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INTRODUCTION: This study aimed to assess the impact of midline lumbar fusion with cortical bone trajectory screws (MIDLF/CBT) on the multifidus muscles, focusing on the evaluation of their postoperative atrophy. CLINICAL RATIONALE FOR THE STUDY: MIDLF/CBT is a relatively new technique increasingly used to treat spinal instability. Despite its reduced invasiveness compared to traditional posterior lumbar interbody fusion with traditional pedicle screws (PLIF/TP), concerns remain about potential damage to the multifidus muscles that are crucial for spinal stability. Understanding the extent of muscular atrophy post-MIDLF/CBT is vital for improving surgical outcomes, and potentially patient rehabilitation strategies. MATERIAL AND METHODS: This study retrospectively analysed preoperative and postoperative MRI scans of patients who underwent MIDLF/CBT for degenerative segmental spondylolisthesis. The bilateral width of the multifidus muscles at the operated segment and adjacent segments was measured using axial T2-weighted MRI scans. Statistical comparisons were made using a paired t test, with significance set at p < 0.05. RESULTS: The study included 16 patients with an average age of 57 ± 10 years, 10 of whom (62.5%) were women, and featured a mean follow-up period of 37 ± 25 months. Postoperative measurements showed a significant reduction in the width of the multifidus muscles at the operated segment (mean difference -3.3mm, p = 0.02) and the inferior adjacent segment (-7.4 mm, p < 0.01). A decrease in muscle width at the superior adjacent segment was also observed, although this was not statistically significant. CONCLUSIONS AND CLINICAL IMPLICATIONS: Our study concluded that MIDLF/CBT results in significant multifidus muscle atrophy at and below the operated segment, potentially impacting postoperative rehabilitation and recovery. These findings highlight the need for further research comparing MIDLF/CBT to other spinal stabilisation techniques. Additionally, incorporating functional electromyographic assessments of paraspinal muscles could provide deeper insights into the long-term consequences of spinal surgeries and helpdevelop new approaches and strategies to mitigate paravertebral muscles atrophy, thus enhancing patient outcomes.
- Klíčová slova
- cortical bone trajectory, midline lumbar fusion, multifidus muscles, spinal fusion, spinal instability, spinal stabilisation,
- MeSH
- bederní obratle * chirurgie MeSH
- dospělí MeSH
- fúze páteře * škodlivé účinky metody MeSH
- hluboké zádové svaly * diagnostické zobrazování patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- pedikulární šrouby škodlivé účinky MeSH
- retrospektivní studie MeSH
- senioři MeSH
- spondylolistéza * chirurgie MeSH
- svalová atrofie * etiologie diagnostické zobrazování MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: MRI-only adaptive brachytherapy (MRI-ABT) is the state-of-the-art for treating locally advanced cervical cancer (LACC) in combination with concurrent chemoradiotherapy. We aimed to evaluate the pattern of pelvic recurrence after the treatment. MATERIAL AND METHODS: A total of one hundred LACC patients were treated between January 2017 and December 2023 with concurrent chemoradiotherapy of 45 Gy in 25 fractions ± boost to lymphadenopathy (up to a maximum dose of 60 Gy in 25 fractions) with concurrent weekly cisplatin chemotherapy at the dose of 40 mg/m2/week, and MR-ABT. RESULTS: At a median follow-up of 30.2 months, there were 2 local recurrences (2%) and 9 regional pelvic recurrences (9%). The median time to local/regional recurrence was 11 months (range 6-21). For all stages, the 3-year local control was 97.66%, and the 3-year pelvic control was 89.45%. Twenty-four patients died during follow-up; the 3-year overall survival was 75.11%, and the 3-year disease-free survival was 70.97%. CONCLUSION: MRI-ABT combined with external beam radiotherapy and concurrent chemotherapy for LACC demonstrates excellent local and regional pelvic control. Most local/regional recurrences occur inside or at the edge of the external-beam irradiated field. Recurrences inside the field of brachytherapy are rare. Distant recurrences are the predominant cause of death in LACC patients treated with definitive CRT and MRI-ABT.
- Klíčová slova
- Adaptive brachytherapy, Cervical cancer, MRI-only brachytherapy, Recurrence,
- MeSH
- brachyterapie * metody MeSH
- chemoradioterapie metody MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- lokální recidiva nádoru * MeSH
- magnetická rezonanční tomografie * metody MeSH
- nádory děložního čípku * patologie radioterapie diagnostické zobrazování terapie mortalita MeSH
- retrospektivní studie MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
A case report of a 68-year-old otherwise-healthy female patient with Spetzler-Martin (SM) grade I arteriovenous malformation (AVM) in her left frontal region is presented. After an uneventful surgery, cerebral venous infarction developed, and the patient was rendered hemiparetic with motor aphasia. After bony decompression, slow improvement was seen, and 3 months after surgery, the patient was neurologically intact. Six months after AVM resection, cranioplasty was performed. Infarction was caused by the thrombosis of a long primary draining vein, which finished its course in the normal cortical venous system. The case supports the venous origin of postoperative bleeding after AVM resection instead of the normal perfusion pressure phenomenon.
- Klíčová slova
- Cerebral arteriovenous malformation, venous occlusive disease,
- MeSH
- cerebrální infarkt * etiologie chirurgie MeSH
- intrakraniální arteriovenózní malformace * chirurgie komplikace MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mozkové žíly chirurgie diagnostické zobrazování MeSH
- pooperační komplikace etiologie chirurgie MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
During hypoxia, tissues are subjected to an inadequate oxygen supply, disrupting the balance needed to maintain normal function. This deficiency can occur due to reduced oxygen delivery caused by impaired blood flow or a decline in the blood's ability to carry oxygen. In tumors, hypoxia and vascularization play crucial roles, shaping their microenvironments and influencing cancer progression, response to treatment and metastatic potential. This chapter provides guidance on the use of non-invasive imaging methods including Positron Emission Tomography and Magnetic Resonance Imaging to study tumor oxygenation in pre-clinical settings. These imaging techniques offer valuable insights into tumor vascularity and oxygen levels, aiding in understanding tumor behavior and treatment effects. For example, PET imaging uses tracers such as [18F]-fluoromisonidazole (FMISO) to visualize hypoxic areas within tumors, while MRI complements this with anatomical and functional images. Although directly assessing tumor hypoxia with MRI remains challenging, techniques like Blood Oxygen Level Dependent (BOLD) and Dynamic Contrast-Enhanced MRI (DCE-MRI) provide valuable information. BOLD can track changes in oxygen levels during oxygen challenges, while DCE-MRI offers real-time access to perfusion and vessel permeability data. Integrating data from these imaging modalities can help assess oxygen supply, refine treatment strategies, enhance therapeutic effectiveness, and ultimately improve patient outcomes.
- Klíčová slova
- BOLD, DCE-MRI, FMISO, Hypoxia, Magnetic resonance imaging, Positron emission tomography, Preclinical, Tumor oxygenation, Vascularity,
- MeSH
- hypoxie * diagnostické zobrazování MeSH
- kyslík metabolismus MeSH
- lidé MeSH
- magnetická rezonanční tomografie * metody MeSH
- misonidazol analogy a deriváty MeSH
- myši MeSH
- nádorová hypoxie MeSH
- nádory * diagnostické zobrazování krevní zásobení patologie MeSH
- patologická angiogeneze * diagnostické zobrazování MeSH
- pozitronová emisní tomografie * metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fluoromisonidazole MeSH Prohlížeč
- kyslík MeSH
- misonidazol MeSH
Targeted Alpha Therapy (TAT) offers a promising approach to treat cancer, particularly micrometastases, by utilizing the short range and high linear energy transfer of alpha particles emitted by radionuclides. 211At (half-life 7.2h) is one of the promising alpha emitters (only one alpha emitted during decay) that has been identified for nuclear medicine applications. It belongs to the halogen family and shares chemical properties with iodine, an element used for imaging (123I, 124I and 131I) and also widely used to treat thyroid cancer (131I). This chemical similarity enables the use of Iodine as an analogue for biodistribution and dosimetry studies while using 211At for treatment in a theranostic approach. In this study, an alpha beam accelerated by SPIRAL2, was used to produce 211At via the reaction 209Bi(α, 2n)211At on the NFS beam line. The production cross section of 211At increases with increasing alpha energy up to 31 MeV. However, above 28.6 MeV, the production of 210At occurs via the 209Bi(α, 3n)210At reaction. 210At decays to 210Po, a highly toxic alpha-emitting radionuclide with a half-life of 138.3 days which cannot be separated chemically. Therefore, it is crucial to have a thorough understanding of the rise in 210At production to optimize the generation of 211At while minimizing the production of 210At To achieve this, 209Bi targets were irradiated at various alpha beam energies between 28 to 31 MeV with high precision thanks to the characteristics of SPIRAL2 accelerator and 210,211At cross sections were measured by using γ-ray spectroscopy. The incident particle flux was monitored using an instrumented Faraday cup. This flux measurement combined with the number of detected γ-rays allowed to determine the production cross sections of 210,211At as a function of energy. The results are in good agreement with experimental values recommended by the International Atomic Energy Agency (IAEA) for 211At and provide supplemental data for 210At between 28.6 and 31 MeV. The data collected in this study will help optimize the energy range of interest for the production of 211At and give 211At its rightful place as a radionuclide for TAT.
- Klíčová slova
- Production cross sections, Radionuclides: (210–211)At, α-particle induced reactions on (209)Bi, γ-ray spectroscopy,
- Publikační typ
- časopisecké články MeSH
Though bioconcentration of ionizable pharmaceuticals has received increased attention in fish and invertebrates, an understanding of bioconcentration of these contaminants of emerging concern by amphibians is lacking. Here, we investigated the bioconcentration, elimination and metabolism of a model weak base, the antihistamine diphenhydramine (DPH), at different developmental stages in the African clawed frog (Xenopus laevis), a well-established amphibian model. These developmental stages of X. laevis included tadpoles at pre-metamorphic stages (NF 49-52), tadpoles at pro-metamorphic and climax stages (NF 56-60) and newly metamorphosed frogs (NF 66). During metamorphosis from tadpoles to frogs, significant structural and functional changes occur in X. laevis, affecting respiration (gill resorption and lung development), feeding, digestion and skin structure. Animals were exposed to 10 μg/L DPH for 96 h, a concentration that did not affect mortality, development, growth, or behaviour, and then transferred to DPH-free water for 72 h. Relatively low steady-state bioconcentration factors (BCFSS) of DPH were determined, ranging from 21 to 36; kinetic BCF (BCFK) values ranged from 26 to 161. The depuration half-life (t1/2) and 95 % loss in the depuration phase (t95) of DPH were 19 and 20 h, and 83 and 85 h in pre-metamorphic and pro-metamorphic tadpoles, respectively. DPH had an approximately three times longer t1/2 (66 h) and a t95 (283 h) in juvenile frogs, suggesting differences in excretion and/or metabolism with age. Using non-targeted screening, DPH-N-oxide and DPH-N-desmethyl were identified at Schymanski level 2 as the exclusive DPH metabolites in all stages of X. laevis examined, indicating a major difference in the metabolism of DPH in frogs compared to other animals and humans. To our knowledge, this study provides initial observations for bioconcentration, elimination, and metabolism of an ionizable pharmaceutical in amphibians.
- Klíčová slova
- African clawed frog, Antihistamine, Bioconcentration factor, Depuration half-life, Development, Metabolite,
- MeSH
- biologická proměna MeSH
- chemické látky znečišťující vodu * metabolismus MeSH
- difenhydramin * metabolismus MeSH
- larva metabolismus MeSH
- Xenopus laevis * metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chemické látky znečišťující vodu * MeSH
- difenhydramin * MeSH
Plant materials that have been in contact with pesticides can be incorporated into the soil, posing a potential risk to non-target soil organisms and, hence, soil functions. This study investigated effects of two pesticides applied to maize leaves on the soil microbial community, activity and function. The herbicide prosulfocarb (PSC) and the fungicide boscalid (BSC) were applied alone or in combination to fresh or aged maize leaves, which were incorporated into soil. During a 56-day incubation we quantified pesticide residues in soil and maize leaves as well as maize-derived C incorporation into different microbial fractions (CO2, extractable organic carbon, microbial biomass and main microbial groups). Prosulfocarb residues on maize and in soil decreased to below 5 % after 56 days. However, BSC residues were transferred from maize into the soil, as indicated by an increase in BSC residues in soil of around 15 %. Prosulfocarb initially inhibited the synthesis of soil bacterial phospholipids by 25-45 %, which was accompanied by a decrease in the incorporation of maize-derived C into microbial biomass by 68-70 %. Following this, microorganisms shifted their nutrient acquisition strategy towards carbon and phosphorus, which led to increased utilization of easily available maize-derived C. Boscalid transiently inhibited the growth of soil fungi, reduced soil respiration, and mineralization of maize. In the future, pesticide accumulation through transfer from plant material into soils and the mode of action dependent effects on soil microorganisms need to be considered for risk assessment.
- Klíčová slova
- (13)C PLFA, Mode of action, Pesticide mixtures, SPRINT project, Soil enzymes, Substrate quality,
- MeSH
- bifenylové sloučeniny MeSH
- herbicidy * analýza toxicita metabolismus MeSH
- karbamáty * analýza metabolismus toxicita MeSH
- kukuřice setá * chemie metabolismus MeSH
- látky znečišťující půdu * analýza toxicita metabolismus MeSH
- listy rostlin chemie metabolismus MeSH
- niacinamid analogy a deriváty MeSH
- nitrily * analýza metabolismus toxicita MeSH
- průmyslové fungicidy * analýza toxicita metabolismus MeSH
- půda chemie MeSH
- půdní mikrobiologie * MeSH
- rezidua pesticidů * analýza toxicita metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- 2-chloro-N-(4-chlorobiphenyl-2-yl)nicotinamide MeSH Prohlížeč
- bifenylové sloučeniny MeSH
- herbicidy * MeSH
- karbamáty * MeSH
- látky znečišťující půdu * MeSH
- niacinamid MeSH
- nitrily * MeSH
- průmyslové fungicidy * MeSH
- půda MeSH
- rezidua pesticidů * MeSH
BACKGROUND AND OBJECTIVES: Isolated REM sleep behavior disorder (iRBD) is the strongest prodromal marker of synucleinopathies, including Parkinson disease (PD) and dementia with Lewy bodies (DLB). Identifying brain biomarkers that predict progression and distinguish phenoconversion trajectories remains a challenge. The glymphatic system is involved in interstitial waste clearance, and its dysfunction has been associated with pathologic protein accumulation and neurodegeneration. Diffusion tensor imaging along the perivascular space (DTI-ALPS) has been proposed as a noninvasive proxy for glymphatic function. The aim of this study was to determine whether patients with iRBD show a reduced DTI-ALPS index compared with controls and whether a lower DTI-ALPS index predicts future phenoconversion to PD or DLB. METHODS: We conducted a longitudinal, multicenter cohort study using brain MRI scans from patients with polysomnography-confirmed iRBD and healthy controls recruited across 5 international centers. All participants underwent T1-weighted and diffusion-weighted MRI. DTI-ALPS indices were computed from diffusivity along projection and associative fibers adjacent to the lateral ventricles. The primary outcome was time to phenoconversion to synucleinopathy. Linear models assessed baseline group differences and clinical correlates, and Cox proportional hazard models assessed the predictive value of DTI-ALPS for time to phenoconversion. RESULTS: A total of 250 patients with iRBD (mean age: 66.5 ± 6.8 years; 87% male) and 178 controls (65.7 ± 6.8 years; 81% male) were included. Patients with iRBD showed a lower left DTI-ALPS index compared with controls (mean difference = -0.034, 95% CI -0.067 to -0.001; p = 0.043). Of 224 patients with iRBD followed for a mean of 6.1 ± 3.5 years, 65 phenoconverted to a synucleinopathy. Converters had a lower left DTI-ALPS index than nonconverters (mean difference = -0.050, 95% CI -0.098 to -0.003; p = 0.038). Lower left DTI-ALPS index was associated with an increased risk of conversion to PD over time (hazard ratio = 2.43, 95% CI 1.13-5.25; p = 0.012). Other diffusion metrics inside periventricular masks, namely fractional anisotropy, diffusivity metrics, and free water, did not differ between groups. DISCUSSION: Patients with iRBD exhibit a reduced DTI-ALPS index, suggesting altered glymphatic function. This reduction was associated with future phenoconversion to PD, supporting the DTI-ALPS index as a potential prognostic MRI biomarker of progression in prodromal synucleinopathies.
- MeSH
- demence s Lewyho tělísky diagnostické zobrazování MeSH
- glymfatický systém * diagnostické zobrazování MeSH
- kohortové studie MeSH
- lidé středního věku MeSH
- lidé MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie MeSH
- mozek * diagnostické zobrazování MeSH
- Parkinsonova nemoc diagnostické zobrazování MeSH
- polysomnografie MeSH
- porucha chování v REM spánku * diagnostické zobrazování MeSH
- prodromální symptomy MeSH
- progrese nemoci MeSH
- senioři MeSH
- synukleinopatie diagnostické zobrazování MeSH
- zobrazování difuzních tenzorů * metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
Advances in the understanding of multiple sclerosis and the development of biomarkers of pathophysiology prompted a substantial revision of the 2017 McDonald diagnostic criteria. The new 2024 McDonald criteria provide a unified approach for diagnosing multiple sclerosis in individuals with relapsing or progressive courses throughout the lifespan (ie, from paediatric to late-life presentations). The optic nerve can now serve as a fifth anatomical location within the CNS for diagnosis. The central vein sign, paramagnetic rim lesions, and kappa free-light chain concentrations in CSF can be used, when available, to provide supportive evidence and confer specificity for a diagnosis of multiple sclerosis in specific situations. In certain cases, radiologically isolated syndrome or neurological symptoms that do not constitute a clear attack or progression of disability can fulfil the criteria for a multiple sclerosis diagnosis. We also provide guidance for the diagnosis of multiple sclerosis in older individuals (≥50 years) and those with comorbidities. The 2024 revised criteria should expedite the diagnosis of multiple sclerosis, while maintaining specificity.
- MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- roztroušená skleróza * diagnóza mozkomíšní mok MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Monitoring cognitive load is critical in diverse, demanding environments, yet conventional assessment methods face limitations in real-time applicability. While machine learning approaches using physiological signals show promise, they often require long data segments, exhibit high computational complexity, or neglect underlying causal dynamics. This paper proposes an efficient framework for cognitive load decoding using causal spatiotemporal patterns derived from multimodal peripheral biosignals. We introduce a novel feature engineering pipeline that transforms short signal segments into image-like representations capturing temporal dynamics via Gramian Angular Difference Fields and Motif Difference Fields, alongside causal interdependencies assessed using forward-backward copula Granger causality networks. These fused multimodal features are classified using a lightweight capsule neural network employing a self-attention routing mechanism. To evaluate the proposed solution, we conducted experiments on two widely used benchmark datasets, WESAD and CLAS. Our model achieved up to 94% accuracy using only 5-second signal segments, and maintained robust performance (84% accuracy) even with 1-second windows, a configuration rarely addressed in prior research. The proposed architecture includes only 323K trainable parameters, offering a favorable balance between model complexity and classification performance. The results confirm the framework's potential for computationally efficient, real-time cognitive load assessment suitable for resource-constrained environments and biofeedback applications.
- Klíčová slova
- Capsule network, Cognitive load, Electrocardiogram, Electrodermal activity, Machine learning, Pattern recognition, Physiology,
- MeSH
- kognice * fyziologie MeSH
- lidé MeSH
- neuronové sítě * MeSH
- počítačové zpracování signálu * MeSH
- strojové učení MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH