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Aim Nutritional interventions might prevent hypertension–related organ damage but are far to be fully defined. Coffee is one of the most used beverages all over the world. Many studies tried to define the optimal amount of coffee to understand whether coffee has a role in cardiovascular prevention. Thus, we evaluated heart and vascular damage in well–controlled hypertensives according to coffee consumption. Methods We evaluated 316 primary hypertensives (150F, 166M, aged 62.22±10.76) evaluated for target organ damage. The number of coffee cups per day was asked during the visit. Results The median coffee consumption was 2 cups per day and patients were subdivided into tertiles: Group 1, 0–1 cups 112 patients (57F, 55M; 64.21±10.91 y.), Group 2, 2 cups, 101 patients (53F; 48 M; 61.95±10.10 y.), Group 3, >2 cups, 103 patients (40F; 63M; 60.32±10.95 y.). No differences were seen in BMI, systolic and diastolic BP. Group 1 had a higher left ventricular mass than the other two groups (p= 0.0008 and p=0.019 respectively) while no difference there was between group 2 and 3. Similarly, Group 1 had a significant reduction in E/e’ ratio (p=0.042 and p=0.019, respectively). No significance was found between Group 2 and 3 for left ventricular mass and diastolic function. Group 3 had an increased intima–media thickness (p=0.004 and p=0.005 vs Group 1 and 2, respectively). Prevalence of carotid stenosis was lower in Group 3 (p=0.011 and p=0.039, respectively) and was comparable in Group 1 and 2. Conclusion Coffee consumption at least of 2 cups/day may have a role in prevention of heart remodelling and diastolic dysfunction.

Objective:Worldwide blood pressure control is achieved only in 40–50% of patients treated for hypertension, despite the availability of a considerable number of antihypertensive drugs from different pharmacological classes. Although there are many reasons for insufficient control of blood pressure

To investigate the relationship between lymphocyte decrease and cytogenetic response in individual patients undergoing radiotherapy.Peripheral blood lymphocytes obtained from 35 patients with pelvic and from 14 with head and neck tumours before and during radiotherapy were PHA-stimulated in vitro and the cultures prepared for the cytokinesis-block micronucleus test. For some patients only, the micronucleus test was carried out after 2 Gy in vitro X-irradiation, and 3-aminobenzamide (2 mM) was used to calculate the 3AB-index.The initially observed individual variation in the decrease of lymphocytes disappeared with increasing number of radiation exposures, reaching a stable level at about 500/microl lymphocytes in the blood. The slope of the relationship between the reciprocal of the lymphocyte decrease ratio and equivalent dose indicates the radiosensitivity of the lymphocyte pool in individual patients. The micronucleus test performed on lymphocytes obtained from patients during radiotherapy (in vivo) provided a lower cytogenetic response than the in vitro micronucleus yield for the same dose, so it was possible to calculate the cytogenetic recovery factor k. A correlation was found between the 3AB-index calculated before radiotherapy, and the recovery factor k.The 3AB-index, the micronucleus frequency after 2 Gy in vitro X-irradiation, and the cytogenetic recovery factor are proposed as predictive of individual response to radiotherapy.

We applied the cytokines-block micronucleus assay to observe the radiobiological response of human lymphocytes after X-ray treatment in the G0 and G1 phases. In addition, we used 3-aminobenzamide (3AB) to measure the 3AB index in the two phases. The experimental results show that at 2 Gy the MN yield and the 3AB index are dependent on the cell phase and show considerable inter-individual variability. The radiation-induced MN frequency obtained for 33 subjects is 0.470 +/- 0.063 for the G0 phase and 0.689 +/- 0.139 for the G1 phase; the 3AB index values are 0.326 +/- 0.144 and 0.067 +/- 0.058 for G0 and G1 phases, respectively. At the individual level, the 3AB index for the G1 phase correlates inversely with the cytogenetic effects observed in that phase. We discuss the possibility of applying the MN test combined with the 3AB index to lymphocytes at different phases to study the individual response to radiation (individual radiosensitivity).

