Determinants of weekly raw milk use by at-home meal preparers in the USA: evidence from the 2014-2016 American Time Use Survey - Eating and Health Module.

OBJECTIVE: The number of states in the USA that allows sales of raw milk for human consumption has been trending upwards and reached thirty-eight in 2016. These legislative changes could encourage raw milk consumption. The current study examined the determinants of weekly raw milk use by at-home meal preparers in the USA. DESIGN: Using the 2014-2016 American Time Use Survey - Eating and Health Module, multivariate logit regressions and average marginal associations were estimated to examine how at-home meal preparer characteristics, time use and shopping choices, underlying health and the presence of at-risk individuals in households and raw milk legalisation status are associated with the probability an at-home meal preparer consumed or served raw milk during an average week. SETTING: USA. PARTICIPANTS: At-home meal preparers aged 18 years and above. RESULTS: Estimated average marginal associations suggested younger at-home meal preparers, male at-home meal preparers, larger sized households and households located in non-metropolitan areas were more likely to use raw milk during an average week. Married households and households with a person aged 62 years or above were less likely to use raw milk. Variables indicating health characteristics of at-home meal preparers or the presence of an at-risk individual in the household were not statistically significant. CONCLUSIONS: There are many government-sponsored information resources about the risks of raw milk currently available. Additional education may be needed to prevent illnesses from raw milk.

Laparoscopic surgery in middle- and low-income countries: gasless lift laparoscopic surgery.

INTRODUCTION: Surgically treatable conditions are an increasing burden in low- and middle-income countries, and recent studies suggest they have overtaken the "big three" (malaria, tuberculosis and HIV) as a cause of mortality. AIM: In this context, we have worked to modify standard laparoscopic equipment to allow laparoscopy in remote areas without support services such as bottled gases or disposable instruments. RESULTS: A simple and reliable system of gasless laparoscopy has been developed using robust reusable instruments, widening the potential availability of laparoscopic surgery in remote and rural areas. CONCLUSION: Our findings suggest that, using this equipment, appropriately trained surgeons can provide minimally invasive surgery in even the most remote locations.

Prevalence of Vibrio parahaemolyticus, and Vibrio vulnificus in blue crabs (Callinectes sapidus), seawater and sediments of the Maryland Coastal Bays.

AIMS: To determine the prevalence of total and pathogenic Vibrio parahaemolyticus (Vp) and V. vulnificus (Vv) in blue crabs, water and sediment from the Maryland Coastal Bays (MCBs), USA. METHODS AND RESULTS: Crab, haemolymph, sediment and seawater samples were collected monthly from four sites in MCBs from February 2012 through October 2012 with environmental parameters recorded. The most-probable-number (MPN) methodology was used to enumerate Vp and Vv with presumptive colonies and the presence of virulence markers confirmed using polymerase chain reaction (PCR). Results indicate that blue crabs contained both Vp and Vv at densities (7·28 and 5·43 log MPN g(-1) , respectively) higher than those reported for bivalves. In addition, markers for clinically relevant strains of both species were detected in over 30% of samples. Haemolymph, sediment and seawater samples were also routinely positive for both species and clinically relevant strains, but generally at lower densities than found in crabs (4·27, 3·28, and 2·39 log MPN g(-1) per ml(-1) Vp, and 4·28, 2·49 and 2·38 log MPN g(-1) per ml(-1) Vv). CONCLUSIONS: Blue crabs concentrate Vp and Vv at levels greater than found in water or sediment. While changes in abundance associated with temperature are apparent, there is little evidence to support differences among sampling locations. SIGNIFICANCE AND IMPACT OF THE STUDY: These results highlight the potential for blue crab related vibriosis and the importance of proper handling, cooking and care of this popular seafood before consumption.

Modeling and forecasting the distribution of Vibrio vulnificus in Chesapeake Bay.

