Association of pellicle growth morphological characteristics and clinical presentation of Mycobacterium tuberculosis isolates

Trehalose dimycolate (TDM) is a mycobacterial glycolipid that is released from the surface of virulent M. tuberculosis. We evaluated the rate of growth, colony characteristics and production of TDM by Mycobacterium tuberculosis strains isolated from different clinical sites. Since detergent removes TDM from organisms, we analyzed growth rate and colony morphology of 79 primary clinical isolates grown as pellicles on the surface of detergent free Middlebrook 7H9 media. The genotype of each had been previously characterized. TDM production was measured by thin layer chromatography on 32 of these isolates. We found that strains isolated from pulmonary sites produced large amounts of TDM, grew rapidly as thin spreading pellicles, showed early cording (<1 week) and climbed the sides of the dish. In contrast, the extrapulmonary isolates (lymph node and bone marrow) produced less TDM (p<0.01), grew as discrete patches with little tendency to spread or climb the walls (p<0.02). The Beijing pulmonary (BP) isolates produced more TDM than non Beijing pulmonary isolates. The largest differences were observed in Beijing strains. The Beijing pulmonary isolates produced more TDM and grew faster than the Beijing extrapulmonary isolates (p<0.01). This was true even when the pulmonary and extrapulmonary isolates were derived from the same clade. These growth characteristics were consistently observed only on the first passage after primary isolation. This suggests that the differences in growth rate and TDM production observed reflect differences in gene expression patterns of pulmonary and extrapulmonary infections, that Mycobacterium tuberculosis in the lung grows more rapidly and produces more TDM than it does in extrapulmonary sites. This provides new opportunities to investigate gene expression of Mycobacterium tuberculosis in human.^

Assessing pediatric nasal carriage of S. aureus & MRSA

Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) has become an increasing problem in the community. Nasal carriage of these bacteria has been shown to be a predisposing factor for infection and environmental contamination. This serious public health concern prompted an investigation to assess the pediatric nasal carriage of these bacteria in an effort to better understand the populations at risk and prevention of infection.^ This prospective study surveys 30 children from the Northwest Assistance Ministries (NAM) pediatric clinic from October 2008 to the present. Two nasal swabs were taken in 2-4 week intervals to determine S. aureus carrier status. Microbiologic tests were conducted to isolate and identify S. aureus from nasal cultures. Children with 2 cultures positive for S. aureus were classified as persistent carriers, those with 1 positive and 1 negative culture were classified as intermittent carriers, and those with 2 negative cultures were classified as noncarriers. This information was related to patient records and statistical analyses (X 2 and t-tests) were performed.^ Distribution of S. aureus carriage related to patient demographics (age, sex, & race) was showed no significant differences between S. aureus positive and S. aureus negative patient populations (p = 0.8). Additionally, the distribution of carrier status related to demographics also showed no significant difference (p = 0.8). Finally, the distribution of carrier status related to relevant medical history (immunizations current, past infection, & antibiotic use at time of swabbing) showed no significant difference (p = 0.4).^ This study is a snapshot of an ongoing study to assess the pediatric nasal carriage of S. aureus and MRSA. The inability to draw any reliable conclusion from the distribution of data is likely a result of an inadequate samples size. This is one of few studies assessing pediatric nasal carriage of S. aureus and targeting an underrepresented, Hispanic population is especially unique. Continuing this study allows for a better understanding of the epidemiology of this bacterium which will hopefully lead to appropriate interventions thus preventing future S. aureus infections.^

The seroprevalence of Rocky Mountain spotted fever in shelter dogs in Harris County

Rocky Mountain spotted fever (RMSF) is a tick-borne illness caused by the bacteria Rickettsia rickettsii, with infections occurring in humans and dogs. The prominent tick vector of RMSF, Dermacantor variabilis, and another potential vector, Rhipacephalus sanguineus, are prevalent in Texas. The goal of this study was to determine the prevalence of past infections by testing for IgG antibodies to R. rickettsii in dogs in an animal shelter in Harris County using an immunofluorescence assay (IFA) test. We found that 12.6% (24) of 191 dogs tested had a positive IFA test at 1:64 serum dilution, indicating infection at some time in the past. We also sampled the ticks present on dogs in the animal shelter to understand the prevalence of potential vector species. Of a total of 58 ticks, 86% were D. variabilis and the remaining 14% were R. sanguineus. The results of this study demonstrate that RMSF has the potential to be, and may already be, endemic to the Harris County area. Public health actions such as heightened surveillance and education that RMSF is present would be appropriate in the Harris County area.^

