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1.
Photochem Photobiol ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634423

RESUMEN

Excessive exposure to blue light can cause retinal damage. Hydrogen-rich saline (HRS), one of the hydrogen therapies, has been demonstrated to be effective in eye photodamage, but the effect on the expression of melanopsin in intrinsically photosensitive retinal ganglion cells (ipRGCs) is unknown. In this study, we used a rat model of light-induced retinal injury to observe the expression of melanopsin after HRS treatment and to determine the effect of HRS on retinal ganglion cell protection. Adult SD rats were exposed to blue light (48 h) and treated with HRS for 0, 3, 7, and 14 days. Real-time polymerase chain reaction (qRT-PCR) and Western blotting (WB) were performed to find the expression of genes and proteins, respectively. The function of retinal ipRGCs was measured by pattern-evoked electroretinography (pERG). The number and morphological changes of melanopsin-positive ganglion cells in the retina were observed by immunofluorescence (IF). Acute blue light exposure caused a decrease in ipRGC function, decreased expression of melanopsin protein and the melanopsin-positive RGCs, and diminished immunoreactivity in dendrites. However, over time, melanopsin showed a tendency to self-recovery, with an increase in melanopsin protein expression and the number of melanopsin-positive RGCs, with incomplete recovery of function within two weeks. HRS treatment accelerated the recovery process, with a significant increase in melanopsin expression and the number of melanopsin-positive RGCs, and an improvement in the pERG waveform within two weeks.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38530452

RESUMEN

PURPOSE: To investigate the alterations in extraocular muscles (EOMs) by magnetic resonance imaging (MRI) among patients diagnosed with Duane retraction yndrome (DRS) and congenital fibrosis of the extraocular muscles (CFEOM), who present with various cranial nerve anomalies in an attempt to enhance the clinical diagnostic process. METHODS: A case-control study was conducted to evaluate 27 patients with DRS and 14 patients with CFEOM. All patients underwent MRI scans of the brainstem and orbital examination. Neurodevelopmental assessments were conducted through MRI, and maximum cross-sectional area and volumes of EOMs were obtained. Three types of models were constructed using machine learning decision tree algorithms based on EOMs to predict disease diagnosis, cranial nerve abnormalities, and clinical subtypes. RESULTS: Patients with bilateral CN VI abnormalities had smaller volumes of LR, MR, and IR muscles compared to those with unilateral involvement (P < 0.05). Similarly, patients with CFEOM and unilateral third cranial nerve abnormalities had a smaller maximum cross-section of the affected eye's SR compared to the contralateral eye (P < 0.05). In patients with both CN III and CN VI abnormalities, the volume of SR was smaller than in patients with CN III abnormalities alone (P < 0.05). The prediction model using EOMs volume showed a diagnostic precision of 82.5% for clinical cases and 60.1% for predicting cranial nerve abnormalities. Nonetheless, the precision for identifying clinical subtypes was relatively modest, at only 41.7%. CONCLUSION: The distinctive volumetric alterations in EOMs among individuals exhibiting distinct cranial nerve anomalies associated with DRS or CFEOM provide valuable diagnostic insights into to Congenital Cranial Neurodevelopmental Disorders (CCDDs). MRI analysis of EOMs should thus be regarded as a crucial diagnostic modality.

