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1.
Artículo en Inglés | MEDLINE | ID: mdl-38735015

RESUMEN

BACKGROUND: Treating cancer-associated venous thromboembolism (CAT) with anticoagulation prevents recurrent venous thromboembolism (rVTE), but increases bleeding risk. OBJECTIVES: To compare incidence of rVTE, major bleeding, and all-cause mortality for rivaroxaban versus low molecular weight heparin (LMWH) in patients with CAT. METHODS: We developed a cohort study using Swedish national registers 2013-2019. Patients with CAT (venous thromboembolism within 6 months of cancer diagnosis) were included. Those with other indications or with high bleeding risk cancers were excluded (according to guidelines). Follow-up was from index-CAT until outcome, death, emigration, or end of study. Incidence rates (IR) per 1000 person-years with 95% confidence interval (CI) and propensity score overlap-weighted hazard ratios (HRs) for rivaroxaban versus LMWH were estimated. RESULTS: We included 283 patients on rivaroxaban and 5181 on LMWH. The IR for rVTE was 68.7 (95% CI 40.0-109.9) for rivaroxaban, compared with 91.6 (95% CI 81.9-102.0) for LMWH, with adjusted HR 0.77 (95% CI 0.43-1.35). The IR for major bleeding was 23.5 (95% CI 8.6-51.1) for rivaroxaban versus 49.2 (95% CI 42.3-56.9) for LMWH, with adjusted HR 0.62 (95% CI 0.26-1.49). The IR for all-cause mortality was 146.8 (95% CI 103.9-201.5) for rivaroxaban and 565.6 (95% CI 541.8-590.2) for LMWH with adjusted HR 0.48 (95% CI 0.34-0.67). CONCLUSIONS: Rivaroxaban performed similarly to LMWH for patients with CAT for rVTE and major bleeding. An all-cause mortality benefit was observed for rivaroxaban which potentially may be attributed to residual confounding. TRIAL REGISTRATION NUMBER: NCT05150938 (Registered 9 December 2021).

2.
BMC Med Imaging ; 24(1): 109, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745329

RESUMEN

BACKGROUND: Spinal deformations, except for acute injuries, are among the most frequent reasons for visiting an orthopaedic specialist and musculoskeletal treatment in adults and adolescents. Data on the morphology and anatomical structures of the spine are therefore of interest to orthopaedics, physicians, and medical scientists alike, in the broad field from diagnosis to therapy and in research. METHODS: Along the course of developing supplementary methods that do not require the use of ionizing radiation in the assessment of scoliosis, twenty CT scans from females and males with various severity of spinal deformations and body shape have been analysed with respect to the transverse distances between the vertebral body and the spinous process end tip and the skin, respectively, at thoracic and lumbar vertebral levels. Further, the locations of the vertebral bodies have been analysed in relation to the patient's individual body shape and shown together with those from other patients by normalization to the area encompassed by the transverse body contour. RESULTS: While the transverse distance from the vertebral body to the skin varies between patients, the distances from the vertebral body to the spinous processes end tips tend to be rather similar across different patients of the same gender. Tables list the arithmetic mean distances for all thoracic and lumbar vertebral levels and for different regions upon grouping into mild, medium, and strong spinal deformation and according to the range of spinal deformation. CONCLUSIONS: The distances, the clustering of the locations of the vertebral bodies as a function of the vertebral level, and the trends therein could in the future be used in context with biomechanical modeling of a patient's individual spinal deformation in scoliosis assessment using 3D body scanner images during follow-up examinations.


