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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 51(1): 53-7, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-26792189

RESUMO

IgG4-related disease is a novel clinical entity which can affect single or multiple organs. IgG4-related sialadenitis is referred to the salivary gland involvement of IgG4-related disease, with or without other organ involvement. IgG4-related sialadenitis is characterized by painless swelling or enlargement of salivary glands, high serum IgG4 level, abundant IgG4+ plasma cells infiltration with fibrosis histologically, and good response to glucocorticoids. With review of related articles, highlight and provide an overview of the most recent and focused findings and concepts of this disease, including the most significant pathogenic process based on kinds of immunocytes, cytokines, as well as participation of epithelial-mesenchymal transition, the clinical value of elevated serum IgG4 concentration and pathological role of infiltrated IgG4+ plasma cells, the potential relationship with salivary gland malignant tumor, the applying and usefulness of positron emission tomography-CT, the diagnostic utility of lip biopsy, treatment, prognosis, and also future perspectives.


Assuntos
Imunoglobulina G/sangue , Sialadenite/sangue , Biópsia , Glucocorticoides/uso terapêutico , Humanos , Paraproteinemias , Tomografia por Emissão de Pósitrons , Prognóstico , Neoplasias das Glândulas Salivares/sangue , Glândulas Salivares/imunologia , Sialadenite/tratamento farmacológico , Sialadenite/imunologia
2.
J Anim Physiol Anim Nutr (Berl) ; 98(2): 310-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23718228

RESUMO

The objective of this study was to investigate the regulatory mechanism underlying the increased muscle protein accumulation in pigs while were fed a high protein diet. The eukaryotic initiation factors (eIFs) have been reported to involve in muscle protein synthesis. We investigated the mRNA and protein expression levels of eIF2B1, 4A1, 4B and 4E in Wujin pigs fed either a high protein (HP: 18%) or a low protein (LP: 14%) diet at 30, 60 or 100 kg body weight, based on real-time PCR and western blotting analyses. Our results indicated that the expression levels of eIF2B1 mRNA and protein were increased by HP diet at all body weight. The HP diet showed higher mRNA and protein levels of eIF4B gene at 60 and 100 kg. The protein expression of eIF4E phosphorylation was increased by HP diet only at 30 kg. These data suggested that the HP diet promoted porcine muscle protein accumulation mainly by up-regulating eIF2B1, 4B and 4E rather than 4A1 expression along the growth stages.


Assuntos
Proteínas Alimentares/farmacologia , Fatores de Iniciação em Eucariotos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Músculo Esquelético/metabolismo , Suínos/metabolismo , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fatores de Iniciação em Eucariotos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Suínos/genética
3.
Res Vet Sci ; 93(3): 1190-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22795880

RESUMO

Intramuscular fat (IMF) content plays an important role in meat quality. Triglyceride (TG) metabolism in intramuscular adipocytes is strongly associated with the intramuscular fat deposition. To better understand the mechanisms leading to IMF deposition we compared the expression levels of genes related to preadipocyte differentiation and lipogenesis in the intramuscular preadipocytes isolated from the longissimus muscle of Wujin and Landrace pigs. The results showed that the intramuscular preadipocytes could differentiate into mature adipocytes in vitro. Triglyceride content in adipocytes isolated from Wujin pigs was higher than Landrace pigs during the middle and later phases of preadipocyte differentiation. The expression levels of genes related to preadipocyte differentiation such as PPARG and CEBPA showed differential expression between Wujin and Landrace porcine adipocytes during the early stage of differentiation. The expression levels of lipogenic genes such as FASN and SREBF1 were significantly higher in Wujin porcine intramuscular preadipocytes than in Landrace intramuscular preadipocytes at the middle and the later stages of differentiation. This suggests that preadipocyte differentiation and lipogenesis exhibited breed-related scheduling.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Lipogênese/fisiologia , Músculo Esquelético/citologia , Suínos/metabolismo , Animais , Diferenciação Celular , Regulação da Expressão Gênica/fisiologia , Metabolismo dos Lipídeos/genética , Lipogênese/genética , Músculo Esquelético/metabolismo
4.
Mol Biol Rep ; 39(5): 5767-74, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22212709

