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1.
J Invest Dermatol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38583742

RESUMO

Peripheral blood transcriptomes from 383 newly-diagnosed melanoma patients were subjected to differential gene expression analysis. The hypotheses were that impaired systemic immunity is associated with poorer prognosis (thicker tumors and fewer tumor infiltrating lymphocytes (TILs)) and evidence of systemic inflammation (high-sensitivity C-reactive protein (hsCRP) and fibrinogen levels). Higher fibrinogen levels were associated with thicker primaries. In single gene analysis hsCRP levels were significantly associated with higher blood CD274 expression, (coding for PD-L1), but each was independently prognostic, with hsCRP associated with increased mortality, and higher CD274 protective, independent of age. Pathway analysis identified downregulation of immune cell signalling pathways in the blood of people with thicker tumors and notable upregulation of STAT1 in people with brisk TILs. Transcriptomic data provided evidence for increased NFB signalling with higher inflammatory markers but with reduction in expression of HLA class II molecules and higher CD274 suggesting that aberrant systemic inflammation is a significant mediator of reduced immune function in melanoma. In summary, transcriptomic data revealed evidence of reduced immune function in patients with thicker tumors and fewer TILs, at diagnosis. Inflammatory markers were associated with thicker primaries and independently with death from melanoma suggesting that systemic inflammation contributes to that reduced immune function.

2.
J Sex Med ; 21(4): 278-287, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38383071

RESUMO

BACKGROUND: Transformation of resident fibroblasts to profibrotic myofibroblasts in the tunica albuginea is a critical step in the pathophysiology of Peyronie's disease (PD). We have previously shown that myofibroblasts do not revert to the fibroblast phenotype and we suggested that there is a point of no return at 36 hours after induction of the transformation. However, the molecular mechanisms that drive this proposed irreversibility are not known. AIM: Identify molecular pathways that drive the irreversibility of myofibroblast transformation by analyzing the expression of the genes involved in the process in a temporal fashion. METHODS: Human primary fibroblasts obtained from tunica albuginea of patients with Peyronie's disease were transformed to myofibroblasts using transforming growth factor beta 1 (TGF-ß1). The mRNA of the cells was collected at 0, 24, 36, 48, and 72 hours after stimulation with TGF-ß1 and then analyzed using a Nanostring nCounter Fibrosis panel. The gene expression results were analyzed using Reactome pathway analysis database and ANNi, a deep learning-based inference algorithm based on a swarm approach. OUTCOMES: The study outcome was the time course of changes in gene expression during transformation of PD-derived fibroblasts to myofibroblasts. RESULTS: The temporal analysis of the gene expression revealed that the majority of the changes at the gene expression level happened within the first 24 hours and remained so throughout the 72-hour period. At 36 hours, significant changes were observed in genes involved in MAPK-Hedgehog signaling pathways. CLINICAL TRANSLATION: This study highlights the importance of early intervention in clinical management of PD and the future potential of new drugs targeting the point of no return. STRENGTHS AND LIMITATIONS: The use of human primary cells and confirmation of results with further RNA analysis are the strengths of this study. The study was limited to 760 genes rather than the whole transcriptome. CONCLUSION: This study is to our knowledge the first analysis of temporal gene expression associated with the regulation of the transformation of resident fibroblasts to profibrotic myofibroblasts in PD. Further research is warranted to investigate the role of the MAPK-Hedgehog signaling pathways in reversibility of PD.


Assuntos
Induração Peniana , Masculino , Humanos , Induração Peniana/genética , Miofibroblastos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Hedgehog/metabolismo , Pênis , Células Cultivadas , Fibroblastos/metabolismo
3.
J Adolesc Health ; 74(3): 441-448, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38069926

