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1.
Sensors (Basel) ; 24(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39001070

RESUMO

Monitoring the strain in the rotating flywheel in a kinetic energy storage system is important for safe operation and for the investigation of long-term effects in composite materials like carbon-fiber-reinforced plastics. An optoelectronic strain-measurement system for contactless deformation and position monitoring of a flywheel was investigated. The system consists of multiple optical sensors measuring the local relative in-plane displacement of the flywheel rotor. A special reflective pattern, which is necessary to interact with the sensors, was applied to the surface of the rotor. Combining the measurements from multiple sensors makes it possible to distinguish between the deformation and in-plane displacement of the flywheel. The sensor system was evaluated using a low-speed steel rotor for single-sensor performance investigation as well as a scaled-down high-speed rotor made from PVC plastic. The PVC rotor exhibits more deformation due to centrifugal stresses than a steel or aluminum rotor of the same dimensions, which allows experimental measurements at a smaller flywheel scale as well as a lower rotation speed. Deformation measurements were compared to expected deformation from calculations. The influence of sensor distance was investigated. Deformation and position measurements as well as derived imbalance measurements were demonstrated.

2.
Cell Mol Life Sci ; 79(6): 340, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35661927

RESUMO

Cerebral cavernous malformations (CCM) are low-flow vascular lesions prone to cause severe hemorrhage-associated neurological complications. Pathogenic germline variants in CCM1, CCM2, or CCM3 can be identified in nearly 100% of CCM patients with a positive family history. In line with the concept that tumor-like mechanisms are involved in CCM formation and growth, we here demonstrate an abnormally increased proliferation rate of CCM3-deficient endothelial cells in co-culture with wild-type cells and in mosaic human iPSC-derived vascular organoids. The observation that NSC59984, an anticancer drug, blocked the abnormal proliferation of mutant endothelial cells further supports this intriguing concept. Fluorescence-activated cell sorting and RNA sequencing revealed that co-culture induces upregulation of proangiogenic chemokine genes in wild-type endothelial cells. Furthermore, genes known to be significantly downregulated in CCM3-/- endothelial cell mono-cultures were upregulated back to normal levels in co-culture with wild-type cells. These results support the hypothesis that wild-type ECs facilitate the formation of a niche that promotes abnormal proliferation of mutant ECs. Thus, targeting the cancer-like features of CCMs is a promising new direction for drug development.


Assuntos
Células Endoteliais , Hemangioma Cavernoso do Sistema Nervoso Central , Proteínas Reguladoras de Apoptose/genética , Proliferação de Células , Técnicas de Cocultura , Células Endoteliais/patologia , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Proteínas Proto-Oncogênicas/genética
3.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36835400

RESUMO

Cerebral cavernous malformation (CCM) is a neurovascular disease that can lead to seizures and stroke-like symptoms. The familial form is caused by a heterozygous germline mutation in either the CCM1, CCM2, or CCM3 gene. While the importance of a second-hit mechanism in CCM development is well established, it is still unclear whether it immediately triggers CCM development or whether additional external factors are required. We here used RNA sequencing to study differential gene expression in CCM1 knockout induced pluripotent stem cells (CCM1-/- iPSCs), early mesoderm progenitor cells (eMPCs), and endothelial-like cells (ECs). Notably, CRISPR/Cas9-mediated inactivation of CCM1 led to hardly any gene expression differences in iPSCs and eMPCs. However, after differentiation into ECs, we found the significant deregulation of signaling pathways well known to be involved in CCM pathogenesis. These data suggest that a microenvironment of proangiogenic cytokines and growth factors can trigger the establishment of a characteristic gene expression signature upon CCM1 inactivation. Consequently, CCM1-/- precursor cells may exist that remain silent until entering the endothelial lineage. Collectively, not only downstream consequences of CCM1 ablation but also supporting factors must be addressed in CCM therapy development.


Assuntos
Diferenciação Celular , Hemangioma Cavernoso do Sistema Nervoso Central , Células-Tronco Pluripotentes Induzidas , Proteína KRIT1 , Transcriptoma , Humanos , Diferenciação Celular/genética , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteína KRIT1/genética , Proteínas Proto-Oncogênicas/genética , Microambiente Tumoral , Técnicas de Inativação de Genes
4.
Neurosurg Rev ; 45(1): 649-660, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34164745

RESUMO

The aim of this study is to analyze the long-term quality of life after surgery of cavernoma. A monocentric retrospective study was conducted on 69 patients with cavernoma treated microsurgically between 2000 and 2016. The eloquence was adopted from Spetzler-Martin definition. A most recent follow-up was elicited between 2017 and 2019, in which the quality of life (QoL) was evaluated with the Short Form-12 questionnaire (SF12). Forty-one lesions were in eloquent group (EG), 22 in non-eloquent group (NEG), 3 in orbit, and 3 in the spinal cord. Postoperative worsening of the modified Rankin scale (mRS) occurred in 19.5% of cases in EG versus 4.5% in NEG. After a mean follow-up of 6.5 years (SD 4.6), the neurological status was better or unchanged compared to baseline in 85.4% of EG and 100% of NEG. Regarding QoL assessment of 44 patients (EG n = 27, NEG n = 14) attended the last follow-up. Patients after eloquent cavernoma resection reported a non-inferior QoL in most SF12 domains (except for physical role) compared to NEG. However, they reported general health perception inferior to norms, which was affected by the limited physical and emotional roles. At a late follow-up, the surgical morbidity was transient in the NEG and mostly recovered in the EG. The QoL comparison between eloquent and non-eloquent cavernomas created interesting and new data after prolonged follow-up. These results add value for decision-making as well as patient counseling for future encountered cases. Preoperative evaluation of QoL is recommended for future studies to assess QoL dynamics.


Assuntos
Hemangioma Cavernoso , Qualidade de Vida , Hemangioma Cavernoso/cirurgia , Humanos , Cuidados Pré-Operatórios , Estudos Retrospectivos , Resultado do Tratamento
5.
Int J Mol Sci ; 23(19)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36232290

RESUMO

The cases of Lyme disease caused by Borrelia burgdorferi infection have been increasing throughout Northern America and Europe. This pathogen, if not treated in a timely manner with antibiotics, can cause persisting and debilitating health outcomes. In the search for novel agents against B. burgdorferi, we investigated a phenolic compound-gallic acid-for its anti-Borrelia and anti-inflammatory effects. Our results showed its biocidal effect starting from 100 µg/mL against active spirochetes, persisters/round-shaped bodies, and biofilm like aggregates of B. burgdorferi sensu stricto. Activation of macrophages by live B. burgdorferi also resulted in a robust NFκB-dependent proinflammatory responses seen in increased production of cytokines. Using human CD14+ macrophages in vitro, we showed that CD14+ adaptor and phosphorylated p65 molecule are impeded at nonbiocidal and noncytotoxic concentrations of gallic acid, resulting in the inhibition of both expression and secretion of cytokines IL1ß, IL6, and TNFα. Our findings demonstrate efficacy of gallic acid against B. burgdorferi and provide potential mechanistic insight into its TLR2/CD14+-NFκB mediated mode of action. Further studies on the potential of gallic acid as a safe and effective compound against Borrelia-caused infection are warranted.


Assuntos
Borrelia burgdorferi , Doença de Lyme , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Anti-Inflamatórios/metabolismo , Citocinas/metabolismo , Ácido Gálico/metabolismo , Ácido Gálico/farmacologia , Humanos , Interleucina-6/metabolismo , Receptores de Lipopolissacarídeos/imunologia , Doença de Lyme/tratamento farmacológico , NF-kappa B/metabolismo , Receptor 2 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555281

RESUMO

Deletions in the CCM1, CCM2, and CCM3 genes are a common cause of familial cerebral cavernous malformations (CCMs). In current molecular genetic laboratories, targeted next-generation sequencing or multiplex ligation-dependent probe amplification are mostly used to identify copy number variants (CNVs). However, both techniques are limited in their ability to specify the breakpoints of CNVs and identify complex structural variants (SVs). To overcome these constraints, we established a targeted Cas9-mediated nanopore sequencing approach for CNV detection with single nucleotide resolution. Using a MinION device, we achieved complete coverage for the CCM genes and determined the exact size of CNVs in positive controls. Long-read sequencing for a CCM1 and CCM2 CNV revealed that the adjacent ANKIB1 and NACAD genes were also partially or completely deleted. In addition, an interchromosomal insertion and an inversion in CCM2 were reliably re-identified by long-read sequencing. The refinement of CNV breakpoints by long-read sequencing enabled fast and inexpensive PCR-based variant confirmation, which is highly desirable to reduce costs in subsequent family analyses. In conclusion, Cas9-mediated nanopore sequencing is a cost-effective and flexible tool for molecular genetic diagnostics which can be easily adapted to various target regions.


Assuntos
Proteínas de Transporte , Variações do Número de Cópias de DNA , Sequenciamento por Nanoporos , Humanos , Proteínas de Transporte/genética , Sistemas CRISPR-Cas , Reação em Cadeia da Polimerase Multiplex
7.
FASEB J ; 34(7): 9018-9033, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32515053

RESUMO

Loss-of-function variants in CCM1/KRIT1, CCM2, and CCM3/PDCD10 are associated with autosomal dominant cerebral cavernous malformations (CCMs). CRISPR/Cas9-mediated CCM3 inactivation in human endothelial cells (ECs) has been shown to induce profound defects in cell-cell interaction as well as actin cytoskeleton organization. We here show that CCM3 inactivation impairs fibronectin expression and consequently leads to reduced fibers in the extracellular matrix. Despite the complexity and high molecular weight of fibronectin fibrils, our in vitro model allowed us to reveal that fibronectin supplementation restored aberrant spheroid formation as well as altered EC morphology, and suppressed actin stress fiber formation. Yet, fibronectin replacement neither enhanced the stability of tube-like structures nor inhibited the survival advantage of CCM3-/- ECs. Importantly, CRISPR/Cas9-mediated introduction of biallelic loss-of-function variants into either CCM1 or CCM2 demonstrated that the impaired production of a functional fibronectin matrix is a common feature of CCM1-, CCM2-, and CCM3-deficient ECs.


Assuntos
Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas de Transporte/antagonistas & inibidores , Endotélio Vascular/citologia , Fibronectinas/metabolismo , Proteína KRIT1/antagonistas & inibidores , Proteínas de Membrana/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Sistemas CRISPR-Cas , Proteínas de Transporte/genética , Células Cultivadas , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Fibronectinas/genética , Humanos , Proteína KRIT1/genética , Proteínas de Membrana/genética , Fenótipo , Proteínas Proto-Oncogênicas/genética
8.
J Exp Biol ; 224(24)2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34845497

RESUMO

For animals to survive until reproduction, it is crucial that juveniles successfully detect potential predators and respond with appropriate behavior. The recognition of cues originating from predators can be innate or learned. Cues of various modalities might be used alone or in multi-modal combinations to detect and distinguish predators but studies investigating multi-modal integration in predator avoidance are scarce. Here, we used wild, naive tadpoles of the Neotropical poison frog Allobates femoralis ( Boulenger, 1884) to test their reaction to cues with two modalities from two different sympatrically occurring potential predators: heterospecific predatory Dendrobates tinctorius tadpoles and dragonfly larvae. We presented A. femoralis tadpoles with olfactory or visual cues, or a combination of the two, and compared their reaction to a water control in a between-individual design. In our trials, A. femoralis tadpoles reacted to multi-modal stimuli (a combination of visual and chemical information) originating from dragonfly larvae with avoidance but showed no reaction to uni-modal cues or cues from heterospecific tadpoles. In addition, visual cues from conspecifics increased swimming activity while cues from predators had no effect on tadpole activity. Our results show that A. femoralis tadpoles can innately recognize some predators and probably need both visual and chemical information to effectively avoid them. This is the first study looking at anti-predator behavior in poison frog tadpoles. We discuss how parental care might influence the expression of predator avoidance responses in tadpoles.


Assuntos
Odonatos , Venenos , Animais , Sinais (Psicologia) , Larva/fisiologia , Comportamento Predatório , Ranidae/fisiologia
9.
J Med Genet ; 57(3): 212-216, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31446422

RESUMO

BACKGROUND: Cerebral cavernous malformations (CCMs) can cause severe neurological morbidity but our understanding of the mechanisms that drive CCM formation and growth is still incomplete. Recent experimental data suggest that dysfunctional CCM3-deficient endothelial cell clones form cavernous lesions in conjunction with normal endothelial cells. OBJECTIVE: In this study, we addressed the question whether endothelial cell mosaicism can be found in human cavernous tissue of CCM1 germline mutation carriers. METHODS AND RESULTS: Bringing together single-molecule molecular inversion probes in an ultra-sensitive sequencing approach with immunostaining to visualise the lack of CCM1 protein at single cell resolution, we identified a novel late postzygotic CCM1 loss-of-function variant in the cavernous tissue of a de novo CCM1 germline mutation carrier. The extended unilateral CCM had been located in the right central sulcus causing progressive proximal paresis of the left arm at the age of 15 years. Immunohistochemical analyses revealed that individual caverns are lined by both heterozygous (CCM1+/- ) and compound heterozygous (CCM1-/- ) endothelial cells. CONCLUSION: We here demonstrate endothelial cell mosaicism within single caverns of human CCM tissue. In line with recent in vitro data on CCM1-deficient endothelial cells, our results provide further evidence for clonal evolution in human CCM1 pathogenesis.


Assuntos
Predisposição Genética para Doença , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Proteína KRIT1/genética , Mosaicismo , Adolescente , Proteínas Reguladoras de Apoptose/genética , Proteínas de Transporte/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Mutação em Linhagem Germinativa/genética , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Zigoto/patologia
10.
Sensors (Basel) ; 21(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34960486

RESUMO

The strain in a fast spinning carbon fiber flywheel rotor is of great interest for condition monitoring, as well as for studying long-term aging effects in the carbon fiber matrix. Optoelectronic strain measurement is a contactless measurement principle where a special reflective pattern is applied to the rotor which is scanned by a stationary optical setup. It does not require any active electronic components on the rotor and is suited for operation in a vacuum. In this paper, the influences of the key parts comprising the optoelectronic strain measurement are analyzed. The influence of each part on the measurement result including the uncertainty is modeled. The total uncertainty, as well as each part's contribution is calculated. This provides a valuable assessment of requirements for component selection, as well as tolerances of mechanical parts and processes to reach a final target measurement uncertainty or to estimate the uncertainty of a given setup. We have shown that the edge quality of the special reflective pattern has the strongest influence, and how to improve it. Considering all influences, it is possible to measure strain with an uncertainty of less than 1% at a rotation speed of 500Hz.

11.
J Cell Mol Med ; 23(3): 1771-1783, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30549232

RESUMO

CCM3, originally described as PDCD10, regulates blood-brain barrier integrity and vascular maturation in vivo. CCM3 loss-of-function variants predispose to cerebral cavernous malformations (CCM). Using CRISPR/Cas9 genome editing, we here present a model which mimics complete CCM3 inactivation in cavernous endothelial cells (ECs) of heterozygous mutation carriers. Notably, we established a viral- and plasmid-free crRNA:tracrRNA:Cas9 ribonucleoprotein approach to introduce homozygous or compound heterozygous loss-of-function CCM3 variants into human ECs and studied the molecular and functional effects of long-term CCM3 inactivation. Induction of apoptosis, sprouting, migration, network and spheroid formation were significantly impaired upon prolonged CCM3 deficiency. Real-time deformability cytometry demonstrated that loss of CCM3 induces profound changes in cell morphology and mechanics: CCM3-deficient ECs have an increased cell area and elastic modulus. Small RNA profiling disclosed that CCM3 modulates the expression of miRNAs that are associated with endothelial ageing. In conclusion, the use of CRISPR/Cas9 genome editing provides new insight into the consequences of long-term CCM3 inactivation in human ECs and supports the hypothesis that clonal expansion of CCM3-deficient dysfunctional ECs contributes to CCM formation.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Evolução Clonal , Endotélio Vascular/patologia , Proteínas de Membrana/metabolismo , Mutação , Neovascularização Patológica/etiologia , Proteínas Proto-Oncogênicas/metabolismo , Alelos , Apoptose , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Sistemas CRISPR-Cas , Endotélio Vascular/metabolismo , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , MicroRNAs/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética
12.
Am J Med Genet A ; 179(2): 295-299, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30556293

RESUMO

Grange syndrome is an autosomal recessive condition characterized by arterial occlusions and hypertension. Syndactyly, brachydactyly, bone fragility, heart defects, and learning disabilities have also been reported. Loss-of-function variants in YY1AP1 have only recently been associated with Grange syndrome. YY1AP1 encodes for the transcription coactivator yin yang 1-associated protein 1 which regulates smooth muscle cell proliferation and differentiation. We here report on three siblings with steno-occlusive arterial disorder and syndactyly in two of them. Whole exome sequencing including near-splice regions led to the identification of two intronic YY1AP1 variants which were predicted to interfere with normal splicing. Sanger sequencing demonstrated compound-heterozygosity in all affected siblings. RT-PCR analyses confirmed skipping of exon 6 on one allele and exonization of 22 bp in intron 6 on the other. This is the first report of biallelic YY1AP1 variants in noncoding regions and just the second family with multiple affected siblings. Therefore, our report further delineates the phenotypic spectrum of Grange syndrome.


Assuntos
Arteriopatias Oclusivas/genética , Osso e Ossos/anormalidades , Braquidactilia/genética , Proteínas de Ciclo Celular/genética , Predisposição Genética para Doença , Cardiopatias Congênitas/genética , Hipertensão/genética , Sindactilia/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Arteriopatias Oclusivas/fisiopatologia , Osso e Ossos/fisiopatologia , Braquidactilia/fisiopatologia , Criança , Feminino , Cardiopatias Congênitas/fisiopatologia , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Linhagem , Isoformas de Proteínas/genética , Sindactilia/fisiopatologia , Sequenciamento do Exoma
13.
BMC Complement Altern Med ; 19(1): 40, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717726

RESUMO

BACKGROUND: Borrelia sp. is a causative pathogen of Lyme disease which has become a worldwide health concern. Non-toxic approaches especially directed toward latent persistent forms of this pathogen are desired. Lipids in the form of volatile and non-volatile oils, and fatty acids with proven anti-borreliae efficacy could become an additional support or an alternative for consideration in treatment approaches. METHODS: In this study we investigated 47 lipids (30 volatile and non-volatile oils, and 17 fatty acids) of plant and animal origin against typical motile, knob/round-shaped persisters, and biofilm-like aggregates of Borrelia burgdorferi s.s. and Borrelia garinii, which are identified as pathogenic factors of Lyme disease in the USA and Europe, using direct microscopic counting and spectrofluorometric measurements. RESULTS: Out of all examined lipids, 5 oils (Bay leaf oil, Birch oil, Cassia oil, Chamomile oil German, and Thyme oil) at or below 0.25%, and 3 fatty acids (13Z,16Z Docosadienoic acid, erucic acid, and petroselinic acid) at or below 0.75 mg/ml, showed bactericidal activity against typical motile spirochetes and knob/round-shaped persisters. Only Bay leaf oil and Cassia oil, including their major constituents, eugenol and cinnamaldehyde, showed to target biofilm-like aggregates of both tested Borrelia spp. at the same concentration, although with 20-30% eradication mark. CONCLUSION: Based on obtained results, volatile oils were more potent than non-volatile oils, and unsaturated fatty acids were more effective than saturated fatty acids. Among all tested oils, Bay leaf oil and Cassia oil, with their major components eugenol and cinnamaldehyde, seem to have the highest anti-borreliae efficacy.


Assuntos
Antibacterianos/farmacologia , Borrelia/efeitos dos fármacos , Ácidos Graxos/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Animais , Biofilmes/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos
14.
Neurogenetics ; 19(1): 55-59, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29197946

RESUMO

Familial cerebral cavernous malformations (CCMs) predispose to seizures and hemorrhagic stroke. Molecular genetic analyses of CCM1, CCM2, and CCM3 result in a mutation detection rate of up to 98%. However, only whole genome sequencing (WGS) in combination with the Manta algorithm for analyses of structural variants revealed a heterozygous 24 kB inversion including exon 1 of CCM2 in a 12-year-old boy with familial CCMs. Its breakpoints were fine-mapped, and quantitative analysis on RNA confirmed reduced CCM2 expression. Our data expand the spectrum of CCM mutations and indicate that the existence of a fourth CCM disease gene is rather unlikely.


Assuntos
Proteínas de Transporte/genética , Inversão Cromossômica , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Criança , Estudo de Associação Genômica Ampla , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Masculino , Linhagem , Sequenciamento Completo do Genoma
15.
Microorganisms ; 12(8)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39203455

RESUMO

Streptococcus mutans is a major pathogenic habitant of oral caries. Owing to its physiological and biochemical features, it prevails in the form of plaque biofilm together with another important mutans streptococci species, Streptococcus sobrinus. Both species are considered as initiators of cavity lesions, and biofilm is essential to the dental caries process. Compared with the planktonic populations, the biofilm form has higher resistance to environmental conditions and antibiotics. Dental plaques also secure the long-term survival of microorganisms and protection from any stress conditions. To address the need for new antibiofilm agents, we have focused on L-carnitine-fumarate, a fumarate-conjugated quaternary ammonium compound. Using the macro-broth susceptibility testing method, we established its MIC value as 6.0 mg/mL. The MBC value, determined from the broth dilution minimum inhibitory concentration test by sub-culturing it to BHI agar plates, was established as 7.0 mg/mL. Antibiofilm efficacy was tested in 96-well plates coated with saliva using BHI broth supplemented with 1% sucrose as a standard approach. The obtained results allowed us to assess the MIBC as 7.5 mg/mL and the MBBC value as 10.0 mg/mL. The latter concentration also caused approximately 20% eradication of pre-existing biofilm. EPS-rich matrix, forming the core of the biofilm and enabling a confined acidic microenvironment, was also examined and confirmed the effectiveness of 10.0 mg/mL L-carnitine-fumarate concentration in inhibiting EPS formation. Furthermore, the anti-adherent and anti-aciduric impacts of L-carnitine-fumarate were investigated and revealed significant inhibitory effects at sub-MIC concentrations. The influence of L-carnitine-fumarate on the phosphotransferase system was investigated as well. Our results provide a new insight into the antibacterial potential of L-carnitine-fumarate as a valuable compound to be considered for alternative or adjunct anti-caries and antibiofilm preventive approaches.

16.
J Thromb Haemost ; 22(4): 1179-1186, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38103735

RESUMO

BACKGROUND: The transcription factor GATA1 is an essential regulator of erythroid cell gene expression and maturation and is also relevant for platelet biogenesis. GATA1-related thrombocytopenia (GATA1-RT) is a rare X-linked inherited platelet disorder (IPD) characterized by macrothrombocytopenia and dyserythropoiesis. Enlarged platelet size, reduced platelet granularity, and noticeable red blood cell anisopoikilocytosis are characteristic but unspecific morphological findings in GATA1-RT. OBJECTIVES: To expand the investigation of platelet phenotype of patients with GATA1-RT by light- and immunofluorescence microscopy on a blood smear. METHODS: We assessed blood smears by light- and immunofluorescence microscopy after May-Grünwald Giemsa staining using a set of 13 primary antibodies against markers belonging to different platelet structures. Antibody binding was visualized by fluorescently labeled secondary antibodies. RESULTS: We investigated 12 individuals with genetically confirmed GATA1-RT from 8 unrelated families. While confirming the already known characteristic of platelet morphology (platelet macrocytosis and reduced expression of markers for α-granules), we also found aggregates of nonmuscular myosin heavy chain II A (NMMIIA) in the erythrocytes in all individuals (1-3 aggregates/cell, 1-3 µm diameter). By systematically reanalyzing blood smears from a cohort of patients with 19 different forms of IPD, we found similar NMMIIA aggregates in the red blood cells only in subjects with GFI1B-related thrombocytopenia (GFI1B-RT), the other major IPD featured by dyserythropoiesis. CONCLUSION: Aggregates of NMMIIA in the erythrocytes associate with GATA1-RT and GFI1B-RT and can facilitate their diagnosis on blood smears. This previously unreported finding might represent a novel marker of dyserythropoiesis assessable in peripheral blood.


Assuntos
Anemia , Fator de Transcrição GATA1 , Miosina não Muscular Tipo IIA , Proteínas Proto-Oncogênicas , Proteínas Repressoras , Trombocitopenia , Humanos , Plaquetas/metabolismo , Eritrócitos , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética
17.
Eur J Hum Genet ; 32(7): 858-863, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38778080

RESUMO

The ABC and ACMG variant classification systems were compared by asking mainly European clinical laboratories to classify variants in 10 challenging cases using both systems, and to state if the variant in question would be reported as a relevant result or not as a measure of clinical utility. In contrast to the ABC system, the ACMG system was not made to guide variant reporting but to determine the likelihood of pathogenicity. Nevertheless, this comparison is justified since the ACMG class determines variant reporting in many laboratories. Forty-three laboratories participated in the survey. In seven cases, the classification system used did not influence the reporting likelihood when variants labeled as "maybe report" after ACMG-based classification were included. In three cases of population frequent but disease-associated variants, there was a difference in favor of reporting after ABC classification. A possible reason is that ABC step C (standard variant comments) allows a variant to be reported in one clinical setting but not another, e.g., based on Bayesian-based likelihood calculation of clinical relevance. Finally, the selection of ACMG criteria was compared between 36 laboratories. When excluding criteria used by less than four laboratories (<10%), the average concordance rate was 46%. Taken together, ABC-based classification is more clear-cut than ACMG-based classification since molecular and clinical information is handled separately, and variant reporting can be adapted to the clinical question and phenotype. Furthermore, variants do not get a clinically inappropriate label, like pathogenic when not pathogenic in a clinical context, or variant of unknown significance when the significance is known.


Assuntos
Variação Genética , Humanos , Testes Genéticos/normas , Testes Genéticos/métodos
18.
Eur J Microbiol Immunol (Bp) ; 13(3): 83-87, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37856196

RESUMO

Infections caused by Staphylococcus aureus are currently a worldwide threat affecting millions of individuals. The pathogenicity of S. aureus is associated with numerous virulence factors, including cell surface proteins, polysaccharides, and secreted toxins. The pore-forming α-hemolysin, known as α-toxin, is produced by nearly all virulent strains of S. aureus and is implicated in several diseases including skin and soft tissue infections, atopic dermatitis, and pneumonia. There are currently no vaccines available for the prevention of S. aureus infections and the efficacy of available antibiotics has been fading. In this study we examined the mode of antihemolytic activity of theaflavin-3,3'-digallate against α-hemolysin of methicillin-resistant S. aureus by molecular docking using AutoDock Vina as the molecular docking tool. The theaflavin-3,3'-digallate docked the molecular sequence of the Hla (PDB ID:7ahl). The scores of the top 10 binding modes obtained were between -9.0 and -8.5 kcal mol-1, and the best binding mode was -9.0 kcal mol-1. Direct binding sites of theaflavin-3,3'-digallate to the "stem" domain of Hla were revealed which primarily targeted of the residues Met113, Thr117, Asn139. The disclosure of this potential binding mode warrants further clinical evaluation of theaflavin-3,3'-digallate as an anti-hemolytic compound in order to practically validate our results.

19.
PLoS One ; 18(8): e0290904, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37651426

RESUMO

The ongoing rise in antibiotic resistance, and a waning of the introduction of new antibiotics, has resulted in limited treatment options for bacterial infections, including these caused by methicillin-resistant Staphylococcus aureus, leaving the world in a post-antibiotic era. Here, we set out to examine mechanisms by which theaflavin 3,3'-digallate (TF3) might act as an anti-hemolytic compound. In the presented study, we found that TF3 has weak bacteriostatic and bactericidal effects on Staphylococcus aureus, and strong inhibitory effect towards the hemolytic activity of its α-hemolysin (Hla) including its production and secretion. A supportive SPR assay reinforced these results and further revealed binding of TF3 to Hla with KD = 4.57×10-5 M. Interestingly, TF3 was also able to protect human primary keratinocytes from Hla-induced cell death, being at the same time non-toxic for them. Further analysis of TF3 properties revealed that TF3 blocked Hla-prompting immune reaction by inhibiting production and secretion of IL1ß, IL6, and TNFα in vitro and in vivo, through affecting NFκB activity. Additionally, we observed that TF3 also markedly attenuated S. aureus-induced barrier disruption, by inhibiting Hla-triggered E-cadherin and ZO-1 impairment. Overall, by blocking activity of Hla, TF3 subsequently subdued the inflammation and protected the epithelial barrier, which is considered as beneficial to relieving skin injury.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Proteínas Hemolisinas , Infecções Estafilocócicas/tratamento farmacológico , Antibacterianos/farmacologia
20.
Eur J Microbiol Immunol (Bp) ; 13(1): 6-14, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37256738

RESUMO

SARS-CoV-2 infection still poses health threats especially to older and immunocompromised individuals. New emerging variants of SARS-CoV-2, including Omicron and Arcturus, have been challenging the effectiveness of humoral immunity resulting from repeated vaccination and infection. With recent study implying a wave of new mutants in vaccinated people making them more susceptible to the newest variants and fueling a rapid viral evolution, there is a need for alternative or adjunct approaches against coronavirus infections other than vaccines. Our earlier work indicated that a specific combination of micronutrients and phytochemicals can inhibit key infection mechanisms shared by SARS-CoV-2 and its variants in vitro. Here we demonstrate in vivo that an intake of this micronutrient combination before and during infection of mice with engineered SARS-CoV-2 virions and HCoV-229E virus results in a significant decrease in viral load and level of spike protein in the lungs. This was accompanied by decreased inflammatory response, including TNFα, IL1ß, ILα, and IL17. These and our earlier results confirm that by targeting multiple mechanisms simultaneously by a combination treatment we can effectively and safely challenge SARS-CoV-2 and HCoV-229E virus. If clinically confirmed, such an approach could complement already in-use preventive and therapeutic strategies against coronavirus infections.

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