3.
Exp Eye Res ; 235: 109619, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37633324

RESUMEN

PURPOSE: To investigate the impact of different duration of blue light exposure on ocular parameters and choroidal blood perfusion in guinea pigs with lens-induced myopia. METHOD: Three-week-old Guinea pigs were randomly assigned to different light-environment groups. All groups were subjected to 12-h light/dark cycle. The control (NC) group was conditioned without intervention. While lens-induced myopia (LIM) groups had a -10D lens placed in the right eye and 0D in the left eye. The guinea pigs were exposed to increasing periods of blue-light (420 nm) environment for 3,6,9,12 h per day. Changes in refraction, axial length (AL), the radius of corneal curvature (CCR), choroidal thickness (ChT), and choroidal blood perfusion (ChBP)were measured in both LIM-eye and fellow-eye during the second and fourth week of LIM duration. RESULTS: During the first two weeks of the experiment, blue light exposure raised ChBP and ChT, and the effect of suppressing myopia was proportional to the duration of blue light exposure. However, in the fourth week of the experiment, prolonged blue light (12BL) exposure led to a reduction in retinal thickness and the increase in ChT and ChBP ceased. Shorter blue light exposure had a better effect on myopia suppression, with all blue light groups statistically different from the LIM group. CONCLUSION: Exposure to blue-light appears to have the potential to improve ChBP and ChT, thereby inhibiting the development of myopia. we speculate that blue-light inhibits the development of myopia for reasons other than longitudinal chromatic aberration (LCA). However,long-term exposure to blue-light may have adverse effects on ocular development. The next step is to investigate in depth the mechanisms by which the rational use of blue light regulates choroidal blood flow, offering new hope for the treatment of myopia.


Asunto(s)
Miopía , Animales , Cobayas , Coroides , Modelos Animales de Enfermedad , Luz , Miopía/etiología , Perfusión , Refracción Ocular
4.
Exp Ther Med ; 26(3): 442, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37614419

RESUMEN

The present prospective study aimed to investigate the structural and functional changes in patients with concomitant exotropia using multimodal MRI. A total of 11 adult patients with concomitant exotropia (5 males and 6 females) and 11 healthy adult individuals (5 males and 6 females) were recruited and examined using multimodal MRI techniques. Near and distance exotropia deviation angles were measured. The structrual changes were evaluated using the gray matter volume. Functional reorganization was assessed using the amplitude of low-frequency fluctuation, regional homogeneity and resting-state functional connectivity (FC) on MRI. No significant differences could be found in terms of sex, age or body mass index between the two groups. However, the near and distance exotropia angles were significantly higer in the concomitant exotropia group compared with those in the normal control group (P<0.001). Compared with those in normal individuals, the bilateral thalamus, right middle temporal gyrus (MTG) and right cuneus had significantly reduced gray matter volumes in the concomitant exotropia group (false discovery rate corrected, P<0.05). Reduced FC was found between the bilateral thalamus and the bilateral precuneus, between the right MTG and the right medial superior frontal gyrus in addition to the right precuneus, and between the right cuneus and the right primary sensorimotor cortex (P<0.05, Gaussian random-field corrected) in the concomitant exotropia group compared with that in the normal individuals. In conclusion, the present study indicated that structural and functional reorganization occurs in specific brain regions of patients with concomitant exotropia. These reorganized areas appeared to mainly involve the subcortical structures and related cortices that process visual information.

5.
Micromachines (Basel) ; 14(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36677147

RESUMEN

In this paper, a D-band direct conversion IQ receiver with on-chip multiplier chain is presented. The D-band LNA with gain-boosting and stagger-tunning technique is implemented to provide high gain and large bandwidth. X9 multiplier chain including Marchand balun and quadrature (90°) hybrid is employed to provide four path LO signal to drive IQ mixer. This receiver is implemented in a 130nm SiGe process and consumes a core area of 1.04 mm2. From the experimental results, the proposed receiver exhibits a 20 GHz bandwidth from 150 GHz to 170 GHz, with CG of 28 dB and NF of 7.3 dB at 158 GHz.

6.
ACS Omega ; 5(15): 8831-8838, 2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32337445

RESUMEN

The sintering process of bone china bodies containing 0, 2, 4, and 6 wt % palygorskite was studied by X-ray diffraction (XRD), differential scanning calorimetry and thermogravimetry (DSC/TG), and dilatometric tests. According to the XRD and DSC/TG results, the increment of palygorskite increased the content of the amorphous phase and reduced the formation temperature of the early liquid phase in the bone china bodies. The shrinkage data showed that the starting sintering temperature and maximum shrinkage temperature of bone china bodies in the stage of liquid-phase sintering decreased by 20 and 15 °C via adding 6 wt % palygorskite, respectively. Also, the maximum shrinkage rose with increasing amount of palygorskite. Moreover, the kinetic analysis of shrinkage data was conducted by the Salem model. The value of the mechanism-characteristic exponent, m, rose from 0.62 to 0.91 by adding 6 wt % palygorskite. In addition, with increasing palygorskite, the value of activation energy, E a, linearly reduced, and the value of rate constant A increased.

