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1.
EJNMMI Phys ; 11(1): 59, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38977509

RESUMEN

BACKGROUND: Good timing resolution in medical imaging applications such as TOF-CT or TOF-PET can boost image quality or patient comfort significantly by reducing the influence of background noise. However, the timing resolution of state-of-the-art detectors in CT and PET are limited by their light emission process. Core-valence cross-luminescence is an alternative, but well-known compounds (e.g. BaF2) pose several problems for medical imaging applications, such as their emission wavelength in the deep UV. CsZnCl-based materials show promise to solve this issue, as they provide fast decay times of 1-2 ns and an emission wavelength around 300 nm. RESULTS: In this work, we investigated two CsZnCl-compounds: Cs2ZnCl4 and Cs3ZnCl5. We validated the previously published decay times on a time-correlated single-photon counting setup with 1.786 ± 0.016 ns for Cs2ZnCl4 and 1.034 ± 0.013 ns for Cs3ZnCl5. The setup's high resolution enabled the discovery of an additional prompt emission component with a significant abundance of 98 ± 18 (Cs2ZnCl4) and 86 ± 14 (Cs3ZnCl5) photons/MeV energy deposit. In a PET coincidence experiment, we measured the best coincidence time resolution (CTR) of 62 ps (FWHM) for Cs2ZnCL4 coupled to FBK VUV SiPMs with silicon oil. To assess the CTR for lower energies, we filtered the energy along the Compton continuum and found a deteriorated CTR that seems to be mainly influenced by photon statistics. Furthermore, this study gave us a rough estimate of e.g. 150 ps (FWHM) CTR at 100 keV energy for Cs2ZnCL4. From measurements with high activity of 14 MBq to check for pile-up effects we assume that Cs2ZnCl4 is better suited for high-rate time-of-flight applications than lutetium-based oxides. Simulations demonstrated that the stopping power of Cs2ZnCl4 is lower than for LSO:Ce,Ca, meaning that a high amount of material would be needed for TOF-PET applications. However, the stopping power seems acceptable for applications in TOF-CT. CONCLUSIONS: The fast decay time, state-of-the-art CTR in benchtop experiments and high-rate suitability make CsZnCl materials a promising candidate for time-of-flight experiments. We consider especially TOF-CT a suitable application due to its relatively low X-ray energies (~ 100 keV) and the thusly acceptable stopping power of Cs2ZnCl4. Currently, further exploration of the prompt emission and its creation mechanism is planned, as well as investigating the light transport of Cs2ZnCl4 in longer crystals.

2.
ERJ Open Res ; 10(4)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38978544

RESUMEN

Rationale: Nontuberculous mycobacteria (NTM) has been reported to be transmitted between people with cystic fibrosis (CF) attending CF centres. A suspected Mycobacterium abscessus outbreak was investigated at the University of Texas Southwestern (UTSW) Adult CF Program using a combination of pathogen genomic sequencing and epidemiologic methods. The objectives of the present study were to apply the Healthcare-Associated Links in Transmission of NTM (HALT NTM) study to investigate the occurrence of potential healthcare-associated transmission and/or acquisition of NTM among people with CF infected with genetically similar NTM isolates. Methods: Whole-genome sequencing of respiratory M. abscessus isolates from 50 people with CF receiving care at UTSW was performed to identify genetically similar isolates. Epidemiologic investigation, comparison of respiratory and environmental isolates, and home residence watershed mapping were studied. Measurements and main results: Whole-genome sequencing analysis demonstrated seven clusters of genetically similar M. abscessus (four ssp. abscessus and three ssp. massiliense). Epidemiologic investigation revealed potential opportunities for healthcare-associated transmission within three of these clusters. Healthcare environmental sampling did not recover M. abscessus, but did recover four human disease-causing species of NTM. No subjects having clustered infections lived in the same home residence watershed. Some subjects were infected with more than one M. abscessus genotype, both within and outside of the dominant circulating clones. Conclusions: Healthcare-associated person-to-person transmission of M. abscessus appears to be rare at this centre. However, polyclonal infections of M. abscessus species and subspecies, not originating from the endemic hospital environment, suggest multiple shared modes of acquisition outside the healthcare setting.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39018574

