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By phasing out production and consumption of most ozone-depleting substances (ODSs), the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) has avoided consequences of increased ultraviolet (UV) radiation and will restore stratospheric ozone to pre-1980 conditions by mid-century, assuming compliance with the phaseout. However, several studies have documented an unexpected increase in emissions and suggested unreported production of trichlorofluoromethane (CFC-11) and potentially other ODSs after 2012 despite production phaseouts under the Montreal Protocol. Furthermore, because most ODSs are powerful greenhouse gases (GHGs), there are significant climate protection benefits in collecting and destroying the substantial quantities of historically allowed production of chemicals under the Montreal Protocol that are contained in existing equipment and products and referred to as ODS “banks”. This technical note presents a framework for considering offsets to ozone depletion, climate forcing, and other environmental impacts arising from occurrences of unexpected emissions and unreported production of Montreal Protocol controlled substances, as recently experienced and likely to be experienced again. We also show how this methodology could be applied to the destruction of banks of controlled ODSs and GHGs or to halon or other production allowed under a Montreal Protocol Essential Use Exemption or Critical Use Exemption. Further, we roughly estimate the magnitude of offset each type of action could provide for ozone depletion, climate, and other environmental impacts that Montreal Protocol Parties agree warrant remedial action.

Lymphoid restricted membrane protein (LRMP) is a specific regulator of the hyperpolarization-activated cyclic nucleotide-sensitive isoform 4 (HCN4) channel. LRMP prevents cAMP-dependent potentiation of HCN4, but the interaction domains, mechanisms of action, and basis for isoform-specificity remain unknown. Here, we identify the domains of LRMP essential for this regulation, show that LRMP acts by disrupting the intramolecular signal transduction between cyclic nucleotide binding and gating, and demonstrate that multiple unique regions in HCN4 are required for LRMP isoform-specificity. Using patch clamp electrophysiology and Förster resonance energy transfer (FRET), we identified the initial 227 residues of LRMP and the N-terminus of HCN4 as necessary for LRMP to associate with HCN4. We found that the HCN4 N-terminus and HCN4-specific residues in the C-linker are necessary for regulation of HCN4 by LRMP. Finally, we demonstrated that LRMP-regulation can be conferred to HCN2 by addition of the HCN4 N-terminus along with mutation of five residues in the S5 region and C-linker to the cognate HCN4 residues. Taken together, these results suggest that LRMP inhibits HCN4 through an isoform-specific interaction involving the N-terminals of both proteins that prevents the transduction of cAMP binding into a change in channel gating, most likely via an HCN4-specific orientation of the N-terminus, C-linker, and S4-S5 linker.

Subarachnoid hemorrhage (SAH) is a common form of hemorrhagic stroke associated with high rates of mortality and severe disability. SAH patients often develop severe neurological deficits days after ictus, events attributed to a phenomenon referred to as delayed cerebral ischemia (DCI). Recent studies indicate that SAH-induced DCI results from a multitude of cerebral circulatory disturbances including cerebral autoregulation malfunction. Cerebral autoregulation incorporates the influence of blood pressure (BP) on arterial diameter in the homeostatic regulation of cerebral blood flow (CBF), which is necessary for maintaining constant brain perfusion during physiological swings in systemic BP. In this study, we quantitatively examined the impact of SAH on cerebral autoregulation using a mouse endovascular perforation model and a newly developed approach combining absolute and relative CBF measurements. This method enables a direct quantitative comparison of cerebral autoregulation between individual animals (e.g., SAH vs. control or sham-operated mice), which cannot be done solely using relative CBF changes by laser Doppler flowmetry. Here, absolute CBF was measured via injection of fluorescent microspheres at a baseline BP. In separate groups of animals, in vivo laser Doppler flowmetry was used to measure relative CBF changes over a range of BP using phlebotomy and the pressor phenylephrine to lower and raise BP, respectively. Absolute CBF measurements from microspheres were then used to calibrate laser Doppler measurements to calculate the relationship between CBF and BP, i.e., “cerebral autoregulation curves.” Un-operated and sham-operated groups exhibited similar cerebral autoregulatory curves, showing comparable levels of relatively constant CBF over a range of BP from ~80 mmHg to ~130 mmHg. In contrast, SAH animals exhibited a narrower autoregulatory range of BP, which was primarily due to a decrease in the upper limit of BP whereby cerebral autoregulation was maintained. Importantly, SAH animals also exhibited a marked decrease in CBF throughout the entire range of BP. In sum, this study provides evidence of the dramatic reduction in cortical CBF and the diminished range of autoregulation after SAH. Furthermore, this novel methodology should pave the way for future studies examining pathological mechanisms and/or therapeutic strategies targeting impaired cerebral autoregulation, a pathology common to many cardiovascular and cerebrovascular disorders.

