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1.
EMBO J ; 40(14): e107341, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34037273

RESUMO

Apoptotic cell death is implicated in both physiological and pathological processes. Since many types of cancerous cells intrinsically evade apoptotic elimination, induction of apoptosis has become an attractive and often necessary cancer therapeutic approach. Conversely, some cells are extremely sensitive to apoptotic stimuli leading to neurodegenerative disease and immune pathologies. However, due to several challenges, pharmacological inhibition of apoptosis is still only a recently emerging strategy to combat pathological cell loss. Here, we describe several key steps in the intrinsic (mitochondrial) apoptosis pathway that represent potential targets for inhibitors in disease contexts. We also discuss the mechanisms of action, advantages and limitations of small-molecule and peptide-based inhibitors that have been developed to date. These inhibitors serve as important research tools to dissect apoptotic signalling and may foster new treatments to reduce unwanted cell loss.


Assuntos
Apoptose/fisiologia , Animais , Humanos , Mitocôndrias/patologia , Neoplasias/patologia , Doenças Neurodegenerativas/patologia , Transdução de Sinais/fisiologia
2.
J Immunol ; 209(1): 180-191, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35725271

RESUMO

The pharmacological inhibition of IDO1 is considered an effective therapeutic approach for cancer treatment. However, the inadequate response of existing holo-IDO1 inhibitors and unclear biomarkers available in clinical practice limit the possibility of developing efficacious IDO1 inhibitors. In the current study, we aimed to elucidate the activity and mechanism of a potent 1H-pyrrole-2-carboxylic acid derivative (B37) targeting apo-IDO1 and to determine its role in tumor therapy. By competing with heme for binding to apo-IDO1, B37 potently inhibited IDO1 activity, with an IC50 of 22 pM assessed using a HeLa cell-based assay. The x-ray cocrystal structure of the inhibitor-enzyme complex showed that the B37-human IDO1 complex has strong hydrophobic interactions, which enhances its binding affinity, determined using isothermal titration calorimetry. Stronger noncovalent interactions, including π stacking and hydrogen bonds formed between B37 and apo-human IDO1, underlay the enthalpy-driven force for B37 for binding to the enzyme. These binding properties endowed B37 with potent antitumor efficacy, which was confirmed in a mouse colon cancer CT26 syngeneic model in BALB/c mice and in an azoxymethane/dextran sulfate sodium-induced colon carcinogenesis model in C57BL/6 mice by activating the host immune system. Moreover, the combination of B37 and anti-PD1 Ab synergistically inhibited tumor growth. These results suggested that B37 may serve as a unique candidate for apo-IDO1 inhibition-mediated tumor immunotherapy.


Assuntos
Imunoterapia , Indolamina-Pirrol 2,3,-Dioxigenase , Animais , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
3.
Environ Geochem Health ; 45(11): 8169-8186, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37548849

RESUMO

Identifying the contamination and sources of potentially toxic elements (PTEs) in road-dust sediment (RDS) and the surrounding greenspace soil of urban environments and understanding their ecological-health risks are important for pollution management and public health. The contamination characteristics, ecological and probabilistic health risks, and source apportionment of eight PTEs (Cd, Pb, Cr, Cu, Ni, As, Zn, and Hg) in the Yellow River Custom Tourist Line of Lanzhou, which is the largest open urban riverfront scenic park in China, were investigated. The results showed that all the RDS PTE mean concentrations exceeded their soil background values, whereas for the surrounding greenspace soils, the concentrations of the PTEs, except for Cr and Ni, were also higher than their local background levels. Moreover, the RDS-soil system was mainly contaminated by Cd, Zn, Pb, Cu, and Hg to varying degrees, and the integrated ecological risks of PTEs in the RDS and soil were high and considerable at most sites, respectively. The probabilistic health risk assessment results demonstrated that the non-carcinogenic hazard risk for humans was negligible, but the total carcinogenic risks should be considered. Source apportionment using a positive matrix factorization model combined with multivariate statistical analyses revealed that Cr, Ni, and As in the RDS-soil system were from natural and industrial sources, Cd, Pb, Zn, Cu came from vehicle emissions and pesticide and fertilizer applications, and Hg was from natural and industrial sources and utilization of pesticides with fertilizers. This work provides scientific evidence for urban planning and human health protection in urban environments.