RESUMO

Three novel ovine genes were obtained from muscle full-length cDNA library of black-boned sheep. Sequence analysis revealed that nucleotide sequences of these genes were not homologous to any of the known sheep or goat genes, but these genes have high similarity to ATP synthase subunit O (ATP5O), NADH dehydrogenase (ubiquinone) 1 alpha subcomplex, 12 (NDUFA12) and ubiquinol-cytochrome c reductase hinge protein (UQCRH) genes of other mammal animals (accession number: FJ546085, FJ546078 and FJ546083). The alignment analysis showed that the ovine ATP5O, NDUFA12 and UQCRH genes and proteins have closer genetic relationships with the ATP5O, NDUFA12 and UQCRH genes and proteins from cattle. Conserved domain prediction showed that these three genes included OSCP, NDUFA12 superfamily and UCR-hinge superfamily domains respectively. The deduced sequence of ATP5O, NDUFA12 and UQCRH protein had 213, 145 and 91 amino acid residues, with a molecular weight of approximately 23419.66, 17089.50 and 10657.75 Da and a theoretical isoelectric point of 9.90, 9.68 and 4.45. The secondary structure prediction revealed that 60% helix structure in ATP5O, 60% coils in NDUFA12 and no strand in UQCRH. One potential signal peptide structure in ATP5O protein were found. NDUFA12 and UQCRH have the extremely low possibility of signal peptides. Meanwhile, RasMol was used for visualizing the PDB files generated by Swiss-Model in cartoon or three-dimensional format. ATP5O and UQCRH protein were modeled by Swiss-Model. Tissue expression profile indicated that the ovine ATP5O, NDUFA12 and UQCRH genes could be expressed in all detected tissues including muscles, heart, liver, spleen, lung, kidney and adipose tissues, but the expression abundance of these genes were various in the different tissues. Our experiment supplied the primary foundation for further researches on these three ovine genes.


Assuntos
Complexo III da Cadeia de Transporte de Elétrons/genética , Perfilação da Expressão Gênica , Biblioteca Gênica , Proteínas Mitocondriais/genética , ATPases Mitocondriais Próton-Translocadoras/genética , Músculos/metabolismo , Ovinos/genética , Sequência de Aminoácidos , Animais , Osso e Ossos , Sequência Conservada/genética , Complexo III da Cadeia de Transporte de Elétrons/química , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica , Interações Hidrofóbicas e Hidrofílicas , Ponto Isoelétrico , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , ATPases Mitocondriais Próton-Translocadoras/química , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Sinais Direcionadores de Proteínas/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Análise de Sequência de DNA , Homologia Estrutural de Proteína
5.
AJNR Am J Neuroradiol ; 33(5): 910-4, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22282449

RESUMO

BACKGROUND AND PURPOSE: SWI is a high-resolution 3D, fully velocity-compensated gradient-echo sequence that uses both magnitude and phase data. The purpose of this study was to investigate the phase behavior of the capsule of pyogenic brain abscesses with noncontrast SWI. MATERIALS AND METHODS: Fourteen patients with pyogenic brain abscesses were studied at 1.5T. In all of the patients, SWI images were obtained and reviewed in addition to conventional MR images. Phase values within the abscess capsule were measured and compared with those from the abscess cavities and contralateral normal white matter using 1-way repeated measures ANOVA with post hoc Bonferroni analysis. RESULTS: SWI phase images showed mild hypointesity in 6 patients, isointensity in 3 patients, and mixed iso- to mild hypointensity in 5 patients. The means of phase in the cavity, rim of abscesses, and contralateral normal white matter were -7.552 × 10(-3) ± 0.024, -0.105 ± 0.080, and +0.029 ± 0.011 radians, respectively. Post hoc comparisons showed significant differences between any pair of the 3 regions (abscess cavity, rim capsule, and normal white matter) in SWI (all Ps < .005). CONCLUSIONS: SWI phase imaging shows evidence of paramagnetic substances in agreement with the presence of free radicals from phagocytosis. SWI may provide additional information valuable in the characterization of pyogenic brain abscesses.


