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1.
Elife ; 122024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39401075

RESUMEN

Channelrhodopsins (ChRs) are light-gated ion channels widely used to optically activate or silence selected electrogenic cells, such as individual brain neurons. Here, we describe identifying and characterizing a set of anion-conducting ChRs (ACRs) from diverse taxa and representing various branches of the ChR phylogenetic tree. The Mantoniella squamata ACR (MsACR1) showed high sensitivity to yellow-green light (λmax at 555 nm) and was further engineered for optogenetic applications. A single amino-acid substitution that mimicked red-light-sensitive rhodopsins like Chrimson shifted the photosensitivity 20 nm toward red light and accelerated photocurrent kinetics. Hence, it was named red and accelerated ACR, raACR. Both wild-type and mutant are capable optical silencers at low light intensities in mouse neurons in vitro and in vivo, while raACR offers a higher temporal resolution.


Asunto(s)
Channelrhodopsins , Luz , Neuronas , Optogenética , Optogenética/métodos , Animales , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Ratones , Neuronas/metabolismo , Neuronas/fisiología , Neuronas/efectos de la radiación , Aniones/metabolismo , Filogenia , Humanos
2.
Front Psychol ; 15: 1352320, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39205984

RESUMEN

Exposure to bright light can be visually aversive. This study explored the association between light aversion and various facets of impulsivity. A total of 1,245 participants completed the UPPS-Impulsive Behavior Scale to assess five facets of impulsivity. Additionally, participants responded to questions regarding their aversion to light (e.g., how aversive do you find bright light?). Spearman's correlation coefficients (rho) revealed that individuals who find light physically aversive, or who experience a negative physical response to exposure (e.g., nausea or headache) triggered by bright indoor light or sunlight, tend to act impulsively under extreme negative and positive affect. Individuals who experience a negative physical response to exposure display greater premeditation, indicating a higher likelihood of considering the potential consequences of their actions. Moreover, these individuals score lower on sensation-seeking, suggesting a reduced inclination to seek out thrilling or novel experiences. These results reveal a complex relationship between light aversion and impulsivity, where those who find light aversive tend to be less impulsive in general, but more impulsive under extreme positive or negative affect.

3.
Molecules ; 29(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39203048

RESUMEN

To synthesize an effective and versatile nano-platform serving as a promising carrier for controlled drug delivery, visible-light-induced diselenide-crosslinked polyurethane micelles were designed and prepared for ROS-triggered on-demand doxorubicin (DOX) release. A rationally designed amphiphilic block copolymer, poly(ethylene glycol)-b-poly(diselenolane diol-co-isophorone diisocyanate)-b-poly(ethylene glycol) (PEG-b-PUSe-b-PEG), which incorporates dangling diselenolane groups within the hydrophobic PU segments, was initially synthesized through the polycondensation reaction. In aqueous media, this type of amphiphilic block copolymer can self-assemble into micellar aggregates and encapsulate DOX within the micellar core, forming DOX-loaded micelles that are subsequently in situ core-crosslinked by diselenides via a visible-light-triggered metathesis reaction of Se-Se bonds. Compared with the non-crosslinked micelles (NCLMs), the as-prepared diselenide-crosslinked micelles (CLMs) exhibited a smaller particle size and improved colloidal stability. In vitro release studies have demonstrated suppressed drug release behavior for CLMs in physiological conditions, as compared to the NCLMs, whereas a burst release of DOX occurred upon exposure to an oxidation environment. Moreover, MTT assay results have revealed that the crosslinked polyurethane micelles displayed no significant cytotoxicity towards HeLa cells. Cellular uptake analyses have suggested the effective internalization of DOX-loaded crosslinked micelles and DOX release within cancer cells. These findings suggest that this kind of ROS-triggered reversibly crosslinked polyurethane micelles hold significant potential as a ROS-responsive drug delivery system.


