Portable and Rapid Dual-Biomarker Detection Using Solution-Gated Graphene Field Transistors in the Accurate Diagnosis of Prostate Cancer.

Prostate-specific antigen (PSA) is the common serum-relevant biomarker for early prostate cancer (PCa) detection in clinical diagnosis. However, it is difficult to accurately diagnose PCa in the early stage due to the low specificity of PSA. Herein, a new solution-gated graphene field transistor (SGGT) biosensor with dual-gate for dual-biomarker detection is designed. The sensing mechanism is that the designed aptamers immobilized on the surface of the gate electrodes can capture PSA and sarcosine (SAR) biomolecules and induce the capacitance changes of the electric double layers of SGGT. The limit of detections of PSA and SAR biomarkers can reach 0.01 fg mL-1 , which is three-to-four orders of magnitude lower than previously reported assays. The detection time of PSA and SAR is ≈4.5 and ≈13 min, which is significantly faster than the detection time (1-2 h) of conventional methods. The clinical serum samples testing demonstrates that the biosensor can distinguish the PCa patients from the control group and the diagnosis accuracy can reach 100%. The SGGT biosensor can be integrated into the portable platform and the diagnostic results can directly display on the smartphone/Pad. Therefore, the integrated portable platform of the biosensor can distinguish cancer types through the dual-biomarker detection.

The osteogenic effects of sappanchalcone in vitro and in vivo.

BACKGROUND AND OBJECTIVES: The utilization of natural products to enhance the function of periodontal ligament cells (PDLCs) has emerged as a popular area of research. Recent investigations have demonstrated that sappanchalcone (SC) possesses pharmacological properties such as anti-inflammatory and osteoprotective effects. This study aims to explore the impact of SC on the in vivo and in vitro osteogenic differentiation ability of PDLCs. MATERIALS: Cell proliferation was quantified using the CCK-8 assay, while gene expression levels were assessed through qRT-PCR analysis. Osteoblast differentiation capacity was evaluated by employing Alizarin red staining (ARS), alkaline phosphatase (ALP) staining and western blot (WB) analysis. A rat model of periodontitis was established utilizing the tether-wire method. Micro-CT imaging and hematoxylin and eosin (HE) staining were employed to evaluate alveolar bone resorption. Masson's trichrome staining was utilized to observe fiber alignment, whereas immunohistochemistry (IHC) techniques were applied for detecting osteogenic and inflammatory factors. RESULTS: The results from the CCK-8 assay indicate no observed cytotoxicity for concentrations of 1, 5, or 10 nM for SC treatment (p < .05), while qRT-PCR analysis demonstrates a significant decrease in inflammatory factors such as MMP-1 and IL-6 with treatment by SC (p < .05). Additionally, western blotting reveals an increase in protein expression levels of Runx2 and OPN within PDLCs treated with SC compared to control groups (p < .05), which is further supported by ARS and ALP staining indicating an increase in mineralized nodules formation along with elevated ALP content within these cells following treatment with this compound (p < .05). Finally, both HE staining as well as micro-CT imaging suggest potential benefits associated with using this compound including slowing alveolar bone resorption while simultaneously promoting junctional epithelium proliferation. CONCLUSIONS: Our in vitro and in vivo findings suggest that SC can effectively enhance the inflammatory response of PDLCs and promote their osteogenic differentiation ability under inflammatory conditions, indicating its potential as a promising therapeutic agent for improving periodontal inflammation and bone formation.

Expression of the transcription factor Klf6 by thymic epithelial cells is required for thymus development.

