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1.
BMC Infect Dis ; 20(1): 850, 2020 Nov 16.
Article in English | MEDLINE | ID: mdl-33198667

ABSTRACT

BACKGROUND: The objective of the study was to describe the evolution of chronic non-AIDS related diseases and their risk factors, in patients living with HIV (PLHIV) in the French ANRS CO3 Aquitaine prospective cohort, observed both in 2004 and in 2014 in order to improve long-term healthcare management. METHODS: The ANRS CO3 Aquitaine cohort prospectively collects epidemiological, clinical, biological and therapeutic data on PLHIV in the French Aquitaine region. Two cross sectional analyses were performed in 2004 and 2014, to investigate the patient characteristics, HIV RNA, CD4 counts and prevalence of some common comorbidities and treatment. RESULTS: 2138 PLHIV (71% male, median age 52.2 years in 2014) were identified for inclusion in the study, including participants who were registered in the cohort with at least one hospital visit recorded in both 2004 and 2014. Significant increases in the prevalence of diagnosed chronic kidney disease (CKD), bone fractures, cardiovascular events (CVE), hypertension, diabetes and dyslipidaemia, as well as an increase in treatment or prevention for these conditions (statins, clopidogrel, aspirin) were observed. It was also reflected in the increase in the proportion of patients in the "high" or "very high" risk groups of the disease risk scores for CKD, CVE and bone fracture score. CONCLUSIONS: Between 2004 and 2014, the aging PLHIV population identified in the French ANRS CO3 Aquitaine prospective cohort experienced an overall higher prevalence of non-HIV related comorbidities, including CKD and CVD. Long-term healthcare management and long-term health outcomes could be improved for PLHIV by: careful HIV management according to current recommendations with optimal selection of antiretrovirals, and early management of comorbidities through recommended lifestyle improvements and preventative measures.


Subject(s)
Diabetes Mellitus/epidemiology , Dyslipidemias/epidemiology , Fractures, Bone/epidemiology , HIV Infections/epidemiology , HIV-1/genetics , Hypertension/epidemiology , Renal Insufficiency, Chronic/epidemiology , Adult , Aging , Anti-HIV Agents/therapeutic use , CD4 Lymphocyte Count , Comorbidity/trends , Cross-Sectional Studies , Female , France/epidemiology , HIV Infections/diagnosis , HIV Infections/drug therapy , HIV Infections/virology , Humans , Male , Middle Aged , Prevalence , Prospective Studies , RNA, Viral/analysis , Risk Factors
2.
Molecules ; 24(9)2019 May 06.
Article in English | MEDLINE | ID: mdl-31064153

ABSTRACT

Inhibiting the interaction of neuropilin-1 (NRP-1) with vascular endothelial growth factor (VEGF) has become an interesting mechanism for potential anticancer therapies. In our previous works, we have obtained several submicromolar inhibitors of this interaction, including branched pentapeptides of general structure Lys(Har)-Xxx-Xxx-Arg. With the intent to improve the proteolytic stability of our inhibitors, we turned our attention to 1,4-disubstituted 1,2,3-triazoles as peptide bond isosteres. In the present contribution, we report the synthesis of 23 novel triazolopeptides along with their inhibitory activity. The compounds were synthesized using typical peptide chemistry methods, but with a conversion of amine into azide completely on solid support. The inhibitory activity of the synthesized derivatives spans from 9.2% to 58.1% at 10 µM concentration (the best compound Lys(Har)-GlyΨ[Trl]GlyΨ[Trl]Arg, 3, IC50 = 8.39 µM). Synthesized peptidotriazoles were tested for stability in human plasma and showed remarkable resistance toward proteolysis, with half-life times far exceeding 48 h. In vitro cell survival test resulted in no significant impact on bone marrow derived murine cells 32D viability. By means of molecular dynamics, we were able to propose a binding mode for compound 3 and discuss the observed structure-activity relationships.


Subject(s)
Angiogenesis Inhibitors/chemistry , Neuropilin-1/antagonists & inhibitors , Peptides/chemistry , Triazoles/chemistry , Vascular Endothelial Growth Factors/antagonists & inhibitors , Amino Acid Sequence , Amino Acids/chemistry , Angiogenesis Inhibitors/pharmacology , Animals , Bone Marrow Cells , Cell Survival/drug effects , Chromatography, High Pressure Liquid/methods , Click Chemistry/methods , Humans , Mice , Molecular Dynamics Simulation , Molecular Structure , Peptides/pharmacology , Protein Binding , Proteolysis , Solid-Phase Synthesis Techniques/methods , Structure-Activity Relationship , Tandem Mass Spectrometry/methods , Triazoles/pharmacology
3.
Eur J Med Chem ; 158: 453-462, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-30241012

ABSTRACT

The demonstrated involvement of VEGF165/NRP-1 complex in pathological angiogenesis has catalyzed interest in blocking this interaction to combat angiogenesis dependent diseases. It was shown before that Lys-Pro-Pro-Arg is a fairly strong inhibitor of the VEGF165/NRP-1 interaction. Our current findings suggest that the side chain elongation of the Lys1 by branching it with additional homoarginine (Har) residue, to obtain Lys(Har)-Pro-Pro-Arg, allows more effective inhibition. Moreover, increasing the flexibility of the middle part of molecule, in particular with simultaneous introduction of additional interacting elements at the second or third position, produced compounds up to 30-fold more active (IC50 = 0.2 µM) than the heptapeptide ATWLPPR (A7R) which is one of the first peptide known as an effective antagonist of the VEGF165 binding to NRP-1 and in vivo decreases breast cancer angiogenesis and growth. Herein, we present also the structure-activity study of Lys(Har)-Pro-Pro-Arg, discussing the design, synthesis, inhibitory activity, proteolytic stability and molecular modeling of the prepared derivatives. For two of the most active analogs the high proteolytic stability was also observed. These studies provide the next step for elucidating the optimal structure of the small peptidic inhibitors of VEGF165/NRP-1 interaction that could serve as research tools or be prospective drug candidates.


Subject(s)
Drug Design , Neuropilin-1/metabolism , Oligopeptides/chemistry , Oligopeptides/pharmacology , Protein Interaction Maps/drug effects , Vascular Endothelial Growth Factor A/metabolism , Amino Acid Sequence , Angiogenesis Inhibitors/blood , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/metabolism , Angiogenesis Inhibitors/pharmacology , Humans , Molecular Docking Simulation , Oligopeptides/blood , Oligopeptides/metabolism , Protein Binding/drug effects
4.
Peptides ; 94: 25-32, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28627371

ABSTRACT

Neuropilin-1 is considered as one of the key receptors responsible for signaling pathways involved in pathological angiogenesis necessary for tumor progression, therefore targeting of VEGF165 binding to NRP-1 could be a relevant strategy for antiangiogenic treatment. It was shown before that the VEGF165/NRP-1 interaction can be inhibited by short tetrapeptides with K/RXXR sequence. Here, we present a structure-activity relationship study of the systematic optimization of amino acid residues in positions 1-3 in the above tetrapeptides. All the 13 synthesized analogs possessed C-terminal arginine that is a necessary element for interaction with NRP-1. The obtained results of the inhibitory activity and modeling by molecular dynamics indicate that simultaneous interactions of the basic amino acid residues in position 1 and 4 (Arg) with Neuropilin-1 are crucial and their cooperation strongly affects the inhibitory activity. In addition, the binding strength is modulated by the flexibility of the peptide backbone (in the central part of the peptide), and the nature of the side chain of the amino acids at the second or third position. A dramatic decrease in the activity to the receptor is observed in flexible derivatives that are missing proline residues. The results described in this paper should prove useful for future studies aimed at establishing the best pharmacophore for inhibitors of VEGF165 binding to NRP-1.


Subject(s)
Neuropilin-1/agonists , Oligopeptides/pharmacology , Vascular Endothelial Growth Factor A/metabolism , Angiogenesis Inhibitors/pharmacology , Animals , Humans , Molecular Dynamics Simulation , Neuropilin-1/metabolism , Rats , Structure-Activity Relationship
5.
J Pept Sci ; 23(6): 445-454, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28466607

ABSTRACT

Neuropilin-1 has been found to be overexpressed in several kinds of malignant tumors, and it is postulated that its interaction with the vascular endothelial growth factor 165 leads to progression of tumor vascularization and growth. Several analogues (KxxR) with various conformational latitudes have been synthesized and found as inhibitors of NRP-1. Detailed insight provided by molecular dynamics simulation allowed forming a clear relationship between flexibility of xx part of the molecule and its inhibitory activity.


