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1.
Trends Ecol Evol ; 39(4): 349-358, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38087707

RESUMO

Fine-grained environmental data across large extents are needed to resolve the processes that impact species communities from local to global scales. Ground-based images (GBIs) have the potential to capture habitat complexity at biologically relevant spatial and temporal resolutions. Moving beyond existing applications of GBIs for species identification and monitoring ecological change from repeat photography, we describe promising approaches to habitat mapping, leveraging multimodal data and computer vision. We illustrate empirically how GBIs can be applied to predict distributions of species at fine scales along Street View routes, or to automatically classify and quantify habitat features. Further, we outline future research avenues using GBIs that can bring a leap forward in analyses for ecology and conservation with this underused resource.


Assuntos
Biodiversidade , Ecossistema
2.
Angle Orthod ; 93(6): 683-694, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37922389

RESUMO

OBJECTIVE: To evaluate the mandibular alveolar bone thickness in untreated skeletal Class I subjects with different vertical skeletal patterns. MATERIALS AND METHODS: A total of 50 preorthodontic treatment cone-beam computed tomography (CBCT) images of a skeletal Class I Chinese population with near-normal occlusion were selected. The buccal and lingual alveolar bone thicknesses of mandibular canines to second molars were measured at 2 mm below the cementoenamel junction (CEJ), mid-root, and root apex levels. Differences in the measurements were analyzed with Mann-Whitney U-test. The correlation between alveolar bone thickness and the sella-nasion-mandibular plane (SN-MP) angle was calculated using Pearson correlation coefficients and linear regression analysis. RESULTS: Buccal alveolar bone was thinner on all mandibular canines to first molars but thicker on second molars in comparison with lingual alveolar bone. Buccal alveolar bone was within 1 mm at the levels of 2 mm below CEJ and mid-root for the canines and first premolars. Significant differences were detected among subjects with different vertical patterns, with a negative correlation between the SN-MP angle and alveolar thickness, especially in the canine and premolar regions. The thinnest buccal and lingual alveolar bone were detected in the high-angle group canine region (0.50 mm at the levels of 2 mm below CEJ and mid-root for the buccal side, 0.90 mm at the level of 2 mm below the CEJ for the lingual side). CONCLUSIONS: To avoid periodontal complications, buccal-lingual movement of the mandibular canines and first premolars should be limited, especially in high-angle patients.


Assuntos
Dente Canino , Mandíbula , Humanos , Mandíbula/diagnóstico por imagem , Dente Pré-Molar/diagnóstico por imagem , Dente Canino/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos
3.
Clin Oral Investig ; 27(5): 2097-2107, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37022530

RESUMO

OBJECTIVES: Currently available reports on mandibular transverse growth are limited to two-dimensional images and cross-sectional studies. The objective of this study was to examine transverse growth of the mandibular body in untreated growing individuals during the mixed dentition stage using longitudinal three-dimensional imaging. METHODS: CBCT images of 25 (13 females and 12 males) untreated subjects at two time points were analyzed. The average age was 9.1 years at T1 and 11.3 years at T2. Mandibular segmentation and superimposition were performed to obtain linear and angular measurements at different axial levels. RESULTS: At the superior (mental foramen) axial level, transverse growth between the buccal surfaces gradually increased from the premolars to the ramus. At the inferior axial level, significant transverse growth differences were detected between the ramus and the dentition regions. In contrast, between the lingual surfaces, both superior and inferior levels showed minimal change in the region under the dentition and a significant amount of resorption in the ramus region. This difference between buccal and lingual surface changes led to a mandibular body angulation change in the premolar and molar regions. In contrast, the overall mandibular body angulation measured from the posterior-most border of the mandible to the symphysis remained the same. Differences were detected between males and females, with males tending to exhibit greater transverse growth in the ramus region at the inferior level. CONCLUSIONS: The mandibular body exhibited different transverse growth patterns at different axial levels. Differences were also found between genders. CLINICAL RELEVANCE: An in-depth understanding of craniofacial growth and development is crucial to diagnosis and treatment planning. The current study provides additional insight into the transverse growth of the mandible.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Masculino , Feminino , Criança , Estudos Transversais , Dente Molar , Dente Pré-Molar/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico
4.
Am J Orthod Dentofacial Orthop ; 163(3): 407-425, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36517377

