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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(5): 512-517, 2024 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-38802913

RESUMO

Glyceryl phenylbutyrate (GPB) serves as a long-term management medication for Ornithine transcarbamylase deficiency (OTCD), effectively controlling hyperammonemia, but there is a lack of experience in using this medicine in China. This article retrospectively analyzes the case of a child diagnosed with OTCD at Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, including a review of related literature. After diagnosis, the patient was treated with GPB, followed by efficacy follow-up and pharmacological monitoring. The 6-year and 6-month-old male patient exhibited poor speech development, disobedience, temper tantrums, and aggressive behavior. Blood ammonia levels peaked at 327 µmol/L; urine organic acid analysis indicated elevated uracil levels; cranial MRI showed extensive abnormal signals in both cerebral hemispheres. Genetic testing revealed de novo mutation in the OTC gene (c.241T>C, p.S81P). Blood ammonia levels were approximately 43, 80, and 56 µmol/L at 1, 2, and 3 months after starting GPB treatment, respectively. During treatment, blood ammonia was well-controlled without drug-related adverse effects. The patient showed improvement in developmental delays, obedience, temperament, and absence of aggressive behavior.


Assuntos
Doença da Deficiência de Ornitina Carbomoiltransferase , Fenilbutiratos , Humanos , Masculino , Doença da Deficiência de Ornitina Carbomoiltransferase/tratamento farmacológico , Doença da Deficiência de Ornitina Carbomoiltransferase/genética , Fenilbutiratos/uso terapêutico , Criança , Glicerol/análogos & derivados
2.
Sci Rep ; 14(1): 10952, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740850

RESUMO

It is recognized as a promising therapeutic strategy for cocaine use disorder to develop an efficient enzyme which can rapidly convert cocaine to physiologically inactive metabolites. We have designed and discovered a series of highly efficient cocaine hydrolases, including CocH5-Fc(M6) which is the currently known as the most efficient cocaine hydrolase with both the highest catalytic activity against (-)-cocaine and the longest biological half-life in rats. In the present study, we characterized the time courses of protein appearance, pH, structural integrity, and catalytic activity against cocaine in vitro and in vivo of a CocH5-Fc(M6) bulk drug substance produced in a bioreactor for its in vitro and in vivo stability after long-time storage under various temperatures (- 80, - 20, 4, 25, or 37 °C). Specifically, all the tested properties of the CocH5-Fc(M6) protein did not significantly change after the protein was stored at any of four temperatures including - 80, - 20, 4, and 25 °C for ~ 18 months. In comparison, at 37 °C, the protein was less stable, with a half-life of ~ 82 days for cocaine hydrolysis activity. Additionally, the in vivo studies further confirmed the linear elimination PK profile of CocH5-Fc(M6) with an elimination half-life of ~ 9 days. All the in vitro and in vivo data on the efficacy and stability of CocH5-Fc(M6) have consistently demonstrated that CocH5-Fc(M6) has the desired in vitro and in vivo stability as a promising therapeutic candidate for treatment of cocaine use disorder.


Assuntos
Cocaína , Estabilidade Enzimática , Animais , Cocaína/metabolismo , Ratos , Hidrólise , Concentração de Íons de Hidrogênio , Masculino , Meia-Vida , Temperatura , Amidoidrolases/metabolismo , Hidrolases de Éster Carboxílico , Proteínas Recombinantes
3.
Domest Anim Endocrinol ; 88: 106848, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38574690

