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ObjectivesFarnesyltransferase inhibitors (FTI), which inhibit the prenylation of Ras GTPases, were developed as anti-cancer drugs. As additional target proteins for prenylation were identified in the past, it is likely that FTI have potential value for therapeutic purposes beyond cancer. The effect of FTI on B-cells remains unclear. To address this issue, we investigated the effects of in vitro FTI treatment on effector and regulatory B-cells in healthy controls and renal transplant patients.MethodsFor this purpose, B-cells were isolated from the peripheral blood of healthy controls and renal transplant patients. Purified B-cells were stimulated via Toll-like-receptor 9 (TLR-9) in the presence or absence of FTI. Regulatory functions, such as IL-10 and Granzyme B (GrB) secretion, were assessed by flow cytometry. In addition, effector B-cell functions, such as plasma cell formation and IgG secretion, were studied.ResultsThe two FTI Lonafarnib and tipifarnib both suppressed TLR-9-induced B-cell proliferation. Maturation of IL-10 producing B-cells was suppressed by FTI at high concentrations as well as induction of GrB-secreting B-cells. Plasma blast formation and IgG secretion were potently suppressed by FTI. Moreover, purified B-cells from immunosuppressed renal transplant patients were also susceptible to FTI-induced suppression of effector functions, evidenced by diminished IgG secretion.ConclusionFTI suppress in vitro B-cell proliferation and plasma cell formation while partially preserving IL-10 as well as GrB production of B-cells. Thus, FTI may have immunosuppressive capacity encouraging further studies to investigate the potential immunomodulatory value of this agent.

Prenyltransferases (PTases) are known to play a role in embryonic development, normal tissue homeostasis and cancer by posttranslationally modifying proteins involved in these processes. They are being discussed as potential drug targets in an increasing number of diseases, ranging from Alzheimer's disease to malaria. Protein prenylation and the development of specific PTase inhibitors (PTIs) have been subject to intense research in recent decades. Recently, the FDA approved lonafarnib, a specific farnesyltransferase inhibitor that acts directly on protein prenylation; and bempedoic acid, an ATP citrate lyase inhibitor that might alter intracellular isoprenoid composition, the relative concentrations of which can exert a decisive influence on protein prenylation. Both drugs represent the first approved agent in their respective substance class. Furthermore, an overwhelming number of processes and proteins that regulate protein prenylation have been identified over the years, many of which have been proposed as molecular targets for pharmacotherapy in their own right. However, certain aspects of protein prenylation, such as the regulation of PTase gene expression or the modulation of PTase activity by phosphorylation, have attracted less attention, despite their reported influence on tumor cell proliferation. Here, we want to summarize the advances regarding our understanding of the regulation of protein prenylation and the potential implications for drug development. Additionally, we want to suggest new lines of investigation that encompass the search for regulatory elements for PTases, especially at the genetic and epigenetic levels.

Context. ESO 141-G55 is a nearby X-ray bright broad-line Seyfert 1 (BLS1) that has been classified as a bare active galactic nucleus (AGN) due to a lack of warm absorption along its line of sight, providing an unhampered view into its disc-corona system. Aims. We aim to probe its disc-corona system thanks to the first simultaneous XMM-Newton and NuSTAR observation obtained October 1–2, 2022. Methods. We carried out an X-ray broadband spectral analysis to determine the dominant process(es) at work as well as a spectral energy distribution (SED) analysis to determine the disc-corona properties. Results. The simultaneous broadband X-ray spectrum of ESO 141-G55 is characterised by the presence of a prominent smooth soft X-ray excess, a broad Fe Kα emission line, and a significant Compton hump. The high-resolution reflection grating spectrometer spectra confirmed the lack of intrinsic warm-absorbing gas along our line of sight in the AGN rest frame, verifying that it is still in a bare state. However, soft X-ray emission lines were observed, indicating substantial warm gas out of our line of sight. The intermediate inclination of the disc-corona system (∼43°) may offer us a favourable configuration to observe ultra-fast outflows from the disc, but none were found in this 2022 observation, contrary to a previous 2007 XMM-Newton one. We ruled out relativistic reflection alone on a standard disc based on the X-ray broadband analysis, while a combination of soft and hard Comptonisation by a warm and hot corona (RELAGN) plus relativistic reflection (REFLKERRD) reproduces the ESO 141-G55 SED quite well. The hot corona temperature is very hot, ∼140 keV, and much higher than about 80% of AGNs, whereas the warm corona temperature, ∼0.3 keV, is similar to the values found in other sub-Eddington AGNs. ESO 141-G55 is accreting at a moderate Eddington accretion rate (∼10–20%). Conclusions. Our analysis points to a significant contribution of an optically thick warm corona to both the soft X-ray and UV emission in ESO 141-G55, adding to the growing evidence that the accretion of AGNs (even at a moderate accretion rate) appears to deviate from standard disc theory. [ABSTRACT FROM AUTHOR]

