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4.
An Sist Sanit Navar ; 44(2): 205-214, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34132247

ABSTRACT

BACKGROUND: The aim of this paper is to analyze the role of the biomarkers Interleukin 6, Tumoral Necrosis Factor a, sCD40L, high sensitive Troponin T, high sensitive C-Reactive Protein and Galectin-3 in predicting super response (SR) to Cardiac Resynchronization Therapy (CRT), as they have not been studied in this field before. METHODS: Clinical, electrocardiographic and echocardiographic data was obtained preimplant and after one year. SR was defined as reduction in LVESV = 30% at one year follow-up. Blood samples were extracted preimplant. Multivariate logistic regression and ROC curves were performed. RESULTS: 50 patients were included, 23 (46%) were SR. Characteristics related to SR were: female (35 vs. 11%, p?=?0.04), suffering from less ischemic cardiomyopathy (13 vs. 63%, p?

Subject(s)
Cardiac Resynchronization Therapy , Heart Failure , Echocardiography , Electrocardiography , Female , Heart Failure/therapy , Humans , Treatment Outcome
5.
J Intern Med ; 289(5): 709-725, 2021 05.
Article in English | MEDLINE | ID: mdl-33107650

ABSTRACT

PURPOSE: Pseudoxanthoma elasticum (PXE) is a recessive disorder involving skin, eyes and arteries, mainly caused by ABCC6 pathogenic variants. However, almost one fifth of patients remain genetically unsolved despite extensive genetic screening of ABCC6, as illustrated in a large French PXE series of 220 cases. We searched for new PXE gene(s) to solve the ABCC6-negative patients. METHODS: First, family-based exome sequencing was performed, in one ABCC6-negative PXE patient with additional neurological features, and her relatives. CYP2U1, involved in hereditary spastic paraplegia type 56 (SPG56), was selected based on this complex phenotype, and the presence of two candidate variants. Second, CYP2U1 sequencing was performed in a retrospective series of 46 additional ABCC6-negative PXE probands. Third, six additional SPG56 patients were evaluated for PXE skin and eye phenotype. Additionally, plasma pyrophosphate dosage and functional analyses were performed in some of these patients. RESULTS: 6.4% of ABCC6-negative PXE patients (n = 3) harboured biallelic pathogenic variants in CYP2U1. PXE skin lesions with histological confirmation, eye lesions including maculopathy or angioid streaks, and various neurological symptoms were present. CYP2U1 missense variants were confirmed to impair protein function. Plasma pyrophosphate levels were normal. Two SPG56 patients (33%) presented some phenotypic overlap with PXE. CONCLUSION: CYP2U1 pathogenic variants are found in unsolved PXE patients with neurological findings, including spastic paraplegia, expanding the SPG56 phenotype and highlighting its overlap with PXE. The pathophysiology of ABCC6 and CYP2U1 should be explored to explain their respective role and potential interaction in ectopic mineralization.


Subject(s)
Cytochrome P450 Family 2/genetics , Multidrug Resistance-Associated Proteins/genetics , Pseudoxanthoma Elasticum/genetics , Spastic Paraplegia, Hereditary/genetics , Calcinosis , Cytochrome P-450 Enzyme System/metabolism , Eye/pathology , HEK293 Cells , Humans , Mutation, Missense , Phenotype , Pseudoxanthoma Elasticum/metabolism , Pseudoxanthoma Elasticum/pathology , Retrospective Studies , Skin/pathology , Spastic Paraplegia, Hereditary/metabolism , Spastic Paraplegia, Hereditary/pathology
6.
Ann Dermatol Venereol ; 147(11): 706-712, 2020 Nov.
Article in French | MEDLINE | ID: mdl-32653218