RESUMO

Insulin is a potent adipogenic hormone that triggers a series of transcription factors that regulate the differentiation of preadipocytes into mature adipocytes. Ciglitazone specifically binds to peroxisome proliferator-activated receptor-γ (PPARγ), thereby promoting adipocyte differentiation. As a natural ligand of PPARγ, oleic acid (OA) can promote the translocation of PPARγ into the nucleus, regulate the expression of downstream genes, and promote adipocyte differentiation. We hypothesized that ciglitazone and oleic acid interact with insulin to enhance bovine preadipocyte differentiation. Preadipocytes were cultured 96 h in differentiation medium containing 10 mg/L insulin (I), 10 mg/L insulin + 10 µM cycloglitazone (IC), 10 mg/L insulin + 100 µM oleic acid (IO), or 10 mg/L insulin + 10 µM cycloglitazone+100 µM oleic acid (ICO). Control preadipocytes (CON) were cultured in differentiation medium (containing 5% fetal calf serum). The effects on the differentiation of Yanbian cattle preadipocytes were examined using molecular and transcriptomic techniques, including differentially expressed genes (DEGs) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis. I, IC, IO, and ICO treatments produced higher concentrations of triglycerides (TAG) and lipid droplet accumulation in preadipocytes compared with CON treatment (P < 0.05). Co-treatment of insulin and PPARγ agonists significantly increased the expression of genes involved in regulating adipogenesis and fatty acid synthesis. (P < 0.05). Differential expression analysis identified 1488, 1764, 1974 and 1368 DEGs in the I, IC, IO and ICO groups, respectively. KEGG pathway analysis revealed DEGs mainly enriched in PPAR signalling, FOXO signaling pathway and fatty acid metabolism. These results indicate that OA, as PPARγ agonist, can more effectively promote the expression of bovine lipogenesis genes and the content of TAG and adiponectin when working together with insulin, and stimulate the differentiation of bovine preadipocytes. These findings provide a basis for further screening of relevant genes and transcription factors in intramuscular fat deposition and meat quality to enhance breeding programs.


Assuntos
Adipócitos , Diferenciação Celular , Insulina , Ácido Oleico , PPAR gama , Tiazolidinedionas , Animais , Bovinos , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Insulina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Ácido Oleico/farmacologia , Adipogenia/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos
4.
Cryobiology ; 115: 104892, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593909

RESUMO

Refreezing the remaining genetic resources after in vitro fertilization (IVF) can conserve genetic materials. However, the precise damage inflicted by repeated freezing and thawing on bovine sperm and its underlying mechanism remain largely unexplored. Thus, this study investigates the impact of repeated freeze-thaw cycles on sperm. Our findings indicate that such cycles significantly reduce sperm viability and motility. Furthermore, the integrity of the sperm plasma membrane and acrosome is compromised during this process, exacerbating the advanced apoptosis triggered by oxidative stress. Additionally, transmission electron microscopy exposed severe damage to the plasma membranes of both the sperm head and tail. Notably, the "9 + 2" structure of the tail was disrupted, along with a significant decrease in the level of the axonemal protein DNAH10, leading to reduced sperm motility. IVF outcomes revealed that repeated freeze-thaw cycles considerably impair sperm fertilization capability, ultimately reducing the blastocyst rate. In summary, our research demonstrates that repeated freeze-thaw cycles lead to a decline in sperm viability and motility, attributed to oxidative stress-induced apoptosis and DNAH10-related dynamic deficiency. As a result, the utility of semen is compromised after repeated freezing.


Assuntos
Apoptose , Criopreservação , Fertilização in vitro , Congelamento , Estresse Oxidativo , Preservação do Sêmen , Motilidade dos Espermatozoides , Espermatozoides , Animais , Masculino , Bovinos , Criopreservação/veterinária , Criopreservação/métodos , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides/fisiologia , Fertilização in vitro/veterinária , Congelamento/efeitos adversos , Membrana Celular , Sobrevivência Celular , Acrossomo
5.
Sci Rep ; 14(1): 6959, 2024 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521811

RESUMO

Abdominal aortic aneurysm (AAA) is a deadly, permanent ballooning of the aortic artery. Pharmacological and genetic studies have pointed to multiple proteins, including microsomal prostaglandin E2 synthase-1 (mPGES-1), as potentially promising targets. However, it remains unknown whether administration of an mPGES-1 inhibitor can effectively attenuate AAA progression in animal models. There are still no FDA-approved pharmacological treatments for AAA. Current research stresses the importance of both anti-inflammatory drug targets and rigor of translatability. Notably, mPGES-1 is an inducible enzyme responsible for overproduction of prostaglandin E2 (PGE2)-a well-known principal pro-inflammatory prostanoid. Here we demonstrate for the first time that a highly selective mPGES-1 inhibitor (UK4b) can completely block further growth of AAA in the ApoE-/- angiotensin (Ang)II mouse model. Our findings show promise for the use of a mPGES-1 inhibitor like UK4b as interventional treatment of AAA and its potential translation into the clinical setting.