Assuntos
Mercúrio , Metais Pesados , Praguicidas , Poluentes do Solo , Humanos , Solo , Cádmio/análise , Chumbo/análise , Parques Recreativos , Monitoramento Ambiental/métodos , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Mercúrio/análise , China , Medição de Risco , Praguicidas/análise , Poeira/análise
4.
Toxicol Appl Pharmacol ; 438: 115909, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35134436

RESUMO

Emodin-8-O-ß-D-glucopyranoside (EG), a natural hydroxyanthraquinone glycoside from some traditional medicinal plants, has been demonstrated to have potential antitumor effects in our previous studies. Herein, we confirm that EG remains stable in the cell culture medium. It suppresses cell viability and proliferation and induces G1 cell cycle arrest in human colorectal cancer and neuroblastoma cells in vitro. EG inhibits tumor growth in human colorectal cancer cell HCT 116-bearing xenograft mice with low toxicity in the liver and kidney. The transcriptome analysis shows that the p53 signaling pathway is the most enriched cellular pathway and EG affects the proliferation of HCT 116 cells through modulating cell cycle related genes, such as CDKN1A and Cyclin-dependent kinases (CDKs). We demonstrate that the protein expression level of p21 was up-regulated, and CDK1/CDK2 were reduced significantly in both HCT 116 and SH-SY5Y cells after EG treatment. The switch from hypo- to hyper-phosphorylated Retinoblastoma (Rb), which is believed as a result of activated CDKs, was inhibited when cells were treated with EG. These findings indicate that EG suppresses cancer cell proliferation via p21-CDKs-Rb axis.


Assuntos
Antraquinonas/farmacologia , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Emodina/farmacologia , Glicosídeos/farmacologia , Proteína do Retinoblastoma/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosforilação/efeitos dos fármacos , Retinoblastoma/tratamento farmacológico , Retinoblastoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
5.
Mol Psychiatry ; 26(12): 7363-7371, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385597

RESUMO

Aberrant topological organization of whole-brain networks has been inconsistently reported in studies of patients with major depressive disorder (MDD), reflecting limited sample sizes. To address this issue, we utilized a big data sample of MDD patients from the REST-meta-MDD Project, including 821 MDD patients and 765 normal controls (NCs) from 16 sites. Using the Dosenbach 160 node atlas, we examined whole-brain functional networks and extracted topological features (e.g., global and local efficiency, nodal efficiency, and degree) using graph theory-based methods. Linear mixed-effect models were used for group comparisons to control for site variability; robustness of results was confirmed (e.g., multiple topological parameters, different node definitions, and several head motion control strategies were applied). We found decreased global and local efficiency in patients with MDD compared to NCs. At the nodal level, patients with MDD were characterized by decreased nodal degrees in the somatomotor network (SMN), dorsal attention network (DAN) and visual network (VN) and decreased nodal efficiency in the default mode network (DMN), SMN, DAN, and VN. These topological differences were mostly driven by recurrent MDD patients, rather than first-episode drug naive (FEDN) patients with MDD. In this highly powered multisite study, we observed disrupted topological architecture of functional brain networks in MDD, suggesting both locally and globally decreased efficiency in brain networks.


Assuntos
Transtorno Depressivo Maior , Encéfalo , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética/métodos , Vias Neurais , Tamanho da Amostra
6.
Proc Natl Acad Sci U S A ; 116(18): 9078-9083, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30979801

RESUMO

Major depressive disorder (MDD) is common and disabling, but its neuropathophysiology remains unclear. Most studies of functional brain networks in MDD have had limited statistical power and data analysis approaches have varied widely. The REST-meta-MDD Project of resting-state fMRI (R-fMRI) addresses these issues. Twenty-five research groups in China established the REST-meta-MDD Consortium by contributing R-fMRI data from 1,300 patients with MDD and 1,128 normal controls (NCs). Data were preprocessed locally with a standardized protocol before aggregated group analyses. We focused on functional connectivity (FC) within the default mode network (DMN), frequently reported to be increased in MDD. Instead, we found decreased DMN FC when we compared 848 patients with MDD to 794 NCs from 17 sites after data exclusion. We found FC reduction only in recurrent MDD, not in first-episode drug-naïve MDD. Decreased DMN FC was associated with medication usage but not with MDD duration. DMN FC was also positively related to symptom severity but only in recurrent MDD. Exploratory analyses also revealed alterations in FC of visual, sensory-motor, and dorsal attention networks in MDD. We confirmed the key role of DMN in MDD but found reduced rather than increased FC within the DMN. Future studies should test whether decreased DMN FC mediates response to treatment. All R-fMRI indices of data contributed by the REST-meta-MDD consortium are being shared publicly via the R-fMRI Maps Project.


