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1.
JAMA Netw Open ; 7(3): e242375, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38526495

RESUMO

Importance: There is a lack of trials examining the effect of counseling interventions for child, adolescent, and younger adult (CAYA) cancer survivors. Objective: To assess lifestyle habits and the psychosocial situation of CAYAs to determine the efficacy of needs-based interventions in the CARE for CAYA program (CFC-P). Design, Setting, and Participants: The CFC-P was conducted as a multicenter program in 14 German outpatient clinics, mainly university cancer centers. Recruitment began January 1, 2018; a randomized clinical trial was conducted until July 15, 2019; and intervention was continued as a longitudinal cohort study until March 31, 2021. Data preparation was conducted from April 1, 2021, and analysis was conducted from August 14, 2021, to May 31, 2022. Herein, predefined confirmatory analyses pertain to the RCT and descriptive results relate to the overall longitudinal study. Data analysis was based on the full analysis set, which is as close as possible to the intention-to-treat principle. Intervention: A comprehensive assessment determined needs in physical activity, nutrition and psychooncology. Those with high needs participated in 1 to 3 modules. In the RCT, the IG received 5 counseling sessions plus newsletters, while the control group CG received 1 counseling session. Main Outcomes and Measures: The primary outcome was the change in the rate of CAYAs with high needs at 52 weeks. Secondary outcomes were feasibility, modular-specific end points, satisfaction, quality of life, and fatigue. Results: Of 1502 approached CAYAs aged 15 to 39 years, 692 declined participation. Another 22 CAYAs were excluded, resulting in 788 participants. In the randomized clinical trial, 359 CAYAs were randomized (intervention group [IG], n = 183; control group [CG], n = 176), and 274 were followed up. In the RCT, the median age was 25.0 (IQR, 19.9-32.2) years; 226 were female (63.0%) and 133 male (37.0%). After 52 weeks, 120 CAYAs (87.0%) in the IG and 115 (86.5%) in the CG still had a high need in at least 1 module (odds ratio, 1.04; 95% CI, 0.51-2.11; P = .91). Both groups reported reduced needs, improved quality of life, reduced fatigue, and high satisfaction with the CFC-P. Conclusions and Relevance: In this randomized clinical trial, the implementation of a lifestyle program in this cohort was deemed necessary, despite not meeting the primary outcome. The interventions did not alter the rate of high needs. The results may provide guidance for the development of multimodal interventions in the follow-up care of CAYAs. Trial Registration: German Clinical Trial Register: DRKS00012504.


Assuntos
Sobreviventes de Câncer , Neoplasias , Adolescente , Adulto , Criança , Feminino , Masculino , Humanos , Estudos Longitudinais , Sobrevivência , Qualidade de Vida , Estudos de Coortes , Estilo de Vida , Fadiga , Neoplasias/terapia
2.
Cancers (Basel) ; 15(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37760564

RESUMO

Cancer often causes long-term physical and psychological impairments. Lifestyle modification and nature-based interventions (NBIs) can have a positive impact on patients' quality of life (QOL). This participants-blinded, non-randomized controlled study assessed parameters at weeks 0, 12, and 24, including, as a primary endpoint, QOL in cancer patients on the Functional Assessment of Cancer Therapy-General (FACT-G) at week 12. QOL in breast cancer patients, fatigue, well-being, stress, anxiety/depression, socio-psychological well-being, benefits of nature interaction, insomnia, self-efficacy, mindfulness, and self-compassion were assessed as secondary endpoints. N = 107 cancer patients (96.3% women; 52.5 ± 9.3 years, 80.4% breast cancer) were assigned to either a 12-week nature-based (NDC; n = 56) or conventional (DC; n = 51) oncology day care clinic program, whereby the assignment group was not known to the participants. There was no significant group difference for the primary endpoint. At week 24, QOL, fatigue, mindfulness and self-compassion scores were significantly higher, and at weeks 12 and 24, the insomnia score was significantly lower in NDC compared to DC. In conclusion, this study indicates positive and clinically relevant effects of the program on QOL, fatigue, and psychological parameters. NBIs seem to have a more pronounced effect.

