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1.
mBio ; : e0335123, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953356

RESUMEN

Candida albicans causes millions of mucosal infections in humans annually. Hyphal overgrowth on mucosal surfaces is frequently associated with tissue damage caused by candidalysin, a secreted peptide toxin that destabilizes the plasma membrane of host cells thereby promoting disease and immunopathology. Candidalysin was first identified in C. albicans strain SC5314, but recent investigations have revealed candidalysin "variants" of differing amino acid sequence in isolates of C. albicans, and the related species C. dubliniensis, and C tropicalis, suggesting that sequence variation among candidalysins may be widespread in natural populations of these Candida species. Here, we analyzed ECE1 gene sequences from 182 C. albicans isolates, 10 C. dubliniensis isolates, and 78 C. tropicalis isolates and identified 10, 3, and 2 candidalysin variants in these species, respectively. Application of candidalysin variants to epithelial cells revealed differences in the ability to cause cellular damage, changes in metabolic activity, calcium influx, MAPK signalling, and cytokine secretion, while biophysical analyses indicated that variants exhibited differences in their ability to interact with and permeabilize a membrane. This study identifies candidalysin variants with differences in biological activity that are present in medically relevant Candida species. IMPORTANCE: Fungal infections are a significant burden to health. Candidalysin is a toxin produced by Candida albicans that damages host tissues, facilitating infection. Previously, we demonstrated that candidalysins exist in the related species C. dubliniensis and C. tropicalis, thereby identifying these molecules as a toxin family. Recent genomic analyses have highlighted the presence of a small number of candidalysin "variant" toxins, which have different amino acid sequences to those originally identified. Here, we screened genome sequences of isolates of C. albicans, C. dubliniensis, and C. tropicalis and identified candidalysin variants in all three species. When applied to epithelial cells, candidalysin variants differed in their ability to cause damage, activate intracellular signaling pathways, and induce innate immune responses, while biophysical analysis revealed differences in the ability of candidalysin variants to interact with lipid bilayers. These findings suggest that intraspecies variation in candidalysin amino acid sequence may influence fungal pathogenicity.

2.
BMJ Open ; 14(4): e083550, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38663923

RESUMEN

OBJECTIVES: Glucagon-like peptide 1 receptor agonists (GLP1-RA) are indicated for the treatment of type 2 diabetes and more recently for weight loss. The aim of this study was to assess the risks associated with GLP1-RA exposure during early pregnancy. DESIGN: This multicentre, observational prospective cohort study compared pregnancy outcomes in women exposed to GLP1-RA in early pregnancy either for diabetes or obesity treatment with those in two reference groups: (1) women with diabetes exposed to at least one non-GLP1-RA antidiabetic drug during the first trimester and (2) a reference group of overweight/obese women without diabetes, between 2009 and 2022. SETTING: Data were collected from the databases of six Teratology Information Services. PARTICIPANTS: This study included 168 pregnancies of women exposed to GLP1-RA during the first trimester, alongside a reference group of 156 pregnancies of women with diabetes and 163 pregnancies of overweight/obese women. RESULTS: Exposure to GLP1-RA in the first trimester was not associated with a risk of major birth defects when compared with diabetes (2.6% vs 2.3%; adjusted OR, 0.98 (95% CI, 0.16 to 5.82)) or to overweight/obese (2.6% vs 3.9%; adjusted OR 0.54 (0.11 to 2.75)). For the GLP1-RA group, cumulative incidence for live births, pregnancy losses and pregnancy terminations was 59%, 23% and 18%, respectively. In the diabetes reference group, corresponding estimates were 69%, 26% and 6%, while in the overweight/obese reference group, they were 63%, 29% and 8%, respectively. Cox proportional cause-specific hazard models indicated no increased risk of pregnancy losses in the GLP1-RA versus the diabetes and the overweight/obese reference groups, in both crude and adjusted analyses. CONCLUSIONS: This study offers reassurance in cases of inadvertent exposure to GLP1-RA during the first trimester of pregnancy. Due to the limited sample size, larger studies are required to validate these findings.


