Cadherin-13, a risk gene for ADHD and comorbid disorders, impacts GABAergic function in hippocampus and cognition.

Cadherin-13 (CDH13), a unique glycosylphosphatidylinositol-anchored member of the cadherin family of cell adhesion molecules, has been identified as a risk gene for attention-deficit/hyperactivity disorder (ADHD) and various comorbid neurodevelopmental and psychiatric conditions, including depression, substance abuse, autism spectrum disorder and violent behavior, while the mechanism whereby CDH13 dysfunction influences pathogenesis of neuropsychiatric disorders remains elusive. Here we explored the potential role of CDH13 in the inhibitory modulation of brain activity by investigating synaptic function of GABAergic interneurons. Cellular and subcellular distribution of CDH13 was analyzed in the murine hippocampus and a mouse model with a targeted inactivation of Cdh13 was generated to evaluate how CDH13 modulates synaptic activity of hippocampal interneurons and behavioral domains related to psychopathologic (endo)phenotypes. We show that CDH13 expression in the cornu ammonis (CA) region of the hippocampus is confined to distinct classes of interneurons. Specifically, CDH13 is expressed by numerous parvalbumin and somatostatin-expressing interneurons located in the stratum oriens, where it localizes to both the soma and the presynaptic compartment. Cdh13(-/-) mice show an increase in basal inhibitory, but not excitatory, synaptic transmission in CA1 pyramidal neurons. Associated with these alterations in hippocampal function, Cdh13(-/-) mice display deficits in learning and memory. Taken together, our results indicate that CDH13 is a negative regulator of inhibitory synapses in the hippocampus, and provide insights into how CDH13 dysfunction may contribute to the excitatory/inhibitory imbalance observed in neurodevelopmental disorders, such as ADHD and autism.

Eliminating smoking in bars, restaurants, and gaming clubs in California: BREATH, the California Smoke-Free Bar Program.

On January 1, 1998, California became the first state in the country to prohibit indoor smoking in nightspots, bars, bar/restaurant combinations, bingo parlors, cardrooms, and casinos on a statewide basis. This paper describes the activities which achieved this result, based on a program with three main goals: Ease the transition for business owners; Activate public support for the law; Defeat tobacco industry efforts to undermine the law. Important lessons learned from this campaign are presented.

Trichinosis: common source outbreak related to commercial pork.

Fifteen patients had trichinosis after eating raw or undercooked commercial pork sausage produced by a local processing plant. Even though it is recommended that all fresh pork be cooked to a temperature of at least 171 degrees F (77 degrees C) to ensure a sufficient margin of safety, this is not always done, and sporadic outbreaks continue to occur. Control strategies to prevent human trichinosis should include trichinosis surveillance of all commercial swine, as well as strict compliance with current regulations.

Dynamic and static lifting capacity and muscular strength of steelmill workers.

Dynamic and static strength measurements were compared respectively to maximal actual lifting and to a static lifting strength of 228 male steelmill workers. The strength tests were reasonably correlated with the lifting measurements. The dynamic strength test was the simplest, the least time consuming, revealing one to one ratio with the maximal actual lift and was not perceived as an exerting maneuver. Therefore, when matching between the job and a worker is desirable, it is suggested to use the dynamic strength test as a predictor for lifting capacity.

Physiological responses to resistance breathing during short and prolonged exercise.

Respirators which impose a resistance to breathing may cause a limitation in maximum exercise intensity. This limitation is of particular concern when respirators are used in emergency situations requiring high levels of exercise intensity. Many studies have defined the limitations of exercise intensity imposed by breathing resistance as the point where the subject feels "uncomfortable". Perhaps of greater importance is the true physiological limit. Using motivated subjects, the physiological limits of exercise intensity and related respiratory responses resistances of 11, 16, 25, 40, and 57 cm H2O pressure at a flow rate of 120 L.min-1 exercise limits were 72, 72, 79, 60, and 54 percent of maximum aerobic capacity (% VO2 max) for the short term and 58, 60, 49, 43, and 35% VO2max for the prolonged exercise (1 hour). The presence of significant external resistance to breathing was found to influence the traditional relationship between exercise intensity and duration.