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1.
Cell ; 186(1): 98-111.e21, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36608662

RESUMO

In eukaryotes, DNA replication initiation requires assembly and activation of the minichromosome maintenance (MCM) 2-7 double hexamer (DH) to melt origin DNA strands. However, the mechanism for this initial melting is unknown. Here, we report a 2.59-Å cryo-electron microscopy structure of the human MCM-DH (hMCM-DH), also known as the pre-replication complex. In this structure, the hMCM-DH with a constricted central channel untwists and stretches the DNA strands such that almost a half turn of the bound duplex DNA is distorted with 1 base pair completely separated, generating an initial open structure (IOS) at the hexamer junction. Disturbing the IOS inhibits DH formation and replication initiation. Mapping of hMCM-DH footprints indicates that IOSs are distributed across the genome in large clusters aligning well with initiation zones designed for stochastic origin firing. This work unravels an intrinsic mechanism that couples DH formation with initial DNA melting to license replication initiation in human cells.


Assuntos
Replicação do DNA , Humanos , Proteínas de Ciclo Celular/metabolismo , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/metabolismo , Proteínas de Manutenção de Minicromossomo/metabolismo , Origem de Replicação
2.
Immunity ; 52(3): 499-512.e5, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32187518

RESUMO

Interleukin-17A (IL-17A), IL-17F, and IL-17A/F heterodimers are key cytokines of the innate and adaptive immune response. Dysregulation of the IL-17 pathway contributes to immune pathology, and it is therefore important to elucidate the molecular mechanisms that govern IL-17 recognition and signaling. The receptor IL-17RC is thought to act in concert with IL-17RA to transduce IL-17A-, IL-17F-, and IL-17A/F-mediated signals. We report the crystal structure of the extracellular domain of human IL-17RC in complex with IL-17F. In contrast to the expected model, we found that IL-17RC formed a symmetrical 2:1 complex with IL-17F, thus competing with IL-17RA for cytokine binding. Using biophysical techniques, we showed that IL-17A and IL-17A/F also form 2:1 complexes with IL-17RC, suggesting the possibility of IL-17RA-independent IL-17 signaling pathways. The crystal structure of the IL-17RC:IL-17F complex provides a structural basis for IL-17F signaling through IL-17RC, with potential therapeutic applications for respiratory allergy and inflammatory bowel diseases.


Assuntos
Interleucina-17/imunologia , Multimerização Proteica/imunologia , Receptores de Interleucina-17/imunologia , Transdução de Sinais/imunologia , Ligação Competitiva , Cristalografia por Raios X , Células HEK293 , Humanos , Interleucina-17/química , Interleucina-17/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Receptores de Interleucina-17/química , Receptores de Interleucina-17/metabolismo
3.
J Virol ; 98(2): e0188523, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38197632

RESUMO

Adenoviruses are a group of double-stranded DNA viruses that can mainly cause respiratory, gastrointestinal, and eye infections in humans. In addition, adenoviruses are employed as vector vaccines for combatting viral infections, including SARS-CoV-2, and serve as excellent gene therapy vectors. These viruses have the ability to modulate the host cell machinery to their advantage and trigger significant restructuring of the nuclei of infected cells through the activity of viral proteins. One of those, the adenovirus DNA-binding protein (DBP), is a multifunctional non-structural protein that is integral to the reorganization processes. DBP is encoded in the E2A transcriptional unit and is highly abundant in infected cells. Its activity is unequivocally linked to the formation, structure, and integrity of virus-induced replication compartments, molecular hubs for the regulation of viral processes, and control of the infected cell. DBP also plays key roles in viral DNA replication, transcription, viral gene expression, and even host range specificity. Notably, post-translational modifications of DBP, such as SUMOylation and extensive phosphorylation, regulate its biological functions. DBP was first investigated in the 1970s, pioneering research on viral DNA-binding proteins. In this literature review, we provide an overview of DBP and specifically summarize key findings related to its complex structure, diverse functions, and significant role in the context of viral replication. Finally, we address novel insights and perspectives for future research.


