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1.
J Dairy Sci ; 97(9): 5383-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25022686

RESUMO

Subcritical water extract (SWE) of Brassica juncea was studied for antiviral effects against influenza virus A/H1N1 and for the possibility of application as a nonfat milk supplement for use as an "antiviral food." At maximum nontoxic concentrations, SWE had higher antiviral activity against influenza virus A/H1N1 than n-hexane, ethanol, or hot water (80°C) extracts. Addition of 0.5mg/mL of B. juncea SWE to culture medium led to 50.35% cell viability (% antiviral activity) for Madin-Darby canine kidney cells infected with influenza virus A/H1N1. Nonfat milk supplemented with 0.28mg/mL of B. juncea SWE showed 39.62% antiviral activity against influenza virus A/H1N1. Thus, the use of B. juncea SWE as a food supplement might aid in protection from influenza viral infection.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Leite/química , Mostardeira/química , Extratos Vegetais/farmacologia , Animais , Cães , Aditivos Alimentares/farmacologia , Hexanos , Células Madin Darby de Rim Canino/efeitos dos fármacos , Água
2.
J Food Sci ; 73(7): C551-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18803701

RESUMO

Effects of riboflavin photosensitization on the distribution of isoflavones in commercially available soymilk were analyzed using high-performance liquid chromatography (HPLC). Total isoflavones (TI) in soymilk with riboflavin (1000 ppm, w/v) under light were significantly different from those stored in the dark for 24 h (P < 0.05), while TI in samples with 0 and 1000 ppm added riboflavin were not significant from each other in dark conditions (P > 0.05). To test the effects of the concentration of riboflavin on TI, soymilk was mixed with riboflavin to make 0, 100, 250, and 500 ppm (w/v) and stored under light at 25 degrees C for 24 h. TI in soymilk with 100 ppm riboflavin under light significantly decreased by 13.5% for 24 h (P < 0.05) compared to control samples and were not significantly different from those with 250 or 500 ppm samples (P > 0.05). Daidzin and genistin were predominant isoflavones in soymilk, and the rate of photo degradation of genistin was higher than that of daidzin for 24 h in soymilk under riboflavin photosensitization.


Assuntos
Isoflavonas/análise , Riboflavina/metabolismo , Leite de Soja/química , Cromatografia Líquida de Alta Pressão , Manipulação de Alimentos , Luz
3.
J Food Sci ; 73(3): C173-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18387095

RESUMO

This study was conducted to determine the optimal temperature and time for the regiospecific oxidation of primary alcohol groups in corn starch with 2,2,6,6-tetramethyl-1-piperidinyl oxoammonium ion (TEMPO) and sodium hyphochlorite (NaOCl). The study also elucidated the molecular structure of fully oxidized corn starch (FOCS) prepared at optimum temperature and physicochemical properties of the partially (10%, 20%, and 30%) oxidized corn starches (POCS). The reaction time rapidly decreased up to 30 degrees C, and then gradually decreased. Selectivity, yield, and viscosity were drastically reduced at temperatures higher than 35 to 40 degrees C. Optimal oxidation temperature for the production of FOCS was determined as 35 degrees C. Regiospecific oxidation of the primary alcohol group without oxidation of the secondary alcohol group was confirmed in (13)C-NMR and IR spectra. Water-binding capacity, swelling power, solubility power, and transmittance of POCS increased as the degree of oxidation increased. Hardness, gumminess, and chewiness of corn starch gel containing POCS were not significantly different from those of native corn starch gel at 1-d storage, but the values of the starch gel containing POCS were smaller than those of the native starch gel after 1-d storage. However, springiness and cohesiveness did not differ significantly among the samples regardless of storage time.


