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1.
Phytopathology ; 105(10): 1373-88, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25938177

RESUMO

Young vine decline (YVD) is a complex disease caused by at least 51 different fungi and responsible for important economic losses to the grapevine industry worldwide. YVD fungi are known to occur in planting material. Hence, detection prior to planting is critical to assure longevity of newly established vineyards. A DNA macroarray based on reverse dot-blot hybridization containing 102 oligonucleotides complementary to portions of the ß-tubulin region was developed for detection of YVD fungi. Specificity of the array was first evaluated against 138 pure fungal cultures representing 72 different taxa from nine genera, including 37 YVD species. In total, 61 species, including 34 YVD pathogens, were detected and identified by the array. The detection limit of the array was below 0.1 pg of genomic DNA. The array was validated against artificially inoculated canes and soil and commercial planting material, with the latter showing a high incidence of YVD fungi in nursery plants otherwise not detected by traditional plating and culturing. This DNA array proved to be a rapid and specific tool to simultaneously detect and identify most YVD fungi in a single test, which has the potential to be used in commercial diagnostics or by the grapevine nursery industry to determine the health status of the planting material.


Assuntos
Fungos/isolamento & purificação , Doenças das Plantas/microbiologia , Vitis/microbiologia , Fungos/genética , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Tubulina (Proteína)/genética
2.
Plant Dis ; 98(4): 456-468, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30708694

RESUMO

Black foot disease of grapevines, caused by several fungal species in the genera Campylocarpon, Cylindrocarpon, Cylindrocladiella, and Ilyonectria, causes significant economic losses to the grapevine industry worldwide. This study represents the first attempt to identify and characterize the fungal pathogens associated with black foot disease of grapevines in British Columbia (BC). Field surveys conducted throughout all grape-growing regions in BC that included assessment of foliar symptomatology and isolations from symptomatic vines showed Cylindrocarpon/Ilyonectria spp. occurred in 32 of 90 (35.5%) young vineyards surveyed (≤8 year old) and in 41 of 215 (19%) samples collected. In 20 of the 41 (48.8%) samples, Cylindrocarpon/Ilyonectria spp. were the sole fungi isolated from symptomatic tissue. In the rest of the samples, black foot fungi were found to primarily coexist with fungal taxa associated with Petri disease of grapevines. Colony and conidia phenotypical characterization, along with DNA analyses of the internal transcribed spacer region (ITS1-5.8S-ITS2) of the rDNA, and part of the ß-tubulin and translation elongation factor 1-α genes, revealed five different black foot fungi occurring in declining young vines in BC, namely Cylindrocarpon pauciseptatum, Ilyonectria liriodendri, Ilyonectria macrodidyma, Ilyonectria robusta, and Ilyonectria torresensis. Pathogenicity studies showed all five species to be highly virulent in the grapevine rootstock cultivar 3309C. Overall, I. liriodendri and I. macrodidyma were the most virulent species when inoculated in Vitis vinifera 'Chardonnay' and rootstock 3309C.

3.
Plant Dis ; 98(4): 469-482, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30708729

RESUMO

Esca and Petri disease are two economically important grapevine diseases worldwide. This study reports for the first time the occurrence of both diseases on grapevines in British Columbia (BC) and subsequently in Canada. Visual assessment of 55,699 vines in 118 vineyards revealed a low incidence of esca with only 104 (0.2%) vines showing foliar symptoms. Young vine decline (YVD) was observed in 1,910 (7.8%) of 24,487 monitored young vines and in 52 (8%) of 654 young vines used as re-plants in mature vineyards. In 8 of 51 monitored young vineyards, YVD-affected vines ranged between 15 and 55%. Morphological studies along with DNA analyses of the ITS1-5.8S-ITS2, and part of the ß-tubulin, actin, and translation elongation factor 1-α gene regions, allowed us to identify Cadophora luteoolivacea, Phaeomoniella chlamydospora, Phaeoacremonium iranianum, Togninia fraxinopennsylvanica, Togninia minima, and the novel species Phaeoacremonium canadense and Phaeoacremonium roseum from esca and Petri disease infected vines in BC. This study includes for the first time the EF1-α DNA marker in Phaeoacremonium spp. delineation. Pathogenicity studies showed all seven fungi to cause vascular symptoms similar to those observed in esca and Petri disease infected vines. Additionally, the "tiger-stripes" foliar symptom of esca was successfully reproduced when healthy potted vines were inoculated with BC isolates of Pa. chlamydospora, Pm. canadense, Pm. iranianum, T. fraxinopennsylvanica, and T. minima.

