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1.
Sensors (Basel) ; 21(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202277

RESUMO

This study proposed a plan for implementing a pleasant and healthy indoor landscape in subway station space. To this end, it established a 3D landscape model of the subway interior by reviewing previous studies on indoor landscape and the greenness index of indoor spaces. Moreover, it investigated and analyzed psychophysiological responses of users to environmental indoor landscape design in subway station space. Subway stations were classified as underground subway stations and ground subway stations according to the presence of natural light inflow. The greenness index of indoor spaces was also divided into four types of 0%, 10%, 15%, and 20%. Through this process, eight 3D landscape models of the subway interior were implemented. In addition, this study investigated psychophysiological responses of 60 male and female adults in their 20 s and 30 s using the models implemented. The investigation result was analyzed based on a frequency analysis, the χ2 test, T-test, one-way analysis of variance, and multidimensional scaling, which were performed in SPSS Statistics 25. The results of this study can be summarized as follows. First, physiological responses of research subjects were analyzed based on their prefrontal α wave asymmetric values. The analytic result showed that the environment where interior landscape was adopted produced more positive effects than the environment where interior landscape was not adopted. Second, psychological responses of research subjects were examined based on their greenness index preference, awareness of interior landscape area, attention restoration effect, and space images. The analytic result indicated that, among eight 3D landscape models of the subway interior, they preferred the model with the greenness index of 15% for underground subway stations. In addition, they preferred the model with the greenness index of 10% the most for ground subway stations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Ferrovias , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Feminino , Humanos , Masculino , Psicofisiologia
2.
J Org Chem ; 85(3): 1376-1384, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31773962

RESUMO

Chemoselective ligation of two 28-mer peptides has been accomplished using the Suzuki-Miyaura cross-coupling reaction at or near physiological temperature in an aqueous solution containing sodium dodecyl sulfate in 83% yield. The effects of Pd source, solvent, base, and temperature were investigated, and the optimized reaction conditions were studied for compatibility with naturally present and artificially introduced functional groups in peptides including S-protected thiol and azide. The peptide conjugations were carried out in high yield (90%) with their functional groups intact. This method also allowed for facile introduction of an affinity tag or fluorescent probe into 20-mer peptides in >80% yield. These results suggest that the Suzuki-Miyaura cross-coupling is useful for multiple conjugations of peptides in conjunction with conventional conjugation reactions performed in sequence.

3.
Breast Cancer Res ; 21(1): 150, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31878959

RESUMO

BACKGROUND: CDK4/6 inhibitors in combination with endocrine therapy (AE/AI/SERDs) are approved for the treatment of ER+ advanced breast cancer (BCa). However, not all patients benefit from CDK4/6 inhibitors therapy. We previously reported a novel therapeutic agent, ERX-11, that binds to the estrogen receptor (ER) and modulates ER-coregulator interactions. Here, we tested if the combination of ERX-11 with agents approved for ER+ BCa would be more potent. METHODS: We tested the effect of combination therapy using BCa cell line models, including those that have acquired resistance to tamoxifen, letrozole, or CDK4/6 inhibitors or have been engineered to express mutant forms of the ER. In vitro activity was tested using Cell Titer-Glo, MTT, and apoptosis assays. Mechanistic studies were conducted using western blot, reporter gene assays, RT-qPCR, and mass spectrometry approaches. Xenograft, patient-derived explants (PDEs), and xenograft-derived explants (XDE) were used for preclinical evaluation and toxicity. RESULTS: ERX-11 inhibited the proliferation of therapy-resistant BCa cells in a dose-dependent manner, including ribociclib resistance. The combination of ERX-11 and CDK4/6 inhibitor was synergistic in decreasing the proliferation of both endocrine therapy-sensitive and endocrine therapy-resistant BCa cells, in vitro, in xenograft models in vivo, xenograft-derived explants ex vivo, and in primary patient-derived explants ex vivo. Importantly, the combination caused xenograft tumor regression in vivo. Unbiased global mass spectrometry studies demonstrated profound decreases in proliferation markers with combination therapy and indicated global proteomic changes in E2F1, ER, and ER coregulators. Mechanistically, the combination of ERX-11 and CDK4/6 inhibitor decreased the interaction between ER and its coregulators, as evidenced by immunoprecipitation followed by mass spectrometry studies. Biochemical studies confirmed that the combination therapy significantly altered the expression of proteins involved in E2F1 and ER signaling, and this is primarily driven by a transcriptional shift, as noted in gene expression studies. CONCLUSIONS: Our results suggest that ERX-11 inhibited the proliferation of BCa cells resistant to both endocrine therapy and CDK4/6 inhibitors in a dose-dependent manner and that the combination of ERX-11 with a CDK4/6 inhibitor may represent a viable therapeutic approach.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Moduladores de Receptor Estrogênico/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptores de Estrogênio/metabolismo , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Feminino , Humanos , Imuno-Histoquímica , Camundongos
4.
Molecules ; 24(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370197

