Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 467
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
J Pathol ; 264(2): 186-196, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-39072750

RESUMO

Tumor immunological characterization includes evaluation of tumor-infiltrating lymphocytes (TILs) and programmed cell death protein ligand-1 (PD-L1) expression. This study investigated TIL distribution, its prognostic value, and PD-L1 expression in metastatic and matched primary tumors (PTs). Specimens from 550 pan-cancer patients of the SHIVA01 trial (NCT01771458) with available metastatic biopsy and 111 matched PTs were evaluated for TILs and PD-L1. Combined positive score (CPS), tumor proportion score (TPS), and immune cell (IC) score were determined. TILs and PD-L1 were assessed according to PT organ of origin, histological subtype, and metastatic biopsy site. We found that TIL distribution in metastases did not vary according to PT organ of origin, histological subtype, or metastatic biopsy site, with a median of 10% (range: 0-70). TILs were decreased in metastases compared to PT (20% [5-60] versus 10% [0-40], p < 0.0001). CPS varied according to histological subtype (p = 0.02) and biopsy site (p < 0.02). TPS varied according to PT organ of origin (p = 0.003), histological subtype (p = 0.0004), and metastatic biopsy site (p = 0.00004). TPS was higher in metastases than in PT (p < 0.0001). TILs in metastases did not correlate with overall survival. In conclusion, metastases harbored fewer TILs than matched PT, regardless of PT organ of origin, histological subtype, and metastatic biopsy site. PD-L1 expression increased with disease progression. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Antígeno B7-H1 , Linfócitos do Interstício Tumoral , Neoplasias , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno B7-H1/análise , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Biópsia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Linfócitos do Interstício Tumoral/metabolismo , Metástase Neoplásica , Neoplasias/diagnóstico , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Prognóstico , Estudos Cross-Over
2.
J Biol Chem ; 299(1): 102737, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36423682

RESUMO

BY-kinases (for bacterial tyrosine kinases) constitute a family of protein tyrosine kinases that are highly conserved in the bacterial kingdom and occur most commonly as essential components of multicomponent assemblies responsible for the biosynthesis, polymerization, and export of complex polysaccharides involved in biofilm or capsule formation. BY-kinase function has been attributed to a cyclic process involving formation of an oligomeric species, its disassembly into constituent monomers, and subsequent reassembly, depending on the overall phosphorylation level of a C-terminal cluster of tyrosine residues. However, the relationship of this process to the active/inactive states of the enzyme and the mechanism of its integration into the polysaccharide production machinery remain unclear. Here, we synthesize the substantial body of biochemical, cell-biological, structural, and computational data, acquired over the nearly 3 decades since the discovery of BY-kinases, to suggest means by which they fulfill their physiological function. We propose a mechanism involving temporal coordination of the assembly/disassembly process with the autokinase activity of the enzyme and its ability to be dephosphorylated by its counteracting phosphatase. We speculate that this temporal control enables BY-kinases to function as molecular timers that coordinate the diverse processes involved in the synthesis, polymerization, and export of complex sugar derivatives. We suggest that BY-kinases, which deploy distinctive catalytic domains resembling P-loop nucleoside triphosphatases, have uniquely adapted this ancient fold to drive functional processes through exquisite spatiotemporal control over protein-protein interactions and conformational changes. It is our hope that the hypotheses proposed here will facilitate future experiments targeting these unique protein kinases.


Assuntos
Proteínas de Bactérias , Monoéster Fosfórico Hidrolases , Proteínas Tirosina Quinases , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Polissacarídeos , Proteínas Tirosina Quinases/metabolismo , Tirosina/metabolismo , Proteínas de Bactérias/metabolismo
3.
Br J Haematol ; 204(6): 2468-2479, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38650379

RESUMO

Paroxysmal nocturnal haemoglobinuria (PNH) is a disorder resulting from erythrocyte membrane deficiencies caused by PIG-A gene mutations. While current treatments alleviate symptoms, they fail to address the underlying cause of the disease-the pathogenic PNH clones. In this study, we found that the expression of carbamoyl phosphate synthetase 1 (CPS1) was downregulated in PNH clones, and the level of CPS1 was negatively correlated with the proportion of PNH clones. Using PIG-A knockout K562 (K562 KO) cells, we demonstrated that CPS1 knockdown increased cell proliferation and altered cell metabolism, suggesting that CPS1 participates in PNH clonal proliferation through metabolic reprogramming. Furthermore, we observed an increase in the expression levels of the histone demethylase JMJD1C in PNH clones, and JMJD1C expression was negatively correlated with CPS1 expression. Knocking down JMJD1C in K562 KO cells upregulated CPS1 and H3K36me3 expression, decreased cell proliferation and increased cell apoptosis. Chromatin immunoprecipitation analysis further demonstrated that H3K36me3 regulated CPS1 expression. Finally, we demonstrated that histone demethylase inhibitor JIB-04 can suppressed K562 KO cell proliferation and reduced the proportion of PNH clones in PNH mice. In conclusion, aberrant regulation of the JMJD1C-H3K36me3-CPS1 axis contributes to PNH clonal proliferation. Targeting JMJD1C with a specific inhibitor unveils a potential strategy for treating PNH patients.