3.
Appl Microbiol Biotechnol ; 107(13): 4337-4353, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37204448

RESUMO

Brevibacillus laterosporus (Bl) is a Gram-positive and spore-forming bacterium. Insect pathogenic strains have been characterised in New Zealand, and two isolates, Bl 1821L and Bl 1951, are under development for use in biopesticides. However, growth in culture is sometimes disrupted, affecting mass production. Based on previous work, it was hypothesised that Tectiviridae phages might be implicated. While investigating the cause of the disrupted growth, electron micrographs of crude lysates showed structural components of putative phages including capsid and tail-like structures. Sucrose density gradient purification yielded a putative self-killing protein of ~30 kDa. N-terminal sequencing of the ~30 kDa protein identified matches to a predicted 25 kDa hypothetical and a 31.4 kDa putative encapsulating protein homologs, with the genes encoding each protein adjacent in the genomes. BLASTp analysis of the homologs of 31.4 kDa amino acid sequences shared 98.6% amino acid identity to the Linocin M18 bacteriocin family protein of Brevibacterium sp. JNUCC-42. Bioinformatic tools including AMPA and CellPPD defined that the bactericidal potential originated from a putative encapsulating protein. Antagonistic activity of the ~30 kDa encapsulating protein of Bl 1821L and Bl 1951during growth in broth exhibited bacterial autolytic activity. LIVE/DEAD staining of Bl 1821L cells after treatment with the ~30 kDa encapsulating protein of Bl 1821L substantiated the findings by showing 58.8% cells with the compromised cell membranes as compared to 37.5% cells in the control. Furthermore, antibacterial activity of the identified proteins of Bl 1821L was validated through gene expression in a Gram-positive bacterium Bacillus subtilis WB800N. KEY POINTS: • Gene encoding the 31.4 kDa antibacterial Linocin M18 protein was identified • It defined the autocidal activity of Linocin M18 (encapsulating) protein • Identified the possible killing mechanism of the encapsulins.


Assuntos
Bacillus , Bacteriocinas , Brevibacillus , Animais , Brevibacillus/genética , Brevibacillus/metabolismo , Antibacterianos/metabolismo , Insetos
4.
PLoS Pathog ; 19(4): e1011338, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37075064

RESUMO

Fungal pathogens overcome antifungal drug therapy by classic resistance mechanisms, such as increased efflux or changes to the drug target. However, even when a fungal strain is susceptible, trailing or persistent microbial growth in the presence of an antifungal drug can contribute to therapeutic failure. This trailing growth is caused by adaptive physiological changes that enable the growth of a subpopulation of fungal cells in high drug concentrations, in what is described as drug tolerance. Mechanistically, antifungal drug tolerance is incompletely understood. Here we report that the transcriptional activator Rpn4 is important for drug tolerance in the human fungal pathogen Candida albicans. Deletion of RPN4 eliminates tolerance to the commonly used antifungal drug fluconazole. We defined the mechanism and show that Rpn4 controls fluconazole tolerance via two target pathways. First, Rpn4 activates proteasome gene expression, which enables sufficient proteasome capacity to overcome fluconazole-induced proteotoxicity and the accumulation of ubiquitinated proteins targeted for degradation. Consistently, inhibition of the proteasome with MG132 eliminates fluconazole tolerance and resistance, and phenocopies the rpn4Δ/Δ mutant for loss of tolerance. Second, Rpn4 is required for wild type expression of the genes required for the synthesis of the membrane lipid ergosterol. Our data indicates that this function of Rpn4 is required for mitigating the inhibition of ergosterol biosynthesis by fluconazole. Based on our findings, we propose that Rpn4 is a central hub for fluconazole tolerance in C. albicans by coupling the regulation of protein homeostasis (proteostasis) and lipid metabolism to overcome drug-induced proteotoxicity and membrane stress.


Assuntos
Antifúngicos , Complexo de Endopeptidases do Proteassoma , Humanos , Antifúngicos/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteostase , Fluconazol , Candida albicans/metabolismo , Tolerância a Medicamentos , Ergosterol , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana
5.
Biomarkers ; 28(1): 97-110, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36377411

RESUMO

INTRODUCTION: Patients with cardiovascular disease (CVD) and acute SARS-CoV-2 infection might show an altered immune response during COVID-19. MATERIAL AND METHODS: Twenty-three patients with CVD and SARS-CoV-2 infection were prospectively enrolled and received a cardiological assessment at study entry and during follow-up visit. Inclusion criteria of our study were age older than 18 years, presence of CVD, and acute SARS-CoV-2 infection. The median age of the patient cohort was 69 (IQR 55-79) years. 12 (52.2%) patients were men. Peripheral monocytes and chemokine/cytokine profiles were analysed. RESULTS: Numbers of classical and non-classical monocytes were significantly decreased during acute SARS-CoV-2 infection compared to 3-month recovery. While classical monocytes reached the expected level in peripheral blood after 3 months, the number of non-classical monocytes remained significantly reduced. DISCUSSION: All three monocyte subsets exhibited changes of established adhesion and activation markers. Interestingly, they also expressed higher levels of pro-inflammatory cytokines like macrophage migration inhibitory factor (MIF) at the time of recovery, although MIF was only slightly increased during the acute phase. CONCLUSION: Changes of monocyte phenotypes and increased MIF expression after 3-month recovery from acute SARS-CoV-2 infection may indicate persistent, possibly long-lasting, pro-inflammatory monocyte function in CVD patients.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Monócitos , Citocinas , Quimiocinas
6.
ACS Omega ; 6(9): 6404-6413, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33718731

RESUMO

The emergence of a new strain of coronavirus in late 2019, SARS-CoV-2, led to a global pandemic in 2020. This may have been preventable if large scale, rapid diagnosis of active cases had been possible, and this has highlighted the need for more effective and efficient ways of detecting and managing viral infections. In this work, we investigate three different optical techniques for quantifying the binding of recombinant SARS-CoV-2 spike protein to surface-immobilized oligonucleotide aptamers. Biolayer interferometry is a relatively cheap, robust, and rapid method that only requires very small sample volumes. However, its detection limit of 250 nM means that it is not sensitive enough to detect antigen proteins at physiologically relevant levels (sub-pM). Surface plasmon resonance is a more sensitive technique but requires larger sample volumes, takes longer, requires more expensive instrumentation, and only reduces the detection limit to 5 nM. Surface-enhanced Raman spectroscopy is far more sensitive, enabling detection of spike protein to sub-picomolar concentrations. Control experiments performed using scrambled aptamers and using bovine serum albumin as an analyte show that this apta-sensing approach is both sensitive and selective, with no appreciable response observed for any controls. Overall, these proof-of-principle results demonstrate that SERS-based aptasensors hold great promise for development into rapid, point-of-use antigen detection systems, enabling mass testing without any need for reagents or laboratory expertise and equipment.

7.
Clin Rehabil ; 35(8): 1164-1174, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33685232

RESUMO

OBJECTIVE: To explore whether a structured counselling-based intervention increases vigorous physical activity behaviour of adolescent and young adult cancer survivors. DESIGN: Randomized controlled phase II trial. SETTING: University Cancer Center Hamburg, Germany. SUBJECTS: Eighty-nine participants (mean age 24.1 ± 6.3) were randomized to control (n = 44) or intervention group (n = 45). INTERVENTIONS: The intervention group was consulted about physical activity behaviour via interview (week 0), and telephone counselling (weeks 1, 3 and 12). The control group only received general physical activity guidelines for cancer survivors (week 0). MAIN MEASURES: The primary outcome was the rate of participants with ⩾9 metabolic equivalent (MET)-hours per week of vigorous activity post-intervention, measured with the International Physical Activity Questionnaire. Secondary outcomes included assessing physical activity behaviour (e.g. amount and type of physical activity) and quality of life. Assessments were completed in weeks 0 (baseline), 12 (post-intervention) and 52 (follow-up). RESULTS: Sixty-nine participants completed the post-intervention- and 47 the follow-up-assessment. The rate of participants performing vigorous physical activity increased from baseline to post-intervention for both without differing significantly (P = 0.541). Both increased their total metabolic equivalent from baseline to post-intervention (intervention group from 55.2 ± 43.7 to 61.7 ± 29.4, control group from 75.3 ± 81.4 to 88.3 ± 80.2). At follow-up the intervention group (73.7 ± 80.2) was more active than baseline when compared to the control group (78.5 ± 50.0). CONCLUSIONS: A structured counselling-based physical activity intervention did not significantly impact the level of vigorous physical activity behaviour in adolescent and young adult cancer survivors.


Assuntos
Sobreviventes de Câncer/psicologia , Aconselhamento/métodos , Exercício Físico/psicologia , Adolescente , Adulto , Metabolismo Energético/fisiologia , Feminino , Alemanha , Humanos , Masculino , Motivação , Neoplasias/terapia , Qualidade de Vida , Telefone , Adulto Jovem
8.
Clin Transl Immunology ; 10(3): e1261, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747511

RESUMO

OBJECTIVES: Circulating antibodies are important markers of previous infection and immunity. Questions remain with respect to the durability and functionality of SARS-CoV-2 antibodies. This study explored antibody responses in recovered COVID-19 patients in a setting where the probability of re-exposure is effectively nil, owing to New Zealand's successful elimination strategy. METHODS: A triplex bead-based assay that detects antibody isotype (IgG, IgM and IgA) and subclass (IgG1, IgG2, IgG3 and IgG4) responses against Nucleocapsid (N) protein, the receptor binding domain (RBD) and Spike (S) protein of SARS-CoV-2 was developed. After establishing baseline levels with pre-pandemic control sera (n = 113), samples from PCR-confirmed COVID-19 patients with mild-moderate disease (n = 189) collected up to 8 months post-infection were examined. The relationship between antigen-specific antibodies and neutralising antibodies (NAbs) was explored with a surrogate neutralisation assay that quantifies inhibition of the RBD/hACE-2 interaction. RESULTS: While most individuals had broad isotype and subclass responses to each antigen shortly after infection, only RBD and S protein IgG, as well as NAbs, were relatively stable over the study period, with 99%, 96% and 90% of samples, respectively, having responses over baseline 4-8 months post-infection. Anti-RBD antibodies were strongly correlated with NAbs at all time points (Pearson's r ≥ 0.87), and feasibility of using finger prick sampling to accurately measure anti-RBD IgG was demonstrated. CONCLUSION: Antibodies to SARS-CoV-2 persist for up to 8 months following mild-to-moderate infection. This robust response can be attributed to the initial exposure without immune boosting given the lack of community transmission in our setting.

9.
PeerJ ; 8: e9863, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32953275

RESUMO

BACKGROUND: Serological assays that detect antibodies to SARS-CoV-2 are critical for determining past infection and investigating immune responses in the COVID-19 pandemic. We established ELISA-based immunoassays using locally produced antigens when New Zealand went into a nationwide lockdown and the supply chain of diagnostic reagents was a widely held domestic concern. The relationship between serum antibody binding measured by ELISA and neutralising capacity was investigated using a surrogate viral neutralisation test (sVNT). METHODS: A pre-pandemic sera panel (n = 113), including respiratory infections with symptom overlap with COVID-19, was used to establish assay specificity. Sera from PCR­confirmed SARS-CoV-2 patients (n = 21), and PCR-negative patients with respiratory symptoms suggestive of COVID-19 (n = 82) that presented to the two largest hospitals in Auckland during the lockdown period were included. A two-step IgG ELISA based on the receptor binding domain (RBD) and spike protein was adapted to determine seropositivity, and neutralising antibodies that block the RBD/hACE­2 interaction were quantified by sVNT. RESULTS: The calculated cut-off (>0.2) in the two-step ELISA maximised specificity by classifying all pre-pandemic samples as negative. Sera from all PCR-confirmed COVID-19 patients were classified as seropositive by ELISA ≥7 days after symptom onset. There was 100% concordance between the two-step ELISA and the sVNT with all 7+ day sera from PCR­confirmed COVID-19 patients also classified as positive with respect to neutralising antibodies. Of the symptomatic PCR-negative cohort, one individual with notable travel history was classified as positive by two-step ELISA and sVNT, demonstrating the value of serology in detecting prior infection. CONCLUSIONS: These serological assays were established and assessed at a time when human activity was severely restricted in New Zealand. This was achieved by generous sharing of reagents and technical expertise by the international scientific community, and highly collaborative efforts of scientists and clinicians across the country. The assays have immediate utility in supporting clinical diagnostics, understanding transmission in high-risk cohorts and underpinning longer­term 'exit' strategies based on effective vaccines and therapeutics.

10.
Ecol Evol ; 10(3): 1489-1509, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32076529

RESUMO

Retention forestry, which retains a portion of the original stand at the time of harvesting to maintain continuity of structural and compositional diversity, has been originally developed to mitigate the impacts of clear-cutting. Retention of habitat trees and deadwood has since become common practice also in continuous-cover forests of Central Europe. While the use of retention in these forests is plausible, the evidence base for its application is lacking, trade-offs have not been quantified, it is not clear what support it receives from forest owners and other stakeholders and how it is best integrated into forest management practices. The Research Training Group ConFoBi (Conservation of Forest Biodiversity in Multiple-use Landscapes of Central Europe) focusses on the effectiveness of retention forestry, combining ecological studies on forest biodiversity with social and economic studies of biodiversity conservation across multiple spatial scales. The aim of ConFoBi is to assess whether and how structural retention measures are appropriate for the conservation of forest biodiversity in uneven-aged and selectively harvested continuous-cover forests of temperate Europe. The study design is based on a pool of 135 plots (1 ha) distributed along gradients of forest connectivity and structure. The main objectives are (a) to investigate the effects of structural elements and landscape context on multiple taxa, including different trophic and functional groups, to evaluate the effectiveness of retention practices for biodiversity conservation; (b) to analyze how forest biodiversity conservation is perceived and practiced, and what costs and benefits it creates; and (c) to identify how biodiversity conservation can be effectively integrated in multi-functional forest management. ConFoBi will quantify retention levels required across the landscape, as well as the socio-economic prerequisites for their implementation by forest owners and managers. ConFoBi's research results will provide an evidence base for integrating biodiversity conservation into forest management in temperate forests.

11.
Curr Top Microbiol Immunol ; 425: 277-296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31807895

RESUMO

Proper structure and function of the fungal cell wall are controlled by metabolic processes, as well as an interplay between a range of cellular organelles. Somewhat surprisingly, mitochondrial function has been shown to be important for proper cell wall biogenesis and integrity. Mitochondria also play a role in the susceptibility of fungi to cell wall-targeting drugs. This is true in a range of fungal species, including important human fungal pathogens. The biochemical mechanisms that explain the roles of mitochondria in cell wall biology have remained elusive, but studies to date strongly support the idea that mitochondrial control over cellular lipid homeostasis is at the core of these processes. Excitingly, recent evidence suggests that the mitochondria-lipid linkages drive resistance to the echinocandin drug caspofungin, a clinically important therapeutic that targets cell wall biosynthesis. Here, we review the state of affairs in mitochondria-fungal cell wall research and propose models that could be tested in future studies. Elucidating the mechanisms that drive fungal cell wall integrity through mitochondrial functions holds promise for developing new strategies to combat fungal infections, including the possibility to potentiate the effects of antifungal drugs and curb drug resistance.


Assuntos
Parede Celular , Fungos/citologia , Fungos/patogenicidade , Mitocôndrias/metabolismo , Micoses/microbiologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Parede Celular/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Fungos/efeitos dos fármacos , Humanos , Micoses/tratamento farmacológico
12.
Commun Biol ; 2: 315, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31453379

RESUMO

Glioblastoma (GBM) is one of the most aggressive solid tumors for which treatment options and biomarkers are limited. Small extracellular vesicles (sEVs) produced by both GBM and stromal cells are central in the inter-cellular communication that is taking place in the tumor bulk. As tumor sEVs are accessible in biofluids, recent reports have suggested that sEVs contain valuable biomarkers for GBM patient diagnosis and follow-up. The aim of the current study was to describe the protein content of sEVs produced by different GBM cell lines and patient-derived stem cells. Our results reveal that the content of the sEVs mirrors the phenotypic signature of the respective GBM cells, leading to the description of potential informative sEV-associated biomarkers for GBM subtyping, such as CD44. Overall, these data could assist future GBM in vitro studies and provide insights for the development of new diagnostic and therapeutic methods as well as personalized treatment strategies.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/metabolismo , Vesículas Extracelulares/metabolismo , Glioblastoma/classificação , Glioblastoma/metabolismo , Astrócitos/metabolismo , Astrócitos/patologia , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Vesículas Extracelulares/ultraestrutura , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Invasividade Neoplásica
13.
Cancer Manag Res ; 11: 4493-4504, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191011

RESUMO

PURPOSE: Two-thirds of cancer patients report taste disorders during and after chemotherapy. Taste disorders impact on nutritional status which is highly relevant for treatment efficacy and overall prognosis. Improvement of taste disorder is of particular importance for cancer patients' outcomes, thus the TASTE trial was conducted to improve taste disorders with a taste and smell training. METHODS: In this trial, patients undergoing chemotherapy were screened for taste disorders. Subsequently, patients were allocated based on the detection of taste disorders (≤8 taste strips points) to an intervention group with a taste and smell training at baseline and week 3-5 or were only followed up, if no taste disorder was detected (≥9 taste strips points) (non-intervention group). At baseline, all patients received a nutritional counseling. The primary endpoint was the minimal clinically relevant improvement of taste strips score by 2 taste strips points in at least 50% of the patients with taste disorders. RESULTS: The trial included 62 patients (48 women [77%], 14 male [23%], age 54.5±11.6 years) who had gastrointestinal (n=29), breast (n=31), or lung cancer (n=2). Taste disorders were more frequent in gastrointestinal than in breast cancer patients. Out of 62 patients screened, 30 patients showed taste disorders. The primary endpoint was met with 92% (n=23 of 25) of the patients completing the intervention. In the intervention group, the patients' taste significantly improved from baseline (median taste strips: 7.0 points) to week 12 (median taste strips: 10.0 points) (P≤0.001). Patients of the non-intervention group who completed the reassessment (n=27 of 32) experienced no change in taste perception in the 3-month follow-up (P=0.897). CONCLUSION: Intensified nutritional counseling with taste and smell training may improve taste perception of patients undergoing chemotherapy. A confirmatory randomized trial is planned.

14.
Curr Genet ; 65(4): 837-845, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30783741

RESUMO

Mitochondrial fission shows potential as a therapeutic target in non-infectious human diseases. The compound mdivi-1 was identified as a mitochondrial fission inhibitor that acts against the evolutionarily conserved mitochondrial fission GTPase Dnm1/Drp1, and shows promising data in pre-clinical models of human pathologies. Two recent studies, however, found no evidence that mdivi-1 acts as a mitochondrial fission inhibitor and proposed other mechanisms. In mammalian cells, Bordt et al. showed that mdivi-1 inhibits complex I in mitochondria (Dev Cell 40:583, 2017). In a second study, we have recently demonstrated that mdivi-1 does not trigger a mitochondrial morphology change in the human yeast pathogen Candida albicans, but impacts on endogenous nitric oxide (NO) levels and inhibits the key virulence property of hyphal formation (Koch et al., Cell Rep 25:2244, 2018). Here we discuss recent insights into mdivi-1's action in pathogenic fungi and the potential and challenges for repurposing it as an anti-infective. We also outline recent findings on the roles of mitochondrial fission in human and plant fungal pathogens, with the goal of starting the conversation on whether the research field of fungal pathogenesis can benefit from efforts in other disease areas aimed at developing therapeutic inhibitors of mitochondrial division.


Assuntos
Fungos/efeitos dos fármacos , Mitocôndrias/genética , Dinâmica Mitocondrial/genética , Quinazolinonas/farmacologia , Apoptose/genética , Complexo I de Transporte de Elétrons/genética , Fungos/patogenicidade , GTP Fosfo-Hidrolases/genética , Humanos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Hifas/patogenicidade , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Óxido Nítrico/genética , Óxido Nítrico/metabolismo
15.
Cell Rep ; 25(8): 2244-2258.e7, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30463019

RESUMO

The yeast Candida albicans colonizes several sites in the human body and responds to metabolic signals in commensal and pathogenic states. The yeast-to-hyphae transition correlates with virulence, but how metabolic status is integrated with this transition is incompletely understood. We used the putative mitochondrial fission inhibitor mdivi-1 to probe the crosstalk between hyphal signaling and metabolism. Mdivi-1 repressed C. albicans hyphal morphogenesis, but the mechanism was independent of its presumed target, the mitochondrial fission GTPase Dnm1. Instead, mdivi-1 triggered extensive metabolic reprogramming, consistent with metabolic stress, and reduced endogenous nitric oxide (NO) levels. Limiting endogenous NO stabilized the transcriptional repressor Nrg1 and inhibited the yeast-to-hyphae transition. We establish a role for endogenous NO signaling in C. albicans hyphal morphogenesis and suggest that NO regulates a metabolic checkpoint for hyphal growth. Furthermore, identifying NO signaling as an mdivi-1 target could inform its therapeutic applications in human diseases.


Assuntos
Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais , Animais , Caenorhabditis elegans , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hifas/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Dinâmica Mitocondrial/efeitos dos fármacos , Modelos Biológicos , Morfogênese/efeitos dos fármacos , Quinazolinonas/farmacologia , Proteínas Repressoras/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas ras/metabolismo
16.
Front Microbiol ; 8: 2295, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209301

