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1.
J Am Chem Soc ; 146(7): 4771-4782, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38323928

RESUMEN

High-density polyethylene (HDPE) is a widely used commercial plastic due to its excellent mechanical properties, chemical resistance, and water vapor barrier properties. However, less than 10% of HDPE is mechanically recycled, and the chemical recycling of HDPE is challenging due to the inherent strength of the carbon-carbon backbone bonds. Here, we report chemically recyclable linear and branched HDPE with sparse backbone ester groups synthesized from the transesterification of telechelic polyethylene macromonomers. Stoichiometrically self-balanced telechelic polyethylenes underwent transesterification polymerization to produce the PE-ester samples with high number-average molar masses of up to 111 kg/mol. Moreover, the transesterification polymerization of the telechelic polyethylenes and the multifunctional diethyl 5-(hydroxymethyl)isophthalate generated branched PE-esters. Thermal and mechanical properties of the PE-esters were comparable to those of commercial HDPE and tunable through control of the ester content in the backbone. In addition, branched PE-esters showed higher levels of melt strain hardening compared with linear versions. The PE-ester was depolymerized into telechelic macromonomers through straightforward methanolysis, and the resulting macromonomers could be effectively repolymerized to generate a high molar mass recycled PE-ester sample. This is a new and promising method for synthesizing and recycling high-molar-mass linear and branched PE-esters, which are competitive with HDPE and have easily tailorable properties.

2.
Curr Issues Mol Biol ; 46(4): 3470-3483, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38666948

RESUMEN

Atopic dermatitis (AD), marked by intense itching and eczema-like lesions, is a globally increasing chronic skin inflammation. Kahweol, a diterpene that naturally occurs in coffee beans, boasts anti-inflammatory, antioxidative, and anti-cancer properties. This research explores the anti-inflammatory action of kahweol on HaCaT human keratinocytes stimulated by tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), focusing on key signal transduction pathways. Our results demonstrate that kahweol markedly reduces the production of IL-1ß, IL-6, C-X-C motif chemokine ligand 8, and macrophage-derived chemokine in TNF-α/IFN-γ-activated HaCaT cells. Furthermore, it curtails the phosphorylation of key proteins in the mitogen-activated protein kinase (MAPK) pathways, including c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38. Additionally, kahweol impedes the phosphorylation and nuclear translocation of the NF-κB p65 subunit and constrains its DNA-binding capability. It also hampers the phosphorylation, nuclear translocation, and DNA-binding activities of signal transducer and activator of transcription 1 (STAT1) and STAT3. Collectively, these findings suggest that kahweol hinders the generation of cytokines and chemokines in inflamed keratinocytes by inhibiting the MAPK, NF-κB, and STAT cascades. These insights position kahweol as a promising agent for dermatological interventions, especially in managing inflammatory skin conditions such as AD.

3.
Small ; 20(25): e2306585, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38212281

RESUMEN

Compact but precise feature-extracting ability is core to processing complex computational tasks in neuromorphic hardware. Physical reservoir computing (RC) offers a robust framework to map temporal data into a high-dimensional space using the time dynamics of a material system, such as a volatile memristor. However, conventional physical RC systems have limited dynamics for the given material properties, restricting the methods to increase their dimensionality. This study proposes an integrated temporal kernel composed of a 2-memristor and 1-capacitor (2M1C) using a W/HfO2/TiN memristor and TiN/ZrO2/Al2O3/ZrO2/TiN capacitor to achieve higher dimensionality and tunable dynamics. The kernel elements are carefully designed and fabricated into an integrated array, of which performances are evaluated under diverse conditions. By optimizing the time dynamics of the 2M1C kernel, each memristor simultaneously extracts complementary information from input signals. The MNIST benchmark digit classification task achieves a high accuracy of 94.3% with a (196×10) single-layer network. Analog input mapping ability is tested with a Mackey-Glass time series prediction, and the system records a normalized root mean square error of 0.04 with a 20×1 readout network, the smallest readout network ever used for Mackey-Glass prediction in RC. These performances demonstrate its high potential for efficient temporal data analysis.

