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2.
Micromachines (Basel) ; 15(9)2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39337817

ABSTRACT

In the framework of fully vertical GaN-on-Silicon device technology development, we report on the optimization of non-alloyed ohmic contacts on the N-polar n+-doped GaN face backside layer. This evaluation is made possible by using patterned TLMs (Transmission Line Model) through direct laser writing lithography after locally removing the substrate and buffer layers in order to access the n+-doped backside layer. As deposited non-alloyed metal stack on top of N-polar orientation GaN layer after buffer layers removal results in poor ohmic contact quality. To significantly reduce the related specific contact resistance, an HCl treatment is applied prior to metallization under various time and temperature conditions. A 3 min HCl treatment at 70 °C is found to be the optimum condition to achieve thermally stable high ohmic contact quality. To further understand the impact of the wet treatment, SEM (Scanning Electron Microscopy) and XPS (X-ray Photoelectron Spectroscopy) analyses were performed. XPS revealed a decrease in Ga-O concentration after applying the treatment, reflecting the higher oxidation susceptibility of the N-polar face compared to the Ga-polar face, which was used as a reference. SEM images of the treated samples show the formation of pyramids on the N-face after HCl treatment, suggesting specific wet etching planes of the GaN crystal from the N-face. The size of the pyramids is time-dependent; thus, increasing the treatment duration results in larger pyramids, which explains the degradation of ohmic contact quality after prolonged high-temperature HCl treatment.

3.
BMC Musculoskelet Disord ; 25(1): 744, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39285383

ABSTRACT

BACKGROUND: Most of the worldwide population is overweight and suffers from the resulting musculoskeletal comorbidities such as knee osteoarthritis or back pain. Practice guidelines recommend weight loss interventions for individuals suffering from these conditions. This systematic review investigated whether including a weight loss intervention in the musculoskeletal therapy of these individuals was cost-effective compared to administering the musculoskeletal therapy alone. METHODS: This study followed the PRISMA guidelines to systematically and independently search six databases and select full health economic evaluations published up to May 2024 from health care or societal perspectives according to predefined eligibility criteria. Cost data were standardised to 2023 Belgium Euros. The methodological quality was assessed using two health economic-specific checklists. RESULTS: The searches produced 5'305 references, of which 8 studies were selected for a total of 1'726 participants. The interventions consisted of different exercise plans and nutritional targets. Six values were in the north-eastern; leading to increased quality-adjusted life year (QALY) and higher costs; and two in the south-eastern quadrant of the cost-utility plane; leading to increased QALYs and lower costs. Two studies observed no differences in QALYs. Incremental cost utility ratios (ICUR) ranged from €13'580.10 to €34'412.40 per additional QALY from a healthcare perspective. From a societal perspective, the ICUR was €30'274.84. The included studies fulfilled 86 percent of the criteria in trial-based economic evaluations and 57 percent in model-based economic evaluations. The most common limitations of the studies were related to appropriate cost measures' specifications, research questions, time horizon choices, and sensitivity analyses. CONCLUSIONS: This systematic review showed weak but consistent evidence of cost-effectiveness for adding a weight loss intervention to musculoskeletal therapy for individuals with overweight, from either perspective. Further economic evaluations should evaluate the long-term cost-effectiveness of the intervention. TRIAL REGISTRATION: International Platform of Registered Systematic Review and Meta-analysis Protocols INPLASY (2022,110,122).


Subject(s)
Cost-Benefit Analysis , Obesity , Overweight , Quality-Adjusted Life Years , Humans , Obesity/therapy , Obesity/economics , Obesity/diagnosis , Overweight/therapy , Overweight/economics , Weight Loss , Musculoskeletal Diseases/therapy , Musculoskeletal Diseases/economics , Musculoskeletal Diseases/diagnosis , Weight Reduction Programs/economics , Weight Reduction Programs/methods , Health Care Costs/statistics & numerical data , Exercise Therapy/economics , Exercise Therapy/methods
4.
iScience ; 27(9): 110773, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39314240

