Project description:A 17-year-old girl was admitted with acute abdominal pain, vomiting and a leucocytosis, and was initially thought to have appendicitis. She underwent laparoscopic appendicectomy, where the tip of the appendix was noted to be mildly inflamed and she was discharged home the day after surgery. Two days later, she re-presented with small bowel obstruction which was subsequently demonstrated to be due to ingestion of five magnetic beads. She required a laparotomy and small bowel resection to resolve the obstruction, but has since fully recovered. This case highlights the potential intestinal complications caused by the intake of magnetic objects, and based on a literature review a number of recommendations are made to guide clinicians when managing similar cases.
Project description:The RAS-regulated RAF-MEK1/2-ERK1/2 pathway promotes cell proliferation and survival and RAS and BRAF proteins are commonly mutated in cancer. This has fuelled the development of small molecule kinase inhibitors including ATP-competitive RAF inhibitors. Type I and type I½ ATP-competitive RAF inhibitors are effective in BRAFV600E/K-mutant cancer cells. However, in RAS-mutant cells these compounds instead promote RAS-dependent dimerisation and paradoxical activation of wild-type RAF proteins. RAF dimerisation is mediated by two key regions within each RAF protein; the RKTR motif of the αC-helix and the NtA-region of the dimer partner. Dimer formation requires the adoption of a closed, active kinase conformation which can be induced by RAS-dependent activation of RAF or by the binding of type I and I½ RAF inhibitors. Binding of type I or I½ RAF inhibitors to one dimer partner reduces the binding affinity of the other, thereby leaving a single dimer partner uninhibited and able to activate MEK. To overcome this paradox two classes of drug are currently under development; type II pan-RAF inhibitors that induce RAF dimer formation but bind both dimer partners thus allowing effective inhibition of both wild-type RAF dimer partners and monomeric active class I mutant RAF, and the recently developed "paradox breakers" which interrupt BRAF dimerisation through disruption of the αC-helix. Here we review the regulation of RAF proteins, including RAF dimers, and the progress towards effective targeting of the wild-type RAF proteins.
Project description:The lactose permease (LacY) of Escherichia coli is the prototype of the major facilitator superfamily, one of the largest families of membrane transport proteins. Structurally, two pseudo-symmetrical six-helix bundles surround a large internal aqueous cavity. Single binding sites for galactoside and H+ are positioned at the approximate center of LacY halfway through the membrane at the apex of the internal cavity. These features enable LacY to function by an alternating-access mechanism that can catalyze galactoside/H+ symport in either direction across the cytoplasmic membrane. The H+-binding site is fully protonated under physiological conditions, and subsequent sugar binding causes transition of the ternary complex to an occluded intermediate that can open to either side of the membrane. We review the structural and functional evidence that has provided new insight into the mechanism by which LacY achieves active transport against a concentration gradient.
Project description:Hippo pathway with its main molecule YAP is a crucial pathway for development, tissue homeostasis, wound healing, tissue regeneration, and cancer. In this review, we discuss the multiple effects of the YAP/Hippo pathway in the immune system and cancer. We analyzed a series of effects: extracellular vesicles enhanced immunity through inhibition of LATS1/2, ways of modulation of the tumor microenvironment, YAP- and TAZ-mediated upregulation of PDL1, high expression of YAP and PDL1 in EGFR-TKI-resistant cells, enhanced YAP activity in inflammation, and the effect of the Hippo pathway on T cells, B cells, Tregs, macrophages, and myeloid-derived suppressor cells (MDSCs). These pleiotropic effects render the YAP and Hippo pathway a key pathway for exploitation in the future, in order to enhance our immunotherapy treatment strategies in oncology.
Project description:Endobronchial ultrasound (EBUS) is indispensable when it comes to evaluation of mediastinal lesion and staging of lung cancer. The incorporation of endoscopic ultrasound using an echobronchoscope (EUS-B) further extends this capability to the paraoesophageal and subdiaphragmatic structures. When combined, EBUS with EUS-B increases the diagnostic yield. Both procedures can be done in a single session and by a single operator; this translates into an overall reduction in the healthcare cost.
Project description:Tumor-infiltrating lymphocytes (TILs), frontline soldiers of the adaptive immune system, are recruited into the tumor site to fight against tumors. However, their small number and reduced activity limit their ability to overcome the tumor. Enhancement of TILs number and activity against tumors has been of interest for a long time. A lack of knowledge about the tumor microenvironment (TME) has limited success in primary TIL therapies. Although the advent of engineered T cells has revolutionized the immunotherapy methods of hematologic cancers, the heterogeneity of solid tumors warrants the application of TILs with a wide range of specificity. Recent advances in understanding TME, immune exhaustion, and immune checkpoints have paved the way for TIL therapy regimens. Nowadays, TIL therapy has regained attention as a safe personalized immunotherapy, and currently, several clinical trials are evaluating the efficacy of TIL therapy in patients who have failed conventional immunotherapies. Gaining favorable outcomes following TIL therapy of patients with metastatic melanoma, cervical cancer, ovarian cancer, and breast cancer has raised hope in patients with refractory solid tumors, too. Nevertheless, TIL therapy procedures face several challenges, such as high cost, timely expansion, and technical challenges in selecting and activating the cells. Herein, we reviewed the recent advances in the TIL therapy of solid tumors and discussed the challenges and perspectives.
