Identification of molecular factors influencing Bovine alphaherpesvirus type 1 replication capacity and virulence

2021 ◽  
Author(s):  
◽  
Tristan Jacob Russell Wimpenny
Keyword(s):  
Replication Capacity ◽  
Factors Influencing

Factors influencing adherence among youth with Type-1-Diabetes Mellitus - the Hungarian case

2020 ◽  
Vol 16 ◽  
Author(s):  
Beáta Erika Nagy ◽  
Brigitta Munkácsi ◽  
Karolina Eszter Kovács
Keyword(s):  
Diabetes Mellitus ◽  
Type 1 Diabetes ◽  
Type 1 Diabetes Mellitus ◽  
Birth Order ◽  
Insulin Pump ◽  
Demographic Variables ◽  
Insulin Pump Therapy ◽  
Factors Influencing ◽  
Group Comparisons

Background & Introduction: Due to the increasing prevalence of type-1-diabetes an increasing number of studies draws investigation draws attention to its psychological effects and long-term consequences. As Type 1 Diabetes Mellitus is a chronic, non-curable, yet maintanable condition, with the affected children and their families facing a lifelong challenge. Our research focuses on the factors influencing adherence. Methods & Results: The adherence of youth was examined in a sample involving 114 patients treated in the Medical and Health Science Centre at the University of Debrecen by employing a new adherence questionnaire (DAQ abbreviated version, Munkácsi et al, 2019) (DAF 2017; N=114). The influence of socio-demographic variables and those related to the disease (age at the diagnosis, time elapsed since diagnosis, method of treatment, the time elapsed since the use of the pump) were measured by linear regression. Furthermore, the between-group comparisons were made by independent sample t-tests and variance analysis. The investigation was carried out between September 2017 and May 2018. The effect of using insulin pump as therapy is significant and positive (0.36. p=0.045). The adherence of the patients using insulin pump is higher while the effect of the age at the diagnosis has a significantly negative effect (-.247, p=0.035). Thus, earlier detection of the disease may lead to a higher level of adherence. The effects of the socio-demographic variables (gender, family structure, educational level, type of the settlement, owning sibling and birth order) were not significant (p>0.05). Regarding the between-group comparisons, a significant difference could be pointed out concerning the siblings and birth-order as the adherence of the those with siblings was higher (p=0.044). Moreover, concerning insulin pump therapy, the adherence of patients using pump was significantly better (p=0.048). Also, regarding the age of the diagnosis, the adherence of those diagnosed before 12 was seemingly higher (p=0.039). Concerning the other socio-demographical and disease-related variables, no significant differences could be detected. Conclusions: The results suggest that the treatment has an outstanding role in the adherence of the disease. Moreover, the role of the appropriate treatment, living conditions as well as the early diagnosis is relevant.

scholarly journals Novel Single-Cell-Level Phenotypic Assay for Residual Drug Susceptibility and Reduced Replication Capacity of Drug-Resistant Human Immunodeficiency Virus Type 1

2004 ◽  
Vol 78 (4) ◽  
pp. 1718-1729 ◽  
Author(s):  
Haili Zhang ◽  
Yan Zhou ◽  
Cecily Alcock ◽  
Tara Kiefer ◽  
Daphne Monie ◽  
...  
Keyword(s):  
Drug Combination ◽  
Wild Type Virus ◽  
Replication Capacity ◽  
Drug Resistant ◽  
Type Virus ◽  
Wild Type ◽  
Cell Level ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1)-infected individuals who develop drug-resistant virus during antiretroviral therapy may derive benefit from continued treatment for two reasons. First, drug-resistant viruses can retain partial susceptibility to the drug combination. Second, therapy selects for drug-resistant viruses that may have reduced replication capacities relative to archived, drug-sensitive viruses. We developed a novel single-cell-level phenotypic assay that allows these two effects to be distinguished and compared quantitatively. Patient-derived gag-pol sequences were cloned into an HIV-1 reporter virus that expresses an endoplasmic reticulum-retained Env-green fluorescent protein fusion. Flow cytometric analysis of single-round infections allowed a quantitative analysis of viral replication over a 4-log dynamic range. The assay faithfully reproduced known in vivo drug interactions occurring at the level of target cells. Simultaneous analysis of single-round infections by wild-type and resistant viruses in the presence and absence of the relevant drug combination divided the benefit of continued nonsuppressive treatment into two additive components, residual virus susceptibility to the drug combination and selection for drug-resistant variants with diminished replication capacities. In some patients with drug resistance, the dominant circulating viruses retained significant susceptibility to the combination. However, in other cases, the dominant drug-resistant viruses showed no residual susceptibility to the combination but had a reduced replication capacity relative to the wild-type virus. In this case, simplification of the regimen might still allow adequate suppression of the wild-type virus. In a third pattern, the resistant viruses had no residual susceptibility to the relevant drug regimen but nevertheless had a replication capacity equivalent to that of wild-type virus. In such cases, there is no benefit to continued treatment. Thus, the ability to simultaneously analyze residual susceptibility and reduced replication capacity of drug-resistant viruses may provide a basis for rational therapeutic decisions in the setting of treatment failure.

scholarly journals The Human Immunodeficiency Virus Type 1 Nonnucleoside Reverse Transcriptase Inhibitor Resistance Mutation I132M Confers Hypersensitivity to Nucleoside Analogs

2009 ◽  
Vol 83 (8) ◽  
pp. 3826-3833 ◽  
Author(s):  
Zandrea Ambrose ◽  
Brian D. Herman ◽  
Chih-Wei Sheen ◽  
Shannon Zelina ◽  
Katie L. Moore ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Reverse Transcriptase ◽  
Human Immunodeficiency Virus Type ◽  
Nucleoside Analogs ◽  
Replication Capacity ◽  
Immunodeficiency Virus ◽  
Viral Replication Capacity ◽  
Rt Inhibitors ◽  
Hiv 1

ABSTRACT We previously identified a rare mutation in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT), I132M, which confers high-level resistance to the nonnucleoside RT inhibitors (NNRTIs) nevirapine and delavirdine. In this study, we have further characterized the role of this mutation in viral replication capacity and in resistance to other RT inhibitors. Surprisingly, our data show that I132M confers marked hypersusceptibility to the nucleoside analogs lamivudine (3TC) and tenofovir at both the virus and enzyme levels. Subunit-selective mutagenesis studies revealed that the mutation in the p51 subunit of RT was responsible for the increased sensitivity to the drugs, and transient kinetic analyses showed that this hypersusceptibility was due to I132M decreasing the enzyme's affinity for the natural dCTP substrate but increasing its affinity for 3TC-triphosphate. Furthermore, the replication capacity of HIV-1 containing I132M is severely impaired. This decrease in viral replication capacity could be partially or completely compensated for by the A62V or L214I mutation, respectively. Taken together, these results help to explain the infrequent selection of I132M in patients for whom NNRTI regimens are failing and furthermore demonstrate that a single mutation outside of the polymerase active site and inside of the p51 subunit of RT can significantly influence nucleotide selectivity.

scholarly journals HLA-B57/B*5801 Human Immunodeficiency Virus Type 1 Elite Controllers Select for Rare Gag Variants Associated with Reduced Viral Replication Capacity and Strong Cytotoxic T-Lymphotye Recognition

2008 ◽  
Vol 83 (6) ◽  
pp. 2743-2755 ◽  
Author(s):  
Toshiyuki Miura ◽  
Mark A. Brockman ◽  
Arne Schneidewind ◽  
Michael Lobritz ◽  
Florencia Pereyra ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Replication ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Viral Fitness ◽  
Replication Capacity ◽  
Elite Controllers ◽  
Immunodeficiency Virus ◽  
Viral Replication Capacity

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) elite controllers (EC) maintain viremia below the limit of commercial assay detection (<50 RNA copies/ml) in the absence of antiviral therapy, but the mechanisms of control remain unclear. HLA-B57 and the closely related allele B*5801 are particularly associated with enhanced control and recognize the same Gag240-249 TW10 epitope. The typical escape mutation (T242N) within this epitope diminishes viral replication capacity in chronically infected persons; however, little is known about TW10 epitope sequences in residual replicating viruses in B57/B*5801 EC and the extent to which mutations within this epitope may influence steady-state viremia. Here we analyzed TW10 in a total of 50 B57/B*5801-positive subjects (23 EC and 27 viremic subjects). Autologous plasma viral sequences from both EC and viremic subjects frequently harbored the typical cytotoxic T-lymphocyte (CTL)-selected mutation T242N (15/23 sequences [65.2%] versus 23/27 sequences [85.1%], respectively; P = 0.18). However, other unique mutants were identified in HIV controllers, both within and flanking TW10, that were associated with an even greater reduction in viral replication capacity in vitro. In addition, strong CTL responses to many of these unique TW10 variants were detected by gamma interferon-specific enzyme-linked immunospot assay. These data suggest a dual mechanism for durable control of HIV replication, consisting of viral fitness loss resulting from CTL escape mutations together with strong CD8 T-cell immune responses to the arising variant epitopes.

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