Thymic epithelial cells (TEC) control T cell development and play essential roles in establishing self-tolerance. By using Foxn1-Cre-driven ablation of Klf6 gene in TEC, we identified Klf6 as a critical factor in TEC development. Klf6 deficiency resulted in a hypoplastic thymus-evident from fetal stages into adulthood-in which a dramatic increase in the frequency of apoptotic TEC was observed. Among cortical TEC (cTEC), a previously unreported cTEC population expressing the transcription factor Sox10 was relatively expanded. Within medullary TEC (mTEC), mTEC I and Tuft-like mTEC IV were disproportionately decreased. Klf6 deficiency altered chromatin accessibility and affected TEC chromatin configuration. Consistent with these defects, naïve conventional T cells and invariant natural killer T cells were reduced in the spleen. Late stages of T cell receptor-dependent selection of thymocytes were affected, and mice exhibited autoimmunity. Thus, Klf6 has a prosurvival role and affects the development of specific TEC subsets contributing to thymic function.

Ion incorporation into bone grafting materials.

The use of biomaterials in regenerative medicine has expanded to treat various disorders caused by trauma or disease in orthopedics and dentistry. However, the treatment of large and complex bone defects presents a challenge, leading to a pressing need for optimized biomaterials for bone repair. Recent advances in chemical sciences have enabled the incorporation of therapeutic ions into bone grafts to enhance their performance. These ions, such as strontium (for bone regeneration/osteoporosis), copper (for angiogenesis), boron (for bone growth), iron (for chemotaxis), cobalt (for B12 synthesis), lithium (for osteogenesis/cementogenesis), silver (for antibacterial resistance), and magnesium (for bone and cartilage regeneration), among others (e.g., zinc, sodium, and silica), have been studied extensively. This review aims to provide a comprehensive overview of current knowledge and recent developments in ion incorporation into biomaterials for bone and periodontal tissue repair. It also discusses recently developed biomaterials from a basic design and clinical application perspective. Additionally, the review highlights the importance of precise ion introduction into biomaterials to address existing limitations and challenges in combination therapies. Future prospects and opportunities for the development and optimization of biomaterials for bone tissue engineering are emphasized.

The Effect of an Extract of Sappanwood, Protosappanin A and Protosappanin B on Osteogenesis in Periodontitis.

BACKGROUND: Sappanwood is widely used in the prevention and treatment in diseases due to its ability to seal blood vessels, dissipate stasis, and relieve pain. Important monomer components of sappanwood, Protosappanin A (PA) and Protosappanin B (PB) have anti-tumour and antimicrobial medicinal properties. This study investigated the anti-inflammatory and osteogenic differentiation effects of a crude extract of Sappanwood (ESP), PA and PB against periodontitis in periodontal ligament stem cells (PDLSCs). METHODS: Oil Red O staining was used to assess the ability of adipocytes to differentiate. Alizarin Red staining was used to assess the capacity to differentiate into osteoblasts. Third-passage PDLSCs were grown in either basic medium alone or basic media with varying doses of ESP (0.0625 mg/mL, 0.03125 mg/mL and 0.125 mg/mL), PA and PB (2.5 µM, 5 µM, 10 µM). The CCK-8 assay was used to measure cell proliferation. Real Time PCR (RT-qPCR) and Enzyme-Linked Immunosorbnent Assay (ELISA) assay were used to measure gene expression. The capacity to differentiate into osteoblasts was evaluated using Alizarin Red staining, and Alkaline Phosphatase (ALP) staining and activity. RESULTS: The development of lipid droplets and mineralized nodules was examined using Oil Red O staining and Alizarin Red staining. Flow cytometry revealed that PDLSCs were CD29 (98.23%) and CD44 (98.81%) positive, but CD34 (0.16%) and CD45 (0.09%) negative. CCK-8 assay showed that ESP at three concentrations (0.03125 mg/mL, 0.0625 mg/mL and 0.125 mg/mL) and 2.5 µM, 5 µM and 10 µM PA and PB had no cytotoxicity at 5 and 7 days (p < 0.05). qRT-PCR and ELISA assay indicated that ESP, PA and PB downregulated the inflammatory cytokines IL-8, IL-6, IL-1ß, IL-10 and IL-4 and elevated the mRNA expression of osteogenesis cytokines RUNX2 , OSX and OCN in PDLSCs (p < 0.05). Alizarin red staining, and ALP staining and activity showed that ESP, PA and PB increased mineralized nodules and the ALP content of in PDLSCs (p < 0.05). CONCLUSIONS: ESP, PA and PB can reduce the inflammatory response and amplify the osteogenic differentiation of PDLSCs. Therefore, ESP, PA and PB may have potential pharmacological effects in controlling the progression of periodontitis and promoting periodontal tissue regeneration.