RESUMO

The interaction between androgen receptor (AR) and coactivator proteins plays a critical role in AR-mediated prostate cancer (PCa) cell growth, thus its inhibition is emerging as a promising strategy for PCa treatment. To develop potent inhibitors of the AR-coactivator interaction, we have designed and synthesized a series of bis-benzamides by modifying functional groups at the N/C-terminus and side chains. A structure-activity relationship study showed that the nitro group at the N-terminus of the bis-benzamide is essential for its biological activity while the C-terminus can have either a methyl ester or a primary carboxamide. Surveying the side chains with various alkyl groups led to the identification of a potent compound 14d that exhibited antiproliferative activity (IC50 value of 16 nM) on PCa cells. In addition, biochemical studies showed that 14d exerts its anticancer activity by inhibiting the AR-PELP1 interaction and AR transactivation.


Assuntos
Benzamidas/farmacologia , Proteínas Correpressoras/química , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/química , Fatores de Transcrição/química , Antagonistas de Androgênios/química , Antagonistas de Androgênios/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas Correpressoras/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Antígeno Prostático Específico/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Conformação Proteica em alfa-Hélice/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Receptores Androgênicos/efeitos dos fármacos , Relação Estrutura-Atividade , Fatores de Transcrição/genética , Ativação Transcricional/efeitos dos fármacos
5.
J Sci Food Agric ; 97(9): 2891-2897, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27790703

RESUMO

BACKGROUND: The potential of fermented buckwheat as a feed additive was studied to increase l-carnitine and γ-aminobutyric acid (GABA) in designer eggs. Buckwheat contains high levels of lysine, methionine and glutamate, which are precursors for the synthesis of l-carnitine and GABA. Rhizopus oligosporus was used for the fermentation of buckwheat to produce l-carnitine and GABA that exert positive effects such as enhanced metabolism, antioxidant activities, immunity and blood pressure control. RESULTS: A novel analytical method for simultaneously detecting l-carnitine and GABA was developed using liquid chromatography/mass spectrometry (LC/MS) and LC/MS/MS. The fermented buckwheat extract contained 4 and 34 times more l-carnitine and GABA respectively compared with normal buckwheat. Compared with the control, the fermented buckwheat extract-fed group showed enriched l-carnitine (13.6%) and GABA (8.4%) in the yolk, though only l-carnitine was significantly different (P < 0.05). Egg production (9.4%), albumen weight (2.1%) and shell weight (5.8%) were significantly increased (P < 0.05). There was no significant difference in yolk weight, and total cholesterol (1.9%) and triglyceride (4.9%) in the yolk were lowered (P < 0.05). CONCLUSION: Fermented buckwheat as a feed additive has the potential to produce l-carnitine- and GABA-enriched designer eggs with enhanced nutrition and homeostasis. These designer eggs pose significant potential to be utilized in superfood production and supplement industries. © 2016 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Carnitina/metabolismo , Galinhas/metabolismo , Ovos/análise , Fagopyrum/química , Fagopyrum/microbiologia , Aditivos Alimentares/química , Rhizopus/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Carnitina/análise , Fagopyrum/metabolismo , Feminino , Fermentação , Aditivos Alimentares/metabolismo , Espectrometria de Massas em Tandem , Ácido gama-Aminobutírico/análise
6.
Biol Reprod ; 94(1): 11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26607719

