Baseline drinking water consumption and changes in body weight and waist circumference at 2-years of follow-up in a senior Mediterranean population.

BACKGROUND & AIMS: The association between drinking water consumption and adiposity has been poorly explored. Therefore, we aimed to analyse the associations between the frequency of drinking water consumption and body weight and waist circumference changes in an elderly Mediterranean cohort. METHODS: A total of 1832 elderly participants (aged 55-75 years) with metabolic syndrome from the PREDIMED-Plus study with baseline data on drinking water and other beverages assessed by a validated 32-item Spanish fluid-intake questionnaire and with data on body weight (BW) and waist circumference (WC) at 1-year and 2-year were included in these prospective analyses. Multivariable linear regression models were fitted to assess the ß-coefficients and 95% confidence interval (CI) for BW and WC changes in terms of categories of baseline drinking water consumption (tap water and bottled water). The theoretical effect on BW and WC of replacing several beverages with drinking water was assessed using mathematical models. RESULTS: The baseline frequency of drinking water consumption was inversely associated with 1-year and 2-year changes in BW. ß-coefficients (95%CI) across categories of water consumption (<2.5, 2.5 to <5, 5 to < 7.5, ≥7.5 servings/d) expressed in % of weight changes at 2 years of follow-up were 0.0, -0.80 (-1.48, -0.12), -1.36 (-2.18, -0.54), and -1.97 (-3.09, -0.86), respectively. Individuals in the two highest categories of drinking water consumption (5 to < 7, and ≥7.5 servings/d) also showed a higher decrease in WC (expressed as % of change) after 2 years of follow-up: -1.11 (-1.96, -0.25) and -1.45 (-2.66, -0.24) compared to the reference intake (<2.5 servings/day), after adjustment for potential confounding factors. The theoretical replacement of soups, beers, spirits, hot beverages, dairy beverages, and other beverages group with drinking water was associated with greater reductions in BW at one- and two-years of follow-up. CONCLUSIONS: Drinking water consumption was inversely associated with 2-year adiposity changes in an elderly Mediterranean cohort at high cardiovascular risk. Our results also suggest that the consumption of drinking water instead of energy-containing beverages is associated with lower weight gain. THE TRIAL REGISTRATION: ISRCTN89898870.

Nature of fiber-coupled detector responsivity measurements at 0.1% using a primary standard.

We demonstrate the capability to measure the absolute power responsivity of optical fiber-coupled detectors at an expanded uncertainty of 0.1%, by direct comparison with a cryogenic primary standard. To facilitate synchronous power measurements, commercial all-fiber beam-splitters direct laser diode light simultaneously to the device under test and the primary standard. We investigate the use of single-mode, polarisation maintaining, and photonic crystal fibers to access the cryogenic standard, and report a reduction in the temperature dependent effective refractive index of these fibers of 0.1%, 0.15% and 0.3% respectively in going from room temperature to 5 K. We also evaluate the polarisation dependent loss of the beam-splitters, the stability of the beam-splitter ratio between the cryogenic detector and the device under test and the temporal and modal stability of the Fabry-Pérot laser diode sources. It is shown that the stability of the optical fiber beam-splitters limits the overall performance of the measurement system to an expanded uncertainty of 0.1%.

Children with Asthma and Communication with Healthcare Provider: Instrument Development.

PURPOSE: Communication among healthcare providers, caregivers and children with asthma is challenging and sometimes may exclude the child. This may result in delay in recognizing and responding appropriately to asthma symptoms. The purpose was to test an instrument's subscale for content validity related to communication with the healthcare provider by examining age appropriateness, readability and clarity for children with asthma. DESIGN AND METHODS: This was a mixed method explanatory sequential design to examine age appropriateness, readability and clarity for a 15-item subscale of an instrument for children. The qualitative arm (focus groups) was used to enrich the questionnaire. The sample included children ages 8 to 12 with asthma (N = 25). RESULTS: The perspective of children with asthma provided enriched information to influence the development of instrument subscale on communication. CONCLUSIONS: The subscale revealed internal consistency with Cronbach Alpha 0.85. One of the children reported that using the term "provider" was clearer as oppose to healthcare provider. Children participating in the study found readable and clear. A readability analysis revealed the items were readable at a 6th grade level. PRACTICE IMPLICATION: Although the instrument is designed for primary care providers (physicians, nurse practitioners, physician assistants), the information gained from this pilot increases understanding about including the child in a triadic discussion. Further research will lead to next step toward computing reliability of the full measure and a factor analysis.

Bilateral Optical Power Meter Comparison Between NIST and CENAM.

We describe the results of a comparison of reference standards between the National Institute of Standards and Technology (NIST-USA) and Centro Nacional De Metrología (CENAM-Mexico). Open beam (free field) and optical-fiber-based measurements at wavelengths of 1302 nm and 1546 nm are reported. Both laboratories' reference standards were compared by means of a temperature-controlled optical trap detector. Measurements showed a largest difference of less than 3.4 parts in 10(3), which is within the combined expanded (k = 2) uncertainty for the laboratories' reference standards.

