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1.
Cortex ; 174: 241-255, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38582629

RESUMO

Shape is a property that could be perceived by vision and touch, and is classically considered to be supramodal. While there is mounting evidence for the shared cognitive and neural representation space between visual and tactile shape, previous research tended to rely on dissimilarity structures between objects and had not examined the detailed properties of shape representation in the absence of vision. To address this gap, we conducted three explicit object shape knowledge production experiments with congenitally blind and sighted participants, who were asked to produce verbal features, 3D clay models, and 2D drawings of familiar objects with varying levels of tactile exposure, including tools, large nonmanipulable objects, and animals. We found that the absence of visual experience (i.e., in the blind group) led to stronger differences in animals than in tools and large objects, suggesting that direct tactile experience of objects is essential for shape representation when vision is unavailable. For tools with rich tactile/manipulation experiences, the blind produced overall good shapes comparable to the sighted, yet also showed intriguing differences. The blind group had more variations and a systematic bias in the geometric property of tools (making them stubbier than the sighted), indicating that visual experience contributes to aligning internal representations and calibrating overall object configurations, at least for tools. Taken together, the object shape representation reflects the intricate orchestration of vision, touch and language.


Assuntos
Cegueira , Percepção do Tato , Humanos , Cegueira/psicologia , Visão Ocular , Tato
2.
Chemosphere ; 350: 141004, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141682

RESUMO

Polychlorinated naphthalenes (PCNs) were characterized as persistent organic pollutants (POPs) that were widely distributed in the environment. Although the striking in vivo toxicity of these pollutants towards both animals and humans was well documented, their cytotoxicity and mechanism of action have not been extensively investigated. In this study, the in vitro antiproliferative activity of mono- and di-chloronaphthalenes as representative PCNs were evaluated and the results indicated strong growth inhibitory effects against mammalian cells, especially the human breast MCF-10A cell and human hepatic HL-7702 cells. 2-Chloronaphthalene with the most potent antiproliferative effects within the tested PCNs, which showed IC50 values ranging from 0.3 mM to 1.5 mM against selected human cell lines, was investigated for its working mechanisms. It promoted cellular apoptosis of MCF-10A cells upon the concentration of 200 µM. It also induced the autophagy of MCF-10A cells in a dose-dependent manner, resulting in cell death via the interaction of autophagy and apoptosis. Thus, these findings supported the theoretical foundation for interventional treatment of PCNs toxicity and also provided implications for the use of chemopreventive agents against the toxic chlorinated naphthalenes in the environments.


Assuntos
Poluentes Ambientais , Animais , Humanos , Poluentes Ambientais/análise , Fígado/química , Naftalenos/toxicidade , Naftalenos/análise , Apoptose , Mamíferos
3.
Artigo em Inglês | MEDLINE | ID: mdl-36165520

RESUMO

BACKGROUND: Cancer is a malignant disease that causes millions of deaths each year worldwide. As one of the cancer therapeutic strategies, chemotherapy is a means to destroy rapidly dividing cells. The main problem with cancer chemotherapy is the lack of selectivity of conventional chemotherapeutic drugs, leading to toxicity towards normal cells. Therefore, the discovery of anticancer agents with selectivity for fast-growing cancer cells was desirable. OBJECTIVE: In this study, we report the synthesis and identification of the novel 5-benzyl juglone as a potential anticancer agent with selectivity toward certain cancer cell lines. METHODS: An efficient synthetic method for 5-benzyl juglone has been established. The proliferation of cancer cell lines and a normal cell line treated by the target compound were studied using an MTT assay. In addition, the cell cycle arrest and apoptosis were determined by flow cytometry. RESULTS: Based on the Diels-Alder (D-A) reaction between 3,6-dimethoxy benzyne intermediate with furan, further acid-catalyzed intramolecular rearrangement and CAN-mediated oxidation, a convenient synthesis of 5-benzyl juglone has been achieved with high overall yield. The results from in vitro biological evaluation indicated that the juglone derivative exhibited potent antiproliferative activity against HCT-15 human colorectal cancer cells with an IC50 value of 12.27 µM. It exerted high inhibitory activity toward MCF-7 human breast cancer cells and, to a much lesser extent, to corresponding MCF-10A human breast epithelial normal cells with the IC50 ratio (IC50 in MCF-7 divided by IC50 in MCF-10A) of 0.62. CONCLUSION: The mechanistic investigations indicated that 5-benzyl juglone could induce cell cycle arrest at the G0/G1 phase and promote apoptosis of HCT-15 cells. The apoptotic effects possibly also contributed to its higher selectivity toward cancer cells than normal cell lines.

4.
Appl Opt ; 58(6): 1537-1546, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30874044

RESUMO

L625 4-wavelength dual Raman-Mie lidar was used to detect elastically Mie backscattered light at emitting wavelengths (532 and 355 nm) emitted by one Nd:YAG laser, and the nitrogen Raman light (607 and 386 nm) inelastically backscattered by nitrogen molecules at Hefei (117.3°E, 31.9°N), China from 2007 to 2013. From the four return signal profiles, highly accurate aerosol extinction and backscatter coefficients, lidar ratio, Ångström exponent, and aerosol Junge exponent can be determined. Furthermore, with a priori assumption of the real part of complex refractive index nr=1.50, the profiles of more aerosol microphysical parameters can be retrieved with their respective errors in the free troposphere, such as the imaginary part of the refractive index, Junge number density coefficient, and particle mass index. The profiles of aerosol microphysical parameters were obtained for 179 nights. Their variation and statistical features were discussed.

5.
Biotechnol Appl Biochem ; 66(1): 82-90, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30311952

RESUMO

MicroRNAs (miRNAs) diagnostics can be useful for diagnosing or confirming miRNA abundance and are used in screening tests and to assess changes in miRNAs in vivo. At present, the use of traditional nucleic acid amplification assays to detect miRNAs has been limited in laboratory environment because of the time, equipment, and technical expertise required to perform these assays. A specialized, rapid affordable miRNA detection system is necessary when there are limited resources or point-of-care testing needs. We designed a portable and affordable fluorescence-based miRNA detection system based on isothermal signal amplification technology, using SYBR Green II as a fluorescent dye. To reduce costs, we chose LED as a light source and designed the corresponding optical path for LED. The portable detection system shows results consistent with those by real-time PCR, and can be used to detect miR-183 with a limit of detection of approximately 2 fmol. We used the system to detect miR-183 in tissues and blood from patients with hepatocellular carcinoma (HCC). The results from the portable detection device were compared with those from clinical trials and indicated that the miR-183 fluorescence signal could successfully identify HCC and provide information related to cancer progression.


Assuntos
Carcinoma Hepatocelular , Fluorescência , Neoplasias Hepáticas , MicroRNAs , Compostos Orgânicos/química , RNA Neoplásico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , RNA Neoplásico/genética , RNA Neoplásico/metabolismo
6.
Clin Exp Hypertens ; 36(5): 321-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24047449

RESUMO

OBJECTIVES: This study documented the prevalence and clinical features of white coat hypertension (WCH) among Chinese Han patients with type 2 diabetes mellitus (T2DM). METHODS: Clinic and ambulatory blood pressure (BP) measurements were compared in 856 patients with T2DM to determine the frequency of WCH (WCH was defined as clinical blood pressure ≥140/90 mmHg and daytime blood pressure <135/85 mmHg and/or 24-h ambulatory BP (ABP) mean value of <130/80 mmHg on ambulatory BP monitoring (ABPM). Weight, waist circumference (WC), body mass index (BMI), waist to height ratio (WHtR), fasting blood glucose, glycosylated hemoglobin level and circadian BP patterns were also measured to find clinical features predictive of WCH in T2DM. RESULTS: The prevalence of WCH was 7.36% (63/856) in the overall population, 6.13% (29/473) in male and 8.88% (34/383) in female (p < 0.05). WCH accounted for 14.03% (63/449) of diagnosed hypertension. Age, course of T2DM, male WC were independent protective factors, whereas female sex, smoking and alcohol consumption were independent risk factors for WCH in T2DM. Non-dippers and reverse dippers made up larger proportion of the WCH group (p < 0.01). CONCLUSION: WCH is relatively common among T2DM patients, it is a unique condition distinct from essential hypertension (EH), and WCH patients also exhibit significant differences in clinical parameters.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Hipertensão do Jaleco Branco/epidemiologia , Adulto , Povo Asiático , Determinação da Pressão Arterial/métodos , Monitorização Ambulatorial da Pressão Arterial , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Hipertensão Essencial , Feminino , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Hipertensão do Jaleco Branco/complicações , Hipertensão do Jaleco Branco/diagnóstico
7.
J Diabetes Complications ; 27(1): 82-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22906551

RESUMO

OBJECTIVE: The prevalence and clinical features of masked hypertension (MH) in type 2 diabetes mellitus patients (T(2)DM) were investigated to define clinical indices which may aid diagnosis and treatment. METHODS: Clinical blood pressure (CBP) and ambulatory blood pressure (ABP) were measured in 856 T(2)DM patients to differentiate normotensive (NT), essential hypertensive (EH), and MH. Waist circumference (WC), abdominal circumference (AC), body mass index (BMI), waist to height ratio (WHtR), fasting blood glucose (FBG), and glycated hemoglobin levels were measured and compared between BP groups. RESULTS: In total, 359 patients had normal CBP, of which 13.37% were diagnosed with MH based on established criteria. Males had significantly higher rates of MH (15.30%) than females (11.36%) (P=0.036). The MH detection rate increased with age and T(2)DM duration. There were no significant differences in BMI, WC or WHtR between total MH and EH groups. MH females, however, had lower BMIs than female EH females (P=0.023). Smoking, alcohol, and familial EH history were lower in MH than EH patients (smoking, P=0.029; alcohol ,P=0.001; and EH history, P=0.000), while BMI (male, P=0.037, female, P=0.015), WC (male, P=0.012, female, P=0.021), WHtR (P=0.011), smoking (P=0.016), and alcohol consumption (P=0.000) were higher in MH than NT patients. BMI, WHtR, 6-15 year disease course of diabetes, smoking and alcoholism were independent risk factors of T(2)DM complicated with MH. The dipper BP circadian pattern was significantly lower in MH than NT patients (P=0.001). The non-dipper pattern was lower in MH than EH (P=0.018) but higher than in NT (P=0.000). CONCLUSIONS: A significant fraction of T(2)DM patients were diagnosed with MH. Clinical presentation also contrasted sharply from EH, MH is a specific blood pressure status that may severely damage target organs in T(2)DM.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Hipertensão Mascarada/epidemiologia , Adulto , Fatores Etários , Idoso , Pressão Sanguínea/fisiologia , Monitorização Ambulatorial da Pressão Arterial , Ritmo Circadiano/fisiologia , Diabetes Mellitus Tipo 2/complicações , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Hipertensão Mascarada/diagnóstico , Hipertensão Mascarada/etiologia , Pessoa de Meia-Idade , Prevalência
8.
Artigo em Chinês | MEDLINE | ID: mdl-22493892

RESUMO

OBJECTIVE: To investigate the effect of hyperbaric oxygen (HBO) treatment on the expression of nitric oxide synthase (NOS) mRNA in cortex after acute traumatic cerebral injury, and to study the mechanism of HBO on brain injury. METHODS: Acute traumatic brain injury model was established with rest received free fall injury method in SD rats. 0.25 MPa HBO treatment was used 1 h or 12 h after brain injury and the cortex was isolated 6 h or 24 h after brain injury respectively. The expression of mRNA coding for nNOS, eNOS or iNOS were assayed using reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The expression of nNOS, eNOS and iNOS mRNA were significantly decreased in 0.25 MPa HBO treatment groups than those in acute cerebral injury groups (P < 0.01). The amount of nNOS, eNOS and iNOS mRNA was significantly lower in HBOT 24 h group than those in HBOT 6 h group (P < 0.05, P < 0.01). There was no significantly difference among nNOS, eNOS and iNOS mRNA in 0.25 MPa normoxic hyperbaric nitrogen groups and acute cerebral injury groups (P > 0.05). CONCLUSION: HBO may exert significant effects on the expression of nNOS mRNA/iNOS mRNA and protect cortical neuronal from traumatic cerebral injury.


Assuntos
Lesões Encefálicas/metabolismo , Lesões Encefálicas/terapia , Oxigenoterapia Hiperbárica , Óxido Nítrico Sintase/metabolismo , Animais , Feminino , Masculino , Óxido Nítrico Sintase/genética , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley
9.
Phys Rev Lett ; 69(22): 3212-3215, 1992 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-10046759
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