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1.
Pediatr Transplant ; 28(4): e14782, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38767001

RÉSUMÉ

BACKGROUND: Nutritional status in pediatric patients undergoing heart transplantation (HT) is frequently a focus of clinical management and requires high resource utilization. Pre-operative nutrition status has been shown to affect post-operative mortality but no studies have been performed to assess how nutritional status may change and the risk of developing nutritional comorbidities long-term in the post-transplant period. METHODS: A single-center retrospective chart review of patients ≥2 years of age who underwent heart transplantation between 1/1/2005 and 4/30/2020 was performed. Patient data were collected at listing, time of transplant, 1-year, and 3-year follow-up post-transplant. Nutrition status was classified based on body mass index (BMI) percentile in the primary analysis. Alternative nutritional indices, namely the nutrition risk index (NRI), prognostic nutrition index (PNI), and BMI z-score, were utilized in secondary analyses. RESULTS: Of the 63 patients included, the proportion of patients with overweight/obese status increased from 21% at listing to 41% at 3-year follow-up. No underweight patients at listing became overweight/obese at follow-up. Of patients who were overweight/obese at listing, 88% maintained that status at 3-year follow-up. Overweight/obese status at listing, 1-year, and 3-year post-transplantation were significantly associated with developing metabolic syndrome. In comparison to the alternative nutritional indices, BMI percentile best predicted post-transplant metabolic syndrome. CONCLUSIONS: The results suggest that pediatric patients who undergo heart transplantation are at risk of developing overweight/obesity and related nutritional sequelae (ie, metabolic syndrome). Improved surveillance and interventions targeted toward overweight/obese HT patients should be investigated to reduce the burden of associated comorbidities.


Sujet(s)
Transplantation cardiaque , Syndrome métabolique X , État nutritionnel , Complications postopératoires , Humains , Études rétrospectives , Mâle , Femelle , Syndrome métabolique X/étiologie , Syndrome métabolique X/épidémiologie , Enfant , Adolescent , Enfant d'âge préscolaire , Complications postopératoires/étiologie , Complications postopératoires/épidémiologie , Indice de masse corporelle , Obésité pédiatrique/complications , Études de suivi , Facteurs de risque
2.
Cryo Letters ; 44(4): 197-207, 2023.
Article de Anglais | MEDLINE | ID: mdl-37883137

RÉSUMÉ

BACKGROUND: The atypical seed storage behaviour reported in several orchid species justifies cryopreservation as a complementary conservation strategy to conventional seed banking. OBJECTIVE: This study aimed to assess the seed cryopreservation potential of five orchid species; two tropical epiphytic, Indonesian species (Dendrobium strebloceras, D. lineale), one temperate epiphytic, New Zealand species (D. cunninghamii) and two temperate terrestrial, New Zealand species (Pterostylis banksii, Thelymitra nervosa). MATERIALS AND METHODS: Seeds were cryopreserved by direct immersion in liquid nitrogen (LN) and through the application of a cryoprotectant vitrification method. For the latter, seeds were exposed to Plant Vitrification Solution 2 (PVS2) for 0, 20, 50, and 70 min, at either room temperature or on ice, prior to immersion in LN. RESULTS: Seeds of all the studied species germinated well following direct cooling in LN. There was no difference in the seedling development capability between cryopreserved and non-cryopreserved seeds of both tropical epiphytic species and direct immersion in LN enhanced seed germination and shoot formation in both temperate terrestrials. CONCLUSION: Through a range of analyses of germination and post-germination growth, our study shows the potential for cryopreserving epiphytic or terrestrial orchids from tropical and temperate regions. Doi: 10.54680/fr23410110312.