ABSTRACT

BACKGROUND: Early detection of melanoma constitutes a major challenge and is a common reason for dermatological consultations. There is no recent data on melanomas diagnosed in the private medical sector in France, nor on the circumstances of diagnosis. PATIENTS AND METHODS: This was a retrospective observational study on records collating data on all new consecutive cases of melanoma diagnosed between January 2015 and June 2018, in the private sector only, by volunteer dermatologists belonging to the association for continuing medical education, "Dermatologie Paris XV". A data collection sheet was prepared on which to record information about the dermatologist, the patient, the main complaint, the characteristics of the melanoma, and the initial treatment given, using the computerized list provided by our dermatopathology offices. RESULTS: The study involved 383 cases of melanoma, 37% in situ and 63% invasive, which consisted chiefly of superficial spreading melanoma. The median age of the cohort was 61 years and patients were predominantly female (58%). Follow-up of high-risk patients and complete routine examination (in those consulting for another reason) resulted in direct detection by a dermatologist of 202 of the 383 melanomas (52.7%); these melanomas had a lower median Breslow index than the rest of the cohort and were thin in the main. When patients consulted for a suspect lesion (139 cases), the lesion had been identified mostly by either the patient or by a relative (61% of cases). The decision to consult was made chiefly by the patients themselves, and the Breslow index was thicker. An initial consultation for nevus screening resulted in diagnosis of 42 melanomas, i.e. only 11% of the cohort. Dermoscopy was performed by 92% of the dermatologists participating in the study. Melanoma excision was performed in the office by the practitioner in 75% of cases, and management was validated at multidisciplinary meetings in 65% of cases. CONCLUSION: In terms of French primary care, dermatologists in private practice play a key role in ensuring early detection and initial management of melanoma.


Subject(s)
Melanoma , Nevus, Pigmented , Skin Neoplasms , Dermatologists , Female , Humans , Infant, Newborn , Melanoma/diagnosis , Melanoma/epidemiology , Private Practice , Skin Neoplasms/diagnosis , Skin Neoplasms/epidemiology
7.
Handb Exp Pharmacol ; 247: 227-260, 2018.
Article in English | MEDLINE | ID: mdl-28035528

ABSTRACT

Delta opioid receptor (DOR) displays a unique, highly conserved, structure and an original pattern of distribution in the central nervous system, pointing to a distinct and specific functional role among opioid peptide receptors. Over the last 15 years, in vivo pharmacology and genetic models have allowed significant advances in the understanding of this role. In this review, we will focus on the involvement of DOR in modulating different types of hippocampal- and striatal-dependent learning processes as well as motor function, motivation, and reward. Remarkably, DOR seems to play a key role in balancing hippocampal and striatal functions, with major implications for the control of cognitive performance and motor function under healthy and pathological conditions.


Subject(s)
Learning/physiology , Motivation/physiology , Receptors, Opioid, delta/physiology , Animals , Humans , Learning/drug effects , Motivation/drug effects , Receptors, Opioid, delta/biosynthesis , Receptors, Opioid, delta/drug effects , Reward
8.
Rev Neurol (Paris) ; 173(1-2): 47-54, 2017.
Article in English | MEDLINE | ID: mdl-28131535

ABSTRACT

OBJECTIVE: To determine the effects of a 1-year quality-improvement (QI) process to reduce door-to-needle (DTN) time in a secondary general hospital in which multimodal MRI screening is used before tissue plasminogen activator (tPA) administration in patients with acute ischemic stroke (AIS). METHODS: The QI process was initiated in January 2015. Patients who received intravenous (iv) tPA<4.5h after AIS onset between 26 February 2015 to 25 February 2016 (during implementation of the QI process; the "2015 cohort") were identified (n=130), and their demographic and clinical characteristics and timing metrics compared with those of patients treated by iv tPA in 2014 (the "2014 cohort", n=135). RESULTS: Of the 130 patients in the 2015 cohort, 120 (92.3%) of them were screened by MRI. The median DTN time was significantly reduced by 30% (from 84min in 2014 to 59min; P<0.003), while the proportion of treated patients with a DTN time≤60min increased from 21% to 52% (P<0.0001). Demographic and baseline characteristics did not significantly differ between cohorts, and the improvement in DTN time was associated with better outcomes after discharge (patients with a 0-2 score on the modified rankin scale: 59% in the 2015 cohort vs 42.4% in the 2014 cohort; P<0.01). During the 1-year QI process, the median DTN time decreased by 15% (from 65min in the first trimester to 55min in the last trimester; P≤0.04) with a non-significant 1.5-fold increase in the proportion of treated patients with a DTN time≤60min (from 41% to 62%; P=0.09). CONCLUSION: It is feasible to deliver tPA to patients with AIS within 60min in a general hospital, using MRI as the routine screening modality, making this QI process to reduce DTN time widely applicable to other secondary general hospitals.


