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R Colle

Publications and source records attributed to R Colle.

At least 19 recordsLinked to original sources
PubMed2002

Soil CO2 fluxes in cereal land use of the Spanish plateau: influence of conventional and reduced tillage practices.

From November 1998 to October 2000, measurements of soil respiration were performed on the Spanish plateau for two patches of non-irrigated barley, one managed with conventional tillage (CT) and the other with reduced tillage (RT). Soil CO2 flux showed seasonal variation on both patches, with an increase from March to October, peaking in May, and a decrease during the winter period by a factor of around 2. The mean value for both combined years was 2.03 and 1.70 micromol m(-2) S(-1), in the CT and RT patches, respectively. In order to analyse the influence of RT on soil CO2 flux, two tests were performed. The first one was the Kruskal-Wallis test to compare whether the differences between the medians in both patches were statistically significant. The results obtained revealed statistically significant differences during the second year, at a 85% and 95% significance level, use being made of annual data and that recorded during the period of maximum interest, March-October, respectively. The decrease in soil respiration in the RT patch was around 24%. The second test was aimed at describing and comparing the influence of soil temperature on soil CO2 flux. By using the data of both patches recorded during the first year, an empirical equation on 10-cm soil temperature was fitted and tested on the data corresponding to the second year in each of the patches. Then, a comparison between the medians of the differences between the estimated and observed values was again performed by means of the Kruskal-Wallis test. The over-prediction of the model in the RT patch, statistically significant at a 90% significance level, was roughly 23%, confirming again the decrease in soil respiration one year after this agricultural management practice had been implemented.

Agriculture↗
PubMed1999

Use of medical resources and quality of life of patients with chronic heart failure: a prospective survey in a large Italian community hospital.

AIMS: To assess the prevalence, clinical characteristics, use of medical resources and quality of life in consecutive patients with chronic heart failure (CHF) hospitalized in a large community hospital during 3 months. METHODS AND RESULTS: The study group included 354 patients with CHF, admitted in the Departments of Internal Medicine (97%) and Cardiology. Median age was 78 years [72;85], 45% were males. CHF was the main diagnosis in 72%; 28% were in NYHA class III and 49% in class IV; 42% had atrial fibrillation. The median hospital stay was 8 days [5;14], in-hospital mortality 9% in those admitted for CHF and 19% in those admitted primarily for other diseases. Patients with CHF occupied 15% of the beds; 1330 ECGs, 389 chest X-rays, 112 echocardiograms and 10 coronary angiograms were performed. A quality of life questionnaire revealed that 82% had problems with mobility, 54% with self-care and 88% with everyday activity. Thirty-nine percent of patients had at least one hospitalization during the previous year. CONCLUSIONS: Ninety-seven percent of hospitalized patients with CHF are admitted in the Internal Medicine wards and occupy 15% of beds. The majority of the patients are 72 years or older, with severe heart failure. The frequency of rehospitalization(s) and mortality rate in this population remains high. Echocardiography is performed only in 27% of patients.

Aged↗
PubMed1997

Interferon therapy in HCV-positive mixed cryoglobulinaemia: viral and host factors contributing to efficacy of the therapy.

