exploited for enhanced optical computing and sensing, enabling broadband time-varying effects on the harmonic signal and extending the application of Epsilon-Near-Zero materials to the visible range.

6.
Ann Surg ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39219532

RESUMEN

OBJECTIVE: To compare minimally invasive and open pancreatoduodenectomy in different subtypes of ampullary adenocarcinoma. SUMMARY BACKGROUND DATA: Ampullary adenocarcinoma (AAC) is widely seen as the best indication for minimally invasive pancreatoduodenectomy (MIPD) due to the lack of vascular involvement and dilated bile and pancreatic duct. However, it is unknown whether outcomes of MIPD for AAC differ between the pancreatobiliary (AAC-PB) and intestinal (AAC-IT) subtypes as large studies are lacking. METHODS: This is an international cohort study, encompassing 27 centers from 12 countries. Outcome of MIPD and open pancreatoduodenectomy (OPD) were compared in patients with AAC-IT and AAC-PB. Primary end points were R1 rate, lymph node yield, and 5-year overall survival (5yOS). RESULTS: Overall, 1187 patients after MIPD for AAC were included, of whom 572 with AAC-IT (62 MIPD, 510 OPD) and 615 with AAC-PB (41 MIPD and 574 OPD). The rate of R1 resection was not significantly different between MIPD and OPD for both AAC-IT (3.4% vs 6.9%, P=0,425) and AAC-PB (9.8% vs 14.9%, P=0,625). AAC-IT, more lymph nodes were resected with MIPD group (19 vs 16, P=0.007), compared to OPD. The 5y-OS did not differ after MIPD and OPD for both AAC-IT (56.8% vs 59.5%, P=0.827 and AAC-PB (52.5% vs 44.4%, P=0.357). The rates of surgical complication between MIPD and OPD did not differ between AmpIT and AmpPB. DISCUSSION: This international multicenter study found no differences in outcomes between MIPD and OPD for AAC-IT and AAC-PB. MIPD and OPD demonstrated comparable outcomes in oncological resection, survival and surgical outcomes for both subtypes of AAC.

7.
J Intern Med ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221828

RESUMEN

BACKGROUND: Vitamin-K antagonists (VKAs) have widely been replaced by non-VKA oral anticoagulants (NOACs). This includes Austria, Germany and Switzerland, where as VKA, instead of warfarin, the much longer-acting phenprocoumon is used, which was not compared to NOACs in clinical trials. METHODS: Using administrative data from a large German health insurance, we included all anticoagulation-naïve patients with a first prescription of a NOAC or VKA between 2012 and 2020. We analysed overall survival, major adverse cardiac and cerebrovascular events, major thromboembolic events and major bleeding. RESULTS: Overall, 570,137 patients were included (apixaban: 26.9%, dabigatran: 4.6%, edoxaban: 8.8%, rivaroxaban: 39.1% and VKA: 20.7% of these 99.4% phenprocoumon). In the primary analysis using a 1:1 propensity score matching-cohort (PSM-cohort), a significantly higher overall mortality was found for apixaban, edoxaban and rivaroxaban (all p < 0.001) but not for dabigatran (p = 0.13) compared to VKA. In this PSM-cohort, 5-year mortality was 22.7% for apixaban versus 12.7% for VKA, 19.5% for edoxaban versus 11.4% for VKA, 16.0% for rivaroxaban versus 12.3% for VKA (all p < 0.001) and 13.0% for dabigatran versus 12.8% for VKA (p = 0.06). The observed effect was confirmed in sensitivity analyses using un-weighted and three different weighted Fine-Gray regression models on the basis of the entire cohort. CONCLUSIONS: In this large real-world analysis, apixaban, edoxaban and rivaroxaban, but not dabigatran, were associated with worse survival compared to VKA. These findings, consistent with a few other studies including phenprocoumon, cast profound doubts on the unreflected, general use of NOACs. Randomized trials should assess whether phenprocoumon might actually be superior to NOACs.

