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1.
Skeletal Radiol ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240311

RESUMO

OBJECTIVE: To analyze and quantify the change in United States of America Medicare reimbursement rates for the 30 most commonly performed spinal imaging procedures. MATERIALS AND METHODS: The Physician Fee Schedule Look-Up Tool from the Centers for Medicare & Medicaid Services was utilized to find and extract the 28 most billed spinal imaging procedures. All data was adjusted for inflation and listed in 2020 US dollars. Percent change in reimbursement and Relative Value Units between 2005 and 2020, both unadjusted and adjusted, were calculated and compared. Additionally, percent change per year and compound annual growth rate were calculated and compared. RESULTS: After adjusting for inflation, the average reimbursement for all analyzed spinal imaging procedures between the years 2005 and 2020 decreased by 45.9%. The adjusted reimbursement rate for all procedures decreased at an average 4.3% per year and experienced an average compound annual growth rate (CAGR) of - 4.4%. Magnetic resonance imaging (MRI) had the most substantial adjusted decline of all imaging modalities at - 72.6%, whereas x-ray imaging had the smallest decline at - 27.33%. The average total RVUs per procedure decreased by 50.1%, from 7.96 to 3.97. CONCLUSION: From the years 2005 to 2020, Medicare reimbursement significantly decreased for all advanced imaging modalities involving the most common spinal imaging procedures. Among all practices, imaging procedures may be experiencing some of the largest decreases from Medicare reimbursement cutbacks.

2.
J Alzheimers Dis ; 101(1): 49-60, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39093068

RESUMO

Background: Recent advances linking gut dysbiosis with neurocognitive disorders such as Alzheimer's disease (AD) suggest that the microbiota-gut-brain axis could be targeted for AD prevention, management, or treatment. Objective: We sought to identify probiotics that can delay Aß-induced paralysis. Methods: Using C. elegans expressing human amyloid-ß (Aß)1-42 in body wall muscles (GMC101), we assessed the effects of several probiotic strains on paralysis. Results: We found that Lacticaseibacillus rhamnosus HA-114 and Bacillus subtilis R0179, but not their supernatants or heat-treated forms, delayed paralysis and prolonged lifespan without affecting the levels of amyloid-ß aggregates. To uncover the mechanism involved, we explored the role of two known pathways involved in neurogenerative diseases, namely mitophagy, via deletion of the mitophagy factor PINK-1, and fatty acid desaturation, via deletion of the Δ9 desaturase FAT-5. Pink-1 deletion in GMC101 worms did not modify the life-prolonging and anti-paralysis effects of HA-114 but reduced the protective effect of R0179 against paralysis without affecting its life-prolonging effect. Upon fat5 deletion in GMC101 worms, the monounsaturated C14:1 and C16:1 FAs conserved their beneficial effect while the saturated C14:0 and C16:0 FAs did not. The beneficial effects of R0179 on both lifespan and paralysis remained unaffected by fat-5 deletion, while the beneficial effect of HA-114 on paralysis and lifespan was significantly reduced. Conclusions: Collectively with clinical and preclinical evidence in other models, our results suggest that HA-114 or R0179 could be studied as potential therapeutical adjuncts in neurodegenerative diseases such as AD.


Assuntos
Peptídeos beta-Amiloides , Bacillus subtilis , Caenorhabditis elegans , Lacticaseibacillus rhamnosus , Longevidade , Probióticos , Animais , Longevidade/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/toxicidade , Paralisia , Fragmentos de Peptídeos/toxicidade , Fragmentos de Peptídeos/metabolismo , Animais Geneticamente Modificados , Humanos , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo
3.
Biomol NMR Assign ; 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39215796

RESUMO

The detection of nucleic acids that are present in atypical conformations is a crucial trigger of the innate immune response. Human Z-DNA binding protein 1 (ZBP1) is a pattern recognition receptor that harbors two Zα domains that recognize Z-DNA and Z-RNA. ZBP1 detects this alternate nucleic acid conformation as foreign, and upon stabilization of these substrates, it triggers activation of an immune response. Here, we present the backbone chemical shift assignment of a construct encompassing the Zα1 and Zα2 domains as well as the interconnecting linker of ZBP1. These assignments can be directly transferred to the isolated Zα1 and Zα2 domains, thereby demonstrating that these domains maintain virtually identical structures in the tandem context.

4.
F S Sci ; 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39074663

RESUMO

OBJECTIVE: To determine if engineered high-mobility group AT-hook 2 (HMGA2) overexpressing uterine primary myometrial cells recapitulate the transcriptional and epigenomic features of HMGA2-subtype leiomyomas. DESIGN: Isolated primary, "normal" myometrial cells from three patients were engineered to overexpress HMGA2 to determine how HMGA2 establishes transcriptomic and epigenomic features of HMGA2-overexpressing leiomyoma. SETTING: Academic research laboratory. PATIENT(S): Primary myometrial cells were isolated from normal myometrium obtained from three patients undergoing hysterectomy. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Determined genome-wide transcriptomic and epigenomic features of engineered HMGA2-overexpressing uterine primary myometrial cells. RESULT(S): Engineered HMGA2-V5-overexpressing primary myometrial cells approximated the HMGA2 expression level observed in HMGA2-overexpression subtype leiomyoma. High-mobility group AT-hook 2-V5 expression resulted in differential expression of 1,612 genes (false discovery rate [FDR] < 0.05) that were found to be enriched in pathways associated with leiomyoma formation, including extracellular matrix organization. Comparative gene expression analysis between HMGA2-V5 engineered primary cells and HMGA2-overexpression subtype leiomyoma revealed significant overlap of differentially expressed genes. Mechanistically, HMGA2-V5 overexpression resulted in 41,323 regions with differential H3K27ac deposition (FDR < 0.05) and 205,605 regions of altered chromatin accessibility (FDR < 0.05). Transcription factor binding site analysis implicated the AP-1 family of transcription factors. CONCLUSION(S): High-mobility group AT-hook 2 overexpression induces leiomyoma-like transcriptomic and epigenomic modulations in myometrial cells.

5.
JCI Insight ; 9(13)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38973611

RESUMO

Optimization of protective immune responses against SARS-CoV-2 remains an urgent worldwide priority. In this regard, type III IFN (IFN-λ) restricts SARS-CoV-2 infection in vitro, and treatment with IFN-λ limits infection, inflammation, and pathogenesis in murine models. Furthermore, IFN-λ has been developed for clinical use to limit COVID-19 severity. However, whether endogenous IFN-λ signaling has an effect on SARS-CoV-2 antiviral immunity and long-term immune protection in vivo is unknown. In this study, we identified a requirement for IFN-λ signaling in promoting viral clearance and protective immune programming in SARS-CoV-2 infection of mice. Expression of both IFN and IFN-stimulated gene (ISG) in the lungs were minimally affected by the absence of IFN-λ signaling and correlated with transient increases in viral titers. We found that IFN-λ supported the generation of protective CD8 T cell responses against SARS-CoV-2 by facilitating accumulation of CD103+ DC in lung draining lymph nodes (dLN). IFN-λ signaling specifically in DCs promoted the upregulation of costimulatory molecules and the proliferation of CD8 T cells. Intriguingly, antigen-specific CD8 T cell immunity to SARS-CoV-2 was independent of type I IFN signaling, revealing a nonredundant function of IFN-λ. Overall, these studies demonstrate a critical role for IFN-λ in protective innate and adaptive immunity upon infection with SARS-CoV-2 and suggest that IFN-λ serves as an immune adjuvant to support CD8 T cell immunity.


Assuntos
Linfócitos T CD8-Positivos , COVID-19 , Interferon Tipo I , SARS-CoV-2 , Animais , Linfócitos T CD8-Positivos/imunologia , SARS-CoV-2/imunologia , Camundongos , COVID-19/imunologia , COVID-19/virologia , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Pulmão/imunologia , Pulmão/virologia , Transdução de Sinais/imunologia , Modelos Animais de Doenças , Interferon lambda , Interferons/imunologia , Interferons/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Dendríticas/imunologia , Humanos
6.
medRxiv ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38978669

RESUMO

Background: Freezing of gait (FOG) is a debilitating symptom of Parkinson's disease (PD) that is often refractory to medication. Pathological prolonged beta bursts within the subthalamic nucleus (STN) are associated with both worse impairment and freezing behavior in PD, which are improved with deep brain stimulation (DBS). The goal of the current study was to investigate the feasibility, safety, and tolerability of beta burst-driven adaptive DBS (aDBS) for FOG in PD. Methods: Seven individuals with PD were implanted with the investigational Summit™ RC+S DBS system (Medtronic, PLC) with leads placed bilaterally in the STN. A PC-in-the-loop architecture was used to adjust stimulation amplitude in real-time based on the observed beta burst durations in the STN. Participants performed either a harnessed stepping-in-place task or a free walking turning and barrier course, as well as clinical motor assessments and instrumented measures of bradykinesia, OFF stimulation, on aDBS, continuous DBS (cDBS), or random intermittent DBS (iDBS). Results: Beta burst driven aDBS was successfully implemented and deemed safe and tolerable in all seven participants. Gait metrics such as overall percent time freezing and mean peak shank angular velocity improved from OFF to aDBS and showed similar efficacy as cDBS. Similar improvements were also seen for overall clinical motor impairment, including tremor, as well as quantitative metrics of bradykinesia. Conclusion: Beta burst driven adaptive DBS was feasible, safe, and tolerable in individuals with PD with gait impairment and FOG.

7.
Saudi J Ophthalmol ; 38(2): 144-151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988792

RESUMO

A scoping review of 45 peer-reviewed manuscripts involving intraocular pressure (IOP) change and concurrent optical coherence tomography angiography (OCTA) assessments was performed to aggregate knowledge, summarize major findings, and identify gaps in literature and methodology relating to the effect of IOP change on OCTA. Articles were identified through PubMed/Medline, Google Scholar, Cochrane, Web of Science, and article reference lists. A total of 838 results were identified, and 45 articles met the inclusion and exclusion criteria for detailed analysis. OCTA metrics including vessel density (VD), perfusion density, and flow density of the superficial capillary plexus and the radial peripapillary capillaries were analyzed in relation to relative temporal IOP changes. Overall, IOP changes were found to affect superficial vascular plexus (VD) measurements on OCTA, especially when IOP elevated above the physiologic normal range (10-21 mmHg). No significant association was found between diurnal IOP variation and OCTA metrics. Cataract surgery improved the whole-image signal strength and VD regardless of changes in IOP. Beta-blockers were associated with paradoxically reduced vessel density in normal tension glaucoma patients in two studies. Although glaucoma surgical intervention studies were inconsistent and limited by scan quality and low sample sizes, patients requiring glaucoma surgery exhibited attenuated postoperative superficial VD recovery despite significant IOP reductions with surgical intervention. In addition to ensuring near-perfect signal strength with minimal media opacities and controlling for high myopia, central corneal thickness, and the presence of retinopathy, clinicians should consider the statistically significant impact of IOP on OCTA metrics when interpreting results.

8.
R Soc Open Sci ; 11(5): 231165, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39076790

RESUMO

Insecticide-treated nets (ITNs) are the most effective method for malaria prevention in Africa. Using near-infrared video tracking in a laboratory environment, we recorded and assessed bednet entry and exit by a northern Tanzanian population of Anopheles arabiensis at a human-occupied untreated net and a PermaNet® 2.0 ITN. Both had 12 holes, each 10 cm in diameter, punctured at specific locations, and the ITN was washed 20 times to further simulate the wear and tear of ageing. Washing reduced the insecticide content of ITNs by 61%, which then showed similar rates to the untreated nets for net entry (39% entered untreated net and 41% entered ITN; p = 0.84) and exit (37% and 43%, respectively; p = 0.67). Regardless of treatment, approximately 40% of mosquitoes entered nets within 20 s of first appearing in the field of view and reached the volunteer's skin within 5 s of entering the net. Mortality rates post-exposure were significantly higher (p = 0.048) at ITNs (26.6%; 95% CI 13.4%-39.7%) than at untreated controls (6.4%; 95% CI 1.8%-14.6%). The washed and aged ITN provided little additional personal protection for the sleeper over an untreated net. Simple adjustments to materials and design that could extend the effective lifespan of ITNs are discussed.

9.
Anat Sci Educ ; 17(6): 1239-1250, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38825716

RESUMO

Supplemental instruction (SI) confers student success, as represented by grades, knowledge retention, and student engagement. However, studies often report professional, not undergraduate, program findings. To measure these effects, students studying human anatomy at a university in Ontario, Canada, attended structured (peer-assisted) or unstructured (nonpeer-assisted) SI sessions and completed a pre-/post-survey. Fifty-eight learners (39 systems (SYS) and 19 musculoskeletal (MSK) anatomy) completed both surveys and had responses analyzed. Both cohorts, maintained initial perceptions across pre-/post-analyses (MSK p = 0.1376 and SYS p = 0.3521). Resource usage was similar across both cohorts with discrepancies in skeletal model and textbook use. No MSK learner ranked any lab resources as "not at all useful." MSK learners felt more prepared to write a graded assessment (p = 0.0269), whereas SYS learners did not (p = 0.0680). Stratification of learners in MSK and SYS revealed learners spending between 30 and 60 min in SI sessions during the study period had the highest grades compared to students who spent less than 30 (p = 0.0286) or more than 60 (p = 0.0286) min attending SI sessions, respectively. Most learners in MSK (89.4%) and SYS (66%) concluded that they preferred structured over unstructured SI. Sentiment/thematic analysis using a generative AI-driven large language model revealed learners held positive perceptions of SI, emphasizing structured learning, resources, personalized learning, and support offered as the most prevalent themes surrounding SI. Ultimately, this study provides evidence that supports SI for improving student outcomes related to perceived preparedness for completing assessments and preferred teaching/learning styles in undergraduate human anatomy.


Assuntos
Anatomia , Avaliação Educacional , Grupo Associado , Humanos , Anatomia/educação , Masculino , Feminino , Avaliação Educacional/estatística & dados numéricos , Currículo , Ontário , Inquéritos e Questionários , Adulto Jovem , Aprendizagem , Liderança , Universidades , Educação de Graduação em Medicina/métodos , Adulto , Estudantes/psicologia , Estudantes/estatística & dados numéricos
10.
J Biol Chem ; 300(8): 107504, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38944123

RESUMO

Z-nucleic acid structures play vital roles in cellular processes and have implications in innate immunity due to their recognition by Zα domains containing proteins (Z-DNA/Z-RNA binding proteins, ZBPs). Although Zα domains have been identified in six proteins, including viral E3L, ORF112, and I73R, as well as, cellular ADAR1, ZBP1, and PKZ, their prevalence across living organisms remains largely unexplored. In this study, we introduce a computational approach to predict Zα domains, leading to the revelation of previously unidentified Zα domain-containing proteins in eukaryotic organisms, including non-metazoan species. Our findings encompass the discovery of new ZBPs in previously unexplored giant viruses, members of the Nucleocytoviricota phylum. Through experimental validation, we confirm the Zα functionality of select proteins, establishing their capability to induce the B-to-Z conversion. Additionally, we identify Zα-like domains within bacterial proteins. While these domains share certain features with Zα domains, they lack the ability to bind to Z-nucleic acids or facilitate the B-to-Z DNA conversion. Our findings significantly expand the ZBP family across a wide spectrum of organisms and raise intriguing questions about the evolutionary origins of Zα-containing proteins. Moreover, our study offers fresh perspectives on the functional significance of Zα domains in virus sensing and innate immunity and opens avenues for exploring hitherto undiscovered functions of ZBPs.


Assuntos
DNA Forma Z , Proteínas de Ligação a RNA , DNA Forma Z/química , DNA Forma Z/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/imunologia , Vírus Gigantes/metabolismo , Vírus Gigantes/genética , Vírus Gigantes/química , Domínios Proteicos , Proteínas Virais/química , Proteínas Virais/metabolismo , Proteínas Virais/imunologia , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Imunidade Inata , Humanos , Ligação Proteica
11.
Biomed Phys Eng Express ; 10(4)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38718784

RESUMO

A study of burn thresholds from superficially penetrating radio-frequency (RF) energy at 8.2 and 95 GHz for swine skin was conducted. The study determined the thresholds for superficial, partial-thickness, and full-thickness burn severities after 5 seconds of exposure at power densities of 4-30 W/cm2and 2-15 W/cm2at 8.2 and 95 GHz, respectively. There were significant differences in he burn thresholds at the different severities between the two frequencies due to the large difference in energy penetration depths. Biopsies were collected from each burn site at 1, 24, 72, and 168 hr post exposure. Each sample was assessed by a burn pathologist against 20 histological factors to characterize the damage resulting from these RF overexposures. A one-dimensional, layered digital phantom that utilized realistic values for dielectric and thermal properties was used to explain some observed thresholds. The results of the heating and cooling response of the animal model and histology scores of each exposure are provided to enhance future efforts at simulation of RF overexposures and to establish damage thresholds.


Assuntos
Queimaduras , Micro-Ondas , Pele , Animais , Micro-Ondas/efeitos adversos , Suínos , Pele/efeitos da radiação , Pele/patologia , Queimaduras/etiologia , Queimaduras/patologia , Imagens de Fantasmas , Ondas de Rádio/efeitos adversos , Temperatura Alta
12.
Cogn Emot ; : 1-13, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712807

RESUMO

Sustained attention, a key cognitive skill that improves during childhood and adolescence, tends to be worse in some emotional and behavioural disorders. Sustained attention is typically studied in non-affective task contexts; here, we used a novel task to index performance in affective versus neutral contexts across adolescence (N = 465; ages 11-18). We asked whether: (i) performance would be worse in negative versus neutral task contexts; (ii) performance would improve with age; (iii) affective interference would be greater in younger adolescents; (iv) adolescents at risk for depression and higher in anxiety would show overall worse performance; and (v) would show differential performance in negative contexts. Results indicated that participants performed more poorly in negative contexts and showed age-related performance improvements. Those at risk of depression performed more poorly than those at lower risk. However, there was no difference between groups as a result of affective context. For anxiety there was no difference in performance as a function of severity. However, those with higher anxiety showed less variance in their reaction times to negative stimuli than those with lower anxiety. One interpretation is that moderate levels of emotional arousal associated with anxiety make individuals less susceptible to the distracting effects of negative stimuli.

13.
Radiol Case Rep ; 19(8): 3080-3083, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38770385

RESUMO

Anomalous origin of the circumflex artery from the pulmonary artery (ACxAPA) is a rare but clinically significant condition in which the circumflex artery arises from either the main pulmonary artery or one of its main branches. Untreated patients with ACxAPA may develop severe heart failure or sudden cardiac death. Diagnosis is established with either catheter or CT angiography. We present a case of an adult male with no prior known cardiac history who was found to have ACxAPA after presenting to our institution in acute decompensated heart failure.

14.
Br J Haematol ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698705

RESUMO

Diagnosing chronic myeloid leukaemia (CML) during pregnancy is rare. Tyrosine kinase inhibitors (TKIs) have traditionally been contraindicated owing to their teratogenicity. Management decisions should consider the risks to mother and foetus of uncontrolled disease and teratogenic medications. Further cases are required to build upon the paucity of current literature. We report 22 cases of CML diagnosed during pregnancy from 2002 to date. Twenty-one pregnancies resulted in healthy babies and one patient miscarried. Some patients remained untreated throughout pregnancy but the majority received one or both of interferon-α and leucapheresis. One patient was started on imatinib at Week 26, and one on hydroxycarbamide in the third trimester. We report haematological parameters during pregnancy to provide clinicians with realistic expectations of management. There were no fetal abnormalities related to treatment during pregnancy. Seventeen patients achieved at least major molecular response on first-line TKI. A diagnosis of CML during pregnancy can be managed without significant consequences for mother or child. Leucapheresis and interferon-α are generally safe throughout pregnancy. Despite having been avoided previously, there is growing evidence that certain TKIs may be used in particular circumstances during the later stages of pregnancy. Future work should aim to further elucidate this safety profile.

15.
Microorganisms ; 12(4)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38674579

RESUMO

The bidirectional relationship between the gut microbiota and the nervous system is known as the microbiota-gut-brain axis (MGBA). The MGBA controls the complex interactions between the brain, the enteric nervous system, the gut-associated immune system, and the enteric neuroendocrine systems, regulating key physiological functions such as the immune response, sleep, emotions and mood, food intake, and intestinal functions. Psychobiotics are considered tools with the potential to modulate the MGBA through preventive, adjunctive, or curative approaches, but their specific mechanisms of action on many aspects of health are yet to be characterized. This narrative review and perspectives article highlights the key paradigms needing attention as the scope of potential probiotics applications in human health increases, with a growing body of evidence supporting their systemic beneficial effects. However, there are many limitations to overcome before establishing the extent to which we can incorporate probiotics in the management of neuropsychiatric disorders. Although this article uses the term probiotics in a general manner, it remains important to study probiotics at the strain level in most cases.

16.
Sci Rep ; 14(1): 8447, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38600121

RESUMO

Amniotes feature two principal visual processing systems: the tectofugal and thalamofugal pathways. In most mammals, the thalamofugal pathway predominates, routing retinal afferents through the dorsolateral geniculate complex to the visual cortex. In most birds, the thalamofugal pathway often plays the lesser role with retinal afferents projecting to the principal optic thalami, a complex of several nuclei that resides in the dorsal thalamus. This thalamic complex sends projections to a forebrain structure called the Wulst, the terminus of the thalamofugal visual system. The thalamofugal pathway in birds serves many functions such as pattern discrimination, spatial memory, and navigation/migration. A comprehensive analysis of avian species has unveiled diverse subdivisions within the thalamic and forebrain structures, contingent on species, age, and techniques utilized. In this study, we documented the thalamofugal system in three dimensions by integrating histological and contrast-enhanced computed tomography imaging of the avian brain. Sections of two-week-old chick brains were cut in either coronal, sagittal, or horizontal planes and stained with Nissl and either Gallyas silver or Luxol Fast Blue. The thalamic principal optic complex and pallial Wulst were subdivided on the basis of cell and fiber density. Additionally, we utilized the technique of diffusible iodine-based contrast-enhanced computed tomography (diceCT) on a 5-week-old chick brain, and right eyeball. By merging diceCT data, stained histological sections, and information from the existing literature, a comprehensive three-dimensional model of the avian thalamofugal pathway was constructed. The use of a 3D model provides a clearer understanding of the structural and spatial organization of the thalamofugal system. The ability to integrate histochemical sections with diceCT 3D modeling is critical to better understanding the anatomical and physiologic organization of complex pathways such as the thalamofugal visual system.


Assuntos
Imageamento Tridimensional , Vias Visuais , Animais , Vias Visuais/fisiologia , Tálamo/fisiologia , Prosencéfalo/fisiologia , Galinhas/fisiologia , Mamíferos
17.
Phys Rev Lett ; 132(13): 135301, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613270

RESUMO

The anomalous diffusion of particles and energy in magnetized plasma systems is a widespread phenomenon that can adversely impact their operation and preclude predictive models. In this Letter, this diffusion is characterized noninvasively in a low-temperature, Hall-type plasma. Laser-induced fluorescence and incoherent Thomson scattering measurements are combined with a 1D generalized Ohm's law to infer the time-averaged inverse Hall parameter, a transport coefficient that governs cross-field diffusion. While the measured diffusion profile agrees with model-based estimates in magnitude, the measurements do not exhibit the steep "transport barrier" typically imposed in models. Instead, these results show that the electric field is primarily driven by a diamagnetic contribution due to the large peak electron temperature exceeding 75 eV. This finding motivates a reconsideration of nonclassical energy transport across field lines in low-temperature plasmas.

18.
Biochemistry ; 63(6): 777-787, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38437710

RESUMO

The left-handed Z-conformation of nucleic acids can be adopted by both DNA and RNA when bound by Zα domains found within a variety of viral and innate immune response proteins. While Z-form adoption is preferred by certain sequences, such as the commonly studied (CpG)n repeats, Zα has been reported to bind to a wide range of sequence contexts. Studying how Zα interacts with B-/A-form helices prior to their conversion to the Z-conformation is challenging as binding coincides with Z-form adoption. Here, we studied the binding of Zα fromHomo sapiens ADAR1 to a locked "A-type" version of the (CpG)3 construct (LNA (CpG)3) where the sugar pucker is locked into the C3'-endo/C2'-exo conformation, which prevents the duplex from adopting the alternating C2'/C3'-endo sugar puckers found in the Z-conformation. Using NMR and other biophysical techniques, we find that ZαADAR1 binds to the LNA (CpG)3 using a similar interface as for Z-form binding, with a dissociation constant (KD) of ∼4 µM. In contrast to Z-DNA/Z-RNA, where two ZαADAR1 bind to every 6 bp stretch, our data suggests that ZαADAR1 binds to multiple LNA molecules, indicating a completely different binding mode. Because ZαADAR1 binds relatively tightly to a non-Z-form model, its binding to B/A-form helices may need to be considered when experiments are carried out which attempt to identify the Z-form targets of Zα domains. The use of LNA constructs may be beneficial in experiments where negative controls for Z-form adoption are needed.


Assuntos
DNA Forma Z , Ácidos Nucleicos , Conformação de Ácido Nucleico , Sítios de Ligação , RNA , Açúcares , Adenosina Desaminase/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-38437795

RESUMO

PURPOSE: To present a novel case of exogenous Rahnella aquatilis endophthalmitis following an intravitreal injection. METHODS: Case report. RESULTS: A 74-year-old male presented with acute progressive vision loss and pain in the left eye, 5 days after an intravitreal injection for diabetic macular edema. The patient was diagnosed with exogenous endophthalmitis and empirically treated with intravitreal injections of vancomycin and ceftazidime as well as topical and oral ciprofloxacin. In follow up two days later, the patient was treated with preoperative povidone-iodine followed by prompt vitrectomy with additional vancomycin and ceftazidime due to pharmacy sterile hood issues that delayed antibiotic availability. Microbiological cultures and two mass spectrometry identification tests confirmed the diagnosis of exogenous Rahnella aquatilis endophthalmitis. Despite the presence of scattered retinal hemorrhagic infarcts involving the macula and subsequent full-thickness atrophic macular holes seen in follow up, the patient achieved a favorable anatomical and functional outcome of BCVA 20/80 at 1 year of follow-up. CONCLUSION: This case highlights the occurrence of exogenous Rahnella aquatilis endophthalmitis following an intravitreal injection for diabetic macular edema. Prompt diagnosis and treatment produced a favorable outcome relative to other typical Gram-negative Enterobacteriaceae organisms.

20.
ESMO Open ; 9(3): 102388, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442452

RESUMO

BACKGROUND: The HER2DX risk-score has undergone rigorous validation in prior investigations involving patients with early-stage human epidermal growth factor receptor 2 (HER2)-positive (HER2+) breast cancer. In this study, we present the outcomes of the HER2DX risk-score within the most recent release of the Sweden Cancerome Analysis Network-Breast (SCAN-B) HER2+ cohort. This updated examination benefits from a larger patient sample, an extended follow-up duration, and detailed treatment information. MATERIALS AND METHODS: Clinical and RNAseq data from the SCAN-B dataset were retrieved from Gene Expression Omnibus (GSE81538). Among the 6600 patients, 819 had HER2+ breast cancer, with 757 individuals with research-based HER2DX risk-scores and corresponding survival outcomes. The HER2DX risk-score was evaluated (i) as a continuous variable and (ii) using predefined cut-offs. The primary endpoint for this study was overall survival (OS). The Kaplan-Meier method and Cox models were used to estimate OS and a multistate model with four states was fitted to better characterize patients' follow-up. RESULTS: The median follow-up time was 7.5 years (n = 757). The most common systemic therapy was chemotherapy with trastuzumab (82.0%) and most tumors were classified as T1-T2 (97.1%). The HER2DX risk-score as a continuous variable was significantly associated with OS after adjustment for clinical variables and treatment regimen [hazard ratios (HR) per 10-unit increment = 1.31, 95% confidence interval (CI) 1.13-1.51, P < 0.001] as well as within predefined risk groups (high versus low; HR = 2.57, 95% CI 1.36-4.85, P < 0.001). Patients classified as HER2DX high-risk also had higher risk of (i) breast cancer recurrence and (ii) death without previous recurrence. Within the subgroup of HER2+ T1N0 tumors (n = 297), those classified as high-risk demonstrated inferior OS compared to low-risk tumors (7-year OS 77.8% versus 96.8%, P < 0.001). The HER2DX mRNA ERBB2 score was associated with clinical HER2 status (area under the receiver operating characteristic curve = 0.91). CONCLUSIONS: In patients with early-stage HER2+ breast cancer, HER2DX risk-score provides prognostic information beyond clinicopathological variables, including treatment regimen with or without trastuzumab.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Prognóstico , Suécia/epidemiologia , Recidiva Local de Neoplasia/tratamento farmacológico , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico
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