Assuntos
Aneurisma da Aorta Abdominal , Animais , Camundongos , Angiotensina II , Aorta/metabolismo , Aneurisma da Aorta Abdominal/tratamento farmacológico , Aneurisma da Aorta Abdominal/metabolismo , Dinoprostona/uso terapêutico , Modelos Animais de Doenças , Prostaglandina-E Sintases/genética , Prostaglandinas
6.
Opt Lett ; 49(5): 1281-1284, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426993

RESUMO

We report high-performance germanium-on-insulator (GeOI) waveguide photodetectors (WGPDs) for electronic-photonic integrated circuits (EPICs) operating at telecommunication wavelengths. The GeOI samples were fabricated using layer transfer and wafer-bonding techniques, and a high-quality Ge active layer was achieved. Planar lateral p-i-n WGPDs were fabricated and characterized, and they exhibited a low dark current of 0.1 µA. Strain-induced alterations in the optical properties were observed, resulting in an extended photodetection range up to λ = 1638 nm. This range encompasses crucial telecommunication bands. The WGPDs exhibited a high responsivity of 0.56 A/W and a high detectivity of D ∗ = 1.87 ×109cmHz1/2W - 1 at 1550 nm. A frequency-response analysis revealed that increasing the bias voltage from -1 to -9 V enhances the 3-dB bandwidth from 31 to 49 MHz. This study offers a comprehensive understanding of GeOI WGPDs, fostering high-performance EPICs with implications for telecommunications and beyond.

7.
Medicine (Baltimore) ; 103(6): e37038, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335431

RESUMO

Colorectal cancer (CRC) remains a significant global health concern, as characterized by its high mortality rate ranking second among all the leading causes of death. The liver serves as the primary site of CRC metastasis, and the occurrence of liver metastasis is a significant contributor to mortality among patients diagnosed with CRC. The survival rate of patients with colorectal liver metastasis has significantly increased with the advancement of comprehensive tumor therapy. However, radical surgery remains the key factor. Since there are frequently multiple liver metastases, which are prone to recurrence after surgery, it is crucial to preserve as much liver parenchyma as possible without affecting the prognosis. The issue of surgical margins plays a crucial role in this regard. In this review, we begin by examining the occurrence of positive surgical margins in liver metastases of patients diagnosed with CRC. We aim to define positive margins in hepatic surgery, examine the relationship between margins and prognosis and establish a foundation for future research in this field.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Margens de Excisão , Hepatectomia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/patologia , Prognóstico
8.
Sensors (Basel) ; 24(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38400421

RESUMO

GeSn alloys have recently emerged as complementary metal-oxide-semiconductor (CMOS)-compatible materials for optoelectronic applications. Although various photonic devices based on GeSn thin films have been developed, low-dimensional GeSn quantum structures with improved efficiencies hold great promise for optoelectronic applications. This study theoretically analyses Ge-capped GeSn pyramid quantum dots (QDs) on Ge substrates to explore their potential for such applications. Theoretical models are presented to calculate the effects of the Sn content and the sizes of the GeSn QDs on the strain distributions caused by lattice mismatch, the band structures, transition energies, wavefunctions of confined electrons and holes, and transition probabilities. The bandgap energies of the GeSn QDs decrease with the increasing Sn content, leading to higher band offsets and improved carrier confinement, in addition to electron-hole wavefunction overlap. The GeSn QDs on the Ge substrate provide crucial type-I alignment, but with a limited band offset, thereby decreasing carrier confinement. However, the GeSn QDs on the Ge substrate show a direct bandgap at higher Sn compositions and exhibit a ground-state transition energy of ~0.8 eV, rendering this system suitable for applications in the telecommunication window (1550 nm). These results provide important insights into the practical feasibility of GeSn QD systems for optoelectronic applications.