RESUMO

PURPOSE: Adolescent alcohol consumption is detrimental to multiple facets of health. However, there is a scarcity of data available on time trends in adolescents' alcohol consumption particularly from non-Western countries and low- and middle-income countries. Thus, we examined the temporal trend of alcohol use in a large representative sample of school-going adolescents aged 12-15 years from 22 countries in Africa, Asia, and the Americas. METHODS: Data from the Global School-based Student Health Survey were analyzed. Alcohol consumption referred to consuming alcohol on at least one day in the past 30 days. Crude linear trends of past 30-day alcohol consumption by country were assessed by linear regression models. RESULTS: Data on 135,426 adolescents aged 12-15 years were analyzed [mean (standard deviation) age 13.8 (1.0) years; 52.0% females]. The overall mean prevalence of past 30-day alcohol consumption was 14.1%. Of the 22 countries included in the study, increasing, decreasing, and stable trends were observed in 3, 8, and 11 countries, respectively. Specifically, significant increases were observed in Benin between 2009 (16.1%) and 2016 (38.6%), Myanmar between 2007 (0.9%) and 2016 (3.6%), and Vanuatu between 2011 (7.6%) and 2016 (12.2%). The most drastic decrease was observed in Samoa between 2011 (34.5%) and 2017 (9.8%), but the rate of decrease was modest in most countries. DISCUSSION: Among school-going adolescents, decreasing trends in alcohol consumption were more common than increasing trends, but the rate of decrease was limited in most countries, suggesting that more global action is required to curb adolescent alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas , Consumo de Álcool por Menores , Feminino , Humanos , Adolescente , Masculino , Prevalência , Consumo de Bebidas Alcoólicas/epidemiologia , África/epidemiologia , Ásia/epidemiologia
4.
J Affect Disord ; 346: 192-199, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37952907

RESUMO

BACKGROUND: Perceived loneliness in adolescence is associated with a plethora of adverse outcomes. However, data on its temporal trends are scarce. Therefore, we aimed to examine the temporal trend of perceived loneliness among school-going adolescents aged 12-15 years from 28 countries in Africa, Asia, and the Americas, where temporal trends of loneliness are largely unknown. METHODS: Cross-sectional data from the Global School-based Student Health Survey 2003-2017 were analyzed. Perceived loneliness referred to feeling lonely most of the time or always in the past 12 months. Crude linear trends of perceived loneliness by country were assessed by linear regression models. RESULTS: Data on 180,087 adolescents aged 12-15 years were analyzed [Mean (SD) age 13.7 (1.0) years; 51.4 % females]. The overall prevalence of perceived loneliness was 10.7 %. Among the 28 countries included in the study, significant increasing and decreasing trends were observed in six counties each, with stable trends found in 16 countries. The most drastic increase and decrease were observed in Egypt between 2006 (7.9 %) and 2011 (14.3 %), and in Samoa between 2011 (23.3 %) and 2017 (8.0 %), respectively. Stable trends with high prevalence across time were also common. CONCLUSION: Our data suggest that perceived loneliness among adolescents is a global phenomenon, which has seen little improvement if any in recent years. It would be prudent to implement nationwide policies to combat loneliness globally.


Assuntos
Solidão , Feminino , Humanos , Adolescente , Masculino , Estudos Transversais , Ásia , África/epidemiologia , Inquéritos e Questionários , Prevalência
5.
Inorg Chem ; 62(46): 18901-18914, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37939015

RESUMO

Octahedral ruthenium(II) complexes of a xanthene-di(N-heterocyclic carbene) ancillary ligand (XdC) have been prepared and structurally characterized. Examples catalyze the transfer hydrogenation of ketones {[Ru(CO)I2(C,O,C'-XdC)] (1) and [Ru(CO)(MeCN)2(C,O,C'-XdC)]2+ (22+)} and the selective electrochemical reduction of CO2 to CO {[Ru(N,N'-bpy)(CO)(C,O,C'-XdC)]2+ (32+) at 0.40 V overpotential in MeCN-H2O (1 M)}. The reaction of 1 with KBEt3H afforded isomers of [(C,C'-XdC)Ru(µ-H)(H)]2 dimers, which are stable to reductive elimination of the XdC ligand, thereby suggesting similar (XdC)Rh(coligand)(H)x species may be viable intermediates in catalyses. The electrochemical reduction of CO2 involves a double reduction of 32+ to 3••, which has been characterized by IR-SEC and DFT calculations. The DFT calculations suggest the Ru-Oxanth bond breaks in 3••, opening a metal site for CO2 binding with selectivity over protons enabled by the diffuse nature of the HOMO delocalized over the metal and the bipyridine and carbonyl coligands. The results point to the promise of metal complexes of flexible and hemilabile xanthene-(NHC)2 ancillary ligands in catalysis.