Sujet(s)
Cryoconservation , Orchidaceae , Cryoconservation/méthodes , Indonésie , Nouvelle-Zélande , Germination , Graines
4.
Plant Biol (Stuttg) ; 24(1): 168-175, 2022 Jan.
Article de Anglais | MEDLINE | ID: mdl-34724312

RÉSUMÉ

Changes in seed lipid composition during ageing are associated with seed viability loss in many plant species. However, due to their small seed size, this has not been previously explored in orchids. We characterized and compared the seed viability and fatty acid profiles of five orchid species before and after ageing: one tropical epiphytic orchid from Indonesia (Dendrobium strebloceras), and four temperate species from New Zealand, D. cunninghamii (epiphytic), and Gastrodia cunninghamii, Pterostylis banksii and Thelymitra nervosa (terrestrial). Seeds were aged under controlled laboratory conditions (3-month storage at 60% RH and 20 °C). Seed viability was tested before and after ageing using tetrazolium chloride staining. Fatty acid methyl esters from fresh and aged seeds were extracted through trans-esterification, and then analysed using gas chromatography-mass spectrometry. All species had high initial viability (>80%) and experienced significant viability loss after ageing. The saturated, polyunsaturated, monounsaturated and total fatty acid content decreased with ageing in all species, but this reduction was only significant for D. strebloceras, D. cunninghamii and G. cunninghamii. Our results suggest that fatty acid degradation is a typical response to ageing in orchids, albeit with species variation in magnitude, but the link between fatty acid degradation and viability was not elucidated. Pterostylis banksii exemplified this variation; it showed marked viability loss despite not having a significant reduction in its fatty acid content after ageing. More research is required to identify the effect of ageing on fatty acid composition in orchids, and its contribution to seed viability loss.


Sujet(s)
Acides gras , Orchidaceae , Chromatographie gazeuse-spectrométrie de masse , Graines
5.
J Neuromuscul Dis ; 8(1): 53-61, 2021.
Article de Anglais | MEDLINE | ID: mdl-32925088

RÉSUMÉ

We report the recruitment activities and outcomes of a multi-disease neuromuscular patient registry in Canada. The Canadian Neuromuscular Disease Registry (CNDR) registers individuals across Canada with a confirmed diagnosis of a neuromuscular disease. Diagnosis and contact information are collected across all diseases and detailed prospective data is collected for 5 specific diseases: Amyotrophic Lateral Sclerosis (ALS), Duchenne Muscular Dystrophy (DMD), Myotonic Dystrophy (DM), Limb Girdle Muscular Dystrophy (LGMD), and Spinal Muscular Atrophy (SMA). Since 2010, the CNDR has registered 4306 patients (1154 pediatric and 3148 adult) with 91 different neuromuscular diagnoses and has facilitated 125 projects (73 academic, 3 not-for-profit, 3 government, and 46 commercial) using registry data. In conclusion, the CNDR is an effective and productive pan-neuromuscular registry that has successfully facilitated a substantial number of studies over the past 10 years.


Sujet(s)
Sclérose latérale amyotrophique , Amyotrophie spinale , Dystrophies musculaires des ceintures , Myopathie de Duchenne , Dystrophie myotonique , Enregistrements , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Canada , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Adulte d'âge moyen , Jeune adulte
6.
Viruses ; 12(11)2020 10 28.
Article de Anglais | MEDLINE | ID: mdl-33126536

RÉSUMÉ

Cytomegaloviruses all encode the viral inhibitor of caspase-8-induced apoptosis (vICA). After binding to this initiator caspase, vICA blocks caspase-8 proteolytic activity and ability to activate caspase-3 and/or caspase-7. In this manner, vICA has long been known to prevent apoptosis triggered via tumor necrosis factor (TNF) family death receptor-dependent extrinsic signaling. Here, we employ fully wild-type murine cytomegalovirus (MCMV) and vICA-deficient MCMV (∆M36) to investigate the contribution of TNF signaling to apoptosis during infection of different cell types. ∆M36 shows the expected ability to kill mouse splenic hematopoietic cells, bone marrow-derived macrophages (BMDM), and dendritic cells (BMDC). Antibody blockade or genetic elimination of TNF protects myeloid cells from death, and caspase-8 activation accompanies cell death. Interferons, necroptosis, and pyroptotic gasdermin D (GSDMD) do not contribute to myeloid cell death. Human and murine fibroblasts or murine endothelial cells (SVEC4-10) normally insensitive to TNF become sensitized to ∆M36-induced apoptosis when treated with TNF or TNF-containing BMDM-conditioned medium. We demonstrate that myeloid cells are the natural source of TNF that triggers apoptosis in either myeloid (autocrine) or non-myeloid cells (paracrine) during ∆M36 infection of mice. Caspase-8 suppression by vICA emerges as key to subverting innate immune elimination of a wide variety of infected cell types.


Sujet(s)
Apoptose/génétique , Caspase 8/métabolisme , Muromegalovirus/pathogénicité , Transduction du signal , Facteur de nécrose tumorale alpha/immunologie , Protéines virales/génétique , Animaux , Caspase 8/génétique , Survie cellulaire , Cellules dendritiques/immunologie , Cellules dendritiques/virologie , Cellules endothéliales/immunologie , Cellules endothéliales/virologie , Humains , Protéines et peptides de signalisation intracellulaire/métabolisme , Macrophages/immunologie , Macrophages/virologie , Souris , Souris knockout , Muromegalovirus/immunologie , Cellules myéloïdes/immunologie , Cellules myéloïdes/virologie , Cellules NIH 3T3 , Facteur de nécrose tumorale alpha/génétique
7.
Oncogene ; 38(31): 5971-5986, 2019 08.
Article de Anglais | MEDLINE | ID: mdl-31253870

RÉSUMÉ

Early Growth Response 1 (EGR1) is a stress response transcription factor with multiple tumour suppressor roles in breast tissue, whose expression is often lost in breast cancers. We have previously shown that the breast cancer oncogene TBX2 (T-BOX2) interacts with EGR1 to co-repress EGR1-target genes including the breast tumour suppressor NDRG1. Here, we show the mechanistic basis of this TBX2 repression complex. We show that siRNA knockdown of TBX2, EGR1, Heterochromatin Protein 1 (HP1) isoforms and the generic HP1-associated corepressor protein KAP1 all resulted in growth inhibition of TBX2-expressing breast cancer cells. We show that TBX2 interacts with HP1 through a conserved HP1-binding motif in its N-terminus, which in turn leads to the recruitment of KAP1 and other associated proteins. Mutation of the TBX2 HP1 binding domain abrogates the TBX2-HP1 interaction and loss of repression of target genes such as NDRG1. Chromatin-immunoprecipitation (ChIP) assays showed that TBX2 establishes a repressive chromatin mark, specifically H3K9me3, around the NDRG1 proximal promoter coincident with the recruitment of the DNA methyltransferase DNMT3B and histone methyltransferase (HMT) complex components (G9A, Enhancer of Zeste 2 (EZH2) and Suppressor of Zeste 12 (SUZ12)). Knockdown of G9A, EZH2 or SUZ12 resulted in upregulation of TBX2/EGR1 co-regulated targets accompanied by a dramatic inhibition of cell proliferation. We show that a generic inhibitor of HMT activity, DzNep, phenocopies expression of an inducible dominant negative TBX2. Knockdown of TBX2, KAP1 or HP1 inhibited NDRG1 promoter decoration specifically with the H3K9me3 repression mark. Correspondingly, treatment with a G9A inhibitor effectively reversed TBX2 repression of NDRG1 and synergistically downregulated cell proliferation following TBX2 functional inhibition. These data demonstrate that TBX2 promotes suppression of normal growth control mechanisms through recruitment of a large repression complex to EGR1-responsive promoters leading to the uncontrolled proliferation of breast cancer cells.


