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1.
Anticancer Res ; 44(5): 1845-1852, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677770

RESUMO

BACKGROUND/AIM: Matrix metalloproteinase-9 (MMP-9) expression is upregulated in various diseases, including lung cancer. However, the role of MMP-9 genotype in lung cancer susceptibility remains uncertain. This study aimed to clarify the contribution of MMP-9 promoter rs3918242 genotypes to the risk of lung cancer in Taiwan. MATERIALS AND METHODS: The MMP-9 rs3918242 genotypes of 358 lung cancer patients and 716 healthy controls were determined using polymerase chain reaction-restriction fragment length polymorphism methodology. RESULTS: Individuals carrying the variant CT or TT genotype of MMP-9 rs3918242 did not demonstrate an increased risk of lung cancer compared to wild-type CC carriers [odds ratio (OR)=1.11 and 1.85, 95% confidence interval (95%CI)=0.82-1.48 and 0.91-3.76; p=0.5541 and 0.1280, respectively]. Moreover, individuals carrying the T allele did not show a higher lung cancer risk compared to those with the C allele (OR=1.21, 95%CI=0.95-1.54, p=0.1444). However, a significant association was observed between the MMP-9 rs3918242 TT genotype and lung cancer risk among non-smokers (OR=5.48, 95%CI=1.31-22.89, p=0.0181). CONCLUSION: The presence of the TT genotype for MMP-9 rs3918242 may indicate an elevated risk of lung cancer among non-smokers.


Assuntos
Predisposição Genética para Doença , Genótipo , Neoplasias Pulmonares , Metaloproteinase 9 da Matriz , Polimorfismo de Nucleotídeo Único , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/epidemiologia , Metaloproteinase 9 da Matriz/genética , Masculino , Taiwan/epidemiologia , Feminino , Pessoa de Meia-Idade , Estudos de Casos e Controles , Idoso , Fatores de Risco , Regiões Promotoras Genéticas , Alelos
2.
Brain Sci ; 13(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36672073

RESUMO

Mild cognitive impairment (MCI) is widely regarded to be the intermediate stage to Alzheimer's disease. Cerebral morphological alteration in cortical subregions can provide an accurate predictor for early recognition of MCI. Thirty patients with MCI and thirty healthy control subjects participated in this study. The Desikan-Killiany cortical atlas was applied to segment participants' cerebral cortex into 68 subregions. A complexity measure termed fractal dimension (FD) was applied to assess morphological changes in cortical subregions of participants. The MCI group revealed significantly decreased FD values in the bilateral temporal lobes, right parietal lobe including the medial temporal, fusiform, para hippocampal, and also the orbitofrontal lobes. We further proposed a novel FD-based brain structural network to compare network parameters, including intra- and inter-lobular connectivity between groups. The control group had five modules, and the MCI group had six modules in their brain networks. The MCI group demonstrated shrinkage of modular sizes with fewer components integrated, and significantly decreased global modularity in the brain network. The MCI group had lower intra- and inter-lobular connectivity in all lobes. Between cerebral lobes, the MCI patients may maintain nodal connections between both hemispheres to reduce connectivity loss in the lateral hemispheres. The method and results presented in this study could be a suitable tool for early detection of MCI.

3.
In Vivo ; 36(2): 603-609, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35241512

RESUMO

BACKGROUND/AIM: Gadolinium has been reported to cause liver lobular necrosis and nephrogenic systemic fibrosis. However, its toxicity to the skin remains unknown. This study aimed to investigate the effect of a high dose of gadolinium-based contrast agent gadodiamide on the human keratinocyte HaCaT cell line. MATERIALS AND METHODS: Cell viability was assessed using MTT assay, and autophagy was assessed using acridine orange and LysoTracker Red staining. Western blotting was performed to verify the changes in Bcl2 and Bax levels. RESULTS: The viability of HaCaT cells was significantly suppressed after gadodiamide treatment. Interestingly, gadodiamide caused autophagic vacuoles, whereas the autophagy inhibitors 3-methyladenine and chloroquine significantly alleviated autophagic cell death. Simultaneously, gadodiamide induced apoptosis, which was reduced by caspase inhibitors. Gadodiamide also inhibited Bcl-2 expression and promoted Bax expression. CONCLUSION: Gadodiamide induced both autophagy and apoptosis in HaCaT cells. Physicians should carefully assess the gadodiamide dosage used clinically.