BACKGROUND: In a previous paper, we reported on the short-term efficacy of alpha-interferon in the treatment of hepatitis C virus positive mixed cryoglobulinaemia. AIMS: We investigated the long-term effects of therapy in a larger group of patients, and the viral and host factors able to influence the response to treatment. METHODS: In 27 females and 15 males (mean age 54.8 +/- 9.1 years) affected by mixed cryoglobulinaemia, bone marrow biopsy and phenotyping of marrow cells were performed before treatment and at the end of follow-up. A liver biopsy was obtained from patients showing biochemical signs of chronic liver disease. The presence of hepatitis C virus was assessed by detection of serum anti-hepatitis C virus antibodies, and hepatitis C virus-RNA. The treatment schedule was 3 million units of recombinant interferon alpha-2b three times a week for one year. Follow-up lasted for 1 year after the end of treatment. The response was classified as follows: 1) Complete response: Disappearance of the cryocrit (or reduction of more than 50%) and of all clinical manifestations of the disease. 2) Partial response: Disappearance of all clinical signs of the disease, but reduction of cryocrit of less than 50%. 3) Minor response: Reduction of cryocrit of less than 20% associated with the disappearance of one or more (but not all) signs of vasculitis. RESULTS: Anti-hepatitis C virus antibodies were present in 41 (95%) patients, and hepatitis C virus-RNA was detectable in all cases. Before therapy, marrow histology showed a massive monomorphous infiltration by plasmacytoid lymphocytes indicating the presence of low-grade non-Hodgkin lymphoma in 7 cases (16.6%). After therapy, 13 (31%) patients achieved a complete response, 23 patients (55%) a partial response, and 6 patients (14%) a minor response. Seven of the responders and all patients showing partial or minor responses relapsed a few months after withdrawal of therapy. At the end of the follow-up, only 6 patients had obtained complete remission. Bone marrow examination showed that B-lymphocytic monoclonal infiltrate had disappeared in 3 long-term responders. No difference was found between responders and non-responders/relapsers in terms of age, sex, duration of the disease, severity of symptoms, liver function tests, rheumatoid factor or complement levels, while the lack of response was associated with the presence of genotype 1b, liver cirrhosis, and high cryoglobulin level. CONCLUSIONS: Mixed cryoglobulinaemia is associated with a high prevalence of B-cell lymphomas. Alpha-Interferon is an effective agent for the treatment of this disease and seems able to determine regression of the lymphoproliferative disorder. The hepatitis C virus genotype and cryoglobulin level are the most important predictive factors of response to therapy.

Antiviral Agents↗
PubMed1995

Human herpesvirus 6 and human herpesvirus 7 in chronic fatigue syndrome.

We analyzed lymphocytes of patients with chronic fatigue syndrome (CFS) for the presence of human herpesvirus 6 (HHV-6) and HHV-7 DNA. HHV-7 was present in over 80% of CFS patients and healthy controls, while the prevalence of HHV-6 variant A increased significantly in CFS cases (22 versus 4%; P = 0.05).

Adult↗
PubMed1992

Substituted 1-(aminomethyl)-2-(arylacetyl)-1,2,3,4-tetrahydroisoquinolines: a novel class of very potent antinociceptive agents with varying degrees of selectivity for kappa and mu opioid receptors.

This study describes the synthesis of a series of novel substituted 1-(aminomethyl)-2-(arylacetyl)-1,2,3,4-tetrahydroisoquinolines, and discusses their structure-activity relationships (SARs) using binding affinity for opioid receptors and antinociceptive potency as the indices of biological activity. The introduction of a hydroxy substituent in position 5 of the isoquinoline nucleus generated a compound, 40, which is 2 times more potent than the previously disclosed unsubstituted analogue 39 in mouse models of antinociception. A QSAR analysis of the 5-substitution clearly demonstrates that antinociceptive activity is inversely associated with the lipophilicity of the substituents. The substituted compounds described herein are less selective for the kappa opioid receptors than the unsubstituted isoquinoline 39. For example, the 5-hydroxy-substituted compound 59 shows high affinity for kappa opioid receptors (Ki kappa = 0.09 nM) and a Ki mu/Ki kappa ratio of only 5. However, a multiple linear regression analysis demonstrates a lack of correlation between antinociceptive activity and affinity for the mu opioid receptor. On the other hand, the correlation between binding affinity to kappa opioid receptor and antinociceptive activity was statistically significant.

Analgesics↗
PubMed1992

Enantiospecificity of kappa receptors: comparison of racemic compounds and active enantiomers in two novel series of kappa agonist analgesics.

Two novel series, Ia,b and IIa,b, of kappa opioid antinociceptive agents have recently been described. 2a,b,3a,b,c The biological activities of 16 racemic compounds and their corresponding (-) enantiomers are now compared in a battery of tests. Enantiomers of unsubstituted piperidines Ia were synthesized starting from S(-) pipecolic acid, whereas the enantiomerically pure substituted piperidines (Ib), tetrahydroisoquinolines (IIa), and thienopiperidines (IIb) were, in general, obtained after diastereomeric crystallization of the corresponding tartrate salts. The absolute stereochemistry of one representative enantiomer from series IIa was determined to be (1S) by X-ray crystallographic analysis. Antinociceptive activity in the mouse abdominal constriction and tail-flick tests following subcutaneous administration, and binding affinity for kappa and mu receptors, were found to reside predominantly in the (-) enantiomers. Consequently, racemic compounds showed approximately half potency of the corresponding enantiomers. This potency difference was less clear after oral administration presumably due to small differences in bioavailability of the two corresponding enantiomers. For compounds with some affinity also for mu receptors (Ki less than 1,000 nM), the kappa/mu selectivity was maintained within each enantiomeric pair, in contrast to results found for other kappa agonists.

