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1.
Imeta ; 3(4): e221, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39135698

ABSTRACT

Functional cure for chronic hepatitis B (CHB) remains challenging due to the lack of direct intervention methods for hepatic inflammation. Multi-omics research offers a promising approach to understand hepatic inflammation mechanisms in CHB. A Bayesian linear model linked gene expression with clinical parameters, and population-specific expression analysis (PSEA) refined bulk gene expression into specific cell types across different clinical phases. These models were integrated into our analysis of key factors like inflammatory cells, immune activation, T cell exhaustion, chemokines, receptors, and interferon-stimulated genes (ISGs). Validation through multi-immune staining in liver specimens from CHB patients bolstered our findings. In CHB patients, increased gene expression related to immune cell activation and migration was noted. Marker genes of macrophages, T cells, immune-negative regulators, chemokines, and ISGs showed a positive correlation with serum alanine aminotransferase (ALT) levels but not hepatitis B virus DNA levels. The PSEA model confirmed T cells as the source of exhausted regulators, while macrophages primarily contributed to chemokine expression. Upregulated ISGs (ISG20, IFI16, TAP2, GBP1, PSMB9) in the hepatitis phase were associated with T cell and macrophage infiltration and positively correlated with ALT levels. Conversely, another set of ISGs (IFI44, ISG15, IFI44L, IFI6, MX1) mainly expressed by hepatocytes and B cells showed no correlation with ALT levels. Our study presents a multi-omics analysis integrating bulk transcriptomic, single-cell sequencing data, and clinical data from CHB patients to decipher the cause of intrahepatic inflammation in CHB. The findings confirm that macrophages secrete chemokines like CCL20, recruiting exhausted T cells into liver tissue; concurrently, hepatocyte innate immunity is suppressed, hindering the antiviral effects of ISGs.

2.
J Med Virol ; 96(7): e29789, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38988206

ABSTRACT

Merkel cell carcinoma (MCC) is a highly aggressive skin cancer associated with integration of Merkel cell polyomavirus (MCPyV). MCPyV-encoded T-antigens (TAs) are pivotal for sustaining MCC's oncogenic phenotype, i.e., repression of TAs results in reactivation of the RB pathway and subsequent cell cycle arrest. However, the MCC cell line LoKe, characterized by a homozygous loss of the RB1 gene, exhibits uninterrupted cell cycle progression after shRNA-mediated TA repression. This unique feature allows an in-depth analysis of the effects of TAs beyond inhibition of the RB pathway, revealing the decrease in expression of stem cell-related genes upon panTA-knockdown. Analysis of gene regulatory networks identified members of the E2F family (E2F1, E2F8, TFDP1) as key transcriptional regulators that maintain stem cell properties in TA-expressing MCC cells. Furthermore, minichromosome maintenance (MCM) genes, which encodes DNA-binding licensing proteins essential for stem cell maintenance, were suppressed upon panTA-knockdown. The decline in stemness occurred simultaneously with neural differentiation, marked by the increased expression of neurogenesis-related genes such as neurexins, BTG2, and MYT1L. This upregulation can be attributed to heightened activity of PBX1 and BPTF, crucial regulators of neurogenesis pathways. The observations in LoKe were confirmed in an additional MCPyV-positive MCC cell line in which RB1 was silenced before panTA-knockdown. Moreover, spatially resolved transcriptomics demonstrated reduced TA expression in situ in a part of a MCC tumor characterized by neural differentiation. In summary, TAs are critical for maintaining stemness of MCC cells and suppressing neural differentiation, irrespective of their impact on the RB-signaling pathway.