RESUMEN

Venous thromboembolism (VTE), comprising pulmonary embolism and deep vein thrombosis, is one of the most common complications after knee arthroscopy. Sequelae of VTE include VTE recurrence, postthrombotic syndrome, and potential for loss of limb or life. Given the increasing volume of knee arthroscopy procedures worldwide and the considerable morbidity and mortality associated with VTE, it is important to prevent, diagnose, and treat VTEs efficiently and effectively. Risk factors such as history of VTE, family history of VTE, genetic coagulopathy, oral contraceptive use, cancer history, and old age increase the risk of postoperative VTE and warrant consideration of prophylaxis. Diagnosis and treatment should be initiated rapidly in the setting of concerning symptoms and positive imaging diagnosis, respectively. The purpose of this review was to provide a framework to individualized VTE risk, weigh prophylaxis options, expedite diagnostic pathways, and implement outpatient treatment algorithms.

4.
Nature ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020167

RESUMEN

A single dose of psilocybin, a psychedelic that acutely causes distortions of space-time perception and ego dissolution, produces rapid and persistent therapeutic effects in human clinical trials1-4. In animal models, psilocybin induces neuroplasticity in cortex and hippocampus5-8. It remains unclear how human brain network changes relate to subjective and lasting effects of psychedelics. Here we tracked individual-specific brain changes with longitudinal precision functional mapping (roughly 18 magnetic resonance imaging visits per participant). Healthy adults were tracked before, during and for 3 weeks after high-dose psilocybin (25 mg) and methylphenidate (40 mg), and brought back for an additional psilocybin dose 6-12 months later. Psilocybin massively disrupted functional connectivity (FC) in cortex and subcortex, acutely causing more than threefold greater change than methylphenidate. These FC changes were driven by brain desynchronization across spatial scales (areal, global), which dissolved network distinctions by reducing correlations within and anticorrelations between networks. Psilocybin-driven FC changes were strongest in the default mode network, which is connected to the anterior hippocampus and is thought to create our sense of space, time and self. Individual differences in FC changes were strongly linked to the subjective psychedelic experience. Performing a perceptual task reduced psilocybin-driven FC changes. Psilocybin caused persistent decrease in FC between the anterior hippocampus and default mode network, lasting for weeks. Persistent reduction of hippocampal-default mode network connectivity may represent a neuroanatomical and mechanistic correlate of the proplasticity and therapeutic effects of psychedelics.

5.
J Neurosurg ; : 1-6, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996401

RESUMEN

OBJECTIVE: The paucity of literature comparing Woven EndoBridge (WEB) embolization to microsurgical clipping for anterior circulation wide-neck bifurcation aneurysms (WNBAs) underscores the need for further investigation into the optimal management of this patient subpopulation. The objective of this study was to compare the rate of endovascular and microsurgical treatment of WNBAs before and after the introduction of the WEB device. In addition, the authors performed a comparison of demographics, aneurysm characteristics, and treatment outcomes in patients before and after the introduction of the WEB device. METHODS: This study was a retrospective review of the usage rate of different treatment modalities for WNBAs before and after the WEB device was approved by the US FDA on September 27, 2018. RESULTS: The study cohort comprised 235 patients with anterior circulation WNBAs treated at the authors' institution, including 127 aneurysms treated pre-WEB and 108 treated post-WEB. Generally, the rate of endovascular treatment of anterior circulation WNBAs was significantly higher post-WEB (86.1% vs 46.5%, p < 0.001), while the rate of clipping was significantly lower (13.9% vs 53.5%, p < 0.001). During follow-up, the rate of adequate aneurysm occlusion (Raymond-Roy occlusion classification [RROC] grades 1 and 2) was nonsignificantly higher in the post-WEB cohort (83.9% vs 78.5%, p = 0.34), while the rate of RROC grade 3 was nonsignificantly higher in the pre-WEB cohort (21.5% vs 16.1%, p = 0.34). Additionally, and although nonsignificant, the rates of recurrence (pre-WEB 25.3% vs post-WEB 14.9%, p = 0.12) and retreatment (pre-WEB 22.8% vs post-WEB 14.9%, p = 0.22) were higher in the pre-WEB cohort. Recurrence was assessed before retreatment. CONCLUSIONS: After the introduction of the WEB device, the rate of endovascular treatment of WNBAs increased while the rate of microsurgical clipping decreased. It is essential for neurointerventionalists to become familiar with the indications, advantages, and shortcomings of all these different techniques to be able to match the right patient with the right technique to produce the best outcome.

