RESUMEN
Purpose: To evaluate the effect of lurasidone on a new, patient Life Engagement scale in schizophrenia. Patients and Methods: This post-hoc analysis included participants (ages 18 to 74) diagnosed with schizophrenia who were randomized to lurasidone (40 mg/day) or placebo in a 6-week double-blind efficacy study and those who continued in a subsequent 12-week open-label extension study during which patients received either 40 or 80/mg day lurasidone (flexibly dosed). Change in life engagement was measured using the Positive and Negative Syndrome Scale (PANSS) 11-item Life Engagement subscale score, and individual subscale items, at week 6 during the double-blind phase and extension phase week 12 during the open-label extension phase. Results: Analysis focused on 478 subjects randomized to lurasidone or placebo during the 6-week trial, and 146 who received lurasidone during the extension phase. During the 6-week trial, there was a significantly greater change on the PANSS11 Life Engagement subscale score from baseline to week 6 in the lurasidone group compared to the placebo group (mean changes of -6.4 and -4.8, respectively, p = 0.006; effect size = 0.27). Further improvement was evident during the extension phase for patients who received lurasidone in both phases, with a mean change from double-blind baseline to week 12 of the open-label treatment phase of -10.1 on in PANSS11 Life Engagement subscale. Conclusion: This post-hoc analysis suggests that lurasidone may improve life engagement in patients with schizophrenia, a meaningful outcome from patients' perspective. Further studies are needed to confirm this effect. Eudract Number: Trial registration: EudraCT Numbers: 2016-000060-42; 2016-000061-23.
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Vitamin C plays important roles as a cofactor in many enzymatic reactions and as an antioxidant against oxidative stress. As some mammals including humans cannot synthesize vitamin C de novo from glucose, its uptake from dietary sources is essential, and is mediated by the sodium-dependent vitamin C transporter 1 (SVCT1). Despite its physiological significance in maintaining vitamin C homeostasis, the structural basis of the substrate transport mechanism remained unclear. Here, we report the cryo-EM structures of human SVCT1 in different states at 2.5-3.5 Å resolutions. The binding manner of vitamin C together with two sodium ions reveals the counter ion-dependent substrate recognition mechanism. Furthermore, comparisons of the inward-open and occluded structures support a transport mechanism combining elevator and distinct rotational motions. Our results demonstrate the molecular mechanism of vitamin C transport with its underlying conformational cycle, potentially leading to future industrial and medical applications.
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Ácido Ascórbico , Microscopía por Crioelectrón , Transportadores de Sodio Acoplados a la Vitamina C , Humanos , Transportadores de Sodio Acoplados a la Vitamina C/metabolismo , Transportadores de Sodio Acoplados a la Vitamina C/química , Transportadores de Sodio Acoplados a la Vitamina C/genética , Ácido Ascórbico/metabolismo , Ácido Ascórbico/química , Transporte Biológico , Sodio/metabolismo , Modelos Moleculares , Multimerización de Proteína , Unión Proteica , Células HEK293 , Conformación ProteicaRESUMEN
Pyroglutamylated RF-amide peptide (QRFP) is a peptide hormone with a C-terminal RF-amide motif. QRFP selectively activates a class A G-protein-coupled receptor (GPCR) GPR103 to exert various physiological functions such as energy metabolism and appetite regulation. Here, we report the cryo-electron microscopy structure of the QRFP26-GPR103-Gq complex at 3.19 Å resolution. QRFP26 adopts an extended structure bearing no secondary structure, with its N-terminal and C-terminal sides recognized by extracellular and transmembrane domains of GPR103 respectively. This movement, reminiscent of class B1 GPCRs except for orientation and structure of the ligand, is critical for the high-affinity binding and receptor specificity of QRFP26. Mutagenesis experiments validate the functional importance of the binding mode of QRFP26 by GPR103. Structural comparisons with closely related receptors, including RY-amide peptide-recognizing GPCRs, revealed conserved and diversified peptide recognition mechanisms, providing profound insights into the biological significance of RF-amide peptides. Collectively, this study not only advances our understanding of GPCR-ligand interactions, but also paves the way for the development of novel therapeutics targeting metabolic and appetite disorders and emergency medical care.
