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1.
J Med Educ Curric Dev ; 11: 23821205241246889, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617120

RESUMO

OBJECTIVES: High-need, high-cost (HNHC) patients represent a small proportion of patients in the US, but result in disproportionately higher healthcare utilization. Teaching Internal Medicine (IM) resident trainees to provide high value care for HNHC patients is critical. We sought to improve resident attitudes and increase clinical skills associated with treating HNHC patients by creating a curriculum that leveraged the UCLA Extensivist Program, a patient-centered medical home for HNHC patients. METHODS: We developed a curriculum for PGY-2 and PGY-3 IM residents centered on caring for HNHC patients over the course of 6, 4h sessions during 1 academic year. Participants completed pre- and post-intervention surveys assessing self-rated attitudes and skills associated with caring for an HNHC patient population. RESULTS: Twenty-one IM residents completed the curriculum and 41 were in the control group. There were no statistically significant differences in assessed attitudes and skills, but there were trends of improvement, including a decrease in participants who agreed or strongly agreed they felt overwhelmed when seeing patients for posthospital discharge follow up (45.0% pre- to 41.7% post-intervention) and an increase in participants who agreed or strongly agreed they have the skills to successfully transition HNHC patients between inpatient and ambulatory settings (20.0% pre- to 33.3% post-intervention). Participants reported better understanding of resources available to HNHC patients, effective coordination of transitions of care, and comprehensive assessment of social determinants of health. CONCLUSION: A curriculum to improve resident attitudes and skills associated with caring for HNHC patients was successfully implemented in an IM program at a large academic medical center. The curriculum may be adapted for other training programs; long-term training woven throughout training may be important to significantly improve resident education on how to care for HNHC patients.

2.
Ann Diagn Pathol ; 69: 152266, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38266545

RESUMO

Intraoperative consultation of donor liver is an important part of transplant evaluation and determination of liver eligibility. In this study, we describe incidental pathologic findings discovered during the pretransplant evaluation of liver donors in our Institution from 1/2010 to 12/2022. During this 13-year period 369 intraoperative consultations from 262 liver donors were performed. Of those cases, incidental findings were identified in 22 cases (5.9 %) from 19 donors (7.3 %); two donors had more than one lesion. The median age of this subset of patients was 53 years (range: 18-70) and females predominated (63 %). Sixteen of the donors had abnormal findings in the liver: 6 bile duct hamartoma (BDH), 5 hyalinized nodule with Histoplasma capsulatum, 5 focal nodular hyperplasia (FNH), 2 bile duct adenomas (BDA), 1 biliary cyst and 1 hemangioma. One donor had both FNH and a BDH. One BDH and 1 BDA case was misdiagnosed as malignancy during the frozen section evaluation. Three donors had extrahepatic pathologies: a pancreatic tail schwannoma, a low-grade appendiceal mucinous neoplasm, and a lymph node with metastatic endometrial endometrioid adenocarcinoma. Of the 19 livers, the final organ disposition was available for 9: 6 were transplanted (67 %) and 3 were discarded (33 %). Two of the 3 discarded organs were misdiagnosed BDH and BDA cases, and one was incorrectly reported as having 90 % microvesicular steatosis during the frozen assessment. We present the clinicopathologic characteristics of liver donors with incidental findings during the pre-transplant evaluation which could lead to unwarranted graft dismissal if misdiagnosed. Additionally, incidental fungal infections can have implications for immunosuppressive therapy and the decision to use or reject the graft.


