Individualized mycophenolate mofetil dosing based on drug exposure significantly improves patient outcomes after renal transplantation

Efficacy and safety of mycophenolate mofetil (MMF) may be optimized with individualized doses based on therapeutic monitoring of its active metabolite, mycophenolic acid (MPA). In this 12-month study, 137 renal allograft recipients from 11 French centers receiving basiliximab, cyclosporine A, MMF and corticosteroids were randomized to receive either concentration-controlled doses or fixed-dose MMF. A novel Bayesian estimator of MPA AUC based on three-point sampling was used to individualize doses on posttransplant days 7 and 14 and months 1, 3 and 6. The primary endpoint was treatment failure (death, graft loss, acute rejection and MMF discontinuation). Data from 65 patients/group were analyzed. At month 12, the concentration-controlled group had fewer treatment failures (p = 0.03) and acute rejection episodes (p = 0.01) with no differences in adverse event frequency. The MMF dose was higher in the concentration-controlled group at day 14 (p < 0.0001), month 1 (p < 0.0001) and month 3 (p < 0.01), as were median AUCs on day 14 (33.7 vs. 27.1 mg*h/L; p = 0.0001) and at month 1 (45.0 vs. 30.9 mg*h/L; p < 0.0001). Therapeutic MPA monitoring using a limited sampling strategy can reduce the risk of treatment failure and acute rejection in renal allograft recipients 12 months posttransplant with no increase in adverse events.

Acute angiotensin-converting enzyme inhibition increases the plasma level of the natural stem cell regulator N-acetyl-seryl-aspartyl-lysyl-proline

Angiotensin I-converting enzyme (ACE) has two homologous active NH2- and COOH-terminal domains and displays activity toward a broad range of substrates. The tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) has been shown to be hydrolyzed in vitro by ACE and to be a preferential substrate for its NH2-terminal active site. This peptide is a regulatory factor of hematopoiesis which reversibly stem cells and normal early progenitors into S-phase. We found that a single oral dose of 50 mg of the ACE inhibitor, captopril, when administered to eight healthy subjects in a double-blind, crossover, placebo-controlled study, massively increased the plasma level of Ac-SDKP. ACE inhibition by captopril induced a 90-99% inhibition of in vitro [3H]Ac-SDKP hydrolysis and a long-lasting 5.5-fold (range: 4-8.5-fold) increase in the plasma levels of Ac-SDKP. These results demonstrate that Ac-SDKP is the first natural peptide hydrolyzed by the NH2-terminal domain of ACE not only in vitro but also in vivo, confirming that both catalytic sites of ACE are physiologically active. Our data suggest that ACE may also be implicated in the process of hematopoietic stem cell regulation, by permanently degrading this natural circulating inhibitor of cell entry into S-phase.

The hemoregulatory peptide N-acetyl-Ser-Asp-Lys-Pro is a natural and specific substrate of the N-terminal active site of human angiotensin-converting enzyme

Angiotensin I-converting enzyme (ACE) is a zinc-dipeptidyl carboxypeptidase, which contains two similar domains, each possessing a functional active site. Respective involvement of each active site in the degradation of the circulating peptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), a negative regulator of hematopoietic stem cell proliferation, was studied by using wild-type recombinant ACE and two full-length mutants containing a single functional site. Both the N- and C-active sites of ACE exhibit dipeptidyl activity toward AcSDKP, with Km values of 31 and 39 microM, respectively. However, the N-active site hydrolyzes the peptide 50 times faster compared with the C-active site, with kcat/Km values of 0.5 and 0.01 microM-1.s-1, respectively. The predominant role of the N-active site in AcSDKP hydrolysis was confirmed by the inhibition of hydrolysis using a monoclonal antibody specifically directed against the N-active site. The N-domain specificity for AcSDKP will aid the identification of specific inhibitors for this domain. This is the first report of a highly specific substrate for the N-active site of ACE, with kinetic constants in the range of physiological substrates, suggesting that ACE might be involved via its N-terminal active site in the in vivo regulation of the local concentration of this hemoregulatory peptide.

