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1.
ACS Nano ; 18(27): 18036-18045, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38916252

RESUMO

Cation exchange is a versatile method for modifying the material composition and properties of nanostructures. However, control of the degree of exchange and material properties is difficult at the single-particle level. Successive cation exchange from CdSe to Ag2Se has been utilized here on the same individual nanowires to monitor the change of electronic properties in field-effect transistor devices. The transistors were fabricated by direct synthesis of CdSe nanowires on prepatterned substrates followed by optical lithography. The devices were then subjected to cation exchange by submerging them in an exchange solution containing silver nitrate. By removal of the devices from solution and probing the electrical transport properties at different times, the change in electronic properties of individual nanowires could be monitored throughout the entire exchange reaction from CdSe to Ag2Se. Transistor characterization revealed that the electrical conductivity can be tuned by up to 8 orders of magnitude and the charge-carrier mobility by 7 orders of magnitude. While analysis of the material composition by energy dispersive X-ray spectroscopy confirmed successful cation exchange from CdSe to Ag2Se, X-ray fluorescence spectroscopy proved that cation exchange also took place below the contacts. The method presented here demonstrates an efficient way to tune the material composition and access the resulting properties nondestructively at the single-particle level. This approach can be readily applied to many other material systems and can be used to study the electrical properties of nanostructures as a function of material composition or to optimize nanostructure-based devices after fabrication.

2.
Front Public Health ; 11: 1166913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614457

RESUMO

Background: Climate change leads to more frequent and severe extreme weather events including floods, heatwaves, heavy rainfalls, and droughts. In contrast to the majority of research on weather extremes in sub-Saharan Africa, which focus primarily on how a lack of rainfall causes droughts, this paper aims to elucidate the effect of flooding on harvest failure in rural Burkina Faso. Methods: We conducted a case study in north-western Nouna, Burkina Faso, between August and December 2021 covering a study population of n = 180 participants. The study comprised four components: (i) interviews with farmers (n = 180) on whether any of their fields had been inundated and if so, on harvest loss on these fields; (ii) determining the feasibility of using Sentinel-2 satellite images to validate study participants reports of floods; (iii) characterizing short-term weather including frequency and duration, of extreme rainfall events within the study area, as well as comparing cumulative rainfall (long-term) over the past 50 years; and (v), estimating both the food energy and economic loss of harvest failure due to flooding. Results: 49% of interviewed farmers (n = 88) reported that floods had damaged at least one of their fields. Some fields (n = 13, 7%) had no harvest due to flooding, while some farmers (n = 14, 8%) had lost part of their harvest. Images from the Sentinel-2-Satellite indicated that reported and remotely observed flooding were consistent. According to time series of data from the local weather station, there has been an increase irregular rainfall distribution and at the same time of cumulative annual rainfall in Nouna. Furthermore, a first illustrative calculation allowed us to estimate the amount of energy lost when one hectare of a common crop is flooded. Conclusion: This case study demonstrated that flood-related harvest failures leading to crop losses in sub-Saharan Africa, exemplified by Burkina Faso, are likely to be substantial. This study serves as a proof-of-principle for flooding effects on food security. This could provide more detail for agricultural adaptation and mitigation strategies. Inundation-vulnerable fields need alternative and novel management practices, which may only be effectively implemented if agricultural institutions and national policy-making bodies receive evidence of flooding e.g., from remote sensing.


Assuntos
Mudança Climática , Inundações , Humanos , Burkina Faso , Tempo (Meteorologia) , Agricultura
3.
Front Public Health ; 11: 1153559, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304117

