We report the first total synthesis of the natural product selaginpulvilin X, a selaginellaceae polyphenol class of compounds. Our synthetic strategy employs cross-coupling reactions and an organolithium addition to construct the carbon framework. Subsequently, the functional group modifications and deprotection yield the natural product. Spectral analysis confirms the proposed structure by comparing natural and synthetic samples.
- Publication type
- Journal Article MeSH
AIM: To propose a standardized, high-resolution ultrasound (US) protocol to assess the patellar tendon-Hoffa fat pad interface (PTHFPI) in patients with (proximal) patellar tendinopathy (PPT). METHODS: Using a high-frequency transducer and a high-level machine, we matched the cadaveric and histological microarchitecture of the PTHFPI with multiple sonographic patterns of patients with PPT. Likewise, high-sensitive color/power Doppler assessments were also performed to evaluate the microcirculation of the soft tissues beneath the patellar tendon. RESULTS: Modern US equipment allows for detailed assessment of the potential pain generators located inside the PTHFPI in patients with PPT. They include anterosuperior portion of the Hoffa body and the loose connective tissue of the deep paratenon with its microvascular plexus. CONCLUSIONS: In patients with PPT, accurate sonographic assessment of the PTHFPI can be performed using adequate technological equipment. Accordingly, tailored ultrasound-guided interventions can also be planned if/when clinically indicated.
- MeSH
- Knee Joint diagnostic imaging MeSH
- Middle Aged MeSH
- Humans MeSH
- Patellar Ligament * diagnostic imaging MeSH
- Cadaver MeSH
- Aged MeSH
- Tendinopathy * diagnostic imaging pathology MeSH
- Adipose Tissue * diagnostic imaging MeSH
- Ultrasonography methods MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Bordetella pertussis is the causative agent of whooping cough in humans, a disease that has recently experienced a resurgence. In contrast, Bordetella bronchiseptica infects the respiratory tract of various mammalian species, causing a range of symptoms from asymptomatic chronic carriage to acute illness. Both pathogens utilize type III secretion system (T3SS) to deliver the effector protein BteA into host cells. Once injected, BteA triggers a cascade of events leading to caspase 1-independent necrosis through a mechanism that remains incompletely understood. We demonstrate that BteA-induced cell death is characterized by the fragmentation of the cellular endoplasmic reticulum and mitochondria, the formation of necrotic balloon-like protrusions, and plasma membrane permeabilization. Importantly, genome-wide CRISPR-Cas9 screen targeting 19,050 genes failed to identify any host factors required for BteA cytotoxicity, suggesting that BteA does not require a single nonessential host factor for its cytotoxicity. We further reveal that BteA triggers a rapid and sustained influx of calcium ions, which is associated with organelle fragmentation and plasma membrane permeabilization. The sustained elevation of cytosolic Ca2+ levels results in mitochondrial calcium overload, mitochondrial swelling, cristolysis, and loss of mitochondrial membrane potential. Inhibition of calcium channels with 2-APB delays both the Ca2+ influx and BteA-induced cell death. Our findings indicate that BteA exploits essential host processes and/or redundant pathways to disrupt calcium homeostasis and mitochondrial function, ultimately leading to host cell death.IMPORTANCEThe respiratory pathogens Bordetella pertussis and Bordetella bronchiseptica exhibit cytotoxicity toward a variety of mammalian cells, which depends on the type III secretion effector BteA. Moreover, the increased virulence of B. bronchiseptica is associated with enhanced expression of T3SS and BteA. However, the molecular mechanism underlying BteA cytotoxicity is elusive. In this study, we performed a CRISPR-Cas9 screen, revealing that BteA-induced cell death depends on essential or redundant host processes. Additionally, we demonstrate that BteA disrupts calcium homeostasis, which leads to mitochondrial dysfunction and cell death. These findings contribute to closing the gap in our understanding of the signaling cascades targeted by BteA.