Subject(s)
Brain Ischemia/diagnosis , Brain Ischemia/drug therapy , Fibrinolytic Agents/administration & dosage , Stroke/diagnosis , Stroke/drug therapy , Time-to-Treatment/standards , Administration, Intravenous , Aged , Aged, 80 and over , Emergency Medical Services/standards , Female , France , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Needles , Quality Improvement , Time Factors
9.
Int J Biol Macromol ; 87: 195-200, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26902895

ABSTRACT

Herpes simplex virus belongs to Herpesviridae family and causes infection of humans from ancient times. 4OMe-glucuronoxylans as the renewable biopolymers can be promising glycomaterials for various applications in pharmacy. Control enzymatic degradation of the native 4OMe-glucuronoxylan (GX1) followed by targeted sulfation procedure afforded a range of 4OMe-glucuronoxylan sulfates differed in the degree of sulfation (10-16%) and molecular mass (21,000-5000g/mol; GXS1>GXS2>GXS3>GXS4). Antiviral activity tests on GXS1-4 against herpes simplex virus (HSV) types 1 and 2 revealed the positive effect of all compounds against strains of herpes virus. Of them, the compounds GXS1 and GXS4 were shown to be the most active for both HSV serotypes. The antiviral activity of GXS1 and GXS4 was similar to those of heparin or dextran sulfate, used as reference compounds. It was found that GXS1 and GXS4 were active as well against Polio and dengue viruses, however, on a smaller scale. The mode of antiviral action of 4OMe-glucuronoxylan sulfates is due to inhibition of the virus binding to the cell receptors.


Subject(s)
Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Fagus/chemistry , Sulfates/chemistry , Xylans/chemistry , Xylans/pharmacology , Animals , Antiviral Agents/toxicity , Chlorocebus aethiops , Vero Cells , Viruses/drug effects , Xylans/toxicity
10.
Actas Dermosifiliogr ; 106(10): 823-9, 2015 Dec.
Article in English, Spanish | MEDLINE | ID: mdl-26381434

ABSTRACT

BACKGROUND AND OBJECTIVE: Anti-tumor necrosis factor therapy for moderate to severe psoriasis can increase the risk of active tuberculosis in patients who have latent tuberculosis infection (LTBI). The main objective of this study was to estimate the prevalence of LTBI in patients with moderate to severe plaque psoriasis being treated in dermatology clinics in Spain. MATERIAL AND METHOD: Non-interventional, cross-sectional, national epidemiological study conducted in Spain in 2011-2012. Patients with moderate to severe plaque psoriasis were included if they had undergone at least one tuberculin skin test (TST) and/or been evaluated with an interferon-γ release assay (IGRA) based on enzyme-linked immunosorbent assay (QuantiFERON(®) TB Gold In-Tube) in the 2 years preceding the study. RESULTS: Data for 440 patients were valid for analysis. In total, 97.7% of the patients had undergone a TST, with a positive result in 23%. Of the 238 patients in whom the initial result was negative, 5% converted to positive on re-testing for a booster effect. IGRA results were available for 16.8%, 20.5% of them positive. Two of the patients with positive IGRA results had a negative TST. The prevalence of LTBI in the whole sample was 26.6%. The degree of concordance between the TST and the IGRA was moderate (κ=0.516; P<.001). CONCLUSIONS: The prevalence of LTBI in this study was similar to previous estimates for Spain.