9.
Nano Lett ; 24(8): 2596-2602, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38251930

RESUMO

Sepsis, a life-threatening inflammatory response, demands economical, accurate, and rapid detection of biomarkers during the critical "golden hour" to reduce the patient mortality rate. Here, we demonstrate a cost-effective waveguide-enhanced nanogold-linked immunosorbent assay (WENLISA) based on nanoplasmonic waveguide biosensors for the rapid and sensitive detection of procalcitonin (PCT), a sepsis-related inflammatory biomarker. To enhance the limit of detection (LOD), we employed sandwich assays using immobilized capture antibodies and detection antibodies conjugated to gold nanoparticles to bind the target analyte, leading to a significant evanescent wave redistribution and strong nanoplasmonic absorption near the waveguide surface. Experimentally, we detected PCT for a wide linear response range of 0.1 pg/mL to 1 ng/mL with a record-low LOD of 48.7 fg/mL (3.74 fM) in 8 min. Furthermore, WENLISA has successfully identified PCT levels in the blood plasma of patients with sepsis and healthy individuals, offering a promising technology for early sepsis diagnosis.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Sepse , Humanos , Pró-Calcitonina , Imunoadsorventes , Ouro , Sepse/diagnóstico , Biomarcadores , Anticorpos Imobilizados
10.
Int J Biol Macromol ; 259(Pt 2): 129313, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216012

RESUMO

Prolyl endopeptidases (PEP) from Sphingomonas capsulata (sc) and Myxococcus xanthus (mx) selectively degrade gluten peptides in vitro, offering a potential therapeutic strategy for celiac disease. However, the mechanisms governing the interaction of these enzymes with their substrates remain unclear. In this study, conventional molecular dynamics simulations with a microsecond timescale and targeted molecular dynamics simulations were performed to investigate the native states of mxPEP and scPEP enzymes, as well as their allosteric binding with a representative substrate, namely, Z-Ala-Pro-p-nitroanilide (pNA). The simulations reveal that the native scPEP is in an open state, while the native mxPEP is in a closed state. When pNA approaches a closed mxPEP, it binds to an allosteric pocket located at the first and second ß-sheet of the ß-propeller domain, inducing the opening of this enzyme. Neither enzyme is active in the open or partly-open states. Enzymatic activity is enabled only when the catalytic pocket in the closed state fully accommodates the substrates. The internal capacity of the catalytic pocket of PEP in the closed state determines the maximum size of the gluten peptides that the enzymes can catalyze. The present work provides essential molecular dynamics information for the redesign or engineering of PEP enzymes.


Assuntos
Doença Celíaca , Prolil Oligopeptidases , Humanos , Prolil Oligopeptidases/metabolismo , Serina Endopeptidases/química , Simulação de Dinâmica Molecular , Glutens/química , Peptídeos/química
11.
Sci Rep ; 14(1): 927, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195724

RESUMO

Cocaine dependence is a serious world-wide public health problem without an FDA-approved pharmacotherapy. We recently designed and discovered a highly efficient long-acting cocaine hydrolase CocH5-Fc(M6). The present study examined the effectiveness and duration of CocH5-Fc(M6) in blocking interoceptive effects of cocaine by performing cocaine discrimination tests in rats, demonstrating that the duration of CocH5-Fc(M6) in blocking cocaine discrimination was dependent on cocaine dose and CocH5-Fc(M6) plasma concentration. Particularly, a dose of 3 mg/kg CocH5-Fc(M6) effectively attenuated discriminative stimulus effects of 10 mg/kg cocaine, cumulative doses of 10 and 32 mg/kg cocaine, and cumulative doses of 10, 32 and 56 mg/kg cocaine by ≥ 20% for 41, 19, and 10 days, and completely blocked the discriminative stimulus effects for 30, 13, and 5 days with corresponding threshold plasma CocH5-Fc(M6) concentrations of 15.9, 72.2, and 221 nM, respectively, under which blood cocaine concentration was negligible. Additionally, based on the data obtained, cocaine discrimination model is more sensitive than the locomotor activity to reveal cocaine effects and that CocH5-Fc(M6) itself has no long-term toxicity regarding behavioral activities such as lever pressing and food consumption in rats, further demonstrating that CocH5-Fc(M6) has the desired properties as a promising therapeutic candidate for prevenance of cocaine dependence.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Animais , Ratos , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Cocaína/farmacologia , Hidrolases de Éster Carboxílico , Locomoção
12.
J Phys Chem B ; 127(50): 10723-10729, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38063500