6.
Sci Rep ; 14(1): 15803, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982100

RESUMEN

We report the photon (PL), electron (CL) and X-ray (XEL) induced luminescence characteristics of high aspect ratio ultra-long (~ 50 µm) ZnO nanorods (NRs) and discuss the potential for fast X-ray detection based on the consistent and efficient visible emission (~ 580 nm) from ZnO NRs. Nanostructured ZnO scintillators were rearranged to form a vertically well-aligned NR design in order to help light absorption and coupling resulting in luminescent and fast scintillation properties. The design of the nanorod array combines the key advantages of a low-cost growth technique together with environmentally friendly and widely available materials. A low temperature hydrothermal method was adopted to grow ZnO NRs in one cycle growth and their structural, optical and X-ray scintillation properties were investigated. The relatively short (~ 10 µm) ZnO NRs emitting in the near-band-edge region were found to be almost insensitive to X-rays. On the other hand, the higher XEL response of long ZnO NRs, which is a key parameter for evaluation of materials to be used as scintillators for high quality X-ray detection and imaging, along with a decay time response in the order of ns confirmed promising scintillation properties for fast and high-resolution X-ray detector applications.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38976133

RESUMEN

PURPOSE: To evaluate the association, if any, between the grade of the trophectoderm (TE) and the rate at which ß-human-chorionic gonadotropin (ß-HCG) rises in early pregnancy. METHODS: This is a retrospective cohort study including 1116 singleton clinical pregnancies resulting from in vitro fertilization with single day 5 blastocyst transfer at an academic fertility center. TE quality was assessed by trained embryologists employing standard criteria. Three groups were formed based on the TE grade: grade A (n = 358), grade B (n = 628), and grade C (n = 130). Main outcome measure was the rise (%) in serum levels of ß-HCG (days 12 to 14 post embryo transfer), using the following formula [(ß-HCG D14 - ß-HCG D12) * 100/ß-HCG D12]. RESULTS: Fresh embryo transfers accounted for 64.1% of the population. Overall, in adjusted models there were no significant differences in the ß-HCG% rise when comparing the TE grade C group to TE grade A [adjß (95%CI): 10.09 (- 0.05, 20.22)] or when comparing TE grade Β group to TE grade A [4.46 (- 2.97, 11.88)]. When the analysis was restricted to fresh embryo transfers, significant differences were observed in the % rise of ß-HCG when comparing the TE grade C group to TE grade A [adjß (95%CI): 21.71 (5.67, 37.74)], but not when comparing the TE grade B group to TE grade A [2.68 (- 5.59, 10.95)]. In frozen transfers, there were no significant differences. CONCLUSION: TE grade appears to impact early pregnancy serum ß-HCG levels in the setting of a fresh day 5 embryo transfer, even after adjusting for potential confounders.

8.
Cell Death Dis ; 15(7): 513, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025852

RESUMEN

Metabolic reprogramming and energetic rewiring are hallmarks of cancer that fuel disease progression and facilitate therapy evasion. The remodelling of oxidative phosphorylation and enhanced lipogenesis have previously been characterised as key metabolic features of prostate cancer (PCa). Recently, succinate-dependent mitochondrial reprogramming was identified in high-grade prostate tumours, as well as upregulation of the enzymes associated with branched-chain amino acid (BCAA) catabolism. In this study, we hypothesised that the degradation of the BCAAs, particularly valine, may play a critical role in anapleurotic refuelling of the mitochondrial succinate pool, as well as the maintenance of intracellular lipid metabolism. Through the suppression of BCAA availability, we report significantly reduced lipid content, strongly indicating that BCAAs are important lipogenic fuels in PCa. This work also uncovered a novel compensatory mechanism, whereby fatty acid uptake is increased in response to extracellular valine deprivation. Inhibition of valine degradation via suppression of 3-hydroxyisobutyryl-CoA hydrolase (HIBCH) resulted in a selective reduction of malignant prostate cell proliferation, decreased intracellular succinate and impaired cellular respiration. In combination with a comprehensive multi-omic investigation that incorporates next-generation sequencing, metabolomics, and high-content quantitative single-cell imaging, our work highlights a novel therapeutic target for selective inhibition of metabolic reprogramming in PCa.


Asunto(s)
Neoplasias de la Próstata , Valina , Masculino , Humanos , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/genética , Valina/farmacología , Valina/metabolismo , Línea Celular Tumoral , Proliferación Celular , Mitocondrias/metabolismo , Aminoácidos de Cadena Ramificada/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Ácido Succínico/metabolismo , Reprogramación Metabólica
9.
J Chem Theory Comput ; 20(14): 6098-6110, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38976796

RESUMEN

Alchemical free energy methods are useful in computer-aided drug design and computational protein design because they provide rigorous statistical mechanics-based estimates of free energy differences from molecular dynamics simulations. λ dynamics is a free energy method with the ability to characterize combinatorial chemical spaces spanning thousands of related systems within a single simulation, which gives it a distinct advantage over other alchemical free energy methods that are mostly limited to pairwise comparisons. Recently developed methods have improved the scalability of λ dynamics to perturbations at many sites; however, the size of chemical space that can be explored at each individual site has previously been limited to fewer than ten substituents. As the number of substituents increases, the volume of alchemical space corresponding to nonphysical alchemical intermediates grows exponentially relative to the size corresponding to the physical states of interest. Beyond nine substituents, λ dynamics simulations become lost in an alchemical morass of intermediate states. In this work, we introduce new biasing potentials that circumvent excessive sampling of intermediate states by favoring sampling of physical end points relative to alchemical intermediates. Additionally, we present a more scalable adaptive landscape flattening algorithm for these larger alchemical spaces. Finally, we show that this potential enables more efficient sampling in both protein and drug design test systems with up to 24 substituents per site, enabling, for the first time, simultaneous simulation of all 20 amino acids.


Asunto(s)
Simulación de Dinámica Molecular , Proteínas/química , Termodinámica , Algoritmos , Diseño de Fármacos
10.
Proc Natl Acad Sci U S A ; 121(28): e2322203121, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38968122

RESUMEN

Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)-a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single-cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to current and future antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.


Asunto(s)
Análisis de la Célula Individual , Masculino , Humanos , Análisis de la Célula Individual/métodos , Animales , Ratones , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/tratamiento farmacológico , Antígenos de Superficie/metabolismo , Antígenos de Superficie/genética , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Adenocarcinoma/genética , Adenocarcinoma/patología , Adenocarcinoma/metabolismo , Adenocarcinoma/tratamiento farmacológico , Carcinoma Neuroendocrino/genética , Carcinoma Neuroendocrino/patología , Carcinoma Neuroendocrino/metabolismo , Carcinoma Neuroendocrino/tratamiento farmacológico , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico
11.
ERJ Open Res ; 10(4)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39040578

RESUMEN

Introduction: Brensocatib is an investigational, oral, reversible inhibitor of dipeptidyl peptidase-1 shown to prolong time to first exacerbation in adults with bronchiectasis. Outlined here are the clinical trial design, and baseline characteristics and treatment patterns of adult patients enrolled in the phase 3 ASPEN trial (NCT04594369). Methods: The ASPEN trial is a global study enrolling patients with a clinical history consistent with bronchiectasis (cough, chronic sputum production and/or recurrent respiratory infections), diagnosis confirmed radiologically and ≥2 exacerbations in the prior 12 months. It was designed to evaluate the impact of two brensocatib doses (10 mg and 25 mg) on exacerbation rate over a 52-week treatment period versus placebo. Comprehensive clinical data, including demographics, disease severity, lung function, Pseudomonas aeruginosa status and quality of life, were collected at baseline. Results: 1682 adults from 35 countries were randomised from December 2020 to March 2023. Mean age was 61.3 years and 64.7% were female. ∼70% had moderate-to-severe Bronchiectasis Severity Index (BSI) scores, 29.3% had ≥3 exacerbations in the prior 12 months and 35.7% were positive for P. aeruginosa. Mean BSI scores were highest in Australia/New Zealand (8.3) and lowest in Latin America (5.9). Overall, the most common aetiology was idiopathic (58.4%). In P. aeruginosa-positive versus P. aeruginosa-negative patients, lung function was lower, with greater long-term macrolide (21.5% versus 14.0%) and inhaled corticosteroid use (63.5% versus 53.9%). There was wide regional variation in long-term antibiotic use in patients with bronchiectasis and P. aeruginosa. Discussion: ASPEN baseline characteristics and treatment profiles were representative of a global bronchiectasis population.

12.
Pharmacol Res Perspect ; 12(4): e1217, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38923845

RESUMEN

It is a paradox that psychotomimetic drugs can relieve symptoms that increase risk of and cooccur with psychosis, such as attention and motivational deficits (e.g., amphetamines), pain (e.g., cannabis) and symptoms of depression (e.g., psychedelics, dissociatives). We introduce the ideas of psychotomimetic compensation and psychotomimetic sensitization to explain this paradox. Psychotomimetic compensation refers to a short-term stressor or drug-induced compensation against stress that is facilitated by engagement of neurotransmitter/modulator systems (endocannabinoid, serotonergic, glutamatergic and dopaminergic) that mediate the effects of common psychotomimetic drugs. Psychotomimetic sensitization occurs after repeated exposure to stress and/or drugs and is evidenced by the gradual intensification and increase of psychotic-like experiences over time. Theoretical and practical implications of this model are discussed.


Asunto(s)
Alucinógenos , Humanos , Alucinógenos/farmacología , Animales , Estrés Psicológico/psicología , Psicosis Inducidas por Sustancias/etiología , Neurotransmisores/metabolismo
13.
J Am Chem Soc ; 146(26): 17669-17678, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38905328

RESUMEN

The genus Mycobacterium includes species such as Mycobacterium tuberculosis, which can cause deadly human diseases. These bacteria have a protective cell envelope that can be remodeled to facilitate their survival in challenging conditions. Understanding how such conditions affect membrane remodeling can facilitate antibiotic discovery and treatment. To this end, we describe an optimized fluorogenic probe, N-QTF, that reports on mycolyltransferase activity, which is vital for cell division and remodeling. N-QTF is a glycolipid probe that can reveal dynamic changes in the mycobacterial cell envelope in both fast- and slow-growing mycobacterial species. Using this probe to monitor the consequences of antibiotic treatment uncovered distinct cellular phenotypes. Even antibiotics that do not directly inhibit cell envelope biosynthesis cause conspicuous phenotypes. For instance, mycobacteria exposed to the RNA polymerase inhibitor rifampicin release fluorescent extracellular vesicles (EVs). While all mycobacteria release EVs, fluorescent EVs were detected only in the presence of RIF, indicating that exposure to the drug alters EV content. Macrophages exposed to the EVs derived from RIF-treated cells released lower levels of cytokines, suggesting the EVs moderate immune responses. These data suggest that antibiotics can alter EV content to impact immunity. Our ability to see such changes in EV constituents directly results from exploiting these chemical probes.


Asunto(s)
Colorantes Fluorescentes , Mycobacterium tuberculosis , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Mycobacterium tuberculosis/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Vesículas Extracelulares/química , Vesículas Extracelulares/metabolismo , Humanos
14.
J Alzheimers Dis ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943393

RESUMEN

The Montreal Cognitive Assessment (MoCA) is a valuable assessment of the patient's awareness of time and place. We show that bacille Calmette-Guerin (BCG) significantly affects MoCA testing when administered by the intravesical route. MoCA scores were lower with increasing age and higher in more formally educated individuals. Patients receiving BCG tended to maintain their MoCA scores, whereas almost half the control cases tended to show reduced scores. This benefit is supported by reduced pre-amyloid biomarkers in BCG-injected healthy volunteers and a favorable effect on neuronal dendritic development in animal models. Our results suggest that BCG has a beneficial impact on the cognitive status of older individuals.

15.
J Appl Physiol (1985) ; 137(1): 111-124, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38841755

RESUMEN

Electrically evoked contractions are used to assess the relationship between frequency input and contractile output to characterize inherent muscle function, and these have been done mostly with isometric contractions (i.e., no joint rotation). The purpose was to compare the electrically stimulated frequency and contractile function relationship during isometric (i.e., torque) with isotonic (i.e., concentric torque, angular velocity, and mechanical power) contractions. The knee extensors of 16 (5 female) young recreationally active participants were stimulated (∼1-2.5 s) at 14 frequencies from 1 to 100 Hz. This was done during four conditions, which were isometric and isotonic at loads of 0 (unloaded), 7.5%, and 15% isometric maximal voluntary contraction (MVC), and repeated on separate days. Comparisons across contractile parameters were made as a % of 100 Hz. Independent of the load, the mechanical power-frequency relationship was rightward shifted compared with isometric torque-frequency, concentric torque-frequency, and velocity-frequency relationships (all P ≤ 0.04). With increasing load (0%-15% MVC), the isotonic concentric torque-frequency relationship was shifted leftward systematically from 15 to 30 Hz (all P ≤ 0.04). Conversely, the same changes in load caused a rightward shift in the velocity-frequency relationship from 1 to 40 Hz (all P ≤ 0.03). Velocity was leftward shifted of concentric torque in the unloaded isotonic condition from 10 to 25 Hz (all P ≤ 0.03), but concentric torque was leftward shifted of velocity at 15% MVC isotonic condition from 10 to 50 Hz (all P ≤ 0.03). Therefore, isometric torque is not a surrogate to evaluate dynamic contractile function. Interpretations of evoked contractile function differ depending on contraction type, load, and frequency, which should be considered relative to the specific task.NEW & NOTEWORTHY In whole human muscle, we showed that the electrically stimulated power-frequency relationship was rightward shifted of the stimulated isometric torque-frequency relationship independent of isotonic load, indicating that higher stimulation frequencies are needed to achieve tetanus. Therefore, interpretations of evoked contractile function differ depending on contraction type (isometric vs. dynamic), load, and frequency. And thus, isometric measures may not be appropriate as a surrogate assessment when evaluating dynamic isotonic contractile function.


Asunto(s)
Estimulación Eléctrica , Contracción Isométrica , Contracción Isotónica , Músculo Cuádriceps , Torque , Humanos , Femenino , Contracción Isométrica/fisiología , Masculino , Contracción Isotónica/fisiología , Músculo Cuádriceps/fisiología , Estimulación Eléctrica/métodos , Adulto , Adulto Joven , Rodilla/fisiología , Contracción Muscular/fisiología
16.
Clin Case Rep ; 12(6): e9082, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38883227

RESUMEN

We report a patient with nonimmune fetal hydrops and multiple pathologic fractures. RNA analysis revealed a novel PIEZO1 variant. This report is the first to elucidate PIEZO1's role as a critical regulator of bone mass and strength.

17.
J Thorac Dis ; 16(5): 3366-3370, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38883635

RESUMEN

Mycobacterium gordonae (M. gordonae) is a species of nontuberculous mycobacteria (NTM) that rarely causes infection. It has previously been labeled the most common NTM contaminant. Bronchiectasis is a disease characterized by abnormal airway dilation leading to chronic cough, sputum production and pulmonary infections. Patients with bronchiectasis are at higher risk of NTM-lung disease with more pathogenic NTM species including Mycobacterium avium complex (MAC) and Mycobacterium abscessus (M. abscessus). The relationship between bronchiectasis and less-pathogenic NTM species such as M. gordonae is less well understood. We performed a retrospective study on patients who had M. gordonae isolated from respiratory specimens at UConn Health between May 2nd, 2010 and October 18th, 2022. M. gordonae was isolated 74 times from 56 patients. It was isolated 35 (47.3%) times from 31 patients with bronchiectasis and 39 (52.7%) times from 26 patients without bronchiectasis. Data was available on all mycobacterial cultures sent from May 2nd 2018 to October 18th 2022. Mycobacterial cultures sent from patients with bronchiectasis were significantly more likely to grow M. gordonae than patients without bronchiectasis (4.3% vs. 1.6%, P=0.007). Furthermore, when considered at the patient level, there remained a significant increased rate of M. gordonae isolation among patients with bronchiectasis (7.1% vs. 2.2%, P<0.001). We then looked at past and future isolation of more pathogenic NTM species and found a non-statistically increased rate of isolation of more pathogenic NTM species including MAC and M. abscessus in patients with bronchiectasis (45.2% vs. 29%, P=0.09). Based on our results, isolation of M. gordonae should raise suspicion of chronic airway disease and defects in host immune response, such as those seen in bronchiectasis. Furthermore, isolation of M. gordonae may suggest increased risk of infection with more pathogenic NTM species such as MAC and M. abscessus.

18.
JAMA Netw Open ; 7(6): e2414582, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38833252

RESUMEN

Importance: Prostate-specific antigen (PSA) screening for prostate cancer is controversial but may be associated with benefit for certain high-risk groups. Objectives: To evaluate associations of county-level PSA screening prevalence with prostate cancer outcomes, as well as variation by sociodemographic and clinical factors. Design, Setting, and Participants: This cohort study used data from cancer registries based in 8 US states on Hispanic, non-Hispanic Black, and non-Hispanic White men aged 40 to 99 years who received a diagnosis of prostate cancer between January 1, 2000, and December 31, 2015. Participants were followed up until death or censored after 10 years or December 31, 2018, whichever end point came first. Data were analyzed between September 2023 and January 2024. Exposure: County-level PSA screening prevalence was estimated using the Behavior Risk Factor Surveillance System survey data from 2004, 2006, 2008, 2010, and 2012 and weighted by population characteristics. Main Outcomes and Measures: Multivariable logistic, Cox proportional hazards regression, and competing risks models were fit to estimate adjusted odds ratios (AOR) and adjusted hazard ratios (AHR) for associations of county-level PSA screening prevalence at diagnosis with advanced stage (regional or distant), as well as all-cause and prostate cancer-specific survival. Results: Of 814 987 men with prostate cancer, the mean (SD) age was 67.3 (9.8) years, 7.8% were Hispanic, 12.2% were non-Hispanic Black, and 80.0% were non-Hispanic White; 17.0% had advanced disease. There were 247 570 deaths over 5 716 703 person-years of follow-up. Men in the highest compared with lowest quintile of county-level PSA screening prevalence at diagnosis had lower odds of advanced vs localized stage (AOR, 0.86; 95% CI, 0.85-0.88), lower all-cause mortality (AHR, 0.86; 95% CI, 0.85-0.87), and lower prostate cancer-specific mortality (AHR, 0.83; 95% CI, 0.81-0.85). Inverse associations between PSA screening prevalence and advanced cancer were strongest among men of Hispanic ethnicity vs other ethnicities (AOR, 0.82; 95% CI, 0.78-0.87), older vs younger men (aged ≥70 years: AOR, 0.77; 95% CI, 0.75-0.79), and those in the Northeast vs other US Census regions (AOR, 0.81; 95% CI, 0.79-0.84). Inverse associations with all-cause mortality were strongest among men of Hispanic ethnicity vs other ethnicities (AHR, 0.82; 95% CI, 0.78-0.85), younger vs older men (AHR, 0.81; 95% CI, 0.77-0.85), those with advanced vs localized disease (AHR, 0.80; 95% CI, 0.78-0.82), and those in the West vs other US Census regions (AHR, 0.89; 95% CI, 0.87-0.90). Conclusions and Relevance: This population-based cohort study of men with prostate cancer suggests that higher county-level prevalence of PSA screening was associated with lower odds of advanced disease, all-cause mortality, and prostate cancer-specific mortality. Associations varied by age, race and ethnicity, and US Census region.


Asunto(s)
Detección Precoz del Cáncer , Antígeno Prostático Específico , Neoplasias de la Próstata , Humanos , Masculino , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/diagnóstico , Antígeno Prostático Específico/sangre , Anciano , Persona de Mediana Edad , Detección Precoz del Cáncer/estadística & datos numéricos , Detección Precoz del Cáncer/métodos , Estados Unidos/epidemiología , Anciano de 80 o más Años , Adulto , Estudios de Cohortes , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Hispánicos o Latinos/estadística & datos numéricos
19.
Nature ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862027

RESUMEN

The recent acceleration of commercial, private, and multi-national spaceflight has created an unprecedented level of activity in low Earth orbit (LEO), concomitant with the highest-ever number of crewed missions entering space and preparations for exploration-class (>1 year) missions. Such rapid advancement into space from many new companies, countries, and space-related entities has enabled a"Second Space Age." This new era is also poised to leverage, for the first time, modern tools and methods of molecular biology and precision medicine, thus enabling precision aerospace medicine for the crews. The applications of these biomedical technologies and algorithms are diverse, encompassing multi-omic, single-cell, and spatial biology tools to investigate human and microbial responses to spaceflight. Additionally, they extend to the development of new imaging techniques, real-time cognitive assessments, physiological monitoring, and personalized risk profiles tailored for astronauts. Furthermore, these technologies enable advancements in pharmacogenomics (PGx), as well as the identification of novel spaceflight biomarkers and the development of corresponding countermeasures. In this review, we highlight some of the recent biomedical research from the National Aeronautics and Space Administration (NASA), Japan Aerospace Exploration Agency (JAXA), European Space Agency (ESA), and other space agencies, and also detail the commercial spaceflight sector's (e.g. SpaceX, Blue Origin, Axiom, Sierra Space) entrance into aerospace medicine and space biology, the first aerospace medicine biobank, and the myriad upcoming missions that will utilize these tools to ensure a permanent human presence beyond LEO, venturing out to other planets and moons.

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