Design and Construction of Enzyme-Based Electrochemical Gas Sensors.

The demand for the ubiquitous detection of gases in complex environments is driving the design of highly specific gas sensors for the development of the Internet of Things, such as indoor air quality testing, human exhaled disease detection, monitoring gas emissions, etc. The interaction between analytes and bioreceptors can described as a "lock-and-key", in which the specific catalysis between enzymes and gas molecules provides a new paradigm for the construction of high-sensitivity and -specificity gas sensors. The electrochemical method has been widely used in gas detection and in the design and construction of enzyme-based electrochemical gas sensors, in which the specificity of an enzyme to a substrate is determined by a specific functional domain or recognition interface, which is the active site of the enzyme that can specifically catalyze the gas reaction, and the electrode-solution interface, where the chemical reaction occurs, respectively. As a result, the engineering design of the enzyme electrode interface is crucial in the process of designing and constructing enzyme-based electrochemical gas sensors. In this review, we summarize the design of enzyme-based electrochemical gas sensors. We particularly focus on the main concepts of enzyme electrodes and the selection and design of materials, as well as the immobilization of enzymes and construction methods. Furthermore, we discuss the fundamental factors that affect electron transfer at the enzyme electrode interface for electrochemical gas sensors and the challenges and opportunities related to the design and construction of these sensors.

Pulmonary papillary adenoma with malignant potential: a case report and literature review.

BACKGROUND: Pulmonary papillary adenoma is a rare benign tumor in the periphery of the lung. We report a 66-year-old female patient with a tumor in the lower lobe of the right lung and present the clinicopathological features and review the literature. CASE PRESENTATION: A tumor in the lower lobe of the right lung was found incidentally on chest X-ray during the physical examination of the patient, and the patient occasionally had a dry cough that was not treated. The tumor was clearly demarcated and lobulated on CT scan. After 2 years of follow-up, the boundary of the tumor was still clear, with more lobulations and the enhanced scan showed uniform enhancement. Grossly, the tumor had a granular cut surface and was easy to fall off, which was helpful for the diagnosis of papillary adenoma during intraoperative frozen examination. Under the microscope, most areas of the tumor had the typical morphological structure of papillary adenoma. However, the tumor locally protruded into the surrounding lung tissue, accompanied by crowded cells and high cell proliferation index. It was suggested that this case of papillary adenoma had malignant potential and needed active intervention and treatment. CONCLUSION: Pulmonary papillary adenoma is a rare epithelial tumor with malignant potential. Surgical treatment should be performed as soon as possible after diagnosis to prevent malignant transformation.

A Specific pSer/Thr-Pro Motif Generates Interdomain Communication Bifurcations of Two Modes of Pin1 in Solution Nuclear Magnetic Resonance.

Peptides mediate the interdomain communication of Pin1 (peptidyl-prolyl cis-trans isomerase) and can regulate its conformation and biochemical functions, providing an idea for drug design using Pin1. Two template peptide sequences have been widely used in the extended or compact state of Pin1 (Cdc25C, E-Q-P-L-pT-P-V-T-D-L; Pintide, W-F-Y-pS-P-R). The way in which specific pSer/Thr-Pro peptides regulate interdomain communication to achieve the opposite state is not clear. In this study, we subdivided the sequence composition of eight types of modified peptides and investigated the interaction with Pin1 by solution nuclear magnetic resonance and molecular dynamics. Demonstrating sequence dependence on the pSer-Pro or pThr-Pro motif and different residues in anchoring the WW domain, the Pin peptide (Pintide, PintideT, Pin25C, and Pin25CT) transmits this concentration accumulation to the PPIase domain, thus exhibiting two anchoring tendencies. However, the Cdc peptide (Cdc25C, Cdc25CS, Cdctide, and CdctideS) has a low binding energy that makes it difficult for the conformation to reach a steady state. In addition, Pin1 is influenced by both compact and extended states, regulated precisely by the sequence as well as by threonine or serine. These results provide new insight into the interdomain communication of Pin1 via pSer/Thr-Pro peptide binding.