5.
J Org Chem ; 89(5): 3102-3110, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38364274

RESUMEN

An approach to 2,3-benzotropone from 1-benzosuberone via palladium(II)-catalyzed aerobic dehydrogenation was developed. This method first provided a catalytic route to various 2,3-benzotropones from their corresponding 1-benzosuberones in good yields. In addition, the reaction could be applied to a one-pot Diels-Alder reaction with maleimide, providing a complex benzobicyclo[3.2.2]nonenone in ≤90% yield. Kinetic analysis supporting our proposed mechanism was also performed, underscoring the robustness of the developed synthetic pathway.

6.
Cereb Cortex ; 33(8): 4806-4814, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36156637

RESUMEN

The medial prefrontal cortex (mPFC) has been implicated in regulating resistance to the effects of acute uncontrollable stress. We previously showed that mPFC-lesioned animals exhibit impaired object recognition memory after acute exposure to a brief stress that had no effect in normal animals. Here, we used designer receptors exclusively activated by designer drugs to determine how modulating mPFC activity affects recognition-memory performance under stressful conditions. Specifically, animals with chemogenetic excitation or inhibition of the mPFC underwent either a brief ineffective stress (20-min restraint + 20 tail shocks) or a prolonged effective stress (60-min restraint + 60 tail shocks). Subsequent recognition memory tests showed that animals with chemogenetic mPFC inhibition exposed to brief stress showed impairment in an object recognition memory task, whereas those with chemogenetic mPFC excitation exposed to prolonged stress did not. Thus, the present findings the decreased mPFC activity exacerbates acute stress effects on memory function whereas increased mPFC activity counters these stress effects provide evidence that the mPFC bidirectionally modulates stress resistance.


Asunto(s)
Disfunción Cognitiva , Memoria , Corteza Prefrontal , Reconocimiento en Psicología , Estrés Fisiológico , Estrés Psicológico , Animales , Masculino , Ratas , Clozapina/análogos & derivados , Clozapina/farmacología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/prevención & control , Electrochoque/psicología , Memoria/efectos de los fármacos , Memoria/fisiología , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/fisiología , Ratas Sprague-Dawley , Reconocimiento en Psicología/efectos de los fármacos , Reconocimiento en Psicología/fisiología , Restricción Física/fisiología , Estrés Fisiológico/fisiología , Estrés Psicológico/complicaciones , Estrés Psicológico/fisiopatología , Factores de Tiempo
7.
Int J Mol Sci ; 25(11)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38892350

RESUMEN

Periodontitis is an inflammatory disease caused by Porphyromonas gingivalis (P. gingivalis) in the oral cavity. This periodontal disease causes damage to the periodontal ligament and alveolar bone and can cause tooth loss, but there is no definite treatment yet. In this study, we investigated the possibility of using no-ozone cold plasma to safely treat periodontitis in the oral cavity. First, human gingival fibroblasts (HGFs) were treated with P. gingivalis-derived lipopolysaccharide (PG-LPS) to induce an inflammatory response, and then the anti-inflammatory effect of NCP was examined, and a study was conducted to identify the mechanism of action. Additionally, the anti-inflammatory effect of NCP was verified in rats that developed an inflammatory response similar to periodontitis. When NCP was applied to PG-LPS-treated HGFs, the activities of inflammatory proteins and cytokines were effectively inhibited. It was confirmed that the process of denaturing the medium by charged particles of NCP is essential for the anti-inflammatory effect of NCP. Also, it was confirmed that repeated treatment of periodontitis rats with NCP effectively reduced the inflammatory cells and osteoclast activity. As a result, this study suggests that NCP can be directly helpful in the treatment of periodontitis in the future.