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Microscopía por Crioelectrón , Receptores Acoplados a Proteínas G , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/química , Humanos , Células HEK293 , Unión Proteica , Ligandos , Péptidos y Proteínas de Señalización IntercelularRESUMEN
G-protein-coupled receptors (GPCRs) constitute a prominent superfamily in humans and are categorized into six classes (A-F) that play indispensable roles in cellular communication and therapeutics. Nonetheless, their structural comprehension has been limited by challenges in high-resolution data acquisition. This review highlights the transformative impact of cryogenic electron microscopy (cryo-EM) on the structural determinations of GPCR-G-protein complexes. Specific technologies, such as nanobodies and mini-G-proteins, stabilize complexes and facilitate structural determination. We discuss the structural alterations upon receptor activation in different GPCR classes, revealing their diverse mechanisms. This review highlights the robust foundation for comprehending GPCR function and pave the way for future breakthroughs in drug discovery and therapeutic targeting.
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Microscopía por Crioelectrón , Receptores Acoplados a Proteínas G , Microscopía por Crioelectrón/métodos , Humanos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/química , Conformación Proteica , Animales , Anticuerpos de Dominio Único/química , Anticuerpos de Dominio Único/metabolismo , Anticuerpos de Dominio Único/inmunología , Modelos MolecularesRESUMEN
OBJECTIVE: One of the difficulties in developing a novel drug for patients with amyotrophic lateral sclerosis (ALS) is the significant variation in the clinical course. To control this variation, a 12-week run-in period is used in some clinical trials. Based on the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALSFRS-R) change during the run-in period, only moderate progressors are selected in some clinical trials. Some reports showed that the ALSFRS-R progression rate was associated with survival. However, it is unclear whether the ALSFRS-R change in the run-in period is a useful prognostic factor of the ALSFRS-R change from baseline. In addition, we explore the inclusion criteria that could control the variability in ALS-function progression without setting a run-in period. METHODS: We utilized the Japanese and US ALS registry databases (JaCALS and PRO-ACT). Patients were classified into three populations (rapid, moderate, and slow progressors) based on the ALSFRS-R change prior to baseline. We also classified patients into three prognostic populations based on the ALSFRS-R change from baseline. We confirmed whether each of the three populations were matched with their respective three prognostic populations. RESULTS: Our data showed that the three groups classified by the ALSFRS-R change during the 12 weeks prior to baseline or by the rate of progression from onset to baseline did not accord with the three prognostic groups. CONCLUSIONS: Our results showed that the ALSFRS-R change in the run-in period or from onset to baseline is not useful for stratifying subsequent progression of functional decline in clinical trials.
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Esclerosis Amiotrófica Lateral , Humanos , Progresión de la Enfermedad , Pronóstico , Sistema de Registros , Bases de Datos FactualesRESUMEN
GPR34 is a recently identified G-protein coupled receptor, which has an immunomodulatory role and recognizes lysophosphatidylserine (LysoPS) as a putative ligand. Here, we report cryo-electron microscopy structures of human GPR34-Gi complex bound with one of two ligands bound: either the LysoPS analogue S3E-LysoPS, or M1, a derivative of S3E-LysoPS in which oleic acid is substituted with a metabolically stable aromatic fatty acid surrogate. The ligand-binding pocket is laterally open toward the membrane, allowing lateral entry of lipidic agonists into the cavity. The amine and carboxylate groups of the serine moiety are recognized by the charged residue cluster. The acyl chain of S3E-LysoPS is bent and fits into the L-shaped hydrophobic pocket in TM4-5 gap, and the aromatic fatty acid surrogate of M1 fits more appropriately. Molecular dynamics simulations further account for the LysoPS-regioselectivity of GPR34. Thus, using a series of structural and physiological experiments, we provide evidence that chemically unstable 2-acyl LysoPS is the physiological ligand for GPR34. Overall, we anticipate the present structures will pave the way for development of novel anticancer drugs that specifically target GPR34.