Phenoloxidase activity in the hemolymph of the spiny lobster Panulirus argus.

The prophenoloxidase activating system plays a major role in the defense mechanism of arthropods. In the present study, the phenoloxidase activity and its location in the hemolymph of the spiny lobster Panulirus argus is presented. Phenoloxidase activity was observed in the hemocyte lysate supernatant (HLS) and plasma after their incubation with trypsin. Higher amounts of trypsin were required to activate the HLS prophenoloxidase, due to the presence of a trypsin inhibitor in this fraction. Activation of prophenoloxidase was found when HLS was incubated with calcium, with an optimal pH between 7.5 and 8. This spontaneous activity is due to the prophenoloxidase activating enzyme, a serine proteinase that activates the prophenoloxidase once calcium ions were available. SDS was able to induce phenoloxidase activity in plasma and hemocyte fractions. Prophenoloxidase from HLS occurs as an aggregate of 300kDa. Electrophoretic studies combining SDS-PAGE and native PAGE indicate that different proteins produced the phenoloxidase activity found in HLS and plasma. Thus, as in most crustaceans, Panulirus argus contains a prophenoloxidase activating system in its hemocyte, comprising at least the prophenoloxidase activating enzyme and the prophenoloxidase. Finally, it is suggested that phenoloxidase activity found in plasma is produced by hemocyanin.

Ecological impacts of the microsporidian parasite Pleistophora mulleri on its freshwater amphipod host Gammarus duebeni celticus.

The microsporidian parasite, Pleistophora mulleri, infects the abdominal muscle of the freshwater amphipod Gammarus duebeni celticus. We recently showed that P. mulleri infection was associated with G. d. celticus hosts being more vulnerable to predation by the invasive amphipod Gammarus pulex. Parasitized G. d. celticus also had a reduced ability to prey upon other co-occurring amphipods. We suggested the parasite may have pervasive influences on host ecology and behaviour. Here, we examine the association between P. mulleri parasitism and parameters influencing individual host fitness, behaviour and interspecific interactions. We also investigate the relationship between parasite prevalence and host population structure in the field. In our G. d. celticus study population, P. mulleri prevalence was strongly seasonal, ranging from 8.5% in summer to 44.9% in winter. The relative abundance of hosts with the heaviest parasite burden increased during summer, which coincided with high host mortality, suggesting that parasitism may regulate host abundance to some degree. Females were more likely to be parasitized than males and parasitized males were paired with smaller females than unparasitized males. Parasitism was associated with reduction in the host's activity level and reduced both its predation on the isopod Asellus aquaticus and aggression towards precopula pairs of the invasive G. pulex. We discuss the pervasive influence of this parasite on the ecology of its host.

Evaluación toxicológica de las tabletas de Acimín: un suplemento nutricional de calcio magnesio de origen natural / Toxicological evaluation of Acimin tablets: a calcium and magnesium suplement of natural origin

Las sales de calcio y magnesio son utilizadas como suplementos nutricionales obtenidas a partir de fuentes naturales dentro de las cuales se encuentra la dolomita, la cual es un mineral formado por un complejo doble de carbonato de calcio y magnesio. En la formulación de suplementos nutricionales a partir de la dolomita y en la búsqueda de una mayor biodisponibilidad, se obtuvo una materia prima en forma de citrato de calcio y magnesio a partir de la dolomita, la cual fue utilizada para la fabricación de las tabletas masticables de Acimín. El objetivo de nuestro estudio se centró en la evaluación toxicológica preclínica de estas tabletas, para lo cual se realizó un ensayo de toxicidad aguda oral en ratas Wistar de ambos sexos administrando la dosis de 2000 mg/kg, un ensayo de irritación de mucosa oral a dosis repetidas en hámsters Sirios Dorados hembras y un ensayo de irritacion de mucosa gástrica en ratas istar machos (250 - 300 g), aplicando las dosis de 2000, 1000 y 500 mg/kg. Como resultado se obtuvo que las tabletas de Acimín no poseen toxicidad significativa en el ensayo de toxicidad aguda oral (DL50>2000 mg/kg), no son irritantes de la mucosa oral (índice de irritacion de 0) y producen acidez e irritación sobre la mucosa gástrica a la dosis de 2000 mg/kg (AU)

The kinetic basis of peptide exchange catalysis by HLA-DM.

The mechanism by which the peptide exchange factor HLA-DM catalyzes peptide loading onto structurally homologous class II MHC proteins is an outstanding problem in antigen presentation. The peptide-loading reaction of class II MHC proteins is complex and includes conformational changes in both empty and peptide-bound forms in addition to a bimolecular binding step. By using a fluorescence energy transfer assay to follow the kinetics of peptide binding to the human class II MHC protein HLA-DR1, we find that HLA-DM catalyzes peptide exchange by facilitating a conformational change in the peptide-bound complex, and not by promoting the bimolecular MHC-peptide reaction or the conversion between peptide-receptive and -averse forms of the empty protein. Thus, HLA-DM serves essentially as a protein-folding or conformational catalyst.

The folding and structural integrity of the first LIN-12 module of human Notch1 are calcium-dependent.

