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A Valentin

Publications and source records attributed to A Valentin.

At least 37 records · Page 2Linked to original sources
PubMed2000

New potential antimalarial agents: synthesis and biological activities of original diaza-analogs of phenanthrene.

Several diaza-analogs of phenanthrene derived from 3-amino, 5-amino, 6-amino, 8-aminoquinolines, and 5-aminoisoquinoline were prepared to evaluate their antiplasmodial activities. All compounds showed mild to good activitiy in vitro, both on a Nigerian chloroquino-sensitive strain and on the chloroquino-resistant FcB1-Columbia and FcM29 strains. The position of the intracyclic nitrogen atom is shown to be crucial for the activities (best results are obtained with a 1,10-phenanthroline skeleton). In regard to the particular properties of this structure (metalloprotease inhibition activitiy by chelating divalent metal ions), the potential chelating site of the molecule was blocked. In this case, the biological activity of the compound was greatly enhanced, showing that the mechanism of action of such a compound is probably not correlated to metalloprotease inhibition activity.

Animals↗
PubMed1999

Coil embolization of coronary supply to a cardiac metastasis.

Coil embolization of tumor-related coronary arteries was successful in interrupting coronary supply to a cardiac metastasis from uterine leiomyosarcoma. In patients with cardiac metastases of highly malignant tumors this may be a palliative therapeutic approach.

Aged↗
PubMed1999

Isolated left ventricular abnormal trabeculation in adults is associated with neuromuscular disorders.

BACKGROUND: Isolated left ventricular abnormal trabeculation (ILVAT) is defined as > 3 coarse trabeculations of the left ventricular wall, apically to the papillary muscles, in hearts without congenital malformations. HYPOTHESIS: The aims of the study were to assess by echocardiography the prevalence of ILVAT, to confirm the diagnosis by cardiac magnetic resonance imaging (CMRI), to look for cardiac findings in ILVAT, and to determine whether ILVAT is familial and associated with neurological disorders. METHODS: During a 1-year period (July 1995 to July 1996) all patients in whom transthoracic echocardiography visualized ILVAT, were included in the study. The examination and measurements were performed according to established guidelines. RESULTS: During 1 year, ILVAT was found in 6 of 3,397 patients (0.2%). When applied, CMRI confirmed ILVAT. Four patients had heart failure, all had electrocardiographic (ECG) abnormalities. None of the investigated relatives showed ILVAT. One patient had Becker's muscular dystrophy, three had mitochondrial myopathy, one had polyneuropathy, and one had muscle wasting of unknown origin. CONCLUSIONS: Isolated left ventricular abnormal trabeculation is rare, visible on echocardiography and CMRI, associated with ECG abnormalities, sometimes with heart failure, and always with neuromuscular disorders. Thus, when ILVAT is found, the cardiologist should consider a neurology referral.

Adult↗
PubMed1999

Line Positions and Absolute Intensities in the Laser Bands of Carbon-12 Oxygen-17 Isotopic Species of Carbon Dioxide.

Infrared spectra of a carbon dioxide sample enriched with oxygen-17 have been recorded with a resolution of about 0.0025 cm-1 in the region of the laser bands near 10 and 9 µm, using the long path difference Fourier Transform Spectrometer of the LPMA in Paris. The two laser bands of the 16O12C17O and 17O12C18O species have been analyzed for the first time. Line intensities for several isotopic species have been measured in this region and the rotationless transition dipole moments and Herman-Wallis coefficients of the corresponding bands have been reported. In particular intensities, alternation in the spectra of 17O12C17O has been analyzed. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Analysis of the Infrared Fourier Transform Spectrum of the Spectra of Silane in the Range 2930-3300 cm(-1).

The infrared spectrum of (28)SiH(4) between 2930 and 3300 cm(-1) was recorded using the Laboratoire de Physique Moléculaire et Applications (LPMA.) Fourier transform spectrometer. The instrumental response function width chosen makes it possible to obtain a Doppler-limited spectrum. The observed spectrum belongs to the tetrad built with one quantum of stretching mode (nu(1) or nu(3)) and one quantum of bending mode (nu(2) or nu(4)). The excited states are formed from eight vibrational sublevels: nu(1) + nu(2)(E), nu(1) + nu(4)(F(2)), nu(2) + nu(3)(F(1) + F(2)), and nu(3) + nu(4)(A(1) + E + F(1) + F(2)). The intricacy of the upper states was resolved using the variations of the line strength between the 297 K and 209 K spectra and the precise knowledge of the ground state. For analysis with the vibrational extrapolation method, we used the previous results for the fundamental bending dyad (nu(2)/nu(4)) and the stretching dyad (nu(1)/nu(3)). The Hamiltonian is expanded through the sixth order of approximation for the ground and the bending states, the fifth order for the stretching states, and the fourth order for the tetrad states in the Amat-Nielsen classification. About 1033 pieces of data are used in the analysis and the weighted standard deviation obtained is 4.6 x 10(-3) cm(-1). Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

The Water-Vapor nu(2) Band Lineshift Coefficients Induced by Nitrogen Pressure.