Assuntos
Adenoviridae , Replicação do DNA , Proteínas de Ligação a DNA , Proteínas Virais , Humanos , Adenoviridae/fisiologia , Adenovírus Humanos/fisiologia , DNA Viral/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral
4.
Mol Cell ; 67(2): 168-179, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28732205

RESUMO

A family of six homologous subunits, Mcm2, -3, -4, -5, -6, and -7, each with its own unique features, forms the catalytic core of the eukaryotic replicative helicase. The necessity of six similar but non-identical subunits has been a mystery since its initial discovery. Recent cryo-EM structures of the Mcm2-7 (MCM) double hexamer, its precursors, and the origin recognition complex (ORC)-Cdc6-Cdt1-Mcm2-7 (OCCM) intermediate showed that each of these subunits plays a distinct role in orchestrating the assembly of the pre-replication complex (pre-RC) by ORC-Cdc6 and Cdt1.


Assuntos
Replicação do DNA , Proteínas de Manutenção de Minicromossomo/metabolismo , Complexo de Reconhecimento de Origem/metabolismo , Animais , Domínio Catalítico , Proteínas de Ciclo Celular/metabolismo , Humanos , Proteínas de Manutenção de Minicromossomo/química , Proteínas de Manutenção de Minicromossomo/ultraestrutura , Modelos Moleculares , Complexos Multiproteicos , Proteínas Nucleares/metabolismo , Conformação de Ácido Nucleico , Complexo de Reconhecimento de Origem/química , Complexo de Reconhecimento de Origem/ultraestrutura , Ligação Proteica , Subunidades Proteicas , Relação Estrutura-Atividade
5.
Biochem J ; 481(13): 823-838, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38780411

RESUMO

The reaction centre-light harvesting 1 (RC-LH1) core complex is indispensable for anoxygenic photosynthesis. In the purple bacterium Rhodobacter (Rba.) sphaeroides RC-LH1 is produced both as a monomer, in which 14 LH1 subunits form a C-shaped antenna around 1 RC, and as a dimer, where 28 LH1 subunits form an S-shaped antenna surrounding 2 RCs. Alongside the five RC and LH1 subunits, an additional polypeptide known as PufX provides an interface for dimerisation and also prevents LH1 ring closure, introducing a channel for quinone exchange that is essential for photoheterotrophic growth. Structures of Rba. sphaeroides RC-LH1 complexes revealed several new components; protein-Y, which helps to form the quinone channel; protein-Z, of unknown function and seemingly unique to dimers; and a tightly bound sulfoquinovosyl diacylglycerol (SQDG) lipid that interacts with two PufX arginine residues. This lipid lies at the dimer interface alongside weak density for a second molecule, previously proposed to be an ornithine lipid. In this work we have generated strains of Rba. sphaeroides lacking protein-Y, protein-Z, SQDG or ornithine lipids to assess the roles of these previously unknown components in the assembly and activity of RC-LH1. We show that whilst the removal of either protein-Y, protein-Z or ornithine lipids has only subtle effects, SQDG is essential for the formation of RC-LH1 dimers but its absence has no functional effect on the monomeric complex.


Assuntos
Proteínas de Bactérias , Complexos de Proteínas Captadores de Luz , Multimerização Proteica , Rhodobacter sphaeroides , Rhodobacter sphaeroides/metabolismo , Rhodobacter sphaeroides/genética , Complexos de Proteínas Captadores de Luz/metabolismo , Complexos de Proteínas Captadores de Luz/química , Complexos de Proteínas Captadores de Luz/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Glicolipídeos/metabolismo , Glicolipídeos/química , Modelos Moleculares , Cristalografia por Raios X
6.
Genes Dev ; 31(11): 1073-1088, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28717046

RESUMO

DNA replication results in the doubling of the genome prior to cell division. This process requires the assembly of 50 or more protein factors into a replication fork. Here, we review recent structural and biochemical insights that start to explain how specific proteins recognize DNA replication origins, load the replicative helicase on DNA, unwind DNA, synthesize new DNA strands, and reassemble chromatin. We focus on the minichromosome maintenance (MCM2-7) proteins, which form the core of the eukaryotic replication fork, as this complex undergoes major structural rearrangements in order to engage with DNA, regulate its DNA-unwinding activity, and maintain genome stability.


