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1.
J Chem Phys ; 158(8): 084501, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36859089

RESUMO

Three-dimensional crystalline frameworks with nanoscale periodicity are valuable for many emerging technologies, from nanophotonics to nanomedicine. DNA nanotechnology has emerged as a prime route for constructing these materials, with most approaches taking advantage of the structural rigidity and bond directionality programmable for DNA building blocks. Recently, we have introduced an alternative strategy reliant on flexible, amphiphilic DNA junctions dubbed C-stars, whose ability to crystallize is modulated by design parameters, such as nanostructure topology, conformation, rigidity, and size. While C-stars have been shown to form ordered phases with controllable lattice parameter, response to stimuli, and embedded functionalities, much of their vast design space remains unexplored. Here, we investigate the effect of changing the chemical nature of the hydrophobic modifications and the structure of the DNA motifs in the vicinity of these moieties. While similar design variations should strongly alter key properties of the hydrophobic interactions between C-stars, such as strength and valency, only limited differences in self-assembly behavior are observed. This finding suggests that long-range order in C-star crystals is likely imposed by structural features of the building block itself rather than the specific characteristics of the hydrophobic tags. Nonetheless, we find that altering the hydrophobic regions influences the ability of C-star crystals to uptake hydrophobic molecular cargoes, which we exemplify by studying the encapsulation of antibiotic penicillin V. Besides advancing our understanding of the principles governing the self-assembly of amphiphilic DNA building blocks, our observations thus open up new routes to chemically program the materials without affecting their structure.


Assuntos
Nanoestruturas , Cristalização , Nanotecnologia , Antibacterianos , DNA
2.
J Appl Clin Med Phys ; 24(8): e13993, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37071500

RESUMO

PURPOSE: To determine the effect of megavoltage (MV) scatter on the accuracy of markerless tumor tracking (MTT) for lung tumors using dual energy (DE) imaging and to consider a post-processing technique to mitigate the effects of MV scatter on DE-MTT. METHODS: A Varian TrueBeam linac was used to acquire a series of interleaved 60/120 kVp images of a motion phantom with simulated tumors (10 and 15 mm diameter). Two sets of consecutive high/low energy projections were acquired, with and without MV beam delivery. The MV field sizes (FS) ranged from 2 × 2 cm2 -6 × 6 cm2 in steps of 1 × 1 cm2 . Weighted logarithmic subtraction was performed on sequential images to produce soft-tissue images for kV only (DEkV ) and kV with MV beam on (DEkV+MV ). Wavelet and fast Fourier transformation filtering (wavelet-FFT) was used to remove stripe noise introduced by MV scatter in the DE images ( DE kV + MV Corr ${\rm{DE}}_{{\rm{kV}} + {\rm{MV}}}^{{\rm{Corr}}}$ ). A template-based matching algorithm was then used to track the target on DEkV, DEkV+MV , and DE kV + MV Corr ${\rm{DE}}_{{\rm{kV}} + {\rm{MV}}}^{{\rm{Corr}}}$ images. Tracking accuracy was evaluated using the tracking success rate (TSR) and mean absolute error (MAE). RESULTS: For the 10 and 15 mm targets, the TSR for DEkV images was 98.7% and 100%, and MAE was 0.53 and 0.42 mm, respectively. For the 10 mm target, the TSR, including the effects of MV scatter, ranged from 86.5% (2 × 2 cm2 ) to 69.4% (6 × 6 cm2 ), while the MAE ranged from 2.05 mm to 4.04 mm. The application of wavelet-FFT algorithm to remove stripe noise ( DE kV + MV Corr ${\rm{DE}}_{{\rm{kV}} + {\rm{MV}}}^{{\rm{Corr}}}$ ) resulted in TSR values of 96.9% (2 × 2 cm2 ) to 93.4% (6 × 6 cm2 ) and subsequent MAE values were 0.89 mm to 1.37 mm. Similar trends were observed for the 15 mm target. CONCLUSION: MV scatter significantly impacts the tracking accuracy of lung tumors using DE images. Wavelet-FFT filtering can improve the accuracy of DE-MTT during treatment.