Asunto(s)
Receptor del Péptido 1 Similar al Glucagón , Hipoglucemiantes , Obesidad , Resultado del Embarazo , Primer Trimestre del Embarazo , Humanos , Femenino , Embarazo , Estudios Prospectivos , Adulto , Receptor del Péptido 1 Similar al Glucagón/agonistas , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/efectos adversos , Resultado del Embarazo/epidemiología , Obesidad/epidemiología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Anomalías Inducidas por Medicamentos/epidemiología , Embarazo en Diabéticas/tratamiento farmacológico , Bases de Datos Factuales , Complicaciones del Embarazo/tratamiento farmacológico
3.
Nat Microbiol ; 9(3): 669-683, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38388771

RESUMEN

The opportunistic fungal pathogen Candida albicans damages host cells via its peptide toxin, candidalysin. Before secretion, candidalysin is embedded in a precursor protein, Ece1, which consists of a signal peptide, the precursor of candidalysin and seven non-candidalysin Ece1 peptides (NCEPs), and is found to be conserved in clinical isolates. Here we show that the Ece1 polyprotein does not resemble the usual precursor structure of peptide toxins. C. albicans cells are not susceptible to their own toxin, and single NCEPs adjacent to candidalysin are sufficient to prevent host cell toxicity. Using a series of Ece1 mutants, mass spectrometry and anti-candidalysin nanobodies, we show that NCEPs play a role in intracellular Ece1 folding and candidalysin secretion. Removal of single NCEPs or modifications of peptide sequences cause an unfolded protein response (UPR), which in turn inhibits hypha formation and pathogenicity in vitro. Our data indicate that the Ece1 precursor is not required to block premature pore-forming toxicity, but rather to prevent intracellular auto-aggregation of candidalysin sequences.


Asunto(s)
Proteínas Fúngicas , Micotoxinas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Candida albicans/metabolismo , Micotoxinas/metabolismo , Péptidos/farmacología , Péptidos/metabolismo
4.
Mol Ecol ; 33(3): e17230, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38078558

RESUMEN

Urbanization is a persistent and widespread driver of global environmental change, potentially shaping evolutionary processes due to genetic drift and reduced gene flow in cities induced by habitat fragmentation and small population sizes. We tested this prediction for the eastern grey squirrel (Sciurus carolinensis), a common and conspicuous forest-dwelling rodent, by obtaining 44K SNPs using reduced representation sequencing (ddRAD) for 403 individuals sampled across the species' native range in eastern North America. We observed moderate levels of genetic diversity, low levels of inbreeding, and only a modest signal of isolation-by-distance. Clustering and migration analyses show that estimated levels of migration and genetic connectivity were higher than expected across cities and forested areas, specifically within the eastern portion of the species' range dominated by urbanization, and genetic connectivity was less than expected within the western range where the landscape is fragmented by agriculture. Landscape genetic methods revealed greater gene flow among individual squirrels in forested regions, which likely provide abundant food and shelter for squirrels. Although gene flow appears to be higher in areas with more tree cover, only slight discontinuities in gene flow suggest eastern grey squirrels have maintained connected populations across urban areas in all but the most heavily fragmented agricultural landscapes. Our results suggest urbanization shapes biological evolution in wildlife species depending strongly on the composition and habitability of the landscape matrix surrounding urban areas.


Asunto(s)
Animales Salvajes , Metagenómica , Animales , Humanos , Población Urbana , Ecosistema , Sciuridae/genética
5.
Drug Saf ; 47(3): 227-236, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38114757

RESUMEN

INTRODUCTION AND OBJECTIVE: The ConcePTION project aims to improve the way medication use during pregnancy is studied. This includes exploring the possibility of developing a distributed data processing and analysis infrastructure using a common data model that could form a foundational platform for future surveillance and research. A prerequisite would be that data from various data access providers (DAPs) can be harmonised according to an agreed set of standard rules concerning the structure and content of the data. To do so, a reference framework of core data elements (CDEs) recommended for primary data studies on drug safety during pregnancy was previously developed. The aim of this study was to assess the ability of several public and private DAPs using different primary data sources focusing on multiple sclerosis, as a pilot, to map their respective data variables and definitions with the CDE recommendations framework. METHODS: Four pregnancy registries (Gilenya, Novartis; Aubagio, Sanofi; the Organization of Teratology Information Specialists [OTIS]; Aubagio, Sanofi; the Dutch Pregnancy Drug Register, Lareb), two enhanced pharmacovigilance programmes (Gilenya PRIM, Novartis; MAPLE-MS, Merck Healthcare KGaA) and four Teratology Information Services (UK TIS, Jerusalem TIS, Zerifin TIS, Swiss TIS) participated in the study. The ConcePTION primary data source CDE includes 51 items covering administrative functions, the description of pregnancy, maternal medical history, maternal illnesses arising in pregnancy, delivery details, and pregnancy and infant outcomes. For each variable in the CDE, the DAPs identified whether their variables were: identical to the one mentioned in the CDE; derived; similar but with a divergent definition; or not available. RESULTS: The majority of the DAP data variables were either directly taken (85%, n = 305/357, range 73-94% between DAPs) or derived by combining different variables (12%, n = 42/357, range 0-24% between DAPs) to conform to the CDE variables and definitions. For very few of the DAP variables, alignment with the CDE items was not possible, either because of divergent definitions (1%, n = 3/357, range 0-2% between DAPs) or because the variables were not available (2%, n = 7/357, range 0-4% between DAPs). CONCLUSIONS: Data access providers participating in this study presented a very high proportion of variables matching the CDE items, indicating that alignment of definitions and harmonisation of data analysis by different stakeholders to accelerate and strengthen pregnancy pharmacovigilance safety data analyses could be feasible.