Assuntos
Encéfalo/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Mapeamento Encefálico/métodos , China , Conectoma/métodos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/fisiopatologia , Descanso/fisiologia
7.
Sensors (Basel) ; 21(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34833774

RESUMO

Interrupted sampling repeater jamming (ISRJ) is an effective method for implementing deception jamming on chirp radars. By means of frequency-shifting jamming processing of the target echo signal and pulse compression during image processing, a group of false targets will appear in different spatial locations around the true target. Extracting the features of these false targets is complex and limited to existing countering methods against ISRJ. This paper proposes an anti-jamming method to identify the spatial location characteristics of two-dimensional deception false targets. By adjusting the parameters of the radar transmitted signal, the method simultaneously transmits the anti-jamming signal and carries out false target identification and elimination in the range and azimuth dimensions. Eventually, the optimal signal parameter design of the anti-jamming signal is obtained by comparing different anti-jamming strategies in the range dimension. The validity of the proposed method is proved by deducing the mathematical model between the spatial distribution characteristics of the false targets and the radar transmitted signal parameters and demonstrated by simulations.


Assuntos
Algoritmos , Enganação , Frequência Cardíaca , Modelos Teóricos , Radar
8.
Radiol Med ; 126(10): 1356-1365, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34160776

RESUMO

OBJECTIVES: The mechanism of orthodontic pain modulation with a placebo remains largely unknown. This study aimed to investigate the placebo modulation of brain activity associated with orthodontic pain using functional magnetic resonance imaging (fMRI). METHODS: This longitudinal fMRI experiment recruited 23 volunteers and a self-contrast method was used. At first time, the participants were scanned without placebo (first period), followed by a 30-day washout, the participants were scanned again with placebo administration (second period). Orthodontic pain was caused by orthodontic separators placement between the lower right molars for both two periods. 24 h after placement, the MRI scans were taken, including a bite/non-bite task fMRI and a resting-state fMRI. A generalized linear model was used to identify pain-regulating network from task fMRI. Functional connectivity analysis of pain-related brain regions was performed to study the placebo effect on connectivity of pain-regulating networks using resting-state fMRI. RESULTS: The results of brain activation patterns were largely similar under placebo and non-placebo conditions. Under the non-placebo condition, the activities in multiple brain regions, including the pre-central gyrus, superior frontal gyrus, superior parietal lobule, and supramarginal gyrus, were significantly higher than that of the placebo condition. However, the anterior cingulate cortex (ACC) was activated under the non-placebo condition but not in the placebo one. The functional connectivities between ACC and orbitofrontal cortex, and the dorsolateral prefrontal cortex and orbitofrontal cortex were reduced under placebo condition. CONCLUSION: Participants demonstrated similar brain activation patterns for orthodontic pain with or without placebos. With placebo, reduced activation in primary sensory cortex and decreased activation in ACC indicated that ACC could be fundamental in analgesia.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Aparelhos Ortodônticos Removíveis , Dor/fisiopatologia , Efeito Placebo , Feminino , Humanos , Estudos Longitudinais , Método Simples-Cego , Adulto Jovem
10.
Environ Geochem Health ; 42(11): 4037-4050, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32686071

RESUMO

Seafood has been generally considered to be the main diet exposure source of metal(loid)s. We evaluated health risk of mercury (Hg), arsenic (As), cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni), copper (Cu), and zinc (Zn) through consumption of cooked seafood based on bioaccessibility, which was obtained by physiologically based extraction test method. Results showed that cooking practices could decrease metal(loid)s concentration from seafood (by 6.0-45.7%). Metal(loid)s release from seafood in this study followed the descending order of Hg > Zn > Ni > Cd > Pb > As > Cu > Cr. On average, cooking lowered the bioaccessibility of As, Hg, Cd, Pb, Ni, Cr, Cu, and Zn by 15.2, 26.1, 30.9, 30.7, 25.7, 31.2, 17.6, and 22.4%, respectively. Health risk calculation results showed that Cr, Ni, and Zn in seafood species in this study were within the human health benefits range. Hg, Cd, Pb, and Cu exposure from cooked seafood was within the safe dose. However, we found that there is a potential of having cancer (especially bladder and lung cancer) for people exposure to iAs from seafood based on bioaccessible contents the first time.