6.
Sci Rep ; 13(1): 21163, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036593

RESUMO

DARPP-32 is a key regulator of protein-phosphatase-1 (PP-1) and protein kinase A (PKA), with its function dependent upon its phosphorylation state. We previously identified DKK1 and GRB7 as genes with linked expression using Artificial Neural Network (ANN) analysis; here, we determine protein expression in a large cohort of early-stage breast cancer patients. Low levels of DARPP-32 Threonine-34 phosphorylation and DKK1 expression were significantly associated with poor patient prognosis, while low levels of GRB7 expression were linked to better survival outcomes. To gain insight into mechanisms underlying these associations, we analysed the transcriptome of T47D breast cancer cells following DARPP-32 knockdown. We identified 202 differentially expressed transcripts and observed that some overlapped with genes implicated in the ANN analysis, including PTK7, TRAF5, and KLK6, amongst others. Furthermore, we found that treatment of DARPP-32 knockdown cells with 17ß-estradiol or PKA inhibitor fragment (6-22) amide led to the differential expression of 193 and 181 transcripts respectively. These results underscore the importance of DARPP-32, a central molecular switch, and its downstream targets, DKK1 and GRB7 in breast cancer. The discovery of common genes identified by a combined patient/cell line transcriptomic approach provides insights into the molecular mechanisms underlying differential breast cancer prognosis and highlights potential targets for therapeutic intervention.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/metabolismo , Moléculas de Adesão Celular/metabolismo , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Fosforilação , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Transcriptoma
7.
Cells ; 12(20)2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37887327

RESUMO

Meningioma, a primary brain tumor, is commonly encountered and accounts for 39% of overall CNS tumors. Despite significant progress in clinical research, conventional surgical and clinical interventions remain the primary treatment options for meningioma. Several proteomics and transcriptomics studies have identified potential markers and altered biological pathways; however, comprehensive exploration and data integration can help to achieve an in-depth understanding of the altered pathobiology. This study applied integrated meta-analysis strategies to proteomic and transcriptomic datasets comprising 48 tissue samples, identifying around 1832 common genes/proteins to explore the underlying mechanism in high-grade meningioma tumorigenesis. The in silico pathway analysis indicated the roles of extracellular matrix organization (EMO) and integrin binding cascades in regulating the apoptosis, angiogenesis, and proliferation responsible for the pathobiology. Subsequently, the expression of pathway components was validated in an independent cohort of 32 fresh frozen tissue samples using multiple reaction monitoring (MRM), confirming their expression in high-grade meningioma. Furthermore, proteome-level changes in EMO and integrin cell surface interactions were investigated in a high-grade meningioma (IOMM-Lee) cell line by inhibiting integrin-linked kinase (ILK). Inhibition of ILK by administrating Cpd22 demonstrated an anti-proliferative effect, inducing apoptosis and downregulating proteins associated with proliferation and metastasis, which provides mechanistic insight into the disease pathophysiology.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/genética , Proteômica , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Neoplasias Meníngeas/genética , Proliferação de Células , Integrinas
8.
Psychiatry Res ; 328: 115485, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37729716

RESUMO

Food insecurity may be a risk factor for depression in adolescents. However, data on this topic from low- and middle-income countries (LMICs) are scarce, despite food insecurity being most common in LMICs. Therefore, we aimed to examine the association between food-insecurity and depressive symptoms among school-going adolescents from 22 LMICs. Cross-sectional data from the Global school-based Student Health Survey were analyzed. Self-report measures assessed past 12-month depressive symptoms and past 30-day food insecurity (hunger). Multivariable logistic regression and meta-analysis were conducted to assess associations. Data on 48,401 adolescents aged 12-15 years were analyzed [mean (SD) age 13.8 (0.9) years; 51.4 % females]. The prevalence of depressive symptoms was 29.3 %, and those of moderate and severe food insecurity were 45.0 and 6.3 %, respectively. After adjustment for potential confounders, compared to no food insecurity, the pooled OR (95 %CI) of moderate and severe food insecurity were 1.36 (1.30-1.42) and 1.81 (1.67-1.97), respectively. The level of between-country heterogeneity was low. Food insecurity was associated with significantly higher odds for depressive symptoms among adolescents in LMICs. Policies to address food insecurity may also help prevent depression in this population, pending future longitudinal research.


