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1.
Diabet Med ; 31(10): 1230-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24750373

RESUMO

AIM: To investigate the race-specific trend in attainment of the American Diabetes Association cardiovascular risk factor control goals (HbA1c <53 mmol/mol (7.0%), blood pressure <130/80 mmHg and LDL cholesterol <2.6mmol/l) by patients with Type 2 diabetes. METHODS: The study sample included 14 946 African-American and 12 758 white patients who were newly diagnosed with Type 2 diabetes between 2001 and 2009 in the Louisiana State University Hospital system. The race-specific percentages of patients' attainment of American Diabetes Association goals were calculated using the baseline and follow-up measurements of HbA1c , blood pressure, and LDL cholesterol levels. Logistic regression was used to test the difference between African-American and white patients. RESULTS: The percentage of patients who met all three American Diabetes Association goals increased from 8.2% in 2001 to 10.2% in 2009 (increased by 24.4%) in this cohort. Compared with African-American patients, white patients had better attainment of the following American Diabetes Association goals: HbA1c (61.4 vs. 55.1%), blood pressure (25.8 vs. 20.4%), LDL cholesterol (40.1 vs. 37.7%) and all three goals (7.3 vs. 5.1%). African-American and white patients generally had a better cardiovascular disease risk factor profile during follow-up when we assessed attainment of the American Diabetes Association goals by means of HbA1c , blood pressure and LDL cholesterol. CONCLUSIONS: During 2001-2009, the present low-income cohort of people with Type 2 diabetes generally experienced improved control of cardiovascular disease risk factors. White patients had better attainment of the American Diabetes Association cardiovascular risk factor control goals than their African-American counterparts.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/terapia , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Disparidades em Assistência à Saúde , Pessoas sem Cobertura de Seguro de Saúde , Adulto , Negro ou Afro-Americano , Idoso , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etnologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/economia , Diabetes Mellitus Tipo 2/etnologia , Angiopatias Diabéticas/economia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/etnologia , Cardiomiopatias Diabéticas/economia , Cardiomiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/etnologia , Feminino , Disparidades em Assistência à Saúde/economia , Disparidades em Assistência à Saúde/etnologia , Hospitais Estaduais , Hospitais Universitários , Humanos , Estudos Longitudinais , Louisiana/epidemiologia , Masculino , Pessoas sem Cobertura de Seguro de Saúde/etnologia , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , População Branca
2.
Int J Obes (Lond) ; 36(3): 448-55, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21946707

RESUMO

BACKGROUND: Weight loss reduces energy expenditure, but the contribution of different macronutrients to this change is unclear. HYPOTHESIS: We tested the hypothesis that macronutrient composition of the diet might affect the partitioning of energy expenditure during weight loss. DESIGN: A substudy of 99 participants from the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial had total energy expenditure (TEE) measured by doubly labeled water, and resting energy expenditure (REE) measured by indirect calorimetry at baseline and repeated at 6 months in 89 participants. Participants were randomly assigned to one of four diets with either 15 or 25% protein and 20 or 40% fat. RESULTS: TEE and REE were positively correlated with each other and with fat-free mass and body fat, at baseline and 6 months. The average weight loss of 8.1 ± 0.65 kg (least-square mean ± s.e.) reduced TEE by 120 ± 56 kcal per day and REE by 136 ± 18 kcal per day. A greater weight loss at 6 months was associated with a greater decrease in TEE and REE. Participants eating the high-fat diet (HF) lost significantly more fat-free mass (1.52 ± 0.55 kg) than the low-fat (LF) diet group (P<0.05). Participants eating the LF diet had significantly higher measures of physical activity than the HF group. CONCLUSION: A greater weight loss was associated with a larger decrease in both TEE and REE. The LF diet was associated with significant changes in fat-free body mass and energy expenditure from physical activity compared with the HF diet.


