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1.
Clin Infect Dis ; 78(5): 1222-1231, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38393822

RESUMO

BACKGROUND: Tularemia is an important reemerging disease with a multimodal transmission pattern. Treatment outcomes of current recommended antibiotic regimens (including ciprofloxacin and doxycycline) remain unclear. In this retrospective cohort study, we report clinical, laboratory, geographical, and treatment outcomes of laboratory-confirmed tularemia cases over an 11-year period in Northern Sweden. METHODS: Data from reported tularemia cases (aged >10 years at time of study) in Norrbotten county between 2011 and 2021 were collected through review of electronic medical records and participant questionnaires; 415 of 784 accepted participation (52.9%). Of these, 327 were laboratory-confirmed cases (serology and/or polymerase chain reaction). A multivariable logistic regression model was used to investigate variables associated with retreatment. RESULTS: Median age of participants was 54 years (interquartile range [IQR], 41.5-65) and 49.2% were female. Although ulceroglandular tularemia was the predominant form (n = 215, 65.7%), there were several cases of pulmonary tularemia (n = 40; 12.2%). Inflammatory markers were largely nonspecific, with monocytosis frequently observed (n = 36/75; 48%). Tularemia was often misdiagnosed on presentation (n = 158, 48.3%), with 65 (19.9%) receiving initial inappropriate antibiotics and 102 (31.2%) retreated. Persistent lymphadenopathy was infrequent (n = 22, 6.7%), with 10 undergoing surgical interventions. In multivariable analysis of variables associated with retreatment, we highlight differences in time until receiving appropriate antibiotics (8 [IQR, 3.25-20.75] vs 7 [IQR, 4-11.25] days; adjusted P = .076), and doxycycline-based treatment regimen (vs ciprofloxacin; adjusted P = .084), although this was not significant after correction for multiple comparisons. CONCLUSIONS: We comprehensively summarize clinical, laboratory, and treatment outcomes of type B tularemia. Targeting tularemia requires clinical awareness, early diagnosis, and timely commencement of treatment for an appropriate duration.


Assuntos
Antibacterianos , Doxiciclina , Tularemia , Humanos , Tularemia/tratamento farmacológico , Tularemia/diagnóstico , Tularemia/epidemiologia , Suécia/epidemiologia , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Masculino , Adulto , Idoso , Resultado do Tratamento , Doxiciclina/uso terapêutico , Francisella tularensis/isolamento & purificação , Ciprofloxacina/uso terapêutico , Adulto Jovem
2.
Acta Derm Venereol ; 103: adv12616, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987625

RESUMO

Whether response to an interleukin (IL-17) inhibitor is different in patients with previous exposure to an IL-17 inhibitor compared with patients with exposure to biologics with other cytokine targets remains to be elucidated. Therefore, the aim of this study was to  assess whether previous exposure to an IL-17A inhibitor was associated with worse response than exposure to (an)other biologic(s). All patients in the DERMBIO register treated with an IL-17A inhibitor (secukinumab or ixekizumab) were included. With an absolute Psoriasis Area and Severity Index (PASI) ≤ 2 as response, the proportion of responders treated with IL-17A inhibitors was assessed in patients previously treated with another IL-17A inhibitor and compared with patients with previous exposure to (an)other biologic(s), using a χ2 test. In total, 100, 93 and 83 patients with  previous exposure to an IL-17A inhibitor and 414, 372 and 314 patients with previous exposure to (an) other biologic(s) were assessed after 3, 6 and 12 months, respectively. No differences in the proportion of  patients achieving PASI ≤ 2 were observed between the 2 groups after 3 months (54% vs 57%, p = 0.59), 6months (70% vs 66%, p = 0.42) and 12 months (69% vs 60%, p = 0.14). In conclusion, when treating patients with IL-17A inhibitors the cytokine target of the previous biologic does not appear to affect the  response.


Assuntos
Produtos Biológicos , Psoríase , Humanos , Interleucina-17 , Citocinas , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Produtos Biológicos/efeitos adversos , Dinamarca
3.
Actas Dermosifiliogr ; 114(3): 240-246, 2023 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36370831

RESUMO

Cherry angiomas are the most common vascular tumors of the skin. They are particularly prevalent in the general population and become more common with age. Although an association with cancer was suggested at the end of the 19th century, when these tumors were first described, it could not be demonstrated. For many decades, therefore, cherry angiomas were considered to have no clinical relevance other than their association with age. A number of studies in recent years, however, have shown a link between cherry angiomas and exposure to various toxic substances and medications, benign and malignant diseases, and immunosuppression, rekindling interest in these lesions and providing clues for a better understanding of their etiology, pathophysiology, and clinical relevance.


