A B S T R A C T Cardiovascular actions of insulin were studied by intravenous infusions of insulin (4 and 8 mU/kg per min) in normal conscious dogs. This resulted in increases in cardiac output, heart rate, and left ventricular derivative of pressure with respect to time (dP/dt) and dP/dt/P, as blood glucose was reduced. The inotropic and chronotropic effects of insulin were not related to hypoglycemia, as they persisted even when blood glucose was restored to control values or when it was prevented from falling by a simultaneous infusion of glucose. These cardiac effects were accompanied by increases in plasma catecholamines, and were abolished by propranolol pretreatment. Both plasma epinephrine and norepinephrine increased during insulin hypoglycemia, but only norepinephrine increased during insulin infusion when euglycemia was maintained.Mean arterial blood pressure did not change significantly during insulin hypoglycemia, but rose if euglycemia was maintained, probably due to the selective increase in norepinephrine in the latter condition. A pressor response also occurred in propranolol-pretreated dogs during insulin hypoglycemia, but was abolished when the animals also had been pretreated Insulin infusion increased left ventricular work and myocardial blood flow in dogs with and without hypoglycemia. Myocardial blood flow, however, did not change significantly during insulin infusion in dogs pretreated with propranolol. As propranolol also diminished the inotropic response, it appears that the increase in myocardial blood flow caused by insulin in the normal dog is causally related to the increased myocardial metabolic demand.Insulin also produced vasomotor effects on other vascular beds. In skeletal muscle, blood flow was increased under all study conditions, except during insulin hypoglycemia after propranolol-pretreatment when unopposed alpha-mediated vasoconstriction was present. The persistent increase in flow during both alpha and beta adrenergic blockade suggests that insulin has a direct dilator effect on skeletal muscle vasculature. In the adrenal gland, flow was increased except during euglycemia, when no rise in plasma epinephrine was observed, suggesting coupling between adrenal flow and catecholamine release. In the splanchnic bed, flow was decreased during euglycemia, when plasma norepinephrine rose, and during beta adrenergic blockade with propranolol, when unopposed alpha-mediated vasoconstriction also predominated. A similar pattern was found in the kidney, except that renal blood flow also fell after combined alpha and beta adrenergic blockade. The results show that the vasomotor effects on regional flows are mediated both via adrenergic mechanisms, and in the case of skeletal muscle and kidney, via mechanisms unrelated to sympathetic stimulation.
Platelets have been implicated in pulmonary inflammatory cell recruitment after exposure to allergic and nonallergic stimuli, but little is known about the role of platelets in response to pulmonary infection with Pseudomonas aeruginosa. In this study, we have investigated the impact of the experimental depletion of circulating platelets on a range of inflammatory and bacterial parameters, and their subsequent impact on mortality in a murine model of pulmonary infection with P. aeruginosa. P. aeruginosa infection in mice induced a mild, but significant, state of peripheral thrombocytopenia in addition to pulmonary platelet accumulation. Increased platelet activation was detected in infected mice through increased levels of the platelet-derived mediators, platelet factor-4 and β-thromboglobulin, in BAL fluid and blood plasma. In mice depleted of circulating platelets, pulmonary neutrophil recruitment was significantly reduced 24 hours after infection, whereas the incidence of systemic dissemination of bacteria was significantly increased compared with non-platelet-depleted control mice. Furthermore, mortality rates were increased in bacterial-infected mice depleted of circulating platelets. This work demonstrates a role for platelets in the host response toward a gram-negative bacterial respiratory infection.
Platelets are recruited to inflammatory foci and contribute to host defence and inflammatory responses. Compared to platelet recruitment in haemostasis and thrombosis, the mechanisms of platelet recruitment in inflammation and host defence are poorly understood. Neutrophil recruitment to lung airspaces following inhalation of bacterial LPS requires platelets and PSGL-1 in mice. Given this association between platelets and neutrophils, we investigated whether recruitment of platelets to lungs of mice following LPS inhalation was dependent on PSGL-1, P-selectin, or interaction with neutrophils.BALB/c mice were administered intranasal LPS (O55:B5, 5 mg/kg) and 48 hours later lungs were collected, and platelets and neutrophils were quantified in tissue sections by immunohistochemistry.The effects of functional blocking antibody treatments targeting the platelet-neutrophil adhesion molecules P-selectin, or PSGL-1, or treatment with a neutrophil depleting antibody targeting Ly6G, were tested on the extent of LPS-induced lung platelet recruitment. Separately in Pf4-Cre×mTmG mice, two-photon intravital microscopy was used to image platelet adhesion in live lungs.Inhalation of LPS caused both platelet and neutrophil recruitment to the lung vasculature. However, decreasing lung neutrophil recruitment by blocking PSGL-1, P-selectin, or depleting blood neutrophils had no effect on lung platelet recruitment. Lung intravital imaging revealed increased adhesion of platelets in the lung microvasculature which was not associated with thrombus formation.In conclusion, platelet recruitment to lungs in response to LPS occurs through mechanisms distinct from those mediating neutrophil recruitment, or the occurrence of pulmonary emboli.
, we found six more relevant studies. In total, we included 23 studies with 2648 participants. These studies compared the painkilling ability (benefit) and side effects (harms) of different types of oxycodone to each other or to other strong painkillers. Key results Generally, the studies showed that oxycodone is an equally effective strong painkiller whether taken every six or every hours, and equally effective as other strong pain killers, such as morphine. All the strong painkillers examined in the studies were also associated with a number of unwanted effects, such as vomiting, constipation, and drowsiness. Overall, these do not differ between oxycodone and the other strong painkillers. Hallucinations (where people experience imaginary things, e.g. hearing voices) are much less common as a side effect but we found that they were less likely with oxycodone than within morphine. Overall, we found that the current evidence is comprised of studies that contained small numbers of participants of which many (19%) did not complete the studies. However, since there was very little difference between oxycodone and morphine, more research in this area is unlikely. Studies looking at oxycodone compared to other strong pain killers may be useful. Quality of the evidence We rated the quality of the evidence from studies using four levels: very low, low, moderate, or high. Very low quality evidence means that we are very uncertain about the results. High quality evidence means that we are very confident in the results. Overall the quality of the evidence was low or very low, downgraded because of issues with study quality and size.
BackgroundMany patients with cancer experience moderate to severe pain that requires treatment with strong analgesics. Buprenorphine, fentanyl and morphine are examples of strong opioids used for the relief of cancer pain. Strong opioids are, however, not e ective for pain in all patients nor are they well-tolerated by all patients. The aim of this Cochrane review is to assess whether buprenorphine is associated with superior, inferior or equal pain relief and tolerability compared to other analgesic options for patients with cancer pain. ObjectivesTo assess the e ectiveness and tolerability of buprenorphine for pain in adults and children with cancer.
Summary Background Various treatments for acne vulgaris exist, but little is known about their comparative effectiveness in relation to acne severity. Objectives To identify best treatments for mild‐to‐moderate and moderate‐to‐severe acne, as determined by clinician‐assessed morphological features. Methods We undertook a systematic review and network meta‐analysis of randomized controlled trials (RCTs) assessing topical pharmacological, oral pharmacological, physical and combined treatments for mild‐to‐moderate and moderate‐to‐severe acne, published up to May 2020. Outcomes included percentage change in total lesion count from baseline, treatment discontinuation for any reason, and discontinuation owing to side‐effects. Risk of bias was assessed using the Cochrane risk‐of‐bias tool and bias adjustment models. Effects for treatments with ≥ 50 observations each compared with placebo are reported below. Results We included 179 RCTs with approximately 35 000 observations across 49 treatment classes. For mild‐to‐moderate acne, the most effective options for each treatment type were as follows: topical pharmacological – combined retinoid with benzoyl peroxide (BPO) [mean difference 26·16%, 95% credible interval (CrI) 16·75–35·36%]; physical – chemical peels, e.g. salicylic or mandelic acid (39·70%, 95% CrI 12·54–66·78%) and photochemical therapy (combined blue/red light) (35·36%, 95% CrI 17·75–53·08%). Oral pharmacological treatments (e.g. antibiotics, hormonal contraceptives) did not appear to be effective after bias adjustment. BPO and topical retinoids were less well tolerated than placebo. For moderate‐to‐severe acne, the most effective options for each treatment type were as follows: topical pharmacological – combined retinoid with lincosamide (clindamycin) (44·43%, 95% CrI 29·20–60·02%); oral pharmacological – isotretinoin of total cumulative dose ≥ 120 mg kg−1 per single course (58·09%, 95% CrI 36·99–79·29%); physical – photodynamic therapy (light therapy enhanced by a photosensitizing chemical) (40·45%, 95% CrI 26·17–54·11%); combined – BPO with topical retinoid and oral tetracycline (43·53%, 95% CrI 29·49–57·70%). Topical retinoids and oral tetracyclines were less well tolerated than placebo. The quality of included RCTs was moderate to very low, with evidence of inconsistency between direct and indirect evidence. Uncertainty in findings was high, in particular for chemical peels, photochemical therapy and photodynamic therapy. However, conclusions were robust to potential bias in the evidence. Conclusions Topical pharmacological treatment combinations, chemical peels and photochemical therapy were most effective for mild‐to‐moderate acne. Topical pharmacological treatment combinations, oral antibiotics combined with topical pharmacological treatments, oral isotretinoin and photodynamic therapy were most effective for moderate‐to‐severe acne. Further research is warranted for chemical peels, photochemical therapy and photodynamic therapy for which evidence was more limited. What is already known about this top...
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