Assuntos
Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Metabolismo Energético , Obesidade/dietoterapia , Adulto , Idoso , Distribuição da Gordura Corporal , Feminino , Humanos , Los Angeles/epidemiologia , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/fisiopatologia , Descanso , Redução de Peso
3.
Eat Weight Disord ; 17(2): e101-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23010779

RESUMO

Few well-controlled trials have evaluated the effects that macronutrient composition has on changes in food cravings during weight loss treatment. The present study, which was part of the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial, investigated whether the fat and protein content of four different diets affected changes in specific food cravings in overweight and obese adults. A sample of 811 adults were recruited across two clinical sites, and each participant was randomly assigned to one of four macronutrient prescriptions: 1) low fat (20% of energy), average protein (15% of energy); 2) moderate fat (40%), average protein (15%); 3) low fat (20%), high protein (25%); 4) moderate fat (40%), high protein (25%). With few exceptions, the type of diet that participants were assigned did not differentially affect changes in specific food cravings. Participants assigned to the high-fat diets, however, had reduced cravings for carbohydrates at month 12 (p<0.05) and fruits and vegetables at month 24. Also, participants assigned to high-protein diets had increased cravings for sweets at month 6 and month 12 (ps<0.05). Participants in all four dietary conditions reported significant reductions in food cravings for specific types of foods (i.e., high fat foods, fast food fats, sweets, and carbohydrates/starches; all ps<0.05). Cravings for fruits and vegetables, however, were increased at month 24 (p<0.05). Calorically restricted diets (regardless of their macronutrient composition) yielded significant reductions in cravings for fats, sweets, and starches whereas cravings for fruits and vegetables were increased.


Assuntos
Restrição Calórica , Dieta Redutora , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Preferências Alimentares , Sobrepeso/dietoterapia , Redução de Peso , Adulto , Fatores Etários , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Proteínas Alimentares/administração & dosagem , Comportamento Alimentar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia , Autorrelato , Fatores Sexuais , Inquéritos e Questionários , Resultado do Tratamento
4.
Nat Commun ; 12(1): 999, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579928

RESUMO

Knowledge of magnetic symmetry is vital for exploiting nontrivial surface states of magnetic topological materials. EuIn2As2 is an excellent example, as it is predicted to have collinear antiferromagnetic order where the magnetic moment direction determines either a topological-crystalline-insulator phase supporting axion electrodynamics or a higher-order-topological-insulator phase with chiral hinge states. Here, we use neutron diffraction, symmetry analysis, and density functional theory results to demonstrate that EuIn2As2 actually exhibits low-symmetry helical antiferromagnetic order which makes it a stoichiometric magnetic topological-crystalline axion insulator protected by the combination of a 180∘ rotation and time-reversal symmetries: [Formula: see text]. Surfaces protected by [Formula: see text] are expected to have an exotic gapless Dirac cone which is unpinned to specific crystal momenta. All other surfaces have gapped Dirac cones and exhibit half-integer quantum anomalous Hall conductivity. We predict that the direction of a modest applied magnetic field of µ0H ≈ 1 to 2 T can tune between gapless and gapped surface states.

5.
J Exp Med ; 163(4): 826-36, 1986 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-3005468

RESUMO

We describe a newly recognized 40 kD FcR for IgG on human neutrophilic granulocytes. An mAb (IV3) developed against the IgG FcR of K562 cells, and specific as well for a 40 kD FcR on human monocytes and platelets, was found to purify by affinity adsorption a 40 kD protein from detergent lysates of surface-radioiodinated neutrophils. This protein, proteolytically degraded to 33 kD when purified in the absence of diisopropylfluorophosphate, is distinct from the 51-73 kD protein precipitated by the anti-neutrophil FcR mAb, 3G8, previously described by others. Complete inhibition of binding of rabbit IgG-coated erythrocytes to neutrophils was achieved only when both antibodies, IV3 and 3G8, were used. Fab fragments of IV3 were as effective inhibitors as the intact molecule. IV3 IgG or Fab fragments completely and selectively inhibited immune complex-mediated generation of superoxide by human neutrophils; superoxide generation by other stimulants was not abrogated by IV3. This antibody (IV3) bound also to human eosinophils and completely inhibited the binding of IgG-coated erythrocytes to eosinophils. IV3 appears to define the human homolog of the murine macrophage FcRII identified initially by mAb 2.4G2 and present in the mouse on both neutrophils and eosinophils.