Asunto(s)
Crotonatos , Clorhidrato de Fingolimod , Hidroxibutiratos , Nitrilos , Toluidinas , Embarazo , Femenino , Humanos , Recolección de Datos , Sistema de Registros
6.
Acta Psychiatr Scand ; 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110225

RESUMEN

OBJECTIVE: In recent years, safety concerns about modafinil exposure during pregnancy have emerged. In particular, increased risks for major congenital anomalies (MCA) and impaired fetal growth were reported, although study results were conflicting. Our investigation aims to examine previously reported safety signals. METHOD: Multicenter case series based on data from 18 Teratology Information Services from 12 countries. Modafinil exposed pregnancies with an estimated date of birth before August 2019 were included in this study. For prospectively ascertained pregnancies, cumulative incidences of pregnancy outcomes, rate of nonchromosomal MCA in first trimester exposed pregnancies and percentiles of neonatal/infant weight and head circumference (HC) were calculated. Potential dose-dependent effects on fetal growth were explored by linear regression models. Retrospectively ascertained cases were screened for pattern of MCA and other adverse events. RESULTS: One hundred and seventy-five prospectively ascertained cases were included, of which 173 were exposed at least during the first trimester. Cumulative incidences for live birth, spontaneous abortion and elective termination of pregnancy were 76.9% (95% CI, 68.0%-84.8%), 9.3% (95% CI, 5.0%-16.9%), and 13.9% (95% CI, 8.1%-23.1%), respectively. Nonchromosomal MCA was present in 3/150 live births, corresponding to an MCA rate of 2.0% (95%CI, 0.6%-6.1%), none were reported in pregnancy losses. Compared to reference standards, birth weight (BW) tended to be lower and neonatal HC to be smaller in exposed newborns (data available for 144 and 73 of 153 live births, respectively). In nonadjusted linear regression models, each 100 mg increase of average dosage per pregnancy day was associated with a decrease in standard deviation score (SDS) of -0.28 SDS (95% CI, -0.45 to -0.10) for BW and of -0.28 SDS (95% CI, -0.56 to 0.01) for HC. Screening of 22 retrospectively reported cases did not reveal any specific pattern of MCA or other adverse outcomes. CONCLUSION: The results do not indicate an increased risk of MCA after in utero exposure to modafinil, but a tendency toward lower BW and reduced neonatal HC. However, these findings should be regarded as preliminary. Until further studies allow for a definite conclusion, modafinil should not be used during pregnancy.

8.
Cell Rep ; 42(10): 113240, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37819761

RESUMEN

The fungal pathogen Candida albicans is linked to chronic brain diseases such as Alzheimer's disease (AD), but the molecular basis of brain anti-Candida immunity remains unknown. We show that C. albicans enters the mouse brain from the blood and induces two neuroimmune sensing mechanisms involving secreted aspartic proteinases (Saps) and candidalysin. Saps disrupt tight junction proteins of the blood-brain barrier (BBB) to permit fungal brain invasion. Saps also hydrolyze amyloid precursor protein (APP) into amyloid ß (Aß)-like peptides that bind to Toll-like receptor 4 (TLR4) and promote fungal killing in vitro while candidalysin engages the integrin CD11b (Mac-1) on microglia. Recognition of Aß-like peptides and candidalysin promotes fungal clearance from the brain, and disruption of candidalysin recognition through CD11b markedly prolongs C. albicans cerebral mycosis. Thus, C. albicans is cleared from the brain through innate immune mechanisms involving Saps, Aß, candidalysin, and CD11b.