RESUMO

A combined computational and experimental study has been carried out to explore and test a quantitative correlation relationship between the relative catalytic efficiency (RCE) of human butyrylcholinesrase (BChE) mutant-catalyzed hydrolysis of substrate (-)-cocaine and the total hydrogen bonding energy (tHBE) of the carbonyl oxygen of the substrate with the oxyanion hole of the enzyme in the modeled transition-state structure (TS1), demonstrating a satisfactory linear correlation relationship between ln(RCE) and tHBE. The satisfactory correlation relationship has led us to computationally predict and experimentally confirm new human BChE mutants that have a further improved catalytic activity against (-)-cocaine, including the most active one (the A199S/F227S/S287G/A328W/Y332G mutant) with a 2790-fold improved catalytic efficiency (kcat/KM = 2.5 × 109 min-1 M-1) compared to the wild-type human BChE. Compared to the reference mutant (the A199S/S287G/A328W/Y332G mutant) tested in the reported clinical development of an enzyme therapy for cocaine dependence treatment, this new mutant (with a newly predicted additional F227S mutation) has an improved catalytic efficiency against (-)-cocaine by ∼2.6-fold. The good agreement between the computational and experimental ln(RCE) values suggests that the obtained correlation relationship is robust for computational prediction. A similar correlation relationship could also be explored in studying BChE or other serine hydrolases/esterases with an oxyanion hole stabilizing the carbonyl oxygen in the rate-determining reaction step of the enzymatic hydrolysis of other substrates.


Assuntos
Butirilcolinesterase , Cocaína , Humanos , Butirilcolinesterase/genética , Butirilcolinesterase/química , Catálise , Cocaína/química , Ligação de Hidrogênio , Hidrólise , Modelos Moleculares , Oxigênio
13.
Sensors (Basel) ; 23(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687845

RESUMO

Group-IV GeSn photodetectors (PDs) compatible with standard complementary metal-oxide-semiconductor (CMOS) processing have emerged as a new and non-toxic infrared detection technology to enable a wide range of infrared applications. The performance of GeSn PDs is highly dependent on the Sn composition and operation temperature. Here, we develop theoretical models to establish a simple rule of thumb, namely "GeSn-rule 23", to describe GeSn PDs' dark current density in terms of operation temperature, cutoff wavelength, and Sn composition. In addition, analysis of GeSn PDs' performance shows that the responsivity, detectivity, and bandwidth are highly dependent on operation temperature. This rule provides a simple and convenient indicator for device developers to estimate the device performance at various conditions for practical applications.

14.
Sensors (Basel) ; 23(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37687985

RESUMO

Group IV alloys of GeSn have been extensively investigated as a competing material alternative in shortwave-to-mid-infrared photodetectors (PDs). The relatively large defect densities present in GeSn alloys are the major challenge in developing practical devices, owing to the low-temperature growth and lattice mismatch with Si or Ge substrates. In this paper, we comprehensively analyze the impact of defects on the performance of GeSn p-i-n homojunction PDs. We first present our theoretical models to calculate various contributing components of the dark current, including minority carrier diffusion in p- and n-regions, carrier generation-recombination in the active intrinsic region, and the tunneling effect. We then analyze the effect of defect density in the GeSn active region on carrier mobilities, scattering times, and the dark current. A higher defect density increases the dark current, resulting in a reduction in the detectivity of GeSn p-i-n PDs. In addition, at low Sn concentrations, defect-related dark current density is dominant, while the generation dark current becomes dominant at a higher Sn content. These results point to the importance of minimizing defect densities in the GeSn material growth and device processing, particularly for higher Sn compositions necessary to expand the cutoff wavelength to mid- and long-wave infrared regime. Moreover, a comparative study indicates that further improvement of the material quality and optimization of device structure reduces the dark current and thereby increases the detectivity. This study provides more realistic expectations and guidelines for evaluating GeSn p-i-n PDs as a competitor to the III-V- and II-VI-based infrared PDs currently on the commercial market.