4.
Bioact Mater ; 10: 222-235, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34901541

RESUMO

ß-Tricalcium Phosphate (ß-TCP), one of the most used bone graft substitutes, may contain up to 5 wt% foreign phase according to standards. Typical foreign phases include ß-calcium pyrophosphate (ß-CPP) and hydroxyapatite (HA). Currently, the effect of small amounts of impurities on ß-TCP resorption is unknown. This is surprising since pyrophosphate is a very potent osteoclast inhibitor. The main aim of this study was to assess the effect of small ß-CPP fractions (<1 wt%) on the in vitro osteoclastic resorption of ß-TCP. A minor aim was to examine the effect of ß-CPP and HA impurities on the physico-chemical properties of ß-TCP powders and sintered cylinders. Twenty-six batches of ß-TCP powder were produced with a Ca/P molar ratio varying between 1.440 and 1.550. Fifteen were further processed to obtain dense and polished ß-TCP cylinders. Finally, six of them, with a Ca/P molar ratio varying between 1.496 (1 wt% ß-CPP) and 1.502 (1 wt% HA), were incubated in the presence of osteoclasts. Resorption was quantified by white-light interferometry. Osteoclastic resorption was significantly inhibited by ß-CPP fraction in a linear manner. The presence of 1% ß-CPP reduced ß-TCP resorption by 40%, which underlines the importance of controlling ß-CPP content when assessing ß-TCP biological performance.

5.
Int J Comput Assist Radiol Surg ; 16(3): 375-386, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33484431

RESUMO

PURPOSE: Intensity-based image registration has been proven essential in many applications accredited to its unparalleled ability to resolve image misalignments. However, long registration time for image realignment prohibits its use in intra-operative navigation systems. There has been much work on accelerating the registration process by improving the algorithm's robustness, but the innate computation required by the registration algorithm has been unresolved. METHODS: Intensity-based registration methods involve operations with high arithmetic load and memory access demand, which supposes to be reduced by graphics processing units (GPUs). Although GPUs are widespread and affordable, there is a lack of open-source GPU implementations optimized for non-rigid image registration. This paper demonstrates performance-aware programming techniques, which involves systematic exploitation of GPU features, by implementing the diffeomorphic log-demons algorithm. RESULTS: By resolving the pinpointed computation bottlenecks on GPU, our implementation of diffeomorphic log-demons on Nvidia GTX Titan X GPU has achieved ~ 95 times speed-up compared to the CPU and registered a 1.3-M voxel image in 286 ms. Even for large 37-M voxel images, our implementation is able to register in 8.56 s, which attained ~ 258 times speed-up. Our solution involves effective employment of GPU computation units, memory, and data bandwidth to resolve computation bottlenecks. CONCLUSION: The computation bottlenecks in diffeomorphic log-demons are pinpointed, analyzed, and resolved using various GPU performance-aware programming techniques. The proposed fast computation on basic image operations not only enhances the computation of diffeomorphic log-demons, but is also potentially extended to speed up many other intensity-based approaches. Our implementation is open-source on GitHub at https://bit.ly/2PYZxQz .


Assuntos
Gráficos por Computador , Processamento de Imagem Assistida por Computador/métodos , Monitorização Intraoperatória/instrumentação , Algoritmos , Humanos , Monitorização Intraoperatória/métodos , Distribuição Normal , Linguagens de Programação , Reprodutibilidade dos Testes , Software
6.
Am J Transplant ; 10(9): 2082-91, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20883542

