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1.
Life Sci ; 237: 116949, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605712

RESUMO

AIMS: New-onset atrial fibrillation (AF) is frequently observed following acute stroke. The aim of this study was to investigate the effects of the brain-stellate ganglion-atrium network on AF vulnerability in a canine model with acute middle cerebral artery occlusion (MCAO). MATERIALS AND METHODS: Twenty-six dogs were randomly divided into the sham-operated group (n = 6), acute stroke (AS) group (n = 7), stellate ganglion ablation (SGA) group (n = 6) and clodronate liposome (CL) group (n = 7). In the sham-operated group, dogs received craniotomy without MCAO. Cerebral ischemic model was established in AS dogs by right MCAO. Right MCAO along with SGA and CL injection into the atrium was performed in SGA and CL dogs, respectively. After 3 days, atrial electrophysiology, neural activity, and the phenotype and function of macrophages in the atrium were studied in all the dogs. KEY FINDINGS: Higher AF inducibility (24.4 ±â€¯4.4% versus 4.4 ±â€¯2.2%, P < 0.05) and AF duration (15.7 ±â€¯3.8 s versus 2.6 ±â€¯1.1 s, P < 0.05) were observed in the AS group compared with the sham-operated group, and were associated with increased left stellate ganglion activity, higher macrophage infiltration and higher levels of inflammatory cytokines in the atrium. SGA or CL injection sharply suppressed AF inducibility (5.5 ±â€¯2.7% versus 24.4 ±â€¯4.4%; 5.3 ±â€¯3.2% versus 24.4 ±â€¯4.4%, both P < 0.05) and AF duration (2.9 ±â€¯1.2 s versus 15.7 ±â€¯3.8 s; 3.6 ±â€¯1.0 s versus 15.7 ±â€¯3.8 s, both P < 0.05) in canines with acute stroke. SIGNIFICANCE: A brain-stellate ganglion-atrium network may increase AF vulnerability through macrophage activation after acute stroke.


Assuntos
Fibrilação Atrial/patologia , Modelos Animais de Doenças , Átrios do Coração/fisiopatologia , Infarto da Artéria Cerebral Média/fisiopatologia , Macrófagos/patologia , Gânglio Estrelado/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Fibrilação Atrial/etiologia , Cães
2.
ACS Appl Mater Interfaces ; 10(51): 44796-44802, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30500152

RESUMO

Direct writing techniques for the printing of colloidal multiwalled carbon nanotubes (CNTs) embedded in polydimethylsiloxane (PDMS) were developed herein to fabricate complex structures including woodpiles, tetragonal scaffolds, and gradient mesh structures. The multiwalled CNTs served as a conductive filler and thickening agent for the printing ink. A suitable rheological behavior was obtained by mixing the CNTs with PDMS dissolved in an isopropyl alcohol solvent. A 7 wt % CNT loading in the PDMS was optimum for printing gap-spanning features at a nozzle moving speed of 20 mm/s. The printed structures, including a woodpile and gradient mesh structure, were capable of detecting changes in external mechanical pressure. Printed CNT/PDMS strips exhibit electrical actuation with good mechanical performance (strain of 8.9%) at a low actuation voltage (60 V). The performance characterization and application display demonstrated the possibility of developing custom complex CNT/PDMS structures for a broad range of applications, including soft robots and flexible electronic devices.