RESUMO

Background: Climate change significantly impacts health in low-and middle-income countries (LMICs), exacerbating vulnerabilities. Comprehensive data for evidence-based research and decision-making is crucial but scarce. Health and Demographic Surveillance Sites (HDSSs) in Africa and Asia provide a robust infrastructure with longitudinal population cohort data, yet they lack climate-health specific data. Acquiring this information is essential for understanding the burden of climate-sensitive diseases on populations and guiding targeted policies and interventions in LMICs to enhance mitigation and adaptation capacities. Objective: The objective of this research is to develop and implement the Change and Health Evaluation and Response System (CHEERS) as a methodological framework, designed to facilitate the generation and ongoing monitoring of climate change and health-related data within existing Health and Demographic Surveillance Sites (HDSSs) and comparable research infrastructures. Methods: CHEERS uses a multi-tiered approach to assess health and environmental exposures at the individual, household, and community levels, utilizing digital tools such as wearable devices, indoor temperature and humidity measurements, remotely sensed satellite data, and 3D-printed weather stations. The CHEERS framework utilizes a graph database to efficiently manage and analyze diverse data types, leveraging graph algorithms to understand the complex interplay between health and environmental exposures. Results: The Nouna CHEERS site, established in 2022, has yielded significant preliminary findings. By using remotely-sensed data, the site has been able to predict crop yield at a household level in Nouna and explore the relationships between yield, socioeconomic factors, and health outcomes. The feasibility and acceptability of wearable technology have been confirmed in rural Burkina Faso for obtaining individual-level data, despite the presence of technical challenges. The use of wearables to study the impact of extreme weather on health has shown significant effects of heat exposure on sleep and daily activity, highlighting the urgent need for interventions to mitigate adverse health consequences. Conclusion: Implementing the CHEERS in research infrastructures can advance climate change and health research, as large and longitudinal datasets have been scarce for LMICs. This data can inform health priorities, guide resource allocation to address climate change and health exposures, and protect vulnerable communities in LMICs from these exposures.


Assuntos
Mudança Climática , Projetos de Pesquisa , Humanos , Atividades Cotidianas , África , Algoritmos
4.
Environ Int ; 178: 108032, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37352580

RESUMO

INTRODUCTION: Numerous studies have shown associations between daily concentrations of fine particles (e.g., particulate matter with an aerodynamic diameter ≤2.5 µm; PM2.5) and morbidity. However, evidence for ultrafine particles (UFP; particles with an aerodynamic diameter of 10-100 nm) remains conflicting. Therefore, we aimed to examine the short-term associations of UFP with five cause-specific hospital admission endpoints for Leipzig, Dresden, and Augsburg, Germany. MATERIAL AND METHODS: We obtained daily counts of (cause-specific) cardiorespiratory hospital admissions between 2010 and 2017. Daily average concentrations of UFP, total particle number (PNC; 10-800 nm), and black carbon (BC) were measured at six sites; PM2.5 and nitrogen dioxide (NO2) were obtained from monitoring networks. We assessed immediate (lag 0-1), delayed (lag 2-4, lag 5-7), and cumulative (lag 0-7) effects by applying station-specific confounder-adjusted Poisson regression models. We then used a novel multi-level meta-analytical method to obtain pooled risk estimates. Finally, we performed two-pollutant models to investigate interdependencies between pollutants and examined possible effect modification by age, sex, and season. RESULTS: UFP showed a delayed (lag 2-4) increase in respiratory hospital admissions of 0.69% [95% confidence interval (CI): -0.28%; 1.67%]. For other hospital admission endpoints, we found only suggestive results. Larger particle size fractions, such as accumulation mode particles (particles with an aerodynamic diameter of 100-800 nm), generally showed stronger effects (respiratory hospital admissions & lag 2-4: 1.55% [95% CI: 0.86%; 2.25%]). PM2.5 showed the most consistent associations for (cardio-)respiratory hospital admissions, whereas NO2 did not show any associations. Two-pollutant models showed independent effects of PM2.5 and BC. Moreover, higher risks have been observed for children. CONCLUSIONS: We observed clear associations with PM2.5 but UFP or PNC did not show a clear association across different exposure windows and cause-specific hospital admissions. Further multi-center studies are needed using harmonized UFP measurements to draw definite conclusions on the health effects of UFP.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Criança , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Cidades , Poluição do Ar/análise , Dióxido de Nitrogênio , Tamanho da Partícula , Hospitais
5.
Am J Respir Crit Care Med ; 207(10): 1334-1344, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36877186

RESUMO

Rationale: Exposure to ambient air pollution has been associated with adverse effects on morbidity and mortality. However, the evidence for ultrafine particles (UFPs; 10-100 nm) based on epidemiological studies remains scarce and inconsistent. Objectives: We examined associations between short-term exposures to UFPs and total particle number concentrations (PNCs; 10-800 nm) and cause-specific mortality in three German cities: Dresden, Leipzig, and Augsburg. Methods: We obtained daily counts of natural, cardiovascular, and respiratory mortality between 2010 and 2017. UFPs and PNCs were measured at six sites, and measurements of fine particulate matter (PM2.5; ⩽2.5 µm in aerodynamic diameter) and nitrogen dioxide were collected from routine monitoring. We applied station-specific confounder-adjusted Poisson regression models. We investigated air pollutant effects at aggregated lags (0-1, 2-4, 5-7, and 0-7 d after UFP exposure) and used a novel multilevel meta-analytical method to pool the results. Additionally, we assessed interdependencies between pollutants using two-pollutant models. Measurements and Main Results: For respiratory mortality, we found a delayed increase in relative risk of 4.46% (95% confidence interval, 1.52 to 7.48%) per 3,223-particles/cm3 increment 5-7 days after UFP exposure. Effects for PNCs showed smaller but comparable estimates consistent with the observation that the smallest UFP fractions showed the largest effects. No clear associations were found for cardiovascular or natural mortality. UFP effects were independent of PM2.5 in two-pollutant models. Conclusions: We found delayed effects for respiratory mortality within 1 week after exposure to UFPs and PNCs but no associations for natural or cardiovascular mortality. This finding adds to the evidence on the independent health effects of UFPs.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doenças Respiratórias , Humanos , Material Particulado/efeitos adversos , Material Particulado/análise , Cidades , Causas de Morte , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Doenças Respiratórias/induzido quimicamente , Doenças Respiratórias/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise
6.
Environ Sci Pollut Res Int ; 29(58): 87950-87968, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35829889

RESUMO

Performance of aeration systems in wastewater treatment plants (WWTP) under process conditions can be monitored with off-gas tests. The ex situ off-gas method transfers activated sludge from an adjacent aeration tank into aerated columns to determine oxygen transfer parameters (e.g., the α-factor). This method is an alternative to in situ off-gas testing with hoods at the tank surface; however, its application and measurement uncertainty have not been examined yet. We outline our experience from long-term off-gas testing with two pilot-scale test reactors (8.3 m3 volume). Global variance-based sensitivity analysis using Sobol' indices revealed oxygen concentration in off-gas and dissolved oxygen as the most important input quantities to determine α-factors accurately. Measurement uncertainty of other instruments was negligible. These findings are transferable to in situ off-gas hoods because the methods are similar. Random measurement error of α-factors was estimated with uncertainty analysis and comparison measurements to a relative standard deviation of about ± 2.8% for our ex situ pilot setup. Diffuser fouling, biofilm growth, or sensor drift caused systematic errors avoidable by maintenance. Additional mixing of bubble column due to sludge inflow into ex situ tanks led to a systematic overestimation of α-factors at lower airflow rates. Hence, the ex situ off-gas method is not suitable to determine α-factors for the design of aeration systems but offers unique possibilities for research of oxygen transfer dynamics and development of aeration equipment because ex situ columns can be operated independently from a full-scale activated sludge tank.


Assuntos
Esgotos , Purificação da Água , Eliminação de Resíduos Líquidos/métodos , Incerteza , Purificação da Água/métodos , Oxigênio/análise , Reatores Biológicos
7.
Psychol Assess ; 34(8): 717-730, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35343736

RESUMO

Psychopathy is deemed an important construct in forensic settings. Consequently, its theoretical basis and measurement are relevant to researchers but also to criminal justice administrators and decision-makers. The Elemental Psychopathy Assessment (EPA) is a recently developed self-report scale designed to measure psychopathic traits based on the five-factor model, one of the most comprehensive frameworks of general personality. Recent research provided initial support for the reliability and construct validity of the EPA, and exploratory factor analyses yielded a four-factor structure across different samples from the United States. Independent and confirmatory assessments of the construct validity and factor structure of the EPA are, however, pending. Across three independent, non-American samples (accumulated N = 1,803), we examined its content and factorial validity. We corroborated the proposed four-factor structure by means of both exploratory and confirmatory factor analyses (CFA). Item-based CFA further indicated that the EPA items adequately measure the scales that they were initially assigned to. Taken together, the EPA is a psychometrically sound assessment tool for psychopathy. Given its substantial overlap with basic units of personality, the EPA represents a valid instrument to investigate psychopathy from a dimensional, trait-based perspective. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Transtorno da Personalidade Antissocial , Transtornos da Personalidade , Transtorno da Personalidade Antissocial/diagnóstico , Humanos , Inventário de Personalidade , Psicometria/métodos , Reprodutibilidade dos Testes
8.
Int J Hyg Environ Health ; 235: 113752, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34020228

RESUMO

BACKGROUND: Concentrations of persistent organic pollutants (POPs) have been associated with an increased type 2 diabetes (T2D) risk. It remains unclear whether POPs are also associated with the risk of diabetes complications including neuropathy and evidence on this topic is scarce. We aimed to investigate the hypothesis that low-dose background concentrations of POPs were positively associated with distal sensorimotor polyneuropathy (DSPN). METHODS: This cross-sectional study was based on data from the second follow-up (FF4, 2013-2014, N = 2279) of the population-based KORA S4 study (Augsburg, Germany). The study sample consisted of 200 participants, including four groups of 50 persons each with known T2D, prediabetes, newly diagnosed diabetes, and normal glucose tolerance (NGT) based on an oral glucose tolerance test. We analyzed the association of six most abundant serum concentrations of POPs, including polychlorinated biphenyls (PCBs) as well as organochlorine (OC) pesticides, with DSPN by multivariable logistic regression adjusted for age, sex, glycaemic status, body mass index, physical activity, smoking and alcohol consumption. We assessed effect modification by age, sex, glycaemic status and obesity and conducted two-pollutant models to check the robustness of the estimates. RESULTS: For all pollutants, the main models indicated no significant association of having DSPN but pointed to rather decreased odds for DSPN. Two-pollutant models supported these findings, though only the association between the combination of PCB-138 and beta-hexachlorocyclohexane (ß-HCH) (OR: 0.59; 95% CI: 0.35-0.99) with DSPN became significant. No effect modification was found by age, sex, glycaemic status and obesity. CONCLUSION: Low-dose concentrations of POPs were not associated with increased odds of having DSPN in T2D, prediabetes and NGT.


Assuntos
Diabetes Mellitus Tipo 2 , Poluentes Ambientais , Hidrocarbonetos Clorados , Bifenilos Policlorados , Estado Pré-Diabético , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Poluentes Orgânicos Persistentes , Estado Pré-Diabético/epidemiologia
9.
Nanoscale ; 13(17): 8017-8023, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33899075

RESUMO

Silver selenide (Ag2Se) is a promising material for applications as a solid-state electrolyte, with a superionic phase transition at 133 °C. Here, we studied the temperature dependent transport properties of single Ag2Se nanowires in a transistor geometry, which allowed us to determine charge carrier type, concentration, and mobility below and above the superionic phase transition temperature. We found the majority charge carriers to be n-type in the temperature range of 30-150 °C. Across the superionic phase-transition, we observed a sudden increase in conductivity by about 30%, which was accompanied by an increase in charge carrier density by about 200% and a decrease in mobility by about 45%. Interestingly, the size dependent shift of the transition temperatures to below 100 °C in our wires is much more pronounced than for nanocrystals of comparable size. This surprising and potentially useful effect could be caused by changes in crystal structure arising from the synthesis process.

10.
Zootaxa ; 4892(1): zootaxa.4892.1.1, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33311101

RESUMO

Morocco is a well known hot-spot of biodiversity in the Mediterranean basin. While some taxa like vascular plants are relatively well recorded, important groups of pollinators like bees are still understudied. This article presents an updated checklist of the bee species of Morocco and includes a summary of global and regional distribution of each species. A total of 961 species belonging to six bee families and 68 genera are recorded: Andrenidae (8 genera, 217 species); Apidae (15 genera, 241 species); Colletidae (2 genera, 74 species), Halictidae (12 genera, 144 species), Megachilidae (28 genera, 271 species) and Melittidae (3 genera, 14 species). Among them, 67 species are recorded for the first time in Morocco. Around 70% of the bee fauna of Morocco consists of widespread Palaearctic species. Only 18% of Moroccan species recorded are restricted to North Africa and 8% are Moroccan single-country endemics (81 species). Afrotropical elements in the Moroccan fauna are few, with only 3% of Morocco species co-occuring in that region. This checklist is intended to stimulate new regional research on bees including their taxonomy and biogeography. As many groups of bees have been understudied, discovery of new species for science and new records for the country can be expected. Additional research including inventorying, monitoring, and integrative taxonomic studies are needed to develop a comprehensive strategy for bee conservation in Morocco.