The relationship between the repair processes occuring at the G2 phase of the cell cycle and cytogenetic damage in ataxia telangiectasia (AT) cells was studied. Lymphoblastoid cells derived from normal, heterozygote AT (HzAT) and three AT patients were exposed to X-rays or fission neutrons and post-treated with inhibitors of DNA synthesis/repair, such as inhibitors of DNA polymerases alpha, delta and epsilon (cytosine arabinoside, ara-C; aphidicolin, APC; buthylphenylen-guanine, BuPdG) or ribonucleotide reductase (hydroxyurea, HU). A strong increase of radiation-induced chromosomal aberrations was observed in normal and HzAT cells post-treated with ara-C, APC and HU, but not in the presence of BuPdG. No enhancing effect was observed in cells derived from AT patients, except for HU post-irradiation treatment. These results suggest that the enzymes that can be inhibited by these agents are not directly involved in the repair of radiation damage induced in G2 cells from AT patients, indicating that probably the AT cells that we used lack the capability to transform the primary DNA lesions into reparable products, or that AT cells might contain a mutated form of DNA polymerase resistant to the inhibitors.

The effects of aliphatic alcohol co-solvents on the nature of inclusion complexes formed between 2-anilinonaphthalene-6-sulfonic acid (2,6-ANS) and β- or γ-cyclodextrin were studied with the use of steady-state and time-resolved fluorescence spectroscopy. Complementary information about the effects of alcohol on cyclodextrin (CD) inclusion complexation has been obtained. The fluorescence lifetimes are recovered from multifrequency phase and modulation experiments in concert with a global analysis scheme. In all cases, the best fitting model contained two decay times. One of the components of the intensity decay is short lived and discrete and the other is a longer-lived distributed component. Evidence from the emission peak intensity, the center and width of the lifetime distribution, and the molar fraction of lifetime components indicates that alcohol modifiers have two distinct effects on the cyclodextrin inclusion complex. First, alcohol co-solvents can disrupt the 2,6-ANS-CD complex through competitive binding with the CD cavity, and to a lesser extent they increase the bulk solvent hydrophobicity. Second, alcohols can enhance the stability of certain 2,6-ANS inclusion complexes by formation of higher-order complexes (2,6-ANS-CD-ROH n). These two effects are governed by the cavity size and the structure and concentration of the alcohol co-solvents. These observations are consistent with the roles of the van der Waals interactions, the hydrophobic effect, and the stearic effects as important factors in CD inclusion complexation. Finally, the average rotational correlation time, recovered from steady-state anisotropy experiments, indicates that the rotational dynamics of the 2,6-ANS-CD complex are regulated by the size and concentration of the alcohol co-solvent.

We have previously demonstrated that high-affinity PGE receptors are present on purified cardiac sarcolemmal (SL) membrane from bovine heart (Lopaschuk et al. (1989) Circ. Res. 65, 538-545). In this study we determined whether PGI2 receptors are also present on the cardiac SL membrane. Due to the extreme lability of prostacyclin (PGI2) under physiological conditions, the PGI2 analogue, Iloprost was substituted for PGI2. 3H-Iloprost specifically bound to two sites on the SL membrane; one of high affinity (Kd = 0.3 nM, Bmax = 97.0 fmol/mg SL), and one of lower affinity (Kd = 20.6 nM, Bmax = 1589 fmol/mg SL). Competition studies demonstrated that the concentrations of PGE2 and PGE1 necessary to displace 50% of the specific binding of 20 nM [3H]Iloprost on cardiac SL were 15-fold lower than the concentrations of unlabelled Iloprost necessary to displace 50% of binding. In contrast, a 15-fold higher concentration of unlabelled Iloprost was needed to displaced 50% of specific binding of 2 nM [3H]PGE2 compared to the concentrations of PGE1 or PGE2 required to displace 50% of [3H]PGE2 binding. In summary, our results indicate that a prostacyclin receptor is present on the cardiac sarcolemmal membrane, and that PGI2 competes for the same receptor site as PGE2.

To evaluate the influence of inhibitors of DNA synthesis/repair on the yield of chromosomal aberrations in the G2 phase of the cell cycle, whole-blood cultures of human lymphocytes were exposed to various doses of fission neutrons or X-rays and treated post-irradiation during the last 2.45 h before harvesting, with 5 mM caffeine, 5 mM hydroxyurea (HU) and 0.05 mM cytosine arabinoside (ara-C). The presence of caffeine and HU strongly potentiated the yield of chromatid-type aberrations induced by both neutrons and X-rays. No potentiating effect, except at the highest dose of neutrons, was observed when irradiated cells were subsequently treated with ara-C. Since ara-C strongly potentiated the frequency of chromatid aberrations induced in G2 lymphocytes by X-rays, the results presented here indicate that fission neutrons produce a smaller proportion of lesions, the repair of which can be inhibited by ara-C, compared with the number produced by X-rays. In addition, neutron-induced mitotic delay was shortened by treatment with caffeine, mainly within the first 2 h after irradiation.