Effects of endothelin-1 on vascular permeability in the conscious rat: interactions with platelet-activating factor

1. The objectives of the present experiments were to assess the effects of endothelin-1 on the macrovascular permeability in selected vascular beds, to study the involvement of platelet-activating factor (PAF) in vascular responses to endothelin-1 and to examine the vascular effects of combined administration of endothelin-1 and PAF in conscious rats. 2. Intravenous bolus injection of endothelin-1 (0.1-2 nmol kg-1) resulted in a dose-dependent biphasic change in mean arterial blood pressure (MABP) with initial transient hypotension followed by a prolonged pressor action. These changes were accompanied by a dose-dependent increase in haematocrit values. 3. Endothelin-1 (0.1 and 1 nmol kg-1) increased dose-dependently the vascular permeability of the trachea, upper and lower bronchi, stomach, duodenum, spleen and kidney (up to 240%) as measured by the extravasation of Evans blue dye. The permeability of pulmonary parenchyma, liver and pancreas was not affected significantly by endothelin-1 treatment. 4. Pretreatment of animals with the specific PAF receptor antagonist, WEB 2086 (1 mg kg-1, i.v.) or BN 52021 (10 mg kg-1, i.v.) reduced the endothelin-1 (1 nmol kg-1)-induced rise in haematocrit by about 50 and 30%, respectively. Both antagonists were highly effective at inhibiting protein extravasation in the stomach, duodenum and kidney. On the other hand, BN 52021, but not WEB 2086, significantly attenuated the effect of endothelin-1 on permeability in the lower bronchi and spleen. Neither WEB 2086 nor BN 52021 modified the changes in MABP evoked by endothelin-1.5. When low doses of endothelin-1 (0.1 nmolkg-')and PAF (0.19nmolkg-')were administered simultaneously, enhanced protein extravasation was detected in the upper and lower bronchi, whereas neither endothelin-1 nor PAF by themselves affected vascular permeability in these tissues. These changes occurred in the absence of significant changes in MABP.6. Combined administration of higher doses of endothelin-1 (1nmolkg-') and PAF (1.9nmolkg-') resulted in marked increases (up to 530%) in protein extravasation in the airways, pancreas, stomach and duodenum. The effect of endothelin-1 on permeability was not affected by PAF in the spleen, whereas it was completely inhibited by PAF in the kidney. Combined injection of endothelin-1 and PAF resulted in a slight, but significant increase in MABP.7. The present findings show that endothelin-1 is capable of increasing vascular permeability in selected vascular beds including the airways, gastrointestinal tract and kidney, and suggest that PAF may mediate, in part, its action on permeability, but not its hypotensive action. The present data also suggest that endothelin-1 and PAF can act in concert to increase vascular permeability in rat airways and gastrointestinal tract.

Anti-TIGIT therapies for solid tumors: a systematic review

Programmed death-ligand 1[PD-(L)1], cytotoxic T-lymphocyte associated protein 4 (CTLA-4), and lymphocyte-activation gene 3 (LAG-3) inhibitors are recent breakthroughs in cancer treatment, however not all patients benefit from it. Thus new therapies are under investigation, such as anti-TIGIT [anti-T-cell immunoreceptor with immunoglobulin (Ig) and immunoreceptor tyrosine-based inhibitory motif domains] antibodies. TIGIT is an immune checkpoint inhibiting lymphocyte T cells by several mechanisms. In vitro models showed its inhibition could restore antitumor response. Furthermore, its association with anti-PD-(L)1 therapies could synergistically improve survival. We carried out a review of the clinical trial about TIGIT referenced in the PubMed database, finding three published clinical trials on anti-TIGIT therapies. Vibostolimab was evaluated in a phase I alone or in combination with pembrolizumab. The combination had an objective response rate of 26% in patients with a non-small-cell lung cancer (NSCLC) naïve of anti-programmed cell death protein 1 (anti-PD-1). Etigilimab was tested in a phase I alone or in combination with nivolumab, but the study was stopped due to business reasons. In the phase II CITYSCAPE trial, tiragolumab demonstrated higher objective response rate and progression-free survival in combination with atezolizumab than atezolizumab alone in advanced PD-L1-high NSCLC. The ClinicalTrials.gov database references 70 trials of anti-TIGIT in patients with cancer, 47 of them with ongoing recruitment. Only seven were phase III, including five about patients with NSCLC, mostly with combination therapy. Data from phase I-II trials highlighted that targeting TIGIT represents a safe therapeutic approach, with an acceptable toxicity profile maintained when adding anti-PD-(L)1 antibodies. Frequent adverse events were pruritus, rash, and fatigue. Grade 3-4 adverse events were reported in nearly one in three patients. Anti-TIGIT antibodies are under development as a novel immunotherapy approach. A promising research area includes the combination with anti-PD-1 therapies in advanced NSCLCs.