3.
Neuropsychiatr Dis Treat ; 14: 3317-3327, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30584305

RESUMO

Background: Previous studies demonstrated that early blindness is associated with abnormal intrinsic functional connectivity (FC) between the primary visual cortex (V1) and other sensory areas. However, the V1 pattern of spontaneous neural activity occurring in late blindness (LB) remains unknown. The purpose of this study was to investigate the intrinsic FC patterns of V1 in LB. Materials and methods: Thirty LB individuals (18 males and 12 females; mean age: 38.76±14.43 years) and 30 sighted controls (SCs) individuals (18 males and 12 females; mean age: 38.67±13.85 years) closely matched for age, sex, and education, underwent resting-state magnetic resonance imaging scans. Region of interest analysis was performed to extract the correlation coefficient matrix among each pair of Brodmann area (BA) 17 and FC between V1 and vision-related subcortical nuclei. Results: Compared with SCs, LB individuals showed a decreased FC between the left V1 and the bilateral cuneus (CUN)/lingual gyrus (LGG)/calcarine (CAL) (BA 18/19/30) and left precentral gyrus (PreCG) and the postcentral gyrus (PostCG) (BA 2/3/4). Also, LB individuals showed a decreased FC between the right V1 and the bilateral CUN/LGG/CAL (BA 18/19/30) and the left PreCG and PostCG (BA 2/3/4/6) (voxel-level: P<0.01, cluster-level: P<0.05). Meanwhile, LB individuals showed a decreased FC between the left V1 and the right V1 and increased FC between the left V1 and the right superior colliculus, the right V1, and the left hippocampus (P<0.05). Moreover, a positive correlation was observed between the onset age of blindness and FC values in V1 to CUN/LGG/CAL in LB. Conclusion: Our results highlighted that LB induces a decreased FC between V1 and higher visual areas, motor cortices, and somatosensory cortices at rest. This might indicate that LB humans could present with impaired top-down modulations, visual imagery, and vision-motor function.

4.
Hypertens Pregnancy ; 36(1): 48-52, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27834501

RESUMO

OBJECTIVE: Preeclampsia (PE) is a disorder of pregnancy marked by hypertension and proteinuria with no known treatment aside from pregnancy termination. The pathogenesis of PE is poorly understood, but is thought to originate in the placenta. We assessed the value of measuring serum and urinary soluble deformylase-like tyrosine kinase receptor 1 (sFlt-1), a known target of placental factors, and placental growth factor (PLGF), a key placental signaling molecule, in the diagnosis of PE. METHODS: Eighty patients with PE were classified as either exhibiting mild (44 cases) or severe (36 cases) symptoms of PE. Forty normal pregnant women were selected as controls. Serum and urinary PLGF and sFlt-1 levels, along with the ratio of sFlt-1 to PLGF, were compared across groups. RESULTS: Serum and urinary sFlt-1 and sFlt-1/PLGF ratios in severe PE patients were significantly higher than those in the mild PE group, and measurements from mild PE patients were significantly higher than controls (all P values <0.01). The serum and urinary PLGF levels in severe PE patients were significantly lower than mild PE patients, and mild PE patients had significantly lower PLGF levels than controls (all P values <0.01). As expected, serum sFlt-1 and PLGF levels and ratios were highly correlated with urinary sFlt-1 and PLGF levels and ratios. CONCLUSIONS: The severity of PE was closely correlated with these measurements, suggesting that they may be useful tools in the diagnosis and evaluation of PE.


Assuntos
Fator de Crescimento Placentário/metabolismo , Pré-Eclâmpsia/diagnóstico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Humanos , Fator de Crescimento Placentário/sangue , Fator de Crescimento Placentário/urina , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/urina , Gravidez , Segundo Trimestre da Gravidez/sangue , Segundo Trimestre da Gravidez/urina , Índice de Gravidade de Doença , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/urina , Adulto Jovem
5.
J Affect Disord ; 131(1-3): 299-306, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21236494

RESUMO

OBJECTIVE: In bipolar disorder, white matter abnormalities have been reported with region-of-interest and voxel-based methods; however, deficits in specific white matter tracts cannot be localized by these methods. Therefore, in this study, we aimed to investigate the white matter tracts that mediate connectivity of the frontal cortex using diffusion tensor imaging (DTI) tractography. METHODS: Eighteen patients with bipolar disorder and sixteen age- and gender-matched healthy subjects underwent DTI examinations. Frontal cortex white matter tracts, including the anterior thalamic radiation (ATR), uncinate fasciculus (UF), superior longitudinal fasciculus (SLF), cingulum, and inferior fronto-occipital fasciculus (IFO) were reconstructed by DTI tractography, and we calculated the mean fractional anisotropy (FA) for each fiber tract. The values were compared between groups by repeated measures analysis of variance with age and gender as covariates, which allowed us to investigate significant differences between the tracts. RESULTS: When compared with healthy controls, the patients with bipolar disorder showed significantly decreased FA in the ATR and UF, and a trend towards lower FA in the SLF and cingulum. However, there were no FA differences between groups in the IFO. CONCLUSIONS: Our study indicates that bipolar patients show abnormalities within white matter tracts connecting the frontal cortex with the temporal and parietal cortices and the fronto-subcortical circuits. These findings suggest that alterations in the connectivity of white matter tracts in the frontal cortex might contribute to the neuropathology of bipolar disorder.