Assuntos
Replicação do DNA/fisiologia , Animais , Cromatina/metabolismo , DNA Helicases/metabolismo , Replicação do DNA/genética , Evolução Molecular , Instabilidade Genômica/genética , Humanos , Proteínas de Manutenção de Minicromossomo/genética , Proteínas de Manutenção de Minicromossomo/metabolismo , Origem de Replicação/fisiologia
7.
J Infect Dis ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39328079

RESUMO

Multisystem Inflammatory Syndrome in Children (MIS-C) is a rare, potentially fatal complication of SARS-CoV-2 infection. Genetic defects in inflammation-related pathways have been linked to MIS-C, but additional research is needed, especially in diverse ethnic groups. The present study aimed to identify genetic variants underlying MIS-C in Brazilian patients. Whole-exome sequencing was performed, focusing on genes involved in the host immune response to SARS-CoV-2. Functional assays assessed the impact of selected variants on NF-κB signaling. Nine rare, potentially deleterious variants were found in eight of 21 patients, located in IL17RC, IFNA10, or NLRP12 genes. Unlike the wild-type NLRP12 protein, which inhibits NF-κB activation in HEK 293T cells, the mutant NLRP12 proteins have significantly reduced inhibitory properties. In conclusion, our results indicate that rare autosomal variants in immune-related genes may underlie MIS-C, highlighting the potential role of NLRP12 in its predisposition. These findings provide new insights for the appropriate management of MIS-C.

8.
Plant Cell Physiol ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39030709

RESUMO

Anoxygenic photosynthesis is diversified into two classes: chlorophototrophy based on a bacterial type-I or type-II reaction center (RC). Whereas the type-I RC contains both bacteriochlorophyll and chlorophyll, type-II RC-based phototrophy relies only on bacteriochlorophyll. However, type-II phototrophic bacteria theoretically have the potential to produce chlorophyll a by the addition of an enzyme, chlorophyll synthase, because the direct precursor for the enzyme, chlorophyllide a, is produced as an intermediate of BChl a biosynthesis. In this study, we attempted to modify the type-II proteobacterial phototroph Rhodovulum sulfidophilum to produce chlorophyll a by introducing chlorophyll synthase, which catalyzes the esterification of a diterpenoid group to chlorophyllide a thereby producing chlorophyll a. However, the resulting strain did not accumulate chlorophyll a, perhaps due to absence of endogenous chlorophyll a-binding proteins. We further heterologously incorporated genes encoding the type-I RC complex to provide a target for chlorophyll a. Heterologous expression of type-I RC subunits, chlorophyll synthase, and galactolipid synthase successfully afforded detectable accumulation of chlorophyll a in Rdv. sulfidophilum. This suggests that the type-I RC can work to accumulate chlorophyll a and that galactolipids are likely necessary for the type-I RC assembly. The evolutionary acquisition of type-I RCs could be related to prior or concomitant acquisition of galactolipids and chlorophylls.

9.
Arch Microbiol ; 206(4): 181, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502253

RESUMO

The α-L-arabinofuranosidase enzyme plays a crucial role in the degradation of ginsenosides. In this study, we successfully cloned and expressed a novel α-L-arabinofuranosidase bsafs gene (1503 bp, 501 amino acids, 55 kDa, and pI = 5.4) belonging to glycosyl hydrolase (GH) family 51 from Bacillus subtilis genome in Escherichia coli BL21 cells. The recombinant protein Bsafs was purified using Ni2+ sepharose fastflow affinity chromatography and exhibited a specific activity of 2.91 U/mg. Bsafs effectively hydrolyzed the α-L-arabinofuranoside at C20 site of ginsenoside Rc to produce Rd as the product. The Km values for hydrolysis of pNP-α-L-arabinofuranoside (pNPαAraf) and ginsenoside Rc were determined as 0.74 and 4.59 mmol/L, respectively; while the Vmax values for these substrates were found to be 24 and 164 µmol/min/mg, respectively; furthermore, the Kcat values for these enzymes were calculated as 22.3 and 1.58 S-1 correspondingly.