Assuntos
Antioxidantes/química , Óxidos N-Cíclicos/química , Conservação de Alimentos/métodos , Hipoclorito de Sódio/química , Amido/química , Isótopos de Carbono , Tecnologia de Alimentos/métodos , Géis , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxirredução , Solubilidade , Relação Estrutura-Atividade , Temperatura , Fatores de Tempo , Viscosidade , Zea mays/química
4.
J Food Sci ; 72(5): C235-42, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17995708

RESUMO

This study examined the characteristics of the oxidation reaction on the primary alcohol groups in cellulose involving the 2,2,6,6-tetramethyl-1-piperidinyl oxoammonium ion (TEMPO) and determined the optimum conditions for the preparation of oxidized cellulose (OC). The applicability of OC in polysaccharide systems was also investigated. The effects of TEMPO, sodium bromide (NaBr), and temperature on the oxidation reaction time, yield, and selectivity for primary alcohol groups were examined using response surface methodology (RSM). The reaction time decreased with increases in the temperature and the levels of TEMPO and NaBr. The yield increased with the level of NaBr and decreased as the temperature increased. Selectivity increased with the temperature and decreased as the levels of TEMPO and NaBr increased. The optimum levels of TEMPO and NaBr and the optimum temperature for the production of OC were determined as 0.3 mM/100 mM anhydroglucose unit (AGU), 50 mM/100 mM AGU, and 25 degrees C, respectively. The water and oil binding capacity and viscosity of cellulose increased with oxidation. Wheat starch containing OC exhibited a decreased initial pasting temperature and setback, but increased peak viscosity, gelatinization, and retrogradation enthalpy (DeltaH). The hardness of the wheat starch gel decreased significantly upon the addition of OC.


Assuntos
Antioxidantes/química , Celulose/química , Óxidos N-Cíclicos/química , Tecnologia de Alimentos/métodos , Brometos/química , Relação Dose-Resposta a Droga , Estrutura Molecular , Oxirredução , Compostos de Sódio/química , Amido/química , Relação Estrutura-Atividade , Temperatura , Fatores de Tempo , Viscosidade
5.
Infect Immun ; 69(10): 6091-101, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11553547

RESUMO

To examine the hypothesis that the ancestral role of the toxR gene in the family Vibrionaceae is control of the expression of outer membrane protein (OMP)-encoding genes for adaptation to environmental change, we investigated the role of the toxR gene in Vibrio anguillarum, an important fish pathogen. The toxR gene of V. angullarum (Va-toxR) was cloned from strain PT-87050 isolated from diseased ayu (Plecoglossus altivelis), and the sequence was analyzed. The toxR sequence was 63 to 51% identical to those reported for other species of the family Vibrionaceae. Distribution of the Va-toxR gene sequence in V. anguillarum strains of various serotypes was confirmed by using DNA probe and PCR methods. An isogenic toxR mutant of V. anguillarum PT-24, isolated from diseased ayu, was constructed by using an allelic exchange method. The wild-type strain and the toxR mutant did not differ in the ability to produce a protease(s) and a hemolysin(s) or in pathogenicity for ayu when examined by the intramuscular injection and immersion methods. A 35-kDa major OMP was not produced by the toxR mutant. However, a 46-kDa OMP was hardly detected in the wild-type strain but was produced as the major OMP by the toxR mutant. For the toxR mutant, the MICs of two beta-lactam antibiotics were higher and the minimum bactericidal concentration of sodium dodecyl sulfate was lower than for the wild-type strain. Analysis of the N-terminal amino acid sequences of the 35- and 46-kDa OMPs indicated that these proteins are the porin-like OMPs and are related to the toxR-regulated major OMPs of the family Vibrionaceae. The results indicate that the toxR gene is not involved in virulence expression in V. anguillarum PT-24 and that toxR regulation of major OMPs is universal in the family Vibrionaceae. These results support the hypothesis that the ancestral role of the toxR gene is regulation of OMP gene expression and that only in some Vibrio species has ToxR been appropriated for the regulation of a virulence gene(s).