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Ácidos Grasos , Lisofosfolípidos , Humanos , Microscopía por Crioelectrón , Ácidos Grasos/metabolismo , Ligandos , Lisofosfolípidos/metabolismo , Receptores Lisofosfolípidos/agonistas , Receptores Lisofosfolípidos/metabolismoRESUMEN
Objective: To evaluate the effects of lurasidone on social functioning in schizophrenia over the course of a 6-week, double-blind, placebo-controlled study and a subsequent 12-week open-label extension study.Methods: A total of 478 patients with schizophrenia (per DSM-IV-TR criteria) randomized to either lurasidone 40 mg/d (n = 245) or placebo (n = 233) in the initial 6-week double-blind study (initiated May 2016, completed November 2018) were included in the analysis. Longer-term changes were examined in a sample of 146 patients who received lurasidone, and 141 who received placebo, during the 6-week study and received flexibly dosed (40-80 mg/d) lurasidone during the 12-week extension phase. The 4-item Positive and Negative Syndrome Scale (PANSS) prosocial subscale was used to examine changes in social functioning.Results: At week 6 of the double-blind phase, lurasidone-treated patients had significantly greater improvement on the PANSS prosocial subscale compared to placebo-treated patients (P < .01, effect size at week 6 = 0.33). Significant differences from placebo were also evident at week 2 (P < .05), week 4 (P < .001), and week 5 (P < .01). Across the 12-week extension phase, patients who received lurasidone during both the 6-week double-blind phase and the 12-week open-label phase continued to show successive decreases in scores on the 4-item PANSS prosocial subscale (score change of -3.0 from double-blind baseline to week 6; mean score change of -4.2 from double-blind baseline to week 12 of the extension phase).Conclusions: In patients with schizophrenia treated with lurasidone, social functioning improved relative to placebo during a 6-week double-blind study and continued to improve over the course of 12 weeks of extension treatment with lurasidone. Effects of lurasidone on social functioning appear to be comparable to what has been reported for other atypical antipsychotics.Trial Registration: EudraCT Numbers: 2016-000060-42 and 2016-000061-23.
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Antipsicóticos , Esquizofrenia , Humanos , Clorhidrato de Lurasidona/efectos adversos , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/inducido químicamente , Interacción Social , Antipsicóticos/efectos adversos , Tiempo , Método Doble Ciego , Resultado del TratamientoRESUMEN
ß-arrestins (ßarrs) are multifunctional proteins involved in signaling and regulation of seven transmembrane receptors (7TMRs), and their interaction is driven primarily by agonist-induced receptor activation and phosphorylation. Here, we present seven cryo-electron microscopy structures of ßarrs either in the basal state, activated by the muscarinic receptor subtype 2 (M2R) through its third intracellular loop, or activated by the ßarr-biased decoy D6 receptor (D6R). Combined with biochemical, cellular, and biophysical experiments, these structural snapshots allow the visualization of atypical engagement of ßarrs with 7TMRs and also reveal a structural transition in the carboxyl terminus of ßarr2 from a ß strand to an α helix upon activation by D6R. Our study provides previously unanticipated molecular insights into the structural and functional diversity encoded in 7TMR-ßarr complexes with direct implications for exploring novel therapeutic avenues.
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Dominios y Motivos de Interacción de Proteínas , Receptores Acoplados a Proteínas G , beta-Arrestinas , beta-Arrestinas/química , Microscopía por Crioelectrón , Receptores Acoplados a Proteínas G/química , Transducción de Señal , Conformación Proteica en Lámina beta , Conformación Proteica en Hélice alfa , HumanosRESUMEN
Cryo-EM single particle analysis has recently facilitated the high-resolution structural determination of numerous GPCR-G complexes. Diverse methodologies have been devised with this trend, and in the case of GPCR-Gi complexes, scFv16, an antibody that recognizes the intricate interface of the complex, has been mainly implemented to stabilize the complex. However, owing to their flexibility and heterogeneity, structural determinations of GPCR-Gi complexes remain both challenging and resource-intensive. By employing eGαt, which exhibits binding affinity to modified nanobody Nb35, the cryo-EM structure of Rhodopsin-eGαt complex was previously reported. Using this modified G protein, we determined the structure of the ETB-eGt complex bound to the modified Nb35. The determined structure of ETB receptor was the same as the previously reported ETB-Gi complex, and the resulting dataset demonstrated significantly improved anisotropy. This modified G protein will be utilized for the structural determination of other GPCR-Gi complexes.