Subject(s)
Neuropilin-1/antagonists & inhibitors , Oligopeptides/pharmacology , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Binding Sites/drug effects , Dose-Response Relationship, Drug , Humans , Models, Molecular , Neuropilin-1/chemistry , Oligopeptides/chemical synthesis , Oligopeptides/chemistry , Protein Conformation , Structure-Activity Relationship , Vascular Endothelial Growth Factor A/chemistry
6.
J Nanopart Res ; 19(5): 160, 2017.
Article in English | MEDLINE | ID: mdl-28503085

ABSTRACT

Superparamagnetic iron oxide-based nanoparticles (SPIONs) are promising carriers as targeted drug delivery vehicles, because they can be guided to their target with the help of an external magnetic field. Functionalization of nanoparticles' surface with molecules, which bind with high affinity to receptors on target tissue significantly facilitates delivery of coated nanoparticles to their targeted site. Here, we demonstrate conjugation of an antiangiogenic and antitumor peptide ATWLPPR (A7R) to SPIONs modified with sebacic acid (SPIONs-SA). Successful conjugation was confirmed by various analytical techniques (FTIR, SERS, SEM-EDS, TEM, TGA). Cell cytotoxicity studies, against two cell lines (HUVEC and MDA-MB-231) indicated that SPIONs modified with A7R reduced HUVEC cell viability at concentrations higher than 0.01 mg Fe/mL, in comparison to cells that were exposed to either the nanoparticles modified with sebacic acid or A7R peptide solely, what might be partially caused by a process of internalization.

7.
Bioorg Med Chem ; 25(2): 597-602, 2017 01 15.
Article in English | MEDLINE | ID: mdl-27889287

ABSTRACT

Inhibition of angiogenesis is one of the most promising approaches in anticancer therapy. It was recently suggested that Neuropilin-1 (NRP-1) in tumour cells may serve as a separate receptor for Vascular Endothelial Growth Factor-165 (VEGF165) which is one of the main pro-angiogenic agents in the organism. Therefore molecules inhibiting VEGF165 binding to NRP-1 could be potential candidates for new antiangiogenic and anticancer drugs. Here we present a structure-activity relationship study of the peptide H-c[Lys-Pro-Glu]-Arg-OH which showed high inhibitory effect on VEGF165/NRP-1 binding (IC50=0.18µM) in our previous study. We report the design, synthesis, in vitro assays and docking analysis of four small cyclic peptides (14-,15-membered ring) and one bigger cyclic compound (30-membered ring). Our study shows that both the ring size and configuration of amino acid residues present in the structure are crucial for high inhibitory effect.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Neovascularization, Pathologic/drug therapy , Neuropilin-1/antagonists & inhibitors , Peptides, Cyclic/pharmacology , Vascular Endothelial Growth Factors/antagonists & inhibitors , Angiogenesis Inhibitors/chemical synthesis , Angiogenesis Inhibitors/chemistry , Dose-Response Relationship, Drug , Humans , Molecular Docking Simulation , Molecular Structure , Neuropilin-1/metabolism , Peptides, Cyclic/chemical synthesis , Peptides, Cyclic/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured , Vascular Endothelial Growth Factors/metabolism
8.
Bioorg Med Chem ; 22(15): 4042-8, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-24961874

ABSTRACT

Neuropilin-1 (NRP-1), one of the most important co-receptors of vascular endothelial growth factor-A (VEGF-A), increases its angiogenic action in several chronic diseases including cancer by increasing the activity of associated tyrosine kinase receptors, VEGFR1 and VEGFR2. Binding of VEGF-A to NRP-1 plays a critical role in pathological angiogenesis and tumor progression. Today, targeting this interaction is a validated approach to fight against angiogenesis-dependent diseases. Only anti-NRP-1 antibodies, peptide and peptidomimetic drug-candidates or hits have been developed thus far. In order to identify potent orally active small organic molecules various experimental and in silico approaches can be used. Here we report, novel promising small drug-like molecules disrupting the binding of VEGF-A165 to NRP-1. We carried out structure-based virtual screening experiments using the ChemBridge compound collection on the VEGF-A165 binding pocket of NRP-1. After docking and two rounds of similarity search computations, we identified 4 compounds that inhibit the biotinylated VEGF-A165 binding to recombinant NRP-1 with Ki of about 10 µM. These compounds contain a common chlorobenzyloxy alkyloxy halogenobenzyl amine scaffold that can serve as a base for further development of new NRP-1 inhibitors.