RESUMO

INTRODUCTION: Currently, there is little consensus regarding the spontaneous uprighting of the mandibular dentoalveolar complex in response to maxillary expansion, which poses the question about the necessity of combining mandibular treatment with rapid maxillary expansion to coordinate the maxilla and mandible transversely. This study aimed to evaluate the effects of the bonded rapid maxillary expander (RME) alone compared with RME with lip bumper (LB) treatment on the mandibular transverse changes. METHODS: This retrospective study analyzed 3 groups: the control group with no orthodontic or orthopedic treatment (23 patients [14 females, 9 males]; mean age 9.13 years at T1 and 11.24 years at T2); the RME group with no mandibular treatment (22 patients [9 females, 13 males]; mean age 8.73 years at T1 and 12.04 years at T2); and RME + LB group (23 patients [16 females, 7 males]; mean age 9.45 years at T1 and 12.18 years at T2). Three-dimensional superimposition of the mandibular images was performed with cone-beam computed tomography taken at prephase and postphase I treatment (growth and development check records for the control group) to conduct the angular and linear measurements at the dental, alveolar, and skeletal levels. The intergroup comparisons were performed using the Mann-Whitney U-test. RESULTS: Accompanying slight molar self-uprighting during the normal mandibular growth period observed in the control group, transverse growth was also observed in both alveolar and basal bone levels of the mandible, but no significant changes in the alveolar bone inclination occurred. The bonded RME slightly increased the mandibular first molar uprighting but not the mandibular widths at the tooth or alveolar levels. Adding a LB significantly increased the intermolar width and molar uprighting while decreasing the alveolar bone inclination but did not increase the amount of mandibular transverse growth at the bone level. CONCLUSIONS: RME alone did not significantly increase the transverse dimension of the mandible. RME + LB significantly increased mandibular intermolar width, uprighted the mandibular molars, and reduced the alveolar bone inclination.


Assuntos
Lábio , Maxila , Masculino , Feminino , Humanos , Criança , Estudos Retrospectivos , Tomografia Computadorizada de Feixe Cônico/métodos , Técnica de Expansão Palatina , Mandíbula
5.
Diagnostics (Basel) ; 14(1)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38201353

RESUMO

This study aims to determine if a large anterior and reduced posterior/superior joint space is highly predictable for disc displacement. From patients with temporomandibular disorders symptoms, fifty-two experimental joints and fourteen control joints were included. The cone beam computed tomography (CBCT) images were used to calculate posterior-to-anterior (P-A) and superior-to-anterior (S-A) joint space ratios, while disc position was determined using magnetic resonance imaging (MRI). One-way analysis of covariance test and receiver operating characteristics analysis were carried out. The results showed that among the 52 experimental joints, 45 were diagnosed as disc displacement and 7 as normal disc positions (N). All 14 control joints showed normal disc positions. The P-A ratio was 1.46 ± 0.21, 0.99 ± 0.23, and 0.86 ± 0.30 in the control, N, and DD groups, respectively (p < 0.001). The S-A ratio was 1.80 ± 0.27, 1.44 ± 0.33, and 1.08 ± 0.35 in the control, N, and DD groups, respectively (p < 0.001). When an altered P-A ratio and/or S-A ratio are observed on the CBCT, the diagnosis of disc displacement is quite predictable with high sensitivity and specificity.