Project description:ObjectivesThis article examines the association between cognitive impairment, including mild cognitive impairment (MCI) and early dementia (ED), and sexual activity in a large, longitudinal sample of community-dwelling older adults. We focus here on sexual activity, which includes both sexual activity with a partner and masturbation.MethodsWe analyzed 3,777 older individuals and members of 955 intimate dyads using the National Social Life, Health, and Aging Project (2010 and 2015). We used ordered probit regression, cross-lagged panels models, and probit regression.ResultsWe find that older adults with cognitive limitations, either MCI or ED, are about as likely to be sexually active with a partner as those with normal cognitive function. This is the case both in the cross-section and longitudinally. Both men and women with ED are less likely to have masturbated, however. Among married and cohabiting couples, we find no association between cognitive impairment in either the husband, the wife, or in both partners and their joint sexual activity. Women whose measured cognitive function is lower than their husbands are less likely to report any masturbation.DiscussionSex with a partner, a fundamentally social activity, seems to be conserved in the face of cognitive limitation but masturbation, a solitary activity, does not. We argue that the intimate dyad plays an important role in conserving partnered sexual activity. Results can inform strategies to maintain the sexual well-being of older adults with cognitive impairment and their partners as part of overall strategies to improve quality of life.
Project description:Acute-on-chronic liver failure (ACLF) is characterized by the acute decompensation of cirrhosis associated with organ failure and high short-term mortality. The key event in the pathogenesis is a dysfunctional immune response arising from exacerbation of the two main immunological alterations already present in cirrhosis: systemic inflammation and immune cell paralysis. High-grade systemic inflammation due to predominant activation and dysregulation of the innate immune response leads to the massive release of cytokines. Recognition of acutely increased pathogen and damage-associated molecular patterns by specific receptors underlies its pathogenesis and contributes to tissue damage and organ failure. In addition, an inappropriate compensatory anti-inflammatory response over the course of ACLF, along with the exhaustion and dysfunction of both the innate and adaptive immune systems, leads to functional immune cell paralysis. This entails a high risk of infection and contributes to a poor prognosis. Therapeutic approaches seeking to counteract the immune alterations present in ACLF are currently under investigation.
Project description:Small heat-shock proteins (sHsps) are ubiquitous molecular chaperones, and sHsp mutations or altered expression are linked to multiple human disease states. sHsp monomers assemble into large oligomers with dimeric substructure, and the dynamics of sHsp oligomers has led to major questions about the form that captures substrate, a critical aspect of their mechanism of action. We show here that substructural dimers of two plant dodecameric sHsps, Ta16.9 and homologous Ps18.1, are functional units in the initial encounter with unfolding substrate. We introduced inter-polypeptide disulfide bonds at the two dodecameric interfaces, dimeric and nondimeric, to restrict how their assemblies can dissociate. When disulfide-bonded at the nondimeric interface, mutants of Ta16.9 and Ps18.1 (TaCT-ACD and PsCT-ACD) were inactive but, when reduced, had WT-like chaperone activity, demonstrating that dissociation at nondimeric interfaces is essential for sHsp activity. Moreover, the size of the TaCT-ACD and PsCT-ACD covalent unit defined a new tetrahedral geometry for these sHsps, different from that observed in the Ta16.9 X-ray structure. Importantly, oxidized Tadimer (disulfide bonded at the dimeric interface) exhibited greatly enhanced ability to protect substrate, indicating that strengthening the dimeric interface increases chaperone efficiency. Temperature-induced size and secondary structure changes revealed that folded sHsp dimers interact with substrate and that dimer stability affects chaperone efficiency. These results yield a model in which sHsp dimers capture substrate before assembly into larger, heterogeneous sHsp-substrate complexes for substrate refolding or degradation, and suggest that tuning the strength of the dimer interface can be used to engineer sHsp chaperone efficiency.
Project description:BackgroundDespite a growing global commitment to universal health coverage, considerable vaccine coverage and uptake gaps persist in resource-constrained settings. One way of addressing the gaps is by ensuring product innovation is relevant and responsive to the needs of these contexts. Total Systems Effectiveness (TSE) framework has been developed to characterize preferred vaccine attributes from the perspective of country decision-makers to inform research and development (R&D) of products. A proof of concept pilot study took place in Thailand in 2018 to examine the feasibility and usefulness of the TSE approach using a rotavirus hypothetical test-case.MethodsThe excel-based model used multiple-criteria decision analysis (MCDA) to compare and evaluate five hypothetical rotavirus vaccine products. The model was populated with local data and products were ranked against decision criteria identified by Thai stakeholders. A one-way sensitivity analysis was performed to identify criteria that influenced vaccine ranking. Self-assessment forms were distributed to R&D stakeholders on the usability of the approach and were subsequently analysed.ResultsThe model identified significant parameters that impacted on MCDA rankings. Self-assessment forms revealed that TSE was perceived as being able to encourage closer collaboration between country decision makers and vaccine developers.ConclusionsThe pilot study demonstrates that it is feasible to use an MCDA approach to elicit stakeholder preferences and determine influential parameters to help identify the preferred product characteristics for R&D from the perspective of country decision-makers. It found that TSE can help steer manufacturers to develop products that are better aligned with country need. Findings will guide further development of the TSE concept.