The inner membrane protein YhiM is necessary for Escherichia coli growth at high temperatures and low osmolarity.

To survive, Escherichia coli must be able to survive in rapidly changing environmental conditions including changes in temperature and osmolarity. We have studied the role of the inner membrane protein YhiM in changing environmental conditions. Our data indicate that YhiM is required for normal growth at 37 and 41 °C but not 21 °C. YhiM-deficient cells grown at high temperatures spend more time in lag phase and stop growing at lower cell densities in comparison with their wild-type counterparts. They also have growth defects in low NaCl medium at 37 °C and do not grow at all at 41 °C. The effects of low NaCl can be rescued by addition of KCl or sucrose to the low salt medium. Finally, YhiM-deficient cells fail to grow in dilute medium at 41 °C. These data suggest that YhiM may be important in protecting the cells from changes in temperature and osmolarity.

Raloxifene, soy phytoestrogens and endothelial function in postmenopausal women.

OBJECTIVE: To compare the effects of raloxifene and soy phytoestrogens on endothelial function in healthy, postmenopausal women. DESIGN: Randomized, double-blind, placebo-controlled, cross-over trial. Subjects (n = 22; mean age 58.5 years) underwent endothelial function testing at baseline and following 6 weeks of daily raloxifene 60 mg, soy phytoestrogens 55 mg, and placebo in random sequence with intervening 6-week wash-out periods. Endothelial function was assessed as flow-mediated vasodilatation (FMD) of the brachial artery using high-resolution ultrasound; digital flux was measured with laser Doppler velocimetry. RESULTS: Baseline (pretreatment) FMD was almost within normal range at 9.6% (+/-6.4). FMD did not change from baseline within any treatment group, and no between-group differences were detected. FMD values following treatment with raloxifene, soy, and placebo were 10.3% (+/-12.3), 8.3% (+/-7.7), and 9.5% (+/-4.4), respectively. Area under curve ratios showed no treatment differences for digital velocimetry. CONCLUSIONS: In this study, neither raloxifene nor soy enhanced endothelial function in postmenopausal women. However, the cohort had relatively normal endothelial function at baseline. Further study is required to determine if particular subgroups of postmenopausal women derive vascular benefit from the use of selective estrogen receptor modulators or soy phytoestrogens.

Men with cancer: is their use of complementary and alternative medicine a response to needs unmet by conventional care?

This qualitative study aims to investigate why men with cancer choose to use complementary and alternative medicine (CAM), and whether CAM is used to fill 'gaps' in conventional cancer care or as an 'alternative' to conventional treatment. Interviews were carried out with 34 CAM users recruited from a National Health Service (NHS) oncology department, an NHS homeopathic hospital and a private cancer charity offering CAM. Participants used therapies to improve quality of life, to actively 'fight' the disease and possibly prolong life, but rarely as an alternative to conventional treatment. Many were initially sceptical about CAM, but took a 'pragmatic' and 'consumerist' approach to getting their needs met. Gaps in conventional care included: lack of empathy and support during and after treatment, poor continuity of care, and lack of advice on self-help, diet and lifestyle. The skills of CAM therapists may enable them to tap into the underlying needs of men in a way that health professionals do not always have the time or the skills to achieve.

Annexinopathies.

Annexins comprise a conserved family of proteins characterised by their ability to bind and order charged phospholipids in membranes, often in response to elevated intracellular calcium. The family members (there are at least 12 in humans) have become specialised over evolutionary time and are involved in a diverse range of cellular functions both inside the cell and extracellularly Although a mutation in an annexin has never been categorically proven to be the cause of a disease state, they have been implicated in pathologies as diverse as autoimmunity, infection, heart disease, diabetes and cancer. 'Annexinopathies' were first described by Jacob H. Rand to describe the pathological sequelae in two disease states, the overexpression of annexin 2 in a patients with a haemorrhagic form of acute promyelocytic leukaemia, and the under-expression of annexin 5 on placental trophoblasts in the antiphospholipid syndrome. In this chapter we will outline some of the more recent observations in regard to these conditions, and describe the involvement of annexins in some other major causes of human morbidity.