The water-vapor lineshift coefficients in the nu(2) band induced by nitrogen pressure were measured with a FT spectrometer of Paris University at the spectral resolution of 0.005 cm(-1) for the line with angular moment of upper states up to 16. Calculations were made using Anderson formulation of semiclassical impact theory. The calculated lineshifts agree satisfactorily with measured values, but for some lines, deviations were found. The analysis revealed the systematic J trend in subbranches, which consists of transitions with the same values of quantum number K(a) and equally changing K(a) and K(c). Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Prognostic performance and customization of the SAPS II: results of a multicenter Austrian study. Simplified Acute Physiology Score.

OBJECTIVES: To evaluate the prognostic performance of the original Simplified Acute Physiology Score (SAPS) II in Austrian intensive care patients and to evaluate the impact of customization. DESIGN: Analysis of the database of a multicenter study. SETTING: Nine adult medical, surgical, and mixed intensive care units (ICUs) in Austria. PATIENTS: A total of 1733 patients consecutively admitted to the ICUs. MEASUREMENTS AND RESULTS: The database included admission data, SAPS II, length of stay, and hospital mortality. The Hosmer-Lemeshow goodness-of-fit test for the SAPS II showed a lack of uniformity of fit (H = 89.1, 10 df, p < 0.0001; C = 91.8, 10 df, p < 0.0001). Subgroup analysis showed good performance in patients with cardiovascular (medical and surgical) diseases as the primary reasons for admission. A new predictive equation was derived by means of the logistic regression. Goodness-of-fit was excellent for the customized model (SAPS IIAM) (H = 11.2, 9 df, p = 0.33, C = 11.6, 9 df, p = 0.24). The mean standardized mortality ratio (SMR) changed from 0.81 +/- 0.26 to 0.93 +/- 0.29 with customization. CONCLUSIONS: SAPS II was not well calibrated when applied to all patients. However, it performed well for patients with cardiovascular diseases as the primary reason for admission and may thus be applied to these patients. Standardized mortality ratios that are calculated from scoring systems without known calibration must be viewed with skepticism.

Austria↗
PubMed1999

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Journal Article↗
PubMed1999

A comparison of 50, 100 and 200 mg of intra-articular pethidine during knee joint surgery, a controlled study with evidence for local demethylation to norpethidine.

Pethidine (meperidine) is a compound with both local anaesthetic and opioid agonist properties. We have in a recent study demonstrated that pethidine could be an interesting alternative to prilocaine in arthroscopy with local anaesthetic technique. Therefore, we investigated, in a controlled randomized double-blind study, the effect of three doses of pethidine compared with a standard local anaesthetic, in patients subjected to arthroscopic knee joint surgery. Ten patients in each group received 50 mg (P50), 100 mg (P100), 200 mg (P200) of pethidine or prilocaine (5 mg/ml) + adrenaline (4 mg/ml) (PC), injected intra-articularly (i.a.) before surgery. We measured pain intensity and discomfort during arthroscopy and pain intensity at rest and at movement, nausea and tiredness for 3 days post-operatively at regular intervals using the VAS-technique. We also measured the concentration of pethidine and its demethylated metabolite, norpethidine, in plasma by collecting blood samples at 20, 40, 60, 80, 140 and 200 min following injection, and in synovial fluid which was collected through the arthroscope at the start and the end of the surgery. It was found that significantly more patients in the P50 group (n = 6) needed general anaesthesia due to intense pain than those in the P100 group (n = 1), P200 group (n = 0) or the PC group (n = 1). The PC group required significantly more analgesics and had a significantly higher calculated total sum of pain scores at movement post-operatively, than the other three groups. The P200 group more often reported tiredness post-operatively than the other three groups. We conclude that 100 or 200 mg pethidine i.a. produces satisfactory anaesthesia for surgery. There was a rapid transfer of pethidine from synovial fluid to plasma, resulting in plasma levels earlier reported to produce centrally mediated effects, such as analgesia and tiredness. We found much higher concentrations of norpethidine in the synovial fluid than in plasma, suggesting a local demethylation in the knee joint tissues. This site of drug oxidation has not earlier been demonstrated neither in vitro nor in vivo. The results suggest that pethidine given i.a. in the dose range of 50 to 200 mg results in analgesia due to both peripheral and central mechanisms. The significant systemic uptake of pethidine can cause unwanted side-effects.