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Proteínas de Unión al GTP , Rodopsina , Microscopía por Crioelectrón , Proteínas de Unión al GTP/metabolismo , Rodopsina/metabolismo , Anticuerpos/metabolismoRESUMEN
Surgery on spinal tumors becomes challenging when the tumor is ventral to the spinal cord. Conventionally, we approach it posteriorly through bilateral laminectomy and rotate the cord after sectioning the dentate ligament and nerve roots. However, manipulating the cord can be hazardous, and a long bilateral laminectomy can be invasive. Meanwhile, a narrow operative field and a limited lateral viewing angle in a unilateral approach constrained the surgeon. To overcome these problems, we previously reported a technique of modified unilateral approach where we incised the skin and the fascia horizontally and placed a pair of retractors longitudinally.The current article reports our experience applying this approach in 15 patients with ventrally located spinal tumors. The approach was performed on 10 schwannomas, 2 meningiomas, and 3 others. We evaluated paraspinal muscle atrophy on postoperative magnetic resonance imaging.The modified unilateral approach provided an excellent surgical field for removing ventrally located tumors. Gross total removal was achieved in 11 patients (92% of benign tumors). No neurological complications occurred except for one case of transient weakness. We encountered no wound-related late complications such as pain or deformity. The reduction of the cross-sectional area of the paraspinal muscles on the approach side (compared to the nonapproach side) was 0.93 (95% confidence interval: 0.72-1.06), indicating 7% atrophy (statistically nonsignificant, p = 0.48).We believe this simple technique can be useful for removing spinal tumors located ventral to the spinal cord.
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Neoplasias Meníngeas , Meningioma , Neoplasias de la Médula Espinal , Neoplasias de la Columna Vertebral , Humanos , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/cirugía , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Neoplasias de la Médula Espinal/diagnóstico por imagen , Neoplasias de la Médula Espinal/cirugía , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Laminectomía/métodos , Atrofia , Resultado del TratamientoRESUMEN
Endothelins and their receptors, type A (ETA) and type B (ETB), modulate vital cellular processes, including growth, survival, invasion and angiogenesis, through multiple G proteins. This review highlights the structural determinations of these receptors by X-ray crystallography and cryo-electron microscopy, and their activation mechanisms by endothelins. Explorations of the conformational changes upon receptor activation have provided insights into the unique G-protein coupling feature of the endothelin receptors. The review further delves into the binding modes of the clinical antagonist and the inverse agonists. These findings significantly contribute to understanding the mechanism of G-protein activation and have potential implications for drug development, particularly in the context of vasodilatory antagonists and agonists targeting the endothelin receptors.
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Agonismo Inverso de Drogas , Endotelinas , Microscopía por Crioelectrón , Endotelinas/metabolismo , Receptores de Endotelina/química , Receptores de Endotelina/metabolismo , Transducción de SeñalRESUMEN
BACKGROUND: The efficacy and safety of lurasidone monotherapy in patients with bipolar I depression with or without rapid cycling has not been previously investigated. METHODS: We performed subgroup analysis (rapid cycling/non-rapid cycling) of pooled data from two 6-week, randomized, double-blind, placebo-controlled trials of lurasidone monotherapy (20-60 mg/day or 80-120 mg/day). Analyses included mean change from baseline to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Safety assessments included the number of treatment-emergent adverse events (TEAEs) and laboratory assessments. RESULTS: Of 1024 patients randomized, 85 were rapid cycling. Mean change in MADRS total score in patients with non-rapid cycling and rapid cycling, respectively, was -14.8 (effect size = 0.47) and - 12.8 (effect size = 0.04) in the lurasidone 20-60 mg/day group, -14.3 (effect size = 0.41) and - 13.0 (effect size = 0.02) in the lurasidone 80-120 mg/day group and -10.6 and -13.3 in the placebo group. The most common TEAE in each subgroup was akathisia in both lurasidone groups. Treatment-emergent mania was reported only in a small number of rapid cycling and non-rapid cycling patients. LIMITATIONS: This was a post-hoc analysis of a short-term study that excluded patients with ≥8 cycles in the past year. CONCLUSIONS: In patients with non-rapid cycling bipolar depression, lurasidone monotherapy significantly improved depressive symptoms relative to placebo at both the 20-60 mg/day and 80-120 mg/day doses. In patients with rapid cycling, both doses of lurasidone displayed depressive symptom score reduction from baseline, but significant improvement was not observed likely due to high levels of improvement on placebo and small sample size.