15.
Front Pharmacol ; 14: 1243243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637420

RESUMO

Background: Ketosis is one of the most frequent and costly metabolic disorders in high-producing dairy cows, and negatively associated with the health and reproductive performance of bovine. Ketosis is mainly caused by the accumulation of ketone body ß-hydroxybutyric acid and its diagnosis is based on ß-hydroxybutyrate (ßHB) concentration in blood. Methods: In this study, we investigated the effects of ßHB on bovine oocyte maturation in the concentration of subclinical (1.2 mM) ßHB and clinical (3.6 mM). Results: The results showed ßHB disrupted bovine oocyte maturation and development capacity. Further analysis showed that ßHB induced oxidative stress and mitochondrial dysfunction, as indicated by the increased level of reactive oxygen species (ROS), disrupted mitochondrial structure and distribution, and depolarized membrane potential. Furthermore, oxidative stress triggered early apoptosis, as shown by the enhanced levels of Caspase-3 and Annexin-V. Moreover, 3.6 mM ßHB induced the disruption of the pyruvate dehydrogenase (PDH) activity, showing with the decrease of the global acetylation modification and the increase of the abnormal spindle rate. Conclusion: Our study showed that ßHB in subclinical/clinical concentration had toxic effects on mitochondrial function and PDH activity, which might affect energy metabolism and epigenetic modification of bovine oocytes and embryos.

16.
J Med Chem ; 66(17): 12479-12498, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37623046

RESUMO

Opioid use disorder (OUD) has emerged as a significant global public health issue, necessitating the discovery of new medications. In this study, we propose a deep generative model that combines a stochastic differential equation (SDE)-based diffusion model with a pretrained autoencoder. The molecular generator enables efficient generation of molecules that target multiple opioid receptors, including mu, kappa, and delta. Additionally, we assess the ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties of the generated molecules to identify druglike compounds. We develop a molecular optimization approach to enhance the pharmacokinetic properties of some lead compounds. Advanced binding affinity predictors were built using molecular fingerprints, including autoencoder embeddings, transformer embeddings, and topological Laplacians. Our process yields druglike molecules that can be used in highly focused experimental studies to further evaluate their pharmacological effects. Our machine learning platform serves as a valuable tool for designing effective molecules to address OUD.


Assuntos
Aprendizado de Máquina , Transtornos Relacionados ao Uso de Opioides , Humanos , Difusão , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Receptores Opioides
17.
ArXiv ; 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37396606

RESUMO

Opioid Use Disorder (OUD) has emerged as a significant global public health issue, with complex multifaceted conditions. Due to the lack of effective treatment options for various conditions, there is a pressing need for the discovery of new medications. In this study, we propose a deep generative model that combines a stochastic differential equation (SDE)-based diffusion modeling with the latent space of a pretrained autoencoder model. The molecular generator enables efficient generation of molecules that are effective on multiple targets, specifically the mu, kappa, and delta opioid receptors. Furthermore, we assess the ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties of the generated molecules to identify drug-like compounds. To enhance the pharmacokinetic properties of some lead compounds, we employ a molecular optimization approach. We obtain a diverse set of drug-like molecules. We construct binding affinity predictors by integrating molecular fingerprints derived from autoencoder embeddings, transformer embeddings, and topological Laplacians with advanced machine learning algorithms. Further experimental studies are needed to evaluate the pharmacological effects of these drug-like compounds for OUD treatment. Our machine learning platform serves as a valuable tool in designing and optimizing effective molecules for addressing OUD.