Adult↗
PubMed1999

In vitro antimalarial activity and cytotoxicity of cochlospermum tinctorium and C. planchonii leaf extracts and essential oils.

The antimalarial and toxicological properties of Cochlospermum tinctorium and C. planchonii extracts and essential oils prepared from their leaves were studied. The oil components were extracted by hydrodistillation of the plant leaves and characterized by gas chromatography and mass spectrometry. Crude extracts and oils were tested for in vitro antimalarial activity on Plasmodium falciparum. The IC50 were evaluated after 24 and 72 h contact between the oils and the parasite culture, and ranged from 22 to 500 micrograms/ml. C. planchonii leaf oil yielded the best antimalarial effect (IC50: 22-35 micrograms/ml), while the most potent effect from crude leaf extracts was induced by C. tinctorium. The cytotoxicity of the leaf crude extracts and oils was assessed on the K562 cell line and showed IC50 values ranging between 33 and 2000 micrograms/ml.

Antimalarials↗
PubMed1999

Evaluation of an interdisciplinary data set for national intensive care unit assessment.

OBJECTIVES: To evaluate the ability of an interdisciplinary data set (recently defined by the Austrian Working Group for the Standardization of a Documentation System for Intensive Care [ASDI]) to assess intensive care units (ICUs) by means of the Simplified Acute Physiology Score II (SAPS II) for the severity of illness and the simplified Therapeutic Intervention Scoring System (TISS-28) for the level of provided care. DESIGN: A prospective, multicentric study. SETTING: Nine adult medical, surgical, and mixed ICUs in Austria. PATIENTS: A total of 1234 patients consecutively admitted to the ICUs. INTERVENTIONS: Collection of data for the ASDI data set. MEASUREMENTS AND MAIN RESULTS: The overall mean SAPS II score was 33.1+/-2.1 points. SAPS II overestimated hospital mortality by predicting mortality of 22.2%+/-2.9%, whereas observed mortality was only 16.8%+/-2.2%. The Hosmer-Lemeshow goodness-of-fit test for SAPS II scores showed lacking uniformity of fit (H = 53.78, 8 degrees of freedom; p < .0001). TISS-28 scores were recorded on 8616 days (30.6+/-1.5 points). TISS-28 scores were higher in nonsurvivors than in survivors (30.4+/-0.9 vs. 25.7+/-0.4, respectively; p < .05). No significant correlation between mean TISS-28 per patient per unit on the day of admission and mean predicted hospital mortality (r2 = .23; p < .54) or standardized mortality ratio per unit (r2 = -.22; p < .56) was found. CONCLUSIONS: Implementation of an interdisciplinary data set for ICUs provided data with which to evaluate performance in terms of severity of illness and provided care. The SAPS II did not accurately predict outcomes in Austrian ICUs and must, therefore, be customized for this population. A combination of indicators for both severity of illness and amount of provided care is necessary to evaluate ICU performance. Further data acquisition is needed to customize the SAPS II and to validate the TISS-28.

APACHE↗
PubMed1998

Dual effect of interleukin 4 on HIV-1 expression: implications for viral phenotypic switch and disease progression.

We report that interleukin 4 (IL-4) inhibits the propagation of non-syncytia-inducing and increases the propagation of syncytia-inducing HIV-1 isolates by two mechanisms. It differentially regulates the two major HIV-1 coreceptors, CCR5 and CXCR4, in human peripheral blood mononuclear cells, increasing CXCR4 and decreasing CCR5 expression in primary CD4(+) T-lymphocytes. In addition, IL-4 stimulates the expression of all HIV-1 isolates via a transcriptional activation mechanism. The combination of these effects results in increased propagation of CXCR4-using and inhibition of CCR5-using HIV-1 strains. IL-4 also activates HIV-1 expression in primary monocytes/macrophages but does not affect CCR5 expression. These results identify IL-4 as an important regulator of HIV-1 and suggest a critical role for this cytokine in the control of viral evolution and in the phenotypic switch from non-syncytia-inducing to syncytia-inducing, which leads to accelerated disease progression.