Assuntos
Depressão , Países em Desenvolvimento , Adolescente , Feminino , Humanos , Masculino , Estudos Transversais , Depressão/epidemiologia , Insegurança Alimentar , Abastecimento de Alimentos , Pobreza , Criança
9.
Clin Proteomics ; 20(1): 41, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37770851

RESUMO

BACKGROUND: Meningiomas are the most prevalent primary brain tumors. Due to their increasing burden on healthcare, meningiomas have become a pivot of translational research globally. Despite many studies in the field of discovery proteomics, the identification of grade-specific markers for meningioma is still a paradox and requires thorough investigation. The potential of the reported markers in different studies needs further verification in large and independent sample cohorts to identify the best set of markers with a better clinical perspective. METHODS: A total of 53 fresh frozen tumor tissue and 51 serum samples were acquired from meningioma patients respectively along with healthy controls, to validate the prospect of reported differentially expressed proteins and claimed markers of Meningioma mined from numerous manuscripts and knowledgebases. A small subset of Glioma/Glioblastoma samples were also included to investigate inter-tumor segregation. Furthermore, a simple Machine Learning (ML) based analysis was performed to evaluate the classification accuracy of the list of proteins. RESULTS: A list of 15 proteins from tissue and 12 proteins from serum were found to be the best segregator using a feature selection-based machine learning strategy with an accuracy of around 80% in predicting low grade (WHO grade I) and high grade (WHO grade II and WHO grade III) meningiomas. In addition, the discriminant analysis could also unveil the complexity of meningioma grading from a segregation pattern, which leads to the understanding of transition phases between the grades. CONCLUSIONS: The identified list of validated markers could play an instrumental role in the classification of meningioma as well as provide novel clinical perspectives in regard to prognosis and therapeutic targets.

10.
BMC Med ; 21(1): 154, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076885

RESUMO

BACKGROUND: Dysfunctional adipose tissue (AT) is known to contribute to the pathophysiology of metabolic disease, including type 2 diabetes mellitus (T2DM). This dysfunction may occur, in part, as a consequence of gut-derived endotoxaemia inducing changes in adipocyte mitochondrial function and reducing the proportion of BRITE (brown-in-white) adipocytes. Therefore, the present study investigated whether endotoxin (lipopolysaccharide; LPS) directly contributes to impaired human adipocyte mitochondrial function and browning in human adipocytes, and the relevant impact of obesity status pre and post bariatric surgery. METHODS: Human differentiated abdominal subcutaneous (AbdSc) adipocytes from participants with obesity and normal-weight participants were treated with endotoxin to assess in vitro changes in mitochondrial function and BRITE phenotype. Ex vivo human AbdSc AT from different groups of participants (normal-weight, obesity, pre- and 6 months post-bariatric surgery) were assessed for similar analyses including circulating endotoxin levels. RESULTS: Ex vivo AT analysis (lean & obese, weight loss post-bariatric surgery) identified that systemic endotoxin negatively correlated with BAT gene expression (p < 0.05). In vitro endotoxin treatment of AbdSc adipocytes (lean & obese) reduced mitochondrial dynamics (74.6% reduction; p < 0.0001), biogenesis (81.2% reduction; p < 0.0001) and the BRITE phenotype (93.8% reduction; p < 0.0001). Lean AbdSc adipocytes were more responsive to adrenergic signalling than obese AbdSc adipocytes; although endotoxin mitigated this response (92.6% reduction; p < 0.0001). CONCLUSIONS: Taken together, these data suggest that systemic gut-derived endotoxaemia contributes to both individual adipocyte dysfunction and reduced browning capacity of the adipocyte cell population, exacerbating metabolic consequences. As bariatric surgery reduces endotoxin levels and is associated with improving adipocyte functionality, this may provide further evidence regarding the metabolic benefits of such surgical interventions.