AIM: To construct statistical models to predict the presence, abundance and potential virulence of Vibrio vulnificus in surface waters of Chesapeake Bay for implementation in ecological forecasting systems. METHODS AND RESULTS: We evaluated and applied previously published qPCR assays to water samples (n = 1636) collected from Chesapeake Bay from 2007-2010 in conjunction with State water quality monitoring programmes. A variety of statistical techniques were used in concert to identify water quality parameters associated with V. vulnificus presence, abundance and virulence markers in the interest of developing strong predictive models for use in regional oceanographic modeling systems. A suite of models are provided to represent the best model fit and alternatives using environmental variables that allow them to be put to immediate use in current ecological forecasting efforts. CONCLUSIONS: Environmental parameters such as temperature, salinity and turbidity are capable of accurately predicting abundance and distribution of V. vulnificus in Chesapeake Bay. Forcing these empirical models with output from ocean modeling systems allows for spatially explicit forecasts for up to 48 h in the future. SIGNIFICANCE AND IMPACT OF THE STUDY: This study uses one of the largest data sets compiled to model Vibrio in an estuary, enhances our understanding of environmental correlates with abundance, distribution and presence of potentially virulent strains and offers a method to forecast these pathogens that may be replicated in other regions.

Aspirin may prevent cholangiocarcinoma: a case-control study from the United kingdom.

BACKGROUND: The proliferation of cholangiocarcinoma cells is suppressed in cell culture by nonsteroidal antiinflammatory drugs (NSAIDs) through the inhibition of cyclo-oxygenase-2 enzyme and also by statins which decrease the production of mediators of the cell cycle. AIMS: To investigate whether there is an inverse association between NSAIDs, including aspirin, and the development of cholangiocarcinoma and, for the first time in a Western population, between statin use and the development of cholangiocarcinoma. METHODS: This epidemiological study had a case-control design in which cases of cholangiocarcinoma diagnosed in Norwich between 2004 and 2010 and in Leicester in 2007 were identified from clinical databases. Controls were patients with basal cell carcinomas treated in the respective dermatology departments. The case notes of all subjects were reviewed to confirm diagnoses and obtain information on medication use. The data were analyzed using unconditional logistic regression to calculate odds ratios (OR) with 95 % confidence intervals (CI). RESULTS: In total, 81 cases of cholangiocarcinoma and 275 controls were identified. For all cases there was radiological evidence of cancer and 86 % of the cases involved the extrahepatic biliary system. Aspirin use was inversely associated with the development of cholangiocarcinoma (OR 0.45, 95 % CI 0.22-0.92), but there were no significant associations between the development of cholangiocarcinoma and NSAIDs (OR 0.39; 95 % CI 0.11-1.42) or statins (OR 0.58; 95 % CI 0.28-1.19). CONCLUSIONS: The epidemiological data from this study support the biological evidence for aspirin having a protective effect against the development of cholangiocarcinoma. Aspirin use should be measured in future etiological studies and assessed as a chemoprevention agent in those at high risk of developing this type of cancer.

A prospective, randomized, single-blind trial of 5-mm versus 3-mm ports for laparoscopic cholecystectomy: is smaller better?

BACKGROUND: Single-incision laparoscopic cholecystectomy (SILC) is said to provide improved cosmesis with a reduction in postoperative pain, but SILC involves a change in operative technique. A single-blind, randomized controlled trial compared cosmetic outcomes and postoperative pain between 3- and 5-mm ports used for laparoscopic cholecystectomy (LC). METHODS: For this study, 80 patients with symptomatic gallstones were recruited from a single center and randomized to a LC using either a 5-mm port and three 3-mm ports (group A) or a 10-mm port and three 5-mm ports (group B). Operative details; pain scores at 1 h, 6 h, and 1 week; and analgesia required during the first week were collected. Cosmetic outcome was assessed at 6 months using a validated questionnaire. RESULTS: For each group, 40 patients were recruited. The two groups were well matched except for sex. Group A had 11 males, and Group B had 4 males. The mean operative time was 49 ± 12 min (range, 24-120 min) in the 3-mm group versus 46 ± 19 min (range, 21-124 min) in the control group (p = 0.40). The two groups did not differ statistically in the day case rate. The pain scores in Group A were 2.5 ± 2.1 at 1 h, 3.2 ± 2.2 at 6 h, and 0.8 ± 2.2 at 1 week versus 4.2 ± 2.9 at 1 h, 3.3 ± 2.4 at 6 h, and 2.1 ± 2.4 at 1 week in Group B (p = 0.003, 0.63, and 0.002, respectively). No difference in the analgesia consumption was observed during the first postoperative week. The patients in Group A had significantly better cosmetic outcome scores at 6 months. CONCLUSION: The use of 3-mm ports is technically feasible in patients undergoing LC for gallstones. The operating times are comparable with those for conventional LC, whereas the pain scores are reduced, and the cosmetic outcome is better.