Objective: To investigate pelvic floor dysfunction (PFD; urinary incontinence (UI), faecal incontinence (FI) and prolapse) ≥20 years after childbirth and their association with delivery mode history and demographic characteristics. Design: Cohort study with long‐term follow‐up. Setting: Maternity units in Aberdeen and Birmingham (UK) and Dunedin (NZ). Population: Women giving birth in 1993/1994. Methods: Postal questionnaires at 20 (New Zealand) or 26 (United Kingdom) years after index birth (n = 6195). Regression analyses investigated associations between risk factors and UI, FI and prolapse symptoms. Main Outcome Measures: Prevalence of self‐reported UI, FI, 'something coming down' from or in the vagina (SCD), and the Pelvic Organ Prolapse‐Symptom Score, and relationships with delivery method. Results: Thirty‐seven per cent (n = 2270) responded at 20/26 years, of whom 61% reported UI (59% of whom reported more severe UI), 22% FI and 17% prolapse symptoms. Having only caesarean section (CS) was associated with a significantly lower risk of UI (OR 0.63, 95% CI 0.46–0.85), FI (OR 0.63, 95% CI 0.42–0.96) and SCD (OR 0.44, 95% CI 0.27–0.74) compared to only spontaneous vaginal deliveries (SVDs). Having any forceps delivery was associated with reporting FI compared to only SVDs (OR 1.29, 95% CI 1.00–1.66), but there was no association for UI (OR 0.95, 95% CI 0.76–1.19) or SCD (OR 1.05, 95% CI 0.80–1.38). Higher current BMI was associated with all PFD outcomes. Conclusions: Prevalence of PFD continues to increase up to 26 years following index birth, and differences were observed according to delivery mode history. Exclusive CS was associated with less risk of UI, FI and any prolapse symptoms. [ABSTRACT FROM AUTHOR]

Introduction: During the first lockdown of the COVID-19 pandemic, several medical students volunteered as assistants in hospitals, public health departments, and other healthcare services to support and substitute permanent staff. The underlying motivations to help are unclear. Therefore, we aimed to assess medical students' motivations and influencing variables such as perceived stress and burden, compassion, and indicators of spirituality.Materials and Methods: Cross-sectional survey (convenience sample) from May to June 2020, directly after the first lockdown, among medical students with standardized instruments. One of them is the 12-item Motivations to Help Scale (MtHS) which was designed to fit to the population of medical students.Results: Among the 731 completers, 52% were working as volunteers during the pandemic in different medical areas, most in hospitals and only a few in other areas (9% in public health departments, 6% in outpatient services), 37% would have liked to work but did not get an appropriate employment, and 21% did not intend to voluntarily support the hospital staff. Their mental burden during work was rather low, while they were somewhat affected by the personal fate of the patients. With respect to their motivations to volunteer as measured with the MtHS, Altruistic Intentions/Helping (Cronbach's alpha = 0.898) scored highest, followed by Practical Application/Learning (Cronbach's alpha = 0.808), while Role Testing/Recognition (Cronbach's alpha = 0.702) scored lowest. Those who volunteered had significantly higher scores for Altruistic Intentions/Helping and Practical Application/Learning, while the different phases of medical study (preclinical phase, clinical phase, and higher semester) had no influence on the extent of the students' motivation. The motivations to help were not at all or only marginally (inversely) related to indicators of stress and burden, while Altruistic Intentions/Helping was weakly related to affections by patients' fate.Conclusions: Medical students' intention to support healthcare professionals as supplementary assistants were both prosocial and proself motivated. With this opportunity to practically apply their current knowledge and to improve their skills and competences, volunteering students might be more motivated for their further studies and their future career as compassionate medical doctors.