RESUMO

Testosterone acts though the androgen receptor in Sertoli cells to support germ cell development (spermatogenesis) and male fertility, but the molecular and cellular mechanisms by which testosterone acts are not well understood. Previously, we found that in addition to acting through androgen receptor to directly regulate gene expression (classical testosterone signaling pathway), testosterone acts through a nonclassical pathway via the androgen receptor to rapidly activate kinases that are known to regulate spermatogenesis. In this study, we provide the first evidence that nonclassical testosterone signaling occurs in vivo as the MAP kinase cascade is rapidly activated in Sertoli cells within the testis by increasing testosterone levels in the rat. We find that either classical or nonclassical signaling regulates testosterone-mediated Rhox5 gene expression in Sertoli cells within testis explants. The selective activation of classical or nonclassical signaling pathways in Sertoli cells within testis explants also resulted in the differential activation of the Zbtb16 and c-Kit genes in adjacent spermatogonia germ cells. Delivery of an inhibitor of either pathway to Sertoli cells of mouse testes disrupted the blood-testis barrier that is essential for spermatogenesis. Furthermore, an inhibitor of nonclassical testosterone signaling blocked meiosis in pubertal mice and caused the loss of meiotic and postmeiotic germ cells in adult mouse testes. An inhibitor of the classical pathway caused the premature release of immature germ cells. Collectively, these observations indicate that classical and nonclassical testosterone signaling regulate overlapping and distinct functions that are required for the maintenance of spermatogenesis and male fertility.


Assuntos
Transdução de Sinais/fisiologia , Espermatogênese/fisiologia , Testosterona/fisiologia , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Fertilidade/efeitos dos fármacos , Fertilidade/fisiologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica , Proteínas Proto-Oncogênicas c-kit/biossíntese , Proteínas Proto-Oncogênicas c-kit/genética , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Células de Sertoli/metabolismo , Transdução de Sinais/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Testículo/citologia , Testículo/efeitos dos fármacos , Testículo/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
J Phys Ther Sci ; 28(3): 1071-3, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27134414

RESUMO

[Purpose] The present study investigated the effects of squat exercises with and without a variety of tools including a gym ball, wedge, and elastic band on the vastus lateralis and vastus medialis oblique muscles. [Subjects and Methods] A total of twenty healthy subjects with no history of neurological, musculoskeletal injury, or pain in the lower extremities were recruited. All subjects performed four types of exercise (conventional squat exercise, squat exercise with a gym ball, squat exercise with a wedge, squat exercise with an elastic band). [Results] There were no significant differences between exercises in comparison of the vastus lateralis muscle activity. In the squat exercise with a wedge, significantly higher activity of the vastus medialis oblique muscle was found compared with in the squat exercise with an elastic band. [Conclusion] The present study suggests that the conventional squat exercise can be one of the useful interventions for patients with patellofemoral pain syndrome.

8.
Biomed Eng Lett ; 14(2): 267-278, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38374899

RESUMO

This research was conducted to apply polyimide tape, which has the advantages of low price ans strong adhesive strength, to the neural electrode process. In addition, to maximize the low-cost characteristics, a fabrication process based on UV laser patterning rather than a photolithography process was introduced. The fabrication process started by attaching the gold sheet on the conductive double-sided tape without being torn or crushed. Then, the gold sheet and the double-sided tape were patterned together using UV laser. The patterned layer was transferred to the single-side polyimide tape. For insulation layer, electrode site opened single-sided polyimide tape was prepared. Polydimethylsiloxane was used as an adhesion layer, and alignment between electrode sites and opening sites was processed manually. The minimum line width achieved through the proposed fabrication process was approximately 100 µm, and the sheet resistance of the conductive layer was 0.635 Ω/sq. Measured cathodal charge storage capacity was 0.72 mC/cm2 and impedance at 1 kHz was 4.07 kΩ/cm2. Validation of fabricated electrode was confirmed by conducting 30 days accelerated soak test, flexibility test, adhesion test and ex vivo stimulation test. The novel flexible neural electrodes based on single-sided polyimide tape and UV laser patterned gold sheet was fabricated successfully. Conventional neural electrode fabrication processes based on polyimide substrate has a disadvantages such as long fabrication time, expensive costs, and probability of delamination between layers. However, the novel fabrication process which we introduced can overcome many shortcomings of existing processes, and offers great advantages such as simplicity of fabrication, inexpensiveness, flexibility and long-term reliability.