Assuntos
Hemangioma Capilar , Hemangioma , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/patologia , Hemangioma/patologia , Hemangioma Capilar/patologia , Pele/patologia
4.
BMC Biol ; 19(1): 94, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952283

RESUMO

BACKGROUND: The black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on 15 novel microsatellite markers, we genotyped and analysed 2862 individuals from 150 wild and captive populations originating from 57 countries on seven subcontinents. RESULTS: We identified 16 well-distinguished genetic clusters indicating substantial global population structure. The data revealed genetic hotspots in central South America and successive northwards range expansions within the indigenous ranges of the Americas. Colonisations and naturalisations of largely unique genetic profiles occurred on all non-native continents, either preceded by demographically independent founder events from various single sources or involving admixture scenarios. A decisive primarily admixed Polynesian bridgehead population serially colonised the entire Australasian region and its secondarily admixed descendants successively mediated invasions into Africa and Europe. Conversely, captive populations from several continents traced back to a single North American origin and exhibit considerably reduced genetic diversity, although some farmed strains carry distinct genetic signatures. We highlight genetic footprints characteristic of progressing domestication due to increasing socio-economic importance of H. illucens, and ongoing introgression between domesticated strains globally traded for large-scale farming and wild populations in some regions. CONCLUSIONS: We document the dynamic population genetic history of a cosmopolitan dipteran of South American origin shaped by striking geographic patterns. These reflect both ancient dispersal routes, and stochastic and heterogeneous anthropogenic introductions during the last century leading to pronounced diversification of worldwide structure of H. illucens. Upon the recent advent of its agronomic commercialisation, however, current human-mediated translocations of the black soldier fly largely involve genetically highly uniform domesticated strains, which meanwhile threaten the genetic integrity of differentiated unique local resources through introgression. Our in-depth reconstruction of the contemporary and historical demographic trajectories of H. illucens emphasises benchmarking potential for applied future research on this emerging model of the prospering insect-livestock sector.


Assuntos
Dípteros , Ração Animal/análise , Animais , Demografia , Dípteros/genética , Genética Populacional , Humanos , Larva
5.
J Eur Acad Dermatol Venereol ; 34(10): 2295-2302, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32163215

RESUMO

BACKGROUND: Cutaneous melanoma patients have an increased risk of developing other neoplasms, especially cutaneous neoplasms and other melanomas. Identifying factors associated with an increased risk might be useful in the development of melanoma guidelines. OBJECTIVES: To identify risk factors related to the development of a second primary melanoma in a series of patients diagnosed with sporadic melanoma and to establish the estimated incidence rate. METHODS: A longitudinal study based on prospective follow-up information of patients diagnosed with sporadic cutaneous melanoma at our centre from 2000 to 2015 was performed. Cumulative incidence was estimated based on competing risk models, and the association of characteristics with the risk of a second melanoma was performed by Cox proportional hazard models. RESULTS: Out of 1447 patients included in the study, after a median follow-up of 61 months, 55 patients (3.8%) developed a second melanoma. Fair hair colour, more than 100 common melanocytic nevi and the presence of more than 50 cherry angiomas were independently associated with the development of a second melanoma. The site and the histological subtype of the first and second melanomas were not consistent. The second melanomas were thinner than the first ones. CONCLUSIONS: Fair-haired and multiple-nevi patients might benefit from more intensive prevention measures. The finding of cherry angiomas as a risk factor suggests that these lesions could be markers of skin sun damage in the setting of certain degree of genetic susceptibility.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Estudos Longitudinais , Melanoma/epidemiologia , Estudos Prospectivos , Fatores de Risco , Neoplasias Cutâneas/epidemiologia
6.
Nutr Metab Cardiovasc Dis ; 29(7): 676-683, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31078364

