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Primary afferent sensory neurons are incredibly long cells, often traversing distances of over 1 m in humans. Cutaneous sensory stimuli are transduced in the periphery by specialised end organs or free nerve endings, which code the stimulus into electrical action potentials that propagate towards the central nervous system. Despite significant advances in our knowledge of sensory neuron physiology and ion channel expression, many commonly used techniques fail to accurately model the primary afferent neuron in its entirety. In vitro experiments often focus on the cell somata and neglect the fundamental processes of peripheral stimulus transduction and action potential propagation. Despite this, these experiments are commonly used as a model for cellular investigations of the receptive terminals. We demonstrate that ratiometric calcium imaging performed in compartmentalised sensory neuron cultures can be used to directly and accurately compare the sensitivity and functional protein expression of isolated neuronal regions in vitro. Using microfluidic chambers, we demonstrate that the nerve terminals of cultured dorsal root ganglion neurons can be depolarised to induce action potential propagation, which has both tetrodotoxin-resistant and tetrodotoxin-sensitive components. Furthermore, we show that there is a differential regulation of proton sensitivity between the sensory terminals and somata in cultured sensory neurons. We also demonstrate that capsaicin sensitivity is highly dependent on embryonic dissection age. This approach enables a comprehensive method to study the excitability and regional sensitivity of cultured sensory neurons on a single-cell level. Examination of the sensory terminals is crucial to further understand the properties and diversity of dorsal root ganglion sensory neurons.

p16 INK4a immunohistochemistry (IHC) is widely used to facilitate the diagnosis of human papillomavirus (HPV)-associated cervical precancerous lesions. Although most p16 results are distinctly positive or negative, certain ones are ambiguous: they meet some but not all requirements for the "block-positive" pattern. It is unclear whether ambiguous p16 immunoreactivity indicates oncogenic HPV infection or risk of progression. Herein, we compared HPV genotypes and subsequent high-grade squamous intraepithelial lesion (HSIL) outcomes among 220 cervical biopsies with a differential diagnosis of cervical intraepithelial neoplasia 2 based on hematoxylin and eosin morphology and varying degrees of p16 immunoreactivity. p16 results were classified as block positive (n=40, 18%), negative (n=130, 59%), or ambiguous (n=50, 23%), a category we further grouped into 3 patterns: strong/basal (n=18), strong/focal (n=15), and weak/diffuse (n=17). Seventy percent of ambiguous p16 lesions were negative for the most common low- and high-risk HPV types; the remaining 30% were positive for HPV 16, 18, 45, 58, 59, or 66. Three patterns revealed comparably low HPV detection rates (28%, 27%, and 35%). During 12-month surveillance, HSILs were detected in 35% of the p16 block-positive group, 1.5% of negative group, and 16% of the ambiguous group. The accuracy of ambiguous p16 immunoreactivity in predicting oncogenic HPV and HSIL outcome is significantly lower than that of the block-positive pattern but greater than negative staining. Specific guidelines for this intermediate category should prevent diagnostic errors and help implement p16 IHC in general practice., (Copyright © 2017 Elsevier Inc. All rights reserved.)

We are reporting a case of a 59-year-old woman, with a family history of breast cancer, who presented with extranodal marginal zone lymphoma (MALT) of the left breast. She received definitive radiation therapy and remains without evidence of disease. Here, we present a case and review the current literature to determine the optimal treatment of this rare presentation of MALT.

The presentation of a MALT lymphoma in the bladder is exceedingly rare. Furthermore, the optimal treatment of primary MALT confined to the bladder remains to be defined. Here, we report a case of a 65-year-old female with primary MALT lymphoma treated with definitive radiation therapy. The patient received a total dose of 30 Gy in 20 equal daily fractions to the bladder and tolerated the treatment well. In addition, we have extensively reviewed the relevant literature to better define the optimal management of this rare disease. In conclusion, primary MALT lymphoma of the bladder represents a rare malignancy with excellent prognosis if detected at an early stage. For early stage disease, definitive radiation represents an excellent treatment modality with a minimal side-effect profile.

Objectives: Recent health policy changes have focused efforts on reducing emergency department (ED) visits as a way to reduce costs and improve quality of care. This was a systematic review of interventions based outside the ED aimed at reducing ED use., Methods: This study was designed as a systematic review. We reviewed the literature on interventions in five categories: patient education, creation of additional non-ED capacity, managed care, prehospital diversion, and patient financial incentives. Studies written in English, with interventions administered outside of the ED, and a comparison group where ED use was an outcome, were included. Two independent reviewers screened search results using MEDLINE, Cochrane, OAIster, or Scopus. The following data were abstracted from included studies: type of intervention, study design, population, details of intervention, effect on ED use, effect on non-ED health care use, and other health and financial outcomes. Quality of individual articles was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE) guidelines., Results: Of 39 included studies, 34 were observational and five were randomized controlled trials. Two of five studies on patient education found reductions in ED use ranging from 21% to 80%. Out of 10 studies of additional non-ED capacity, four showed decreases of 9% to 54%, and one a 21% increase. Both studies on prehospital diversion found reductions of 3% to 7%. Of 12 studies on managed care, 10 had decreases ranging from 1% to 46%. Nine out of 10 studies on patient financial incentives found decreases of 3% to 50%, and one a 34% increase. Nineteen studies reported effect on non-ED use with mixed results. Seventeen studies included data on health outcomes, but 13 of these only included data on hospitalizations rather than morbidity and mortality. Seven studies included data on cost outcomes. According to the GRADE guidelines, all studies had at least some risk of bias, with four moderate quality, one low quality, and 34 very low quality studies., Conclusions: Many studies have explored interventions based outside the ED to reduce ED use in various populations, with mixed evidence. Approximately two-thirds identified here showed reductions in ED use. The interventions with the greatest number of studies showing reductions in ED use include patient financial incentives and managed care, while the greatest magnitude of reductions were found in patient education. These findings have implications for insurers and policymakers seeking to reduce ED use., (© 2013 by the Society for Academic Emergency Medicine.)

Mutations in the enzyme glycyl-tRNA synthetase (GARS) cause motor and sensory axon loss in the peripheral nervous system in humans, described clinically as Charcot-Marie-Tooth type 2D or distal spinal muscular atrophy type V. Here, we characterise a new mouse mutant, Gars(C201R), with a point mutation that leads to a non-conservative substitution within GARS. Heterozygous mice with a C3H genetic background have loss of grip strength, decreased motor flexibility and disruption of fine motor control; this relatively mild phenotype is more severe on a C57BL/6 background. Homozygous mutants have a highly deleterious set of features, including movement difficulties and death before weaning. Heterozygous animals have a reduction in axon diameter in peripheral nerves, slowing of nerve conduction and an alteration in the recovery cycle of myelinated axons, as well as innervation defects. An assessment of GARS levels showed increased protein in 15-day-old mice compared with controls; however, this increase was not observed in 3-month-old animals, indicating that GARS function may be more crucial in younger animals. We found that enzyme activity was not reduced detectably in heterozygotes at any age, but was diminished greatly in homozygous mice compared with controls; thus, homozygous animals may suffer from a partial loss of function. The Gars(C201R) mutation described here is a contribution to our understanding of the mechanism by which mutations in tRNA synthetases, which are fundamentally important, ubiquitously expressed enzymes, cause axonopathy in specific sets of neurons.

Neurons of the peripheral nervous system detect changes in temperature through activation of specialised ion channels. Members of the transient receptor potential family TRPM8 and TRPA1 are candidates for the principal transducers of cold stimuli. Using ratiometric calcium imaging we now show that 19% of acutely dissociated mouse dorsal root (DRG) and 45% of superior cervical ganglia (SCG) neurons responded to a brief cold stimulus. Amongst cold-responsive DRG neurons 34+/-2% responded to the TRPM8 agonist menthol, 18+/-3% to the TRPA1 agonist mustard oil and 5% to both stimuli. A third of the cold-sensitive neurons did not respond to any TRP channel agonist. Cold-sensitive neurons of the SCG did not respond to menthol and only 3% responded to mustard oil. The threshold of SCG neurons was at significantly cooler temperatures than that of DRG neurons. Using real-time PCR, TRPA1 was expressed over 100-fold more in DRG than SCG, while TRPM8 was present in DRG only. The relatively small amount of TRPA1 transcript present in SCG did not correlate with the high level of cold sensitivity. We conclude that cold sensitivity in sympathetic neurons and in a significant proportion of sensory neurons is generated in the absence of TRPM8 and TRPA1.