7.
Sci Rep ; 9(1): 7337, 2019 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-31089210

RESUMEN

In this paper, a new type of porous ceramics was prepared using the raw sepiolite mineral. The porous ceramics was shaped by the dry pressing method and sintered in the range of 700 ~ 1200 °C. The temperature-microstructure evolution and the properties of porous sepiolite ceramics were investigated by thermo gravimetric and differential thermal analyses (TG-DTA), X-ray diffraction (XRD), bending strength, compressive strength, scanning electron microscopy (SEM) and mercury intrusion porosimeter (MIP). The sintering kinetics of the porous ceramics from sepiolite was investigated by means of stepwise isothermal dilatometry (SID). The mechanical properties improved with the increasing sintering temperature, and the bending strength and compression strength reached a maximum of 52 MPa and 32 MPa respectively at 1200 °C. The porosity increased with the sintering temperature until 1100 °C attaining the value of 55.40% and then decreased to a value of 46.48% at 1200 °C. The main crystal phases of the porous ceramics were akermanite and diopside. At 1200 °C, the pores inside the ceramics basically follows a unimodal distribution, which was mainly located near 553 nm. The sintering activation energy of porous sepiolite ceramics was measured by step isothermal thermal expansion with a value of 791.42 kJ/mol in the range of 1000 °C to 1200 °C.

8.
R Soc Open Sci ; 5(10): 180483, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30473813

RESUMEN

The work investigated the effect of sepiolite nanofibres on mechanical properties and sintering behaviour of shellfish porcelain. Samples of shellfish porcelain reinforced by sepiolite nanofibres were fired in an electric furnace at 1150, 1200 and 1250°C for a period of 80, 100, 120 and 140 min. Sintered samples were characterized by flexural strength, fracture toughness, scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The results showed that 2 wt% sepiolite nanofibres could increase the flexural strength and fracture toughness of the porcelain bodies through the fibre pullout and the weak interface mechanisms. Sintering activation energies were determined according to the linear shrinkage results. It is found that the liquid-phase sintering mechanism of shellfish porcelain with sepiolite nanofibres is a diffusion mechanism. Porcelain without sepiolite is controlled by volume diffusion, and eventually, the grain boundary diffusion began to appear with the increase of sepiolite addition.

9.
Wei Sheng Yan Jiu ; 45(2): 263-7, 2016 Mar.
Artículo en Chino | MEDLINE | ID: mdl-27301227

RESUMEN

OBJECTIVE: To investigate the toxicity of linear alkylbenzene sulfonate (LAS) on human Chang liver cells. METHODS: Chang liver cells were cultured in complete growth medium, RPMI 1640 supplemented with 10% fetal calf serum and divided into control group (cultured with normal medium without LAS), LAS low, medium, high groups (37.57, 75.0 and 150.0 mg/L). After being incubated for 24 h, morphological changes were observed under inverted microscope. The proliferation rate was measured by MTT assay. The injury of cells was evaluated through levels of malondialdehyde (MDA) lactate dehydrogenase (LDH) and aspartate amine transfer (AST). Apoptosis and necrosis of Chang liver cells were explored using Hoechst 33342 and PI staining. RESULTS: When Chang liver cells were treated with different concentrations of LAS, morphological changes of cells were shown that there were black grains in the surface, the number of cells decreased, cast-off cells and cell breakage increased and there were large numbers of necrotic cells in higher-dose groups. Compared with the control group, the cell proliferation was inhibited, the levels of MDA, LDH and GOT increased and the rates of apoptosis and necrosis enhanced significantly because of the treatment of LAS. CONCLUSION: LAS can injure Chang liver cells in a way, it can inhibit cell proliferation and induce cells apoptosis.