RESUMO

Islet transplantation is an experimental therapy for selected patients with type 1 diabetes (T1DM). It remains limited by immunosuppressive drug toxicity, progressive loss of insulin independence, allosensitization and the need for multiple islet donors. We describe our experience with an efalizumab-based immunosuppressive regimen as compared to the prevailing standard regimen, the Edmonton protocol. Twelve patients with T1DM received islet transplants: eight were treated with the Edmonton protocol; four were treated with daclizumab induction, a 6-month course of tacrolimus, and maintenance with efalizumab and mycophenolate mofetil. The primary endpoint was insulin independence after one islet infusion. Only two Edmonton protocol treated patients achieved the primary endpoint; six required islets from multiple donors, and all experienced leukopenia, mouth ulcers, anemia, diarrhea and hypertransaminasemia. Four became allosensitized. All patients treated with the efalizumab-based regimen achieved insulin independence with normal hemoglobin A1c after a single islet cell infusion and remained insulin independent while on efalizumab. These patients experienced significantly fewer side effects and none became allosensitized. Trial continuation was terminated by withdrawal of efalizumab from the market. These data suggest that this efalizumab-based regimen prevents islet rejection, is well tolerated, and allows for single donor islet transplantation.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/cirurgia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Transplante das Ilhotas Pancreáticas/efeitos adversos , Doadores de Tecidos , Adulto , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Daclizumabe , Diabetes Mellitus Tipo 1/metabolismo , Estudos de Viabilidade , Humanos , Imunoglobulina G/efeitos adversos , Imunoglobulina G/uso terapêutico , Imunossupressores/efeitos adversos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
7.
Rev Sci Instrum ; 91(5): 053501, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32486748

RESUMO

We designed and built a diagnostic based on a cathodoluminescent screen for the detection of turbulent plasma structures with high spatial resolution. The screen is coated with a low threshold energy cathodoluminescent powder that emits light when exposed to a plasma. The emitted light is imaged with a fast frame camera combined with an image intensifier and an optical bandpass filter. The diagnostic is used to study turbulent structures and seeded blobs. The results are analyzed with pattern recognition algorithms to track the turbulent structures and study their evolution in time.

8.
Colloids Surf B Biointerfaces ; 171: 445-450, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30075420

RESUMO

Fluorinated-titanium dioxide (TiO2-F) nanoparticles in a pure anatase polymorph was precipitated from solution by hydrolysis of titanium oxychloride, using urea and ammonia as precipitation agents and potassium fluoride as a source of fluorine anion. A further wet attrition milling in presence of glycine completed by a heat treatment allowed an additional nitrogen doping of TiO2 (TiO2-F&N-HT). The morphology and crystalline structure of the as-synthesized powder was determined by transmission electron microscopy (TEM) and X-ray diffraction (XRD) and showed that TiO2 powder was composed of nanoparticles with narrow size distribution which crystallized in the anatase phase. X-ray photoelectron spectroscopy (XPS) revealed that fluorine and nitrogen are present in TiO2 as surface fluorination and interstitial doping, respectively. UV-vis diffuse reflectance spectroscopy (DRS) showed an increased optical absorption in the visible for TiO2-F&N-HT sample. Under visible light irradiation, TiO2-F nanoparticles showed a high photocatalytic performance, showing the high potential of an improved surface fluorination for Escherichia coli (E. coli) disinfection in suspension. These results show the importance of anatase-TiO2 nanoparticles synthesis and modification by using a wet chemical approach leading to low aggregation and high specific surface area for effective bacterial inactivation. The co-doped TiO2-F&N-HT powder showed slightly improved performance compared to the fluorinated sample. The significant degree of aggregation after the heat treatment is postulated as being a limiting factor in its photocatalytic activity.


Assuntos
Antibacterianos/química , Luz , Nanopartículas/química , Titânio/química , Antibacterianos/farmacologia , Catálise , Escherichia coli/efeitos dos fármacos , Halogenação , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície , Titânio/farmacologia
9.
J Natl Cancer Inst ; 86(6): 455-60, 1994 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-8120921

