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1.
bioRxiv ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38712254

RESUMO

Splicing factor mutations are common in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), but how they alter cellular functions is unclear. We show that the pathogenic SRSF2P95H/+ mutation disrupts the splicing of mitochondrial mRNAs, impairs mitochondrial complex I function, and robustly increases mitophagy. We also identified a mitochondrial surveillance mechanism by which mitochondrial dysfunction modifies splicing of the mitophagy activator PINK1 to remove a poison intron, increasing the stability and abundance of PINK1 mRNA and protein. SRSF2P95H-induced mitochondrial dysfunction increased PINK1 expression through this mechanism, which is essential for survival of SRSF2P95H/+ cells. Inhibition of splicing with a glycogen synthase kinase 3 inhibitor promoted retention of the poison intron, impairing mitophagy and activating apoptosis in SRSF2P95H/+ cells. These data reveal a homeostatic mechanism for sensing mitochondrial stress through PINK1 splicing and identify increased mitophagy as a disease marker and a therapeutic vulnerability in SRSF2P95H mutant MDS and AML.

2.
J Clin Invest ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713535

RESUMO

Splicing factor mutations are common in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), but how they alter cellular functions is unclear. We show that the pathogenic SRSF2P95H/+ mutation disrupts the splicing of mitochondrial mRNAs, impairs mitochondrial complex I function, and robustly increases mitophagy. We also identified a mitochondrial surveillance mechanism by which mitochondrial dysfunction modifies splicing of the mitophagy activator PINK1 to remove a poison intron, increasing the stability and abundance of PINK1 mRNA and protein. SRSF2P95H-induced mitochondrial dysfunction increased PINK1 expression through this mechanism, which is essential for survival of SRSF2P95H/+ cells. Inhibition of splicing with a glycogen synthase kinase 3 inhibitor promoted retention of the poison intron, impairing mitophagy and activating apoptosis in SRSF2P95H/+ cells. These data reveal a homeostatic mechanism for sensing mitochondrial stress through PINK1 splicing and identify increased mitophagy as a disease marker and a therapeutic vulnerability in SRSF2P95H mutant MDS and AML.

3.
Chin Clin Oncol ; 13(2): 24, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38711177

RESUMO

BACKGROUND AND OBJECTIVE: Positron emission tomography (PET) imaging has been useful in delineating tumor volumes and allowing for improved radiation treatment. The field of PET-guided radiotherapy is rapidly growing and will have significant impact on radiotherapy delivery in the future. This narrative review provides an overview of the current state of PET-guided radiotherapy as well as the future directions of the field. METHODS: For this narrative review, PubMed was searched for articles from 2010-2023. A total of 18 keywords or phrases were searched to provide an overview of PET-guided radiotherapy, radiotracers, the role of PET-guided radiotherapy in oligometastatic disease, and biology-guided radiotherapy (BgRT). The first 300 results for each keyword were searched and relevant articles were extracted. The references of these articles were also reviewed for relevant articles. KEY CONTENT AND FINDINGS: In radiotherapy, 18F-2-fluoro-2-deoxy-D-glucose (F-FDG or FDG) is the major radiotracer for PET and when combined with computed tomography (CT) scan allows for anatomic visualization of metabolically active malignancy. Novel radiotracers are being explored to delineate certain cell types and numerous tumor metrics including metabolism, hypoxia, vascularity, and cellular proliferation. This molecular and functional imaging will provide improved tumor characterization. Through these radiotracers, radiation plans can employ dose painting by creating different dose levels based upon specific risk factors of the target volume. Additionally, biologic imaging during radiotherapy can allow for adaptation of the radiation plan based on response to treatment. Dose painting and adaptive radiotherapy should improve the therapeutic ratio through more selective dose delivery. The novel PET-linear accelerator hopes to combine these techniques and more by using radiotracers to deliver BgRT. The areas of radiotracer uptake will serve as fiducials to guide radiotherapy to themselves. This technique may prove promising in the growing area of oligometastatic radiation treatment. CONCLUSIONS: Significant challenges exist for the future of PET-guided radiotherapy. However, with the advancements being made, PET imaging is set to change the delivery of radiotherapy.