Assuntos
Proliferação de Células , Hemoglobinúria Paroxística , Histona Desmetilases com o Domínio Jumonji , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Animais , Camundongos , Células K562 , Hemoglobinúria Paroxística/patologia , Hemoglobinúria Paroxística/genética , Hemoglobinúria Paroxística/metabolismo , Masculino , Feminino , Apoptose , Reprogramação Metabólica , Oxirredutases N-Desmetilantes
4.
Appl Environ Microbiol ; 90(8): e0221023, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39072624

RESUMO

Quorum sensing (QS) orchestrates many bacterial behaviors, including virulence and biofilm formation, across bacterial populations. Nevertheless, the underlying mechanism by which QS regulates capsular polysaccharide (CPS)-dependent phage-bacterium interactions remains unclear. In this study, we report that QS upregulates the expression of CPS-dependent phage receptors, thus increasing phage adsorption and infection rates in Vibrio alginolyticus. We found that QS upregulated the expression of the ugd gene, leading to increased synthesis of Autographiviridae phage receptor CPS synthesis in V. alginolyticus. The signal molecule autoinducer-2 released by Vibrio from different sources can potentially enhance CPS-dependent phage infections. Therefore, our data suggest that inhibiting QS may reduce, rather than improve, the therapeutic efficacy of CPS-specific phages. IMPORTANCE: Phage resistance is a direct threat to phage therapy, and understanding phage-host interactions, especially how bacteria block phage infection, is essential for developing successful phage therapy. In the present study, we demonstrate for the first time that Vibrio alginolyticus uses quorum sensing (QS) to promote capsular polysaccharide (CPS)-specific phage infection by upregulating ugd expression, which is necessary for the synthesis of Autographiviridae phage receptor CPS. Although increased CPS-specific phage susceptibility is a novel trade-off mediated by QS, it results in the upregulation of virulence factors, promoting biofilm development and enhanced capsular polysaccharide production in V. alginolyticus. This suggests that inhibiting QS may improve the effectiveness of antibiotic treatment, but it may also reduce the efficacy of phage therapy.


Assuntos
Percepção de Quorum , Vibrio alginolyticus , Vibrio alginolyticus/virologia , Vibrio alginolyticus/fisiologia , Bacteriófagos/fisiologia , Bacteriófagos/genética , Homosserina/análogos & derivados , Homosserina/metabolismo , Cápsulas Bacterianas/metabolismo , Podoviridae/genética , Podoviridae/fisiologia , Biofilmes/crescimento & desenvolvimento , Polissacarídeos Bacterianos/metabolismo
5.
Rev Cardiovasc Med ; 25(1): 3, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39077657