ABSTRACT

Autosomal-dominant polycystic kidney disease (ADPKD) is a common monogenic disease characterized by the formation of fluid-filled renal cysts, loss of mitochondrial function, decreased fatty acid oxidation, increased glycolysis, and likely renal failure. We previously demonstrated that inducing a state of ketosis ameliorates or reverses PKD progression in multiple animal models. In this study, we compare time-restricted feeding and 48-h periodic fasting regimens in both juvenile and adult Cy/+ rats. Both fasting regimens potently prevent juvenile disease progression and partially reverse PKD in adults. To explore the mechanism of fasting, we administered ß-hydroxybutyrate (BHB) to Cy/+ rats and orthologous mouse models of PKD (Pkd1 RC/RC , Pkd1-Ksp:Cre). BHB recapitulated the effects of fasting in these models independent of stereoisomer, suggesting the effects of BHB are largely due to its signaling functions. These findings implicate the use of ketogenic metabolic therapy and BHB supplementation as potential disease modifiers of PKD and point toward underlying mechanisms.

5.
Nat Commun ; 15(1): 7740, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39231922

ABSTRACT

The physical characterization of proteins in terms of their sizes, interactions, and assembly states is key to understanding their biological function and dysfunction. However, this has remained a difficult task because proteins are often highly polydisperse and present as multicomponent mixtures. Here, we address this challenge by introducing single-molecule microfluidic diffusional sizing (smMDS). This approach measures the hydrodynamic radius of single proteins and protein assemblies in microchannels using single-molecule fluorescence detection. smMDS allows for ultrasensitive sizing of proteins down to femtomolar concentrations and enables affinity profiling of protein interactions at the single-molecule level. We show that smMDS is effective in resolving the assembly states of protein oligomers and in characterizing the size of protein species within complex mixtures, including fibrillar protein aggregates and nanoscale condensate clusters. Overall, smMDS is a highly sensitive method for the analysis of proteins in solution, with wide-ranging applications in drug discovery, diagnostics, and nanobiotechnology.


Subject(s)
Proteins , Single Molecule Imaging , Single Molecule Imaging/methods , Proteins/chemistry , Proteins/analysis , Solutions , Diffusion , Microfluidics/methods , Hydrodynamics , Microfluidic Analytical Techniques/methods
6.
Ophthalmologie ; 2024 Sep 14.
Article in German | MEDLINE | ID: mdl-39276227

ABSTRACT

BACKGROUND: In view of the predicted increase in incidence and prevalence of chronic retinal diseases and undersupply of care in the population, telemedicine could contribute to reducing access barriers to healthcare and improving the results of treatment. OBJECTIVE: A literature review on remote monitoring of chronic retinal diseases was carried out. MATERIAL AND METHODS: The medical literature was searched for publications on remote monitoring of chronic retinal diseases. The results were compiled in a narrative overview. RESULTS: The four main topics in the literature are: validation studies, implementation strategies, acceptance/target group analyses and health economic analyses. Remote monitoring systems are based on visual function tests, imaging or patient reports and have been particularly investigated in age-related macular degeneration (AMD) and diabetic eye disease (DED). Studies indicate positive effects regarding an optimization of clinical care and a favorable safety profile but randomized controlled trials are lacking for the majority of monitoring tools. CONCLUSION: Remote monitoring could complement existing care structures for patients with chronic retinal diseases, especially AMD and DED. Promising systems are based on hyperacuity or optical coherence tomography, while patient-reported data are not commonly used; however, there is currently insufficient evidence justifying the use of remote monitoring systems in chronic retinal diseases in Europe and more research on the validation of remote monitoring systems is needed.

7.
Cell Rep Med ; 5(9): 101696, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39178856

ABSTRACT

Pancreatic adenocarcinoma (PDAC) is one the most intractable cancers, in part due to its highly inflammatory microenvironment and paucity of infiltrating dendritic cells (DCs). Here, we find that genetic ablation or antibody blockade of tumor necrosis factor receptor 1 (TNFR1) enhanced intratumor T cell activation and slowed PDAC growth. While anti-PD-1 checkpoint inhibition alone had little effect, it further enhanced intratumor T cell activation in combination with anti-TNFR1. The major cellular alteration in the tumor microenvironment in the absence of TNFR1 signaling was a large increase in DC number and immunostimulatory phenotype. This may reflect a direct effect on DCs, because TNF induced TNFR1-dependent apoptosis of bone-marrow-derived DCs. The therapeutic response to anti-TNFR1 alone was superior to the combination of DC-activating agonistic anti-CD40 and Flt3 ligand (Flt3L). These observations suggest that targeting TNFR1, perhaps in concert with other strategies that promote DC generation and mobilization, may have therapeutic benefits.


