Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 219
Filtrar
1.
Sci Rep ; 14(1): 10502, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714849

RESUMO

We aimed to conduct a proof-of-concept study of INV-001 in visualizing lymphatic vessels and nodes without venous contamination and to determine the optimal dose condition of INV-001 for magnetic resonance lymphangiography (MRL) in healthy beagles. MRL was performed using a 3.0-Tesla (T) whole body clinical magnetic resonance imaging (MRI) scanner. A dose-finding study of INV-001 for MRL in beagles (N = 6) was carried out according to an adaptive optimal dose finding design. For the reproducibility study (N = 6), MRL was conducted at selected INV-001 doses (0.056 and 0.112 mg Fe/kg) with a 15 mM concentration. Additionally, an excretion study (N = 3) of INV-001 was conducted by analyzing T1, T2, and T2* maps of the liver and kidney 48 h post-administration. INV-001 administration at doses of 0.056 and 0.112 mg Fe/kg (concentration: 15 mM) consistently demonstrated the visualization of contrast-enhanced lymphatic vessels and nodes without venous contamination in the beagles. The contrast enhancement effect was highest at 30 min after INV-001 administration, then gradually decreasing. No toxicity-related issues were identified during the study. After 48 h, the T1, T2, and T2* values in the liver and both kidneys were found to be comparable to the pre-administration values, indicating thorough INV-001 excretion. The optimal dosing conditions of INV-001 for MRL for contrast-enhanced visualization of lymphatic vessels and nodes exclusively with no venous contamination in beagles was determined to be 0.056 mg Fe/kg with a 15 mM concentration.


Assuntos
Meios de Contraste , Vasos Linfáticos , Linfografia , Imageamento por Ressonância Magnética , Animais , Cães , Imageamento por Ressonância Magnética/métodos , Linfografia/métodos , Meios de Contraste/administração & dosagem , Vasos Linfáticos/diagnóstico por imagem , Masculino , Reprodutibilidade dos Testes , Feminino , Linfonodos/diagnóstico por imagem , Estudo de Prova de Conceito
2.
Biomedicines ; 12(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38397986

RESUMO

Chemical exchange saturation transfer with glutamate (GluCEST) imaging is a novel technique for the non-invasive detection and quantification of cerebral Glu levels in neuromolecular processes. Here we used GluCEST imaging and 1H magnetic resonance spectroscopy (1H MRS) to assess in vivo changes in Glu signals within the hippocampus in a rat model of depression induced by a forced swim test. The forced swimming test (FST) group exhibited markedly reduced GluCEST-weighted levels and Glu concentrations when examined using 1H MRS in the hippocampal region compared to the control group (GluCEST-weighted levels: 3.67 ± 0.81% vs. 5.02 ± 0.44%, p < 0.001; and Glu concentrations: 6.560 ± 0.292 µmol/g vs. 7.133 ± 0.397 µmol/g, p = 0.001). Our results indicate that GluCEST imaging is a distinctive approach to detecting and monitoring Glu levels in a rat model of depression. Furthermore, the application of GluCEST imaging may provide a deeper insight into the neurochemical involvement of glutamate in various psychiatric disorders.

3.
Sci Rep ; 14(1): 1214, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216610

RESUMO

Due to global climate change, crops are certainly confronted with a lot of abiotic and biotic stress factors during their growth that cause a serious threat to their development and overall productivity. Among different abiotic stresses, salt and drought are considered the most devastating stressors with serious impact on crop's yield stability. Here, the current study aimed to elucidate how melatonin works in regulating plant biomass, oxidative stress, antioxidant defense system, as well as the expression of genes related to salt and drought stress in rice plants. Eight groups of rice plants (3 replicates, 5 plants each) underwent varied treatments: control, melatonin, salt, drought, salt + drought, salt + melatonin, drought + melatonin, and salt + drought + melatonin. Melatonin (100 µM) was alternately applied a week before stress exposure; salt stress received 100 mM NaCl every 3 days for 3 weeks, and drought stress involved 10% PEG. Young leaves were randomly sampled from each group. The results showed that melatonin treatment markedly reduces salt and drought stress damage by promoting root, shoot length, fresh and dry weight, increasing chlorophyll contents, and inhibiting excessive production of oxidative stress markers. Salt and drought stress significantly decreased the water balance, and damaged cell membrane by reducing relative water contents and increasing electrolyte leakage. However, melatonin treated rice plants showed high relative water contents and low electrolyte leakage. Under salt and drought stress conditions, exogenous application of melatonin boosted the expression level of salt and drought stress responsive genes like OsSOS, OsNHX, OsHSF and OsDREB in rice plants. Taken together, our results reveal that melatonin treatment significantly increases salt and drought tolerance of rice plants, by increasing plant biomass, suppressing ROS accumulation, elevating antioxidants defense efficiency, and up-regulating the expression of salt and drought stress responsive genes.