Assuntos
Culinária , Contaminação de Alimentos/análise , Metais Pesados/análise , Alimentos Marinhos/efeitos adversos , Alimentos Marinhos/análise , Animais , Disponibilidade Biológica , Carcinógenos/análise , Carcinógenos/toxicidade , China , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Humanos , Neoplasias Pulmonares/induzido quimicamente , Metais Pesados/farmacocinética , Metais Pesados/toxicidade , Medição de Risco , Neoplasias da Bexiga Urinária/induzido quimicamente , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Hum Brain Mapp ; 40(17): 4877-4887, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31361385

RESUMO

Neuroimaging studies have revealed functional brain network abnormalities in attention deficit hyperactivity disorder (ADHD), but the results have been inconsistent, potentially related to confounding medication effects. Furthermore, specific topological alterations in functional networks and their role in behavioral inhibition dysfunction remain to be established. Resting-state functional magnetic resonance imaging was performed on 51 drug-naïve children with ADHD and 55 age-matched healthy controls. Brain functional networks were constructed by thresholding the partial correlation matrices of 90 brain regions, and graph theory was used to analyze network topological properties. The Stroop test was used to assess cognitive inhibitory abilities. Nonparametric permutation tests were used to compare the topological architectures in the two groups. Compared with healthy subjects, brain networks in ADHD patients demonstrated altered topological characteristics, including lower global (FDR q = 0.01) and local efficiency (p = 0.032, uncorrected) and a longer path length (FDR q = 0.01). Lower nodal efficiencies were found in the left inferior frontal gyrus and anterior cingulate cortex in the ADHD group (FDR both q < 0.05). Altered global and nodal topological efficiencies were associated with the severity of inhibitory cognitive control deficits and hyperactivity symptoms in ADHD (p <0 .05). Alterations in network topologies in drug-naïve ADHD patients indicate weaker small-worldization with decreased segregation and integration of functional brain networks. Deficits in the cingulo-fronto-parietal attention network were associated with inhibitory control deficits.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Mapeamento Encefálico , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem
12.
Langmuir ; 34(1): 351-358, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29215892

RESUMO

We performed molecular dynamics simulations to study the pH-induced structural transitions for aqueous mixtures of a cationic surfactant (cetyltrimethylammonium bromide, CTAB) and a hydrotrope (sodium salicylate, NaSal). We obtained rigid cylindrical, spherical, and flexible cylindrical micelles at pH 7, 2, and 0, respectively, which agrees well with the experimental results of Umeasiegbu et al. (Langmuir 2016, 32, 655). By analyzing the different micellar structural properties, including distribution and molecular orientation of CTA+ and Sal- inside the micelle, we found that the binding form of the protonated salicylate molecules with CTA+ is different from that of Sal- ions. Because of the protonation of salicylate molecules with reduction in pH, their hydrogen bonding interactions with water molecules strengthened and the electrostatic interactions with CTA+ headgroups weakened. Thus, the repulsion of the CTA+ headgroups led to the breakage of the cylindrical micelle into spherical ones. At pH 0, the H-bond-strengthened cation-π interactions between salicylate and CTA+ were verified. We concluded that the penetration of salicylate molecules inside the micelle and the strong association of Cl- ions on the micellar surface play a key role in the formation of a flexible cylindrical micelle. This work provides an atomic-level insight into the mechanism of pH-induced shape transitions in the CTAB/NaSal systems, which is expected to be helpful to understand the aggregate behavior of cationic surfactant-hydrotrope solution.