Asunto(s)
Doxorrubicina , Luz , Micelas , Polímeros , Especies Reactivas de Oxígeno , Doxorrubicina/química , Doxorrubicina/farmacología , Especies Reactivas de Oxígeno/metabolismo , Humanos , Polímeros/química , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Portadores de Fármacos/química , Células HeLa , Polietilenglicoles/química , Supervivencia Celular/efectos de los fármacos , Tamaño de la Partícula
5.
J Fish Biol ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162132

RESUMEN

Triploidization influences various biological characteristics of fish, which is associated with reductions in the number of multiple cell types in different tissues/organs. Our behavioral analyses revealed that triploid Pacific bluefin tuna (Thunnus orientalis) larvae exhibit lower sensitivity to light compared to diploids. Furthermore, histological analyses revealed a reduction in the number of ganglion cells and an increase in their size in the retinas of triploid T. orientalis larvae. Our findings provide the first evidence indicating that triploidization reduces sensory perception during the larval stage of fish.

6.
J Pineal Res ; 76(2): e12936, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39041348

RESUMEN

Women typically sleep and wake earlier than men and have been shown to have earlier circadian timing relative to the light/dark cycle that synchronizes the clock. A potential mechanism for earlier timing in women is an altered response of the circadian system to evening light. We characterized individual-level dose-response curves for light-induced melatonin suppression using a within-subjects protocol. Fifty-six participants (29 women, 27 men; aged 18-30 years) were exposed to a range of light illuminances (10, 30, 50, 100, 200, 400, and 2000 lux) using melatonin suppression relative to a dim control (<1 lux) as a marker of light sensitivity. Women were free from hormonal contraception. To examine the potential influence of sex hormones, estradiol and progesterone was examined in women and testosterone was examined in a subset of men. Menstrual phase was monitored using self-reports and estradiol and progesterone levels. Women exhibited significantly greater melatonin suppression than men under the 400-lux and 2000-lux conditions, but not under lower light conditions (10-200 lux). Light sensitivity did not differ by menstrual phase, nor was it associated with levels of estradiol, progesterone, or testosterone, suggesting the sex differences in light sensitivity were not acutely driven by circulating levels of sex hormones. These results suggest that sex differences in circadian timing are not due to differences in the response to dim/moderate light exposures typically experienced in the evening. The finding of increased bright light sensitivity in women suggests that sex differences in circadian timing could plausibly instead be driven by a greater sensitivity to phase-advancing effects of bright morning light.


Asunto(s)
Ritmo Circadiano , Luz , Melatonina , Humanos , Femenino , Adulto , Ritmo Circadiano/fisiología , Adolescente , Adulto Joven , Masculino , Melatonina/metabolismo , Estradiol/sangre , Progesterona/sangre , Progesterona/metabolismo , Testosterona/sangre , Ciclo Menstrual/fisiología
7.
Vestn Oftalmol ; 140(2. Vyp. 2): 34-42, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38739129

RESUMEN

PURPOSE: This study analyzes changes in light sensitivity in each test point of the visual field in patients with different stages of glaucoma. MATERIAL AND METHODS: The data of a prospective analytical case-control study were analyzed. All patients underwent assessment of retinal light sensitivity and its variability in 54 points corresponding to the 24-2 program. Mean light sensitivity values were calculated in each point. Intergroup analysis was performed to evaluate changes in light sensitivity in each point. RESULTS: The range of light sensitivity decrease in the early glaucoma group compared to the control group was from 1.5 to 3.6 dB. The range of light sensitivity decrease in the moderate glaucoma group compared to the control group was from 2.1 to 11.5 dB, and compared to the early glaucoma group - from -0.9 to 7.9 dB. The most frequent decrease in light sensitivity was detected in the nasal sector and along the horizontal line in the upper half of the visual field. This trend persisted within the central 10 degrees of the visual field. The range of light sensitivity decrease in the advanced glaucoma group compared to the control group was from 14.1 to 28.0 dB, and compared to the early glaucoma group - from 11.35 to 26.08 dB, compared to the moderate glaucoma group - from 9.1 to 23.5 dB. The most frequent and severe decrease in light sensitivity was detected in the paracentral zone in the lower half of the visual field. CONCLUSION: The study analyzed the trends in the development of glaucoma from the early to the advanced stage. The most frequent and severe defect in light sensitivity in cases of verified advanced glaucoma was found in the lower half of the visual field. Points No. 32, 33 and 40 can be indicated as the area of interest in assessing the progression of glaucoma, as they were found to have the most profound changes in light sensitivity as glaucoma progressed.