Assuntos
Ginsenosídeos , Ginsenosídeos/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Clonagem Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Glicosídeo Hidrolases/metabolismo , Especificidade por Substrato
10.
Protein Expr Purif ; 217: 106432, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38232795

RESUMO

Natural ginsenoside needs to be converted into rare ginsenoside before it can be readily absorbed into the bloodstream for action. In this study, an α-l-arabinofuranosidase (α-l-AFase) gene Bsafs2 was cloned from Bacillus subtilis (B. subtilis). Bsafs2 was ligated to the expression vector pET28a(+), and the expression vector was constructed and transformed into Escherichia coli (E. coli) BL21 heterologous recombinant expression to obtain α-l-AFase. α-l-AFase can hydrolyze at the C20 site of Ginsenoside Rc to obtain rare ginsenoside Rd. Studies on the enzymatic property showed that α-l-AFase had good tolerance to ethanol, glucose, and l-arabinose. The optimum temperature of α-l-AFase was 40 °C and pH = 5.5. Kinetic parameters Km of α-l-AFase for pNPαAraf and Ginsenoside Rc were 1.93 and 8.9 mmol/L, the Vmax were 26 and 154 µmol/min/mg, the Kcat were 24.14 and 1.48 S-1, respectively. This study provides the enzyme source for the biotransformation of Ginsenoside Rc.


Assuntos
Ginsenosídeos , Ginsenosídeos/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Clonagem Molecular , Proteínas Recombinantes/química , Escherichia coli/metabolismo , Glicosídeo Hidrolases/química
11.
Pharmacol Res ; 204: 107203, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719196

RESUMO

Recent research has demonstrated the immunomodulatory potential of Panax notoginseng in the treatment of chronic inflammatory diseases and cerebral hemorrhage, suggesting its significance in clinical practice. Nevertheless, the complex immune activity of various components has hindered a comprehensive understanding of the immune-regulating properties of Panax notoginseng, impeding its broader utilization. This review evaluates the effect of Panax notoginseng to various types of white blood cells, elucidates the underlying mechanisms, and compares the immunomodulatory effects of different Panax notoginseng active fractions, aiming to provide the theory basis for future immunomodulatory investigation.


Assuntos
Panax notoginseng , Panax notoginseng/química , Humanos , Animais , Sistema Imunitário/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia
12.
Inflamm Res ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164592

RESUMO

OBJECTIVE: Porphyromonas gingivalis (P. gingivalis), one of the major periodontopathogens, is associated with the progression and exacerbation of atherosclerosis. In this study, we aimed to investigate whether the gastrin-releasing peptide receptor antagonist, RC-3095, could attenuate P. gingivalis LPS-induced inflammatory responses in endothelial cells and macrophages, as well as atherosclerosis in an ApoE-/- mouse model treated with P. gingivalis LPS. METHODS: The effect of RC-3095 on P. gingivalis LPS-induced endothelial inflammation was examined using HUVECs and rat aortic endothelium. THP-1 cells were polarized into M1 macrophages by exposure to P. gingivalis LPS, with or without RC-3095. The effect of RC-3095 on atherosclerosis progression was assessed in high-fat-fed male ApoE-/- mice through injections of P. gingivalis LPS, RC-3095, or a combination of both. RESULTS: RC-3095 significantly reduced P. gingivalis LPS-induced leukocyte adhesion to endothelial cells and aortic endothelium by suppressing NF-κB-dependent expressions of ICAM-1 and VCAM-1. In addition, RC-3095 inhibited the P. gingivalis LPS-induced polarization of M1 macrophages by blocking the MAPK and NF-κB signaling pathways. Moreover, RC-3095 decreased the area of atherosclerotic lesions in ApoE-/- mice, which was accelerated by P. gingivalis LPS injection, and lowered the expressions of ICAM-1 and VCAM-1 in the aortic tissue of mice with atherosclerosis. CONCLUSIONS: RC-3095 can alleviate P. gingivalis LPS-induced endothelial inflammation, macrophage polarization, and atherosclerosis progression, suggesting its potential as a therapeutic approach for periodontal pathogen-associated atherosclerosis.