Sujet(s)
Tumeurs du sein/anatomopathologie , Prolifération cellulaire/génétique , Protéines chromosomiques nonhistones/métabolisme , Facteur de transcription EGR-1/métabolisme , Régions promotrices (génétique) , Protéines à domaine boîte-T/métabolisme , Tumeurs du sein/génétique , Tumeurs du sein/métabolisme , Protéines du cycle cellulaire/génétique , Lignée cellulaire tumorale , Chromatine/génétique , Immunoprécipitation de la chromatine , Homologue-5 de la protéine chromobox , Protéines chromosomiques nonhistones/génétique , Facteur de transcription EGR-1/génétique , Femelle , Techniques de knock-down de gènes , Histone méthyltransférases/métabolisme , Humains , Protéines et peptides de signalisation intracellulaire/génétique , Liaison aux protéines , Protéines de répression/génétique , Protéines à domaine boîte-T/génétique , Protéine-28 à motif tripartite/génétique
9.
Epidemiol Infect ; 147: e122, 2019 01.
Article de Anglais | MEDLINE | ID: mdl-30869008

RÉSUMÉ

UNAIDS established fast-track targets of 73% and 86% viral suppression among human immunodeficiency virus (HIV)-positive individuals by 2020 and 2030, respectively. The epidemiologic impact of achieving these goals is unknown. The HIV-Calibrated Dynamic Model, a calibrated agent-based model of HIV transmission, is used to examine scenarios of incremental improvements to the testing and antiretroviral therapy (ART) continuum in South Africa in 2015. The speed of intervention availability is explored, comparing policies for their predicted effects on incidence, prevalence and achievement of fast-track targets in 2020 and 2030. Moderate (30%) improvements in the continuum will not achieve 2020 or 2030 targets and have modest impacts on incidence and prevalence. Improving the continuum by 80% and increasing availability reduces incidence from 2.54 to 0.80 per 100 person-years (-1.73, interquartile range (IQR): -1.42, -2.13) and prevalence from 26.0 to 24.6% (-1.4 percentage points, IQR: -0.88, -1.92) from 2015 to 2030 and achieves fast track targets in 2020 and 2030. Achieving 90-90-90 in South Africa is possible with large improvements to the testing and treatment continuum. The epidemiologic impact of these improvements depends on the balance between survival and transmission benefits of ART with the potential for incidence to remain high.


Sujet(s)
Agents antiVIH/usage thérapeutique , Surveillance épidémiologique , Infections à VIH/épidémiologie , Infections à VIH/prévention et contrôle , Adolescent , Adulte , Thérapie antirétrovirale hautement active , Femelle , Infections à VIH/traitement médicamenteux , Humains , Mâle , République d'Afrique du Sud/épidémiologie , Charge virale , Jeune adulte
10.
R Soc Open Sci ; 5(6): 171628, 2018 Jun.
Article de Anglais | MEDLINE | ID: mdl-30110439

RÉSUMÉ

Soft slender structures are ubiquitous in natural and artificial systems, in active and passive settings and across scales, from polymers and flagella, to snakes and space tethers. In this paper, we demonstrate the use of a simple and practical numerical implementation based on the Cosserat rod model to simulate the dynamics of filaments that can bend, twist, stretch and shear while interacting with complex environments via muscular activity, surface contact, friction and hydrodynamics. We validate our simulations by solving a number of forward problems involving the mechanics of passive filaments and comparing them with known analytical results, and extend them to study instabilities in stretched and twisted filaments that form solenoidal and plectonemic structures. We then study active filaments such as snakes and other slender organisms by solving inverse problems to identify optimal gaits for limbless locomotion on solid surfaces and in bulk liquids.