Assuntos
Fígado Gorduroso , Transplante de Fígado , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Achados Incidentais , Doadores Vivos , Fígado/patologia , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/patologia
3.
Nan Fang Yi Ke Da Xue Xue Bao ; 42(3): 384-391, 2022 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-35426802

RESUMO

OBJECTIVE: To screen the effective antioxidant components in Trichosanthes extract based on the mean value of Deng's correlation degree and assess the antioxidant activity of the identified components. METHOD: High-performance liquid chromatography (HPLC) was used to obtain the fingerprints of Trichosanthes extract, and the clearance rates of DPPH · and O2-· by 3, 9 and 27 mg/mL Trichosanthes extract were determined. The antioxidant spectrum effect of Trichosanthes extract was analyzed by calculating the mean value of Deng's correlation degree to screen the effective antioxidant component group. According to the contents of each known components in the antioxidant effective component group, mixed solutions of the components were prepared and tested for their clearance rates of DPPH · and O2-·. RESULTS: The 36 common peaks in HPLC fingerprints of Trichosanthes extract showed different degrees of correlation with DPPH · and O2-· clearance. The common peaks with a correlation degree greater than the median value included peaks 21, 36, 8, 31, 14, 5, 27, 2, 24, 15, 18, 33, 22, 34, 35, 19, 28 and 25. The 5 components, namely kaempferol (peak 36), isoquercitrin (peak 8), luteolin (peak 31), rutin (peak 5) and apigenin (peak 35), were tentatively identified to constitute the effective antioxidant component group with a mass ratio 3∶2∶2∶ 1∶1 in Trichosanthes extract. The prepared mixed solutions of antioxidant effective component group (6.12, 2.04, and 0.68 µg/mL) showed clearance rates of DPPH · of 65.4%, 64.0% and 61.0%, and clearance rates of O2-· of 12.9%, 9.5% and 8.3%, respectively. CONCLUSION: We identified the material basis for the antioxidant activity of Trichosanthes and screened the antioxidant effective component group in Trichosanthes extract.


Assuntos
Trichosanthes , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Luteolina , Extratos Vegetais/farmacologia , Trichosanthes/química
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(9): 875-884, 2019 Sep 06.
Artigo em Chinês | MEDLINE | ID: mdl-31474067

RESUMO

With the rapid economic development and dramatic changes in lifestyle, the prevalence of overweight and obesity in China has been increasing significantly and become a serious public health threat. This article introduced the main contents of "China Blue Paper on Obesity Prevention and Control", aiming to facilitate understanding and applications of the "China Blue Paper on Obesity Prevention and Control" by policymakers, researchers and practitioners in related fields. Built upon these, recommendations were made for obesity screening, diagnosis, treatment and management, prevention and control policies and strategies, and future research priorities in China.


Assuntos
Política de Saúde , Obesidade , Sobrepeso , China/epidemiologia , Humanos , Estilo de Vida , Programas de Rastreamento , Obesidade/epidemiologia , Obesidade/prevenção & controle , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Prevalência
5.
Br J Surg ; 104(10): 1372-1381, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28632890

RESUMO

BACKGROUND: A critical appraisal of the benefits of minimally invasive surgery (MIS) is needed, but is lacking. This study examined the associations between MIS and 30-day postoperative outcomes including complications graded according to the Clavien-Dindo classification, unplanned readmissions, hospital stay and mortality for five common surgical procedures. METHODS: Patients undergoing appendicectomy, colectomy, inguinal hernia repair, hysterectomy and prostatectomy were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Non-parsimonious propensity score methods were used to construct procedure-specific matched-pair cohorts that reduced baseline differences between patients who underwent MIS and those who did not. Bonferroni correction for multiple comparisons was applied and P < 0·006 was considered significant. RESULTS: Of the 532 287 patients identified, 53·8 per cent underwent MIS. Propensity score matching yielded an overall sample of 327 736 patients (appendicectomy 46 688, colectomy 152 114, inguinal hernia repair 59 066, hysterectomy 59 066, prostatectomy 10 802). Within the procedure-specific matched pairs, MIS was associated with significantly lower odds of Clavien-Dindo grade I-II, III and IV complications (P ≤ 0·004), unplanned readmissions (P < 0·001) and reduced hospital stay (P < 0·001) in four of the five procedures studied, with the exception of inguinal hernia repair. The odds of death were lower in patients undergoing MIS colectomy (P < 0·001), hysterectomy (P = 0·002) and appendicectomy (P = 0·002). CONCLUSION: MIS was associated with significantly fewer 30-day postoperative complications, unplanned readmissions and deaths, as well as shorter hospital stay, in patients undergoing colectomy, prostatectomy, hysterectomy or appendicectomy. No benefits were noted for inguinal hernia repair.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Readmissão do Paciente , Complicações Pós-Operatórias/mortalidade , Apendicectomia/efeitos adversos , Apendicectomia/economia , Colectomia/efeitos adversos , Colectomia/economia , Gastos em Saúde , Herniorrafia/efeitos adversos , Herniorrafia/economia , Humanos , Histerectomia/efeitos adversos , Histerectomia/economia , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Readmissão do Paciente/economia , Complicações Pós-Operatórias/economia , Pontuação de Propensão , Prostatectomia/efeitos adversos , Prostatectomia/economia , Resultado do Tratamento , Estados Unidos
6.
Eur J Surg Oncol ; 43(4): 815-822, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27692535

