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1.
Clin Exp Immunol ; 211(3): 269-279, 2023 03 24.
Article in English | MEDLINE | ID: mdl-36622786

ABSTRACT

Cohorts of healthy younger adults (18-50yrs) and healthy older adults (60-75yrs) were immunized intramuscularly or intranasally with an adenovirus-vectored RSV vaccine (PanAd3-RSV) as a prime dose and boosted with PanAd3-RSV or a poxvirus-vectored vaccine (MVA-RSV) encoding the same insert. Whole blood gene expression was measured at baseline, 3- and 7-days post vaccination. Intramuscular prime vaccination with PanAd3-RSV induced differential expression of 643 genes (DEGs, FDR < 0.05). Intranasal prime vaccination with PanAd3-RSV did not induce any differentially expressed genes (DEGs) in blood samples at 3 days post vaccination. Intranasally primed participants showed greater numbers of DEGS on boosting than intramuscularly primed participants. The most highly enriched biological processes related to DEGs after both prime and boost vaccination were type-1 interferon related pathways, lymphocytic and humoral immune responses.


Subject(s)
Pan troglodytes , Transcriptome , Animals , Humans , Aged , Pan troglodytes/genetics , Immunization, Secondary , Genetic Vectors/genetics , Adenoviridae/genetics , Antibodies, Viral
2.
Vaccine ; 36(41): 6183-6190, 2018 10 01.
Article in English | MEDLINE | ID: mdl-30177258

ABSTRACT

BACKGROUND: Respiratory syncytial virus (RSV) causes respiratory disease throughout life. Here we report differences in naturally acquired immunity with age and presumed exposure. METHODS: A longitudinal, non-interventional, observational study was performed in healthy adults (20 paediatric healthcare workers and 10 non-healthcare workers), children (10 aged 3-6 years) and infants (5 aged 2-4 months and 20 aged 6-12 months). Blood samples were analysed for RSV-neutralising antibody titre, F/Ga/Gb-specific antibody titres, F-specific IgG/IgA memory B-cell frequencies and T-cell production of IFNγ, IL-4, IL-13 and IL-17. RESULTS: Serum G-specific antibody titres were significantly lower in infants and children than adults. However, serum titres of F-specific and RSV-neutralising antibody and IFNγ-producing T-cell frequencies were low or absent in the infants, but comparable between children and adults. Interestingly, F-specific memory IgA B-cells could not be detected in paediatric samples and in samples from non-healthcare workers, but recordable IgA memory B-cells were found in 9/18 paediatric healthcare workers and 2/8 non-healthcare workers at the end of the RSV season. These responses waned 4-6 months later. By contrast, F-specific IgG memory B-cells were detectable in samples from all adults without significant variation across time points. T-cells producing IL-4, IL-13 and IL-17 responses were not detectable in peripheral blood from a subset of volunteers. CONCLUSIONS: Repeated RSV exposure in early life generates immune responses that are inversely related to frequency of severe disease. Induction of F-specific antibody and cellular immune responses through infant vaccination might help to accelerate the development of protective immune responses at an early age. Clinicaltrials.gov reference NCT01563692 and NCT01640652.


Subject(s)
Immunity, Cellular/physiology , Immunity, Humoral/physiology , Respiratory Syncytial Virus Infections/immunology , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus, Human/immunology , Respiratory Syncytial Virus, Human/pathogenicity , Adolescent , Adult , Antibodies, Viral/immunology , B-Lymphocytes/metabolism , Child , Child, Preschool , Female , Humans , Immunologic Memory/physiology , Infant , Male , T-Lymphocytes/metabolism , Young Adult
3.
BMJ Open ; 5(10): e008748, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26510727