18.
BioDrugs ; 37(5): 649-674, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37464099

RESUMO

In recent years, machine learning (ML) techniques have garnered considerable interest for their potential use in accelerating the rate of drug discovery. With the emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, the utilization of ML has become even more crucial in the search for effective antiviral medications. The pandemic has presented the scientific community with a unique challenge, and the rapid identification of potential treatments has become an urgent priority. Researchers have been able to accelerate the process of identifying drug candidates, repurposing existing drugs, and designing new compounds with desirable properties using machine learning in drug discovery. To train predictive models, ML techniques in drug discovery rely on the analysis of large datasets, including both experimental and clinical data. These models can be used to predict the biological activities, potential side effects, and interactions with specific target proteins of drug candidates. This strategy has proven to be an effective method for identifying potential coronavirus disease 2019 (COVID-19) and other disease treatments. This paper offers a thorough analysis of the various ML techniques implemented to combat COVID-19, including supervised and unsupervised learning, deep learning, and natural language processing. The paper discusses the impact of these techniques on pandemic drug development, including the identification of potential treatments, the understanding of the disease mechanism, and the creation of effective and safe therapeutics. The lessons learned can be applied to future outbreaks and drug discovery initiatives.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Aprendizado de Máquina , Antivirais/uso terapêutico , Reposicionamento de Medicamentos
19.
Opt Lett ; 48(7): 1626-1629, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221726

RESUMO

The study of all-group-IV SiGeSn lasers has opened a new avenue to Si-based light sources. SiGeSn heterostructure and quantum well lasers have been successfully demonstrated in the past few years. It has been reported that, for multiple quantum well lasers, the optical confinement factor plays an important role in the net modal gain. In previous studies, adding a cap layer was proposed to increase the optical mode overlap with the active region and thereby improve the optical confinement factor of Fabry-Perot cavity lasers. In this work, SiGeSn/GeSn multiple quantum well (4-well) devices with various cap layer thicknesses, i.e., 0 (no cap), 190, 250, and 290 nm, are grown using a chemical vapor deposition reactor and characterized via optical pumping. While no-cap and thinner-cap devices only show spontaneous emission, the two thicker-cap devices exhibit lasing up to 77 K, with an emission peak at 2440 nm and a threshold of 214 kW/cm2 (250 nm cap device). The clear trend in device performance disclosed in this work provides guidance in device design for electrically injected SiGeSn quantum well lasers.

20.
Int J Neuropsychopharmacol ; 26(6): 415-425, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37208298

RESUMO

BACKGROUND: Phosphodiesterase 2A (PDE2A) represents a novel target for new therapies addressing psychiatric disorders. To date, the development of PDE2A inhibitors suitable for human clinical evaluation has been hampered by the poor brain accessibility and metabolic stability of the available compounds. METHODS: Corticosterone (CORT)-induced neuronal cell lesion and restraint stress mouse model were used to measure the neuroprotective effect in cells and antidepressant-like behavior in mice. RESULTS: The cell-based assay showed that both Hcyb1 and PF were potent in protecting cells against stress hormone CORT insults by stimulating cAMP and cGMP signaling in hippocampal cells (HT-22). Administration of both compounds before treatment of CORT to cells increased cAMP/cGMP, VASP phosphorylation at Ser239 and Ser157, cAMP response element binding protein phosphorylation at Ser133, and brain derived neurotrophic factor BDNF expression. Further in vivo study showed that both Hcyb1 and PF displayed -antidepressant- and anxiolytic-like effects against restraint stress as indicated by reduced immobility time in the forced swimming and tail suspension tasks as well as increased open arm entries and time spent in open arms and holes visit in elevated plus maze and hole-board tests, respectively. The biochemical study confirmed that these antidepressant- and anxiolytic-like effects of Hcyb1 and PF were related to cAMP and cGMP signaling in the hippocampus. CONCLUSIONS: The results extend the previous studies and validate that PDE2A is a tractable target for drug development in the treatment of emotional disorders such as depression and anxiety.


Assuntos
Ansiolíticos , Inibidores de Fosfodiesterase , Camundongos , Humanos , Animais , Inibidores de Fosfodiesterase/farmacologia , Depressão/psicologia , Ansiolíticos/farmacologia , Antidepressivos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/induzido quimicamente , Hipocampo , Diester Fosfórico Hidrolases/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Comportamento Animal , Modelos Animais de Doenças
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