Analysis of Processing Effects on Glucosinolate Profiles in Red Cabbage by LC-MS/MS in Multiple Reaction Monitoring Mode.

Red cabbage (Brassica oleracea L. var. capitata) continues to receive increasing attention on its health-promoting properties because of its high glucosinolate content. Glucosinolates are an unstable active substance; however, there are few studies on their changes in different cooking processes. In this study, we investigated the effects of processing methods (boiling, steaming, microwave heating, frying, stir-frying) and boiling time on glucosinolates in red cabbage. Ten glucosinolates, including 4-methoxyglucobrassicin, neoglucobrassicin, glucoalyssin, glucobrassicin, glucoraphanin, glucoiberin, progoitrin, gluconapin and sinigrin, in red cabbage were detected. Decreases of 32.36%, 24.83%, 25.27%, 81.11% and 84.29% for total glucosinolates were observed after boiling, microwaving, steaming, frying and stir-frying. Indole glucosinolates were more efficiently lost compared to aliphatic glucosinolates after boiling, while microwaving, steaming, frying and stir-frying also resulted in a greater reduction in indole glucosinolates than aliphatic glucosinolates. Glucoalyssin, glucoerucin and sinigrin were more thermal sensitive than other glucosinolates. It was confirmed that microwaving and steaming retained higher levels of glucosinolates than other methods and may be better for cooking red cabbage.

Improvement of simulating sub-daily hydrological impacts of rainwater harvesting for landscape irrigation with rain barrels/cisterns in the SWAT model.

Rain barrels/cisterns, a popular type of low impact development (LID) practice, can restore urban hydrological processes and decrease municipal water use by harvesting roof runoff for later use, such as landscape irrigation. However, tools to assist decision makers in creating efficient rainwater harvesting and reuse strategies are limited. This study improved the Soil and Water Assessment Tool (SWAT) in simulating the subdaily hydrological impacts of rainwater harvesting for landscape irrigation with rain barrels/cisterns, including the simulation of rainwater harvesting with rain barrels/cisterns, rainwater reuse for auto landscape irrigation, evapotranspiration, initial abstraction, impervious area, soil profile, and lawn management operation. The improved SWAT was applied in the urbanized Brentwood watershed (Austin, TX) to evaluate its applicability and investigate the impacts of rainwater harvesting and reuse strategies on the reductions and reduction efficiencies (reductions per volume of rain barrels/cisterns implemented) of field scale runoff (peak and depth) and watershed scale streamflow (peak and volume) for two storm events. Scenarios explored included different sizes of rain barrels/cisterns, percentages of rooftop areas with rain barrels/cisterns implemented, auto landscape irrigation rates, and landscape irrigation starting times. The performance of rainwater harvesting and reuse strategies, which is determined by features of fields, watersheds, and storm events, varied for different reduction goals (streamflow or runoff, and peak or depth/volume). For instance, the scenario with rain barrel/cistern sizes of 7.5 mm (design runoff depth from treated roof area) and the scenario with 10% of suitable area implemented with rain barrels/cisterns provided the highest peak streamflow reduction efficiency and total streamflow volume reduction efficiency at the watershed scale, respectively for the smaller storm event. To achieve sustainable urban stormwater management, the improved SWAT model has enhanced capability to help stakeholders create efficient rainwater harvesting and reuse strategies to reduce field scale runoff and watershed scale streamflow.

Key Markers and Epigenetic Modifications of Dental-Derived Mesenchymal Stromal Cells.