ABSTRACT

INTRODUCTION: Respiratory syncytial virus (RSV) infection causes respiratory disease throughout life, with infants and the elderly at risk of severe disease and death. RSV001 is a phase 1 (first-in-man), open-label, dose-escalation, clinical trial of novel genetic viral-vectored vaccine candidates PanAd3-RSV and modified vaccinia virus Ankara (MVA)-RSV. The objective of RSV001 is to characterise the (primary objective) safety and (secondary objective) immunogenicity of these vaccines in healthy younger and older adults. METHODS AND ANALYSIS: Heterologous and homologous 'prime'/boost combinations of PanAd3-RSV and single-dose MVA-RSV are evaluated in healthy adults. 40 healthy adults aged 18-50 years test one of four combinations of intramuscular (IM) or intranasal (IN) PanAd3-RSV prime and IM PanAd3 or IM MVA-RSV boost vaccination, starting at a low dose for safety. The following year an additional 30 healthy adults aged 60-75 years test either a single dose of IM MVA-RSV, one of three combinations of IN or IM PanAd3-RSV prime and PanAd3-RSV or MVA-RSV boost vaccination used in younger volunteers, and a non-vaccinated control group. Study participants are self-selected volunteers who satisfy the eligibility criteria and are assigned to study groups by sequential allocation. Safety assessment includes the daily recording of solicited and unsolicited adverse events for 1 week after vaccination, as well as visit (nursing) observations and safety bloods obtained at all scheduled attendances. Laboratory measures of RSV-specific humoral and cellular immune responses after vaccination will address the secondary end points. All study procedures are performed at the Centre for Clinical Vaccinology and Tropical Medicine (CCVTM), Oxford, UK. ETHICS AND DISSEMINATION: RSV001 has clinical trial authorisation from the Medicines and Healthcare Products Regulatory Agency (MHRA) and ethics approval from NRES Berkshire (reference 13/SC/0023). All study procedures adhere to International Conference on Harmonisation (ICH) Good Clinical Practice guidelines. The results of the trial are to be published in peer-reviewed journals, conferences and academic forums. TRIAL REGISTRATION NUMBER: NCT01805921.


Subject(s)
Adenoviruses, Simian , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Vaccines/immunology , Respiratory Syncytial Viruses , Vaccination , Vaccinia virus , Viral Proteins , Adolescent , Adult , Aged , Clinical Protocols , Female , Genetic Vectors , Humans , Male , Middle Aged , Research Design , Respiratory Syncytial Virus Infections/immunology , Respiratory Syncytial Virus Vaccines/adverse effects , Young Adult
4.
Acta Diabetol ; 51(3): 385-93, 2014.
Article in English | MEDLINE | ID: mdl-24132660

ABSTRACT

The aim of the study was to evaluate the effects of a supervised physical training added to a healthy diet-rich in either carbohydrate and fibre (CHO/fibre) or monounsaturated fatty acids (MUFA)-on postprandial dyslipidaemia, an independent cardiovascular risk factor particularly relevant in type 2 diabetes (T2D). Participants were forty-five overweight/obese subjects with T2D, of both genders, in good blood glucose control with diet or diet+metformin, with normal fasting plasma lipids. According to a parallel groups 2 × 2 factorial design, participants were randomized to an 8-week isoenergetic intervention with a CHO/fibre or a MUFA diet, with or without a supervised low-volume aerobic training programme. The main outcome of the study was the incremental area under the curve (iAUC) of lipid concentrations in the plasma chylomicron+VLDL lipoprotein fraction, isolated by preparative ultracentrifugation (NCT01025856). Body weight remained stable during the trial in all groups. Physical fitness slightly improved with training (VO2 peak, 16 ± 4 vs. 15 ± 3 ml/kg/min, M ± SD, p < 0.05). Postprandial triglyceride and cholesterol iAUCs in plasma and chylomicron+VLDL fraction decreased after the CHO/fibre diet, but increased after the MUFA diet with a significant effect for diet by two-way ANOVA (p < 0.05). The addition of exercise training to either dietary intervention did not significantly influence postprandial lipid response. A diet rich in carbohydrates and fibre reduced postprandial triglyceride-rich lipoproteins compared with a diet rich in MUFA in patients with T2D. A supervised low-volume physical training did not significantly influence these dietary effects.