Assuntos
Imunoglobulina G/análise , Neutrófilos/metabolismo , Receptores Fc/análise , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo , Eosinófilos/metabolismo , Citometria de Fluxo , Humanos , Fragmentos Fab das Imunoglobulinas/farmacologia , Formação de Roseta , Superóxidos/metabolismo
7.
J Phys Condens Matter ; 21(12): 124201, 2009 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21817443

RESUMO

Natural gadolinium is the strongest neutron-absorbing element and neutron diffraction studies of Gd-containing materials rely on the use of either enriched Gd isotopes or short neutron wavelengths where the absorption is weaker but, unfortunately, the neutron flux is also weak. We have employed a new sample-mounting technique to obtain neutron powder diffraction patterns from the intermetallic compound Gd(3)Ag(4)Sn(4) containing natural Gd, at a neutron wavelength of ∼ 2.37 Å where there is much greater flux. Here, we report the magnetic structure of Gd(3)Ag(4)Sn(4). The magnetic ordering temperature is 28.8(2) K. At 2.8 K the Gd(4e) sublattice is antiferromagnetically ordered along the crystal c-axis, commensurate with the crystal lattice. The Gd(2d) sublattice is also ordered along the c-axis but its magnetic structure is incommensurate with the crystal lattice.

8.
J Phys Condens Matter ; 21(12): 124210, 2009 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21817452

RESUMO

Intermetallic compounds of the type RFe(10)Si(2) and RCo(10)Si(2) crystallize in the ThMn(12) structure (space group I4/mmm) whilst the heavy rare earth series RNi(10)Si(2) crystallize in a maximal subgroup of I4/mmm, P4/nmm. Reported here are neutron powder diffraction investigations for TbNi(10)Si(2) and ErNi(10)Si(2) which show that the P4/nmm structure undergoes a high temperature order-disorder phase transition at approximately 930 °C above which the ordered Ni and Si fractions revert to a random distribution on 4d and 4e sites. The volume expansion has been tracked in detail via the temperature dependence of the lattice parameters, whilst the temperature dependence of the thermal expansion coefficients α(11), α(33) and α(volume) has been determined from the lattice parameters. Associated with the order-disorder transition is a transition associated with a displacement of the R ion along the c-axis. Both transitions are of second order and the critical exponent associated with the order-disorder and displacive transitions, ß = 0.31, is in excellent agreement with the exponent determined for the three-dimensional Ising model.

9.
Obes Sci Pract ; 4(1): 52-61, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29479465

RESUMO

Objective: Minimal risk weight loss tools are needed. This study's objective was to confirm Food and Drug Administration submissions of the SmartByte™ System's safety and efficacy. Methods: This 16-week, prospective, single-arm, four-centre, observational study assessed the oral device in combination with a video-delivered lifestyle programme in adults aged 18-49 years with body mass index 27 to <35 kg m-2. Results: Seventy-six subjects received the device and video lifestyle instruction. The prespecified per protocol (PP) population (N = 40) required sensor-verified use of the device ≥7 times per week for 14 of 16 weeks, overall device usage rate of ≥33% and study completion. At week 16, 12 (30%) achieved ≥5% weight loss, 16 (40%) achieved ≥4% and 21 (52.5%) achieved ≥3%. Week 16 mean loss for the PP population was 2.93%, and among 36 participants who did not meet PP criteria, it was 1.45%. Among 76 intent-to-treat subjects, two subjects reported three mild to moderate device-related adverse events, resolving spontaneously (one hard palate abrasion and two tongue lacerations). Conclusion: The System, a minimal risk tool, can help individuals achieve meaningful weight loss, when used with a lifestyle video. More frequent device use was associated with more weight loss, on average, and greater chance of achieving ≥4% or ≥5% weight loss.