8.
Neurobiol Stress ; 31: 100658, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39100725

RESUMEN

Introduction: At the maternal-fetal interface in pregnancy, stress during pregnancy can lead to an increased vulnerability to later psychopathology of the fetus. Potential mediators of this association have scarcely been studied and may include early alterations of fetal brain-derived neurotrophic factor (BDNF). Amniotic fluid is of particular interest for effects on fetal endocrine alterations, as the assessment in amniotic fluid allows for measurements over a time integral. This study hypothesized that maternal psychometrics, socioeconomic status and glucocorticoids are related to BDNF levels in amniotic fluid at birth. The association of fetal BDNF with newborn anthropometrics was tested. Methods: Women near term who underwent elective cesarean section and their newborns were investigated (n = 37). Maternal psychometrics, socioeconomic status and glucocorticoids (the sum of cortisol and cortisone) in amniotic fluid at birth were analyzed for an association with fetal BDNF in amniotic fluid at birth. Newborn anthropometrics were assessed by length, weight, head circumference and gestational age at birth. Results: In bivariate analysis, maternal psychometrics and socioeconomic status were not related to fetal BDNF in amniotic fluid at birth. The sum of cortisol and cortisone related to increased fetal BDNF in amniotic fluid at birth (r = 0.745, p < 0.001). BDNF in amniotic fluid was associated negatively with fetal birth weight per gestational age (r = -0.519, p < 0.001), length per gestational age (r = -0.374, p = 0.023), head circumference per gestational age (r = -0.508, p = 0.001), but not with gestational age at birth. In multiple regression analysis, the sum of cortisol and cortisone (p < 0.001) and birth weight per gestational age (p = 0.012) related to higher fetal BDNF levels in amniotic fluid at birth (R2 = 0.740, p < 0.001) when controlling for fetal sex and maternal age. Head circumference per gestational age predicted fetal BDNF with borderline significance (p = 0.058) when controlling for confounders. Conclusion: Glucocorticoids in amniotic fluid were positively associated with high fetal BDNF at birth, which may be an adaptive fetal response. Maternal psychological variables and socioeconomic status did not link to fetal BDNF. Birth weight and head circumference per gestational age were inversely associated with fetal BDNF at birth, which may represent a compensatory upregulation of BDNF in fetuses with low anthropometrics. Longitudinal studies are needed to assess the role of stress during pregnancy on later offspring development. The analysis of additional fetal growth factors and inflammation upon maternal stress in further biomaterials such as the placenta is warranted, to understand mechanistic alterations of how maternal stress links to fetal development and an increased vulnerability for psychopathology.

9.
Sci Adv ; 10(32): eadp1890, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39110806

RESUMEN

Surface charges play a fundamental role in physics and chemistry, in particular in shaping the catalytic properties of nanomaterials. However, tracking nanoscale surface charge dynamics remains challenging due to the involved length and time scales. Here, we demonstrate time-resolved access to the nanoscale charge dynamics on dielectric nanoparticles using reaction nanoscopy. We present a four-dimensional visualization of the spatiotemporal evolution of the charge density on individual SiO2 nanoparticles under strong-field irradiation with femtosecond-nanometer resolution. The initially localized surface charges exhibit a biexponential redistribution over time. Our findings reveal the influence of surface charges on surface molecular bonding through quantum dynamical simulations. We performed semi-classical simulations to uncover the roles of diffusion and charge loss in the surface charge redistribution process. Understanding nanoscale surface charge dynamics and its influence on chemical bonding on a single-nanoparticle level unlocks an increased ability to address global needs in renewable energy and advanced health care.