Assuntos
Abelhas , Himenópteros , Animais , Sequência de Bases , Himenópteros/genética , Marrocos
11.
Zookeys ; 937: 31-88, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547298

RESUMO

The available information about the cleptoparasitic bees of the genus Sphecodes in Southeast Asia is summarized. Thirty-one species are currently known from this area. Four new species are described: Sphecodes discoverlifei Astafurova & Proshchalykin, sp. nov. (Laos), S. engeli Astafurova & Proshchalykin, sp. nov. (Laos, Vietnam), S. ilyadadaria Astafurova, sp. nov. (Indonesia), and S. pseudoredivivus Astafurova & Proshchalykin, sp. nov. (Laos). Nine species are newly recorded from South East Asia: S. chaprensis Blüthgen, 1927 (Laos), S. howardi Cockerell, 1922 (Malaysia, Myanmar, Thailand), S. kershawi Perkins, 1921 (Indonesia, Malaysia, Myanmar, Thailand), S. laticeps Meyer, 1920 (Thailand, Vietnam), S. montanus Smith, 1879 (Laos), S. sauteri Meyer, 1925 (Laos), S. sikkimensis Blüthgen, 1927 (Laos, Myanmar), S. simlaensis Blüthgen, 1924 (Laos), and S. turneri Cockerell, 1916 (Laos). Based on type specimens, new synonymies have been proposed for Sphecodes kershawi Perkins, 1921 = S. javanensis Blüthgen, 1927, syn. nov.; S. simlaensis Blüthgen, 1924 = S. simlaellus Blüthgen, 1927, syn. nov.; S. laticeps Meyer, 1920 = S. biroi mariae Cockerell, 1930, syn. nov. Lectotypes are designated for Sphecodes biroi Friese, 1909, S. simlaellus Blüthgen, 1927, and S. laticeps Meyer, 1920. The female of Sphecodes sauteri Meyer, 1925, and the male of S. turneri Cockerell, 1916 are described for the first time.

12.
Zookeys ; 872: 13-40, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496884

RESUMO

This study summarises all available information on the bees of the genus Sphecodes in the Arabian Peninsula and surrounding countries (Israel, Jordan, and Syria). Twenty-six species are currently known from this area, while five species are newly recorded from the Arabian Peninsula: Sphecodes atlanticus Warncke, 1992 (Saudi Arabia, Yemen), S. intermedius Blüthgen, 1923 (UAE), S. nomioidis Pesenko, 1979 (UAE, Oman), S. puncticeps Thomson, 1870 (Saudi Arabia), and S. turanicus Astafurova & Proshchalykin, 2017 (Saudi Arabia). In addition, twelve species are newly recorded from Jordan, six for Syria, and four for Israel. The female of S. atlanticus Warncke, 1992 and the male of S. dathei Schwarz, 2010 are here described for the first time and a lectotype is designated for S. intermedius Blüthgen, 1923.

13.
Zootaxa ; 4441(1): 76-88, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-30314021

RESUMO

Following a previously published study on Central Asian species of Sphecodes bees we here present a further report on 20 rarely recorded and little known species. This brings to 34 the number of species of Sphecodes known from this region, with two of them recorded for the first time: Sphecodes scabricollis Wesmael, 1835 and S. hakkariensis Warncke, 1992. Sphecodes sandykachis Astafurova Proshchalykin, sp. n. is described from Turkmenistan and Uzbekistan. Sphecodes atlassa Warncke, 1992, stat. nov. and S. hakkariensis Warncke, 1992, stat. nov. are raised to full species level.


Assuntos
Distribuição Animal , Himenópteros , Animais , Abelhas , Turcomenistão , Uzbequistão
14.
Mol Cell Endocrinol ; 460: 181-188, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28756250

RESUMO

Vaspin expression is increased in white adipose tissue (WAT) of diet-induced obese mice and rats and is supposed to compensate HFD-induced inflammatory processes and insulin resistance in adipose tissue by counteracting pro-inflammatory gene expression in obesity. Multiple studies have also demonstrated strong anti-inflammatory effects in vascular and skin cells. Here, we used vaspin treated 3T3-L1 murine adipocytes as well as 3T3-L1 cells with stable vaspin expression to investigate the effect of exogenous and endogenous vaspin on inflammatory processes and insulin signaling in adipocytes. Our stably transfected cells secreted significant amounts of vaspin which was in the physiological range of ∼0.5 ng/ml in cell supernatants. Adipocyte differentiation was not affected by vaspin as expression of adipogenic marker genes as well as lipid accumulation after full differentiation was similar to control cells. We found that IL-1ß induced expression and secretion of pro-inflammatory cytokines, such as IL-6, MCP1 and TNFα was significantly blunted in vaspin expressing 3T3-L1 cells. Treatment of 3T3-L1 cells with exogenous vaspin resulted in reduced cytokine-induced activation of the intracellular and pro-inflammatory NFκB signaling cascades (IKKα/ß, IκB and NFκB). Moreover, endogenous vaspin positively affected insulin signaling by increasing insulin-stimulated phosphorylation of the key mediator protein kinase B (AKT). Together, we demonstrate anti-inflammatory effects of vaspin in 3T3-L1 adipocytes as well as increased insulin signaling by endogenous expression or exogenous treatment. The results provide evidence for potent anti-inflammatory action of vaspin not only in vascular cells but also in adipose tissue.


Assuntos
Adipócitos/metabolismo , Adipócitos/patologia , Citocinas/efeitos adversos , Inflamação/patologia , NF-kappa B/metabolismo , Serpinas/farmacologia , Transdução de Sinais , Células 3T3-L1 , Animais , Diferenciação Celular/efeitos dos fármacos , Quimiocinas/efeitos adversos , Humanos , Insulina/farmacologia , Camundongos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo
15.
Antiviral Res ; 107: 16-22, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24747042

RESUMO

The role of mutations in the thymidine kinase (TK, UL23) and DNA polymerase (pol, UL30) genes of herpes simplex virus (HSV) for development of different resistance phenotypes has to be exactly determined before genotypic resistance testing can be implemented in patient's care. Furthermore, the occurrence of cross-resistance is of utmost clinical importance. In this study, clinical HSV-1 isolates obtained between 2004 and 2011 from 26 patients after stem cell transplantation were examined in parallel by phenotypic and genotypic resistance testing. Thirteen isolates, which were phenotypically cross-resistant to acyclovir (ACV), penciclovir (PCV) and brivudin (BVDU), exhibited consistently frameshift or non-synonymous mutations in the TK gene known to confer resistance. One of these mutations (insertion of C at the nucleotide positions 1061-1065) has not been described before. Seven strains, phenotypically resistant to ACV and PCV and, except one each, sensitive to BVDU and resistant to foscarnet (FOS), carried uniformly resistance-related substitutions in the DNA pol gene. Finally, 3 isolates, resistant to ACV, PCV and 2 out of these also resistant to BVDU, had known but also unclear substitutions in the TK and DNA pol genes, and 3 isolates were completely sensitive. In conclusion, clinical ACV-resistant HSV-1 isolates, carrying resistance-associated mutations in the TK gene, can be regarded as cross-resistant to other nucleoside analogs such as BVDU. In contrast, clinical FOS-resistant HSV-1 strains which are cross-resistant to ACV may be sensitive to BVDU. This has to be considered for drug changes in antiviral treatment in case of ACV resistance.


Assuntos
DNA Polimerase Dirigida por DNA/genética , Farmacorresistência Viral , Exodesoxirribonucleases/genética , Herpes Simples/virologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/enzimologia , Polimorfismo de Nucleotídeo Único , Timidina Quinase/genética , Proteínas Virais/genética , Aciclovir/análogos & derivados , Aciclovir/farmacologia , Adolescente , Adulto , Idoso , Antivirais/farmacologia , Bromodesoxiuridina/análogos & derivados , Bromodesoxiuridina/farmacologia , Criança , DNA Viral/química , DNA Viral/genética , Feminino , Mutação da Fase de Leitura , Guanina , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/isolamento & purificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutagênese Insercional , Mutação de Sentido Incorreto , Mutação Puntual , Análise de Sequência de DNA , Adulto Jovem
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