Subject(s)
Latent Tuberculosis/epidemiology , Psoriasis/epidemiology , Adult , Antirheumatic Agents/therapeutic use , BCG Vaccine , Contraindications , Cross-Sectional Studies , Emigrants and Immigrants , Female , Humans , Interferon-gamma Release Tests , Latent Tuberculosis/diagnosis , Male , Middle Aged , Prevalence , Psoriasis/drug therapy , Psoriasis/genetics , Spain/epidemiology , Tuberculin Test , Vaccination/statistics & numerical data
11.
Ann Dermatol Venereol ; 141(2): 106-10, 2014 Feb.
Article in French | MEDLINE | ID: mdl-24507204

ABSTRACT

BACKGROUND: In-transit metastases in cutaneous melanoma are common and difficult to manage. Therapy is mainly palliative. Use of topical imiquimod has been assessed for surface metastases. PATIENTS AND METHODS: We report on four patients with cutaneous melanoma metastases treated with topical imiquimod associated with carbon dioxide laser in the first two patients and with electrocoagulation in the two others. For two patients, we noted complete regression of the lesions after 15 and 18 months. For the two others, treatment was stopped after 9 to 10 months because of progression of subcutaneous metastasis and distant metastasis. DISCUSSION: Topical imiquimod is an alternative treatment used in superficial in-transit metastasis of melanoma. Its use as a monotherapy is sometimes ineffective. We elected to use combined pre-treatment with carbon dioxide laser or electrocoagulation in order to potentiate the action of imiquimod. This simple and inexpensive therapeutic strategy constitutes a palliative treatment that can allow prolonged local control of cutaneous metastasis.


Subject(s)
Aminoquinolines/therapeutic use , Antineoplastic Agents/therapeutic use , Electrocoagulation , Facial Neoplasms/secondary , Laser Therapy , Lasers, Gas , Melanoma/secondary , Skin Neoplasms/secondary , Administration, Cutaneous , Adult , Aged , Aminoquinolines/administration & dosage , Antineoplastic Agents/administration & dosage , Combined Modality Therapy , Disease Progression , Facial Neoplasms/drug therapy , Facial Neoplasms/pathology , Facial Neoplasms/surgery , Fatal Outcome , Humans , Imiquimod , Interferon-alpha/therapeutic use , Leg , Lymphatic Metastasis , Male , Melanoma/drug therapy , Melanoma/surgery , Palliative Care , Remission Induction , Sentinel Lymph Node Biopsy , Skin Neoplasms/drug therapy , Skin Neoplasms/surgery
12.
Acta Gastroenterol Belg ; 76(2): 246-50, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23898564

ABSTRACT

BACKGROUND: Liver stiffness has been claimed to be increased in patients with heart failure. AIMS: To determine the magnitude of this increase in liver stiffness, and to clarify whether it is related to the degree of heart failure or not. METHODS: Twenty-six patients were prospectively collected, and divided in groups CHF (those with compensated chronic heart failure) and AHF (those with acute decompensated heart failure). Patients underwent routine blood chemistries, pro-BNP determination, echocardiography and transient elastography during outpatient care (group CHF) or at hospital admission (group AHF). Blood chemistries, pro-BNP and transient elastography were repeated in patients in group AHF before being discharged. RESULTS: Correlation between liver stiffness and pro-BNP levels was statistically significant (Rho = 0.747, p = 0.001). Patients in group CHF had lower values of liver stiffness and pro-BNP when compared with patients in group AHF at admission. Median liver stiffness and pro-BNP values were 6.5 vs 14.4 kPa (p = 0.009) and 1511 vs 3535 pg/ml (p = 0.025) respectively. After clinical compensation, liver stiffness decreased in all patients in group AHF. Liver stiffness was 14.4 kPa at admission and 8.2 kPa at discharge (p = 0.008). Pro-BNP values also decreased from a median of 3535 pg/ml to a median of 1098 pg/ml (p = 0.025). CONCLUSIONS: Patients with heart failure have increased liver stiffness, that appears to be related with the severity of heart failure.