Subject(s)
Diabetes Mellitus, Type 2/diet therapy , Dietary Fiber/metabolism , Exercise Therapy , Fatty Acids, Monounsaturated/metabolism , Hyperlipidemias/etiology , Aged , Blood Glucose/metabolism , Combined Modality Therapy , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/therapy , Diet , Dietary Carbohydrates/metabolism , Fatty Acids, Monounsaturated/adverse effects , Female , Humans , Hyperlipidemias/metabolism , Lipid Metabolism , Male , Middle Aged , Postprandial Period , Treatment Outcome
5.
Case Rep Obstet Gynecol ; 2013: 479698, 2013.
Article in English | MEDLINE | ID: mdl-23984132

ABSTRACT

Isolated torsion of the Fallopian tube is a rare gynecological cause of acute lower abdominal pain, and diagnosis is difficult. There are no pathognomonic symptoms; clinical, imaging, or laboratory findings. A preoperative ultrasound showing tubular adnexal masses of heterogeneous echogenicity with cystic component is often present. Diagnosis can rarely be made before operation, and laparoscopy is necessary to establish the diagnosis. Unfortunately, surgery often is performed too late for tube conservation. Isolated Fallopian tube torsion should be suspected in case of acute pelvic pain, and prompt intervention is necessary.

8.
Gut ; 55(7): 1012-9, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16484505

ABSTRACT

BACKGROUND AND AIMS: Cellular mediated immunity (CMI) is thought to play a key role in resolution of primary hepatitis C virus (HCV) infection. However, CD4+ and CD8+ T cell responses are also generated during acute infection in individuals who become chronic, suggesting that they developed a defective CMI. The aim of this study was to verify if and when such immune dysfunction is established by measuring the breadth, magnitude, function, and duration of CMI in a large cohort of subjects during the natural course of acute HCV infection. METHODS: CMI was comprehensively studied by prospective sampling of 31 HCV acutely infected subjects enrolled at the onset of infection and followed for a median period of one year. RESULTS: Our results indicated that while at the onset of acute HCV infection a measurable CMI with effector function was detected in the majority of subjects, after approximately six months less than 10% of chronically infected individuals displayed significant CMI compared with 70% of subjects who cleared the virus. We showed that progressive disappearance of HCV specific T cells from the peripheral blood of chronic patients was due to an impaired ability to proliferate that could be rescued in vitro by concomitant exposure to interleukin 2 and the antigen. CONCLUSION: Our data provide evidence of strong and multispecific T cell responses with a sustained ability to proliferate in response to antigen stimulation as reliable pharmacodynamic measures of a protective CMI during acute infection, and suggest that early impairment of proliferation may contribute to loss of T cell response and chronic HCV persistence.


Subject(s)
Hepacivirus/immunology , Hepatitis C/immunology , T-Lymphocytes/immunology , Acute Disease , Adult , Antigens, Viral/immunology , CD4-Positive T-Lymphocytes/immunology , Case-Control Studies , Cell Proliferation , Chi-Square Distribution , Cohort Studies , Female , Hepacivirus/genetics , Humans , Interferon-gamma/immunology , Interleukin-1/immunology , Male , Middle Aged , RNA, Viral/blood , Reverse Transcriptase Polymerase Chain Reaction
9.
Cir. plást. ibero-latinoam ; 31(1): 67-71, ene.-mar. 2005. ilus
Article in Es | IBECS | ID: ibc-039866

ABSTRACT

El flujo venoso reverso del colgajo sural no ha sido estudiado anteriormente con claridad. El presente estudio tiene como objetivo determinar el trayecto que sigue dicho flujo reverso. Se disecaron cincuenta extremidades pélvicas en veinticinco cadáveres, se inyectó colorante de forma retrógrada en la vena safena externa y se siguió su trayecto. Se encontró que en el 100% de las disecciones, sólo había una válvula a dos centímetros proximal al maléolo lateral, la cual se encarga de desviar el flujo invertido hacia las venas peronéas profundas (AU)


The reverse venous flow of the sural flap has not been clearly reported previously. The aim of the following study is to determine the course that this reverse flow follows. Fifty pelvic extremities of twenty – five corpses were dessected, ind, was injected in a reverse manner in the lesser saphenous vein and its course was followed. In all the corpse dissections done, only one had a valve that was located two cm proximal from the lateral melleolous, which diverts the reverse flow towards the deep peroneal veins (AU)


Subject(s)
Humans , Surgical Flaps/blood supply , Tibial Arteries/physiology , Regional Blood Flow/physiology , Leg Injuries/surgery , Sural Nerve/blood supply
10.
Gut ; 53(11): 1673-81, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15479691

