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1.
Cureus ; 16(5): e61022, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38910701

RESUMEN

Purpose This study examines the outcomes of locally advanced head and neck squamous cell carcinoma (HNSCC) following the adoption of conventional intensity-modulated radiotherapy (cIMRT) and volumetric-modulated arc therapy (VMAT) over a decade. The region under study has higher comorbidities associated with increased HNSCC incidence and poorer prognosis. Materials and methods A 10-year retrospective review of electronic medical records included 296 patients with stage III, IVA, and IVB HNSCC (American Joint Committee on Cancer, Seventh edition). Survival outcomes were compared between VMAT and cIMRT using Kaplan-Meier survival curves and adjusted for relevant demographic factors using Cox's proportional hazards model. Analysis was performed using R software (R Foundation, Vienna, Austria). Results The median age of the cohort was 63 years, comprising of 80% males. The oropharynx was the most common primary tumor site. 264 (89%) received 50Gy or higher dose radiation by either cIMRT (22%) or VMAT (67%). At five years, locoregional control (LC) and overall survival (OS) rates were 79.5% and 56.7%, respectively. VMAT showed a significant improvement in five-year OS (63.4% versus 43.8% for cIMRT, p=0.0023) but no significant difference in five-year LC (81% VMAT versus 74.5% cIMRT, p=0.17). Grade 3-4 acute toxicity was observed in 22% of patients. Conclusions VMAT and cIMRT demonstrated excellent LC in locally advanced HNSCC despite high comorbidity rates. Notably, VMAT was associated with significantly better OS compared to cIMRT. These outcomes surpass historical data, suggesting that VMAT technology may lead to improved patient outcomes. However, larger randomized controlled trials and dosimetric studies are needed to confirm these findings.

2.
Pest Manag Sci ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877352

RESUMEN

BACKGROUND: Understanding how parasitoids respond to temperature is crucial for improving biological control strategies under the context of global warming. This study examined the suitability of Myzus persicae and its parasitoid Aphidius gifuensis to varying temperature conditions, as well as the stage-specific response of A. gifuensis to high temperatures. RESULTS: High temperatures had a significant impact on the both M. persicae and A. gifuensis. When exposed to 36°C, M. persicae developed more slowly and produced smaller adults compared to control, regardless of the duration of exposure (2, 4 or 6 h); additionally, the survival rate of M. persicae nymphs sharply decreased under these conditions. Exposure to 36°C for 4 h negatively impacted the development of A. gifuensis. Female parasitoids exposed to 32°C developed into smaller adults, whereas males exposed to all three temperature levels were smaller compared to control group. Female parasitoids exposed to high temperatures, regardless of the specific heat level and duration, exhibited reduced longevity and decreased fecundity. None of the parasitoids exposed to 36°C for 6 h daily developed into adults. Heat treated during early developmental stages (2 and 4 days old) had a greater influence on parasitoid development, whereas heat treatment at 4 and 6 days old had a more significant impact on its fecundity. CONCLUSION: High temperatures not only directly affected the performance of A. gifuensis, but also exerted indirect effects by influencing the quality of the host aphids M. persicae. The deleterious effects of high temperature on larvae can persist into the adult stage, affecting the longevity and reproduction of adults. These findings are important for the utilization of A. gifuensis in the control of M. persicae in warming environments. © 2024 Society of Chemical Industry.

3.
Angew Chem Int Ed Engl ; : e202406585, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38863281

RESUMEN

Polymer electrolytes play a crucial role in advancing rechargeable magnesium batteries (RMBs) owing to their exceptional characteristics, including high flexibility, superior interface compatibility, broad electrochemical stability window, and enhanced safety features. Despite these advantages, research in this domain remains nascent, plagued by single preparation approaches and challenges associated with the compatibility between polymer electrolytes and Mg metal anode. In this study, we present a novel synthesis strategy to fabricate a glycerol α,α'-diallyl ether-3,6-dioxa-1,8-octanedithiol-based polymer electrolyte supported by glass fiber substrate (GDT@GF) through anion modification and thiol-ene click chemistry polymerization. The developed route exhibits novelty and high efficiency, leading to the production of GDT@GF membranes featuring exceptional mechanical properties, heightened ionic conductivity, elevated Mg2+ transference number, and commendable compatibility with Mg anode. The assembled modified Mo6S8||GDT@GF||Mg cells exhibit outstanding performance across a wide temperature range and address critical safety concerns, showcasing the potential for applications under extreme conditions. Our innovative preparation strategy offers a promising avenue for the advancement of polymer electrolytes in high-performance rechargeable magnesium batteries, while also opens up possibilities for future large-scale applications and the development of flexible electronic devices.