RESUMO

Background: Transcatheter aortic valve replacement (TAVR) has become the dominant treatment for aortic valve disease. While TAVR safety has improved over time, concern remains over the occurrence of cerebrovascular accidents (CVA) secondary to device placement, which is associated with increased morbidity and mortality. The Sentinel Cerebral Protection System (CPS) was developed to reduce the risk of embolic strokes associated with debris produced during TAVR. Studies evaluating Sentinel CPS efficacy have produced conflicting results, and there is little understanding of which patients are selected for device placement in "real-world" settings. With no existing guidelines on device use, the purpose of this study was to describe and compare the characteristics of patients who receive CPS with those who do not in a "real-world" setting of consecutive TAVR patients and evaluate its impact on postoperative complications, namely stroke. Methods: This was a single-center, retrospective study of all patients undergoing TAVR between July 1, 2019, and December 31, 2020. Patient demographics, baseline, and perioperative characteristics were collected prospectively using the Society of Thoracic Surgeons (STS)/American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) Registry and our institution's TAVR database for analysis. Postoperative outcomes were assessed using primary endpoints of in-hospital/30-day stroke and the composite of death, stroke, and bleeding/vascular events at one-year. To adjust for baseline differences, a propensity score was developed including all factors that were different between groups, and Multivariate Cox Regression analysis was used to control for these differences. Patient follow-up was 97% complete at 12 months with 100% echocardiographic follow-up. Results: A total of 242 consecutive patients (57.9% male) were analyzed, with a mean age of 79.9 ± 9 years. Of these patients, 134 (55.4%) received the Sentinel CPS and 108 (44.6%) did not. Sentinel CPS patients were more likely to be male, not on dialysis, without prior CVA or pacemaker, had less severe chronic lung disease, and were lower operative risk compared to concurrent non-CPS patients. CPS patients were also found to have higher hemoglobin and albumin levels, lower creatinine, and were less likely to be on immunosuppressant therapy. The incidence of in-hospital/30-day stroke after TAVR did not differ between CPS and non-CPS patients (0.0% vs. 1.9%; p = 0.198). Unadjusted analyses at one-year showed a lower occurrence of the composite endpoint in CPS patients compared non-CPS patients (8.3% vs. 17.0%; p = 0.034). After adjustment, the hazard ratio (Adj HR) for the CPS group was no longer significantly associated with a lower composite endpoint (Adj HR = 0.609, 95% CI 0.244-1.523; p = 0.289). Both unadjusted (p = 0.233) and adjusted (p = 0.132) analyses showed no difference in the incidence of stroke at one-year. Conclusions: Our study demonstrates that in a "real-world" setting, the Sentinel CPS device is more likely to be used in healthier and less complex patients. In analyses adjusted for illness severity and patient complexity, CPS use did not have a significant effect on the incidence of in-hospital/30-day stroke or the composite endpoint of death, stroke, and bleeding/vascular events at one-year.

6.
Gynecol Oncol ; 184: 57-66, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38295614

RESUMO

Over recent years, there has been significant progress in the development of immunotherapeutic molecules designed to block the PD-1/PD-L1 axis. These molecules have demonstrated their ability to enhance the immune response by prompting T cells to identify and suppress neoplastic cells. PD-L1 is a type 1 transmembrane protein ligand expressed on T lymphocytes, B lymphocytes, and antigen-presenting cells and is considered a key inhibitory checkpoint involved in cancer immune regulation. PD-L1 immunohistochemical expression in gynecological malignancies is extremely variable based on tumor stage and molecular subtypes. As a result, a class of monoclonal antibodies targeting the PD-1 receptor and PD-L1, known as immune checkpoint inhibitors, has found successful application in clinical settings. In clinical practice, the standard method for identifying suitable candidates for immune checkpoint inhibitor therapy involves immunohistochemical assessment of PD-L1 expression in neoplastic tissues. The most commonly used PD-L1 assays in clinical trials are SP142, 28-8, 22C3, and SP263, each of which has been rigorously validated on specific platforms. Gynecologic cancers encompass a wide spectrum of malignancies originating from the ovaries, uterus, cervix, and vulva. These neoplasms have shown variable response to immunotherapy which appears to be influenced by genetic and protein expression profiles, including factors such as mismatch repair status, tumor mutational burden, and checkpoint ligand expression. In the present paper, an extensive review of PD-L1 expression in various gynecologic cancer types is discussed, providing a guide for their pathological assessment and reporting.


Assuntos
Antígeno B7-H1 , Neoplasias dos Genitais Femininos , Inibidores de Checkpoint Imunológico , Humanos , Feminino , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Neoplasias dos Genitais Femininos/patologia , Neoplasias dos Genitais Femininos/imunologia , Neoplasias dos Genitais Femininos/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/metabolismo
7.
Vet Res ; 55(1): 17, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321502

RESUMO

Streptococcus suis is a gram-positive bacterium that causes meningitis, septicemia, endocarditis, and other disorders in pigs and humans. We obtained 42 and 50 S. suis isolates from lesions of porcine endocarditis and palatine tonsils, respectively, of clinically healthy pigs in Japan; we then determined their sequence types (STs) by multilocus sequence typing (MLST), cps genotypes, serotypes, and presence of classical major virulence-associated marker genes (mrp, epf, and sly). The 42 isolates from endocarditis lesions were assigned to a limited number of STs and clonal complexes (CCs). On the other hand, the 50 isolates from tonsils were diverse in these traits and seemingly in the degree of virulence, suggesting that tonsils can accommodate a variety of S. suis isolates. The goeBURST full algorithm using tonsil isolates obtained in this study and those retrieved from the database showed that major CCs as well as many other clusters were composed of isolates originating from different countries, and some of the STs were very similar to each other despite the difference in country of origin. These findings indicate that S. suis with not only different but also similar mutations in the genome have survived in tonsils independently across different geographical locations. Therefore, unlike the lesions of endocarditis, the tonsils of pigs seemingly accommodate various S. suis lineages. The present study suggests that S. suis acquired its diversity by natural mutations during colonization and persistence in the tonsils of pigs.


