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1.
Int J Vitam Nutr Res ; 74(4): 269-78, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15580809

RESUMO

This randomized, double-blind, placebo-controlled study assessed the safety, tolerability, and plasma-kinetic behavior of 94% pure crystalline epigallocatechin gallate (EGCG) after ten days' repeated dosing in 36 healthy male volunteers. Each of the three treatment groups consisted of 12 subjects; nine of them received oral EGCG in one dose of 200, 400, or 800 mg daily, and three received a placebo. Blood samples for plasma-kinetic EGCG characterization were taken on day 1 and day 10. Kinetic parameters for rate and extent, elimination half-lives, and accumulation factor (R) were determined and compared between day 1 and day 10 for each dosage group. Orally administered EGCG is rapidly absorbed from the gut. Dose linearity was applied for single-dose application (day 1). After repeated dosing (day 10) dose linearity was applied between the 200 mg and 400 mg group. Dose escalation to 800 mg was more than dose-proportional in rate and extent, and statistically different from the 200 mg and 400 mg group. An increase in elimination half-life (t1/2.z) and in the accumulation factor (R) in the 800 mg dosage group indicates dose-dependent saturation of capacity-limited excretion routes or an increase of hepato-duodenal re-circulation. Ten days' repeated administration of oral doses of EGCG of up to 800 mg per day were found to be safe and very well tolerated.


Assuntos
Camellia sinensis/química , Catequina/análogos & derivados , Catequina/administração & dosagem , Catequina/farmacocinética , Folhas de Planta/química , Adolescente , Adulto , Catequina/sangue , Método Duplo-Cego , Meia-Vida , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Placebos
2.
Eur J Clin Nutr ; 58(3): 409-19, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14985678

RESUMO

OBJECTIVE: This study validates different definitions of reported night blindness (XN) in a vitamin A deficient African population with no local term for XN. DESIGN: Case-control study with follow-up after treatment. SETTING: Eight primary schools and health centres in rural Tanzania. SUBJECTS: A total of 1214 participants were screened for reported XN and other eye signs of xerophthalmia: 461 children aged 24-71 months, 562 primary school-age children and 191 pregnant or breast-feeding women. All 152 cases of reported XN were selected for the validation study and group matched with 321 controls who did not complain of XN. XN reports were validated against serum retinol concentrations and pupillary dark adaptation measurements in cases and controls. INTERVENTION: All children and women who reported XN or had other signs of active xerophthalmia were treated with vitamin A and followed up 3-4 weeks later. Half of the untreated control group who had their serum retinol examined in the baseline examination were also followed up. RESULTS: The overall prevalence of reported XN was 12.5%. At baseline, mean pupillary threshold (-1.52 vs -1.55 log cd/m(2), P=0.501) and median serum retinol concentrations (0.95 vs 0.93 micromol/l, P=0.734) were not significantly different in cases and controls either overall or in each population group. More restricted case definitions reduced the prevalence of reported XN to 5.5% (P<0.001), but there was still no significant difference between cases and controls although the results were in the expected direction. After treatment, the median serum retinol concentration improved significantly only in the most deficient group, the young children. Dark adaptation improved in all the subgroups but the difference was only significant for young children and primary school-age children when the restricted case definitions were used. CONCLUSIONS: XN reports are a poor indicator of vitamin A deficiency in this population. SPONSORSHIP: Task Force Sight and Life, Basel, Switzerland.


Assuntos
Cegueira Noturna/epidemiologia , Deficiência de Vitamina A/epidemiologia , Vitamina A/sangue , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Cegueira Noturna/sangue , Gravidez , Prevalência , População Rural , Tanzânia/epidemiologia , Deficiência de Vitamina A/sangue , Xeroftalmia/sangue , Xeroftalmia/epidemiologia
5.
Phytother Res ; 14(8): 638-40, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11114003

