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Biomedical subjects

A Pau

Publications and source records attributed to A Pau.

At least 19 recordsLinked to original sources

Thienocinnolinone alkanoic acid derivatives as aldose reductase inhibitors.

A new series of 8-halogen-4,4a,5,6-tetrahydrothieno[2,3-h]cinnolinone-N2-alkanoic acids was prepared and tested for aldose reductase (ALR2) inhibitory activities. These compounds showed significant inhibitory activity against bovine lens ALR2, with the best compound 2e showing an IC(50) value of 31.4 microM. The presence of the C8-substituents here studied (Cl, Br) on the thienocinnolinone scaffold caused a decrease of the inhibitory potency by a factor of about 4 with respect to the unsubstituted parent compound, while the presence of a C8-methyl group, considered in a previous paper decreased the activity by a factor of about 2. Moreover, the length of the N2 alkanoic chain influences strongly the enzyme inhibitory activity. While most of the carboxylic acids ALR2 inhibitors are acetic acid derivatives, in the case of thienocinnolinone compounds, homologues higher than acetic acids showed to be more active.

Aldehyde Reductase↗

Determination of phenol and o-cresol by GC/MS in a fatal poisoning case.

A fatality due to the ingestion of solution containing phenol and o-cresol is described. The pathological findings were typical of acute substantial poisoning. Blood, urine and stomach content were obtained during post mortem examinations. Phenol and o-cresol were identified using GC/MS. The extractions from autopsy materials were obtained as follows: by gel permeation with cyclohexane/dichloromethane from stomach content, by solid phase extraction (SPE) from urine and by deproteinization with acetonitrile from blood. The phenol and o-cresol concentrations in the samples were found, respectively, as follows: 115.0 and 5.0 microg/g in the stomach contents, 58.3 and 1.9 microg/ml in the blood, 3.3 and 20.5 microg/ml in the urine. Distributions of phenol in fatal poisonings have been reported, but, usually, colorimetry was used as the analytical method and it cannot exclude the interference of other phenolic compounds.

Adult↗

Synthesis and aldose reductase inhibitory activities of novel thienocinnolinone derivatives.

A novel series of tetrahydrothieno[2,3-h]cinnolinone derivatives were synthesized and evaluated in vitro for their ability to inhibit aldose reductase (ALR2), an enzyme involved in the appearance of diabetic complications. Compounds 2e and 2j exert a remarkable inhibitory effect, with IC(50) of 7.6 and 18 microM, respectively. These compounds incorporate a valid pharmacophore for aldose reductase inhibitory activity represented by a thienocinnolinone template linked through a pentamethylene spacer to a carboxylic function.

Aldehyde Reductase↗

Synthesis and cytotoxicity of substituted 2-benzylnaphth[2,3-d]imidazoles.

Designed as a new series of so called "bivalent ligand" containing the proposed 2-benzylnaphthimidazole-type structure, a number of 2-benzylnaphth[2,3-d]imidazoles, bearing various substituents, have been prepared by a synthetic approach involving an heterocyclization of 2,3-diaminonaphthalene 4 with appropriate imidates 3 (for 1b-i) followed by alkylation (for 1j-l) with the desired alkylating agent. Compounds 1b-f, h-l were subjected to primary biological evaluation for cancer cell growth inhibition (one-dose, three-cell assay), and the four most active terms, 1c, h, i and j, were then evaluated for their cytotoxic profiles in the National Cancer Institute's (NCI) human disease-oriented, 60 cell line, in vitro antitumor screening protocol. Among them, two compounds (1h and 1i) are the most representatives demonstrating not only high growth-inhibitory activities against some leukemia cancer cells, but also fairly good activities against the growth of certain cell lines of some solid tumors.

Antineoplastic Agents↗

HIV-associated non-Hodgkin lymphoma: incidence, presentation, and prognosis.

Patients with acquired immunodeficiency syndrome (AIDS)-associated non-Hodgkin lymphoma often present with multiple poor prognostic features, including significant tumor burden, advanced immunosuppression, and other concurrent morbidities. Strategies to manage such complex multiple-disease cases have often incorporated the assumption that prospects for long-term survival are poor and that intensive therapy cannot be tolerated and so is not justified. Since the advent of highly active antiretroviral therapy for human immunodeficiency virus infection, life expectancy has improved substantially for patients in whom the virus can be successfully suppressed. Thus, for complicated cases involving AIDS-associated malignancy, a reassessment of treatment strategies and the potential for long-term survival is warranted. Here, we present the case of a patient with poor prognosis due to AIDS-associated lymphoma with leptomeningeal involvement, advanced immunosuppression, and deep venous thrombosis. The management of this case illustrates that a multidisciplinary approach to complex AIDS cases involving malignancy and concurrent morbidity can result in a return to functional health in affected patients. Successful strategies for achieving favorable outcomes currently exist with available therapies.

Antineoplastic Combined Chemotherapy Protocols↗

Increased cell proliferation and associated expression of PDGFRbeta causing hypercellularity in patellar tendinosis.

OBJECTIVE: This study assessed cellularity in patellar tendinosis with respect to cell proliferation and the expression of platelet-derived growth factor receptor beta (PDGFRbeta). METHODS: Surgical samples were taken from 11 patients fulfilling criteria of patellar tendinosis and from 12 matched controls. Standard immunohistochemistry methods were used to detect expression of PDGFRbeta and proliferation cell nuclear antigen (PCNA). Results were analysed by computer-assisted microscopy. Tendon cells were isolated from nine tendinosis and eight control tissues for cell culture. RESULTS: Increased cellularity (P<0.001) was observed in tendinosis tissues compared with controls, and also a higher proliferative index (P:<0.001). Increased expression of PDGFRbeta was demonstrated (P<0.001). Cultured tendinosis cells showed a higher proliferation rate than controls (P<0.001). This was maintained when the cells were cultured under various conditions of serum supplementation (P<0.01). Tendinosis cells also showed a higher proliferation rate (P<0.01) in medium containing 10 ng/ml PDGF. CONCLUSION: Hypercellularity in patellar tendinosis is caused by increased cell proliferation and is associated with increased expression of PDGFRbeta.

Adolescent↗

The subchoroidal approach to the third ventricle: surgical anatomy according to Galen.

THE SUBCHOROIDAL APPROACH has taken its place among the surgical access routes to the third ventricle. Eighteen centuries ago, in his major anatomic work, Galen detailed with astonishing accuracy the anatomy of the structures around the third ventricle and the procedure for exposing this cavity by entering the lateral ventricles and elevating its roof. Even more surprising is Galen's pioneering description of surgical maneuvers of the third ventricle in living animals in a way that anticipated the modern subchoroidal approach.

Anatomy↗

Anti-inflammatory and analgesic amides: new developments.

A series of substituted N-cycloalkyl benzamides, cinnamamides, and indole-3-carboxamides were synthesized and evaluated for their analgesic, antiinflammatory activities as well as for their gastrointestinal irritation liability. Indomethacin was used as reference drug in both tests. Compounds 1k, 1b, 1h, 1j, and 1g were the most active in the antiinflammatory paw edema inhibition test, with a sharply dose-dependent effect. In terms of the analgesic activity (acetic acid writhing test), the most active compound was 5a followed by 3a, but many other compounds were found to have a non-negligible potency. Even in this case, the effect was dose dependent.

Amides↗

The angiogenesis marker ED-B+ fibronectin isoform in intracranial meningiomas.

Fibronectins (FNs), adhesive glycoproteins mainly expressed in the extracellular matrix, are polymorphic molecules whose various isoforms are dependent on alternative splicing patterns. The isoform containing the ED-B sequence and occurring in foetal and neoplastic tissues (oncofoetal or B+FN) has been previously recognized as a marker for angiogenesis. The distribution of this isoform was analyzed in a consecutive series of 134 surgically obtained intracranial meningiomas, using specific monoclonal antibodies. Oncofoetal FN was found to be widely distributed in the vessels of anaplastic meningiomas, with its expression being restricted in the vasculature of the typical subtypes. and absent in the neighbouring cerebral tissue. The ubiquitous vascular expression of B+FN in meningiomatous malignancies might provide a potential target for the in vivo delivery of angiosuppressive agents.

Biomarkers, Tumor↗

The effect of ritonavir on the pharmacokinetics of meperidine and normeperidine.

STUDY OBJECTIVE: To determine the effects of ritonavir on the pharmacokinetics of meperidine and normeperidine. DESIGN: Open-label, crossover, pharmacokinetic study. SETTING: United States government research hospital. SUBJECTS: Eight healthy volunteers who tested negative for the human immunodeficiency virus. INTERVENTION: Subjects received oral meperidine 50 mg and had serial blood samples collected for 48 hours. They then received ritonavir 500 mg twice/day for 10 days, followed by administration of a second 50-mg meperidine dose and collection of serial samples. MEASUREMENTS AND MAIN RESULTS: Plasma samples were assayed for meperidine, normeperidine, and ritonavir. Meperidine's area under the curve (AUC) decreased in all subjects by a mean of 67+/-4% in the presence of ritonavir (p<0.005). Mean +/- SD maximum concentration was decreased from 126+/-47 to 51+/-21 ng/ml. Normeperidine's mean AUC was increased 47%, suggesting induction of hepatic metabolism. CONCLUSION: Meperidine's AUC is significantly reduced, not increased, by concomitant ritonavir. Based on these findings, the risk of narcotic-related adverse effects from this combination appears to be minimal. However, increased concentrations of normeperidine suggest a potential for toxicity with increased dosages or long-term therapy.