Assuntos
Neoplasias Pulmonares , Humanos , Raios X , Radiografia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Imagens de Fantasmas , Algoritmos
3.
Int J Mol Sci ; 24(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36901702

RESUMO

Recurrent implantation failure (RIF) is a global health issue affecting a significant number of infertile women who undergo in vitro fertilization (IVF) cycles. Extensive vasculogenesis and angiogenesis occur in both maternal and fetal placental tissues, and vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) family molecules and their receptors are potent angiogenic mediators in the placenta. Five single nucleotide polymorphisms (SNPs) in the genes encoding angiogenesis-related factors were selected and genotyped in 247 women who had undergone the ART procedure and 120 healthy controls. Genotyping was conducted by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A variant of the kinase insertion domain receptor (KDR) gene (rs2071559) was associated with an increased risk of infertility after adjusting for age and BMI (OR = 0.64; 95% CI: 0.45-0.91, p = 0.013 in a log-additive model). Vascular endothelial growth factor A (VEGFA) rs699947 was associated with an increased risk of recurrent implantation failures under a dominant (OR = 2.34; 95% CI: 1.11-4.94, padj. = 0.022) and a log-additive model (OR = 0.65; 95% CI 0.43-0.99, padj. = 0.038). Variants of the KDR gene (rs1870377, rs2071559) in the whole group were in linkage equilibrium (D' = 0.25, r2 = 0.025). Gene-gene interaction analysis showed the strongest interactions between the KDR gene SNPs rs2071559-rs1870377 (p = 0.004) and KDR rs1870377-VEGFA rs699947 (p = 0.030). Our study revealed that the KDR gene rs2071559 variant may be associated with infertility and rs699947 VEGFA with an increased risk of recurrent implantation failures in infertile ART treated Polish women.


Assuntos
Infertilidade Feminina , Fator A de Crescimento do Endotélio Vascular , Feminino , Humanos , Gravidez , Estudos de Casos e Controles , Genótipo , Placenta , Polimorfismo de Nucleotídeo Único , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
4.
J Am Chem Soc ; 144(38): 17468-17476, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36103297

RESUMO

Biological cells display complex internal architectures with distinct micro environments that establish the chemical heterogeneity needed to sustain cellular functions. The continued efforts to create advanced cell mimics, namely, artificial cells, demands strategies for constructing similarly heterogeneous structures with localized functionalities. Here, we introduce a platform for constructing membraneless artificial cells from the self-assembly of synthetic DNA nanostructures in which internal domains can be established thanks to prescribed reaction-diffusion waves. The method, rationalized through numerical modeling, enables the formation of up to five distinct concentric environments in which functional moieties can be localized. As a proof-of-concept, we apply this platform to build DNA-based artificial cells in which a prototypical nucleus synthesizes fluorescent RNA aptamers that then accumulate in a surrounding storage shell, thus demonstrating the spatial segregation of functionalities reminiscent of that observed in biological cells.


Assuntos
Aptâmeros de Nucleotídeos , Células Artificiais , Nanoestruturas , DNA/química , Difusão , Nanoestruturas/química
5.
J Appl Clin Med Phys ; 23(12): e13821, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36350280

RESUMO

PURPOSE: To evaluate the impact of various noise reduction algorithms and template matching parameters on the accuracy of markerless tumor tracking (MTT) using dual-energy (DE) imaging. METHODS: A Varian TrueBeam linear accelerator was used to acquire a series of alternating 60 and 120 kVp images (over a 180° arc) using fast kV switching, on five early-stage lung cancer patients. Subsequently, DE logarithmic weighted subtraction was performed offline on sequential images to remove bone. Various noise reduction techniques-simple smoothing, anticorrelated noise reduction (ACNR), noise clipping (NC), and NC-ACNR-were applied to the resultant DE images. Separately, tumor templates were generated from the individual planning CT scans, and band-pass parameter settings for template matching were varied. Template tracking was performed for each combination of noise reduction techniques and templates (based on band-pass filter settings). The tracking success rate (TSR), root mean square error (RMSE), and missing frames (percent unable to track) were evaluated against the estimated ground truth, which was obtained using Bayesian inference. RESULTS: DE-ACNR, combined with template band-pass filter settings of σlow  = 0.4 mm and σhigh  = 1.6 mm resulted in the highest TSR (87.5%), RMSE (1.40 mm), and a reasonable amount of missing frames (3.1%). In comparison to unprocessed DE images, with optimized band-pass filter settings of σlow  = 0.6 mm and σhigh  = 1.2 mm, the TSR, RMSE, and missing frames were 85.3%, 1.62 mm, and 2.7%, respectively. Optimized band-pass filter settings resulted in improved TSR values and a lower missing frame rate for both unprocessed DE and DE-ACNR as compared to the use previously published band-pass parameters based on single energy kV images. CONCLUSION: Noise reduction strategies combined with the optimal selection of band-pass filter parameters can improve the accuracy and TSR of MTT for lung tumors when using DE imaging.