ABSTRACT

BACKGROUND/AIMS: Hepatitis C virus (HCV) infection results in a high frequency of chronic disease. The aim of this study was to identify early prognostic markers of disease resolution by performing a comprehensive analysis of viral and host factors during the natural course of acute HCV infection. METHODS: The clinical course of acute hepatitis C was determined in 34 consecutive patients. Epidemiological and virological parameters, as well as cell mediated immunity (CMI) and distribution of human leukocyte antigens (HLA) alleles were analysed. RESULTS: Ten out of 34 patients experienced self-limiting infection, with most resolving patients showing fast kinetics of viral clearance: at least one negative HCV RNA test during this phase predicted a favourable outcome. Among other clinical epidemiological parameters measured, the self-limiting course was significantly associated with higher median peak bilirubin levels at the onset of disease, and with the female sex, but only the latter parameter was independently associated after multivariate analysis. No significant differences between self-limiting or chronic course were observed for the distribution of DRB1 and DQB1 alleles. HCV specific T cell response was more frequently detected during acute HCV infection, than in patients with chronic HCV disease. A significantly broader T cell response was found in patients with self-limiting infection than in those with chronic evolving acute hepatitis C. CONCLUSION: The results suggest that host related factors, in particular sex and CMI, play a crucial role in the spontaneous clearance of this virus. Most importantly, a negative HCV RNA test and broad CMI within the first month after onset of the symptoms represent very efficacious predictors of viral clearance and could thus be used as criteria in selecting candidates for early antiviral treatment.


Subject(s)
Hepacivirus/isolation & purification , Hepatitis C/immunology , T-Lymphocytes/immunology , Adult , Alleles , Female , Follow-Up Studies , Genes, MHC Class II , Genetic Predisposition to Disease , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Hepatitis C/genetics , Hepatitis C/virology , Hepatitis C Antibodies/blood , Hepatitis C, Chronic/genetics , Hepatitis C, Chronic/immunology , Histocompatibility Testing , Humans , Immunity, Cellular , Male , Middle Aged , Prognosis , RNA, Viral/blood , Remission, Spontaneous
11.
Neurosci Lett ; 367(3): 384-8, 2004 Sep 09.
Article in English | MEDLINE | ID: mdl-15337271

ABSTRACT

Developmental and psychiatric disorders, including schizophrenia, may be associated with altered cortical thickness and folding. Two studies were performed: (1) to assess cortical layering around a sulcus; cortical thickness, relative thickness of the supragranular (I-III):infragranular (IV-VI) layers, and cell density were assessed at anatomically defined points around Heschl's sulcus in tissue from 10 controls and 10 schizophrenia patients. (2) To sample sulci of contrasting prominence; sulcal depth, width, lamina thickness, and cell density from laminae II-VI were taken from various sulci within the temporal lobes from another group of 6 controls and 10 patients. Reduced cell density was found in the fundi of sulci in schizophrenia. Independent of diagnosis; increased sulcal prominence in temporal cortex accompanies reduced lamina thickness (particularly layers V and VI), deep layers show negative relationships between cell density and layer thickness, and total cortex width in Heschl's sulcus reduces by half at the bottom compared to the top. Furthermore, compared to the supragranular layers, the infragranular division is relatively thicker at the top of a gyrus, equal in the wall of the sulcus and relatively thinner at the bottom. Many effects of sulcal folding on laminar proportions in controls are similar in schizophrenia. However, cell density is less at the bottom of some sulci in the temporal lobe in schizophrenia. Sampling methods should consider that cortical folding affects cell and lamina distribution in the sampled region in a highly localised manner.


