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1.
J Virol ; 96(24): e0117322, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36448798

RESUMO

White spot syndrome virus (WSSV) is a major cause of disease in shrimp cultures worldwide. The infection process of this large circular double-stranded DNA virus has been well studied, but its entry mechanism remains controversial. The major virion envelope protein VP28 has been implicated in oral and systemic viral infection in shrimp. However, genetic analysis of viral DNA has shown the presence of a few genes related to proteins of per os infectivity factor (PIF) complex in baculoviruses. This complex is essential for the entry of baculoviruses, large terrestrial circular DNA viruses, into the midgut epithelial cells of insect larvae. In this study, we aimed to determine whether a PIF complex exists in WSSV, the components of this complex, whether it functions as an oral infectivity complex in shrimp, and the biochemical properties that contribute to its function in a marine environment. The results revealed a WSSV PIF complex (~720 kDa) comprising at least eight proteins, four of which were not identified as PIF homologs: WSV134, VP124 (WSV216), WSSV021, and WSV136. WSV134 is suggested to be a PIF4 homolog due to predicted structural similarity and amino acid sequence identity. The WSSV PIF complex is resistant to alkali, proteolysis, and high salt, properties that are important for maintaining infectivity in aquatic environments. Oral infection can be neutralized by PIF-specific antibodies but not by VP28-specific antibodies. These results indicate that the WSSV PIF complex is critical for WSSV entry into shrimp; the complex's evolutionary significance is also discussed. IMPORTANCE White spot disease, caused by the white spot syndrome virus (WSSV), is a major scourge in cultured shrimp production facilities worldwide. This disease is only effectively controlled by sanitation. Intervention strategies are urgently needed but are limited by a lack of appropriate targets. Our identification of a per os infectivity factor (PIF) complex, which is pivotal for the entry of WSSV into shrimp, could provide new targets for antibody- or dsRNA-based intervention strategies. In addition, the presence of a PIF complex with at least eight components in WSSV, which is ancestrally related to the PIF complex of invertebrate baculoviruses, suggests that this complex is structurally and functionally conserved in disparate virus taxa.


Assuntos
Penaeidae , Fatores de Virulência , Vírus da Síndrome da Mancha Branca 1 , Animais , Vírus da Síndrome da Mancha Branca 1/genética , Vírus da Síndrome da Mancha Branca 1/patogenicidade , Fatores de Virulência/genética , Internalização do Vírus
2.
Eur J Neurosci ; 55(5): 1356-1372, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35080077

RESUMO

Amyotrophic lateral sclerosis (ALS) is a lethal and incurable neurodegenerative disease due to the loss of upper and lower motor neurons, which leads to muscle weakness, atrophy, and paralysis. Sigma-1 receptor (σ-1R) is a ligand-operated protein that exhibits pro-survival and anti-apoptotic properties. In addition, mutations in its codifying gene are linked to development of juvenile ALS pointing to an important role in ALS. Here, we investigated the disease-modifying effects of pridopidine, a σ-1R agonist, using a delayed onset SOD1 G93A mouse model of ALS. Mice were administered a continuous release of pridopidine (3.0 mg/kg/day) for 4 weeks starting before the appearance of any sign of muscle weakness. Mice were monitored weekly and several behavioural tests were used to evaluate muscle strength, motor coordination and gait patterns. Pridopidine-treated SOD1 G93A mice showed genotype-specific effects with the prevention of cachexia. In addition, these effects exhibited significant improvement of motor behaviour 5 weeks after treatment ended. However, the survival of the animals was not extended. In summary, these results show that pridopidine can modify the disease phenotype of ALS-associated cachexia and motor deficits in a SOD1 G93A mouse model.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Esclerose Lateral Amiotrófica/genética , Animais , Caquexia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Debilidade Muscular , Fenótipo , Piperidinas , Superóxido Dismutase/genética , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
3.
BMC Med ; 20(1): 359, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36266654