10.
Eur J Clin Nutr ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39117905

RESUMEN

BACKGROUND & AIMS: Muscle quality index (MQI) can be computed in various ways. Also, many studies have evaluated MQI in older adults and non-Hispanic populations. The aim of this study was to compare various muscle quality indexes between Hispanics and non-Hispanic Caucasians when stratifying grip strength and appendicular lean mass measurements. METHODS: 235 participants (aged 25.5 ± 9.5 for males and 26.4 ± 9.9 for females) completed a dual energy X-ray absorptiometry (DXA) scan to assess appendicular lean mass (ALM). Handgrip strength (HGS) was assessed using a handheld dynamometer. MQI was computed using four different models: 1). MQIRA: ALM and HGS of right arm and hand, respectively; 2). MQILA: ALM and HGS of left arm and hand, respectively; 3). MQIARMS: ALM and HGS of both arms and hands, respectively; and 4). MQITOTAL: ALM of upper and lower-limbs and HGS of left and right hand. RESULTS: Hispanic males and females exhibited lower HGS compared to Caucasians with effect sizes ranging from trivial (d = 0.17) to moderate (d = 0.80). Females demonstrated higher MQI values compared to males for MQIARMS (d = 0.70), MQIRA (d = 0.75), and MQILA (d = 0.57). However, MQITOTAL yielded a small practical effect (d = 0.33) in favor of males (3.2 ± 0.5 kg/kg vs. 3.1 ± 0.5 kg/kg). After factoring by sex and ethnicity, Hispanic males and females, compared to non-Hispanic Caucasians males and females, showed trivial-to-small practical differences (d values ranging from 0.03 to 0.39). CONCLUSIONS: These results demonstrate MQI models vary across sex, particularly when utilizing models that account for upper extremity strength and ALM (i.e., MQIARMS, MQIRA, and MQILA). Lastly, to establish consistency in future research, the present study recommends using MQI models that account for ALM of upper- and lower-limbs (i.e., MQITOTAL). However, research measuring muscular strength via one upper-limb (e.g., left hand) might consider measuring ALM of the corresponding arm (e.g., left arm) when computing muscle quality (e.g., MQILA).

11.
Strahlenther Onkol ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39120747

RESUMEN

BACKGROUND: The use of positron-emission tomography (PET)/computed tomography (CT) in radiation therapy (RT) has increased. Radiation oncologists (RadOncs) have access to PET/CT with a variety of tracers for different tumor entities and use it for target volume definition. The German Society of Nuclear Medicine (DGN) and the German Society of Radiation Oncology (DEGRO) aimed to identify current patterns of care in order to improve interdisciplinary collaboration. METHODS: We created an online survey on participating RadOncs' use of PET tracers for different tumor entities and how they affect RT indication, dose prescription, and target volume definition. Further topics were reimbursement of PET/CT and organizational information (fixed timeslots and use of PET with an immobilization device [planning/RT-PET]). The survey contained 31 questions in German language (yes/no questions, multiple choice [MC] questions, multiple select [MS] questions, and free-text entry options). The survey was distributed twice via the DEGRO member mailing list. RESULTS: During the survey period (May 22-August 7, 2023) a total of 156 RadOncs (13% of respondents) answered the survey. Among these, 59% reported access to diagnostic PET/CT within their organization/clinic and 24% have fixed timeslots for their patients. 37% of survey participants can perform RT-PET and 29% have the option of providing a dedicated RT technician for planning PET. Besides [18F]-fluorodeoxyglucose (FDG; mainly used in lung cancer: 95%), diagnostic prostate-specific membrane antigen (PSMA)-PET/CT for RT of prostate cancer is routinely used by 44% of participants (by 64% in salvage RT). Use of amino acid PET in brain tumors and somatostatin receptor PET in meningioma is low (19 and 25%, respectively). Scans are reimbursed through private (75%) or compulsory (55%) health insurance or as part of indications approved by the German Joint Federal Committee (Gemeinsamer Bundesausschuss; 59%). 98% of RadOncs agree that PET impacts target volume definition and 62% think that it impacts RT dose prescription. DISCUSSION: This is the first nationwide survey on the role of PET/CT for RT planning among RadOncs in Germany. We find high acceptance of PET results for treatment decisions and target volume definition. Planning PET comes with logistic challenges for different healthcare settings (e.g., private practices vs. university hospitals). The decision to request PET/CT is often based on the possibility of reimbursement. CONCLUSION: PET/CT has become an important tool for RadOncs, with several indications. However, access is still limited at several sites, especially for dedicated RT-PET. This study aims to improve interdisciplinary cooperation and adequate implementation of current guidelines for the treatment of various tumor entities.