As a novel research hotspot in tissue regeneration, dental-derived mesenchymal stromal cells (MSCs) are famous for their accessibility, multipotent differentiation ability, and high proliferation. However, cellular heterogeneity is a major obstacle to the clinical application of dental-derived MSCs. Here, we reviewed the heterogeneity of dental-derived MSCs firstly and then discussed the key markers and epigenetic modifications related to the proliferation, differentiation, immunomodulation, and aging of dental-derived MSCs. These messages help to control the composition and function of dental-derived MSCs and thus accelerate the translation of cell therapy into clinical practice.

Identification of α-glucosidase inhibitors from Cortex Lycii based on a bioactivity-labeling high-resolution mass spectrometry-metabolomics investigation.

Cortex Lycii, as a kind of traditional Chinese medicines, have shown prospects in the prevention of diabetes and its complications. However, there is comparatively little information regarding the characterization of potentially hypoglycemic compounds derived from Cortex Lycii. In this study, we performed a global non-selective investigation of α-glucosidase inhibitors in Cortex Lycii based on a bioactivity-labeling high-resolution mass spectrometry-metabolomics method. Samples of Cortex Lycii were collected from different Chinese provinces and their ethyl acetate extracts were analyzed using an in vitro α-glucosidase inhibition assay for bioactivity-labeling. The ethyl acetate extracts were also subjected to liquid chromatography-mass spectrometry analysis and multivariate data analysis was subsequently conducted to identify correlations between the bioactivity measured from the enzyme-involved test and the profiles obtained based on high-resolution mass spectrometry. The variables contributing significantly to the separation of the more-active from the less-active samples were considered to indicate the potential target ions of active compounds. MS/MS fragment patterns and nuclear magnetic resonance analyses were used to identify the potential target ions. The developed platform mentioned above facilitated rapid identification of four α-glucosidase inhibitors, namely, N-p-trans-coumaroyltyramine (1), N-trans-caffeoyl-tyramine (2), (9R,10E,12Z)-9-hydroxy-10,12-octadecadienoic acid (3a), and (9S,10E,12Z)-9-hydroxy-10,12-octadecadienoic acid (3b) from Cortex Lycii. The α-glucosidase inhibitory activities of compounds 3a and 3b with IC50 values of 1.0413±0.0551 and 1.0423±0.0049 mM, respectively, are reported here for the first time. Enzyme kinetics revealed that both 3a and 3b were non-competitive inhibitors of α-glucosidase, with Ki values of 2.20 and 2.24 mM, respectively. In short, the presented work identified compounds 3a and 3b as potential α-glucosidase inhibitors with higher inhibitory activity and a different mode of inhibition compared to the standard α-glucosidase inhibitor, acarbose. The integrated approach adopted in this study can be extended as a normalized procedure to rapidly identify active compounds, even from complex extracts, and can readily be adapted for the study of other natural products.

Evaluation of the effectiveness of green infrastructure on hydrology and water quality in a combined sewer overflow community.

Evaluation of the effectiveness of green infrastructure (GI) practices on improving site hydrology and water quality and their associated cost could provide valuable information for decision makers when creating development/re-development strategies. In this study, a watershed scale rainfall-runoff model (the Long-Term Hydrologic Impact Analysis - Low Impact Development model, the L-THIA-LID 2.1 model) was enhanced to improve its simulation of urban water management practices including GI practices. The enhanced model (L-THIA-LID 2.2) is capable of: simulating in more detail impervious surfaces including sidewalks, roads, driveways, and parking lots; conducting cost calculations for converting these impervious surfaces to porous pavements; and, selecting suitable areas for bioretention in the study area. The effectiveness of GI practices on improving hydrology and water quality in a combined sewer overflow urban watershed-the Darst Sewershed in the City of Peoria, IL-was examined in eleven simulation scenarios using 8 practices. The total cost and the cost effectiveness for each scenario considering a 20-year practice lifetime were calculated. Results showed: combined implementation of GI practices performed better than applying individual practices alone; adoption levels and combinations of GI practices could potentially reduce runoff volume by 0.2-23.5%, TSS by 0.18-30.8%, TN by 0.2-27.9%, and TP by 0.2 to 28.1%; adding more practices did not necessarily achieve substantial runoff and pollutant reductions based on site characteristics; the most cost-effective scenario out of eleven considered had an associated cost of $9.21 to achieve 1 m3 runoff reduction per year and $119 to achieve 1 kg TSS reduction per year assuming residents' cooperation in implementing GI practices on their properties; adoption of GI practices on all possible areas could potentially achieve the greatest runoff and pollutant reduction, but would not be the most cost-effective option. This enhanced model can be applied to different locations to support assessing the beneficial uses of GI practices.