Subject(s)
Cerebral Cortex/pathology , Neurons/pathology , Schizophrenia/pathology , Aged , Analysis of Variance , Case-Control Studies , Cell Count/methods , Functional Laterality , Humans , Middle Aged , Postmortem Changes
12.
Cir. plást. ibero-latinoam ; 30(3): 175-182, jul.-sept. 2004. ilus
Article in Spanish | IBECS | ID: ibc-135642

ABSTRACT

La mamoplastía de reducción ideal es aquella que crea una mama bella, con buena proyección, que permanece por largo tiempo y con la menor cicatriz posible. En este artículo se presenta nuestra experiencia de 10 años con la técnica de mamoplastía vertical realizada por los autores sobre la base de los trabajos publicados por Lassus, Bozola y Lejour, lo que ha dado por resultado una técnica que posee las ventajas de cada una de ellas, como es el obtener mamas con mejor proyección y resultados mas duraderos, preservando la inervación e irrigación del complejo areola pezón, aun en resecciones mayores a los 1000 grs.; una cicatriz corta que posibilita utilizar bikinis peque- ños o escotes amplios, y disminuye las posibles desventajas o aspectos de pobre aceptación como son, la falta de proyección del polo superior por sobre-resección, la necesidad de liposucciónar la mama, que puede ocasionar seromas además de calcificaciones post operatorias diseminadas en el tejido que enmascarasen algún proceso oncológico. Con las modificaciones realizadas resulta además una técnica con una curva de aprendizaje menos azarosa (AU)


All plastic surgeons agree that the ideal breast reduction should create a long lasting beautiful breast with minimal scar. Nowadays, surgeons are able to produce those ideal results with vertical mammaplasty In this article we are going to discuss our ten years experience with vertical mammaplasty. This paper is based on Lassus, Bozola and Lejour works, the final result with this techniques, has many advantages like that .the skin design is adaptable for any kind of breast, it’s a superior pedicle technique, where the larger breast the wider the pedicle is, the mammary gland is shaped independently of it’s skin envelop and produce long lasting projection breast with minimal scar. Some controversial points are avoided like suction lipectomy, because of the possibly calcifications that could hide some oncologic process, Finally we can say that the learning curve is easy with this technique (AU)


Subject(s)
Humans , Female , Adult , Middle Aged , Mammaplasty/history , Mammaplasty/methods , Mammaplasty , Hospitals, General/history , Hospitals, General , Breast Diseases/epidemiology , Mexico/epidemiology , Breast/physiopathology , Breast/surgery , Surgical Flaps
13.
J Virol ; 74(22): 10563-70, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11044100

ABSTRACT

Identifying protease cleavage sites contributes to our understanding of their specificity and biochemical properties and can help in designing specific inhibitors. One route to this end is the generation and screening of random libraries of cleavage sites. Both synthetic and phage-displayed libraries have been extensively used in vitro. We describe a novel system based on recombinant Sindbis virus which can be used to identify cleavage sites in vivo, thus eliminating the need for a purified enzyme and overcoming the problem of choosing the correct in vitro conditions. As a model we used the serine protease of the hepatitis C virus (HCV). We engineered the gene coding for this enzyme and two specific cleavage sites in the Sindbis virus structural gene and constructed libraries of viral genomes with a random sequence at either of the cleavage sites. The system was designed so that only viral genomes coding for sequences cleaved by the protease would produce viable viruses. With this system we selected viruses containing sequences mirroring those of the natural HCV protease substrates which were cleaved with comparable efficiencies.


Subject(s)
Hepacivirus/genetics , Peptide Library , Serine Endopeptidases/metabolism , Sindbis Virus/genetics , Antibodies/immunology , Hepacivirus/enzymology , Immunoblotting , Protein Biosynthesis , RNA, Viral , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sequence Analysis, DNA , Serine Endopeptidases/chemistry , Serine Endopeptidases/genetics , Sindbis Virus/metabolism , Substrate Specificity
14.
J Virol ; 74(13): 5933-8, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10846074

