CME Dermatology 23Answers Hidradenitis suppurativa

The B7-H6-NKp30 complex on the tumor membrane activates the NK cells and releases both tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). B7-H6 is highly expressed in a wide range of tumor cells, including glioma, hematologic malignant tumors, and breast cancer cells. Clinical examination of cancer patients indicated that the expression of B7-H6 is related to distant metastasis status and permits postoperative prognosis. Because of its unique properties, B7-H6 has a high potential be utilized as a biological marker for cancer diagnosis and prognosis, as well as a target for novel treatment options.Disordered scaffold proteins provide multivalent landing pads that, via a series of embedded Short Linear Motifs (SLiMs), bring together the components of a complex to orchestrate precise spatial and temporal regulation of cellular processes. One such protein is AKAP5 (previously AKAP79), which contains SLiMs that anchor PKA and Calcineurin, and recruit substrate (the TRPV1 receptor). Calcineurin is anchored to AKAP5 by a well-characterised PxIxIT SLiM. Here we show, using a combination of biochemical and biophysical approaches, that the Calcineurin PxIxIT-binding groove also recognises several hitherto unknown lower-affinity SLiMs in addition to the PxIxIT motif. We demonstrate that the assembly is in reality a complex system with conserved SLiMs spanning a wide affinity range. The capture is analogous to that seen for many DNA-binding proteins that have a weak non-specific affinity for DNA outside the canonical binding site, but different in that it involves (i) two proteins, and (ii) hydrophobic rather than electrostatic interactions. It is also compatible with the requirement for both stable anchoring of the enzyme and responsive downstream signalling. We conclude that the AKAP5 C-terminus is enriched in lower-affinity/mini-SLiMs that, together with the canonical SLiM, maintain a structurally disordered but tightly regulated signalosome.The FimH protein of Escherichia coli is a model two-domain adhesin that is able to mediate an allosteric catch bond mechanism of bacterial cell attachment, where the mannose-binding lectin domain switches from an 'inactive' conformation with fast binding to mannose to an 'active' conformation with slow detachment from mannose. Because mechanical tensile force favors separation of the domains and, thus, FimH activation, it has been thought that the catch bonds can only be manifested in a fluidic shear-dependent mode of adhesion. Here, we used recombinant FimH variants with a weakened inter-domain interaction and show that a fast and sustained allosteric activation of FimH can also occur under static, non-shear conditions. Moreover, it appears that lectin domain conformational activation happens intrinsically at a constant rate, independently from its ability to interact with the pilin domain or mannose. However, the latter two factors control the rate of FimH deactivation. Thus, the allosteric catch bond mechanism can be a much broader phenomenon involved in both fast and strong cell-pathogen attachments under a broad range of hydrodynamic conditions. This concept that allostery can enable more effective receptor-ligand interactions is fundamentally different from the conventional wisdom that allostery provides a mechanism to turn binding off under specific conditions.Flavonoids are widely distributed in plants as secondary metabolites and have various biological benefits such as anti-tumor, anti-oxidant, anti-inflammatory and anti-aging. We previously reported that 4,4'-dimethoxychalcone (DMC) suppressed cancer cell proliferation by aggravating oxidative stress and inducing G2/M cell cycle arrest. In the present study, we explored the underlying mechanisms by which DMC inhibited cancer cell growth. Given that ferrochelatase (FECH) is a potential target of DMC identified by thermal proteome profiling (TPP) method, herein, we confirmed that DMC inhibited the enzymatic activity of FECH. Furthermore, we proved that DMC induced Keap1 degradation via ubiquitin-proteasome system, which led to the nuclear translocation of Nrf2 and upregulated Nrf2 targeted gene HMOX1. FECH inhibition and HMOX1 upregulation resulted in iron overload and triggered ferroptosis in cancer cells. Collectively, we revealed that DMC induced ferroptosis by synergistically activating Keap1/Nrf2/HMOX1 pathway and inhibiting FECH. Our findings indicate that FECH contributes to the non-canonical ferroptosis induction, shed light on the mechanisms of DMC inhibiting cancer cell growth, and set an example for studying biological functions of flavonoids.Triptolide (TPL) is a bioactive component extracted from the traditional Chinese herb Tripterygium wilfordii Hook F., and has multiple pharmacological activities, such as anti-tumor activity. However, severe adverse effects and toxicity, especially nephrotoxicity, limit its clinical application. It has been demonstrated that mitochondrial defect is a major toxic effects of TPL. In this study, we show that triptolide activated the cGAS-STING signaling pathway in kidney tubular cells in vivo and in vitro. Renal injury models were established in BALB/c mice and human tubular epithelial cells using TPL. We found that TPL enhanced the phosphorylation levels of STING, TBK1 and IRF3, and upregulated the expression of IFNβ, which is the production of cGAS-STING signaling pathway. STING inhibitor C176 had protective effects in TPL-induced nephrocyte damage. STING siRNA down regulated the expression level of IFNβ. Bcl-2 inhibitor In addition, triptolide induced an increase in protein levels of the transcription factor BACH1, while transcriptional expression of the antioxidant enzyme HMOX1 was reduced due to the increased expression of BACH1. Furthermore, oxidative stress-induced mtDNA damage and DNA leakage caused activation of the cGAS-STING signaling pathway. Altogether, cGAS-STING signaling pathway involved in TPL induced nephrotoxicity. Inhibiting cGAS-STING over-activation may be a new strategy for alleviating renal injury of triptolide.