RESUMO

BACKGROUND: Body iron stores and dietary iron intake have both been shown to be positively associated with subsequent risk of colon cancer. This finding comes from a cohort study involving 14,000 men, but the positive association occurred in only 12 cases. PURPOSE: We performed a case-control study of 264 men and 98 women to test for an association between serum ferritin levels and the presence of adenoma of the colon that would be independent of other known risk factors. METHODS: Serum ferritin levels were determined in this study from sera, frozen at -80 degrees C for 5-8 years, that had been originally obtained between 1984-1987 at the Walter Reed Army Medical Center from adult male and postmenopausal female patients undergoing routine colonoscopic examination and previously enrolled in a case-control study that assessed the potential dietary and environmental risk factors for colonic neoplasia. The presence of fecal occult blood in the stool or the suggestion of colonic polyps seen on barium enema defined eligibility for the study. Patients with known preexisting colonic disease were excluded. Eligible patients had their blood drawn and serum prepared. Following colonoscopy and histologic review, the patients were classified into three groups: normal (without neoplastic disease), 159 subjects; adenoma, 145 subjects; and colon cancer, 29 subjects. Body iron stores were determined by measuring serum ferritin levels by a competitive-binding radiometric immunoassay. Ferritin levels categorized into quintiles for adenoma were defined. Crude and adjusted odds ratios (ORadj) with 95% confidence intervals (CIs) for cancer and adenoma related to ferritin were calculated, controlling for known or suspected risk factors including sex, age, race, body mass index, family history, tobacco use, and alcohol consumption. RESULTS: Statistically significant associations of adenoma risk were seen in the third ([ORadj] = 3.8; 95% CI = 1.5-9.5) and fourth (ORadj = 5.1; 95% CI = 2.0-12.7) quintiles of ferritin relative to the first quintile, for smoking history (ORadj = 2.4; 95% CI = 1.3-4.3), for male sex (ORadj = 1.9; 95% CI = 1.0-3.7), and for family history of polyps or cancer (ORadj = 1.8; 95% CI = 1.0-3.4). From a second set of analyses that excluded 36 patients with serum ferritin of greater than or equal to 399 ng/mL, the greatest effect of ferritin on adenoma risk by anatomic subsite was seen in the right colon. CONCLUSION: The apparent dose-response for serum ferritin level and adenoma risk suggest that exposure to iron may be related to adenoma formation.


Assuntos
Adenoma/sangue , Neoplasias do Colo/sangue , Ferritinas/sangue , Ferro/metabolismo , Adenoma/etiologia , Adulto , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Neoplasias do Colo/etiologia , Feminino , Humanos , Masculino , Fatores de Risco
10.
J Natl Cancer Inst ; 87(23): 1781-7, 1995 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-7473835

RESUMO

BACKGROUND: Epidemiologic studies have shown that consuming foods containing beta-carotene is associated with a decreased incidence of colon cancer. The validity of this association has recently been questioned. It is not known if the rate of colonic cell proliferation differs among individuals with or without a history of colonic polyps or cancer and if proliferation changes in response to beta-carotene. PURPOSE: This study was intended to (a) determine whether differences exist in colonic cell proliferation in individuals with and without prior colonic polyps or tumors, (b) demonstrate that beta-carotene accumulates in colonic mucosa following dietary supplementation, and (c) determine whether mucosal beta-carotene accumulation influences colonic cell proliferation. METHODS: Subjects were enrolled in the phase I study from June 1991 until February 1994. The participants included 20 individuals (11 males and nine females, aged 62.3 +/- 8.9 years [means +/- SD]) with normal colons (as judged by recent colonoscopy), 40 (24 males and 16 females, aged 59.6 +/- 10.1 years) with a history of colonic polyp(s), and 41 (30 males and 11 females, aged 67.2 +/- 9.7 years) with prior colon cancer. The subjects in the last two groups consumed either 30 mg of beta-carotene or placebo each morning for 3 months. This dose of beta-carotene has no known toxic effects, but it can increase the serum level by approximately 10-fold. beta-carotene concentration in serum and colonic tissue was quantitated by high-pressure liquid chromatography in samples collected before and after supplementation with beta-carotene or placebo. Cellular proliferation was assessed on the basis of tissue ornithine decarboxylase activity, urinary polyamine excretion, and proliferating cell nuclear antigen expression. The differences in colonic cell proliferation parameters due to beta-carotene supplementation, within and among different groups, were evaluated by the Wilcoxon matched-pairs signed ranked test and the Mann-Whitney test, respectively. All statistical tests were two-sided. RESULTS: Colonic cell proliferation did not differ in samples obtained from individuals with and without prior colonic polyp(s) or cancer. beta-carotene concentrations in serum and colonic tissue were significantly increased in groups receiving beta-carotene (P < .001). However, cell proliferation did not differ, as judged by any of the three measures, among samples from all experimental groups collected before and after supplementation with beta-carotene. CONCLUSIONS: Dietary supplementation with beta-carotene for a period of 3 months does not alter colonic cell proliferation in individuals with a history of colonic polyps or cancer. IMPLICATIONS: The mechanism by which beta-carotene might reduce colon cancer incidence does not appear to involve or result in a change in cell proliferation in the normal colonic mucosa as studied in individuals with a history of colonic polyps or cancer.


