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1.
Clin Ophthalmol ; 17: 3443-3451, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026590

RESUMO

Aim: The objective of this study was to examine changes in functional connectivity (FC) in the hippocampus among patients with high myopia (HM) compared to healthy controls (HCs) through the utilization of seed-based functional connectivity (FC) analysis. Methods: Resting-state functional magnetic resonance imaging (fMRI) was conducted on a sample of 82 patients diagnosed with high myopia (HM) and 59 HCs. The two groups were matched based on age, weight and other relevant variables. Using seed-based FC analysis to detect alterations in hippocampal FC patterns in HM patients and HCs. Furthermore, a correlation analysis was performed to examine the associations between the mean functional connectivity (FC) signals in various brain regions of patients with HM and their corresponding clinical manifestations. Results: The FC values in the left temporal pole-temporal gyrus (L-TPOsup), right hippocampus (R-HIP), left medial temporal gyrus (L-MTG) and left hippocampus in HM patients were significantly lower than those of healthy subjects. In the left temporal pole-superior temporal gyrus (L-TPOsup), right orbital part of middle frontal gyrus (RO-MFG), left fusiform gyrus (L-FG), left cerebellum superior (L-Cbe6), left middle temporal gyrus (L-MTG), right thalamus (R-THA), and right hippocampus, FC values were also significantly lower. Conclusion: Brain dysfunction was observed in various regions of the HM patients, suggesting the existence of neurobiological alterations that could lead to impairments in visual cognition, movement, emotional processing, and visual memory.

2.
Front Neurosci ; 17: 1227081, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547140

RESUMO

Background: There is increasing evidence that patients with retinal detachment (RD) have aberrant brain activity. However, neuroimaging investigations remain focused on static changes in brain activity among RD patients. There is limited knowledge regarding the characteristics of dynamic brain activity in RD patients. Aim: This study evaluated changes in dynamic brain activity among RD patients, using a dynamic amplitude of low-frequency fluctuation (dALFF), k-means clustering method and support vector machine (SVM) classification approach. Methods: We investigated inter-group disparities of dALFF indices under three different time window sizes using resting-state functional magnetic resonance imaging (rs-fMRI) data from 23 RD patients and 24 demographically matched healthy controls (HCs). The k-means clustering method was performed to analyze specific dALFF states and related temporal properties. Additionally, we selected altered dALFF values under three distinct conditions as classification features for distinguishing RD patients from HCs using an SVM classifier. Results: RD patients exhibited dynamic changes in local intrinsic indicators of brain activity. Compared with HCs, RD patients displayed increased dALFF in the bilateral middle frontal gyrus, left putamen (Putamen_L), left superior occipital gyrus (Occipital_Sup_L), left middle occipital gyrus (Occipital_Mid_L), right calcarine (Calcarine_R), right middle temporal gyrus (Temporal_Mid_R), and right inferior frontal gyrus (Frontal_Inf_Tri_R). Additionally, RD patients showed significantly decreased dALFF values in the right superior parietal gyrus (Parietal_Sup_R) and right paracentral lobule (Paracentral_Lobule_R) [two-tailed, voxel-level p < 0.05, Gaussian random field (GRF) correction, cluster-level p < 0.05]. For dALFF, we derived 3 or 4 states of ALFF that occurred repeatedly. There were differences in state distribution and state properties between RD and HC groups. The number of transitions between the dALFF states was higher in the RD group than in the HC group. Based on dALFF values in various brain regions, the overall accuracies of SVM classification were 97.87, 100, and 93.62% under three different time windows; area under the curve values were 0.99, 1.00, and 0.95, respectively. No correlation was found between hamilton anxiety (HAMA) scores and regional dALFF. Conclusion: Our findings offer important insights concerning the neuropathology that underlies RD and provide robust evidence that dALFF, a local indicator of brain activity, may be useful for clinical diagnosis.