Disorder-to-order transition of 1,4-dimethylnaphthalene: Formation of molecular complex with water and p-xylene on Al2O3 (0001).

Amorphous 1,4-dimethylnaphthalene, DMN, that can be prepared by vacuum deposition on Al2O3 exhibits relatively intense excimer fluorescence. Upon heating the surface, the adlayer undergoes a disorder-to-order transition, signaled by a decrease in excimer and an increase in monomer fluorescence. In a bilayer experiment, water, which has a lower desorption temperature than DMN, is vacuum deposited first, followed by DMN. When the surface is heated, water percolates through the DMN and forms a molecular H2O-DMN surface complex that desorbs simultaneously. The stoichiometric ratio of this complex was determined to be (DMN)(1.4+/-0.3).H2O. When the bilayer was formed with p-xylene, a complex of DMN-p-xylene was observed that had the stoichiometry of (DMN)(7.9+/-1).p-xylene.

Molecular and quantitative genetic divergence among populations of house mice with known evolutionary histories.

Evolutionary biologists have long been interested in the processes influencing population differentiation, but separating the effects of neutral and adaptive evolution has been an obstacle for studies of population subdivision. A recently developed method allows tests of whether disruptive (ie, spatially variable) or stabilizing (ie, spatially uniform) selection is influencing phenotypic differentiation among subpopulations. This method, referred to as the F(ST) vs Q(ST) comparison, separates the total additive genetic variance into within- and among-population components and evaluates this level of differentiation against a neutral hypothesis. Thus, levels of neutral molecular (F(ST)) and quantitative genetic (Q(ST)) divergence are compared to evaluate the effects of selection and genetic drift on phenotypic differentiation. Although the utility of such comparisons appears great, its accuracy has not yet been evaluated in populations with known evolutionary histories. In this study, F(ST) vs Q(ST) comparisons were evaluated using laboratory populations of house mice with known evolutionary histories. In this model system, the F(ST) vs Q(ST) comparisons between the selection groups should reveal quantitative trait differentiation consistent with disruptive selection, while the F(ST) vs Q(ST) comparisons among lines within the selection groups should suggest quantitative trait differentiation in agreement with drift. We find that F(ST) vs Q(ST) comparisons generally produce the correct evolutionary inference at each level in the population hierarchy. Additionally, we demonstrate that when strong selection is applied between populations Q(ST) increases relative to Q(ST) among populations diverging by drift. Finally, we show that the statistical properties of Q(ST), a variance component ratio, need further investigation.

Effects of storage time and thawing methods on the recovery of Mycoplasma species in milk samples from cows with intramammary infections.

This study was executed to determine the effects of storage and thawing on the viability of Mycoplasma spp. in milk from cows with intramammary infections. The trial was designed using a control sample and seven handling regimens subjected to two methods of thawing. There was a significant treatment effect on the recovery of colony-forming units in milk samples when comparing the control sample with handling regimens 1 through 7. There was a continuous decline in log (10) mean number of cfu/mL recovered. Mean concentrations were 6.29, 4.64, 3.69, 3.01, 1.86, 4.41, 4.13, and 3.18 for control and handling regimens 1 to 7, respectively. To determine the best thawing method, handling regimen 1 through 7 samples were thawed using two methods. On average, more mycoplasma were recovered from milk samples thawed at ambient temperature (4.04 cfu/mL) than milk samples thawed in a 37 degrees C water bath (3.76 cfu/mL). A final comparison was made between individual treatments. With the exception of the handling regimen 5 to 6 pair-wise comparison, all pair-wise comparisons between handling regimens were significantly different. The results of this study indicate that storage and thawing of milk samples is harmful to mycoplasma organisms. Fresh samples should be used to improve detection of Mycoplasma spp. from milk of infected cattle. If frozen samples are used, then length of storage time should be minimized, and thawing milk at ambient temperature will improve recovery of mycoplasma as opposed to thawing in a 37 degrees C water bath.