Subject(s)
Dendritic Cells , Pancreatic Neoplasms , Receptors, Tumor Necrosis Factor, Type I , Signal Transduction , Animals , Humans , Mice , Apoptosis , Cell Line, Tumor , Cell Proliferation , Dendritic Cells/metabolism , Lymphocyte Activation/immunology , Mice, Inbred C57BL , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/immunology , Receptors, Tumor Necrosis Factor, Type I/metabolism , Receptors, Tumor Necrosis Factor, Type I/genetics , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Tumor Microenvironment
8.
Curr Eye Res ; : 1-5, 2024 Aug 18.
Article in English | MEDLINE | ID: mdl-39155542

ABSTRACT

PURPOSE: Specific genetic factors might serve as markers for risk stratification of AMD progression, but their association with key features of AMD has not been fully elucidated. Thus, we investigated the association between overall and pathway-specific genetic risk scores (GRS) and lead loci (ARMS2, CFH) with AMD stages and features of high-risk nonlate AMD, including reticular pseudodrusen (RPD) and large drusen area (LDA). METHODS: We performed a cross-sectional analysis of data from the Rhineland Study, a population-based study in Bonn, Germany. We included 4016 individuals aged 50 years and older of European descent. GRS and pathway-specific subscores were constructed based on a large genome-wide association study of AMD. Subscores were generated based on gene-pathways associations (complement, extracellular matrix remodeling (ECM) and lipid metabolism). Associations were assessed using logistic and multinomial regression. RESULTS: The mean age of participants was 63.36 years and 1813 (45.1%) were men. The GRS was positive in 48.1% of individuals and increased, but did not fully overlap, across AMD stages. Pathway-specific subscores increased across AMD stages except for the ECM subscore, which only showed a trend for increasing in late AMD. Increasing overall GRS was associated with RPD and LDA (OR [95%CI] for RPD: 1.70 [1.33-2.15], for LDA: 1.64 [1.29-2.07]) among individuals with AMD. Similarly, higher complement and ECM subscores was associated with RPD, while for LDA, only an association with complement subscore was observed. CONCLUSIONS: In a population-based setting, we confirmed higher genetic risk to be associated with more severe AMD and identified associations with high-risk features of intermediate AMD. Conjoint analyses suggested that high-risk features and late AMD might be differentially associated with genetic architecture in AMD, such as ECM remodeling. Incorporation of genetic information such as GRSs might improve AMD risk prediction strategies.

9.
Sci Rep ; 14(1): 19783, 2024 08 26.
Article in English | MEDLINE | ID: mdl-39187515

ABSTRACT

The prognosis of pancreatic cancer (PDAC) after tumor resection remains poor, mostly due to a high but variable risk of recurrence. A promising tool for improved prognostication is the quantification of CT tumor enhancement. For this, various enhancement formulas have been used in previous studies. However, a systematic comparison of these formulas is lacking. In the present study, we applied twenty-three previously published CT enhancement formulas to our cohort of 92 PDAC patients who underwent upfront surgery. We identified seven formulas that could reliably predict tumor recurrence. Using these formulas, weak tumor enhancement was associated with tumor recurrence at one and two years after surgery (p ≤ 0.030). Enhancement was inversely associated with adverse clinicopathological features. Low enhancement values were predictive of a high recurrence risk (Hazard Ratio ≥ 1.659, p ≤ 0.028, Cox regression) and a short time to recurrence (TTR) (p ≤ 0.027, log-rank test). Some formulas were independent predictors of TTR in multivariate models. Strikingly, almost all of the best-performing formulas measure solely tumor tissue, suggesting that normalization to non-tumor structures might be unnecessary. Among the top performers were also the absolute arterial/portal venous tumor attenuation values. These can be easily implemented in clinical practice for better recurrence prediction, thus potentially improving patient management.