We evaluated whether Angiotensin receptor/Neprilysin inhibitors (ARNI) reduce heart failure (HF) hospitalizations and deaths in cardiac resynchronization therapy with defibrillator (CRTd) non-responders patients at 12 months of follow-up, modulating microRNAs (miRs) implied in adverse cardiac remodeling.
adverse cardiac remodeling characterized by left ventricle ejection fraction (LVEF) reduction, left ventricular end-systolic volume (LVESv) increase, and the 6-minute walking test (6MWT) reduction are relevant pathological mechanisms in CRTd non-responders and could be linked to changes in miRNAs (miRs), regulating cardiac fibrosis, apoptosis, and hypertrophy.
miRs levels and clinical outcomes (LVEF, cardiac deaths, and 6MWT) were evaluated at baseline and one year of follow-up in CRTd non-responders divided into ARNI-users and Non-ARNI users.
At baseline, there were no differences in levels of inflammatory markers, miR-18, miR-145, and miR-181 (p>0.05) between Non-ARNI users (n 106) and ARNI-users (n 312). At one year of follow-up, ARNI-users vs. Non-ARNI users showed lowest inflammatory markers (p<0.01) and miR-181 levels (p<0.01) and higher values of miR-18 (p<0.01)and miR-145 (p<0.01). At one year of follow-up, ARNI-users had a higher increase of LVEF (p<0.01) and 6MWT (p<0.01) along with a more significant reduction of LVESv (p<0.01) compared to Non-ARNI users. Cox regression analysis evidenced that ARNI-based therapies increase the probability of anti-remodeling effects of CRTd. Based on symptomatic improvements, echocardiographic and functional classification improvements, 37 (34.9%) patients among ARNI-users became responders, while only twenty (6.4%) patients became responders among Non-ARNi-users.
ARNI might influence epigenetic mechanisms modulating miRs implicated in the adverse cardiac remodeling responses to CRTd.
ARNI might influence epigenetic mechanisms modulating miRs implicated in the adverse cardiac remodeling responses to CRTd.Negatively charged microspheres (NCMs) are postulated as a new form of treatment for chronic wounds. Despite the efficacy shown at clinical level, more studies are required to demonstrate their safety and local effect. The objective of the work was to confirm the lack of NCM systemic absorption performing a biodistribution study of the NCMs in an open wound rat animal model. To this end, radiolabeling of NCMs with technetium-99 m was optimized and biodistribution studies were performed by in vivo SPEC/CT imaging and ex vivo counting during 24 h after topical administration. The studies were performed on animals treated with a single or repeated dose to study the effect of macrophages during a prolonged treatment. NCM radiolabeling was achieved in a simple, efficient and stable manner with high yield. SPECT/CT images showed that almost all NCMs (about 85 %) remained on the wound for 24 h either after single or multiple administrations. Ex vivo biodistribution studies confirmed that there was no accumulation of NCMs in any organ or tissue except in the wound area, suggesting a lack of absorption. In conclusion, NCMs can be considered safe as local wound treatment since they remain at the administration area.Olsalazine is a typical 5-aminosalicylic acid (5-ASA) drug that depends on gut microbiota to liberate its anti-inflammatory moiety 5-ASA in the treatment of ulcerative colitis (UC). In recent decades, 5-ASA drugs combined with probiotics have achieved a better effective treatment for UC. Mechanisms of combination therapy have been widely discussed from a pharmacodynamic perspective. However, it is still unclear whether the better therapeutic efficacy of combination therapy was made by changing the metabolism of 5-ASA drugs in the colon under the regulation of probiotics. In the present study, combined with pharmacokinetic and gut microbiota analyses, we systematically evaluated the potential effect of Lactobacillus acidophilus (L. acidophilus) on the metabolism of Olsalazine at three levels (pharmacokinetic characteristics, metabolic microbiota, and metabolic enzymes) to offer some insights into this issue. As pharmacokinetic results showed, L. acidophilus barely had an influence on the pharmacokinetic parameiota perspectives.
To show a new mini-invasive surgical technique of ovarian drilling and fertility workup using transvaginal natural orifice transluminal endoscopic surgery (vNOTES).
Stepwise demonstration of the technique with narrated video footage.
Ovarian drilling is a surgical technique for patients with dysovulatory polycystic ovary syndrome. The aim of this technique is to destroy 5% to 10% of the ovarian cortex to restore spontaneous ovulation. Drilling is proposed as a second-line treatment in case of failure of treatments with clomid, metformin, or letrozole. The Cochrane 2020 review shows that drilling has the same pregnancy rate as the other second-line treatment stimulation with gonadotropins [1]. After ovarian drilling, the results show 80% of spontaneous ovulation within 3 months and 50% of spontaneous pregnancy within a year; these results are effective in the long term [2]. The techniques used until now were either classic laparoscopy or transvaginal hydrolaparoscopy, which is currently not feasible owing to the cessation of the kit [3,4].