Asunto(s)
Antiinflamatorios , Fibroblastos , Encía , Lipopolisacáridos , Periodontitis , Porphyromonas gingivalis , Animales , Periodontitis/microbiología , Periodontitis/tratamiento farmacológico , Ratas , Antiinflamatorios/farmacología , Humanos , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Ozono/farmacología , Gases em Plasma/farmacología , Gases em Plasma/uso terapéutico , Masculino , Citocinas/metabolismo , Modelos Animales de Enfermedad , Óxido Nítrico/metabolismo , Células Cultivadas
8.
BMC Plant Biol ; 23(1): 494, 2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37833628

RESUMEN

Excessive salinity reduces crop production and negatively impacts agriculture worldwide. We previously isolated endophytic bacterial strains from two halophytic species: Artemisia princeps and Chenopodium ficifolium. We used three bacterial isolates: ART-1 (Lysinibacillus fusiformis), ART-10 (Lysinibacillus sphaericus), and CAL-8 (Brevibacterium pityocampae) to alleviate the impact of salinity stress on rice. The impact of 160 mM NaCl salinity on rice was significantly mitigated following inoculation with these bacterial strains, resulting in increased growth and chlorophyll content. Furthermore, OsNHX1, OsAPX1, OsPIN1 and OsCATA expression was increased, but OsSOS expression was decreased. Inductively coupled plasma mass spectrometry (ICP-MS) revealed reduced K+ and Na+ levels in shoots of bacteria-inoculated plants, whereas that of Mg2+ was increased. Bacterial inoculation reduced the content of total flavonoids in rice leaves. Salinized plants inoculated with bacteria showed reduced levels of endogenous salicylic acid (SA) and abscisic acid (ABA) but increased levels of jasmonic acid (JA). In conclusion, the bacterial isolates ART-1, ART-10, and CAL-8 alleviated the adverse effect of salinity on rice growth, which justifies their use as an eco-friendly agricultural practice.


Asunto(s)
Antioxidantes , Oryza , Antioxidantes/metabolismo , Oryza/metabolismo , Estrés Salino , Bacterias , Hormonas/metabolismo , Expresión Génica , Salinidad , Estrés Fisiológico/genética
9.
Plant Physiol ; 190(4): 2366-2379, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-35944218

RESUMEN

Virus-induced gene silencing (VIGS) is a powerful tool for high-throughput analysis of gene function. Here, we developed the VIGS vector pCF93, from which expression of the cucumber fruit mottle mosaic virus genome is driven by the cauliflower mosaic virus 35S promoter to produce viral transcripts in inoculated plants. To test the utility of the pCF93 vector, we identified candidate genes related to male sterility (MS) in watermelon (Citrullus lanatus), which is recalcitrant to genetic transformation. Specifically, we exploited previously reported reference-based and de novo transcriptome data to define 38 differentially expressed genes between a male-sterile line and its fertile near-isogenic line in the watermelon cultivar DAH. We amplified 200- to 300-bp fragments of these genes, cloned them into pCF93, and inoculated DAH with the resulting VIGS clones. The small watermelon cultivar DAH enabled high-throughput screening using a small cultivation area. We simultaneously characterized the phenotypes associated with each of the 38 candidate genes in plants grown in a greenhouse. Silencing of 8 of the 38 candidate genes produced male-sterile flowers with abnormal stamens and no pollen. We confirmed the extent of gene silencing in inoculated flowers using reverse transcription-qPCR. Histological analysis of stamens from male-fertile and male-sterile floral buds and mature flowers revealed developmental defects and shrunken pollen sacs. Based on these findings, we propose that the pCF93 vector and our VIGS system will facilitate high-throughput analysis for the study of gene function in watermelons.