RESUMO

BACKGROUND AND AIMS: There is ongoing controversy about the effect of a low to moderate alcohol consumption on atrial fibrillation (AF). Our aim is to assess the association between adherence to a Mediterranean alcohol drinking pattern and AF incidence. METHODS AND RESULTS: A total 6527 out of the 7447 participants in the PREDIMED trial met our inclusion criteria. A validated frequency food questionnaire was used to measure alcohol consumption. Participants were classified as non-drinkers, Mediterranean alcohol drinking pattern (MADP) (10-30 g/d in men and 5-15 g/day in women, preferably red wine consumption with low spirits consumption), low-moderate drinking (<30 g/day men y and < 15 g/day women), and heavy drinking. We performed multivariable Cox regression models to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) of incident AF according to alcohol drinking patterns. After a mean follow up of 4.4 years, 241 new incident AF cases were confirmed. Alcohol consumption was not associated to AF incidence among low-moderate drinkers (HR: 0.96; 95%CI: 0.67-1.37), adherents to MADP (HR: 1.15 95%CI: 0.75-1.75), or heavy drinkers (HR: 0.92; 95%CI: 0.53-1.58), compared with non-drinkers. CONCLUSIONS: In a high cardiovascular risk adult population, a Mediterranean alcohol consumption pattern (low to moderate red wine consumption) was not associated with an increased incidence of AF. CLINICAL TRIALS: URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35739639.


Assuntos
Consumo de Bebidas Alcoólicas/tendências , Fibrilação Atrial/epidemiologia , Dieta Mediterrânea , Comportamento Alimentar , Vinho , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Fibrilação Atrial/diagnóstico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Espanha/epidemiologia , Fatores de Tempo , Vinho/efeitos adversos
8.
Biochim Biophys Acta ; 1860(6): 1265-71, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26971857

RESUMO

BACKGROUND: Bacillus anthracis is the causative agent of anthrax, a disease associated with a very high mortality rate in its invasive forms. METHODS: We studied a number of ebselen analogs as inhibitors of B. anthracis thioredoxin reductase and their antibacterial activity on Bacillus subtilis, Staphylococcus aureus, Bacillus cereus and Mycobacterium tuberculosis. RESULTS: The most potent compounds in the series gave IC(50) values down to 70 nM for the pure enzyme and minimal inhibitory concentrations (MICs) down to 0.4 µM (0.12 µg/ml) for B. subtilis, 1.5 µM (0.64 µg/ml) for S. aureus, 2 µM (0.86 µg/ml) for B. cereus and 10 µg/ml for M. tuberculosis. Minimal bactericidal concentrations (MBCs) were found at 1-1.5 times the MIC, indicating a general, class-dependent, bactericidal mode of action. The combined bacteriological and enzymological data were used to construct a preliminary structure-activity-relationship for the benzoisoselenazol class of compounds. When S. aureus and B. subtilis were exposed to ebselen, we were unable to isolate resistant mutants on both solid and in liquid medium suggesting a high resistance barrier. CONCLUSIONS: These results suggest that ebselen and analogs thereof could be developed into a novel antibiotic class, useful for the treatment of infections caused by B. anthracis, S. aureus, M. tuberculosis and other clinically important bacteria. Furthermore, the high barrier against resistance development is encouraging for further drug development. GENERAL SIGNIFICANCE: We have characterized the thioredoxin system from B. anthracis as a novel drug target and ebselen and analogs thereof as a potential new class of antibiotics targeting several important human pathogens.


Assuntos
Antibacterianos/farmacologia , Azóis/farmacologia , Bacillus anthracis/enzimologia , Bacillus/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Sequência de Aminoácidos , Isoindóis , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular
9.
Osteoporos Int ; 27(5): 1747-54, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26659066

RESUMO

UNLABELLED: The study aimed to prospectively evaluate if serum calcium is related to diabetes incidence in Hong Kong Chinese. The results showed that serum calcium has a significant association with increased risk of diabetes. The result of meta-analysis reinforced our findings. INTRODUCTION: This study aimed to evaluate the association of serum calcium, including serum total calcium and albumin-corrected calcium, with incident diabetes in Hong Kong Chinese. METHODS: We conducted a retrospective cohort study in 6096 participants aged 20 or above and free of diabetes at baseline. Serum calcium was measured at baseline. Incident diabetes was determined from several electronic databases. We also searched relevant databases for studies on serum calcium and incident diabetes and conducted a meta-analysis using fixed-effect modeling. RESULTS: During 59,130.9 person-years of follow-up, 631 participants developed diabetes. Serum total calcium and albumin-corrected calcium were associated with incident diabetes in the unadjusted model. After adjusting for demographic and clinical variables, the association remained significant only for serum total calcium (hazard ratio (HR), 1.32 (95 % confidence interval (CI), 1.02-1.70), highest vs. lowest quartile). In a meta-analysis of four studies including the current study, both serum total calcium (pooled risk ratio (RR), 1.38 (95 % CI, 1.15-1.65); I (2) = 5 %, comparing extreme quantiles) and albumin-corrected calcium (pooled RR, 1.29 (95 % CI, 1.03-1.61); I (2) = 0 %, comparing extreme quantiles) were associated with incident diabetes. Penalized regression splines showed that the association of incident diabetes with serum total calcium and albumin-correlated calcium was non-linear and linear, respectively. CONCLUSIONS: Elevated serum calcium concentration is associated with incident diabetes. The mechanism underlying this association warrants further investigation.


Assuntos
Cálcio/sangue , Diabetes Mellitus Tipo 2/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/epidemiologia , Hong Kong/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/análise , Adulto Jovem
10.
Nutr Metab Cardiovasc Dis ; 26(6): 468-75, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26988650

RESUMO

BACKGROUND AND AIMS: Evidence on the association yogurt consumption and obesity is not conclusive. The aim of this study was to prospectively evaluate the association between yogurt consumption, reversion of abdominal obesity status and waist circumference change in elderly. METHODS AND RESULTS: 4545 individuals at high cardiovascular risk were prospectively followed. Total, whole-fat and low-fat yogurt consumption were assessed using food frequency questionnaires. Generalized estimating equations were used to analyze the association between yogurt consumption and waist circumference change (measured at baseline and yearly during the follow-up). Logistic regression models were used to evaluate the odds ratios (ORs) and 95% CIs of the reversion rate of abdominal obesity for each quintile of yogurt consumption compared with the lowest quintile. After multivariable adjustment, the average yearly waist circumference change in the quintiles of whole-fat yogurt consumption was: Q1: 0.00, Q2: 0.00 (-0.23 to 0.23), Q3: -0.15 (-0.42 to 0.13), Q4: 0.10 (-0.21 to 0.42), and Q5: -0.23 (-0.46 to -0.00) cm; p for trend = 0.05. The ORs for the reversion of abdominal obesity for whole-fat yogurt consumption were Q1: 1.00, Q2: 1.40 (1.04-1.90), Q3: 1.33 (0.94-1.89), Q4: 1.21 (0.83-1.77), and Q5: 1.43 (1.06-1.93); p for trend = 0.26. CONCLUSION: Total yogurt consumption was not significantly associated with reversion of abdominal obesity status and a lower waist circumference. However, consumption of whole-fat yogurt was associated with changes in waist circumference and higher probability for reversion of abdominal obesity. Therefore, it seems that whole-fat yogurt has more beneficial effects in management of abdominal obesity in elderly population at high cardiovascular risk.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta Mediterrânea , Gorduras na Dieta/administração & dosagem , Obesidade Abdominal/dietoterapia , Redução de Peso , Iogurte , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Registros de Dieta , Feminino , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade Abdominal/diagnóstico , Obesidade Abdominal/epidemiologia , Obesidade Abdominal/fisiopatologia , Razão de Chances , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Circunferência da Cintura
11.
Nutr Metab Cardiovasc Dis ; 25(2): 173-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25511785

RESUMO

BACKGROUND AND AIMS: Several studies have demonstrated a relationship between increased serum uric acid (SUA) concentrations and the prevalence of metabolic syndrome (MetS) in the oriental population. However, to the best of our knowledge, the association between SUA and MetS has never been investigated in elderly European individuals at high cardiovascular risk. The aim of this study was to conduct a cross-sectional and prospective evaluation of the associations between SUA concentrations and the MetS in elderly individuals at high cardiovascular risk. METHODS AND RESULTS: Men and women (55-80 years of age) from different PREDIMED (Prevención con DIeta MEDiterránea) recruiting centers were studied. Baseline cross-sectional (n = 4417) and prospective assessments (n = 1511) were performed. MetS was defined in accordance with the updated harmonized criteria. Anthropometric measurements and biochemical determinations were assessed at baseline and yearly during follow-up. Unadjusted and adjusted regression models were fitted to assess the risk of MetS and its components according to the levels of baseline SUA. Participants in the highest baseline sex-adjusted SUA quartile showed an increased prevalence of MetS than those in the lowest quartile, even after adjusting for potential confounders (odd ratio (OR): 2.3 (95% confidence interval (CI), 1.8-2.8); P < 0.001). Participants in the highest baseline sex-adjusted SUA quartile presented a higher incidence of new-onset MetS than those in the lowest quartile (hazard ratios (HR): 1.4 (95% CI, 1.1-1.9); P < 0.001). Participants initially free at baseline of hypertriglyceridemia (HR: 1.9 (1.6-2.4); P < 0.001), low high-density lipoprotein (HDL)-cholesterol (HR: 1.4 (1.1-1.7); P = 0.002), and hypertension components of MetS (HR: 2.0 (1.2-3.3); P = 0.008) and who were in the upper quartile of SUA had a significantly higher risk of developing these MetS components during follow-up. CONCLUSIONS: Elevated SUA concentrations are significantly associated with the development of MetS.


Assuntos
Síndrome Metabólica/sangue , Ácido Úrico/sangue , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Feminino , Seguimentos , Humanos , Hipertensão/sangue , Hipertrigliceridemia/sangue , Hiperuricemia/sangue , Hiperuricemia/complicações , Modelos Logísticos , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
13.
J Biol Chem ; 288(38): 27456-27468, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23900839

RESUMO

Trypanosoma brucei is the causing agent of African trypanosomiasis. These parasites possess a unique thiol redox system required for DNA synthesis and defense against oxidative stress. It includes trypanothione and trypanothione reductase (TryR) instead of the thioredoxin and glutaredoxin systems of mammalian hosts. Here, we show that the benzisothiazolone compound ebsulfur (EbS), a sulfur analogue of ebselen, is a potent inhibitor of T. brucei growth with a favorable selectivity index over mammalian cells. EbS inhibited the TryR activity and decreased non-protein thiol levels in cultured parasites. The inhibition of TryR by EbS was irreversible and NADPH-dependent. EbS formed a complex with TryR and caused oxidation and inactivation of the enzyme. EbS was more toxic for T. brucei than for Trypanosoma cruzi, probably due to lower levels of TryR and trypanothione in T. brucei. Furthermore, inhibition of TryR produced high intracellular reactive oxygen species. Hydrogen peroxide, known to be constitutively high in T. brucei, enhanced the EbS inhibition of TryR. The elevation of reactive oxygen species production in parasites caused by EbS induced a programmed cell death. Soluble EbS analogues were synthesized and cured T. brucei brucei infection in mice when used together with nifurtimox. Altogether, EbS and EbS analogues disrupt the trypanothione system, hampering the defense against oxidative stress. Thus, EbS is a promising lead for development of drugs against African trypanosomiasis.


Assuntos
NADH NADPH Oxirredutases/antagonistas & inibidores , Proteínas de Protozoários/antagonistas & inibidores , Tiazóis/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/enzimologia , Tripanossomíase Africana/tratamento farmacológico , Animais , Masculino , Camundongos , NADH NADPH Oxirredutases/metabolismo , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Proteínas de Protozoários/metabolismo , Tiazóis/química , Tripanossomicidas/química , Tripanossomíase Africana/enzimologia
14.
Anal Biochem ; 449: 139-46, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24374250

RESUMO

Thioredoxin (Trx) is a protein disulfide reductase that, together with nicotinamide adenine dinucleotide phosphate (NADPH) and thioredoxin reductase (TrxR), controls oxidative stress or redox signaling via thiol redox control. Human cytosolic Trx1 has Cys32 and Cys35 as the active site and three additional cysteine residues (Cys62, Cys69, and Cys73), which by oxidation generates inactive Cys62 to Cys69 two-disulfide Trx. This, combined with TrxR with a broad substrate specificity, complicates assays of mammalian Trx and TrxR. We sought to understand the autoregulation of Trx and TrxR and to generate new methods for quantification of Trx and TrxR. We optimized the synthesis of two fluorescent substrates, di-eosin-glutathione disulfide (Di-E-GSSG) and fluorescein isothiocyanate-labeled insulin (FiTC-insulin), which displayed higher fluorescence on disulfide reduction. Di-E-GSSG showed a very large increase in fluorescence quantum yield but had a relatively low affinity for Trx and was also a weak direct substrate for TrxR, in contrast to GSSG. FiTC-insulin was used to develop highly sensitive assays for TrxR and Trx. Reproducible conditions were developed for reactivation of modified Trx, commonly present in frozen or oxidized samples. Trx in cell extracts and tissue samples, including plasma and serum, were subsequently analyzed, showing highly reproducible results and allowing measurement of trace amounts of Trx.


Assuntos
Ensaios Enzimáticos/métodos , Amarelo de Eosina-(YS)/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Corantes Fluorescentes/metabolismo , Dissulfeto de Glutationa/análogos & derivados , Tiorredoxina Dissulfeto Redutase/metabolismo , Tiorredoxinas/metabolismo , Animais , Linhagem Celular Tumoral , Amarelo de Eosina-(YS)/metabolismo , Fluoresceína-5-Isotiocianato/análise , Corantes Fluorescentes/análise , Dissulfeto de Glutationa/metabolismo , Humanos , Insulina/metabolismo , Oxirredução
15.
FASEB J ; 27(4): 1394-403, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23248236

RESUMO

Increasing antibiotic resistance makes the identification of new antibacterial principles an urgent task. The thioredoxin system including thioredoxin reductase (TrxR), thioredoxin (Trx), and NADPH plays critical roles in cellular DNA synthesis and defense against oxidative stress. Notably, TrxR is very different in structure and mechanism in mammals and bacteria. Ebselen [2-phenyl-1,2 benzisoselenazol-3(2H)-one], a well-known antioxidant and a substrate for mammalian TrxR and Trx, is rapidly bacteriocidal for methicillin-resistant Staphylococcus aureus by an unknown mechanism. We have discovered that ebselen is a competitive inhibitor of Escherichia coli TrxR with a Ki of 0.52 ± 0.13 µM, through reaction with the active site dithiol of the enzyme. Bacteria lacking glutathione (GSH) and glutaredoxin, in which TrxR and Trx are essential for DNA synthesis, were particularly sensitive to ebselen. In growth-inhibited E. coli strains, Trx1 and Trx2 were oxidized, demonstrating that electron transfer via thioredoxin was blocked. Ebselen and its sulfur analog ebsulfur were bactericidal for GSH-negative pathogens. Ebsulfur inhibited a clinically isolated Helicobacter pylori strain with a minimum inhibitory concentration value as low as 0.39 µg/ml. These results demonstrate that bacterial Trx and TrxR are viable antibacterial drug targets using benzisoselenazol and benzisothiazol derivates.


Assuntos
Antioxidantes/farmacologia , Azóis/farmacologia , Glutationa/metabolismo , Compostos Organosselênicos/farmacologia , Tiorredoxina Dissulfeto Redutase/metabolismo , Tiorredoxinas/metabolismo , Animais , Células Cultivadas , Escherichia coli , Glutationa/deficiência , Isoindóis , NADP/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores
16.
J Biol Chem ; 287(47): 39686-97, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23012357

RESUMO

Bacillus anthracis is the causative agent of anthrax, which is associated with a high mortality rate. Like several medically important bacteria, B. anthracis lacks glutathione but encodes many genes annotated as thioredoxins, thioredoxin reductases, and glutaredoxin-like proteins. We have cloned, expressed, and characterized three potential thioredoxins, two potential thioredoxin reductases, and three glutaredoxin-like proteins. Of these, thioredoxin 1 (Trx1) and NrdH reduced insulin, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), and the manganese-containing type Ib ribonucleotide reductase (RNR) from B. anthracis in the presence of NADPH and thioredoxin reductase 1 (TR1), whereas thioredoxin 2 (Trx2) could only reduce DTNB. Potential TR2 was verified as an FAD-containing protein reducible by dithiothreitol but not by NAD(P)H. The recently discovered monothiol bacillithiol did not work as a reductant for RNR, either directly or via any of the redoxins. The catalytic efficiency of Trx1 was 3 and 20 times higher than that of Trx2 and NrdH, respectively, as substrates for TR1. Additionally, the catalytic efficiency of Trx1 as an electron donor for RNR was 7-fold higher than that of NrdH. In extracts of B. anthracis, Trx1 was responsible for almost all of the disulfide reductase activity, whereas Western blots showed that the level of Trx1 was 15 and 60 times higher than that of Trx2 and NrdH, respectively. Our findings demonstrate that the most important general disulfide reductase system in B. anthracis is TR1/Trx1 and that Trx1 is the physiologically relevant electron donor for RNR. This information may provide a basis for the development of novel antimicrobial therapies targeting this severe pathogen.


Assuntos
Bacillus anthracis/metabolismo , Proteínas de Bactérias/metabolismo , Ribonucleotídeo Redutases/metabolismo , Tiorredoxina Redutase 1/metabolismo , Tiorredoxinas/metabolismo , Bacillus anthracis/genética , Proteínas de Bactérias/genética , Elétrons , NADP/genética , NADP/metabolismo , Oxirredução , Ribonucleotídeo Redutases/genética , Tiorredoxina Redutase 1/genética , Tiorredoxinas/genética
17.
Br J Cancer ; 104(2): 345-52, 2011 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21179032

RESUMO

BACKGROUND: During the last decade, epidemiological studies uncovered the tremendous impact of metabolic syndrome/diabetes mellitus type 2 (DM T2) as risk factors of the progression of cancer. Therefore, we studied the impact of diabetogenic glucose and insulin concentrations on the activities of tumour cells, because little is known about how high glucose and insulin levels are influencing gene activities causing changes in the signal cascade activities with respect to kinases involved in the proliferation and migration of cancer cells. METHODS: To address this question we analysed the activity of more than 400 gene signatures related to (i) cell cycle, (ii) cell movement as well as (iii) signal transduction. We examined transcriptomes of kinases (PKCα, PI3K), cadherins (E-, N- VE-), integrins and cyclins by comparing physiological (5.5 mM) vs diabetogenic (11 mM) glucose concentrations (without and with insulin). RESULTS: Proliferation assays revealed that high levels of glucose (11 mM) and insulin (100 ng ml(-1)) did promote the proliferation of the tumour cell lines HT29, SW480, MCF-7, MDA MB468, PC3 and T24. Using a 3D-migration assay, we have shown that high glucose concentrations caused increased motility rates of the tumour cells. The increase in migratory activity at high glucose and insulin concentrations was mediated by an activation of PI3K, PKCα and MLCK, as figured out by the pharmacological inhibitors wortmannin, Go6976 and ML-7. CONCLUSION: We present molecular and functional data, which could help to understand how hyperglycaemia and hyperinsulinemia might trigger tumour cell proliferation and motility in patients, too.


Assuntos
Glicemia/metabolismo , Adesão Celular , Movimento Celular , Proliferação de Células , Diabetes Mellitus/metabolismo , Perfilação da Expressão Gênica , Insulina/metabolismo , Western Blotting , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos
18.
BMC Dermatol ; 11: 5, 2011 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-21352568

RESUMO

BACKGROUND: Psoriasis is a chronic inflammatory skin disorder that shows as erythematous and scaly lesions. The pathogenesis of psoriasis is driven by a dysregulation of the immune system which leads to an altered cytokine production. Proinflammatory cytokines that are up-regulated in psoriasis include tumor necrosis factor alpha (TNFα), interleukin-12 (IL-12), and IL-23 for which monoclonal antibodies have already been approved for clinical use. We have previously documented the therapeutic applicability of targeting TNFα mRNA for RNA interference-mediated down-regulation by anti-TNFα small hairpin RNAs (shRNAs) delivered by lentiviral vectors to xenografted psoriatic skin. The present report aims at targeting mRNA encoding the shared p40 subunit (IL-12B) of IL-12 and IL-23 by cellular transduction with lentiviral vectors encoding anti-IL12B shRNAs. METHODS: Effective anti-IL12B shRNAs are identified among a panel of shRNAs by potency measurements in cultured cells. The efficiency and persistency of lentiviral gene delivery to xenografted human skin are investigated by bioluminescence analysis of skin treated with lentiviral vectors encoding the luciferase gene. shRNA-expressing lentiviral vectors are intradermally injected in xenografted psoriatic skin and the effects of the treatment evaluated by clinical psoriasis scoring, by measurements of epidermal thickness, and IL-12B mRNA levels. RESULTS: Potent and persistent transgene expression following a single intradermal injection of lentiviral vectors in xenografted human skin is reported. Stable IL-12B mRNA knockdown and reduced epidermal thickness are achieved three weeks after treatment of xenografted psoriatic skin with lentivirus-encoded anti-IL12B shRNAs. These findings mimic the results obtained with anti-TNFα shRNAs but, in contrast to anti-TNFα treatment, anti-IL12B shRNAs do not ameliorate the psoriatic phenotype as evaluated by semi-quantitative clinical scoring and by immunohistological examination. CONCLUSIONS: Our studies consolidate the properties of lentiviral vectors as a tool for potent gene delivery and for evaluation of mRNA targets for anti-inflammatory therapy. However, in contrast to local anti-TNFα treatment, the therapeutic potential of targeting IL-12B at the RNA level in psoriasis is questioned.


Assuntos
Subunidade p40 da Interleucina-12/antagonistas & inibidores , Psoríase/terapia , RNA Mensageiro/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Animais , Linhagem Celular , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Células HEK293 , Células HeLa , Humanos , Injeções Intradérmicas , Subunidade p40 da Interleucina-12/genética , Lentivirus/genética , Camundongos , Camundongos SCID , Plasmídeos , Psoríase/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Transplante Heterólogo
19.
Front Pharmacol ; 12: 682135, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093206

RESUMO

Antimicrobial resistance in Neisseria gonorrhoeae is threatening the treatment and control of gonorrhea globally, and new treatment options are imperative. Utilizing our dynamic in vitro hollow fiber infection model (HFIM), we examined the pharmacodynamics of the first-in-class spiropyrimidinetrione (DNA gyrase B inhibitors), zoliflodacin, against the N. gonorrhoeae reference strains World Health Organization F (susceptible to all relevant antimicrobials) and WHO X (extensively drug resistant, including resistance to ceftriaxone) over 7 days. Dose-range experiments with both strains, simulating zoliflodacin single oral dose regimens of 0.5-8 g, and dose-fractionation experiments with WHO X, simulating zoliflodacin oral dose therapy with 1-4 g administered as q12 h and q8 h for 24 h, were performed. A kill-rate constant that reflected a rapid bacterial kill during the first 6.5 h for both strains and all zoliflodacin doses was identified. In the dose-range experiments, the zoliflodacin 2-8 g single-dose treatments successfully eradicated both WHO strains, and resistance to zoliflodacin was not observed. However, zoliflodacin as a single 0.5 g dose failed to eradicate both WHO strains, and a 1 g single dose failed to eradicate WHO X in one of two experiments. The zoliflodacin 1 g/day regimen also failed to eradicate WHO X when administered as two and three divided doses given at q12 h and q8 h in the dose-fractionation studies, respectively. All failed regimens selected for zoliflodacin-resistant mutants. In conclusion, these data demonstrate that zoliflodacin should be administered at >2 g as a single oral dose to provide effective killing and resistance suppression of N. gonorrhoeae. Future studies providing pharmacokinetic data for zoliflodacin (and other gonorrhea therapeutic antimicrobials) in urogenital and extragenital infection sites, particularly in the pharynx, and evaluation of gonococcal strains with different gyrB mutations would be important.

20.
G3 (Bethesda) ; 11(5)2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33734373

RESUMO

Hermetia illucens L. (Diptera: Stratiomyidae), the Black Soldier Fly (BSF) is an increasingly important species for bioconversion of organic material into animal feed. We generated a high-quality chromosome-scale genome assembly of the BSF using Pacific Bioscience, 10X Genomics linked read and high-throughput chromosome conformation capture sequencing technology. Scaffolding the final assembly with Hi-C data produced a highly contiguous 1.01 Gb genome with 99.75% of scaffolds assembled into pseudochromosomes representing seven chromosomes with 16.01 Mb contig and 180.46 Mb scaffold N50 values. The highly complete genome obtained a Benchmarking Universal Single-Copy Orthologs (BUSCO) completeness of 98.6%. We masked 67.32% of the genome as repetitive sequences and annotated a total of 16,478 protein-coding genes using the BRAKER2 pipeline. We analyzed an established lab population to investigate the genomic variation and architecture of the BSF revealing six autosomes and an X chromosome. Additionally, we estimated the inbreeding coefficient (1.9%) of the lab population by assessing runs of homozygosity. This provided evidence for inbreeding events including long runs of homozygosity on chromosome 5. The release of this novel chromosome-scale BSF genome assembly will provide an improved resource for further genomic studies, functional characterization of genes of interest and genetic modification of this economically important species.


Assuntos
Cromossomos , Dípteros , Animais , Cromossomos/genética , Dípteros/genética , Genoma , Genômica , Sequências Repetitivas de Ácido Nucleico
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