Subject(s)
Neuropilin-1/metabolism , Vascular Endothelial Growth Factor A/metabolism , Amines/chemistry , Amines/metabolism , Binding Sites , Drug Evaluation, Preclinical , Molecular Docking Simulation , Neuropilin-1/antagonists & inhibitors , Neuropilin-1/genetics , Protein Binding , Protein Interaction Domains and Motifs , Protein Structure, Tertiary , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Structure-Activity Relationship , Vascular Endothelial Growth Factor A/antagonists & inhibitors
9.
Peptides ; 28(12): 2397-402, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17983687

ABSTRACT

Heptapeptide ATWLPPR (A7R), identified in our laboratory by screening a mutated phage library, was shown to bind specifically to neuropilin-1 (NRP-1) and then to selectively inhibit VEGF(165) binding to this receptor. In vivo, treatment with A7R resulted in decreasing breast cancer angiogenesis and growth. The present work is focused on structural characterization of A7R. Analogs of the peptide, obtained by substitution of each amino acid with alanine (alanine-scanning) or by amino acid deletion, have been systematically assayed to determine the relative importance of the side chains of each residue with respect to the inhibitory effect of A7R on VEGF(165) binding to NRP-1. We show here the importance of the C-terminal sequence LPPR and particularly the key role of C-terminal arginine. In solution, A7R displays significant secondary structure of the backbone adopting an extended conformation. However, the functional groups of arginine are very flexible in the absence of NRP-1 pointing to an induced fit upon binding to the receptor. A MD trajectory of the A7R/NRP-1 complex in explicit water, based on the recent tuftsin/NRP-1 crystal structure, has revealed the hydrogen-bonding network that contributes to A7R's binding activity.


Subject(s)
Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/pharmacology , Neuropilin-1/metabolism , Oligopeptides/chemistry , Oligopeptides/pharmacology , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Amino Acid Sequence , Animals , In Vitro Techniques , Models, Molecular , Multiprotein Complexes , Protein Binding , Protein Conformation , Rats , Recombinant Proteins/metabolism , Structure-Activity Relationship , Thermodynamics , Vascular Endothelial Growth Factor A/metabolism
10.
J Biol Chem ; 281(49): 37844-52, 2006 Dec 08.
Article in English | MEDLINE | ID: mdl-17028197

ABSTRACT

Therapeutic induction of angiogenesis is a potential treatment for chronic ischemia. Heparan sulfate proteoglycans are known to play an important role by their interactions with proangiogenic growth factors such as vascular endothelial growth factor (VEGF). Low molecular weight fucoidan (LMWF), a sulfated polysaccharide from brown seaweeds that mimic some biological activities of heparin, has been shown recently to promote revascularization in rat critical hindlimb ischemia. In this report, we first used cultured human endothelial cells (ECs) to investigate the possible ability of LMWF to enhance the actions of VEGF(165). Data showed that LMWF greatly enhances EC tube formation in growth factor reduced matrigel. LMWF is a strong enhancer of VEGF(165)-induced EC chemotaxis, but not proliferation. In addition, LMWF has no effect on VEGF(121)-induced EC migration, a VEGF isoform that does not bind to heparan sulfate proteoglycans. Then, with binding studies using (125)I-VEGF(165), we observed that LMWF enhances the binding of VEGF(165) to recombinant VEGFR-2 and Neuropilin-1 (NRP1), but not to VEGFR-1. Surface plasmon resonance analysis showed that LMWF binds with high affinity to VEGF(165) (1.2 nm) and its receptors (5-20 nm), but not to VEGF(121). Pre-injection of LMWF on immobilized receptors shows that VEGF(165) has the highest affinity for VEGFR-2 and NRP1, as compared with VEGFR-1. Overall, the effects of LMWF were much more pronounced than those of LMW heparin. These findings suggested an efficient mechanism of action of LMWF by promoting VEGF(165) binding to VEGFR-2 and NRP1 on ECs that could help in stimulating therapeutic revascularization.