13.
Int J Geriatr Psychiatry ; 39(1): e6056, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38229210

RESUMO

OBJECTIVES: We have previously demonstrated difficulties in written production in dementia with Lewy bodies (DLB) patients. We now aim to determine the neural correlates of writing production in DLB, combining clinical data and structural MRI measures. METHOD: Sixteen prodromal to mild DLB patients were selected to participate in the study. The GREMOTS test was used to assess writing production. Using three-dimensional T1 brain MRI images, correlations between the GREMOTS test and grey matter (GM) volume were performed using voxel-based morphometry (VBM; SPM12, XjView and Matlab R2021b softwares). RESULTS: VBM analysis (p < 0.001, uncorrected) revealed a positive and significant correlation between both left anterior insula and left supramarginal gyrus GM volumes and DLB patients' ability to write logatoms using the phonological route. The handwriting deficit was negatively and significantly correlated to the supplementary motor area. The parkinsonism-like characteristics of agraphia were negatively and significantly correlated with both right anterior and right posterior cerebellum GM volumes. Our study also revealed a negative and significant correlation between grammatical spelling impairments and an area of the orbitofrontal gyrus, and a negative and significant correlation between supramarginal gyrus and general slowness in dictation tasks. CONCLUSION: Writing disorders in early DLB patients appears to be GM decreases in several brain regions, such as the left anterior insula, the left supramaginal gyrus, as well as two areas of the right cerebellum.


Assuntos
Demência , Doença por Corpos de Lewy , Humanos , Doença por Corpos de Lewy/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética , Redação
14.
Cell Mol Biol Lett ; 29(1): 50, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594618

RESUMO

BACKGROUND: Melanoma is the most lethal skin cancer characterized by its high metastatic potential. In the past decade, targeted and immunotherapy have brought revolutionary survival benefits to patients with advanced and metastatic melanoma, but these treatment responses are also heterogeneous and/or do not achieve durable responses. Therefore, novel therapeutic strategies for improving outcomes remain an unmet clinical need. The aim of this study was to evaluate the therapeutic potential and underlying molecular mechanisms of RC48, a novel HER2-target antibody drug conjugate, either alone or in combination with dabrafenib, a V600-mutant BRAF inhibitor, for the treatment of advanced BRAF-mutant cutaneous melanoma. METHODS: We evaluated the therapeutic efficacy of RC48, alone or in combination with dabrafenib, in BRAF-mutant cutaneous melanoma cell lines and cell-derived xenograft (CDX) models. We also conducted signaling pathways analysis and global mRNA sequencing to explore mechanisms underlying the synergistic effect of the combination therapy. RESULTS: Our results revealed the expression of membrane-localized HER2 in melanoma cells. RC48 effectively targeted and inhibited the growth of HER2-positive human melanoma cell lines and corresponding CDX models. When used RC48 and dabrafenib synergically induced tumor regression together in human BRAF-mutant melanoma cell lines and CDX models. Mechanically, our results demonstrated that the combination therapy induced apoptosis and cell cycle arrest while suppressing cell motility in vitro. Furthermore, global RNA sequencing analysis demonstrated that the combination treatment led to the downregulation of several key signaling pathways, including the PI3K-AKT pathway, MAPK pathway, AMPK pathway, and FOXO pathway. CONCLUSION: These findings establish a preclinical foundation for the combined use of an anti-HER2 drug conjugate and a BRAF inhibitor in the treatment of BRAF-mutant cutaneous melanoma.