3.
Front Neurosci ; 17: 1126262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816124

RESUMO

Aim: This study was conducted to explore differences in static functional connectivity (sFC) and dynamic functional connectivity (dFC) alteration patterns in the primary visual area (V1) among high myopia (HM) patients and healthy controls (HCs) via seed-based functional connectivity (FC) analysis. Methods: Resting-state functional magnetic resonance imaging (fMRI) scans were performed on 82 HM patients and 59 HCs who were closely matched for age, sex, and weight. Seed-based FC analysis was performed to identify alterations in the sFC and dFC patterns of the V1 in HM patients and HCs. Associations between mean sFC and dFC signal values and clinical symptoms in distinct brain areas among HM patients were identified via correlation analysis. Static and dynamic changes in brain activity in HM patients were investigated by assessments of sFC and dFC via calculation of the total time series mean and sliding-window analysis. Results: In the left anterior cingulate gyrus (L-ACG)/left superior parietal gyrus (L-SPG) and left V1, sFC values were significantly greater in HM patients than in HCs. In the L-ACG and right V1, sFC values were also significantly greater in HM patients than in HCs [two-tailed, voxel-level P < 0.01, Gaussian random field (GRF) correction, cluster-level P < 0.05]. In the left calcarine cortex (L-CAL) and left V1, dFC values were significantly lower in HM patients than in HCs. In the right lingual gyrus (R-LING) and right V1, dFC values were also significantly lower in HM patients than in HCs (two-tailed, voxel-level P < 0.01, GRF correction, cluster-level P < 0.05). Conclusion: Patients with HM exhibited significantly disturbed FC between the V1 and various brain regions, including L-ACG, L-SPG, L-CAL, and R-LING. This disturbance suggests that patients with HM could exhibit impaired cognitive and emotional processing functions, top-down control of visual attention, and visual information processing functions. HM patients and HCs could be distinguished from each other with high accuracy using sFC and dFC variabilities. These findings may help to identify the neural mechanism of decreased visual performance in HM patients.

4.
Front Hum Neurosci ; 16: 959523, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992950

RESUMO

Aim: Patients with high myopia (HM) reportedly exhibit changes in functional brain activity, but the mechanism underlying such changes is unclear. This study was conducted to observe differences in dynamic spontaneous brain activity between patients with HM and healthy controls (HCs) via dynamic regional homogeneity (dReHo) analysis. Methods: Resting-state functional magnetic resonance imaging (rs-fMRI) scans were performed on 82 patients with HM and 59 HCs who were closely matched for age, sex, and weight. The dReHo approach was used to assess local dynamic activity in the human brain. The association between mean dReHo signal values and clinical symptoms in distinct brain areas in patients with HM was determined via correlation analysis. Results: In the left fusiform gyrus (L-FG), right inferior temporal gyrus (R-ITG), right Rolandic operculum (R-ROL), right postcentral gyrus (R-PoCG), and right precentral gyrus (R-PreCG), dReHo values were significantly greater in patients with HM than in HCs. Conclusion: Patients with HM have distinct functional changes in various brain regions that mainly include the L-FG, R-ITG, R-ROL, R-PoCG, and R-PreCG. These findings constitute important evidence for the roles of brain networks in the pathophysiological mechanisms of HM and may aid in the diagnosis of HM.

5.
Front Hum Neurosci ; 16: 870350, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496062

RESUMO

Aim: Resting state functional magnetic resonance imaging (rs-fMRI) was used to analyze changes in functional connectivity (FC) within various brain networks and functional network connectivity (FNC) among various brain regions in patients with high myopia (HM). Methods: rs-fMRI was used to scan 82 patients with HM (HM group) and 59 healthy control volunteers (HC group) matched for age, sex, and education level. Fourteen resting state networks (RSNs) were extracted, of which 11 were positive. Then, the FCs and FNCs of RSNs in HM patients were examined by independent component analysis (ICA). Results: Compared with the HC group, FC in visual network 1 (VN1), dorsal attention network (DAN), auditory network 2 (AN2), visual network 3 (VN3), and sensorimotor network (SMN) significantly increased in the HM group. FC in default mode network 1 (DMN1) significantly decreased. Furthermore, some brain regions in default mode network 2 (DMN2), default mode network 3 (DMN3), auditory network 1 (AN1), executive control network (ECN), and significance network (SN) increased while others decreased. FNC analysis also showed that the network connection between the default mode network (DMN) and cerebellar network (CER) was enhanced in the HM group. Conclusion: Compared with HCs, HM patients showed neural activity dysfunction within and between specific brain networks, particularly in the DMN and CER. Thus, HM patients may have deficits in visual, cognitive, and motor balance functions.