Subject(s)
Endothelial Cells/drug effects , Endothelial Cells/physiology , Neuropilin-1/metabolism , Polysaccharides/pharmacology , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor A/pharmacology , Vascular Endothelial Growth Factor Receptor-2/metabolism , Animals , Cell Movement/drug effects , Cell Movement/physiology , Cells, Cultured , Humans , Molecular Weight , Neovascularization, Physiologic/drug effects , Neuropilin-1/genetics , Polysaccharides/chemistry , Protein Binding , Rats , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor Receptor-2/genetics
11.
Life Sci ; 79(25): 2370-81, 2006 Nov 17.
Article in English | MEDLINE | ID: mdl-16959272

ABSTRACT

Neuropilin-1 (NRP-1), a non-tyrosine kinase receptor of vascular endothelial growth factor-165 (VEGF165), was found expressed on endothelial and some tumor cells. Since its overexpression is correlated with tumor angiogenesis and progression, the targeting of NRP-1 could be a potential anti-cancer strategy. To explore this hypothesis, we identified a peptide inhibiting the VEGF165 binding to NRP-1 and we tested whether it was able to inhibit tumor growth and angiogenesis. To prove the target of peptide action, we assessed its effects on binding of radiolabeled VEGF165 to recombinant receptors and to cultured cells expressing only VEGFR-2 (KDR) or NRP-1. Antiangiogenic activity of the peptide was tested in vitro in tubulogenesis assays and in vivo in nude mice xenotransplanted in fat-pad with breast cancer MDA-MB-231 cells. Tumor volumes, vascularity and proliferation indices were determined. The selected peptide, ATWLPPR, inhibited the VEGF165 binding to NRP-1 but not to tyrosine kinase receptors, VEGFR-1 (flt-1) and KDR; nor did it bind to heparin. It diminished the VEGF-induced human umbilical vein endothelial cell proliferation and tubular formation on Matrigel and in co-culture with fibroblasts. Administration of ATWLPPR to nude mice inhibited the growth of MDA-MB-231 xenografts, and reduced blood vessel density and endothelial cell area but did not alter the proliferation indices of the tumor. In conclusion, ATWLPPR, a previously identified KDR-interacting peptide, was shown to inhibit the VEGF165 interactions with NRP-1 but not with KDR and to decrease the tumor angiogenesis and growth, thus validating, in vivo, NRP-1 as a possible target for antiangiogenic and antitumor agents.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antineoplastic Agents/therapeutic use , Mammary Neoplasms, Experimental/drug therapy , Neuropilin-1/metabolism , Peptide Fragments/therapeutic use , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Animals , Blotting, Western , CHO Cells , Cells, Cultured , Coculture Techniques , Cricetinae , Cross-Linking Reagents , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Female , Fibroblasts/cytology , Fibroblasts/metabolism , Humans , Immunoenzyme Techniques , Iodine Radioisotopes , Mammary Neoplasms, Experimental/blood supply , Mammary Neoplasms, Experimental/metabolism , Mice , Mice, Nude , Neovascularization, Pathologic/drug therapy , Protein Binding , Umbilical Veins , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-1/antagonists & inhibitors , Vascular Endothelial Growth Factor Receptor-1/metabolism , Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors , Vascular Endothelial Growth Factor Receptor-2/metabolism , Xenograft Model Antitumor Assays
12.
Rev Neurol (Paris) ; 162(1): 62-70, 2006 Jan.
Article in French | MEDLINE | ID: mdl-16446624

ABSTRACT

The tremendous progress achieved during the last few years with the use of highly active antiretroviral therapy in suppressing HIV replication together with improvements in immunity have been tempered by a growing number of new adverse effects. Mitochondrial toxicity is one aspect of these long-term toxicities of antiretroviral drugs, with the role of nucleoside analogs particularly underlined. Some cases of impaired mitochondrial function have been clearly identified, such as pancreatitis due to didanosine, neuropathy due to zalcitabine, myopathy due to zidovudine, and lactic acidosis due to stavudine. These mitochondrial toxicities can affect several organs, presenting different patterns of symptoms: from asymptomatic to states with few symptoms despite huge metabolic abnormalities whose prognosis is immediately life-threatening. Beyond the inhibition of DNA polymerase gamma using nucleoside analogs, responsible for decreasing mitochondrial DNA in certain targeted organs, it appears that several physiopathologic mechanisms interact to explain this observed toxicity, HIV itself plays a role, and the underlying genetic pool needs to be better identified. Such cases mean that, it is imperative to avoid cumulated toxicities caused by associated treatments. With serious cases, or persistent symptoms despite discontinuing the nucleoside analogs responsible for such toxicity, one must propose vitamins, mitochondrial co-factors, or anti-oxidants. However, the future lies in the use of potent, less toxic nucleoside analogs, and in developing compounds belonging to other classes of antiretrovirals.