Assuntos
Algoritmos , Abscesso Encefálico/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-23365910

RESUMO

The aim of this study was to evaluate the effect of contrast agent gadobutrol on the magnetic resonance diffusion-weighted imaging (MR DWI). Gadobutrol has higher relaxivity than Gd-DTPA and it also has higher formulation 1.0 M than Gd-DTPA 0.5 M. VX2 tumor implanted on the left thigh of each New Zealand rabbit was used as the animal model. The MR scanning was performed using a 1.5 T clinical whole-body MR scanner with an 8-channel knee coil. The results showed that there were significant differences in the signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) values between tumor and muscle both before and after gadobutrol injection (0.1 mmol/kg). However, there were no significant differences in the SNR and ADC values of tumor or muscle before and after gadobutol administration. There were also no significant difference in the contrast-to-noise ratio (CNR) values of tumor and muscle before and after gadobutrol injection.


Assuntos
Meios de Contraste/farmacologia , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Compostos Organometálicos/farmacologia , Razão Sinal-Ruído , Animais , Músculo Esquelético/diagnóstico por imagem , Coelhos , Radiografia
7.
J Biomed Mater Res B Appl Biomater ; 96(1): 76-83, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21053263

RESUMO

Poly (methyl methacrylate) (PMMA) bone cement is widely used in vertebral body augmentation procedures such as vertebroplasty and balloon kyphoplasty. Filling high modulus PMMA increases the modulus of filled verterbra, increasing the risk of fracture in the adjacent vertebra. On the other hand, in porous PMMA bone cements, wear particle generation and deterioration of mechanical performance are the major drawbacks. This study adopts a new approach by utilizing linoleic acid coated strontium substituted hydroxyapatite nanoparticle (Sr-5 HA) and linoleic acid as plasticizer reducing bone cement's modulus with minimal impact on its strength. We determined the compressive strength (UCS) and modulus (Ec), hydrophobicity, injectability, in vitro bioactivity and biocompatibility of this bone cement at different filler and linoleic acid loading. At 20 wt % Sr5-HA incorporation, UCS and Ec were reduced from 63 ± 2 MPa, 2142 ± 129 MPa to 58 ± 2 MPa, 1785 ± 64 MPa, respectively. UCS and Ec were further reduced to 49 ± 2 MPa and 774 ± 70 MPa respectively when 15 v/v of linoleic acid was incorporated. After 7 days of incubation, pre-osteoblast cells (MC3T3-E1) attached on 20 wt % Sr5-HA and 20 wt % Sr5-HA with 15 v/v of linoleic acid group were higher (3.73 ± 0.01 x 104, 2.27 ± 0.02 x 104) than their PMMA counterpart (1.83 ± 0.04 x 104). Incorporation of Sr5-HA with linoleic acid in monomer phase is more effective in reducing the bone cement's stiffness than Sr5-HA alone. Combination of low stiffness and high mechanical strength gives the novel bone cement the potential for use in vertebroplasty cement applications.