Assuntos
Transtorno Bipolar/patologia , Lobo Frontal/patologia , Adulto , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Vias Neurais/patologia
6.
Int J Pharm ; 325(1-2): 194-6, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16901662

RESUMO

In an attempt to prepare uniformly sized biodegradable microparticles for controllable drug eluting and targeting characteristics, a novel technique by employing ultrashort pulse (USP) laser has been developed. This method involves pumping a drug-polymer solution through a small orifice creating a liquid stream. A USP laser constantly fires at the stream to cut it into discrete droplets and consequently solid particles can be obtained with monodisperse size distribution. Through mathematical modeling, volumetric flow rate, orifice size, laser spot size, and laser frequency were found as sole factors determining the size profile of the resulting microparticles. By choosing appropriate set of variables, monosized biodegradable microparticles with wide range of particle size may be prepared.


Assuntos
Lasers , Microesferas , Tecnologia Farmacêutica/métodos , Algoritmos , Materiais Biocompatíveis , Biodegradação Ambiental , Portadores de Fármacos/química , Ácido Láctico/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/química , Tecnologia Farmacêutica/instrumentação
7.
Zhonghua Yan Ke Za Zhi ; 42(3): 222-5, 2006 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16643753

RESUMO

OBJECTIVE: To study the growth aspects of orbital volume and to establish the normal value of orbital volume by computed tomography (CT). METHODS: One hundred and twenty three individuals without eye diseases (64 males, 59 females) were divided into 5 groups according to the age. Orbital volume and length of horizontal transverse axis and anterior-posterior axis of the eye were measured at different levels in original or reconstructive CT images. The relationship between orbital volume and age, gender and eyeball volume was analyzed. RESULTS: There was no difference between the left and right orbital volume in all age groups. Orbital volume grew rapidly before 20 years of old. Mean orbital volume in males aged 17 and females aged 13 was 23.54 and 21.75 ml, respectively, which reached 95% of the adult orbital volume. In normal adult, orbital volume in the male was larger than that of the female. The mean orbital volume of adult male and female was (25.04 +/- 2.37) ml and (22.89 +/- 2.67) ml, respectively. A strong linear correlation was presented between the age and orbital volume (P < 0.05). The difference of orbital volume between the male and female was statistically non-significant before 14 years old (P = 0.315). The growth of eyeball volume was consistent with that of the orbital volume, the ratio of eyeball/orbit volume was decreased with age from 0.40 to 0.26. CONCLUSIONS: There is no difference between the right and left orbital volume. Orbital volume is correlated with age and gender. Orbital volume grows rapidly before 20 years of old and still grows slowly after 40 years old.


Assuntos
Órbita/diagnóstico por imagem , Órbita/crescimento & desenvolvimento , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antropometria , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , Tomografia Computadorizada por Raios X
8.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(3): 171-3, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15760532