The classical nova CP Puppis has been observed to have particularly puzzling and peculiar properties. In particular, this classical nova displays occasional bursts in its long-term ASAS-SN light curve. Here, we report on five sectors of TESS data displaying two of these rapid bursts, lasting ∼1 d. Based on the estimated lower energy limits of the bursts, we discuss whether the bursts may be examples of micronovae resulting from localized thermonuclear explosion. Furthermore, its orbital period remains uncertain, with several inconsistent periodic signals appearing in spectroscopic and photometric observations at various wavelengths. Although we cannot unambiguously unravel the physical origin of the signals, the previously suggested nature of CP Puppis as a long orbital period system may be a viable explanation. The recurrence time of the bursts in CP Puppis, together with the unexplained variable modulations make it a prime candidate for intense monitoring. [ABSTRACT FROM AUTHOR]

Abstract Background High-risk neuroblastoma with N-Myc amplification remains a therapeutic challenge in paediatric oncology. Antagonism of pro-death Bcl-2 homology (BH) proteins to pro-survival BH members such as Mcl-1 and Bcl-2 has become a treatment approach, but previous studies suggest that a combined inhibition of Bcl-2 and Mcl-1 is necessary. TW-37 inhibits Mcl-1 and Bcl-2 with almost the same affinity. However, single-agent cytotoxicity of TW-37 in neuroblastoma cell lines has not been investigated. Methods Cell viability, apoptosis, proliferation and changes in growth properties were determined in SKNAS, IMR-5, SY5Y and Kelly cells after treatment with TW-37. After transfection with Mcl-1 or Bcl-2 siRNA, apoptosis and proliferation were investigated in Kelly cells. Mice with Kelly cell line xenografts were treated with TW-37 and tumor growth, survival and apoptosis were determined. Results Cell lines with N-Myc amplification were more sensitive to TW-37 treatment, IC50 values for IMR-5 and Kelly cells being 0.28 μM and 0.22 μM, compared to SY5Y cells and SKNAS cells (IC50 0.96 μM and 0.83 μM). Treatment with TW-37 resulted in increased apoptosis and reduced proliferation rates, especially in IMR5 and Kelly cells. Bcl-2 as well as Mcl-1 knockdown induced apoptosis in Kelly cells. TW-37 led to a decrease in tumor growth and a favorable survival (p = 0.0379) in a Kelly neuroblastoma xenografts mouse model. Conclusion TW-37 has strong single-agent cytotoxicity in vitro and in vivo. Therefore, combined inhibition of Bcl-2/Mcl-1 by TW-37 in N-Myc amplified neuroblastoma may represent an interesting therapeutic strategy.

BACKGROUND:Atherosclerosis is the primary cause of coronary artery disease (CAD). Several observational studies have examined the association of traditional CAD risk factors with the progression of coronary artery calcification (CAC). In our study we investigated the effect of 11 different genetic risk scores associated with CAD and CAD risk factors on the progression of CAC. METHODS AND RESULTS:We included 3097 participants from the Heinz Nixdorf Recall study who had available CAC measurements at baseline (CACb) and at the 5-year follow-up (CAC5y). A weighted genetic risk score for CAD and each of the CAD-associated risk factors was constructed. Multiple regression analyses were applied to i) the difference between the observed log(CAC5y+1) (log(obs)) and expected log(CAC5y+1) (log(exp)) at the 5-year follow-up following the individual's log(CACb+1) percentile for the time between scans (log(obs)-log(exp)) and ii) the 5-year CAC progression, defined as 5*(log(CAC5y+1)-log(CACb+1))/time between the scans, adjusted for age, sex, and log(CACb+1) as well as for risk factors. The median percent deviation from the expected (CAC5y+1) and the 5-year progression of (CAC+1) in our study were 0 (first quartile: Q1; third quartile: Q3: -0.32; 0.48) and 45.4% (0%; 171.0%) respectively. In the age-, sex- and log(CACb+1)-adjusted model, the per-standard deviation (SD) increase in CAD genetic risk score was associated with the percent deviation from the expected (CAC5y+1) (9.7% (95% confidence interval: 5.2%; 14.5%), p = 1.6x10-5) and the 5-year progression of CAC (7.1% (3.0%; 11.4%), p = 0.0005). The CAD genetic risk score explains an additional 0.6% of the observed phenotypic variance for "log(obs)-log(exp)" and 0.4% for 5-year progression of CAC. Additionally, the per-SD increase in the CAC genetic risk score was associated with the percent deviation from the expected (CAC5y+1) (6.2% (1.9%; 10.8%, p = 0.005)) explaining an additional 0.2% of the observed phenotypic variance. However, the per-SD increase in the CAC genetic risk score was not associated with the 5-year progression of CAC (4.4% (0.4%; 8.5%), p = 0.03) after multiple testing. Adjusting for risk factors did not change the results. None of the other genetic risk scores showed an association with the percent deviation from the expected (CAC5y+1) or with the 5-year progression of CAC. CONCLUSIONS:The association of the CAC genetic risk score and the CAD genetic risk score provides evidence that genetic determinants for CAC and CAD influence the progression of CAC.

Previous studies reported on the broad-spectrum antiviral function of heparin. Here we investigated the antiviral function of magnesium-modified heparin and found that modified heparin displayed a significantly enhanced antiviral function against human adenovirus (HAdV) in immortalized and primary cells. Nuclear magnetic resonance analyses revealed a conformational change of heparin when complexed with magnesium. To broadly explore this discovery, we tested the antiviral function of modified heparin against herpes simplex virus type 1 (HSV-1) and found that the replication of HSV-1 was even further decreased compared to aciclovir. Moreover, we investigated the antiviral effect against the new severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and measured a 55-fold decreased viral load in the supernatant of infected cells associated with a 38-fold decrease in virus growth. The advantage of our modified heparin is an increased antiviral effect compared to regular heparin.

Background: Prenyltrasferases (PTases) are a class of enzymes known to be responsible for promoting posttranslational modification at the carboxyl terminus of proteins containing a so‐called CaaX‐motif. The process is responsible for proper membrane localization and the appropriate function of several intracellular signaling proteins. Current research demonstrating the pathomechanistic importance of prenylation in inflammatory illnesses emphasizes the requirement to ascertain the differential expression of PT genes under inflammatory settings, particularly in periodontal disease. Methods: Telomerase‐immortalized human gingival fibroblasts (HGF‐hTert) were cultured and treated with either inhibitors of prenylation (PTI) lonafarnib, tipifarnib, zoledronic acid, or atorvastatin at concentrations of 10 μM in combination with or without 10 μg Porphyromonas gingivalis lipopolysaccharide (LPS) for 24 h. Prenyltransferase genes FNTB, FNTA, PGGT1B, RABGGTA, RABGGTB, and PTAR1 as well as inflammatory marker genes MMP1 and IL1B were detected using quantitative real‐time polymerase chain reaction (RT‐qPCR). Immunoblot and protein immunoassay were used to confirm the results on the protein level. Results: RT‐qPCR experiments revealed significant upregulation of IL1B, MMP1, FNTA, and PGGT1B upon LPS treatment. PTase inhibitors caused significant downregulation of the inflammatory cytokine expression. Interestingly, FNTB expression was significantly upregulated in response to any PTase inhibitor in combination with LPS, but not upon LPS treatment only, indicating a vital role of protein farnesyltransferase in the proinflammatory signaling cascade. Conclusions: In this study, distinct PTase gene expression patterns in pro‐inflammatory signaling were discovered. Moreover, PTase inhibiting drugs ameliorated inflammatory mediator expression by a significant margin, indicating that prenylation is a major pre‐requisite for innate immunity in periodontal cells. [ABSTRACT FROM AUTHOR]

Geranylgeranyltransferase type-I (GGTase-I) represents an important drug target since it contributes to the function of many proteins that are involved in tumor development and metastasis. This led to the development of GGTase-I inhibitors as anti-cancer drugs blocking the protein function and membrane association of e.g., Rap subfamilies that are involved in cell differentiation and cell growth. In the present study, we developed a new NanoBiT assay to monitor the interaction of human GGTase-I and its substrate Rap1B. Different Rap1B prenylation-deficient mutants (C181G, C181S, and ΔCQLL) were designed and investigated for their interaction with GGTase-I. While the Rap1B mutants C181G and C181S still exhibited interaction with human GGTase-I, mutant ΔCQLL, lacking the entire CAAX motif (defined by a cysteine residue, two aliphatic residues, and the C-terminal residue), showed reduced interaction. Moreover, a specific, peptidomimetic and competitive CAAX inhibitor was able to block the interaction of Rap1B with GGTase-I. Furthermore, activation of both Gαs-coupled human adenosine receptors, A2A (A2AAR) and A2B (A2BAR), increased the interaction between GGTase-I and Rap1B, probably representing a way to modulate prenylation and function of Rap1B. Thus, A2AAR and A2BAR antagonists might be promising candidates for therapeutic intervention for different types of cancer that overexpress Rap1B. Finally, the NanoBiT assay provides a tool to investigate the pharmacology of GGTase-I inhibitors.