10.
J Clin Invest ; 88(3): 995-1004, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1715889

RESUMO

Adhesion of B cell precursors to accessory cells in the bone marrow microenvironment may be required for normal early B cell development. Human bone marrow B cell precursors adhere more avidly than mature B cells to bone marrow-derived fibroblasts. To determine the mechanism of this adhesion, expression of adhesion proteins on human B precursor cells and cell lines was measured by flow cytometry. The very late antigen (VLA) integrins VLA-4 and VLA-5 were the only adhesion proteins expressed at higher levels in B cell precursors than mature B cells. Antibodies to the alpha and beta chains of VLA-4, but not VLA-5, significantly blocked binding to bone marrow-derived fibroblasts of immature B cells and cell lines. Although fibronectin is a ligand for VLA-4, anti-fibronectin antibody and a soluble fibronectin fragment containing the VLA-4 binding domain did not block adhesion, suggesting that VLA-4 is involved in adhesion of B cell precursors, but not as a fibronectin receptor. Vascular cell adhesion molecule-1 (VCAM-1), the other known counterreceptor for VLA-4, was identified on bone marrow-derived fibroblasts, and anti-VCAM-1 significantly blocked adhesion of normal B cell precursors to bone marrow-derived fibroblasts, indicating that VLA-4/VCAM-1 interactions are important in adhesion of B cell precursors to the bone marrow microenvironment.


Assuntos
Linfócitos B/fisiologia , Moléculas de Adesão Celular/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Receptores de Antígeno muito Tardio/fisiologia , Adulto , Antígenos CD/análise , Antígenos CD/fisiologia , Células da Medula Óssea , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/análise , Células Cultivadas , Humanos , Antígeno-1 Associado à Função Linfocitária/fisiologia , Receptores de Antígeno muito Tardio/análise , Acetato de Tetradecanoilforbol/farmacologia , Molécula 1 de Adesão de Célula Vascular
11.
J Clin Invest ; 108(7): 1061-70, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11581307

RESUMO

The study of human B cell tolerance has been hampered by difficulties in identifying a sizable population of autoreactive B lymphocytes whose fate could be readily determined. Hypothesizing that B cells expressing intrinsically autoreactive antibodies encoded by the VH4-34 heavy chain gene (VH4-34 cells) represent such a population, we tracked VH4-34 cells in healthy individuals. Here, we show that naive VH4-34 cells are positively selected and mostly restricted to the follicular mantle zone. Subsequently, these cells are largely excluded from the germinal centers and underrepresented in the memory compartment. In healthy donors but not in patients with systemic lupus erythematosus (SLE), these cells are prevented from differentiating into antibody-producing plasma cells. This blockade can be overcome ex vivo using cultures of naive and memory VH4-34 cells in the presence of CD70, IL-2, and IL-10. VH4-34 cells may therefore represent an experimentally useful surrogate for autoantibody transgenes and should prove valuable in studying human B cell tolerance in a physiological, polyclonal environment. Our initial results suggest that both positive and negative selection processes participate in the maintenance of tolerance in autoreactive human B cells at multiple checkpoints throughout B cell differentiation and that at least some censoring mechanisms are faulty in SLE.