Assuntos
Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Genes Bacterianos/fisiologia , Fatores de Transcrição/genética , Vibrio/genética , Sequência de Aminoácidos , Antibacterianos/farmacologia , Proteínas de Bactérias/fisiologia , Sequência de Bases , DNA Bacteriano , Proteínas de Ligação a DNA/fisiologia , Detergentes/farmacologia , Resistência a Medicamentos , Hemaglutinação , Hemólise , Lactamas , Dados de Sequência Molecular , Mutagênese , Homologia de Sequência de Aminoácidos , Dodecilsulfato de Sódio/farmacologia , Fatores de Transcrição/fisiologia , Vibrio/efeitos dos fármacos , Vibrio/metabolismo , Vibrio/patogenicidade , Virulência
6.
Cell ; 105(7): 851-62, 2001 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-11439182

RESUMO

Serum response factor (SRF) regulates transcription of numerous muscle and growth factor-inducible genes. Because SRF is not muscle specific, it has been postulated to activate muscle genes by recruiting myogenic accessory factors. Using a bioinformatics-based screen for unknown cardiac-specific genes, we identified a novel and highly potent transcription factor, named myocardin, that is expressed in cardiac and smooth muscle cells. Myocardin belongs to the SAP domain family of nuclear proteins and activates cardiac muscle promoters by associating with SRF. Expression of a dominant negative mutant of myocardin in Xenopus embryos interferes with myocardial cell differentiation. Myocardin is the founding member of a class of muscle transcription factors and provides a mechanism whereby SRF can convey myogenic activity to cardiac muscle genes.


Assuntos
Biologia Computacional , Proteínas de Ligação a DNA/metabolismo , Miocárdio/metabolismo , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Ativação Transcricional/genética , Sequência de Aminoácidos , Animais , Células COS , Proteínas de Ligação a DNA/genética , Embrião de Mamíferos/fisiologia , Embrião não Mamífero , Etiquetas de Sequências Expressas , Genes Reporter/genética , Camundongos , Microinjeções , Dados de Sequência Molecular , Músculo Liso/fisiologia , Proteínas Nucleares/química , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Fator de Resposta Sérica , Transativadores/química , Transativadores/genética , Xenopus laevis/embriologia , Xenopus laevis/genética
7.
Pediatr Res ; 50(1): 50-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11420418

RESUMO

MDR3 P-glycoprotein mediates canalicular phospholipid transport in hepatocytes. Defects in the MDR3 gene have been found to cause a subtype of progressive familial intrahepatic cholestasis (PFIC) with high gamma-glutamyltranspeptidase (GGT) levels. Affected children develop proliferation of biliary epithelium, portal inflammation, and biliary cirrhosis. The frequency of MDR3 mutations in patients with high GGT-PFIC is unclear. There have been no Asian patients reported to carry MDR3 mutations. To determine the role of MDR3 defects in chronic cholestatic patients, we studied six Taiwanese children from five families who presented high GGT-PFIC among 47 patients with infantile onset chronic intrahepatic cholestasis. Sequence analysis of MDR3 cDNA from liver tissues was performed. Only one patient had mutation in the MDR3 gene. This patient had a homozygous 719-bp deletion (nucleotide 287 to 1005) of liver cDNA encompassing exon 5 to 9 and leading to protein truncation. The onset age was 1 y in contrast with the other five patients who presented neonatal cholestasis. Four patients without mutation, including one sibling pair, exhibited histologic features of prominent portal fibrosis leading to advanced biliary cirrhosis that were indistinguishable from the case of MDR3 mutation. We concluded that mutations in MDR3 accounted for approximately 2% (1/47) of infantile onset chronic cholestasis in Taiwan. Those patients presenting high GGT-PFIC with early onset cholestasis but without MDR3 mutation probably had inheritable disorders remaining to be clarified.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Colestase Intra-Hepática/enzimologia , Colestase Intra-Hepática/genética , Mutação , gama-Glutamiltransferase/metabolismo , Adolescente , Sequência de Bases , Criança , Colestase Intra-Hepática/etnologia , Colestase Intra-Hepática/patologia , Primers do DNA , Feminino , Humanos , Lactente , Taiwan
8.
J Biol Chem ; 276(20): 17206-12, 2001 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-11278806

