Markers for the Validation of Reported Dietary Intake in Adults with Cystic Fibrosis

Objective

To identify different markers in order to validate the assessment of dietary intake in adults with cystic fibrosis (CF).

Design

Cross-sectional survey.

Setting

Tertiary care.

Subjects

We assessed 37 adults with CF whose nutritional and respiratory condition was stable and 37 healthy adults, matched for age, sex, and nutritional status.

Interventions

A consecutive, 7-day, prospective dietary survey was given to all the participants. Anthropometric variables were measured and a fasting blood sample was drawn to measure the composition of the serum phospholipid fatty acids by gas chromatography. We also measured fecal fat and nitrogen at 72 hours and 24-hour urine nitrogen.

Results

The ratio of energy intake to basal metabolic rate expenditure was significantly greater in the patients (2.1±0.4) than the controls (1.79±0.4) and the percentage of patients with the ratio of energy intake to basal metabolic rate lower than 1.55 was 24% in the controls (n=9) vs 8% in the patients (n=3). Fecal nitrogen correlated significantly with total energy and the intake of carbohydrates, lipids, and proteins. In the patients, total dietary energy and fat and protein intake correlated positively with fecal fat. The protein and fat intake and fecal nitrogen and fat correlated significantly with urine nitrogen. In the controls, significant correlations were seen between different parameters of intake and the percentage of certain serum phospholipid fatty acids. These correlations in the patients were either absent or less marked.

Conclusions

Use in persons with CF of the energy intake to basal metabolic rate ratio, measurement of fecal fat and nitrogen at 72 hours and of urine nitrogen may be useful to validate dietary surveys. The serum phospholipid fatty acid profile, however, may be less useful for this purpose in these patients.     

Rice Consumption in the United States: Recent Evidence from Food Consumption Surveys

Background

Little is known about rice consumption, related food intake patterns, and the nutritional contribution that rice provides in the diets of Americans.

Objective

To provide information about rice consumption in the United States and the diets of rice consumers.

Design

Data come from the Continuing Survey of Food Intakes by Individuals (1994-1996) and the National Health and Nutrition Examination Survey (2001-2002). Respondents report 24-hour recall dietary intakes. The amount of rice available in foods is estimated using the Food Commodity Intake Database. Consumers are classified based on the amount of rice they consume in foods.

Subjects

The analysis includes information from adult individuals: 9,318 from the Continuing Survey of Food Intakes by Individuals and 4,744 from National Health and Nutrition Examination Survey.

Statistics

Weighted percentages and mean values show the food and nutrient intake amounts. Logistic regression analysis is used to examine relationships among economic, social, and demographic factors that affect rice consumption.

Results

Rice is consumed by a significant portion of the US adult population. Compared with others who did not consume rice, rice consumers consumed a smaller share of energy per day from fat and saturated fat; more iron and potassium; and more dietary fiber, meat, vegetables, and grains. Race/ethnicity and education are determinants of the probability of consuming rice, and more so than low-income status.

Conclusions

Rice consumers choose a diet that includes more vegetables, a smaller share of energy from fat and saturated fat, more dietary fiber and more iron than those who do not consume rice; the differences have remained relatively stable over the last decade. Accounting for race/ethnicity and income levels is important for better understanding of factors that affect food choices and for effective design of dietary interventions.     

Neighborhood Socioeconomic Disadvantage Is Associated with Higher Ratio of 24-Hour Urinary Sodium to Potassium in Young Japanese Women

Information on the relationship of neighborhood characteristics to objective indicators of dietary intake is extremely limited. The aim of this observational cross-sectional study was to examine the association between neighborhood socioeconomic status (SES) and 24-hour urinary excretion of sodium and potassium in a population with a high ratio of urinary sodium to potassium. Subjects were 1,032 female Japanese dietetics students aged 18 to 22 years, residing in 293 municipalities in Japan. Neighborhood SES index was defined by seven municipal-level variables, namely unemployment, household overcrowding, poverty, education, income, home ownership, and vulnerable groups, with an increasing index signifying increasing neighborhood socioeconomic disadvantage. Urinary excretion of sodium and potassium was estimated from a single 24-hour urine sample. Neighborhood SES index was not significantly associated with 24-hour urinary excretion of sodium (mean value for each quartile of neighborhood SES: 133.5, 135.2, 126.5, and 141.7 mmol/day, respectively; P for trend 0.10) or potassium (mean value for each quartile: 43.5, 42.2, 38.4, and 42.5 mmol/day, respectively; P for trend 0.44). However, neighborhood SES index was significantly positively associated with the ratio of 24-hour urinary sodium to potassium (mean value for each quartile: 3.14, 3.28, 3.37, and 3.41, respectively; P for trend 0.03). This significant association remained after adjustment for household SES variables (mean value for each quartile: 3.15, 3.35, 3.29, and 3.41, respectively; P for trend 0.04). Neighborhood socioeconomic disadvantage was associated with higher ratio of 24-hour urinary sodium to potassium in young Japanese women.     

Cohort Study of Molecular Identification and Typing of Mycobacterium abscessus,Mycobacterium massiliense,and Mycobacterium bolletii

Mycobacterium abscessus is the most common cause of rapidly growing mycobacterial chronic lung disease. Recently, two new M. abscessus-related species, M. massiliense and M. bolletii, have been described. Health care-associated outbreaks have recently been investigated by the use of molecular identification and typing tools; however, very little is known about the natural epidemiology and pathogenicity of M. massiliense or M. bolletii outside of outbreak situations. The differentiation of these two species from M. abscessus is difficult and relies on the sequencing of one or more housekeeping genes. We performed extensive molecular identification and typing of 42 clinical isolates of M. abscessus, M. massiliense, and M. bolletii from patients monitored at the NIH between 1999 and 2007. The corresponding clinical data were also examined. Partial sequencing of rpoB, hsp65, and secA led to the unambiguous identification of 26 M. abscessus isolates, 7 M. massiliense isolates, and 2 M. bolletii isolates. The identification results for seven other isolates were ambiguous and warranted further sequencing and an integrated phylogenetic analysis. Strain relatedness was assessed by repetitive-sequence-based PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE), which showed the characteristic clonal groups for each species. Five isolates with ambiguous species identities as M. abscessus-M. massiliense by rpoB, hsp65, and secA sequencing clustered as a distinct group by rep-PCR and PFGE together with the M. massiliense type strain. Overall, the clinical manifestations of disease caused by each species were similar. In summary, a multilocus sequencing approach (not just rpoB partial sequencing) is required for division of M. abscessus and closely related species. Molecular typing complements sequence-based identification and provides information on prevalent clones with possible relevant clinical aspects.Rapidly growing mycobacteria (RGM) are ubiquitous organisms increasingly emerging as important human pathogens. Mycobacterium abscessus is commonly associated with wound infections and abscess formation and is the most frequent RGM causing chronic lung disease, often in immunocompromised patients (15, 22, 24). M. abscessus is also notable for its resistance to treatment and the poor clinical outcome of infection with the organism (22, 24). Within the past decade, two new species of mycobacteria closely related to M. abscessus, M. massiliense and M. bolletii, have been described (1, 3). Information on the pathogenic role of M. massiliense and M. bolletii is still scant. Recent reports have described the isolation of M. massiliense from two patients in the United States (29) and one patient in Italy (35) and, lately, the identification of M. massiliense and M. bolletii among South Korean isolates (18). Both M. massiliense and M. bolletii have also been linked to health care-associated outbreaks (8, 19, 37).The species-level identification of RGM can provide the first indication of antibiotic susceptibility and can suggest the appropriate type of patient management. For example, M. abscessus is more resistant to many antibiotics both in vivo and in vitro than M. fortuitum and M. mucogenicum, but it is usually susceptible to amikacin and clarithromycin (6, 15, 24). M. massiliense was originally reported to be distinguishable from M. abscessus and related species by its susceptibility to doxycycline (3); however, resistant isolates have since been described (19, 37), suggesting that antibiotic susceptibility results may not reliably differentiate among these closely related species.Although 16S rRNA gene sequencing has been used for the identification of nontuberculous mycobacteria (NTM), including RGM, it has limited value in distinguishing among some closely related species (9, 14). Therefore, the use of several other gene targets for the identification of mycobacteria has been proposed (2, 5, 11, 23, 25, 31, 32, 39, 41). Discrimination among M. abscessus, M. massiliense, and M. bolletii (which have identical 16S rRNA gene sequences) has proven to be difficult, with sequencing of different gene targets often providing conflicting results. Among these gene targets, partial sequencing of rpoB has increasingly been used (1, 19, 29, 37).Genotypic analysis of NTM has proven useful not only in the investigation of outbreaks and pseudo-outbreaks (38) but also in characterizing the molecular epidemiology of strains, and in assessing clonal distribution and expansion (4, 7, 13, 17). In particular, molecular typing has recently been used for the characterization of health care-related outbreaks of M. massiliense and M. bolletii (19, 37).We sought to perform a thorough molecular investigation, including strain identification and typing, for a series of 42 clinical isolates (CIs) of M. abscessus, M. massiliense, and M. bolleti from patients monitored in our institution between 1999 and 2007. A retrospective patient chart review assessed demographics, underlying conditions, and clinical history.The 42 CIs and 3 type strains were subjected to multilocus sequence analysis, including sequencing of rpoB, hsp65, secA, and the internally transcribed spacer (ITS) region. The relatedness among the isolates was assessed by use of an automated repetitive-sequence-based PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE). This is the most extensive molecular characterization of non-outbreak-related isolates from patients with M. abscessus, M. massiliense, and M. bolletii infections.     