Green infrastructure practices simulation of the impacts of land use on surface runoff: Case study in Ecorse River watershed, Michigan.

As an urban fringe district, the Ecorse River watershed is faced with increased impervious area caused by urban expansion. Effects of Green Infrastructure (GI) practice implementation were simulated with the Long-Term Hydrologic Impact Assessment-Low Impact Development 2.1 model (L-THIA-LID 2.1). Suitable locations of each GI practice were identified, based on construction condition requirements and demand on GI practices in the study area. Using the data of 2011, various GI practice combination scenarios were explored according to the cost-efficiency of each GI practice. GI practice implementation scenarios in 2050 were also simulated based on projected land use and rainfall data. Results show that grassed swales, rain barrels (residential areas) and dry ponds were the top three most cost-efficient GI practices, with the cost at $1.5/m³/yr, $3.0/m³/yr and $3.4/m³/yr, respectively. Green roofs with rain cisterns (industrial and commercial area) were the most expensive GI practices, with the cost at $92.9/m³/yr. With the increase of investment in GI practices, the changing curves of the annual runoff volume, Total Nitrogen (TN) load and Total Phosphorus (TP) load reduction ratios match the law of diminishing marginal utility. The scenario with grassed swales, rain barrels, dry ponds and porous pavement would be the most cost-efficient scenario for runoff water quantity reduction. In addition, the scenario with additional wet ponds would be the most cost-efficient one for TN load and TP load reduction. GI practices in each scenario for expected 2050 conditions show better effectiveness on water quantity and quality management.

High frame-rate computational ghost imaging system using an optical fiber phased array and a low-pixel APD array.

To obtain a high imaging frame rate, a computational ghost imaging system scheme is proposed based on optical fiber phased array (OFPA). Through high-speed electro-optic modulators, the randomly modulated OFPA can provide much faster speckle projection, which can be precomputed according to the geometry of the fiber array and the known phases for modulation. Receiving the signal light with a low-pixel APD array can effectively decrease the requirement on sampling quantity and computation complexity owing to the reduced data dimensionality while avoiding the image aliasing due to the spatial periodicity of the speckles. The results of analysis and simulation show that the frame rate of the proposed imaging system can be significantly improved compared with traditional systems.

The effects of team reflexivity on psychological well-being in manufacturing teams.

While the impact of team reflexivity (a.k.a. after-event-reviews, team debriefs) on team performance has been widely examined, we know little about its implications on other team outcomes such as member well-being. Drawing from prior team reflexivity research, we propose that reflexivity-related team processes reduce demands, and enhance control and support. Given the centrality of these factors to work-based strain, we posit that team reflexivity, by affecting these factors, may have beneficial implications on 3 core dimensions of employee burnout, namely exhaustion, cynicism, and inefficacy (reduced personal accomplishment). Using a sample of 469 unskilled manufacturing workers employed in 73 production teams in a Southern Chinese factory, we implemented a time lagged, quasi-field experiment, with half of the teams trained in and executing an end-of-shift team debriefing, and the other half assigned to a control condition and undergoing periodic postshift team-building exercises. Our findings largely supported our hypotheses, demonstrating that relative to team members assigned to the control condition, those assigned to the reflexivity condition experienced a significant improvement in all 3 burnout dimensions over time. These effects were mediated by control and support (but not demands) and amplified as a function of team longevity. (PsycINFO Database Record

Effects of preparation methods on potato microstructure and digestibility: An in vitro study.