Asunto(s)
Citrullus , Tobamovirus , Tobamovirus/genética , Citrullus/genética , Flores/genética , Fenotipo , Silenciador del Gen , Regulación de la Expresión Génica de las Plantas
10.
Mol Breed ; 43(5): 39, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37312747

RESUMEN

The gelatinization temperature of rice is an important factor in determining the eating and cooking quality, and it affects consumer preference. The alkali digestion value (ADV) is one of the main methods used to test the quality of rice and has a high correlation with the gelatinization temperature. For the development of high-quality rice, it is important to understand the genetic basis of palatability-related traits, and QTL analysis is a statistical method linking phenotypic data and genotype data and is an effective method to explain the genetic basis of variation in complex traits. QTL mapping related to the ADV of brown and milled rice was performed using the 120 Cheongcheong/Nagdong double haploid (CNDH) line. As a result, 12 QTLs related to ADV were detected, and 20 candidate genes were selected from the RM588-RM1163 region of chromosome 6 through screening by gene function analysis. The comparison of the relative expression level of candidate genes showed that OsSS1q6 is highly expressed in CNDH lines with high ADV in both brown rice and milled rice. In addition, OsSS1q6 has high homology with the starch synthase 1 protein and interacts with various starch biosynthesis-related proteins, such as GBSSII, SBE, and APL. Therefore, we suggest that OsSS1q6 identified through QTL mapping could be one of the various genes involved in the gelatinization temperature of rice by regulating starch biosynthesis. This study can be used as basic data for breeding high-quality rice and provides a new genetic resource that can increase the palatability of rice. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01392-2.

11.
Sens Actuators B Chem ; 378: 133193, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36570722

RESUMEN

Rapid, sensitive, and specific detection of the severe acute respiratory syndrome coronavirus (SARS-CoV)- 2 during early infection is pivotal in controlling the spread and pathological progression of Coronavirus Disease 2019 (COVID-19). Thus, highly accurate, affordable, and scalable point-of-care (POC) diagnostic technologies are necessary. Herein, we developed a rapid and efficient self-directed molecular diagnostic (SdMDx) system for SARS-CoV-2. This system combines the sample preparation step, including virus enrichment and extraction processes, which involve dimethyl suberimidate dihydrochloride and diatomaceous earth functionalized with 3-aminopropyl(diethoxy)methylsilane, and the detection step using loop-mediated isothermal amplification-lateral flow assay (LAMP-LFA). Using the SdMDx system, SARS-CoV-2 could be detected within 47 min by hand without the need for any larger instruments. The SdMDx system enabled detection as low as 0.05 PFU in the culture fluid of SARS-CoV-2-infected VeroE6 cells. We validated the accuracy of the SdMDx system on 38 clinical nasopharyngeal specimens. The clinical utility of the SdMDx system for targeting the S gene of SARS-CoV-2 showed 94.4% sensitivity and 100% specificity. This system is more sensitive than antigen and antibody assays, and it minimizes the use of complicated processes and reduces contamination risks. Accordingly, we demonstrated that the SdMDx system enables a rapid, accurate, simple, efficient, and inexpensive detection of SARS-CoV-2 at home, in emergency facilities, and in low-resource sites as a pre-screening platform and POC testing through self-operation and self-diagnosis.

12.
J Chem Phys ; 159(8)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37606327

RESUMEN

The performance of sustainable polymers can be modified and enhanced by incorporating functional groups in the backbone of the polymer chain that increases intermolecular interactions, thus impacting the thermal properties of the material. However, in-depth studies on the role of intermolecular interactions on the crystallization of these polymers are still needed. This work aims to ascertain whether incorporating functional groups able to induce intermolecular interactions can be used as a suitable systematic strategy to modify the polymer thermal properties and crystallization kinetics. Thus, amide and additional ester groups have been incorporated into aliphatic polyesters (PEs). The impact of intermolecular interactions on the melting and crystallization behavior, crystallization kinetics, and crystalline structure has been determined. Functional groups that form strong intermolecular interactions increase both melting and crystallization temperatures but retard the crystallization kinetics. Selecting appropriate functional groups allows tuning the crystallinity degree, which can potentially improve the mechanical properties and degradability in semicrystalline materials. The results demonstrate that it is possible to tune the thermal transitions and the crystallization kinetics of PEs independently by varying their chemical structure.