RESUMO

BACKGROUND: Local tumour ablation (LTA) may yield better perioperative outcomes than partial nephrectomy (PN), however the impact of each treatment on perioperative mortality and health care expenditures is unknown. The aim of the study was to compare mortality, morbidity and health care expenditures between LTA and PN. PATIENTS AND METHODS: A population-based assessment of 2471 patients with cT1a kidney cancer treated with either LTA or PN, between 2000 and 2009, in the SEER-Medicare database was performed. After propensity score matching, 30-day mortality, overall and specific complication rates, length of stay, readmission rates and health care expenditures according to LTA or PN were estimated. Multivariable logistic and linear models addressed the effect of each specific LTA approach on overall complication rates, length of stay, readmission rates and health care expenditures. RESULTS: The 30-day mortality was <2% after either LTA or PN (OR 2.27, p = 0.2). The overall complication rate was 21% after LTA and 40% after PN (OR 0.38, p < 0.001). Blood transfusions, infection/sepsis, wound infections, respiratory complications, gastrointestinal complications, acute kidney injury, and accidental puncture or laceration/foreign body left during procedure rates resulted lower after LTA relative to PN (all p < 0.05). Similarly, length of stay and health care expenditures resulted lower after LTA relative to PN (all p < 0.05). Conversely, readmission rate was not significantly different in LTA relative to PN (p = 0.1). CONCLUSIONS: Despite similar perioperative mortality, LTA is associated with lower complications rate, shorter length of stay and lower health care expenditure relative to PN.


Assuntos
Carcinoma de Células Renais/cirurgia , Ablação por Cateter/métodos , Gastos em Saúde , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Injúria Renal Aguda/economia , Injúria Renal Aguda/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue/economia , Transfusão de Sangue/estatística & dados numéricos , Carcinoma de Células Renais/economia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/economia , Feminino , Humanos , Doença Iatrogênica/economia , Doença Iatrogênica/epidemiologia , Neoplasias Renais/economia , Laparoscopia , Laparotomia , Modelos Lineares , Modelos Logísticos , Masculino , Medicare , Mortalidade , Análise Multivariada , Nefrectomia/efeitos adversos , Nefrectomia/economia , Complicações Pós-Operatórias/economia , Pontuação de Propensão , Doenças Respiratórias/economia , Doenças Respiratórias/epidemiologia , Estudos Retrospectivos , Programa de SEER , Sepse/economia , Sepse/epidemiologia , Infecção da Ferida Cirúrgica/economia , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do Tratamento , Estados Unidos/epidemiologia
8.
Eur J Surg Oncol ; 40(12): 1738-45, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25454826