9.
ACS Pharmacol Transl Sci ; 7(7): 2023-2043, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39022350

RESUMO

Estrogen receptor coregulator binding modulators (ERXs) are a novel class of molecules targeting the interaction between estrogen receptor α (ERα) and its coregulator proteins, which has proven to be an attractive strategy for overcoming endocrine resistance in breast cancer. We previously reported ERX-11, an orally bioavailable tris-benzamide, that demonstrated promising antitumor activity against ERα-positive breast cancer cells. To comprehend the significance of the substituents in ERX-11, we carried out structure-activity relationship studies. In addition, we introduced additional alkyl substituents at either the N- or C-terminus to improve binding affinity and biological activity. Further optimization guided by conformational restriction led to the identification of a trans-4-phenylcyclcohexyl group at the C-terminus (18h), resulting in a greater than 10-fold increase in binding affinity and cell growth inhibition potency compared to ERX-11. Tris-benzamide 18h disrupted the ERα-coregulator interaction and inhibited the ERα-mediated transcriptional activity. It demonstrated strong antiproliferative activity on ERα-positive breast cancer cells both in vitro and in vivo, offering a promising potential as a therapeutic candidate for treating ERα-positive breast cancer.

10.
Cancers (Basel) ; 16(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38339252

RESUMO

Ovarian cancer (OCa) is the most lethal form of gynecologic cancer, and the tumor heterogeneities at the molecular, cellular, and tissue levels fuel tumor resistance to standard therapies and pose a substantial clinical challenge. Here, we tested the hypothesis that the heightened basal endoplasmic reticulum stress (ERS) observed in OCa represents an exploitable vulnerability and may overcome tumor heterogeneity. Our recent studies identified LIPA as a novel target to induce ERS in cancer cells using the small molecule ERX-41. However, the role of LIPA and theutility of ERX-41 to treat OCa remain unknown. Expression analysis using the TNMplot web tool, TCGA data sets, and immunohistochemistry analysis using a tumor tissue array showed that LIPA is highly expressed in OCa tissues, compared to normal tissues. ERX-41 treatment significantly reduced the cell viability and colony formation ability and promoted the apoptosis of OCa cells. Mechanistic studies revealed a robust and consistent induction of ERS markers, including CHOP, elF2α, PERK, and ATF4, upon ERX-41 treatment. In xenograft and PDX studies, ERX-41 treatment resulted in a significant reduction in tumor growth. Collectively, our results suggest that ERX-41 is a novel therapeutic agent that targets the LIPA with a unique mechanism of ERS induction, which could be exploited to treat heterogeneity in OCa.

11.
Arch Orthop Trauma Surg ; 133(7): 1029-32, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23604791

RESUMO

Closed flexor tendon ruptures due to trauma without external wound are rare. When the flexor tendon has excessive loading, failure occurs at the tendon insertion or its origin from the bone. It is likely to result in avulsion fracture rather than rupture of the proper portion of the tendon by forceful grasping with hyperextension. However, we have experienced three cases of closed flexor tendon ruptures at zone V, caused by forceful grasping or hyperextension mechanism against resistance. On physical examination, these patients could not flex interphalangeal joint of thumb or distal interphalangeal joint of the fifth finger. All patients underwent MRI or ultrasonography to find out the location of loss in continuity of the flexor tendons before the operation. After identifying the location, flexor tendon repair or tendon graft using palmaris longus were performed.


Assuntos
Traumatismos dos Tendões/etiologia , Traumatismos dos Tendões/cirurgia , Articulação do Punho/cirurgia , Idoso , Diagnóstico por Imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ruptura , Traumatismos dos Tendões/diagnóstico , Ultrassonografia , Articulação do Punho/diagnóstico por imagem
12.
Artigo em Inglês | MEDLINE | ID: mdl-38083392

RESUMO

In this work, a fabrication process for implantable electrodes using a Cyclic Olefin Copolymer (COC) substrate and a SU-8 passivation layer was presented. COC and SU-8 were shown to be suitable for implantable neural electrodes due to their biocompatibility, chemical resistance, and thermal stability. The electrodes were successfully patterned on the COC film, and the SU-8 passivation layer was coated while maintaining site-opened via photolithography. The photocrosslinking lamination of the substrate and passivation layer was used to produce electrodes with fine line widths of 20um without applying heat.


Assuntos
Cicloparafinas , Microeletrodos , Eletrodos Implantados
13.
Artigo em Inglês | MEDLINE | ID: mdl-38083447

RESUMO

A retinal prosthesis is a device that can provide artificial vision to people who have lost their sight from certain retinal disorder. Because the device needs to be inserted into the body, high flexibility and reliability is required. Recently, devices using thermoplastic polymers such as LCP and COC as substrates have been studied. Being a highly functional integrated device, retinal prosthesis poses many design challenges. Among them, the stimulation chip embedding can be a particularly important task. Although it is common to use a wire bonding method for chip embedding, there are several limitations that are difficult to apply to implantable device. In this investigation, a novel approach is developed for high spaceefficient electrical connections and perform reliable encapsulation of integrated circuits to replace wire bonding. Since designing and manufacturing the stimulator chip used in retinal prosthesis requires non-negligible cost, a silicon die with the identical shape was selected as a substitute for testing purposes.