The effects of preparation method (boiled, cooled, and reheated) on the structural characteristics and in vitro digestibility of potato were investigated. The highest equilibrium starch hydrolysis was obtained after boiling (82.21%), followed by reheating (66.98%) and cooling (54.31%). The potato after cooling treatment exhibited a narrower melting temperature range and a higher melting enthalpy compared with the potatoes after boiling and the microwave reheating. X-ray diffraction patterns revealed that the relative crystallinity of the cooled potato was higher than those of the reheated and boiled potatoes, consistent with the results in melting enthalpy. Moreover, compared with the boiled potato, a large number of wrinkles were observed on the surface of the cooled potato, whereas after microwave reheating, larger clearances of starch granule regions were found. This study demonstrated that cooling and microwave reheating significantly affected the potato's microstructure and digestibility and were suggested as alternative choices to prepare potato dishes.

Direct activation of sleep-promoting VLPO neurons by volatile anesthetics contributes to anesthetic hypnosis.

BACKGROUND: Despite seventeen decades of continuous clinical use, the neuronal mechanisms through which volatile anesthetics act to produce unconsciousness remain obscure. One emerging possibility is that anesthetics exert their hypnotic effects by hijacking endogenous arousal circuits. A key sleep-promoting component of this circuitry is the ventrolateral preoptic nucleus (VLPO), a hypothalamic region containing both state-independent neurons and neurons that preferentially fire during natural sleep. RESULTS: Using c-Fos immunohistochemistry as a biomarker for antecedent neuronal activity, we show that isoflurane and halothane increase the number of active neurons in the VLPO, but only when mice are sedated or unconscious. Destroying VLPO neurons produces an acute resistance to isoflurane-induced hypnosis. Electrophysiological studies prove that the neurons depolarized by isoflurane belong to the subpopulation of VLPO neurons responsible for promoting natural sleep, whereas neighboring non-sleep-active VLPO neurons are unaffected by isoflurane. Finally, we show that this anesthetic-induced depolarization is not solely due to a presynaptic inhibition of wake-active neurons as previously hypothesized but rather is due to a direct postsynaptic effect on VLPO neurons themselves arising from the closing of a background potassium conductance. CONCLUSIONS: Cumulatively, this work demonstrates that anesthetics are capable of directly activating endogenous sleep-promoting networks and that such actions contribute to their hypnotic properties.

Accumulation of an antidepressant in vesiculogenic membranes of yeast cells triggers autophagy.

Many antidepressants are cationic amphipaths, which spontaneously accumulate in natural or reconstituted membranes in the absence of their specific protein targets. However, the clinical relevance of cellular membrane accumulation by antidepressants in the human brain is unknown and hotly debated. Here we take a novel, evolutionarily informed approach to studying the effects of the selective-serotonin reuptake inhibitor sertraline/Zoloft® on cell physiology in the model eukaryote Saccharomyces cerevisiae (budding yeast), which lacks a serotonin transporter entirely. We biochemically and pharmacologically characterized cellular uptake and subcellular distribution of radiolabeled sertraline, and in parallel performed a quantitative ultrastructural analysis of organellar membrane homeostasis in untreated vs. sertraline-treated cells. These experiments have revealed that sertraline enters yeast cells and then reshapes vesiculogenic membranes by a complex process. Internalization of the neutral species proceeds by simple diffusion, is accelerated by proton motive forces generated by the vacuolar H(+)-ATPase, but is counteracted by energy-dependent xenobiotic efflux pumps. At equilibrium, a small fraction (10-15%) of reprotonated sertraline is soluble while the bulk (90-85%) partitions into organellar membranes by adsorption to interfacial anionic sites or by intercalation into the hydrophobic phase of the bilayer. Asymmetric accumulation of sertraline in vesiculogenic membranes leads to local membrane curvature stresses that trigger an adaptive autophagic response. In mutants with altered clathrin function, this adaptive response is associated with increased lipid droplet formation. Our data not only support the notion of a serotonin transporter-independent component of antidepressant function, but also enable a conceptual framework for characterizing the physiological states associated with chronic but not acute antidepressant administration in a model eukaryote.