Subject(s)
Heart Failure/physiopathology , Liver Cirrhosis/physiopathology , Liver/physiopathology , Aged , Aged, 80 and over , Echocardiography , Elasticity , Elasticity Imaging Techniques/methods , Female , Heart Failure/blood , Heart Failure/complications , Humans , Liver Cirrhosis/diagnosis , Liver Cirrhosis/etiology , Male , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Prospective Studies
14.
Actas Dermosifiliogr ; 102(7): 537-40, 2011 Sep.
Article in Spanish | MEDLINE | ID: mdl-21435627

ABSTRACT

Drug-induced hypersensitivity syndrome is a toxicoderma with systemic involvement. Suspicion of this disorder obliges rapid withdrawal of the suspected drug, which may have been introduced up to 3 months earlier. Screening for human herpesvirus (HHV) 6 reactivation is important both for its diagnostic value and for its association with a poor prognosis. Reactivation of this virus is not a contraindication for systemic corticosteroid treatment, which should be tapered slowly in order to avoid recurrence. The possible appearance of antiphospholipid antibodies must also be considered in those cases associated with thrombocytopenia, altered hemostasis, or thrombotic events. Autoimmune disorders may also develop as a sequela of the condition. Medium-to-long-term follow-up is required even after complete resolution of the condition. We describe a new case of sulfasalazine-induced hypersensitivity syndrome associated with HHV-6 reactivation and the induction of anticardiolipin and anti-thyroid peroxidase antibodies.


Subject(s)
Antiphospholipid Syndrome/complications , Drug Eruptions/etiology , Exanthema Subitum/complications , Herpesvirus 6, Human , Sulfasalazine/adverse effects , Adult , Humans , Male
15.
Oral Microbiol Immunol ; 24(5): 353-60, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19702947

ABSTRACT

INTRODUCTION: Human beta-defensins (HBDs) are cationic, antimicrobial peptides produced by epithelial cells and involved in various aspects of the innate and acquired immune responses. They are expressed by oral tissues as constitutive and inducible genes. Recently, single nucleotide polymorphisms (SNPs) of beta-defensins have been correlated with increased susceptibility to certain diseases. Studies have reported altered expression of beta-defensins in cancers suggesting their involvement in carcinogenesis. The purpose of this study was to evaluate the regulation of HBD-1 (also published as DEFB1), HBD-2 (DEFB4) and HBD-3 (DEFB103A) (http://www.genenames.org/index.html) and HBD-1 SNPs in oral squamous cell carcinoma cell lines (OSCC) and healthy gingival keratinocytes. METHODS: beta-defensin expression was quantitatively assessed using real-time polymerase chain reactions in OSCC and control cell lines after exposure to interleukin-1beta, tumor necrosis factor-alpha, and interferon-gamma. Control data were obtained in a previous study. DNA from 19 OSCC cell lines and 44 control subjects were extracted and the HBD-1 region spanning the 5' untranslated region to the first intron was sequenced and analysed for SNP identification and distribution. RESULTS: HBD-1 and HBD-2 basal messenger RNA expression were significantly lower in OSCC. In addition, the ability to be induced was significantly reduced in OSCC for all three beta-defensins. Four HBD-1 SNPs were differentially distributed between cancer and control populations. Genotype distribution at the HBD-1 locus also suggested loss of heterozygosity in OSCC. CONCLUSIONS: The genetic variation observed in OSCC compared with that in control cell lines may account for differences in beta-defensin expression. These results suggest a putative role for beta-defensins in carcinogenesis and indicate that beta-defensins may be useful markers of OSCC.


Subject(s)
Antimicrobial Cationic Peptides/genetics , Carcinoma, Squamous Cell/genetics , Mouth Neoplasms/genetics , Polymorphism, Single Nucleotide/genetics , beta-Defensins/genetics , 5' Untranslated Regions/genetics , Cell Line, Tumor , DNA, Neoplasm/genetics , Exons/genetics , Gene Expression Regulation, Neoplastic/genetics , Gene Frequency/genetics , Genotype , Gingiva/cytology , Gingiva/metabolism , Haplotypes/genetics , Humans , Interferon-gamma/pharmacology , Interleukin-1beta/pharmacology , Introns/genetics , Keratinocytes/metabolism , Linkage Disequilibrium/genetics , Loss of Heterozygosity/genetics , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha/pharmacology
17.
Diabetologia ; 50(10): 2190-9, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17676309