Assessing viability and infectivity of foodborne and waterborne stages (cysts/oocysts) of Giardia duodenalis, Cryptosporidium spp., and Toxoplasma gondii: a review of methods

Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii are protozoan parasites that have been highlighted as emerging foodborne pathogens by the Food and Agriculture Organization of the United Nations and the World Health Organization. According to the European Food Safety Authority, 4786 foodborne and waterborne outbreaks were reported in Europe in 2016, of which 0.4% were attributed to parasites including Cryptosporidium, Giardia and Trichinella. Until 2016, no standardized methods were available to detect Giardia, Cryptosporidium and Toxoplasma (oo)cysts in food. Therefore, no regulation exists regarding these biohazards. Nevertheless, considering their low infective dose, ingestion of foodstuffs contaminated by low quantities of these three parasites can lead to human infection. To evaluate the risk of protozoan parasites in food, efforts must be made towards exposure assessment to estimate the contamination along the food chain, from raw products to consumers. This requires determining: (i) the occurrence of infective protozoan (oo)cysts in foods, and (ii) the efficacy of control measures to eliminate this contamination. In order to conduct such assessments, methods for identification of viable (i.e. live) and infective parasites are required. This review describes the methods currently available to evaluate infectivity and viability of G. duodenalis cysts, Cryptosporidium spp. and T. gondii oocysts, and their potential for application in exposure assessment to determine the presence of the infective protozoa and/or to characterize the efficacy of control measures. Advantages and limits of each method are highlighted and an analytical strategy is proposed to assess exposure to these protozoa.

Population pharmacokinetic modeling of oral cyclosporin using NONMEM: comparison of absorption pharmacokinetic models and design of a Bayesian estimator

There have been very few population pharmacokinetic (PopPK) studies and Bayesian forecasting methods dealing with cyclosporin (CsA) so far, probably because of the difficulty of modeling the particular absorption profiles of CsA. The present study was conducted in stable renal transplant patients treated with Neoral and employed the NONMEM program. Its goals were (1) to develop a population pharmacokinetic model for CsA based on an Erlang frequency distribution (which describes asymmetric S-shaped absorption profiles) combined with a 2-compartment model; (2) to compare this model with models combining a time-lag parameter and either a zero-order or first-order rate constant and with a model based on a Weibull distribution; and (3) to develop a PK Bayesian estimator for full AUC estimation based on that "Erlang model." The PopPK model was developed in an index set of 70 patients, and then individual PK parameters and AUC were estimated in 10 other patients using Bayesian estimation. The "Erlang" model best described the data, with mean absorption time (MAT), apparent clearance (CL/F), and apparent volume of the central compartment (Vc/F) of 0.78 hours, 26.3 L/h, and 76 L, respectively (interindividual variability CV = 33, 30, and 48%). Bayesian estimation allowed accurate prediction of systemic exposure using only 3 samples collected at 0, 1, and 3 hours. Regression analysis found no significant difference between the predicted and observed concentrations (10 per patient), and AUC(0-12) were estimated with a nonsignificant bias (0.6 to 8.7%) and good precision (RMSE = 5.3%). In conclusion, the Erlang distribution best described CsA absorption profiles, and a Bayesian estimator developed using this model and a mixed-effect PK modeling program provided accurate estimates of CsA systemic exposure using only 3 blood samples.

Acute hyperoxaemia-induced effects on regional blood flow, oxygen consumption and central circulation in man

AIM

Despite numerous in vitro and animal studies, circulatory effects and mechanisms responsible for the vasoconstriction seen during hyperoxaemia are yet to be ascertained. The present study set out to: (i) set up a non-invasive human model for the study of hyperoxia-induced cardiovascular effects, (ii) describe the dynamics of this effect and (iii) determine whether hyperoxaemia also, by vasoconstriction alters oxygen consumption (O(2)).

METHODS

The study comprised four experiments (A, B, C and D) on healthy volunteers examined before, during and after 100% oxygen breathing. A: Blood flow (mL min(-1).100 mL(-1) tissue), venous occlusion plethysmography was assessed (n = 12). B: Blood flow was recorded with increasing transcutaneous oxygen tension (P(tc)O(2)) levels (dose-response) (n = 8). C: Heart rate (HR), stroke volume, cardiac output (CO) and systemic vascular resistance (SVR) was assessed using echocardiography (n = 8). D: O(2) was measured using an open circuit technique when breathing an air-O(2) mix (fraction of inhaled oxygen: F(i)O(2) = 0.58) (n = 8).

RESULTS

Calf blood flow decreased 30% during O(2) breathing. The decrease in calf blood flow was found to be oxygen dose dependent. A similar magnitude, as for the peripheral circulation, of the effect on central parameters (HR/CO and SVR) and in the time relationship was noted. Hyperoxia did not change O(2). An average of 207 (93) mL O(2) per subject was washed in during the experiments.