Real-time diode laser measurements of vapor-phase benzene.

An absorption spectrometer equipped with a IV-VI semiconductor tunable mid-IR diode laser was used to make sensitive measurements of benzene (C(6)H(6)) gas in the 5.1-microm spectral range. Wavelength modulation coupled with second-harmonic detection achieved accurate real-time quantification of benzene concentrations down to a minimum detection limit of 1 ppmv with an integration time of 4 s. A variety of calibrated benzene-sensing measurements were made, including the determination of the benzene concentrations in vehicle exhaust and headspace vapors from unleaded gasoline and other liquids. Kinetic phenomena, including the monitoring of benzene evaporation and absorption/desorption by granulated activated carbon were observed with the instrument. Measurements were performed that allowed experimental determination of the activation energy for desorption of benzene from activated carbon, which was found to be 198 meV/molecule (19.0 kJ/mol).

Increased competition may promote species coexistence.

It is a mainstay of community ecology that local exclusion of species will result if competitive pressures become too large. The pattern of exclusion may be complicated, but the qualitative orthodoxy has changed little since the pioneering work of Lotka, Volterra, and Gause--no two species can occupy the same niche. Stated in a more precise form, the higher the intensity of interspecific competition in an assemblage of species, the fewer the number of species that can coexist in perpetuity. We suggest that this orthodoxy results from "linear" thinking, and that if the classical equations are formulated more realistically with attendant nonlinearities, the orthodoxy breaks down and higher levels of competition may actually increase the likelihood that species will avoid competitive exclusion. Furthermore, this increased probability of coexistence at higher levels of competition is accompanied by characteristic dynamic patterns: (i) at lower levels of competition, after all extinction events have occurred, remaining species follow irregular chaotic patterns; (ii) at higher levels of competition, when most species coexist, all species are entrained in a single large limit cycle; (iii) the transient behavior appears to correspond to a special case of chaos, uniform phase chaotic amplitude.

Effective Population Size during Grass Germplasm Seed Regeneration.

Effective population size (N(e)) is the key parameter for predicting genetic drift associated with germplasm regeneration. A major factor reducing N(e) below the census population size (N(c)) is variation in seed production among plants in a given population. The objectives of this study were to estimate N(e)/N(c) associated with variation in seed production in three model wind pollinated, perennial grass species [Lolium perenne L., Festuca pratensis Huds., and Pseudoroegneria spicata (Pursh) Á. Löve] and to recommend cost effective sampling methodology to maximize N(e)/N(c) during seed regeneration. Three accessions of each species were grown at two field locations and variation in seed number among plants and mean seed production per plant used to estimate N(e)/N(c). Mean seeds per whole plant, standard deviations, and N(e)/N(c) differed among species, and accessions within species (P < 0.05). For whole plant samples, average N(e)/N(c) for each species differed with values of 0.42, 0.51, and 0.63 for L. perenne, F. pratensis, and P. spicata, respectively. However, average N(e)/N(c) based on two inflorescences per plant was 0.69, 0.88, and 0.86 for L. perenne, F. pratensis, and P. spicata, respectively, which was higher than that of whole plant samples. This higher N(e)/N(c) resulted from the elimination of the variation in inflorescence number per plant, a major source of variation in seed number among plants. The results showed the high potential for genetic drift in small regeneration populations. Increased plant populations and harvesting a constant number of inflorescences per plant are recommended as cost-effective methods to minimize genetic drift during regeneration of outcrossing grass germplasm.

Fatalities caused by the MDMA-related drug paramethoxyamphetamine (PMA).