ABSTRACT

AIMS/HYPOTHESIS: Uncoupling protein (UCP) 3 is a mitochondrial inner membrane protein expressed predominantly in glycolytic skeletal muscles. Its role in vivo remains poorly understood. The aim of the present work was to produce a mouse model with moderate overproduction and proper fibre-type distribution of UCP3. METHODS: Transgenic mice were created with a 16 kb region encompassing the human UCP3 gene. Mitochondrial uncoupling was investigated on permeabilised muscle fibres. Changes in body weight, adiposity and glucose or insulin tolerance were assessed in mice fed chow and high-fat diets. Indirect calorimetry was used to determine whole-body energy expenditure and substrate utilisation. RESULTS: Transgenic mice showed a twofold increase in UCP3 protein levels specifically in glycolytic muscles. Mitochondrial respiration revealed an increase of uncoupling in glycolytic but not in oxidative muscles. Transgenic mice gained less weight than wild-type littermates due to lower adipose tissue accretion when fed a high-fat diet. Animals showed a sexual dimorphism in metabolic responses. Female transgenic mice were more glucose-sensitive than wild-type animals, while male transgenic mice with high body weights had impaired glucose and insulin tolerance. Measurements of RQs in mice fed chow and high-fat diets suggested an impairment of metabolic flexibility in transgenic male mice. CONCLUSIONS/INTERPRETATION: Our data show that physiological overproduction of UCP3 in glycolytic muscles results in mitochondrial uncoupling, resistance to high-fat diet-induced obesity and sex specificity regarding insulin sensitivity and whole-body substrate utilisation.


Subject(s)
Blood Glucose/metabolism , Dietary Fats , Insulin Resistance , Ion Channels/genetics , Mitochondria, Muscle/physiology , Mitochondrial Proteins/genetics , Muscle, Skeletal/physiology , Sex Characteristics , Animals , Female , Gene Expression Regulation , Glycolysis , Male , Mice , Mice, Transgenic , RNA, Messenger/genetics , Uncoupling Protein 3
18.
Planta Med ; 72(2): 121-5, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16491446

ABSTRACT

The partially cyclized mu/nu-carrageenan 1C3, isolated from the red seaweed Gigartina skottsbergii, was previously shown to be a potent inhibitor of the in vitro replication of Herpes simplex virus types 1 (HSV-1) and 2 (HSV-2). Here the protective effect of 1C3 in a murine model of intraperitoneal ( i. p.) HSV-1 infection was evaluated. OF1 mice were i. p. infected with 5 x 10 (5) PFU of HSV-1 KOS strain, and the effects of different treatments with 1C3 were studied. When 30 mg/kg of body weight of 1C3 was administered by the i. p. route immediately after HSV-1 infection, 87.5 % survival of the animals was achieved (p < 0.005), associated with a delay in the mean day of death in 1C3-treated non-surviving mice. Animal survival was not improved when multiple doses of 1C3 were also given in the period 1 - 48 h post-infection, and no protection was afforded when treatment was started after 24 h of infection. When virus and compound were injected by different routes, i. p. and intravenous ( i. v.), respectively, a still significant protection was achieved (40 % survival, p < 0.05). No toxicity of 1C3 for the animals was recorded. The pharmacokinetic properties were analyzed after injection of 1C3 into the tail vein by monitoring of [ (3)H]-1C3 in plasma and organs and by a bioassay of the anti-HSV-1 activity remaining in serum after non-radioactive 1C3 inoculation. A very rapid disappearance of the compound from the blood was observed since only 5.9 - 0.9 % of the radioactivity of the initially administered [ (3)H]-1C3 appeared in the plasma between 5-300 minutes after administration. A transient peak of radioactivity was detected in the kidney 15 minutes after inoculation. The bioassay confirms the presence of the compound circulating in a biologically active form up to 1 hour after injection.