Assuntos
Apoptose , Gadolínio DTPA , Autofagia , Gadolínio DTPA/farmacologia , Humanos , Queratinócitos
4.
In Vivo ; 35(6): 3221-3232, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34697153

RESUMO

BACKGROUND/AIM: The use of iodinated contrast media may impair renal function. However, no report has addressed the nephrotoxicity of high doses of iodinated contrast media in normal kidney cells and its associated molecular mechanisms. MATERIALS AND METHODS: Cell proliferation was assessed using the MTT assay. Cell death was evaluated through examining the morphological changes and TUNEL assay. Autophagy was detected through acridine orange staining and lysotracker staining. Reactive oxygen species production and AKT kinase activity were examined. RESULTS: Iopromide induced cell death and triggered apoptosis and autophagy in HEK 293 cells. Cell viability was significantly restored in the presence of a pan-caspase inhibitor or a ROS scavenger, N-acetyl-L-cysteine. AKT kinase activity was found to be reduced in iopromide-treated HEK 293 cells. CONCLUSION: High concentrations of iopromide induce cell damage, apoptosis, and autophagy through down-regulating AKT and ROS-activated cellular stress pathways in HEK 293 cells.


Assuntos
Apoptose , Autofagia , Linhagem Celular Tumoral , Células HEK293 , Humanos , Iohexol/análogos & derivados , Rim/fisiologia , Espécies Reativas de Oxigênio
5.
In Vivo ; 35(5): 2621-2630, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410949

RESUMO

BACKGROUND/AIM: Magnetic resonance imaging (MRI) is a technique for evaluating patients with primary and metastatic tumors. The contrast agents improve the diagnostic accuracy of MRI. Large quantities of a contrast agent must be administrated into the patient to obtain useful images, which leads to cell injury. Gadolinium has been reported to cause central lobular necrosis of the liver and nephrogenic systemic fibrosis. However, the toxicity caused on brain tissue is uncertain. MATERIALS AND METHODS: This study mainly aimed on the in vitro study of high concentration (2 and 5-fold of normal concentration) gadolinium-based contrast agents (GBCAs), gadodiamide (Omniscan®), on normal brain glial SVG P12 cells. MTT assay, DAPI staining, immunofluorescent staining, LysoTracker Red staining, and western blotting analysis were applied on the cells. RESULTS: The viability of gadodiamide (1.3, 2.6, 5.2, 13 and 26 mM)-treated SVG P12 cells was significantly reduced after 24 h of incubation. Gadodiamide caused significant autophagic flux at 2.6, 5.2 and 13.0 mM as seen by acridine orange (AO) staining, LC-3-GFP and LysoTracker Red staining. The expression levels of autophagy-related proteins such as beclin-1, ATG-5, ATG-14 and LC-3 II were up-regulated after 24 h of gadodiamide incubation. Autophagy inhibitors including 3-methyladenine (3-MA), chloroquine (CQ) and bafilomycin A1 (Baf) significantly alleviated the autophagic cell death effect of gadodiamide on normal brain glial SVG P12 cells. Gadodiamide induced significant apoptotic effects at 5.2 mM and 13.0 mM as seen by DAPI staining and the pan-caspase inhibitor significantly alleviated the apoptotic effect. Gadodiamide at 5.2 mM and 13.0 mM inhibited antiapoptotic protein expression levels of Bcl-2 and Bcl-XL, while promoted pro-apoptotic protein expression levels of Bax, BAD, cytochrome c, Apaf-1, cleaved-caspase-9 and cleaved-caspase-3. CONCLUSION: Normal brain glial SVG P12 cells treated with high concentrations of gadodiamide can undergo autophagy and apoptosis.


Assuntos
Proteínas Reguladoras de Apoptose , Gadolínio DTPA , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Encéfalo/metabolismo , Gadolínio DTPA/toxicidade , Humanos
6.
Brain Sci ; 11(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466961

RESUMO

Normal aging is associated with functional and structural alterations in the human brain. The effects of normal aging and gender on morphological changes in specific regions of the brain are unknown. The fractal dimension (FD) can be a quantitative measure of cerebral folding. In this study, we used 3D-FD analysis with the Desikan-Killiany (DK) atlas to assess subregional morphological changes in adulthood. A total of 258 participants (112 women and 146 men) aged 30-85 years participated in this study. Participants in the middle-age group exhibited a decreased FD in the lateral frontal lobes, which then spread to the temporal and parietal lobes. Men exhibited an earlier and more significant decrease in FD values, mainly in the right frontal and left parietal lobes. Men exhibited more of a decrease in FD values in the subregions on the left than those in the right, whereas women exhibited more of a decrease in the lateral subregions. Older men were at a higher risk of developing mild cognitive impairment (MCI) and exhibited age-related memory decline earlier than women. Our FD analysis using the DK atlas-based prediagnosis may provide a suitable tool for assessing normal aging and neurodegeneration between groups or in individual patients.