Asunto(s)
Progresión de la Enfermedad , Glaucoma , Pruebas del Campo Visual , Campos Visuales , Humanos , Campos Visuales/fisiología , Glaucoma/fisiopatología , Glaucoma/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Pruebas del Campo Visual/métodos , Estudios Prospectivos , Anciano , Estudios de Casos y Controles , Luz
8.
Vestn Oftalmol ; 140(2. Vyp. 2): 116-122, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38739140

RESUMEN

PURPOSE: This study assesses the light sensitivity and its variability in each point of the visual field in patients without glaucoma and with different stages of glaucoma. MATERIAL AND METHODS: The data of a prospective analytical case-control study involving 500 patients were analyzed. The initial examination of all patients was performed using basic ophthalmological methods, including static perimetry. Retinal light sensitivity and its variability were assessed in 54 points corresponding to the Humphrey 24-2 program. Mean deviation and pattern standard deviation of light sensitivity were calculated for each point. RESULTS: The lowest light sensitivity values in patients with moderate glaucoma were found in the periphery of the nasal sector, at point No. 27 - 14.4 dB, and at points No. 24-26 along the horizontal axis from the nasal side - from 17.7 to 22.7 dB. The maximum variability of light sensitivity was found in the nasal sector on both sides of the horizontal line - from 10.7 to 11.5 dB. The average light sensitivity above the horizontal axis in patients with advanced glaucoma was 10.8 dB, which is 2 dB higher than in the lower half of the visual field - 8.8 dB. The highest light sensitivity values were found at points No. 24 - 17.7 dB and No. 31 - 16.78 dB, the lowest - at point No. 32 - 4.5 dB. The average variability values of light sensitivity in the upper half of the visual field were 9.6 dB, which is 1 dB less than in the lower half of the visual field - 10.6 dB. CONCLUSION: According to our data, points No. 32 and No. 40 are of particular interest in the diagnostic plan. In these loci, the highest light sensitivity values were determined in early and moderate glaucoma. However, the values in these points decrease significantly in advanced glaucoma. It can be assumed that changes in light sensitivity in these loci at the early stages of glaucoma may be a predictor of glaucoma progression.


Asunto(s)
Glaucoma , Retina , Pruebas del Campo Visual , Campos Visuales , Humanos , Campos Visuales/fisiología , Pruebas del Campo Visual/métodos , Glaucoma/fisiopatología , Glaucoma/diagnóstico , Persona de Mediana Edad , Masculino , Femenino , Retina/fisiopatología , Estudios Prospectivos , Adulto , Luz , Anciano , Umbral Sensorial/fisiología , Estudios de Casos y Controles , Reproducibilidad de los Resultados
9.
Neurol Ther ; 13(4): 1191-1201, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38819614

RESUMEN

INTRODUCTION: Vestibular migraine (VM) is a prevalent vestibular disorder characterized by episodic vertigo. However, the relationship between photophobia and visual triggers in VM remains unexplored. We investigated the correlation of photophobia during the VM attack with interictal photosensitivity and visually triggering dizziness in patients with VM. METHODS: We enrolled patients diagnosed with VM, with or without photophobia, across seven specialized vertigo and headache clinics in China. Healthy individuals were also included as a control group. Using a cross-sectional survey design, we collected data related to light intensity and dizziness frequency triggered by flicker, glare, and eyestrain using the Headache Triggers Sensitivity and Avoidance Questionnaire. RESULTS: A total of 366 patients were recruited. The photosensitivity and frequency of dizziness induced by flicker, glare, and eyestrain observed in patients with VM and photophobia were significantly elevated compared with those in patients without photophobia and control participants (P < 0.001). A significant positive correlation was observed between photosensitivity levels and dizziness frequency triggered by flicker, glare, and eyestrain in patients with VM and photophobia (P < 0.001). CONCLUSIONS: This study unequivocally established a positive association of ictal photophobia with interictal photosensitivity and visually triggering dizziness, strongly advocating the need for further research on exposure-based therapies for managing VM. CLINICAL TRIALS REGISTRATION: ClinicalTrial.gov Identifier, NCT04939922, retrospectively registered, 14th June 2021.