- MeSH
- Bacterial Proteins * metabolism genetics MeSH
- Bordetella bronchiseptica genetics metabolism drug effects MeSH
- Bordetella pertussis genetics pathogenicity metabolism drug effects MeSH
- Cell Death * drug effects MeSH
- Endoplasmic Reticulum metabolism drug effects MeSH
- Homeostasis * MeSH
- Host-Pathogen Interactions MeSH
- Humans MeSH
- Mitochondria metabolism drug effects MeSH
- Type III Secretion Systems metabolism genetics MeSH
- Calcium * metabolism MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
N6-Methyladenosine (m6A) is the predominant internal RNA modification in eukaryotic messenger RNAs (mRNAs) and plays a crucial role in mRNA stability. Here, using human cells, we reveal that m6A sites in the coding sequence (CDS) trigger CDS-m6A decay (CMD), a pathway that is distinct from previously reported m6A-dependent degradation mechanisms. Importantly, CDS m6A sites act considerably faster and more efficiently than those in the 3' untranslated region, which to date have been considered the main effectors. Mechanistically, CMD depends on translation, whereby m6A deposition in the CDS triggers ribosome pausing and transcript destabilization. The subsequent decay involves the translocation of the CMD target transcripts to processing bodies (P-bodies) and recruitment of the m6A reader protein YT521-B homology domain family protein 2 (YTHDF2). Our findings highlight CMD as a previously unknown pathway, which is particularly important for controlling the expression of developmental regulators and retrogenes.
- MeSH
- 3' Untranslated Regions MeSH
- Adenosine * analogs & derivatives metabolism genetics MeSH
- HEK293 Cells MeSH
- HeLa Cells MeSH
- Humans MeSH
- RNA, Messenger * genetics metabolism MeSH
- Open Reading Frames * MeSH
- RNA-Binding Proteins * genetics metabolism MeSH
- Protein Biosynthesis * MeSH
- Ribosomes metabolism genetics MeSH
- RNA Stability * MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Acute cellular rejection (ACR) frequently occurs following lung transplantation (LuTx) and represents a risk factor for the development of chronic lung allograft dysfunction (CLAD) as well as long-term survival. The histopathological diagnosis of ACR carries a burden of interobserver variability. The widespread utilization and cost-effectiveness of immunohistochemistry (IHC) was proven beneficial in diagnosing rejection in human kidney transplantations and LuTx rat models. However, its potential for ACR detection in patients remains unexplored. We analyzed surface markers (CD3, CD4, CD8, CD20, CD68, CD47, PD-1, PD-L1, and CD31/PECAM-1) on lung tissue cryobiopsy samples collected within 6 months post-LuTx from 60 LuTx recipients, 48 of whom were diagnosed with ACR. Additionally, serum samples from 51 patients were analyzed using a multiplex bead-based Luminex assay. The cytokines and markers included PD-L1, IL2, TNFα, IFNγ, and Granzyme B. We observed a significant increase in PD-L1 tissue expression within the rejection group, suggesting a concerted effort to suppress immune responses, especially those mediated by T-cells. Furthermore, we noted significant differences in PECAM-1 levels between ACR/non-ACR. Additionally, peripheral blood C-reactive-protein levels tended to be higher in the ACR group, while Luminex serum analyses did not reveal any significant differences between groups. In conclusion, our findings suggest the potential value of PECAM-1 and PD-L1 markers in diagnosing ACR.
- MeSH
- Acute Disease MeSH
- B7-H1 Antigen * metabolism blood MeSH
- Platelet Endothelial Cell Adhesion Molecule-1 * metabolism MeSH
- Biomarkers * blood metabolism MeSH
- Adult MeSH
- Immunohistochemistry MeSH
- Middle Aged MeSH
- Humans MeSH
- Lung pathology MeSH
- Graft Rejection * diagnosis blood MeSH
- Aged MeSH
- Lung Transplantation * adverse effects MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
INTRODUCTION AND OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters the nasal cavity, penetrates the nasal epithelial cells through the interaction of its spike protein with the host cell receptor angiotensin-converting enzyme 2 (ACE2) and then triggers a cytokine storm. We aimed to assess the biocompatibility of fullerenol nanoparticles C60(OH)40 and ectoine, and to document their effect on the protection of primary human nasal epithelial cells (HNEpCs) against the effects of interaction with the fragment of virus - spike protein. This preliminary research is the first step towards the construction of a intranasal medical device with a protective, mechanical function against SARS-CoV-2 similar to that of personal protective equipment (eg masks). METHODS: We used HNEpCs and the full-length spike protein from SARS-CoV-2 to mimic the first stage of virus infection. We assessed cell viability with the XTT assay and a spectrophotometer. May-Grünwald Giemsa and periodic acid-Schiff staining served to evaluate HNEpC morphology. We assessed reactive oxygen species (ROS) production by using 2',7'-dichlorofluorescin diacetate and commercial kit. Finally, we employed reverse transcription polymerase chain reaction, Western blotting and confocal microscopy to determine the expression of angiotensin-converting enzyme 2 (ACE2) and inflammatory cytokines. RESULTS: There was normal morphology and unchanged viability of HNEpCs after incubation with 10 mg/L C60(OH)40, 0.2% ectoine or their composite for 24 h. The spike protein exerted cytotoxicity via ROS production. Preincubation with the composite protected HNEpCs against the interaction between the spike protein and the host membrane and prevented the production of key cytokines characteristic of severe coronavirus disease 2019, including interleukin 6 and 8, monocyte chemotactic protein 1 and 2, tissue inhibitor of metalloproteinases 2 and macrophage colony-stimulating factor. CONCLUSION: In the future, the combination of fullerenol and ectoine may be used to prevent viral infections as an intranasal medical device for people with reduced immunity and damaged mucous membrane.
- MeSH
- Amino Acids, Diamino MeSH
- Angiotensin-Converting Enzyme 2 metabolism MeSH
- COVID-19 * prevention & control MeSH
- Cytokines metabolism MeSH
- Epithelial Cells * drug effects virology MeSH
- Fullerenes * pharmacology chemistry MeSH
- Spike Glycoprotein, Coronavirus * metabolism MeSH
- Cells, Cultured MeSH
- Humans MeSH
- Nanoparticles * chemistry MeSH
- Nasal Mucosa drug effects cytology MeSH
- Reactive Oxygen Species metabolism MeSH
- SARS-CoV-2 * drug effects MeSH
- Cytokine Release Syndrome * prevention & control MeSH
- Cell Survival * drug effects MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Age-related macular degeneration (AMD) is a progressive chronic disease causing visual impairment or central vision loss in the elderly. We hypothesized that successful rheopheresis would be associated with positive changes in soluble endoglin (sENG), PSCK9, alpha-2-macroglobulin (A2M), and hs-CRP levels. 31 elderly patients with the dry form of AMD, treated with rheopheresis with a follow-up period of at least 5 years and an average age of 68 ± 4 years, were evaluated. Each treated patient received a series of 8 procedures in 10 weeks and, after the 2-year period, another 2 procedures within 1 week. Then, the patients were followed up every 6 months and divided into the successfully treated and therapeutic failure group according to best-corrected visual acuity (BCVA), size of the drusen area, and the drusenoid pigment epithelium detachment (DPED). Based on the ophthalmological assessment, rheopheresis treatment was successful in 73% of AMD patients. The therapy was associated with a significant decrease in total cholesterol, LDL-C, HDL-C, apoprotein B, lipoprotein (a) levels, and rheologically important parameters, irrespective of the therapy's success or failure. The success of rheopheresis therapy was exclusively related to a significant decrease in sENG and A2M levels. Over the long term, rheopheresis prevented the decline of BCVA, reduced the DPED and area of macular drusen, and improved the preservation of an intact photoreceptor ellipsoid zone in most patients. Moreover, we showed for the first time that sENG and A2M could be potentially sensitive biomarkers of successful rheopheresis procedure, irrespective of lipid parameters changes.
- MeSH
- Biomarkers * blood MeSH
- Endoglin * blood MeSH
- Middle Aged MeSH
- Humans MeSH
- Macular Degeneration * therapy blood MeSH
- Aged MeSH
- Treatment Outcome MeSH
- Visual Acuity MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
High-risk human papillomaviruses (HPVs) cause various cancers. While type-specific prophylactic vaccines are available, additional anti-viral strategies are highly desirable. Initial HPV cell entry involves receptor-switching induced by structural capsid modifications. These modifications are initiated by interactions with cellular heparan sulphates (HS), however, their molecular nature and functional consequences remain elusive. Combining virological assays with hydrogen/deuterium exchange mass spectrometry, and atomic force microscopy, we investigate the effect of capsid-HS binding and structural activation. We show how HS-induced structural activation requires a minimal HS-chain length and simultaneous engagement of several binding sites by a single HS molecule. This engagement introduces a pincer-like force that stabilizes the capsid in a conformation with extended capsomer linkers. It results in capsid enlargement and softening, thereby likely facilitating L1 proteolytic cleavage and subsequent L2-externalization, as needed for cell entry. Our data supports the further devising of prophylactic strategies against HPV infections.
- MeSH
- Heparitin Sulfate * metabolism chemistry MeSH
- Papillomavirus Infections virology MeSH
- Virus Internalization * MeSH
- Capsid * metabolism chemistry MeSH
- Humans MeSH
- Human Papillomavirus Viruses MeSH
- Human papillomavirus 16 metabolism physiology MeSH
- Microscopy, Atomic Force * MeSH
- Papillomaviridae physiology MeSH
- Polysaccharides metabolism chemistry MeSH
- Protein Binding MeSH
- Binding Sites MeSH
- Capsid Proteins * metabolism chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