RESUMO

The aqueous and ethanol extracts from the leaves of Gochnatia polymorpha and further fractions obtained from the latter extract using solvents with increasing polarity, including its aqueous residue and the amino acid, 4-hydroxy-N-methyl-proline were investigated by carrageenin-induced pedal oedema formation. It was shown that the aqueous and ethanol extracts and the ethyl acetate fraction demonstrated significant antiinflammatory activity. The chemical investigation of the latter fraction revealed the presence of caffeic acid, chlorogenic acid, 3-0-methylquercetin, hyperosid and rutin. The amino acid 4-hydroxy-N-methyl-proline, a nonprotein amino acid that has not been reported before in the Asteraceae was isolated as a major compound and identified by spectroscopic methods.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Flavonóis , Extratos Vegetais/química , Plantas Medicinais/química , Quercetina/análogos & derivados , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Antioxidantes/isolamento & purificação , Antivirais/isolamento & purificação , Brasil , Ácidos Cafeicos/isolamento & purificação , Ácido Clorogênico/isolamento & purificação , Cromatografia em Gel , Cromatografia em Camada Fina , Edema/tratamento farmacológico , Folhas de Planta/química , Prolina/isolamento & purificação , Quercetina/isolamento & purificação , Ratos , Rutina/isolamento & purificação
6.
Anat Rec ; 253(2): 49-57, 1998 04.
Artigo em Inglês | MEDLINE | ID: mdl-9605360

RESUMO

One goal of a medical school education is to teach the anatomy of the living human. With the exception of some surface anatomy, the morphology education that goes on during a surgical procedure, and patient observation, live human anatomy is most often taught by simulation. Medical anatomy courses utilize cadavers to approximate the live human. Case-based curricula simulate a patient and present symptoms, signs, and history to mimic reality for the future practitioner. Radiology has provided images of the morphology, function, and metabolism of living humans but with images foreign to most novice observers. With the Visible Human database, computer simulation of the live human body will provide revolutionary transformations in anatomical education.


Assuntos
Anatomia Transversal/educação , Simulação por Computador , Instrução por Computador , Bases de Dados Factuais , Educação Médica/métodos , Humanos , Modelos Anatômicos , National Library of Medicine (U.S.) , Estados Unidos
7.
Lipids ; 32(11): 1189-200, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9397405

RESUMO

Besides some usual fatty acids (FA), two conjugated ene-yne acetylenic FA [trans-10-heptadecen-8-ynoic acid (pyrulic acid) (7.4%), and trans-11-octadecen-9-ynoic acid (ximenynic acid) (3.5%)], a novel ene-yne-ene acetylenic FA [cis-7, trans-11-octadecadiene-9-ynoic acid (heisteric acid) (22.6%)], and 9,10-epoxystearic acid (0.6%) could be identified in the seed oil of Heisteria silvanii (Olacaceae). Two further conjugated acetylenic FA [9,11-octadecadiynoic acid (0.1%) and 13-octadecene-9,11-diynoic acid (0.4%)] were identified tentatively by their mass spectra. The FA mixture has been analyzed by gas chromatography/mass spectrometry (GC/MS) of their methyl ester and 4,4-dimethyloxazoline derivatives. The structure of heisteric acid was elucidated after isolation via preparative silver ion thin-layer chromatography and by various spectroscopic methods [ultraviolet; infrared; 1H, 13C nuclear magnetic resonance (NMR); 1H-1H and 1H-13C correlation spectroscopy]. To determine the position of the conjugated ene-yne-ene system, the NMR spectra were also measured after addition of the lanthanide shift reagent Resolve-Al EuFOD. Furthermore, the triyglyceride mixture was analyzed by high-temperature GC and high-temperature GC coupled with negative chemical ionization MS. A glass capillary column coated with a methoxy-terminated 50%-diphenyl-50%-dimethylpolysiloxane was used for the separation of the triacylglycerol (TAG) species. No evidence of decomposition of the TAG species containing conjugated ene-yne-ene FA was observed. Twenty-six species of the separated TAG were identified by means of their abundant quasi molecular ion [M - H]- and their corresponding carboxylate anions [RCOO]- of the fatty acids, respectively. The major molecular species of the TAG were found to be 16:0/18:1/18:1, 16:0/18:1/18:3 (heisteric acid), 17:2 (pyrulic acid)/18:1/18:1, 18:1/18:1/18:3 (heisteric acid). The TAG containing acetylenic FA showed an unexpected increase of the retention time in comparison to the TAG containing usual FA, thus making the prediction of the elution order of lipid samples containing acetylenic FA difficult.


Assuntos
Acetileno/análise , Ácidos Graxos/análise , Ácidos Oleicos/análise , Óleos de Plantas/química , Sementes/química , Ácidos Esteáricos/análise , Cromatografia Gasosa , Esterificação , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Ácidos Oleicos/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Ácidos Esteáricos/química
8.
Lipids ; 32(5): 549-57, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9168462

RESUMO

The seed oil of Sebastiana commersoniana (Euphorbiaceae) was separated into triglyceride and an estolide fraction by preparative thin-layer chromatography. The triglyceride band was characterized by spectroscopic methods, and its fatty acids have been analyzed by gas chromatography (GC) and GC-mass spectrometry (MS) as their methyl esters. Linolenic acid was the main fatty acid (65%). The estolide band was examined by a combination of spectroscopic and chromatographic methods (ultraviolet, infrared, nuclear magnetic resonance, fast atom bombardment-MS, GC-MS of the fatty acids before and after silylation) and was identified as a tetraglyceride, where one alpha-carbon of the triglyceride backbone was esterfied with 8-hydroxy-5,6-octadienoic acid, which itself was esterfied with trans-2,cis-4-decadienoic acid. The remaining positions of the triglyceride backbone were occupied by common fatty acids.


Assuntos
Alcadienos/química , Ácidos Graxos Insaturados/química , Óleos de Plantas/química , Sementes/química , Triglicerídeos/química , Cromatografia em Camada Fina , Ésteres/química , Ácidos Graxos/análise , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , América do Sul , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Trimetilsilil/química , Ácido alfa-Linolênico/análise
10.
Stud Health Technol Inform ; 39: 155-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-10168913

RESUMO

The University of Colorado's Center for Human Simulation has developed fundamental algorithms for real-time visual and haptic interaction with polygonal and voxel base data sets, including those derived from the Visible Human Dataset. These algorithms are currently being used to create prototype simulators for surgery, needle insertion (anesthesiology, radiology, and rheumatology), dentistry, and ophthalmology. This paper briefly discusses our segmentation and classification effort as well as our ability to create texture-mapped polygonal models directly from the data: both are fundamental to the creation of anatomically based simulators.


Assuntos
Anatomia , Simulação por Computador , Tomada de Decisões Assistida por Computador , Interface Usuário-Computador , Algoritmos , Feminino , Humanos , Masculino
12.
Clin Orthop Relat Res ; (331): 23-8, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8895615

RESUMO

Traditional images of the distal femur place the intercondylar groove midway between the condyles. The location of the sulcus of the intercondylar groove in a large Sudanese skeletal population was verified using a custom stereotactic device. The results of this study show that the femoral sulcus is lateral to the midplane between the 2 femoral condyles. This study also shows that the configuration of the sulcus is linear and is oriented between the traditional anatomic and mechanical axes of the femur.


Assuntos
Antropometria/métodos , Fêmur/anatomia & histologia , Adulto , Antropologia Física , Distinções e Prêmios , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ortopedia , Estados Unidos
14.
J Am Med Inform Assoc ; 3(2): 118-30, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8653448

RESUMO

The National Library of Medicine's Visible Human Male data set consists of digital magnetic resonance (MR), computed tomography (CT), and anatomic images derived from a single male cadaver. The data set is 15 gigabytes in size and is available from the National Library of Medicine under a no-cost license agreement. The history of the Visible Human Male cadaver and the methods and technology to produce the data set are described.