13.
Hum Brain Mapp ; 38(5): 2482-2494, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28176413

RESUMO

Major depressive disorder (MDD) has been associated with disruptions in the topological organization of brain morphological networks in group-level data. Such disruptions have not yet been identified in single-patients, which is needed to show relations with symptom severity and to evaluate their potential as biomarkers for illness. To address this issue, we conducted a cross-sectional structural brain network study of 33 treatment-naive, first-episode MDD patients and 33 age-, gender-, and education-matched healthy controls (HCs). Weighted graph-theory based network models were used to characterize the topological organization of brain networks between the two groups. Compared with HCs, MDD patients exhibited lower normalized global efficiency and higher modularity in their whole-brain morphological networks, suggesting impaired integration and increased segregation of morphological brain networks in the patients. Locally, MDD patients exhibited lower efficiency in anatomic organization for transferring information predominantly in default-mode regions including the hippocampus, parahippocampal gyrus, precuneus and superior parietal lobule, and higher efficiency in the insula, calcarine and posterior cingulate cortex, and in the cerebellum. Morphological connectivity comparisons revealed two subnetworks that exhibited higher connectivity strength in MDD mainly involving neocortex-striatum-thalamus-cerebellum and thalamo-hippocampal circuitry. MDD-related alterations correlated with symptom severity and differentiated individuals with MDD from HCs with a sensitivity of 87.9% and specificity of 81.8%. Our findings indicate that single subject grey matter morphological networks are often disrupted in clinically relevant ways in treatment-naive, first episode MDD patients. Circuit-specific changes in brain anatomic network organization suggest alterations in the efficiency of information transfer within particular brain networks in MDD. Hum Brain Mapp 38:2482-2494, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/patologia , Transtorno Depressivo Maior/patologia , Vias Neurais/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Escalas de Graduação Psiquiátrica , Curva ROC , Estatísticas não Paramétricas , Adulto Jovem
14.
J Psychiatry Neurosci ; 42(3): 150-163, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27780031

RESUMO

BACKGROUND: Multiple meta-analyses of diffusion tensor imaging (DTI) studies have reported impaired white matter integrity in patients with major depressive disorder (MDD). However, owing to inclusion of medicated patients in these studies, it is difficult to conclude whether these reported alterations are associated with MDD or confounded by medication effects. A meta-analysis of DTI studies on medication-free (medication-naive and medication washout) patients with MDD would therefore be necessary to disentangle MDD-specific effects. METHODS: We analyzed white matter alterations between medication-free patients with MDD and healthy controls using anisotropic effect size-signed differential mapping (AES-SDM). We used DTI query software for fibre tracking. RESULTS: Both pooled and subgroup meta-analyses in medication washout patients showed robust fractional anisotropy (FA) reductions in white matter of the right cerebellum hemispheric lobule, body of the corpus callosum (CC) and bilateral superior longitudinal fasciculus III (SLF III), whereas FA reductions in the genu of the CC and right anterior thalamic projections were seen in only medication-naive patients. Fibre tracking showed that the main tracts with observed FA reductions included the right cerebellar tracts, body of the CC, bilateral SLF III and arcuate fascicle. LIMITATIONS: The analytic techniques, patient characteristics and clinical variables of the included studies were heterogeneous; we could not exclude the effects of nondrug therapies owing to a lack of data. CONCLUSION: By excluding the confounding influences of current medication status, findings from the present study may provide a better understanding of the underlying neuropathology of MDD.


Assuntos
Encéfalo/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos
15.
Hum Brain Mapp ; 37(3): 954-67, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706823

RESUMO

The thalamus is a relay center between various subcortical brain areas and the cerebral cortex with delineation of its constituent nuclei being of particular interest in many applications. While previous studies have demonstrated efficacy of connectivity-based thalamus segmentation, they used approaches that do not consider the dynamic nature of thalamo-cortical interactions. In this study, we explicitly exploited the dynamic variation of thalamo-cortical connections to identify different states of functional connectivity and performed state-specific thalamus parcellation. With normalized spectral clustering successively applied in temporal and spatial domains, nine thalamo-cortical connectivity states were identified and the dynamic thalamus parcellation revealed finer thalamic structures with improved atlas correspondence. The present results extend our understanding of thalamo-cortical connectivity and provide a more comprehensive view of the thalamo-cortical interaction.


Assuntos
Imageamento por Ressonância Magnética/métodos , Tálamo/fisiologia , Córtex Cerebral/fisiologia , Conectoma , Conjuntos de Dados como Assunto , Humanos , Internet , Vias Neurais/fisiologia , Descanso
16.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(4): 618-623, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-28591973

RESUMO

OBJECTIVES: To evaluate the clinical application value of internal iliac artery balloon occlusion in pernicious placenta previa. METHODS: We retrospectively reviewed the medical records of the patients of pernicious placenta previa in a single center from Jan, 2010 to Jan, 2015. The patients were divided into two groups, internal iliac artery balloon occlusion group and the control group without endovascular intervention. Blood loss in operation, volume of transfused blood products, caesarean hysterectomy, operating time, hospital days after operation and postoperative morbidity were compared between the two groups. RESULTS: The balloon occlusion group had significantly less blood loss, the volume of transfused blood products, caesarean hysterectomy, hospital day after operation than the control group had. There was no statistical difference in operating time, intensive care units (ICU), hypotension, infection, hypoxemia, bladder injury, bowel obstruction, neonatal asphyxia between the two groups. The balloon occlusion group had significantly higher rate in coagulopathy, hypoalbuminemia, electrolyte imbalance. Among the patients whose uterus were preserved, the blood loss was not significantly difference between the two groups. Among the patients with the complication of placenta accreta, caesarean hysterectomy was less in balloon group, and blood loss between the two groups was not significantly different. Among the patients without placenta accrete, the blood loss was less in balloon group, and caesarean hysterectomy between the two groups was not significantly different. The risk of hysterectomy in balloon group was related to placenta accreta, uterine arteries engorgement, placental invasive serosa, taking placenta by hand, placental invasive bladder, barrel-shaped thickening of lower uterine segment, unable to remove placenta. CONCLUSIONS: Internal iliac artery balloon occlusion is an effective treatment for pernicious placenta previa.


Assuntos
Oclusão com Balão , Artéria Ilíaca , Placenta Prévia/terapia , Perda Sanguínea Cirúrgica , Transfusão de Sangue , Cesárea , Feminino , Humanos , Histerectomia , Gravidez , Estudos Retrospectivos
17.
Hum Brain Mapp ; 36(9): 3677-86, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26096541

RESUMO

Children exposed to natural disasters are vulnerable to the development of posttraumatic stress disorder (PTSD). Recent studies of other neuropsychiatric disorders have used graph-based theoretical analysis to investigate the topological properties of the functional brain connectome. However, little is known about this connectome in pediatric PTSD. Twenty-eight pediatric PTSD patients and 26 trauma-exposed non-PTSD patients were recruited from 4,200 screened subjects after the 2008 Sichuan earthquake to undergo a resting-state functional magnetic resonance imaging scan. Functional connectivity between 90 brain regions from the automated anatomical labeling atlas was established using partial correlation coefficients, and the whole-brain functional connectome was constructed by applying a threshold to the resultant 90 * 90 partial correlation matrix. Graph theory analysis was then used to examine the group-specific topological properties of the two functional connectomes. Both the PTSD and non-PTSD control groups exhibited "small-world" brain network topology. However, the functional connectome of the PTSD group showed a significant increase in the clustering coefficient and a normalized characteristic path length and local efficiency, suggesting a shift toward regular networks. Furthermore, the PTSD connectomes showed both enhanced nodal centralities, mainly in the default mode- and salience-related regions, and reduced nodal centralities, mainly in the central-executive network regions. The clustering coefficient and nodal efficiency of the left superior frontal gyrus were positively correlated with the Clinician-Administered PTSD Scale. These disrupted topological properties of the functional connectome help to clarify the pathogenesis of pediatric PTSD and could be potential biomarkers of brain abnormalities.


Assuntos
Encéfalo/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adolescente , Atlas como Assunto , Criança , Análise por Conglomerados , Conectoma/métodos , Terremotos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/fisiopatologia , Reconhecimento Automatizado de Padrão/métodos , Descanso , Transtornos de Estresse Pós-Traumáticos/etiologia
18.
Radiology ; 276(3): 818-27, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25848901

RESUMO

PURPOSE: To use resting-state functional magnetic resonance (MR) imaging and graph theory approaches to systematically investigate the topological organization of the functional connectome of patients with posttraumatic stress disorder (PTSD). MATERIALS AND METHODS: This study was approved by the research ethics committee, and all subjects provided informed consent for participation. Seventy-six patients with PTSD caused by an earthquake and 76 control subjects who experienced the same disaster were matched for age, sex, and years of education. The study subjects underwent resting-state functional MR imaging. The whole-brain functional network was then constructed by thresholding partial correlation matrices of 90 brain regions. The topological organization of the constructed network was analyzed by using graph theory approaches. Nonparametric permutation tests were also used for group comparisons of topological metrics. RESULTS: Compared with the control subjects, patients with PTSD exhibited abnormalities in global properties, including a significant decrease in path length (P = .0002) and increases in the clustering coefficient (P = .0014), global efficiency (P = .0002), and local efficiency (P = .0004). Locally, the patients with PTSD exhibited increased centrality in nodes that are predominately involved in the default-mode network (DMN) and the salience network (SN), including the posterior cingulate gyrus, the precuneus, the insula, the putamen, the pallidum, and the temporal regions. CONCLUSION: These results suggest that individuals with PTSD exhibit a shift toward "small-worldization" (in which the network transforms from a random or regular network to a small-world network) rather than toward randomization; furthermore, the disequilibrium between the DMN and the SN might be associated with the pathophysiology of PTSD.