Asunto(s)
Antígeno CD11b , Microglía , Micosis , Receptor Toll-Like 4 , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/microbiología , Péptidos beta-Amiloides/metabolismo , Candida albicans/metabolismo , Proteínas Fúngicas/metabolismo , Microglía/metabolismo , Microglía/microbiología , Micosis/genética , Micosis/metabolismo , Receptor Toll-Like 4/metabolismo , Antígeno CD11b/metabolismo
9.
J Am Chem Soc ; 145(36): 19780-19789, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37649399

RESUMEN

To develop luminescent molecular materials with predictable and stimuli-responsive emission, it is necessary to correlate changes in their geometries, packing structures, and noncovalent interactions with the associated changes in their optical properties. Here, we demonstrate that high-pressure single-crystal X-ray diffraction can be combined with high-pressure UV-visible absorption and fluorescence emission spectroscopies to elucidate how subtle changes in structure influence optical outputs. A piezochromic aggregation-induced emitter, sym-heptaphenylcycloheptatriene (Ph7C7H), displays bathochromic shifts in its absorption and emission spectra at high pressure. Parallel X-ray measurements identify the pressure-induced changes in specific phenyl-phenyl interactions responsible for the piezochromism. Pairs of phenyl rings from neighboring molecules approach the geometry of a stable benzene dimer, while conformational changes alter intramolecular phenyl-phenyl interactions correlated with a relaxed excited state. This tandem crystallographic and spectroscopic analysis provides insights into how subtle structural changes relate to the photophysical properties of Ph7C7H and could be applied to a library of similar compounds to provide general structure-property relationships in fluorescent organic molecules with rotor-like geometries.

10.
Obstet Med ; 16(1): 40-47, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37124763

RESUMEN

Background: COVID-19 vaccines are protective against disease. Pregnant women benefit from vaccination as they are at higher risk of poor maternal and neonatal outcomes following infection. Methods: Following regulatory approval of two COVID-19 vaccines in the United Kingdom, a rapid national study of vaccination in pregnancy was instituted using three existing safety surveillance platforms: UKOSS, UKTIS and VIP. This preliminary report describes the data collected up to the 15th June 2021. Results: There were 971 reports of COVID-19 vaccination in the UKOSS/UKTIS (n = 493) and VIP (n = 478) monitoring systems describing 908 individual pregnancies. Pfizer-BioNTech mRNA vaccination was most common (n = 501, 55.2%), most women were vaccinated in their second or third trimester (n = 566, 62.3%), and were mainly vaccinated due to occupational infection risk (n = 577, 63.5%). Conclusion: Obstetric outcome data will be obtained by December 2021. However, women should not delay vaccination whilst awaiting further safety data to emerge.

12.
Drug Saf ; 46(5): 479-491, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36976447

RESUMEN

INTRODUCTION AND OBJECTIVE: The risks and benefits of medication use in pregnancy are typically established through post-marketing observational studies. As there is currently no standardised or systematic approach to the post-marketing assessment of medication safety in pregnancy, data generated through pregnancy pharmacovigilance (PregPV) research can be heterogenous and difficult to interpret. The aim of this article is to describe the development of a reference framework of core data elements (CDEs) for collection in primary source PregPV studies that can be used to standardise data collection procedures and, thereby, improve data harmonisation and evidence synthesis capabilities. METHODS: This CDE reference framework was developed within the Innovative Medicines Initiative (IMI) ConcePTION project by experts in pharmacovigilance, pharmacoepidemiology, medical statistics, risk-benefit communication, clinical teratology, reproductive toxicology, genetics, obstetrics, paediatrics, and child psychology. The framework was produced through a scoping review of data collection systems used by established PregPV datasets, followed by extensive discussion and debate around the value, definition, and derivation of each data item identified from these systems. RESULTS: The finalised listing of CDEs comprises 98 individual data elements, arranged into 14 tables of related fields. These data elements are openly available on the European Network of Teratology Information Services (ENTIS) website ( http://www.entis-org.eu/cde ). DISCUSSION: With this set of recommendations, we aim to standardise PregPV primary source data collection processes to improve the speed at which high-quality evidence-based statements can be provided about the safety of medication use in pregnancy.