ABSTRACT

Hepatitis C virus (HCV) glycoprotein E2 binds to human cells by interacting with the CD81 molecule, which has been proposed to be the viral receptor. A correlation between binding to CD81 and species permissiveness to HCV infection has also been reported. We have determined the sequence of CD81 from the tamarin, a primate species known to be refractory to HCV infection. Tamarin CD81 (t-CD81) differs from the human molecule at 5 amino acid positions (155, 163, 169, 180, and 196) within the large extracellular loop (LEL), where the binding site for E2 has been located. Soluble recombinant forms of human CD81 (h-CD81), t-CD81, and African green monkey CD81 (agm-CD81) LEL molecules were analyzed by enzyme-linked immunosorbent assay for binding to E2 glycoprotein. Both h-CD81 and t-CD81 molecules were able to bind E2. Competition experiments showed that the two receptors cross-compete and that the t-CD81 binds with stronger affinity than the human molecule. Recently, h-CD81 residue 186 has been characterized as the critical residue involved in the interaction with E2. Recombinant CD81 mutant proteins were expressed to test whether human and tamarin receptors interacted with E2 in a comparable manner. Mutation of residue 186 (F186L) dramatically reduced the binding capability of t-CD81, a result that has already been demonstrated for the human receptor, whereas the opposite mutation (L186F) in agm-CD81 resulted in a neat gain of binding activity. Finally, the in vitro data were confirmed by detection of E2 binding to cotton-top tamarin (Saguinus oedipus) cell line B95-8 expressing endogenous CD81. These results indicate that the binding of E2 to CD81 is not predictive of an infection-producing interaction between HCV and host cells.


Subject(s)
Antigens, CD/metabolism , Glycoproteins/metabolism , Hepacivirus/physiology , Membrane Proteins/metabolism , Receptors, Virus/metabolism , Viral Envelope Proteins/metabolism , Amino Acid Sequence , Animals , Antigens, CD/genetics , Base Sequence , Binding Sites , Cell Line , Cloning, Molecular , DNA, Viral , Glycoproteins/genetics , Hepacivirus/genetics , Hepacivirus/metabolism , Humans , Membrane Proteins/genetics , Molecular Sequence Data , Receptors, Virus/genetics , Saguinus , Sequence Homology, Amino Acid , Solubility , Tetraspanin 28 , Tumor Cells, Cultured , Viral Envelope Proteins/genetics
15.
J Gen Virol ; 81(Pt 3): 759-67, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10675414

ABSTRACT

The RNA-dependent RNA polymerase activity of hepatitis C virus is carried out by the NS5B protein. The full-length protein was previously purified as a non-fusion protein from insect cells infected with a recombinant baculovirus. The characterization is now described of a C-terminal hydrophobic domain deletion mutant of NS5B purified from E. coli. In addition to increased solubility, deletion of this sequence also positively affected the polymerase enzymatic activity. The efficiency of nucleotide polymerization of both the full-length and the C-terminal truncated enzymes were compared on homopolymeric template-primer couples as well as on RNA templates with heteropolymeric sequences. The largest difference in the polymerase activity was observed on the latter. On all the templates, the increased activity could be ascribed, at least in part, to enhanced template turnover of the deletion mutant with respect to the full-length enzyme. The elongation rates of the two enzyme forms were compared under single processive cycle conditions. Under these conditions, both the full-length and the deletion mutant were able to incorporate about 700 nt/min.


Subject(s)
Hepacivirus/enzymology , Hepacivirus/genetics , RNA-Dependent RNA Polymerase/genetics , Animals , Enzyme Stability , Escherichia coli/genetics , Gene Expression , Genes, Viral , Kinetics , RNA-Dependent RNA Polymerase/chemistry , RNA-Dependent RNA Polymerase/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Deletion , Substrate Specificity
16.
Anal Biochem ; 266(2): 192-7, 1999 Jan 15.
Article in English | MEDLINE | ID: mdl-9888975

ABSTRACT

A novel radiometric in vitro assay for discovery of inhibitors of hepatitis C viral protease activity, suitable for high-throughput screening, was developed. The NS3 protein of hepatitis C virus (HCV) contains a serine protease, whose function is to process the majority of the nonstructural proteins of the viral polyprotein. The viral NS4A protein is a cofactor of NS3 protease activity in the cleavage of NS3-NS4A, NS4A-NS4B, NS4B-NS5A, and NS5A-NS5B junctions. To establish an in vitro assay system we used NS3 proteases from different HCV strains, purified from Escherichia coli and a synthetic radiolabeled peptide substrate that mimics the NS4A-NS4B junction. Upon incubation with the enzyme the substrate was separated from the radiolabeled cleavage product by addition of an ion exchange resin. The assay was performed in a microtiter plate format and offered the potential for assaying numerous samples using a laboratory robot. Taking advantage of these features, we used the assay to optimize reaction conditions by simultaneously varying different buffer components. We showed that physicochemical conditions affect NS3 protease activity in a strain-specific way. Furthermore, the sensitivity of the assay makes it suitable for detection and detailed mechanistic characterization of inhibitors with low-nanomolar affinities for the HCV serine protease.