13.
Mar Drugs ; 21(7)2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37504935

RESUMEN

Brown algae comprise up to 2000 species with wide dissemination in temperate zones. A comprehensive untargeted metabolic profiling guided by molecular networking of three uninvestigated Red-Sea-derived brown algae, namely Sirophysalis trinodis, Polycladia myrica, and Turbinaria triquetra, led to the identification of over 115 metabolites categorized as glycerolipids, fatty acids, sterol lipids, sphingolipids, and phospholipids. The three algae exhibited low-to-moderate antioxidant capacity using DPPH and ABTS assays. Preliminary in vitro antiproliferative studies showed that the algal extracts displayed high cytotoxic activity against a panel of cancer cell lines. The most potent activity was recorded against MCF-7 with IC50 values of 51.37 ± 1.19, 63.44 ± 1.13, and 59.70 ± 1.22 µg/mL for S. trinodis, P. myrica, and T. triquetra, respectively. The cytotoxicity of the algae was selective to MCF-7 without showing notable effects on the proliferation of normal human WISH cells. Morphological studies revealed that the algae caused cell shrinkage, increased cellular debris, triggered detachment, cell rounding, and cytoplasmic condensation in MCF-7 cancer cells. Mechanistic investigations using flow cytometry, qPCR, and Western blot showed that the algae induced apoptosis, initiated cell cycle arrest in the sub-G0/G1 phase, and inhibited the proliferation of cancer cells via increasing mRNA and protein expression of p53, while reducing the expression of PI3K, Akt, and mTOR.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Cromatografía Liquida , Océano Índico , Proliferación Celular , Espectrometría de Masas en Tándem , Serina-Treonina Quinasas TOR/metabolismo , Células MCF-7 , Apoptosis , Línea Celular Tumoral
14.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38069217

RESUMEN

Rice plant height is an agricultural trait closely related to biomass, lodging tolerance, and yield. Identifying quantitative trait loci (QTL) regions related to plant height regulation and developing strategies to screen potential candidate genes can improve agricultural traits in rice. In this study, a double haploid population (CNDH), derived by crossing 'Cheongcheong' and 'Nagdong' individuals, was used, and a genetic map was constructed with 222 single-sequence repeat markers. In the RM3482-RM212 region on chromosome 1, qPh1, qPh1-1, qPh1-3, qPh1-5, and qPh1-6 were identified for five consecutive years. The phenotypic variance explained ranged from 9.3% to 13.1%, and the LOD score ranged between 3.6 and 17.6. OsPHq1, a candidate gene related to plant height regulation, was screened in RM3482-RM212. OsPHq1 is an ortholog of gibberellin 20 oxidase 2, and its haplotype was distinguished by nine SNPs. Plants were divided into two groups based on their height, and tall and short plants were distinguished and clustered according to the expression level of OsPHq1. QTLs and candidate genes related to plant height regulation, and thus, biomass regulation, were screened and identified in this study, but the molecular mechanism of the regulation remains poorly known. The information obtained in this study will help develop molecular markers for marker-assisted selection and breeding through rice plant height control.