RESUMO

INTRODUCTION: Existing radical cystectomy (RC) perioperative mortality estimates may underestimate the contemporary rates due to more advanced age, more baseline comorbidities and potentially broader inclusion criteria for RC, relative to past criteria. METHODS: Within the most recent Surveillance, Epidemiology, and End Results (SEER)-Medicare database we identified clinically non-metastatic, muscle-invasive (T2-T4a) urothelial carcinoma of the urinary bladder (UCUB) patients, who underwent RC between 1991 and 2009. Mortality at 30- and 90-day after RC was quantified. Multivariable logistic regression analyses tested predictors of 90-day mortality. RESULTS: Within 5207 assessable RC patients 30- and 90-day mortality rates were 5.2 and 10.6%, respectively. According to age 65-69, 70-79 and ≥ 80 years, 90-day mortality rates were 6.4, 10.1 and 14.8% (p < 0.001). Additionally, 90-day mortality rates increased with increasing Charlson Comorbidity Index (CCI, 0, 1, 2 and ≥ 3): 6.3, 10.3, 12.6 and 15.9% (p < 0.001). 90-day mortality rate in unmarried patients was 13.0 vs. 9.3% in married individuals (p < 0.001). In multivariable logistic regression analyses, advanced age, higher CCI, low socioeconomic status, unmarried status and non organ-confined stage were independent predictors of 90-day mortality (all p < 0.05). CONCLUSIONS: The contemporary SEER-Medicare derived 90-day mortality rates are substantially higher than previously reported estimates from centers of excellence, and even exceed previous SEER reports. More advanced age, higher CCI score, and other patient characteristics that distinguish the current population from others account for these differences.


Assuntos
Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/cirurgia , Cistectomia , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Estudos de Coortes , Comorbidade , Cistectomia/métodos , Feminino , Humanos , Modelos Logísticos , Masculino , Estado Civil , Medicare , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Fatores de Risco , Programa de SEER , Classe Social , Estados Unidos/epidemiologia , Neoplasias da Bexiga Urinária/patologia
9.
J Insect Sci ; 14: 159, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25347844

RESUMO

When an insect hovers or performs constant-speed flight, its wings flap at certain amplitude, frequency, angle of attack, etc., and the flight is balanced (vertical force equals to the weight, and horizontal force and pitch moment are zero). It is possible that when some other sets of values of wing kinematical parameters are used, the force and moment balance conditions can still be satisfied. Does the wing kinematics used by a constant-speed flying insect minimize the power expenditure? In this study, whether the wing kinematics used by a freely hovering dronefly minimizes its energy expenditure was investigated. First, the power consumption using the set of values of wing kinematical parameters that was actually employed by the insect was computed. Then, the kinematical parameters were changed while keeping the equilibrium flight conditions satisfied, and the power consumption was recalculated. It was found that wing kinematical parameters used by the freely hovering dronefly are very close to that minimize its energy consumption, and they can ensure the margin of controllability from hovering to maneuvers. That is, slight change of wing kinematical parameters did not cause significant change of the specific power (maintained a relatively small value).


Assuntos
Dípteros/fisiologia , Voo Animal , Asas de Animais/fisiologia , Animais , Fenômenos Biomecânicos , Dípteros/anatomia & histologia , Metabolismo Energético , Modelos Biológicos , Asas de Animais/anatomia & histologia
10.
Br J Cancer ; 111(2): 213-9, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25003663

RESUMO

BACKGROUND: Pelvic lymph node dissection in patients undergoing radical prostatectomy for clinically localised prostate cancer is not without morbidity and its therapeutical benefit is still a matter of debate. The objective of this study was to develop a model that allows preoperative determination of the minimum number of lymph nodes needed to be removed at radical prostatectomy to ensure true nodal status. METHODS: We analysed data from 4770 patients treated with radical prostatectomy and pelvic lymph node dissection between 2000 and 2011 from eight academic centres. For external validation of our model, we used data from a cohort of 3595 patients who underwent an anatomically defined extended pelvic lymph node dissection. We estimated the sensitivity of pathological nodal staging using a beta-binomial model and developed a novel clinical (preoperative) nodal staging score (cNSS), which represents the probability that a patient has lymph node metastasis as a function of the number of examined nodes. RESULTS: In the development and validation cohorts, the probability of missing a positive lymph node decreases with increase in the number of nodes examined. A 90% cNSS can be achieved in the development and validation cohorts by examining 1-6 nodes in cT1 and 6-8 nodes in cT2 tumours. With 11 nodes examined, patients in the development and validation cohorts achieved a cNSS of 90% and 80% with cT3 tumours, respectively. CONCLUSIONS: Pelvic lymph node dissection is the only reliable technique to ensure accurate nodal staging in patients treated with radical prostatectomy for clinically localised prostate cancer. The minimum number of examined lymph nodes needed for accurate nodal staging may be predictable, being strongly dependent on prostate cancer characteristics at diagnosis.