Subject(s)
Anti-HIV Agents/adverse effects , HIV Infections/complications , Mitochondrial Diseases/chemically induced , Acidosis, Lactic/etiology , Adult , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use , Antimetabolites/adverse effects , Antioxidants/therapeutic use , Antiretroviral Therapy, Highly Active/adverse effects , Child , Child, Preschool , Fatty Liver/etiology , HIV Infections/drug therapy , HIV-Associated Lipodystrophy Syndrome/chemically induced , HIV-Associated Lipodystrophy Syndrome/etiology , Hematologic Diseases/etiology , Humans , Infant , Interferon-alpha/therapeutic use , Kidney Diseases/etiology , Lactates/blood , Male , Mitochondria/drug effects , Mitochondrial Diseases/complications , Mitochondrial Diseases/diagnosis , Mitochondrial Diseases/drug therapy , Myositis/etiology , Nucleosides/adverse effects , Pancreatitis/etiology , Peripheral Nervous System Diseases/etiology
13.
HIV Med ; 7(3): 140-5, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16494627

ABSTRACT

OBJECTIVES: To determine the incidence rate and risk factors for loss to follow-up (LFU) in HIV-infected individuals. METHODS: We estimated the incidence rate of LFU in 1756 HIV-infected patients enrolled in the Tourcoing Clinical Cohort from January 1985 to January 1998. We then investigated potential LFU risk factors at inclusion through a case-control study. Cases were 209 patients who had attended neither our clinic nor another HIV clinic for at least 1 year. Controls were 209 patients randomly selected from the group of HIV-infected patients followed up regularly. RESULTS: The incidence of LFU was estimated at 4.3 per 100 person-years [95% confidence interval (CI) 3.7-4.9]. Independent risk factors for LFU were (i) year of enrolment before 1993 [odds ratio (OR) 6.7; 95% CI 2.7-16.5 versus after 1997]; (ii) year of enrolment between 1993 and 1997 (OR 5.1; 95% CI 2.0-13.0 versus after 1997); (iii) age<30 years (OR 1.8; 95% CI 1.0-3.5 versus >40 years); (iv) injecting drug use (OR 5.3; 95% CI 2.7-10.5 versus men who have sex with men); (v) homelessness and/or illegal immigrant status (OR 2.2; 95% CI 1.0-4.9); and (vi) lack of a primary care provider (OR 6.0; 95% CI 2.4-15.1). A history of an AIDS-defining illness (OR 0.3; 95% CI 0.2-0.6) and a history of psychiatric disease (OR 0.4; 95% CI 0.3-0.8) were both associated with a decreased risk of LFU. CONCLUSIONS: This study assessed the sociodemographic, clinical and behavioural characteristics associated with LFU in HIV-infected patients. The findings of this study may allow clinicians to identify patients at risk of LFU, so that appropriate interventions may be initiated.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV-1 , Patient Dropouts , Adult , Age Factors , Case-Control Studies , Emigration and Immigration , Ethnicity , Female , France , HIV Infections/psychology , Homosexuality , Humans , Incidence , Male , Odds Ratio , Risk Factors , Social Class , Time Factors
14.
Int J Oncol ; 28(2): 457-62, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16391801

ABSTRACT

A current target of cancer gene therapy is tumour vasculature. We present a gene-directed enzyme prodrug therapy (GDEPT) approach to target tumours in vivo by modifying endothelial cells (ECs) with the Escherichia coli nitroreductase (ntr) gene. Firstly, we isolated two ntr-transfected clones of the human umbilical vein endothelial cell line (HUV-EC-C/ntr+) that showed a differential sensitivity in vitro to the prodrug, dinitroaziridinylbenzamide (CB1954), with respect to untransfected HUV-EC-C cells (HUV-EC-C/ntr-). Then, these cells were injected subcutaneously into nude mice, either in association with the murine melanoma cell line, B16-F10 ('co-injected' groups), or into tumour-bearing animals ('post-injected' groups). After intratumoural injection, we demonstrated, using PCR analysis, that human ECs resided in the site of the injection without spreading to other organs, such as the liver or lung. After the treatment of mice with CB1954, we observed a prolonged survival of animals carrying the HUV-EC-C/ntr+ clones with respect to control animals injected with HUV-EC-C/ntr- cells. Significant differences in tumour growth were also observed and, after immuno-histological analysis, tumours carrying HUV-EC-C/ntr+ clones showed large areas of tumour necrosis, probably due to tumour ischemia, as well as the presence of major histocompatibility complex class-II (MHC-II) positive cells. Collectively, our data indicate that targeting of the tumour vasculature by this GDEPT strategy may be an efficient approach for cancer treatment in vivo, depending on two possible bystander mechanisms based on tumour ischemia and immune cell activation.