7.
Entropy (Basel) ; 22(8)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-33286597

RESUMO

The morphological changes in cortical parcellated regions during aging and whether these atrophies may cause brain structural network intra- and inter-lobe connectivity alterations are subjects that have been minimally explored. In this study, a novel fractal dimension-based structural network was proposed to measure atrophy of 68 parcellated cortical regions. Alterations of structural network parameters, including intra- and inter-lobe connectivity, were detected in a middle-aged group (30-45 years old) and an elderly group (50-65 years old). The elderly group exhibited significant lateralized atrophy in the left hemisphere, and most of these fractal dimension atrophied regions were included in the regions of the "last-in, first-out" model. Globally, the elderly group had lower modularity values, smaller component size modules, and fewer bilateral association fibers. They had lower intra-lobe connectivity in the frontal and parietal lobes, but higher intra-lobe connectivity in the temporal and occipital lobes. Both groups exhibited similar inter-lobe connecting pattern. The elderly group revealed separations, sparser long association fibers, commissural fibers, and lateral inter-lobe connectivity lost effect, mainly in the right hemisphere. New wiring and reconfiguring modules may have occurred within the brain structural network to compensate for connectivity, decreasing and preventing functional loss in cerebral intra- and inter-lobe connectivity.

8.
Oncol Rep ; 41(2): 1324-1332, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30535448

RESUMO

Gadolinium (Gd) compounds serve as magnetic resonance imaging contrast agents and exert certain anticancer activities. Yet, the molecular signaling underlying the antitumor effect of Gd chloride (GdCl3) on glioma remains unclear. In the present study, we aimed to ascertain the apoptotic mechanisms of GdCl3 on rat glioma C6 cells. Our results demonstrated that GdCl3 significantly reduced cell viability and shrunk cell morphology of C6 cells in a concentration­dependent manner. GdCl3 led to apoptotic C6 cell death as detected by TUNEL staining. An increase in cleaved caspase­3, cleaved caspase­8 and cleaved caspase­9 occurred in GdCl3­treated C6 cells as detected by immunoblotting analysis. The activities of caspase­3, caspase­8 and caspase­9 were increased, and the specific inhibitors of caspase­3/­8/­9 individually reversed cell viability, which caused apoptotic death in C6 cells prior to GdCl3 exposure. GdCl3 also caused an elevation in the cytoplasmic Ca2+ level and reactive oxygen species (ROS) production, as well as the loss of mitochondrial membrane potential (ΔΨm) as shown by flow cytometric analysis in C6 cells. The results from the immunoblotting analysis demonstrated that there were upregulated protein levels of cytochrome c and Bax but a downregulated protein level of Bcl­2 in C6 cells after GdCl3 treatment. Additionally, GdCl3 decreased the protein levels of phosphorylated­extracellular signal­regulated kinases, phosphorylated­c­Jun N­terminal kinase and phosphorylated­p38 mitogen­activated protein kinases in C6 cells. In conclusion, ROS production and MAPKs signaling pathways contribute to GdCl3­induced caspase cascade­mediated apoptosis in C6 cells. Our findings provide a better understanding of the molecular mechanisms underlying the role of GdCl3 in rat glioma C6 cells.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/enzimologia , Caspases/metabolismo , Gadolínio/farmacologia , Glioma/enzimologia , Sistema de Sinalização das MAP Quinases , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose , Neoplasias Encefálicas/patologia , Glioma/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ratos , Transdução de Sinais
9.
In Vivo ; 32(3): 677-684, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29695578