Subject(s)
Antigens, Polyomavirus Transforming , Antigens, Viral, Tumor , Merkel cell polyomavirus , Neoplastic Stem Cells , Retinoblastoma Binding Proteins , Humans , Antigens, Viral, Tumor/genetics , Antigens, Viral, Tumor/metabolism , Carcinoma, Merkel Cell/virology , Carcinoma, Merkel Cell/genetics , Cell Differentiation , Cell Line, Tumor , Gene Knockdown Techniques , Gene Regulatory Networks , Merkel cell polyomavirus/genetics , Neoplastic Stem Cells/virology , Neoplastic Stem Cells/metabolism , Neurons/virology , Retinoblastoma Binding Proteins/genetics , Retinoblastoma Binding Proteins/metabolism , Skin Neoplasms/virology , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Antigens, Polyomavirus Transforming/genetics , Antigens, Polyomavirus Transforming/metabolism
3.
Nat Med ; 30(6): 1771-1783, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38890531

ABSTRACT

Minimally invasive biomarkers are urgently needed to detect molecular pathology in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Here, we show that plasma extracellular vesicles (EVs) contain quantifiable amounts of TDP-43 and full-length tau, which allow the quantification of 3-repeat (3R) and 4-repeat (4R) tau isoforms. Plasma EV TDP-43 levels and EV 3R/4R tau ratios were determined in a cohort of 704 patients, including 37 genetically and 31 neuropathologically proven cases. Diagnostic groups comprised patients with TDP-43 proteinopathy ALS, 4R tauopathy progressive supranuclear palsy, behavior variant FTD (bvFTD) as a group with either tau or TDP-43 pathology, and healthy controls. EV tau ratios were low in progressive supranuclear palsy and high in bvFTD with tau pathology. EV TDP-43 levels were high in ALS and in bvFTD with TDP-43 pathology. Both markers discriminated between the diagnostic groups with area under the curve values >0.9, and between TDP-43 and tau pathology in bvFTD. Both markers strongly correlated with neurodegeneration, and clinical and neuropsychological markers of disease severity. Findings were replicated in an independent validation cohort of 292 patients including 34 genetically confirmed cases. Taken together, the combination of EV TDP-43 levels and EV 3R/4R tau ratios may aid the molecular diagnosis of FTD, FTD spectrum disorders and ALS, providing a potential biomarker to monitor disease progression and target engagement in clinical trials.


Subject(s)
Amyotrophic Lateral Sclerosis , Biomarkers , DNA-Binding Proteins , Extracellular Vesicles , Frontotemporal Dementia , tau Proteins , Humans , Amyotrophic Lateral Sclerosis/blood , Amyotrophic Lateral Sclerosis/diagnosis , Amyotrophic Lateral Sclerosis/pathology , Amyotrophic Lateral Sclerosis/genetics , tau Proteins/blood , tau Proteins/metabolism , Extracellular Vesicles/metabolism , Frontotemporal Dementia/blood , Frontotemporal Dementia/diagnosis , Frontotemporal Dementia/genetics , Frontotemporal Dementia/pathology , Biomarkers/blood , DNA-Binding Proteins/blood , DNA-Binding Proteins/genetics , Female , Male , Aged , Middle Aged , Supranuclear Palsy, Progressive/blood , Supranuclear Palsy, Progressive/diagnosis , Protein Isoforms/blood
4.
Molecules ; 29(8)2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38675584

ABSTRACT

To understand the biological relevance and mode of action of artificial protein ligands, crystal structures with their protein targets are essential. Here, we describe and investigate all known crystal structures that contain a so-called "molecular tweezer" or one of its derivatives with an attached natural ligand on the respective target protein. The aromatic ring system of these compounds is able to include lysine and arginine side chains, supported by one or two phosphate groups that are attached to the half-moon-shaped molecule. Due to their marked preference for basic amino acids and the fully reversible binding mode, molecular tweezers are able to counteract pathologic protein aggregation and are currently being developed as disease-modifying therapies against neurodegenerative diseases such as Alzheimer's and Parkinson's disease. We analyzed the corresponding crystal structures with 14-3-3 proteins in complex with mono- and diphosphate tweezers. Furthermore, we solved crystal structures of two different tweezer variants in complex with the enzyme Δ1-Pyrroline-5-carboxyl-dehydrogenase (P5CDH) and found that the tweezers are bound to a lysine and methionine side chain, respectively. The different binding modes and their implications for affinity and specificity are discussed, as well as the general problems in crystallizing protein complexes with artificial ligands.


Subject(s)
Protein Binding , Crystallography, X-Ray , Ligands , Humans , Models, Molecular , 14-3-3 Proteins/chemistry , 14-3-3 Proteins/metabolism , Binding Sites , Proteins/chemistry , Protein Conformation
5.
J Neurol ; 271(5): 2639-2648, 2024 May.
Article in English | MEDLINE | ID: mdl-38353748

ABSTRACT

BACKGROUND: Multiple system atrophy (MSA) is a complex and fatal neurodegenerative movement disorder. Understanding the comorbidities and drug therapy is crucial for MSA patients' safety and management. OBJECTIVES: To investigate the pattern of comorbidities and aspects of drug therapy in MSA patients. METHODS: Cross-sectional data of MSA patients according to Gilman et al. (2008) diagnostic criteria and control patients without neurodegenerative diseases (non-ND) were collected from German, multicenter cohorts. The prevalence of comorbidities according to WHO ICD-10 classification and drugs administered according to WHO ATC system were analyzed. Potential drug-drug interactions were identified using AiDKlinik®. RESULTS: The analysis included 254 MSA and 363 age- and sex-matched non-ND control patients. MSA patients exhibited a significantly higher burden of comorbidities, in particular diseases of the genitourinary system. Also, more medications were prescribed MSA patients, resulting in a higher prevalence of polypharmacy. Importantly, the risk of potential drug-drug interactions, including severe interactions and contraindicated combinations, was elevated in MSA patients. When comparing MSA-P and MSA-C subtypes, MSA-P patients suffered more frequently from diseases of the genitourinary system and diseases of the musculoskeletal system and connective tissue. CONCLUSIONS: MSA patients face a substantial burden of comorbidities, notably in the genitourinary system. This, coupled with increased polypharmacy and potential drug interactions, highlights the complexity of managing MSA patients. Clinicians should carefully consider these factors when devising treatment strategies for MSA patients.


Subject(s)
Comorbidity , Drug Interactions , Multiple System Atrophy , Polypharmacy , Humans , Multiple System Atrophy/epidemiology , Multiple System Atrophy/drug therapy , Cross-Sectional Studies , Male , Female , Aged , Middle Aged , Prevalence , Germany/epidemiology
6.
Brain Imaging Behav ; 18(1): 66-72, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37855956

ABSTRACT

Structural and functional changes in cortical and subcortical regions have been reported in behavioral variant frontotemporal dementia (bvFTD), however, a multimodal approach may provide deeper insights into the neural correlates of neuropsychiatric symptoms. In this multicenter study, we measured cortical thickness (CTh) and subcortical volumes to identify structural abnormalities in 37 bvFTD patients, and 37 age- and sex-matched healthy controls. For seed regions with significant structural changes, whole-brain functional connectivity (FC) was examined in a sub-cohort of N = 22 bvFTD and N = 22 matched control subjects to detect complementary alterations in brain network organization. To explore the functional significance of the observed structural and functional deviations, correlations with clinical and neuropsychological outcomes were tested where available. Significantly decreased CTh was observed in the bvFTD group in caudal middle frontal gyrus, left pars opercularis, bilateral superior frontal and bilateral middle temporal gyrus along with subcortical volume reductions in bilateral basal ganglia, thalamus, hippocampus, and amygdala. Resting-state functional magnetic resonance imaging showed decreased FC in bvFTD between: dorsal striatum and left caudal middle frontal gyrus; putamen and fronto-parietal regions; pallidum and cerebellum. Conversely, bvFTD showed increased FC between: left middle temporal gyrus and paracingulate gyrus; caudate nucleus and insula; amygdala and parahippocampal gyrus. Additionally, cortical thickness in caudal, lateral and superior frontal regions as well as caudate nucleus volume correlated negatively with apathy severity scores of the Neuropsychiatry Inventory Questionnaire. In conclusion, multimodal structural and functional imaging indicates that fronto-striatal regions have a considerable influence on the severity of apathy in bvFTD.