CONCLUSION

This model appears suitable for the investigation of O(2)-related effects on the central and peripheral circulation in man. Our findings, based on a more comprehensive (central/peripheral circulation examination) evaluation than earlier made, suggest significant circulatory effects of hyperoxia. Further studies are warranted to elucidate the underlying mechanisms.

[Validation of the French version of the Body Shape Questionnaire]

In today's societies, pressures from the idea of thinness are omnipresent and lead to a corporal dissatisfaction with an excessive preoccupation of the body's image. It seems important to have, in France, a device that can evaluate the corporal dissatisfaction degree, for the reason that the troubles of the body's image is a common diagnostical category to the anorexia and bulimia (DSM IV, 1994). Cooper et al. (1987) have developed one-dimensional questionnaire of 34 items in order to measure the worries towards the weight and the shape of the body, called the "Body Shape Questionnaire" (BSQ). Its concurrent validity has been shown with the using of the corporal dissatisfaction under-scale of the Eating Disorders Inventory (EDI; Garner et Olmsted, 1984) and the using of the diagnostical questionnaire: Eating Attitude Test (EAT; Garner et Garfinkel, 1979). The BSQ gives us a way to explore the role of extreme worries towards the body's apparence in the development, the keeping and the treatment of eating disorders. From this point the BSQ is a tool widely used on an international level in researches on the eating disorders. It has been validited in Spain and in Germany whereas it has not been yet subject to a validation in France. For this reason, we proposed to use the BSQ on the french population.

METHODOLOGY

The sample is made of 242 university girl students. The average age is 20.7 years old with an standard deviation of 2.26. The size and the weight helped us to calculate the Body Mass Index (BMI) which is in fact the weight divided by the size squared. The average BMI is 21.06 kg/m2 +/- 2.87. Regarding the evaluating devices, the BSQ is presented as a scale of 34 items marked by 6 different points: 1 never, 2 barely, 3 sometimes, 4 often, 5 very often, 6 always. After getting the authorization form the authors to respect during these kinds of procedures, we have started validation. The corporal dissatisfaction under-scale of Eating Disorder Inventory (EDI, Garner et al., 1991) is made of 9 items and has a scale of 6 points going from "never" to "always". In order to evaluate the accuracy of the Body Shape Questionnaire (BSQ) in France, we made a test/retest. The concurrent validity of the BSQ has been evaluated by the EDI. The 242 subjects have been asked to fill in both questionnaires during the test and the re-test (4 weeks after the test). We have evaluated the accuracy of the BSQ with the calculation of the constancy test/retest (Pearson's r) and the measure of the internal consistency (Cronbach's alpha). Then, we tested the validity regarding an external criteria. The validation procedure is based here on an examination of the correlations between the tests results (BSQ) and another measure taken as criteria (EDI). The solutions proposed by the factorial exploratory analysis have been tested by confirmatory analysis using the 2 index of adjustment: the GFI ("Goodness of Fit Index") and the CFI (Comparative Index of Bentler) which, greater than 0.85, shows a satisfying adjustment and the RMC (redidue) which has to be less than 0.10 for a satisfying adjustment. Finally, inferential statistical analysis have studied the relations between the weight's category and the total result at the BSQ and the results of the factors sprung from factorial analysis.

RESULTS

Correlations between the items of test/re-test BSQ are greater than 0.93. The alpha coefficient is high for the test (0.95) and also for the re-test (0.94). This shows a very good internal consistency between the 34 items of the BSQ. Concerning the EDI, the correlation between the test/re-test are greater than 0.98. The alpha coefficient of Cronbach is high: 0.85 for the test and 0.84 for the re-test. The Pearson's r of the BSQ/EDI test and the BSQ/EDI re-test greater than 0.7 point out the concomitant validity of the BSQ with the EDI. We made a factorial analysis of the BSQ (test) on the 242 subjects. We used the extraction of the main components method with the extraction's rule of the curve for the real values. The transformation method used here is the normalised Varimax. The factorial analysis shows four factors with their own value greater or equal to 1 (15.1; 1.77; 1.48; 1.08). This solution concerning these four factors explains 55.2% of the total variance. The oblical rotations analysis of the four factors seems to point out a high correlation between these latters (from 0.54 to 0.77), this suggests a hierarchical pattern with a single factor which is confirmed with an Cronbach's alpha of 0.95. Then, we chose to gather around each selected factors the items presenting a substantial saturation, greater than or equal to 0.5 and which are saturated by only one factor. The first factor obtained by the factorial analysis of the BSQ has been called "social avoidance and shame of the exposure of the body". The internal coherence of this factor is satisfactory (Cronbach's alpha = 0.87). The second factor obtained has been called "body dissatisfaction compared to the lower parts ot the body (Cronbach's alpha = 0.90). The third factor has been called "using laxatives and vomiting in order to reduce body dissatisfaction" The fourth factor has been called "unsuited cognitions and behaviours in order to control the weight (Cronbach's alpha = 0.76). The solution with 1 and 4 factors has been tested by a confirmatory analysis. The adjustment parameters of the unifactorial pattern were not satisfactory (GFI = 0.76, CFI = 0.83, RMC = 0.5). The 4 factors pattern adjusted better to the data (GFI = 0.86, CFI = 0.90, RMC = 0.5). In order to determinate the differences between the weight/score categories to the BSQ) score in comparison to the 4 factors (coming from the factorial analysis), several Anova have been released as well as post-hoc tests (test of Sheffé). There is a significant effect of the weight category on the corporal dissatisfaction (BSQ result), F (2.230) = 11.34; p < 0.0001. Scheffe's test placed in a prominent position the fact that the subjects having an overweight (99.85 +/- 31.34) have a corporal dissatisfaction significantly greater than the subjects having a normal weight (74.08 +/- 27.94) and presenting a thinness (63.19 +/- 23.61). We pointed out a significant effect of the weight category on factor one "social avoidance and shame of the exposure of the body" [F (2.232) = 20.18; p < 0.001], on factor 2 "body dissatisfaction compared to the lower parts of the body" [F (2.232) = 6.38; p < 0.005] and factor 4 "reduce body dissatisfaction and unsuited cognitions and behaviours in order to control the weight" [F (2.232) = 5.67; p < 0.005]. However, there is no effect in the weight category for factor 3 "using laxatives and cominting in order to reduce the corporal dissatisfaction" [F (2.232) = 5.67; p > 0.05]. Sheffe's test highlighted the fact that the subjects having overweight have a result more important than the ones having a normal weight and presenting a thinness for factor 1.2 and 4.

DISCUSSION

The BSQ "French version" seems in fact to present the same metrical qualities than its original Anglo-Saxon and Spanish versions. The concluding results invite us to continue our study of the BSQ including in our patients, the bulimic subjects and the ones who are worried about corporal aspect. Its implications on the clinical field could be really interesting especially on people suffering from the eating disorders. Then, the BSQ could provide us a way to explore the role of an extreme worry of the body's appearance in the development, the maintenance and the treatment of the eating disorders.

Human cardiovascular dose-response to supplemental oxygen

AIM

The aim of the study was to examine the central and peripheral cardiovascular adaptation and its coupling during increasing levels of hyperoxaemia. We hypothesized a dose-related effect of hyperoxaemia on left ventricular performance and the vascular properties of the arterial tree.

METHODS

Oscillometrically calibrated arterial subclavian pulse trace data were combined with echocardiographic recordings to obtain non-invasive estimates of left ventricular volumes, aortic root pressure and flow data. For complementary vascular parameters and control purposes whole-body impedance cardiography was applied. In nine (seven males) supine, resting healthy volunteers, aged 23-48 years, data was collected after 15 min of air breathing and at increasing transcutaneous oxygen tensions (20, 40 and 60 kPa), accomplished by a two group, random order and blinded hyperoxemic protocol.

RESULTS

Left ventricular stroke volume [86 +/- 13 to 75 +/- 9 mL (mean +/- SD)] and end-diastolic area (19.3 +/- 4.4 to 16.8 +/- 4.3 cm(2)) declined (P < 0.05), and showed a linear, negative dose-response relationship to increasing arterial oxygen levels in a regression model. Peripheral resistance and characteristic impedance increased in a similar manner. Heart rate, left ventricular fractional area change, end-systolic area, mean arterial pressure, arterial compliance or carbon dioxide levels did not change.

CONCLUSION

There is a linear dose-response relationship between arterial oxygen and cardiovascular parameters when the systemic oxygen tension increases above normal. A direct effect of supplemental oxygen on the vessels may therefore not be excluded. Proximal aortic and peripheral resistance increases from hyperoxaemia, but a decrease of venous return implies extra cardiac blood-pooling and compensatory relaxation of the capacitance vessels.

Enhancement by endothelin-1 of microvascular permeability via the activation of ETA receptors

1. The objective of the present experiments was to assess the involvement of endothelin-A (ETA) receptors in mediating the effects of endothelin-1 on microvascular permeability in conscious rats. 2. Bolus injection of endothelin-1 (0.1 and 1 nmol kg-1, i.v.) resulted in a dose-dependent prolonged pressor effect preceded by a transient depressor response. These changes were accompanied by a dose-dependent loss of plasma volume. Endothelin-1 (1 nmol kg-1) enhanced the vascular permeability of the upper and lower bronchi, kidney, stomach, duodenum and spleen (up to 270%) as measured by the extravasation of Evans blue dye. 3. Pretreatment of the animals with the selective ETA receptor antagonist, BQ-123 (1 mg kg-1, i.v.) significantly blunted the pressor response to endothelin-1 without affecting the depressor response. BQ-123 inhibited by 87% the endothelin-1 (1 nmol kg-1)-induced plasma volume loss. BQ-123 markedly attenuated protein extravasation elicited by endothelin-1 in the upper and lower bronchi and kidney, whereas it completely inhibited the permeability effect of endothelin-1 in the stomach and duodenum. BQ-123 by itself had no significant effect on the parameters studied. 4. The endothelin-1 analogue, [Trp(For)21]-endothelin-1, in which Trp21 is formylated, was as potent a pressor agent as endothelin-1, but had no depressor action. Bolus injection of [Trp(For)21]-endothelin-1 (0.1 and 1 nmol kg-1, i.v.) evoked similar plasma volume losses to those observed following administration of equimolar doses of endothelin-1. Furthermore, 1 nmol kg-1 [Trp(For)21]-endothelin-l evoked increases in protein extravasation similar to endothelin-l, 1 nmol kg-1.5. The present findings suggest that endothelin- 1 enhances microvascular permeability, in part, via the activation of ETA receptors.

Donor P-gp polymorphisms strongly influence renal function and graft loss in a cohort of renal transplant recipients on cyclosporine therapy in a long-term follow-up

Cyclosporin A (CsA) is a substrate for cytochrome P450 3A and the efflux transporter P-glycoprotein (P-gp; ABCB1), both abundantly expressed in the kidney. In a long-term follow-up of a cohort of patients who had received kidney transplants between the years 1990 and 2005, we retrospectively investigated the effect of CYP3A4, CYP3A5, and ABCB1 polymorphisms in kidney graft donors on recipients' renal function and risk of subsequent graft loss. DNA samples from 227 donors and clinical data from the 259 respective recipients were analyzed. Graft loss was significantly associated with the presence of the ABCB1 variant haplotype 1236T/2677T/3435T in the donor (1236T/2677T/3435T vs. other haplotypes: hazard ratio = 9.346; 95% confidence interval (CI) (2.278-38.461); P = 0.0019) and with previous episodes of acute organ rejection (hazard ratio = 3.077; 95% CI (1.213-7.812); P = 0.0178). The variant haplotype was also associated with a greater decrease in renal function (homozygotes for TTT -3.047 mlxmin(-1)/year; heterozygotes for TTT -4.435 mlxmin(-1)/year; others -2.186 mlxmin(-1)/year; P = 0.0240). The study showed that the presence of ABCB1 polymorphisms in donors influences long-term graft outcome adversely with decrease in renal function and graft loss in transplant recipients receiving CsA.

Promoting lentil germination and stem growth by plasma activated tap water, demineralized water and liquid fertilizer

Tap water, demineralized water and liquid fertilizer have been activated using an atmospheric pressure plasma jet (APPJ) to investigate their benefits for the germination rate and stem elongation rate of lentils from Puy-en-Velay (France).

Vascular responses to endothelin-1 following inhibition of nitric oxide synthesis in the conscious rat

1. The objectives of the present experiments were to assess the role of endogenous nitric oxide (NO) in mediating and/or modulating the effects of endothelin-1 (ET-1) on blood pressure and microvascular permeability in conscious rats. 2. Intravenous administration of the NO synthesis inhibitors, NG-monomethyl-L-arginine (L-NMMA) or NG-nitro-L-arginine methyl ester (L-NAME) at a dose (25 mg kg-1 or 2 mg kg-1, respectively) which evoked maximum increase in mean arterial blood pressure (MABP) significantly attenuated (by about 40%) the vasodepressor response and potentiated (by 100-180%) the pressor response to ET-1 (1 nmol kg-1, i.v.) compared to the effects of ET-1 in animals where the peripheral vasoconstrictor effects of L-arginine analogues were mimicked by an infusion of noradrenaline (620-820 ng kg-1 min-1). Similar inhibition of the depressor and potentiation of the pressor actions of ET-1 were observed when the MABP which had been elevated by L-NMMA or L-NAME was titrated to normotensive levels with hydralazine or diazoxide before injection of ET-1. 3. L-NAME (2 mg kg-1) increased the vascular permeability of the large airways, stomach, duodenum, pancreas, liver, kidney and spleen (up to 280%) as measured by the extravasation of Evans blue dye. The permeability of pulmonary parenchyma, skeletal muscle and skin was not affected significantly by L-NAME treatment. Elevation of MABP by noradrenaline infusion did not evoke protein extravasation in the vascular beds studied with the exception of the lung. In the large airways, tissue Evans blue content was similar following noradrenaline infusion and L-NAME.4. Both the pressor and permeability effects of L-NAME (2 mg kg-1) were effectively reversed by L-arginine (300 mg kg- 1) but not by D-arginine (300 mg kg-1 ). The D-enantiomer of L-NAME, D-NAME(2 mg kg-1) had no effect on the parameters studied.5. Protein extravasation was significantly enhanced by ET-1 (1 nmol kg-1) in the upper and lower bronchi, stomach, duodenum, kidney and spleen (up to 285%). This was potentiated by L-NAME(2 mg kg-1), resulting in marked increases in tissue Evans blue accumulation (up to 550%) in these tissues. The effects of L-NAME and ET-1 were additive in the trachea, duodenum, pancreas and liver.Combined administration of L-NAME plus ET-1 significantly increased protein extravasation in the pulmonary parenchyma, where neither L-NAME nor ET-1 alone caused significant increases.6. Noradrenaline infusion (620-820 ng kg-1 min-1) potentiated the permeability action of ET-1(1 nmol kg-1) in the pulmonary circulation, whereas it did not modify ET-1-induced protein extravasation in the other vascular beds.7. These results indicate that endogenous NO mediates, in part, the vasodepressor effect and attenuates the vasopressor action of ET-1 and modulates the effects of ET-1 on vascular permeability. These findings confirm the role of NO in the maintenance of blood pressure and suggest an important role for NO in the regulation of microvascular permeability.

Frequent cyclin D1 gene amplification and protein overexpression in oral epithelial dysplasias

Amplification of the cyclin D1 gene has been identified in 17-55% of head and neck squamous cell carcinoma. In some tumors, this alteration has been associated with decreased survival and increased recurrence rates. In precancerous lesions of the mouth, the frequency of cyclin D1 gene amplification is not known. In addition, it is unknown whether amplification of the gene translates to overexpressed cyclin D1 protein in these lesions. We examined 59 formalin-fixed, paraffin embedded tissue biopsies of oral epithelial dysplasias (OED) and 25 oral squamous cell carcinoma (SCC) from the floor of the mouth for cyclin D1 gene and protein levels. Genomic DNA was extracted from laser microdissected lesional tissue and a duplex, quantitative PCR assay was used to determine the amplification of the cyclin D1 gene relative to interferon-gamma. Cyclin D1 protein expression was determined using immunohistochemistry and counting positive nuclei by computer image analysis. We found cyclin D1 gene amplification in 41% of mild, 45% of moderate and 24% of severe OEDs. Cyclin D1 was amplified in 36% of SCC. Overexpression of cyclin D1 protein was identified in 29% of mild, 47% of moderate, 29% of severe OED's, and in 32% of SCC. Overexpression of cyclin D1 protein was identified in similar proportions of all grades of dysplasia and SCC. There were statistically significant correlations identified between gene and protein levels in all categories of disease. We concluded that amplification of the cyclin D1 gene is frequent in OED and that duplex, quantitative polymerase chain reaction is a reliable method to detect this change in routinely processed biopsies. The strong correlation between cyclin D1 gene amplification and protein levels suggests that this method may be suitable to assess cyclin D1 gene status in tissues not suitable for protein analysis.

T cell response to Hu-D peptides in patients with anti-Hu syndrome

The anti-Hu syndrome is the most common paraneoplastic neurologic syndrome but the exact mechanism of immune mediated neuronal injury remains unknown. Anti-Hu antibodies do not appear to play a pivotal role in the pathogenesis of the disease. To assess cell-mediated immunity, we selected 51 peptides from the Hu-D sequence and tested their ability to bind to six common HLA class I molecules. Stable complexes with purified HLA molecules were obtained with 19/51 (37%) selected peptides. Subsequently, the ability of the 19 HLA-binding peptides to stimulate T cells from 10 patients and 10 control subjects was evaluated by detecting IFN-gamma secretion. An anti-peptide T-cell response was observed in 7/10 Hu-positive patients but also in 3/10 control subjects. Overall, a significant T-cell activation occurred in response to 74% (14 out of 19) of the selected peptides in the Hu-positive patients vs. 16% (3 out of 19) in the control group (p < 0.001). In addition, T cells of patients tested within 3 months of the onset of anti-Hu syndrome responded to 82% (14 out of 17) of assessed Hu-D peptides vs. 37% (7 out of 19) in patients tested 1 year or more after developing the syndrome (p < 0.01). Thus, the present study suggests a role of cellular immunity during the course of anti-Hu syndrome.