RESUMO

BACKGROUND/AIM: Gadoxetate disodium (Primovist or Eovist) is extensively used as a hepatospecific contrast agent during magnetic resonance imaging (MRI) examinations. However, there is no information determining whether gadoxetate disodium has a cytotoxic impact and/or affects relative gene expression on liver cells. In the current study, we investigated the effects of gadoxetate disodium on cytotoxicity and the levels of gene expression in human normal Chang Liver cells. MATERIALS AND METHODS: The cytotoxic effect was detected via methyl thiazolyl tetrazolium (MTT) assay and 4',6-diamidino-2-phenylindole (DAPI) staining. mRNA expression was monitored by cDNA microarray and quantitative PCR (qPCR) analysis. The protein levels were determined by western blotting. RESULTS: Gadoxetate disodium at 5 and 10 mM failed to induce any cell cytotoxicity and morphological changes in Chang Liver cells. Our data demonstrated that gadoxetate disodium significantly enhanced the expression of 29 genes and suppressed that of 27. The SLCO1C1 (solute carrier organic anion transporter family member 1C1) mRNA expression was also increased by 2.62-fold (p-value=0.0006) in gadoxetate disodium-treated cells. Furthermore, we also checked and found that gadoxetate disodium up-regulated organic anion transporter polypeptide 1B1 (OATP1B1) protein level and increased OATP uptake transporter gene SLCO1C1 mRNA expression. CONCLUSION: Our results provide evidence regarding that gadoxetate disodium might be no cytotoxic effects on liver cells.


Assuntos
Meios de Contraste/farmacologia , Gadolínio DTPA/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Fígado/diagnóstico por imagem , Fígado/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional/métodos , Meios de Contraste/química , Gadolínio DTPA/química , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Imageamento por Ressonância Magnética/métodos , Transcriptoma
10.
Biomedicine (Taipei) ; 8(1): 1, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29480796

RESUMO

Iodinated contrast media (iodinated CM) have increased ability to absorb x-rays and to visualize structures that normally are impossible to observe in a radiological examination. The use of iodinated CM may destory renal function, commonly known as contrast-induced nephropathy (CIN), which can result in acute renal failure (ARF). This review article mainly focuses on the following areas: (1) classifications of iodinated CM: ionic or non-ionic, high-osmolarity contrast media (HOCM), low-osmolarity contrast media (LOCM) and iso-osmolarity contrast media (IOCM); (2) an introduction to the physical and chemical properties of the non-ionic iodinated CM; (3) the management of anaphylactic reaction by iodinated CM; (4) a suggested single injection of adult doses and maximum dose for non-ionic iodinated CM; (5) the molecular mechanism of contrast-induced nephropathy (CIN); (6) In vitro studies on iodinated CM. Based on above information, this review article provide an insight for understanding the drug safety of iodinated CM.

11.
J Clin Ultrasound ; 46(5): 361-363, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29159809

RESUMO

Synovial chondromatosis is a rare, benign, proliferative cartilaginous lesion arising from the synovial tissue, tenosynovium, or bursal lining. We describe the case of a patient who initially presented with multiple axillary masses. Breast ultrasound (US) was requested due to the concern of a breast tumor with axillary lymph node metastases. US study was helpful and provided adequate information to suggest the diagnosis.


Assuntos
Condromatose Sinovial/complicações , Condromatose Sinovial/diagnóstico por imagem , Doenças Linfáticas/diagnóstico por imagem , Doenças Linfáticas/etiologia , Articulação do Ombro/diagnóstico por imagem , Axila/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Pessoa de Meia-Idade , Ultrassonografia
12.
J Med Biol Eng ; 37(2): 181-190, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29930493

RESUMO

Sintered dicalcium pyrophosphate (SDCP), a synthetic pyrophosphate analog, has shown potential for the management of osteoporosis. The long-term oral toxicity and anti-osteoporotic effect of SDCP in a postmenopausal osteoporosis rat model were evaluated in this study. SDCP was orally administered to bilateral ovariectomized (OVX) Wistar rats at a dose of 0.75 mg/kg daily for 24 weeks following by 2 weeks of observation. There were no abnormal findings in clinical signs of toxicity, food consumption, body weight, blood examination, necropsy, and histological inspection attributable to the ingestion of SDCP. The serum level of type I collagen fragments, a bone resorption marker, decreased in SDCP-treated rats, and the bone formation markers alkaline phosphatase, osteocalcin, and osteopontin significantly decreased. These findings indicate that the bone turnover rate decreased in SDCP-treated animals. Relative to OVX rats, the increase in serum tartrate-resistant acid phosphatase 5b level represents an increase in bony tissues in the SDCP-treated rats. Histological examinations of distal femoral metaphyses further revealed that the ingestion of SDCP improved the trabecular bone architecture and decreased bone porosity. Analysis of limb bone ashes showed a significant increase in bone mineral content. Our results show that SDCP inhibits bone resorption to restore bone mass in OVX rats without deleterious effects, and therefore that SDCP has potential in the management of osteoporosis.