Subject(s)
Apathy , Frontotemporal Dementia , Humans , Frontotemporal Dementia/pathology , Magnetic Resonance Imaging/methods , Brain , Gray Matter/pathology
7.
Z Orthop Unfall ; 2023 Nov 15.
Article in English, German | MEDLINE | ID: mdl-37967830

ABSTRACT

Based on a systematic review, the present work analyses factors associated with the rerupture rate or non-healing after superior capsular reconstruction with autologous long biceps tendon in the reconstruction of the rotator cuff of the shoulder.A systematic review of the U.S. National Library of Medicine/National Institutes of Health (PubMed) database and the Cochrane Library was conducted in September 2021 using the PRISMA checklist. Articles were identified and analysed that contained data on the rerupture rate after superior capsular reconstruction with autologous long biceps tendon in reconstruction of the rotator cuff of the shoulder. The aim was to identify factors associated with rerupture or non-healing. The risk of bias was determined using the Newcastle-Ottawa scale.Primarily 86 hits could be generated. Seven articles from 2020 and 2021 met the inclusion criteria and were further analysed in terms of content. The evidence level was III to IV. Follow-up was between 12 (minimum) and 24 to 48 months. The risk of bias was not low. Factors that may be associated with rerupture or non-healing are diabetes mellitus and high-grade fatty degeneration of the subscapularis, infraspinatus, or teres minor as preoperative factors. Age, percent footprint coverage, tear size, symptom duration, number of bundles, acromioplasty performed, and tear configuration were not significant factors. Gender, degree of fatty degeneration of the supraspinatus and lesions of the subscapularis tendon were rated differently.According to the literature, but still currently with short-term observation periods, superior capsular reconstruction with an autologous long biceps tendon is another treatment option in the case of massive tears and elderly patients, if there is no high-grade fatty degeneration of the subscapularis, infraspinatus or teres minor. Diabetes mellitus has an unfavorable prognosis. Additional acromioplasty has so far not been associated with better outcomes.

8.
mBio ; : e0235723, 2023 Oct 24.
Article in English | MEDLINE | ID: mdl-37874130

ABSTRACT

During viral infections, type I interferons (IFN) are induced and play a key role in counteracting initial viral spread. Twelve different human IFNα subtypes exist that bind the same receptor; however, they elicit unique host responses and display distinct potencies of antiviral activities. Our previous studies on human immunodeficiency virus (HIV) and hepatitis B virus (HBV) demonstrated that the clinically used IFNα2 is not the most effective one among the IFNα subtypes. By sequence modeling, we identified a region in helix B with mainly conserved residues at the outside facing IFNAR1, but variable residues at the inside facing the core of IFNα, potentially representing a putative tunable anchor to tune pleiotropic IFN responses. Using site-directed mutagenesis, various mutations were introduced into the IFNα2b backbone targeting sites which are important for binding to IFNAR1 and IFNAR2, the putative tunable anchor, or outside these three regions. Selected mutations were based on sequence differences to high antiviral subtypes IFNα6 and IFNα14. Treatment assays against HBV and HIV identified several critical residues for the antiviral activity of IFNα mainly in the IFNAR1 binding region. Combined mutations of the IFNα2 IFNAR1/2 binding sites or the IFNAR1 binding region plus the putative tunable anchor by those of IFNα14 further augmented activation of different downstream signaling cascades providing a molecular correlate for the enhanced antiviral activity. We describe here important functional residues within IFNα subtype molecules, which enabled us to design novel and innovative drugs that may have the potential to be used in clinical trials against a variety of different viral infections.IMPORTANCEThe potency of interferon (IFN)α to restrict viruses was already discovered in 1957. However, until today, only IFNα2 out of the 12 distinct human IFNα subtypes has been therapeutically used against chronic viral infections. There is convincing evidence that other IFNα subtypes are far more efficient than IFNα2 against many viruses. In order to identify critical antiviral residues within the IFNα subtype sequence, we designed hybrid molecules based on the IFNα2 backbone with individual sequence motifs from the more potent subtypes IFNα6 and IFNα14. In different antiviral assays with HIV or HBV, residues binding to IFNAR1 as well as combinations of residues in the IFNAR1 binding region, the putative tunable anchor, and residues outside these regions were identified to be crucial for the antiviral activity of IFNα. Thus, we designed artificial IFNα molecules, based on the clinically approved IFNα2 backbone, but with highly improved antiviral activity against several viruses.