Asunto(s)
Investigación Biomédica , Farmacovigilancia , Embarazo , Femenino , Humanos , Niño , Recolección de Datos
13.
BJPsych Bull ; 47(6): 352-356, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36700251

RESUMEN

To monitor for drug-related cardiac arrhythmias, psychiatrists regularly perform and interpret 12-lead (12L) and, increasingly often, six-lead (6L) electrocardiograms (ECGs). It is not known how training on this complex skill is updated or how well psychiatrists can interpret relevant arrhythmias on either device.We conducted an online survey and ECG interpretation test of cardiac rhythms relevant to psychiatrists.A total of 183 prescribers took part; 75% did not regularly update their ECG interpretation skills, and only 22% felt confident in interpreting ECGs. Most participants were able to recognise normal ECGs. For both 6L and 12L ECGs, the majority of participants were able to recognise abnormal ECGs, but fewer than 50% were able to correctly identify relevant arrhythmias (complete heart block and long QTc). A small number prescribed in the presence of potentially fatal arrhythmias. These findings suggest a need for mandatory ECG interpretation training to improve safe prescribing practice.

14.
J Clin Psychopharmacol ; 43(1): 12-19, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36584245

RESUMEN

PURPOSE/BACKGROUND: Trazodone is indicated for the treatment of major depressive disorder, but more frequently prescribed off-label at lower doses for insomnia in women of childbearing age. The aim of this study was to assess the risks linked to trazodone exposure during pregnancy for which limited safety data are available. METHODS/PROCEDURES: This multicenter, observational prospective cohort study compared pregnancy outcomes in women exposed to trazodone in early pregnancy against those in a reference group of women exposed to a selective serotonin reuptake inhibitors (SSRIs) between 1996 and 2021. FINDINGS/RESULTS: The sample included 221 trazodone and 869 SSRI-exposed pregnancies. Exposure to trazodone in the first trimester was not associated with a significant difference in the risk of major congenital anomalies (trazodone [1/169, 0.6%]; SSRI [19/730, 2.6%]; adjusted odds ratio, 0.2; 95% confidence interval, 0.03-1.77). The cumulative incidences of live birth were 61% and 73% in the trazodone and reference group, respectively (25% vs 18% for pregnancy loss and 14% vs 10% for pregnancy termination). Trazodone exposure was not associated with a significantly increased risk of pregnancy termination and pregnancy loss. The rate of small for gestational age infants did not differ between the groups. IMPLICATIONS/CONCLUSIONS: This study did not reveal a significant difference in the risk of major congenital anomalies after first trimester exposure to trazodone, compared with SSRI exposure. Although this study is the largest so far, these results call for confirmation through further studies.


Asunto(s)
Trastorno Depresivo Mayor , Complicaciones del Embarazo , Trazodona , Embarazo , Femenino , Humanos , Estudios de Cohortes , Trazodona/efectos adversos , Exposición Materna , Estudios Prospectivos , Complicaciones del Embarazo/tratamiento farmacológico , Complicaciones del Embarazo/epidemiología
15.
Br J Clin Pharmacol ; 89(2): 630-640, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36403130

RESUMEN

In March 2022, the Summary of Product Characteristics for the Lyrica brand of pregabalin was updated with warnings regarding malformation risks. This literature review and critical appraisal aims to explore whether these Summary of Product Characteristics updates are justified and provide clarity on the risk-benefit balance for pregabalin use in early pregnancy. A literature review was conducted in May 2022 to identify English language comparative studies of any design providing data about first trimester maternal pregabalin use and malformation risk. Five observational comparative cohort studies using data from 9 distinct datasets were located. Collectively these studies described at least 5300 unique pregabalin exposed pregnancies, with 4900 exposed in at least the first trimester. Three studies investigated overall major malformation risks, and 4 investigated specific malformation risks. The available evidence was found to be conflicting and generally of low quality, probably influenced by bias and data confounding, with no clear pattern of specific malformations observed. Findings from the largest study suggested absolute risks of major malformation of 4.8-5.6%, relative to a background risk of approximately 4%. Due to study methodology limitations, the available data were judged to only provide low quality evidence suggestive of a possible and unconfirmed small increased risk that cannot be solely attributed to foetal pregabalin exposure. This literature review and critical appraisal indicates that the Lyrica product literature updates are insufficiently substantiated and could result in confusion and misinformed clinical risk-benefit decision making.