Assuntos
Encéfalo/fisiopatologia , Conectoma , Imageamento por Ressonância Magnética , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Feminino , Humanos , Masculino
19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(5): 777-82, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26619556

RESUMO

UNLABELLED: [ABSTRACT] OBJECTIVE: To determine the value of low dose spiral CT scanning in diagnosing impacted teeth of children and adolescents. METHODS: A total of 153 children and adolescents with confirmed impacted teeth in West China Second University Hospital, Sichuan University were enrolled in this study. They were divided into 5 groups according to the different spiral CT scan parameters (tube current time product, scanning thickness and collimation value): Group A (n=30, 330 mAs, 6 X 0. 75 mm and 3. 0 mm), Group B (n=30, 140 mAs, 6 X 0. 75 mm and 3. 0 mm), Group C (n=30, 80 mAs, 6 X 0. 75 mm and 3. 0 mm), Group D (n=31, 80 mAs, 6 X 1. 50 mm and 5. 0 mm), and Group E (n=32, 50 mAs, 6 X 1. 50 mm and 5. 0 mm). There were no significant differences in general clinical features (P>0. 05) among the participants of the five groups. The phantoms were used to measure spatial resolution and contrast resolution of the scan images. Dose length product (DLP) was recorded during CT scanning for calculating effective dose (ED) of exposure. The quality of images was evaluated using a list of quality scoring criteria. RESULTS: (1) Under 330, 140, 80, 80 and 50 mAs, the images had a spatial resolution of 1.0 mm, with contrast resolution of 2. 0, 3. 0, 4. 5, 4. 5 and 6. 0 mm, respectively. (2) Significant differences in ED values were found among the five groups (F=1 064. 119, P=0. 000) and between every two of those groups (P<0. 05). Group E had the lowest ED (0. 19 mSv), 86. 52%, 67. 24%, 45. 71%, and 38. 71% lower than that in Group A, B, C and D, respectively (P<0. 05). (3) All of the five groups obtained an image quality score above 3, and no statistical differences appeared among the 5 groupl (F=1. 978, P>0. 05). The diagnostic results of the spiral CT were consistent with those of orthodontic surgery. CONCLUSION: Low dose spiral CT scanning can meet the image quality requirements for diagnosing impacted teeth, minimizing radiation exposure effectively.


Assuntos
Doses de Radiação , Tomografia Computadorizada Espiral , Dente Impactado/diagnóstico , Adolescente , Criança , China , Humanos
20.
Hum Brain Mapp ; 35(7): 2911-23, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24123412

RESUMO

Mild cognitive impairment (MCI) has received increasing attention not only because of its potential as a precursor for Alzheimer's disease but also as a predictor of conversion to other neurodegenerative diseases. Although MCI has been defined clinically, accurate and efficient diagnosis is still challenging. Although neuroimaging techniques hold promise, compared to commonly used biomarkers including amyloid plaques, tau protein levels and brain tissue atrophy, neuroimaging biomarkers are less well validated. In this article, we propose a connectomes-scale assessment of structural and functional connectivity in MCI via two independent multimodal DTI/fMRI datasets. We first used DTI-derived structural profiles to explore and tailor the most common and consistent landmarks, then applied them in a whole-brain functional connectivity analysis. The next step fused the results from two independent datasets together and resulted in a set of functional connectomes with the most differentiation power, hence named as "connectome signatures." Our results indicate that these "connectome signatures" have significantly high MCI-vs-controls classification accuracy, at more than 95%. Interestingly, through functional meta-analysis, we found that the majority of "connectome signatures" are mainly derived from the interactions among different functional networks, for example, cognition-perception and cognition-action domains, rather than from within a single network. Our work provides support for using functional "connectome signatures" as neuroimaging biomarkers of MCI.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/patologia , Disfunção Cognitiva/patologia , Conectoma , Vias Neurais/irrigação sanguínea , Vias Neurais/patologia , Idoso , Idoso de 80 Anos ou mais , Conjuntos de Dados como Assunto , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio , Máquina de Vetores de Suporte
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