The gene mutated in bare patches and striated mice encodes a novel 3beta-hydroxysteroid dehydrogenase.

X-linked dominant disorders that are exclusively lethal prenatally in hemizygous males have been described in human and mouse. None of the genes responsible has been isolated in either species. The bare patches (Bpa) and striated (Str) mouse mutations were originally identified in female offspring of X-irradiated males. Subsequently, additional independent alleles were described. We have previously mapped these X-linked dominant, male-lethal mutations to an overlapping region of 600 kb that is homologous to human Xq28 (ref. 4) and identified several candidate genes in this interval. Here we report mutations in one of these genes, Nsdhl, encoding an NAD(P)H steroid dehydrogenase-like protein, in two independent Bpa and three independent Str alleles. Quantitative analysis of sterols from tissues of affected Bpa mice support a role for Nsdhl in cholesterol biosynthesis. Our results demonstrate that Bpa and Str are allelic mutations and identify the first mammalian locus associated with an X-linked dominant, male-lethal phenotype. They also expand the spectrum of phenotypes associated with abnormalities of cholesterol metabolism.

11†Convergence insufficiency: are we making a difference in patients' lives or is it a waste of time!

Convergence insufficiency (CI) is a common condition that can impair visual performance and comfort during close visual work. This prospective study evaluated the effectiveness of interventions on clinical outcomes and quality-of-life using the adult strabismus quality-of-life questionnaire (AS20) in patients with CI.Data was extracted from a database collected at first consultation from 2015 to 2022. Demographics, interventions and outcomes of 84 patients with CI (mean age 47.0±24.9 years) were analysed.Orthoptic exercises were prescribed to 56% of patients, 32% received prisms, 15% received no treatment, with 3 discharged on the same day. At latest follow-up review, 22.6% were recommended to continue exercises, 28.6% had prisms, 1 underwent bimedial resection and 2 had botox. The median follow-up was 5.5(5.0-55)months, 88.1% were discharged with 29.8% following failure to attend and 9.5% deceased. Near-point of convergence (NPC) improved from a median of 15(6-50)cm to 10(6-30)cm. The median AS20 score at presentation were 100(30-100) and 47.5(0-100), and post-intervention were 100(80-100) and 77.5(12.5-97.5) for psychosocial and functional components, respectively.At the latest follow-up, the attendance failure rate was higher for exercises (36%) than for prisms (15%). Improvement was noted in NPC (33%) and mean AS20 scores was 9% higher psychosocially and 32.8% functionally, highlighting the benefits of intervention on patients' quality-of-life.This cohort provides valuable insights into the clinical management of CI, as evidenced by improvements in NPC and AS20 scores. However, the study also found that long-term compliance with treatment is intrinsically challenging, emphasising the importance of disease education.

Can the rat be used as a valid model of human esophageal adenocarcinoma?

Animal models of Barrett's metaplasia and esophageal adenocarcinoma are important to further characterize the disease and test potential therapies. This paper reviews the development of the surgical model of esophageal adenocarcinoma in the rat and considers whether this model provides a biologically accurate representation of Barrett's esophagus and esophageal adenocarcinoma in humans.

Characterization of photochromogenic Mycobacterium spp. from Chesapeake Bay striped bass Morone saxatilis.

A large diversity of Mycobacterium spp. has been isolated from striped bass Morone saxatilis in Chesapeake Bay, USA. The new species M. shottsii and M. pseudoshottsii are the dominant isolates, while the classical fish pathogen M. marinum is found much less frequently. M. fortuitum and M. chelonae, other Mycobacterium spp. known to commonly infect fishes, have not yet been aseptically isolated from striped bass within Chesapeake Bay. While M. pseudoshottsii and M. shottsii have been phenotypically and genotypically characterized, other less common mycobacterial isolates have not. In the present study, we describe 17 photochromogenic isolates from Chesapeake Bay striped bass using phenotypic characterization and multilocus sequencing of 16S rRNA, hsp65 and rpoB genes. Genetic characterization reveals that these isolates are related to widely divergent portions of the mycobacterial phylogeny; however, some interesting trends are observed, such as a majority of isolates (10/17) belonging to the M. simiae-related grouping. Five additional isolates were assigned to the slow-growing mycobacteria (including 2 identified as M. marinum), while 2 are clearly shown to belong genetically to the fast-growing mycobacteria.