Assuntos
Linfócitos B/imunologia , Tolerância Imunológica/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/imunologia , Células da Medula Óssea/imunologia , Diferenciação Celular , Centro Germinativo , Nível de Saúde , Humanos , Memória Imunológica , Lúpus Eritematoso Sistêmico/imunologia , Tonsila Palatina/citologia , Tonsila Palatina/imunologia
12.
Dalton Trans ; 46(45): 15778-15788, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29098218

RESUMO

Polycrystalline samples of Ln2CoGe4O12 (Ln = Gd, Tb, Dy, Ho or Er) and LnBCoGe4O12 (B = Sc or Lu) have been prepared and characterised by a combination of magnetometry, 155Gd Mössbauer spectroscopy and, in the case of Tb2CoGe4O12 and TbScCoGe4O12, neutron diffraction. The holmium- and erbium-containing compositions remain paramagnetic down to 2 K, those containing dysprosium behave as spin glasses and the terbium and gadolinium-containing compounds show long-range magnetic order with transition temperatures below 4 K in all cases. The data can be rationalized qualitatively in terms of the interplay between magnetic anisotropy and crystal field effects.

13.
J Phys Condens Matter ; 29(49): 495804, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29091590

RESUMO

We have determined the magnetic structures of GdCuSn, GdAgSn and GdAuSn using a combination of [Formula: see text]Gd Mössbauer spectroscopy and neutron powder diffraction. Each compound shows the same antiferromagnetic ordering of the Gd sublattice. The magnetic cell is doubled along the crystallographic a-axis (propagation vector [Formula: see text]) with the moments aligned along the hexagonal c-axis, forming alternating ferromagnetic sheets of up/down Gd moments along the a-axis.

14.
Clin Obes ; 7(3): 166-175, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28340516

RESUMO

To assess the association of markers for dietary protein intake, measures of dietary adherence and demographic variables with weight loss in the POUNDS Lost study over the first 6 months and again between 6 and 24 months using data from those who completed each period. This is a secondary analysis of pooled data on completers assigned to one of four diets: 65%C/15%P/20%F (AP/LF), 55%C/25%P/20%F (HP/LF), 45%C/15%P/40%F (AP/HF) or 35%C/25%P40%F (HP/HF) in the POUNDS Lost study. Urinary nitrogen excretion, dietary adherence measured by 24-h recall and attendance at sessions, age (above and below 50 years), gender, race/ethnicity and activity by pedometry were analysed. Increased spread between protein intake at baseline and protein at 6 or 24 months, assessed by urinary nitrogen excretion, was associated with greater weight loss from baseline to 2 years. At 6 and 24 months, older age, male gender, body mass index > 30 kg m-2 and adherence to the fat and protein diets were associated with more weight loss. None of these variables was associated with a regain from 6 to 24 months. Weight regain for women in the highest carbohydrate (65%) group was significantly greater (-4.4 kg [95% CI: -5.9, -3.0]) than for women in the lowest carbohydrate group (-1.8 kg [95% CI: -3.2, -0.4 kg]) (P for interaction = 0.012). An increased spread in the difference between baseline and follow-up protein intake was associated with greater weight loss, consistent with the 'protein spread theory'. Women eating the highest carbohydrate diet regained more weight from 6 to 24 months.


Assuntos
Proteínas Alimentares/metabolismo , Obesidade/dietoterapia , Adulto , Idoso , Biomarcadores/metabolismo , Índice de Massa Corporal , Gorduras na Dieta/análise , Gorduras na Dieta/metabolismo , Proteínas Alimentares/análise , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/psicologia , Cooperação do Paciente , Redução de Peso
15.
Sci Rep ; 7(1): 646, 2017 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-28381825

RESUMO

Neutron powder diffraction patterns measured above T C have been used to determine the location of the excess Mn in MnxGa (1.15 ≤ x ≤ 1.8). This information has then been used to constrain the fits to neutron powder diffraction patterns measured at ambient temperature and so determine unambiguously the Mn moments in this system. We find that Mn randomly occupies the two Ga sites (2a and 2b) in the I4/mmm structure and propose that it is more appropriate to use a simpler structure based on the P4/mmm space group with a reduced unit cell. In this structure the two Ga sites are formally equivalent (they occupy the 1a site while Mn occupies the 1d site). Our experimental observations are supported by DFT calculations. Below T C we find that the Mn(1d) moment is constant at 2.45(3) µ B , while Mn on the 1a site carries a slightly larger moment (~3 µ B ) that is coupled antiparallel to the Mn(1d) moments, leading to the observed drop in magnetisation with increasing Mn content in MnxGa.