12.
Cureus ; 16(7): e64786, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39156313

RESUMEN

Around the world, lung cancer is the leading cause of cancer-related death and the most commonly diagnosed cancer. In the early stages, surgery is the preferable therapeutic strategy. We present the case of a male patient aged 49 years diagnosed with non-small cell lung cancer of the left lower lobe who was referred for a radical left pneumonectomy. After careful preoperative preparation, the surgery was proceeded with. During the surgery, the patient needed bronchoscopy for the aspiration of the trachea and bronchial tree; after the aspiration procedure, an intraoperative massive hemorrhage started, with shock and ventricular tachycardia. Nine days after surgery, the patient developed a pulmonary embolism and returned to the ICU. The patient benefited from transfusion, intrathoracic cardiac compressions, pulse index continuous cardiac output (PiCCO), renal replacement therapy (RRT), anticoagulation, and intensive care. After a complicated clinical course, the patient is discharged, and after more than 18 months, the patient comes regularly for follow-up consultation in good health.

13.
Chem Sci ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39170723

RESUMEN

Legislative change and shifting consumer sentiment drive a need to replace polymers in certain products. Herein, we highlight that eutectic molecular glasses and liquids are promising but underutilized candidate materials. We formulate a series of hydrophobic eutectic molecular liquids and glasses by mixing their crystalline components. The eutectic composition of each mixture was determined by both differential scanning calorimetry (DSC) and UV-vis spectroscopic measurements, which were processed and analyzed using a trained partial least squares regression model. With product shelf-life in mind, the long-term stability (up to 14 months) of the amorphous materials towards crystallization was proven using powder X-ray diffraction (PXRD). Molecular dynamics (MD) simulations put forward potential design rules in terms of the physical stability of these glasses. Rheological properties were investigated from the perspective of processability. Low fragility indices were found for all liquids, aiding processability through glassblowing, fiber pulling, film formation and molding. We show that properties can be tailored by blending two different eutectic systems or simply adding a plasticizer. To demonstrate a potential application area, the 4-hydroxychalcone and bifonazole eutectic system was used as a matrix for controlled release studies of a model active ingredient.

14.
J Med Chem ; 67(16): 14553-14573, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39116445

RESUMEN

ACKR3, an atypical chemokine receptor, has been associated with prothrombotic events and the development of cardiovascular events. We designed, synthesized, and evaluated a series of novel small molecule ACKR3 agonists. Extensive structure-activity relationship studies resulted in several promising agonists with potencies ranging from the low micromolar to nanomolar range, for example, 23 (EC50 = 111 nM, Emax = 95%) and 27 (EC50 = 69 nM, Emax = 82%) in the ß-arrestin-recruitment assay. These compounds are selective for ACKR3 versus ACKR2, CXCR3, and CXCR4. Several agonists were subjected to investigations of their P-selectin expression reduction in the flow cytometry experiments. In particular, compounds 23 and 27 showed the highest potency for platelet aggregation inhibition, up to 80% and 97%, respectively. The most promising compounds, especially 27, exhibited good solubility, metabolic stability, and no cytotoxicity, suggesting a potential tool compound for the treatment of platelet-mediated thrombosis.