Subject(s)
Antiviral Agents/therapeutic use , Carrageenan/therapeutic use , Herpes Simplex/drug therapy , Phytotherapy , Rhodophyta/chemistry , Animals , Antiviral Agents/isolation & purification , Carrageenan/isolation & purification , Carrageenan/pharmacokinetics , Disease Models, Animal , Injections, Intraperitoneal , Male , Mice , Plant Preparations/therapeutic use , Tissue Distribution
19.
Antiviral Res ; 66(2-3): 103-10, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15911027

ABSTRACT

Two homogeneous sulfated polysaccharides obtained from the red seaweeds Gymnogongrus griffithsiae and Cryptonemia crenulata, the kappa/iota/nu carrageenan G3d and the dl-galactan hybrid C2S-3, were assayed for their antiviral properties against the four serotypes of dengue virus (DENV) in different host cell types. Both seaweed derivatives were selective inhibitors of DENV-2 multiplication in Vero cells with inhibitory concentration 50% (IC50) values around 1 microg/ml and selectivity indices > 1000. The compounds had a lower antiviral effect against DENV-3 (IC50 values in the range 13.9-14.2 microg/ml), an even lower effect against DENV-4 (IC50 values in the range 29.3 to > 50 microg/ml) and were totally inactive against DENV-1. With respect to the host cell, the polysulfates were inhibitors of DENV-2 and DENV-3 in the human hepatoma HepG2 and foreskin PH cells, with similar antiviral effectiveness as in Vero cells, but were totally inactive in mosquito C6/36 HT cells. Mechanistic studies demonstrated that G3d and C2S-3 were active DENV-2 inhibitors only when added together with the virus or early after infection, and both initial processes of virus adsorption and internalization are the main targets of these compounds. Therefore, the variations in antiviral activity of the polysaccharides depending on the viral serotype and the host cell may be ascribed to differences in the virus-cell interaction leading to virus entry.


Subject(s)
Antiviral Agents/pharmacology , Dengue Virus/drug effects , Polysaccharides/pharmacology , Seaweed/chemistry , Animals , Antiviral Agents/chemistry , Antiviral Agents/isolation & purification , Chlorocebus aethiops , Galactans/isolation & purification , Galactans/pharmacology , Microbial Sensitivity Tests , Polysaccharides/metabolism , Sulfates/metabolism , Vero Cells
20.
Antivir Chem Chemother ; 13(2): 83-9, 2002 Mar.
Article in English | MEDLINE | ID: mdl-12238532

ABSTRACT

A novel series of DL-galactan hybrids extracted from the red seaweed Gymnogongrus torulosus, was evaluated for its in vitro antiviral properties against herpes simplex virus type 2 (HSV-2) and dengue virus 2 (DEN-2). These compounds were very active against both viruses with inhibitory concentration 50% (IC50) values in the range 0.6-16 microg/ml for HSV-2 and 0.19-1.7 microg/ml for DEN-2, respectively, as determined in a virus plaque reduction assay in Vero cells. The DL-galactans lacked of cytotoxic effects, on stationary as well as on actively dividing cells, and anticoagulant properties. Some of the compounds showed a variable level of direct inactivating effect on both virions, with virucidal concentration 50% values exceeding the IC50s obtained by plaque reduction assay. Full inhibitory activity was achieved when the galactans were present during virus adsorption period, suggesting that the mode of action of these compounds is an interference in the binding of the surface envelope glycoprotein with the cell receptor.


Subject(s)
Antiviral Agents/pharmacology , Dengue Virus/drug effects , Galactans/pharmacology , Herpesvirus 2, Human/drug effects , Seaweed/chemistry , Adsorption/drug effects , Animals , Antiviral Agents/isolation & purification , Antiviral Agents/toxicity , Chlorocebus aethiops , Galactans/isolation & purification , Galactans/toxicity , Inhibitory Concentration 50 , Simplexvirus/drug effects , Thrombin Time , Vero Cells , Viral Envelope Proteins/antagonists & inhibitors
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