11.
Physiol Behav ; 180: 98-102, 2017 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-28821447

RÉSUMÉ

INTRODUCTION: Currently there are no data examining the impact of exercise on the perception of time, which is surprising as optimal competitive performance is dependent on accurate pacing using knowledge of time elapsed. METHODS: With institutional ethics approval, 12 recreationally active adult participants (f=7, m=5) undertook both 30s Wingate cycles and 20min (1200s) rowing ergometer bouts as short and long duration self-paced exercise trials, in each of three conditions on separate occasions: 1) light exertion: RPE 11, 2) heavy exertion: RPE 15, 3) maximal exertion: RPE 20. Participants were unaware of exercise duration and were required to verbally indicate when they perceived (subjective time) 1) 25%, 2) 50%, 3) 75% and 4) 100% of each bout's measured (chronological) time had elapsed. RESULTS: In response to the Wingate task, there was no difference between durations of subjective time at the 25%, nor at the 50% interval. However, at the 75% and 100% intervals, the estimate for the RPE 20 condition was shortest (P<0.01). In response to rowing, there were no differences at the 25% interval, but there was some evidence that the RPE 20 condition was perceived shorter at 50%. At 75% and 100%, the RPE 20 condition was perceived to be shorter than both RPE 15 (P=0.04) and RPE 11 (P=0.008) conditions. CONCLUSION: This study is the first to empirically demonstrate that exercise intensity distorts time perception, particularly during maximal exercise. Consequently external feedback of chronological time may be an important factor for athletes undertaking maximal effort tasks or competitions.


Sujet(s)
Exercice physique , Endurance physique/physiologie , Effort physique/physiologie , Perception du temps/physiologie , Adolescent , Adulte , Analyse de variance , Épreuve d'effort , Femelle , Humains , Mâle , Consommation d'oxygène , Facteurs temps , Jeune adulte
12.
Expert Rev Gastroenterol Hepatol ; 11(6): 593-601, 2017 Jun.
Article de Anglais | MEDLINE | ID: mdl-28276815

RÉSUMÉ

BACKGROUND: We investigated the real-world effectiveness of interferon-free regimens for the treatment of patients with compensated cirrhosis infected with hepatitis C virus (HCV). METHOD: Using the Irish national HCV treatment registry, the effectiveness and safety of interferon-free regimens for HCV-infected patients treated between April 2015 and August 2016, was determined. RESULTS: A SVR12 was achieved in 86% of subjects treated with sofosbuvir/ledipasvir ± ribavirin (SOF/LDV±RBV), 93% treated with paritaprevir, ombitasvir and ritonavir combined with dasabuvir ± ribavirin (3D±RBV) and 89% treated with sofosbuvir/daclatasvir ± ribavirin (SOF/DCV±RBV). The discontinuation rate was 5% and the on-treatment mortality rate was 1%. CONCLUSION: The availability of interferon-free regimens represents a significant breakthrough for the treatment of HCV infection. Treatments options, with high SVR12 rates, are now available for patients with compensated cirrhosis who were unsuitable for treatment with interferon-based regimens. Data obtained from studies conducted in real world practice provide robust information fundamental for input into future economic evaluations for agents used for the treatment of HCV infection.


Sujet(s)
Antiviraux/usage thérapeutique , Benzimidazoles/usage thérapeutique , Fluorènes/usage thérapeutique , Accessibilité des services de santé , Hepacivirus/effets des médicaments et des substances chimiques , Hépatite C/traitement médicamenteux , Cirrhose du foie/traitement médicamenteux , Ribavirine/usage thérapeutique , Uridine monophosphate/analogues et dérivés , Adulte , Antiviraux/effets indésirables , Benzimidazoles/effets indésirables , Association de médicaments , Femelle , Fluorènes/effets indésirables , Génotype , Hepacivirus/génétique , Hepacivirus/croissance et développement , Hépatite C/complications , Hépatite C/diagnostic , Hépatite C/mortalité , Humains , Irlande , Cirrhose du foie/diagnostic , Cirrhose du foie/mortalité , Cirrhose du foie/virologie , Études longitudinales , Mâle , Adulte d'âge moyen , Évaluation de programme , Études prospectives , Enregistrements , Ribavirine/effets indésirables , Sofosbuvir , Réponse virologique soutenue , Facteurs temps , Résultat thérapeutique , Uridine monophosphate/effets indésirables , Uridine monophosphate/usage thérapeutique
13.
Proc Natl Acad Sci U S A ; 114(13): E2786-E2795, 2017 03 28.
Article de Anglais | MEDLINE | ID: mdl-28292903

RÉSUMÉ

The complex interplay between caspase-8 and receptor-interacting protein (RIP) kinase RIP 3 (RIPK3) driving extrinsic apoptosis and necroptosis is not fully understood. Murine cytomegalovirus triggers both apoptosis and necroptosis in infected cells; however, encoded inhibitors of caspase-8 activity (M36) and RIP3 signaling (M45) suppress these antiviral responses. Here, we report that this virus activates caspase-8 in macrophages to trigger apoptosis that gives rise to secondary necroptosis. Infection with double-mutant ΔM36/M45mutRHIM virus reveals a signaling pattern in which caspase-8 activates caspase-3 to drive apoptosis with subsequent RIP3-dependent activation of mixed lineage kinase domain-like (MLKL) leading to necroptosis. This combined cell death signaling is highly inflammatory, greater than either apoptosis induced by ΔM36 or necroptosis induced by M45mutRHIM virus. IL-6 production by macrophages is dramatically increased during double-mutant virus infection and correlates with faster antiviral responses in the host. Collaboratively, M36 and M45 target caspase-8 and RIP3 pathways together to suppress this proinflammatory cell death. This study reveals the effect of antiviral programmed cell death pathways on inflammation, shows that caspase-8 activation may go hand-in-hand with necroptosis in macrophages, and revises current understanding of independent and collaborative functions of M36 and M45 in blocking apoptotic and necroptotic cell death responses.


Sujet(s)
Apoptose , Infections à Herpesviridae/médecine vétérinaire , Muromegalovirus/métabolisme , Ribonucleotide reductases/métabolisme , Maladies des rongeurs/physiopathologie , Protéines virales/métabolisme , Animaux , Caspase 8/génétique , Caspase 8/immunologie , Infections à Herpesviridae/immunologie , Infections à Herpesviridae/physiopathologie , Infections à Herpesviridae/virologie , Interactions hôte-pathogène , Souris , Muromegalovirus/classification , Muromegalovirus/génétique , Receptor-Interacting Protein Serine-Threonine Kinases/génétique , Receptor-Interacting Protein Serine-Threonine Kinases/immunologie , Ribonucleotide reductases/génétique , Maladies des rongeurs/génétique , Maladies des rongeurs/immunologie , Maladies des rongeurs/virologie , Protéines virales/génétique
14.
J Microsc ; 263(3): 293-9, 2016 09.
Article de Anglais | MEDLINE | ID: mdl-26937849

RÉSUMÉ

We previously showed that long-lived nanoemulsions, seeming initially vesicular, might be prepared simply by diluting and cooling (quenching) warm microemulsions with n-hexadecane with precooled water. In this paper, we confirm that these systems are vesicular dispersions when fresh, and they can be made with similar structures and compositional dependence using alkanes with chain lengths ranging from octane to hexadecane. The nanostructures of fresh nanoemulsions are imaged with cryogenic transmission electron microscopy (cryo-TEM). We confirm that water-continuous microemulsions give simple dispersions of vesicles (sometimes unilamellar), typically less than 100 nm in diameter; these systems can avoid separation for over 2 months. Selected samples were also prepared using halogenated alkanes to create additional contrast in the cryo-TEM, allowing us to confirm that the oil is located in the observed vesicular structures.

15.
Int J STD AIDS ; 26(8): 593-4, 2015 Jul.
Article de Anglais | MEDLINE | ID: mdl-25147237

RÉSUMÉ

A review of a large number of HIV-1 tropism test requests (n = 1148) performed at a London tertiary referral centre was carried out. The aim was to establish whether these were being performed in line with recommendations from published guidelines and whether this represented the most cost-effective use of these tests in informing prescribing decisions of the CCR5 antagonist drug, maraviroc. The cost of these assays within the UK was covered by commercial funding until April 2013 which has subsequently been withdrawn. Furthermore, all healthcare settings are under increasing cost constraints and hence establishing the real utility and appropriate use of these tests is of vital importance.


Sujet(s)
Antagonistes des récepteurs CCR5/usage thérapeutique , Cyclohexanes/usage thérapeutique , Infections à VIH/diagnostic , ARN viral/génétique , Triazoles/usage thérapeutique , Tropisme viral/effets des médicaments et des substances chimiques , Cyclohexanes/économie , ADN viral/composition chimique , ADN viral/génétique , Ordonnances médicamenteuses/économie , Femelle , Génotype , Infections à VIH/traitement médicamenteux , Infections à VIH/virologie , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/effets des médicaments et des substances chimiques , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , Humains , Londres , Mâle , Maraviroc , Audit médical , Types de pratiques des médecins , Études rétrospectives , Analyse de séquence d'ADN , Triazoles/économie , Tropisme viral/génétique
16.
Cell Mol Immunol ; 12(2): 170-9, 2015 Mar.
Article de Anglais | MEDLINE | ID: mdl-25544503

RÉSUMÉ

A universal cytomegalovirus (CMV) vaccination promises to reduce the burden of the developmental damage that afflicts up to 0.5% of live births worldwide. An effective vaccination that prevents transplacental transmission would reduce CMV congenital disease and CMV-associated still births and leave populations less susceptible to opportunistic CMV disease. Thus, a vaccination against this virus has long been recognized for the potential of enormous health-care savings because congenital damage is life-long and existing anti-viral options are limited. Vaccine researchers, industry leaders, and regulatory representatives have discussed the challenges posed by clinical efficacy trials that would lead to a universal CMV vaccine, reviewing the links between infection and disease, and identifying settings where disrupting viral transmission might provide a surrogate endpoint for disease prevention. Reducing the complexity of such trials would facilitate vaccine development. Children and adolescents are the targets for universal vaccination, with the expectation of protecting the offspring of immunized women. Given that a majority of females worldwide experience CMV infection during childhood, a universal vaccine must boost natural immunity and reduce transmission due to reactivation and re-infection as well as primary infection during pregnancy. Although current vaccine strategies recognize the value of humoral and cellular immunity, the precise mechanisms that act at the placental interface remain elusive. Immunity resulting from natural infection appears to limit rather than prevent reactivation of latent viruses and susceptibility to re-infection, leaving a challenge for universal vaccination to improve upon natural immunity levels. Despite these hurdles, early phase clinical trials have achieved primary end points in CMV seronegative subjects. Efficacy studies must be expanded to mixed populations of CMV-naive and naturally infected subjects to understand the overall efficacy and potential. Together with CMV vaccine candidates currently in clinical development, additional promising preclinical strategies continue to come forward; however, these face limitations due to the insufficient understanding of host defense mechanisms that prevent transmission, as well as the age-old challenges of reaching the appropriate threshold of immunogenicity, efficacy, durability and potency. This review focuses on the current understanding of natural and CMV vaccine-induced protective immunity.


Sujet(s)
Infections à cytomégalovirus/prévention et contrôle , Vaccins contre le cytomégalovirus/usage thérapeutique , Cytomegalovirus/immunologie , Infections à cytomégalovirus/immunologie , Infections à cytomégalovirus/virologie , Humains , Vaccination
17.
18.
Gynecol Oncol Case Rep ; 6: 31-3, 2013.
Article de Anglais | MEDLINE | ID: mdl-24371714

RÉSUMÉ

•Treatment of stage 1A1 cancer of the cervix often involves preservation of the corpus.•Rarely metastasis to the corpus can occur in these cases.