Assuntos
Neoplasias Pulmonares , Humanos , Teorema de Bayes , Imagens de Fantasmas , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão , Algoritmos
6.
Nano Lett ; 21(7): 2800-2808, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33733783

RESUMO

Cell membranes regulate the distribution of biological machinery between phase-separated lipid domains to facilitate key processes including signaling and transport, which are among the life-like functionalities that bottom-up synthetic biology aims to replicate in artificial-cellular systems. Here, we introduce a modular approach to program partitioning of amphiphilic DNA nanostructures in coexisting lipid domains. Exploiting the tendency of different hydrophobic "anchors" to enrich different phases, we modulate the lateral distribution of our devices by rationally combining hydrophobes and by changing nanostructure size and topology. We demonstrate the functionality of our strategy with a bioinspired DNA architecture, which dynamically undergoes ligand-induced reconfiguration to mediate cargo transport between domains via lateral redistribution. Our findings pave the way to next-generation biomimetic platforms for sensing, transduction, and communication in synthetic cellular systems.


Assuntos
DNA , Nanoestruturas , Fenômenos Biofísicos , Membrana Celular , Bicamadas Lipídicas , Lipídeos
7.
Knee Surg Sports Traumatol Arthrosc ; 29(6): 1983-1989, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32980886

RESUMO

PURPOSE: In this study, the functional mid-term outcomes of the modified Grammont and Langenskiöld technique was assessed in skeletally immature patients with habitual patellar dislocation, with emphasis on knee function, pain, and other possible post-surgical complications. This is the first study concerning the application of the modified Grammont and Langenskiöld technique in habitual patellar dislocations. METHODS: This retrospective cohort study considered 10 patients (15 knees), ranging from 7 to 11 years old, who underwent the modified Grammont and Langenskiold procedure between 2015 and 2018. History of dislocation, patellar stability and range of motion (ROM) were analysed. To assess functional improvement and knee pain, the Kujala Anterior Knee Pain Scale and KOOS-Child Knee Survey were used before and after surgical treatment. RESULTS: No history of dislocation was noted after surgical treatment. All 15 knees showed full ROM. There were no signs of genu recurvatum and no length discrepancies were found. The subjective assessment revealed significant improvement in the scores of the KOOS-Child questionnaire in all five sections (p < 0.001), as well as in The Kujala Anterior Knee Pain Scale (p = 0.001). CONCLUSION: The modified Grammont and Langenskiöld technique yields remarkable results in terms of knee stability and knee function, while decreasing recurrence risk and intensity of pain in patients with challenging cases of patellofemoral joint dislocation. This surgical technique is most effective in cases where the patella remains dislocated continuously; however, it may also be used in immature patients with recurrent instability. LEVEL OF EVIDENCE: IV.


Assuntos
Artroplastia/métodos , Luxação Patelar/cirurgia , Articulação Patelofemoral/cirurgia , Artralgia/etiologia , Artralgia/fisiopatologia , Criança , Feminino , Humanos , Masculino , Luxação Patelar/complicações , Luxação Patelar/fisiopatologia , Articulação Patelofemoral/fisiopatologia , Amplitude de Movimento Articular , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
8.
Bioinformatics ; 34(15): 2590-2597, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29547986

RESUMO

Motivation: Automated selection of signals in protein NMR spectra, known as peak picking, has been studied for over 20 years, nevertheless existing peak picking methods are still largely deficient. Accurate and precise automated peak picking would accelerate the structure calculation, and analysis of dynamics and interactions of macromolecules. Recent advancement in handling big data, together with an outburst of machine learning techniques, offer an opportunity to tackle the peak picking problem substantially faster than manual picking and on par with human accuracy. In particular, deep learning has proven to systematically achieve human-level performance in various recognition tasks, and thus emerges as an ideal tool to address automated identification of NMR signals. Results: We have applied a convolutional neural network for visual analysis of multidimensional NMR spectra. A comprehensive test on 31 manually annotated spectra has demonstrated top-tier average precision (AP) of 0.9596, 0.9058 and 0.8271 for backbone, side-chain and NOESY spectra, respectively. Furthermore, a combination of extracted peak lists with automated assignment routine, FLYA, outperformed other methods, including the manual one, and led to correct resonance assignment at the levels of 90.40%, 89.90% and 90.20% for three benchmark proteins. Availability and implementation: The proposed model is a part of a Dumpling software (platform for protein NMR data analysis), and is available at https://dumpling.bio/. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Aprendizado Profundo , Ressonância Magnética Nuclear Biomolecular/métodos , Proteínas/química , Software , Substâncias Macromoleculares/química
9.
Pharmacogenomics J ; 19(4): 358-367, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30293984

