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1.
Cureus ; 16(9): e69185, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39282484

RESUMEN

INTRODUCTION: In Romania, the latest official report indicates that more than half of the births (80,890 cases, representing 52.88% of the total) are performed by cesarean, a rate significantly higher than the World Health Organization (WHO) recommendation of 15-20%. This study aims to identify the predictors associated with women's decisions to opt for cesarean in Romania. MATERIALS AND METHODS:  An analytical cross-sectional observational study was conducted in the general population of Romania. The study was carried out over the course of 2023, with a total duration of four months. During this period, researchers targeted pregnant women from various regions of the country, regardless of their place of residence, age, or education level. The primary data collection tool was a self-administered online questionnaire, distributed via Google Forms, an accessible and efficient platform that allows for automatic response collection. The questionnaire was distributed online, particularly on social media platforms frequented by pregnant women, such as Facebook, Instagram, and TikTok. RESULTS: A total of 1,301 participants were validated. Socio-demographic and clinical factors significantly influence women's decisions to give birth by cesarean. Among these participants, 435 expressed a preference for cesarean delivery. Key predictors include fear of pain and concern for the child's health. Fear of pain at birth is the first predictor in Romanian women to choose cesarean (OR=2.09; 95% CI: 1.62-2.68). Concerns about the child's health do not increase the likelihood of opting for a cesarean. CONCLUSION:  By utilizing valuable resources such as midwives and implementing strategies like birth plans, significant contributions can be made toward reducing the cesarean rate and improving the childbirth experience for women worldwide.

3.
Life (Basel) ; 14(9)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39337841

RESUMEN

OBJECTIVES: To assess the predictive value of serum trypsin and trypsinogen activation peptide (TAP) for the severity of AP through a single center cohort study as well as a systematic review of the current literature. METHODS: A literature search was conducted using Medline (PubMed), EMBASE and the Cochrane Central Register. A total of 142 patients with acute pancreatitis (AP) were included in the cohort study and parameters of the revised Atlanta criteria of 2012 and the APACHE II were assessed. RESULTS: The review showed promising results for the predictive value of serum trypsinogen-2 but conflicting results for serum TAP and trypsin. In the cohort study, patients were observed for 4 days after diagnosis of AP; 9 patients had severe AP, 35 patients had moderate AP and 81 patients had mild AP. The ratio of the geometric mean of severe vs. mild AP for trypsin was 0.72 (95% CI: 0.51-1.00), p = 0.053 and, for TAP, 0.74 (95% CI: 0.54-1.01), p = 0.055, respectively. CONCLUSIONS: The cohort study showed an inverse correlation of serum levels of TAP and trypsin with severity of AP. Serum TAP and trypsin have an inferior predictive value of severity of AP compared to the clinical APACHE II score.

4.
J Am Chem Soc ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39332019

RESUMEN

Optical-spin interfaces that enable the photoinitialization, coherent microwave manipulation, and optical read-out of ground state spins have been studied extensively in solid-state defects such as diamond nitrogen vacancy (NV) centers and are promising for quantum information science applications. Molecular quantum bits (qubits) offer many advantages over solid-state spin centers through synthetic control of their optical and spin properties and their scalability into well-defined multiqubit arrays. In this work, we report an optical-spin interface in an organic molecular qubit consisting of two luminescent tris(2,4,6-trichlorophenyl)methyl (TTM) radicals connected via the meta-positions of a phenyl linker. The triplet ground state of this system can be photoinitialized in its |T0⟩ state by shelving triplet populations as singlets through spin-selective excited-state intersystem crossing with 80% selectivity from |T+⟩ and |T-⟩. The fluorescence intensity in the triplet manifold is determined by the ground-state polarization, and we show successful optical read-out of the ground-state spin following microwave manipulations by fluorescence-detected magnetic resonance spectroscopy. At 85 K, the lifetime of the polarized ground state is 45 ± 3 µs, and the ground state phase memory time is Tm = 5.9 ± 0.1 µs, which increases to 26.8 ± 1.6 µs at 5 K. These results show that luminescent diradicals with triplet ground states can serve as optically addressable molecular qubits with long spin coherence times, which marks an important step toward the rational design of spin-optical interfaces in organic materials.