Subject(s)
Neoplasm Recurrence, Local , Pancreatic Neoplasms , Tomography, X-Ray Computed , Humans , Pancreatic Neoplasms/surgery , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/pathology , Male , Female , Neoplasm Recurrence, Local/diagnostic imaging , Aged , Tomography, X-Ray Computed/methods , Middle Aged , Prognosis , Aged, 80 and over
10.
Cancers (Basel) ; 16(16)2024 Aug 18.
Article in English | MEDLINE | ID: mdl-39199642

ABSTRACT

Glutamine (Gln) is a non-essential amino acid that is involved in the development and progression of several malignancies, including prostate cancer (PCa). While Gln is non-essential for non-malignant prostate epithelial cells, PCa cells become highly dependent on an exogenous source of Gln. The Gln metabolism in PCa is tightly controlled by well-described oncogenes such as MYC, AR, and mTOR. These oncogenes contribute to therapy resistance and progression to the aggressive castration-resistant PCa. Inhibition of Gln catabolism impedes PCa growth, survival, and tumor-initiating potential while sensitizing the cells to radiotherapy. Therefore, given its significant role in tumor growth, targeting Gln metabolism is a promising approach for developing new therapeutic strategies. Ongoing clinical trials evaluate the safety and efficacy of Gln catabolism inhibitors in combination with conventional and targeted therapies in patients with various solid tumors, including PCa. Further understanding of how PCa cells metabolically interact with their microenvironment will facilitate the clinical translation of Gln inhibitors and help improve therapeutic outcomes. This review focuses on the role of Gln in PCa progression and therapy resistance and provides insights into current clinical trials.

11.
Surv Ophthalmol ; 69(6): 851-869, 2024.
Article in English | MEDLINE | ID: mdl-39097172

ABSTRACT

We provide an overview of the expanding literature on the role of cytokines and immune mediators in pathophysiology of age-related macular degeneration (AMD). Although many immunological mediators have been linked to AMD pathophysiology, the broader mechanistic picture remains unclear with substantial variations in the levels of evidence supporting these mediators. Therefore, we reviewed the literature considering the varying levels of supporting evidence. A Medical Subject Headings (MeSH) term-based literature research was conducted in September, 2023, consisting of the MeSH terms "cytokine" and "Age-related macular degeneration" connected by the operator "AND". After screening the publications by title, abstract, and full text, a total of 146 publications were included. The proinflammatory cytokines IL-1ß (especially in basic research studies), IL-6, IL-8, IL-18, TNF-α, and MCP-1 are the most extensively characterised cytokines/chemokines, highlighting the role of local inflammasome activation and altered macrophage function in the AMD pathophysiology. Among the antiinflammatory mediators IL-4, IL-10, and TGF-ß were found to be the most extensively characterised, with IL-4 driving and IL-10 and TGF-ß suppressing disease progression. Despite the extensive literature on this topic, a profound understanding of AMD pathophysiology has not yet been achieved. Therefore, further studies are needed to identify potential therapeutic targets, followed by clinical studies.


Subject(s)
Cytokines , Macular Degeneration , Humans , Macular Degeneration/immunology , Macular Degeneration/physiopathology , Cytokines/metabolism
12.
J Vasc Interv Radiol ; 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39047935

ABSTRACT

PURPOSE: To assess immunogenic effects in unembolized contralateral tumor after single lobar yttrium-90 transarterial radioembolization (90Y-TARE) of colorectal liver metastases (CRLMs). MATERIAL AND METHODS: The analysis comprised 10 patients with microsatellite stable (MSS) CRLM scheduled for staged treatment in the prospective AROMA trial. Eligibility criteria included bilobar metastatic disease with >5 lesions without any treatment within 3 weeks. Baseline biopsy was followed by initial 90Y-TARE treatment of 1 liver lobe, followed by a second biopsy of yet untreated tumors in the other liver lobe at a median of 13 days (range, 4-49 days) immediately before second treatment. Tumor biopsies and peripheral blood mononuclear cells (PBMCs) were collected before treatments for immune cell analysis. Patients were stratified into responders and nonresponders based on tumor control or progression during follow-up. RESULTS: At baseline, responders (n = 4) displayed lower concentrations of FoxP3+ cells and colocation of CD4+FoxP3+ cells than nonresponders (both P = .02) in tumor tissues. At second biopsy, nonresponders showed a higher CD68+ macrophage density (P = .0014) than responders. Responders displayed fewer CD4+FoxP3+ T cells than CD8+ T cells at all time points (P = .02 and P = .0428). Nonresponders demonstrated a trending increase in CD68+ macrophages (P = .062), as well as a higher CD8+PD1+/CD8+ ratio (P = .062). PBMCs of nonresponders displayed lower CD8+PD1+ T cells and CD8+PD1+/CD8+ ratio at both time points. CONCLUSIONS: 90Y-TARE induces local immunogenic effects in nonexposed MSS CRLM, as well as systemic exhaustion of immune cells in nonresponders. Clinical implications such as a prognostic role or synergism of 90Y-TARE and checkpoint inhibition in MSS CRLM warrant further investigation.

