Synthesis, binding affinity at glutamic acid receptors, neuroprotective effects, and molecular modeling investigation of novel dihydroisoxazole amino acids

The four stereoisomers of 5-(2-amino-2-carboxyethyl)-4,5-dihydroisoxazole-3-carboxylic acid(+)-4, (-)-4, (+)-5, and (-)-5 were prepared by stereoselective synthesis of two pairs of enantiomers, which were subsequently resolved by enzymatic procedures. These four stereoisomers and the four stereoisomers of the bicyclic analogue 5-amino-4,5,6,6a-tetrahydro-3aH-cyclopenta[d]isoxazole-3,5-dicarboxylic acid (+)-2, (-)-2, (+)-3, and (-)-3 were tested at ionotropic and metabotropic glutamate receptor subtypes. The most potent NMDA receptor antagonists [(+)-2, (-)-4, and (+)-5] showed a significant neuroprotective effect when tested in an oxygen glucose deprivation (OGD) cell culture test. The same compounds were preliminarily assayed using Xenopus oocytes expressing cloned rat NMDA receptors containing the NR1 subunit in combination with either NR2A, NR2B, NR2C, or NR2D subunit. In this assay, all three derivatives showed high antagonist potency with preference for the NR2A and NR2B subtypes, with derivative (-)-4 behaving as the most potent antagonist. The biological data are discussed on the basis of homology models reported in the literature for NMDA receptors and mGluRs.     

Sex-hormone receptors pattern on regulatory T-cells: clinical implications for multiple sclerosis

Cellular mechanisms underlying sexual dimorphism in the immune response remain largely unknown. Concerning the interactions among the nervous, endocrine and immune systems, we reported that during gestation, a period during which multiple sclerosis (MS) clearly ameliorates, there is a physiological expansion of regulatory T-lymphocytes (T(Reg)). Given that alterations in T(Reg) proportions and suppressive function are involved in MS pathophysiology, we investigated the in vitro effect of sex hormones on T(Reg). Here, we show that both E2 and progesterone (P2) enhance T(Reg) function in vitro, although only E2 further induces a T(Reg) phenotype in activated responder T-cells (CD4(+)CD25(-)) (P < 0.01). E2 receptor beta (ERβ) percentages and mean fluorescence intensity (MFI) on T(Reg) were lower in MS patients than in controls (P < 0.05), in parallel with lower E2 plasma levels (P < 0.05). Importantly, percentages and MFI of ERβ were higher in T(Reg) than in T-responder cells (P < 0.0001) both in MS patients and controls. We show a unique differential pattern of higher ER and PR levels in T(Reg), which may be relevant for the in vivo responsiveness of these cells to sex hormones and hence to MS physiopathology.     

Proton pump inhibitor treatment of patients with gastroesophageal reflux-related chronic cough： A comparison between two different daily doses of lansoprazole

AIM:To compare two different daily doses oflansoprazole given for 12 weeks and to assess the roleof gastrointestinal (GI) investigations as criteria forselecting patients.METHODS:Out of 45 patients referred for unexplainedchronic persistent cough,36 had at least one of theGI investigations (endoscopy,24-h esophageal pH-metry and a 4-week trial of proton pump inhibitor (PPI)therapy) positive and were randomly assigned to receiveeither 30 mg lansoprazole o.d.or 30 mg lansoprazoleb.i.d,for 12 weeks.Symptoms were evaluated atbaseline (visit 1) after the PPI test (visit 2) and after the12-week lansoprazole treatment period (visit 3).RESULTS:Thirty-five patients completed the studyprotocol.Twenty-one patients (60.0%) reportedcomplete relief from their cough with no differencebetween the two treatment groups (58.8% and 61.1%had no cough in 30 mg lansoprazole and 60 mglansoprazole groups,respectively).More than 80% ofthe patients who had complete relief from their cough atthe end of the treatment showed a positive response tothe PPI test.CONCLUSION:Twelve weeks of lansoprazole treatmenteven at a standard daily dose,is effective in patientswith chronic persistent cough.A positive response to aninitial PPI test seems to be the best criterion for selectingpatients who respond to therapy.     

Time course of early metabolic changes following diffuse traumatic brain injury in rats as detected by (1)H NMR spectroscopy

Experimental models of traumatic brain injury (TBI) provide a useful tool for understanding the cerebral metabolic changes induced by this pathological condition. Here, we report on the time course of changes in cerebral metabolites after TBI and its correlation with early brain morphological changes using a combination of high-resolution proton magnetic resonance spectroscopy ((1)H MRS) and magnetic resonance imaging (MRI). Adult male Sprague-Dawley rats were subjected to closed head impact and examined by MRI at 1, 9, 24, 48, and and 72 h after the injury. Extracts from funnel frozen rat brains were then obtained and analyzed quantitatively by high-resolution (1)H MRS. Finally, statistical multivariate analysis was carried out to identify the combination of cerebral metabolites that best described the time evolution of diffuse TBI. The temporal changes observed in the concentration of cerebral metabolites followed three different patterns. The first pattern included taurine, threonine, and glycine, with concentrations peaking 24 h after the injury. The second pattern included glutamate, GABA, and alanine, with concentrations remaining elevated between 24 and 48 h post-injury. The third one involved creatine-phosphocreatine, N-acetylaspartate, and myo-inositol, with concentrations peaking 48 h after the injury. A multivariate stepwise discriminant analysis revealed that the combination of the organic osmolytes taurine and myo-inositol allowed optimal discrimination among the different time groups. Our findings suggest that the profile of some specific brain molecules that play a role as organic osmolytes can be used to follow-up the progression of the early diffuse brain edema response induced by TBI.     