5.
Biofactors ; 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39345206

RESUMEN

The thyroid hormone (TH) status is routinely assessed by thyrotropin (TSH) and thyroxine (T4). Both biomarkers are mainly regulated by TH receptor beta, whereas many peripheral organs employ the alpha receptor. Serum cluster of differentiation 5-like molecule (CD5L) is a liver-derived protein under control of both TH receptor isoforms. However, clinical data on its relation to TH status are sparse. An additional biomarker of TH status is needed in particular during pregnancy, where the routine biomarkers become dynamically disturbed. This study aimed to determine possible covariates regulating serum CD5L and to test its potential suitability as additional TH biomarker during pregnancy. A sandwich ELISA for serum CD5L was established using newly raised antibodies. Circadian effects and the impact of liver disease on serum CD5L concentrations were assessed. Serum samples from pregnant women with well-characterized TH and trace element status were analyzed, and CD5L concentrations were correlated with other indicators of TH status including TSH, fT4, fT3, copper, and selenium concentrations. The new quantitative assay for CD5L showed high accuracy. Serum CD5L was stable in dilution and refreezing experiments and did not show strong circadian variance or dependency on liver disease. In serum of pregnant women, CD5L correlated positively to fT3, but not to fT4 or TSH. Significant positive correlations of CD5L were observed with serum levels of the TH-responsive trace elements selenium and copper. The data support the potential suitability of serum CD5L as an additional marker of TH status, with potential value for pregnancy and thyroid disease.

6.
Am J Sports Med ; : 3635465241273947, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324486

RESUMEN

BACKGROUND: Fresh osteochondral allograft (OCA) transplantation is an effective technique for the treatment of focal chondral and osteochondral defects in the knee. Coronal-plane malalignment leads to increased contact forces within a compartment and subsequently the cartilage repair site and may lead to higher failure rates. However, the magnitude of the effect of coronal-plane malalignment on graft survivorship and clinical outcomes has not been well characterized. PURPOSE: To evaluate how varus malalignment affects graft survival and patient-reported outcomes after isolated OCA transplantation of the medial femoral condyle (MFC). STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 70 patients (74 knees) who underwent primary OCA transplantation of the MFC between 2005 and 2019 were identified from a prospectively collected single-surgeon cartilage registry with a minimum 2-year follow-up. Coronal-plane alignment was evaluated utilizing standing hip-to-ankle radiographs. OCA failure, defined as removal of the graft or conversion to arthroplasty, and reoperations were recorded. Patient-reported outcomes were obtained preoperatively and postoperatively using the International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, modified Merle d'Aubigné-Postel score, and overall patient satisfaction score. RESULTS: The mean mechanical tibiofemoral angle for patients with varus alignment was 3.9° of varus (range, 1.1° to 8.9°) and for patients with nonvarus alignment it was 0.02° of valgus (range, 3.6° varus to 4.6° valgus). Graft survivorship was 95.3% in the varus group and 95.8% in the nonvarus group (P = .918) at 5 years postoperatively. Reoperations after OCA transplantation occurred in 14.0% of the varus group and 22.6% of the nonvarus group (P = .336). The mean International Knee Documentation Committee total score improved from 45.2 preoperatively to 74.8 at latest follow-up in the varus group and from 40.5 preoperatively to 72.3 at latest follow-up in the nonvarus group. Patient satisfaction was >85%. CONCLUSION: Patients undergoing isolated OCA transplantation of the MFC had high rates (>90%) of graft survivorship and significant improvements in pain and function. Patients with mild preexisting varus malalignment were found to have no difference in the failure rate or clinical outcomes compared with patients with nonvarus alignment.