Prescribing patterns and outcomes of venous thromboembolism prophylaxis in hospitalized medical and cancer patients: Observations from the Ottawa Hospital.

Guidelines suggest broad use of pharmacologic prophylaxis to prevent venous thromboembolism (VTE) in hospitalized medical patients, however little 'real-world' data exists to support this. Our goal was to describe the use of thromboprophylaxis among general medical and cancer patients admitted to hospital, compare VTE and bleeding outcomes according to use of thromboprophylaxis, and to determine what variables influence prescribing patterns and outcomes. Patients admitted to the general medical and oncology services at The Ottawa Hospital between 2010 and 2015 were retrospectively reviewed and classified according to whether they received initial, delayed, or no pharmacologic thromboprophylaxis during their first hospitalization. Patients with an alternate indication for anticoagulation or those admitted with a bleeding event were excluded from analysis. The primary efficacy outcome was any symptomatic VTE during index hospitalization or within 90 days of discharge, and the primary safety outcome was clinically relevant bleeding during the index hospitalization. 17,262 patients were included in our final analysis. General medical patients selected to receive no, initial, or delayed thromboprophylaxis had 0.4%, 0.7%, and 2.4% rates of VTE; and 0.2%, 0.7%, and 1.5% rates of clinically relevant bleeding complications, respectively. Cancer patients had significantly higher rates of VTE: 3.3%, 3.9%, and 5.0%; and 0.9%, 0.7%, and 3.0% rates of clinically relevant bleeding among those selected to receive no, initial, or delayed thromboprophylaxis, respectively. Overall, our study suggests that broad use of pharmacologic thromboprophylaxis may be unnecessary in select low-risk general medical patients and may be less effective in cancer patients in whom new studies are indicated.

Simulations of wavelength-multiplexed holography for single-shot spatiotemporal characterization of NIF's advanced radiographic capability (ARC) laser.

We simulate the use of a newly developed single-shot wavelength-multiplexed holography-based diagnostic, STRIPED FISH, to fully characterize the as-delivered laser pulses of the National Ignition Facility's Advanced Radiographic Capability (NIF-ARC) laser. To that end, we have performed simulations of the NIF-ARC pulse incorporating (a) a time-integrated spatial-profile measurement and a complete temporal-intensity-and-phase measurement using a frequency resolved optical gating, but without any spatiotemporal pulse characterizations, and (b) simulated first-order spatiotemporal distortions, which could be measured on a single shot if a STRIPED FISH device were deployed.

Human amylin aggregates release within exosomes as a protective mechanism in pancreatic ß cells: Pancreatic ß-hippocampal cell communication.

Pancreatic ß cells are essential in the maintenance of glucose homeostasis during the progression to type 2 Diabetes Mellitus (T2DM), generating compensatory hyperinsulinemia to counteract insulin resistance. It is well known, that throughout the process there is an increased mTORC1 signaling pathway, with an impairment in different quality control systems including ubiquitin-proteasome system and autophagy. In addition, under this situation, pancreatic ß cells start to accumulate amylin protein (IAPP) in aggregates, and this accumulation contributes to the failure of autophagy, damaging different organelles such as plasma membrane, endoplasmic reticulum, mitochondria, and others. Here, we report that IAPP can be incorporated to multivesicular bodies (MVB) and secreted into exosomes, a mechanism responsible for the exportation of these toxic aggregates as vehicles of cell to cell communication. On this regard, we have demonstrated that the exosomes bearing toxic hIAPP released from pancreatic ß cells are capable to induce hyperactivation of mTORC1 signaling, a failure in the autophagic cellular quality control, and favor pro-fission status of the mitochondrial dynamics in hippocampal cells. In summary, our results show that harmful accumulation of hIAPP in pancreatic ß cells may be detoxified by the release of exosomes, which may be captured by endocytosis mechanism damaging neuronal hippocampal cells, which suggest an underlying molecular mechanism to the link between type 2 diabetes and neurodegenerative diseases.

Subunit composition of pre-T cell receptor complexes expressed by primary thymocytes: CD3 delta is physically associated but not functionally required.