10.
Wellcome Open Res ; 9: 64, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716042

RESUMEN

Many people with bipolar disorder have disrupted circadian rhythms. This means that the timing of sleep and wake activities becomes out-of-sync with the standard 24-hour cycle. Circadian rhythms are strongly influenced by light levels and previous research suggests that people with bipolar disorder might have a heightened sensitivity to light, causing more circadian rhythm disruption, increasing the potential for triggering a mood switch into mania or depression. Lithium has been in clinical use for over 70 years and is acknowledged to be the most effective long-term treatment for bipolar disorder. Lithium has many reported actions in the body but the precise mechanism of action in bipolar disorder remains an active area of research. Central to this project is recent evidence that lithium may work by stabilising circadian rhythms of mood, cognition and rest/activity. Our primary hypothesis is that people with bipolar disorder have some pathophysiological change at the level of the retina which makes them hypersensitive to the visual and non-visual effects of light, and therefore more susceptible to circadian rhythm dysfunction. We additionally hypothesise that the mood-stabilising medication lithium is effective in bipolar disorder because it reduces this hypersensitivity, making individuals less vulnerable to light-induced circadian disruption. We will recruit 180 participants into the HELIOS-BD study. Over an 18-month period, we will assess visual and non-visual responses to light, as well as retinal microstructure, in people with bipolar disorder compared to healthy controls. Further, we will assess whether individuals with bipolar disorder who are being treated with lithium have less pronounced light responses and attenuated retinal changes compared to individuals with bipolar disorder not being treated with lithium. This study represents a comprehensive investigation of visual and non-visual light responses in a large bipolar disorder population, with great translational potential for patient stratification and treatment innovation.

11.
Int J Dermatol ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602089

RESUMEN

BACKGROUND: Erythropoietic protoporphyria (EPP) causes painful light sensitivity, limiting quality of life. Our objective was to develop and validate a wearable light exposure device and correlate measurements with light sensitivity in EPP to predict and prevent symptoms. METHODS: A wearable light dosimeter was developed to capture light doses of UVA, blue, and red wavelengths. A prospective observational pilot study was performed in which five EPP patients wore two light dosimeters for 3 weeks, one as a watch, and one as a shirt clip. RESULTS: Standard deviation (SD) increases from the mean in the daily blue light dose increased the odds ratio (OR) for symptom risk more than the self-reported outdoor time (OR 2.76 vs. 2.38) or other wavelengths, and a one SD increase from the mean in the daily blue light wristband device dose increased the OR for symptom risk more than the daily blue light shirt clip (OR 2.45 vs. 1.62). The area under the receiver operator curve for the blue light wristband dose was 0.78, suggesting 78% predictive accuracy. CONCLUSION: These data demonstrate that wearable blue light dosimetry worn as a wristband is a promising method for measuring light exposure and predicting and preventing symptoms in EPP.

12.
Evolution ; 78(7): 1237-1247, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558240

RESUMEN

Despite vision being an essential sense for many animals, the intuitively appealing notion that the visual system has been shaped by environmental light conditions is backed by insufficient evidence. Based on a comprehensive phylogenetic comparative analysis of birds, we investigate if exposure to different light conditions might have triggered evolutionary divergence in the visual system through pressures on light sensitivity, visual acuity, and neural processing capacity. Our analyses suggest that birds that have adopted nocturnal habits evolved eyes with larger corneal diameters and, to a lesser extent, longer axial length than diurnal species. However, we found no evidence that sensing and processing organs were selected together, as observed in diurnal birds. Rather than enlarging the processing centers, we found a tendency among nocturnal species to either reduce or maintain the size of the two main brain centers involved in vision-the optic tectum and the wulst. These results suggest a mosaic pattern of evolution, wherein optimization of the eye optics for efficient light capture in nocturnal species may have compromised visual acuity and central processing capacity.