Assuntos
Diabetes Mellitus Tipo 2 , Endotoxemia , Humanos , Endotoxemia/metabolismo , Adipócitos/metabolismo , Obesidade/metabolismo , Lipopolissacarídeos , Endotoxinas/metabolismo
11.
Curr Top Med Chem ; 23(7): 551-578, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37073654

RESUMO

Malaria is one of the neglected infectious diseases, and drugs are the first line of action taken against the onset of malaria as therapeutics. The drugs can be of either natural or artificial origin. Drug development has multiple impediments grouped under three categories, a. drug discovery and screening, b. the drug's action on the host and the pathogen, and c. clinical trials. Drug development takes coon's age from discovery to the market after FDA approval. At the same time, targeted organisms develop drug resistance quicker than drug approval, raising the requirement for advancement in drug development. The approach to explore drug candidates using the classical methods from natural sources, computation-based docking, mathematical and machine learningbased high throughput in silico models or drug repurposing has been investigated and developed. Also, drug development with information about the interaction between Plasmodium species and its host, humans, may facilitate obtaining an efficient drug cohort for further drug discovery or repurposing expedition. However, drugs may have side effects on the host system. Hence, machine learning and systems-based approaches may provide a holistic view of genomic, proteomic, and transcriptomic data and their interaction with the selected drug candidates. This review comprehensively describes the drug discovery workflows using drug and target screening methodologies, followed by possible ways to check the binding affinity of the drug and targets using various docking software.


Assuntos
Malária , Proteômica , Humanos , Genômica , Biologia Computacional , Descoberta de Drogas , Malária/tratamento farmacológico , Reposicionamento de Medicamentos
12.
Breast Cancer Res Treat ; 197(2): 245-254, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36427119

RESUMO

PURPOSE: Ductal carcinoma in situ (DCIS) associated with invasive carcinoma ≤ 1 mm in size is defined as DCIS with microinvasion (DCIS/microinvasion) rather than as invasive breast carcinoma. The number of patients with microinvasion accounts for < 1% of all breast cancer in published studies. As the numbers are limited, the prognostic significance of DCIS/microinvasion has not been clearly elucidated. This meta-analysis aimed to investigate the survival differences between patients with DCIS/microinvasion and those with pure DCIS. METHODS: A meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was performed. We searched three electronic databases (MEDLINE, Cochrane Library, and EMBASE) and included observational studies published in English that contained survival details of patients with either DCIS or DCIS/microinvasion. RESULTS: This study identified 26 studies that described the clinicopathological characteristics of patients in both the DCIS and DCIS/microinvasion groups. Survival differences were evaluated in 10 of 26 studies. Disease-free survival and loco-regional recurrence-free survival were significantly shorter in patients with DCIS/microinvasion than in those with DCIS (Hazard ratio, 1.52; 95% confidence interval, 1.11-2.08; p = 0.01 and hazard ratio, 2.53; 95% confidence interval, 1.45-4.41; p = 0.001, respectively). Both overall survival and distant metastasis-free survival tended to be shorter in patients with DCIS/microinvasion than in patients with DCIS (Hazard ratio, 1.63; 95% CI, 0.63-4.23; p = 0.31 and hazard ratio, 1.85; 95% confidence interval, 0.74-4.66; p = 0.19, respectively) but the difference was not statistically significant. CONCLUSION: Our meta-analysis suggests that DCIS/microinvasion may display more aggressive biological and clinical behavior than pure DCIS, highlighting the potential need for closer follow-up and consideration of adjuvant treatment strategies in DCIS patients with microinvasive disease.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Humanos , Feminino , Carcinoma Intraductal não Infiltrante/patologia , Neoplasias da Mama/patologia , Prognóstico , Mama/patologia , Intervalo Livre de Doença , Carcinoma Ductal de Mama/patologia , Invasividade Neoplásica/patologia , Estudos Retrospectivos
13.
Front Immunol ; 14: 1308530, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38332914