Over the last several decades the communications industry has developed small, high-light transmitting fiber-optic materials. Because of their inherently non-perturbing nature fiber optics have found wide spread use in many diverse areas of analytical spectroscopy. Of all the spectroscopic techniques, fiber-optic-based fluorescence has probably enjoyed the greatest popularity. Unfortunately, while successful analyses have been achieved via fiber-optic probes, only a fraction (that is, spectral information) of the total information content from the fluorescence process has been utilized. In this paper, recent results from our laboratory are presented for the successful implementation of the remaining dynamic and steady-state fluorimetric measurements in conjunction with fiber-optic sensing.

A selective fiber-optic-based immunosensor for haptens is described and characterized. In order to construct a sensor for different analytes, a prescribed reaction protocol is followed and only the recognition element [F(ab′) antibody fragment] has to be changed. The dynamic range of this sensor is about two orders of magnitude and the detection limits are at least 25 nM (25-μ1 volume). By using steady-state fluorescence and classical ultra-high-vacuum surface analytical techniques, the effects of regeneration media, reaction and storage times and interferents on the sensor response were studied.

Fluorescence lifetimes are reported for a series of anilinonaphthalene sulfonate (ANS) probe molecules complexed with β-cyclodextrin (β-CD). The fluorescence decay kinetics are recovered by multifrequency phase and modulation measurements in concert with a global analysis scheme. In all cases studied, a continuous Lorentzian distribution of lifetimes is observed, resulting from the dynamical nature of the ANS-β-CD complex and free ANS. Trends are discussed and comparisons made between bound and free fluorophore and between different isomeric ANS structures.

A bifurcated fiber-optic sensor is reported that uses immobilized β-cyclodextrin (β-CD) as the sensing agent. The sensor forms moderately selective inclusion complexes between β-CD and many guest molecules. On complexation, a weakly fluorescent molecule often exhibits a significant increase in emission yield. The linear dynamic range of this sensor extends well over 2.5 orders of magnitude. Detection limits (signal-to-noise ratio=3) are as low as 4 nM for sample volumes as small as 15μl (60 fmol). This is an improvement of over two orders of magnitude compared with detection with a conventional “bare” fiber-optic probe. The sensor is simple to fabricate, has a useful lifetime of at least 5 months, is suitable for laser or arc lamp excitation sources and can be reconditioned rapidly.

Discussed in this paper is the evolution of work that started, since March 1989, by using the M. Fleischmann and S. Pons method and ended by using thin palladium wires electrolyzed in an electrolyte consisting of slightly acidic heavy alcohol-water solution containing thorium (Th) and mercury (Hg) salts at micromolar concentrations. The resulting large and dynamic loading of the Pd wires was studied. The recent use of thorium instead of strontium resulted in thermal anomalies and detection of new elements in larger amounts. The results with Sr are qualitatively in agreement with what was found by Y. Iwamura (Mitsubishi Heavy Industries, Yokohama-Japan) using multilayers of Pd-CaO-Pd-Sr in flowing deuterium gas. Most results seem to be in agreement with a “multi-body resonance fusion of deuterons” model recently developed by A.Takahashi (Osaka University-Japan).

We have investigated and compared DNA damage and cell killing induced in human and equine lymphocytes after in vitro X-irradiation. Our data show that the cytogenetic and the lethality effects are both greater in equine lymphocytes, but that the difference is wider for lethality. The ratios between doses inducing the same effect are 1.3, 1.7 and 9.4 for the number of binucleated cells with micronuclei, micronucleus frequency in binucleated cells and DNA synthesis inhibition, respectively. The very different radiosensitivity observed for the two mammalian species encourages us to use their lymphocytes in cell radiobiology studies.