Analgesics↗
PubMed1991

(2S)-1-(arylacetyl)-2-(aminomethyl)piperidine derivatives: novel, highly selective kappa opioid analgesics.

This paper describes the synthesis and structure-activity relationships as kappa opioid analgesics of a novel class of 1-(arylacetyl)-2-(aminomethyl)piperidine derivatives. The active conformation of the pharmacophore, with a torsional angle (N1C2C7N8) of 60 degrees, was defined with computational studies and 1H NMR. A quantitative structure-activity relationship study of the arylacetic moiety substitution indicated that the presence of an electron-withdrawing and lipophilic substituent in para and/or meta positions is required for good analgesic activity and kappa affinity. The lead compounds (2S)-1-[(3,4-dichlorophenyl)acetyl]-2-(pyrrolidin-1-ylmethyl )piperidine hydrochloride and (2S)-1-[4-(trifluoromethyl)phenyl]acetyl]-2-(pyrrolidin-1-ylmet hyl) piperidine hydrochloride are the most kappa/mu selective (respectively 6500:1 and 4100:1) and among the most potent (Ki kappa 0.24 and 0.57 nM, respectively) kappa ligands identified so far. In the mouse tail flick model of antinociception, compound 14 (ED50 = 0.05 mg/kg sc) was 25 times more potent than morphine and 16 times more potent than the standard kappa ligand U-50488.

Analgesics↗
PubMed1991

(1S)-1-(aminomethyl)-2-(arylacetyl)-1,2,3,4-tetrahydroisoquinoline and heterocycle-condensed tetrahydropyridine derivatives: members of a novel class of very potent kappa opioid analgesics.

The synthesis and structure-activity relationship (SAR) of a novel class of kappa opioid analgesics, 1-(aminomethyl)-2-(arylacetyl)-1,2,3,4- tetrahydroisoquinolines and (aminomethyl)-N-(arylacetyl)-4,5,6,7-tetrahydrothienopyridines+ ++, are described. These compounds, formally derived by the condensation of a benzene or thiophene ring on the piperidine nucleus of the recently described compounds 1, are from 3 to 7 times more potent as antinociceptive agents and with a longer duration of action than the original lead compounds. A similar N2-C1-C9-N10 pharmacophore torsional angle of approximately 60 degrees was also found for this class of compounds by using X-ray and 1H NMR analyses. The same absolute configuration (S) at the chiral center of the active (-) enantiomers was determined by X-ray crystallographic analysis. A varied degree of kappa receptor selectivity was a feature of this novel class of antinociceptive agents (mu/kappa ratio from 44 to 950 according to the nature of the basic moiety). SAR analysis indicated that the presence of electron-withdrawing and lipophilic substituents in para and/or meta positions in the arylacetic moiety and the pyrrolidino or dimethylamino basic groups are required to optimize biological activity. The lead compounds 28, 30, and 48 are among the most potent antinociceptive agents (ED50 ca. 0.020 microM/kg sc) and kappa ligands (Ki(kappa) ca. 0.20 nM) identified so far.

Analgesia↗
PubMed1989

[Oral bacteriotherapy with Bifidobacterium bifidum and Lactobacillus acidophilus in cirrhotic patients].

Thirty-five patients with alcohol cirrhosis were treated for several months (average 4 months) with Infloran (6 capsules daily). Thirty cirrhotics were treated for the same length of time with lactulose and diuretics. Infloran-treated patients showed reduced ammonium levels, improvement of mental status and psychological performance. In addition, patients who required hospitalization had shorter in-patient periods thanks to a more rapid psychological and physical improvement. Infloran may be considered a valid alternative to conventional therapy for the out-patient management of subjects with alcoholic cirrhosis.

Ammonia↗