CD4-Positive T-Lymphocytes↗
PubMed1998

Infrared Fundamental and First Hot Bands of O12C17O Isotopic Variants of Carbon Dioxide.

Infrared spectra of 16O12C17O, 17O12C17O, and 17O12C18O in a carbon dioxide sample enriched with oxygen-17 have been recorded with a resolution of about 0.0025 cm-1 in the regions of the fundamental bands, nu2 (600-800 cm-1) and nu3 (2200-2400 cm-1), and in the region of the "forbidden" band, nu1 (1200-1400 cm-1), using the long path difference Fourier transform spectrometer of the LPMA in Paris. For each species, the first hot band in the 4.5-µm region and two hot bands at least in the 15-µm region have been studied for the first time, and a simultaneous reduction of wavenumbers measured in different spectral regions has been carried out yielding new or improved spectroscopic constants. Line intensities have been measured in the region of the nu2 and nu3 bands of 16O12C17O, and the corresponding rotationless transition dipole moments and Herman-Wallis coefficients have been reported. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

In vitro antiplasmodial activity of stem and root extracts of Nauclea latifolia S.M. (Rubiaceae).

Aqueous extracts from Nauclea latifolia S.M. (Rubiaceae), a plant commonly used in Ivory Coast by traditional healers for the treatment of malaria, were tested on two strains of Plasmodium faliparum: FcB1-Colombia (chloroquine-resistant) and a Nigerian strain (chloroquine-sensitive). The extracts were obtained from stems and roots of the plant in two forms, infusion and decoction, both methods used by most traditional healers. The in vitro activity of N. latifolia extracts on P. falciparum was assessed both visually and by a radioactive method. The visual analysis allowed determination of the time of extract action on the erythrocytic cycle, as well as the parasitic stage of most inhibitory effect. Similar results were obtained applying fresh, frozen or lyophilized extracts. The IC50 values determined were within the range already reported for other antimalarial plants such as Azadirachta indica A. Juss (Meliaceae) or Artemisia annua L. (Asteraceae). Aqueous extracts of N. latifolia inhibited P. falciparum (FcB1 strain) mainly at the end of the erythrocytic cycle (32nd to 48th hour).

Animals↗
PubMed1998

Intrathecal administration of sameridine to patients subjected to arthroscopic knee joint surgery.

BACKGROUND: Sameridine, a new substance with both local anesthetic and opioid effects, was administered intrathecally for the first time to humans, i.e. in patients subjected to arthroscopic knee joint surgery. METHOD: A dose-escalating (10, 15, 20 and 25 mg), open study was performed in 33 patients. Only two patients were included in the 25 mg group. RESULTS: Sameridine provided good quality of surgical anesthesia in all patients except those receiving 10 mg. The maximum level of sensory block, Th5-Th7, was reached within 30 min with a median duration of 3.6-3.9 h. The motor block was more profound with increasing dose, but never lasted longer than the sensory block. The influence on heart rate and blood pressure was minor and atropine and ephedrine were needed in four patients. No clinically significant ECG-changes were detected and no arrhythmias were recorded. Oxygen saturation and respiratory rate did not decrease in a clinically significant way and were not affected by concomitant morphine given i.v. postoperatively. There were few side-effects, the most frequent being mild pruritus (10/33). CONCLUSION: Sameridine provided clinically adequate anesthesia for the patients receiving the doses of 15, 20 and 25 mg. Further studies are needed to evaluate the substance and it is of great interest to clinically investigate the opioid component with respect to postoperative analgesia.

Adolescent↗
PubMed1998

Early arthroscopic treatment of primary traumatic anterior shoulder dislocation. A follow-up study.

This study evaluates the results of early arthroscopic Bankart repair in patients with primary traumatic anterior dislocation of the shoulder. The patients' age range was 17-34 years. Arthroscopic Bankart repair was performed within 12 days after the dislocation. First follow-up was at 18 months. According to Rowe's score, 11 patients (73%) were excellent, 3 (20%) were good and 1 (7%) was poor. The median external rotation deficit was 4 degrees in the adducted position. At a second follow-up at 34 months, two patients had redislocated. Both of these patients had severe generalized joint laxity. Another patient reported frequent subluxations. We conclude that in young patients with primary anterior traumatic shoulder dislocation, early arthroscopic Bankart repair implies a low recurrence rate and restores shoulder function to normal. Generalized joint laxity could indicate an increased risk for recurrent dislocation.

Adolescent↗