13.
Oncol Rep ; 36(6): 3421-3426, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27748868

RESUMO

Gadolinium (Gd) compounds are important as magnetic resonance imaging (MRI) contrast agents, and are potential anticancer agents. However, no report has shown the effect of gadolinium chloride (GdCl3) on osteosarcoma in vitro. The present study investigated the apoptotic mechanism of GdCl3 on human osteosarcoma U-2 OS cells. Our results indicated that GdCl3 significantly reduced cell viability of U-2 OS cells in a concentration-dependent manner. GdCl3 led to apoptotic cell shrinkage and DNA fragmentation in U-2 OS cells as revealed by morphologic changes and TUNEL staining. Colorimetric assay analyses also showed that activities of caspase-3, caspase-8, caspase-9 and caspase-4 occurred in GdCl3-treated U-2 OS cells. Pretreatment of cells with pan-caspase inhibitor (Z-VAD-FMK) and specific inhibitors of caspase-3/-8/-9 significantly reduced cell death caused by GdCl3. The increase of cytoplasmic Ca2+ level, ROS production and the decrease of mitochondria membrane potential (ΔΨm) were observed by flow cytometric analysis in U-2 OS cells after GdCl3 exposure. Western blot analyses demonstrated that the levels of Fas, FasL, cytochrome c, Apaf-1, GADD153 and GRP78 were upregulated in GdCl3-treated U-2 OS cells. In conclusion, death receptor, mitochondria-dependent and endoplasmic reticulum (ER) stress pathways contribute to GdCl3-induced apoptosis in U-2 OS cells. GdCl3 might have potential to be used in treatment of osteosarcoma patients.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Gadolínio/farmacologia , Osteossarcoma/tratamento farmacológico , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Chaperona BiP do Retículo Endoplasmático , Humanos , Potencial da Membrana Mitocondrial , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
J Craniomaxillofac Surg ; 44(9): 1333-41, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27527677

RESUMO

PURPOSE: Biodegradable polymer fixators have been used widely in oral and maxillofacial surgery for fracture management. However, short-comings such as insufficient mechanical strength, inappropriate degradation time, lack of radiolucency, and foreign body reactions during bone remodeling remain. MATERIAL AND METHODS: In this study, calcium phosphate ceramic (CPC, including tricalcium phosphate [TCP] and tetracalcium phosphate/dicalcium phosphate [TTCP/DCP]) and poly(ε-caprolactone) (PCL) were used to fabricate biodegradable orthopedic fixation devices. RESULTS: Different weight ratios of CPC were added to PCL, and the results showed that the PCL/CPC composites had good radiopacity, mechanical properties, and biocompatibility. CPC was transformed into hydroxyapatite when the composites were immersed in simulated body fluid. The PCL/TTCP/DCP composite had a higher compressive strength relative to PCL/TCP after setting, and this self-reinforcing property contributed to the hydration of TTCP/DCP and formation of apatite crystals. Thus, PCL/TTCP/DCP screws were prepared for animal studies. No postoperative mortality or complications were noted 6 months postsurgery. Biodegradation of the PCL/TTCP/DCP screws and newly formed bony tissue around the degraded composites were shown on both micro-computed tomography and histology. No peri-implant bone resorption was noted. CONCLUSION: The self-reinforcing PCL/TTCP/DCP composite can be used to fabricate biodegradable fixators for fracture management in craniomaxillofacial fracture fixation.