Assuntos
Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prostatectomia , Neoplasias da Próstata/cirurgia , Medição de Risco
11.
Diabet Med ; 31(5): 624-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24344813

RESUMO

AIMS: To assess pre-hospital patient delay and its associated variables in patients with diabetic foot problems. METHODS: We classified 270 patients with diabetic foot problems retrospectively based on the distribution of pre-hospital delay. Clinical, demographic and socio-economic data were collected. Logistic regression analysis was performed to examine independent associations with patient delay. RESULTS: The median pre-hospital delay time was 46.49 days. Patients reported short (≤ 1 week; 77 patients, 28.5%), moderate (> 1 week and ≤ 1 month; 106 patients, 39.3%) and long delays (> 1 month; 87 patients, 32.2%). In a univariate analysis, nine variables were associated with a longer delay (P < 0.05): (1) no previous ulcer; (2) no health insurance; (3) poor housing conditions; (4) low income level; (5) low educational level; (6) infrequent foot inspection; (7) few follow-up medical visits; (8) absence of diabetic foot education; (9) lack of knowledge of foot lesion warning signals. A multivariate analysis showed that absence of diabetic foot education (odds ratio 2.70, 95% CI 1.03-7.06, P = 0.043) and lack of knowledge of foot lesion warning signals (odds ratio 2.14, 95% CI 1.16-3.94, P = 0.015) were independent predictors of long patient delay. Long delay increased the risk of amputation (odds ratio 2.22, 95% CI 1.36-3.64, P = 0.002) and mortality (odds ratio 2.69, 95% CI 1.35-5.33, P = 0.005). CONCLUSIONS: A number of factors were involved in pre-hospital delay among patients with diabetic foot problems and contributed to poor outcomes. We recommend developing a community intervention programme that targets at-risk communities to encourage earlier multidisciplinary team assessment to reduce disparities and improve foot outcomes in patients with diabetes.


Assuntos
Complicações do Diabetes/complicações , Complicações do Diabetes/terapia , Pé Diabético/etiologia , Pé Diabético/terapia , Qualidade da Assistência à Saúde/normas , Tempo para o Tratamento , Idoso , China , Estudos Transversais , Escolaridade , Feminino , Hospitalização , Humanos , Seguro Saúde , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Análise de Regressão , Estudos Retrospectivos , Classe Social , Fatores de Tempo , Resultado do Tratamento
12.
Med Phys ; 39(6Part27): 3951, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28519992

RESUMO

PURPOSE: Monte Carlo simulations of DQE(f) can greatly aid in the design of scintillator-based detectors by helping optimize key parameters including scintillator material and thickness, pixel size, surface finish, and septa reflectivity. However, the additional optical transport significantly increases simulation times, necessitating a large number of parallel processors to adequately explore the parameter space. To address this limitation, we have optimized the DQE(f) algorithm, reducing simulation times per design iteration to 10 minutes on a single CPU. METHODS: DQE(f) is proportional to the ratio, MTF(f)̂2 /NPS(f). The LSF-MTF simulation uses a slanted line source and is rapidly performed with relatively few gammas launched. However, the conventional NPS simulation for standard radiation exposure levels requires the acquisition of multiple flood fields (nRun), each requiring billions of input gamma photons (nGamma), many of which will scintillate, thereby producing thousands of optical photons (nOpt) per deposited MeV. The resulting execution time is proportional to the product nRun x nGamma x nOpt. In this investigation, we revisit the theoretical derivation of DQE(f), and reveal significant computation time savings through the optimization of nRun, nGamma, and nOpt. Using GEANT4, we determine optimal values for these three variables for a GOS scintillator-amorphous silicon portal imager. Both isotropic and Mie optical scattering processes were modeled. Simulation results were validated against the literature. RESULTS: We found that, depending on the radiative and optical attenuation properties of the scintillator, the NPS can be accurately computed using values for nGamma below 1000, and values for nOpt below 500/MeV. nRun should remain above 200. Using these parameters, typical computation times for a complete NPS ranged from 2-10 minutes on a single CPU. CONCLUSIONS: The number of launched particles and corresponding execution times for a DQE simulation can be dramatically reduced allowing for accurate computation with modest computer hardware. NIHRO1 CA138426. Several authors work for Varian Medical Systems.