6.
Neural Regen Res ; 16(2): 350-356, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32859797

RESUMO

Flavonoids have been reported to have therapeutic potential for spinal cord injury. Hawthorn leaves have abundant content and species of total flavonoids, and studies of the effects of the total flavonoids of hawthorn leaves on spinal cord injury have not been published in or outside China. Therefore, Sprague-Dawley rats were used to establish a spinal cord injury model by Allen's method. Rats were intraperitoneally injected with 0.2 mL of different concentrations of total flavonoids of hawthorn leaves (5, 10, and 20 mg/kg) after spinal cord injury. Injections were administered once every 6 hours, three times a day, for 14 days. After treatment with various concentrations of total flavonoids of hawthorn leaves, the Basso, Beattie, and Bresnahan scores and histological staining indicated decreases in the lesion cavity and number of apoptotic cells of the injured spinal cord tissue; the morphological arrangement of the myelin sheath and nerve cells tended to be regular; and the Nissl bodies in neurons increased. The Basso, Beattie, and Bresnahan scores of treated spinal cord injury rats were increased. Western blot assays showed that the expression levels of pro-apoptotic Bax and cleaved caspase-3 were decreased, but the expression level of the anti-apoptotic Bcl-2 protein was increased. The improvement of the above physiological indicators showed a dose-dependent relationship with the concentration of total flavonoids of hawthorn leaves. The above findings confirm that total flavonoids of hawthorn leaves can reduce apoptosis and exert neuroprotective effects to promote the recovery of the motor function of rats with spinal cord injury. This study was approved by the Ethics Committee of the Guangxi Medical University of China (approval No. 201810042) in October 2018.

7.
J Craniofac Surg ; 28(6): 1462-1467, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28708646

RESUMO

BACKGROUND: Cultured epithelial cells transplantation is a known surgical technique for vitiligo. OBJECTIVE: To evaluate the factors influencing efficacy and safety of cultured epithelial cells transplantation in 9-month follow-up. METHODS: Demographic, clinical, and repigmentation outcomes were reviewed for patients with facial segmental vitiligo who had undergone cultured epithelial cells transplantation from November 2013 to July 2015 at the clinic of the Department of Dermatology, Huashan Hospital, China. RESULTS: Twenty-eight patients who had undergone cultured epithelial cells transplantation were included. A satisfactory result (>50% repigmentation) was achieved in 79% patients with facial segmental vitiligo in 9 months. The treatment effect was significantly different in 6th month (P = 0.032), 9th month (P = 0.006) compared with 3rd month. Disease stability did significantly affect repigmentation outcome in 9th month (Z = 2.113, P = 0.035). No significant difference was observed between single segmental type versus mixed type (Z = 1.081, P = 0.280). Adverse effects were nearly absent. CONCLUSION: Cultured epithelial cells transplantation is a relatively safe and effective therapy for facial segmental stable vitiligo patients.


Assuntos
Transplante de Células/métodos , Células Cultivadas/transplante , Células Epiteliais/transplante , Face/fisiopatologia , Vitiligo , Humanos , Vitiligo/fisiopatologia , Vitiligo/terapia
8.
Arch Dermatol Res ; 308(10): 723-731, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27722782

RESUMO

Hydrogen peroxide (H2O2) may have a biphasic effect on melanin synthesis and melanosome transfer. High H2O2 concentrations are involved in impaired melanosome transfer in vitiligo. However, low H2O2 concentration promotes the beneficial proliferation and migration of melanocytes. The aim of this study was to explore low H2O2 and its mechanism in melanosome transfer, protease-activated receptor-2 (PAR-2) expression and calcium balance. Melanosomes were fluorescein-labeled for clear visualization of their transfer. The expression of protease-activated receptor-2 (PAR-2) in keratinocytes was determined by western blot analysis. Flow cytometry was employed to evaluate the effects of H2O2 on calcium levels in keratinocytes. Fluorescence microscopy showed the upregulation of melanosome transfer into keratinocytes following 0.3 mM H2O2 treatment in the co-cultures rather than in the untreated control groups, which was associated with higher expression of PAR-2 protein and increased calcium concentration. The addition of a PAR-2 antagonist inhibited the positive activity of H2O2 and calcium flow in keratinocytes. When calcium flow was blocked by a calcium chelator, the addition of H2O2 did not increase the PAR-2 expression level in keratinocytes, therefore, inhibiting dendrite formation and melanosome transfer. Low H2O2 concentration promotes melanosome transfer with increased PAR-2 expression level and calcium concentration in keratinocytes. In addition, the interaction between melanocytes and keratinocytes is more beneficial to enhance calcium levels in keratinocytes which mediate melanin transfer. Moreover, low H2O2 concentration promotes dendrite formation, in which extracellular calcium and Par-2 were involved.