Adult↗

A risk-benefit assessment of interleukin-2 as an adjunct to antiviral therapy in HIV infection.

Immunomodulation has become a major focus of HIV research in an effort to augment, boost or restore the patient's damaged immune system. Recombinant interleukin-2 is currently being studied in phase II/III trials in HIV-infected patients. Several clinical studies have demonstrated that intermittent regimens are associated with marked rises in CD4+ cell counts without an increase in viral load. Most of these studies employ 5 consecutive days of interleukin-2 therapy by continuous intravenous infusion or subcutaneous injection, repeated every 8 weeks. An alternative strategy is the daily administration of low doses of interleukin-2, but clinical experience with this regimen is limited. Interleukin-2 administration can adversely affect virtually every organ system, requiring aggressive supportive care. A variety of administration strategies and interventions are being evaluated to minimise toxicity. Currently, no clinical end-point data are available for interleukin-2 in HIV-infected patients. Until phase III studies are completed, interleukin-2 can be used in the research setting as an immunomodulator and adjunct to antiretroviral therapy. Its potential to activate latently infected cells and promote HIV eradication from reservoir sites is also an important area for further study. If clinical benefit can be demonstrated, interleukin-2 could be useful as an adjunct to antiretroviral therapy if adverse effects can be minimised and therapy can be given infrequently on an outpatient basis.

Anti-HIV Agents↗

Antidermatophytic action of new 1-naphthylmethyl and benzo[b]thiophen-7-ylmethyl hydrazones related to inhibitors of squalene epoxidase.

Two series of hydrazonic compounds related to main classes of inhibitors of fungal squalene epoxidase (SE) were designed and prepared on the hypothesis of a pharmacophoric model. The antifungal activity of the new compounds was evaluated in vitro against dermatophytes, moulds and yeasts. Antidermatophytic activity resulted for several hydrazones, particularly for those containing a tett-butylacetylenic group, supporting the hypothesis that the introduction of a hydrazonic function in the model could retain the antimycotic activity.

Arthrodermataceae↗

Synthesis of substituted N-(4-piperidyl)-N-(3-pyridyl)amides with antiarrhythmic activity. Note 1.

The synthesis of analogues of N,2-diphenyl-N-(4-piperidyl)acetamide endowed with antiarrhythmic activity is reported. Benzoyl, cinnamoyl, acetyl and propionyl groups replace the phenacyl group as N-acyl substituent, while pyridine replaces benzene as aromatic ring bound to the amide nitrogen. The title compounds were evaluated for antiarrhythmic activity on experimental arrhythmias induced by aconitine in rats. The presence of a n-propyl chain and an unsubstituted cinnamoyl moiety (1j) gives the highest protection against aconitine induced extrasystoles while the best efficacy against lethal effects is due to the presence of a n-propyl chain and an acetyl moiety (1m).

Aconitine↗

Monitoring of oxytetracycline in ovine milk by high-performance liquid chromatography.

A method for 'in vivo' determination of the oxytetracyclin residues in ovine milk at low levels is described. Two groups of Sardinian breed sheep were treated with a dose of oxytetracycline by intramammary infusion and intramuscular administration, respectively. Oxytetracycline residues in extracts obtained from a preliminary cleanup procedure, were detected by an isocratic high-performance liquid chromatography (HPLC) method. Linear calibration plots were obtained over a large concentration range of 1 mg ml(-1)-10 ng ml(-1), with correlation coefficients higher than 0.996. Recoveries between 85.8 and 98.9% were obtained. Limit of detection (LOD) and limit of determination (LOQ) were 5.2 and 17.5 ng ml(-1), respectively. This method would be useful for routine monitoring of oxytetracycline residues in ovine dairy milk.

Animals↗

Synthesis of 1-methyl-4-(N-aroyl)-piperidinamides with anti-inflammatory and analgesic activities.

Two series of 1-methyl-4-(N-aroyl)-piperidinamides were synthesized and evaluated for their anti-inflammatory and analgesic properties, as well as for their gastrointestinal irritation liability. A non-aromatic derivative, 1-methyl-4-(N-cyclohexanoyl)-piperidinamide, was synthesized and evaluated in order to obtain a more exhaustive knowledge of the structure-activity relationship.

Amides↗