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Antipsicóticos , Trastorno Bipolar , Humanos , Clorhidrato de Lurasidona/efectos adversos , Trastorno Bipolar/diagnóstico , Depresión , Quimioterapia Combinada , Manía/inducido químicamente , Manía/tratamiento farmacológico , Método Doble Ciego , Antipsicóticos/efectos adversos , Resultado del TratamientoRESUMEN
The endothelin ETB receptor is a promiscuous G-protein coupled receptor that is activated by vasoactive peptide endothelins. ETB signaling induces reactive astrocytes in the brain and vasorelaxation in vascular smooth muscle. Consequently, ETB agonists are expected to be drugs for neuroprotection and improved anti-tumor drug delivery. Here, we report the cryo-electron microscopy structure of the endothelin-1-ETB-Gi complex at 2.8 Å resolution, with complex assembly stabilized by a newly established method. Comparisons with the inactive ETB receptor structures revealed how endothelin-1 activates the ETB receptor. The NPxxY motif, essential for G-protein activation, is not conserved in ETB, resulting in a unique structural change upon G-protein activation. Compared with other GPCR-G-protein complexes, ETB binds Gi in the shallowest position, further expanding the diversity of G-protein binding modes. This structural information will facilitate the elucidation of G-protein activation and the rational design of ETB agonists.
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Endotelina-1 , Endotelinas , Endotelina-1/metabolismo , Microscopía por Crioelectrón , Receptor de Endotelina B/metabolismo , Endotelinas/metabolismo , Proteínas de Unión al GTP/metabolismoRESUMEN
The class 2 type V CRISPR effector Cas12 is thought to have evolved from the IS200/IS605 superfamily of transposon-associated TnpB proteins1. Recent studies have identified TnpB proteins as miniature RNA-guided DNA endonucleases2,3. TnpB associates with a single, long RNA (ωRNA) and cleaves double-stranded DNA targets complementary to the ωRNA guide. However, the RNA-guided DNA cleavage mechanism of TnpB and its evolutionary relationship with Cas12 enzymes remain unknown. Here we report the cryo-electron microscopy (cryo-EM) structure of Deinococcus radiodurans ISDra2 TnpB in complex with its cognate ωRNA and target DNA. In the structure, the ωRNA adopts an unexpected architecture and forms a pseudoknot, which is conserved among all guide RNAs of Cas12 enzymes. Furthermore, the structure, along with our functional analysis, reveals how the compact TnpB recognizes the ωRNA and cleaves target DNA complementary to the guide. A structural comparison of TnpB with Cas12 enzymes suggests that CRISPR-Cas12 effectors acquired an ability to recognize the protospacer-adjacent motif-distal end of the guide RNA-target DNA heteroduplex, by either asymmetric dimer formation or diverse REC2 insertions, enabling engagement in CRISPR-Cas adaptive immunity. Collectively, our findings provide mechanistic insights into TnpB function and advance our understanding of the evolution from transposon-encoded TnpB proteins to CRISPR-Cas12 effectors.