Asunto(s)
Pregabalina , Embarazo , Femenino , Humanos , Pregabalina/efectos adversos , Primer Trimestre del Embarazo
16.
ACS Pharmacol Transl Sci ; 5(9): 735-751, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36110379

RESUMEN

Whereas treatment of allergic diseases such as asthma relies largely on the targeting of dysregulated effector pathways, the conceptually attractive alternative of preventing them by a pharmaceutical, at-source intervention has been stymied until now by uncertainties about suitable targets and the challenges facing drug design. House dust mites (HDMs) are globally significant triggers of allergy. Group 1 HDM allergens, exemplified by Der p 1, are cysteine proteases. Their degradome has a strong disease linkage that underlies their status as risk and initiator allergens acting directly and through bystander effects on other allergens. Our objective was to test whether target-selective inhibitors of group 1 HDM allergens might provide a viable route to novel therapies. Using structure-directed design to optimize a series of pyruvamides, we undertook the first examination of whether pharmaceutically developable inhibitors of group 1 allergens might offer protection against HDM exposure. Developability criteria included durable inhibition of clinically relevant signals after a single aerosolized dose of the drug. The compounds suppressed acute airway responses of rats and mice when challenged with an HDM extract representing the HDM allergome. Inhibitory effects operated through a miscellany of downstream pathways involving, among others, IL-33, thymic stromal lymphopoietin, chemokines, and dendritic cells. IL-13 and eosinophil recruitment, indices of Th2 pathway activation, were strongly attenuated. The surprisingly expansive benefits arising from a unique at-source intervention suggest a novel approach to multiple allergic diseases in which HDMs play prominent roles and encourage exploration of these pharmaceutically developable molecules in a clinical setting.

17.
J Biol Chem ; 298(10): 102419, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36037968

RESUMEN

Candida albicans (C. albicans) is a dimorphic commensal human fungal pathogen that can cause severe oropharyngeal candidiasis (oral thrush) in susceptible hosts. During invasive infection, C. albicans hyphae invade oral epithelial cells (OECs) and secrete candidalysin, a pore-forming cytolytic peptide that is required for C. albicans pathogenesis at mucosal surfaces. Candidalysin is produced in the hyphal invasion pocket and triggers cell damage responses in OECs. Candidalysin also activates multiple MAPK-based signaling events that collectively drive the production of downstream inflammatory mediators that coordinate downstream innate and adaptive immune responses. The activities of candidalysin are dependent on signaling through the epidermal growth factor receptor (EGFR). Here, we interrogated known EGFR-MAPK signaling intermediates for their roles mediating the OEC response to C. albicans infection. Using RNA silencing and pharmacological inhibition, we identified five key adaptors, including growth factor receptor-bound protein 2 (Grb2), Grb2-associated binding protein 1 (Gab1), Src homology and collagen (Shc), SH2-containing protein tyrosine phosphatase-2 (Shp2), and casitas B-lineage lymphoma (c-Cbl). We determined that all of these signaling effectors were inducibly phosphorylated in response to C. albicans. These phosphorylation events occurred in a candidalysin-dependent manner and additionally required EGFR phosphorylation, matrix metalloproteinases (MMPs), and cellular calcium flux to activate a complete OEC response to fungal infection. Of these, Gab1, Grb2, and Shp2 were the dominant drivers of ERK1/2 activation and the subsequent production of downstream innate-acting cytokines. Together, these results identify the key adaptor proteins that drive the EGFR signaling mechanisms that underlie oral epithelial responses to C. albicans.


Asunto(s)
Candida albicans , Candidiasis Bucal , Receptores ErbB , Proteínas Fúngicas , Mucosa Bucal , Humanos , Candida albicans/metabolismo , Candida albicans/patogenicidad , Citocinas/metabolismo , Receptores ErbB/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Adaptadoras de la Señalización Shc/metabolismo , Candidiasis Bucal/metabolismo , Candidiasis Bucal/microbiología , Mucosa Bucal/metabolismo , Mucosa Bucal/microbiología , Células Epiteliales/metabolismo , Células Epiteliales/microbiología
18.
Methods Mol Biol ; 2542: 163-176, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36008664