Subject(s)
Drug Delivery Systems , Endothelial Cells/metabolism , Melanoma, Experimental/blood supply , Nitroreductases/genetics , Animals , Antineoplastic Agents/pharmacology , Aziridines/pharmacology , Bystander Effect , Cell Survival , Cells, Cultured , Dose-Response Relationship, Drug , Endothelium, Vascular/drug effects , Escherichia coli/genetics , Genetic Therapy , Humans , Melanoma, Experimental/prevention & control , Mice , Mice, Nude , Neoplasm Transplantation , Neovascularization, Pathologic/prevention & control , Nitroreductases/metabolism , Prodrugs/pharmacology , Transfection
15.
Med Mal Infect ; 35(7-8): 407-10, 2005.
Article in French | MEDLINE | ID: mdl-16139459

ABSTRACT

OBJECTIVE: The Nadis electronic medical patient record allows real time constitution of a database including the clinical, therapeutic, biological, and epidemiological features of HIV-positive patients. METHODS: Data concerning HIV-infected patients followed-up in 6 French University Hospitals was collected. Data quality was assessed on a regular basis in each center. RESULTS: The 6 first University hospitals using Nadis agreed to group their data on March 15, 2004, concerning 6236 patients having consulted at least once in the previous year. Among these, 29% were female patients, 80% were under treatment on March 15, 2004, 9% were off treatment, 29% were co-infected by hepatitis B or C virus, 57% had an undetectable viral load, 15% of the treated patients were in a worrying immunovirological situation, 358 were diagnosed HIV-positive in 2003. 35% of these "new patients" were women, the mode of infection was sexual in 80%, 45% were under treatment on March 15, 04. This recent data allowed us to have an accurate assessment of this population's management in 2004.


Subject(s)
HIV Infections/epidemiology , Medical Records Systems, Computerized , Adult , Anti-HIV Agents/therapeutic use , Cohort Studies , Comorbidity , Databases, Factual , Disease Transmission, Infectious , Female , Follow-Up Studies , France/epidemiology , HIV Infections/drug therapy , HIV Infections/transmission , Hepatitis B/epidemiology , Hepatitis C/epidemiology , Hospitals, University/statistics & numerical data , Humans , Male , Middle Aged , Quality Control , Sexual Behavior , Substance Abuse, Intravenous/epidemiology , Transfusion Reaction , Viral Load
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 60(14): 3353-60, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15561620

ABSTRACT

A near-infrared diode laser-based spectrometer has been designed and built for the remote sensing of vehicle emissions. It detects carbon monoxide and carbon dioxide absorptions around 1580 nm and can provide the ratio CO/CO(2) for vehicle exhaust studies. The system is battery powered and is designed to sit unobtrusively at the side of the road. The optics and electronics of the system is described and preliminary results are presented from field trials. Extensions to the spectrometer in terms of sensitivity by detection of the more intense first overtone of carbon monoxide around 2320 nm are described, in addition to further work on other species of interest.


Subject(s)
Lasers , Spectroscopy, Near-Infrared/instrumentation , Vehicle Emissions/analysis , Carbon Dioxide/analysis , Carbon Monoxide/analysis , Methane/analysis , Time Factors
17.
Nucl Med Biol ; 31(5): 575-81, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15219275

ABSTRACT

Neuropilins (NRP) are receptors of angiogenic vascular endothelial growth factor (VEGF). Their overexpression was correlated with tumor angiogenesis and growth suggesting that their specific targeting could provide a new marker of tumor progression. Here, we observed in vitro that new (99m)Tc-labeled derivative of anti-VEGF heptapeptide, ATWLPPR, binds to NRP1 but not to NRP2. Our radiotracer is stable up to 24 h in human serum and in cysteine challenge. But, its too low affinity and too fast extraction indicate further improvement to give a successful imaging of tumor in vivo.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/metabolism , Neuropilin-1/metabolism , Peptides/pharmacokinetics , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/metabolism , Animals , Cell Line, Tumor , Female , Humans , Isotope Labeling/methods , Male , Metabolic Clearance Rate , Mice , Mice, Nude , Neuropilin-1/chemistry , Organ Specificity , Peptides/chemical synthesis , Peptides/chemistry , Protein Binding , Radionuclide Imaging , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/pharmacokinetics , Rats , Reproducibility of Results , Sensitivity and Specificity , Technetium/chemistry , Technetium/pharmacology , Tissue Distribution
19.
Biochem Biophys Res Commun ; 311(4): 822-8, 2003 Nov 28.
Article in English | MEDLINE | ID: mdl-14623255