4.
Sci Transl Med ; 16(747): eadl1408, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748772

RESUMEN

Essential tremor (ET) is the most prevalent movement disorder, characterized primarily by action tremor, an involuntary rhythmic movement with a specific frequency. However, the neuronal mechanism underlying the coding of tremor frequency remains unexplored. Here, we used in vivo electrophysiology, optogenetics, and simultaneous motion tracking in the Grid2dupE3 mouse model to investigate whether and how neuronal activity in the olivocerebellum determines the frequency of essential tremor. We report that tremor frequency was encoded by the temporal coherence of population neuronal firing within the olivocerebellums of these mice, leading to frequency-dependent cerebellar oscillations and tremors. This mechanism was precise and generalizable, enabling us to use optogenetic stimulation of the deep cerebellar nuclei to induce frequency-specific tremors in wild-type mice or alter tremor frequencies in tremor mice. In patients with ET, we showed that deep brain stimulation of the thalamus suppressed tremor symptoms but did not eliminate cerebellar oscillations measured by electroencephalgraphy, indicating that tremor-related oscillations in the cerebellum do not require the reciprocal interactions with the thalamus. Frequency-disrupting transcranial alternating current stimulation of the cerebellum could suppress tremor amplitudes, confirming the frequency modulatory role of the cerebellum in patients with ET. These findings offer a neurodynamic basis for the frequency-dependent stimulation of the cerebellum to treat essential tremor.


Asunto(s)
Cerebelo , Temblor Esencial , Neuronas , Núcleo Olivar , Temblor Esencial/fisiopatología , Animales , Humanos , Núcleo Olivar/fisiopatología , Cerebelo/fisiopatología , Ratones , Masculino , Optogenética , Femenino , Estimulación Encefálica Profunda , Persona de Mediana Edad , Electroencefalografía , Anciano
5.
World J Diabetes ; 15(5): 898-913, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38766436

RESUMEN

BACKGROUND: The understanding of bile acid (BA) and unsaturated fatty acid (UFA) profiles, as well as their dysregulation, remains elusive in individuals with type 2 diabetes mellitus (T2DM) coexisting with non-alcoholic fatty liver disease (NAFLD). Investigating these metabolites could offer valuable insights into the pathophy-siology of NAFLD in T2DM. AIM: To identify potential metabolite biomarkers capable of distinguishing between NAFLD and T2DM. METHODS: A training model was developed involving 399 participants, comprising 113 healthy controls (HCs), 134 individuals with T2DM without NAFLD, and 152 individuals with T2DM and NAFLD. External validation encompassed 172 participants. NAFLD patients were divided based on liver fibrosis scores. The analytical approach employed univariate testing, orthogonal partial least squares-discriminant analysis, logistic regression, receiver operating characteristic curve analysis, and decision curve analysis to pinpoint and assess the diagnostic value of serum biomarkers. RESULTS: Compared to HCs, both T2DM and NAFLD groups exhibited diminished levels of specific BAs. In UFAs, particular acids exhibited a positive correlation with NAFLD risk in T2DM, while the ω-6:ω-3 UFA ratio demonstrated a negative correlation. Levels of α-linolenic acid and γ-linolenic acid were linked to significant liver fibrosis in NAFLD. The validation cohort substantiated the predictive efficacy of these biomarkers for assessing NAFLD risk in T2DM patients. CONCLUSION: This study underscores the connection between altered BA and UFA profiles and the presence of NAFLD in individuals with T2DM, proposing their potential as biomarkers in the pathogenesis of NAFLD.