Asunto(s)
Diseño de Fármacos , Inhibidores de Agregación Plaquetaria , Agregación Plaquetaria , Receptores CXCR , Humanos , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/síntesis química , Inhibidores de Agregación Plaquetaria/química , Relación Estructura-Actividad , Agregación Plaquetaria/efectos de los fármacos , Receptores CXCR/agonistas , Receptores CXCR/metabolismo , Animales , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/síntesis química , Selectina-P/metabolismo , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo
15.
Adv Mater ; : e2405978, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092689

RESUMEN

Photonic metasurfaces offer exceptional control over light at the nanoscale, facilitating applications spanning from biosensing, and nonlinear optics to photocatalysis. Many metasurfaces, especially resonant ones, rely on periodicity for the collective mode to form, which makes them subject to the influences of finite size effects, defects, and edge effects, which have considerable negative impact at the application level. These aspects are especially important for quasi-bound state in the continuum (BIC) metasurfaces, for which the collective mode is highly sensitive to perturbations due to high-quality factors and strong near-field enhancement. Here, the mode formation in quasi-BIC metasurfaces on the individual resonator level using scattering scanning near-field optical microscopy (s-SNOM) in combination with a new image processing technique, is quantitatively investigated. It is found that the quasi-BIC mode is formed at a minimum size of 10 × 10-unit cells much smaller than expected from far-field measurements. Furthermore, it is shown that the coupling direction of the resonators, defects and edge states have pronounced influence on the quasi-BIC mode. This study serves as a link between the far-field and near-field responses of metasurfaces, offering crucial insights for optimizing spatial footprint and active area, holding promise for augmenting applications such as catalysis and biospectroscopy.

16.
Nat Neurosci ; 27(9): 1668-1674, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39103558

RESUMEN

Amyloid-ß (Aß) is thought to be neuronally derived in Alzheimer's disease (AD). However, transcripts of amyloid precursor protein (APP) and amyloidogenic enzymes are equally abundant in oligodendrocytes (OLs). By cell-type-specific deletion of Bace1 in a humanized knock-in AD model, APPNLGF, we demonstrate that OLs and neurons contribute to Aß plaque burden. For rapid plaque seeding, excitatory projection neurons must provide a threshold level of Aß. Ultimately, our findings are relevant for AD prevention and therapeutic strategies.


Asunto(s)
Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide , Péptidos beta-Amiloides , Ácido Aspártico Endopeptidasas , Neuronas , Oligodendroglía , Placa Amiloide , Animales , Humanos , Ratones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Modelos Animales de Enfermedad , Ratones Transgénicos , Neuronas/metabolismo , Neuronas/patología , Oligodendroglía/metabolismo , Oligodendroglía/patología , Placa Amiloide/patología , Placa Amiloide/metabolismo
17.
Neuroimage ; 298: 120793, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39153520

RESUMEN

Diffuse correlation spectroscopy (DCS) is a powerful tool for assessing microvascular hemodynamic in deep tissues. Recent advances in sensors, lasers, and deep learning have further boosted the development of new DCS methods. However, newcomers might feel overwhelmed, not only by the already-complex DCS theoretical framework but also by the broad range of component options and system architectures. To facilitate new entry to this exciting field, we present a comprehensive review of DCS hardware architectures (continuous-wave, frequency-domain, and time-domain) and summarize corresponding theoretical models. Further, we discuss new applications of highly integrated silicon single-photon avalanche diode (SPAD) sensors in DCS, compare SPADs with existing sensors, and review other components (lasers, sensors, and correlators), as well as data analysis tools, including deep learning. Potential applications in medical diagnosis are discussed and an outlook for the future directions is provided, to offer effective guidance to embark on DCS research.