Practical way to assess metabolic syndrome using a continuous score obtained from principal components analysis

AIMS/HYPOTHESIS

We devised a practical continuous score to assess the metabolic syndrome, and assessed whether this syndrome score predicts incident diabetes and cardiovascular disease.

SUBJECTS AND METHODS

Among 5,024 participants of the Data from an Epidemiological Study on the Insulin Resistance Syndrome (D.E.S.I.R.) cohort, we defined a metabolic syndrome score by the first principal component (PC1), using only the correlations between continuous metabolic syndrome measures (glucose, waist circumference, triglycerides, and systolic blood pressure). This metabolic syndrome score was highly correlated with a similar score also including insulin and HDL cholesterol (r ( s )=0.94). Over 9 years of follow-up, incident diabetes and cardiovascular disease (CVD) were predicted by logistic regression using the simpler metabolic syndrome score.

RESULTS

The means of the metabolic syndrome measures differed between men and women. Nevertheless, as the degree of variance explained and the PC1 coefficients were remarkably similar, we used a common metabolic syndrome score. The metabolic syndrome score explained 50% of the variance of the metabolic syndrome measures, and waist circumference had the highest correlation (0.59) with this score. Each standard deviation increase in the metabolic syndrome score was associated with a markedly increased age-adjusted risk of developing diabetes (odds ratios: men 3.4 [95% CI 2.6-4.4]; women 5.1 [3.6-7.2]) and with increased incident CVD of 1.7 (1.4-2.1) in men and 1.7 (1.0-2.7) in women.

CONCLUSIONS/INTERPRETATION

Our results, which should be confirmed in other populations, suggest that it is possible to evaluate the risk of the metabolic syndrome in a pragmatic fashion with a continuous score, obtained from principal components analysis of the basic, continuous syndrome measures.

Serum and cerebrospinal fluid concentrations of melatonin: a pilot study in healthy male volunteers

Melatonin was determined in serum and cerebrospinal fluid (CSF) obtained from 13 healthy males lumbar-punctured in the sitting position without preceding bed rest. There was a significant correlation between the levels of melatonin in serum and the CSF. The serum concentration was lower than that in the CSF, a finding that calls in question the theory that melatonin is mainly released from the pineal gland into the bloodstream. In conclusion, serum levels of melatonin in healthy male volunteers, mirror the CSF concentrations when lumbar puncture is carried out using the described technique.

Primary intracranial myopericytoma: report of three cases and review of the literature

Myopericytoma is a benign tumour generally arising in the subcutaneous and superficial soft tissues of the extremities. Very few cases have been reported in other locations and intracranial examples are exceptional. We now report on three cases of primary intracranial myopericytoma and review the literature on that rare entity. The patients were women in their fifties who presented with decreased visual acuity in two cases and raised intracranial pressure in one case. The tumour involved, respectively, the anterior cranial fossa, the orbital apex and the pineal region. Gross total resection was achieved in all three cases. Histological analysis revealed oval-to-spindle shaped myoid-appearing cells with a striking tendency for concentric perivascular growth. The lesional cells showed apparent differentiation towards perivascular myoid cells as witnessed by smooth muscle actin expression. In one case, an epithelioid differentiation was also present. None of the patients received adjuvant therapy. One patient died of unrelated causes 6 months after surgery. The other two are alive and well at 9 and 12 month follow-up respectively. Myopericytoma is a recently described neoplasm, and it is likely that reappraisal of intracranial haemangiopericytoma with which it shares many histopathologic features will lead to more case reports of primary intracranial myopericytoma.

Canthaxanthin retinopathy. Anatomic and functional reversibility

Canthaxanthin intake is associated with golden yellow crystalline deposits in the retina around the macula and low static luminance threshold. Our study assesses the anatomic and functional reversibility of canthaxanthin retinopathy. The number of retinal deposits was evaluated in nine patients, two to four times over a mean period of 55 months. There was no significant difference after a nine-month follow-up. A statistically significant decrease in the number of retinal deposits was found after an observation period of 26 months. The deposits disappeared slowly, while some remained even seven years after canthaxanthin therapy was discontinued. Threshold static perimetry performed on eight patients with retinopathy and seven controls did not differ significantly between the two groups at the end of the follow-up period. The results demonstrate that canthaxanthin retinopathy is reversible.