6.
Front Cell Dev Biol ; 12: 1385041, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38784382

RESUMEN

Cell-free DNA (cfDNA), a burgeoning class of molecular biomarkers, has been extensively studied across a variety of biomedical fields. As a key component of liquid biopsy, cfDNA testing is gaining prominence in disease detection and management due to the convenience of sample collection and the abundant wealth of genetic information it provides. However, the broader clinical application of cfDNA is currently impeded by a lack of standardization in the preanalytical procedures for cfDNA analysis. A number of fundamental challenges, including the selection of appropriate preanalytical procedures, prevention of short cfDNA fragment loss, and the validation of various cfDNA measurement methods, remain unaddressed. These existing hurdles lead to difficulties in comparing results and ensuring repeatability, thereby undermining the reliability of cfDNA analysis in clinical settings. This review discusses the crucial preanalytical factors that influence cfDNA analysis outcomes, including sample collection, transportation, temporary storage, processing, extraction, quality control, and long-term storage. The review provides clarification on achievable consensus and offers an analysis of the current issues with the goal of standardizing preanalytical procedures for cfDNA analysis.

7.
Cureus ; 16(4): e58135, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38741816

RESUMEN

We report a rare case of an extremely old colorectal cancer (CRC) patient who had complete remission after liver metastasectomy and stereotactic body radiotherapy (SBRT) to lung oligometastases (OM), with good quality of life and no evidence of recurrence 12 years after the initial diagnosis. An 83-year-old male patient had a right hemicolectomy for stage pT3 pN0 adenocarcinoma of the colon. Soon he was found to have liver metastasis treated with radiofrequency ablation and then liver metastasectomy with clear margins, followed by chemotherapy in the form of FOLFIRI for six months. Six years later, positron emission tomography (PET) showed 1.6 cm OM in the left upper lobe lung. He was not considered a good candidate for surgery. We offered him SBRT 48 Gy in four fractions every other day. The lesion disappeared with no recurrence in the same location on PET and serial computed tomography (CT) scans. Three years later, PET-CT found a new OM in the left lingular lung measuring 1.2 cm. A CT-guided lung biopsy confirmed invasive adenocarcinoma favoring OM from the CRC. SBRT planning failed due to its proximity to the heart. He accepted the longer course of conventional volumetric modulated arc therapy at 60 Gy in 15 fractions with daily cone-beam CT guidance. Again, he tolerated treatment very well with no significant side effects, despite his age. He did not require any chemotherapy or other systemic treatment in the last 11 years, so he did not experience any toxicities related to such treatment. This case is important to show that old age alone should not be considered a contraindication for metastasectomy and SBRT for CRC with liver and lung OM.

8.
Inflammopharmacology ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753221

RESUMEN

Inflammatory bowel diseases (IBDs) are prevalent and debilitating diseases with limited clinical treatment strategies. Mesenchymal stem cell (MSCs) are pluripotent stem cells with self-renewal capability and multiple immunomodulatory effects, which make them a promising therapeutic approach for IBDs. Thus, optimization of MSCs regimes is crucial for their further clinical application. Wogonin, a flavonoid-like compound with extensive immunomodulatory and adjuvant effects, has been investigated as a potential pretreatment for MSCs in IBD treatment. In this study, we employed the DSS-induced acute colitis mouse model to compare the therapeutic effectiveness of MSCs in pretreated with or without wogonin and further explore the underlying mechanism. Compared to untreated MSCs, MSCwogonin (pretreated with wogonin) showed greater effectiveness in the treatment of colitis. Further experiments revealed that wogonin treatment activated the AKT signaling pathway, resulting in higher cellular glycolysis. Inhibition of AKT phosphorylation by perifosine not only decreased glycolysis but impaired the therapeutic efficiency of MSCwogonin. Consistent with these results, qPCR data indicated that wogonin treatment induced the expression of immunomodulatory molecules IL-10, IDO, and AGR1, which were reduced by perifosine. Together, our data demonstrated that wogonin preconditioning strategy further augmented the therapeutic efficacy of MSCs via promoting glycolysis, which should be a promising strategy for optimizing MSCs therapy in IBDs.

9.
J Neurol Sci ; 461: 123060, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38810429

RESUMEN

INTRODUCTION: Previous research has identified that people with cerebellar ataxia (CA) showed impaired reward-related decision-making in the Iowa Gambling Task (IGT). To investigate the mechanisms underlying this impairment, we examined CA participants' combination of performance in the IGT, which predominantly tests reward seeking, and the modified IGT (mIGT), which mainly assesses punishment avoidance. METHODS: Fifty participants with CA and one hundred controls completed the IGT and mIGT. Task performance in each of the five twenty-trial blocks was compared between groups and the learning rates were assessed with simple linear regressions. Each participant's IGT score and mIGT score were compared. RESULTS: CA participants performed worse than controls in both the IGT and the mIGT, especially in the last block (IGT: -0.24 ± 10.05 vs. 3.88 ± 10.31, p = 0.041; mIGT: 2.72 ± 7.62 vs. 8.65 ± 8.64, p < 0.001). In contrast to the controls, those with CA did not significantly improve their scores over time in either task. Controls performed better in the mIGT than the IGT, while CA participants' scores in the two tasks showed no significant difference. IGT and mIGT performance did not correlate with ataxia severity or depressive symptoms. CONCLUSION: Individuals with CA showed impaired performance in both the IGT and mIGT, which indicates disruption in both short-term reward seeking and short-term punishment avoidance. Therefore, these results suggest that reduced sensitivity to long-term consequences drives the risky decision-making in CA.