Asunto(s)
Vértebras Lumbares , Escoliosis , Vértebras Torácicas , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Vértebras Torácicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Vértebras Lumbares/diagnóstico por imagen , Adulto , Adolescente , Escoliosis/diagnóstico por imagen , Persona de Mediana Edad , Anciano , Adulto Joven
3.
Cureus ; 16(4): e57530, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38707110

RESUMEN

Chronic mesenteric ischemia (CMI) is a vascular disorder primarily caused by atherosclerosis, resulting in intestinal ischemia. While endovascular treatment has become the primary modality for most patients, open mesenteric revascularization remains crucial for complex cases. We present a case of CMI in a patient with critical ischemia, leading to small bowel necrosis, where the endovascular recanalization failed and a surgical approach was needed. A supraceliac antegrade aortomesenteric bypass was performed, and successful revascularization of intestinal circulation was achieved. A novel prefabricated bovine pericardium tube was used as a graft, and the bypass was placed behind the pancreas to ensure maximal isolation from the contaminated abdominal cavity. Despite the intestinal revascularization, in the early postoperative period, the overall condition of the patient worsened with obvious signs of peritonitis. The second look operation revealed a ruptured gallbladder with severe biliary peritonitis, likely caused by the preceding splanchnic ischemia. A cholecystectomy, lavage, and drainage were performed. No further intestinal necrosis was observed, and the bowel passage was restored with latero-lateral jejuno-lejunostomy. The follow-up of the patient showed no signs of graft infection. Despite the complications, the patient's postoperative period was stable, and he was discharged on day sixteen. Regular follow-ups confirmed an excellent patency of the bypass.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38725227

RESUMEN

INTRODUCTION: Although prior studies indicate that a QTc > 500 ms on a single baseline 12-lead electrocardiogram (ECG) is associated with significantly increased risk of arrhythmic events in long QT syndrome (LQTS), less is known about the risk of persistent QT prolongation. We sought to determine QTc persistence and its prognostic effect on breakthrough cardiac events (BCEs) among pediatric patients treated for LQTS. METHODS: We performed a retrospective analysis of 433 patients with LQTS evaluated, risk-stratified, and undergoing active guideline-based LQTS treatment between 1999 and 2019. BCEs were defined as arrhythmogenic syncope/seizure, sudden cardiac arrest (SCA), appropriate VF-terminating ICD shock, and sudden cardiac death (SCD). RESULTS: During the median follow-up of 5.5 years (interquartile range [IQR] = 3-9), 32 (7%) patients experienced a total of 129 BCEs. A maximum QTc threshold of 520 ms and median QTc threshold of 490 ms were determined to be strong predictors for BCEs. A landmark analysis controlling for age, sex, genotype, and symptomatic status demonstrated models utilizing both the median QTc and maximum QTc demonstrated the highest discriminatory value (c-statistic = 0.93-0.95). Patients in the high-risk group (median QTc > 490 ms and maximum QTc > 520 ms) had a significantly lower BCE free survival (70%-81%) when compared to patients in both medium-risk (93%-97%) and low-risk (98%-99%) groups. CONCLUSIONS: The risk of BCE among patients treated for LQTS increases not only based upon their maximum QTc, but also their median QTc (persistence of QTc prolongation). Patients with a maximum QTc > 520 ms and median QTc > 490 ms over serial 12-lead ECGs are at the highest risk of BCE while on guideline-directed medical therapy.

5.
J Card Fail ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38697466

RESUMEN

BACKGROUND: Differences in demographics, risk factors, and clinical characteristics may contribute to variation in men and women in terms of prevalence, clinical setting, and outcomes associated with worsening heart failure (WHF) events. OBJECTIVES: To describe sex-based differences in the epidemiology, clinical characteristics, and outcomes associated with WHF events across clinical settings. METHODS: We examined adults diagnosed with HF from 2010-2019 within a large, integrated healthcare delivery system. Electronic health record data were accessed for hospitalizations, emergency department (ED) visits/observation stays, and outpatient encounters. WHF was identified using validated natural language processing algorithms and defined as ≥1 symptom, ≥2 objective findings (including ≥1 sign), and ≥1 change in HF-related therapy. Incidence rates and associated outcomes for WHF were compared across care setting by sex. RESULTS: We identified 1,122,368 unique clinical encounters with a diagnosis code for HF, with 124,479 meeting WHF criteria. These WHF encounters existed among 102,116 patients, of which 48,543 (47.5%) were women and 53,573 (52.5%) were men. Women experiencing WHF were older and more likely to have HF with preserved ejection fraction compared to men. The clinical settings of WHF were similar among women and men: hospitalizations (36.8% vs. 37.7%), ED visits or observation stays (11.8% vs. 13.4%), and outpatient encounters (4.4% vs. 4.9%). Women had lower odds of 30-day mortality following an index hospitalization (adjusted odds ratio [aOR] 0.88, 95% confidence interval [CI] 0.83-0.93) or ED visit/observation stay (aOR 0.86, 95% 0.75-0.98) for WHF. CONCLUSION: Women and men contribute similarly to WHF events across diverse clinical settings despite marked differences in age and left ventricular ejection fraction.