Assuntos
Modelos Anatômicos , Adulto , Cadáver , Fluoroscopia , Congelamento , Técnicas Histológicas , Humanos , Imageamento por Ressonância Magnética , Masculino , Inclusão do Tecido , Tomografia Computadorizada por Raios X
15.
Stud Health Technol Inform ; 29: 542-5, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-10163781

RESUMO

The Visible Human Database provides a complete submillimeter photographic and radiological description of both a male and a female cadaver. The Center for Human Simulation has developed real-time algorithms that allow a user to wield a virtual scalpel and produce arbitrary cuts into the reconstructed body. Real-time interaction is achieved by producing the appropriate texture mapped surfaces directly from the Visible Human Database. We are currently combining a 3 degree of freedom PHANToM haptic device (SensAble Devices) with our surgical cutting algorithms to produce a system with the look and feel of surgical cutting.


Assuntos
Anatomia Transversal , Simulação por Computador , Cirurgia Geral , Tato , Interface Usuário-Computador , Feminino , Humanos , Sistemas de Informação , Masculino
16.
Medinfo ; 8 Pt 2: 1195-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8591405

RESUMO

The National Library of Medicine (NLM) has long been a world leader in the archiving and distribution of the print-based images of biology and medicine. NLM has also been a pioneer in the use of computer systems to encode and distribute textual knowledge of the life sciences. NLM's Long Range Planning effort of 1985-86 foresaw a coming era where NLM's bibliographic and factual database services would be complemented by libraries of digital images, distributed over high speed computer networks and by high capacity physical media. The NLM Planning Panel on Electronic Imaging recommended that NLM should undertake the building of a digital image library consisting of computer-assisted tomography (CAT), magnetic resonance interferometry (MRI), and cryosection images of a representative, carefully selected and prepared male and female cadaver--the "Visible Human Project." The male Visible Human data set is now being made available through a license agreement with the NLM. A wide range of educational, diagnostic, treatment planning, and commercial uses is predicted. The Visible Human data set and its associated identification maps will serve as a "Boston Teapot" for medical imaging, a common public domain data set against which all medical imaging algorithms can be tested, and a cornerstone for future sets of related image libraries.


Assuntos
Modelos Anatômicos , Tomografia Computadorizada por Raios X , Adulto , Algoritmos , Anatomia/educação , Instrução por Computador , Apresentação de Dados , Tomada de Decisões Assistida por Computador , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Serviços de Informação , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , National Library of Medicine (U.S.) , Sistemas de Informação em Radiologia , Estados Unidos
19.
J Digit Imaging ; 4(1): 28-38, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2029570

RESUMO

Some nuclear medicine computer displays, as well as many image processing workstations are "true color" machines characterized by independent memory and grey scale mapping for each of the red, green and blue color channels. Other color image display systems produce a color image from a single grey scale map composed of red, green, and blue intensity values ("pseudo color"). In the true color system the final image is obtained by overlays of three independent color images. In an effort to present complete nuclear medicine studies for diagnosis from cathode-ray tubes (CRTs) we have employed a true color display to present three times as much spatial information as the system was designed for by directing each color output from the display controller to a different monochrome black and white (b/w) monitor. Therefore our system displays a 512 x 512 x 24-bit true-color image, or three 512 x 512 x 8-bit monochrome images, or any combination of smaller size matrices. Monitor requirements, cabling, and general software considerations are detailed here. The ability to display complete nuclear medicine studies on CRTs (as currently presented on film) has been provided by adding monitors and software revisions to a commercially available nuclear medicine computer system.


Assuntos
Apresentação de Dados , Sistemas de Informação em Radiologia , Cor
20.
Invest Radiol ; 22(4): 311-4, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3583650

RESUMO

Sixteen observers averaging 7.4 years experience in interpreting radiology images and 16 observers without radiology training were tested for their ability to detect low-contrast signals in structured noise backgrounds using a digital display system. No significant difference in true positives, false positives, time to complete test, or a calculated "performance value" could be detected between the two groups. Data from the beginning and end of the test indicated that no difference in performance between groups evolved as the test progressed. Therefore, radiology training seems to offer no significant advantage in low-contrast signal detection in an unfamiliar structured noise background, nor in rapid development of better search strategies or decision criteria.


Assuntos
Educação Médica , Radiologia/educação , Percepção Visual , Adulto , Erros de Diagnóstico , Humanos , Psicofísica , Radiografia
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