Assuntos
Antineoplásicos , Imidazóis , Imunoconjugados , Melanoma , Oximas , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Neoplasias Cutâneas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Fosfatidilinositol 3-Quinases , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Imunoconjugados/genética , Imunoconjugados/uso terapêutico , Mutação
15.
Lipids Health Dis ; 23(1): 294, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267042

RESUMO

BACKGROUND AND AIM: Remnant cholesterol (RC) is substantially related to negative outcomes in cardiac patients. Patients with coexisting hypertension and heart failure (HF) often develop left ventricular hypertrophy (LVH) and have poor prognoses. This study investigated baseline RC levels and LV remodelling and patients' prognoses. METHODS AND RESULTS: Six hundred thirty consecutive individuals with hypertension and HF participated in this prospective trial from October 2018 to August 2020. Based on left ventricular mass index (LVMI), 560 those eligible were separated into LVH and non-LVH groups. Multiple linear regression and receiver operating characteristic (ROC) curves examined the RC and LV relationship. A Cox regression analysis was conducted to examine the predictive value of RC for clinical outcomes. The LVH group presented significantly elevated values of RC, triglyceride, and cholesterol and decreased high-density lipoprotein cholesterol (HDLC). The optimal cutoff value for RC to predict LV remodelling was 0.49. The subjects were observed for a median of 58 months, and 104 participants met the primary endpoint. The risk models involving the two Cox models were adjusted to incorporate confounding factors, which revealed that those with elevated baseline levels of RC were more susceptible to cardiovascular mortality, as shown by an increased hazard ratio. (HR: 1.91, 95% CI: 1.62-2.26 vs. HR: 1.75, 95% CI: 1.43-2.16, P < 0.001). CONCLUSIONS: RC is linked to LV remodelling in patients with hypertensive HF, with LVH having greater RC values. Moreover, patients with hypertensive HF who had a higher RC suffered from an increased risk of cardiovascular mortality. TRIAL REGISTRATION: NCT03727828, 21 Oct 2018.


Assuntos
Colesterol , Insuficiência Cardíaca , Hipertensão , Hipertrofia Ventricular Esquerda , Triglicerídeos , Humanos , Hipertrofia Ventricular Esquerda/sangue , Masculino , Feminino , Hipertensão/complicações , Hipertensão/sangue , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/complicações , Colesterol/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Prognóstico , Triglicerídeos/sangue , Remodelação Ventricular , Curva ROC , Modelos de Riscos Proporcionais , HDL-Colesterol/sangue , Fatores de Risco
16.
BMC Med Imaging ; 24(1): 262, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367333

RESUMO

BACKGROUND: The study aimed to identify the optimal model for predicting rectal cancer liver metastasis (RCLM). This involved constructing various prediction models to aid clinicians in early diagnosis and precise decision-making. METHODS: A retrospective analysis was conducted on 193 patients diagnosed with rectal adenocarcinoma were randomly divided into training set (n = 136) and validation set (n = 57) at a ratio of 7:3. The predictive performance of three models was internally validated by 10-fold cross-validation in the training set. Delineation of the tumor region of interest (ROI) was performed, followed by the extraction of radiomics features from the ROI. The least absolute shrinkage and selection operator (LASSO) regression algorithm and multivariate Cox analysis were employed to reduce the dimensionality of radiomics features and identify significant features. Logistic regression was employed to construct three prediction models: clinical, radiomics, and combined models (radiomics + clinical). The predictive performance of each model was assessed and compared. RESULTS: KRAS mutation emerged as an independent predictor of liver metastasis, yielding an odds ratio (OR) of 8.296 (95%CI: 3.471-19.830; p < 0.001). 5 radiomics features will be used to construct radiomics model. The combined model was built by integrating radiomics model with clinical model. In both the training set (AUC:0.842, 95%CI: 0.778-0.907) and the validation set (AUC: 0.805; 95%CI: 0.692-0.918), the AUCs for the combined model surpassed those of the radiomics and clinical models. CONCLUSIONS: Our study reveals that KRAS mutation stands as an independent predictor of RCLM. The radiomics features based on MR play a crucial role in the evaluation of RCLM. The combined model exhibits superior performance in the prediction of liver metastasis. CLINICAL TRIAL NUMBER: Not applicable.


Assuntos
Neoplasias Hepáticas , Imageamento por Ressonância Magnética , Mutação , Proteínas Proto-Oncogênicas p21(ras) , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/genética , Neoplasias Retais/patologia , Feminino , Masculino , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Imageamento por Ressonância Magnética/métodos , Idoso , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/genética , Adenocarcinoma/secundário , Adulto , Valor Preditivo dos Testes , Radiômica
17.
BMC Pulm Med ; 24(1): 295, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38914995

RESUMO

The notion of a constant relationship between resistance and capacitance (RC time) in the pulmonary circulation has been challenged by more recent research. The RC time can be obtained using either a simplified empirical approach or a semilogarithmic equation. Although direct curve-fit analysis is a feasible and ostensibly reference approach for RC analysis, it remains largely unexplored. We aimed to study the relationship between various RC methods in different states of pulmonary hemodynamics. Methods In total, 182 patients underwent clinically indicated right heart catheterization. The pressure curves were exported and processed using the MATLAB software. We calculated the RC time using the empirical method (RCEST), semilogarithmic approach (RCSL), and direct measurement of curve fit (RCFIT). Results Among 182 patients, 137 had pulmonary hypertension due to left heart disease (PH-LHD), 35 had pulmonary arterial hypertension (PAH), and 10 demonstrated normal hemodynamics (non-PH). RCEST consistently overestimated the RCFIT and RCSL measurements by a mean of 75%. With all three methods, the RC values were longer in the PAH (RCFIT = 0.36 ± 0.14 s) than in the PH-LHD (0.27 ± 0.1 s) and non-PH (0.27 ± 0.09 s) groups (p < 0.001). Although the RCSL and RCFIT values were similar among the three subgroups, they exhibited broad limits of agreement. Finally, the RCEST demonstrated a strong discriminatory ability (AUC = 0.86, p < 0.001, CI = 0.79-0.93) in identifying PAH. Conclusion RC time in PAH patients was substantially prolonged compared to that in PH-LHD and non-PH patients. The use of the empirical formula yielded systematic RC overestimation. In contrast, the semilogarithmic analysis provided reliable RC estimates, particularly for group comparisons.


Assuntos
Cateterismo Cardíaco , Hipertensão Pulmonar , Artéria Pulmonar , Humanos , Masculino , Feminino , Artéria Pulmonar/fisiopatologia , Pessoa de Meia-Idade , Idoso , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/diagnóstico , Resistência Vascular/fisiologia , Adulto , Hemodinâmica/fisiologia , Capacitância Vascular , Hipertensão Arterial Pulmonar/fisiopatologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-38678392

RESUMO

PURPOSE: Rotator cuff (RC) disorders are the most common cause of shoulder disability. The aim of this study was to quantify the evidence on the sex-related differences in RC repair. METHODS: A systematic review of the literature was performed in January 2023 in PubMed, Wiley Cochrane Library and Web of Science on research articles on humans with RC tears treated surgically. A meta-analysis was performed to compare results in men and women. The Downs and Black score and the modified Coleman methodology score (MCMS) were used to assess the retrieved studies. RESULTS: A total of 39,909 patients were enroled in the 401 studies analysed (45% women, 55% men). A trend toward more sex-balanced recruitment was observed over time. Only 4% of the studies on 1.5% of the documented patients presented disaggregated outcome data and were quantitatively analysed. A tendency for lower range of motion values after surgery was found for external shoulder rotation in women, with 39.9° ± 6.9° versus 45.3° ± 4.1° in men (p = 0.066). According to Downs and Black scores, four studies were good and 12 fair, with a main MCMS score of 69/100. CONCLUSION: There is a lack of awareness on the importance to document women- and men-specific data. Only 4% of the articles disaggregated data, and it was possible to analyse only 1.5% of the literature population, a sample which cannot be considered representative of all patients. The lack of disaggregated data is alarming and calls for action to better study men and women differences to optimise the management of RC tears. This will be necessary to provide sex-specific information that could be of clinical relevance when managing RC repair. LEVEL OF EVIDENCE: Level IV.

19.
Knee Surg Sports Traumatol Arthrosc ; 32(7): 1843-1853, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38651602

RESUMO

PURPOSE: Management of massive rotator cuff tears (MRCTs) remains debated, and various arthroscopic and open techniques have been described for their management. Nevertheless, the optimal strategy remains unclear. The present study evaluated the clinical results in patients managed arthroscopically for MRCTs augmented with the long head biceps tendon (LHBT) at a minimum 1-year follow-up, considering different type of tears, demographic data and number of torn tendons. METHODS: Patients treated in a secondary referral centre from January 2021 to April 2022 were enroled prospectively. Inclusion criteria were pain, inability to fully elevate the affected shoulder, irreparable tears and active and motivated patients. All patients were managed within 2 months from diagnosis in a single centre by the same surgeons. Preoperative shoulder radiographs and magnetic resonance imaging (MRI) were collected, and clinical assessment was also performed using the Numerical analogue scale (NAS), Constant score (CS) American Shoulder and Elbow Surgeons Shoulder Score (ASES). Tissue retraction and tendon fatty infiltration were evaluated using Patte and Fuchs scale, respectively. Clinical assessment was performed using the same scales at 3-6 months and 1-year follow-up. RESULTS: A total of 55 patients (31 female and 24 male) with a mean age of 60 ± 7.1 years were enroled for a mean follow-up of 18.2 ± 4.3 months. The mean preoperative NAS was 7.8 ± 0.6, CS was 20.5 ± 7.6 and ASES was 22.6 ± 9.2, increasing, respectively, to 0.3 ± 0.6, 91.5 ± 6.9 and 94.2 ± 6.7. No adverse side effects (infection, rejection, allergy) were reported during the study period. All patients were evaluated after surgery at 3 and 6 months and 1 year with statistically significant improvement for each score at the first and last follow-up (p < 0.05). CONCLUSIONS: The use of LHBT augmentation in patients with MRCTs in appropriately selected patients is safe and effective and can lead to pain relief and acceptable clinical outcomes. Furthermore, its use carries low donor site morbidity and is cost effective. Comparative studies, including randomised controlled trials, with other proposed techniques are needed to confirm these findings. LEVEL OF EVIDENCE: Level IV.


Assuntos
Artroscopia , Lesões do Manguito Rotador , Humanos , Masculino , Feminino , Lesões do Manguito Rotador/cirurgia , Lesões do Manguito Rotador/diagnóstico por imagem , Pessoa de Meia-Idade , Artroscopia/métodos , Estudos Prospectivos , Imageamento por Ressonância Magnética , Idoso , Resultado do Tratamento , Tendões/cirurgia , Tendões/transplante , Medição da Dor
20.
Genomics ; 115(4): 110645, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37230182

RESUMO

The processes driving ferroptosis and rotator cuff (RC) inflammation are yet unknown. The mechanism of ferroptosis and inflammation involved in the development of RC tears was investigated. The Gene Expression Omnibus database was used to obtain the microarray data relevant to the RC tears for further investigation. In this study, we created an RC tears rat model for in vivo experimental validation. For the additional function enrichment analysis, 10 hub ferroptosis-related genes were chosen to construct the correlation regulation network. In RC tears, it was discovered that genes related to hub ferroptosis and hub inflammatory response were strongly correlated. The outcomes of in vivo tests showed that RC tears were related to Cd68-Cxcl13, Acsl4-Sat1, Acsl3-Eno3, Acsl3-Ccr7, and Ccr7-Eno3 pairings in regulating ferroptosis and inflammatory response. Thus, our results show an association between ferroptosis and inflammation, providing a new avenue to explore the clinical treatment of RC tears.


Assuntos
Ferroptose , Lesões do Manguito Rotador , Ratos , Animais , Lesões do Manguito Rotador/genética , Lesões do Manguito Rotador/metabolismo , Ferroptose/genética , Receptores CCR7/metabolismo , Manguito Rotador/metabolismo , Inflamação/genética
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