13.
Sci Adv ; 10(28): eadn4824, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38985872

ABSTRACT

Molecular chaperones are central to the maintenance of proteostasis in living cells. A key member of this protein family is trigger factor (TF), which acts throughout the protein life cycle and has a ubiquitous role as the first chaperone encountered by proteins during synthesis. However, our understanding of how TF achieves favorable interactions with such a diverse substrate base remains limited. Here, we use microfluidics to reveal the thermodynamic determinants of this process. We find that TF binding to empty 70S ribosomes is enthalpy-driven, with micromolar affinity, while nanomolar affinity is achieved through a favorable entropic contribution for both intrinsically disordered and folding-competent nascent chains. These findings suggest a general mechanism for cotranslational TF function, which relies on occupation of the exposed TF-substrate binding groove rather than specific complementarity between chaperone and nascent chain. These insights add to our wider understanding of how proteins can achieve broad substrate specificity.


Subject(s)
Protein Binding , Thermodynamics , Substrate Specificity , Protein Biosynthesis , Escherichia coli Proteins/metabolism , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Ribosomes/metabolism , Protein Folding , Peptidylprolyl Isomerase
14.
Sci Adv ; 10(27): eadl5822, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38959317

ABSTRACT

The importance of phosphorus (P) in regulating ecosystem responses to climate change has fostered P-cycle implementation in land surface models, but their CO2 effects predictions have not been evaluated against measurements. Here, we perform a data-driven model evaluation where simulations of eight widely used P-enabled models were confronted with observations from a long-term free-air CO2 enrichment experiment in a mature, P-limited Eucalyptus forest. We show that most models predicted the correct sign and magnitude of the CO2 effect on ecosystem carbon (C) sequestration, but they generally overestimated the effects on plant C uptake and growth. We identify leaf-to-canopy scaling of photosynthesis, plant tissue stoichiometry, plant belowground C allocation, and the subsequent consequences for plant-microbial interaction as key areas in which models of ecosystem C-P interaction can be improved. Together, this data-model intercomparison reveals data-driven insights into the performance and functionality of P-enabled models and adds to the existing evidence that the global CO2-driven carbon sink is overestimated by models.


Subject(s)
Carbon Cycle , Carbon Dioxide , Eucalyptus , Forests , Phosphorus , Eucalyptus/metabolism , Carbon Dioxide/metabolism , Phosphorus/metabolism , Photosynthesis , Climate Change , Ecosystem , Carbon/metabolism , Models, Theoretical , Carbon Sequestration
15.
ACS Appl Polym Mater ; 6(12): 7088-7101, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38961861

ABSTRACT

Functional silanes are multifaceted cross-linkers, compatibilizers, coupling agents, and surface modifiers. Herein, we present organofunctional polysiloxane building blocks that offer great versatility in terms of molecular weight, degree of condensation, and the choice and loading of organic substituent groups. The organofunctional polyethoxysilanes (funPEOS) are prepared in a one-pot, two-step process: synthesis of the PEOS carrier/substrate, followed by grafting a functional silane "shell", both based on condensation with acetic anhydride. The reaction was optimized at the lab scale and scaled up to a 7 L reactor. The acetylation, condensation, and hyperbranched structure of the carrier were confirmed by 29Si NMR, while 29Si-29Si 2D INADEQUATE NMR provides strong evidence for the grafting of functional silanes onto the carrier (Q-T coupling). IR, 1H, and 13C NMR spectroscopy demonstrate that the functional groups remain intact. The molar mass can be tailored by stoichiometric control of the acetic anhydride to silane monomer ratio (M n 3500-20,000 g/mol). The compounds are stable organic liquids with a long shelf life. Selected applications are presented: scratch-resistant coatings with water contact angles of ∼90°, stable water emulsions, and surfactant-free, mesoporous silica foams.

16.
J Med Chem ; 67(14): 11975-11988, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-38981131

ABSTRACT

The postsynaptic density (PSD) comprises numerous scaffolding proteins, receptors, and signaling molecules that coordinate synaptic transmission in the brain. Postsynaptic density protein 95 (PSD-95) is a master scaffold protein within the PSD and one of its most abundant proteins and therefore constitutes a very attractive biomarker of PSD function and its pathological changes. Here, we exploit a high-affinity inhibitor of PSD-95, AVLX-144, as a template for developing probes for molecular imaging of the PSD. AVLX-144-based probes were labeled with the radioisotopes fluorine-18 and tritium, as well as a fluorescent tag. Tracer binding showed saturable, displaceable, and uneven distribution in rat brain slices, proving effective in quantitative autoradiography and cell imaging studies. Notably, we observed diminished tracer binding in human post-mortem Parkinson's disease (PD) brain slices, suggesting postsynaptic impairment in PD. We thus offer a suite of translational probes for visualizing and understanding PSD-related pathologies.


Subject(s)
Brain , Disks Large Homolog 4 Protein , Post-Synaptic Density , Animals , Humans , Disks Large Homolog 4 Protein/metabolism , Brain/metabolism , Brain/diagnostic imaging , Rats , Post-Synaptic Density/metabolism , Molecular Imaging/methods , Fluorine Radioisotopes/chemistry , Parkinson Disease/metabolism , Parkinson Disease/diagnostic imaging , Peptides/chemistry , Peptides/metabolism , Molecular Probes/chemistry , Male , Autoradiography , Rats, Sprague-Dawley , Tritium , Pyridines , Pyrrolidinones
17.
NPJ Parkinsons Dis ; 10(1): 139, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39075088

ABSTRACT

α-Synuclein (α-syn) accumulates as insoluble amyloid but also forms soluble α-syn oligomers (αSOs), thought to be even more cytotoxic than fibrils. To detect and block the unwanted activities of these αSOs, we have raised 30 monoclonal antibodies (mAbs) against different forms of αSOs, ranging from unmodified αSOs to species stabilized by lipid peroxidation products and polyphenols, αSOs formed by C-terminally truncated α-syn, and multivalent display of α-syn on capsid virus-like particles (cVLPs). While the mAbs generally show a preference for αSOs, they also bind fibrils, but to variable extents. Overall, we observe great diversity in the mAbs' relative affinities for monomers and αSOs, varied requirements for the C-terminal extension of α-syn, and only a modest effect on α-syn fibrillation. Several mAbs show several orders of magnitude preference for αSOs over monomers in in-solution studies, while the commercial antibody MJF14 only bound 10-fold more strongly to αSOs than monomeric α-syn. Gratifyingly, seven mAbs almost completely block αSO permeabilization of membrane vesicles. Five selected mAbs identified α-syn-related pathologies like Lewy bodies (LBs) and Lewy Neurites, as well as Glial Cytoplasmic Inclusions in postmortem brains from people diagnosed for PD, dementia with LBs or multiple system atrophy, although to different extents. Three mAbs were particularly useful for pathological evaluation of postmortem brain human tissue, including early stages of PD. Although there was no straightforward connection between the mAbs' biophysical and immunohistochemical properties, it is encouraging that this comprehensive collection of mAbs able to recognize different aggregated α-syn species in vitro also holds diagnostic potential.

18.
BMC Genomics ; 25(1): 669, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961363

ABSTRACT

Next-generation risk assessment relies on mechanistic data from new approach methods, including transcriptome data. Various technologies, such as high-throughput targeted sequencing methods and microarray technologies based on hybridization with complementary probes, are used to determine differentially expressed genes (DEGs). The integration of data from different technologies requires a good understanding of the differences arising from the use of various technologies.To better understand the differences between the TempO-Seq platform and Affymetrix chip technology, whole-genome data for the volatile compound dimethylamine were compared. Selected DEGs were also confirmed using RTqPCR validation. Although the overlap of DEGs between TempO-Seq and Affymetrix was no higher than 37%, a comparison of the gene regulation in terms of log2fold changes revealed a very high concordance. RTqPCR confirmed the majority of DEGs from either platform in the examined dataset. Only a few conflicts were found (11%), while 22% were not confirmed, and 3% were not detected.Despite the observed differences between the two platforms, both can be validated using RTqPCR. Here we highlight some of the differences between the two platforms and discuss their applications in toxicology.