Asunto(s)
Evolución Biológica , Aves , Visión Ocular , Animales , Aves/fisiología , Aves/genética , Luz , Filogenia , Agudeza Visual , Colículos Superiores/fisiología
13.
Food Res Int ; 181: 114110, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38448109

RESUMEN

Cashew nut testa (CNT) is an underutilized cashew by-product rich in polyphenols. The applications of CNT are limited due to its astringency, less solubility, and instability of polyphenols during the processing. Nanoencapsulation was used to overcome these limitations. ß-cyclodextrin alone and in combination with whey protein isolate (WPI) was used for nano-complex preparation. The WPI/CD-CNT nano-complex powder showed higher encapsulation efficiency (86.9%) and yield (70.5-80%) compared to CD-CNT powder. Both the spray-dried powders showed improved thermal stability, higher solubility (97%), less moisture content, and increased DPPH and ABTS radical scavenging activities indicating potential food and agricultural applications. In addition, the nano-complex powders showed a controlled release of core bio-actives under gastric and intestinal pH compared to the non-encapsulated CNT phenolic extract. Degradation kinetics studies of the CNT extract after thermal and light treatments were also discussed. Both the nano-complexes showed high stability under light and thermal treatment. The results suggest that valorization of CNT can be done through nano-complex preparation and WPI and ß-CD are efficient carrier materials for the encapsulation of polyphenols with potential applications in food and agriculture.


Asunto(s)
Anacardium , Antioxidantes , Proteína de Suero de Leche , Nueces , Polvos , Fenoles , Polifenoles , Extractos Vegetales
14.
Sleep ; 47(6)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38530635

RESUMEN

STUDY OBJECTIVES: Altered light sensitivity may be an underlying vulnerability for disrupted circadian photoentrainment. The photic information necessary for circadian photoentrainment is sent to the circadian clock from melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). The current study tested whether the responsivity of ipRGCs measured using the post-illumination pupil response (PIPR) was associated with circadian phase, sleep timing, and circadian alignment, and if these relationships varied by season or depression severity. METHODS: Adult participants (N = 323, agem = 40.5, agesd = 13.5) with varying depression severity were recruited during the summer (n = 154) and winter (n = 169) months. Light sensitivity was measured using the PIPR. Circadian phase was assessed using Dim Light Melatonin Onset (DLMO) on Friday evenings. Midsleep was measured using actigraphy. Circadian alignment was calculated as the DLMO-midsleep phase angle. Multilevel regression models covaried for age, gender, and time since wake of PIPR assessment. RESULTS: Greater light sensitivity was associated with later circadian phase in summer but not in winter (ß = 0.23; p = 0.03). Greater light sensitivity was associated with shorter DLMO-midsleep phase angles (ß = 0.20; p = 0.03) in minimal depression but not in moderate depression (SIGHSAD < 6.6; Johnson-Neyman region of significance). CONCLUSIONS: Light sensitivity measured by the PIPR was associated with circadian phase during the summer but not in winter, suggesting ipRGC functioning in humans may affect circadian entrainment when external zeitgebers are robust. Light sensitivity was associated with circadian alignment only in participants with minimal depression, suggesting circadian photoentrainment, a possible driver of mood, may be decreased in depression year-round, similar to decreased photoentrainment in winter.


Asunto(s)
Actigrafía , Ritmo Circadiano , Estaciones del Año , Sueño , Humanos , Masculino , Femenino , Ritmo Circadiano/fisiología , Adulto , Sueño/fisiología , Persona de Mediana Edad , Melatonina/metabolismo , Depresión/fisiopatología , Células Ganglionares de la Retina/fisiología , Luz , Pupila/fisiología , Pupila/efectos de la radiación
15.
Brain Inj ; 38(3): 177-185, 2024 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-38334039

RESUMEN

PURPOSE: Consistent with association between photophobia and headache, growing evidence suggests an underlying causal relationship between light sensitivity and central pain. We investigated whether an intervention to regulate light sensitivity by filtering only wavelengths causing difficulties for the specific individual could alleviate headaches/migraines resulting from traumatic brain injury (TBI). METHODS: Secondary data analysis of a clinical database including N = 392 military personnel (97% men, 3% women), ranging in age from 20 to 51 years, diagnosed with TBI, persistent headaches/migraines, and light sensitivity. The average elapsed time from TBI diagnosis to intervention was 3 years. Headache/migraine severity, frequency, medication use, and difficulties related to daily functioning were assessed pre and 4-12 weeks post-intervention with individualized spectral filters. RESULTS: Monthly migraine frequency decreased significantly from an average of 14.8 to 1.9, with 74% reporting no migraines post-intervention. Prescription and over-the-counter medication use decreased by more than 70%. Individuals also reported significant improvement in light sensitivity, headaches/migraine severity, and physical and perceptual symptoms. CONCLUSIONS: Wearing individualized spectral filters was associated with symptom relief, increased subjective quality of reported health and well-being, and decreased objective medication use for TBI-related persistent headaches/migraines. These results support a suggested relationship between dysregulated light sensitivity and central regulation of pain.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Trastornos Migrañosos , Personal Militar , Veteranos , Masculino , Humanos , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Fotofobia/terapia , Fotofobia/complicaciones , Cefalea , Trastornos Migrañosos/terapia , Lesiones Traumáticas del Encéfalo/complicaciones , Dolor
16.
Int Emerg Nurs ; 72: 101384, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37988775