6.
Sci Rep ; 14(1): 10938, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740878

RESUMEN

Plant disease often increases with N, decreases with CO2, and increases as biodiversity is lost (i.e., the dilution effect). Additionally, all these factors can indirectly alter disease by changing host biomass and hence density-dependent disease transmission. Yet over long periods of time as communities undergo compositional changes, these biomass-mediated pathways might fade, intensify, or even reverse in direction. Using a field experiment that has manipulated N, CO2, and species richness for over 20 years, we compared severity of a specialist rust fungus (Puccinia andropogonis) on its grass host (Andropogon gerardii) shortly after the experiment began (1999) and twenty years later (2019). Between these two sampling periods, two decades apart, we found that disease severity consistently increased with N and decreased with CO2. However, the relationship between diversity and disease reversed from a dilution effect in 1999 (more severe disease in monocultures) to an amplification effect in 2019 (more severe disease in mixtures). The best explanation for this reversal centered on host density (i.e., aboveground biomass), which was initially highest in monoculture, but became highest in mixtures two decades later. Thus, the diversity-disease pattern reversed, but disease consistently increased with host biomass. These results highlight the consistency of N and CO2 as drivers of plant disease in the Anthropocene and emphasize the critical role of host biomass-despite potentially variable effects of diversity-for relationships between biodiversity and disease.


Asunto(s)
Biodiversidad , Biomasa , Dióxido de Carbono , Nitrógeno , Enfermedades de las Plantas , Dióxido de Carbono/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Nitrógeno/metabolismo , Basidiomycota/genética , Poaceae/microbiología
7.
ISME J ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38722823

RESUMEN

Physiological responses of soil microorganisms to global warming are important for soil ecosystem function and the terrestrial carbon cycle. Here, we investigate the effects of weeks, years, and decades of soil warming across seasons and time on the microbial protein biosynthesis machineries (i.e. ribosomes), the most abundant cellular macromolecular complexes, using RNA:DNA and RNA:MBC (microbial biomass carbon) ratios as proxies for cellular ribosome contents. We compared warmed soils and non-warmed controls of 15 replicated subarctic grassland and forest soil temperature gradients subject to natural geothermal warming. RNA:DNA ratios tended to be lower in the warmed soils during summer and autumn, independent of warming duration (6 weeks, 8-14 years, > 50 years), warming intensity (+3°C, +6°C, +9°C), and ecosystem type. With increasing temperatures RNA:MBC ratios were also decreasing. Additionally, seasonal RNA:DNA ratios of the consecutively sampled forest showed the same temperature-driven pattern. This suggests that subarctic soil microorganisms are depleted of ribosomes under warm conditions and the lack of consistent relationships with other physicochemical parameters besides temperature further suggests temperature as key driver. Furthermore, in incubation experiments, we measured significantly higher CO2 emission rates per unit of RNA from short- and long-term warmed soils compared to non-warmed controls. In conclusion, ribosome reduction may represent a widespread microbial physiological response to warming that offers a selective advantage at higher temperatures, as energy and matter can be reallocated from ribosome synthesis to other processes including substrate uptake and turnover. This way, ribosome reduction could have a substantial effect on soil carbon dynamics.

8.
J Vet Dent ; : 8987564241248042, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693764

RESUMEN

The study investigated whether malondialdehyde (MDA), a biomarker for oxidative stress, can be used as a viable parameter in dog saliva for the diagnosis or early detection of periodontal disease (PD). Saliva MDA concentrations were measured preoperatively in dogs diagnosed with PD during dental prophylaxis and compared with those of dentally healthy dogs. 35 dogs were included in the study. The average MDA concentration was 270 ng/ml (range 27-633) in the dogs without PD (n = 10) and 183 (36-833) ng/ml (ng/ml) in the dogs with PD (n = 25). The maximum MDA concentration in the study group (PD ≥1) was 833 ng/ml, which was significantly higher than in the study group (PD = 0) (p<0.05). The study showed that salivary MDA concentrations could not distinguish between healthy dogs and those with PD.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38696213

RESUMEN

This Viewpoint shares the experience of a single Otolaryngology−Head & Neck Surgery residency program that faced the scheduling challenges of having nearly a quarter of its residents expecting a child and on parental leave.

10.
Stereotact Funct Neurosurg ; : 1-16, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38697047

RESUMEN

BACKGROUND: Deep brain stimulation (DBS) is an effective therapy for Parkinson's disease (PD), but disparities exist in access to DBS along gender, racial, and socioeconomic lines. SUMMARY: Women are underrepresented in clinical trials and less likely to undergo DBS compared to their male counterparts. Racial and ethnic minorities are also less likely to undergo DBS procedures, even when controlling for disease severity and other demographic factors. These disparities can have significant impacts on patients' access to care, quality of life, and ability to manage their debilitating movement disorders. KEY MESSAGES: Addressing these disparities requires increasing patient awareness and education, minimizing barriers to equitable access, and implementing diversity and inclusion initiatives within the healthcare system. In this systematic review, we first review literature discussing gender, racial, and socioeconomic disparities in DBS access and then propose several patient, provider, community, and national-level interventions to improve DBS access for all populations.

11.
Laryngoscope ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738796

RESUMEN

OBJECTIVES: Animal models for laryngotracheal stenosis (LTS) are critical to understand underlying mechanisms and study new therapies. Current animal models for LTS are limited by small airway sizes compared to human. The objective of this study was to develop and validate a novel, large animal ovine model for LTS. METHODS: Sheep underwent either bleomycin-coated polypropylene brush injury to the subglottis (n = 6) or airway stent placement (n = 2) via suspension microlaryngoscopy. Laryngotracheal complexes were harvested 4 weeks following injury or stent placement. For the airway injury group, biopsies (n = 3 at each site) were collected of tracheal scar and distal normal regions, and analyzed for fibrotic gene expression. Lamina propria (LP) thickness was compared between injured and normal areas of trachea. RESULTS: No mortality occurred in sheep undergoing airway injury or stent placement. There was no migration of tracheal stents. After protocol optimization, LP thickness was significantly increased in injured trachea (Sheep #3: 529.0 vs. 850.8 um; Sheep #4: 933.0 vs. 1693.2 um; Sheep #5: 743.7 vs. 1378.4 um; Sheep #6: 305.7 vs. 2257.6 um). A significant 62-fold, 20-fold, 16-fold, 16-fold, and 9-fold change of COL1, COL3, COL5, FN1, and TGFB1 was observed in injured scar specimen relative to unaffected airway, respectively. CONCLUSION: An ovine LTS model produces histologic and transcriptional changes consistent with fibrosis seen in human LTS. Airway stent placement in this model is safe and feasible. This large airway model is a reliable and reproducible method to assess the efficacy of novel LTS therapies prior to clinical translation. LEVEL OF EVIDENCE: N/A Laryngoscope, 2024.

