Slip pulse and resonance of the Kathmandu basin during the 2015 Gorkha earthquake, Nepal.

Detailed geodetic imaging of earthquake ruptures enhances our understanding of earthquake physics and associated ground shaking. The 25 April 2015 moment magnitude 7.8 earthquake in Gorkha, Nepal was the first large continental megathrust rupture to have occurred beneath a high-rate (5-hertz) Global Positioning System (GPS) network. We used GPS and interferometric synthetic aperture radar data to model the earthquake rupture as a slip pulse ~20 kilometers in width, ~6 seconds in duration, and with a peak sliding velocity of 1.1 meters per second, which propagated toward the Kathmandu basin at ~3.3 kilometers per second over ~140 kilometers. The smooth slip onset, indicating a large (~5-meter) slip-weakening distance, caused moderate ground shaking at high frequencies (>1 hertz; peak ground acceleration, ~16% of Earth's gravity) and minimized damage to vernacular dwellings. Whole-basin resonance at a period of 4 to 5 seconds caused the collapse of tall structures, including cultural artifacts.

Variability of BOLD response evoked by foot vibrotactile stimulation: influence of vibration amplitude and stimulus waveform.

The aim of the present was study to evaluate cortical and subcortical neural responses on vibrotactile stimulation of the food and to assess somatosensory evoked BOLD responses in dependence of vibration amplitude and stimulus waveform. Sixteen healthy male subjects received vibrotactile stimulation at the sole of the right foot. The vibration stimulus was delivered through a moving magnet actuator system (MMAS). In an event-related design, a series of vibration stimuli with a duration of 1 s and a variable interstimulus interval was presented. Four stimulation conditions were realized using a 2 (amplitudes 0.4 mm or 1.6 mm) x 2 (waveform sinusoidal or amplitude modulated) factorial design. Stimulating with 0.4 mm amplitude compared to 1.6 mm stimulus amplitude more strongly activated the pre- and postcentral gyrus bilaterally and the right inferior, medial and middle frontal gyrus. In the reverse comparison significant differences were observed within the left inferior parietal lobule, the left superior temporal gyrus, and the left temporal transverse gyrus. In the comparison of sinusoidal versus modulated waveform and vice versa no significant activation differences were obtained. The inter-subject variability was high but when all four stimulation conditions were jointly analyzed, a significant activation of S1 was obtained for every single subject. This study demonstrated that the BOLD response is modulated by the amplitude but not by the waveform of vibrotactile stimulation. Despite high inter-individual variability, the stimulation yielded reliable results for S1 on the single-subject level. Therefore, our results suggest that vibrotactile testing could evolve into a clinical tool in functional neuroimaging.

Latent inhibition, but not prepulse inhibition, is reduced during withdrawal from an escalating dosage schedule of amphetamine.

The enhanced locomotor and stereotypic responses of the rat to repeated amphetamine (AMPH) administration are considered to be an animal model of positive schizophrenic symptoms. In contrast, behaviors observed during withdrawal from repeated AMPH are believed to model depression or anxiety. In the present study, the authors tested whether AMPH withdrawal might also elicit behaviors consistent with animal models of schizophrenia, specifically, disruptions in latent inhibition (LI) of 2-way active avoidance and prepulse inhibition (PPI) of startle. Rats treated with escalating doses of AMPH (6 days, 1-5 mg/kg ip) or saline were tested for LI and PPI during withdrawal. LI was eliminated by prior AMPH treatment in rats tested at 4, 13, and 28 days of withdrawal. In contrast, PPI did not differ between AMPH and control groups. These results support an interrelationship between repeated-AMPH and LI-disruption, but not PPI-disruption, models of schizophrenia.

Control of prolactin-secreting macroadenomas with parenteral, long-acting bromocriptine in 30 patients treated for up to 3 years.

OBJECTIVE: We investigated the effect of intramuscular injections of long-acting bromocriptine in patients with macroadenomas. STUDY DESIGN AND PATIENTS: Thirty patients with PRL-secreting pituitary macroadenomas were treated with repeated 4-weekly intramuscular injections of 50 or 100 mg of a long-acting, repeatable bromocriptine formulation for six to 37 injections, amounting to a total of 473 injections. Twenty patients received parenteral bromocriptine as primary therapy, ten had persisting hyperprolactinemia after previous therapies including pituitary surgery (n = 7), oral bromocriptine (7), and pituitary irradiation (2). MEASUREMENTS: A PRL day profile was obtained and the patients' clinical status and history were documented, at intervals. Detailed clinical, laboratory, and radiological (pituitary nuclear magnetic resonance or computed tomography scan) evaluations were performed at baseline, after 1 injection and every 6th injection thereafter. RESULTS: In all patients PRL was suppressed from a mean +/- SEM pretreatment level of 32,620 +/- 8680 to 4480 +/- 1140 mU/I on the third day after the first injection. In 12 patients PRL levels normalized (< 400 mU/I) with the first to fourth injection, in three additional patients PRL levels normalized after 8-15 months. In 19 patients PRL was suppressed to less than 1000 mU/l. In three patients PRL did not decrease to less than 50% of pretreatment; in two of them on oral bromocriptine prior to this study there had been a comparable low efficacy. Of 28 patients with macroadenomas (median height 22 mm) tumour shrinkage was evident in 15 by nuclear magnetic resonance or computed tomography scan 28 days after the first injection, and in three additional patients after 6 months. There was further regression in seven cases after 12, 18 or 24 injections. Adenoma size (mean +/- SEM) decreased to 66 +/- 7% of the pretreatment value. The 40 adverse events noted in 20 of 30 patients during 24 hours after the first injection were similar to known side-effects of oral bromocriptine, nausea and postural hypotension being the most frequent. With repeated injections, on average 0.6 adverse events were noted per injection (mostly mild asthenia). There were no local adverse reactions at the injection site. CONCLUSION: We conclude that long-acting repeatable bromocriptine in patients with macroprolactinomas offers a safe and efficacious primary treatment that ensures compliance and gives long-term control. Adverse reactions are comparable to oral bromocriptine but subside with repeated injections.