ABSTRACT

Tumor cells are elusive targets for standard anticancer chemotherapy due to their heterogeneity and genetic instability. On the other hand, proliferating host endothelial cells (ECs) are genetically stable and have a low mutational rate. Thus, antiangiogenic therapy directed against tumor's ECs should, in principle, improve the efficacy of antitumor therapy by inducing little or no drug resistance. Here we present a gene-directed enzyme prodrug therapy (GDEPT) strategy for targeting the tumor vasculature, using the Escherichia coli nitroreductase (ntr) gene delivery associated with the treatment with the prodrug CB1954. In a first time we demonstrated the ability of the ntr/CB1954 system to induce an apoptotic-mediated cell death on monolayer cultures of human umbilical vein ECs (HUV-EC-C). Then, when ntr-transfected HUV-EC-C cells (HUV-EC-C/ntr(+)) were associated in a three-dimensional (3-D) multicellular nodule model with untransfected B16-F10 murine melanoma cell line, we observed a CB1954-mediated bystander cell killing effect from endothelial to neighboring melanoma cells. To our knowledge, this is the first report indicating that GDEPT-based antiangiogenic targeting may be an effective approach for cancer treatment relied on the spreading of the bystander effect from endothelial to tumor cells.


Subject(s)
Aziridines , Bystander Effect , Endothelium, Vascular , Genetic Therapy , Melanoma , Nitroreductases , Animals , Humans , Mice , 3T3 Cells , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Apoptosis/genetics , Aziridines/administration & dosage , Bystander Effect/genetics , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , Coculture Techniques/methods , Dose-Response Relationship, Drug , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Escherichia coli/enzymology , Escherichia coli/genetics , Genetic Therapy/methods , Melanoma/genetics , Melanoma/metabolism , Melanoma/pathology , Nitroreductases/genetics , Nitroreductases/metabolism , Prodrugs/administration & dosage , Umbilical Veins/drug effects , Umbilical Veins/metabolism
20.
Clin Infect Dis ; 36(1): 86-96, 2003 Jan 01.
Article in English | MEDLINE | ID: mdl-12491207

ABSTRACT

A simulation model of human immunodeficiency virus (HIV) disease, which incorporated French data on the progression of HIV disease in the absence of antiretroviral therapy and on cost, was used to determine the clinical impact and cost-effectiveness of different strategies for the prevention of opportunistic infections in French patients who receive highly active antiretroviral therapy (HAART). Compared with use of no prophylaxis, use of trimethoprim-sulfamethoxazole (TMP-SMZ) increased per-person lifetime costs from euro 185,600 to euro 187,900 and quality-adjusted life expectancy from 112.2 to 113.7 months, for an incremental cost-effectiveness ratio of euro 18,700 per quality-adjusted life-year (euro/QALY) gained. Compared with use of TMP-SMZ alone, use of TMP-SMZ plus azithromycin cost euro 23,900/QALY gained; adding fluconazole cost an additional euro 54,500/QALY gained. All strategies that included oral ganciclovir had cost-effectiveness ratios that exceeded euro 100,000/QALY gained. In the era of HAART, on the basis of French data, prophylaxis against Pneumocystis carinii pneumonia, toxoplasmic encephalitis, and Mycobacterium avium complex bacteremia is cost-effective. Prophylaxis against fungal and cytomegalovirus infections is less cost-effective than are other therapeutic options for HIV disease and should remain of lower priority.


Subject(s)
AIDS-Related Opportunistic Infections/economics , Chemoprevention/economics , AIDS-Related Opportunistic Infections/prevention & control , Antiretroviral Therapy, Highly Active/economics , Chemoprevention/standards , Cost-Benefit Analysis , France , Guidelines as Topic , HIV Infections/drug therapy , Humans , Life Expectancy , Quality of Life
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