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Proteínas Bacterianas , Microscopía por Crioelectrón , Elementos Transponibles de ADN , Deinococcus , Endodesoxirribonucleasas , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/ultraestructura , Proteínas Asociadas a CRISPR/química , Proteínas Asociadas a CRISPR/metabolismo , Sistemas CRISPR-Cas , ADN/química , ADN/genética , ADN/metabolismo , ADN/ultraestructura , Elementos Transponibles de ADN/genética , ARN Guía de Sistemas CRISPR-Cas/química , ARN Guía de Sistemas CRISPR-Cas/genética , ARN Guía de Sistemas CRISPR-Cas/metabolismo , ARN Guía de Sistemas CRISPR-Cas/ultraestructura , Endodesoxirribonucleasas/química , Endodesoxirribonucleasas/metabolismo , Endodesoxirribonucleasas/ultraestructura , Deinococcus/enzimología , Deinococcus/genética , Especificidad por SustratoRESUMEN
Energy transfer from light-harvesting ketocarotenoids to the light-driven proton pump xanthorhodopsins has been previously demonstrated in two unique cases: an extreme halophilic bacterium1 and a terrestrial cyanobacterium2. Attempts to find carotenoids that bind and transfer energy to abundant rhodopsin proton pumps3 from marine photoheterotrophs have thus far failed4-6. Here we detected light energy transfer from the widespread hydroxylated carotenoids zeaxanthin and lutein to the retinal moiety of xanthorhodopsins and proteorhodopsins using functional metagenomics combined with chromophore extraction from the environment. The light-harvesting carotenoids transfer up to 42% of the harvested energy in the violet- or blue-light range to the green-light absorbing retinal chromophore. Our data suggest that these antennas may have a substantial effect on rhodopsin phototrophy in the world's lakes, seas and oceans. However, the functional implications of our findings are yet to be discovered.
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Organismos Acuáticos , Procesos Fototróficos , Bombas de Protones , Rodopsinas Microbianas , Organismos Acuáticos/metabolismo , Organismos Acuáticos/efectos de la radiación , Bacterias/metabolismo , Bacterias/efectos de la radiación , Carotenoides/metabolismo , Color , Cianobacterias/metabolismo , Cianobacterias/efectos de la radiación , Procesos Heterotróficos/efectos de la radiación , Luz , Océanos y Mares , Procesos Fototróficos/efectos de la radiación , Bombas de Protones/metabolismo , Bombas de Protones/efectos de la radiación , Rodopsinas Microbianas/metabolismo , Rodopsinas Microbianas/efectos de la radiación , Zeaxantinas/metabolismo , Zeaxantinas/efectos de la radiación , Luteína/metabolismo , Luteína/efectos de la radiación , Metagenoma , LagosRESUMEN
Human-robot interaction technology has contributed to improving sociality for humanoid robots. At scales far from human scales, a microrobot can interact with an environment in a small world. Microsensors have been applied to measurement of forces by flying or walking insects. Meanwhile, most previous works focused on the measurement of the behavior of insects. Here, we propose microrobot-insect interactions by soft microfingers integrated with artificial muscle actuators and tactile sensors, which has been developed for a haptic teleoperation robot system. A soft pneumatic balloon actuator acts as the artificial muscle, and a flexible strain sensor using a liquid metal provides tactile sensing. Force interaction between a pill bug and the microfinger could be accomplished. The microfinger (12 mm × 3 mm × 490 µm) can move and touch an insect, and it can detect reaction force from an insect. The measured reaction force from the legs of a pill bug as a representative insect was less than 10 mN. This paper presents a microfinger as an end effector for the active sensing of reaction force from a small insect. We anticipate that our results will lead to further evaluation of small living things as well as technology development for human-environment interaction.
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Robótica , Percepción del Tacto , Animales , Humanos , Insectos , Fenómenos Mecánicos , TactoRESUMEN
Lysophosphatidic acid receptor 1 (LPA1) is one of the six G protein-coupled receptors activated by the bioactive lipid, lysophosphatidic acid (LPA). LPA1 is a drug target for various diseases, including cancer, inflammation, and neuropathic pain. Notably, LPA1 agonists have potential therapeutic value for obesity and urinary incontinence. Here, we report a cryo-electron microscopy structure of the active human LPA1-Gi complex bound to ONO-0740556, an LPA analog with more potent activity against LPA1. Our structure elucidated the details of the agonist binding mode and receptor activation mechanism mediated by rearrangements of transmembrane segment 7 and the central hydrophobic core. A structural comparison of LPA1 and other phylogenetically-related lipid-sensing GPCRs identified the structural determinants for lipid preference of LPA1. Moreover, we characterized the structural polymorphisms at the receptor-G-protein interface, which potentially reflect the G-protein dissociation process. Our study provides insights into the detailed mechanism of LPA1 binding to agonists and paves the way toward the design of drug-like agonists targeting LPA1.