12.
Nat Med ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740997

RESUMEN

How human genetic variation contributes to vaccine effectiveness in infants is unclear, and data are limited on these relationships in populations with African ancestries. We undertook genetic analyses of vaccine antibody responses in infants from Uganda (n = 1391), Burkina Faso (n = 353) and South Africa (n = 755), identifying associations between human leukocyte antigen (HLA) and antibody response for five of eight tested antigens spanning pertussis, diphtheria and hepatitis B vaccines. In addition, through HLA typing 1,702 individuals from 11 populations of African ancestry derived predominantly from the 1000 Genomes Project, we constructed an imputation resource, fine-mapping class II HLA-DR and DQ associations explaining up to 10% of antibody response variance in our infant cohorts. We observed differences in the genetic architecture of pertussis antibody response between the cohorts with African ancestries and an independent cohort with European ancestry, but found no in silico evidence of differences in HLA peptide binding affinity or breadth. Using immune cell expression quantitative trait loci datasets derived from African-ancestry samples from the 1000 Genomes Project, we found evidence of differential HLA-DRB1 expression correlating with inferred protection from pertussis following vaccination. This work suggests that HLA-DRB1 expression may play a role in vaccine response and should be considered alongside peptide selection to improve vaccine design.

13.
ESC Heart Fail ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741373

RESUMEN

AIMS: Worsening heart failure (WHF) events occurring in non-inpatient settings are becoming increasingly recognized, with implications for prognostication. We evaluate the performance of a natural language processing (NLP)-based approach compared with traditional diagnostic coding for non-inpatient clinical encounters and left ventricular ejection fraction (LVEF). METHODS AND RESULTS: We compared characteristics for encounters that did vs. did not meet WHF criteria, stratified by care setting [i.e. emergency department (ED) and observation stay]. Overall, 8407 (22%) encounters met NLP-based criteria for WHF (3909 ED visits and 4498 observation stays). The use of an NLP-derived definition adjudicated 3983 (12%) of non-primary HF diagnoses as meeting consensus definitions for WHF. The most common diagnosis indicated in these encounters was dyspnoea. Results were primarily driven by observation stays, in which 2205 (23%) encounters with a secondary HF diagnosis met the WHF definition by NLP. CONCLUSIONS: The use of standard claims-based adjudication for primary diagnosis in the non-inpatient setting may lead to misclassification of WHF events in the ED and overestimate observation stays. Primary diagnoses alone may underestimate the burden of WHF in non-hospitalized settings.

14.
JACC Heart Fail ; 2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38678466

RESUMEN

BACKGROUND: Heart failure (HF) is a leading cause of hospitalization in the United States. Decongestion remains a central goal of inpatient management, but contemporary decongestion practices and associated weight loss have not been well characterized nationally. OBJECTIVES: This study aimed to describe contemporary inpatient diuretic practices and clinical predictors of weight loss in patients hospitalized for HF. METHODS: The authors identified HF hospitalizations from 2015 to 2022 in a U.S. national database aggregating deidentified patient-level electronic health record data across 31 geographically diverse community-based health systems. The authors report patient characteristics and inpatient weight change as a primary indicator of decongestion. Predictors of weight loss were evaluated using multivariable models. Temporal trends in inpatient diuretic practices, including augmented diuresis strategies such as adjunctive thiazides and continuous diuretic infusions, were assessed. RESULTS: The study cohort included 262,673 HF admissions across 165,482 unique patients. The median inpatient weight loss was 5.3 pounds (Q1-Q3: 0.0-12.8 pounds) or 2.4 kg (Q1-Q3: 0.0-5.8 kg). Discharge weight was higher than admission weight in 20% of encounters. An increase of ≥0.3 mg/dL in serum creatinine from admission to inpatient peak occurred in >30% of hospitalizations and was associated with less weight loss. Adjunctive diuretic agents were utilized in <20% of encounters but were associated with greater weight loss. CONCLUSIONS: In a large-scale U.S. community-based cohort study of HF hospitalizations, estimated weight loss from inpatient decongestion remains highly variable, with weight gain observed across many admissions. Augmented diuresis strategies were infrequently used. Comparative effectiveness trials are needed to establish optimal strategies for inpatient decongestion for acute HF.

15.
Comput Biol Med ; 175: 108410, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38678938

RESUMEN

Latent diffusion models (LDMs) have emerged as a state-of-the-art image generation method, outperforming previous Generative Adversarial Networks (GANs) in terms of training stability and image quality. In computational pathology, generative models are valuable for data sharing and data augmentation. However, the impact of LDM-generated images on histopathology tasks compared to traditional GANs has not been systematically studied. We trained three LDMs and a styleGAN2 model on histology tiles from nine colorectal cancer (CRC) tissue classes. The LDMs include 1) a fine-tuned version of stable diffusion v1.4, 2) a Kullback-Leibler (KL)-autoencoder (KLF8-DM), and 3) a vector quantized (VQ)-autoencoder deploying LDM (VQF8-DM). We assessed image quality through expert ratings, dimensional reduction methods, distribution similarity measures, and their impact on training a multiclass tissue classifier. Additionally, we investigated image memorization in the KLF8-DM and styleGAN2 models. All models provided a high image quality, with the KLF8-DM achieving the best Frechet Inception Distance (FID) and expert rating scores for complex tissue classes. For simpler classes, the VQF8-DM and styleGAN2 models performed better. Image memorization was negligible for both styleGAN2 and KLF8-DM models. Classifiers trained on a mix of KLF8-DM generated and real images achieved a 4% improvement in overall classification accuracy, highlighting the usefulness of these images for dataset augmentation. Our systematic study of generative methods showed that KLF8-DM produces the highest quality images with negligible image memorization. The higher classifier performance in the generatively augmented dataset suggests that this augmentation technique can be employed to enhance histopathology classifiers for various tasks.


Asunto(s)
Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos
16.
Eur Heart J ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38606889

RESUMEN

Clinical risk scores based on traditional risk factors of atherosclerosis correlate imprecisely to an individual's complex pathophysiological predisposition to atherosclerosis and provide limited accuracy for predicting major adverse cardiovascular events (MACE). Over the past two decades, computed tomography scanners and techniques for coronary computed tomography angiography (CCTA) analysis have substantially improved, enabling more precise atherosclerotic plaque quantification and characterization. The accuracy of CCTA for quantifying stenosis and atherosclerosis has been validated in numerous multicentre studies and has shown consistent incremental prognostic value for MACE over the clinical risk spectrum in different populations. Serial CCTA studies have advanced our understanding of vascular biology and atherosclerotic disease progression. The direct disease visualization of CCTA has the potential to be used synergistically with indirect markers of risk to significantly improve prevention of MACE, pending large-scale randomized evaluation.

17.
Cureus ; 16(3): e56428, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38638720

RESUMEN

Penetrating aortic ulcer (PAU) is a component of acute aortic syndromes (AASs), encompassing a range of potentially life-threatening aortic conditions such as dissection, intramural hematoma (IMH), and PAU itself. Ruptured PAU constitutes an emergency requiring surgical intervention. Here, we present a case involving a 47-year-old male patient admitted to our emergency department due to severe abdominal pain, malaise, and tenderness of the abdominal wall, which commenced abruptly several hours prior. An emergency CT scan revealed a large pseudoaneurysm of the infrarenal abdominal aorta, which was found with moderate atherosclerosis and no evidence of other dilated or aneurysmal segments. The patient underwent successful endovascular treatment and was discharged four days later without complications. Follow-up examination after two months demonstrated a patent graft and reduction of the aneurysmal sac.

18.
Front Immunol ; 15: 1383110, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650930

RESUMEN

Exhausted CD8 T cells (TEX) are associated with worse outcome in cancer yet better outcome in autoimmunity. Building on our past findings of increased TIGIT+KLRG1+ TEX with teplizumab therapy in type 1 diabetes (T1D), in the absence of treatment we found that the frequency of TIGIT+KLRG1+ TEX is stable within an individual but differs across individuals in both T1D and healthy control (HC) cohorts. This TIGIT+KLRG1+ CD8 TEX population shares an exhaustion-associated EOMES gene signature in HC, T1D, rheumatoid arthritis (RA), and cancer subjects, expresses multiple inhibitory receptors, and is hyporesponsive in vitro, together suggesting co-expression of TIGIT and KLRG1 may broadly define human peripheral exhausted cells. In HC and RA subjects, lower levels of EOMES transcriptional modules and frequency of TIGIT+KLRG1+ TEX were associated with RA HLA risk alleles (DR0401, 0404, 0405, 0408, 1001) even when considering disease status and cytomegalovirus (CMV) seropositivity. Moreover, the frequency of TIGIT+KLRG1+ TEX was significantly increased in RA HLA risk but not non-risk subjects treated with abatacept (CTLA4Ig). The DR4 association and selective modulation with abatacept suggests that therapeutic modulation of TEX may be more effective in DR4 subjects and TEX may be indirectly influenced by cellular interactions that are blocked by abatacept.


Asunto(s)
Abatacept , Alelos , Artritis Reumatoide , Linfocitos T CD8-positivos , Receptores Inmunológicos , Humanos , Abatacept/uso terapéutico , Abatacept/farmacología , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/inmunología , Artritis Reumatoide/genética , Masculino , Femenino , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/efectos de los fármacos , Adulto , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Antígenos HLA/genética , Antígenos HLA/inmunología , Persona de Mediana Edad , Antirreumáticos/uso terapéutico , Predisposición Genética a la Enfermedad , Agotamiento de Células T
19.
J Am Chem Soc ; 146(15): 10240-10245, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38578222

RESUMEN

Cellular compartments formed by biomolecular condensation are widespread features of cell biology. These organelle-like assemblies compartmentalize macromolecules dynamically within the crowded intracellular environment. However, the intermolecular interactions that produce condensed droplets may also create arrested states and potentially pathological assemblies such as fibers, aggregates, and gels through droplet maturation. Protein liquid-liquid phase separation is a metastable process, so maturation may be an intrinsic property of phase-separating proteins, where nucleation of different phases or states arises in supersaturated condensates. Here, we describe the formation of both phase-separated droplets and proteinaceous fibers driven by a de novo designed polypeptide. We characterize the formation of supramolecular fibers in vitro and in bacterial cells. We show that client proteins can be targeted to the fibers in cells using a droplet-forming construct. Finally, we explore the interplay between phase separation and fiber formation of the de novo polypeptide, showing that the droplets mature with a post-translational switch to largely ß conformations, analogous to models of pathological phase separation.


Asunto(s)
Fenómenos Bioquímicos , Proteínas , Humanos , Proteínas/química , Péptidos/metabolismo , Procesamiento Proteico-Postraduccional , Conformación Molecular
20.
bioRxiv ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38585999

RESUMEN

Cell size and biosynthetic capacity generally increase with increased DNA content. Polyploidy has therefore been proposed to be an adaptive strategy to increase cell size in specialized tissues with high biosynthetic demands. However, if and how DNA concentration limits cellular biosynthesis in vivo is not well understood, and the impacts of polyploidy in non-disease states is not well studied. Here, we show that polyploidy in the C. elegans intestine is critical for cell growth and yolk biosynthesis, a central role of this organ. Artificially lowering the DNA/cytoplasm ratio by reducing polyploidization in the intestine gave rise to smaller cells with more dilute mRNA. Highly-expressed transcripts were more sensitive to this mRNA dilution, whereas lowly-expressed genes were partially compensated - in part by loading more RNA Polymerase II on the remaining genomes. DNA-dilute cells had normal total protein concentration, which we propose is achieved by increasing production of translational machinery at the expense of specialized, cell-type specific proteins.

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