Serological evidence for long‐term epstein–barr virus reactivation in children living in a holoendemic malaria region of Kenya

To study the long term the effects of chronic exposure to P. falciparum malaria on Epstein–Barr virus (EBV) reactivation in children, EBV‐specific antibody levels were measured in a cross‐sectional survey of two groups of Kenyan children with divergent malaria exposure, varying in age from 1 to 14 years. A total of 169 children were analyzed within three age groups (1–4 years, 5–9 years and 10–14 years). Using a Luminex assay, elevated levels of IgG to EBV lytic and latent antigens were observed in children from the holoendemic malaria area; these remained elevated for each age group studied. In comparison, children from the sporadic malaria area had lower levels of EBV‐specific IgG antibodies and these levels declined across age groups. These data suggest that chronic exposure to malaria may lead to long‐term EBV reactivation. J. Med. Virol. 81:1088–1093, 2009. © 2009 Wiley‐Liss, Inc.     

Analysis of the role of CovR and CovS in the dissemination of Streptococcus pyogenes in invasive skin disease

The global regulatory two-component system CovR/S controls expression of about 15% of the Streptococcus pyogenes (group A streptococcus; GAS) genome. Recently, we found that CovS plays a pivotal role in general stress response of this strictly human pathogen. Therefore, we expected that both CovS and CovR might affect virulence. In this work, mice were inoculated subcutaneously with isogenic nonpolar covR and covS deletion-substitution mutants and the isogenic wild-type strain. The covS mutant behaved like the wild-type parental strain in terms of resulting lesion appearance and invasive disease leading to death. This is in agreement with previous results suggesting that the absence of its cognate sensor kinase does not affect the ability of CovR to become phosphorylated and cause repression of its regulon. However, two different covR deletion-substitution mutants caused significantly less invasive disease and death in the mice than the wild-type parental strain, although the local lesions produced by the covR mutants were more severe and purulent than those resulting from the wild-type GAS strain. Thus, it appears that production of CovR increases the ability of S. pyogenes to cause severe invasive disease in this mouse model and therefore is an important virulence factor for this organism.     

Modeling skin thermal pain sensation: Role of non-Fourier thermal behavior in transduction process of nociceptor

Skin thermal pain is one of the most common phenomena in human daily life (e.g. contact with hot substances) and in clinical thermal therapies (e.g. laser assisted diseased skin ablation), where the thermal behavior in skin tissue is the critical process. However, the underlying physical and neural mechanisms of skin thermal pain are not clearly understood, and there are few attempts to model it. Besides, due to the “lengthy” thermal relaxation time in biological tissue, non-Fourier thermal behavior has been experimentally observed, attracting increasingly attention to this phenomenon. In this paper, a new thermal-neural model was developed in order to investigate the possible role of non-Fourier thermal behavior in the transduction process of skin thermal pain sensation. In the model, the non-Fourier thermal behavior of skin tissue was coupled to the neural response of the nociceptor (special receptor for pain sensation). The results demonstrated that the predicted thermal-neural responses of nociceptors from different bioheat transfer models can deviate substantially under constant surface temperature heating, implying that the non-Fourier thermal feature may play an important role in the nociceptor transduction process of skin thermal pain.     

Boundary detection in carotid ultrasound images using dynamic programming and a directional Haar-like filter

The intima-media thickness (IMT) of the carotid artery, obtained from B-mode ultrasound images, has recently been proposed as one of the most useful indices of atherosclerosis and can also be used to predict major cardiovascular events. Ultrasonic measurements of the IMT are conventionally obtained by time-consuming manual tracing of the interfaces between tissue layers. We propose a computerized method to detect the boundary of the intima-media complex using a directional Haar-like filter that can account for the slope of the boundary in an image. The directional Haar-like filter extracts a directional boundary feature as an image feature in the region of interest, which is used to compute a cost function. A cost function includes not only the directional Haar-like filtering value but also the geometric continuity that is computed for every pixel in the region of interest. The optimal boundary pixels are detected by using a dynamic programming approach that searches for the pixel that minimizes the cost function in each column of the image. We compared the performance of the proposed method with that of manual methods performed by two radiologists. The results showed that our approach produces very similar results to those based on manual tracing, and there was no statistically significant difference between the IMT measurements segmented manually and those analyzed using our method.