6.
J Clin Med ; 11(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36431105

RESUMO

The mandibular second molars are lingually positioned relative to the alveolar ridge and have a limited amount of lingual alveolar bony support. As the maxillary second molars are articulated with the mandibular second molars, maintaining the normal buccolingual inclination of both maxillary and mandibular second molars would potentially help to not only optimize the masticatory function, but also avoid dehiscence and fenestration. The current study evaluated the buccolingual inclination of second molars in untreated adolescents and adults. One hundred and two Caucasian subjects with skeletal class I and minimum dental arch crowding/spacing were selected and divided into two groups: (1) adolescent group: age 12-18 years, N = 51 (21 females, 30 males); (2) adult group: age 19-65 years, N = 51 (40 females, 11 males). For each subject, the inclination for each second molar was measured as the angle between the long axis of each tooth and a vertical line on cone beam computed tomography images. The Mann-Whitney U test was used for intergroup comparisons. Maxillary second molars exhibited a buccal inclination of 15.30° in the adolescent group and 15.70° in the adult group. Mandibular second molars exhibited a lingual inclination of 17.05° in the adolescent group and 15.20° in the adult group. No statistically significant differences were detected between the age groups. In addition, a statistically significant difference was only found between genders in the adolescent group for the maxillary second molar inclination. In summary, maxillary second molars exhibited buccal inclination and mandibular second molars exhibited lingual inclination. The amount of buccolingual inclination of the second molars was similar in the adolescent and adult groups.

7.
J Clin Med ; 11(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36294352

RESUMO

Lip bumper (LB) therapy is used as a treatment approach for mild to moderate crowding without extraction of teeth. Previous studies demonstrated that LB increases arch length through molar uprighting and lateral expansion. However, the effects of LB on mandibular incisors are inconclusive. The controversial results from different studies may be due to limitations including absence of a control group and/or use of 2D radiography. To address this issue, the current retrospective longitudinal CBCT study compared a rapid maxillary expansion (RME) group with no lower treatment [16 patients (9 females, 7 males); median age 8.86 years at T1 and 11.82 years at T2] and an RME + LB group [18 patients (13 females, 5 males); median age 9.46 years at T1 and 12.10 years at T2]. The CBCTs taken before and after phase 1 treatment were 3D superimposed based on the mandibular structure and were measured to determine the angular and linear changes of the mandibular incisors over the course of LB treatment. For comparisons between different timepoints within a group, a Wilcoxon matched-pairs signed rank test was used. For intergroup comparisons, a Mann-Whitney U test was used. Both groups showed eruption and protrusion of the mandibular incisors during the observation period, while there was no significant change in proclination of the lower incisors. When comparing the discrepancy of change between groups, there was no statistically significant difference detected. In summary, by utilizing a longitudinal 3D database, the current study demonstrated that the effect of LB on the position of the mandibular incisors is limited.

8.
Angle Orthod ; 91(1): 46-53, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33289784

RESUMO

OBJECTIVES: To evaluate nasal soft and hard tissue changes immediately post-rapid maxillary expansion (RME) and to assess the stability of these changes using cone beam computed tomography (CBCT). MATERIALS AND METHODS: A total of 35 treatment group (TG) patients (18 girls, 17 boys; 9.39 ± 1.4) had a pre-RME CBCT and a post-RME CBCT approximately 66 days after expansion, and 25 patients had a follow-up CBCT 2.84 years later. A total of 28 control group (CG; no RME) patients (16 girls, 12 boys; 8.81 ± 1.6) had an initial CBCT and a CBCT an average of 2.25 years later. Soft and hard tissue nasal landmarks were measured in transverse, sagittal, and coronal planes of space on CBCT scans. Differences within the same group were evaluated by paired t-tests or Wilcoxon signed-rank tests. Long-term comparisons between TG and CG were evaluated by independent-sample t-tests or Wilcoxon rank-sum tests. RESULTS: Immediately post-RME, there were statistically significant mean increases of 1.6 mm of alar base width, 1.77 mm of pyriform height, and 3.57 mm of pyriform width (P < .05). CG showed the significant increases over 2.25 years (P < .001). Compared with CG, the long-term evaluation of TG demonstrated only pyriform height and pyriform width showed a statistically significant difference (P < .01). CONCLUSIONS: Although RME produced some significant increase on the nasal soft tissue immediately after expansion, it regressed to the mean of normal growth and development over time. However, long-term evaluation of TG compared with CG showed only pyriform height and pyriform width to be affected by RME.


Assuntos
Técnica de Expansão Palatina , Dente , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Maxila , Nariz/diagnóstico por imagem
9.
Nat Commun ; 11(1): 1351, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32165619

RESUMO

The majority of variation in six traits critical to the growth, survival and reproduction of plant species is thought to be organised along just two dimensions, corresponding to strategies of plant size and resource acquisition. However, it is unknown whether global plant trait relationships extend to climatic extremes, and if these interspecific relationships are confounded by trait variation within species. We test whether trait relationships extend to the cold extremes of life on Earth using the largest database of tundra plant traits yet compiled. We show that tundra plants demonstrate remarkably similar resource economic traits, but not size traits, compared to global distributions, and exhibit the same two dimensions of trait variation. Three quarters of trait variation occurs among species, mirroring global estimates of interspecific trait variation. Plant trait relationships are thus generalizable to the edge of global trait-space, informing prediction of plant community change in a warming world.


Assuntos
Desenvolvimento Vegetal , Tundra , Clima , Ecossistema , Plantas/classificação , Plantas/genética
10.
Glob Ecol Biogeogr ; 28(2): 78-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31007605

RESUMO

AIM: Plant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits. LOCATION: Tundra biome. TIME PERIOD: Data collected between 1964 and 2016. MAJOR TAXA STUDIED: 295 tundra vascular plant species. METHODS: We compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species-level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and species composition of functional groups to alternative classifications generated using post hoc clustering of species-level traits. RESULTS: Traditional functional groups explained significant differences in trait expression, particularly amongst traits associated with resource economics, which were consistent across sites and at the biome scale. However, functional groups explained 19% of overall trait variation and poorly represented differences in traits associated with plant size. Post hoc classification of species did not correspond well with traditional functional groups, and explained twice as much variation in species-level trait expression. MAIN CONCLUSIONS: Traditional functional groups only coarsely represent variation in well-measured traits within tundra plant communities, and better explain resource economic traits than size-related traits. We recommend caution when using functional group approaches to predict tundra vegetation change, or ecosystem functions relating to plant size, such as albedo or carbon storage. We argue that alternative classifications or direct use of specific plant traits could provide new insights for ecological prediction and modelling.

11.
Mucosal Immunol ; 11(3): 811-819, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29139477

RESUMO

Flavones represent a class of polyphenols that are found in many plant-derived food sources. Herein, we provide evidence that the anti-inflammatory and antiproliferative effect of the flavone apigenin relies on the regulation of the gut microbiota by the NOD-like receptor family pyrin domain containing 6 (Nlrp6). When challenged by dextran sulfate sodium (DSS) in drinking water, mice were protected against colitis upon cohousing with apigenin-treated animals. In contrast, the protective effect was lost in the absence of Nlrp6. Sequencing of the 16S ribosomal RNA gene revealed a shift in the composition of the gut microbiota in apigenin-treated mice that was not observed in the absence of Nlrp6. Equally important, we find that the antiproliferative effect of apigenin was dominantly transmitted after cohousing, while being compromised in Nlrp6-deficient mice. In contrast, the symptoms of colitis were alleviated upon apigenin administration even in the absence of either caspase-1/11 or Asc. Collectively, these data indicate that apigenin modulated an inflammasome-independent mechanism by which Nlrp6 reprograms the gut microbiota for protecting mice against colitis. Our study highlights a modulation of the Nlrp6 signaling pathway by a prominent constituent of the human diet that may point toward improved ways to treat inflammatory bowel diseases.


Assuntos
Apigenina/administração & dosagem , Colite/prevenção & controle , Dieta , Flavonas/administração & dosagem , Microbioma Gastrointestinal/fisiologia , Doenças Inflamatórias Intestinais/dietoterapia , Receptores de Superfície Celular/metabolismo , Animais , Colite/induzido quimicamente , Sulfato de Dextrana , Abrigo para Animais , Humanos , Inflamassomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Ribossômico 16S/genética , Receptores de Superfície Celular/genética , Transdução de Sinais
12.
Eur J Clin Nutr ; 69(6): 740-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25852025

RESUMO

BACKGROUND/OBJECTIVES: Foods with high contents of slowly digestible starch (SDS) elicit lower glycemic responses than foods with low contents of SDS but there has been debate on the underlying changes in plasma glucose kinetics, that is, respective contributions of the increase in the rates of appearance and disappearance of plasma glucose (RaT and RdT), and of the increase in the rate of appearance of exogenous glucose (RaE) and decrease in endogenous glucose production (EGP). SUBJECTS/METHODS: Sixteen young healthy females ingested in random order four types of breakfasts: an extruded cereal (0.3% SDS: Lo-SDS breakfast) or one of three biscuits (39-45% SDS: Hi-SDS breakfasts). The flour in the cereal products was labeled with (13)C, and plasma glucose kinetics were measured using [6,6-(2)H2]glucose infusion, along with the response of plasma glucose, insulin and glucose-dependent insulinotropic peptide (GIP) concentrations. RESULTS: When compared with the Lo-SDS breakfast, after the three Hi-SDS breakfasts, excursions in plasma glucose, the response of RaE, RaT and RdT, and the reduction in EGP were significantly lower (P<0.05). The amount of exogenous glucose absorbed over the 4.5-h postprandial period was also significantly lower by ~31% (P<0.001). These differences were associated with lower responses of GIP and insulin concentrations. CONCLUSIONS: Substituting extruded cereals with biscuits slows down the availability of glucose from the breakfast and its appearance in peripheral circulation, blunts the changes in plasma glucose kinetics and homeostasis, reduces excursions in plasma glucose, and possibly distributes the glucose ingested over a longer period following the meal.


Assuntos
Glicemia/análise , Desjejum , Digestão , Grão Comestível , Polipeptídeo Inibidor Gástrico/sangue , Insulina/sangue , Amido/metabolismo , Adolescente , Adulto , Pão , Estudos Cross-Over , Carboidratos da Dieta/metabolismo , Feminino , Índice Glicêmico , Humanos , Insulina/metabolismo , Resistência à Insulina , Secreção de Insulina , Absorção Intestinal , Período Pós-Prandial , Quebeque , Adulto Jovem
13.
Horm Metab Res ; 46(6): 390-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24806747

RESUMO

Our aim was to characterize the effects and the underlying mechanisms of the lipid-regulating agent Niaspan(®) on both insulin action and triglyceride decrease in 20 nondiabetic, dyslipidemic men with metabolic syndrome receiving Niaspan(®) (2 g/day) or placebo for 8 weeks in a randomized, cross-over study. The effects on plasma lipid profile were characterized at the beginning and the end of each treatment period; insulin sensitivity was assessed using the 2-step euglycemic hyperinsulinemic clamp and VLDL-triglyceride turnover by measuring plasma glycerol enrichment, both at the end of each treatment period. The mechanism of action of nicotinic acid was studied in HuH7 and mouse primary hepatocytes. Lipid profile was improved after Niaspan(®) treatment with a significant-28% decrease in triglyceride levels, a+17% increase in HDL-C concentration and unchanged levels of fasting nonesterified fatty acid. VLDL-tri-glyceride production rate was markedly reduced after Niaspan(®) (-68%). However, the treatment induced hepatic insulin resistance, as assessed by reduced inhibition of endogenous glucose production by insulin (0.7±0.4 vs. 1.0±0.5 mg/kg · min, p<0.05) and decrease in fasting hepatic insulin sensitivity index (4.8±1.8 vs. 3.2±1.6, p<0.05) in the Niaspan(®) condition. Nicotinic acid also reduced insulin action in HuH7 and primary hepatocytes, independently of the activation of hepatic PKCε. This effect was associated with an increase in diacylglycerol and a decrease in tri-glyceride contents that occurred in the absence of modification of DGAT2 expression and activity. Eight weeks of Niaspan(®) treatment in dyslipidemic patients with metabolic syndrome induce hepatic insulin resistance. The mechanism could involve an accumulation of diacylglycerol and an alteration of insulin signaling in hepatocytes.


Assuntos
Insulina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Niacina/farmacologia , Animais , Linhagem Celular Tumoral , Diglicerídeos/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Cinética , Lipoproteínas VLDL/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Niacina/administração & dosagem , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Triglicerídeos/metabolismo
14.
Obes Rev ; 13(10): 923-84, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22780564

RESUMO

Postprandial glucose, together with related hyperinsulinemia and lipidaemia, has been implicated in the development of chronic metabolic diseases like obesity, type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). In this review, available evidence is discussed on postprandial glucose in relation to body weight control, the development of oxidative stress, T2DM, and CVD and in maintaining optimal exercise and cognitive performance. There is mechanistic evidence linking postprandial glycaemia or glycaemic variability to the development of these conditions or in the impairment in cognitive and exercise performance. Nevertheless, postprandial glycaemia is interrelated with many other (risk) factors as well as to fasting glucose. In many studies, meal-related glycaemic response is not sufficiently characterized, or the methodology with respect to the description of food or meal composition, or the duration of the measurement of postprandial glycaemia is limited. It is evident that more randomized controlled dietary intervention trials using effective low vs. high glucose response diets are necessary in order to draw more definite conclusions on the role of postprandial glycaemia in relation to health and disease. Also of importance is the evaluation of the potential role of the time course of postprandial glycaemia.


Assuntos
Peso Corporal/fisiologia , Doença Crônica/epidemiologia , Hiperglicemia/fisiopatologia , Obesidade/metabolismo , Glicemia/metabolismo , Doença Crônica/prevenção & controle , Humanos , Hiperglicemia/metabolismo , Incretinas/metabolismo , Período Pós-Prandial , Fatores de Risco
15.
Stat Med ; 30(16): 1971-88, 2011 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21520217

RESUMO

Estimation of the effect of one treatment compared to another in the absence of randomization is a common problem in biostatistics. An increasingly popular approach involves instrumental variables-variables that are predictive of who received a treatment yet not directly predictive of the outcome. When treatment is binary, many estimators have been proposed: method-of-moments estimators using a two-stage least-squares procedure, generalized-method-of-moments estimators using two-stage predictor substitution or two-stage residual inclusion procedures, and likelihood-based latent variable approaches. The critical assumptions to the consistency of two-stage procedures and of the likelihood-based procedures differ. Because neither set of assumptions can be completely tested from the observed data alone, comparing the results from the different approaches is an important sensitivity analysis. We provide a general statistical framework for estimation of the casual effect of a binary treatment on a continuous outcome using simultaneous equations to specify models. A comparison of health care costs for adults with schizophrenia treated with newer atypical antipsychotics and those treated with conventional antipsychotic medications illustrates our methods. Surprisingly large differences in the results among the methods are investigated using a simulation study. Several new findings concerning the performance in terms of precision and robustness of each approach in different situations are obtained. We illustrate that in general supplemental information is needed to determine which analysis, if any, is trustworthy and reaffirm that comparing results from different approaches is a valuable sensitivity analysis.


Assuntos
Antipsicóticos/economia , Antipsicóticos/uso terapêutico , Bioestatística/métodos , Custos de Medicamentos/estatística & dados numéricos , Esquizofrenia/tratamento farmacológico , Esquizofrenia/economia , Adulto , Teorema de Bayes , Feminino , Humanos , Análise dos Mínimos Quadrados , Funções Verossimilhança , Masculino , Modelos Estatísticos , Análise de Regressão , Resultado do Tratamento
16.
Rev Sci Instrum ; 81(10): 10E509, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21034037

RESUMO

This imaging system aims at recording images of the core size and shape of an imploding deuterium-tritium (DT) microballoon on LMJ inertial confinement fusion (ICF) experiments. Image acquisition is difficult due to the harsh surrounding created by the fusion reaction, which affects system specifications. This one is made of a scintillator, an optical relay, and a CCD camera shielded from the surrounding. The system was tested on different facilities at CEA/DIF, where a spatial resolution of 120 µm was achieved and gamma dose up to 20 rad effects were measured. Setup and performed test are described.

17.
J Nutr Health Aging ; 14(7): 579-84, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20818474

RESUMO

BACKGROUND: Among various nutrients branched amino acids (BCAAS) have been shown to be the most responsible for the stimulation of protein synthesis in various situations including catabolic states. OBJECTIVES: We evaluated the effect of a small amount of proteins enriched with BCAAs (0.4 g/kg/day and 0.2 g/kg/day BCAAs) on body weight and composition; nitrogen balance, energy intake and inflammation after 2 weeks of supplementation in acute elderly with catabolic status. DESIGN: Two weeks randomized controlled trial. SETTING: Geriatric department of teaching hospital. SUBJECTS: Thirty patients with malnutrition and inflammatory process (MNA < 24, albumin < 30 g/l and CRP > or = 20 mg/l) who agreed to participate in the study were consecutively included. METHODS: Body composition was determined by labelled water dilution method; resting energy expenditure (REE) was determined by indirect calorimetry; energy intake was calculated for a 3 days period at D1 and D12. Nutritional and inflammatory proteins and cytokines (IL-6 and TNF) were measured at day 1 and 14. RESULTS: No difference was observed at day 14 between supplemented (S) and control (C) group for weight (S: 58.0 +/- 11.8 kg and C: 60.0 +/- 15.9 kg); fat free mass (S: 40.7 +/- 8.3 kg and C: 40 +/- 8.2 kg); nitrogen balance (S: 1.34 +/- 2.21 g/day and C: 0.59 +/- 4.47 g/day); and energy intake (S: 20 +/- 3.6 kcal/day and C: 20.5 +/- 8.6 kcal/day). Energy intake was at similar level than REE and clearly less than energy requirement in C and S. A significant decrease was observed for orosomucoid and Prognostic Inflammatory and Nutritional Index (PINI) in S. CONCLUSION: Our results do not confirm improvement of nutritional status with enriched BCAAs supplementation as suggested in the literature. Persistence of inflammatory condition may be an explanation despite an improvement of inflammatory status was observed in the supplemented group. Those results show clearly that energy requirements are not covered in acute hospitalized elderly people. The fact that not only energy intake but also REE are decreased brings a new insight on catabolic situations.


Assuntos
Aminoácidos/uso terapêutico , Suplementos Nutricionais , Inflamação/tratamento farmacológico , Desnutrição/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Aminoácidos/farmacologia , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Feminino , Humanos , Inflamação/complicações , Masculino , Desnutrição/complicações , Nitrogênio/sangue , Estado Nutricional/efeitos dos fármacos , Orosomucoide/metabolismo
18.
J Chromatogr A ; 1164(1-2): 240-7, 2007 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-17628580

RESUMO

Two methods for the sampling and analysis of tar produced from wood pyrolysis were compared. The first method used a conventional cold-trapping technique in solvent-filled impingers followed by liquid injection. The second one is a new application of multibed solid-phase adsorbent (SPA) tubes followed by thermal desorption (TD). Both methods are based on gas chromatography (GC) coupled with mass spectrometry (MS). Quantification was performed with a well reproducible GC-MS method with three internal deuterated standards. The SPA/TD method offers several advantages. No solvent is required, the detection levels are improved, and gas chromatography separation is easier. Moreover, sampling time is reduced from about 1h (for the conventional cold-trapping technique in impingers) to a few seconds. No discrimination was observed between the two sampling methods for the 10 quantified compounds (aromatic compounds from benzene to phenanthrene and phenols) except for benzene.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Alcatrões/química , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Aromáticos/química , Reprodutibilidade dos Testes
19.
Br J Nutr ; 89(5): 731-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12720593