7.
J Couns Psychol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250277

RESUMEN

Transgender and nonbinary (TNB) people experience elevated rates of posttraumatic stress (PTS) due to transphobic violence, discrimination, microaggressions, and minority stress. Nonbinary people in particular experience unique chronic minority stressors (e.g., misgendering, interpersonal invalidation) because of the assumption that gender is inherently binary. Such examples of oppression against TNB people could contribute to complex PTS (c-PTS) symptoms, which arise due to exposure to chronic, cumulative, and interpersonal trauma. This study aimed to examine how misgendering and invalidation may be associated with PTS and c-PTS symptoms among nonbinary people and whether this association is moderated by pride and community connectedness. Cross-sectional data from 610 nonbinary people living in the United States and Canada were analyzed using hierarchical linear regressions. Misgendering and invalidation had significant positive associations with PTS and c-PTS symptoms. However, pride and community connectedness were not significant moderators of these associations. Findings from this study contribute to the conceptualizations of traumatic stress among nonbinary people and provide considerations for more affirming trauma-informed care. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

8.
J Neurosurg Pediatr ; : 1-14, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39303299

RESUMEN

OBJECTIVE: Intraoperative magnetic resonance imaging (iMRI) use is becoming increasingly widespread in neurosurgical practice, and most of the data reporting its use are in adult populations. There is less evidence on the use of iMRI in pediatric neurosurgery. The aim of this paper was to synthesize the available literature into a systematic review and meta-analysis to evaluate the evidence for iMRI in pediatric neurosurgery, with a particular focus on neuro-oncology and epilepsy surgery. METHODS: This review was registered on PROSPERO and conducted according to PRISMA guidelines. A comprehensive search strategy of Medline via Ovid and Embase was conducted with predetermined key terms. Studies in English reporting the outcomes of patients < 21 years of age who underwent neuro-oncological or epilepsy surgery with the use of iMRI were included in the study. The types of studies eligible for inclusion were observational case-control and cohort studies, randomized clinical trials, cross-sectional studies, editorials, case series, and commentaries. Articles were de-duplicated and abstracts independently screened for inclusion by two reviewers. Full texts were screened, and data on demographic characteristics, etiology, outcome (extent of resection for neuro-oncology and Engel class for epilepsy), and technical iMRI data were extracted. RESULTS: Thirty-five articles were included in the review, 25 of which were observational cohort studies. Four articles were suitable for meta-analysis. In total, 1217 patients underwent iMRI-guided neuro-oncology surgery in 26 studies, most commonly for gliomas (n = 443). A total of 148 patients underwent iMRI-guided epilepsy surgery in 9 studies, with focal cortical dysplasia being the most common diagnosis (n = 95). The mean ± SD operating time was 357 ± 94 minutes (12 studies), with a mean of 1.32 scans per patient. There was a mean re-entry rate into the operative field of 42% (across 20 studies). Complications were noted in 21% of epilepsy surgery patients and 11% of neuro-oncology surgery patients. Meta-analysis of 4 eligible studies revealed that iMRI was more likely to lead to better Engel outcomes in terms of seizure freedom (OR 3.84, 95% CI 1.38-10.68, p = 0.69) and complete tumor resection (OR 3.19, 95% CI 0.28-36.92, p = 0.06). CONCLUSIONS: iMRI appears to be a useful adjunct in optimizing resective pediatric epilepsy and neuro-oncology surgery, with a low complication rate.