RESUMEN

INTRODUCTION: Sensory overstimulation of autistic patients of all ages during an ED visit can ultimately lead to care escalation, but few studies have evaluated patient perspectives on improving the ED sensory experience across the age continuum. The purpose of this study was to explore patient-centered perspectives on reducing adult and pediatric autistic patients' sensory stimulation during an ED visit. METHODS: We used a qualitative descriptive design to explore how autistic patients experience sensory disruption and recommendations to improve care. Data were analyzed inductively using an overall categorization of 6 senses (visual, auditory, touch, smell, taste, and proprioception). RESULTS: Fourteen adults and 30 caregivers of children provided written responses to open-ended interview questions (n = 44). Participants suggested strategies to minimize the sensory disruption they experienced; however, an overarching recommendation was for clinicians to ask about their or their child's preferences before delivering care or services. CONCLUSION: Because people with autism are more likely to visit an ED than their neurotypical counterparts, ED clinicians should be proficient in "sensory-friendly care." A variety of evidence-based practical strategies and design approaches exist that can be leveraged to reduce the risk of care escalation; however, the most basic may be to prioritize asking patients and their caregivers about their preferences prior to providing care.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Adulto , Humanos , Niño , Trastorno del Espectro Autista/terapia , Cuidadores , Servicio de Urgencia en Hospital
17.
ACS Nano ; 17(24): 25552-25564, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38096149

RESUMEN

Photomemristors have been regarded as one of the most promising candidates for next-generation hardware-based neuromorphic computing due to their potentials of fast data transmission and low power consumption. However, intriguingly, so far, photomemristors seldom display truly nonvolatile memory characteristics with high light sensitivity. Herein, we demonstrate ultrasensitive photomemristors utilizing two-dimensional (2D) Ruddlesden-Popper (RP) perovskites with a highly polar donor-acceptor-type push-pull organic cation, 4-(5-(2-aminoethyl)thiophen-2-yl)benzonitrile+ (EATPCN+), as charge-trapping layers. High linearity and almost zero-decay retention are observed in (EATPCN)2PbI4 devices, which are very distinct from that of the traditional 2D RP perovskite devices consisting of nonpolar organic cations, such as phenethylamine+ (PEA+) and octylamine+ (OA+), and traditional 3D perovskite devices consisting of methylamine+ (MA+). The 2-fold advantages, including desirable spatial crystal arrangement and engineered energetic band alignment, clarify the mechanism of superior performance in (EATPCN)2PbI4 devices. The optimized (EATPCN)2PbI4 photomemristor also shows a memory window of 87.9 V and an on/off ratio of 106 with a retention time of at least 2.4 × 105 s and remains unchanged after >105 writing-reading-erasing-reading endurance cycles. Very low energy consumptions of 1.12 and 6 fJ for both light stimulation and the reading process of each status update are also demonstrated. The extremely low power consumption and high photoresponsivity were simultaneously achieved. The high photosensitivity surpasses that of a state-of-the-art commercial pulse energy meter by several orders of magnitude. With their outstanding linearity and retention, rabbit images have been rebuilt by (EATPCN)2PbI4 photomemristors, which truthfully render the image without fading over time. Finally, by utilizing the powerful ∼8 bits of nonvolatile potentiation and depression levels of (EATPCN)2PbI4 photomemristors, the accuracies of the recognition tasks of CIFAR-10 image classification and MNIST handwritten digit classification have reached 89% and 94.8%, respectively. This study represents the first report of utilizing a functional donor-acceptor type of organic cation in 2D RP perovskites for high-performance photomemristors with characteristics that are not found in current halide perovskites.

18.
Clocks Sleep ; 5(4): 651-666, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37987395

RESUMEN

It is well known that variations in light exposure during the day affect light sensitivity in the evening. More daylight reduces sensitivity, and less daylight increases it. On average days, we spend less time outdoors in winter and receive far less light than in summer. Therefore, it could be relevant when collecting research data on the non-image forming (NIF) effects of light on circadian rhythms and sleep. In fact, studies conducted only in winter may result in more pronounced NIF effects than in summer. Here, we systematically collected information on the extent to which studies on the NIF effects of evening light include information on season and/or light history. We found that more studies were conducted in winter than in summer and that reporting when a study was conducted or measuring individual light history is not currently a standard in sleep and circadian research. In addition, we sought to evaluate seasonal variations in a previously published dataset of 72 participants investigating circadian and sleep effects of evening light exposure in a laboratory protocol where daytime light history was not controlled. In this study, we selectively modulated melanopic irradiance at four different light levels (<90 lx). Here, we aimed to retrospectively evaluate seasonal variations in the responsiveness of the melanopsin system by combining all data sets in an exploratory manner. Our analyses suggest that light sensitivity is indeed reduced in summer compared to winter. Thus, to increase the reproducibility of NIF effects on sleep and circadian measures, we recommend an assessment of the light history and encourage standardization of reporting guidelines on the seasonal distribution of measurements.

19.
N Biotechnol ; 78: 76-83, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-37820830

RESUMEN

Antibody therapeutics show great potential to treat a variety of diseases. Often, the dose that can be safely administered is limited by side effects that arise from the interaction with the target outside the diseased tissue. Conditionally-active antibodies provide an additional layer of selectivity to improve safety. Distinct external stimuli or internal cues enable different control strategies and applications. However, current antibody masking strategies have low transferability across stimuli. Here we propose a versatile approach to conditionally mask antibody derivatives and its application to a single chain variable fragment (scFv) against a receptor expressed on cancer stem cells in several tumours. Our strategy relies on the site-specific conjugation of a polymer to an engineered cysteine residue through a chemically-synthesised linker that can be cleaved in response to the target stimulus. We show that the masking efficiency depends on the conjugation site and the size of the mask. An optimised mask decreases antigen binding by up to 20-fold and affinity can be fully recovered upon activation by exposure to light at 365 nm or by incubation with matrix metalloproteinases overexpressed in solid tumours. This approach opens up the possibility to rapidly engineer antibodies activatable with any internal or external stimulus.


Asunto(s)
Neoplasias , Anticuerpos de Cadena Única , Humanos , Cisteína/química
20.
Biology (Basel) ; 12(9)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37759614

RESUMEN

Circadian entrainment to the environmental day-night cycle is essential for the optimal use of environmental resources. In insects, opsin-based photoreception in the compound eye and ocelli and CRYPTOCHROME1 (CRY1) in circadian clock neurons are thought to be involved in sensing photic information, but the genetic regulation of circadian light entrainment in species without light-sensitive CRY1 remains unclear. To elucidate a possible CRY1-independent light transduction cascade, we analyzed light-induced gene expression through RNA-sequencing in Nasonia vitripennis. Entrained wasps were subjected to a light pulse in the subjective night to reset the circadian clock, and light-induced changes in gene expression were characterized at four different time points in wasp heads. We used co-expression, functional annotation, and transcription factor binding motif analyses to gain insight into the molecular pathways in response to acute light stimulus and to form hypotheses about the circadian light-resetting pathway. Maximal gene induction was found after 2 h of light stimulation (1432 genes), and this included the opsin gene opblue and the core clock genes cry2 and npas2. Pathway and cluster analyses revealed light activation of glutamatergic and GABA-ergic neurotransmission, including CREB and AP-1 transcription pathway signaling. This suggests that circadian photic entrainment in Nasonia may require pathways that are similar to those in mammals. We propose a model for hymenopteran circadian light-resetting that involves opsin-based photoreception, glutamatergic neurotransmission, and gene induction of cry2 and npas2 to reset the circadian clock.

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