Assuntos
Cálcio/metabolismo , Peróxido de Hidrogênio/farmacologia , Queratinócitos/efeitos dos fármacos , Melanócitos/efeitos dos fármacos , Oxidantes/farmacologia , Receptor PAR-2/metabolismo , Western Blotting , Células Cultivadas , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Citometria de Fluxo , Humanos , Peróxido de Hidrogênio/administração & dosagem , Queratinócitos/metabolismo , Melaninas/metabolismo , Melanócitos/metabolismo , Melanossomas/efeitos dos fármacos , Melanossomas/metabolismo , Microscopia de Fluorescência , Oxidantes/administração & dosagem , Cultura Primária de Células , Receptor PAR-2/antagonistas & inibidores , Regulação para Cima , Vitiligo/metabolismo
9.
Asian Pac J Cancer Prev ; 15(18): 7919-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25292087

RESUMO

20(S)-Protopanaxadiol (PPD), a ginsenoside isolated from Pananx quinquefolium L., has been shown to inhibit growth and proliferation in several cancer cell lines. The aim of this study was to evaluate its anticancer activity in human breast cancer cells. MCF-7 cells were incubated with different concentrations of 20(S)-PPD and cytotoxicity was evaluated by MTT assay. Occurrence of apoptosis was detected by DAPI and Annexin V-FITC/PI double staining. Mitochondrial membrane potential was measured with Rhodamine 123. The Bcl-2 and Bax expression were determined by Western blot analysis. Caspase activity was measured by colorimetric assay. 20(S)-PPD dose-dependently inhibited cell proliferation in MCF-7 cells, with an IC50 value of 33.3 µM at 24h. MCF-7 cells treated with 20(S)-PPD presented typical apoptosis, as observed by morphological analysis in cell stained with DAPI. The percentages of annexin V-FITC positive cells were 8.92%, 17.8%, 24.5% and 30.5% in MCF-7 cells treated with 0, 15, 30 and 60µM of 20(S)-PPD, respectively. Moreover, 20(S)-PPD could induce mitochondrial membrane potential loss, up-regulate Bax expression and down-regulate Bcl-2 expression. These events paralleled activation of caspase-9, -3 and PARP cleavage. Apoptosis induced by 20(S)-PPD was blocked by z-VAD-fmk, a pan-caspase inhibitor, suggesting induction of caspase-mediated apoptotic cell death. In conclusion, the 20(S)-PPD investigated is able to inhibit cell proliferation and to induce cancer cell death by a caspase-mediated apoptosis pathway.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Caspases/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Sapogeninas/farmacologia , Antidepressivos/farmacologia , Western Blotting , Neoplasias da Mama/enzimologia , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Feminino , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Transdução de Sinais , Células Tumorais Cultivadas
10.
Case Rep Dermatol ; 4(2): 163-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22949898

RESUMO

We report a unique case of multicentric reticulohistiocytosis (MRH) associated with liver carcinoma. A 61-year-old man presented with a 4-month history of nonpruritic, generalized, ruby-red papules and nodules, accompanied by fever, joint swelling and difficulty in swallowing. Skin histology showed polymorphic histiocyte infiltration with typical 'ground glass' cytoplasm. Further immunohistochemical studies characterized the lesions as positive for leukocyte common antigen, HLA-DR and CD68. The patient had a history of hepatitis B, and systemic examination, including carcinoma index and type-B ultrasonic examination, revealed high levels of AFP and a solid tumor, which was considered malignant, localized on the right lobe of the liver. Treatment of the liver carcinoma resulted in a significant improvement of the skin symptoms. This is the first case study to report an association between MRH and liver carcinoma. A review of the English-language literature reveals the close linkage between MRH and malignancy. All patients with MRH should be evaluated and monitored carefully to determine the underlying neoplasm.

11.
PLoS One ; 7(12): e52778, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23300773

RESUMO

BACKGROUND: Low vitamin D levels have been noted in patients with a variety of autoimmune diseases. A recent study showed that low vitamin D levels may be associated with vitiligo. OBJECTIVES: To assess 25-hydroxyvitamin D (25(OH)D) status in Chinese patients with vitiligo in comparison of normal controls and explore possible affecting factors. METHODS: We performed a case-control study including 171 patients, 50 controls in 25(OH)D lowest months and 30 patients, 20 controls in 25(OH)D highest months. Demographic and clinical variables of patients were analyzed to determine the correlation with 25(OH) D levels. RESULTS: 25(OH)D mean value of patients was highest in September and October, lowest in March. None of the patients and normal controls had 'sufficient' 25(OH)D (> = 75 nmol/L). No significant difference was found in either 25(OH)D mean values or insufficiency/deficiency ratio between patients and controls in 25(OH)D highest and lowest periods. Female patients were at a higher risk of 25(OH)D deficiency than male patients(P = 0.019). For non-segmental type, patients with 25(OH)D deficiency were more likely to have autoimmune thyroid disease than those with insufficiency (P = 0.016). Sex (P = 0.035), thyroid conditions (p = 0.034), testing month (p = 0.049) were independent factors affecting 25(OH)D level in multivariate analysis. CONCLUSION: Chinese population lack 25(OH)D universally. 25(OH)D level shows no correlation with onset of vitiligo in Chinese. However deficient 25(OH)D level may be linked to autoimmune disorders in patients.