Asunto(s)
Oryza , Sitios de Carácter Cuantitativo , Humanos , Mapeo Cromosómico , Oryza/genética , Fitomejoramiento , Fenotipo
15.
J Biol Chem ; 296: 100040, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33162394

RESUMEN

The Hippo pathway controls organ size and tissue homeostasis through the regulation of cell proliferation and apoptosis. However, the exact molecular mechanisms underpinning Hippo pathway regulation are not fully understood. Here, we identify a new component of the Hippo pathway: coronin 7 (CORO7), a coronin protein family member that is involved in organization of the actin cytoskeleton. pod1, the Drosophila ortholog of CORO7, genetically interacts with key Hippo pathway genes in Drosophila. In mammalian cells, CORO7 is required for the activation of the Hippo pathway in response to cell-cell contact, serum deprivation, and cytoskeleton damage. CORO7 forms a complex with the core components of the pathway and functions as a scaffold for the Hippo core kinase complex. Collectively, these results demonstrate that CORO7 is a key scaffold controlling the Hippo pathway via modulating protein-protein interactions.


Asunto(s)
Proteínas de Drosophila/fisiología , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Drosophila , Células HEK293 , Humanos , Transducción de Señal/genética
16.
Anal Chem ; 94(50): 17422-17430, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36454685

RESUMEN

As observed in the COVID-19 pandemic, RNA viruses continue to rapidly evolve through mutations. In the absence of effective therapeutics, early detection of new severely pathogenic viruses and quarantine of infected people are critical for reducing the spread of the viral infections. However, conventional detection methods require a substantial amount of time to develop probes specific to new viruses, thereby impeding immediate response to the emergence of viral pathogens. In this study, we identified multiple types of viruses by obtaining the spectral fingerprint of their surface proteins with probe-free surface-enhanced Raman scattering (SERS). In addition, the SERS-based method can remarkably distinguish influenza virus variants with several surface protein point mutations from their parental strain. Principal component analysis (PCA) of the SERS spectra systematically captured the key Raman bands to distinguish the variants. Our results show that the combination of SERS and PCA can be a promising tool for rapid detection of newly emerging mutant viruses without a virus-specific probe.


Asunto(s)
COVID-19 , Orthomyxoviridae , Virus , Humanos , Espectrometría Raman/métodos , Mutación Puntual , Pandemias
17.
BMC Infect Dis ; 22(1): 330, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379181

RESUMEN

BACKGROUND: Respiratory infections among children, particularly community-acquired pneumonia (CAP), is a major disease with a high frequency among outpatient and inpatient visits. The causes of CAP vary depending on individual susceptibility, the epidemiological characteristics of the community, and the season. We performed this study to establish a nationwide surveillance network system and identify the causative agents for CAP and antibiotic resistance in Korean children with CAP. METHODS: The monitoring network was composed of 28 secondary and tertiary medical institutions. Upper and lower respiratory samples were assayed using a culture or polymerase chain reaction (PCR) from August 2018 to May 2020. RESULTS: A total of 1023 cases were registered in patients with CAP, and PCR of atypical pneumonia pathogens revealed 422 cases of M. pneumoniae (41.3%). Respiratory viruses showed a positivity rate of 65.7% by multiplex PCR test, and human rhinovirus was the most common virus, with 312 cases (30.5%). Two hundred sixty four cases (25.8%) were isolated by culture, including 131 cases of S. aureus (12.8%), 92 cases of S. pneumoniae (9%), and 20 cases of H. influenzae (2%). The cultured, isolated bacteria may be colonized pathogen. The proportion of co-detection was 49.2%. The rate of antibiotic resistance showed similar results as previous reports. CONCLUSIONS: This study will identify the pathogens that cause respiratory infections and analyze the current status of antibiotic resistance to provide scientific evidence for management policies of domestic respiratory infections. Additionally, in preparation for new epidemics, including COVID-19, monitoring respiratory infections in children and adolescents has become more important, and research on this topic should be continuously conducted in the future.