RESUMO

BACKGROUND: The severe fever with thrombocytopenia syndrome disease (SFTS), caused by the novel tick-borne SFTS virus (SFTSV), was listed among the top 10 priority infectious disease by World Health Organization due to the high fatality rate of 5-30% and the lack of effective antiviral drugs and vaccines and therefore raised the urgent need to develop effective anti-SFTSV drugs to improve disease treatment. METHODS: The antiviral drugs to inhibit SFTSV infection were identified by screening the library containing 1340 FDA-approved drugs using the SFTSV infection assays in vitro. The inhibitory effect on virus entry and the process of clathrin-mediated endocytosis under different drug doses was evaluated based on infection assays by qRT-PCR to determine intracellular viral copies, by Western blot to characterize viral protein expression in cells, and by immunofluorescence assays (IFAs) to determine virus infection efficiencies. The therapeutic effect was investigated in type I interferon receptor defective A129 mice in vivo with SFTSV infection, from which lesions and infection in tissues caused by SFTSV infection were assessed by H&E staining and immunohistochemical analysis. RESULTS: Six drugs were identified as exerting inhibitory effects against SFTSV infection, of which anidulafungin, an antifungal drug of the echinocandin family, has a strong inhibitory effect on SFTSV entry. It suppresses SFTSV internalization by impairing the late endosome maturation and decreasing virus fusion with the membrane. SFTSV-infected A129 mice had relieving symptoms, reduced tissue lesions, and improved disease outcomes following anidulafungin treatment. Moreover, anidulafungin exerts an antiviral effect in inhibiting the entry of other viruses including SARS-CoV-2, SFTSV-related Guertu virus and Heartland virus, Crimean-Congo hemorrhagic fever virus, Zika virus, and Herpes simplex virus 1. CONCLUSIONS: The results demonstrated that the antifungal drug, anidulafungin, could effectively inhibit virus infection by interfering with virus entry, suggesting it may be utilized for the clinical treatment of infectious viral diseases, in addition to its FDA-approved use as an antifungal. The findings also suggested to further evaluate the anti-viral effects of echinocandins and their clinical importance for patients with infection of viruses, which may promote therapeutic strategies as well as treatments and improve outcomes pertaining to various viral and fungal diseases.


Assuntos
Anidulafungina , Infecções por Bunyaviridae , Viroses , Animais , Camundongos , Anidulafungina/farmacologia , Anidulafungina/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Bunyaviridae/tratamento farmacológico , Clatrina , Receptor de Interferon alfa e beta , SARS-CoV-2 , Proteínas Virais , Viroses/tratamento farmacológico
4.
Angew Chem Int Ed Engl ; 61(20): e202200164, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35238122

RESUMO

Herein, an Ir-catalyzed asymmetric allylic substitution reaction of methyl azaarenes is described. Azaarenes such as (benzo)thiazole, oxazole, benzoimidazole, pyridine, and (iso)quinoline are all tolerated. The corresponding chiral azaarene derivatives are obtained in good yields with high enantioselectivity (up to 96 % yield and 99 % ee). The utilization of the Knochel reagent TMPZnBr⋅LiBr warrants the in situ formation of benzylic nucleophiles without additional activating reagents. 1 H NMR studies suggested a two-fold function of the Knochel reagent in this reaction. The synthetic utility of this method has been showcased by a concise enantioselective synthesis of an allosteric protein kinase modulator.


Assuntos
Irídio , Catálise , Irídio/química , Estereoisomerismo
5.
J Virol ; 93(6)2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30602603

RESUMO

Baculovirus entry into insect midgut cells is dependent on a multiprotein complex of per os infectivity factors (PIFs) on the envelopes of occlusion-derived virions (ODVs). The structure and assembly of the PIF complex are largely unknown. To reveal the complete members of the complex, a combination of blue native polyacrylamide gel electrophoresis, liquid chromatography-tandem mass spectrometry, and Western blotting was conducted on three different baculoviruses. The results showed that the PIF complex has a molecular mass of ∼500 kDa and consists of nine PIFs, including a newly discovered member (PIF9). To decipher the assembly process, each pif gene was knocked out from the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) genome individually by use of synthetic baculovirus technology, and the impact on PIF complex formation was investigated. Deletion of pif8 resulted in the formation of an ∼400-kDa subcomplex. Deletion of pif0, -4, -6, -7, or -9 resulted in a subcomplex of ∼230 kDa, but deletion of pif1, -2, or -3 abolished formation of any complex. Taken together, our data identified a core complex of ∼230 kDa, consisting of PIF1, -2, and -3. This revised the previous knowledge that the core complex was about 170 kDa and contained PIF1 to -4. Analysis of the PIF complex in cellular fractions suggested that it is assembled in the cytoplasm before being transported to the nucleus and subsequently incorporated into the envelopes of ODVs. Only the full complex, not the subcomplex, is resistant to proteolytic attack, indicating the essentiality of correct complex assembly for oral infection.IMPORTANCE Entry of baculovirus into host insects is mediated by a per os infectivity factor (PIF) complex on the envelopes of occlusion-derived viruses (ODVs). Knowledge of the composition and structure of the PIF complex is fundamental to understanding its mode of action. By using multiple approaches, we determined the complete list of proteins (nine) in the PIF complex. In contrast to previous knowledge in the field, the core complex is revised to ∼230 kDa and consists of PIF1 to -3 but not PIF4. Interestingly, our results suggest that the PIF complex is formed in the cytoplasm prior to its transport to the nucleus and subsequent incorporation into ODVs. Only the full complex is resistant to proteolytic degradation in the insect midgut, implying the critical role of the entire complex. These findings provide the baseline for future studies on the ODV entry mechanism mediated by the multiprotein complex.


Assuntos
Baculoviridae/metabolismo , Baculoviridae/patogenicidade , Fatores de Virulência/metabolismo , Animais , Linhagem Celular , Infecções por Vírus de DNA , Insetos/virologia , Nucleopoliedrovírus/patogenicidade , Células Sf9 , Proteínas do Envelope Viral/metabolismo , Vírion/patogenicidade
6.
J Transl Med ; 18(1): 435, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33187526

RESUMO

BACKGROUND: Metastasized clear cell renal cell carcinoma (ccRCC) is associated with a poor prognosis. Almost one-third of patients with non-metastatic tumors at diagnosis will later progress with metastatic disease. These patients need to be identified already at diagnosis, to undertake closer follow up and/or adjuvant treatment. Today, clinicopathological variables are used to risk classify patients, but molecular biomarkers are needed to improve risk classification to identify the high-risk patients which will benefit most from modern adjuvant therapies. Interestingly, DNA methylation profiling has emerged as a promising prognostic biomarker in ccRCC. This study aimed to derive a model for prediction of tumor progression after nephrectomy in non-metastatic ccRCC by combining DNA methylation profiling with clinicopathological variables. METHODS: A novel cluster analysis approach (Directed Cluster Analysis) was used to identify molecular biomarkers from genome-wide methylation array data. These novel DNA methylation biomarkers, together with previously identified CpG-site biomarkers and clinicopathological variables, were used to derive predictive classifiers for tumor progression. RESULTS: The "triple classifier" which included both novel and previously identified DNA methylation biomarkers together with clinicopathological variables predicted tumor progression more accurately than the currently used Mayo scoring system, by increasing the specificity from 50% in Mayo to 64% in our triple classifier at 85% fixed sensitivity. The cumulative incidence of progress (pCIP5yr) was 7.5% in low-risk vs 44.7% in high-risk in M0 patients classified by the triple classifier at diagnosis. CONCLUSIONS: The triple classifier panel that combines clinicopathological variables with genome-wide methylation data has the potential to improve specificity in prognosis prediction for patients with non-metastatic ccRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/genética , Metilação de DNA/genética , Epigênese Genética , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Prognóstico
7.
Angew Chem Int Ed Engl ; 59(5): 2039-2043, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31693789

RESUMO

The stereodivergent iridium-catalyzed allylic alkylation and fluorination of acyclic ketones is described. α-Pyridyl-α-fluoroketones with vicinal tertiary and quaternary stereocenters were obtained in moderate to excellent yields and stereoselectivities. Distinct from known stereodivergent synthesis, for which two different chiral catalysts are required in general, herein we report a sequence-dependent stereodivergent synthesis. With only a single chiral Ir catalyst, all four possible stereoisomers of the products were prepared from the same starting materials by simply adjusting the sequence of asymmetric allylic alkylation and fluorination and varying the absolute configuration of the Ir catalyst.

8.
Angew Chem Int Ed Engl ; 58(31): 10493-10499, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31081989

RESUMO

Described herein is an asymmetric allylic aromatization (AAAr) strategy that employs readily accessible equivalents of benzylic nucleophiles in iridium-catalyzed allylic substitution reactions with the concomitant formation of aromatic rings by aromatization. The optimized reaction conditions involving a catalyst derived from a commercially available iridium precursor and the Carreira ligand are compatible with equivalents of benzylic nucleophiles derived from 4- or 5-methyloxazoles, 5-methylthiazoles, 4- or 5-methylfurans, 2- or 3-methylbenzofurans, 3-methylbenzothiophene, 3-methylindole, 1-methylnaphthalene, and methylbenzene. This strategy provides straightforward accesses to valuable heterocyclic aromatic compounds, bearing a homobenzylic stereogenic center, in an enantiopure form and would be difficult to access otherwise. The versatility of the reaction was showcased by the further elaboration of the products into useful building blocks and a drug analogue.

9.
Breast Cancer Res ; 20(1): 153, 2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30558679

RESUMO

BACKGROUND: Overdiagnosis, defined as the detection of a cancer that would not become clinically apparent in a woman's lifetime without screening, has become a growing concern. Similar underlying risk of breast cancer in the screened and control groups is a prerequisite for unbiased estimates of overdiagnosis, but a contemporary control group is usually not available in organized screening programs. METHODS: We estimated the frequency of overdiagnosis of breast cancer due to screening in women 50-69 years old by using individual screening data from the population-based organized screening program in Stockholm County 1989-2014. A hidden Markov model with four latent states and three observed states was constructed to estimate the natural progression of breast cancer and the test sensitivity. Piecewise transition rates were used to consider the time-varying transition rates. The expected number of detected non-progressive breast cancer cases was calculated. RESULTS: During the study period, 2,333,153 invitations were sent out; on average, the participation rate in the screening program was 72.7% and the average recall rate was 2.48%. In total, 14,648 invasive breast cancer cases were diagnosed; among the 8305 screen-detected cases, the expected number of non-progressive breast cancer cases was 35.9, which is equivalent to 0.43% (95% confidence interval (CI) 0.10%-2.2%) overdiagnosis. The corresponding estimates for the prevalent and subsequent rounds were 15.6 (0.87%, 95% CI 0.20%-4.3%) and 20.3 (0.31%, 95% CI 0.07%-1.6%), respectively. The likelihood ratio test showed that the non-homogeneous model fitted the data better than an age-homogeneous model (P <0.001). CONCLUSIONS: Our findings suggest that overdiagnosis in the organized biennial mammographic screening for women 50-69 in Stockholm County is a minor phenomenon. The frequency of overdiagnosis in the prevalent screening round was higher than that in subsequent rounds. The non-homogeneous model performed better than the simpler, traditional homogeneous model.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricos , Uso Excessivo dos Serviços de Saúde/estatística & dados numéricos , Idoso , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer/métodos , Feminino , Seguimentos , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Prevalência , Suécia/epidemiologia
10.
Angew Chem Int Ed Engl ; 56(14): 4002-4005, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28266102

RESUMO

An enantioselective iridium-catalyzed allylic substitution with a set of highly unstabilized nucleophiles generated in situ from 2-methylpyridines is described. Enantioenriched 2-substituted pyridines, which are frequently encountered in natural products and pharmaceuticals, could be easily constructed by this simple method in good yields and excellent enantioselectivity. The synthetic utility of the pyridine products is demonstrated through the synthesis of a key intermediate of a reported Na+ /H+ exchanger inhibitor and the total synthesis of (-)-lycopladine A.

11.
Angew Chem Int Ed Engl ; 56(12): 3237-3241, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28067451

RESUMO

An Ir-catalyzed intermolecular asymmetric dearomatization reaction of ß-naphthols with allyl alcohols or allyl ethers was developed. When an iridium catalyst generated from [Ir(COD)Cl]2 (COD=cyclooctadiene) and a chiral P/olefin ligand is employed, highly functionalized ß-naphthalenone compounds bearing an all-carbon-substituted quaternary chiral center were obtained in up to 92 % yield and 98 % ee. The direct utilization of allyl alcohols as electrophiles represents an improvement from the viewpoint of atom economy. Allyl ethers were found to undergo asymmetric allylic substitution reaction under Ir catalysis for the first time. The diverse transformations of the dearomatized product to various motifs render this method attractive.

12.
Angew Chem Int Ed Engl ; 56(26): 7440-7443, 2017 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-28466512

RESUMO

A highly efficient synthesis of the enantioenriched tetrahydro-ß-carbolines was developed by using a chiral phosphoric acid catalyzed Pictet-Spengler reaction of indolyl dihydropyridines. The reaction proceeds under mild reaction conditions to afford the desired chiral tetrahydro-ß-carbolines in good to excellent yields (up to 96 %) and high enantioselectivities (up to 99 % ee). With this method, a formal synthesis of tangutorine and a total synthesis of deplancheine were achieved in a highly efficient manner.

13.
Infect Immun ; 83(8): 3233-42, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26034213

RESUMO

Certain intracellular bacteria use the host cell cytosol as the replicative niche. Although it has been hypothesized that the successful exploitation of this compartment requires a unique metabolic adaptation, supportive evidence is lacking. For Francisella tularensis, many genes of the Francisella pathogenicity island (FPI) are essential for intracellular growth, and therefore, FPI mutants are useful tools for understanding the prerequisites of intracytosolic replication. We compared the growth of bacteria taken up by phagocytic or nonphagocytic cells with that of bacteria microinjected directly into the host cytosol, using the live vaccine strain (LVS) of F. tularensis; five selected FPI mutants thereof, i.e., ΔiglA, ΔiglÇ ΔiglG, ΔiglI, and ΔpdpE strains; and Listeria monocytogenes. After uptake in bone marrow-derived macrophages (BMDM), ASC(-/-) BMDM, MyD88(-/-) BMDM, J774 cells, or HeLa cells, LVS, ΔpdpE and ΔiglG mutants, and L. monocytogenes replicated efficiently in all five cell types, whereas the ΔiglA and ΔiglC mutants showed no replication. After microinjection, all 7 strains showed effective replication in J774 macrophages, ASC(-/-) BMDM, and HeLa cells. In contrast to the rapid replication in other cell types, L. monocytogenes showed no replication in MyD88(-/-) BMDM and LVS showed no replication in either BMDM or MyD88(-/-) BMDM after microinjection. Our data suggest that the mechanisms of bacterial uptake as well as the permissiveness of the cytosolic compartment per se are important factors for the intracytosolic replication. Notably, none of the investigated FPI proteins was found to be essential for intracytosolic replication after microinjection.


Assuntos
Replicação do DNA , Francisella tularensis/crescimento & desenvolvimento , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/microbiologia , Tularemia/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Citosol/metabolismo , Citosol/microbiologia , Francisella tularensis/genética , Francisella tularensis/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Listeria monocytogenes/genética , Listeria monocytogenes/metabolismo , Listeriose/genética , Listeriose/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Microinjeções , Tularemia/genética , Tularemia/metabolismo
14.
Angew Chem Int Ed Engl ; 54(49): 14929-32, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26463712

RESUMO

An intermolecular asymmetric dearomatization reaction of ß-naphthols with nitroethylene through a chiral-thiourea-catalyzed Michael reaction is described. Enantioenriched functionalized ß-naphthalenones with an all-carbon quaternary stereogenic center could thus be easily constructed from simple naphthol derivatives in good yields and excellent enantioselectivity (up to 79% yield, 98% ee).

15.
J Virol ; 87(2): 829-39, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23115289

RESUMO

The replication of lepidopteran baculoviruses is characterized by the production of two progeny phenotypes: the occlusion-derived virus (ODV), which establishes infection in midgut cells, and the budded virus (BV), which disseminates infection to different tissues within a susceptible host. To understand the structural, and hence functional, differences between BV and ODV, we employed multiple proteomic methods to reveal the protein compositions and posttranslational modifications of the two phenotypes of Helicoverpa armigera nucleopolyhedrovirus. In addition, Western blotting and quantitative mass spectrometry were used to identify the localization of proteins in the envelope or nucleocapsid fractions. Comparative protein portfolios of BV and ODV showing the distribution of 54 proteins, encompassing the 21 proteins shared by BV and ODV, the 12 BV-specific proteins, and the 21 ODV-specific proteins, were obtained. Among the 11 ODV-specific envelope proteins, 8 either are essential for or contribute to oral infection. Twenty-three phosphorylated and 6 N-glycosylated viral proteins were also identified. While the proteins that are shared by the two phenotypes appear to be important for nucleocapsid assembly and trafficking, the structural and functional differences between the two phenotypes are evidently characterized by the envelope proteins and posttranslational modifications. This comparative proteomics study provides new insight into how BV and ODV are formed and why they function differently.


Assuntos
Baculoviridae/química , Lepidópteros/virologia , Proteoma/análise , Proteínas Virais/análise , Animais , Western Blotting , Linhagem Celular , Espectrometria de Massas , Fenótipo , Processamento de Proteína Pós-Traducional
16.
Front Cell Infect Microbiol ; 14: 1381776, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628552

RESUMO

Introduction: For a majority of tularemia patients, serology is the basis for the diagnosis. The aim of this study was to perform an analysis of the samples analyzed at a Swedish reference laboratory for the presence of Francisella tularensis-specific antibody levels in sera from individuals with suspected tularemia. Annual and monthly variations of the total number of samples and proportions of positive samples were analyzed, as well as the influence of age and gender. Methods: We performed a retrospective analysis of the presence of F. tularensis-specific antibodies in serological samples from patients with suspected tularemia analyzed during the period 2010 - 2022 at the University Hospital of Umeå in Sweden, a national reference laboratory, by use of various statistical methods. In total, some 15,100 serum samples had been analyzed for the presence of IgG and IgM antibodies by ELISA during the 13-year period. Results: Overall, there were higher number of samples with IgG positive or borderline titers, 2,522 and 921, respectively, than with IgM positive or borderline titers, 1,802 and 409, respectively. Repeated samples were obtained from some 1,930 individuals and approximately a third of the cases, which were initially seronegative, had seroconverted when resampled. Peak number of monthly samples were recorded in August and September, > 3,000. Annual numbers varied greatly and peak numbers were observed in 2015 and 2019, 1,832 and 2,250, respectively, whereas some other years the numbers were 700 - 800. There was also much variation in the annual and monthly percentages of positive samples and they varied between less than 10% to greater than 20%. The highest percentages of positive samples were recorded in September and October. IgG and IgM titers declined with age and these differences were highly significant for IgG titers, with decreasing average titers for each 20-year interval. Discussion: Collectively, the data demonstrate the marked annual and seasonal variations in tularemia sampling occurring in Sweden. Also, the proportion of positive samples increased during months and years with peak number of samples. Another notable finding was that average antibody titers decreased with increased age.


Assuntos
Francisella tularensis , Tularemia , Humanos , Tularemia/diagnóstico , Tularemia/epidemiologia , Suécia/epidemiologia , Estudos Retrospectivos , Anticorpos Antibacterianos , Imunoglobulina M , Imunoglobulina G
17.
Front Cell Infect Microbiol ; 13: 1192038, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465761

RESUMO

Interpretation of serological findings in suspected Lyme borreliosis (LB) is challenging and IgM reactivities may have low predictive value. Therefore, if used indiscriminately, there is a risk for incorrect diagnosis of LB. To evaluate the usefulness of IgM titer determination, we performed a study of the prevalence of Borrelia-specific antibodies in serological samples from patients with suspected LB analyzed during the period 2010 - 2021 at the University Hospital of Umeå in Sweden. In total, 19,335 samples had been analyzed for the presence of IgG and IgM antibodies. Overall, there were higher percentages of IgM positive or borderline titers, 1,847 (9.6%) and 905 (4.7%), respectively, than IgG positive or borderline titers, 959 (5.0%) and 406 (2.1%), respectively. Peak number of samples were recorded 2012 - 2013, exceeding 1,800, whereas there were around 1,200 during 2020 - 2021. The peak number of positive IgG and/or positive IgM samples were observed during the period 2015 - 2017 with close to, or above 400, and concomitantly, the proportion of IgG positive samples increased markedly. For IgG positive samples, the increase followed a positive linear time trend (P< 0.001). Peak monthly numbers were observed during August, September, and October. This seasonal increase was significant for the IgG positive group (P< 0.05), but not for the IgM positive/IgG negative group. Repeated samples were obtained from 3,188 individuals and of the initial samples 2,817 were (88%) IgG negative and 2,315 (72%) were IgM negative and of these, 130 (4%) showed IgG seroconversion and 300 (9%) IgM seroconversion. Collectively, the data demonstrate that IgG and/or IgM positive samples represented a minority of all samples, even when repeated sampling had occurred, and IgM positive samples were much more common than IgG positive samples. Thus, the accuracy of the clinical suspicion was low and this will lead to a low predictive value of the analysis, in particular of IgM. These findings question the use of IgM titer determination as a routine analysis.


Assuntos
Anticorpos Antibacterianos , Borrelia , Imunoglobulina G , Imunoglobulina M , Doença de Lyme , Humanos , Anticorpos Antibacterianos/sangue , Borrelia/imunologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Doença de Lyme/diagnóstico , Suécia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Estações do Ano , Testes Diagnósticos de Rotina/normas , Reprodutibilidade dos Testes , Valor Preditivo dos Testes
18.
Epigenetics ; 18(1): 2196759, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36994855

RESUMO

Endogenous sex hormones and DNA methylation both play important roles in various diseases. However, their interplay is largely unknown. A deeper understanding of their interrelationships could provide new insights into the pathology of disease development. We, therefore, investigated associations between circulating sex hormones, sex hormone binding globulin (SHBG), and DNA methylation in blood, using samples from 77 men (65 with repeated samples), from the population-based Northern Sweden Health and Disease Study (NSHDS). DNA methylation was measured in buffy coat using the Infinium Methylation EPIC BeadChip (Illumina). Sex hormone (oestradiol, oestrone, testosterone, androstenedione, dehydroepiandrosterone, and progesterone) and SHBG concentrations were measured in plasma using a high-performance liquid chromatography tandem mass spectrometry (LC/MS-MS) method and an enzyme-linked immunoassay, respectively. Associations between sex hormones, SHBG, and DNA methylation were estimated using both linear regression and mixed-effects models. Additionally, we used the comb-p method to identify differentially methylated regions based on nearby P values. We identified one novel CpG site (cg14319657), at which DNA methylation was associated with dehydroepiandrosterone, surpassing a genome-wide significance level. In addition, more than 40 differentially methylated regions were associated with levels of sex hormones and SHBG and several of these mapped to genes involved in hormone-related diseases. Our findings support a relationship between circulating sex hormones and DNA methylation and suggest that further investigation is warranted, both for validation, further exploration and to gain a deeper understanding of the mechanisms and potential consequences for health and disease.


Assuntos
Metilação de DNA , Epigenoma , Masculino , Humanos , Hormônios Esteroides Gonadais/genética , Estradiol , Desidroepiandrosterona
19.
Insect Biochem Mol Biol ; 147: 103775, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35504546

RESUMO

Melanization is a key immune response mediated by serine protease (SP) cascade in insects. Multiple SP pathways exist in different species and it is unclear how conserved these cascades are. The cotton bollworm Helicoverpa armigera is a major worldwide agricultural pest. We reported a conserved melanization pathway in this species, which consists of SP41, cSP1, and cSP6. In this study, we attempted to identify an insect pathogen that elicits the cascade and test whether or not there are other SP cascades in H. armigera. After Micrococcus luteus, Enterobacter cloacae, Beauveria bassiana, or Helicoverpa armigera nucleopolyhedrovirus were injected into larvae, pathogen-induced hemolymph samples were collected for in vitro biochemical assays, which failed to detect proSP41 or procSP1 activation. In contrast, we found that procSP4, a protein proposed to participate in H. armigera melanization, was activated in M. luteus infected hemolymph. We further revealed that cSP8 was a prophenoloxidase (PPO) activating protease downstream of cSP4, and cSP4 was activated by cSP10. The pathway of cSP10-cSP4-cSP8 activated PPO in vitro. Efficiently cleaved procSPH11 and procSPH50 by cSP8 substantially enhanced phenoloxidase activity, suggesting they work together as a cofactor for cSP8 mediated PPO activation. Hemolymph from larvae challenged with M. luteus or its peptidoglycan effectively activated procSP10. Collectively, these results revealed a new PPO activation cascade specifically triggered by the bacterium. In addition, we found that the PPO activation cascades in H. armigera and Manduca sexta are conserved.


Assuntos
Micrococcus luteus , Mariposas , Animais , Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Hemolinfa/metabolismo , Proteínas de Insetos/metabolismo , Larva/metabolismo , Micrococcus luteus/metabolismo , Mariposas/metabolismo , Serina Endopeptidases , Serina Proteases/metabolismo
20.
Cancer Epidemiol Biomarkers Prev ; 31(4): 793-803, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35086823

RESUMO

BACKGROUND: Endogenous sex hormones may contribute to higher colorectal cancer incidence rates in men compared with women, but despite an increased number of studies, clear evidence is lacking. METHODS: We conducted a comprehensive nested case-control study of circulating concentrations of sex hormones, sex hormone precursors, and sex hormone binding globulin (SHBG) in relation to subsequent colon cancer risk in European men. Concentrations were measured using liquid LC/MS-MS in prospectively collected plasma samples from 690 cases and 690 matched controls from the European Prospective Investigation into Cancer and Nutrition (EPIC) and the Northern Sweden Health and Disease Study (NSHDS) cohorts. Multivariable conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). In addition, we conducted a meta-analysis of previous studies on men. RESULTS: Circulating levels of testosterone (OR, 0.68; 95% CI, 0.51-0.89) and SHBG (OR, 0.77; 95% CI, 0.62-0.96) were inversely associated with colon cancer risk. For free testosterone, there was a nonsignificant inverse association (OR, 0.83; 95% CI, 0.58-1.18). In a dose-response meta-analysis of endogenous sex hormone levels, inverse associations with colorectal/colon cancer risk were found for testosterone [relative risks (RR) per 100 ng/dL = 0.98; 95% CI, 0.96-1.00; I2 = 22%] and free testosterone (RR per 1 ng/dL = 0.98; 95% CI, 0.95-1.00; I2 = 0%). CONCLUSIONS: Our results provide suggestive evidence for the association between testosterone, SHBG, and male colon cancer development. IMPACT: Additional support for the involvement of sex hormones in male colon cancer.


Assuntos
Neoplasias do Colo , Globulina de Ligação a Hormônio Sexual , Estudos de Casos e Controles , Neoplasias do Colo/epidemiologia , Estradiol , Feminino , Hormônios Esteroides Gonadais , Humanos , Modelos Logísticos , Masculino , Estudos Prospectivos , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona
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