Carbon powder-filled microelectrode: An easy-to-fabricate probe for cellular electrochemistry.

Carbon fiber and carbon fiber disc microelectrodes are widely used for electrochemical detection of biochemicals released from cells. However, fabricating these types of microelectrodes is difficult and time-consuming. Here, we report an easy-to-fabricate, carbon powder-filled microelectrode consisting of a pulled glass capillary backfilled with carbon powder. Carbon tip size and responsiveness can be controlled by adjusting the settings of the puller. Carbon powder-filled microelectrodes with tip opening diameters of 7-24 µm detected sub-micromolar to sub-millimolar levels of dopamine and catecholamines released from PC-12 cells. This simple microelectrode should promote further work on cellular and tissue electrochemistry.

A test potential booster for fast-scan cyclic voltammetry with an electrophysiological amplifier.

Fast-scan cyclic voltammetry (FSCV) is a powerful technique for studying the local dynamics of neurotransmitters and neuromodulators. FSCV is attractive to researchers employing electrophysiological techniques because it can be performed using an electrophysiological voltage-clamp amplifier. However, the narrow test potential range of electrophysiological amplifiers (typically, ±1 V) limits testable species of analytes. Here we devised a booster that extends the test potential range. Using the booster, we could detect the oxidation current of adenosine peaking near a test potential of +1.5 V. The booster should promote combined electrophysiological and electrochemical studies of synaptic release and neural secretion.

Automated classification of hip fractures using deep convolutional neural networks with orthopedic surgeon-level accuracy: ensemble decision-making with antero-posterior and lateral radiographs.

Background and purpose - Deep-learning approaches based on convolutional neural networks (CNNs) are gaining interest in the medical imaging field. We evaluated the diagnostic performance of a CNN to discriminate femoral neck fractures, trochanteric fractures, and non-fracture using antero-posterior (AP) and lateral hip radiographs. Patients and methods - 1,703 plain hip AP radiographs and 1,220 plain hip lateral radiographs were included in the total dataset. 150 images each of the AP and lateral views were separated out and the remainder of the dataset was used for training. The CNN made the diagnosis based on: (1) AP radiographs alone, (2) lateral radiographs alone, or (3) both AP and lateral radiographs combined. The diagnostic performance of the CNN was measured by the accuracy, recall, precision, and F1 score. We further compared the CNN's performance with that of orthopedic surgeons. Results - The average accuracy, recall, precision, and F1 score of the CNN based on both anteroposterior and lateral radiographs were 0.98, 0.98, 0.98, and 0.98, respectively. The accuracy of the CNN was comparable to, or statistically significantly better than, that of the orthopedic surgeons regardless of radiographic view used. In the CNN model, the accuracy of the diagnosis based on both views was significantly better than the lateral view alone and tended to be better than the AP view alone. Interpretation - The CNN exhibited comparable or superior performance to that of orthopedic surgeons to discriminate femoral neck fractures, trochanteric fractures, and non-fracture using both AP and lateral hip radiographs.

[Risk factors for cardiotoxicity during fluorouracil and cisplatin combination chemotherapy].

We investigated the incidence of cardiovascular symptoms in patients treated with fluorouracil and cisplatin (FP) combination chemotherapy. Between April 2010 and March 2011, 61 patients were treated with FP therapy at the Department of Gastroenterology, Niigata Prefectural Cancer Center Hospital. Within 1 week of treatment and within the first or second course of therapy, six patients developed chest pain. To investigate the risk factors for cardiotoxicity following FP therapy, patients were divided into cardiotoxicity incidence and non-incidence groups. The prevalence of diabetes, hypertension, and heart disease was not significantly different between the two groups. Furthermore, serum sodium and potassium levels were not altered following FP therapy. Therefore, no definitive risk factors for cardiotoxicity were identified. These results suggest that while FP chemotherapy-induced nausea, vomiting, and renal damage are serious adverse effects, further attention should also be paid to the potential cardiotoxic effects of FP therapy.

[Prophylaxis with acyclovir for herpes zoster infection during bortezomib-dexamethasone combination therapy].

A novel molecular targeting drug, a proteasome inhibitor, bortezomib (Bor), has been reported to be highly effective for relapsed/refractory, as well as for newly diagnosed multiple myeloma, but is also associated with a high frequency of herpes zoster (HZ) infection (13%). We conducted a retrospective survey on HZ infection (profile) after Bor therapy in our hospital. Six of 30 patients developed HZ infection during bortezomib-dexamethasone treatment (BD therapy). Age, performance status, and stem cell transplantation were not related risk factors for HZ infection. HZ developed when acyclovir (ACV) was not administrated to all six cases. Continuous administration of ACV decreased the incidence of HZ infection. Based on these results, we started an anti- HZ prophylaxis program using ACV for all patients receiving BD therapy. Further study is warranted to establish the optimal dose and duration of ACV for appropriate prophylaxis of HZ infection.