A systematic review of economic evaluations for interventions of cardiovascular diseases

Background. Cardiovascular disease (CVD) exhibits the most striking public health significance due to its high prevalence and mortality as well as huge economic burdens all over the world, especially in industrialized countries. Major risk factors of CVDs have been the targets of population-wide prevention in the United States. Economic evaluations provide structured information in regard to the efficiency of resource utilization which can inform decisions of resource allocation. The main purpose of this review is to investigate the pattern of study design of economic evaluations for interventions of CVDs. ^ Methods. Primary journal articles published during 2003-2008 were systematically retrieved via relevant keywords from Medline, NHS Economic Evaluation Database (NHS EED) and EBSCO Academic Search Complete. Only full economic evaluations for narrowly defined CVD interventions were included for this review. The methodological data of interest were extracted from the eligible articles and reorganized in Microsoft Access database. Chi-square tests in SPSS were used to analyze the associations between pairs of categorical data. ^ Results. One hundred and twenty eligible articles were reviewed after two steps of literature selection with explicit inclusion and exclusion criteria. Descriptive statistics were reported regarding the evaluated interventions, outcome measures, unit costing and cost reports. The chi-square test of the association between prevention level of intervention and category of time horizon showed no statistical significance. The chi-square test showed that sponsor type was significantly associated with whether new or standard intervention being concluded as more cost effective. ^ Conclusions. Tertiary prevention and medication interventions are the major interests for economic evaluators. The majority of the evaluations were claimed from either a provider’s or a payer’s perspective. Almost all evaluations adopted gross costing strategy for unit cost data rather than micro costing. EQ-5D is the most commonly used instrument for subjective outcome measurement. More than half of the evaluations used decision analytic modeling techniques. The lack of consistency in study design standards in published evaluations appears in several aspects. Prevention level of intervention is not likely to be a factor for evaluators to decide whether to design an evaluation in a lifetime horizon or not. Published evaluations sponsored by industry are more likely to conclude that new intervention is more cost effective than standard intervention.^

Ethnic differences in tumor characteristics, treatment and survival in glioma patients

Purpose. A descriptive analysis of glioma patients by race was carried out in order to better elucidate potential differences between races in demographics, treatment, characteristics, prognosis and survival. ^ Patients and Methods. Among 1,967 patients ≥ 18 years diagnosed with glioma seen between July 2000 and September 2006 at The University of Texas M.D. Anderson Cancer Center (UTMDACC). Data were collated from the UTMDACC Patient History Database (PHDB) and the UTMDACC Tumor Registry Database (TRDB). Chi-square analysis, uni- /multivariate Cox proportional hazards modeling and survival analysis were used to analyze differences by race. ^ Results. Demographic, treatment and histologic differences exist between races. Though risk differences were seen between races, race was not found to be a significant predictor in multivariate regression analysis after accounting for age, surgery, chemotherapy, radiation, tumor type as stratified by WHO tumor grade. Age was the most consistent predictor in risk for death. Overall survival by race was significantly different (p=0.0049) only in low-grade gliomas after adjustment for age although survival differences were very slight. ^ Conclusion. Among this cohort of glioma patients, age was the strongest predictor for survival. It is likely that survival is more influenced by age, time to treatment, tumor grade and surgical expertise rather than racial differences. However, age at diagnosis, gender ratios, histology and history of cancer differed significantly between race and genetic differences to this effect cannot be excluded. ^

Involvement of lipocalin 2 in leukemia and breast cancer

Human lipocalin 2 is described as the neutrophil gelatinase-associated lipocalin (NGAL). The lipocalin 2 gene encodes a small, secreted glycoprotein that possesses a variety of functions, of which the best characterized function is organic iron binding activity. Elevated NGAL expression has been observed in many human cancers including breast, colorectal, pancreatic and ovarian cancers. I focused on the characterization of NGAL function in chronic myelogenous leukemia (CML) and breast cancer. Using the leukemic xenograft mouse model, we demonstrated that over-expression of NGAL in K562 cells, a leukemic cell line, led to a higher apoptotic rate and an atrophy phenotype in the spleen of inoculated mice compared to K562 cells alone. These results indicate that NGAL plays a primary role in suppressing hematopoiesis by inducing apoptosis within normal hematopoietic cells. In the breast cancer project, we analyzed two microarray data sets of breast cancer cell lines ( n = 54) and primary breast cancer samples (n = 318), and demonstrated that high NGAL expression is significantly correlated with several tumor characteristics, including negative estrogen receptor (ER) status, positive HER2 status, high tumor grade, and lymph node metastasis. Ectopic NGAL expression in non-aggressive (ZR75.1 and MCF7) cells led to aggressive tumor phenotypes in vitro and in vivo. Conversely, knockdown of NGAL expression in various breast cancer cell lines by shRNA lentiviral infection significantly decreased migration, invasion, and metastasis activities of tumor cells both in vitro and in vivo . It has been previously reported that transgenic mice with a mutation in the region of trans-membrane domain (V664E) of HER2 develop mammary tumors that progress to lung metastasis. However, we observed that genetic deletion of the 24p3 gene, a mouse homolog of NGAL, in HER2 transgenic mice by breeding with 24p3-null mice resulted in a significant delay of mammary tumor formation and reduction of lung metastasis. Strikingly, we also found that treatment with affinity purified 24p3 antibodies in the 4T1 breast cancer mice strongly reduced lung metastasis. Our studies provide evidence that NGAL plays a critical role in breast cancer development and progression, and thus NGAL has potential as a new therapeutic target in breast cancer.^

Aedes aegypti, Aedes albopictus, and Dengue virus in Harris county: An estimate of risk

Recent outbreaks of dengue fever (DF) along the United States/Mexico border, coupled with the high number of reported cases in Mexico suggest that there is the possibility for DF emergence in Houston, Texas1,2. To determine the presence of DF, populations of Aedes aegypti and Aedes albopictus were identified and tested for dengue virus. Maps were created to identify "hot spots" (Figure 1) based on historical data on Ae. aegypti and Ae. albopictus, demographic information, and locations of human cases of dengue fever. BG Sentinel Traps®, in conjunction with BG Lure® attractant, octanol and dry ice, were used to collect mosquitoes, which were then tested for presence of dengue virus using ELISA techniques. All samples tested were negative for dengue virus (DV). Survival of DV ultimately comes down to whether or not it will be vectored by a mosquito to a susceptible human host. The presence of infected humans and contact with the mosquito vectors are two critical factors necessary in the establishment of DF. Historical records indicate the presence of Ae. aegypti and Ae. albopictus in Harris County, which would support localized dengue transmission if infected individuals are present.^ (1) Brunkard JM, Robles-Lopez JL, Ramirez J, Cifuentes E, Rothenberg SJ, Hunsperger EA, Moore CG, Brussolo RM, Villarreal NA, Haddad BM, 2007. Dengue fever seroprevalence and risk factors, Texas-Mexico border, 2004. Emerg Infect Dis 13: 1477-1483. (2) Ramos MM, Mohammed H, Zielinski-Gutierrez E, Hayden MH, Lopez JL, Fournier M, Trujillo AR, Burton R, Brunkard JM, Anaya-Lopez L, Banicki AA, Morales PK, Smith B, Munoz JL, Waterman SH, 2008. Epidemic dengue and dengue hemorrhagic fever at the Texas-Mexico Border: results of a household-based seroepidemiologic survey, December 2005. Am J Trop Med Hyg 78: 364-369.^

Systematic review of genetic risk score in coronary heart disease and other diseases

In order to better take advantage of the abundant results from large-scale genomic association studies, investigators are turning to a genetic risk score (GRS) method in order to combine the information from common modest-effect risk alleles into an efficient risk assessment statistic. The statistical properties of these GRSs are poorly understood. As a first step toward a better understanding of GRSs, a systematic analysis of recent investigations using a GRS was undertaken. GRS studies were searched in the areas of coronary heart disease (CHD), cancer, and other common diseases using bibliographic databases and by hand-searching reference lists and journals. Twenty-one independent case-control studies, cohort studies, and simulation studies (12 in CHD, 9 in other diseases) were identified. The underlying statistical assumptions of the GRS using the experience of the Framingham risk score were investigated. Improvements in the construction of a GRS guided by the concept of composite indicators are discussed. The GRS will be a promising risk assessment tool to improve prediction and diagnosis of common diseases.^

Plasma homocysteine levels and Alzheimer's Disease: A systematic review

Objective. To systematically review studies published in English on the relationship between plasma total homocysteine (Hcy) levels and the clinical and/or postmortem diagnosis of Alzheimer's disease (AD) in subjects who are over 60 years old.^ Method. Medline, PubMed, PsycINFO and Academic Search Premier, were searched by using the keywords "homocysteine", "Alzheimer disease" and "dementia", and "cognitive disorders". In addition, relevant articles in PubMed using the "related articles" link and by cross-referencing were identified. The study design, study setting and study population, sample size, the diagnostic criteria of the National Institute of Neurological and Communicative Disorders and Stroke (NINCDS) and the Alzheimer's Disease and Related Disorders Association (ADRDA), and description of how Hcy levels were measured or defined had to have been clearly stated. Empirical investigations reporting quantitative data on the epidemiology of the relationship between plasma total Hcy (exposure factor) and AD (outcome) were included in the systematic review.^ Results. A total of 7 studies, which included a total of 2,989 subjects, out of 388 potential articles met the inclusion criteria: four case control and three cohort studies were identified. All 7 studies had association statistics, such as the odds ratio (OR), the relative rates (RR), and the hazard ratio (HR) of AD, examined using multivariate and logistic regression analyses. Three case - comparison studies: Clarke et al. (1998) (OR: 4.5, 95% CI.: 2.2 - 9.2); McIlroy et al. (2002) (OR: 2.9, 95% CI.: 1.00–8.1); Quadri et al. (2004) (OR: 3.7, 95% CI.: 1.1 - 13.1), and two cohort studies: Seshadri et al. (2002) (RR: 1.8, 95% CI.: 1.3 - 2.5); Ravaglia et al. (2005) (HR: 2.1, 95% CI.: 1.7 - 3.8) found a significant association between serum total Hcy and AD. One case-comparison study, Miller et al. (2002) (OR: 2.2, 95% C.I.: 0.3 -16), and one cohort study, Luchsinger et al. (2004) (HR: 1.4, 95% C.I.: 0.7 - 2.3) failed to reject H0.^ Conclusions. The purpose of this review is to provide a thorough analysis of studies that examined the relationship between Hcy levels and AD. Five studies showed a positive statistically significant association between elevated total Hcy values and AD but the association was not statistically significant in two studies. Further research is needed in order to establish evidence of the strong, consistent association between serum total Hcy and AD as well as the presence of the appropriate temporal relationship. To answer these questions, it is important to conduct more prospective studies that examine the occurrence of AD in individuals with and without elevated Hcy values at baseline. In addition, the international standardization of measurements and cut-off points for plasma Hcy levels across laboratories is a critical issue to be addressed for the conduct of future studies on the topic.^

Association of part-time employment and sexual risk-taking behaviors among middle school students

Background. Previous research shows inconsistent results as to the association between part-time employment and sexual behavior among younger teens. Studies of older teens cannot be generalized to younger teens because of the wide differences in types of work performed, nature of work environments, and work intensity. Objective. Examine the relationship between part-time employment and sexual behavior in a cross-sectional sample of public middle school students in Houston, Texas. Methods . The study presents a secondary analysis of data from the It’s Your Game…Keep it Real baseline data collection (11/2004–1/2005). It’s Your Game… is an intervention program for middle school students designed to prevent Sexually Transmitted Infections. Statistical analysis. Univariate and multivariate logistic regression analyses were conducted to examine the association between part-time employment and vaginal intercourse: (a) ever had sex; and (b) current sexual activity. Results. Overall, 13.2% of students worked for pay; male students were 1.5 times as likely as females to be working. Of all the students, 11.0% had had sexual intercourse; students who worked were 3 times more likely to be sexually experienced than those who did not. Among students who were sexually experienced, 67.0% were currently sexually active. After adjusting for the other covariates, Hispanic students were almost 3.6 times more likely to report current sexual activity compared to students in other racial/ethnic groups. In univariate analysis, students who worked 1-5 hrs/week were more likely to be sexually experienced than those not currently employed, and the likelihood increased with number of hours worked. There is a similar pattern in the multivariate model, but the odds ratios are too close for the evidence to be more than suggestive. Of sexually experienced students, students working 1-5 hrs/week were 2.7 times more likely to report current sexual intercourse than those not working; those working >5 hrs/week were 4.7 times more likely. The multivariate model showed a similar increase in likelihood, and adjustment for covariates increased these associations: students who worked 1-5 hrs/week were 3.6 times more likely to report current sexual intercourse, and students who worked >5 hrs/week were 4.5 times more likely, than students not currently employed.^

The influence of socioeconomic status on the relationship between diabetes and amputations: A systematic review of the literature

This paper synthesizes the current knowledge available regarding the impact of socioeconomic status on diabetes and amputations. In September 2009, searches in the OVID Medline and PubMed databases were performed using keywords associated with race/ethnicity, educational level, insurance status, veteran status, low income, diabetes, and lower extremity amputation. Articles published between 1996 and the search date were used. The pertinent articles were analyzed, summarized, and synthesized. ^ The majority of the articles agreed that African American, American Indian, and Latino minorities experience significantly higher rates of diabetes-related lower extremity amputation (LEA) when compared to whites. Few articles suggested that the disparity experienced by minorities and others of low SES was due to biology; most articles link it to a combination of lower income, lower educational attainment, uninsured or underinsured status, and a greater prevalence of detrimental health behaviors such as smoking. These, in turn, are linked to decreased knowledge of self-care, delayed health care seeking, delayed diagnoses and treatment, discrimination, and low quality health care. Interventions focused on patient education, established regimens of treatment, foot care, and control of diabetes have been shown to be effective, although none have lowered the rate of diabetes-related LEA to rates found in the general population.^

Does exhaled nitric oxide predict asthma exacerbation in children?

Asthma is a chronic complex disorder of the respiratory tract that affects millions of people globally, a large percentage of which are children. Triggered by a host of factors such as allergens and changes in temperature, the pathophysiologic and clinical indices vary among patients and have contributed to difficulties in overall management of asthma. Shortly after exhaled nitric oxide (eNO) was discovered in higher concentrations in asthma patients, it was shown to be superior to other markers such as PEFR, FEV1 and sputum eosinophils in screening asthma patients. Studies have also noted promising results regarding the use of eNO to predict asthma exacerbation in adults while in children, asthma symptoms have been observed to be good predictors of asthma exacerbation. Currently however, the potential of eNO as a predictor of asthma exacerbation in children is yet to be examined. The objective of this study was to assess eNO potential to predict asthma exacerbation in children by examining the relationship between eNO and changes in pulmonary function, asthma symptoms and rescue medication use.^ The primary study "Air Toxics and Asthma in Children" (ATAC), recruited children aged 9 to 14 years with labile persistent asthma diagnosed at least one year earlier. The data obtained from 30 study participants, included exhaled nitric oxide concentration, PEFR, FEV1, asthma symptoms and frequency of emergency medication use.^ Descriptive statistics, Pearson's and Spearman's correlation tests were followed by a simple linear regression in which eNO was the independent (predictor) variable while FEV1, PEFR, asthma symptoms and frequency of emergency medication use were the dependent (outcome) variables.^ Results showed that eNO was associated with percent change in FEV1, day time wheeze, night time shortness of breath, but correlated only weakly with PEFR, amplitude percent of mean PEFR, FEV1, percent change in FEV1 and asthma symptoms.^ Further research is imperative to better define the role of eNO and understand intrinsic pathologic mechanisms towards asthma management in children.^

Secondary data analysis of a pilot study of use of an instructional video for dietary assessment

Introduction. Food frequency questionnaires (FFQ) are used study the association between dietary intake and disease. An instructional video may potentially offer a low cost, practical method of dietary assessment training for participants thereby reducing recall bias in FFQs. There is little evidence in the literature of the effect of using instructional videos on FFQ-based intake. Objective. This analysis compared the reported energy and macronutrient intake of two groups that were randomized either to watch an instructional video before completing an FFQ or to view the same instructional video after completing the same FFQ. Methods. In the parent study, a diverse group of students, faculty and staff from Houston Community College were randomized to two groups, stratified by ethnicity, and completed an FFQ. The "video before" group watched an instructional video about completing the FFQ prior to answering the FFQ. The "video after" group watched the instructional video after completing the FFQ. The two groups were compared on mean daily energy (Kcal/day), fat (g/day), protein (g/day), carbohydrate (g/day) and fiber (g/day) intakes using descriptive statistics and one-way ANOVA. Demographic, height, and weight information was collected. Dietary intakes were adjusted for total energy intake before the comparative analysis. BMI and age were ruled out as potential confounders. Results. There were no significant differences between the two groups in mean daily dietary intakes of energy, total fat, protein, carbohydrates and fiber. However, a pattern of higher energy intake and lower fiber intake was reported in the group that viewed the instructional video before completing the FFQ compared to those who viewed the video after. Discussion. Analysis of the difference between reported intake of energy and macronutrients showed an overall pattern, albeit not statistically significant, of higher intake in the video before versus the video after group. Application of instructional videos for dietary assessment may require further research to address the validity of reported dietary intakes in those who are randomized to watch an instructional video before reporting diet compared to a control groups that does not view a video.^

Genetic variability and the hypothalamic control of energy balance

Background. Obesity is a major health problem throughout the industrialized world. Despite numerous attempts to curtail the rapid growth of obesity, its incidence continues to rise. Therefore, it is crucial to better understand the etiology of obesity beyond the concept of energy balance.^ Aims. The first aim of this study was to first investigate the relationship between eating behaviors and body size. The second goal was to identify genetic variation associated with eating behaviors. Thirdly, this study aimed to examine the joint relationships between eating behavior, body size and genetic variation.^ Methods. This study utilized baseline data ascertained in young adults from the Training Interventions and Genetics of Exercise (TIGER) Study. Variables assessed included eating behavior (Emotional Eating Scale, Eating Attitudes Test-26, and the Block98 Food Frequency Questionnaire), body size (body mass index, waist and hip circumference, waist/hip ratio, and percent body fat), genetic variation in genes implicated related to the hypothalamic control of energy balance, and appropriate covariates (age, gender, race/ethnicity, smoking status, and physical activity. For the genetic association analyses, genotypes were collapsed by minor allele frequency, and haplotypes were estimated for each gene. Additionally, Bayesian networks were constructed in order to determine the relationships between genetic variation, eating behavior and body size.^ Results. We report that the EAT-26 score, Caloric intake, percent fat, fiber intake, HEAT index, and daily servings of vegetables, meats, grains, and fats were significantly associated with at least one body size measure. Multiple SNPs in 17 genes and haplotypes from 12 genes were tested for their association with body size. Variation within both DRD4 and HTR2A was found to be associated with EAT-26 score. In addition, variation in the ghrelin gene (GHRL) was significantly associated with daily Caloric intake. A significant interaction between daily servings of grains and the HEAT index and variation within the leptin receptor gene (LEPR) was shown to influence body size.^ Conclusion. This study has shown that there is a substantial genetic component to eating behavior and that genetic variation interacts with eating behavior to influence body size.^

Variance of familial dietary intake

Although many family-based genetic studies have collected dietary data, very few have used the dietary information in published findings. No single solution has been presented or discussed in the literature to deal with the problem of using factor analyses for the analyses of dietary data from several related individuals from a given household. The standard statistical approach of factor analysis cannot be applied to the VIVA LA FAMILIA Study diet data to ascertain dietary patterns since this population consists of three children from each family, thus the dietary patterns of the related children may be correlated and non-independent. Addressing this problem in this project will enable us to describe the dietary patterns in Hispanic families and to explore the relationships between dietary patterns and childhood obesity. ^ In the VIVA LA FAMILIA Study, an overweight child was first identified and then his/her siblings and parents were brought in for data collection which included 24 hour recalls and food frequency questionnaire (FFQ). Dietary intake data were collected using FFQ and 24 hour recalls on 1030 Hispanic children from 319 families. ^ The design of the VIVA LA FAMILIA Study has important and unique statistical considerations since its participants are related to each other, the majority form distinct nuclear families. Thus, the standard approach of factor analysis cannot be applied to these diet data to ascertain dietary patterns. In this project we propose to investigate whether the determinants of the correlation matrix of each family unit will allow us to adjust the original correlation matrix of the dietary intake data prior to ascertaining dietary intake patterns. If these methods are appropriate, then in the future the dietary patterns among related individuals could be assessed by standard orthogonal principal component factor analysis.^