9.
PLoS One ; 18(8): e0289827, 2023.
Article in English | MEDLINE | ID: mdl-37556416

ABSTRACT

The aim of this study was to determine the effect of oclacitinib (Apoquel) on development of surgical site infections in canines following clean orthopedic stifle surgery. Medical records of dogs undergoing unilateral, clean orthopedic stifle procedures were retrospectively examined for development of post-operative surgical site infections. Data collected for statistical analysis included age, sex, body weight, current medications, anesthesia and surgery times, white blood cell count, and neutrophil count. Surgical site infections were identified in 8.7% (34/390) of stifle procedures- 8.0% (29/364) in dogs not treated with oclacitinib and 19.2% (5/26) in dogs treated with oclacitinib (p = 0.053). There was a significant difference in development of surgical site infection in dogs with longer anesthesia times (p = 0.003) and higher body weights (p = 0.037). Dogs being treated with oclacitinib at the time of clean, orthopedic stifle surgery did not have a significantly higher incidence of surgical site infections. However, client education regarding risk of infection and increased patient monitoring post-operatively are recommended, especially in patients with increased body weight or longer anesthetic times.


Subject(s)
Dog Diseases , Surgical Wound Infection , Dogs , Animals , Surgical Wound Infection/drug therapy , Surgical Wound Infection/prevention & control , Retrospective Studies , Stifle , Dog Diseases/drug therapy , Body Weight
10.
Int J Mol Sci ; 24(13)2023 Jun 26.
Article in English | MEDLINE | ID: mdl-37445853

ABSTRACT

Inclusion body myositis (IBM) is a chronic, mostly treatment-resistant, inflammatory myopathy with a pathology that centers around specific interactions between inflammation and protein accumulation. The study aimed to identify the inflammasome as a key event in the complex network of pathomechanisms. Regulation of the inflammasome was assessed in a well-established pro-inflammatory cell culture model using human myoblasts and primary human myotubes. By quantitative PCR, western blot and immunocytochemistry, inflammasome markers including NLRP3 were assessed in muscle cells exposed to the cytokines IL-1ß and IFN-γ. The data were corroborated by analysis of muscle biopsies from patients with IBM compared to other myositis subtypes. In the cell culture model of IBM, the NLRP3 inflammasome was significantly overexpressed, as evidenced by western blot (p = 0.03) and quantitative PCR (p < 0.01). Target genes that play a role in inflammasome assembly, T-cell migration, and MHC-I expression (p = 0.009) were highly co-upregulated. NLRP3 was significantly overexpressed in muscle biopsies from IBM samples compared to disease controls (p = 0.049), including other inflammatory myopathies. Due to the extraordinary features of the pathogenesis and the pronounced upregulation of NLRP3 in IBM, the inflammasome could serve as a key molecule that drives the inflammatory cascade as well as protein accumulation in the muscle. These data can be useful for future therapeutic developments.


Subject(s)
Myositis, Inclusion Body , Myositis , Humans , Myositis, Inclusion Body/metabolism , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Cells, Cultured , Muscle, Skeletal/metabolism , Myositis/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism
11.
Angew Chem Int Ed Engl ; 62(35): e202308238, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37439487

ABSTRACT

Herein, we report a methodology to access isotopically labeled esters and amides from carbonates and carbamates employing an oxygen deletion strategy. This methodology utilizes a decarboxylative carbonylation approach for isotope labeling with near stoichiometric, ex situ generated 12 C, or 13 C carbon monoxide. This reaction is characterized by its broad scope, functional group tolerance, and high yields, which is showcased with the synthesis of structurally complex molecules. A complementary method that operates by the catalytic in situ generation of CO via the reduction of CO2 liberated during decarboxylation has also been developed as a proof-of-concept approach that CO2 -derived compounds can be converted to CO-containing frameworks. Mechanistic studies provide insight into the catalytic steps which highlight the impact of ligand choice to overcome challenges associated with low-pressure carbonylation methodologies, along with rational for the development of future methodologies.

12.
J Bone Miner Metab ; 41(6): 741-751, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37407738

ABSTRACT

INTRODUCTION: The selective androgen receptor modulator ligandrol (LGD-4033 or VK5211) has been shown to improve muscle tissue. In the present study, the effect of ligandrol on bone tissue was investigated in ovariectomized rat model. MATERIALS AND METHODS: Three-month-old Sprague Dawley rats were either ovariectomized (OVX, n = 60) or left intact (NON-OVX, n = 15). After 9 weeks, OVX rats were divided into four groups: untreated OVX (n = 15) group and three OVX groups (each of 15 rats) treated with ligandrol orally at doses of 0.03, 0.3, or 3 mg/kg body weight. After five weeks, lumbar vertebral bodies (L), tibiae, and femora were examined using micro-computed tomographical, biomechanical, ashing, and gene expression analyses. RESULTS: In the 3-mg ligandrol group, bone structural properties were improved (trabecular number: 38 ± 8 vs. 35 ± 7 (femur), 26 ± 7 vs. 22 ± 6 (L), 12 ± 5 vs. 6 ± 3 (tibia) and serum phosphorus levels (1.81 ± 0.17 vs.1.41 ± 0.17 mmol/l), uterus (0.43 ± 0.04 vs. 0.11 ± 0.02 g), and heart (1.13 ± 0.11 vs. 1.01 ± 0.08 g) weights were increased compared to the OVX group. Biomechanical parameters were not changed. Low and medium doses did not affect bone tissue and had fewer side effects. Body weight and food intake were not affected by ligandrol; OVX led to an increase in these parameters and worsened all bone parameters. CONCLUSION: Ligandrol at high dose showed a subtle anabolic effect on structural properties without any improvement in biomechanical properties of osteoporotic bones. Considering side effects of ligandrol at this dose, its further investigation for the therapy of postmenopausal osteoporosis should be reevaluated.


Subject(s)
Osteoporosis , Receptors, Androgen , Female , Humans , Rats , Animals , Rats, Sprague-Dawley , Bone Density , Osteoporosis/drug therapy , Osteoporosis/metabolism , Body Weight , Androgens , Ovariectomy
13.
J Clin Med ; 12(10)2023 May 15.
Article in English | MEDLINE | ID: mdl-37240572

ABSTRACT

The aim of this study is to determine the critical time intervals and influencing covariates for in-hospital mortality in geriatric trauma and orthopedic patients. During a period of five years, we retrospectively review patients aged > 60 years who were hospitalized at the Department of Trauma, Orthopedic, and Plastic Surgery. The primary outcome is the mean time to death. Survival analysis is performed using an accelerated failure time model. A total of 5388 patients are included in the analysis. Two-thirds underwent surgery (n = 3497, 65%) and one-third were conservatively treated (n = 1891, 35%). The in-hospital mortality rate is 3.1% (n = 168; surgery, n = 112; conservative, n = 56). The mean time to death is 23.3 days (±18.8) after admission in the surgery group and 11.3 days (±12.5) in the conservative treatment group. The greatest accelerating effect on mortality is found in the intensive care unit (16.52, p < 0.001). We are able to identify a critical time interval for in-hospital mortality between days 11 and 23. The day of death on weekend days/holidays, hospitalization for conservative treatment, and treatment at the intensive care unit significantly increase the risk of in-hospital mortality. Early mobilization and a short hospitalization duration seem to be of major importance in fragile patients.

14.
JACS Au ; 3(3): 756-761, 2023 Mar 27.
Article in English | MEDLINE | ID: mdl-37006775

ABSTRACT

Herein, we report a strategy for the formation of isotopically labeled carboxylic esters from boronic esters/acids using a readily accessible palladium carboxylate complex as an organometallic source of isotopically labeled functional groups. The reaction allows access to either unlabeled or full 13C- or 14C-isotopically labeled carboxylic esters, and the method is characterized by its operational simplicity, mild conditions, and general substrate scope. Our protocol is further extended to a carbon isotope replacement strategy, involving an initial decarbonylative borylation procedure. Such an approach allows access to isotopically labeled compounds directly from the unlabeled pharmaceutical, which can have implications for drug discovery programs.

15.
Front Med (Lausanne) ; 10: 1108543, 2023.
Article in English | MEDLINE | ID: mdl-37035318

ABSTRACT

Introduction: The Hepatitis Delta Virus (HDV) is a defective, single-stranded RNA virusoid encoding for a single protein, the Hepatitis Delta Antigen (HDAg), which requires the hepatitis B virus (HBV) envelope protein (HBsAg) for its transmission. Currently, hepatitis D is the most aggressive form of viral hepatitis and treatment options are limited. Worldwide 12 million people are chronically infected with HDV being at high risk for progression to cirrhosis and development of liver cancer. Objectives: Although it is well established that Mongolia is the country with the highest prevalence of HDV infections, the information on the molecular epidemiology and factors contributing to HDV sequence diversity are largely unclear. The aim of the study was to characterize the sequence diversity of HDV in rural areas from Mongolia and to determine the extent of HLA class I-associated selection pressure. Patients and methods: From the HepMongolia cohort from rural areas in Mongolia, 451 HBsAg-positive individuals were selected and anti-HDV, HDV-RNA and the sequence of the large HDAg was determined. For all individuals the HLA class I locus was genotyped. Residues under selection pressure in the presence of individual HLA class I types were identified with the recently published analysis tool HAMdetector. Results: Of 431 HBsAg positive patients, 281 were anti-HDV positive (65%), and HDV-RNA could be detected in 207 of 281 (74%) of patients. The complete large HDAg was successfully sequenced from 131 samples. Phylogenetic analysis revealed that all Mongolian HDV isolates belong to genotype 1, however, they separate into several different clusters without clear regional association. In turn, from phylogeny there is strong evidence for recent local transmission events. Importantly, we found multiple residues with strong support for HLA class I-associated selection pressure consistent with a functional CD8+ T cell response directed against HDV. Conclusion: HDV isolates from Mongolia are highly diverse. The molecular epidemiology suggests circulation of multiple subtypes and provides evidence for ongoing recent transmissions.

16.
Nat Commun ; 14(1): 758, 2023 02 10.
Article in English | MEDLINE | ID: mdl-36765094

ABSTRACT

Cellular differentiation is directly determined by concentration gradients of morphogens. As a central model for gradient formation during development, Hedgehog (Hh) morphogens spread away from their source to direct growth and pattern formation in Drosophila wing and eye discs. What is not known is how extracellular Hh spread is achieved and how it translates into precise gradients. Here we show that two separate binding areas located on opposite sides of the Hh molecule can interact directly and simultaneously with two heparan sulfate (HS) chains to temporarily cross-link the chains. Mutated Hh lacking one fully functional binding site still binds HS but shows reduced HS cross-linking. This, in turn, impairs Hhs ability to switch between both chains in vitro and results in striking Hh gradient hypomorphs in vivo. The speed and propensity of direct Hh switching between HS therefore shapes the Hh gradient, revealing a scalable design principle in morphogen-patterned tissues.


Subject(s)
Drosophila Proteins , Animals , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Heparitin Sulfate/metabolism , Drosophila/metabolism , Binding Sites , Drosophila melanogaster/metabolism , Wings, Animal
17.
Clin. biomed. res ; 43(1): 58-68, 2023.
Article in English | LILACS | ID: biblio-1435960

ABSTRACT

Hemophilia is an inherited X-linked coagulopathy defined by a deficiency or abnormality in the clotting function of factor VIII (Hemophilia A) or factor IX (Hemophilia B). Prophylaxis ­ the regular administration of therapeutic products to maintain hemostasis and prevent bleeding ­ is the mainstream of treatment. Addressing the development and scientific evidence for administrating prophylaxis is the goal of this review. Prophylaxis is the therapeutic modality of choice for people with severe hemophilia, being considered, in principle, a lifelong treatment. It should have an early onset, ideally as a primary, or at least secondary. Even lifelong tertiary prophylaxis seems to offer benefit, although further studies are still lacking. Individualized strategies should lead to an optimization of the dilemma between better joint outcomes versus involved costs.


Subject(s)
Humans , Male , Female , Factor VIII/therapeutic use , Hemophilia B/prevention & control , Hemophilia A/prevention & control
18.
Clin. biomed. res ; 43(1): 69-74, 2023.
Article in English | LILACS | ID: biblio-1435967

ABSTRACT

The history of hemophilia is ancient, with descriptions dated to the 2nd century AD. The first modern narratives appeared in 1800s, when total blood transfusion was the only available treatment and life expectancy was remarkably low. Advances occurred with the use of plasma and cryoprecipitate, but only the discovered of factor concentrates revolutionized the treatment. The implantation of prophylaxis allowed hemophilic patients to prevent bleeding and the development of chronic arthropathy, although with a significant burdensome with the regular infusions. In the past 20 years, this field has witnessed major improvements, including the development of gene therapy and other pharmacological approaches.


Subject(s)
Humans , History, 19th Century , History, 20th Century , History, 21st Century , Factor IX/history , Factor VIII/history , Hemophilia B/history , Hemophilia A/history , Hemophilia B/therapy , Hemophilia A/therapy
19.
RSC Adv ; 12(53): 34176-34184, 2022 Nov 29.
Article in English | MEDLINE | ID: mdl-36545626

ABSTRACT

Therapy resistance remains a challenge for the clinics. Here, dual-active chemicals that simultaneously inhibit independent functions in disease-relevant proteins are desired though highly challenging. As a model, we here addressed the unique protease threonine aspartase 1, involved in various cancers. We hypothesized that targeting basic residues in its bipartite nuclear localization signal (NLS) by precise bisphosphate ligands inhibits additional steps required for protease activity. We report the bisphosphate anionic bivalent inhibitor 11d, selectively binding to the basic NLS cluster (220KKRR223) with high affinity (K D = 300 nM), thereby disrupting its interaction and function with Importin α (IC50 = 6 µM). Cell-free assays revealed that 11d additionally affected the protease's catalytic substrate trans-cleavage activity. Importantly, functional assays comprehensively demonstrated that 11d inhibited threonine aspartase 1 also in living tumor cells. We demonstrate for the first time that intracellular interference with independent key functions in a disease-relevant protein by an inhibitor binding to a single site is possible.

20.
Int J Mol Sci ; 23(23)2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36498882

ABSTRACT

Objective markers for the neurodegenerative disorder progressive supranuclear palsy (PSP) are needed to provide a timely diagnosis with greater certainty. Non-coding RNA (ncRNA), including microRNA, piwi-interacting RNA, and transfer RNA, are good candidate markers in other neurodegenerative diseases, but have not been investigated in PSP. Therefore, as proof of principle, we sought to identify whether they were dysregulated in matched serum and cerebrospinal fluid (CSF) samples of patients with PSP. Small RNA-seq was undertaken on serum and CSF samples from healthy controls (n = 20) and patients with PSP (n = 31) in two cohorts, with reverse transcription-quantitative PCR (RT-qPCR) to confirm their dysregulation. Using RT-qPCR, we found in serum significant down-regulation in hsa-miR-92a-3p, hsa-miR-626, hsa-piR-31068, and tRNA-ValCAC. In CSF, both hsa-let-7a-5p and hsa-piR-31068 showed significant up-regulation, consistent with their changes observed in the RNA-seq results. Interestingly, we saw no correlation in the expression of hsa-piR-31068 within our matched serum and CSF samples, suggesting there is no common dysregulatory mechanism between the two biofluids. While these changes were in a small cohort of samples, we have provided novel evidence that ncRNA in biofluids could be possible diagnostic biomarkers for PSP and further work will help to expand this potential.


Subject(s)
MicroRNAs , Supranuclear Palsy, Progressive , Humans , Supranuclear Palsy, Progressive/diagnosis , Supranuclear Palsy, Progressive/genetics , Biomarkers , MicroRNAs/genetics , Down-Regulation
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