The past several years have seen a marked increase in the recreational use of 3,4-methylenedioxymethamphetamine (MDMA) or "Ecstasy". MDMA use is especially common among young people participating in dance parties called "raves". Paramethoxyamphetamine (PMA) exhibits both structural and pharmacological similarity to MDMA. It may, however, be a more potent central stimulant, particularly in its effects on serotonergic transmission. Several fatalities from PMA have been reported in Australia, and here we report three recent fatalities that occurred in the midwestern United States in which each of the decedents believed that they were ingesting MDMA. Symptoms observed included agitation and bruxism, progressing to severe hyperthermia, convulsions, and hemorrhage. Blood was screened for drugs of abuse by enzyme immunoassay with the presence of amphetamines indicated in each case. Confirmation and quantitation for amphetamines was performed by gas chromatography-mass spectrometry. The deceased, two males ages 19 and 24 and a female age 18, had postmortem blood PMA concentrations of 1.07, 0.60, and 1.90 mg/L, respectively. PMA is not a contaminant of MDMA, and no MDMA was found in any of these cases. The primary metabolite of PMA is produced by O-demethylation to 4-hydroxyamphetamine, a reaction catalyzed by cytochrome P450 2D6. This enzyme is noted to be genetically polymorphic. Those with the "slow metabolizer" phenotype may be likely to have higher peak blood concentrations of PMA. Whether any of the decedents described herein were of the slow metabolizer phenotype is not known. Several groups have advocated the onsite use of the Marquis Test for the purpose of pill screening in efforts to distinguish PMA from MDMA. A dark purple is consistent with MDMA, whereas PMA imparts no color change in this test. PMA is often in the form of a white pill with a Mitsubishi symbol on one side. This design has been identified in at least one of these fatalities.

Home literacy activities and their influence on early literacy skills.

The relationship between the home environments of 66 children and their language and literacy development was examined. After accounting for child age, parent education, and child ability as indexed by scores on a rapid automatized naming task and Block Design of the WPPSI-R, shared book reading at home made no contribution to the prediction of the literacy skills of letter name and letter sound knowledge in kindergarten. In contrast, home activities involving letters predicted modest and statistically significant amounts of variance. For the areas of receptive vocabulary and phonological sensitivity, neither shared book reading nor letter activities were predictive. Follow-up to mid-Grade 2 underscored the importance of letter name/sound knowledge and phonological sensitivity in kindergarten in accounting for individual differences in later achievement in reading comprehension, phonological spelling, and conventional spelling.

The effect of variability of unattended information on global and local processing: evidence for lateralization at early stages of processing.

Visual objects can often be analyzed as hierarchical in structure, composed of local elements that are spatially arranged to form a global shape. The brain mechanisms involved in the analysis of hierarchical figures have been under considerable scrutiny in recent years, and one of the many interesting features that have emerged is that there is an asymmetry across the two hemispheres for global (right hemisphere) vs local (left hemisphere) processing. Event-related potentials (ERP) were used to examine selective attention to global or local levels of hierarchical figures to determine the stage of processing at which the asymmetry first emerges. Two conditions were tested, one in which unattended information was variable from trial to trial, and one in which it was not. The variability of unattended information influenced the lateralization of processing. Presentation of invariable, neutral distractors resulted in global/local processing asymmetries at early stages (P1). In contrast, presentation of variable, task-relevant distractors resulted in processing asymmetries that occurred at much later stages (N2). Our hypothesis is that lateralized enhancement of neural populations in extrastriate cortex results from both selective attention to locations in the visual field, as well as selective attention to global or local information. We suggest that unattended information that varies from trial to trial is processed in parallel with attended information, masking hemisphere biases for local vs global information at early stages of processing.

Demographic and psychosocial risk factors for preterm delivery in an active duty pregnant population.

The effects of work climate, pregnancy transitions stress, maternal medical conditions, health risk behaviors, psychological health, and demographic characteristics were examined among 269 pregnant military women. The study found that single and separated/divorced military women were at greater risk for preterm delivery than married women. Unmarried participants were more likely to belong to ethnic minorities, were lower ranking, less educated, and reported a greater number of medical conditions than married participants. Psychosocial variables distinguished the three marital status groups--married, single, and separated/divorced--but none of these variables was related to preterm delivery. In a logistic regression analysis, marital status was a more significant predictor of preterm delivery than were medical conditions.