Assuntos
Tomografia por Emissão de Pósitrons , Radioterapia Guiada por Imagem , Humanos , Tomografia por Emissão de Pósitrons/métodos , Radioterapia Guiada por Imagem/métodos , Neoplasias/radioterapia , Neoplasias/diagnóstico por imagem
4.
NPJ Precis Oncol ; 8(1): 104, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760413

RESUMO

Therapeutic approaches targeting proteins on the surface of cancer cells have emerged as an important strategy for precision oncology. To capitalize on the potential impact of drugs targeting surface proteins, detailed knowledge about the expression patterns of the target proteins in tumor tissues is required. In castration-resistant prostate cancer (CRPC), agents targeting prostate-specific membrane antigen (PSMA) have demonstrated clinical activity. However, PSMA expression is lost in a significant number of CRPC tumors. The identification of additional cell surface targets is necessary to develop new therapeutic approaches. Here, we performed a comprehensive analysis of the expression heterogeneity and co-expression patterns of trophoblast cell-surface antigen 2 (TROP2), delta-like ligand 3 (DLL3), and carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) in CRPC samples from a rapid autopsy cohort. We show that DLL3 and CEACAM5 exhibit the highest expression in neuroendocrine prostate cancer (NEPC), while TROP2 is expressed across different CRPC molecular subtypes, except for NEPC. We further demonstrated that AR alterations were associated with higher expression of PSMA and TROP2. Conversely, PSMA and TROP2 expression was lower in RB1-altered tumors. In addition to genomic alterations, we show a tight correlation between epigenetic states, particularly histone H3 lysine 27 methylation (H3K27me3) at the transcriptional start site and gene body of TACSTD2 (encoding TROP2), DLL3, and CEACAM5, and their respective protein expression in CRPC patient-derived xenografts. Collectively, these findings provide insights into patterns and determinants of expression of TROP2, DLL3, and CEACAM5 with implications for the clinical development of cell surface targeting agents in CRPC.

5.
Int J Part Ther ; 11: 100009, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38757075

RESUMO

Purpose: The effectiveness of intensity-modulated proton therapy (IMPT) for esophageal cancer treated with definitive concurrent chemoradiation therapy remains inadequately explored. We investigated long-term outcomes and toxicity experienced by patients who received IMPT as part of definitive esophageal cancer treatment. Patients and Methods: We retrospectively identified and analyzed 34 patients with locally advanced esophageal cancer who received IMPT with concurrent chemotherapy as a definitive treatment regimen at The University of Texas MD Anderson Cancer Center from 2011 to 2021. The median IMPT dose was 50.4 GyRBE in 28 fractions; concurrent chemotherapy consisted of fluorouracil and/or taxane and/or platinum. Survival outcomes were determined by the Kaplan-Meier method, and toxicity was scored according to the Common Terminology Criteria for Adverse Events version 4.0. Results: The median age of all patients was 71.5 years. Most patients had stage III (cT3 cM0) adenocarcinoma of the lower esophagus. At a median follow-up time of 39 months, the 5-year overall survival rate was 41.1%; progression-free survival, 34.6%; local regional recurrence-free survival, 78.1%; and distant metastasis-free survival, 65.0%. Common acute chemoradiation therapy-related toxicities included hematologic toxicity, esophagitis (and late-onset), fatigue, weight loss, and nausea (and late-onset); grade 3 toxicity rates were 26.0% for hematologic, 18.0% for esophagitis and 9.0% for nausea. No patient had grade ≥3 wt loss or radiation pneumonitis, and no patients had pulmonary fibrosis or esophageal fistula. No grade ≥4 events were observed except for hematologic toxicity (lymphopenia) in 2 patients. Conclusion: Long-term survival and toxicity were excellent after IMPT for locally advanced esophageal cancer treated definitively with concurrent chemoradiation therapy. When available, IMPT should be offered to such patients to minimize treatment-related cardiopulmonary toxicity without sacrificing outcomes.