RESUMO

Biological therapy with anti-tumor necrosis factor-α (anti-TNF-α) monoclonal antibodies significantly increased the effectiveness of autoimmune disease treatment compared with conventional medicines. However, anti-TNF-α drugs are relatively expensive and a response to the therapy is reported in only 60-70% of patients. Moreover, in up to 5% of patients adverse drug reactions occur. The various effects of biological treatment may be a potential consequence of interindividual genetic variability. Only a few studies have been conducted in this field and which refer to single gene loci. Our aim was to design and optimize a methodology for a broader application of pharmacogenetic studies in patients undergoing anti-TNF-α treatment. Based on the current knowledge, we selected 16 candidate genes: TNFRSF1A, TNFRSF1B, ADAM17, CASP9, FCGR3A, LTA, TNF, FAS, IL1B, IL17A, IL6, MMP1, MMP3, S100A8, S100A9, and S100A12, which are potentially involved in the response to anti-TNF-α therapy. As a research model, three DNA samples from Crohn's disease (CD) patients were used. Targeted genomic regions were amplified in 23 long-range (LR) PCR reactions and after enzymatic fragmentation amplicon libraries were prepared and analyzed by next-generation sequencing (NGS). Our results indicated 592 sequence variations located in all fragments with coverage range of 5-1089. We demonstrate a highly sensitive, flexible, rapid, and economical approach to the pharmacogenetic investigation of anti-TNF-α therapy using amplicon libraries and NGS technology.


Assuntos
Anticorpos Monoclonais/farmacologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Testes Farmacogenômicos/métodos , Reação em Cadeia da Polimerase/métodos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Antineoplásicos/farmacologia , Humanos
10.
J Biomol NMR ; 71(1): 11-18, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29777498

RESUMO

Analysis of structure, function and interactions of proteins by NMR spectroscopy usually requires the assignment of resonances to the corresponding nuclei in protein. This task, although automated by methods such as FLYA or PINE, is still frequently performed manually. To facilitate the manual sequence-specific chemical shift assignment of complex proteins, we propose a method based on Dirichlet process mixture model (DPMM) that performs automated matching of groups of signals observed in NMR spectra to corresponding nuclei in protein sequence. The model has been extensively tested on 80 proteins retrieved from the BMRB database and has shown superior performance to the reference method.


Assuntos
Modelos Teóricos , Ressonância Magnética Nuclear Biomolecular/métodos , Proteínas/química , Sequência de Aminoácidos , Bases de Dados de Proteínas
11.
Crit Rev Food Sci Nutr ; 58(18): 3130-3140, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28718657

RESUMO

It is well known that consumption of Brassica vegetables has beneficial effect on human's health. The greatest interest is focused on glucosinolates and their hydrolysis products isothiocyanates, due to their potential as cancer preventing compounds. Brassica vegetables are also rich in flavor compounds belonging to many chemical groups. The main sensory sensation related to these vegetable is their characteristic sharp and bitter taste, and unique aroma. Because of these features this group of vegetables is often rejected by consumers. Interestingly, for some people unpleasant sensations are not perceived, suggesting a potential role of inter-individual variability in bitter taste perception and sensibility. Receptors responsible for bitter sensation with the emphasis on Brassica are reviewed, as well as genetic predisposition for bitterness perception by consumers. Also the role of glucosinolates and isothiocyanates as compounds responsible for bitter taste is discussed based on data from the field of food science and molecular biology. Isothiocyanates are shown in broaded context of flavor compounds also contributing to the aroma of Brassica vegetables.