Asunto(s)
Análisis Espectral , Humanos , Análisis Espectral/métodos , Análisis Espectral/instrumentación , Aprendizaje Profundo , Hemodinámica/fisiología
18.
Nat Nanotechnol ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187580

RESUMEN

To control and enhance light-matter interactions at the nanoscale, two parameters are central: the spectral overlap between an optical cavity mode and the material's spectral features (for example, excitonic or molecular absorption lines), and the quality factor of the cavity. Controlling both parameters simultaneously would enable the investigation of systems with complex spectral features, such as multicomponent molecular mixtures or heterogeneous solid-state materials. So far, it has been possible only to sample a limited set of data points within this two-dimensional parameter space. Here we introduce a nanophotonic approach that can simultaneously and continuously encode the spectral and quality-factor parameter space within a compact spatial area. We use a dual-gradient metasurface design composed of a two-dimensional array of smoothly varying subwavelength nanoresonators, each supporting a unique mode based on symmetry-protected bound states in the continuum. This results in 27,500 distinct modes and a mode density approaching the theoretical upper limit for metasurfaces. By applying our platform to surface-enhanced molecular spectroscopy, we find that the optimal quality factor for maximum sensitivity depends on the amount of analyte, enabling effective molecular detection regardless of analyte concentration within a single dual-gradient metasurface. Our design provides a method to analyse the complete spectral and coupling-strength parameter space of complex material systems for applications such as photocatalysis, chemical sensing and entangled photon generation.

19.
Artículo en Inglés | MEDLINE | ID: mdl-39163321

RESUMEN

INTRODUCTION: Refractory pain is a major clinical problem in patients with pancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis (CP). New, effective therapies to reduce pain are urgently needed. Intravenous lidocaine is used in clinical practice in patients with PDAC and CP, but its efficacy has not been studied prospectively. METHODS: Multicentre prospective non-randomized pilot study including patients with moderate or severe pain (NRS ≥ 4) associated with PDAC or CP in 5 Dutch centers. An intravenous lidocaine bolus of 1.5mg/kg, was followed by continuous infusion at 1.5 mg/kg/hour. The dose was raised every 15 minutes until treatment response (up to a maximum 2mg/kg/hour) and consecutively administered for two hours. Primary outcome was the mean difference in pain severity, pre-infusion and the first day after (Brief Pain Inventory [BPI] scale 1-10). A BPI decrease ≥ 1.3 points was considered clinically relevant. RESULTS: Overall, 30 patients were included, 19 with PDAC (63%) and 11 with CP (37%). The mean difference in BPI at day one was 1.1 (SD±1.3) points for patients with PDAC and 0.5 (SD±1.7) for CP patients. A clinically relevant decrease in BPI on day one was reported in 9/29 patients (31%), this response lasted up to one month. No serious complications were reported, and only three minor complications (vertigo, nausea, tingling of mouth). Treatment with lidocaine did not impact quality of life. CONCLUSION: Intravenous lidocaine in patients with painful PDAC and CP did not show an overall clinically relevant reduction of pain. However, this pilot study shows that the treatment is feasible in this patient group, and had a positive effect in a third of patients which lasted up to a month with only minor side effects. To prove or exclude the efficacy of intravenous lidocaine, the study should be performed in a study with a greater sample size and less heterogeneous patient group.

20.
Nat Commun ; 15(1): 7050, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147735

RESUMEN

Achieving precise spectral and temporal light manipulation at the nanoscale remains a critical challenge in nanophotonics. While photonic bound states in the continuum (BICs) have emerged as a powerful means of controlling light, their reliance on geometrical symmetry breaking for obtaining tailored resonances makes them highly susceptible to fabrication imperfections, and their generally fixed asymmetry factor fundamentally limits applications in reconfigurable metasurfaces. Here, we introduce the concept of environmental symmetry breaking by embedding identical resonators into a surrounding medium with carefully placed regions of contrasting refractive indexes, activating permittivity-driven quasi-BIC resonances (ε-qBICs) without altering the underlying resonator geometry and unlocking an additional degree of freedom for light manipulation through active tuning of the surrounding dielectric environment. We demonstrate this concept by integrating polyaniline (PANI), an electro-optically active polymer, to achieve electrically reconfigurable ε-qBICs. This integration not only demonstrates rapid switching speeds and exceptional durability but also boosts the system's optical response to environmental perturbations. Our strategy significantly expands the capabilities of resonant light manipulation through permittivity modulation, opening avenues for on-chip optical devices, advanced sensing, and beyond.

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