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1.
Development ; 151(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38063853

RESUMEN

High-sugar diets (HSDs) often lead to obesity and type 2 diabetes, both metabolic syndromes associated with stem cell dysfunction. However, it is unclear whether excess dietary sugar affects stem cells. Here, we report that HSD impairs stem cell function in the intestine and ovaries of female Drosophila prior to the onset of insulin resistance, a hallmark of type 2 diabetes. Although 1 week of HSD leads to obesity, impaired oogenesis and altered lipid metabolism, insulin resistance does not occur. HSD increases glucose uptake by germline stem cells (GSCs) and triggers reactive oxygen species-induced JNK signaling, which reduces GSC proliferation. Removal of excess sugar from the diet reverses these HSD-induced phenomena. A similar phenomenon is found in intestinal stem cells (ISCs), except that HSD disrupts ISC maintenance and differentiation. Interestingly, tumor-like GSCs and ISCs are less responsive to HSD, which may be because of their dependence on glycolytic metabolism and high energy demand, respectively. This study suggests that excess dietary sugar induces oxidative stress and damages stem cells before insulin resistance develops, a mechanism that may also occur in higher organisms.


Asunto(s)
Células Madre Adultas , Diabetes Mellitus Tipo 2 , Proteínas de Drosophila , Resistencia a la Insulina , Animales , Femenino , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Azúcares de la Dieta/metabolismo , Células Madre Adultas/metabolismo , Células Madre Neoplásicas/metabolismo , Obesidad
2.
J Allergy Clin Immunol ; 154(2): 325-339.e3, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38494093

RESUMEN

BACKGROUND: Chronic rhinosinusitis (CRS) is a common inflammatory condition affecting the nasal and paranasal sinus mucosa, often accompanied by olfactory dysfunction. Eosinophilic CRS with nasal polyps (ECRSwNP) is a subtype of CRS characterized by eosinophilic infiltration. Animal models for ECRSwNP with olfactory dysfunction are necessary for exploring potential therapeutic strategies. OBJECTIVE: The aim of this study was to establish a mouse model of ECRSwNP combined with olfactory dysfunction in a shorter time frame using intranasal ovalbumin and Aspergillus protease (AP) administration. The efficacy of the model was validated by evaluating sinonasal inflammation, cytokine levels, olfactory function, and neuroinflammation in the olfactory bulb. METHODS: Male BALB/c mice were intranasally administered ovalbumin and AP for 6 and 12 weeks to induce ECRSwNP. The resultant ECRSwNP mouse model underwent histologic assessment, cytokine analysis of nasal lavage fluid, olfactory behavioral tests, and gene expression profiling to identify neuroinflammatory markers within the olfactory bulb. RESULTS: The developed mouse model exhibited substantial eosinophil infiltration, increased levels of inflammatory cytokines in nasal lavage fluid, and confirmed olfactory dysfunction through behavioral assays. Furthermore, olfactory bulb inflammation and reduced mature olfactory sensory neurons were observed in the model. CONCLUSION: This study successfully established a validated mouse model of ECRSwNP with olfactory dysfunction within a remarkably short span of 6 weeks, providing a valuable tool for investigating the pathogenesis and potential therapies for this condition. The model offers an efficient approach for future research in CRS with nasal polyps and olfactory dysfunction.


Asunto(s)
Modelos Animales de Enfermedad , Eosinofilia , Pólipos Nasales , Trastornos del Olfato , Rinosinusitis , Animales , Masculino , Ratones , Enfermedad Crónica , Citocinas/metabolismo , Eosinofilia/inmunología , Eosinófilos/inmunología , Eosinófilos/patología , Ratones Endogámicos BALB C , Pólipos Nasales/inmunología , Pólipos Nasales/patología , Enfermedades Neuroinflamatorias/inmunología , Enfermedades Neuroinflamatorias/patología , Enfermedades Neuroinflamatorias/etiología , Trastornos del Olfato/etiología , Trastornos del Olfato/patología , Bulbo Olfatorio/patología , Bulbo Olfatorio/inmunología , Ovalbúmina/inmunología , Rinosinusitis/inmunología , Rinosinusitis/patología
3.
Opt Express ; 31(3): 4281-4290, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36785400

RESUMEN

A tapered bus-waveguide is demonstrated to enhance the waveguide-to-cavity coupling by mass-productive, cost-effective i-line UV lithography. Through enlarging the overlap between the evanescent wave and waveguide resonator, we experimentally show that the coupling strength of silicon nitride waveguides can be 7 times stronger than the conventional coupling of a uniform, straight bus-waveguide. For the first time, strong over-coupling is identified at a 400 nm gap and quality factor ≈ 105 without elongating the coupling length. This design relieves the fabrication limits and provides the flexibility for coupling control, especially in the strongly over-coupled regime with i-line UV lithography.