RESUMO

Fighting against inactivity and inadequate nutritional intake are of utmost importance in the elderly. To our knowledge, the few studies which have been performed were conducted for only a short period and the results do not permit formal conclusions to be drawn. We therefore tried to fill this gap in our knowledge by determining whether an intervention combining an acceptable progressive exercise programme and nutritional supplements would be feasible for a long-term period in the very frail elderly, and would bring about concomitant benefits in body composition and muscle power. Accordingly, this exercise and nutritional combination was assessed in the frail elderly in a 9-month randomised trial with a factorial design. Fifty-seven elderly volunteers over 72 years, from sixteen retirement homes in Lyon, France participated in the study. Dietary supplements were compared with placebo, and physical exercise was compared with memory training. Main outcome measures were fat-free mass (FFM) and muscle power. FFM was determined by labelled water, and muscle power was measured by a leg-extensor machine. At 9 months, the compliance was 63 % for exercise sessions, and 54 % for nutritional supplements. In patients with dietary supplements, muscle power increased by 57 % at 3 months (P=0.03), and showed only a tendency at 9 months; although FFM increased by 2.7 % at 9 months, the difference was not significant (P=0.10). Exercise did not improve muscle power at 9 months, but improved functional tests (five-time-chair rise, P=0.01). BMI increased with supplements (+3.65 %), but decreased with placebo (-0.5 %) at 9 months (P=0.007). A long-term combined intervention is feasible in frail elderly individuals with a good rate of compliance. Nutritional supplements and exercise may improve muscle function. Despite no significant results on FFM, due to the limited number of volunteers, combined intervention should be suggested to counteract muscle weakness in the frail elderly.


Assuntos
Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Terapia por Exercício , Idoso Fragilizado , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Composição Corporal , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Metabolismo Energético , Seguimentos , Humanos , Músculos/fisiologia , Fatores de Tempo
20.
Psychol Med ; 32(6): 959-76, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12214795

RESUMO

BACKGROUND: A 10-question screening scale of psychological distress and a six-question short-form scale embedded within the 10-question scale were developed for the redesigned US National Health Interview Survey (NHIS). METHODS: Initial pilot questions were administered in a US national mail survey (N = 1401). A reduced set of questions was subsequently administered in a US national telephone survey (N = 1574). The 10-question and six-question scales, which we refer to as the K10 and K6, were constructed from the reduced set of questions based on Item Response Theory models. The scales were subsequently validated in a two-stage clinical reappraisal survey (N = 1000 telephone screening interviews in the first stage followed by N = 153 face-to-face clinical interviews in the second stage that oversampled first-stage respondents who screened positive for emotional problems) in a local convenience sample. The second-stage sample was administered the screening scales along with the Structured Clinical Interview for DSM-IV (SCID). The K6 was subsequently included in the 1997 (N = 36116) and 1998 (N = 32440) US National Health Interview Survey, while the K10 was included in the 1997 (N = 10641) Australian National Survey of Mental Health and Well-Being. RESULTS: Both the K10 and K6 have good precision in the 90th-99th percentile range of the population distribution (standard errors of standardized scores in the range 0.20-0.25) as well as consistent psychometric properties across major sociodemographic subsamples. The scales strongly discriminate between community cases and non-cases of DSM-IV/SCID disorders, with areas under the Receiver Operating Characteristic (ROC) curve of 0.87-0.88 for disorders having Global Assessment of Functioning (GAF) scores of 0-70 and 0.95-0.96 for disorders having GAF scores of 0-50. CONCLUSIONS: The brevity, strong psychometric properties, and ability to discriminate DSM-IV cases from non-cases make the K10 and K6 attractive for use in general-purpose health surveys. The scales are already being used in annual government health surveys in the US and Canada as well as in the WHO World Mental Health Surveys. Routine inclusion of either the K10 or K6 in clinical studies would create an important, and heretofore missing, crosswalk between community and clinical epidemiology.


Assuntos
Estresse Psicológico/diagnóstico , Estresse Psicológico/epidemiologia , Inquéritos e Questionários/normas , Adulto , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Projetos Piloto , Prevalência , Psicometria , Curva ROC , Reprodutibilidade dos Testes , Estados Unidos/epidemiologia
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