Subject(s)
Gene Expression Profiling , Oligonucleotide Array Sequence Analysis , Oligonucleotide Array Sequence Analysis/methods , Gene Expression Profiling/methods , High-Throughput Nucleotide Sequencing/methods , Humans , Real-Time Polymerase Chain Reaction/methods
19.
Ups J Med Sci ; 1292024.
Article in English | MEDLINE | ID: mdl-38863725

ABSTRACT

Background: The development of bispecific antibodies that can traverse the blood-brain barrier has paved the way for brain-directed immunotherapy and when radiolabelled, immunoPET imaging. The objective of this study was to investigate how indium-111 (111In) radiolabelling with compatible chelators affects the brain delivery and peripheral biodistribution of the bispecific antibody RmAb158-scFv8D3, which binds to amyloid-beta (Aß) and the transferrin receptor (TfR), in Aß pathology-expressing tg-ArcSwe mice and aged-matched wild-type control mice. Methods: Bispecific RmAb158-scFv8D3 (biAb) was radiolabelled with 111In using CHX-A"-DTPA, DOTA, or DOTA-tetrazine (DOTA-Tz). Affinity toward TfR and Aß, as well as stability, was investigated in vitro. Mice were then intravenously administered with the three different radiolabelled biAb variants, and blood samples were collected for monitoring pharmacokinetics. Brain concentration was quantified after 2 and 72 h, and organ-specific retention was measured at 72 h by gamma counting. A subset of mice also underwent whole-body Single-photon emission computed tomography (SPECT) scanning at 72 h after injection. Following post-mortem isolation, the brains of tg-ArcSwe and WT mice were sectioned, and the spatial distribution of biAb was further investigated with autoradiography. Results: All three [111In]biAb variants displayed similar blood pharmacokinetics and brain uptake at 2 h after administration. Radiolabelling did not compromise affinity, and all variants showed good stability, especially the DOTA-Tz variant. Whole-body SPECT scanning indicated high liver, spleen, and bone accumulation of all [111In]biAb variants. Subsequent ex vivo measurement of organ retention confirmed SPECT data, with retention in the spleen, liver, and bone - with very high bone marrow retention. Ex vivo gamma measurement of brain tissue, isolated at 72 h post-injection, and ex vivo autoradiography showed that WT mice, despite the absence of Aß, exhibited comparable brain concentrations of [111In]biAb as those found in the tg-ArcSwe brain. Conclusions: The successful 111In-labelling of biAb with retained binding to TfR and Aß, and retained ability to enter the brain, demonstrated that 111In can be used to generate radioligands for brain imaging. A high degree of [111In]biAb in bone marrow and intracellular accumulation in brain tissue indicated some off-target interactions or potential interaction with intrabrain TfR resulting in a relatively high non-specific background signal.


Subject(s)
Amyloid beta-Peptides , Brain , Indium Radioisotopes , Tomography, Emission-Computed, Single-Photon , Animals , Tomography, Emission-Computed, Single-Photon/methods , Mice , Brain/diagnostic imaging , Brain/metabolism , Tissue Distribution , Amyloid beta-Peptides/metabolism , Mice, Transgenic , Antibodies, Bispecific/pharmacokinetics , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/diagnostic imaging , Receptors, Transferrin/metabolism , Receptors, Transferrin/immunology , Radiopharmaceuticals/pharmacokinetics , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/metabolism
20.
Ecol Evol ; 14(6): e11517, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38895582

ABSTRACT

Understanding the biophysical limitations on forest carbon across diverse ecological regions is crucial for accurately assessing and managing forest carbon stocks. This study investigates the role of climate and disturbance on the spatial variation of two key forest carbon pools: aboveground carbon (AGC) and soil organic carbon (SOC). Using plot-level carbon pool estimates from Nepal's national forest inventory and structural equation modelling, we explore the relationship of forest carbon stocks to broad-scale climatic water and energy availability and fine-scale terrain and disturbance. The forest AGC and SOC models explained 25% and 59% of the observed spatial variation in forest AGC and SOC, respectively. Among the evaluated variables, disturbance exhibited the strongest negative correlation with AGC, while the availability of climatic energy demonstrated the strongest negative correlation with SOC. Disturbances such as selective logging and firewood collection result in immediate forest carbon loss, while soil carbon changes take longer to respond. The lower decomposition rates in the high-elevation region, due to lower temperatures, preserve organic matter and contribute to the high SOC stocks observed there. These results highlight the critical role of climate and disturbance regimes in shaping landscape patterns of forest carbon stocks. Understanding the underlying drivers of these patterns is crucial for forest carbon management and conservation across diverse ecological zones including the Central Himalayas.

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