Subject(s)
Radiometry/methods , Viral Nonstructural Proteins/analysis , Buffers , Endopeptidases/metabolism , Kinetics , Peptides/pharmacology , Protease Inhibitors/pharmacology , Sensitivity and Specificity , Time Factors , Viral Nonstructural Proteins/antagonists & inhibitors
17.
Circulation ; 98(22): 2370-6, 1998 Dec 01.
Article in English | MEDLINE | ID: mdl-9832480

ABSTRACT

BACKGROUND: Systemic markers of inflammation have been found in unstable angina. Disruption of culprit coronary stenoses may cause a greater inflammatory response in patients with unstable than those with stable angina. We assessed the time course of C-reactive protein (CRP), serum amyloid A protein (SAA), and interleukin-6 (IL-6) after single-vessel PTCA in 30 patients with stable and 56 patients with unstable angina (protocol A). We also studied 12 patients with stable and 15 with unstable angina after diagnostic coronary angiography (protocol B). METHODS AND RESULTS: Peripheral blood samples were taken before and 6, 24, 48, and 72 hours after PTCA or angiography. In protocol A, baseline CRP, SAA, and IL-6 levels were normal in 87% of stable and 29% of unstable patients. After PTCA, CRP, SAA, and IL-6 did not change in stable patients and unstable patients with normal baseline levels but increased in unstable patients with raised baseline levels (all P<0.001). In protocol B, CRP, SAA, and IL-6 did not change in stable angina patients after angiography but increased in unstable angina patients (all P<0.05). Baseline CRP and SAA levels correlated with their peak values after PTCA and angiography (all P<0.001). CONCLUSIONS: Our data suggest that plaque rupture per se is not the main cause of the acute-phase protein increase in unstable angina and that increased baseline levels of acute-phase proteins are a marker of the hyperresponsiveness of the inflammatory system even to small stimuli. Thus, an enhanced inflammatory response to nonspecific stimuli may be involved in the pathogenesis of unstable angina.


Subject(s)
Acute-Phase Reaction/etiology , Angina, Unstable/blood , Angina, Unstable/therapy , Angioplasty, Balloon, Coronary/adverse effects , Acute-Phase Proteins/analysis , Aged , Angina Pectoris/blood , C-Reactive Protein/analysis , Coronary Angiography/adverse effects , Female , Humans , Interleukin-6/blood , Male , Middle Aged , Prospective Studies , Serum Amyloid A Protein/analysis
18.
Circulation ; 94(5): 874-7, 1996 Sep 01.
Article in English | MEDLINE | ID: mdl-8790019

ABSTRACT

BACKGROUND: Elevated plasma levels of C-reactive protein have been found in the majority of patients with unstable angina. The evidence of elevated levels of acute-phase proteins in unstable angina is in line with a growing body of evidence that suggests that inflammation plays a role in this syndrome and is an indirect sign of increased production of interleukin-6, which is the major determinant of acute-phase-protein production by the liver. However, in unstable angina, there is no direct proof of the role played by interleukin-6. METHODS AND RESULTS: We measured levels of interleukin-6 in 38 patients with unstable angina at the time of their admission to the coronary care unit and in 29 patients with stable angina. In the same groups of patients, we also measured C-reactive protein. Interleukin-6 (undetectable, ie, < 3 pg/mL, in healthy volunteers) was detectable in 23 (61%) of 38 patients with unstable angina but in only 6 (21%) of 29 with stable angina (P < .01). Median interleukin-6 levels were 5.25 pg/mL (range, 0 to 90 pg/mL) in patients with unstable angina but were below the detection limit of the assay in patients with stable angina (range, 0 to 7 pg/mL). A significant correlation was observed between interleukin-6 and C-reactive protein levels (r = .4, P = .013). CONCLUSIONS: Our study demonstrates that raised levels of interleukin-6 are common in unstable angina, correlate with C-reactive protein, and are associated with prognosis, thus confirming the importance of the cytokine pathway for the production by the liver of acute-phase proteins and strengthening the importance of inflammation in this syndrome. Further studies are required to elucidate better the role of interleukins in unstable angina.