19.
J Clin Virol ; 58(2): 468-73, 2013 Oct.
Article de Anglais | MEDLINE | ID: mdl-23954217

RÉSUMÉ

BACKGROUND: Studies have shown that low-frequency resistance mutations can influence treatment outcome. However, the lack of a standardized high-throughput assay has precluded their detection in clinical settings. OBJECTIVE: To evaluate the performance of the Roche prototype 454 UDS HIV-1 drug resistance assay (UDS assay) in a routine diagnostic laboratory. STUDY DESIGN: 50 plasma samples, previously characterized by population sequencing and that had shown ≥1 resistance associated mutation (RAM), were retrospectively tested by the UDS assay, including 18 B and 32 non-B subtypes; viral loads between 114-1,806,407 cp/ml; drug-naive (n=27) and drug-experienced (n=23) individuals. RESULTS: The UDS assay was successful for 37/50 (74%) samples. It detected all RAMs found by population sequencing at frequencies above 20%. In addition, 39 low-frequency RAMs were exclusively detected by the UDS assay at frequencies below 20% in both drug-naïve (19/26, 73%) and drug-experienced (9/18, 50%) individuals. UDS results would lead to changes from susceptible to resistant to efavirenz (EFV) in one drug-naive individual with suboptimal response to an EFV-containing regimen and from susceptible to resistance to lamivudine (3TC) in one drug naïve subject who subsequently failed a 3TC-containing regimen and in a treatment experienced subject who had failed a 3TC-containing regimen. CONCLUSIONS: The UDS assay performed well across a wide range of subtypes and viral loads; it showed perfect agreement with population sequencing for all RAMs analyzed. In addition, the UDS assay detected additional mutations at frequencies below 20% which correlate with patients' treatment history and had in some cases important prognostic implications.


Sujet(s)
Résistance virale aux médicaments , Infections à VIH/virologie , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , Séquençage nucléotidique à haut débit/méthodes , Tests de sensibilité microbienne/méthodes , ARN viral/génétique , Génotype , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/effets des médicaments et des substances chimiques , Humains , Mutation , Plasma sanguin/virologie , Études rétrospectives
20.
J Virol ; 87(20): 11107-20, 2013 Oct.
Article de Anglais | MEDLINE | ID: mdl-23926341

RÉSUMÉ

Human cytomegalovirus (HCMV), a betaherpesvirus, can cause severe disease in immunosuppressed patients and following congenital infection. A vaccine that induces both humoral and cellular immunity may be required to prevent congenital infection. Dense bodies (DBs) are complex, noninfectious particles produced by HCMV-infected cells and may represent a vaccine option. As knowledge of the antigenicity and immunogenicity of DB is incomplete, we explored characterization methods and defined DB production methods, followed by systematic evaluation of neutralization and cell-mediated immune responses to the DB material in BALB/c mice. DBs purified from Towne-infected cultures treated with the viral terminase inhibitor 2-bromo-5,6-dichloro-1-beta-d-ribofuranosyl benzimidazole riboside (BDCRB) were characterized by nanoparticle tracking analysis (NTA), two-dimensional fluorescence difference gel electrophoresis (2D-DIGE), immunoblotting, quantitative enzyme-linked immunosorbent assay, and other methods. The humoral and cellular immune responses to DBs were compared to the immunogenicity of glycoprotein B (gB) administered with the adjuvant AddaVax (gB/AddaVax). DBs induced neutralizing antibodies that prevented viral infection of cultured fibroblasts and epithelial cells and robust cell-mediated immune responses to multiple viral proteins, including pp65, gB, and UL48. In contrast, gB/AddaVax failed to induce neutralizing antibodies that prevented infection of epithelial cells, highlighting a critical difference in the humoral responses induced by these vaccine candidates. Our data advance the potential for the DB vaccine approach, demonstrate important immunogenicity properties, and strongly support the further evaluation of DBs as a CMV vaccine candidate.


Sujet(s)
Anticorps neutralisants/sang , Anticorps antiviraux/sang , Vaccins contre le cytomégalovirus/immunologie , Cytomegalovirus/immunologie , Cellules épithéliales/virologie , Fibroblastes/virologie , Immunité cellulaire , Animaux , Anticorps neutralisants/immunologie , Anticorps antiviraux/immunologie , Vaccins contre le cytomégalovirus/administration et posologie , Vaccins contre le cytomégalovirus/isolement et purification , Cellules épithéliales/immunologie , Femelle , Fibroblastes/immunologie , Souris , Souris de lignée BALB C
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