Asunto(s)
COVID-19 , Infecciones Comunitarias Adquiridas , Neumonía por Mycoplasma , Adolescente , Niño , Infecciones Comunitarias Adquiridas/microbiología , Humanos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Staphylococcus aureus
18.
Int J Med Sci ; 19(12): 1732-1742, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36313226

RESUMEN

Background: This experimental research aimed to determine whether No-ozone Cold Plasma (NCP) has regenerative effect on crushed injured sensory nerves in a rat model (Wistar A) and to evaluate whether NCP can be used as an alternative treatment method for sensory nerve injury in the oral-maxillofacial region. Methods: A total of 10 Wistar A rats were used for this experiment. They were divided into three groups according to whether the mental nerve of the left mandible was injured and NCP was applied or not: group 1 (n=3) (non-mental nerve damage, non-MD) - the left mental nerve was exposed and non-damaged; group 2 (n=3) (mental nerve damage, MD) - the left mental nerve was exposed and damaged, NCP was not applied; and group 3 (n=4) (mental nerve damage and NCP, MD-NCP) - the left mental nerve was exposed and damaged, NCP was applied with regular intervals (three times a week). Results: For the behavior analysis, von Frey test was used. Furthermore, the nerve tissues were examined with hematoxylin and eosin (H&E) staining, and the extent of neurorecovery was evaluated with the immunofluorescence staining of certain markers. The behavioral analysis showed that the function recovery sensory nerve was faster in group 3 (MD-NCP). In the histomorphologic and immunofluorescence analyses, the expression of the factors involved in neurorecovery was much higher in group 3 than in group 2 (MD). Conclusions: The expeditious recovery of sensory nerve function as well as the higher expression of the factors indicating nerve function recovery in the NCP-treated group suggest that NCP has a positive effect on regeneration after sensory nerve crushing injury. Therefore, in the case of sensory impairment of the oral-maxillofacial region, no-ozone cold plasma can be applied for therapeutic effect.


Asunto(s)
Lesiones por Aplastamiento , Lesiones del Nervio Mandibular , Ozono , Traumatismos de los Nervios Periféricos , Gases em Plasma , Ratas , Animales , Nervio Ciático/lesiones , Regeneración Nerviosa , Gases em Plasma/uso terapéutico , Ozono/farmacología , Ozono/uso terapéutico , Ratas Wistar , Traumatismos de los Nervios Periféricos/tratamiento farmacológico
19.
J Chem Phys ; 156(14): 144902, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35428378

RESUMEN

The origin of melt memory effects associated with semicrystalline polymers and the physical parameters involved in this process have been widely studied in the literature. However, a comprehensive understanding of the role of intermolecular interactions on melt memory is still being developed. For this purpose, we have considered aliphatic polyesters and we have incorporated amide and additional ester groups. Inserting these additional functional groups, the strength of the intermolecular interactions increases widening the melt memory effect. Not only the presence of the functional groups but also the position of these groups in the repeating unit plays a role in the melt memory effect as it impacts the strength of the intermolecular interactions in the crystals. The study of the effect of intermolecular interactions has been extended to successive self-nucleation and annealing thermal fractionation experiments to explore for the first time the role of intermolecular forces on the fractionation capacity of linear polymers. We demonstrated that intermolecular interactions act as intrinsic defects interrupting the crystallizable chain length, thus facilitating thermal fractionation. Overall, this work sheds light on the role of intermolecular interactions on the crystallization behavior of a series of aliphatic polyesters.

20.
Appl Opt ; 61(34): 10116-10120, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36606772

RESUMEN

A linear-type wavelength-tunable all-polarization-maintaining fiber mode-locked laser is proposed for the first time, to our knowledge, and is implemented with an Er-doped fiber and polarization-maintaining fiber components. The tuning range of the center wavelength is from 1533.7 nm to 1565.6 nm. The linear-type configuration makes the proposed laser simpler and more compact, allowing it to achieve the highest repetition rate of 126.5 MHz among C-band wavelength-tunable mode-locked lasers due to its short cavity length. Also, its polarization-maintaining fiber components provide reliable operating robustness. The significant wavelength tunability and high repetition rate of the proposed laser can be expected to make it an attractive resource for various applications, including optical communications, broadband spectroscopic LIDAR, and high-precision ranging.

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