Assuntos
Endocardite , Infecções Estreptocócicas , Streptococcus suis , Doenças dos Suínos , Humanos , Suínos , Animais , Tipagem de Sequências Multilocus/veterinária , Tonsila Palatina/microbiologia , Streptococcus suis/genética , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Doenças dos Suínos/microbiologia , Endocardite/veterinária
8.
BMC Pediatr ; 24(1): 539, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39174957

RESUMO

BACKGROUND: Carbamoyl phosphate synthetase 1 (CPS1) deficiency (OMIM 237300), an autosomal recessive rare and severe urea cycle disorder, is associated with hyperammonemia and high mortality. METHODS: Herein we present 12 genetic variants identified in seven clinically well-characterized Chinese patients with CPS1 deficiency who were admitted to the Children's Medical Center of Peking University First Hospital from September 2014 to August 2023. RESULTS: Seven patients (two male and five female patients including two sisters) experienced symptoms onset between 2 days and 13 years of age, and they were diagnosed with CPS1 deficiency between 2 months and 20 years. Peak blood ammonia levels ranged from 160 to 1,000 µmol/L. Three patients showed early-onset CPS1 deficiency, with only one surviving after treatment with sodium phenylbutyrate, N-carbamoyl-L-glutamate, and liver transplantation at 4 months, showing a favorable outcome. The remaining four patients had late-onset CPS1 deficiency, presenting with mental retardation, psychiatric symptoms, and self-selected low-protein diets. Among the 12 CPS1 variants identified in these patients, 10 were novel, with all patients exhibiting compound heterozygosity for CPS1 mutant alleles. Seven variants (c.149T > C, c.616 A > T, c.1145 C > T, c.1294G > A, c.3029 C > T, c.3503 A > T, and c.3793 C > T) resulted in single amino acid substitutions. Three frameshift variations (c.2493del, c.3067dup, and c.3241del) were identified, leading to enzyme truncation. One mutation (c.3506_3508del) caused an in-frame single amino acid deletion, while another (c.2895 + 2T > C) resulted in aberrant splicing. CONCLUSIONS: Except for two known variants, all other variants were identified as novel. No hotspot variants were observed among the patients. Our data contribute to expanding the mutation spectrum of CPS1.


Assuntos
Carbamoil-Fosfato Sintase (Amônia) , Doença da Deficiência da Carbamoil-Fosfato Sintase I , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem , Carbamoil-Fosfato Sintase (Amônia)/genética , Doença da Deficiência da Carbamoil-Fosfato Sintase I/genética , China , População do Leste Asiático/genética , Mutação
9.
Sensors (Basel) ; 24(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793967

RESUMO

The arising of the Cyber-Physical Systems' vision and concepts drives technological evolution toward a new architectural design for the infrastructure of an environment referred to as a Smart Environment. This perspective alters the way systems within Smart City landscapes are conceived, designed, and ultimately realized. Modular architecture, resource-sharing techniques, and precise deployment approaches (such as microservices-oriented or reliant on the FaaS paradigm) serve as the cornerstones of a Smart City cognizant of multiple Cyber-Physical Systems composing it. This paper presents a framework integrating Digital Decisioning, encompassing the automated combination of human-derived knowledge and data-derived knowledge (e.g., business rules and machine learning), to enhance decision-making processes and application definition within the Smart City context.

10.
Sensors (Basel) ; 24(3)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38339566

RESUMO

In recent years, the problem of cyber-physical systems' remote state estimations under eavesdropping attacks have been a source of concern. Aiming at the existence of eavesdroppers in multi-system CPSs, the optimal attack energy allocation problem based on a SINR (signal-to-noise ratio) remote state estimation is studied. Assume that there are N sensors, and these sensors use a shared wireless communication channel to send their state measurements to the remote estimator. Due to the limited power, eavesdroppers can only attack M channels out of N channels at most. Our goal is to use the Markov decision processes (MDP) method to maximize the eavesdropper's state estimation error, so as to determine the eavesdropper's optimal attack allocation. We propose a backward induction algorithm which uses MDP to obtain the optimal attack energy allocation strategy. Compared with the traditional induction algorithm, this algorithm has lower computational cost. Finally, the numerical simulation results verify the correctness of the theoretical analysis.

