State University of New York System

About: State University of New York System is a education organization based out in Albany, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 54077 authors who have published 78070 publications receiving 2985160 citations.

Dynamics of synaptic vesicle fusion and membrane retrieval in synaptic terminals

Abstract: Communication among neurons occurs at specialized synaptic junctions, where neurotransmitter is released via calcium-dependent exocytosis from the synaptic terminal of the presynaptic cell onto the postsynaptic target neuron. Here we exploit the unique properties of giant synaptic terminals of bipolar neurons from goldfish retina to establish the kinetics and calcium-dependence of exocytosis, and the characteristics of membrane retrieval following secretion in presynaptic terminals. Simultaneous patch-clamp, calcium-indicator dye and time-resolved capacitance measurements reveal that activation of calcium current drives secretion at a rapid rate of about 10,000 vesicles per s and the calcium level necessary to drive secretion is locally greater than 50 microM. Two components of membrane retrieval were observed following secretory stimulation. After strong stimulation, capacitance returned to rest with a time constant of about 30 s, but after weaker stimuli recovery was much faster, with a time constant of about 2 s. Secretion in a vertebrate central nervous system neuron was thus found to differ substantially from that in other secretory cells in its rapid rate of vesicle fusion, requirement for high levels of intracellular calcium, and the high speed and completeness of membrane retrieval. These distinctive features reflect the specialization of neuronal synaptic terminals for rapid and focally directed release of neurotransmitter.

Research productivity and scholarly accomplishment of college teachers as related to their instructional effectiveness: A review and exploration

Abstract: This analysis reviews the research that has been done on the connection between research productivity or scholarly accomplishment of faculty members and their teaching effectiveness (as assessed by their students). On average, there is a very small positive association between the two variables. To understand this relationship better, extant research was explored for factors that might mediate either positive or inverse associations between research productivity and teaching effectiveness and those that possibly could be common causes of them. Pedagogical practices and dispositions of faculty members, as well as certain course or class characteristics (size of class, electivity of course), were examined as potential mediating factors. Potential common causes investigated were academic rank and age of faculty members, their general ability, their personality characteristics, and the amount of time or effort they spend on research activities. The association between research productivity and teaching effectiveness was explored further by considering whether its size and direction varies by career stage of faculty members, their academic discipline, and the type of college or university in which they teach.

Insulin resistance: definition and consequences.

Abstract: Insulin resistance is defined clinically as the inability of a known quantity of exogenous or endogenous insulin to increase glucose uptake and utilization in an individual as much as it does in a normal population. Insulin action is the consequence of insulin binding to its plasma membrane receptor and is transmitted through the cell by a series of protein-protein interactions. Two major cascades of protein-protein interactions mediate intracellular insulin action: one pathway is involved in regulating intermediary metabolism and the other plays a role in controlling growth processes and mitoses. The regulation of these two distinct pathways can be dissociated. Indeed, some data suggest that the pathway regulating intermediary metabolism is diminished in type 2 diabetes while that regulating growth processes and mitoses is normal.--Several mechanisms have been proposed as possible causes underlying the development of insulin resistance and the insulin resistance syndrome. These include: (1) genetic abnormalities of one or more proteins of the insulin action cascade (2) fetal malnutrition (3) increases in visceral adiposity. Insulin resistance occurs as part of a cluster of cardiovascular-metabolic abnormalities commonly referred to as "The Insulin Resistance Syndrome" or "The Metabolic Syndrome". This cluster of abnormalities may lead to the development of type 2 diabetes, accelerated atherosclerosis, hypertension or polycystic ovarian syndrome depending on the genetic background of the individual developing the insulin resistance.--In this context, we need to consider whether insulin resistance should be defined as a disease entity which needs to be diagnosed and treated with specific drugs to improve insulin action.