Assuntos
Melatonina , Oryza , Melatonina/farmacologia , Melatonina/metabolismo , Secas , Oryza/metabolismo , Resistência à Seca , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Estresse Fisiológico/genética , Eletrólitos/metabolismo , Água/metabolismo
4.
Sensors (Basel) ; 23(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38067863

RESUMO

Liquid scintillators are extensively employed as targets in neutrino experiments and in medical radiography. Perovskite nanocrystals are recognized for their tunable emission spectra and high photoluminescence quantum yields. In this study, we investigated the feasibility of using perovskites as an alternative to fluor, a substance that shifts the wavelengths. The liquid scintillator candidates were synthesized by doping perovskite nanocrystals with emission wavelengths of 450, 480, and 510 nm into fluor PPO with varying nanocrystal concentrations in a toluene solvent. The several properties of the perovskite nanocrystal-doped liquid scintillator were measured and compared with those of a secondary wavelength shifter, bis-MSB. The emission spectra of the perovskite nanocrystal-doped liquid scintillator exhibited a distinct monochromatic wavelength, indicating energy transfer from PPO to the perovskite nanocrystals. Using a 60Co radioactive source setup with two photomultiplier tubes (PMTs), the light yields, pulse shape, and wavelength shifts of the scintillation events were measured. The light yields were evaluated based on the observed Compton edges from γ-rays, and compared across the synthesized samples. A decrease (or increase) in area-normalized PMT pulse height was observed at higher perovskite nanocrystal (or PPO) concentrations. The results demonstrated the sufficient potential of perovskite nanocrystals as an alternative to traditional wavelength shifters in a liquid scintillator.

5.
Animals (Basel) ; 13(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38136876

RESUMO

Although the use of incision-free endoscopy for foreign body (FB) removal in dogs and cats has been extensively documented, its application in birds remains limited. Thus, we present the endoscopic removal of gastrointestinal (GI) FBs from psittacine birds, employing different patient positioning and anesthesia methods. Two blue-and-yellow macaws (Ara ararauna) and a Triton cockatoo (Cacatua galerita triton) were examined. X-ray imaging revealed FBs situated in the proventriculus in each case. The FBs, all identified as feeding tubes, were safely removed using grasping forceps during the endoscopic procedure, and no severe complications occurred. Based on the outcomes of each operation, the most suitable patient position may be ventral recumbency rather than dorsal recumbency, with the use of a mask or endotracheal intubation, depending on the anticipated operation time. However, a larger number of cases would be necessary to confirm the optimal patient positioning and anesthesia method.

6.
ACS Omega ; 8(45): 43130-43138, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024696

RESUMO

The increase in the speed of aircraft causes a thermal load in the system. A cooling system is needed to solve this. Proactively, research is being conducted to cool the thermal load through the endothermic reaction of aircraft fuel. The decomposition of thermally stable fuel was performed using a lanthanide-modified zeolite as a catalyst, which was coated onto metal foam and the inner wall of a tube reactor to confirm the endothermic characteristics of the catalytic decomposition reaction. When a cerium-modified zeolite was used, the heat sink was increased to 1100Btu/lb and showed excellent performance for the cracking reaction.

7.
Biomedicines ; 11(11)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-38001911

RESUMO

Target identification is a crucial process in drug development, aiming to identify key proteins, genes, and signal pathways involved in disease progression and their relevance in potential therapeutic interventions. While C-C chemokine receptor 8 (CCR8) has been investigated as a candidate anti-cancer target, comprehensive multi-omics analyzes across various indications are limited. In this study, we conducted an extensive bioinformatics analysis integrating genomics, proteomics, and transcriptomics data to establish CCR8 as a promising anti-cancer drug target. Our approach encompassed data collection from diverse knowledge resources, gene function analysis, differential gene expression profiling, immune cell infiltration assessment, and strategic prioritization of target indications. Our findings revealed strong correlations between CCR8 and specific cancers, notably Breast Invasive Carcinoma (BRCA), Colon Adenocarcinoma (COAD), Head and Neck Squamous Cell Carcinoma (HNSC), Rectum adenocarcinoma (READ), Stomach adenocarcinoma (STAD), and Thyroid carcinoma (THCA). This research advances our understanding of CCR8 as a potential target for anti-cancer drug development, bridging the gap between molecular insights and creating opportunities for personalized treatment of solid tumors.

8.
Int J Mol Sci ; 24(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003491

RESUMO

The increasing frequency of processed food consumption has led to the higher ingestion of sugar, increasing the risk of chronic diseases, such as obesity. Yeast hydrolysates (YHs) inhibit body fat accumulation. However, the action mechanism of YH in relation to high-sugar diet-induced obesity is still unclear. Therefore, this study aimed to evaluate the biological effects of YH on lipid accumulation and verify behavioral changes and carbohydrate metabolic gene regulation in high-sugar diet-fed fruit flies. Adult male flies (Drosophila melanogaster; 2-5 days old) were exposed to 20% sucrose for obesity induction. In high-sugar-fed Drosophila, the effect of YH was compared with that of yeast extract. The effects of YH on body conditions and lipid droplet size were quantified and analyzed. Behavioral factors were evaluated by analyzing circadian rhythm patterns and neurotransmitter content, and a molecular approach was used to analyze the expression of metabolism-related genes. Dietary supplementation with YH did not reduce total sugar content, but significantly decreased the triglyceride (TG) levels in Drosophila. A behavioral analysis showed that the total number of night-time activities increased significantly with YH treatment in a dose-dependent manner. In addition, YH effectively regulated the gene expression of insulin-like peptides related to carbohydrate metabolism as well as genes related to lipogenesis. The TG content was significantly reduced at a YH concentration of 0.5%, confirming that the active compound in YH effectively suppresses fat accumulation. These findings support that YH is a potential anti-obesity food material via regulating carbohydrate metabolism in Drosophila.


Assuntos
Drosophila melanogaster , Drosophila , Masculino , Animais , Drosophila/genética , Drosophila melanogaster/metabolismo , Obesidade/genética , Obesidade/metabolismo , Leveduras , Sacarose/metabolismo , Dieta , Lipídeos
9.
Dev Cell ; 58(19): 1950-1966.e8, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37816329

RESUMO

Newly synthesized proteins in the endoplasmic reticulum (ER) are sorted by coat protein complex II (COPII) at the ER exit site en route to the Golgi. Under cellular stresses, COPII proteins become targets of regulation to control the transport. Here, we show that the COPII outer coat proteins Sec31 and Sec13 are selectively sequestered into the biomolecular condensate of SCOTIN/SHISA-5, which interferes with COPII vesicle formation and inhibits ER-to-Golgi transport. SCOTIN is an ER transmembrane protein with a cytosolic intrinsically disordered region (IDR), which is required and essential for the formation of condensates. Upon IFN-γ stimulation, which is a cellular condition that induces SCOTIN expression and condensation, ER-to-Golgi transport was inhibited in a SCOTIN-dependent manner. Furthermore, cancer-associated mutations of SCOTIN perturb its ability to form condensates and control transport. Together, we propose that SCOTIN impedes the ER-to-Golgi transport through its ability to form biomolecular condensates at the ER membrane.


Assuntos
Retículo Endoplasmático , Proteínas de Transporte Vesicular , Proteínas de Transporte Vesicular/metabolismo , Transporte Biológico , Transporte Proteico/fisiologia , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo
10.
BMC Plant Biol ; 23(1): 494, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37833628

RESUMO

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.


Assuntos
Antioxidantes , Oryza , Antioxidantes/metabolismo , Oryza/metabolismo , Estresse Salino , Bactérias , Hormônios/metabolismo , Expressão Gênica , Salinidade , Estresse Fisiológico/genética
11.
Heliyon ; 9(9): e19367, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809851

RESUMO

Background: Vitamin D deficiency is common in pregnant women. Some studies have linked vitamin D deficiency to obstetric complications such as gestational hypertension, gestational diabetes, and preterm birth. Therefore, the objective of this study is to investigate the potential impact of vitamin D deficiency during pregnancy on both perinatal and long-term outcomes. Methods: In this retrospective study, conducted between 2017 and 2021, we analyzed the data of 1079 singleton pregnant women with no medical or surgical complications prior to pregnancy. We evaluated obstetric and perinatal outcomes, as well as neurodevelopmental outcomes using Bayley-III tests, Gross Motor Function Measure, or chart review. Results: The maternal serum vitamin D level in the first trimester was 18.2 ± 9.0 ng/mL. Vitamin D deficiency (<20 ng/mL) was found in 308 (62.0%) women in the first trimester, of which 288 women (26.7%) were in the very deficient group (<10 ng/mL). There were no differences in maternal age, body mass index, and previous preterm birth between the group with vitamin D < 10 ng/mL and ≥10 ng/mL group. There were also no differences in the rates of gestational hypertension, gestational diabetes, and preterm birth between the two groups, except for the rate of preterm birth before 37 weeks of gestation, which was significantly higher in the very deficient group (adjusted odds ratios [aOR] = 7.78, 95%CI [2.23-27.12], p = 0.001). In the very deficient group, the risk of developmental delay was also higher (aOR = 4.28, 95%CI [1.40-13.05], p = 0.011). Conclusions: This is the first study to analyze the effects of maternal vitamin D deficiency during pregnancy on both long-term developmental outcomes and perinatal prognosis. Vitamin D deficiency, defined as a level lower than 10 ng/mL in the first trimester, may increase the risk of preterm birth and developmental delay in children.

12.
Foods ; 12(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37761175

RESUMO

This study aimed to investigate the impact of yeast hydrolysate (YH) on lipogenesis, elucidate its mechanistic action, and identify the active compounds responsible for its anti-adipogenic effects. YH (2 mg/mL) significantly reduced Oil Red O-stained lipids. YH (2 mg/mL) also downregulated C/EBPß and upregulated KLF2, both of which are early adipogenic factors. Moreover, YH (2 mg/mL) decreased C/EBPα, PPARγ, FABP4, FAS, ACC, and HMGCR mRNA expression. Additionally, YH significantly downregulated SEBP1c and SREBP2 and their target genes, which govern fatty acid and cholesterol metabolism; however, 2 mg/mL YH had a greater suppressive effect on SREBP1c than on SREBP2. YH (2 mg/mL) also significantly reduced the mRNA level of G6PD and malic enzyme, which are enzymes that synthesize NADPH for lipid synthesis, compared with the control. Furthermore, 1-methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acid (MTCA) was identified as the active compound with anti-adipogenic effects using solvent fractionation and chromatographic analysis of YH, and 1.1 µg/mL MTCA significantly downregulated SREBP1c/SREBP2 mRNAs by 47.8% and 69.2%, respectively, along with the target genes FAS, ACC, and HMGCR by 79.0%, 77.0%, and 40.9%, respectively. Collectively, YH effectively suppressed adipogenic lipid storage by downregulating SREBP- and NADPH-synthesizing genes. These findings suggest that YH containing MTCA has the potential to act as an anti-obesity agent.

13.
Plants (Basel) ; 12(14)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37514267

RESUMO

The number of corn cultivars that have been improved using genetically modified technology continues to increase. However, concerns about the unintentional release of living-modified organisms (LMOs) into the environment still exist. Specifically, there are cases where LMO crops grown as fodder are released into the environment and form a volunteer plant community, which raises concerns about their safety. In this study, we analyzed the possibility of weediness and volunteer plants' occurrence when GMO fodder corn grains distributed in Korea are unintentionally released into the environment. Volunteer plants' occurrence was investigated by directly sowing grains in an untreated field. The results showed that the germination rate was extremely low, and even if a corn seed germinated, it could not grow into an adult plant and would die due to weed competition. In addition, the germination rate of edible and fodder grains was affected by temperature (it was high at 20 °C and 30 °C but low at 40 °C and extremely low at 10 °C), and it was higher in the former than in the latter. And the germination rate was higher in Daehakchal (edible corn grains) than in Gwangpyeongok (fodder corn grains). The environmental risk assessment data obtained in this study can be used for future evaluations of the weediness potential of crops and the development of volunteer plant suppression technology in response to unintentional GMO release.

14.
Biology (Basel) ; 12(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37508400

RESUMO

The expression of the placental growth factor (PGF) in cancer cells and the tumor microenvironment can contribute to the induction of angiogenesis, supporting cancer cell metabolism by ensuring an adequate blood supply. Angiogenesis is a key component of cancer metabolism as it facilitates the delivery of nutrients and oxygen to rapidly growing tumor cells. PGF is recognized as a novel target for anti-cancer treatment due to its ability to overcome resistance to existing angiogenesis inhibitors and its impact on the tumor microenvironment. We aimed to integrate bioinformatics evidence using various data sources and analytic tools for target-indication identification of the PGF target and prioritize the indication across various cancer types as an initial step of drug development. The data analysis included PGF gene function, molecular pathway, protein interaction, gene expression and mutation across cancer type, survival prognosis and tumor immune infiltration association with PGF. The overall evaluation was conducted given the totality of evidence, to target the PGF gene to treat the cancer where the PGF level was highly expressed in a certain tumor type with poor survival prognosis as well as possibly associated with poor tumor infiltration level. PGF showed a significant impact on overall survival in several cancers through univariate or multivariate survival analysis. The cancers considered as target diseases for PGF inhibitors, due to their potential effects on PGF, are adrenocortical carcinoma, kidney cancers, liver hepatocellular carcinoma, stomach adenocarcinoma, and uveal melanoma.

15.
ACS Omega ; 8(21): 18743-18750, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37273586

RESUMO

Surface modification of inorganic nanoparticles is critical for the quality and performance of pigments, cosmetics, and composite materials. We covered the titanium dioxide nanoparticles' surface with 2-(acetoacetoxy) ethyl methacrylate, a polymerizable chelating agent. Through the in situ polymerization procedure, this molecule's ß-ketoester moiety quickly coordinated with the metal atoms on titanium dioxide nanoparticles, and its methacrylate group formed homogeneous coating layers. This coating layer significantly reduced the photocatalytic activity of titanium dioxide nanoparticles and prevented their aggregation. This nanoparticle dispersion showed low viscosity up to the solid content of 60% (w/w) in the liquid dispersant. As a result, it increased the UV screening performance and dispersion stability. Additionally, this coating layer widened the absorption spectrum of titanium dioxide and could change the color of nanoparticles from pale yellow to brown. It can also be helpful for cosmetic applications.

16.
Plants (Basel) ; 12(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37375908

RESUMO

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of anti-cancer drugs. The main symptoms often include sensory disturbances and neuropathic pain, and currently there is no effective treatment for this condition. This study aimed to investigate the suppressive effects of magnolin, an extracellular signal-regulated kinase (ERK) inhibitor substance derived from a 95% EtOH extract of the seeds of Magnolia denudata, on the symptoms of CIPN. A taxol-based anti-cancer drug paclitaxel (PTX) was repeatedly injected (2 mg/kg/day, total 8 mg/kg) into mice to induce CIPN. A neuropathic pain symptom was assessed using a cold allodynia test that scores behaviors of licking and shaking paw after plantar administration of acetone drop. Magnolin was administered intraperitoneally (0.1, 1, or 10 mg/kg) and behavioral changes to acetone drop were measured. The effect of magnolin administration on ERK expression in the dorsal root ganglion (DRG) was investigated using western blot analysis. The results showed that the repeated injections of PTX induced cold allodynia in mice. Magnolin administration exerted an analgesic effect on the PTX-induced cold allodynia and inhibited the ERK phosphorylation in the DRG. These results suggest that magnolin could be developed as an alternative treatment to suppress paclitaxel-induced neuropathic pain symptoms.

17.
EMBO Rep ; 24(8): e56538, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37377038

RESUMO

The ER regulates the spatiotemporal organization of endolysosomal systems by membrane contact. In addition to tethering via heterotypic interactions on both organelles, we present a novel ER-endosome tethering mechanism mediated by homotypic interactions. The single-pass transmembrane protein SCOTIN is detected in the membrane of the ER and endosomes. In SCOTIN-knockout (KO) cells, the ER-late endosome contacts are reduced, and the perinuclear positioning of endosomes is disturbed. The cytosolic proline-rich domain (PRD) of SCOTIN forms homotypic assemblies in vitro and is necessary for ER-endosome membrane tethering in cells. A region of 28 amino acids spanning 150-177 within the SCOTIN PRD is essential to elicit membrane tethering and endosomal dynamics, as verified by reconstitution in SCOTIN-KO cells. The assembly of SCOTIN (PRD) is sufficient to mediate membrane tethering, as purified SCOTIN (PRD), but not SCOTIN (PRDΔ150-177), brings two different liposomes closer in vitro. Using organelle-specific targeting of a chimeric PRD domain shows that only the presence on both organellar membranes enables the ER-endosome membrane contact, indicating that the assembly of SCOTIN on heterologous membranes mediates organelle tethering.


Assuntos
Retículo Endoplasmático , Membranas Intracelulares , Membranas Intracelulares/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Endossomos/metabolismo
18.
Genetics ; 224(4)2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37216205

RESUMO

Under adverse environmental conditions, nematodes arrest into dauer, an alternative developmental stage for diapause. Dauer endures unfavorable environments and interacts with host animals to access favorable environments, thus playing a critical role in survival. Here, we report that in Caenorhabditis elegans, daf-42 is essential for development into the dauer stage, as the null mutant of daf-42 exhibited a "no viable dauer" phenotype in which no viable dauers were obtained in any dauer-inducing conditions. Long-term time lapse microscopy of synchronized larvae revealed that daf-42 is involved in developmental changes from the pre-dauer L2d stage to the dauer stage. daf-42 encodes large, disordered proteins of various sizes that are expressed in and secreted from the seam cells within a narrow time window shortly before the molt into dauer stage. Transcriptome analysis showed that the transcription of genes involved in larval physiology and dauer metabolism is highly affected by the daf-42 mutation. Contrary to the notion that essential genes that control the life and death of an organism may be well conserved across diverse species, daf-42 is an evolutionarily young gene conserved only in the Caenorhabditis genus. Our study shows that dauer formation is a vital process that is controlled not only by conserved genes but also by newly emerged genes, providing important insights into evolutionary mechanisms.


Assuntos
Proteínas de Caenorhabditis elegans , Nematoides , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Nematoides/genética , Fenótipo , Perfilação da Expressão Gênica , Larva , Mutação
19.
Sensors (Basel) ; 23(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37177494

RESUMO

This paper describes a practical method for obtaining the spectra of lights emitted by a fluor in a liquid scintillator (LS) using a digital camera. The emission wavelength results obtained using a digital image were compared with those obtained using a fluorescence spectrophotometer. For general users, conventional spectrophotometers are expensive and difficult to access. Moreover, their experimental measurement setup and processes are highly complicated, and they require considerable care in handling. To overcome these limitations, a feasibility study was performed to obtain the emission spectrum through image analysis. Specifically, the emission spectrum of a fluor dissolved in a liquid scintillator was obtained using digital image analysis. An image processing method was employed to convert the light irradiated during camera exposure into wavelengths. Hue (H) and wavelength (W) are closely related. Thus, we obtained an H-W response curve in the 400~450 nm wavelength region, using a light-emitting diode. Another relevant advantage of the method described in this study is its non-invasiveness in sealed LS samples. Our results showed that this method has the potential to accurately investigate the emission wavelengths of fluor within acceptable uncertainties. We envision the use of this method to perform experiments in chemistry and physics laboratories in the future.

20.
Sensors (Basel) ; 23(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36904932

RESUMO

Neutrinos are difficult to detect because they weakly interact with matter, making their properties least known. The response of the neutrino detector depends on the optical properties of the liquid scintillator (LS). Monitoring any characteristic changes in the LS helps to understand the temporal variation of detector response. In this study, a detector filled with LS was used to study the characteristics of the neutrinos detector. We investigated a method to distinguish the concentrations of PPO and bis-MSB, which are fluors added to LS, through a photomultiplier tube (PMT) acting as an optical sensor. Conventionally, it is very challenging to discriminate the flour concentration dissolved in LS. We employed the information of pulse shape and PMT coupled with the short-pass filter. To date, no literature report on a measurement using such an experimental setup has been published. As the concentration of PPO was increased, changes in the pulse shape were observed. In addition, as the concentration of bis-MSB was increased, a decrease in the light yield was observed in the PMT equipped with the short-pass filter. This result suggests the feasibility of real-time monitoring of LS properties, which are correlated with the fluor concentration, using a PMT without extracting the LS samples from the detector during the data acquisition process.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...