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1.
Methods Mol Biol ; 2825: 309-331, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38913318

RESUMO

Across eukaryotes, genome stability is essential for normal cell function, physiology, and species survival. Aberrant expression of key genes or exposure to genotoxic agents can have detrimental effects on genome stability and contribute to the development of various diseases, including cancer. Chromosome instability (CIN), or ongoing changes in chromosome complements, is a frequent form of genome instability observed in cancer and is a driver of genetic and cell-to-cell heterogeneity that can be rapidly detected and quantitatively assessed using surrogate markers of CIN. For example, single cell quantitative imaging microscopy (QuantIM) can be used to simultaneously identify changes in nuclear areas and micronucleus formation. While changes in nuclear areas are often associated with large-scale changes in chromosome complements (i.e., ploidy), micronuclei are small extra-nuclear bodies found outside the primary nucleus that have previously been employed as a measure of genotoxicity of test compounds. Here, we present a facile QuantIM approach that allows for the rapid assessment and quantification of CIN associated phenotypes and genotoxicity. First, we provide protocols to optimize and execute CIN and genotoxicity assays. Secondly, we present the critical imaging settings, optimization steps, downstream statistical analyses, and data visualization strategies employed to obtain high quality and robust data. These approaches can be easily applied to assess the prevalence of CIN associated phenotypes and genotoxic stress for a myriad of experimental and clinical contexts ranging from direct tests to large-scale screens of various genetic contexts (i.e., aberrant gene expression) or chemical compounds. In summary, this QuantIM approach facilitates the identification of novel CIN genes and/or genotoxic agents that will provide greater insight into the aberrant genes and pathways underlying CIN and genotoxicity.


Assuntos
Instabilidade Cromossômica , Dano ao DNA , Análise de Célula Única , Análise de Célula Única/métodos , Humanos , Microscopia/métodos , Testes de Mutagenicidade/métodos , Núcleo Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , Mutagênicos/toxicidade , Testes para Micronúcleos/métodos
2.
Carbohydr Polym ; 339: 122189, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823897

RESUMO

Cranberry waste contains potentially valuable components, such as proanthocyanidins, flavanols, and xyloglucan. Highly-purified xyloglucan (XG) from cranberries were studied through steady and oscillatory shear rheology at various concentrations and temperatures. At room temperature, an apparent yield stress is observed and the storage modulus exceeds the loss modulus ( [Formula: see text] ) for concentrations of 0.5 wt% and higher, indicating that the XG solution has formed a physical hydrogel. Thermoresponsive gelation is observed with a five-order of magnitude increase in shear moduli as it undergoes a weak to strong gel transition around 52 °C. The gelation time was 5 min with an observed storage moduli up to 3500 Pa. Cranberry-based XG exhibits thermoresponsive behavior at concentrations as low as 0.1 wt% (w/v), which is significantly lower than prior gelation studies of XG from other sources. The formation of a weak gel at room temperature and large storage moduli observed at room temperature is likely associated with the low level of impurities and small amount of galactose present in the XG chains.

3.
Quant Plant Biol ; 5: e5, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774130

RESUMO

Plant growth requires the integration of internal and external cues, perceived and transduced into a developmental programme of cell division, elongation and wall thickening. Mechanical forces contribute to this regulation, and thigmomorphogenesis typically includes reducing stem height, increasing stem diameter, and a canonical transcriptomic response. We present data on a bZIP transcription factor involved in this process in grasses. Brachypodium distachyon SECONDARY WALL INTERACTING bZIP (SWIZ) protein translocated into the nucleus following mechanostimulation. Classical touch-responsive genes were upregulated in B. distachyon roots following touch, including significant induction of the glycoside hydrolase 17 family, which may be unique to grass thigmomorphogenesis. SWIZ protein binding to an E-box variant in exons and introns was associated with immediate activation followed by repression of gene expression. SWIZ overexpression resulted in plants with reduced stem and root elongation. These data further define plant touch-responsive transcriptomics and physiology, offering insights into grass mechanotranduction dynamics.

4.
J Occup Environ Med ; 66(4): 305-309, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588071

RESUMO

OBJECTIVE: The purpose of this study was to examine the relative importance of leadership communication in predicting burnout and intention to stay among faculty and staff while controlling for other factors such as satisfaction with compensation and work-home flexibility. METHODS: This study involved a secondary analysis of data derived from an organizational engagement survey that included 2336 faculty members (75% response rate) and 17,664 staff members (72% response rate). RESULTS: Effective leadership communication was a stronger predictor of burnout and intent to stay than satisfaction with compensation and work-home flexibility. Feeling valued by the organization mediated the relationship between leadership communication and the outcome variables. CONCLUSIONS: Leadership communication provides a low-cost solution to burnout and staff shortages and is primarily effective because it conveys to both faculty and staff that they are valued by the organization.


Assuntos
Esgotamento Profissional , Recursos Humanos de Enfermagem Hospitalar , Humanos , Liderança , Satisfação no Emprego , Esgotamento Profissional/prevenção & controle , Intenção , Inquéritos e Questionários , Reorganização de Recursos Humanos , Comunicação , Atenção à Saúde
5.
BMC Public Health ; 24(1): 931, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561729

RESUMO

BACKGROUND: Rising housing prices are becoming a top public health priority and are an emerging concern for policy makers and community leaders. This report reviews and synthesizes evidence examining the association between changes in housing price and health outcomes. METHODS: We conducted a systematic literature review by searching the SCOPUS and PubMed databases for keywords related to housing price and health. Articles were screened by two reviewers for eligibility, which restricted inclusion to original research articles measuring changes in housing prices and health outcomes, published prior to June 31st, 2022. RESULTS: Among 23 eligible studies, we found that changes in housing prices were heterogeneously associated with physical and mental health outcomes, with multiple mechanisms contributing to both positive and negative health outcomes. Income-level and home-ownership status were identified as key moderators, with lower-income individuals and renters experience negative health consequences from rising housing prices. This may have resulted from increased stress and financial strain among these groups. Meanwhile, the economic benefits of rising housing prices were seen to support health for higher-income individuals and homeowners - potentially due to increased wealth or perception of wealth. CONCLUSIONS: Based on the associations identified in this review, it appears that potential gains to health associated with rising housing prices are inequitably distributed. Housing policies should consider the health inequities born by renters and low-income individuals. Further research should explore mechanisms and interventions to reduce uneven economic impacts on health.


Assuntos
Habitação , Humanos , Habitação/economia
6.
Mol Plant Pathol ; 25(4): e13458, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619888

RESUMO

Due to rapidly emerging resistance to single-site fungicides in fungal pathogens of plants, there is a burgeoning need for safe and multisite fungicides. Plant antifungal peptides with multisite modes of action (MoA) have potential as bioinspired fungicides. Medicago truncatula defensin MtDef4 was previously reported to exhibit potent antifungal activity against fungal pathogens. Its MoA involves plasma membrane disruption and binding to intracellular targets. However, specific biochemical processes inhibited by this defensin and causing cell death have not been determined. Here, we show that MtDef4 exhibited potent antifungal activity against Botrytis cinerea. It induced severe plasma membrane and organelle irregularities in the germlings of this pathogen. It bound to fungal ribosomes and inhibited protein translation in vitro. A MtDef4 variant lacking antifungal activity exhibited greatly reduced protein translation inhibitory activity. A cation-tolerant MtDef4 variant was generated that bound to ß-glucan of the fungal cell wall with higher affinity than MtDef4. It also conferred a greater reduction in the grey mould disease symptoms than MtDef4 when applied exogenously on Nicotiana benthamiana plants, tomato fruits and rose petals. Our findings revealed inhibition of protein synthesis as a likely target of MtDef4 and the potential of its cation-tolerant variant as a peptide-based fungicide.


Assuntos
Antifúngicos , Fungicidas Industriais , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Fungicidas Industriais/farmacologia , Plantas/metabolismo , Peptídeos , Defensinas/genética , Defensinas/farmacologia , Defensinas/metabolismo , Cátions , Doenças das Plantas/microbiologia , Botrytis/metabolismo
7.
Clin Chem ; 70(3): 538-550, 2024 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431278

RESUMO

BACKGROUND: The sensitivity of amyloid to pre-analytic factors complicates cerebrospinal fluid (CSF) diagnostics for Alzheimer disease. We report reliability and validity evidence for automated immunoassays from frozen and fresh CSF samples in an ongoing, single-site research program. METHODS: CSF samples were obtained from 2 Wisconsin cohorts (1256 measurements; 727 participants). Levels of amyloid beta 1-42 (Aß42), phosphorylated tau 181 (pTau181), and total tau (tTau) were obtained using an Elecsys cobas e 601 platform. Repeatability and fixed effects of storage tube type, extraction method, and freezing were assessed via mixed models. Concordance with amyloid positron emission tomography (PET) was investigated with 238 participants having a temporally proximal PET scan. RESULTS: Repeatability was high with intraclass correlation (ICC) ≥0.9, but tube type strongly affected measurements. Discriminative accuracy for PET amyloid positivity was strong across tube types (area under the curve [AUC]: Aß42, 0.87; pTau181Aß42 , 0.96), although optimal thresholds differed. CONCLUSIONS: Under real-world conditions, the Elecsys platform had high repeatability. However, strong effects of pre-analytic factors suggest caution in drawing longitudinal inferences.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Reprodutibilidade dos Testes , Proteínas tau/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons , Biomarcadores/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano
8.
Mol Cancer Ther ; 23(4): 454-463, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38205881

RESUMO

Proteolysis targeting chimeras (PROTAC) are an emerging precision medicine strategy, which targets key proteins for proteolytic degradation to ultimately induce cancer cell killing. These hetero-bifunctional molecules hijack the ubiquitin proteasome system to selectively add polyubiquitin chains onto a specific protein target to induce proteolytic degradation. Importantly, PROTACs have the capacity to target virtually any intracellular and transmembrane protein for degradation, including oncoproteins previously considered undruggable, which strategically positions PROTACs at the crossroads of multiple cancer research areas. In this review, we present normal functions of the ubiquitin regulation proteins and describe the application of PROTACs to improve the efficacy of current broad-spectrum therapeutics. We subsequently present the potential for PROTACs to exploit specific cancer vulnerabilities through synthetic genetic approaches, which may expedite the development, translation, and utility of novel synthetic genetic therapies in cancer. Finally, we describe the challenges associated with PROTACs and the ongoing efforts to overcome these issues to streamline clinical translation. Ultimately, these efforts may lead to their routine clinical use, which is expected to revolutionize cancer treatment strategies, delay familial cancer onset, and ultimately improve the lives and outcomes of those living with cancer.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Quimera de Direcionamento de Proteólise , Proteínas de Membrana , Neoplasias/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma , Proteólise , Ubiquitina , Ubiquitina-Proteína Ligases
9.
Cell Mol Gastroenterol Hepatol ; 17(4): 623-638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38163482

RESUMO

Hepatobiliary cancers (HBCs) include hepatocellular carcinoma, cholangiocarcinoma, and gallbladder carcinoma, which originate from the liver, bile ducts, and gallbladder, respectively. They are responsible for a substantial burden of cancer-related deaths worldwide. Despite knowledge of risk factors and advancements in therapeutics and surgical interventions, the prognosis for most patients with HBC remains bleak. There is evidence from familial aggregation and case-control studies to suggest a familial risk component in HBC susceptibility. Recent progress in genomics research has led to the identification of germline variants including single nucleotide polymorphisms (SNPs) and pathogenic or likely pathogenic (P/LP) variants in cancer-associated genes associated with HBC risk. These findings emerged from genome-wide association studies and next-generation sequencing techniques such as whole-exome sequencing. Patients with other cancer types, including breast, colon, ovarian, prostate, and pancreatic cancer, are recommended by guidelines to undergo germline genetic testing, but similar recommendations are lagging in HBC. This prompts the question of whether multi-gene panel testing should be integrated into clinical guidelines for HBC management. Here, we review the hereditary genetics of HBC, explore studies investigating SNPs and P/LP variants in HBC patients, discuss the clinical implications and potential for personalized treatments and impact on patient's family members, and conclude that additional studies are needed to examine how genetic testing can be applied clinically.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias Pancreáticas , Masculino , Humanos , Predisposição Genética para Doença , Testes Genéticos/métodos , Neoplasias Pancreáticas/genética , Células Germinativas
10.
Cancer Treat Res Commun ; 38: 100789, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38262125

RESUMO

BACKGROUND: Glioblastoma is the most common primary malignant and treatment-resistant human brain tumor. Rodent models have played an important role in understanding brain cancer biology and treatment. However, due to their small cranium and tumor volume mismatch, relative to human disease, they have been less useful for translational studies. Therefore, development of a consistent and simple large animal glioma xenograft model would have significant translational benefits. METHODS: Immunosuppression was induced in twelve standard Yucatan minipigs. 3 pigs received cyclosporine only, while 9 pigs received a combined regimen including cyclosporine (55 mg/kg q12 h), prednisone (25 mg, q24 h) and mycophenolate (500 mg q24 h). U87 cells (2 × 106) were stereotactically implanted into the left frontal cortex. The implanted brains were imaged by MRI for monitoring. In a separate study, tumors were grown in 5 additional pigs using the combined regimen, and pigs underwent tumor resection with intra-operative image updating to determine if the xenograft model could accurately capture the spatial tumor resection challenges seen in humans. RESULTS: Tumors were successfully implanted and grown in 11 pigs. One animal in cyclosporine only group failed to show clinical tumor growth. Clinical tumor growth, assessed by MRI, progressed slowly over the first 10 days, then rapidly over the next 10 days. The average tumor growth latency period was 20 days. Animals were monitored twice daily and detailed records were kept throughout the experimental period. Pigs were sacrificed humanely when the tumor reached 1 - 2 cm. Some pigs experienced decreased appetite and activity, however none required premature euthanasia. In the image updating study, all five pigs demonstrated brain shift after craniotomy, consistent with what is observed in humans. Intraoperative image updating was able to accurately capture and correct for this shift in all five pigs. CONCLUSION: This report demonstrates the development and use of a human intracranial glioma model in an immunosuppressed, but nongenetically modified pig. While the immunosuppression of the model may limit its utility in certain studies, the model does overcome several limitations of small animal or genetically modified models. For instance, we demonstrate use of this model for guiding surgical resection with intraoperative image-updating technologies. We further report use of a surrogate extracranial tumor that indicates growth of the intracranial tumor, allowing for relative growth assessment without radiological imaging.


Assuntos
Neoplasias Encefálicas , Ciclosporinas , Glioma , Humanos , Suínos , Animais , Xenoenxertos , Reprodutibilidade dos Testes , Porco Miniatura , Glioma/tratamento farmacológico , Glioma/cirurgia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Terapia de Imunossupressão , Modelos Animais de Doenças
12.
Rehabil Psychol ; 69(1): 70-73, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37917460

RESUMO

PURPOSE/OBJECTIVE: U.S. health organizations, including Division 22 of the American Psychological Association, the Society for Critical Care Medicine, and the American Thoracic Society advocate for psychological treatment that improves long-term outcomes in critical illness survivors. However, limited information exists with regard to psychology training opportunities in intensive care settings. We aim to identify and describe (a) existing psychology programs with training in intensive care settings and (b) barriers to finding these training opportunities. RESEARCH METHOD/DESIGN: Using aspects of the Arksey and O'Malley Framework and Preferred Reporting Items for Systematic Review and Meta-Analyses Extension for Scoping Reviews reporting checklist as guides, two independent reviewers searched the Association of Psychology Postdoctoral and Internship Centers (APPIC) Directory and Universal Psychology Postdoctoral Directory (UPPD) to identify programs with training experiences in intensive care settings. RESULTS: Searching the APPIC Directory did not reliably or accurately identify training opportunities in intensive care settings. Thus, only programs identified in the more reliable UPPD search were considered for inclusion. After duplicates were removed, searches using the UPPD yielded 31 programs for review. Of those, 22 programs met inclusion, offering heterogeneous training in intensive care settings. CONCLUSIONS/IMPLICATIONS: These results suggest few opportunities exist for psychology training in intensive care settings and available opportunities are difficult to identify using standard search methods. The identified challenges also emphasize the need for advanced search features for training opportunities within APPIC/UPPD and/or a list of programs offering these training opportunities. Our results highlight the importance of program descriptions that accurately and comprehensively reflect training opportunities-particularly relating to opportunities in intensive care settings. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Cuidados Críticos , Pós-Doutorado , Humanos , Estados Unidos
13.
Alzheimers Dement ; 20(2): 1050-1062, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37856321

RESUMO

INTRODUCTION: DNA microarray-based studies report differentially methylated positions (DMPs) in blood between late-onset dementia due to Alzheimer's disease (AD) and cognitively unimpaired individuals, but interrogate < 4% of the genome. METHODS: We used whole genome methylation sequencing (WGMS) to quantify DNA methylation levels at 25,409,826 CpG loci in 281 blood samples from 108 AD and 173 cognitively unimpaired individuals. RESULTS: WGMS identified 28,038 DMPs throughout the human methylome, including 2707 differentially methylated genes (e.g., SORCS3, GABA, and PICALM) encoding proteins in biological pathways relevant to AD such as synaptic membrane, cation channel complex, and glutamatergic synapse. One hundred seventy-three differentially methylated blood-specific enhancers interact with the promoters of 95 genes that are differentially expressed in blood from persons with and without AD. DISCUSSION: WGMS identifies differentially methylated CpGs in known and newly detected genes and enhancers in blood from persons with and without AD. HIGHLIGHTS: Whole genome DNA methylation levels were quantified in blood from persons with and without Alzheimer's disease (AD). Twenty-eight thousand thirty-eight differentially methylated positions (DMPs) were identified. Two thousand seven hundred seven genes comprise DMPs. Forty-eight of 75 independent genetic risk loci for AD have DMPs. One thousand five hundred sixty-eight blood-specific enhancers comprise DMPs, 173 of which interact with the promoters of 95 genes that are differentially expressed in blood from persons with and without AD.


Assuntos
Doença de Alzheimer , Metilação de DNA , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Epigênese Genética , Sequenciamento Completo do Genoma
14.
J Urol ; 211(3): 415-425, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38147400

RESUMO

PURPOSE: Less invasive decision support tools are desperately needed to identify occult high-risk disease in men with prostate cancer (PCa) on active surveillance (AS). For a variety of reasons, many men on AS with low- or intermediate-risk disease forgo the necessary repeat surveillance biopsies needed to identify potentially higher-risk PCa. Here, we describe the development of a blood-based immunocyte transcriptomic signature to identify men harboring occult aggressive PCa. We then validate it on a biopsy-positive population with the goal of identifying men who should not be on AS and confirm those men with indolent disease who can safely remain on AS. This model uses subtraction-normalized immunocyte transcriptomic profiles to risk-stratify men with PCa who could be candidates for AS. MATERIALS AND METHODS: Men were eligible for enrollment in the study if they were determined by their physician to have a risk profile that warranted prostate biopsy. Both training (n = 1017) and validation cohort (n = 1198) populations had blood samples drawn coincident to their prostate biopsy. Purified CD2+ and CD14+ immune cells were obtained from peripheral blood mononuclear cells, and RNA was extracted and sequenced. To avoid overfitting and unnecessary complexity, a regularized regression model was built on the training cohort to predict PCa aggressiveness based on the National Comprehensive Cancer Network PCa guidelines. This model was then validated on an independent cohort of biopsy-positive men only, using National Comprehensive Cancer Network unfavorable intermediate risk and worse as an aggressiveness outcome, identifying patients who were not appropriate for AS. RESULTS: The best final model for the AS setting was obtained by combining an immunocyte transcriptomic profile based on 2 cell types with PSA density and age, reaching an AUC of 0.73 (95% CI: 0.69-0.77). The model significantly outperforms (P < .001) PSA density as a biomarker, which has an AUC of 0.69 (95% CI: 0.65-0.73). This model yields an individualized patient risk score with 90% negative predictive value and 50% positive predictive value. CONCLUSIONS: While further validation in an intended-use cohort is needed, the immunocyte transcriptomic model offers a promising tool for risk stratification of individual patients who are being considered for AS.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Masculino , Humanos , Leucócitos Mononucleares/patologia , Conduta Expectante , Neoplasias da Próstata/patologia , Biópsia , Medição de Risco
15.
Methods Mol Biol ; 2725: 121-129, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37856021

RESUMO

Volume electron microscopy technologies such as serial block face scanning electron microscopy (SBF-SEM) allow the characterization of tissue organization and cellular content in three dimensions at nanoscale resolution. Here, we describe the procedure to process and image an air-liquid interface culture of human or mouse airway epithelial cells for visualization of the multiciliated epithelium by SBF-SEM in vertical or horizontal cross section.


Assuntos
Imageamento Tridimensional , Microscopia Eletrônica de Volume , Animais , Humanos , Camundongos , Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura , Epitélio , Células Epiteliais
17.
Gynecol Oncol ; 178: 80-88, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37820398

RESUMO

OBJECTIVE: Inhibition of the MAPK pathway by MEK inhibitors (MEKi) is currently a therapeutic standard in several cancer types, including ovarian low-grade serous carcinoma (LGSC). A common MAPK pathway alteration in tubo-ovarian high-grade serous carcinoma (HGSC) is the genomic inactivation of neurofibromin 1 (NF1). The primary objectives of our study were to survey the prevalence of NF1 inactivation in the principal ovarian carcinoma histotype as well as to evaluate its associations with clinico-pathological parameters and key biomarkers including BRCA1/2 status in HGSC. METHODS: A recently commercialized NF1 antibody (clone NFC) was orthogonally validated on an automated immunohistochemistry (IHC) platform and IHC was performed on tissue microarrays containing 2140 ovarian carcinoma cases. Expression was interpreted as loss/inactivated (complete or subclonal) versus normal/retained. RESULTS: Loss of NF1 expression was detected in 250/1429 (17.4%) HGSC including 11% with subclonal loss. Survival of NF1-inactivated HGSC patients was intermediate between favorable BRCA1/2 mutated HGSC and unfavorable CCNE1 high-level amplified HGSC. NF1 inactivation was mutually exclusive with CCNE1 high-level amplifications, co-occurred with RB1 loss and occurred at similar frequencies in BRCA1/2 mutated versus wild-type HGSC. NF1 loss was found in 21/286 (7.3%) endometrioid carcinomas with a favorable prognostic association (p = 0.048), and in 4/64 (5.9%) LGSC, mutually exclusive with other driver events. CONCLUSIONS: NF1 inactivation occurs in a significant subset of BRCA1/2 wild-type HGSC and a subset of LGSC. While the functional effects of NF1 inactivation need to be further characterized, this signifies a potential therapeutic opportunity to explore targeting NF1 inactivation in these tumors.


Assuntos
Carcinoma Endometrioide , Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Feminino , Humanos , Proteína BRCA1 , Neurofibromina 1/genética , Imuno-Histoquímica , Proteína BRCA2 , Neoplasias Ovarianas/patologia , Carcinoma Endometrioide/patologia , Cistadenocarcinoma Seroso/patologia , Carcinoma Epitelial do Ovário
18.
Materials (Basel) ; 16(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37687444

RESUMO

Peri-implantitis is a major cause of dental implant failure. This disease is an inflammation of the tissues surrounding the implant, and, while the cause is multi-factorial, bacteria is the main culprit in initiating an inflammatory reaction. Dental implants with silicon carbonitride (SiCN) coatings have several potential advantages over traditional titanium implants, but their antibacterial efficiency has not yet been evaluated. The purpose of this study was to determine the anti-bacterial potential of SiCN by modifying the surface of SiCN-coated implants to have a positive charge on the nitrogen atoms through the quaternization of the surface atoms. The changes in surface chemistry were confirmed using contact angle measurement and XPS analysis. The modified SiCN surfaces were inoculated with Streptococcus mutans (S. mutans) and compared with a silicon control. The cultured bacterial colonies for the experimental group were 80% less than the control silicon surface. Fluorescent microscopy with live bacteria staining demonstrated significantly reduced bacterial coverage after 3 and 7 days of incubation. Scanning electron microscopy (SEM) was used to visualize the coated surfaces after bacterial inoculation, and the mechanism for the antibacterial properties of the quaternized SiCN was confirmed by observing ruptured bacteria membrane along the surface.

19.
Microsc Microanal ; 29(Supplement_1): 1182, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37613220
20.
Materials (Basel) ; 16(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570022

RESUMO

The application of surface coatings is a popular technique to improve the performance of materials used for medical and dental implants. Ternary silicon carbon nitride (SiCN), obtained by introducing nitrogen into SiC, has attracted significant interest due to its potential advantages. This study investigated the properties of SiCN films deposited via PECVD for dental implant coatings. Chemical composition, optical, and tribological properties were analyzed by adjusting the gas flow rates of NH3, CH4, and SiH4. The results indicated that an increase in the NH3 flow rate led to higher deposition rates, scaling from 5.7 nm/min at an NH3 flow rate of 2 sccm to 7 nm/min at an NH3 flow rate of 8 sccm. Concurrently, the formation of N-Si bonds was observed. The films with a higher nitrogen content exhibited lower refractive indices, diminishing from 2.5 to 2.3 as the NH3 flow rate increased from 2 sccm to 8 sccm. The contact angle of SiCN films had minimal differences, while the corrosion rate was dependent on the pH of the environment. These findings contribute to a better understanding of the properties and potential applications of SiCN films for use in dental implants.

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