We have applied the cytokinesis-block micronucleus assay to peripheral blood lymphocytes of patients undergoing radiotherapy in pelvic and pulmonary sites, in order to evaluate the individual cytogenetic response. Our cytogenetic data correlated with the equivalent whole-body dose are homogeneous and compare well with the data presented by other authors. We have used an exponential mathematical formula to calculate the attenuation of the cytogenetic effect with time. The k coefficient (cytogenetic recovery factor) in the formula expresses the degree of attenuation. In lymphocytes from patients after radiotherapy, the trend of the micronucleus frequency observed after 2 Gy of in vitro X-irradiation demonstrates that the cytogenetic effect obtained in vitro is added to that obtained in vivo. The k coefficient is inversely proportional to the micronucleus frequency observed after 2 Gy in vitro. The micronucleus assay and the cytogenetic recovery factor are proposed as suitable diagnostic tools for application in the field of radiotherapy.

We applied the cytokines-block micronucleus assay to observe the radiobiological response of human lymphocytes after X-ray treatment in the G0 and G1 phases. In addition, we used 3-aminobenzamide (3AB) to measure the 3AB index in the two phases. The experimental results show that at 2 Gy the MN yield and the 3AB index are dependent on the cell phase and show considerable inter-individual variability. The radiation-induced MN frequency obtained for 33 subjects is 0.470 +/- 0.063 for the G0 phase and 0.689 +/- 0.139 for the G1 phase; the 3AB index values are 0.326 +/- 0.144 and 0.067 +/- 0.058 for G0 and G1 phases, respectively. At the individual level, the 3AB index for the G1 phase correlates inversely with the cytogenetic effects observed in that phase. We discuss the possibility of applying the MN test combined with the 3AB index to lymphocytes at different phases to study the individual response to radiation (individual radiosensitivity).

In 28 blood samples from 21 patients undergoing 131I treatment after surgical thyroidectomy for cancer, the micronucleus (MN) frequency observed in peripheral blood lymphocytes (MN-test on binucleated cells) had a weighted mean of 0.044 +/- 0.006 (SEM), which was significantly different (p0.001) from that observed in 93 healthy individuals (0.025 +/- 0.001). The MN frequency (F(MN)) of the patients correlated fairly well (R = 0.736) with the modified activity (Amod) calculated by the following equation: [formula: see text] where Ai is the 131I activity on a determined day, e the logarithm base, di the number of days that have passed between the determined day and the day when the blood was drawn, and k is a day coefficient, defined in this context as the "daily attenuation factor". The use of the value of 0.0003 for k allowed the following equation to be obtained: F(MN) = 7.9 x 10(-5) (+/- 1.4 x 10(-5)).Amod + 0.014 (R = 0.736) The MN frequency was used to estimate, by our DOSIME program, the dose (Gy) received at the individual level in the 131I treatment. In these subjects the calculated dose was well correlated with Amod by the relationship: DBio = 0.0009 (+/- 0.0002).Amod + 0.0675 (R = 0.755) 3-aminobenzamide (3AB), an inhibitor of the poly(ADP-ribose)polymerase enzyme involved in DNA repair, induced and increase in X-ray cytogenetic damage (MN yields), evaluated at the individual level using the 3AB-index (I-3AB). The index was obtained from the MN-yield count after x-irradiation with (MN + 3AB) and without (MN - 3AB) 3AB, using the following formula: I = 1-(MN - 3AB/MN + 3AB).(ABSTRACT TRUNCATED AT 250 WORDS)

The comparative study of different species could be of interest, both applied and pure, to the field of cytogenetic damage induced by genotoxic agents. For as accurate as possible an evaluation of the inter-species response differences to radiation, we have carried out a comparison between the behaviors of human and canine lymphocytes, using the micronucleus assay (MN test) according to the cytokinesis-block method. Up to 4 Gy doses, canine lymphocytes have been found to be about three times more radiosensitive than human lymphocytes, due to blastization inhibition (binucleation failure), and, for 1 and 2 Gy doses, about 1.3 times more radiosensitive, due to MN yields. We discuss whether the differing chromosome number (dog 78 and man 46) could have any effect on the cytogenetic response. 3-Aminobenzamide, which inhibits poly(ADP-ribose)polymerase activity, is able to increase the genotoxic effect of X-rays in human lymphocytes, with a different response at the individual level. The same phenomenon with the same characteristics is also found in canine lymphocytes at the inter-individual level. Our in vitro radiobiological study confirms that the cytogenetic response obtained in blood from selected breeds of mammalian species can be utilized for applications in environmental studies.