Molecular adsorbent recirculating system (MARS) application in liver failure: clinical and hemodepurative results in 22 patients

PURPOSE: Acute liver failure (ALF) and acute on chronic liver failure (ACLF) still show a poor prognosis. MARS was used in 22 patients with ALF or ACLF to prolong patient survival for liver function recovery or as a bridge to transplantation. DESIGN: Evaluation of depurative efficiency, biocompatibility, hemodynamics, encephalopathy (HE) and clinical outcome. PROCEDURES: During 71 five-hour sessions we evaluated (0', 60', 120', 180', 240', 300'): bilirubin, ammonia, cholic acid (CCA), chenodeoxycholic acid (CCDCA), leukocytes, platelets, hemoglobin and mean arterial pressure (MAP). Serum creatinine, electrolytes, cardiac output, cardiac index (bioimpedence) and HE (West Haven Criteria score) were evaluated at 0' and 300'. STATISTICAL METHODS AND OUTCOME MEASURES: Student's t-test for pre- vs. end-session values was used. For bilirubin and ammonia the correlation test was made between pre- and end-session values and between pre-session values and removal rates (RRS). MAIN FINDINGS: Survival was 90.9% at 7 days, 40.9% at 30 days. Pre- vs. end-session: bilirubin from 37.2 +/- 12.5 mg/dL to 24.9 +/- 8.9 mg/dL (p < 0.01), ammonia from 88.0 +/- 60.4 micromol/L to 43.6 +/- 32.9 micromol/L (p < 0.01), CCA from 42.8 +/- 21.0 micromol/L 18.2 +/- 9.8 micromol/L (p < 0.01), CCDCA from 26.3 +/- 6.3 micromol/L to 15.7+/-7.6 micromol/L (p<0.01). The correlation test between pre-session values of bilirubin and ammonia vs. RR S was respectively 0.32 (p = 0.01) and 0.30 (p = 0.04). Leukocytes, platelets and hemoglobin remained stable. MAP increased from 82.0 +/- 12.0 mmHg to 87.0 +/- 13.0 mmHg (p < 0.05), West Haven Criteria score decreased from 2.7 +/- 0.7 to 0.7 +/- 0.7 (p < 0.001). CONCLUSION: MARS treatment led in all patients to an improvement of clinical, hemodynamic and neurological conditions, with significant reduction in the hepatic toxins blood level. Treatment biocompatibility and tolerance were satisfactory.     

Is it possible to predict the clinical course of gallstone disease? Usefulness of gallbladder motility evaluation in a clinical setting

OBJECTIVE: A knowledge of the predictive factors of the development and persistence of symptoms in gallstone patients (GS) plays a key role in clinical decision making. The aim of this study was to evaluate the presence of predictive factors for biliary pain development in GS, stressing the role of gallbladder motility. METHODS: A total of 153 (104 women, 49 men) consecutive GS were enrolled. Gallbladder motility (%Emptying [%E], residual volume [RV]) was evaluated by ultrasonography and biliary symptoms were evaluated using a specific questionnaire in all GS at baseline and after 4 yr of follow-up. RESULTS: At enrolment, 61 GS reported recent (GSr) and 31 GS remote (GSo) (>2 yr before) episodes of biliary pain, and 61 were asymptomatic (GSa). At baseline, GSr showed a greater %E and a smaller RV than both GSo and GSa (p < 0.001). After follow-up, biliary pain developed more frequently in GSr (33.3%) than in GSo (16%) and GSa (15%) (p= 0.04). The search for predictive factors of biliary pain development (by univariate and multivariate analyses) revealed a high %E, a small RV, and a history of biliary pain as risk factors. CONCLUSIONS: Efficient gallbladder motility is present in symptomatic GS and it represents a risk factor for biliary pain development while sluggish motility seems to play a protective role. Thus, gallbladder motility evaluation is a useful diagnostic tool in clinical decision making for GS; in symptomatic GS, a progressive reduction of gallbladder motility could suggest a "wait and see" management policy instead of an immediate surgical approach.     

Formaldehyde exposure and lower respiratory infections in infants: findings from the PARIS cohort study

Background: Certain chemical pollutants can exacerbate lower respiratory tract infections (LRIs), a common childhood ailment. Although formaldehyde (FA) is one of the most common air pollutants found in indoor environments, its impact on infant health is uncertain.Objective: Our aim was to determine the impact of FA exposure on the LRI incidence during the first year of life of infants from the Pollution and Asthma Risk: an Infant Study (PARIS) birth cohort.Methods: FA was measured in a random sample of 196 infants’ dwellings, and exposure to this pollutant was estimated for 2,940 infants using predictive models based on measurements and data about potential determinants of FA levels. Health data were collected from parents by regular self-administered questionnaires. We used multivariate logistic regressions to estimate associations between FA exposure and the occurrence of LRI and wheezy LRI (wLRI), adjusting for potential confounders/risk factors.Results: During the first year of life, 45.8% of infants had at least one LRI, and LRI occurred simultaneously with wheezing in 48.7% of cases. The FA predictive models correctly classified 70% of dwellings as having high or low exposure, and we estimated that 43.3% of infants were exposed throughout the first year to levels of FA > 19.5 µg/m³. FA exposure was significantly associated with LRI and wLRI before and after adjustment for known LRI risk factors/confounders. For an interquartile increase in FA levels (12.4 μg/m³), we estimated a 32% [95% confidence interval (CI): 11, 55] and 41% (95% CI: 14, 74) increase in the incidence of LRI and wLRI, respectively.Conclusion: The findings of this study suggest that infants exposed to FA at an early age have an increased incidence of LRI.