Application of the bootstrap procedure provides an alternative to standard statistical procedures in the estimation of the vitamin B-6 requirement.

The bootstrap procedure is a versatile statistical tool for the estimation of standard errors and confidence intervals. It is useful when standard statistical methods are not available or are poorly behaved, e.g., for nonlinear functions or when assumptions of a statistical model have been violated. Inverse regression estimation is an example of a statistical tool with a wide application in human nutrition. In a recent study, inverse regression was used to estimate the vitamin B-6 requirement of young women. In the present statistical application, both standard statistical methods and the bootstrap technique were used to estimate the mean vitamin B-6 requirement, standard errors and 95% confidence intervals for the mean. The bootstrap procedure produced standard error estimates and confidence intervals that were similar to those calculated by using standard statistical estimators. In a Monte Carlo simulation exploring the behavior of the inverse regression estimators, bootstrap standard errors were found to be nearly unbiased, even when the basic assumptions of the regression model were violated. On the other hand, the standard asymptotic estimator was found to behave well when the assumptions of the regression model were met, but behaved poorly when the assumptions were violated. In human metabolic studies, which are often restricted to small sample sizes, or when statistical methods are not available or are poorly behaved, bootstrap estimates for calculating standard errors and confidence intervals may be preferred. Investigators in human nutrition may find that the bootstrap procedure is superior to standard statistical procedures in cases similar to the examples presented in this paper.

Menu design and selection for multicenter controlled feeding studies: process used in the Dietary Approaches to Stop Hypertension trial. DASH Collaborative Research Group.

Outpatient feeding studies are being used increasingly more often than inpatient studies because they are less expensive to conduct and less disruptive to participants' daily lives. Frequently, however, they are more difficult to implement. Studies involving multiple feeding centers add an additional layer of cooperation, coordination, and standardization to the already complex task of developing and delivering research diets. This was true for the 4-year Dietary Approaches to Stop Hypertension (DASH) trial, one of the first multicenter outpatient controlled feeding studies. This 4-center, randomized clinical trial was designed to compare the effects of 3 dietary patterns on blood pressure. After a year of development, 3 sets of 7-day cycle menus that met the study nutrient criteria and that were appropriate for varying food production routines and staffing patterns at the 4 clinical centers were adopted. The major development tasks were: defining methodologies to guide menu design and food production; selecting a nutrient database and calculating nutrient content of menus; evaluating and selecting the menus; and adjusting the menus for final use. The purpose of this article is to describe the steps and considerations in the design and selection of menus for the DASH trial, a process applicable to all well-controlled feeding studies.

Validation of diet composition for the Dietary Approaches to Stop Hypertension trial. DASH Collaborative Research Group.

The Dietary Approaches to Stop Hypertension trial involved 4 clinical sites at which 459 participants (in 5 cohorts) were fed 3 dietary patterns over 11 weeks per cohort. The 3 patterns were a control diet, a fruits and vegetables diet, and a combination diet. Before the intervention, key nutrient levels in each diet were validated at 2 energy levels (2,100 and 3,100 kcal) by chemical analysis of the prepared menus. During intervention, diets were sampled across all cohorts, sites, and energy levels, and 7-day menu cycle composites were assayed. In general, sodium, potassium, calcium, and magnesium in the validated menus for each diet/energy level met the nutrient targets, though moderate variability was evident among individual menus, particularly for potassium, calcium, and magnesium. However, as intended, there was clear separation and no overlap in mineral levels in individual menus of diets that were designed to differ. During intervention, macronutrient contents met nutrient goals. Sodium, potassium, calcium, and magnesium in the diets generally met target levels, though potassium in the fruits and vegetables diet was 11% to 23% below target. There were no consistent differences in nutrient levels between sites. The mean nutrient levels in the validated menus and diets sampled during intervention were in excellent agreement with each other, though sodium was somewhat higher (approximately 6%) in the diets from intervention vs validation. These results indicate the success of the quality control measures implemented and suggested consistent overall diet composition throughout the 28 months during which the study was conducted.

