Long-Term Potentiation of Excitatory Synaptic Strength in Spinothalamic Tract Neurons of the Rat Spinal Cord

Spinal dorsal horn nociceptive neurons have been shown to undergo long-term synaptic plasticity, including long-term potentiation (LTP) and long-term depression (LTD). Here, we focused on the spinothalamic tract (STT) neurons that are the main nociceptive neurons projecting from the spinal cord to the thalamus. Optical technique using fluorescent dye has made it possible to identify the STT neurons in the spinal cord. Evoked fast mono-synaptic, excitatory postsynaptic currents (eEPSCs) were measured in the STT neurons. Time-based tetanic stimulation (TBS) was employed to induce long-term potentiation (LTP) in the STT neurons. Coincident stimulation of both pre- and postsynaptic neurons using TBS showed immediate and persistent increase in AMPA receptor-mediated EPSCs. LTP can also be induced by postsynaptic spiking together with pharmacological stimulation using chemical NMDA. TBS-induced LTP observed in STT neurons was blocked by internal BAPTA, or Ni²⁺, a T-type VOCC blocker. However, LTP was intact in the presence of L-type VOCC blocker. These results suggest that long-term plastic change of STT neurons requires NMDA receptor activation and postsynaptic calcium but is differentially sensitive to T-type VOCCs.     

A prospective,multicenter phase II study of continuous infusion of FLAG for patients older than 60 yr with resistant acute myeloid leukemia: a comparison with intensive younger patients’ trial

Relapsed or refractory acute myeloid leukemia (R/R AML) in elderly (≥60 yr old) patients were eligible. Induction chemotherapy consisted fludarabine and cytarabine (ARAC) as a 24‐hr CI without idarubicin (C‐FLAG), which was compared with the results of C‐FLAG with idarubicin (CI‐FLAG2) in younger patients’ trial. A total of 33 and 68 patients were enrolled in C‐FLAG and CI‐FLAG2, respectively. CR, CRp, and CRi were achieved in 10 (30.3%), 3 (9.1%), and 2 (6.1%), respectively. When comparing outcomes between C‐FLAG and CI‐FLAG2, there were no difference in terms of CR rate (P = 0.572) and objective response rate (ORR; P = 0.899). Favorable predictors on ORR in C‐FLAG were PB WBC ≤ 20K/uL at salvage (P = 0.024) and early evaluation peripheral BLAST = 0% (P = 0.013) on multivariate analysis. The overall survival of patients who achieve CR/CRp/CRi showed significantly prolonged survival compared with patients who did not in C‐FLAG (P < 0.001) and was a favorable predictor of longer survival by multivariate analysis (P = 0.009). Median overall survival was 3.19 (95% CI, 2.05–4.33) months and similar with that of CI‐FLAG2 (P = 0.841). Attenuated salvage regimen C‐FLGA in elderly patients was as effective as more intensive younger patients’ regimen CI‐FLAG2 in terms of response and survival although elderly patients had more unfavorable clinical characteristics.     

Yoga Training Improves Metabolic Parameters in Obese Boys

Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p<0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p<0.01). HDL-cholesterol was decreased in both groups (p<0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys.     

Microsurgical anatomy of the abducens nerve

The aim of this study is to demonstrate and review the detailed microsurgical anatomy of the abducens nerve and surrounding structures along its entire course and to provide its topographic measurements. Ten cadaveric heads were examined using ×3 to ×40 magnification after the arteries and veins were injected with colored silicone. Both sides of each cadaveric head were dissected using different skull base approaches to demonstrate the entire course of the abducens nerve from the pontomedullary sulcus to the lateral rectus muscle. The anatomy of the petroclival area and the cavernous sinus through which the abducens nerve passes are complex due to the high density of critically important neural and vascular structures. The abducens nerve has angulations and fixation points along its course that put the nerve at risk in many clinical situations. From a surgical viewpoint, the petrous tubercle of the petrous apex is an intraoperative landmark to avoid damage to the abducens nerve. The abducens nerve is quite different from the other nerves. No other cranial nerve has a long intradural path with angulations and fixations such as the abducens nerve in petroclival venous confluence. A precise knowledge of the relationship between the abducens nerve and surrounding structures has allowed neurosurgeon to approach the clivus, petroclival area, cavernous sinus, and superior orbital fissure without surgical complications. Clin. Anat. 25:1030–1042, 2012. © 2012 Wiley Periodicals, Inc.     

Bubble dynamics in boiling histotripsy

Boiling histotripsy is a non-invasive, cavitation-based ultrasonic technique which uses a number of millisecond pulses to mechanically fractionate tissue. Though a number of studies have demonstrated the efficacy of boiling histotripsy for fractionation of solid tumours, treatment monitoring by cavitation measurement is not well studied because of the limited understanding of the dynamics of bubbles induced by boiling histotripsy. The main objectives of this work are to (a) extract qualitative and quantitative features of bubbles excited by shockwaves and (b) distinguish between the different types of cavitation activity for either a thermally or a mechanically induced lesion in the liver. A numerical bubble model based on the Gilmore equation accounting for heat and mass transfer (gas and water vapour) was developed to investigate the dynamics of a single bubble in tissue exposed to different High Intensity Focused Ultrasound fields as a function of temperature variation in the fluid. Furthermore, ex vivo liver experiments were performed with a passive cavitation detection system to obtain acoustic emissions. The numerical simulations showed that the asymmetry in a shockwave and water vapour transport are the key parameters which lead the bubble to undergo rectified growth at a boiling temperature of 100°C. The onset of rectified radial bubble motion manifested itself as (a) an increase in the radiated pressure and (b) the sudden appearance of higher order multiple harmonics in the corresponding spectrogram. Examining the frequency spectra produced by the thermal ablation and the boiling histotripsy exposures, it was observed that higher order multiple harmonics as well as higher levels of broadband emissions occurred during the boiling histotripsy insonation. These unique features in the emitted acoustic signals were consistent with the experimental measurements. These features can, therefore, be used to monitor (a) the different types of acoustic cavitation activity for either a thermal ablation or a mechanical fractionation process and (b) the onset of the formation of a boiling bubble at the focus in the course of HIFU exposure.     

Surgical Outcomes of Canalicular Trephination Combined with Endoscopic Dacryocystorhinostomy in Patients with Distal or Common Canalicular Obstruction

PurposeThis study investigated the surgical outcomes of canalicular trephination combined with endoscopic dacryocystorhinostomy (DCR) in patients with a distal or common canalicular obstruction. It also identified the factors affecting surgical success rates associated with this technique.MethodsWe retrospectively reviewed the medical records of 57 patients (59 eyes) in whom a canalicular obstruction was encountered during endoscopic DCR. All patients were treated with endoscopic DCR, followed by canalicular trephination and silicone tube placement. The surgical outcome was categorized as a functional success according to the patient''s subjective assessment of symptoms, including epiphora, and as an anatomical success according to a postoperative nasolacrimal duct irrigation test. Surgical success rates were compared based on age, sex, location of the obstruction, number of silicone tubes, and experience of the surgeon.ResultsFunctional success was achieved in 55 of 59 eyes (93%) at one month, 50 eyes (84%) at three months, and 46 eyes (78%) at six months. Anatomical success was achieved in 58 of 59 eyes (98%) at one month, 52 eyes (88%) at three months, and 50 eyes (84%) at six months. There was a statistically significant difference in surgical outcome according to the experience of the surgeon. The anatomical success rate at the six-month follow-up exam was 95.4% in the >5 years of experience group, and 53.3% in the <5 years of experience group (p = 0.008, Pearson chi-square test).ConclusionsThe success rate of canalicular trephination combined with endoscopic DCR in patients with a distal or common canalicular obstruction decreased gradually during the six-month follow-up period. In particular, patients undergoing procedures with experienced surgeons tended to show excellent surgical outcomes at the six-month follow-up exam.