RESUMO

Serum response factor (SRF) is a MADS box transcription factor that regulates muscle-specific and growth factor-inducible genes by binding the consensus sequence CC(A/T)6GG, known as a CArG box. Because SRF expression is not restricted solely to muscle, its expression alone cannot account for the muscle specificity of some of its target genes. To understand further the role of SRF in muscle-specific transcription, we created transgenic mice harboring lacZ transgenes linked to tandem copies of different CArG boxes with flanking sequences. CArG boxes from the SM22 and skeletal alpha-actin promoters directed highly restricted expression in developing smooth, cardiac, and skeletal muscle cells during early embryogenesis. In contrast, the CArG box and flanking sequences from the c-fos promoter directed expression throughout the embryo, with no preference for muscle cells. Systematic swapping of the core and flanking sequences of the SM22 and c-fos CArG boxes revealed that cell type specificity was dictated in large part by sequences immediately flanking the CArG box core. Sequences that directed widespread embryonic expression bound SRF more strongly than those that directed muscle-restricted expression. We conclude that sequence variations among CArG boxes influence cell type specificity of expression and account, at least in part, for the ability of SRF to distinguish between growth factor-inducible and muscle-specific genes in vivo.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas Musculares/genética , Músculo Esquelético/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Actinas/genética , Animais , Sequência de Bases , Embrião de Mamíferos , Genes fos , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Especificidade de Órgãos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Fator de Resposta Sérica , Fatores de Transcrição/metabolismo , beta-Galactosidase/genética
9.
Carbohydr Res ; 329(4): 913-22, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11125837

RESUMO

Eleven different glucans (wheat starch, potato amylopectin, potato amylose, pullulan, alternan, regular comb dextran, alpha-cellulose, microcrystalline cellulose, CM-cellulose, chitin, and chitosan) that had their C-6 primary alcohol groups oxidized to carboxyl groups by reaction with 2,2,6,6-tetramethyl-1-piperidine oxoammonium ion (TEMPO), were reacted with Azotobacter vinelandii poly-beta-(1-->4)-D-mannuronic acid C-5-epimerase. All of the oxidized polysaccharides reacted with the C-5-epimerase, as evidenced by comparing: (1) differences in the relative viscosities; (2) differences in the carbazole reaction; (3) differences in their susceptibility to acid hydrolysis, and (4) differences in their ability to form calcium gels, before and after reaction. We further show the formation of L-iduronic acid from D-glucuronic acid for oxidized and epimerized amylose by 2D NOESY and COSY + 1H NMR.


Assuntos
Alginatos/química , Azotobacter vinelandii/enzimologia , Carboidratos Epimerases/metabolismo , Glucanos/química , Glucanos/metabolismo , Configuração de Carboidratos , Carboidratos Epimerases/isolamento & purificação , Óxidos N-Cíclicos/química , Géis , Hidrólise , Espectroscopia de Ressonância Magnética , Oxirredução , Marcadores de Spin , Viscosidade
11.
Acta Paediatr Taiwan ; 40(1): 50-2, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10910588

RESUMO

Eikenella corrodens is a rare cause of hepatic abscess. We report a case of a hepatic abscess caused by (1) Bacteroides fragilis, (2) Streptococcus constellatus and (3) E. corrodens, which illustrates potential problems of antibiotic coverage due to the presence of Eikenella species. The infection followed an episode of acute gastroenteritis and the clinical course appeared indolent evolving over one week. Besides empirical antibiotics, initial percutaneous aspiration was performed and yielded pus which grew E. corrodens concomitantly with Streptococcus species. E. corrodens was sensitive to penicillin but resistant to clindamycin and metronidazole. But B. fragilis was resistant to penicillin. So the antibiotics were switched to amoxicillin/clavulanate. Unfortunately fever persisted and the abscess increased in size. Therefore echo-guided percutaneous drainage with pigtail catheter was installed. Fever subsided 5 days later. After 21 days treatment of antibiotics, the patient was discharged in good condition despite having some sterile fluid in the residual abscess cavity. Two months after discharge the follow-up echogram confirmed complete resolution of the residual abscess. This patient shows us the existence of E. corrodens in pediatric patients, especially when the hepatic abscess is very likely from the spread of an oral or abdominal infection.


Assuntos
Eikenella corrodens/isolamento & purificação , Abscesso Hepático/microbiologia , Antibacterianos/uso terapêutico , Pré-Escolar , Eikenella corrodens/efeitos dos fármacos , Humanos , Abscesso Hepático/terapia , Masculino
12.
Anal Biochem ; 258(1): 59-62, 1998 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-9527848

RESUMO

A relatively simple assay procedure for measuring the reactions catalyzed by polyuronic acid C-5 epimerases has been developed. Action of C-5 epimerases inverts the C-6 carboxyl group of polyuronic acids converting beta-linked residues into alpha-linked residues or vice versa. The assay takes advantage of the greater susceptibility of the acid hydrolysis of alpha-glycosidic linkages than beta-glycosidic linkages. The method involves the partial acid hydrolysis of the polyuronic acid before and after reaction with the C-5 epimerase. The greater or lesser amounts of uronic acid released (solubilized) before and after reaction of the C-5 epimerase are a measure of the amount of alpha- or beta-glycosidic linkages that are formed and a measure of the amount of catalysis by the enzyme.


Assuntos
Carboidratos Epimerases/análise , Alginatos/química , Azotobacter vinelandii/enzimologia , Configuração de Carboidratos , Carboidratos Epimerases/metabolismo , Glucuronatos/análise , Glucuronatos/metabolismo , Ácido Glucurônico , Ácidos Hexurônicos/análise , Ácidos Hexurônicos/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Espectrofotometria , Ácidos Urônicos/química
13.
J Formos Med Assoc ; 97(12): 873-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9884493

RESUMO

A prematurely born 5-year-old boy with chronic lung disease, hypoxic-ischemic encephalopathy, cerebral palsy, repeated aspiration pneumonia, and stroke underwent percutaneous endoscopic jejunostomy (PEJ) to alleviate repeated aspiration pneumonia. Studies, including 24-hour esophageal pH monitoring, 99mTc gastric emptying time, upper gastroesophageal barium radiography, and endoscopic examinations showed severe gastroesophageal reflux and prolonged gastric emptying. Percutaneous endoscopic gastrostomy (PEG) was performed first, followed by placement of a polyurethane J-tube (9 French) through the preexisting gastrostomy site. We passed the style-guided J-tube through the pyloric ring endoscopically and advanced it to the jejunum. The position of the J-tube was confirmed by radiologic study. Feeding with an elemental formula, 20 mL/hour, commenced immediately after the procedure, and the rate was gradually increased to 50 mL/hour. No further episodes of aspiration pneumonia have occurred since J-tube placement. Our initial experience with jejunal feeding through a PEJ is encouraging.


Assuntos
Gastrostomia , Jejunostomia/métodos , Pré-Escolar , Endoscopia Gastrointestinal , Humanos , Masculino
14.
Kaohsiung J Med Sci ; 13(10): 631-4, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9385780

RESUMO

The main purpose of this study is to find out the degree of attenuation when the x-ray entrances the skin and reaches the film at the bone area near the mandibular premolar root apex. In this study we used thermaluminescent dosimeters (TLDs) to measure the entrance dose and exit dose directly at the area of interest and calculated the penetration value P. We also simulated the attenuation process and calculated the P value in similar conditions. The results indicate that the mean P value of direct measurement from patient is 0.071 +/- 0.018 (60kVp, HVL = 1.5mm Al), while that for theoretical calculation is 0.06458 at 27keV. We concluded that P value of direct measurement can match with the theoretical value and further studies in jaw bone density and other related portions is worthwhile.


Assuntos
Processo Alveolar/efeitos da radiação , Mandíbula/efeitos da radiação , Músculos/efeitos da radiação , Doses de Radiação , Feminino , Humanos , Masculino
15.
Kaohsiung J Med Sci ; 12(9): 522-8, 1996 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-8819355

RESUMO

The linear attenuation coefficient (mu) is an important coefficient in the study of diagnostic radiology. The mu values of dentin and enamel were rarely reported because they are thin and tightly connected to each other and are difficult to measure by thermoluminescent dosimeters or ion chambers. In this work, we used film densitometry to measure the radiation dose before and after they transmitted the 2 mm thickness tooth slice and used this data to calculate the mu values of enamel and dentin. The results show that the mu values of enamel at 70, 80, 90kVp are 2.97 +/- 0.71, 2.85 +/- 0.07, 2.70 +/- 0.16 cm-1, respectively. The mu values of dentin at 70, 80, 90kVp are 2.12 +/- 0.92, 1.81 +/- 0.23, 1.89 +/- 0.42 cm-1, respectively. The mu values may be affected by the equivalent energy of an x-ray generator operated under different kVp conditions and also by the density and calcification degree of the enamel and dentin. Nevertheless, the results obtained in this study still can severe as a reference for researchers.


Assuntos
Radiografia Dentária , Esmalte Dentário , Dentina , Humanos
16.
Am J Sports Med ; 24(5): 688-92, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8883694

RESUMO

Chronic tibial stress fracture is an unusual condition that is primarily seen in athletes and military personnel. Recurrent or recalcitrant stress fractures can be career-ending because they require lengthy nonoperative treatment. We performed a retrospective review of five patients who underwent intramedullary tibial nailing for recalcitrant stress fractures at Womack Army Medical Center, Ft. Bragg, North Carolina, from 1991 to 1994. Interviews were used to survey the patient's history and outcome. We reviewed each case regarding preoperative symptoms, preoperative treatment, surgery performed, radiographic findings, and functional outcome. In each case there were several similarities in symptoms and, most notably, radiographic findings and failure of nonoperative therapy for more than 1 year. Each patient had an unusually narrow medullary canal, a thickened anterior cortex, and a linear unicortical fracture line on the anterior or tension side. Although functional results varied, all patients reported improvement in their symptoms and could return to limited running. There were two excellent results (defined as unlimited pain-free running and resolved tibial pain) and three good results. We believe intramedullary tibial nailing should be considered for treating chronic stress fractures of the midanterior tibia that are recalcitrant to nonoperative therapy in a selected group of patients.


Assuntos
Fixação Intramedular de Fraturas/métodos , Fraturas de Estresse/cirurgia , Fraturas da Tíbia/cirurgia , Adulto , Traumatismos em Atletas/cirurgia , Medula Óssea/diagnóstico por imagem , Pinos Ortopédicos , Moldes Cirúrgicos , Doença Crônica , Seguimentos , Fraturas de Estresse/diagnóstico , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/terapia , Marcha/fisiologia , Humanos , Masculino , Militares , Doenças Profissionais/cirurgia , Manejo da Dor , Radiografia , Estudos Retrospectivos , Corrida/fisiologia , Tíbia/diagnóstico por imagem , Fraturas da Tíbia/diagnóstico , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/terapia , Resultado do Tratamento , Suporte de Carga
17.
Zhonghua Yi Xue Za Zhi (Taipei) ; 55(4): 283-9, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7796354

RESUMO

BACKGROUND: Computed tomography (CT) is one of the most frequently used examination procedures in diagnostic radiology and the dose given to the patients is higher than in general radiographic procedures. In this study LiF chip thermoluminescent dosimeters (TLD-100) were placed in each relative organ or tissue position, including head, chest and abdomen, in a Rando phantom. CT was performed using both conventional and spiral modes, and effective dose and effective dose equivalent were assessed for each organ or tissue scanned. METHODS: The TLD reader used in this experiment was controlled at a nitrogen flow rate of 450 ml/min, preheat time of 14 seconds, reading time of 16 seconds and annealing time of 16 seconds. This CT scanner can be used to perform both conventional and spiral tomography. Operating conditions for spiral tomography were 120 kV, 80 mA for scout film, and 120 kV, 200 mA, 1 sec/slice for each scanning. However, for conventional tomography, the operating conditions were 120 kV, 80 mA for scout film and 120 kV, 160 mA, 1.5 sec/slice for each scanning. These operating conditions are satisfactory to most clinical applications, and therefore were adopted for the present studies. RESULTS: Results showed that, in both effective dose and effective dose and effective dose equivalent, conventional tomography was higher than spiral tomography. The average effective doses for each part were measured to be 1.89 and 4.95 mSv for the head, 30.01 and 40.65 mSv for the chest, and 12.85 and 19.62 mSv for the abdomen of spiral and conventional CT, respectively. Higher carcinogenic risk was assessed in organs such as liver, lung, stomach and bone marrow, other organs had a relatively lower incidence of risk. CONCLUSIONS: The main purpose of this study was to obtain distribution values of effective dose and effective dose equivalent, and to know the probability of carcinogenic effect upon each organ or tissue after CT scanning. Results showed the average effective dose for spiral CT to be less than conventional CT, and the dose in the body surface was generally lower than the dose in the central region.


Assuntos
Tomografia Computadorizada por Raios X/efeitos adversos , Humanos , Doses de Radiação , Risco , Tomografia Computadorizada por Raios X/métodos
18.
Gaoxiong Yi Xue Ke Xue Za Zhi ; 10(10): 565-77, 1994 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-7807613

RESUMO

To measure the absorbed dose and evaluate the radiation risk of patient from full mouth series intraoral dental radiography, we used the LiF thermoluminescent dosimeters (TLD-100 chips) to detect the radiation dose of patients and RT-HUMANOID phantom as well. We also used water phantom and extracted human teeth to simulate the oral cavity and measure the absorbed dose of tooth while the intraoral dental radiography was taken. The average absorbed dose of skin near the thyroid gland of patient is 72.2 mu Gy from full mouth series intraoral radiograph with 14 dental films (speed D) using Gendex Panelipse II X-ray machine (75-80kVp, 15mA, 0.25s, FSD = 34-36 cm) with neck shield protection, and the radiation risk of thyroid gland of stochastic effect is estimated to be 3.6 x 10(-8). We also calculated the effective atomic number of enamel and dentin for obtaining the conversion factor of tooth. Four sets of figures were drawn to express the absorbed dose in water phantom and tooth in some different exposure conditions.


Assuntos
Doses de Radiação , Radiografia Dentária/efeitos adversos , Humanos , Fatores de Risco
19.
Ann Otol Rhinol Laryngol ; 102(10): 814-7, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8215105

RESUMO

Inbred LP/J mice have been observed to spontaneously develop abnormal bony lesions of the ossicles and otic capsule that progress throughout the life of the animals. This genetically inherited murine disorder produces bony lesions that share some gross and histologic features with bony lesions seen in human tympanosclerosis. Previous studies on LP/J mice have demonstrated evidence of immunologically mediated injury in the progression of the newly forming bony lesions. This study was designed to examine the effects of dexamethasone on the development of the bony lesions in LP/J mice. The purpose was to attempt to elucidate the relationship of the immunologic injury observed in earlier studies and the progression of the dysplastic bony lesions. The results show that LP/J mice treated with dexamethasone developed significantly fewer dysplastic bony lesions compared to the age-matched, saline-treated controls. There was also a statistically significant difference in the quantity and cellularity of the middle ear effusions between the experimental and control animals.


Assuntos
Dexametasona/farmacologia , Ossículos da Orelha/patologia , Osso Temporal/patologia , Animais , Depressão Química , Camundongos , Camundongos Endogâmicos , Otite Média com Derrame/patologia , Esclerose
20.
J Invertebr Pathol ; 62(2): 116-20, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8228316

RESUMO

The purpose of this paper was to purify and amplify the DNA fragment of Penaeus monodon-type baculovirus (MBV). Using 30-50% caesium chloride gradients, MBV virions and occlusion bodies with density parameters of 1.28-1.29 and 1.32-1.33 g/ml, respectively, were purified. Two oligonucleotide primers have been successfully designed and utilized for the amplification of a DNA fragment of MBV. After 35 amplification cycles of the MBV DNA fragment, a large amount of amplified product with an approximate molecular weight of 600 bp was obtained. This is the first successfully published work on the amplification of MBV using the polymerase chain reaction (PCR). Using the same primers, DNA extracted from MBV noninfected P. monodon, P. japonicus, and P. orientalis had a negative PCR response. However, a positive PCR response was obtained from DNA extracted from MBV-infected postlarval P. monodon. DIG-dot blot hybridization technique using PCR product obtained from the present study as a probe further confirmed that the product is originated from a portion of MBV polyhedrin gene. It is also suggested that PCR product may be beneficial for an accurate and early diagnosis of MBV infection in larval shrimp.


Assuntos
Baculoviridae/genética , DNA Viral/isolamento & purificação , Penaeidae/microbiologia , Reação em Cadeia da Polimerase , Animais , Baculoviridae/isolamento & purificação , Baculoviridae/ultraestrutura , Sequência de Bases , DNA Viral/genética , Larva , Dados de Sequência Molecular
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