Assuntos
Cimentos Ósseos/química , Substitutos Ósseos/química , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Ácido Linoleico/química , Polimetil Metacrilato/química , Estrôncio/química , Animais , Linhagem Celular , Humanos , Teste de Materiais/métodos , Camundongos , Nanopartículas/química
8.
J R Soc Interface ; 7(48): 1025-31, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20031984

RESUMO

Boron plays important roles in many life processes including embryogenesis, bone growth and maintenance, immune function and psychomotor skills. Thus, the delivery of boron by the degradation of borate glass is of special interest in biomedical applications. However, the cytotoxicity of borate glass which arises with the rapid release of boron has to be carefully considered. In this study, it was found that the incorporation of strontium into borate glass can not only moderate the rapid release of boron, but also induce the adhesion of osteoblast-like cells, SaOS-2, thus significantly increasing the cyto-compatibility of borate glass. The formation of multilayers of apatite with porous structure indicates that complete degradation is optimistic, and the spread of SaOS-2 covered by apatite to form a sandwich structure may induce bone-like tissue formation at earlier stages. Therefore, such novel strontium-incorporated borosilicate may act as a new generation of biomaterial for bone regeneration, which not only renders boron as a nutritious element for bone health, but also delivers strontium to stimulate formation of new bones.


Assuntos
Vidro/química , Apatitas , Materiais Biocompatíveis/química , Regeneração Óssea , Osso e Ossos , Boratos , Boro , Humanos , Osteoblastos , Osteogênese , Porosidade , Estrôncio
9.
Caries Res ; 43(4): 322-30, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19556792

RESUMO

Octacalcium phosphate (OCP) is of considerable importance as a precursor in the formation of dental enamel and an intermediate phase in the precipitation of hydroxyapatite (HAp) in bone. However, agreement is poor on the solubility product (pK(sp)), possibly due to the formation of the more stable phase HAp. The system was investigated using solid titration, which has shown reliability in work on HAp and related fluoride minerals, with OCP in 100 mM KCl at 37.0 +/- 0.1 degrees C. The constitution of the end point precipitate was determined by X-ray diffraction and selected-electron area diffraction; the particle morphology and elements present were examined by high-resolution field emission scanning, transmission electron microscopy and energy-dispersive X-ray analysis. The titration curve for OCP was found for pH approximately 3.4-7.4. The precipitate was HAp at pH 3.6 and 4.5; no residual OCP or other phase was detected. Dicalcium phosphate dihydrate (DCPD) was then found to form at pH 3.6 on further addition of OCP titrant after equilibrium had been achieved, possibly due to easier nucleation at lower pH. However, markedly crystalline HAp was formed in equilibrium for OCP titration with HAp seeding, verifying HAp as the more stable phase. A solubility isotherm for OCP was not obtained as HAp appears to be less soluble in the pH range studied. This adds weight to the view that HAp may be the most stable phase of all calcium phosphates, with further doubt being cast on DCPD being the most stable phase below pH 4.2. However, metastable DCPD may form in an Ostwald succession, depending on supersaturation and nucleation conditions.


Assuntos
Substitutos Ósseos/química , Fosfatos de Cálcio/química , Hidroxiapatitas/química , Cristalografia , Transição de Fase , Solubilidade , Titulometria , Difração de Raios X
10.
Biomaterials ; 30(23-24): 3810-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19427032

RESUMO

Strontium-containing hydroxyapatite/polyetheretherketone (Sr-HA/PEEK) composites were developed as alternative materials for load-bearing orthopaedic applications. The amount of strontium-containing hydroxyapatite (Sr-HA) incorporated into polyetheretherketone (PEEK) polymer matrix ranged from 15 to 30 vol% and the composites were successfully fabricated by compression molding technique. This study presents the mechanical properties and in vitro human osteoblast-like cell (MG-63) response of the composite material developed. The bending modulus and strength of Sr-HA/PEEK composites were tailored to mimic human cortical bone. PEEK reinforced with 25 and 30 vol% Sr-HA exhibited bending modulus of 9.6 and 10.6 GPa, respectively; alternatively, the bending strengths of the composites were 93.8 and 89.1 MPa, respectively. Based on the qualitative comparison of apatite formation in SBF and quantitative measurement of MG-63-mediated mineralization in vitro, the Sr-HA/PEEK composite was proven to outperform HA/PEEK in providing bioactivity. However, no difference was found in the trend of cell proliferation and alkaline phosphatase activity between different composites. Strontium, in the form of strontium-containing hydroxyapatite (Sr-HA), was confirmed to enhance bioactivity in the PEEK composites.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Durapatita/química , Cetonas/química , Polietilenoglicóis/química , Fosfatase Alcalina/metabolismo , Benzofenonas , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Teste de Materiais , Polímeros , Suporte de Carga
11.
Caries Res ; 43(4): 254-60, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19439946

RESUMO

Solid-titration results for hydroxyapatite (HAp), octacalcium phosphate, beta-tricalcium phosphate and tetracalcium phosphate have shown that the only stable phase in 100 mmol x l(-1) KCl at 37 degrees C is HAp. In particular, dicalcium phosphate dihydrate (DCPD) did not form at pH <4.2 (where it is otherwise believed to be stable) except as a metastable phase under conditions of slight supersaturation. The behaviour of DCPD itself under the same conditions requires checking. Solid titration was used to determine the apparent solubility of DCPD in a 100-mmol x l(-1) KCl solution at 37.0 +/- 0.1 degrees C over the pH range 3.2-11.6. The constitution of the precipitate was determined by X-ray diffraction, particle morphology was observed by scanning and transmission electron microscopy, and the precipitate Ca/P ratio was calculated by energy-dispersive X-ray analysis. The titration curve for DCPD was substantially lower than the position reported elsewhere. DCPD was the only identified phase at equilibrium at pH 3.60 and 4.50, but HAp was formed after seeding with 1 mg HAp at DCPD equilibrium at pH 4.47, 3.60 and 3.30. It is concluded that the titration curve observed for DCPD corresponds to the solubility isotherm for the phase, but that this represents a metastable equilibrium. HAp is more stable than DCPD, particularly below pH 4.2. The implications for calcium phosphate studies are profound as the reverse is generally believed to be true. Thus, solubility results and the nature of the carious lesion need reconsideration.


Assuntos
Substitutos Ósseos/química , Fosfatos de Cálcio/química , Hidroxiapatitas/química , Cristalografia , Transição de Fase , Solubilidade , Titulometria , Difração de Raios X
12.
Arch Oral Biol ; 54(7): 671-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19414172

RESUMO

OBJECTIVE: Using solid titration with hydroxyapatite (HAp) and octacalcium phosphate, HAp has been found to be more stable than dicalcium phosphate dihydrate (DCPD) even at lower pH, inconsistent with the widely reported view that DCPD is less soluble than other calcium phosphates below pH 4.2. A check of the behaviour of other calcium phosphates (TTCP; Ca/P: 2.00 and beta-TCP; Ca/P: 1.33) is necessary. METHODS: Solid titration was used to determine the effective solubility of TTCP and beta-TCP in 100 mM KCl solution at 37.0+/-0.1 degrees C for pH approximately 2.9-9.2 and approximately 3-7.4 respectively. The constitution of the precipitate was determined by XRD, particle morphology was observed by SEM and TEM, and the precipitate Ca/P ratio was calculated by EDX. RESULTS: The only identified solid phase at equilibrium was HAp at both pH 3.60 and 4.50; no residual titrant or other phases were detected. A marked change of slope in the curve occurred at pH approximately 3.9 for TTCP. CONCLUSION: HAp was verified to be more stable than other calcium phosphates, especially at lower pH. That DCPD is more stable below pH 4.2 is contradicted.


Assuntos
Fosfatos de Cálcio/química , Cálcio/análise , Precipitação Química , Durapatita/química , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fósforo/análise , Cloreto de Potássio/química , Solubilidade , Espectrometria por Raios X , Temperatura , Titulometria , Difração de Raios X
13.
Acta Biomater ; 5(5): 1678-85, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19135423

RESUMO

Solid titration was used to explore the solubility isotherms of partially (Srx-HAp, x=1, 5, 10, 40, 60 mol.%) and fully substituted strontium hydroxyapatite (Sr-HAp). Solubility increased with increasing strontium content. No phase other than strontium-substituted HAp, corresponding to the original titrant, was detected in the solid present at equilibrium; in particular, dicalcium hydrogen phosphate was not detected at low pH. The increase in solubility with strontium content is interpreted as a destabilization of the crystal structure by the larger strontium ion. Carbonated HAp was formed in simulated body fluid containing carbonate on seeding with Sr10-HAp, but the precipitate was strontium-substituted on seeding with Sr-HAp. Strontium-substituted HAp might be usable as a template for the growth of new bone, since nucleation appears to be facilitated.


Assuntos
Hidroxiapatitas/química , Estrôncio/química , Titulometria/métodos , Líquidos Corporais , Cálcio/química , Precipitação Química , Concentração de Íons de Hidrogênio , Fosfatos/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
14.
Endoscopy ; 39(8): 679-85, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17661241

RESUMO

BACKGROUND AND STUDY AIMS: Both endoscopic obturation and transjugular intrahepatic portosystemic shunts (TIPSs) have proven to be effective in preventing rebleeding from gastric varices. This study compared the efficacy and complications of these modalities. PATIENTS AND METHODS: Cirrhotic patients with acute bleeding from gastric varices were considered for inclusion. After initial control, eligible patients were randomly allocated to two groups: TIPS (n = 35) and obturation using cyanoacrylate (n = 37). In the cyanoacrylate group, treatment was repeated regularly until gastric varices were obliterated. Patients of both groups received regular follow-up. The end points were gastric variceal rebleeding or death. RESULTS: Stent shunt insertion was successful in all TIPS patients, and mean portal pressure gradient decreased from 21.4 +/- 7.5 mm Hg to 7.5 +/- 3.5 mm Hg ( P < 0.001). Variceal obliteration was achieved in 19 patients in the cyanoacrylate group (51 %) compared with seven TIPS patients (20 %) ( P < 0.02). After a median follow up of 33 months, upper gastrointestinal bleeding occurred in 15 TIPS patients (43 %) and 22 cyanoacrylate patients (59 %) ( P = 0.12). Rebleeding from gastric varices was encountered in four TIPS patients (11 %) and 14 cyanoacrylate patients (38 %) ( P = 0.014; odds ratio 3.6, 95 %CI 1.2 - 11.1). Blood transfusion requirements were lower in the TIPS group than in the cyanoacrylate group ( P < 0.01). Survival and frequency of complications were similar in both groups. CONCLUSIONS: TIPS proved more effective than glue injection in preventing rebleeding from gastric varices, with similar survival and frequency of complications.


Assuntos
Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/prevenção & controle , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Escleroterapia/métodos , Adulto , Fatores Etários , Idoso , Cianoacrilatos/uso terapêutico , Varizes Esofágicas e Gástricas/diagnóstico , Feminino , Seguimentos , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Estudos Prospectivos , Medição de Risco , Prevenção Secundária , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Fatores Sexuais , Análise de Sobrevida , Resultado do Tratamento
15.
Acta Radiol ; 48(4): 401-4, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17453520

RESUMO

We report a 21-year-old woman with a penetrating abdominal wound. Injuries of the abdominal aorta and alimentary tract were found during emergency surgery. The patient had a follow-up computed tomography (CT) scan 3 months after surgery. Arterial-phase 16-row multidetector computed tomography (MDCT) showed a suspicious dilated vessel adjacent to the repaired aorta on 5-mm transverse images. A fistula between a lumbar artery and the inferior vena cava was clearly demonstrated on images reformatted with two- (2D) and three-dimensional (3D) techniques. The patient suffered from symptoms of high-output heart failure 8 months after surgery.


Assuntos
Fístula Arteriovenosa/etiologia , Processamento de Imagem Assistida por Computador/métodos , Vértebras Lombares/irrigação sanguínea , Tomografia Computadorizada por Raios X/métodos , Veia Cava Inferior/patologia , Ferimentos Perfurantes/complicações , Adulto , Aorta Abdominal/lesões , Artérias/patologia , Fístula Arteriovenosa/diagnóstico por imagem , Meios de Contraste , Feminino , Seguimentos , Humanos , Imageamento Tridimensional/métodos , Iopamidol , Mesentério/lesões , Intensificação de Imagem Radiográfica/métodos , Estômago/lesões , Veia Cava Inferior/diagnóstico por imagem
16.
Arch Oral Biol ; 52(9): 861-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17451638

RESUMO

OBJECTIVES: The solubility isotherms, S, of two compounds detected after topical fluoride treatment - calcium fluoride (CaF(2)) and fluorapatite (FAp) - are of fundamental interest in saliva chemistry and in the context of reduction of acid dissolution of teeth, whether through the process of caries or from exogenously ingested acids. Solid titration has shown its reliability and reproducibility for complicated systems that are not suitable for study by the traditional excess-solid method. The primary aim of this work was to ascertain S[CaF(2)] and S[FAp]. METHODS: Solid titration was used for CaF(2) (pH 2.3-9.5) and FAp (pH 2.8-5.1) in 100mM KCl solution at 37.0+/-0.1 degrees C, and further to determine the apparent solubility of hydroxyapatite (HAp) in the presence of 1mM fluoride (pH 3.2-4.8). RESULTS: Peculiar results were obtained at first which were attributed to the adsorption or reaction of fluoride with the reaction vessel glass surface interfering with the intended solution equilibria. Wax-lined glass apparatus resolved this problem. The solubility isotherm of CaF(2) was then as theoretically expected at pH<8, but above this point a new solid species (CaFOH) was postulated to account for the data. The position of FAp was as expected relative to HAp, being about 0.63x less soluble. FAp was the only detectable equilibrium solid at pH 3.2, 3.6 and 4.1. The apparent solubility of HAp was depressed somewhat by the presence of 1mM fluoride. CONCLUSION: The solid titration method was again found to be reliable once glass interferences were eliminated. The interaction of fluoride with borosilicate glass may have affected other work in the field; such work may therefore require re-evaluation. The S[FAp] is very similar to that of HAp determined by solid titration. Excess-solid method results are strongly discrepant from the present determination and may not be reliable, primarily due to lack of solution speciation data for that calculation.


Assuntos
Apatitas/química , Fluoreto de Cálcio/química , Adsorção , Artefatos , Cariostáticos/química , Durapatita/química , Microanálise por Sonda Eletrônica , Fluoretos/química , Vidro/química , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia Eletrônica de Transmissão , Modelos Químicos , Compostos de Potássio/química , Reprodutibilidade dos Testes , Solubilidade , Temperatura , Titulometria , Difração de Raios X
17.
Arch Oral Biol ; 52(7): 618-24, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17240349

RESUMO

OBJECTIVES: The solubility isotherm (S) of hydroxyapatite (HAp) is of fundamental importance to saliva chemistry, dental caries and related contexts. It has previously been shown that the locus of the S[HAp] is substantially lower than is commonly reported, and of different slope, probably due to HAps incongruent dissolution. The aim of the present study was to determine the S[HAp] over a wider pH range and to identify the precipitate formed at equilibrium in HAp solid titration. METHODS: The solid titration technique of Leung and Darvell (Leung VW-H, Darvell BW. Calcium-phosphate system in saliva-like media. J Chem Soc Faraday Trans 1991;87(11):1759-64.) was used to investigate the solubility behaviour of HAp at 37.0+/-0.1 degrees C in 100 mM aqueous KCl. The pH range studied overlapped that of earlier work from pH 3.6 to 5.2, for a reproducibility check and validation, and extended to pH approximately 2.9. XRD and EDX were used to identify the precipitates. SEM and TEM were used to observe the morphology. RESULTS: The previous S[HAp] reported by Chen et al. (Chen Z-F, Darvell BW, Leung VW-H. Hydroxyapatite solubility in simple inorganic solutions. Arch Oral Biol 2004;49(5):359-67.) was reconfirmed. An abrupt change of slope of S[HAp] was detected at pH approximately 3.9. No other phase than HAp was found at pH 3.2, 3.6 and 4.1. In particular, brushite (dicalcium phosphate dihydrate) was not detected, even below pH 3.9, where instead calcium-deficient HAp was formed. CONCLUSION: The solid titration method was reconfirmed as reproducible and to yield HAp from pH 2.9 to 5.2. The expected brushite did not appear, but rather a stable calcium-deficient HAp was consistently formed. The chemistry of calcium phosphates needs to be reevaluated.


Assuntos
Durapatita/química , Ácidos , Cálcio/química , Fosfatos de Cálcio/química , Precipitação Química , Cristalografia , Microanálise por Sonda Eletrônica , Humanos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Transição de Fase , Fósforo/química , Cloreto de Potássio/química , Reprodutibilidade dos Testes , Solubilidade , Temperatura , Titulometria , Difração de Raios X
18.
AJNR Am J Neuroradiol ; 27(4): 813-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16611770

RESUMO

Multidetector CT (MDCT) angiography is an imaging technique that can provide high-resolution and high-contrast images; however, published reports of MDCT angiography in the evaluation of spinal vascular malformations are limited. We present 2 cases in which MDCT angiography led to diagnosis of a type I (spinal dural arteriovenous fistula) in one and type IVA (perimedullary spinal cord simple arteriovenous fistula fed by a single arterial feeder) spinal vascular malformation, both confirmed by conventional angiography. MDCT angiography can localize the feeding vessel and the fistula, thus greatly reducing the amount of time required for conventional angiography.


Assuntos
Angiografia/métodos , Malformações Vasculares do Sistema Nervoso Central/classificação , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Medula Espinal/irrigação sanguínea , Medula Espinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Vértebras Torácicas
19.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 1385-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282456

RESUMO

Recently, the use of MRI contrast agents has been proven to be substantially improved sensitivity and specificity in many clinical applications. CE-MRA has higher blood signal based on the T1 and T2-shortening property of contrast agents, so that even the small vessels can be visualized. The use of contrast agents can improve lesion detection and characterization. The routinely used dose of contrast agents in the routine MRI examinations only relies on the weight of the subject. The purpose of this study is to obtain the clinically optimal dose for 3D-TOF (time-of-flight) pulse sequences for CE-MRA examinations. In the phantom study, ten test tubes were filled with saline mixed with different dose of Gd-DTPA. It is found that the optimal dose of Gd-DTPA for saline phantom by using 3D-TOF pulse sequences is 20 mM. Also, there has no differences of optimal doses between Omniscan and Magnivist contrast agents Gd-DTPA. The results show that consistent high quality CE-MRA images might be obtained by using 0.25M Gd-DTPA (half of the routine dose) with 3~4 cc/sec injection rate for all clinical cases. The benefits of this study might be to minimize dose and potential toxicity. Additionally, the decrease of the cost of contrast agents might be achieved. It is expected to provide the recommended dose of Gd-DTPA for contrast enhanced MRA in clinical routine diagnosis.

20.
Neuroradiology ; 46(3): 216-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14991257

RESUMO

We report a case brachial plexus neuromuscular hamartoma (choristoma) in a 28-year-old man who complained of numbness of the left hand and forearm for several years. MRI revealed a circumscribed, rounded mass in the left brachial plexus. The patient is well 2 years after surgery, with no neurological deficit.


Assuntos
Plexo Braquial , Hamartoma/diagnóstico , Imageamento por Ressonância Magnética , Doenças Neuromusculares/diagnóstico , Adulto , Plexo Braquial/patologia , Plexo Braquial/cirurgia , Hamartoma/cirurgia , Humanos , Masculino , Doenças Neuromusculares/cirurgia
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