Maturation of immature CD4-CD8- (DN) thymocytes to the CD4+CD8+ (DP) stage of development is driven by signals transduced through a pre-T cell receptor (TCR) complex, whose hallmark is a novel subunit termed pre-T alpha (pT alpha). However, the precise role of pre-TCRs in mediating the DN to DP transition remains unclear. Moreover, progress in understanding pre-TCR function has been hampered thus far because previous attempts to demonstrate expression of pT alpha-containing pre-TCRs on the surface of normal thymocytes have been unsuccessful. In this report, we demonstrate for the first time that pT alpha-containing pre-TCR complexes are expressed at low levels on the surface of primary thymocytes and that these pre-TCR complexes comprise a disulfide-linked pT alpha-TCR-beta heterodimer associated not only with CD3-gamma and -epsilon, as previously reported, but also with zeta and delta. Interestingly, while CD3-delta is associated with the pre-TCR complex, it is not required for pre-TCR function, as evidenced by the generation of normal numbers of DP thymocytes in CD3-delta-deficient mice. The fact that any of the signaling components of the pre-TCR are dispensable for pre-TCR function is indeed surprising, given that few pre-TCR complexes are actually expressed on the surface of primary thymocytes in vivo. Thus, pre-TCRs do not require the full array of TCR-associated signaling subunits (gamma, delta, epsilon, and zeta), possibly because pT alpha itself possesses signaling capabilities.

Quantitative PCR assay for Mycobacterium pseudoshottsii and Mycobacterium shottsii and application to environmental samples and fishes from the Chesapeake Bay.

Striped bass (Morone saxatilis) in the Chesapeake Bay are currently experiencing a very high prevalence of mycobacteriosis associated with newly described Mycobacterium species, Mycobacterium pseudoshottsii and M. shottsii. The ecology of these mycobacteria outside the striped bass host is currently unknown. In this work, we developed quantitative real-time PCR assays for M. pseudoshottsii and M. shottsii and applied these assays to DNA extracts from Chesapeake Bay water and sediment samples, as well as to tissues from two dominant prey of striped bass, Atlantic menhaden (Brevoortia tyrannus) and bay anchovy (Anchoa mitchilli). Mycobacterium pseudoshottsii was found to be ubiquitous in water samples from the main stem of the Chesapeake Bay and was also present in water and sediments from the Rappahannock River, Virginia. M. pseudoshottsii was also detected in menhaden and anchovy tissues. In contrast, M. shottsii was not detected in water, sediment, or prey fish tissues. In conjunction with its nonpigmented phenotype, which is frequently found in obligately pathogenic mycobacteria of humans, this pattern of occurrence suggests that M. shottsii may be an obligate pathogen of striped bass.

Predictors of increased PaCO2 during immersed prone exercise at 4.7 ATA.

During diving, arterial Pco(2) (Pa(CO(2))) levels can increase and contribute to psychomotor impairment and unconsciousness. This study was designed to investigate the effects of the hypercapnic ventilatory response (HCVR), exercise, inspired Po(2), and externally applied transrespiratory pressure (P(tr)) on Pa(CO(2)) during immersed prone exercise in subjects breathing oxygen-nitrogen mixes at 4.7 ATA. Twenty-five subjects were studied at rest and during 6 min of exercise while dry and submersed at 1 ATA and during exercise submersed at 4.7 ATA. At 4.7 ATA, subsets of the 25 subjects (9-10 for each condition) exercised as P(tr) was varied between +10, 0, and -10 cmH(2)O; breathing gas Po(2) was 0.7, 1.0, and 1.3 ATA; and inspiratory and expiratory breathing resistances were varied using 14.9-, 11.6-, and 10.2-mm-diameter-aperture disks. During exercise, Pa(CO(2)) (Torr) increased from 31.5 +/- 4.1 (mean +/- SD for all subjects) dry to 34.2 +/- 4.8 (P = 0.02) submersed, to 46.1 +/- 5.9 (P < 0.001) at 4.7 ATA during air breathing and to 49.9 +/- 5.4 (P < 0.001 vs. 1 ATA) during breathing with high external resistance. There was no significant effect of inspired Po(2) or P(tr) on Pa(CO(2)) or minute ventilation (Ve). Ve (l/min) decreased from 89.2 +/- 22.9 dry to 76.3 +/- 20.5 (P = 0.02) submersed, to 61.6 +/- 13.9 (P < 0.001) at 4.7 ATA during air breathing and to 49.2 +/- 7.3 (P < 0.001) during breathing with resistance. We conclude that the major contributors to increased Pa(CO(2)) during exercise at 4.7 ATA are increased depth and external respiratory resistance. HCVR and maximal O(2) consumption were also weakly predictive. The effects of P(tr), inspired Po(2), and O(2) consumption during short-term exercise were not significant.

Toward the improvement of total nitrogen deposition budgets in the United States.

Frameworks for limiting ecosystem exposure to excess nutrients and acidity require accurate and complete deposition budgets of reactive nitrogen (Nr). While much progress has been made in developing total Nr deposition budgets for the U.S., current budgets remain limited by key data and knowledge gaps. Analysis of National Atmospheric Deposition Program Total Deposition (NADP/TDep) data illustrates several aspects of current Nr deposition that motivate additional research. Averaged across the continental U.S., dry deposition contributes slightly more (55%) to total deposition than wet deposition and is the dominant process (>90%) over broad areas of the Southwest and other arid regions of the West. Lack of dry deposition measurements imposes a reliance on models, resulting in a much higher degree of uncertainty relative to wet deposition which is routinely measured. As nitrogen oxide (NOx) emissions continue to decline, reduced forms of inorganic nitrogen (NHx = NH3 + NH4+) now contribute >50% of total Nr deposition over large areas of the U.S. Expanded monitoring and additional process-level research are needed to better understand NHx deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns.

Volume and outcome for major upper GI surgery in England.

BACKGROUND: The correlation between hospital or surgeon volume and outcome for complex surgical procedures has been the subject of several studies in recent years. In the UK, such studies have been used to strengthen the case for centralization of such procedures. The recent availability of easily accessible and fully independent data on hospital outcomes for surgical services in the UK has provided the opportunity to review any potential associations between volume and outcome in the UK. METHODS: Hospital Episode Statistic (HES) data were collected through Dr Foster for four different upper GI procedures (gastrectomy, esophagectomy, pancreaticoduodenectomy, and liver resection) for a 6-year period from 1999 to 2005. Data for each procedure were divided into volume-dependant quartiles to assess any differences in mortality outcome. RESULTS: Generally, mortality rates for all four procedures are lower than previously studies have suggested. A significant trend favoring high volume providers was noted for esophagectomy, with mortality rates varying from 7.8% to 4.0% for lowest to highest volume providers (p < 0.001). A similar but less clear-cut trend was noted for pancreaticoduodenectomy. There was no significant difference for gastric and liver resection between low- and high-volume providers. There was a 20% decrease in centers performing esophagectomy and 28% for centers performing pancreaticoduodenectomy. CONCLUSION: There is a volume outcome association for esophagectomy and pancreaticoduodenectomy. There is no association for gastrectomy or hepatectomy.

Development of a food frequency questionnaire for the assessment of quercetin and naringenin intake.

OBJECTIVES: To measure the relationship between quercetin and naringenin intakes as estimated by food frequency questionnaire (FFQ), and the urinary excretion of quercetin and naringenin aglycones after their enzymatic hydrolysis in human volunteers. SUBJECTS AND METHODS: Volunteers were recruited via the Human Nutrition Unit volunteer databank at the Institute of Food Research, Norwich. Sixty-three volunteers were recruited into the study, of which 14 were excluded and 49 completed the study. A modified FFQ was developed and used to estimate daily intake of quercetin and naringenin in 49 healthy volunteers who also provided five 24-h urine samples over a 2-week period. Urinary excretion of quercetin and naringenin metabolites was determined by solid-phase extraction and high-pressure liquid chromatography. RESULTS: The estimated mean intakes of quercetin and naringenin were 29.4 mg (s.d. 15.0) and 58.1 mg (s.d. 62.7) per day, respectively. Mean urinary excretion of quercetin was 60.1 microg (s.d. 33.1) and that of naringenin was 0.56 mg (s.d. 0.4). The correlation between FFQ estimated intake of quercetin and naringenin and levels excreted in the urine were r=0.82 (P<0.0001) and r=0.25 (P=0.05), respectively. CONCLUSIONS: We observed a statistically significant correlation between the urinary excretion of quercetin and naringenin metabolites and their dietary intake as estimated by FFQ. Use of FFQs in epidemiological studies requiring an estimate of flavonoid intake seems justified.