RESUMO

OBJECTIVE: To observe the effect of combined decompression operation on patients with severe traumatic brain injury complicated by tentorial cerebral herniation. METHODS: Ninety-seven patients with an admission Glasgow Coma Scale score 3-5 were randomly divided into two groups: combined decompression group (n=46), in whom tentorium cerebelli was incised (2-4 cm) combined with bone flap craniectomy decompression [(10-15)cm x (15-17)cm], and conventional temporoparietal craniectomy group (n=51). CT scanning was performed in the patients before and after the operation. The patients of both groups received routine treatment and followed up for 1-32 months (mean 7 months) after the operation. The clinical symptoms, change in intracranial pressure and incidence of complications were compared between the two groups. RESULTS: The efficacious rate was 80.4% (37/46) in the combined decompression group, and among them 27 patients were cured (58.7%) and 10 patients remained to have moderate disability(21.7%). Nine patients (19.6%) died after combined decompression. However, in patients with conventional temporoparietal craniectomy decompression, favorable outcome was only found in 6 cases(11.8%), moderate disability accounted for 21.6% of patients, and 34 patients died(66.6%). In patients with combined decompression, the intracranial pressure was more efficiently lowered compared with conventional craniectomy decompression(P<0.01). Furthermore the incidence of acute brain edema, incisional herniation, traumatic epilepsy, occipital cerebral infarct and cerebro-spinal fluid(CSF) leakage were lower in combined decompression group compared with conventional craniectomy group (P<0.05 or P<0.01). The incidence of intracranial infection was not significantly different between two groups (P>0.05). CONCLUSION: Combined decompression is preferable to routine temporoparietal craniectomy for patients with severe head injury complicated by tentorial herniation.


Assuntos
Descompressão Cirúrgica/métodos , Encefalocele/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
9.
Artigo em Chinês | MEDLINE | ID: mdl-14768084

RESUMO

OBJECTIVE: To investigate the clinical application of self-cranial bone powder in one stage cranioplasty. METHODS: From October 1999 to December 2002, self-cranial bone powder and medical adhesive were used to repair the skull defect, for one stage cranioplasty, caused by operations on cranium in 128 cases of severe dangerous craniocerebral injury, acute intracranial hematome, sick skull and intracranial tumor. The bone growth was observed by CT or X-ray examination 3-24 months after replantation of cranioplasty. RESULTS: The decompression and cranioplasty were performed simultaneously, the time prolonged 5-10 minutes than that of routine, the appearance of repaired cranial bone was normal, without concavity and convexity. After 12 months of operation, the replanted bone merged with the normal bone completely, with normal appearance. The operation successful rate was 96.1% (123/125) without any complication. Only five cases were not better in growing because of less bone powder, but without cerebral pulse and defective syndrome. All the cases did not need secondary cranioplasty. CONCLUSION: The effect of cranioplasty with self- cranial bone powder effect is good in taking shape. This new method can avoid the traditional secondary cranioplasty for skull defect and complications.


Assuntos
Transplante Ósseo/métodos , Traumatismos Craniocerebrais/cirurgia , Craniotomia , Crânio/cirurgia , Adolescente , Adulto , Idoso , Regeneração Óssea , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Pós , Procedimentos Cirúrgicos Reconstrutivos , Crânio/diagnóstico por imagem , Crânio/lesões , Adesivos Teciduais/uso terapêutico , Tomografia Computadorizada por Raios X
11.
Zhonghua Er Bi Yan Hou Ke Za Zhi ; 37(1): 38-40, 2002 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-12768793

RESUMO

OBJECTIVE: To measure the ostium area of normal maxillary sinus and maxillary sinus with inflammation on virtual endoscopy. METHODS: After scanning on coronal or axial position, data were transferred to workstation. Such anatomic structures as ostiomeatal complex (OMC) were viewed by virtual endoscopy (VE). Under the same condition, pixel/mm was worked out. RESULTS: Turbinates, meati and ostiomeatal complex were clearly viewed by virtual endoscopy(VE). The area of normal maxillary ostium was (16.45 +/- 1.21) mm2; the area of abnormal ostium was (18.28 +/- 2.12) mm2. The outside area of ethmoid infundibulum was (15.07 +/- 0.78) mm2 with normal maxillary sinus, and (17.19 +/- 1.59) mm2 maxillary sinus with inflamed. CONCLUSIONS: The areas of mormal and inflamed maxillary sinuses are equal, the outside areas of ethmoid infundibulum are unequal for normal maxillary sinus and maxillary sinus with inflammation.


Assuntos
Seio Maxilar/diagnóstico por imagem , Sinusite Maxilar/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Imagem Tridimensional , Masculino , Seio Maxilar/anatomia & histologia , Pessoa de Meia-Idade
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