RESUMEN

In 2016, the first peptide toxin in any human fungal pathogen was identified. It was discovered in Candida albicans and was named candidalysin. Candidalysin is an amphipathic cationic peptide that damages cell membranes. Like most lytic peptides, candidalysin shows alpha-helical secondary structure. As the helicity and the membrane lytic activity of candidalysin are key factors for pathogenicity, here we describe in vitro approaches to monitor both its membrane-lytic function and the secondary structure. First, membrane permeabilization activity of candidalysin is measured in real time by direct electrical recording. Second, the secondary structure and helicity of candidalysin are determined by circular dichroism spectroscopy. These biophysical methods provide a means to characterize the activity and physical properties of candidalysin in vitro and will be useful in determining the structural and functional features of candidalysin and other similar cationic membrane-active peptides.


Asunto(s)
Proteínas Fúngicas , Micotoxinas , Candida albicans/metabolismo , Dicroismo Circular , Proteínas Fúngicas/metabolismo , Humanos , Micotoxinas/metabolismo , Péptidos/metabolismo , Virulencia
19.
J Med Case Rep ; 16(1): 221, 2022 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-35659714

RESUMEN

BACKGROUND: Prostate cancer may rarely metastasize to the colon and colonic lymph nodes, and local treatment of oligometastatic deposits may improve oncological outcomes. Immunohistochemical stains are used to determine the most likely source of metastatic deposits when they are seen within surgical specimens. The aim of this case report is to illustrate how such techniques were used to identify unexpected prostatic metastases within the pericolic fat of a sigmoid colon resection specimen following elective curative surgery for colorectal cancer. To our knowledge, this is the first report of complete excision of oligometastatic deposits of prostate cancer found incidentally within the specimen of another cancer. CASE REPORT: An 89-year-old Caucasian man underwent sigmoid colectomy for an obstructing colorectal cancer in the sigmoid colon with some mesenteric lymphadenopathy. He had previously received radical radiotherapy for prostate cancer 10 years earlier. When the specimen was examined by the histopathologist, it was noted that the pericolic fat adjacent to the colorectal adenocarcinoma contained some metastatic deposits. Positive immunohistochemical staining for prostate-specific antigen and prostate-specific acid phosphatase with negative staining for CDX2 and CK20 revealed these to be prostatic metastases rather than colonic. Since these were completely excised, and there were no other metastases, this represented a serendipitous, curative excision of oligometastatic deposits of an additional cancer to the one that was being treated. CONCLUSIONS: This case illustrates how immunohistochemical staining may be used to distinguish the source of metastatic deposits based on the likelihood of primary tumor from a careful and thorough patient history.


Asunto(s)
Adenocarcinoma , Carcinoma , Neoplasias del Colon , Neoplasias de la Próstata , Adenocarcinoma/patología , Anciano de 80 o más Años , Carcinoma/cirugía , Colectomía , Colon Sigmoide/patología , Colon Sigmoide/cirugía , Neoplasias del Colon/cirugía , Humanos , Masculino , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía
20.
Behav Brain Res ; 432: 113978, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-35753530

RESUMEN

Although rodents have represented the most intensely studied animals in neurobiological investigations for more than a century, few studies have systematically compared neural and endocrine differences between wild rodents in their natural habitats and laboratory strains raised in traditional laboratory environments. In the current study, male and female Rattus norvegicus rats were trapped in an urban setting and compared to weight-and sex-matched conspecifics living in standard laboratory housing conditions. Brains were extracted for neural assessments and fecal boli were collected for endocrine [corticosterone and dehydroepiandrosterone (DHEA)] assays. Additionally, given their role in immune and stress functions, spleen and adrenal weights were recorded. A separate set of wild rats was trapped at a dairy farm and held in captivity for one month prior to assessments; in these animals, brains were processed but no hormone data were available. The results indicated that wild-trapped rats exhibited 31% heavier brains, including higher densities of cerebellar neurons and glial cells in the bed nucleus of the stria terminalis. The wild rats also had approximately 300% greater spleen and adrenal weights, and more than a six-fold increase in corticosterone levels than observed in laboratory rats. Further research on neurobiological variables in wild vs. lab animals will inform the extensive neurobiological knowledge base derived from laboratory investigations using selectively bred rodents in laboratory environments, knowledge that will enhance the translational value of preclinical laboratory rodent studies.


Asunto(s)
Corticosterona , Neuroglía , Animales , Encéfalo , Femenino , Masculino , Ratas
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