16.
Cancer Res ; 46(7): 3420-5, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3708574

RESUMO

To determine incubation conditions that result in optimal in vitro killing of human tumor cells with monoclonal antibody and complement, variables affecting the killing of cultured human neuroblastoma cells with monoclonal antibody 6-19 and baby rabbit complement were studied. Neuroblastoma target cells were stained with the fluorescent dye Hoechst 33342, which enables rapid, sensitive detection of surviving cells in conjunction with trypan blue exclusion. Maximal cell lysis was obtained at an antibody concentration of 5-10 micrograms/ml. Greater than 5 logs of cell kill were obtained with appropriate treatment conditions. No antigenic modulation was detected. Complement activity was found to be the factor which limited the extent of cell kill. Specific cell lysis increased with increasing concentration of complement. As the reaction with antibody coated cells proceeded, complement activity was depleted. This resulted in the greatest cell kill occurring during the first 10-20 min of treatment. Generation of factor(s) inhibitory to complement activity was also found. However, the effect of inhibition on limiting the extent of cell kill was much less significant than the effect of complement depletion. When compared to a single incubation of the same total duration, the reduction in complement activity with duration of incubation resulted in greater killing by multiple brief incubations with fresh complement. The depletion of complement was found to increase at a greater cell concentration. This resulted in greater proportional survival as neuroblastoma cell concentration increased. Depletion of complement activity by aggregated monoclonal antibody was found to decrease cytotoxicity. This evaluation may provide a framework for optimization of target cell destruction using complement and other monoclonal antibodies and target cells.


Assuntos
Anticorpos Monoclonais/imunologia , Ativação do Complemento , Citotoxicidade Imunológica , Neuroblastoma/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Complexo Antígeno-Anticorpo , Antígenos de Neoplasias/imunologia , Relação Dose-Resposta Imunológica , Endocitose , Humanos
17.
J Phys Condens Matter ; 28(26): 266001, 2016 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-27173847

RESUMO

(151)Eu Mössbauer spectroscopy and neutron powder diffraction are combined to show that the tetragonal (I4mm #107) compound EuNiGe3 orders magnetically below [Formula: see text] K and adopts a complex incommensurate helicoidal magnetic structure at 3.6 K, with a propagation vector [Formula: see text] and a Eu moment of 7.1(2) [Formula: see text]. On warming through 6 K an incommensurate sinusoidal modulation develops and dominates the magnetic order by 12 K.

18.
J Phys Condens Matter ; 28(16): 166003, 2016 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-27009349

RESUMO

The antiferromagnetic structures of both the manganese and europium sublattices in EuMn2Ge2 have been determined using thermal neutron diffraction. T(N)(Mn) = 714(5) K with the 3.35(5) µ(B) (at 285 K) Mn moments ordering according to the I4'/m'm'm space group. The Eu order is incommensurate with the 6.1(2) µ(B) (at 3.6 K) Eu moments oriented parallel to the c-axis with a propagation vector of k = [0.153(2) 0 0]. Both neutron diffraction and (151)Eu Mössbauer spectroscopy reveal evidence of magnetic short-range ordering of the Eu sublattice around and above T(N)(Eu) ∼ 10 K. The ordering temperature of the Eu sublattice is strongly affected by the sample's thermal history and rapid quenching from the melting point may lead to a complete suppression of that ordering.

19.
Arch Intern Med ; 159(3): 285-93, 1999 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-9989541

RESUMO

OBJECTIVE: To determine the effects of dietary patterns on blood pressure in subgroups. METHODS: Dietary Approaches to Stop Hypertension (DASH) was a randomized controlled feeding study conducted at 4 academic medical centers. Participants were 459 adults with untreated systolic blood pressure less than 160 mm Hg and diastolic blood pressure 80 to 95 mm Hg. For 3 weeks, participants were fed a "control" diet. They were then randomized to 8 weeks of (1) control diet; (2) a diet rich in fruits and vegetables; or (3) a combination diet rich in fruits, vegetables, and low-fat dairy foods, and reduced in saturated fat, total fat, and cholesterol (the DASH combination diet). Weight and salt intake were held constant. Change in diastolic blood pressure was the primary outcome variable, and systolic blood pressure a secondary outcome. Subgroups analyzed included race, sex, age, body mass index, years of education, income, physical activity, alcohol intake, and hypertension status. RESULTS: The combination diet significantly lowered systolic blood pressure in all subgroups (P<.008), and significantly lowered diastolic blood pressure (P<.01) in all but 2 subgroups. The fruits-and-vegetables diet also reduced blood pressure in the same subgroups, but to a lesser extent. The combination diet lowered systolic blood pressure significantly more in African Americans (6.8 mm Hg) than in whites (3.0 mm Hg), and in hypertensive subjects (11.4 mm Hg) than in nonhypertensive subjects (3.4 mm Hg) (P<.05 for both interactions). CONCLUSIONS: The DASH combination diet, without sodium reduction or weight loss, significantly lowered blood pressure in virtually all subgroups examined, and was particularly effective in African Americans and those with hypertension. The DASH combination diet may be an effective strategy for preventing and treating hypertension in a broad cross section of the population, including segments of the population at highest risk for blood pressure-related cardiovascular disease.


Assuntos
Hipertensão/dietoterapia , Adulto , Negro ou Afro-Americano , População Negra , Feminino , Frutas , Hispânico ou Latino , Humanos , Hipertensão/etnologia , Hipertensão/prevenção & controle , Masculino , Pessoa de Meia-Idade , Verduras , População Branca
20.
Exp Hematol ; 19(1): 63-70, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1703495

RESUMO

Adhesive interactions between CD34+ myeloid progenitors, cytomatrix components, and marrow fibroblast and stromal monolayers are described and compared to the binding interactions of the CD34+ myeloid leukemic cell lines KG1a and KG1. Both normal precursors and their leukemic counterparts showed adhesion to marrow stroma and fibroblasts. CD34+ myeloid progenitors bound to the extracellular matrices of marrow stromal cell and fibroblast monolayers and to laminin and fibronectin to a lesser extent than to cellular stromal layers. These adhesive interactions were not inhibited by polyclonal antibodies to laminin or fibronectin, nor by 1 mM Arg-Gly-Asp-Ser (RGDS)-containing peptides. Also, although both normal and leukemic cells expressed the CD18 antigen, binding of these cells to stroma was not inhibited by blocking anti-CD18 monoclonal antibodies. Finally, KG1a adhesion was not blocked in the presence of anti-CD54 (ICAM) antibody, nor was it blocked when galactosyl or mannosyl pyranosides were added. KG1a binding was trypsin sensitive and enhanced in the presence of neuraminidase. These studies serve to characterize adhesive properties of normal and leukemic myeloid progenitors and begin to establish interactions important for the lodgement of early progenitor cells in human marrow.


Assuntos
Antígenos de Diferenciação/análise , Medula Óssea/patologia , Leucemia/patologia , Células-Tronco/fisiologia , Antígenos CD/análise , Antígenos CD34 , Medula Óssea/fisiologia , Adesão Celular , Linhagem Celular , Ensaio de Unidades Formadoras de Colônias , Fibroblastos/fisiologia , Humanos , Valores de Referência , Células-Tronco/imunologia
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