Dietary adherence in the Dietary Approaches to Stop Hypertension trial. DASH Collaborative Research Group.

Participants in controlled feeding studies must consume all study foods and abstain from all other foods. In outpatient studies in which adherence may be compromised by free-living conditions, promoting, documenting, and monitoring dietary adherence are necessary. In the Dietary Approaches to Stop Hypertension (DASH) trial, a thorough participant screening process, an orientation session, and a run-in feeding period before randomization aided in the selection of participants who would most likely adhere to the demands of the study protocol. Throughout the feeding period, various educational and motivational techniques were used to encourage DASH participants to adhere to the dietary protocol. Both objective and subjective methods documented excellent participant adherence. Daily monitoring of individual adherence was based on meal attendance, body weight measurements, and daily diaries. Urinary sodium, potassium, phosphorus, and urea nitrogen values and an anonymous poststudy survey were used to evaluate adherence at the end of the study. Most DASH participants adhered to the feeding regimen by consuming only study foods and no other foods. When adherence lapsed, participants generally cited the lack of menu variety as a reason. Successful participant adherence to the constraints of an outpatient controlled feeding study is possible with carefully selected participants and a variety of adherence-promoting strategies incorporated into the study protocol.

Translating the Dietary Approaches to Stop Hypertension diet from research to practice: dietary and behavior change techniques. DASH Collaborative Research Group.

The Dietary Approaches to Stop Hypertension (DASH) clinical trial demonstrated that a diet that emphasizes fruits, vegetables, and low-fat dairy products, includes whole grains, nuts, fish, and poultry, and is reduced in fats, red meats, sweets, and sugar-containing beverages can be highly effective in lowering blood pressure. The National High Blood Pressure Education Program now suggests the DASH diet for preventing and managing hypertension. For persons modifying their diets, the DASH diet offers varied choices. However, simultaneously modifying several dimensions of a diet can be challenging, even for knowledgeable and motivated persons. Persons who are uncertain about modifying their diet may become overwhelmed by the needed dietary changes. Dietitians and other health care practitioners can help patients adopt the DASH diet by exploring possible ambivalence, increasing motivation, and strengthening commitment to change; encouraging patients to select dietary modifications that will fit their lifestyle; and, finally, offering information about how to change their eating behavior. In this article, we offer dietary advice and counseling suggestions for tailoring interventions to match patients' readiness for adopting the DASH diet.

High-fat dairy product consumption increases delta 9c,11t-18:2 (rumenic acid) and total lipid concentrations of human milk.

Conjugated octadecadienoic acids (18:2, conjugated linoleic acids) have been shown to be anticarcinogenic and may influence growth and nutrient partitioning. The delta 9c,11t-18:2 isomer (rumenic acid, RA) is most common in both food sources and human tissues. To determine if maternal diet can influence milk RA concentration, breastfeeding women (n = 16) were enrolled in a 3-wk crossover study. Women initially consumed minimal amounts of food containing RA during week 1, then were assigned randomly to consume diets rich in high-fat dairy foods (and thus RA) during week 2 or 3. Milk was collected by complete breast expression twice during each experimental week. Current and chronic RA intakes were estimated by 3-d dietary records and food frequency questionnaires, respectively. Estimated chronic RA intakes ranged from 49 to 659 mg/d. Dietary RA intake was greater during the high compared to the low dairy period (291 +/- 75 vs. 15 +/- 24 mg/d, respectively; P < 0.0001). Milk contained more RA during the high than the low dairy period (13.5 +/- 0.1 vs. 8.2 +/- 0.4 mumol/g lipid, respectively; P < 0.0001). Milk lipid concentration was influenced by diet, such that lipid concentration was greater during the high than the low dairy period (46.6 +/- 5.0 vs. 38.3 +/- 1.6 mg/g milk, respectively; P < 0.05). Additionally, multiple regression analyses suggested that body mass index was the primary predictor of milk RA and lipid concentrations. In summary, these data indicate that both lipid and RA concentrations of human milk can be influenced by diet.