RESUMO

Introduction: Early diagnosis of sepsis and discrimination from SIRS is crucial for clinicians to provide appropriate care, management and treatment to critically ill patients. We describe identification of mRNA biomarkers from peripheral blood leukocytes, able to identify severe, systemic inflammation (irrespective of origin) and differentiate Sepsis from SIRS, in adult patients within a multi-center clinical study. Methods: Participants were recruited in Intensive Care Units (ICUs) from multiple UK hospitals, including fifty-nine patients with abdominal sepsis, eighty-four patients with pulmonary sepsis, forty-two SIRS patients with Out-of-Hospital Cardiac Arrest (OOHCA), sampled at four time points, in addition to thirty healthy control donors. Multiple clinical parameters were measured, including SOFA score, with many differences observed between SIRS and sepsis groups. Differential gene expression analyses were performed using microarray hybridization and data analyzed using a combination of parametric and non-parametric statistical tools. Results: Nineteen high-performance, differentially expressed mRNA biomarkers were identified between control and combined SIRS/Sepsis groups (FC>20.0, p<0.05), termed 'indicators of inflammation' (I°I), including CD177, FAM20A and OLAH. Best-performing minimal signatures e.g. FAM20A/OLAH showed good accuracy for determination of severe, systemic inflammation (AUC>0.99). Twenty entities, termed 'SIRS or Sepsis' (S°S) biomarkers, were differentially expressed between sepsis and SIRS (FC>2·0, p-value<0.05). Discussion: The best performing signature for discriminating sepsis from SIRS was CMTM5/CETP/PLA2G7/MIA/MPP3 (AUC=0.9758). The I°I and S°S signatures performed variably in other independent gene expression datasets, this may be due to technical variation in the study/assay platform.


Assuntos
Sepse , Síndrome de Resposta Inflamatória Sistêmica , Adulto , Humanos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/genética , Sistemas Automatizados de Assistência Junto ao Leito , Sepse/diagnóstico , Sepse/genética , Biomarcadores , Inflamação/diagnóstico , Inflamação/genética , Expressão Gênica , RNA Mensageiro , Quimiocinas , Proteínas com Domínio MARVEL
14.
J Am Chem Soc ; 144(38): 17622-17629, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36121779

RESUMO

Here, we report the NMR spectroscopic analysis of the group 8 transition metal methane σ-complexes [η5-CpM(CO)2(CH4)][Al(OC(CF3)3)4] (M = Fe, Ru) at -90 °C in the weakly coordinating solvent 1,1,1,3,3,3-hexafluoropropane. The iron(II)-methane complex has a 1H resonance at δ -4.27, a 13C resonance at δ -53.0, and 1JC-H = 126 Hz for the bound methane fragment. The ruthenium(II)-methane complex has a 1H resonance at δ -2.10, a 13C resonance at δ -48.8, and a 1JC-H = 126 Hz for the bound methane fragment. DFT and ab initio calculations support these experimental observations and provide further detail on the structures of the [η5-CpM(CO)2(CH4)]+ (M = Fe, Ru) complexes of the Group 8 metals. Both the iron centered methane complex, [η5-CpFe(CO)2(CH4)][Al(OC(CF3)3)4], and the ruthenium centered methane complex, [η5-CpRu(CO)2(CH4)][Al(OC(CF3)3)4], are significantly less stable than the previously reported osmium-methane complex [η5-CpOs(CO)2(CH4)][Al(OC(CF3)3)4].

15.
Histopathology ; 81(6): 770-785, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36030496

RESUMO

BACKGROUND: Emerging evidence indicates that breast cancer (BC) patients whose tumours express HER2 protein without HER2 gene amplification (HER2-low), can benefit from antibody-drug conjugates (ADC). However, the current definition of HER2-low BC remains incomplete with low rates of concordance. This study aims to refine HER2-low definition with emphasis on distinguishing HER2 score 0 from score 1+ to identify patients who are eligible for ADC. METHODS: A BC cohort (n = 363) with HER2 IHC scores 0, 1+ and 2+ (without HER2 gene amplification) and available HER2 mRNA was included. HER2 staining intensity, pattern and subcellular localisation were reassessed. Artificial neural network analysis was applied to cluster the cohort and to distinguish HER2 score 0 from 1+. Reproducibility and reliability of the refined criteria were tested. RESULTS: HER2 IHC score 1+ was refined as membranous staining in invasive cells as either: (1) faint intensity in ≥ 20% of cells regardless the circumferential completeness, (2) weak complete staining in ≤ 10%, (3) weak incomplete staining in > 10% and (4) moderate incomplete staining in ≤ 10%. Based on this, 63% of the HER2-negative cases were reclassified as positive (HER2-low). The refined score showed perfect observer agreement compared to the moderate agreement in the original clinical scores. Similar results were generated when the refined score was applied on the independent BC cohorts. A proposal to refine the definition of other HER2 classes is presented. CONCLUSION: This study refined the definition of HER2-low BC based on correlation with HER2 mRNA and distinguished between HER2 IHC score 1+ and score 0 tumours.


Assuntos
Neoplasias da Mama , Imunoconjugados , Humanos , Feminino , Receptor ErbB-2/análise , Neoplasias da Mama/patologia , Imuno-Histoquímica , Reprodutibilidade dos Testes , Hibridização in Situ Fluorescente , RNA Mensageiro
16.
Nutrients ; 14(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35631192

RESUMO

Weight Loss Surgery (WLS), including sleeve-gastrectomy (SG), results in significant weight loss and improved metabolic health in severe obesity (BMI ≥ 35 kg/m2). Previous studies suggest post-operative health benefits are impacted by nutrient deficiencies, such as Vitamin D (25(OH)D) deficiency, while it is currently unknown whether nutrient levels may actually predict post-surgery outcomes. As such, this study investigated whether 25(OH)D levels could predict metabolic improvements in patients who underwent SG. Patients with severe obesity (n = 309; 75% female) undergoing SG participated in this ethics-approved, non-randomized retrospective cohort study. Anthropometry, clinical data, 25(OH)D levels and serum markers were collected at baseline, 6-, 12- and 18-months post-surgery. SG surgery resulted in significant improvements in metabolic health at 6- and 12-months post-surgery compared with baseline, as expected. Patients with higher baseline 25(OH)D had significantly lower HbA1c levels post-surgery (p < 0.01) and better post-surgical T2DM outcomes, including reduced weight regain (p < 0.05). Further analysis revealed that baseline 25(OH)D could predict HbA1c levels, weight regain and T2DM remission one-year post-surgery, accounting for 7.5% of HbA1c divergence (p < 0.01). These data highlight that higher circulating 25(OH)D levels are associated with significant metabolic health improvements post-surgery, notably, that such baseline levels are able to predict those who attain T2DM remission. This highlights the importance of 25(OH)D as a predictive biomarker of post-surgery benefits.


Assuntos
Diabetes Mellitus Tipo 2 , Derivação Gástrica , Obesidade Mórbida , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia , Feminino , Gastrectomia/métodos , Derivação Gástrica/métodos , Hemoglobinas Glicadas/análise , Humanos , Masculino , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Vitamina D , Vitaminas , Aumento de Peso
17.
Nat Chem ; 14(7): 801-804, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35469008

RESUMO

The σ-alkane complexes of transition metals, which contain an essentially intact alkane molecule weakly bound to the metal, have been well established as crucial intermediates in the activation of the strong C-H σ-bonds found in alkanes. Methane, the simplest alkane, binds even more weakly than larger alkanes. Here we report an example of a long-lived methane complex formed by directly binding methane as an incoming ligand to a reactive organometallic complex. Photo-ejection of carbon monoxide from a cationic osmium-carbonyl complex dissolved in an inert hydrofluorocarbon solvent saturated with methane at -90 °C affords an osmium(II) complex, [η5-CpOs(CO)2(CH4)]+, containing methane bound to the metal centre. Nuclear magnetic resonance (NMR) spectroscopy confirms the identity of the σ-methane complex and shows that the four protons of the metal-bound methane are in rapid exchange with each other. The methane ligand has a characteristically shielded 1H NMR resonance (δ -2.16), and the highly shielded carbon resonance (δ -56.3) shows coupling to the four attached protons (1JC-H = 127 Hz). The methane complex has an effective half-life of about 13 hours at -90 °C.


Assuntos
Metano , Prótons , Alcanos , Ligantes , Metais , Metano/química , Osmio
18.
Am J Cancer Res ; 12(2): 469-489, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35261781

RESUMO

Lymphovascular invasion (LVI) is a key step in breast cancer (BC) metastasis. Targeting the molecular drivers of LVI can improve BC patients' management. However, the underlying molecular mechanisms of LVI are complex and interconnected with various carcinogenesis pathways. This study aimed to identify the key regulatory gene associated with LVI and to investigate its mechanisms of action and prognostic significance. Artificial neural network (ANN) was applied to two large transcriptomic datasets of BC with well-characterised LVI status. Cyclin B2 (CCNB2) was identified in the top genes associated with LVI positivity. In vitro functional assays were carried out to assess the role of CCNB2 in tumour cell behaviour and their interactions with endothelial cells using a panel of BC cell lines. Large annotated BC cohorts were used to assess the clinical and prognostic role of CCNB2 at the transcriptomic and protein levels. Knockdown (KD) of CCNB2 mRNA reduced BC cell migration, inhibited proliferation, blocked the G2/M transition during the cell cycle and increased the number of apoptotic cells. Importantly, KD of CCNB2 reduced BC cell lines adherence and transmigration across endothelial cell lines. High CCNB2 protein expression was independently associated with LVI positivity in addition to other features of aggressive behaviour, including larger tumour size, higher histological grade, hormonal receptor-negativity, and HER2-positivity, and with shorter survival. We conclude that CCNB2 plays a crucial role in LVI development in BC, implying that CCNB2 could confer a promising therapeutic target to inhibit LVI and reduce metastatic events.

19.
ACS Biomater Sci Eng ; 8(2): 765-776, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35084839

RESUMO

Relative to two-dimensional (2D) culture, three-dimensional (3D) culture of primary neurons has yielded increasingly physiological responses from cells. Electrospun nanofiber scaffolds are frequently used as a 3D biomaterial support for primary neurons in neural tissue engineering, while hydrophobic surfaces typically induce aggregation of cells. Poly-l-lactic acid (PLLA) was electrospun as aligned PLLA nanofiber scaffolds to generate a structure with both qualities. Primary cortical neurons from E18 Sprague-Dawley rats cultured on aligned PLLA nanofibers generated 3D clusters of cells that extended highly aligned, fasciculated neurite bundles within 10 days. These clusters were viable for 28 days and responsive to AMPA and GABA. Relative to the 2D culture, the 3D cultures exhibited a more developed profile; mass spectrometry demonstrated an upregulation of proteins involved in cortical lamination, polarization, and axon fasciculation and a downregulation of immature neuronal markers. The use of artificial neural network inference suggests that the increased formation of synapses may drive the increase in development that is observed for the 3D cell clusters. This research suggests that aligned PLLA nanofibers may be highly useful for generating advanced 3D cell cultures for high-throughput systems.


Assuntos
Nanofibras , Animais , Nanofibras/química , Neurônios , Poliésteres , Ratos , Ratos Sprague-Dawley , Alicerces Teciduais/química
20.
J Clin Pathol ; 75(4): 263-269, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33766957

RESUMO

AIMS: The mechanisms that drive breast cancer (BC) progression and poor outcome are not fully understood. The human heat shock protein 90 alpha family class A member 1 (HSP90α) encoded by the HSP90ΑA1 gene has a vital role in cellular responses to stress and is implicated in the development and progression of many cancers. The current study aims to explore the clinical and prognostic importance of HSP90α in BC. METHODS: The Molecular Taxonomy of Breast Cancer International Consortium (n=1980); The Cancer Genome Atlas (n=1097) and the Breast Cancer Gene-Expression Miner (Bc-GenExMiner) BC datasets (n=5056) were used to evaluate HSP90ΑA1 mRNA expression. HSP90α protein expression was further assessed using immunohistochemistry in a large (n=911) well-characterised BC series. The association between mRNA and protein expressions with other clinicopathological parameters and outcome was analysed. RESULTS: High expression of HSP90ΑA1 both at the mRNA and protein levels was significantly associated with characteristics of BC poor prognosis, including high grade, lymphovascular invasion, poor Nottingham Prognostic Index and positive expression of p53 and PIK3CA. Outcome analysis revealed that high HSP90α protein expression is an independent predictor of shorter BC-specific survival. CONCLUSION: HSP90α can be used as a potential prognostic marker in BC. Further mechanistic studies are warranted to determine the underlying molecular mechanisms mediated by HSP90α in BC.


Assuntos
Neoplasias da Mama , Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Feminino , Proteínas de Choque Térmico , Humanos , Invasividade Neoplásica/patologia , Prognóstico
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