13.
Phys Med Biol ; 55(22): 6695-720, 2010 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-21030750

RESUMO

Accurate scatter correction is required to produce high-quality reconstructions of x-ray cone-beam computed tomography (CBCT) scans. This paper describes new scatter kernel superposition (SKS) algorithms for deconvolving scatter from projection data. The algorithms are designed to improve upon the conventional approach whose accuracy is limited by the use of symmetric kernels that characterize the scatter properties of uniform slabs. To model scatter transport in more realistic objects, nonstationary kernels, whose shapes adapt to local thickness variations in the projection data, are proposed. Two methods are introduced: (1) adaptive scatter kernel superposition (ASKS) requiring spatial domain convolutions and (2) fast adaptive scatter kernel superposition (fASKS) where, through a linearity approximation, convolution is efficiently performed in Fourier space. The conventional SKS algorithm, ASKS, and fASKS, were tested with Monte Carlo simulations and with phantom data acquired on a table-top CBCT system matching the Varian On-Board Imager (OBI). All three models accounted for scatter point-spread broadening due to object thickening, object edge effects, detector scatter properties and an anti-scatter grid. Hounsfield unit (HU) errors in reconstructions of a large pelvis phantom with a measured maximum scatter-to-primary ratio over 200% were reduced from -90 ± 58 HU (mean ± standard deviation) with no scatter correction to 53 ± 82 HU with SKS, to 19 ± 25 HU with fASKS and to 13 ± 21 HU with ASKS. HU accuracies and measured contrast were similarly improved in reconstructions of a body-sized elliptical Catphan phantom. The results show that the adaptive SKS methods offer significant advantages over the conventional scatter deconvolution technique.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Processamento de Imagem Assistida por Computador/métodos , Espalhamento de Radiação , Algoritmos , Análise de Fourier , Método de Monte Carlo , Imagens de Fantasmas
14.
Am J Clin Nutr ; 73(2): 308-15, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11157329

RESUMO

BACKGROUND: Body composition and resting energy expenditure (REE) have not been examined longitudinally during puberty. OBJECTIVE: The purpose of this longitudinal study was to examine the influence of pubertal maturation on REE relative to body composition in African American and white children. DESIGN: The study included 92 white and 64 African American children (mean age at baseline: 8.3 and 7.9 y, respectively) from Birmingham, AL. The children had 2-5 annual measurements of fat mass (FM), lean mass (LM), and REE. The Tanner stages of the children ranged from 1 to 5. Mixed-model repeated-measures analyses were used to test the change in REE relative to body composition with increasing Tanner stage among ethnic and sex groups. RESULTS: LM increased from Tanner stage 1 to subsequent stages. FM relative to LM decreased from Tanner stage 1 to stages 3, 4, and 5 but not from stage 1 to stage 2. The African American children had relatively higher limb LM and lower trunk LM than did the white children. REE declined with Tanner stage after adjustment for ethnicity, sex, FM, and LM. This decline was significant from Tanner stage 1 to stages 3, 4, and 5 but not to Tanner stage 2. After adjustment for age, Tanner stage, FM, and LM or LM distribution, REE was significantly higher in white than in African American children (by approximately 250 kJ/d). CONCLUSION: In a large sample of children at various Tanner stages, we found an ethnic difference in REE after adjustment for age, Tanner stage, FM, and LM that was not explained by the difference in LM distribution.


Assuntos
Metabolismo Basal , População Negra , Composição Corporal , Puberdade/metabolismo , População Branca , Metabolismo Basal/genética , População Negra/genética , Composição Corporal/genética , Constituição Corporal , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Puberdade/genética , Maturidade Sexual , População Branca/genética
15.
16.
Pediatrics ; 106(4): E50, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015545

RESUMO

BACKGROUND: Low levels of energy expenditure and aerobic fitness have been hypothesized to be risk factors for obesity. Longitudinal studies to determine whether energy expenditure influences weight gain in whites have provided conflicting results. To date, no studies have examined this relationship in blacks or whether aerobic fitness influences weight gain in white or black children. METHODS: One hundred fifteen children, 72 white (55 girls and 17 boys) and 43 black (24 girls and 19 boys) were recruited for this study. Aerobic fitness, resting, total, and activity-related energy expenditure and body composition were measured at baseline. The children returned annually for 3 to 5 repeated measures of body composition. The influence of the initial measures of energy expenditure and fitness on the subsequent rate of increase in adiposity was examined, adjusting for initial body composition, age, ethnicity, gender, and Tanner stage. Because 20 children did not attain maximum oxygen consumption, the sample size for the combined analysis was 95. RESULTS: Initial fat mass was the main predictor of increasing adiposity in this cohort of children, with greater initial fat predicting a higher rate of increase of adiposity. There was also a significant negative relationship between aerobic fitness and the rate of increasing adiposity (F(1,82) = 3.92). With every increase of.1 L/minute of fitness, there was a decrease of.081 kg fat per kg of lean mass gained. None of the measures of energy expenditure significantly predicted increasing adiposity in white or black children. CONCLUSIONS: Initial fat mass was the dominant factor influencing increasing adiposity; however, aerobic fitness was also a significant independent predictor of increasing adiposity in this cohort of children. Resting, total, or activity-related energy expenditure did not predict increasing adiposity. It seems that aerobic fitness may be more important than absolute energy expenditure in the development of obesity in white or black children. energy expenditure, fitness, longitudinal, obesity.


Assuntos
Tecido Adiposo , Metabolismo Energético , Aptidão Física , Metabolismo Basal , População Negra , Composição Corporal , Criança , Pré-Escolar , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Consumo de Oxigênio , Análise de Regressão , População Branca
17.
Ann Biomed Eng ; 27(5): 592-606, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10548329

RESUMO

In this paper, we investigate two general methods of modeling and prediction which have been applied to neurobiological systems, the orthogonal search (OS) method and the canonical variate analysis (CVA) approach. In these methods, nonlinear autoregressive moving average with observed inputs (ARX) and state affine models are developed as one step predictors by minimizing the mean-squared-error. An unknown nonlinear time-invariant system is assumed to have the Markov property of finite order so that the one step predictors are finite dimensional. No special assumptions are made about model terms, model order or state dimensions. Three examples are presented. The first is a numerical example which demonstrates the differences between the two methods, while the last two examples are computer simulations for a bilinear system and the Lorenz attractor which can serve as a model for the EEG. These two methods produce comparable results in terms of minimizing the mean-square-error; however, the OS method produces an ARX model with fewer terms, while the CVA method produces a state model with fewer state dimensions.


Assuntos
Cadeias de Markov , Modelos Neurológicos , Dinâmica não Linear , Eletroencefalografia
18.
Obes Res ; 7(4): 387-94, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10440595

RESUMO

OBJECTIVE: The morbid obesity associated with Prader-Willi syndrome (PWS) may result from either excessive energy intake or reduced energy expenditure (EE). In this report, we describe the development and validation of an Activity-Energy Measurement System (AEMS) to measure EE and physical activity components in an environment approximating free-living conditions. RESEARCH METHODS AND PROCEDURES: The AEMS consists of a live-in, whole-room indirect calorimeter equipped with a novel force platform floor system to enable simultaneous measurements of EE, physical activity, and work efficiency during spontaneous activities and standardized exercises. Free-living physical activity and estimated free-living EE are measured using portable triaxial accelerometers individually calibrated in each subject during their stay in the AEMS. RESULTS: Representative data from two PWS patients and two matched control (CTR) subjects displayed EE during their inactive lifestyles. DISCUSSION: This combination of methods will allow the quantification of daily EE and its components, the amount and energy cost of physical activity, and the relationships between body composition and EE, in order to determine their roles in the development and maintenance of the morbid obesity in PWS.


Assuntos
Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Síndrome de Prader-Willi/fisiopatologia , Adolescente , Adulto , Calorimetria Indireta/métodos , Criança , Feminino , Humanos , Masculino , Obesidade Mórbida/fisiopatologia , Síndrome de Prader-Willi/metabolismo , Estatísticas não Paramétricas
19.
Med Care Res Rev ; 56(2): 156-76, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10373722

RESUMO

This study further examines the relationship between strategic group membership and performance in the nursing home industry. The results indicate seven strategic groups in the industry with significant between-group differences in operating margin, average profit per patient day, catheterization rate, health deficiencies, life and safety deficiencies, and efficiency in the provision of services. The authors did not, however, find significant between-group differences in pressure sore rate, the use of restraints, or in the percentage of patients with significant unplanned weight changes. The group with the highest private-pay utilization combined with high Medicare utilization generally performed the best along all indicators. Results also suggest that strategic group membership and rural/urban location have a greater impact on performance than do ownership, chain membership, or possession of a dedicated specialty care unit.


Assuntos
Tomada de Decisões Gerenciais , Competição Econômica/organização & administração , Casas de Saúde/classificação , Casas de Saúde/organização & administração , Técnicas de Planejamento , Análise de Variância , Análise por Conglomerados , Eficiência Organizacional , Auditoria Financeira , Florida , Pesquisa sobre Serviços de Saúde , Humanos , Casas de Saúde/economia , Casas de Saúde/normas , Propriedade , Indicadores de Qualidade em Assistência à Saúde , Gestão da Qualidade Total
20.
Am J Clin Nutr ; 69(5): 898-903, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10232628

RESUMO

BACKGROUND: Over the past decade, considerable attention has been paid to accurately measuring body composition in diverse populations. Recently, the use of air-displacement plethysmography (AP) was proposed as an accurate, comfortable, and accessible method of body-composition analysis. OBJECTIVE: The purpose of this study was to compare measurements of percentage body fat (%BF) by AP and 2 other established techniques, hydrostatic weighing (HW) and bioelectrical impedance analysis (BIA), in adults. DESIGN: The sample consisted of healthy men (n = 23) and women (n = 24). %BF was measured by AP, HW, and BIA. RESULTS: In the total group, %BF(AP) (25.0+/-8.9%) was not significantly different from %BF(HW) (25.1+/-7.7%) or %BF(BIA) (23.9+/-7.7%), and %BF(AP) was significantly correlated with %BF(HW) (r = 0.944, P < 0.001) and with %BF(BIA) (r = 0.859, P < 0.01). Compared with HW, AP underestimated %BF in men (by -1.24+/-3.12%) but overestimated %BF in women (by 1.02+/-2.48%), indicating a significant sex effect (P < 0.05). The differences in estimation between AP and BIA and between BIA and HW were not significantly different between the sexes. CONCLUSION: AP is an accurate method for assessing body composition in healthy adults. Future studies should assess further the cause of the individual variations with this new method.


Assuntos
Composição Corporal , Pletismografia/métodos , Tecido Adiposo , Adulto , Ar , Feminino , Humanos , Pressão Hidrostática , Masculino , Pessoa de Meia-Idade , Pletismografia de Impedância
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