6.
Int J Part Ther ; 11: 100012, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38757082

RESUMO

Purpose: Evidence suggests that proton-beam therapy (PBT) results in less toxicity and postoperative complications compared to photon-based radiotherapy in patients who receive chemoradiotherapy followed by esophagectomy for cancer. Ninety-day mortality (90DM) is an important measure of the postoperative (nononcologic) outcome as proxy of quality-of-care. We hypothesize that PBT could reduce 90DM compared to photon-based radiotherapy. Materials and Methods: From a single-center retrospective database patients treated with chemoradiotherapy before esophagectomy for cancer were selected (1998-2022). Univariable logistic regression was used to study the association of radiotherapy modality with 90DM. Three separate methods were applied to adjust for confounding bias, including multivariable logistic regression, propensity score matching, and inverse probability of treatment weighting. Stratified analysis for the age threshold that maximized the difference in 90DM (ie, ≥67 vs <67 years) was performed. Results: A total of 894 eligible patients were included and 90DM was 5/202 (2.5%) in the PBT versus 29/692 (4.2%) in the photon-based radiotherapy group (P = .262). After adjustment for age and tumor location, PBT versus photon-based radiotherapy was not significantly associated with 90DM (P = .491). The 90DM was not significantly different for PBT versus photon-based radiotherapy in the propensity score matching (P = .379) and inverse probability of treatment weighting cohort (P = .426). The stratified analysis revealed that in patients aged ≥67 years, PBT was associated with decreased 90DM (1.3% vs 8.8%; P = .026). Higher age significantly increased 90DM risk within the photon-based radiotherapy (8.8% vs 2.7%; P = .001), but not within the PBT group (1.3% vs 3.2%; P = .651). Conclusion: No statistically significant difference was observed in postoperative 90DM after esophagectomy for cancer between PBT and photon-based neoadjuvant chemoradiotherapy. However, among older patients a signal was observed that PBT may reduce 90DM risk.

7.
Cureus ; 16(4): e57792, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38721201

RESUMO

Chronic idiopathic ulcers of the colon pose diagnostic challenges due to their elusive etiology and potential resemblance to other intestinal pathologies, such as cecal carcinoma. This case report outlines the clinical course of a 68-year-old female patient who presented to the emergency department (ED) with persistent right lower quadrant pain. Despite multiple hospital visits yielding varied diagnoses, a definitive diagnosis was only made following a laparoscopic partial colectomy, which revealed chronic idiopathic ulcers with transmural scarring and adhesions to adjacent small intestine loops. Histological examination demonstrated a substantial ulcer bed populated by inflammatory cells, including large stellate and spindled stromal cells within the granulation tissue, alongside lymphoid hyperplasia and scar tissue extending into the muscularis propria. The initial presentation of this case could easily be mistaken for appendicitis, diverticulitis, carcinoma, or irritable bowel syndrome, highlighting the significance of considering chronic idiopathic ulcers in the differential diagnosis of patients presenting with cecal masses.

8.
BMJ Open Respir Res ; 11(1)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38719503

RESUMO

INTRODUCTION: Bronchiectasis is a worldwide chronic lung disorder where exacerbations are common. It affects people of all ages, but especially Indigenous populations in high-income nations. Despite being a major contributor to chronic lung disease, there are no licensed therapies for bronchiectasis and there remain relatively few randomised controlled trials (RCTs) conducted in children and adults. Our RCT will address some of these unmet needs by evaluating whether the novel mucoactive agent, erdosteine, has a therapeutic role in children and adults with bronchiectasis.Our primary aim is to determine in children and adults aged 2-49 years with bronchiectasis whether regular erdosteine over a 12-month period reduces acute respiratory exacerbations compared with placebo. Our primary hypothesis is that people with bronchiectasis who regularly use erdosteine will have fewer exacerbations than those receiving placebo.Our secondary aims are to determine the effect of the trial medications on quality of life (QoL) and other clinical outcomes (exacerbation duration, time-to-next exacerbation, hospitalisations, lung function, adverse events). We will also assess the cost-effectiveness of the intervention. METHODS AND ANALYSIS: We are undertaking an international multicentre, double-blind, placebo-RCT to evaluate whether 12 months of erdosteine is beneficial for children and adults with bronchiectasis. We will recruit 194 children and adults with bronchiectasis to a parallel, superiority RCT at eight sites across Australia, Malaysia and Philippines. Our primary endpoint is the rate of exacerbations over 12 months. Our main secondary outcomes are QoL, exacerbation duration, time-to-next exacerbation, hospitalisations and lung function. ETHICS AND DISSEMINATION: The Human Research Ethics Committees (HREC) of Children's Health Queensland (for all Australian sites), University of Malaya Medical Centre (Malaysia) and St. Luke's Medical Centre (Philippines) approved the study. We will publish the results and share the outcomes with the academic and medical community, funding and relevant patient organisations. TRIAL REGISTRATION NUMBER: ACTRN12621000315819.