Assuntos
Carotenoides/administração & dosagem , Colo/citologia , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carotenoides/metabolismo , Divisão Celular/efeitos dos fármacos , Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ornitina Descarboxilase/metabolismo , Antígeno Nuclear de Célula em Proliferação/análise , beta Caroteno
11.
J Natl Cancer Inst ; 93(24): 1872-9, 2001 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11752012

RESUMO

BACKGROUND: Human prostate tissues are vulnerable to oxidative DNA damage. The risk of prostate cancer is lower in men reporting higher consumption of tomato products, which contain high levels of the antioxidant lycopene. We examined the effects of consumption of tomato sauce-based pasta dishes on lycopene uptake, oxidative DNA damage, and prostate-specific antigen (PSA) levels in patients already diagnosed with prostate cancer. METHODS: Thirty-two patients with localized prostate adenocarcinoma consumed tomato sauce-based pasta dishes for the 3 weeks (30 mg of lycopene per day) preceding their scheduled radical prostatectomy. Serum and prostate lycopene concentrations, serum PSA levels, and leukocyte DNA oxidative damage (ratio of 8-hydroxy-2'-deoxyguanosine [8-OHdG] to 2'-deoxyguanosine [dG]) were assessed before and after the dietary intervention. DNA oxidative damage was assessed in resected prostate tissue from study participants and from seven randomly selected prostate cancer patients. All statistical tests were two-sided. RESULTS: After the dietary intervention, serum and prostate lycopene concentrations were statistically significantly increased, from 638 nM (95% confidence interval [CI] = 512 to 764 nM) to 1258 nM (95% CI = 1061 to 1455 nM) (P<.001) and from 0.28 nmol/g (95% CI = 0.18 to 0.37 nmol/g) to 0.82 nmol/g (95% CI = 0.57 to 1.11 nmol/g) (P <.001), respectively. Compared with preintervention levels, leukocyte oxidative DNA damage was statistically significantly reduced after the intervention, from 0.61 8-OHdG/10(5) dG (95% CI = 0.45 to 0.77 8-OHdG/10(5) dG) to 0.48 8-OHdG/ 10(5) dG (95% CI = 0.41 to 0.56 8-OHdG/10(5) dG) (P =.005). Furthermore, prostate tissue oxidative DNA damage was also statistically significantly lower in men who had the intervention (0.76 8-OHdG/10(5) dG [95% CI = 0.55 to 0.96 8-OHdG/10(5) dG]) than in the randomly selected patients (1.06 8-OHdG/10(5) dG [95% CI = 0.62 to 1.51 8-OHdG/10(5) dG]; P =.03). Serum PSA levels decreased after the intervention, from 10.9 ng/mL (95% CI = 8.7 to 13.2 ng/mL) to 8.7 ng/mL (95% CI = 6.8 to 10.6 ng/mL) (P<.001). CONCLUSION: These data indicate a possible role for a tomato sauce constituent, possibly lycopene, in the treatment of prostate cancer and warrant further testing with a larger sample of patients, including a control group.


Assuntos
Adenocarcinoma/terapia , Dano ao DNA , Desoxiguanosina/análogos & derivados , Dietoterapia , Estresse Oxidativo , Neoplasias da Próstata/terapia , Solanum lycopersicum , 8-Hidroxi-2'-Desoxiguanosina , Fatores Etários , Idoso , Carotenoides/biossíntese , Carotenoides/sangue , Cromatografia Líquida de Alta Pressão , DNA/metabolismo , Desoxiguanosina/biossíntese , Desoxiguanosina/metabolismo , Eletroquímica , Humanos , Leucócitos/metabolismo , Licopeno , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo , Próstata/metabolismo , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/metabolismo , Fatores de Tempo
12.
Cancer Res ; 53(16): 3723-5, 1993 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8339282

RESUMO

Colonic adenocarcinoma affects approximately 6% of adults in many Western countries. beta-Carotene (BC), a safe, inexpensive, and widely available compound, has been proposed as a cancer chemopreventive agent. To evaluate whether BC shows promise as an inhibitor of colonic carcinogenesis, we studied 20 male subjects who had previously undergone resection of colonic adenocarcinoma. Each subject received beta-carotene, 30 mg orally, daily for 6 months. Rectal mucosa was sampled at multiple intervals prior to, during, and following BC administration. Mucosal ornithine decarboxylase (ODC) activity and serum and mucosal BC concentrations were determined at each interval. ODC activity was inhibited by 44% (P < 0.05) and 57% (P < 0.01) after 2 and 9 weeks, respectively, of BC administration and remained low compared with baseline even 6 months following discontinuation of BC. Serum and mucosal BC concentrations increased as expected during BC administration and remained elevated for 6 months following BC discontinuation. The demonstrated inhibition of rectal mucosal ODC activity in these patients with resected colon cancer suggests that BC may prove useful as a cancer chemopreventive agent.


Assuntos
Carotenoides/farmacologia , Neoplasias do Colo , Inibidores da Ornitina Descarboxilase , Reto/enzimologia , Reto/patologia , Idoso , Humanos , Mucosa Intestinal/enzimologia , Masculino , Pessoa de Meia-Idade , Ornitina Descarboxilase/metabolismo , Estudos Prospectivos , beta Caroteno
13.
Biochim Biophys Acta ; 1180(2): 147-62, 1992 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-1463766

RESUMO

Competition between the (n - 3) and (n - 6) types of highly unsaturated fatty acids can diminish the abundance of (n - 6) eicosanoid precursors in a tissue, which in turn can diminish the intensity of tissue responses that are mediated by (n - 6) eicosanoids. The mixture of 20- and 22-carbon highly unsaturated fatty acids maintained in the phospholipids of human plasma is related to the dietary intake of 18:2 (n - 6) and 18:3 (n - 3) by empirical hyperbolic equations in a manner very similar to the relationship reported for laboratory rats (Lands, W.E.M., Morris, A. and Libelt, B. (1990) Lipids 25, 505-516). Analytical results from volunteers ingesting self-selected diets showed an inter-individual variance for the proportion of (n - 6) eicosanoid precursors in the fatty acids of plasma phospholipids of about 5%, but the variance among multiple samples taken from the same individual throughout the day was less (about 3%), closer to the experimental variance of the analytical procedure (about 1%). The reproducibility of the results makes it likely that analysis of fatty-acid composition of plasma lipids from individuals will prove useful in estimating the diet-related tendency for severe thrombotic, arthritic or other disorders that are mediated by (n - 6) eicosanoids. Additional constants and terms were included in the equations to account for the effects of 20- and 22-carbon highly unsaturated (n - 3) fatty acids in the diet. A lower constant for the 20- and 22-carbon (n - 3) fatty acids compared to that for the 18-carbon (n - 3) fatty acid in decreasing the ability of dietary 18:2 (n - 6) to maintain 20:4 (n - 6) in tissue lipids confirmed the greater competitive effectiveness of the more highly unsaturated n - 3 fatty acids in the elongation/desaturation process. Also, a lower constant for direct incorporation of 20-carbon fatty acids of the n - 6 vs. the n - 3 type indicated a greater competitive effectiveness of 20:4 (n - 6) relative to 20:5 (n - 3) in reesterification after release from tissue lipids. The equations may be used in reverse to estimate the dietary intakes of the (n - 3) and (n - 6) fatty acids by using the composition of the fatty acids that had been maintained in plasma lipids.


Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Insaturados/análise , Fosfolipídeos/sangue , Idoso , Ácidos Graxos Ômega-6 , Feminino , Humanos , Hiperlipidemias/dietoterapia , Masculino , Matemática , Inquéritos e Questionários , Triglicerídeos/sangue
14.
Arch Intern Med ; 143(5): 913-5, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6679236

RESUMO

We examined two middle-aged male cousins with unexplained edema of postpubertal onset involving the upper and lower limbs, face, and larynx and, in one of them, a persistent pleural effusion. Scintilymphangiography detected an apparent paucity or absence of lymph nodes in the axillae and above the inguinal ligaments, indicating a defect in the lymphatic systems. Laryngeal edema, confirmed endoscopically, produced changes in one of them in the flow volume loop characteristic of a variable extrathoracic obstruction. A family study showed autosomal dominant transmission of the disorder. The nosology of late-onset lymphedema is briefly discussed, with particular reference to the so-called yellow nail syndrome.