11.
Sensors (Basel) ; 24(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38339656

RESUMO

This article presents a novel hardware-assisted distributed ledger-based solution for simultaneous device and data security in smart healthcare. This article presents a novel architecture that integrates PUF, blockchain, and Tangle for Security-by-Design (SbD) of healthcare cyber-physical systems (H-CPSs). Healthcare systems around the world have undergone massive technological transformation and have seen growing adoption with the advancement of Internet-of-Medical Things (IoMT). The technological transformation of healthcare systems to telemedicine, e-health, connected health, and remote health is being made possible with the sophisticated integration of IoMT with machine learning, big data, artificial intelligence (AI), and other technologies. As healthcare systems are becoming more accessible and advanced, security and privacy have become pivotal for the smooth integration and functioning of various systems in H-CPSs. In this work, we present a novel approach that integrates PUF with IOTA Tangle and blockchain and works by storing the PUF keys of a patient's Body Area Network (BAN) inside blockchain to access, store, and share globally. Each patient has a network of smart wearables and a gateway to obtain the physiological sensor data securely. To facilitate communication among various stakeholders in healthcare systems, IOTA Tangle's Masked Authentication Messaging (MAM) communication protocol has been used, which securely enables patients to communicate, share, and store data on Tangle. The MAM channel works in the restricted mode in the proposed architecture, which can be accessed using the patient's gateway PUF key. Furthermore, the successful verification of PUF enables patients to securely send and share physiological sensor data from various wearable and implantable medical devices embedded with PUF. Finally, healthcare system entities like physicians, hospital admin networks, and remote monitoring systems can securely establish communication with patients using MAM and retrieve the patient's BAN PUF keys from the blockchain securely. Our experimental analysis shows that the proposed approach successfully integrates three security primitives, PUF, blockchain, and Tangle, providing decentralized access control and security in H-CPS with minimal energy requirements, data storage, and response time.


Assuntos
Inteligência Artificial , Blockchain , Humanos , Segurança Computacional , Computadores , Atenção à Saúde/métodos
12.
Molecules ; 29(17)2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39275107

RESUMO

Bacillus anthracis is a Gram-positive bacterium that can cause acute infection and anthracnose, which is a serious concern for human health. Determining Bacillus anthracis through its spore biomarker dipicolinic acid (DPA) is crucial, and there is a strong need for a method that is rapid, sensitive, and selective. Here, we created Eu(III)-coordination polymers (Eu-CPs) with surfaces that have abundant carboxyl and hydroxyl groups. This was achieved by using citric acid and europium nitrate hexahydrate as precursors in a straightforward one-pot hydrothermal process. These Eu-CPs were then successfully utilized for highly sensitive DPA determination. The fluorescence (FL) emission of Eu-CPs, which is typically weak due to the coordination of Eu(III) with water molecules, was significantly enhanced in the presence of DPA. This enhancement is attributed to the competitive binding between DPA's carboxyl or hydroxyl groups and water molecules. As a result, the absorbed energy of DPA, when excited by 280 nm ultraviolet light, is transferred to Eu-CPs through an antenna effect. This leads to the emission of the characteristic red fluorescence of Eu3+ at 618 nm. A strong linear relationship was observed between the enhanced FL intensity and DPA concentration in the range of 0.5-80 µM. This relationship allowed for a limit of detection (LOD) of 15.23 nM. Furthermore, the Eu-CPs we constructed can effectively monitor the release of DPA from Bacillus subtilis spores, thereby further demonstrating the potential significance of this strategy in the monitoring and management of anthrax risk. This highlights the novelty of this approach in practical applications, provides a valuable determination technique for Bacillus anthracis, and offers insights into the development cycle of microorganisms.


Assuntos
Bacillus anthracis , Európio , Ácidos Picolínicos , Polímeros , Ácidos Picolínicos/química , Európio/química , Polímeros/química , Espectrometria de Fluorescência/métodos , Complexos de Coordenação/química
13.
Eur J Neurosci ; 58(8): 3838-3858, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37667595

RESUMO

Despite the importance of prosodic processing in utterance parsing, a majority of studies investigating boundary localization in a second language focus on word segmentation. The goal of the present study was to investigate the parsing of phrase boundaries in first and second languages from different prosodic typologies (stress-timed vs. syllable-timed). Fifty English-French bilingual adults who varied in native language (French or English) and second language proficiency listened to English and French utterances with different prosodic structures while event-related brain potentials were recorded. The utterances were built around target words presented either in phrase-final position (bearing phrase-final lengthening) or in penultimate position. Each participant listened to both English and French stimuli, providing data in their native language (used as reference) and their second language. Target words in phrase-final position elicited closure positive shifts across listeners in both languages, regardless of the language-specific acoustic cues associated with phrase-final lengthening (shorter phrase-final lengthening in English compared to French). Interestingly, directional effects were observed, where learning to parse English as a second language in a native-like manner seemed to require a higher proficiency level than learning to parse French as a second language. This pattern of results supports the idea that L2 listeners need to learn to recognize L2-specific phrase-final lengthening regardless of the apparent similarity across languages and that some language combinations might present greater challenges than others.

14.
J Clin Microbiol ; 61(4): e0002423, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36971549

RESUMO

Streptococcus pneumoniae can produce a wide breadth of antigenically diverse capsule types, a fact that poses a looming threat to the success of vaccines that target pneumococcal polysaccharide (PS) capsule. Yet, many pneumococcal capsule types remain undiscovered and/or uncharacterized. Prior sequence analysis of pneumococcal capsule synthesis (cps) loci suggested the existence of capsule subtypes among isolates identified as "serotype 36" according to conventional capsule typing methods. We discovered these subtypes represent two antigenically similar but distinguishable pneumococcal capsule serotypes, 36A and 36B. Biochemical analysis of their capsule PS structure reveals that both have the shared repeat unit backbone [→5)-α-d-Galf-(1→1)-d-Rib-ol-(5→P→6)-ß-d-ManpNAc-(1→4)-ß-d-Glcp-(1→] with two branching structures. Both serotypes have a ß-d-Galp branch to Ribitol. Serotypes 36A and 36B differ by the presence of a α-d-Glcp-(1→3)-ß-d-ManpNAc or α-d-Galp-(1→3)-ß-d-ManpNAc branch, respectively. Comparison of the phylogenetically distant serogroup 9 and 36 cps loci, which all encode this distinguishing glycosidic bond, revealed that the incorporation of Glcp (in types 9N and 36A) versus Galp (in types 9A, 9V, 9L, and 36B) is associated with the identity of four amino acids in the cps-encoded glycosyltransferase WcjA. Identifying functional determinants of cps-encoded enzymes and their impact on capsule PS structure is key to improving the resolution and reliability of sequencing-based capsule typing methods and discovering novel capsule variants indistinguishable by conventional serotyping methods.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Humanos , Sorogrupo , Reprodutibilidade dos Testes , Sorotipagem , Polissacarídeos , Vacinas Pneumocócicas , Cápsulas Bacterianas/química
15.
Mod Pathol ; 36(5): 100128, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36889057

RESUMO

The assessment of the expression of programmed cell death ligand-1 (PD-L1) using immunohistochemistry (IHC) has been controversial since its introduction. The methods of assessment and the range of assays and platforms contribute to confusion. Perhaps the most challenging aspect of PD-L1 IHC is the combined positive score (CPS) method of interpretation of IHC results. Although the CPS method is prescribed for more indications than any other PD-L1 scoring system, its reproducibility has never been rigorously assessed. In this study, we collected a series of 108 gastric or gastroesophageal junction cancer cases, stained them using the Food and Drug Administration-approved 22C3 assay, scanned them, and then circulated them to 14 pathologists at 13 institutions for the assessment of interpretative concordance for the CPS system. We found that higher cut points (10 or 20) performed better than a CPS of <1 or >1. We used the Observers Needed to Evaluate Subjective Tests algorithm to assess how the CPS system might perform in the real-world setting and found that the cut points of <1 or >1 showed an overall percent agreement of only 30% among the pathologist raters, with a plateau occurring at 8 raters. The raters performed better at higher cut points. However, the best cut point of <20 versus that of >20 was still disappointing, with a plateau at an overall percent agreement of 70% (at 7 raters). Although there is no ground truth for CPS, we compared the score with quantitative messenger RNA measurement and showed no relationship between the score (at any cut point) and messenger RNA amount. In summary, we showed that CPS shows high subjective variability among pathologist readers and is likely to perform poorly in the real-world setting. This system may be the root cause of the poor specificity and relatively low predictive value of IHC companion diagnostic tests for PD-1 axis therapies that use the CPS system.


Assuntos
Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Apoptose , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Junção Esofagogástrica/patologia , Imuno-Histoquímica , Ligantes , Patologistas , Reprodutibilidade dos Testes , Neoplasias Gástricas/diagnóstico
16.
Mod Pathol ; 36(5): 100154, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36925069

RESUMO

Reliable, reproducible methods to interpret programmed death ligand-1 (PD-L1) expression on tumor cells (TC) and immune cells (IC) are needed for pathologists to inform decisions associated with checkpoint inhibitor therapies. Our international study compared interpathologist agreement of PD-L1 expression using the combined positive score (CPS) under standardized conditions on samples from patients with gastric/gastroesophageal junction/esophageal adenocarcinoma. Tissue sections from 100 adenocarcinoma pretreatment biopsies were stained in a single laboratory using the PD-L1 immunohistochemistry 28-8 and 22C3 (Agilent) pharmDx immunohistochemical assays. PD-L1 CPS was evaluated by 12 pathologists on scanned whole slide images of these biopsies before and after a 2-hour CPS training session by Agilent. Additionally, pathologists determined PD-L1-positive TC, IC, and total viable TC on a single tissue fragment from 35 of 100 biopsy samples. Scoring agreement among pathologists was assessed using the intraclass correlation coefficient (ICC). Interobserver variability for CPS for 100 biopsies was high, with only fair agreement among pathologists both pre- (range, 0.45-0.55) and posttraining (range, 0.56-0.57) for both assays. For the 35 single biopsy samples, poor/fair agreement was also observed for the total number of viable TC (ICC, 0.09), number of PD-L1-positive IC (ICC, 0.19), number of PD-L1-positive TC (ICC, 0.54), and calculated CPS (ICC, 0.14), whereas calculated TC score (positive TC/total TC) showed excellent agreement (ICC, 0.82). Retrospective histologic review of samples with the poorest interpathologist agreement revealed the following as possible confounding factors: (1) ambiguous identification of positively staining stromal cells, (2) faint or variable intensity of staining, (3) difficulty in distinguishing membranous from cytoplasmic tumor staining, and (4) cautery and crush artifacts. These results emphasize the need for objective techniques to standardize the interpretation of PD-L1 expression when using the CPS methodology on gastric/gastroesophageal junction cancer biopsies to accurately identify patients most likely to benefit from immune checkpoint inhibitor therapy.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Humanos , Antígeno B7-H1/metabolismo , Estudos Retrospectivos , Variações Dependentes do Observador , Patologistas , Biomarcadores Tumorais , Adenocarcinoma/patologia , Junção Esofagogástrica/metabolismo , Junção Esofagogástrica/patologia , Neoplasias Gástricas/patologia
17.
Histopathology ; 82(6): 826-836, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36694277

RESUMO

BACKGROUND AND AIMS: In gastric cancer (GC), HER2 was the first biomarker for guided therapy registered for clinical use. Considering the recent approvals of immune check-point blockade (ICB) in gastro-oesophageal cancers, testing for mismatch repair deficiency (dMMR), Epstein-Barr virus (EBV) and PD-L1 combined positive score (CPS) is becoming increasingly important. Here we describe a real-world cohort on biomarker assessment in GC patients. METHODS: Patients diagnosed with GC between 2017 and 2021 were included. Biomarker results were retrieved from electronic patient files. PD-L1 CPS was determined retrospectively on dMMR and EBV-positive (EBV+) tumours. Data on genomic sequencing were analysed separately. RESULTS: Of 363 patients identified, 45% had metastatic disease. In 335 patients (92%) at least one biomarker was tested. The prevalence of HER2+, dMMR and EBV+ tumours was 10% (32 of 319), 7% (20 of 294) and 1% (three of 235), respectively. Of the dMMR and EBV+ tumours, 95% had a PD-L1 CPS ≥ 5. Therapeutic strategy was adjusted in 31 of 55 patients and consisted of anti-HER2 therapies as well as ICB in clinical trials. Genomic alterations were found in 44 of 60 tested patients. TP53 (73%) and PIK3CA (20%) mutations were most common, followed by KRAS mutations (11%) and amplifications (11%). CONCLUSIONS: In this real-world cohort, testing for HER2, dMMR and EBV status affected treatment decisions in 56% of the patients. Although most dMMR and EBV+ tumours had a PD-L1 CPS ≥ 5, not all patients with a high probability of treatment response are identified. Based on these results, a stepwise diagnostic strategy is proposed.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/genética , Biomarcadores Tumorais/genética , Estudos Retrospectivos , Antígeno B7-H1/genética
18.
Toxicol Appl Pharmacol ; 461: 116401, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36706924

RESUMO

Chlorophenols (CPs) are widespread pollutants in nature. CPs have raised significant concern due to their potential hepatotoxic effects on humans. This research aimed to ascertain the inhibitory potential of eleven CPs (2-CP, 3-CP, 4-CP, 2,4-DCP, 2,3,4-TCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,5-TeCP, 2,3,4,6-TeCP, 2,3,5,6-TeCP, and PCP) on nine human CYP isoforms (CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4). The CPs that inhibit the activity of CYP isoforms were detected with human liver microsomes (HLM) using a cocktail approach in vitro. The results demonstrated that trichlorophenols, tetrachlorophenols, and PCP strongly inhibited CYP2C8 and CYP2C9. The half inhibition concentration (IC50) value of 2,3,4,6-TeCP and PCP for CYP2C8 inhibition was 27.3 µM and 12.3 µM, respectively. The IC50 for the inhibition of 2,4,6-TCP, 2,3,4,6-TeCP and PCP towards CYP2C9 were calculated to be 30.3 µM, 5.8 µM and 2.2 µM, respectively. 2,3,4,6-TeCP, and PCP exhibited non-competitive inhibition towards CYP2C8. 2,4,6-TCP, 2,3,4,6-TeCP, and PCP exhibited competitive inhibition towards CYP2C9. The inhibition kinetics parameters (Ki) were 51.51 µM, 22.28 µM, 37.86 µM, 7.27 µM, 0.68 µM for 2,3,4,6-TeCP-CYP2C8, PCP-CYP2C8, 2,4,6-TCP-CYP2C9, 2,3,4,6-TeCP-CYP2C9, PCP-CYP2C9, respectively. This study also defined clear structure-activity relationships (SAR) of CPs on CYP2C8, supported by molecular docking studies. Overall, CPs were found to cause inhibitory effects on CYP isoforms in vitro, and this finding may provide a basis for CPs focused on CYP isoforms inhibition endpoints.


Assuntos
Clorofenóis , Inibidores das Enzimas do Citocromo P-450 , Humanos , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP2C9/farmacologia , Simulação de Acoplamento Molecular , Inibidores das Enzimas do Citocromo P-450/toxicidade , Sistema Enzimático do Citocromo P-450 , Microssomos Hepáticos , Clorofenóis/toxicidade
19.
BMC Cancer ; 23(1): 817, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658290

RESUMO

INTRODUCTION: Immune checkpoint inhibitors have revolutionized the treatment of patients with advanced urothelial carcinoma (UC) in the frontline and relapsed settings. Lebanon has one of the highest incidence of UC worldwide, yet no data exists regarding the expression of PD-L1 by Combined Positive Score (CPS) in advanced disease. METHODS: We reviewed all patients treated at our institution for high grade UC, stage pT2 and above, between January 2017 and March 2021. We assessed the expression of PD-L1 by immunohistochemistry using 22C3 clone, and analyzed the association between PD-L1 expression and clinicopathological characteristics. PD-L1 positivity was defined as CPS score ≥ 10. RESULTS: A total of 101 patients with advanced UC were included, with a median age of 71 years (range, 38 to 96 years); 78% were ever-smokers. Ninety-three of 101 patients (92%) had conventional UC and 43 patients (43%) had positive PD-L1 expression, with 12 patients having CPS of 100. The analysis by molecular subtype showed that patients with maximal CPS of 100 were enriched in "basal" molecular subtype. However, no association was found between PD-L1 expression (positive versus negative) and clinicopathological characteristics. CONCLUSION: The positivity of PD-L1 expression as assessed by CPS using the 22C3 clone in our population was almost comparable to the results reported in the occidental literature. Therefore, PD-L1 expression, as a potential predictor of response to immunotherapy, concerns the same percentage of the Lebanese UC patients.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-H1/genética , Músculos , Instalações de Saúde
20.
J Inherit Metab Dis ; 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38069502

RESUMO

An increasing number of women with urea cycle disorders (UCDs) are reaching child-bearing age and becoming pregnant. Improved diagnostics and increased awareness of inherited metabolic diseases has also led to more previously undetected women being diagnosed with a UCD during or shortly after pregnancy. Pregnancy increases the risk of acute metabolic decompensation with hyperammonemia-which can occur in any trimester, and/or the postpartum period, and may lead to encephalopathy, psychosis, coma, and even death, if not diagnosed promptly and treated appropriately. There are also (theoretical) concerns that a maternal UCD, or its treatment, may cause potential risks for the unborn child. Currently evidence on management and outcome of pregnancies in UCDs is limited to case reports and there are no clear guidelines. In order to inform management and investigate outcomes of pregnancies in women with a UCD, we performed a retrospective review of published cases and analyzed data collected from an international online survey. We conclude that, although risk during the intra- and postpartum period exists, multidisciplinary management by an experienced team and a prospective plan usually result in successful pregnancy, labor, delivery, and postpartum period. No deaths were reported in mothers managed accordingly. With the exception of male neonates with Ornithine Transcarbamylase deficiency, the clinical outcome of children born to mothers with UCDs appears positive, although follow-up is limited. The outcome for women presenting with a first acute metabolic decompensation during pregnancy or postpartum is less favorable. Deaths were associated with diagnostic delay/late management of hyperammonemia in previously undiagnosed women.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA