Impact of Dietary Factors and Inflammation on Cognition among Older Adults.

OBJECTIVE: This study examined the influence of age, nutrition (as measured through food diaries and serum/plasma biomarkers) and inflammatory markers on cognitive performance in adults 60 years of age and older. DESIGN: A cross-sectional population based study, data from the National Health and Nutrition Examination Survey (NHANES; 2001-2002 wave). PARTICIPANTS: This study included 1,048 adults who had valid dietary data, blood biomarkers, were 60 years or older, completed the cognitive test, and had complete demographic information. METHOD: A series of regression models were used to examine the relationship between cognitive function as measured by the Digit Symbol Substitution Task (DSST), dietary factors/biomarkers and inflammation. Mediation analyses were then utilized to examine whether individual nutrients accounted for the relationships between age and DSST performance. RESULTS: Dietary fat intake, serum vitamin E, serum folate, serum iron, plasma homocysteine, and serum vitamin D were significantly associated with better DSST performance. Elevated fibrinogen and C-reactive protein, were significantly associated with poorer cognitive function, but did not remain statistically significant after controlling for age, gender, education, ethnicity, income, and total calorie intake. Serum vitamin D and plasma homocysteine accounted for a portion of age-related variance in DSST. Specifically, higher levels of vitamin D were related to better DSST performance, while higher homocysteine resulted in poorer cognitive performance. CONCLUSION: Diet and nutrition are important modifiable factors that can influence health outcomes and may be beneficial to remediate age-related declines in cognition. Adequate nutrition may provide a primary preventive approach to healthy aging and maintenance of cognitive functioning in older adults.

Parasitic scabies mites and associated bacteria joining forces against host complement defence.

Scabies is a ubiquitous and contagious skin disease caused by the parasitic mite Sarcoptes scabiei Epidemiological studies have identified scabies as a causative agent for secondary skin infections caused by Staphylococcus aureus and Streptococcus pyogenes. This is an important notion, as such bacterial infections can lead to serious downstream life-threatening complications. As the complement system is the first line of host defence that confronts invading pathogens, both the mite and bacteria produce a large array of molecules that inhibit the complement cascades. It is hypothesised that scabies mite complement inhibitors may play an important role in providing a favourable micro-environment for the establishment of secondary bacterial infections. This review aims to bring together the current literature on complement inhibition by scabies mites and bacteria associated with scabies and to discuss the proposed molecular link between scabies and bacterial co-infections.

Guidelines for the validation of qualitative multi-residue methods used to detect pesticides in food.

There is a current trend for many laboratories to develop and use qualitative gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) based multi-residue methods (MRMs) in order to greatly increase the number of pesticides that they can target. Before these qualitative MRMs can be used for the monitoring of pesticide residues in food, their fitness-for-purpose needs to be established by initial method validation. This paper sets out to assess the performances of two such qualitative MRMs against a set of parameters and criteria that might be suitable for their effective validation. As expected, the ease of detection was often dependent on the particular pesticide/commodity combinations that were targeted, especially at the lowest concentrations tested (0.01 mg/kg). The two examples also clearly demonstrated that the percentage of pesticides detected was dependent on many factors, but particularly on the capabilities of the automated software/library packages and the parameters and threshold settings selected for operation. Another very important consideration was the condition of chromatographic system and detector at the time of analysis. If the system was relatively clean, then the detection rate was much higher than if it had become contaminated over time from previous injections of sample extracts. The parameters and criteria suggested for method validation of qualitative MRMs are aimed at achieving a 95% confidence level of pesticide detection. However, the presence of any pesticide that is 'detected' will need subsequent analysis for quantification and, depending on the qualitative method used, further evidence of identity.

Contractile, but not endothelial, dysfunction in early inflammatory arthritis: a possible role for matrix metalloproteinase-9.

BACKGROUND AND PURPOSE: Excess morbidity/mortality in rheumatoid arthritis (RA) is associated with increased incidence of cardiovascular disease. In this 'proof-of-concept' study, vascular function was characterized in the murine collagen-induced arthritis (mCIA) model, the benchmark choice for evaluation of the pathological processes and assessment of new therapies. EXPERIMENTAL APPROACH: Mice in the very early stages of arthritis development [and appropriate naïve (non-immunized) age-matched controls] were used in the study. Blood pressure was measured using tail cuff plethysmography. Vascular function in rings of isolated aorta was studied with isometric tension myography. Levels of NO metabolites (NO(x)), MMP-9 protein and IL-1ß in plasma and MMP-9 protein in aortic homogenates were quantified. KEY RESULTS: Impaired vascular contractile responses in arthritis were unaffected by ex vivo inhibition of NOS (endothelial/neuronal and inducible) or COX activities. Endothelium-dependent and -independent relaxation, plasma NO(x) and blood pressure were unaffected by arthritis. Plasma and aortic homogenate MMP-9 protein levels were increased significantly in arthritis. Incubation of aortic tissues from naïve control animals with exogenous MMP-9 impaired subsequent contractile responses, mirroring that observed in arthritis. A role for IL-1ß in perpetuating contractile dysfunction and increasing aortic MMP-9 was excluded. CONCLUSIONS AND IMPLICATIONS: These data identify for the first time a relationship between early arthritis and contractile dysfunction and a possible role for MMP-9 therein, in the absence of overt endothelial dysfunction or increased NO production. As such, MMP-9 may constitute a significant target for early intervention in RA patients with a view to decreasing risk of cardiovascular disease.

Investigation into the validity of extrapolation in setting maximum residue levels for pesticides in crops of similar morphology.

Field trials were initiated to investigate if extrapolation procedures, which were adopted to limit costs of pesticide registration for minor crops, are valid. Three pairs of crops of similar morphology; carrots/swedes, cauliflower/calabrese (broccoli) and French beans/edible-podded peas; were grown in parallel at four different geographical locations within the UK. The crops were treated with both systemic and non-systemic pesticides under maximum registered use conditions, i.e. the maximum permitted application rates and the minimum harvest intervals. Once mature, the crops were harvested and analysed for residues of the applied pesticides. The limits of quantification were in the range 0.005-0.02 mg kg(-1). Analysis of variance and bootstrap estimates showed that in general, the mean residue concentrations for the individual pesticides were significantly different between crop pairs grown on each site. Similarly, the mean residue concentrations of most of the pesticides in each crop across sites were significantly different. These findings demonstrate that the extrapolations of residue levels for most of the selected pesticide/crop combinations investigated; chlorfenvinphos and iprodione from carrots to swedes; carbendazim, chlorpyrifos, diflubenzuron and dimethoate from cauliflower to calabrese; and malathion, metalaxyl and pirimicarb from French beans to edible-podded peas; appear invalid.

Occurrence and risks associated with chlormequat residues in a range of foodstuffs in the UK.

Trends in the usage pattern of chlormequat (a plant growth regulator) on cereal crops in the UK over the past 6 years are presented. The figures have been supplemented by monitoring of chlormequat residues in food commodities through the UK surveillance programme, and for cereals, the carry-through into a number of processed cereal-based foods has been followed. A downward trend of chlormequat residue levels in pears sampled between 1997 and 2002 was observed. This decline reflects changes that were introduced in European and national regulations and which have proven to be extremely effective in reducing both the frequency of detection and levels of chlormequat residues. Both acute and chronic risk assessments were undertaken based on aggregate dietary exposure data. Even when the highest residues observed were used in the calculations, the assessments showed that both the short- and long-term intakes for all consumer groups would be unlikely to cause adverse health effects and were therefore not of any cause for concern.

Guardianship primavera: a first look at factors associated with having a legal guardian using a nationally representative sample of community-dwelling adults.

Although guardianship is an intrusive intervention that usually removes an adult's basic civil rights, studies of factors that place adults at risk for guardianship have largely been based on small studies of court files. While important and informative, these studies do not allow us to draw anything but tentative conclusions on risk factors for guardianship. The purpose of this article is to examine risk factors for having a legal guardian using a nationally representative sample for the first time. Logistic regression was conducted on the probability of having a legal guardian, using the Andersen model of health care utilization adapted for factors implied by the guardianship literature. The National Health Interview Supplement on Disability (1995) sample consisted of 65,013 adults aged 19 and older, and a sub-sample aged 60 and older (n = 13,784). Results indicate, first, that the prevalence of guardianship in community-dwelling adults is 0.3 percent, or over 750,000 people. Second, particularly for older adults, increasing age, having physical or emotional limitations, a small family network, and not living with a spouse are associated with having a guardian. Decreasing size of family networks and increasing marital disruption in future cohorts of older adults may suggest increasing need for legal guardianship. Further study should be conducted to replicate these findings in other large data sets and in extensive community studies.

Assessment of the stability of pesticides during cryogenic sample processing. 1. Apples.

An assessment of the stability of a large number (106) of pesticides and related compounds during the cryogenic sample processing of apples has been undertaken. For the first time the procedure included an assessment of the losses during the freezing of the fruits, prior to processing. The stability of each pesticide during processing was assessed by comparing the mean recovery for the laboratory-spiked samples with the mean "survival" of the pesticides in cryogenically processed samples. The results clearly demonstrate that the vast majority, 94 of 106, of pesticides were stable during cryogenic processing. Of particular importance was that losses of several pesticides [bitertanol (95%), heptenophos (50%), isofephos (40%), and tolylfluanid (48%)] reported to occur during ambient processing of apples did not occur during cryogenic processing. Losses of dichlofluanid (54%), chlozolinate (22%), and etridiazole (40%), previously reported to occur during ambient processing of apples, were reduced to barely significant levels (10, 17, and 14%, respectively) by cryogenic processing. Small apparent losses for a few of the compounds were attributable to analytical and sample handling difficulties, rather than to losses during processing, and need further investigation.

Taxon-specific oligonucleotide primers for detection of two ancient endomycorrhizal fungi, Glomus occultum and Glomus brasilianum.

A unique oligonucleotide pair, GOCC56:GOCC427, was designed that correctly primed specific amplification of a approximately 370-bp sequence spanning the ITS and 5.8S rDNA regions of Glomus occultum and Glomus brasilianum. In addition, this primer pair successfully detected G. occultum and G. brasilianum DNA in nested PCR using a primary PCR product amplified from highly diluted extracts of colonized corn (Zea mays) roots using modified ITS1:ITS4 primers. A second primer pair, GBRAS86:GBRAS388, primed specific amplification of a approximately 200-bp sequence spanning the ITS and 5.8S rDNA regions present only in G. brasilianum and Glomus strain GR582. Combined use of both primer pairs provides the means to detect and differentiate two ancient endomycorrhizal species, G. occultum and G. brasilianum, undetectable by standard root staining procedures. Sequence analysis showed that the purported G. occultum strain GR582 is likely a strain of G. brasilianum.

Examining the direct costs and effectiveness of syphilis detection by selective screening and partner notification.

Selective screening and partner notification are two principal means of preventing and controlling syphilis in the United States, yet few studies have been undertaken to compare and evaluate the cost or effectiveness of detecting syphilis using either strategy. The objective of this paper is to assess from the perspective of a health department the cost-effectiveness of selective screening compared with the strategy of partner notification in the detection of early syphilis in Houston, Texas, in 1994 and 1995. The cost-effectiveness analysis was performed using the recurring direct costs associated with detecting syphilis by both strategies. The middle estimates for the total direct costs associated with selective screening and partner notification were $579,101 and $229,529, respectively, for the 1466 and the 567 cases of early syphilis detected. On a cost per case basis, selective screening was more cost-effective than partner notification in the detection of primary, secondary and maternal syphilis cases. However, when consideration was given to prophylactic treatment, partner notification was more cost-effective in the detection of all early stage disease. Our findings suggest that the relative benefit of partner notification over selective screening depends on prophylactic treatment and an increase in worker productivity.

Trends in health and ability to work among the older working-age population.

OBJECTIVES: Because of recent changes in Social Security regulations that will soon begin to raise the age of eligibility for full retirement benefits, it is important to determine whether health and ability to work at older ages have improved in recent years. METHODS: Individual-level data from the National Health Interview Survey from 1982 through 1993 are used in this analysis. Trends in self-reported ability to work, presence of disease, and causes of actual work limitation are examined. RESULTS: Men and women in their 60s, that is those in the older working ages and younger retirement ages, report significant improvement in their ability to work. The change in work ability is large enough so the percentage unable to work at age 67 in 1993 is lower than the percentage unable to work at age 65 in 1982. This improvement appears to have been similar for racial and ethnic groups and across educational subgroups of the population, although African Americans and those with lower educational attainment are less healthy to begin with. The improvement in health is due to the changing educational composition of the population, which is linked to better life-long health, different occupational circumstances, and better health behaviors. In addition, the improvement in work ability is explained by decline in the prevalence of cerebro/cardiovascular diseases and arthritis. DISCUSSION: The level of observed improvement in work ability means that the legislated rise in age of full eligibility for Social Security benefits should be more than compensated for by the improved ability to work.

Correlates of open- and locked-facility placement in a population of decisionally impaired adults.

OBJECTIVES: This study compares characteristics of public conservatees placed in locked facilities with those in less restrictive settings. Given the principle of the least restrictive alternative, the study seeks to identify factors, including the role of aging and advanced age, associated with restrictive placement within conservatorship. METHODS: Management Information Systems data on 1,534 adult conservatees in Los Angeles County in July, 1993, are examined in cross-section. Models exploring individual and environmental characteristics of conservatees and linear, curvilinear, and multiplicative aging effects are tested on the probability that adults are placed in locked facilities versus all other placement types. RESULTS: Locked facility placement is associated with being female, receiving SSI, a diagnosis of dementia, and being identified as a danger to oneself and to others. Locked-facility placement is associated with increasing age until age 60, when the effect becomes inversely related; the multiplicative effect of older age and impaired functioning is also inversely related. DISCUSSION: The curvilinear nature of age and the interaction effect of Age x Functioning implies that increasing frailty in older adults makes locked facility-placement less likely. Further research is needed on whether alternative placement types, such as special care units with secured perimeters, can further reduce the need for locked facilities.

Guidelines for in-house validation of analytical methods for pesticide residues in food and animal feeds.

Criteria are presented by which analytical methods may be judged to have been validated for the determination of pesticide residues. All stages of analysis are addressed, from initial preparation of samples to the production of results, but with a focus on simplicity and cost-effectiveness of the requirements. Criteria are provided for both quantitative and qualitative (screening) methods and they may be applied to single- or multi-residue methods.

Does the use of ultrasonography improve the outcome of children with appendicitis?

OBJECTIVE: To determine whether the use of ultrasonography (US) improves the outcome of children with appendicitis. METHODS: All cases of patients (<17 years old) with pathologically confirmed appendicitis treated in the ED between July 1992 and December 1995 were retrospectively reviewed. RESULTS: 231 charts met criteria for analysis. 100 (43%) patients had US prior to surgery. Age, race, and insurance status were similar for children in the US and non-US groups; there were no differences between the groups at presentation in mean temperature, mean WBC count, or percentage of children with vomiting, diarrhea, abdominal tenderness, or guarding. Those in the non-US group were more often male (71%, p=0.002) and more frequently had right lower quadrant pain (65%, p=0.003). Time from ED triage to the OR was 17.1 hours (US group) vs 10.4 hours (non-US group) (p=0.002). The perforation rates and the complication (abscess, wound infection, wound dehiscence) rates were similar for children in the two groups. Hospital charges were higher in the US group than in the non-US group ($14,123 vs $13,021, p=0.007). CONCLUSION: The use of US did not result in early diagnosis of appendicitis, nor was it associated with a reduction in perforation or complication rates. Among children with clinical evidence of appendicitis, US was associated with a delay in surgery and an increase in hospital charges.

Cohort differences in disability and disease presence.

Using the National Health Interview Surveys conducted from 1982 through 1993, this article examines cohort patterns in disability and disease presence for adults born between 1915 and 1959, at ages ranging from 30 to 69 years. In general, disability decreases for cohorts born between 1916 and the early 1940s (for men) or the early 1950s (for women), but begins to increase for cohorts born after those dates. Later-born cohorts have significantly lower levels of some diseases, most importantly cardiovascular diseases, arthritis, and emphysema. However, some diseases and conditions are more prevalent in later-born cohorts: asthma, musculoskeletal disorders, and orthopedic impairments. The results presented here indicate that adults born in the late 1940s and 1950s will be in better cardiovascular health but may be in worse musculoskeletal condition when they enter old age compared with current cohorts of older persons.

The carry-through of residues of maleic hydrazide from treated potatoes, following manufacture into potato crisps and 'jacket' potato crisps.

Potatoes, which had been treated 'in the field' with a commercial formulation of maleic hydrazide, were processed into potato crisps and jacket potato crisps on a factory production line using standard manufacturing conditions. Samples were taken at strategic points throughout the process and analysed to determine the degree of carry-through of residues. Results demonstrated that ca 56% of the maleic hydrazide residue in a potato could be carried through into the potato crisps, irrespective of which type of crisp was being manufactured. Results from a similarly constructed study investigating the fate of pesticides applied post-harvest showed that carry-through was less than 10%. This difference is explained in terms of the different modes of action of the two classes of pesticides being investigated. It is known that, as maleic hydrazide is a systemic pesticide, it will be located within the flesh of the potato tuber and is therefore likely to be protected from the various stages of the crisping process. However, the post-harvest non-systemic pesticides are applied to the exterior surface of the tuber and are therefore not likely to be protected in the same way. The results also showed that, due to the concentration effect caused by the loss of moisture during crisp manufacture, the levels of maleic hydrazide residues in crisps (on a mg/kg product basis) were approximately twice those measured in the original potatoes.