Abstract Background Foot and ankle pain is common in the Australian adult population. People with musculoskeletal foot and ankle conditions are often referred for surgical opinion, yet how patients are managed prior to referral is largely unknown. The aim of this study was to determine the characteristics and management of patients with musculoskeletal foot and ankle complaints prior to public-sector orthopaedic referral in South Australia. Methods People with non-urgent foot or ankle complaints were recruited over a 12-month period from the waiting-lists of three tertiary hospitals in Adelaide, Australia. Participants completed a questionnaire on their medical history, duration and location of their foot or ankle complaint, diagnosis of their condition, previous treatment and medical imaging. The Manchester-Oxford Foot and Ankle Questionnaire, and the EuroQol-5D-5 L measured foot/ankle pain severity and health-related-quality-of-life (HRQoL). Descriptive statistics were generated for sample demographics, medical history and foot/ankle symptoms. Multivariable regressions were used to explore factors associated with foot/ankle pain severity and whether participants considered an operation necessary. Results Two hundred and thirty-three adults returned questionnaires, with a survey response rate of 38.4% (66.1% female, median age 57.7 years IQR 18.5, BMI 29.3 kg/m2 IQR 8.7). Half of the participants had seen a podiatrist (52.8%), and 36.5% did not see any other health professional prior to orthopaedic referral. Sixty-five (27.9%) had not yet been given a diagnosis. BMI was positively associated with foot/ankle pain severity (β 0.48, 95% CI 0.05, 0.92), while HRQoL had a negative association (β − 0.31, 95% CI -0.45, − 0.18). Participants told by their GP that they may need an operation were significantly more likely to consider surgery necessary (OR 31.41, 95% CI 11.30, 87.35), while older people were less likely (OR 0.94, 95% CI 0.90, 0.98). Conclusions More than one-third of the participants had not accessed allied-health care prior to specialist orthopaedic referral. Participants may consider their GPs opinion on the necessity of surgery compelling, and most expected to undergo surgery, but many couldn’t report their diagnosis. The discordance between the expectation of surgery and historically low surgical conversion rates suggests more work is necessary to improve the management of this group.

Abstract Background The aim of this study was to evaluate the cost-consequences of a podiatry-led triage clinic provided in an orthopaedic department relative to usual care for non-urgent foot and ankle complaints in an Australian tertiary care hospital. Methods All new, non-urgent foot and ankle patients seen in an outpatient orthopaedic department were included in this study. The patients seen between 2014 and 2015 by Orthopaedic Surgeons were considered ‘usual care’, the patients seen between 2015 and 2016 by a Podiatrist were considered the ‘Podiatry Triage Clinic’. Data on new and review patient appointments; the number of new patients / session; the number of appointments / patient; the number of patients discharged; the surgical conversion rate; staff time; and imaging use were collected. A cost-consequences analysis, undertaken from a healthcare provider perspective (hospital) estimated the incremental resource use, costs and effects of the Podiatry Triage Clinic relative to usual care over a 12-month period. Results The Orthopaedic Surgeons and Podiatrist consulted with 72 and 212 new patients during the usual care and triage periods, respectively. The Podiatrist consulted with more new patients / session, mean (SD) of 3.6 (1.0) versus 0.7 (0.8), p

Objectives: In this study, we examined the possibility of using targeted antibodies and the potential of small molecular therapeutics (acetylcholine, nicotine and tacrine) to block the pro-inflammatory and adhesion-related properties of monomeric C-reactive protein (mCRP).Methods: We used three established models (platelet aggregation assay, endothelial leucocyte binding assay and monocyte inflammation via ELISA and Western blotting) to assess the potential of these therapeutics.Results: The results of this study showed that monocyte induced inflammation (raised tumor necrosis factor-alpha-TNF-α) induced by mCRP was significantly blocked in the presence of acetylcholine and nicotine, whilst tacrine and targeted antibodies (clones 8C10 and 3H12) had less of or no significant effects. Western blotting confirmed the ability of acetylcholine to inhibit mCRP-induced cell signaling phosphorylation of extracellular signal regulated kinase 1/2 (ERK1/2), p38 and nuclear factor-kappa B (NF-κB). There was no evidence of direct binding between small molecules and mCRP. mCRP also induced endothelial cell-monocyte adhesion in a dose dependent fashion, however, both acetylcholine and nicotine as well as targeting antibodies notably inhibited adhesion. Finally, we investigated their effects on mCRP-induced platelet aggregation. All three small molecules significantly attenuated platelet aggregation as did the antibody 8C10, although 3H12 had a weaker effect.Discussion: Acetylcholine and to a lesser extent nicotine show potential for therapeutic inhibition of mCRP-induced inflammation and cell and platelet adhesion. These results highlight the potential of targeted antibodies and small molecule therapeutics to inhibit the binding of mCRP by prevention of membrane interaction and subsequent activation of cellular cascade systems, which produce the pro-inflammatory effects associated with mCRP.

Circulating C-reactive protein (CRP) is a key acute-phase protein and one of the main clinical biomarkers for inflammation and infection. CRP is an important upstream mediator of inflammation and is associated with the onset of a number of important disease states including cardiovascular disease and neurodegenerative disorders such as Alzheimer’s disease. This pentraxin exerts pro-inflammatory properties via dissociation of the pentamer (pCRP) to a monomeric form (mCRP). This dissociation is induced by binding of pCRP to cell surface phosphocholine residues exposed by the action of phospholipase A2 (PLA2). Given the association of CRP with the onset of a range of serious disease states this CRP dissociation process is a tempting drug target for the development of novel small-molecule therapeutics. This review will discuss potential targets for chemotherapeutic intervention elucidated during studies of CRP-mediated inflammation and provide an up-to-date summary of the development of small molecules, not only targeted directly at inhibiting conversion of pCRP to mCRP, but also those developed for activity against PLA2, given the key role of this enzyme in the activation of CRP.