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Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Neuralgia , Receptores del Ácido Lisofosfatídico , Microscopía por Crioelectrón , Humanos , Receptores del Ácido Lisofosfatídico/metabolismoRESUMEN
Aegagropila linnaei is a freshwater green alga, which at one time was distributed widely in the northern hemisphere. The aggregate often forms beautiful spherical shapes known as "lake balls" or "Marimo". The population of Marimo has been rapidly decreasing worldwide, and today the large Marimo, with a diameter of more than 12 cm, exit only in Lake Akan in Japan. However, how Marimo grow and maintain their unique spherical shape in natural habitats remains unsolved. Here we show that Marimo are "polished" into spheres by the rotation induced by wind waves. Such a process enhances the water exchange between the interior and exterior of the Marimo, thereby recycling nutrients for growth. Our results provide an intriguing model of a physical environment interacting with biological processes in a self-sustaining ecosystem. We also demonstrate that Marimo have a spherical annual ring structure, and their growth rate is associated with ice cover. The balance between the ecology of Marimo and the water environment in Lake Akan is highly vulnerable and at risk of irreversible degradation. We must endeavor to rescue Marimo from the fate of a "canary in the coal mine" of global climate change.
RESUMEN
OBJECTIVE: Laser interstitial thermotherapy has widely available. The current treatment, however, often relies on the experience of the treatment provider. To improve the accuracy of the laser treatment system in the future, it is necessary to construct simulation systems with physical properties such as heat conduction as a reference. However, no studies to measure a thermophysical property, of brain tumors have yet been conducted. Therefore, the present study was performed to measure specific heat capacities. MATERIALS AND METHODS: The specific heat capacities of tissues obtained from two willed bodies and eight specimens of brain tumors were measured by differential scanning calorimetry. RESULT: In normal brain tissues, changes of specific heat capacity were minimal as the tissue was heated from 37°C to 61°C. Conversely, in brain tumor tissues, changes of specific heat capacity between 37°C and 43°C were substantial, and the difference in the rate of change of specific heat capacity between brain tumor tissues and normal brain tissues was significant. CONCLUSIONS: The specific heat measurements of brain tissues and brain tumor tissues showed that changes of specific heat capacity between 37°C and 43°C were greater in brain tumor than in normal brain tissues.
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Neoplasias Encefálicas/terapia , Encéfalo/fisiología , Simulación por Computador , Hipertermia Inducida/métodos , Rayos Láser , Modelos Biológicos , Neoplasias Encefálicas/fisiopatología , Rastreo Diferencial de Calorimetría , Calor , Humanos , Hipertermia Inducida/instrumentaciónRESUMEN
OBJECTIVE: To evaluate the association between strengths use and self-esteem among visually impaired individuals in Study 1 and reveal the causal effect of a strengths intervention in Study 2. DESIGN: A prospective cross-sectional design in Study 1 and a randomized controlled, open-label, parallel-group comparative design in Study 2. SETTING: Several welfare institutions for visually impaired individuals in the Kanto area of Japan. SUBJECTS: In Study 1, 59 participants with visual impairments (mean age = 49.34 ± 4.89 years, range = 22-82 years) were recruited. In Study 2, participants (mean age = 41.36 ± 12.09 years, range = 22-61 years) were recruited and randomly assigned to an intervention (n = 11) or wait-list control group (n = 11). INTERVENTION: A strengths intervention was performed in Study 2. MAIN MEASURES: In Study 1, we examined the association between Strengths Use Scale and Rosenberg Self-Esteem Scale scores. In Study 2, the primary outcome was the difference in change in Rosenberg Self-Esteem Scale scores from baseline to one-month follow-up between the groups. RESULTS: In Study 1, simple and multiple regression analyses revealed that the Rosenberg Self-Esteem Scale score was significantly associated with the Strengths Use Scale score (ß = 0.60, P < 0.001; ß = 0.55, P < 0.001, respectively). In Study 2, we found a significant between-groups difference in the improvement in Rosenberg Self-Esteem Scale scores from baseline to one-month follow-up (F(1, 19) = 18.61, P < 0.001). CONCLUSION: Utilizing psychological strengths might improve self-esteem among visually impaired individuals.