Asunto(s)
Ataxia Cerebelosa , Toma de Decisiones , Juego de Azar , Recompensa , Humanos , Masculino , Femenino , Persona de Mediana Edad , Ataxia Cerebelosa/fisiopatología , Ataxia Cerebelosa/psicología , Toma de Decisiones/fisiología , Juego de Azar/psicología , Juego de Azar/fisiopatología , Adulto , Pruebas Neuropsicológicas , Anciano
10.
Chemistry ; : e202401063, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654592

RESUMEN

14,14'-Bidibenzo[a,j]anthracenes (BDBAs) were prepared by iridium-catalyzed annulation of 5,5'-biterphenylene with alkynes. The molecular geometries of overcrowded BDBAs were verified by X-ray crystallography. The two dibenzo[a,j]anthryl moieties are connected through the sterically hindered 14 positions, resulting in highly distorted molecular halves. The conformation with a small twist angle between two molecular halves can minimize steric conflicts between the substituents at 1 and 13 positions and the carbon atoms of the central axis, as well as steric clashes between those substituents. One such example is octafluoro-substituted BDBA, where the interplanar angle between two anthryl moieties is approximately 31° (currently the lowest reported value, cf. 81° in 9,9'-bianthracene). The intramolecular interactions and electronic couplings between two molecular halves resulted in upfield 1H NMR signals, redshifted absorption and emission bands, and a reduced HOMO-LUMO gap. Photodynamic investigations on BDBAs indicated that the formation of the conventional symmetry-breaking charge transfer (SBCT) state was suspended by restricted rocking around the central C-C bond. Such a mechanism associated with this highly constrained conformation was examined for the first time.

11.
Poult Sci ; 103(6): 103617, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38547674

RESUMEN

Avian leukosis virus Subgroup J (ALV-J) exhibits high morbidity and pathogenicity, affecting approximately 20% of poultry farms. It induces neoplastic diseases and immunosuppression. Phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1), a proapoptotic mitochondrial protein in the B-cell lymphoma-2 (Bcl-2) family, plays a role in apoptosis in cancer cells. However, the connection between the PMAIP1 gene and ALV-J pathogenicity remains unexplored. This study investigates the potential impact of the PMAIP1 gene on ALV-J replication and its regulatory mechanisms. Initially, we examined PMAIP1 expression using quantitative real-time PCR (qRT-PCR) in vitro and in vivo. Furthermore, we manipulated PMAIP1 expression in chicken fibroblast cells (DF-1) and assessed its effects on ALV-J infection through qRT-PCR, immunofluorescence assay (IFA), and western blotting (WB). Our findings reveal a significant down-regulation of PMAIP1 in the spleen, lung, and kidney, coupled with an up-regulation in the bursa and liver of ALV-J infected chickens compared to uninfected ones. Additionally, DF-1 cells infected with ALV-J displayed a notable up-regulation of PMAIP1 at 6, 12, 24, 48, 74, and 108 h. Over-expression of PMAIP1 enhanced ALV-J replication, interferon expression, and proinflammatory factors. Conversely, interference led to contrasting results. Furthermore, we observed that PMAIP1 promotes virus replication by modulating mitochondrial function. In conclusion, the PMAIP1 gene facilitates virus replication by regulating mitochondrial function, thereby enriching our understanding of mitochondria-related genes and their involvement in ALV-J infection, offering valuable insights for avian leukosis disease resistance strategies.


Asunto(s)
Virus de la Leucosis Aviar , Leucosis Aviar , Pollos , Mitocondrias , Enfermedades de las Aves de Corral , Replicación Viral , Animales , Virus de la Leucosis Aviar/fisiología , Enfermedades de las Aves de Corral/virología , Enfermedades de las Aves de Corral/genética , Mitocondrias/metabolismo , Leucosis Aviar/virología , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo
12.
Proc Natl Acad Sci U S A ; 121(7): e2306775121, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38315850

RESUMEN

Limiting global warming to 2 °C requires urgent action on land-based mitigation. This study evaluates the biogeochemical and biogeophysical implications of two alternative land-based mitigation scenarios that aim to achieve the same radiative forcing. One scenario is primarily driven by bioenergy expansion (SSP226Lu-BIOCROP), while the other involves re/afforestation (SSP126Lu-REFOREST). We find that overall, SSP126Lu-REFOREST is a more efficient strategy for removing CO2 from the atmosphere by 2100, resulting in a net carbon sink of 242 ~ 483 PgC with smaller uncertainties compared to SSP226Lu-BIOCROP, which exhibits a wider range of -78 ~ 621 PgC. However, SSP126Lu-REFOREST leads to a relatively warmer planetary climate than SSP226Lu-BIOCROP, and this relative warming can be intensified in certain re/afforested regions where local climates are not favorable for tree growth. Despite the cooling effect on a global scale, SSP226Lu-BIOCROP reshuffles regional warming hotspots, amplifying summer temperatures in vulnerable tropical regions such as Central Africa and Southeast Asia. Our findings highlight the need for strategic land use planning to identify suitable regions for re/afforestation and bioenergy expansion, thereby improving the likelihood of achieving the intended climate mitigation outcomes.

13.
Zool Res ; 45(2): 263-274, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38287907

RESUMEN

Neurodegenerative diseases (NDs) are a group of debilitating neurological disorders that primarily affect elderly populations and include Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). Currently, there are no therapies available that can delay, stop, or reverse the pathological progression of NDs in clinical settings. As the population ages, NDs are imposing a huge burden on public health systems and affected families. Animal models are important tools for preclinical investigations to understand disease pathogenesis and test potential treatments. While numerous rodent models of NDs have been developed to enhance our understanding of disease mechanisms, the limited success of translating findings from animal models to clinical practice suggests that there is still a need to bridge this translation gap. Old World non-human primates (NHPs), such as rhesus, cynomolgus, and vervet monkeys, are phylogenetically, physiologically, biochemically, and behaviorally most relevant to humans. This is particularly evident in the similarity of the structure and function of their central nervous systems, rendering such species uniquely valuable for neuroscience research. Recently, the development of several genetically modified NHP models of NDs has successfully recapitulated key pathologies and revealed novel mechanisms. This review focuses on the efficacy of NHPs in modeling NDs and the novel pathological insights gained, as well as the challenges associated with the generation of such models and the complexities involved in their subsequent analysis.


Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Humanos , Animales , Chlorocebus aethiops , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/terapia , Enfermedades Neurodegenerativas/veterinaria , Animales Modificados Genéticamente , Modelos Animales de Enfermedad , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/veterinaria , Macaca mulatta
14.
J Obstet Gynaecol Res ; 50(4): 740-745, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38204147

RESUMEN

Out of the total cases of cervical cancer, brain metastases (BMs) are relatively rare, with an estimated incidence rate of 0.63% (range: 0.1%-2.2%). Additionally, BMs prognosis remains poor, and the average patient survival time following a BM diagnosis is 3 to 5 months. Few studies have addressed the effect of programmed cell death-1 inhibitors against BMs in cervical cancer, although they are an established option for recurrent/metastatic disease. Hence, we report a case involving a 54-year-old post-surgery patient with cervical cancer with a body mass index of 19.5 kg/m2 and Eastern Collaborative Oncology Group (ECOG) performance status of 3; the disease recurred with BMs 1 year later. Intensity-modulated radiation therapy concurrent with temozolomide and bevacizumab was initiated, following which zimberelimab immunotherapy combined with anlotinib was administered to extend tumor control. The patient had a progression-free survival duration of 10 months, the tumor response was assessed as a partial response based on the evaluation criteria for solid tumors (RECIST1.1), and the ECOG status improved to 1 after therapy. These findings suggest that immunotherapy-based combination therapy following radiotherapy may be a good choice for patients with cervical cancer and BMs.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Cuello Uterino , Femenino , Humanos , Persona de Mediana Edad , Neoplasias del Cuello Uterino/tratamiento farmacológico , Recurrencia Local de Neoplasia , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Anticuerpos Monoclonales Humanizados/uso terapéutico
15.
Chemistry ; 30(11): e202303523, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-37997021

RESUMEN

A new series of biaryls, bi-linear-terphenylenes (BLTPs), were prepared using the tert-butyllithium-mediated cyclization as the key synthetic step. The three-dimensional structures of the studied compounds were verified using X-ray crystallography and DFT calculations. Tetraaryl(ethynyl)-substituted BLTPs are highly crowded molecules, and the internal rotation around the central C-C bond is restricted due to a high barrier (>50 kcal/mol). These structures contain several aryl/terphenylenyl/aryl sandwiches, where the through-space π-π (TSPP) interactions are strongly reflected in the shielding of 1 H NMR chemical shifts, reduction of oxidation potentials, increasing aromaticity of the central six-membered ring and decreasing antiaromaticity of the four-membered rings in a terphenylenyl moiety based on NICS(0) and iso-chemical shielding surfaces. Despite the restricted C-C bond associated intramolecular TSPP interactions for BLTPs in the ground state, to our surprise, the electronic coupling between two linear terphenylenes (LTPs) in BLTPs in the excited state is weak, so that the excited-state behavior is dominated by the corresponding monomeric LTPs. In other words, all BLTPs undergo ultrafast relaxation dynamics via strong exciton-vibration coupling, acting as a blue-light absorber with essentially no emission.

16.
Adv Sci (Weinh) ; 11(7): e2304332, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38032118

RESUMEN

Microfluidic 3D cell culture devices that enable the recapitulation of key aspects of organ structures and functions in vivo represent a promising preclinical platform to improve translational success during drug discovery. Essential to these engineered devices is the spatial patterning of cells from different tissue types within a confined microenvironment. Traditional fabrication strategies lack the scalability, cost-effectiveness, and rapid prototyping capabilities required for industrial applications, especially for processes involving thermoplastic materials. Here, an approach to pattern fluid guides inside microchannels is introduced by establishing differential hydrophilicity using pressure-sensitive adhesives as masks and a subsequent selective coating with a biocompatible polymer. Optimal coating conditions are identified using polyvinylpyrrolidone, which resulted in rapid and consistent hydrogel flow in both the open-chip prototype and the fully bonded device containing additional features for medium perfusion. The suitability of the device for dynamic 3D cell culture is tested by growing human hepatocytes in the device under controlled fluid flow for a 14-day period. Additionally, the study demonstrated the potential of using the device for pharmaceutical high-throughput screening applications, such as predicting drug-induced liver injury. The approach offers a facile strategy of rapid prototyping thermoplastic microfluidic organ chips with varying geometries, microstructures, and substrate materials.


Asunto(s)
Hepatocitos , Microfluídica , Humanos , Microfluídica/métodos , Técnicas de Cultivo Tridimensional de Células , Hidrogeles
17.
FASEB J ; 38(1): e23397, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38149908

RESUMEN

Toxoplasma gondii relies heavily on the de novo pyrimidine biosynthesis pathway for fueling the high uridine-5'-monophosphate (UMP) demand during parasite growth. The third step of de novo pyrimidine biosynthesis is catalyzed by dihydroorotase (DHO), a metalloenzyme that catalyzes the reversible condensation of carbamoyl aspartate to dihydroorotate. Here, functional analyses of TgDHO reveal that tachyzoites lacking DHO are impaired in overall growth due to decreased levels of UMP, and the noticeably growth restriction could be partially rescued after supplementation with uracil or high concentrations of L-dihydroorotate in vitro. When pyrimidine salvage pathway is disrupted, both DHOH35A and DHOD284E mutant strains proliferated much slower than DHO-expressing parasites, suggesting an essential role of both TgDHO His35 and Asp284 residues in parasite growth. Additionally, DHO deletion causes the limitation of bradyzoite growth under the condition of uracil supplementation or uracil deprivation. During the infection in mice, the DHO-deficient parasites are avirulent, despite the generation of smaller tissue cysts. The results reveal that TgDHO contributes to parasite growth both in vitro and in vivo. The significantly differences between TgDHO and mammalian DHO reflect that DHO can be exploited to produce specific inhibitors targeting apicomplexan parasites. Moreover, potential DHO inhibitors exert beneficial effects on enzymatic activity of TgDHO and T. gondii growth in vitro. In conclusion, these data highlight the important role of TgDHO in parasite growth and reveal that it is a promising anti-parasitic target for future control of toxoplasmosis.


Asunto(s)
Parásitos , Toxoplasma , Animales , Ratones , Dihidroorotasa , Pirimidinas/farmacología , Uracilo , Uridina Monofosfato , Mamíferos
18.
Cerebellum ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066397

RESUMEN

Recent findings in animals have challenged the traditional view of the cerebellum solely as the site of motor control, suggesting that the cerebellum may also be important for learning to predict reward from trial-and-error feedback. Yet, evidence for the role of the cerebellum in reward learning in humans is lacking. Moreover, open questions remain about which specific aspects of reward learning the cerebellum may contribute to. Here we address this gap through an investigation of multiple forms of reward learning in individuals with cerebellum dysfunction, represented by cerebellar ataxia cases. Nineteen participants with cerebellar ataxia and 57 age- and sex-matched healthy controls completed two separate tasks that required learning about reward contingencies from trial-and-error. To probe the selectivity of reward learning processes, the tasks differed in their underlying structure: while one task measured incremental reward learning ability alone, the other allowed participants to use an alternative learning strategy based on episodic memory alongside incremental reward learning. We found that individuals with cerebellar ataxia were profoundly impaired at reward learning from trial-and-error feedback on both tasks, but retained the ability to learn to predict reward based on episodic memory. These findings provide evidence from humans for a specific and necessary role for the cerebellum in incremental learning of reward associations based on reinforcement. More broadly, the findings suggest that alongside its role in motor learning, the cerebellum likely operates in concert with the basal ganglia to support reinforcement learning from reward.

19.
Cancer Innov ; 2(6): 448-462, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38125763

RESUMEN

Long noncoding RNAs (lncRNAs) are a class of nonprotein-coding transcripts that are longer than 200 nucleotides. LINC00355 is a lncRNA located on chromosome 13q21.31 and is consistently upregulated in various cancers. It regulates the expression of downstream genes at both transcriptional and posttranscriptional levels, including eight microRNAs (miR-15a-5p, miR-34b-5p, miR-424-5p, miR-1225, miR-217-5p, miR-6777-3p, miR-195, and miR-466) and three protein-coding genes (ITGA2, RAD18, and UBE3C). LINC00355 plays a role in regulating various biological processes such as cell cycle progression, proliferation, apoptosis, epithelial-mesenchymal transition, invasion, and metastasis of cancer cells. It is involved in the regulation of the Wnt/ß-catenin signaling pathway and p53 signaling pathway. Upregulation of LINC00355 has been identified as a high-risk factor in cancer patients and its increased expression is associated with poorer overall survival, recurrence-free survival, and disease-free survival. LINC00355 upregulation has been linked to several unfavorable clinical characteristics, including advanced tumor node metastasis and World Health Organization stages, reduced Karnofsky Performance Scale scores, increased tumor size, greater depth of invasion, and more extensive lymph node metastasis. LINC00355 induces chemotherapy resistance in cancer cells by regulating five downstream genes, namely HMGA2, ABCB1, ITGA2, WNT10B, and CCNE1 genes. In summary, LINC00355 is a potential oncogene with great potential as a diagnostic marker and therapeutic target for cancer.

20.
Artículo en Inglés | MEDLINE | ID: mdl-37878252

RESUMEN

The coronavirus disease 2019 (COVID-19) epidemic has given a warning that it is important to explore the rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in clinical specimens or environmental samples for public health strategies and future variants. The surface-enhanced Raman spectroscopy (SERS) technique was demonstrated to achieve this goal. However, the consistency of signals originating from the poor compatibility of virions with SERS hotspots remains a key scientific challenge for the practical applications of SERS. Herein, we develop a SERS platform for the ultrasensitive and rapid detection of SARS-CoV-2 antigen within 20 min by the combination of a highly consistent SERS substrate and a supervised deep learning algorithm. A V-shaped resonant cavity array (VRC) substrate was fabricated to trap SARS-CoV-2 virions in the periodic V cavity array and stimulate the integral SERS signal of the virus via a resonance coupling effect. Benefiting from the unique architecture of the VRC substrate, we were able to directly detect the SARS-CoV-2 virus with high sensitivity and high consistency. These excellent performances enabled us to identify five different kinds of SARS-CoV-2 variants and detect SARS-CoV-2 from clinical and environmental samples with high accuracies.

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