Assuntos
Implantes Absorvíveis , Fosfatos de Cálcio/farmacologia , Poliésteres/farmacologia , Fraturas Cranianas/cirurgia , Animais , Materiais Biocompatíveis/farmacologia , Parafusos Ósseos , Força Compressiva , Modelos Animais de Doenças , Fêmur/cirurgia , Concentração de Íons de Hidrogênio , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Coelhos , Propriedades de Superfície , Difração de Raios X
15.
Biomed Mater ; 11(2): 025012, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27041468

RESUMO

Internal fixation devices, which can stabilize and realign fractured bone, are widely used in fracture management. In this paper, a biodegradable composite fixator, composed of poly(ε-caprolactone), calcium phosphate ceramic and calcium sulfate (PCL/CPC/CS), is developed. The composition of CS, which has a high dissolution rate, was expected to create a porous structure to improve osteofixation to the composite fixator. PCL, PCL/CPC, and PCL/CPC/CS samples were prepared and their physical properties were characterized in vitro. In vivo performance of the composite screws was verified in the distal femurs of rabbits. Results showed that the PCL/CPC/CS composite had a higher compressive strength (28.55 ± 3.32 MPa) in comparison with that of PCL (20.64 ± 1.81 MPa) (p < 0.05). A larger amount of apatite was formed on PCL/CPC/CS than on PCL/CPC, while no apatite was found on PCL after simulated body fluid immersion. In addition, PCL/CPC/CS composites also had a faster in vitro degradation rate (13.05 ± 3.42% in weight loss) relative to PCL (1.79 ± 0.23%) and PCL/CPC (4.32 ± 2.18%) (p < 0.001). In animal studies, PCL/CPC/CS screws showed a greater volume loss than that of PCL or PCL/CPC at 24 weeks post-implantation. Under micro-computerized tomography observation, animals with PCL/CPC/CS implants had better osseointegration in terms of the structural parameters of the distal metaphysis, including trabecular number, trabecular spacing, and connectivity density, than the PCL screw. This study reveals that the addition of CS accelerates the biodegradation and enhanced apatite formation of the PCL/CPC composite screw. This osteoconductive PCL/CPC/CS is a good candidate material for internal fixation devices.


Assuntos
Parafusos Ósseos , Cerâmica , Fixação Interna de Fraturas/instrumentação , Implantes Absorvíveis , Animais , Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Sulfato de Cálcio/química , Cerâmica/química , Força Compressiva , Feminino , Teste de Materiais , Camundongos , Células NIH 3T3 , Osseointegração , Poliésteres/química , Coelhos , Microtomografia por Raio-X
17.
Iran J Radiol ; 10(3): 172-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24348606

RESUMO

The current mainstay of treatment in spontaneous intracranial hypotension (SIH) is an epidural blood patch (EBP). Although magnetic resonance imaging (MRI) has a well-established role in the diagnosis of SIH, imaging features regarding the treatment efficacy of EBP have rarely been discussed. We therefore sought to investigate and compare the sequential brain MRI studies before and after EBP by evaluating the changes of the following intracranial structures-the contour of the transverse dural sinus (TDS), tension of the pituitary stalk (or the infundibulum), and thickness of the dura mater. We found that the progressive reversals of these structures are predictive of an effective EBP.

18.
Neuroimage ; 59(2): 1098-105, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-21967726

RESUMO

This study investigated whether diffusion tensor imaging (DTI) could identify potential abnormalities in type 2 diabetes mellitus (T2DM) patients without cognitive complaints compared to healthy controls. In addition, the existence of associations between diffusion measures and clinical parameters was examined. Forty T2DM patients and 97 non-diabetic controls completed a clinical and biochemistry examination. Structural MRI scans (DTI, T1, T2, FLAIR) were subsequently acquired with a 1.5 Tesla scanner. In addition to a global DTI analysis, voxel-based analysis was performed on the fractional anisotropy (FA), mean diffusivity (MD), and axial (AD) and transverse (TD) diffusivity maps to investigate regions that exhibit (i) WM differences between patients and controls; and (ii) associations between clinical measurements and these DTI indices. There were no significant differences in age, gender, and WM hyperintensity scores derived by the conventional MRI scans between controls and T2DM patients. For the T2DM patients, however, the MD of the brain parenchyma was significantly increased compared to controls and was positively correlated with disease duration. The voxel based analyses revealed (i) a significantly decreased FA in the bilateral frontal WM compared to controls which was mainly caused by an increased TD and not a decreased AD within these regions; (ii) a significant association between disease duration and microstructural properties in several brain regions including bilateral cerebellum, temporal lobe WM, right caudate, bilateral cingulate gyrus, pons, and parahippocampal gyrus. Our findings indicate that microstructural WM abnormalities and associations with clinical measurements can be detected with DTI in T2DM patients.


Assuntos
Encéfalo/patologia , Diabetes Mellitus Tipo 2/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Fibras Nervosas Mielinizadas/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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