Assuntos
Bronquiectasia , Expectorantes , Estudos Multicêntricos como Assunto , Qualidade de Vida , Tioglicolatos , Tiofenos , Humanos , Bronquiectasia/tratamento farmacológico , Método Duplo-Cego , Tioglicolatos/uso terapêutico , Criança , Adolescente , Adulto , Adulto Jovem , Tiofenos/uso terapêutico , Pré-Escolar , Expectorantes/uso terapêutico , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Masculino , Feminino , Progressão da Doença , Resultado do Tratamento
9.
Methods Cell Biol ; 186: 25-49, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38705603

RESUMO

One of the earliest applications of flow cytometry was the measurement of DNA content in cells. This method is based on the ability to stain DNA in a stoichiometric manner (i.e., the amount of stain is directly proportional to the amount of DNA within the cell). For more than 40years, a number of studies have consistently demonstrated the utility of DNA flow cytometry as a potential diagnostic and/or prognostic tool in patients with most epithelial tumors, including pre-invasive lesions (such as dysplasia) in the gastrointestinal tract. However, its availability as a clinical test has been limited to few medical centers due to the requirement for fresh tissue in earlier studies and perceived technical demands. However, more recent studies have successfully utilized formalin-fixed paraffin-embedded (FFPE) tissue to generate high-quality DNA content histograms, demonstrating the feasibility of this methodology. This review summarizes step-by-step methods on how to perform DNA flow cytometry using FFPE tissue and analyze DNA content histograms based on the published consensus guidelines in order to assist in the diagnosis and/or risk stratification of many different epithelial tumors, with particular emphasis on dysplasia associated with Barrett's esophagus and inflammatory bowel disease.


Assuntos
Citometria de Fluxo , Neoplasias Gastrointestinais , Instabilidade Genômica , Humanos , Citometria de Fluxo/métodos , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/patologia , Instabilidade Genômica/genética , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , Fixação de Tecidos/métodos , Inclusão em Parafina/métodos , DNA/genética , DNA/análise , Trato Gastrointestinal/patologia , Trato Gastrointestinal/metabolismo , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Esôfago de Barrett/diagnóstico
10.
Curr Opin Ophthalmol ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38700496

RESUMO

PURPOSE OF REVIEW: To review corneal crosslinking for keratoconus and corneal ectasia, and recent developments in the field. This study will review the mechanism of crosslinking, clinical approaches, current results, and potential future innovations. RECENT FINDINGS: Corneal crosslinking for keratoconus was first approved by U.S. FDA in 2016. Recent studies have confirmed the general long-term efficacy of the procedure in decreasing progression of keratoconus and corneal ectasia. New types of crosslinking protocols, such as transepithelial treatments, are under investigation. In addition, adjunctive procedures have been developed to improve corneal contour and visual function in these patients. SUMMARY: Crosslinking has been found to be well tolerated and effective with the goal of decreasing progression of ectatic corneal diseases, keratoconus and corneal ectasia after refractive surgery. Studies have shown its long-term efficacy. New techniques of crosslinking and adjunctive procedures may further improve treatments and results.

11.
Child Abuse Negl ; 153: 106834, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704885

RESUMO

BACKGROUND: Adverse childhood experiences (ACEs) represent a key risk factor for suicidal thoughts and behaviors among adolescents. However, the intervening mechanisms linking ACEs and suicidality, and whether such processes vary by gender, remain underexplored. OBJECTIVE: The present study examines whether the relationships between ACEs and the likelihood of experiencing suicidal thoughts and attempting suicide are indirect through depressive symptoms and low self-control. This study also investigates whether these direct and indirect paths might be moderated by gender. PARTICIPANTS AND SETTING: The analyses make use of data on a statewide representative sample of students enrolled in public high schools in Florida (N = 23,078) from the 2022 Florida Youth Substance Abuse Survey (FYSAS). METHODS: Generalized structural equation modeling (GSEM) was used to estimate the direct and indirect effects of ACEs on the likelihood of suicidal thoughts and attempting suicide. The indirect effects were assessed using bootstrapping, and between-gender differences in the coefficients were tested. RESULTS: ACEs has direct associations with depressive symptoms, low self-control, and both suicidality outcomes. The effects of ACEs on suicidal thoughts are indirect through both depressive symptoms and low self-control, and the effects of ACEs on suicide attempts are indirect through depressive symptoms. Limited gender differences in these pathways emerge. CONCLUSIONS: For male and female youth, ACEs are associated with heightened depression symptoms and reduced self-control, and both of these factors partially explain the previously established relationship between ACEs and suicidality.

12.
Clin J Pain ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38751011

RESUMO

OBJECTIVES: Different types of spinal cord stimulation (SCS) have now been evaluated for the management of chronic non-surgical refractory back pain (NSRBP). A direct comparison between the different types of SCS or between closed-loop SCS with conventional medical management (CMM) for patients with NSRBP has not been previously conducted, and therefore, their relative effectiveness and cost-effectiveness remain unknown. The aim of this study was to perform a systematic review, network meta-analysis (NMA) and economic evaluation of closed-loop SCS compared with fixed-output SCS and CMM for patients with NSRBP. METHODS: Databases were searched to 8th September 2023. Randomised controlled trials of SCS for NSRBP were included. Results of studies were combined using fixed-effect NMA models. A cost-utility analysis was performed from the perspective of the UK National Health Service with results reported as incremental cost per quality-adjusted life-year (QALY). RESULTS: Closed-loop SCS resulted in statistically and clinically significant reductions in pain intensity (mean difference [MD] 32.72 [95% CrI 15.69-49.78]) and improvements in secondary outcomes compared to fixed-output SCS at 6-months follow-up. Compared to CMM, both closed-loop and fixed-output SCS result in statistically and clinically significant reductions in pain intensity (closed-loop SCS vs. CMM MD 101.58 [95% CrI 83.73-119.48]; fixed-output SCS versus CMM MD 68.86 [95% CrI 63.43-74.31]) and improvements in secondary outcomes. Cost-utility analysis shows that closed-loop SCS dominates fixed-output SCS and CMM, and fixed-output SCS also dominates CMM. DISCUSSION: Current evidence shows that closed-loop and fixed-output SCS provide more benefits and are cost-saving compared to CMM for patients with NSRBP.

13.
Neurosurg Focus ; 56(5): E9, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38691864

RESUMO

OBJECTIVE: Chordomas are rare tumors of the skull base and spine believed to arise from the vestiges of the embryonic notochord. These tumors are locally aggressive and frequently recur following resection and adjuvant radiotherapy. Proton therapy has been introduced as a tissue-sparing option because of the higher level of precision that proton-beam techniques offer compared with traditional photon radiotherapy. This study aimed to compare recurrence in patients with chordomas receiving proton versus photon radiotherapy following resection by applying tree-based machine learning models. METHODS: The clinical records of all patients treated with resection followed by adjuvant proton or photon radiotherapy for chordoma at Mayo Clinic were reviewed. Patient demographics, type of surgery and radiotherapy, tumor recurrence, and other variables were extracted. Decision tree classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split. RESULTS: Fifty-three patients with a mean ± SD age of 55.2 ± 13.4 years receiving surgery and adjuvant proton or photon therapy to treat chordoma were identified; most patients were male. Gross-total resection was achieved in 54.7% of cases. Proton therapy was the most common adjuvant radiotherapy (84.9%), followed by conventional or external-beam radiation therapy (9.4%) and stereotactic radiosurgery (5.7%). Patients receiving proton therapy exhibited a 40% likelihood of having recurrence, significantly lower than the 88% likelihood observed in those treated with nonproton therapy. This was confirmed on logistic regression analysis adjusted for extent of tumor resection and tumor location, which revealed that proton adjuvant radiotherapy was associated with a decreased risk of recurrence (OR 0.1, 95% CI 0.01-0.71; p = 0.047) compared with photon therapy. The decision tree algorithm predicted recurrence with an accuracy of 90% (95% CI 55.5%-99.8%), with the lowest risk of recurrence observed in patients receiving gross-total resection with adjuvant proton therapy (23%). CONCLUSIONS: Following resection, adjuvant proton therapy was associated with a lower risk of chordoma recurrence compared with photon therapy. The described machine learning models were able to predict tumor progression based on the extent of tumor resection and adjuvant radiotherapy modality used.


Assuntos
Cordoma , Recidiva Local de Neoplasia , Fótons , Terapia com Prótons , Neoplasias da Coluna Vertebral , Humanos , Cordoma/radioterapia , Cordoma/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/radioterapia , Terapia com Prótons/métodos , Radioterapia Adjuvante/métodos , Adulto , Idoso , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Fótons/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
14.
Proc Natl Acad Sci U S A ; 121(22): e2317230121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768344

RESUMO

Efforts to develop an HIV-1 vaccine include those focusing on conserved structural elements as the target of broadly neutralizing monoclonal antibodies. MAb D5 binds to a highly conserved hydrophobic pocket on the gp41 N-heptad repeat (NHR) coiled coil and neutralizes through prevention of viral fusion and entry. Assessment of 17-mer and 36-mer NHR peptides presenting the D5 epitope in rodent immunogenicity studies showed that the longer peptide elicited higher titers of neutralizing antibodies, suggesting that neutralizing epitopes outside of the D5 pocket may exist. Although the magnitude and breadth of neutralization elicited by NHR-targeting antigens are lower than that observed for antibodies directed to other epitopes on the envelope glycoprotein complex, it has been shown that NHR-directed antibodies are potentiated in TZM-bl cells containing the FcγRI receptor. Herein, we report the design and evaluation of covalently stabilized trimeric 51-mer peptides encompassing the complete gp41 NHR. We demonstrate that these peptide trimers function as effective antiviral entry inhibitors and retain the ability to present the D5 epitope. We further demonstrate in rodent and nonhuman primate immunization studies that our 51-mer constructs elicit a broader repertoire of neutralizing antibody and improved cross-clade neutralization of primary HIV-1 isolates relative to 17-mer and 36-mer NHR peptides in A3R5 and FcγR1-enhanced TZM-bl assays. These results demonstrate that sensitive neutralization assays can be used for structural enhancement of moderately potent neutralizing epitopes. Finally, we present expanded trimeric peptide designs which include unique low-molecular-weight scaffolds that provide versatility in our immunogen presentation strategy.


Assuntos
Vacinas contra a AIDS , Anticorpos Neutralizantes , Anticorpos Anti-HIV , Proteína gp41 do Envelope de HIV , HIV-1 , Proteína gp41 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/química , HIV-1/imunologia , Animais , Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Humanos , Camundongos , Epitopos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Peptídeos/imunologia , Peptídeos/química , Feminino , Anticorpos Monoclonais/imunologia
15.
Am Heart J ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38740532

RESUMO

BACKGROUND: The STRONG-HF trial showed that high-intensity care (HIC) consisting of rapid up-titration of guideline-directed medical therapy (GDMT) and close follow-up reduced all-cause death or heart failure (HF) readmission at 180 days compared to usual care (UC). We hypothesized that significant differences in patient characteristics, management, and outcomes over the enrolment period may exist. METHODS: Two groups of the 1,078 patients enrolled in STRONG-HF were created according to the order of enrolment within center. The early group consisted of the first 10 patients enrolled at each center (N = 342) and the late group consisted of the following patients (N = 736). RESULTS: Late enrollees were younger, had more frequently reduced ejection fraction, slightly lower NT-proBNP and creatinine levels compared with early enrollees. The primary outcome occurred less frequently in early compared to late enrollees (15% vs. 21%, aHR 0.65, 95% CI 0.42-0.99, P = .044). No treatment-by-enrolment interaction was seen in respect to the average percentage of optimal dose of GDMT after randomization, which was consistently higher in early and late patients randomized to HIC compared to UC. The higher use of renin-angiotensin-inhibitors in the HIC arm was more pronounced in the late enrollees both after randomization (interaction-P = .013) and at 90 days (interaction-P < .001). No interaction was observed for safety events. Patients randomized late to UC displayed a trend toward more severe outcomes (26% vs. 16%, P = .10), but the efficacy of HIC showed no interaction with the enrolment group (aHR 0.77, 95% CI 0.35-1.67 in early and 0.58, 95% CI 0.40-0.83 in late enrollees, adjusted interaction-P = .51) with similar outcomes in the HIC arm in late and early enrollees (16% vs. 13%, P = .73). CONCLUSIONS: Late enrollees have different clinical characteristics and higher event rates compared to early enrollees. GDMT implementation in the HIC arm robustly achieved similar doses with consistent efficacy in early and late enrollees, mitigating the higher risk of adverse outcome in late enrollees. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03412201.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38779750

RESUMO

Alpha-1-microglobulin (A1M) is a circulating glycoprotein with antioxidant, heme binding and mitochondrial protection properties. The investigational drug RMC-035, a modified therapeutic A1M protein, was assessed for biodistribution and pharmacological activity in a broad set of in vitro and in vivo experiments, supporting its clinical development. Efficacy and treatment posology was assessed in various models of kidney ischemia and reperfusion injury (IRI). Real-time glomerular filtration rate, functional renal biomarkers, tubular injury biomarkers (NGAL and KIM-1) and histopathology were evaluated. Fluorescently labeled RMC-035 was used to assess biodistribution. RMC-035 demonstrated consistent and reproducible kidney protection in rat IRI models, also in a model of IRI imposed on renal impairment, and in a mouse IRI model where it reduced mortality. Its pharmacological activity was most pronounced with combined dosing pre- and post-ischemia, and weaker with either pre- or post-ischemia dosing alone. RMC-035 rapidly distributed to the kidneys via glomerular filtration and selective luminal uptake by proximal tubular cells. IRI-induced expression of kidney heme oxygenase-1 was inhibited by RMC-035, consistent with its antioxidative properties. RMC-035 also dampened IRI-associated inflammation and improved mitochondrial function shown by tubular autofluorescence. Taken together, the efficacy of RMC-035 is congruent with its targeted mechanism(s) and biodistribution profile and supports its further clinical evaluation as a novel kidney-protective therapy.

17.
Elife ; 132024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747717

RESUMO

Invertebrates use the endoribonuclease Dicer to cleave viral dsRNA during antiviral defense, while vertebrates use RIG-I-like Receptors (RLRs), which bind viral dsRNA to trigger an interferon response. While some invertebrate Dicers act alone during antiviral defense, Caenorhabditis elegans Dicer acts in a complex with a dsRNA binding protein called RDE-4, and an RLR ortholog called DRH-1. We used biochemical and structural techniques to provide mechanistic insight into how these proteins function together. We found RDE-4 is important for ATP-independent and ATP-dependent cleavage reactions, while helicase domains of both DCR-1 and DRH-1 contribute to ATP-dependent cleavage. DRH-1 plays the dominant role in ATP hydrolysis, and like mammalian RLRs, has an N-terminal domain that functions in autoinhibition. A cryo-EM structure indicates DRH-1 interacts with DCR-1's helicase domain, suggesting this interaction relieves autoinhibition. Our study unravels the mechanistic basis of the collaboration between two helicases from typically distinct innate immune defense pathways.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , RNA de Cadeia Dupla , Ribonuclease III , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , RNA de Cadeia Dupla/metabolismo , Ribonuclease III/metabolismo , Ribonuclease III/química , Ribonuclease III/genética , Microscopia Crioeletrônica , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/genética , RNA Helicases/metabolismo , RNA Helicases/genética , RNA Helicases/química , Ligação Proteica , Trifosfato de Adenosina/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteína DEAD-box 58/metabolismo , Proteína DEAD-box 58/genética , Proteína DEAD-box 58/química
18.
Gastro Hep Adv ; 3(3): 326-332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765199

RESUMO

BACKGROUND AND AIMS: The prevalence of inflammatory bowel disease (IBD) is increasing globally. In this context, identifying risk factors for severe disease is important. We examined how race/ethnicity and immigration status influence IBD manifestations, treatments, and outcomes in a diverse, tertiary-care safety-net hospital. METHODS: We conducted a single-center retrospective review of all IBD inpatients and outpatients treated from 1997-2017. Using logistic regression modeling, we compared disease onset, treatment, and outcomes by race (White, Black, Hispanic, or Asian) and immigration status (US-born vs foreign-born). RESULTS: A total of 577 patients were identified, of which 29.8% were White, 27.4% were Hispanic, 21.7% were Black, and 13.0% were Asian. Compared to Whites, Asians were more likely to be male (odds ratio [OR] 2.63, 95% confidence interval [CI]: 1.45, 5.00), whereas Blacks were more likely to be diagnosed with Crohn's disease (OR 1.75, 95% CI: 1.10, 2.77) and more likely to undergo IBD-related intestinal resection (OR 2.49, 95% CI: 1.40, 4.50). Compared to US-born patients, foreign-born patients were more likely to be diagnosed with ulcerative colitis (OR 1.77, 95% CI: 1.04, 3.02). They were also less likely to be diagnosed before 16 years of age (OR 0.19, 95% CI: 0.08, 0.41), to have undergone intestinal resections (OR 0.39, 95% CI: 0.19, 0.83), to have received biologics (OR 0.43, 95% CI: 0.25, 0.76), or to have had dermatologic manifestations (OR 0.12, 95% CI: 0.03, 0.41). CONCLUSION: IBD phenotype varies by race, although foreign-born patients of all races show evidence of later-onset and milder disease. These findings may aid in disease prognostication and clinical management and, furthermore, may provide insight into intrinsic and environmental influences on IBD pathogenesis.

19.
eNeurologicalSci ; 35: 100502, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38770222

RESUMO

A case-control study of sporadic amyotrophic lateral sclerosis (ALS) in a mountainous village in the French Alps discovered an association of cases with a history of eating wild fungi (false morels) collected locally and initially identified and erroneously reported as Gyromitra gigas. Specialist re-examination of dried specimens of the ALS-associated fungi demonstrated they were members of the G. esculenta group, namely G. venenata and G. esculenta, species that have been reported to contain substantially higher concentrations of gyromitrin than present in G. gigas. Gyromitrin is metabolized to monomethylhydrazine, which is responsible not only for the acute oral toxic and neurotoxic properties of false morels but also has genotoxic potential with proposed mechanistic relevance to the etiology of neurodegenerative disease. Most ALS patients had a slow- or intermediate-acetylator phenotype predicted by N-acetyltransferase-2 (NAT2) genotyping, which would increase the risk for neurotoxic and genotoxic effects of gyromitrin metabolites.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38772709

RESUMO

Biomarkers are critical to the staging and diagnosis of type 1 diabetes (T1D). Functional biomarkers offer insights into T1D immunopathogenesis and are often revealed using "omics" approaches that integrate multiple measures to identify involved pathways and functions. Application of the omics biomarker discovery may enable personalized medicine approaches to circumvent the more recently appreciated heterogeneity of T1D progression and treatment. Use of omics to define functional biomarkers is still in its early years, yet findings to date emphasize the role of cytokine signaling and adaptive immunity in biomarkers of progression and response to therapy. Here, we share examples of the use of omics to define functional biomarkers focusing on two signatures, T-cell exhaustion and T-cell help, which have been associated with outcomes in both the natural history and treatment contexts.

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