The analysis of cyhexatin residues in apples, pears and kiwi fruit using inductively coupled plasma mass spectrometry as an initial screen for total tin, with confirmation by gas chromatography-mass spectrometry.

Inductively coupled plasma-mass spectrometry (ICP-MS) has been used to determine concentrations of total tin in samples of apples, pears and kiwi fruit, following acid digestion. It was found that the background levels of tin in these fruits were normally below 0.06 mg/kg, which was equivalent to the target reporting limit for cyhexatin for this work of 0.2 mg/kg. The procedure was used to screen a total of 72 retail samples. Three apple samples contained tin at concentrations greater than 0.06 mg/kg. These three samples were re-analysed by a second confirmatory method using gas chromatography-mass spectrometry (GC-MS) as the determinative step. Results obtained by this method demonstrated that in fact, none of the samples contained cyhexatin residues at or above a reporting limit of 0.1 mg/kg. The use of ICP-MS as a preliminary screen substantially reduced the number of samples requiring analysis by GC-MS, thus reducing the cost of the survey (in terms of staff hours) by approximately 30%. The screening method could potentially be applied to other organometallic pesticide residues.

Criteria for placing older adults in public conservatorship: age as proxy for need.

This study was conducted on a sample of 589 adult public conservatees in Los Angeles County, California, to determine whether the process used to assign them into conservatorship is age-blind, as California law suggests. Findings indicate that age is not associated with the amount of time spent evaluating adults for conservatorship but that increasing age, rather than need, is associated with assignment into Probate conservatorship. The association of age with Probate conservatorship appears to result from the vagueness of the criteria for Probate conservatorship-unable to manage-resulting in the use of age as a proxy for need in the case of decisionally impaired older adults.

Further evidence on recent trends in the prevalence and incidence of disability among older Americans from two sources: the LSOA and the NHIS.

The Longitudinal Study on Aging (LSOA) and the National Health Interview Survey (NHIS) are used to examine change in the prevalence of disability from 1982 through 1993 for persons 70 years of age and over. Changes in the likelihood of becoming disabled and the likelihood of recovering from disability also are investigated with the LSOA. There is some evidence for improving disability status among the old. The prevalence of disability is somewhat lower in more recent years in the NHIS; also, the incidence of disability is lower, and the rate of recovery higher during 1988-90 than in the 1984-86 interval. On the other hand, the prevalence of disability increases at some dates after 1984 in the LSOA sample. In both datasets, there is fluctuation rather than a clear trend in the prevalence of disability. Continued steady improvement in rates of onset and recovery and a consistent trend toward improving prevalence is needed before concluding that we are witnessing the beginning of an ongoing trend toward improving health among the older population.

Determination of the pesticide fenbutatin oxide in tomatoes, cucumbers and bananas by high performance liquid chromatographic/atmospheric pressure chemical ionization-mass spectrometry.

A rapid method, using high-performance liquid chromatography (HPLC)/ atmospheric pressure chemical ionization-mass spectrometry, has been developed for the determination of fenbutatin oxide in tomatoes, cucumbers and bananas. Samples were homogenized with sodium carbonate and ethyl acetate, filtered through sodium sulphate, concentrated and solvent exchanged into acetonitrile prior to analysis. HPLC was performed on a Hypercarb column with 10:90 acetic acid (5% v/v glacial acetic acid in water)/acetonitrile at a flow rate of 1 mL/min. Positive ionization selected-ion monitoring was performed on the 7 isotopic cluster ions from the tris(2-methyl-2-phenylpropyl) tin fragment. A comparison of solvent-based and extract-based standards showed that tomato and cucumber matrices had a slight enhancement effect on the signal intensity, whereas the banana matrix exerted a signal suppression effect. Calibration was linear over the range 0.25-5.0 ng/microL. The mean spike recoveries (extracts spiked at 0.5 mg/kg) were 88% for tomatoes and 80% for both cucumbers and bananas with relative standard deviations of 6%, 7% and 8% respectively. Limits of detection were commodity dependent and ranged from 0.06-0.12 ng/microL (equivalent to 0.01-0.02 mg/kg in the crop). Ionization was stable for long analytical time periods.