Subject(s)
Angina, Unstable/blood , Interleukin-6/blood , Aged , C-Reactive Protein/analysis , Female , Humans , Male , Middle Aged
19.
Pept Res ; 7(1): 27-31, 1994.
Article in English | MEDLINE | ID: mdl-8019059

ABSTRACT

We describe here a novel type of synthetic peptide library, named Multimeric Synthetic Peptide Combinatorial Library (M-SPCL), where multiple small peptide ligands are tied together in the same molecule. The advantage of using small peptides in the form of M-SPCL is two-fold: first, the high density assembly of the sequences on the branching scaffold leads to signal amplification, thereby effectively lowering the binding threshold for the selection of ligands; second, to interfere with protein-protein interactions, multimericity has been shown to be a desirable feature per se. The M-SPCL is prepared by solid-phase peptide synthesis, based on the structure of Multiple Antigen Peptides. When prepared in Positional Scanning format [C. Pinilla, J. Appel, P. Blanc and R.A. Houghten. 1992. BioTechniques 13: 901-905], selection is based on the amplified interaction of a single residue in a sequence-defined position. The usefulness of the new library was demonstrated by the selection of octameric peptides, which inhibit the binding of the cytokine human interleukin-6 to its receptor, with an apparent nanomolar affinity. Tetrameric, but not dimeric, branched peptides with the same sequences were also active with comparable affinity. The success of this approach is noteworthy, since screening of the corresponding monomeric pentapeptide SPCL did not lead to the selection of any inhibitory compound in the same system.


Subject(s)
Peptides/chemical synthesis , Peptides/pharmacology , Amino Acid Sequence , Interleukin-6/metabolism , Molecular Sequence Data , Receptors, Interleukin/metabolism , Receptors, Interleukin-6 , Sensitivity and Specificity
20.
Nucleic Acids Res ; 21(2): 289-94, 1993 Jan 25.
Article in English | MEDLINE | ID: mdl-7680115

ABSTRACT

The promoter regions of three IL-6 inducible genes, hemopexin (Hpx), haptoglobin (Hp) and C-reactive protein (CRP) contain cis-acting IL-6 responsive elements (IL-6REs) which are necessary and sufficient to induce IL-6 transcription activation. Transcription factors of the C/EBP family interact with IL-6REs. Among these, IL-6DBP/NF-IL6 plays a key role in IL-6 signal transduction because its trans-activation potential is induced by IL-6 in the human hepatoma cell line Hep3B. We show here that a different C/EBP-related factor, C/EBP delta/NF-IL6 beta, is the major IL-6 induced protein interacting with IL-6REs in the nuclei of Hep3B cells. In contrast to IL-6DBP/NF-IL6, whose activity in Hep3B cells is modulated by IL-6 via a post-translational mechanism, C/EBP delta/NF-IL6 beta is transcriptionally induced by IL-6. Another contrasting feature is that the C/EBP delta cDNA transfected in Hep3B cells activates transcription from an IL-6RE synthetic promoter in a constitutive manner which is not further enhanced by IL-6. Therefore, in Hep3B cells, two distinct members of the C/EBP family are recruited in the IL-6 signal transduction pathway via different mechanisms.


Subject(s)
Acute-Phase Proteins/genetics , DNA-Binding Proteins/genetics , Interleukin-6/physiology , Nuclear Proteins/genetics , Transcription Factors , Transcription, Genetic , Base Sequence , Blotting, Northern , Blotting, Western , CCAAT-Enhancer-Binding Protein-delta , CCAAT-Enhancer-Binding Proteins , Carcinoma, Hepatocellular , DNA/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Fluorescent Antibody Technique , Gene Expression Regulation , Humans , Molecular Sequence Data , Multigene Family , Nuclear Proteins/chemistry , Nuclear Proteins/metabolism , RNA, Messenger/metabolism , Regulatory Sequences, Nucleic Acid , Tumor Cells, Cultured
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