Postsynaptic expression of tetanus toxin light chain blocks synaptogenesis in Drosophila.

During the development of the nervous system embryonic neurons are incorporated into neural networks that underlie behaviour. For example, during embryogenesis in Drosophila, motor neurons in every body segment are wired into the circuitry that drives the simple peristaltic locomotion of the larva. Very little is known about the way in which the necessary central synapses are formed in such a network or how their properties are controlled. One possibility is that presynaptic and postsynaptic elements form relatively independently of each other. Alternatively, there might be an interaction between presynaptic and postsynaptic neurons that allows for adjustment and plasticity in the embryonic network. Here we have addressed this issue by analysing the role of synaptic transmission in the formation of synaptic inputs onto identified motorneurons as the locomotor circuitry is assembled in the Drosophila embryo. We targeted the expression of tetanus toxin light chain (TeTxLC) to single identified neurons using the GAL4 system. TeTxLC prevents the evoked release of neurotransmitter by enzymatically cleaving the synaptic-vesicle-associated protein neuronal-Synaptobrevin (n-Syb) [1]. Unexpectedly, we found that the cells that expressed TeTxLC, which were themselves incapable of evoked release, showed a dramatic reduction in synaptic input. We detected this reduction both electrophysiologically and ultrastructurally.     

Pre‐ and Postsurgery Behavioral Compliance,Patient Health,and Postbariatric Surgical Weight Loss

This study investigated the relationship between weight loss from gastric bypass surgery, patient characteristics, and compliance with physician instructions before and after surgery. A chart review of psychiatric and medical files was conducted for an initial cohort of 172 patients in a postsurgical management program. A total of 112 patients (primarily women (85%), white (79%), and well educated) from this cohort had presurgical data. Of these 112 subjects, 67 (60%) had postsurgical compliance information and BMI at 24 months postsurgery. The relationships between weight loss and a number of demographic, psychiatric, comorbid, and behavioral compliance factors were examined for these 67 patients. Missed appointments and noncompliance with exercise and weight loss plan instructions were high before and after surgery (65% vs. 72% for missed appointments, 39% vs. 51% for exercise, 42% vs. 57% for weight loss instructions). Although poor food choices were not frequently a problem before surgery (11%), they increased significantly after surgery: 37%, χ²(1) = 25.00, P < 0.001. Participants who lost the least weight at 2 years postsurgery were more likely to be nonwhite (r = 0.27, P = 0.039), have a lower socioeconomic status (SES) (r = 0.285, P = 0.02), and have a diagnosis of binge eating before surgery (r = 0.25, P = 0.039). Having more contact with patients and requiring adherence to behavioral changes, especially with respect to exercise and dietary restrictions, may improve the long‐term outcomes for bariatric procedures. In addition, those patients who are depressed and suffer from binge eating may need special attention from physicians during long‐term postoperative follow‐up.     

Diel patterns in singing activity of humpback whales in a winter breeding area in Okinawan (Ryukyuan) waters

Male humpback whales produce complex sounds known as songs during their breeding season. Previous studies have shown diel patterns of song in their breeding areas, but there had been no similar studies in the breeding area around Okinawa, Japan. To study diel patterns of song and the behavior of humpback whales in Okinawa, we conducted 24 hr recording with a fixed hydrophone in 2007, and vessel-based sighting surveys during 2014–2017. Song was monitored for 15 days, with peaks at sunrise and around 2200. Singing activity declined significantly between sunrise and sunset, then increased until 2200. Activity levels at night were higher and more stable than during the day. During 278 days of sighting surveys, 2,551 whales in 1,382 groups were observed. 79 individuals were confirmed as singers, all of which were lone whales. In six cases, singing individuals stopped singing before joining a group or began singing after leaving a group. Previous studies have shown that group size of humpback whales increases through the day. Considering the results from our study and the former studies, the decrease in singing activity as the day progresses may be a result of aggregation increasing, thus reducing the number of lone singers during the day.     

Plasmodium falciparum: detection of a novel asparagine-rich protein on the surface of sporozoite.

We had previously cloned and characterized a gene for a novel asparagine-rich protein from P. falciparum (PfARP), a target of natural human immune response. The antibodies to PfARP were localized to the surface of parasitized red blood cells and reacted with intracellular components in all erythrocytic asexual and sexual stages of the parasite. We here describe reactivity of antibodies against this novel PfARP on the surface of mosquito stage sporozoite of P. falciparum by indirect immunofluorescence assay and immunoelectron microscopy, the latter revealing a highly periodic punctate pattern of distribution of PfARP on the surface of sporozoite. These results suggest a possibility that PfARP might represent yet another sporozoite surface protein.     

Thromboxane synthase inhibition and cardiopulmonary function during endotoxemia in sheep.

We studied the cardiopulmonary response to endotoxin (lipopolysaccharide, LPS) in sheep with and without the administration of a thromboxane synthase inhibitor, OKY-046. The animals were instrumented for crystalographic dimension analysis of the left ventricle (LV) and for measurement of LV, aortic, left atrial, and pulmonary arterial pressures and cardiac index, as well as lung lymph flow. They received 1.0 micrograms/kg of Escherichia coli LPS with (n = 8) and without (n = 8) OKY-046 (10 mg/kg bolus, then 10 micrograms.kg-1.min-1). OKY-046 prevented the increase of pulmonary arterial pressure and the decrease of cardiac index that occurred during the early phase of endotoxemia. Between 8 and 12 h after LPS, cardiac index increased from 6.8 +/- 0.7 to 8.9 +/- 0.51.min-1.m-2. Concomitantly, the end-systolic pressure-diameter relationship (ESPDR, sensitive myocardial contractility index) significantly decreased from 14.7 +/- 0.6 to 7.7 +/- 0.7. Other indexes of the LV contractility (+dP/dtmax) were also reduced. OKY-046 prevented the decreases of ESPDR and +dP/dtmax. OKY-046 also attenuated the increased lung lymph flow changes seen with LPS.