Assuntos
Cicloparafinas , Doenças Retinianas , Próteses Visuais , Humanos , Reprodutibilidade dos Testes , Polímeros
14.
Cancers (Basel) ; 15(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37568799

RESUMO

BACKGROUND: Red blood cell distribution width (RDW) is a standard parameter of complete blood count and indicates the variability in red blood cell size. This study aimed to determine whether preoperative RDW can be used to predict the recurrence and prognosis of endometrial carcinoma. METHODS: The medical records of 431 patients diagnosed with endometrial carcinoma were retrospectively reviewed between May 2006 and June 2018. In addition to RDW, the clinicopathological factors, survival curves, and prognoses of the patients with endometrial carcinoma were compared between the high (n = 213) and low (n = 218) groups according to the median RDW value (12.8%). RESULTS: The patients with high RDW had significantly advanced-stage (p = 0.00) pelvic lymph node metastasis (p = 0.01) and recurrence (p = 0.01) compared to those in the low-RDW group. In univariate analysis with DFS as the endpoint, surgical stage, type II histology, grade, RDW, and lymph node metastasis were independently associated with survival. Patients with high RDW values had significantly shorter disease-free survival and overall survival than those with low RDW values (log-rank p = 0.03, log-rank p = 0.04, respectively). CONCLUSION: Our results demonstrate that RDW is a simple and convenient indicator of endometrial carcinoma recurrence. Prospective studies are needed to validate the findings of the current study.

15.
J Org Chem ; 77(20): 9156-62, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23009711

RESUMO

A simple, mild, and inexpensive biphasic functionalization approach is attempted for preparing an ideal core-shell-type resin. The core-shell-type architecture was constructed by coupling Fmoc-OSu to the amino groups on the shell layer of an aminomethyl polystyrene (AM PS) resin. The shell layer thickness of the resin could be easily controlled under mild conditions, which was characterized by confocal laser scanning microscopy (CLSM). The efficiency of core-shell-type resin for solid-phase peptide synthesis (SPPS) was demonstrated by the synthesis of various peptides and compared with commercially available noncore-shell-type resins such as AM PS and poly(ethylene glycol)-based resins. The core-shell-type resin provided effective performance during the synthesis of hydrophobic peptide sequences, a disulfide-bridged cyclic peptide, and a difficult PNA sequence. Furthermore, a highly aggregative peptide fragment, MoPrP 105-125, was synthesized more efficiently on the core-shell-type resin under microwave conditions than AM PS and ChemMatrix resins.


Assuntos
Peptídeos/síntese química , Poliestirenos/química , Resinas Sintéticas/química , Microscopia Confocal , Peptídeos/química , Polietilenoglicóis/química
16.
J Exerc Rehabil ; 18(5): 294-298, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36420473

RESUMO

The purpose of this study is to identify the factors affecting the job stress of commercial sports center workers on organizational commitment and turnover intention. The causal relationship between their demographic characteristics and job stress was investigated for 261 out of 300 workers working at commercial sports centers in Seoul, Incheon, and Gyeonggi province. There was a difference by work type, and it was found that there was a difference between regular and contract workers. Role-related and interpersonal relationships had a negative influence relationship in terms of tenure commitment, normative commitment, and affective commitment. Job characteristics, role-related, interpersonal relationship, and compensation system had an influence on turnover intention. In other words, it was found that role-related and interpersonal relationships had a positive effect on turnover intention, and job characteristics and compensation system had a negative effect on turnover intention. It was found that job stress affects both organizational commitment and turnover intention. The results of this study indicate that job stress, organizational commitment, and turnover intention should be dealt with mainly in order to reduce turnover intention of commercial sports center workers. In other words, clearer guidelines on the role of commercial sports center workers and various welfare programs for improving human relationships should be provided. Therefore, commercial sports centers should continuously research and develop ways to maximize job satisfaction from the perspective of workers in order to reduce job stress and induce positive organizational commitment.

17.
Heliyon ; 8(10): e10991, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36276728

RESUMO

A processing map is required for Ti alloys to find processing parameters securing a high formability. This study adopted the extreme gradient boosting (XGB) approach of machine learning to predict a flow curve and plot a processing map with less experiments for the first time. The optimum XGB model predicted flow curves of Ti-6Al-2Sn-2Zr-2Mo-2Cr-0.15Si at 1073-1273 K and 10 s-1. The predicted data were used to plot a processing map, which showed a higher accuracy in the instability map as compared with the map without XGB. The XGB model also anticipated the power dissipation map at low strain rates. The low accuracy at high strain rates would be improved by alleviating the bias towards a flow hardening. This work has successfully proven the potential usefulness of XGB for plotting an enhanced processing map in light of a higher accuracy with less experiments.

18.
Nat Cancer ; 3(7): 866-884, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35654861

RESUMO

Triple-negative breast cancer (TNBC) has a poor clinical outcome, due to a lack of actionable therapeutic targets. Herein we define lysosomal acid lipase A (LIPA) as a viable molecular target in TNBC and identify a stereospecific small molecule (ERX-41) that binds LIPA. ERX-41 induces endoplasmic reticulum (ER) stress resulting in cell death, and this effect is on target as evidenced by specific LIPA mutations providing resistance. Importantly, we demonstrate that ERX-41 activity is independent of LIPA lipase function but dependent on its ER localization. Mechanistically, ERX-41 binding of LIPA decreases expression of multiple ER-resident proteins involved in protein folding. This targeted vulnerability has a large therapeutic window, with no adverse effects either on normal mammary epithelial cells or in mice. Our study implicates a targeted strategy for solid tumors, including breast, brain, pancreatic and ovarian, whereby small, orally bioavailable molecules targeting LIPA block protein folding, induce ER stress and result in tumor cell death.


Assuntos
Estresse do Retículo Endoplasmático , Neoplasias de Mama Triplo Negativas , Animais , Humanos , Lipase/química , Camundongos , Dobramento de Proteína , Neoplasias de Mama Triplo Negativas/genética
19.
Nat Commun ; 12(1): 5116, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433814

RESUMO

NMDA receptor (NMDAR) and GABA neuronal dysfunctions are observed in animal models of autism spectrum disorders, but how these dysfunctions impair social cognition and behavior remains unclear. We report here that NMDARs in cortical parvalbumin (Pv)-positive interneurons cooperate with gap junctions to promote high-frequency (>80 Hz) Pv neuronal burst firing and social cognition. Shank2-/- mice, displaying improved sociability upon NMDAR activation, show impaired cortical social representation and inhibitory neuronal burst firing. Cortical Shank2-/- Pv neurons show decreased NMDAR activity, which suppresses the cooperation between NMDARs and gap junctions (GJs) for normal burst firing. Shank2-/- Pv neurons show compensatory increases in GJ activity that are not sufficient for social rescue. However, optogenetic boosting of Pv neuronal bursts, requiring GJs, rescues cortical social cognition in Shank2-/- mice, similar to the NMDAR-dependent social rescue. Therefore, NMDARs and gap junctions cooperate to promote cortical Pv neuronal bursts and social cognition.


Assuntos
Junções Comunicantes/metabolismo , Interneurônios/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Cognição Social , Sinapses/fisiologia , Animais , Junções Comunicantes/genética , Masculino , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Parvalbuminas/genética , Parvalbuminas/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Comportamento Social , Sinapses/genética
20.
Micromachines (Basel) ; 11(8)2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32823978

RESUMO

Microabrasive-based lapping is widely used in the manufacturing of single-crystal substrates such as sapphire, SiC, and GaN. Although many studies have been conducted to improve the lapping process characteristics, most of them focused on process conditions or consumables. In this study, the effect of the lapping platen groove density on the lapping characteristics was studied using a sapphire substrate. Groove density was defined as the ratio of groove width to groove pitch, and the displacement of the lapping head was measured to calculate the oil film thickness. It was confirmed that, for groove densities below 0.30, hydroplaning occurs when the oil film thickness increases. When the oil film thickness is larger than the abrasive particle size, the material removal rate is low because the abrasive does not participate in the lapping process. When the oil film was developed, the experimental results showed a high surface roughness and poor flatness of the substrate, as only large abrasive particles participated in the lapping process. Therefore, to improve the lapping characteristics, it is important to reduce the groove density by reducing the groove pitch, which prevents the development of the oil film.

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