When physical dosimetry is unavailable, the biological dosimetry of ionizing radiations is considered the best method for evaluating the individual absorbed dose. In order to apply this method, it is essential to know the dose-response relationship (calibration effect) regulating the phenomenon. The results obtained on human lymphocytes after in vitro X-ray treatment are presented. Two cytogenetic methods were used: the dicentric chromosomes assay in metaphase cells and the micronuclei assay in binucleated cells. The two were compared in order to verify the best utilization of each in the context of prevention and radioprotection. For the dicentric assay, 20 samples were treated with increasing doses of X-rays (from 0.5 to 2.0 Gy) and for the micronuclei assay, 25 samples were treated with doses from 0.1 to 4.0 Gy. The biological response was then evaluated. The data obtained were fitted by a second-grade polynomial regression. The dose-response relationship for the dicentric yield was F(dic) = 0.01-0.2D + 0.091D2 (regression coefficient better than 0.95); for the micronuclei yield, it was F(mn) = 0.015 + 0.043D + 0.083D2 (regression coefficient better than 0.97). The absorbed dose in exposed individuals was evaluated by the micronuclei frequency using a mathematical process (inverse prediction) that takes into account the measurement error and the 95% confidence intervals of the calibration curve. For this purpose a programme in Basic (DOSIME) was generated that was capable of estimating the dose and its variability. Since the micronuclei assay is simple and quick to carry out, it permits extensive screening and facilitates the identification of radiosensitive subjects. The estimated dose values of individuals submitted to radiotherapy are also given.

Among the methods of biological dosimetry of ionizing radiation, we propose the cytokinesis-block micronucleus assay for the measurement of the individual dose absorbed. The dose-response curve was determined for in vitro-irradiated lymphocytes from 25 individuals. The dose-response relationship, fitted by the linear-quadratic function, was F(MN) = 0.015 (+/- 0.0016) + 0.043 (+/- 0.0075).D + 0.083 (+/- 0.0045).D2. Our results are compared with those of other authors. 3-aminobenzamide (3AB) combined with X-rays were used to evaluate the micronucleus dose-response relationship in blood from 14 individuals. While it is known that 3AB inhibits poly(ADP-ribose) polymerase activity in vitro, we demonstrate that it also increases the X-ray-induced micronucleus yields. The resulting dose-response relationship varies from subject to subject. The possibility of using this approach to identify the individual radiosensitivity level is discussed.

The effects of UV light or X rays in cultured Chinese hamster cells have been initially analyzed in terms of cell growth and colony survival. On the basis of these preliminary observations the induction of micronuclei has been studied on the same in vitro system. The increase in micronuclei yield appears to be dose-dependent, but also to vary according to the protocol used for micronuclei preparation. In general, the results confirm the hypothesis that micronucleus production is a dynamic phenomenon.

Induction and repair of DNA strand breaks in asynchronous and synchronized cultures of human lymphocytes was investigated by using the alkaline DNA-unwinding technique followed by chromatography on hydroxylapatite. Strand break rejoining in exponentially growing human PHA stimulated lymphocytes, irradiated with 20 Gy of X-rays, is temperature-dependent, being fast at 37 degrees C (half-time of a few minutes), and very slow at around 4 degrees C. In synchronized cells irradiated with the same X-ray dose, the repair capacity increases during S phase reaching its maximum when DNA is entirely duplicated.

The effect of X-irradiation on thymidine transport in human lymphocytes PHA stimulated was investigated. Mediated transport sistem, the predominant mechanism at low extracellular concentration of thymidine (less than 10(-7) M) in the medium is highly radiosensitive. The transport sistem was damaged considerably by high doses of X-rays (at least until 10 Krad); the decrease of thymidine uptake was a function of the time of incubation after irradiation. It suggest that repair mechanisms are not involved at high doses of X-rays within 120 minutes of incubation.

Thermodynamic parameters and stoichiometries for the binding of anilinonaphthalenesulfonates to beta-cyclodextrin are obtained from steady-state fluorescence intensity and anisotropy measurements. Specifically, formation constant, enthalpy, and entropy values are obtained for complexes of beta-cyclodextrin with eight different substrate molecules at five different temperatures and six different pH values, and their associated errors are given. We propose an explanation of the relative magnitudes of the values obtained with regard to the geometry of the substrate and the importance of the various noncovalent interactions responsible for the complexation.

Human lymphocytes from peripheral blood are considered to be among the most radiosensitive cells in vivo (1) as well as in vitro (2–3).