Assuntos
Brassica/química , Glucosinolatos/análise , Isotiocianatos/análise , Percepção Gustatória/genética , Paladar/fisiologia , Anticarcinógenos , Comportamento do Consumidor , Preferências Alimentares , Glucosinolatos/metabolismo , Glicosídeo Hidrolases/metabolismo , Humanos , Isotiocianatos/metabolismo , Odorantes/análise , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/fisiologia , Receptores Odorantes/genética , Receptores Odorantes/fisiologia , Paladar/efeitos dos fármacos , Paladar/genética , Percepção Gustatória/efeitos dos fármacos , Percepção Gustatória/fisiologia , Canais de Potencial de Receptor Transitório/genética , Canais de Potencial de Receptor Transitório/fisiologia
12.
Bioinformatics ; 31(18): 2981-8, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25995228

RESUMO

MOTIVATION: A detailed analysis of multidimensional NMR spectra of macromolecules requires the identification of individual resonances (peaks). This task can be tedious and time-consuming and often requires support by experienced users. Automated peak picking algorithms were introduced more than 25 years ago, but there are still major deficiencies/flaws that often prevent complete and error free peak picking of biological macromolecule spectra. The major challenges of automated peak picking algorithms is both the distinction of artifacts from real peaks particularly from those with irregular shapes and also picking peaks in spectral regions with overlapping resonances which are very hard to resolve by existing computer algorithms. In both of these cases a visual inspection approach could be more effective than a 'blind' algorithm. RESULTS: We present a novel approach using computer vision (CV) methodology which could be better adapted to the problem of peak recognition. After suitable 'training' we successfully applied the CV algorithm to spectra of medium-sized soluble proteins up to molecular weights of 26 kDa and to a 130 kDa complex of a tetrameric membrane protein in detergent micelles. Our CV approach outperforms commonly used programs. With suitable training datasets the application of the presented method can be extended to automated peak picking in multidimensional spectra of nucleic acids or carbohydrates and adapted to solid-state NMR spectra. AVAILABILITY AND IMPLEMENTATION: CV-Peak Picker is available upon request from the authors. CONTACT: gsw@mol.biol.ethz.ch; michal.walczak@mol.biol.ethz.ch; adam.gonczarek@pwr.edu.pl SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Reconhecimento Visual de Modelos , Proteínas/química , Humanos
13.
Med Sci Monit ; 21: 181-94, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25598197

RESUMO

BACKGROUND: No research group has ever investigated the level of kinesiophobia in a well defined group of preoperative patients treated due to cervical discopathy and degenerative spine disease, confirmed by X-ray and magnetic resonance imaging (MRI) examinations. We aimed to investigate the degree of kinesiophobia and the differences in pain-related and psychosocial characteristics between patients with high and low levels of kinesiophobia, in relation to factors commonly associated with neck pain. MATERIAL/METHODS: Sixty-five consecutive patients with cervical discopathy and coexisting degenerative changes were assessed pre-surgically. The mean pain duration was 31.7 SD 34.0 months. Patients completed the Polish versions of the Tampa Scale for Kinesiophobia (TSK-PL) on 2 occasions, and the following once: Neck Disability Index (NDI-PL), State-Trait Anxiety Inventory (STAI-PL), Coping Strategies Questionnaire (CSQ-PL), and the Visual Analogue Scale (VAS-PL). RESULTS: A high level of kinesiophobia was indicated in 81.5% and 87.7% of patients in first and second completion, respectively. Patients with high and low kinesiophobia differ in regards to the recreation section of NDI-PL (p=0.012), gender (p=0.043), and sports activity (p=0.024). Correlations were identified between TSK-PL and marital status (p=0.023) and sports activity (p=0.024). CONCLUSIONS: Kinesiophobia levels are higher in patients with chronic cervical pain before surgical treatment. Fear of movement tends to be higher in women and among patients avoiding sports recreation before surgical treatment. Although sports activity and socio-demographic data are predictors of kinesiophobia, psychological, pain-related, and clinical data are not. These findings should be considered when planning rehabilitation after surgical treatment of cervical discopathy and coexisting degenerative changes.


Assuntos
Ansiedade/diagnóstico , Dor Crônica/diagnóstico , Cervicalgia/diagnóstico , Esportes , Adaptação Psicológica , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Dor , Medição da Dor , Período Pré-Operatório , Psicometria , Classe Social , Inquéritos e Questionários , Resultado do Tratamento , Raios X
14.
Angew Chem Int Ed Engl ; 54(24): 7096-100, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25924827

RESUMO

Posttranslational modifications (PTMs) are an integral part of the majority of proteins. The characterization of structure and function of PTMs can be very challenging especially for glycans. Existing methods to analyze PTMs require complicated sample preparations and suffer from missing certain modifications, the inability to identify linkage types and thus chemical structure. We present a direct, robust, and simple NMR spectroscopy method for the detection and identification of PTMs in proteins. No isotope labeling is required, nor does the molecular weight of the studied protein limit the application. The method can directly detect modifications on intact proteins without sophisticated sample preparation. This approach is well suited for diagnostics of proteins derived from native organisms and for the quality control of biotechnologically produced therapeutic proteins.


Assuntos
Proteínas/química , Sequência de Carboidratos , Glicosilação , Ressonância Magnética Nuclear Biomolecular , Polissacarídeos/análise , Polissacarídeos/química , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo
15.
Nat Chem Biol ; 13(5): 452-453, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28406888

Assuntos
Proteólise
16.
Angew Chem Int Ed Engl ; 53(5): 1320-3, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24356903

RESUMO

Ste5 is a scaffold protein that controls the pheromone response of the MAP-kinase cascade in yeast cells. Upon pheromone stimulation, Ste5 (through its RING-H2 domain) interacts with the ß and γ subunits of an activated heterodimeric G protein and promotes activation of the MAP-kinase cascade. With structural and biophysical studies, we show that the Ste5 RING-H2 domain exists as a molten globule under native buffer conditions, in yeast extracts, and even in denaturing conditions containing urea (7 M). Furthermore, it exhibits high thermal stability in native conditions. Binding of the Ste5 RING-H2 domain to the physiological Gß/γ (Ste4/Ste18) ligand is accompanied by a conformational transition into a better folded, more globular structure. This study reveals novel insights into the folding mechanism and recruitment of binding partners by the Ste5 RING-H2 domain. We speculate that many RING domains may share a similar mechanism of substrate recognition and molten-globule-like character.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas de Saccharomyces cerevisiae/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Subunidades beta da Proteína de Ligação ao GTP/química , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/química , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Mercaptoetanol/química , Ressonância Magnética Nuclear Biomolecular , Dobramento de Proteína , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Cloreto de Sódio/química , Temperatura , Ureia/química
17.
J Appl Genet ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238614

RESUMO

Placental angiogenesis is a pivotal process for feto-maternal circulation and ensures efficient development of the placenta throughout pregnancy. Many factors during in vitro fertilization and embryo transfer procedures may affect placental gene expression and fetus development. The present study aimed to identify differences in angiogenesis-related gene (VEGFA, FGF2, FLT1, and KDR) expression profiles in placentas after assisted reproductive technology fertilization and natural conception in healthy women. In a case-control study, term placentas were collected from Caucasian women after assisted reproductive technology fertilization (N = 20) and after natural conception in women with uncomplicated pregnancy (N = 9). The mRNA expression in placentas was examined for VEGFA, FGF2, FLT1, and KDR genes by real-time quantitative polymerase chain reaction (RT-qPCR). Group stratification was performed for comparison of investigated genes between the type of embryo transferred (fresh/frozen), place of tissue donation (center/margin), and newborns' gender (male/female). In the ART placentas, significant down-regulation of VEGFA gene (p = 0.016) and up-regulation of FLT1 (p = 0.026) and KDR (p < 0.001) gene receptors were observed. Genes encoding VEGFA receptors were up-regulated in both fresh (ET) and frozen (FET) embryo transfer groups compared to controls. For the FLT1 gene, a statistically significant difference was observed between the frozen embryo transfer group and the controls (p = 0.032). Relative expression of KDR was significantly higher for both embryo transfer groups compared to controls (p < 0.001) and between ET and FET (p = 0.002). No statistically significant differences were observed between placental expression in different places of tissue donation and newborns' gender. We observed differences in the placental expression of VEGFA and its receptors FLT1 and KDR in pregnancies after assisted reproductive technology compared to naturally conceived pregnancies. More research is needed to clarify these alterations that may affect placental development and fetal health.

18.
Gene ; 893: 147909, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37858746

RESUMO

INTRODUCTION: Several studies showed the correlation of retinol-binding protein 4 (RBP4) with increased cardiovascular risk - including higher values of carotid intima-media thickness (cIMT) - particularly in individuals with obesity. OBJECTIVES: Our study aimed to investigate the impact of rs10882273; rs3758538; rs3758539, and rs7094671 RBP4 gene variants on RBP4 serum concentrations as well as cIMT values (a marker of subclinical atherosclerosis) among female patients with obesity. PATIENTS AND METHODS: We recruited 74 women with obesity and 24 women without obesity as a study and control group, respectively. The genotypic and allelic frequencies of RBP4 gene variants were evaluated for associations with serum RBP4 and cIMT. RESULTS: The median serum RBP4 concentrations were 20.30 µg/mL and 19.80 µg/mL in the patients and control group, respectively (p = 0.740). No significant differences were seen in cIMT values between the two studied groups (0.60 [0.50-1.00] vs. 0.60 ± 0.10 in the patient and control group, respectively); however, the results were close to reaching significance (p = 0.071), similar as in observed association of the minor haplotype AA for rs7084671 and rs375839 with female obesity (p = 0.0559). The correlation analysis showed no significant differences between RBP4 gene variants with serum RBP4 and cIMT. CONCLUSIONS: According to our knowledge, this is the first study investigating the association between RBP4 gene variants and serum RBP4 and cIMT among Polish female patients with obesity. However, our results show that genetic variants rs10882273, rs3758538, rs3758539, and rs7094671 of the RBP4 gene are not associated with RBP4 serum concentrations or cIMT values among women with obesity.


Assuntos
Aterosclerose , Espessura Intima-Media Carotídea , Humanos , Feminino , Fatores de Risco , Obesidade/genética , Obesidade/complicações , Aterosclerose/complicações , Frequência do Gene , Proteínas Plasmáticas de Ligação ao Retinol/genética
19.
Wiad Lek ; 66(2 Pt 2): 206-9, 2013.
Artigo em Polonês | MEDLINE | ID: mdl-25775819

RESUMO

We present case report of 51-year-old female patient admitted to surgery ward because of presence of pyogenic discharge in perianal region since 7 months. Eighteen months earlierthe patient underwent stress urinary incontinence procedure with use of TVT synthetic implant. Diagnosis of wast, bilateral, composite vagino-perianal fistule was made. After carrying out four operations with two stage sling removal final postfistule wound healing was obtained.


Assuntos
Remoção de Dispositivo , Polipropilenos/efeitos adversos , Slings Suburetrais/efeitos adversos , Incontinência Urinária por Estresse/cirurgia , Infecções Urinárias/etiologia , Infecções Urinárias/cirurgia , Infecções Bacterianas/etiologia , Infecções Bacterianas/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Urológicos/métodos
20.
J Pediatr Orthop B ; 32(3): 227-229, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580383

RESUMO

The work aims to revise the current views on the effectiveness of Dega's pelvic osteotomy in preventing femoral head deformity in the course of Perthes' disease in patients with late symptoms >8 years of age and withsignificant changes in the radiographic image (Catterall III/IV or Herring B, B/C, C). We did a literature review. Four articles from six found in 'PubMed' which combine Dega acetabuloplasty and Perthes' disease words were fully read and analyzed. Kamegaya (2018), with a 9.5-year follow-up period, described differences comparing the group treated with femoral varus osteotomy with the group that was treated with a combined Dega acetabuloplasty and femoral varus osteotomy. A series of papers by Napiontek from 2004, with an average 8-year follow-up, also describes satisfactory results after Dega's osteotomy, with 27 hips in groups I/II according to Stulberg. Another paper in the series, which analyzed operatively and non-operatively treated patients, shows no differences in the period of time of Perthes disease treatment between the analyzed groups. The last paper in the series from 2001, describes 10 patients treated primarily due to hip dysplasia, who was diagnosed with Perthes disease. Five of them underwent Dega acetabuloplasty obtaining a Stulberg score of I/II in the long-term follow-up. We think it seems reasonable to return to the treatment planning of Perthes' disease using Dega acetabuloplasty as a method to improve the hip congruence in late-diagnosed and advanced forms of the disease.


Assuntos
Acetabuloplastia , Doença de Legg-Calve-Perthes , Humanos , Doença de Legg-Calve-Perthes/diagnóstico por imagem , Doença de Legg-Calve-Perthes/cirurgia , Articulação do Quadril/cirurgia , Resultado do Tratamento , Osteotomia/métodos , Seguimentos
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