RESUMO

HsAFP1, a plant defensin isolated from coral bells (Heuchera sanguinea), is characterized by broad-spectrum antifungal activity. Previous studies indicated that HsAFP1 binds to specific fungal membrane components, which had hitherto not been identified, and induces mitochondrial dysfunction and cell membrane permeabilization. In this study, we show that HsAFP1 reversibly interacts with the membrane phospholipid phosphatidic acid (PA), which is a precursor for the biosynthesis of other phospholipids, and to a lesser extent with various phosphatidyl inositol phosphates (PtdInsP's). Moreover, via reverse ELISA assays we identified two basic amino acids in HsAFP1, namely histidine at position 32 and arginine at position 52, as well as the phosphate group in PA as important features enabling this interaction. Using a HsAFP1 variant, lacking both amino acids (HsAFP1[H32A][R52A]), we showed that, as compared to the native peptide, the ability of this variant to bind to PA and PtdInsP's is reduced (≥74%) and the antifungal activity of the variant is reduced (≥2-fold), highlighting the link between PA/PtdInsP binding and antifungal activity. Using fluorescently labelled HsAFP1 in confocal microscopy and flow cytometry assays, we showed that HsAFP1 accumulates at the cell surface of yeast cells with intact membranes, most notably at the buds and septa. The resulting HsAFP1-induced membrane permeabilization is likely to occur after HsAFP1's internalization. These data provide novel mechanistic insights in the mode of action of the HsAFP1 plant defensin.

17.
Arch Toxicol ; 91(12): 3823-3833, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28612261

RESUMO

Antimony is utilized in a large variety of industrial applications, leading to significant environmental and occupational exposure. Mainly based on animal experiments, the IARC and MAK Commission have classified antimony and its inorganic compounds as Group 2B or 2 carcinogens, respectively. However, the underlying mode(s) of action are still largely unknown. In the present study, we investigated the impact of non-cytotoxic up to cytotoxic concentrations of SbCl3 on DNA DSB repair and cell cycle control in HeLa S3 cells. We induced DSB by γ-irradiation and analyzed inhibitory actions of antimony on potential molecular targets of the DSB repair machinery. Antimony disturbed cell cycle control, affecting phosphorylation of Chk1. Furthermore, the repair of DSB was impaired in the presence of antimony, as monitored by pulsed-field gel electrophoresis and γH2AX foci formation of cells in G1 and G2 phase. Specifically, BRCA1 and RAD51 were identified as molecular targets. Our results point towards an interference with both non-homologous end-joining (NHEJ) and homologous recombination (HR), and inhibitory effects may be explained by interactions with critical cysteine groups; this needs to be further investigated. Altogether, the results provide further evidence for the impairment of DNA repair processes as one underlying mechanism in antimony-induced carcinogenicity.


Assuntos
Antimônio/toxicidade , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Antimônio/administração & dosagem , Proteína BRCA1/genética , Ciclo Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Dano ao DNA/efeitos da radiação , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Reparo do DNA/efeitos da radiação , Células HeLa , Recombinação Homóloga/efeitos dos fármacos , Humanos , Rad51 Recombinase/genética , Radiação Ionizante
18.
Psychooncology ; 26(12): 2127-2134, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28370730

RESUMO

OBJECTIVE: We developed an integrative day care clinic program for cancer patients focusing on mind-body techniques and health-promoting lifestyle modification (7-hour once-per-week group sessions over 12 weeks). METHODS: A cohort study design with a waiting group was implemented. Outcome parameters were assessed at the beginning, at the end of the active program, and at a 6-month follow-up. Patients waiting >4 and <12 weeks before treatment start were allocated to the waiting group and additionally assessed at the start of their day care program. Outcome measures included quality of life (FACT-G, FACT-B/C, WHO-5), fatigue (FACIT-F), depression/anxiety (HADS), and mood states (ASTS). A per protocol analysis using mixed linear models was performed. RESULTS: One hundred patients were screened on-site for eligibility. Eighty-six cancer survivors (83% female; mean age 53.7 ± 9.7 years; 49% breast cancer) were included into the study. Sixty-two patients were allocated to the intervention group and 24 patients, to the waiting group (mean waiting time 5 ± 1 weeks). Sixty-six data sets were included in the final analysis. Significant improvements were observed in favor of the intervention group after 12 weeks compared with the waiting group at the end of the waiting period for quality of life, anxiety/depression, and fatigue. Results from the 6-month follow-up for the whole study population showed lasting improvement of quality of life. CONCLUSIONS: The program can be considered as an effective means to improve quality of life, fatigue, and mental health of cancer patients. Moreover, it appears to have a sustainable effect, which has to be proved in randomized trials.


Assuntos
Terapia Comportamental/métodos , Neoplasias da Mama/terapia , Estilo de Vida , Terapias Mente-Corpo/métodos , Atenção Plena/métodos , Qualidade de Vida/psicologia , Adulto , Afeto , Idoso , Instituições de Assistência Ambulatorial , Neoplasias da Mama/psicologia , Estudos de Coortes , Hospital Dia , Depressão/terapia , Fadiga , Feminino , Humanos , Saúde Mental , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
19.
J Adolesc Young Adult Oncol ; 6(2): 194-199, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27983882

RESUMO

Adolescents and young adults (AYAs) with hemato-oncological problems constitute a heterogenous group with characteristic particularities, specific needs, and age-related clinical and unique psychosocial features. Strong collaboration between pediatric and adult hemato-oncology settings is essential to address their needs appropriately. This is not only true for patients who first become ill during adolescence or young adulthood, but equally so for people who contract hemato-oncological diseases congenitally or as younger children and who are now becoming old enough to leave the pediatric setting and have to transit into "adult" medical care. Efforts to create environments that meet the specific needs of the AYA population affected by hemato-oncological diseases have been initiated in many countries. Due to international variations between societies in general and healthcare infrastructures in particular, the challenges posed to creating such environments vary considerably from country to country. Aiming at addressing these on a national basis for Germany, a dedicated Working Group on Adolescents, Young Adults, and Transition (Arbeitsgemeinschaft Adoleszenten, junge Erwachsene, Transition, AjET) was established. This meeting report depicts the content and discussions of the first interdisciplinary conference on treatment, transition, and long-term follow-up in AYAs with cancer or chronic/inborn hematological diseases. The AjET group of the German Society for Pediatric Oncology and Hematology (GPOH) intends to increase the national awareness for AYAs; strengthen the collaboration of pediatric and adult care givers; and initiate, promote, and coordinate collaborative activities in the fields of basic and translational research, clinical care, and long-term follow-up aimed at improving the current situation.


Assuntos
Atenção à Saúde/organização & administração , Doenças Hematológicas/terapia , Hematologia/organização & administração , Oncologia/organização & administração , Neoplasias/terapia , Pediatria/organização & administração , Transição para Assistência do Adulto/organização & administração , Adolescente , Adulto , Sobreviventes de Câncer , Congressos como Assunto , Alemanha , Humanos , Sociedades Médicas , Adulto Jovem
20.
Front Microbiol ; 8: 2555, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29326680

RESUMO

The interactions of mitochondria with the endoplasmic reticulum (ER) are crucial for maintaining proper mitochondrial morphology, function and dynamics. This enables cells to utilize their mitochondria optimally for energy production and anabolism, and it further provides for metabolic control over developmental decisions. In fungi, a key mechanism by which ER and mitochondria interact is via a membrane tether, the protein complex ERMES (ER-Mitochondria Encounter Structure). In the model yeast Saccharomyces cerevisiae, the mitochondrial GTPase Gem1 interacts with ERMES, and it has been proposed to regulate its activity. Here we report on the first characterization of Gem1 in a human fungal pathogen. We show that in Candida albicans Gem1 has a dominant role in ensuring proper mitochondrial morphology, and our data is consistent with Gem1 working with ERMES in this role. Mitochondrial respiration and steady state cellular phospholipid homeostasis are not impacted by inactivation of GEM1 in C. albicans. There are two major virulence-related consequences of disrupting mitochondrial morphology by GEM1 inactivation: C. albicans becomes hypersusceptible to cell wall stress, and is unable to grow invasively. In the gem1Δ/Δ mutant, it is specifically the invasive capacity of hyphae that is compromised, not the ability to transition from yeast to hyphal morphology, and this phenotype is shared with ERMES mutants. As a consequence of the hyphal invasion defect, the gem1Δ/Δ mutant is drastically hypovirulent in the worm infection model. Activation of the mitogen activated protein (MAP) kinase Cek1 is reduced in the gem1Δ/Δ mutant, and this function could explain both the susceptibility to cell wall stress and lack of invasive growth. This result establishes a new, respiration-independent mechanism of mitochondrial control over stress signaling and hyphal functions in C. albicans. We propose that ER-mitochondria interactions and the ER-Mitochondria Organizing Network (ERMIONE) play important roles in adaptive responses in fungi, in particular cell surface-related mechanisms that drive invasive growth and stress responsive behaviors that support fungal pathogenicity.

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