Notch1 is a member of a conserved family of large modular type 1 transmembrane receptors that control differentiation in multicellular animals. Notch function is mediated through a novel signal transduction pathway involving successive ligand-induced proteolytic cleavages that serve to release the intracellular domain of Notch, which then translocates to the nucleus and activates downstream transcription factors. The extracellular domain of all Notch receptors have three iterated LIN-12 modules that appear to act as negative regulatory domains, possibly by limiting proteolysis. Each LIN-12 module contains three disulfide bonds and three conserved aspartate (D) or asparagine (N) residues. To begin to understand the structural basis for LIN-12 function, the first LIN-12 module of human Notch1 (rLIN-12.1) has been expressed recombinantly in Escherichia coli and purified in a reduced form. In redox buffers, rLIN-12.1 forms only one disulfide isomer in the presence of millimolar Ca2+ concentrations, whereas multiple disulfide isomers are observed in the presence of Mg2+ and EDTA. Further, mutation of conserved residues N1460, D1475, and D1478 to alanine abolishes Ca2+-dependent folding of this module. Mass spectrometric analysis of partially reduced rLIN-12.1 has been used to deduce that disulfide bonds are formed between the first and fifth (C1449-C1472), second and fourth (C1454-C1467), and third and sixth (C1463-C1479) cysteines of this prototype module. This arrangement is distinct from that observed in other modules, such as EGF and LDL-A, that also contain three disulfide bonds. One-dimensional proton nuclear magnetic resonance shows that Ca2+ induces a dramatic increase in the extent of chemical shift dispersion of the native rLIN-12.1 amide protons, as seen for the Ca2+-binding LDL-A modules. We conclude that Ca2+ is required both for proper folding and for the maintenance of the structural integrity of Notch/LIN-12 modules.

Effect of DIMBOA on growth and digestive physiology of Sesamia nonagrioides (Lepidoptera: noctuidae) larvae.

The hydroxamic acid 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) was assessed for its effect on growth and digestive physiology of larvae of the stalk corn borer Sesamia nonagrioides Lef. Nutritional indices and activities of some digestive and detoxification enzymes were determined for larvae feeding on a DIMBOA-containing diet for the first two days of the third instar (short-term feeding assays), and from neonates to third instar (long-term feeding assays). DIMBOA reduced the relative growth rate and the efficiency of conversion of ingested food without affecting the relative consumption rate in long-term feeding assays, but it had no effect in short-term assays. Moreover, elastase-like activity was significantly increased by DIMBOA in short-term feeding assays, whereas microsomal oxidase activity was increased and esterase activity was reduced in long-term feeding assays. In vitro, DIMBOA inhibited the activities of carboxypeptidases, aminopeptidase, glutathione S-transferase and esterase, but it had no effect on trypsin, chymotrypsin and elastase. The implications of the altered levels of proteases and detoxification enzyme activities on the digestive physiology of larvae feeding on DIMBOA-containing diets are discussed.

[Relationship between HLA antigens and the HIV infection in patients from the state of Zulia]. / Estudio de la relación entre antígenos HLA y la infección por VIH en pacientes del estado de Zulia.

PURPOSE: Some genetic factors associated to the HLA system phenotypes may allegedly predispose to the development of infection in patients exposed to the human immunodeficiency virus (HIV). So the aim of this study was to assess if certain HLA antigens are positive or negative risk factors in the development of AIDS in Zulia State. PATIENTS AND METHODS: A total of 62 samples were studied, 31 from HIV seropositive subjects and 31 form healthy individuals. The patients were subclassified into four groups in accordance with Atlanta's CDC guidelines. Tests for histocompatibility including HLA-A-B-C, DR and DQ typing were performed with Terasaki's technique. VIH positivity was determined by ELISA and confirmed by Western Blot. The statistical evalub1p4n was performed with the chi 2 test for antigen frequency comparison, the relative risk (RR) was estimated with the Ryder and Svelgaard test, and the inferential analysis was made by means of non-parametric statistics. RESULTS: Most patients were included in CDC's groups II and IV, 48.4% and 29.0%, respectively. Increased B35 and DQw2 and decreased B39 and DR2 antigens were found when comparing the HLA distribution in the sample and the antigenic frequency of the population. RR > 1 was observed in the infected patients A for A1, A3, A10, A11, B5, B7, B12, B14, B35, B61, CW4, DR4, DRW52 and DQW2 HLA antigens. A positive association between symptomatic infected patients and antigen B35 was present (X = 7.045). CONCLUSION: The findings reported here suggest that antigen B35 is a major risk factor for the development of AIDS.

Instrumental conditioning of diastolic blood pressure in essential hypertensive patients.

Eighteen male essential hypertensive patients participated in an experiment designed to compare two strategies for controlling high blood pressure. Each strategy was derived from the instrumental learning literature, and the aim was to treat the blood pressure response as an operant and determine the most effective conditioning procedure for manipulating it. The results demonstrate that patients could be conditioned to lower blood pressure by 20% to 30% over a period as brief as four days by providing an external signal and verbal praise contingent upon each reduction in diastolic pressure that met a pre-set criterion.