Assuntos
Deficiência de Vitamina D , Vitamina D/análogos & derivados , Vitiligo/sangue , Adolescente , Adulto , Estudos de Casos e Controles , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Vitamina D/sangue , Adulto Jovem
12.
Am J Clin Dermatol ; 12(4): 277-81, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21668034

RESUMO

BACKGROUND: Childhood vitiligo is a common pediatric skin disorder. The pathogenesis of vitiligo is unclear, and immunological dysfunction may play an important role. OBJECTIVES: This prospective study aimed to profile childhood vitiligo and to discuss its correlation with immunological dysfunction. METHODS: All of the 620 enrolled patients were aged younger than 14 years, and were assessed with a standard questionnaire. The levels of immunoglobulins, complement, and T-lymphocyte subsets were measured in 270 of these 620 patients. RESULTS: Of the 620 children, 302 (48.71%) were boys and 318 (51.29%) were girls, with an average disease onset age of 7.57 years. The average duration was 13.45 months. 453 (73.06%) children had head and neck involvement and 160 (25.81%) children had segmental vitiligo. 84 (13.55%) children had a family history. There was a correlation between the disease and seasons. The onset or progression usually occurred in summer and spring. Halo nevus was seen in both segmental and non-segmental vitiligo. Precipitating factors such as stress appeared more commonly in segmental vitiligo. As to the immunological findings, in segmental vitiligo, the levels of C3 and C4 were lower in the active relative to the quiescent stage (p < 0.05); and in non-segmental vitiligo, the percentages of CD3+ and CD4+ lymphocytes and the CD4+/CD8+ ratio were lower in the active relative to the quiescent stage (p < 0.01). CONCLUSIONS: Childhood vitiligo has its own clinical features. The different types of vitiligo have different characteristics. There is immunological dysfunction in children with vitiligo. Dysfunction of humoral immunity may play a role in the progression of segmental vitiligo, while non-segmental vitiligo is more related to cellular immunity.


Assuntos
Imunidade Celular , Imunidade Humoral , Vitiligo/imunologia , Adolescente , Idade de Início , Criança , China , Proteínas do Sistema Complemento/metabolismo , Progressão da Doença , Feminino , Humanos , Imunoglobulinas/sangue , Masculino , Estudos Prospectivos , Estações do Ano , Inquéritos e Questionários , Subpopulações de Linfócitos T/imunologia , Vitiligo/patologia
13.
Dermatol Surg ; 37(7): 999-1006, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21492308

RESUMO

BACKGROUND: Of various surgical therapies used for the replenishment of melanocytes in recalcitrant and stable vitiligo, suction blister epidermal grafting (SBEG) is one of the simplest and most effective methods. OBJECTIVE: To evaluate the effectiveness and potential complications of SBEG in the treatment of stable vitiligo through the use of a modified dermis-epidermis separator designed by the authors. MATERIALS AND METHODS: One thousand one hundred people with stable vitiligo unresponsive to other medical treatments were treated with SBEG therapy. The negative pressure generated by the dermis-epidermis separator raised blisters at recipient and donor sites. Repigmentation was assessed 6 months after epidermis transplantation. RESULTS: Complete repigmentation was observed in 227 patients (20.6%), and excellent repigmentation (>50%) was observed in 568 (51.6%)-a success rate of 72.3%. No superficial scarring was observed at the grafted or donor sites, and no serious complications were encountered. CONCLUSION: SBEG is an established, simple, and effective treatment for resistant and stable vitiligo. Patients suffer few complications and are receptive to this type of therapy.


Assuntos
Epiderme/transplante , Vitiligo/cirurgia , Adolescente , Adulto , Idoso , Vesícula , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante de Pele/efeitos adversos , Transplante de Pele/instrumentação , Transplante de Pele/métodos , Sucção , Resultado do Tratamento , Adulto Jovem
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