Rejected

Mice and rats are valuable and commonly used as models for the study of cancer. The models and methods of experimentation have the potential to cause pain to some degree, and all charged with ensuring animal welfare must determine how to manage it. A commonly posed question, especially from investigators and IACUC, is whether the provision of analgesic agents will render the model invalid. Left untreated, pain is a stressor and has negative consequences, most notably immune system perturbations. In addition, analgesic agents in the opioid and NSAID drug classes exhibit immunomodulatory activity and influence processes such as cell proliferation, apoptosis, and angiogenesis that are important in cancer formation. Therefore,both pain and the agents used to alleviate it have the potential to act as confounding factors in a study. This review article presents data from both human medicine and work with animal models in an attempt to help inform discussions about the withholding of analgesic agents from animals used in cancer studies.

There are several treatment options for patients suffering from lumbar spinal stenosis, including surgical and conservative care. Interspinous spacer decompression using the Superion device offers a less invasive procedure for patients who fail conservative treatment before traditional decompression surgery. This review assesses the current cost-effectiveness, safety, and performance of lumbar spinal stenosis treatment modalities compared with the Superion interspinous spacer procedure.

An association of anxiety with surgical outcomes has been suggested, including with open ventral hernia repair (OVHR). This study examines the interaction of multiple comorbidities, including anxiety, depression, chronic pain, and hernia characteristics with outcomes after OVHR.

Inappropriate diagnostic imaging is a burgeoning problem within the Canadian healthcare system and imposes considerable burdens to efficiency and timeliness of care. Low back pain and headaches affect an immense portion of the general population and have become exceedingly common complaints from patients seeking diagnostic imaging from primary care physicians.

Distal anterior cerebral artery aneurysms are rare, comprising approximately 6% of all intracranial aneurysms. These aneurysms tend to be smaller in size, broad-based, associated with additional aneurysms and at arterial branching sites, which can make both diagnosis and treatment difficult. Here we report a case of a 63-year-old female who presented with headache and perioral paresthesia determined to be Hunt & Hess scale grade 1. Computed tomography angiography discovered a medium-sized left A2 trunk saccular aneurysm. Intraoperatively 2 additional small blister type aneurysms not noted on initial computed tomography were discovered and treated via clipping and wrapping, respectively. Postoperatively a cerebral angiogram revealed an additional small right A2 trunk broad-based aneurysm. Preoperative evaluation of cerebral vasculature with a cerebral angiogram or high-resolution digital subtraction angiography is essential as multiple aneurysms are commonly associated with anterior cerebral artery aneurysms. The patient was successfully treated without any operative or postoperative complications and has remained symptom-free at 1 year follow up.

Epilepsy is a chronic disorder that causes unprovoked, recurrent seizures. Status epilepticus (SE) is a medical emergency associated with significant morbidity and mortality. Morphine has been the cornerstone of pain controlling medicines for a long time. In addition to the analgesic and opioid responses, morphine has also revealed anticonvulsant effects in different epilepsy models including pentylenetetrazole (PTZ)-induced seizures threshold. Some authors suggest that nitric oxide (NO) pathway interactions of morphine explain the reason for its pro or anticonvulsant activities. To induce SE, injection of a single dose of lithium chloride (127 mg/kg, intraperitoneal (i.p.)) 20 h before pilocarpine (60 mg/kg, i.p.) was used. Administration of morphine (15 mg/kg, i.p.) inhibited the SE and decreased the mortality in rats when injected 30 min before pilocarpine. On the other hand, injection of L-N-nitro arginine methyl ester (L-NAME, a nonselective NO synthase (NOS) blocker; 10 mg/kg, i.p.), 7-nitroindazole (7-NI, a neuronal NOS (nNOS) blocker; 30 mg/kg, i.p.), and aminoguanidine (AG, an inducible NOS (iNOS) blocker; 50 mg/kg, i.p.) 15 min before morphine, significantly reversed inhibitory effect of morphine on SE. Subsequently, measurement of nitrite metabolite levels in the hippocampus of SE-induced rats displayed high levels of nitrite metabolite for the control group. However, after injection of morphine in SE-induced rats, nitrite metabolite levels reduced. In conclusion, these findings demonstrated that NO pathway (both nNOS and iNOS) interactions are involved in the anticonvulsant effects of morphine on the SE signs and mortality rate induced by lithium-pilocarpine in rats.

Cortical spreading depression (CSD) is a wave of transient intense neuronal firing leading to a long lasting depolarizing block of neuronal activity. It is a proposed pathological mechanism of migraine with aura. Some forms of migraine are associated with a genetic mutation of the Na channel, resulting in its gain of function and implying hyperexcitability of interneurons. This leads to the counterintuitive hypothesis that intense firing of interneurons can cause CSD ignition. To test this hypothesis in silico, we developed a computational model of an E-I pair (a pyramidal cell and an interneuron), in which the coupling between the cells in not just synaptic, but takes into account also the effects of the accumulation of extracellular potassium caused by the activity of the neurons and of the synapses. In the context of this model, we show that the intense firing of the interneuron can lead to CSD. We have investigated the effect of various biophysical parameters on the transition to CSD, including the levels of glutamate or GABA, frequency of the interneuron firing and the efficacy of the KCC2 co-transporter. The key element for CSD ignition in our model was the frequency of interneuron firing and the related accumulation of extracellular potassium, which induced a depolarizing block of the pyramidal cell. This constitutes a new mechanism of CSD ignition.

Spontaneous breathing anesthesia (SBA) may have advantages over general anesthesia for cervical tracheal resection and reconstruction (TRR), avoiding the difficulties and complication caused by endotracheal intubation and surgical cross-field intubation. This prospective study evaluates SBA for cervical TRR.

BACKGROUND: While it is generally considered to be a disease of adolescence, acne affects an increasing number of adults, especially women. Although data exist on the use of retinoids in adult females, there is no universal agreement as to the age of onset of adult female acne, or data on the efficacy and tolerability dependent on age. A novel tretinoin 0.05% lotion formulation has been shown to be effective and well-tolerated in acne patients with moderate or severe disease.

OBJECTIVE: To evaluate the safety and efficacy of once-daily tretinoin 0.05% lotion in women with moderate or severe acne categorized into different age groups (13-19, 20-29, and 30+ years).

METHODS: Post hoc analysis of two multicenter, randomized, double-blind, vehicle-controlled phase 3 studies. Women (aged 13-19 years, N=357; 20-29 years, N=352; 30+ years, N=156) with moderate or severe acne were randomized (1:1) to receive tretinoin 0.05% lotion or vehicle, once-daily for 12 weeks. Efficacy assessments included changes in baseline inflammatory/noninflammatory lesions and treatment success (at least 2-grade reduction in Evaluator’s Global Severity Score [EGSS] and ‘clear’/’almost clear’) and Quality of Life (QoL) using the validated Acne-QoL questionnaire. Safety and adverse events (AEs) where evaluated throughout; cutaneous tolerability assessed at each study visit using a 4-point scale (where 0=none and 3=severe).

RESULTS: At baseline, 91.9% (N=794) of women in the post hoc analysis had moderate (EGSS=3) and 8.1% (N=70) severe (EGSS=4) acne, with the highest proportion of women (11.1%, N=39) having severe acne being aged 20-29 years. Baseline inflammatory lesion counts were similar across the three age ranges, with more comedonal lesions (44.5) in adolescent females (aged 13-19 years). Quality of life at baseline was much better in adolescent females and may be age-related for some domains (self-perception and role-social). At week 12, there appeared to be an age-related improvement in both inflammatory and noninflammatory lesion counts, and treatment success although the differences between groups were not significant. Mean percent reduction in inflammatory and noninflammatory lesion counts for each age group (13-19, 20-29, and 30+ years old respectively) were 55.3% (P=0.019 versus vehicle), 55.8% (P=0.080) and 63.5%; and 47.1% (P<0.001), 55.2% (P=0.002) and 59.0% (P=0.030). Treatment success for the 3 groups was achieved by 23.2% (P=0.023), 21.3%, and 30.7% of patients, respectively, at week 12; differences between age groups were not significant. Quality of Life improved in all age groups, although changes with tretinoin 0.05% lotion were only significant compared with vehicle in adult females aged 20-29 years (self-perception, role-emotional and acne symptoms); improvements in each domain score by week 12 were also greatest in this age group. The majority of AEs were mild and transient; the most common treatment emergent AEs were application site pain and dryness especially in the older adult females (aged 30+ years). Local cutaneous safety and tolerability assessments were generally mild and improved by week 12. There were transient increases in scaling, burning and stinging in the adolescent females, peaking at week 4; all mean scores were ≤0.6 where 1=mild.

CONCLUSIONS: Tretinoin 0.05% lotion was significantly more effective than vehicle in achieving treatment success and reducing inflammatory and comedonal lesions in adult and adolescent females with moderate or severe acne. There appear to be age-related efficacy and tolerability benefits favoring adult females.

J Drugs Dermatol. 2019;18(12):1218-1225.