Assuntos
Edema Laríngeo/complicações , Linfedema/genética , Derrame Pleural/complicações , Adulto , Idoso , Feminino , Fluxo Expiratório Forçado , Humanos , Edema Laríngeo/fisiopatologia , Linfedema/complicações , Linfedema/diagnóstico , Linfedema/fisiopatologia , Masculino , Pessoa de Meia-Idade , Linhagem , Derrame Pleural/fisiopatologia , Fumar , Capacidade Vital
15.
Free Radic Biol Med ; 26(5-6): 695-703, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10218659

RESUMO

DNA 8-hydroxy-2'-deoxyguanosine (8-OHdG) is a promising biomarker for oxidative damage. We assessed its responsiveness to diet in 32 nonsmoking, healthy subjects (12 male, 20 female) aged 31+/-7.6 years. They consumed two liquid formula diets (Ensures) as the sole source of nutrition for 10-d in a randomized crossover design, with 5-d control solid food diets as washout before each liquid diet period. Reformulated Ensure (Re-En) had a vitamin E/ PUFA of 3.5 compared to standard Ensure (En) of 1.1. We hypothesized that subjects would have lower leukocyte 8-OHdG/deoxyguanosine (dG) ratios while consuming Re-En compared to En. But 8-OHdG/dG ratios did not change with the consumption of either Re-En or En. The mean ratios of 8-OHdG/dG after 10 days of Re-En and En consumption were (2.12+/-0.68)x10(-5) and (2.16+/-0.63)x10(-5), respectively. However, there was a 22% decrease in 8-OHdG/dG by the end of the study and a significant downward trend of leukocyte 8-OHdG among all subjects throughout all nutrient-rich diet phases as the study progressed (Test for trend: p = .04; paired t-test: p = .07). Because all the experimental diets provided antioxidant nutrients at higher quantities than typically consumed by a U.S. age-matched population, this study adds to the few in vivo studies that show a decrease in DNA damage in healthy nonsmoking subjects through dietary intervention.


Assuntos
Dano ao DNA , DNA/sangue , Gorduras Insaturadas na Dieta , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/farmacologia , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Biomarcadores/sangue , Estudos Cross-Over , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Sacarose Alimentar , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Alimentos Formulados , Humanos , Leucócitos/efeitos dos fármacos , Masculino , Análise de Regressão , Fatores de Tempo , Vitamina E/administração & dosagem
16.
Am J Clin Nutr ; 62(6 Suppl): 1403S-1409S, 1995 12.
Artigo em Inglês | MEDLINE | ID: mdl-7495238

RESUMO

Evidence from intervention trials with vitamins E and C and beta-carotene are reviewed as well as evidence from trials that have used intermediate endpoints with a special emphasis on biomarkers of cancer of the colorectum. The methodologic issues that require resolution before a second generation of clinical trials are launched to assess the efficacy of these antioxidants in the prevention of cancer are identified. Specific concerns regarding the validation of pathologic biomarkers of cancer and biochemical markers of mechanism of action for the antioxidants are discussed. Cellular proliferation indexes in the colon are used as an example of pathologic biomarkers for cancer and the measurement of plasma and tissue malondialdehyde concentrations is used as an example of problems with the development of biochemical markers of oxidative stress that can be used in prevention trials. The use of DNA oxidation products as promising biomarkers is also discussed.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Biomarcadores Tumorais , Carotenoides/administração & dosagem , Neoplasias/prevenção & controle , Vitamina E/administração & dosagem , Ensaios Clínicos como Assunto , Humanos , Estresse Oxidativo , beta Caroteno
17.
Am J Clin Nutr ; 48(2): 305-11, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2841841

RESUMO

The effect of a nutritionally complete liquid-formula diet without soy polysaccharide or with the fiber source at 20, 30, or 40 g/d on mineral retention in young men was examined. Addition of 20 g soy polysaccharide to the liquid formula significantly (p less than 0.05) improved the retentions of copper, iron, zinc, and magnesium over the diet without added fiber. The highest level of soy polysaccharide (40 g/d) resulted in significantly (p less than 0.05) lower Cu, Zn, Fe, and Mg retentions than did the 20-g diet and the 30-g diet had an intermediate effect. Except for slightly negative Cu (-0.1 +/- 0.4 mg) and Fe (-0.6 +/- 3.7 mg) retentions on the 40-g diet, retentions of all minerals remained positive throughout this study. The liquid-formula diet supplemented with 40 g soy polysaccharide could have a deleterious effect on mineral retentions in persons consuming the diet as their sole nutritional source.