4.
Environ Res ; 224: 115520, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36842698

RESUMEN

This study discussed the adsorption of mixed heavy metal ions (Cu2+, Co2+, Pb2+) and phosphate ions by ten pristine biochars and those with precipitated Mg/Al layered double hydroxide (LDH). The pristine biochars have adsorption capacities of 6.9-13.4 mg/g for Cu2+, 1.1-9.7 mg/g for Co2+, 7.8-20.7 mg/g for Pb2+, and 0.8-4.9 mg/g for PO43-. The LDH-biochars have markedly increased adsorption capacities of 20.4-25.8 mg/g for Cu2+, 8.6-15.0 mg/g for Co2+, 26.5-40.4 mg/g for Pb2+ with mixed metal ions, and 13.0-21.8 mg/g for PO43-. Part of the Mg ions but Al ions are released from the LDH-biochars during adsorption, counting less than 7.2% of the adsorbed ions. The pristine biochars have specific adsorption sites for Cu2+ and Co2+, separate Pb2+ sites related to ether groups on biochar, and areal-dependent sites for PO43-. There is no universal adsorption mechanism corresponding to mixed metal ion adsorption for individual pristine biochar involving different contributions of C-O-C, C-O-H, and CO groups and graphitic-N, pyrrolic-N, and pyridine-N groups. The LDH complexes with hydroxyl and carbonyl groups of biochar, and the LDH interacts with biochar's ether groups, which contributes to metal adsorption, against the conception that the biochar is merely a carrier of LDH as adsorbents.


Asunto(s)
Metales Pesados , Fosfatos , Agua , Plomo , Hidróxidos , Adsorción
5.
Molecules ; 28(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37513470

RESUMEN

MSN8C, an analog of mansonone E, has been identified as a novel catalytic inhibitor of human DNA topoisomerase II that induces tumor regression and differs from VP-16(etoposide). Treatment with MSN8C showed significant antiproliferative activity against eleven human tumor cell lines in vitro. It was particularly effective against the HL-60/MX2 cell line, which is resistant to Topo II poisons. The resistance factor (RF) of MSN8C for Topo II in HL-60/MX2 versus HL-60 was 1.7, much lower than that of traditional Topo II poisons. Furthermore, in light of its potent antitumor efficacy and low toxicity, as demonstrated in the A549 tumor xenograft model, MSN8C has been identified as a promising candidate for antitumor applications.


Asunto(s)
Antineoplásicos , ADN-Topoisomerasas de Tipo II , Humanos , ADN-Topoisomerasas de Tipo II/metabolismo , Inhibidores de Topoisomerasa II/farmacología , Etopósido/farmacología , Línea Celular Tumoral , Células HL-60 , Antineoplásicos/farmacología
6.
Eur Arch Otorhinolaryngol ; 279(9): 4389-4395, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35076743

RESUMEN

PURPOSE: There is no report in the literature targeting the role of Pantoea dispersa in rhinosinusitis and P. dispersa has not been identified as a commensal bacterium in the sinonasal cavity. We aimed to investigate the role of P. dispersa in rhinosinusitis. METHODS: We retrospectively reviewed the data of patients diagnosed with rhinosinusitis at a medical center in Taiwan. RESULTS: A total of 274 rhinosinusitis patients underwent sinus culture between July 2017 and July 2019. All 23 patients with acute P. dispersa rhinosinusitis experienced purulent rhinorrhea; three (13%) had nasal obstruction, but none had olfactory dysfunction, facial pressure/pain and nasal polyp. The patients with P. dispersa received a significantly shorter duration of antibiotic treatment (19.9 ± 2.6 vs. 28.9 ± 2.5 days, P = 0.015) and had lower surgery rate (0% vs. 16.7%, P = 0.043) than other patients. Patients with olfactory dysfunction were more likely to receive surgical treatment (P = 0.018). CONCLUSION: Acute rhinosinusitis caused by P. dispersa resulted in less surgical interventions and shorter treatment durations. Olfactory dysfunction may imply longer course and possibility for surgical intervention in chronic rhinosinusitis. The present study revealed that P. dispersa had the potential to colonize in human sinonasal cavities and cause rhinosinusitis.


Asunto(s)
Pólipos Nasales , Trastornos del Olfato , Rinitis , Sinusitis , Enfermedad Aguda , Enfermedad Crónica , Humanos , Pólipos Nasales/cirugía , Trastornos del Olfato/etiología , Pantoea , Estudios Retrospectivos , Rinitis/cirugía , Sinusitis/cirugía
7.
Eur Arch Otorhinolaryngol ; 279(11): 5381-5387, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35731292

RESUMEN

PURPOSE: Previous cancers can be observed in patients with nasopharyngeal carcinoma (NPC). However, whether prior cancer diagnosis affects survival outcomes remains unknown. This study aimed to explore the impact of prior cancer on the survival of patients with NPC. METHODS: We retrospectively collected data from 666 NPC patients between 2006 and 2018. The patients in this study were divided into those without prior cancer, with prior head and neck cancer, and prior non-head and neck cancer. The demographic data and survival of these groups were then analyzed. The independent prognostic factors for NPC were determined using multivariate Cox regression analysis. RESULTS: We identified 25 NPC patients with prior cancer in our case series, most of whom had a history of colorectal cancer. Patients with a history of cancer were older than those without a history of cancer (p = 0.001). In the subgroup analysis stratified by the timing of prior cancer, NPC patients with prior non-head and neck cancer within 24, 36, 60, and 120 months showed worse survival than patients without prior cancer (all p < 0.05). When stratified by cancer stage, stage III NPC patients with prior non-head and neck cancer showed worse survival than patients without prior cancer (p < 0.001). Prior cancer and diabetes can predict worse survival in patients with stage III NPC. CONCLUSION: This study demonstrated that prior cancer and diabetes are independent prognostic factors in patients with stage III NPC.


Asunto(s)
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/patología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos
8.
Molecules ; 27(17)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36080326

RESUMEN

Topo II and Hsp90 are promising targets. In this study, we first verified the structural similarities between Topo IIα ATPase and Hsp90α N-ATPase. Subsequently, 720 compounds from the Food and Drug Administration (FDA) drug library and kinase library were screened using the malachite green phosphate combination with the Topo II-mediated DNA relaxation and MTT assays. Subsequently, the antimalarial drug quinacrine was found to be a potential dual-target inhibitor of Topo II and Hsp90. Mechanistic studies showed that quinacrine could specifically bind to the Topo IIα ATPase domain and inhibit the activity of Topo IIα ATPase without impacting DNA cleavage. Furthermore, our study revealed that quinacrine could bind Hsp90 N-ATPase and inhibit Hsp90 activity. Significantly, quinacrine has broad antiproliferation activity and remains sensitive to the multidrug-resistant cell line MCF-7/ADR and the atypical drug-resistant tumor cell line HL-60/MX2. Our study identified quinacrine as a potential dual-target inhibitor of Topo II and Hsp90, depending on the ATP-binding domain, positioning it as a hit compound for further structural modification.


Asunto(s)
Antineoplásicos , Neoplasias , Adenosina Trifosfatasas/metabolismo , Antígenos de Neoplasias/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , ADN-Topoisomerasas de Tipo II/metabolismo , Reposicionamiento de Medicamentos , Proteínas HSP90 de Choque Térmico , Quinacrina/farmacología
9.
Sensors (Basel) ; 18(1)2018 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-29300315

RESUMEN

Hyperspectral imaging covering the spectral range of 384-1034 nm combined with chemometric methods was used to detect Sclerotinia sclerotiorum (SS) on oilseed rape stems by two sample sets (60 healthy and 60 infected stems for each set). Second derivative spectra and PCA loadings were used to select the optimal wavelengths. Discriminant models were built and compared to detect SS on oilseed rape stems, including partial least squares-discriminant analysis, radial basis function neural network, support vector machine and extreme learning machine. The discriminant models using full spectra and optimal wavelengths showed good performance with classification accuracies of over 80% for the calibration and prediction set. Comparing all developed models, the optimal classification accuracies of the calibration and prediction set were over 90%. The similarity of selected optimal wavelengths also indicated the feasibility of using hyperspectral imaging to detect SS on oilseed rape stems. The results indicated that hyperspectral imaging could be used as a fast, non-destructive and reliable technique to detect plant diseases on stems.


Asunto(s)
Brassica napus , Ascomicetos , Análisis de los Mínimos Cuadrados , Hojas de la Planta , Máquina de Vectores de Soporte
10.
Molecules ; 23(10)2018 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-30274227

RESUMEN

Rapid detection of Cd content in soil is beneficial to the prevention of soil heavy metal pollution. In this study, we aimed at exploring the rapid quantitative detection ability of laser- induced breakdown spectroscopy (LIBS) under the conditions of air and Ar for Cd in soil, and finding a fast and accurate method for quantitative detection of heavy metal elements in soil. Spectral intensity of Cd and system performance under air and Ar conditions were analyzed and compared. The univariate model and multivariate models of partial least-squares regression (PLSR) and least-squares support vector machine (LS-SVM) of Cd under the air and Ar conditions were built, and the LS-SVM model under the Ar condition obtained the best performance. In addition, the principle of influence of Ar on LIBS detection was investigated by analyzing the three-dimensional profile of the ablation crater. The overall results indicated that LIBS combined with LS-SVM under the Ar condition could be a useful tool for the accurate quantitative detection of Cd in soil and could provide reference for environmental monitoring.


Asunto(s)
Cadmio/análisis , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Suelo/química , Aire , Análisis de Varianza , Argón , Rayos Láser , Análisis de los Mínimos Cuadrados , Modelos Teóricos , Espectrofotometría Atómica , Máquina de Vectores de Soporte
12.
SAGE Open Med ; 12: 20503121241258736, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38895545

RESUMEN

Background: Anxiety symptoms are widely observed among the youth, and engagement in sports has been demonstrated to mitigate these symptoms. Nonetheless, the effectiveness of specific sports and the potential moderating role of psychological factors, such as self-esteem and self-efficacy, on the influence of sports on anxiety, remains to be elucidated. This study was designed to longitudinally assess the impact of sports participation on anxiety symptoms among young individuals. Methods: The study encompassed 163 university students, with a male predominance of 81.6%, and explored the influence of sport-related factors (such as mastery of table tennis skills, level and engagement) and psychological aspects (including self-efficacy, self-esteem and resilience) on anxiety symptoms, employing an 8-month longitudinal approach. Physical activity, sedentary and sleep behaviour, along with age, body mass index (BMI), and sex, were accounted for as confounding variables. Results: The study found that high table tennis performance score was found to buffer the development of anxiety symptoms in students with decreased self-esteem in an exploratory moderation model. Self-esteem and self-efficacy were negatively associated with the development of anxiety symptoms, whereas physical activity factors did not have a direct effect. Conclusion: This study highlights the potential of table tennis as a form of sport to alleviate anxiety symptoms in university students, particularly among those with decreased self-esteem. Future research should address the study's limitations and explore the potential moderating effects of other psychological factors. Overall, these findings suggest a potential new approach to treating anxiety symptoms among university students.

13.
Med Biol Eng Comput ; 61(11): 2815-2828, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37608080

RESUMEN

Gastric cancer is a common cancer endangering human life and health worldwide. Early detection and diagnosis of gastric cancer that is normally performed by flexible endoscope can significantly improve the survival rate of patients. However, current endoscopic instruments have some problems, such as limitation of degrees of freedom (DOFs) and lack of surgical triangulation. Meanwhile, the lack of an intraoperative technique for the real-time evaluation of early gastric cancer is also a serious problem. To solve these problems, we have developed a dual-bending flexible endoscopic instrument for the diagnosis and treatment of early gastric cancer. This instrument has a compact structure with a maximum outer diameter of 3 mm and an insertion length of 1220 mm. It has 5 DOFs with a dual-bending function, which can form a surgical operation triangulation to easily perform the endoscopic procedure. Apart from the surgical forceps, the end of the instrument can be equipped with different endoscopic devices to meet the needs of diagnosis and treatment, such as endomicroscopic probes, electrosurgical knives, and laser ablation optical fibers. It is verified that the instrument can carry these devices to complete corresponding tasks, demonstrating the great potential of this instrument in clinical applications.


Asunto(s)
Endoscopios , Endoscopía , Neoplasias Gástricas , Humanos , Endoscopía/instrumentación , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugía , Instrumentos Quirúrgicos
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 121932, 2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-36228486

RESUMEN

Reproducibility is still a great challenge for surface-enhanced Raman scattering (SERS), because the uncontrollable fabrication of SERS substrates or the uneven distribution of samples on the substrate result in the signal fluctuation with or between the substrates. Herein, a novel SERS quantitative method with good reproducibility was proposed. It is based on the basic principle that the SERS signal intensity is not only related to electromagnetic enhancement and the concentration of sample, but also related to the specific surface area of the substrate. The surface area information of the substrate is obtained through electrochemical technology, and then introduced into the standard curve with the linear relationship of concentration of sample and SERS intensity as a new variable to obtain a 3D standard curved surface, which effectively corrects the signal difference between the substrates, and combines the wide area Raman method to reduce the difference within the substrate, thereby improving the reproducibility of SERS quantitative detection. Using malachite green (MG) as the probe molecule and using cyclic voltammetry to calculate the substrate area fitted plane model (CV-standard curved surface), the root mean square error (RMSE) of the predicted result is 0.26 and the relative error (RE) is 0.25. It shows that the detection error significantly reduces comparing with the traditional standard curve method. Also, the proposed method can be used in other SERS quantitative detection and has potential application prospects.


Asunto(s)
Nanopartículas del Metal , Nanopartículas del Metal/química , Reproducibilidad de los Resultados , Espectrometría Raman/métodos
15.
Am J Rhinol Allergy ; 37(3): 298-306, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36426571

RESUMEN

BACKGROUND: Olfactory dysfunction is a common disease and it may be caused by sinonasal inflammation, toxin inhalation, or neurological disorders. After sinonasal inflammation, if both olfactory neuroinflammation and olfactory dysfunction occur still under investigation. OBJECTIVE: This study aimed to investigate whether neuroinflammation and olfactory dysfunction occur after lipopolysaccharide (LPS)-initiated rhinosinusitis. METHODS: Adult C57BL/6 mice were intranasally administered with LPS for 3 weeks. The olfactory function was evaluated with a buried food test. The inflammatory status of sinonasal cavity and olfactory bulb was evaluated with histology and biochemistry. RESULTS: After 3-week LPS treatment, mice developed olfactory dysfunction, sinonasal cavity, and olfactory bulb inflammation. LPS-treated mice had greater sinonasal mucosal thickness. Besides, pro-inflammatory interleukin-6, the number of goblet cells and neutrophils in the sinonasal cavity was increased after LPS administration. The olfactory sensory neurons in the olfactory epithelium and the olfactory bulb were decreased, and the olfactory function was impaired by LPS administration. Inflammatory cytokines such as interferon-γ and tumor necrosis factor-α were increased in the olfactory bulb. CONCLUSION: This study showed that LPS-initiated rhinosinusitis caused olfactory neuroinflammation and olfactory dysfunction in mice.


Asunto(s)
Trastornos del Olfato , Sinusitis , Ratones , Animales , Lipopolisacáridos , Enfermedades Neuroinflamatorias , Ratones Endogámicos C57BL , Sinusitis/patología , Inflamación/patología , Bulbo Olfatorio/patología , Trastornos del Olfato/inducido químicamente , Trastornos del Olfato/patología
16.
J Biophotonics ; 16(3): e202200265, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36323629

RESUMEN

To distinguish between children with autism spectrum disorder (ASD) and typically developing (TD) children, we have uncovered a new discriminative feature, hemoglobin coupling. Functional near-infrared spectroscopy (fNIRS) was used to record resting-state hemodynamic fluctuations in the bilateral temporal lobes in 25 children with ASD and 22 TD children, in which the coupling between low frequency oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (Hb) fluctuations was evaluated by Pearson correlation coefficient. The results showed significantly weak coupling in children with ASD in both the left and right, and throughout the whole temporal cortex. To explain this observation, a simulation study was performed using a balloon model, in which we found four related parameters could impact the coupling. This study suggested that hemoglobin coupling might be applied as a new cerebral hemodynamic characteristic for ASD screening or diagnostics.


Asunto(s)
Trastorno del Espectro Autista , Niño , Femenino , Humanos , Masculino , Trastorno del Espectro Autista/sangre , Encéfalo/metabolismo , Hemoglobinas/análisis , Oxihemoglobinas/análisis , Espectroscopía Infrarroja Corta
17.
Chem Commun (Camb) ; 59(64): 9778-9779, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37497731

RESUMEN

Correction for 'Catalytically active designer crown-jewel Pd-based nanostructures encapsulated in metal-organic frameworks' by Liyu Chen et al., Chem. Commun., 2017, 53, 1184-1187, https://doi.org/10.1039/C6CC09270E.

18.
Bioresour Technol ; 367: 128303, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36368488

RESUMEN

Biochar is an eco-friendly, low-cost, and carbon-rich material. This study synthesized the biochars from three agricultural wastes, pinecone, white popinac, and sugarcane bagasse, and then modified them by manganese ferrite (MnFe2O4) co-precipitation. These biochars were applied as adsorbents for the removal of Cu(II) ions from water. All three different MnFe2O4-biochars have similar adsorption performances: rapid adsorption kinetics with equilibrium being reached within 5 hr of contact and significantly enhanced adsorption capacities of Cu(II) ions from water. The principal adsorption mechanisms were identified as complexation reactions, contributed by the carboxyl and hydroxyl groups by pristine biochars and by the Mn-O and Fe-O groups for all three MnFe2O4-biochars. The MnFe2O4-biochars can be reused for three cycles, with the maximum adsorption capacities of Cu(II) of the regenerated biochars declining with the loss of precipitated MnFe2O4.


Asunto(s)
Saccharum , Contaminantes Químicos del Agua , Adsorción , Cobre , Celulosa , Carbón Orgánico , Iones , Cinética , Agua
19.
Life (Basel) ; 13(5)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37240782

RESUMEN

Ascorbic acid (AA) is an indispensable nutrient required to sustain optimal poultry health and performance, which is commonly excluded from the diet of broilers. To investigate the synthesis and distribution of AA during broiler growth and clarify its possible turnover, 144 1 d old healthy Arbor Acres broilers with a body weight of approximately 41 g were randomly assigned to eight groups of 18 broilers each. The kidney, liver, ileum, and spleen of one bird from each group were collected every week until 42 d to detect the synthesis capacity, tissue distribution, and transporter gene expression of AA. The results showed that kidney L-gulonolactone oxidase (GLO) activity responded quadratically (p < 0.001), with maximum activity observed at 7 to 21 d old. Hepatic total AA and dehydroascrobate (DHA) concentration increased linearly (p < 0.001) with age, as did splenic total AA (p < 0.001). In the ileum, mRNA expression of sodium vitamin C transporter 1/2 (SVCT1/2) decreased with the growing age of the broilers (p < 0.05). The expression of SVCT1 in the kidney was not influenced by the growing age of the broilers. The progressive buildup of AA in the liver and spleen of broilers as they age implies an amplified demand for this nutrient. The waning synthesis capacity over time, however, raises concerns regarding the possible inadequacy of AA in the latter growth phase of broilers. The addition of AA to the broilers' diet might have the potential to optimize their performance. However, the effectiveness of such dietary supplementation requires further investigation.

20.
Sci Rep ; 13(1): 13211, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37580361

RESUMEN

We demonstrate the engineering of waveguide dispersion by lithographically patterning the polymer cladding on silicon nitride waveguide resonators. Both normal and anomalous dispersion, ranging from - 462 to 409 ps/nm/km, can be achieved for the same waveguide dimension within an integrated photonic chip. In the meantime, this simple process shows no impact on the waveguide loss and the quality factor of the waveguide resonators, offering flexibility in tailoring designable dispersion for a universal photonic platform. In addition, by adjusting the coverage ratio of cladding, relatively low dispersion (≈ - 130 ps/nm/km) is also demonstrated in the same waveguide resonator, yielding the potentials for zero-dispersive waveguide resonators by a proper coverage ratio of the polymer cladding.

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