Asunto(s)
Ácidos Alcanesulfónicos/toxicidad , Apoptosis , Proliferación Celular , Hepatocitos/efectos de los fármacos , Aspartato Aminotransferasas/metabolismo , Células Cultivadas , Humanos , L-Lactato Deshidrogenasa/metabolismo , Malondialdehído/metabolismo
10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 40(6): 585-91, 2015 Jun.
Artículo en Chino | MEDLINE | ID: mdl-26164505

RESUMEN

BACKGROUND: To observe the effect of linear alkylbenzenesulfonate (LAS) on oxidative stress and collagen fiber in skin tissue of mice and to explore the correlation between oxidative stress and collagen metabolism.
 METHODS: Forty healthy Kunming mice (male) were randomly divided into 4 groups: a control group, a low-, middle- and high-dose group of LAS (LD, MD and HD groups), treated with LAS at 150, 300 and 600 mg/L respectively (n=10 per group). The skin on the back of mice was smeared with distilled water or different dosage of LAS for 60 days. The measured indexes included general condition of mice, HE and Masson staining of skin, the content of hydroxyproline (Hyp) in skin tissue, the activity of super oxidase dismutase (SOD) and the content of malondialdehyde (MDA) in skin tissue and serum, and the activity of lactate dehydrogenase (LDH) in serum.
 RESULTS: Compared with the control group, the changes of diet, daily activities and mental state of mice with different dose of LAS were not obvious during the experiment, but the body weight of mice in the experimental groups reduced obviously after 4 weeks of experiment (P<0.01), and their skin tissue was thinner, some of epidermis of skin contained areas with cellular necrosis and abscission. Superficial layer of dermis was infiltrated by inflammatory cells. The collagen fibers were looser and dimmer. At the same time, the content of MDA and the activity of LDH increased remarkably (P<0.01), while the activity of SOD and the content of Hyp decreased obviously (P<0.01).
 CONCLUSIONS: LAS can induce oxidative stress in the skin tissue of mice, which can destroy the integrity of skin structure and collagen fiber and reduce the content of collagen fiber. The oxidative damage might be the primary cause for disorders of collagen fiber.
.


Asunto(s)
Ácidos Alcanesulfónicos/farmacología , Colágeno/metabolismo , Estrés Oxidativo , Piel/efectos de los fármacos , Animales , Masculino , Malondialdehído/metabolismo , Ratones , Piel/metabolismo
11.
Int J Colorectal Dis ; 30(9): 1209-16, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26077668

RESUMEN

OBJECTIVE: The objectives of this paper were to establish a model for the conversion of laparoscopic rectal resection to open surgery and to predict possible conversion before surgery. METHODS: The clinical data of 602 cases of laparoscopic rectal resection were retrospectively assessed. Risk factors associated with conversion of laparoscopic rectal resection to open rectal surgery were identified by logistic regression analysis. Also, a scoring system was created to calculate a score for the conversion of laparoscopic rectal resection to predict possible conversion for patients who underwent laparoscopic rectal resection before surgery. RESULTS: A total of 90 patients required conversion (total conversion rate = 14.95%). The established model included six variables: male gender, surgical experience (≤25 cases), history of abdominal surgery, body mass index ≥ 28, tumor diameter ≥ 6 cm, and tumor invasion or metastasis, for which 6, 4, 5, 10, 15, and 21 points were assigned, respectively. A patient with a total score >14.5 points was considered to have a high probability of conversion, whereas a patient with a total score <14.5 points was considered at a low risk. CONCLUSION: Preoperative determination of conversion score may predict possible conversion of laparoscopic rectal resection and thus reduce unnecessary open rectal surgery.


Asunto(s)
Conversión a Cirugía Abierta/estadística & datos numéricos , Laparoscopía/efectos adversos , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Abdomen/cirugía , Anciano , Índice de Masa Corporal , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica , Metástasis de la Neoplasia , Periodo Preoperatorio , Probabilidad , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Carga Tumoral
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