9.
bioRxiv ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39253514

RESUMEN

The interplay between transcription factors and chromatin accessibility regulates cell type diversification during vertebrate embryogenesis. To systematically decipher the gene regulatory logic guiding this process, we generated a single-cell multi-omics atlas of RNA expression and chromatin accessibility during early zebrafish embryogenesis. We developed a deep learning model to predict chromatin accessibility based on DNA sequence and found that a small number of transcription factors underlie cell-type-specific chromatin landscapes. While Nanog is well-established in promoting pluripotency, we discovered a new function in priming the enhancer accessibility of mesendodermal genes. In addition to the classical stepwise mode of differentiation, we describe instant differentiation, where pluripotent cells skip intermediate fate transitions and terminally differentiate. Reconstruction of gene regulatory interactions reveals that this process is driven by a shallow network in which maternally deposited regulators activate a small set of transcription factors that co-regulate hundreds of differentiation genes. Notably, misexpression of these transcription factors in pluripotent cells is sufficient to ectopically activate their targets. This study provides a rich resource for analyzing embryonic gene regulation and reveals the regulatory logic of instant differentiation.

10.
Clin Transl Radiat Oncol ; 48: 100838, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39224662

RESUMEN

Aims: Multidisciplinary tumor boards (MDTs) are an integral part of ensuring high-quality, evidence-based and personalized cancer care. In this study, we aimed to evaluate the adherence to and implementation of MDT recommendations in patients with oligometastatic disease (OMD). Methods: We screened all oncologic positron emission tomography (PET) scans conducted at a single comprehensive cancer center in 2020. Patients were included if they had evidence of imaging-based OMD from a solid organ malignancy on the index scans, had their OMD case discussed at an MDT, and were treated and followed up at the same center. A switch away from the MDT-recommended treatment modalities was classified as a major deviation; non-MDT-mandated adjustments to a recommended treatment modality were coded as minor deviation. Clinical data was obtained via chart review; statistical calculations were computed using the R software. Results: After review of PET and/or concurrent brain scans, 787 cases of OMD were identified. Thereof, 347 (44.1 %) cases were discussed at MDT, of which 331 (42.1 %) were therapeutically managed and subsequently followed. The three most commonly recommended therapies were systemic therapy (35.6 %), multimodality treatment including definitive local therapy (17.8 %), and radiotherapy (13.9 %). A major deviation was recorded in 16.3 % of cases (most commonly: none of the MDT-recommended treatment modalities were performed: 19 (35.2 %); not all MDT-planned treatment modalities were performed: 12 (22.2 %); and additional treatment modality was performed: 11 (20.3 %). A minor deviation was found in 1.5 % of cases. On multivariable regression, number of distant metastases (n > 1) was associated with a major deviation (OR: 1.85; 95 % CI, 1.0-3.52). Major deviations were associated with a significantly worse OS (p = 0.0034). Conclusions: Adherence to and implementation of MDT recommendations in OMD patients was generally high (83.7%). Major deviations might be further reduced by more careful and elaborate discussions of OMD patient characteristics s and patient preferences.

11.
BJA Educ ; 24(8): 288-295, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39099752
12.
J Am Chem Soc ; 146(31): 21476-21489, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39042706

RESUMEN

The dynamics of electron and spin transfer in the radical cation and photogenerated triplet states of a tetramethylbiphenyl-linked zinc-porphyrin dimer were investigated, so as to test the relevant parameters for the design of a single-molecule spin valve and the creation of a novel platform for the photogeneration of high-multiplicity spin states. We used a combination of multiple techniques, including variable-temperature continuous wave EPR, pulsed proton electron-nuclear double resonance (ENDOR), transient EPR, and optical spectroscopy. The conclusions are further supported by density functional theory (DFT) calculations and comparison to reference compounds. The low-temperature cw-EPR and room-temperature near-IR spectra of the dimer monocation demonstrate that the radical cation is spatially localized on one side of the dimer at any point in time, not coherently delocalized over both porphyrin units. The EPR spectra at 298 K reveal rapid hopping of the radical spin density between both sites of the dimer via reversible intramolecular electron transfer. The hyperfine interactions are modulated by electron transfer and can be quantified using ENDOR spectroscopy. This allowed simulation of the variable-temperature cw-EPR spectra with a two-site exchange model and provided information on the temperature-dependence of the electron transfer rate. The electron transfer rates range from about 10.0 MHz at 200 K to about 53.9 MHz at 298 K. The activation enthalpies Δ‡H of the electron transfer were determined as Δ‡H = 9.55 kJ mol-1 and Δ‡H = 5.67 kJ mol-1 in a 1:1:1 solvent mixture of CD2Cl2/toluene-d8/THF-d8 and in 2-methyltetrahydrofuran, respectively, consistent with a Robin-Day class II mixed valence compound. These results indicate that the interporphyrin electronic coupling in a tetramethylbiphenyl-linked porphyrin dimer is suitable for the backbone of a single-molecule spin valve. Investigation of the spin density distribution of the photogenerated triplet state of the Zn-porphyrin dimer reveals localization of the triplet spin density on a nanosecond time scale on one-half of the dimer at 20 K in 2-methyltetrahydrofuran and at 250 K in a polyvinylcarbazole film. This establishes the porphyrin dimer as a molecular platform for the formation of a localized, photogenerated triplet state on one porphyrin unit that is coupled to a second redox-active, ground-state porphyrin unit, which can be explored for the formation of high-multiplicity spin states.

13.
J Extracell Vesicles ; 13(7): e12476, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38978287

RESUMEN

The current study analyzed the intersecting biophysical, biochemical, and functional properties of extracellular particles (EPs) with the human immunodeficiency virus type-1 (HIV-1) beyond the currently accepted size range for HIV-1. We isolated five fractions (Frac-A through Frac-E) from HIV-infected cells by sequential differential ultracentrifugation (DUC). All fractions showed a heterogeneous size distribution with median particle sizes greater than 100 nm for Frac-A through Frac-D but not for Frac-E, which contained small EPs with an average size well below 50 nm. Synchronized and released cultures contained large infectious EPs in Frac-A, with markers of amphisomes and viral components. Additionally, Frac-E uniquely contained EPs positive for CD63, HSP70, and HIV-1 proteins. Despite its small average size, Frac-E contained membrane-protected viral integrase, detectable only after SDS treatment, indicating that it is enclosed in vesicles. Single particle analysis with dSTORM further supported these findings as CD63, HIV-1 integrase, and the viral surface envelope (Env) glycoprotein (gp) colocalized on the same Frac-E particles. Surprisingly, Frac-E EPs were infectious, and infectivity was significantly reduced by immunodepleting Frac-E with anti-CD63, indicating the presence of this protein on the surface of infectious small EPs in Frac-E. To our knowledge, this is the first time that extracellular vesicle (EV) isolation methods have identified infectious small HIV-1 particles (smHIV-1) that are under 50 nm. Collectively, our data indicate that the crossroads between EPs and HIV-1 potentially extend beyond the currently accepted biophysical properties of HIV-1, which may have further implications for viral pathogenesis.


Asunto(s)
Vesículas Extracelulares , Infecciones por VIH , VIH-1 , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/virología , Infecciones por VIH/virología , Infecciones por VIH/metabolismo , Virión/metabolismo , Ultracentrifugación/métodos , Linfocitos T/virología , Linfocitos T/metabolismo , Tetraspanina 30/metabolismo , Tamaño de la Partícula
14.
Cardiooncology ; 10(1): 43, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014463

RESUMEN

AIMS: Cancer therapy-related cardiac dysfunction (CTRCD) is a dreaded complication of anthracycline therapy. CTRCD most frequently appears in patients with cardiovascular risk factors (CVR) or known cardiovascular disease. However, limited data exist on incidence and course of anthracycline-induced CTRCD in patients without preexisting risk factors. We therefore aimed to longitudinally investigate a cohort of young women on anthracycline treatment due to breast cancer without cardiovascular risk factors or known cardiovascular disease (NCT03940625). METHODS AND RESULTS: We enrolled 59 women with primary breast cancer and scheduled anthracycline-based therapy, but without CVR or preexisting cardiovascular disease. We conducted a longitudinal assessment before, immediately and 12 months after cancer therapy with general laboratory, electrocardiograms, echocardiography and cardiovascular magnetic resonance (CMR), including myocardial relaxometry with T1, T2 and extracellular volume mapping. Every single patient experienced a drop in CMR-measured left ventricular ejection fraction (LVEF) of 6 ± 3% immediately after cancer therapy. According to the novel definition 32 patients (54.2%) developed CTRCD after 12 months defined by reduction in LVEF, global longitudinal strain (GLS) and/or biomarkers elevation, two of them were symptomatic. Global myocardial T2 relaxation times as well as myocardial mass increased coincidently with a decline in wall-thickening. While T2 values and myocardial mass normalized after 12 months, LVEF and GLS remained impaired. CONCLUSION: In every single patient anthracyclines induce a decline of myocardial contractility, even among patients without pre-existing risk factors for CTRCD. Our data suggest to thoroughly evaluate whether this may lead to an increased risk of future cardiovascular events.

15.
JCO Precis Oncol ; 8: e2400106, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39013133

RESUMEN

PURPOSE: The autosomal dominant cancer predisposition disorders hereditary breast and ovarian cancer (HBOC) and Lynch syndrome (LS) are genetic conditions for which early identification and intervention have a positive effect on the individual and public health. The goals of this study were to determine whether germline genetic screening using exome sequencing could be used to efficiently identify carriers of HBOC and LS. METHODS: Participants were recruited from three geographically and racially diverse sites in the United States (Rochester, MN; Phoenix, AZ; Jacksonville, FL). Participants underwent Exome+ sequencing (Helix Inc, San Mateo, CA) and return of results for specific genetic findings: HBOC (BRCA1 and BRCA1) and LS (MLH1, MSH2, MSH6, PMS2, and EPCAM). Chart review was performed to collect demographics and personal and family cancer history. RESULTS: To date, 44,306 participants have enrolled in Tapestry. Annotation and interpretation of all variants in genes for HBOC and LS resulted in the identification of 550 carriers (prevalence, 1.24%), which included 387 with HBOC (27.2% BRCA1, 42.8% BRCA2) and 163 with LS (12.3% MSH6, 8.8% PMS2, 4.5% MLH1, 3.8% MSH2, and 0.2% EPCAM). More than half of these participants (52.1%) were newly diagnosed carriers with HBOC and LS. In all, 39.2% of HBOC/LS carriers did not satisfy National Comprehensive Cancer Network (NCCN) criteria for genetic evaluation. NCCN criteria were less commonly met in underrepresented minority populations versus self-reported White race (51.5% v 37.5%, P = .028). CONCLUSION: Our results emphasize the need for wider utilization of germline genetic sequencing for enhanced screening and detection of individuals who have LS and HBOC cancer predisposition syndromes.


Asunto(s)
Predisposición Genética a la Enfermedad , Humanos , Femenino , Persona de Mediana Edad , Adulto , Masculino , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Secuenciación del Exoma , Guías de Práctica Clínica como Asunto , Anciano , Pruebas Genéticas/métodos , Adulto Joven , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Síndrome de Cáncer de Mama y Ovario Hereditario/diagnóstico , Heterocigoto
16.
Br J Haematol ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973132

RESUMEN

Management of immune thrombocytopenia (ITP) beyond initial glucocorticoid therapy is challenging. In this retrospective single-centre cohort study, we compared all ITP patients relapsed or non-responsive to glucocorticoid therapy treated with either continuous TPO-RAs (n = 35) or rituximab induction (n = 20) between 2015 and 2022. While both groups showed high initial complete response rates (CR, 68.6 vs. 80.0%, ns), the overall rate of progression to the next therapy was higher after time-limited rituximab (75.0 vs. 42.9%), resulting in a lower relapse-free survival (median 16.6 vs. 25.8 months, log-rank; p < 0.05). We conclude that both treatments show similar initial efficacy and their ideal duration of therapy warrants further investigation.

17.
Artículo en Inglés | MEDLINE | ID: mdl-39042016

RESUMEN

The pulmonary epithelial glycocalyx is rich in glycosaminoglycans such as hyaluronan and heparan sulfate. Despite their presence, the importance of these glycosaminoglycans in bacterial lung infections remains elusive. To address this, we intranasally inoculated mice with Streptococcus pneumoniae in the presence or absence of enzymes targeting pulmonary hyaluronan and heparan sulfate, followed by characterization of subsequent disease pathology, pulmonary inflammation, and lung barrier dysfunction. Enzymatic degradation of hyaluronan and heparan sulfate exacerbated pneumonia in mice, as evidenced by increased disease scores and alveolar neutrophil recruitment. However, targeting epithelial hyaluronan in combination with Streptococcus pneumoniae infection further exacerbated systemic disease, indicated by elevated splenic bacterial load and plasma levels of pro-inflammatory cytokines. In contrast, enzymatic cleavage of heparan sulfate resulted in increased bronchoalveolar bacterial burden, lung damage and pulmonary inflammation in mice infected with Streptococcus pneumoniae. Accordingly, heparinase-treated mice also exhibited disrupted lung barrier integrity as evidenced by higher alveolar edema scores and vascular protein leakage into the airways. This finding was corroborated in a human alveolus-on-a-chip platform, confirming that heparinase treatment also disrupts the human lung barrier during Streptococcus pneumoniae infection. Notably, enzymatic pre-treatment with either hyaluronidase or heparinase also rendered human epithelial cells more sensitive to pneumococcal-induced barrier disruption, as determined by transepithelial electrical resistance measurements, consistent with our findings in murine pneumonia. Taken together, these findings demonstrate the importance of intact hyaluronan and heparan sulfate in limiting pneumococci-induced damage, pulmonary inflammation, and epithelial barrier function and integrity. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

18.
Nat Commun ; 15(1): 5745, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987239

RESUMEN

Complications of diabetes are often attributed to glucose and reactive dicarbonyl metabolites derived from glycolysis or gluconeogenesis, such as methylglyoxal. However, in the CNS, neurons and endothelial cells use lactate as energy source in addition to glucose, which does not lead to the formation of methylglyoxal and has previously been considered a safer route of energy consumption than glycolysis. Nevertheless, neurons and endothelial cells are hotspots for the cellular pathology underlying neurological complications in diabetes, suggesting a cause that is distinct from other diabetes complications and independent of methylglyoxal. Here, we show that in clinical and experimental diabetes plasma concentrations of dimethylglyoxal are increased. In a mouse model of diabetes, ilvb acetolactate-synthase-like (ILVBL, HACL2) is the enzyme involved in formation of increased amounts of dimethylglyoxal from lactate-derived pyruvate. Dimethylglyoxal reacts with lysine residues, forms Nε-3-hydroxy-2-butanonelysine (HBL) as an adduct, induces oxidative stress more strongly than other dicarbonyls, causes blood-brain barrier disruption, and can mimic mild cognitive impairment in experimental diabetes. These data suggest dimethylglyoxal formation as a pathway leading to neurological complications in diabetes that is distinct from other complications. Importantly, dimethylglyoxal formation can be reduced using genetic, pharmacological and dietary interventions, offering new strategies for preventing CNS dysfunction in diabetes.


Asunto(s)
Neuropatías Diabéticas , Glioxal , Ácido Pirúvico , Complicaciones de la Diabetes/metabolismo , Complicaciones de la Diabetes/patología , Animales , Ratones , Glioxal/análogos & derivados , Neuropatías Diabéticas/metabolismo , Neuropatías Diabéticas/patología , Glucosa/metabolismo , Ácido Pirúvico/metabolismo , Acetolactato Sintasa/metabolismo , Encéfalo/metabolismo , Liasas de Carbono-Carbono/metabolismo , Humanos , Ratones Endogámicos C57BL
19.
Mol Syst Biol ; 20(9): 1006-1024, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39026103

RESUMEN

Somatic hypermutation in cancer has gained momentum with the increased use of tumour mutation burden as a biomarker for immune checkpoint inhibitors. Spontaneous deamination of 5-methylcytosine to thymine at CpG dinucleotides is one of the most ubiquitous endogenous mutational processes in normal and cancer cells. Here, we performed a systematic investigation of somatic CpG hypermutation at a pan-cancer level. We studied 30,191 cancer patients and 103 cancer types and developed an algorithm to identify somatic CpG hypermutation. Across cancer types, we observed the highest prevalence in paediatric leukaemia (3.5%), paediatric high-grade glioma (1.7%), and colorectal cancer (1%). We discovered germline variants and somatic mutations in the mismatch repair complex MutSα (MSH2-MSH6) as genetic drivers of somatic CpG hypermutation in cancer, which frequently converged on CpG sites and TP53 driver mutations. We further observe an association between somatic CpG hypermutation and response to immune checkpoint inhibitors. Overall, our study identified novel cancer types that display somatic CpG hypermutation, strong association with MutSα-deficiency, and potential utility in cancer immunotherapy.


Asunto(s)
Islas de CpG , Reparación de la Incompatibilidad de ADN , Mutación , Neoplasias , Humanos , Reparación de la Incompatibilidad de ADN/genética , Neoplasias/genética , Neoplasias/inmunología , Islas de CpG/genética , Proteína 2 Homóloga a MutS/genética , Proteína 2 Homóloga a MutS/metabolismo , Proteínas de Unión al ADN/genética , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Proteína p53 Supresora de Tumor/genética
20.
J Biol Chem ; 300(8): 107573, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39009340

RESUMEN

Galectins (Gals), a family of multifunctional glycan-binding proteins, have been traditionally defined as ß-galactoside binding lectins. However, certain members of this family have shown selective affinity toward specific glycan structures including human milk oligosaccharides (HMOs) and blood group antigens. In this work, we explored the affinity of human galectins (particularly Gal-1, -3, -4, -7, and -12) toward a panel of oligosaccharides including HMOs and blood group antigens using a complementary approach based on both experimental and computational techniques. While prototype Gal-1 and Gal-7 exhibited differential affinity for type I versus type II Lac/LacNAc residues and recognized fucosylated neutral glycans, chimera-type Gal-3 showed high binding affinity toward poly-LacNAc structures including LNnH and LNnO. Notably, the tandem-repeat human Gal-12 showed preferential recognition of 3-fucosylated glycans, a unique feature among members of the galectin family. Finally, Gal-4 presented a distinctive glycan-binding activity characterized by preferential recognition of specific blood group antigens, also validated by saturation transfer difference nuclear magnetic resonance experiments. Particularly, we identified oligosaccharide blood group A antigen tetraose 6 (BGA6) as a biologically relevant Gal-4 ligand, which specifically inhibited interleukin-6 secretion induced by this lectin on human peripheral blood mononuclear cells. These findings highlight unique determinants underlying specific recognition of HMOs and blood group antigens by human galectins, emphasizing the biological relevance of Gal-4-BGA6 interactions, with critical implications in the development and regulation of inflammatory responses.


Asunto(s)
Antígenos de Grupos Sanguíneos , Galectina 4 , Galectinas , Leche Humana , Oligosacáridos , Humanos , Leche Humana/metabolismo , Leche Humana/química , Oligosacáridos/metabolismo , Oligosacáridos/química , Antígenos de Grupos Sanguíneos/metabolismo , Antígenos de Grupos Sanguíneos/química , Galectinas/metabolismo , Galectinas/química , Ligandos , Galectina 4/metabolismo , Galectina 4/química , Unión Proteica , Interleucina-6/metabolismo
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