Assuntos
Fibras na Dieta/metabolismo , Minerais/metabolismo , Cálcio/metabolismo , Cobre/metabolismo , Alimentos Formulados , Humanos , Ferro/metabolismo , Magnésio/metabolismo , Masculino , Fósforo/metabolismo , Potássio/metabolismo , Glycine max , Zinco/metabolismo
18.
Am J Clin Nutr ; 58(1): 91-7, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8317396

RESUMO

Anthropometric measurements were taken on 281 toddlers (24-48 mo old) in Linguère, Sénégal, to determine the prevalence of undernutrition. Blood samples collected from 271 of the toddlers were analyzed for retinol and carotenoids by HPLC. According to the National Center for Health Statistics reference values 30.2% of the population was undernourished. Serum retinol values were below the lower limit of the normal range in 71.5% of the children; 7.4% of this group had concentrations < 0.35 mumol/L, placing them at risk for xerophthalmia. Only 3% of the population had serum retinol values > or = 1.0 mumol/L. Serum carotenoids were low (< 0.70 mumol/L) in 55% of the children. Retinol-binding protein values were low and measurable concentrations of retinyl palmitate were detectable in only 17% of the children. Undernutrition and poor vitamin A status were found to exist at a concentration that would endanger health.


Assuntos
Transtornos da Nutrição Infantil/epidemiologia , Distúrbios Nutricionais/epidemiologia , Deficiência de Vitamina A/epidemiologia , Antropometria , Análise Química do Sangue , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Senegal/epidemiologia
19.
Am J Clin Nutr ; 54(2): 304-10, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1858694

RESUMO

The effects of a 20%-fat diet (LF) on total body weight, lean body weight, and adiposity were studied in 18 premenopausal women with body mass index (BMI) of 18-44. Subjects were fed a 37%-fat (HF) control diet for 4 wk followed by the LF diet for 20 wk. Total body weight, lean body weight, and fat weight were measured at the end of the HF and LF dietary periods by hydrostatic weighing. Despite adjustments in energy intake to maintain weight throughout the study, subjects exhibited a 2.8% decrease in total body weight (P less than 0.0006), an 11.3% decrease in fat weight (P less than 0.0001), and a 2.2% increase in lean body weight (P less than 0.0149) by the end of the LF period. Similar changes were observed in obese (BMI greater than 30) and non-obese women (BMI less than 30). By the end of the LF period, energy intake had increased significantly in comparison with the HF diet (119% of the HF intake, P less than 0.0001). Results could not be explained by changes in daily activity levels and suggest that macronutrient composition plays a role in energy requirements for weight maintenance.


Assuntos
Composição Corporal , Peso Corporal , Gorduras na Dieta/administração & dosagem , Ingestão de Energia , Tecido Adiposo/anatomia & histologia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/patologia , Obesidade/fisiopatologia
20.
Am J Clin Nutr ; 55(2): 381-4, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1734675

RESUMO

In vitro studies suggest that insulin-like growth factor I (IGF-I) may modulate hepatic production and peripheral utilization of lipoproteins. We measured blood concentrations of IGF-I; total, high-density-lipoprotein, and low-density-lipoprotein (LDL) cholesterol; and apolipoproteins in 18 women with above average cholesterol after high- and low-fat diet periods. Total cholesterol fell 6% (P less than 0.02) during the low-fat diet because of reduced concentrations of LDL cholesterol (P less than 0.01). Serum concentrations of IGF-I were inversely correlated with total and LDL cholesterol and apolipoprotein B during both high-fat (r = -0.676, P less than 0.005; r = -0.745, P less than 0.001; and r = -0.504, P less than 0.04, respectively) and low-fat (r = -0.656, P less than 0.005; r = -0.757, P less than 0.001; and r = -0.695, P less than 0.001, respectively) diets. IGF-I increased with reduced fat intake in obese subjects only. Thus, IGF-I may contribute to the regulation of LDL cholesterol in mildly hypercholesterolemic women but may not mediate the beneficial response to reduced fat intake.


Assuntos
LDL-Colesterol/sangue , Gorduras na Dieta/administração & dosagem , Fator de Crescimento Insulin-Like I/análise , Adulto , Apolipoproteínas/sangue , Índice de Massa Corporal , Colesterol/sangue , HDL-Colesterol/sangue , Gorduras na Dieta/farmacologia , Feminino , Humanos , Concentração Osmolar
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