The effects of ageing and exercise on skeletal muscle structure and function

Musculoskeletal ageing is associated with profound morphological and functional changes that increase fall risk and disease incidence and is characterised by age-related reductions in motor unit number and atrophy of muscle fibres, particularly type II fibres. Decrements in functional strength and power are relatively modest until the 6th decade, after which the rate of loss exponentially accelerates, particularly beyond the 8th decade of life. Physical activity is a therapeutic modality that can significantly attenuate age-related decline. The underlying signature of ageing, as manifested by perturbed redox homeostasis, leads to a blunting of acute and chronic redox regulated exercise adaptations. Impaired redox regulated exercise adaptations are mechanistically related to altered exercise-induced reactive oxygen and nitrogen species generation and a resultant failure to properly activate redox regulated signaling cascades. Despite the aforementioned specific impairment in redox signaling, exercise induces a plethora of beneficial effects, irrespective of age. There is, therefore, strong evidence for promoting regular physical exercise, especially progressive resistance training as a lifelong habitual practice

Short-Time Existence for Scale-Invariant Hamiltonian Waves

We prove short-time existence of smooth solutions for a class of nonlinear, and in general spatially nonlocal, Hamiltonian evolution equations that describe the self-interaction of weakly nonlinear scale-invariant waves. These equations include ones that describe weakly nonlinear hyperbolic surface waves, such as nonlinear Rayleigh wave

Interleukin 1 Signaling Is Regulated by Leukemia Inhibitory Factor (LIF) and Is Aberrant in Lif−/− Mouse Uterus

This study addresses the regulation of the interleukin 1 (IL1) system in the murine uterine luminal epithelium (LE) and stroma by leukemia inhibitory factor (LIF). Using RT-PCR we compared expression of Il1a, Il1b, Il1rn, Il1r1, and Il1r2 during the pre- and peri-implantation periods of pregnancy in wild-type (WT) and LIF-null LE and stroma. In WT LE, Il1a transcripts were down-regulated on Day 4 of pregnancy (D4), with renewed expression by the evening of D4 (D4 pm). In Lif−/− LE there was a gradual decrease in expression on D2, and expression became undetectable by D6. Il1b and Il1r1 expression were similar in WT and null mice, but Il1rn expression was almost completely lost during the peri-implantation period in Lif−/− LE. In the stroma, Il1a was sharply down-regulated on D4 and reappeared on D4 pm but was only expressed from D3 to D5 in the null mice. Stromal Il1r1 and Il1r2 were also misregulated. Il1rn showed constitutive expression in null stroma in contrast to the loss of expression on D4 in the WT mouse. In Lif-deficient mice, immunostaining indicated a reduction of endometrial IL1A at the time of implantation and of IL1B in stroma. LE-stromal coculture revealed that LIF stimulated the apical secretion of both IL1A and PTGES2 by LE cells without affecting basal secretion of IL1A and with only a small effect on basal PTGES2 secretion. We conclude that Il1a and Il1rn in LE and Il1a, Il1rn, and Il1r1 in stroma are regulated by LIF, which stimulates apical secretion of IL1A by LE

A Record of \u3ci\u3eNomada (Nomada) Colorata\u3c/i\u3e From Illinois With a Suggested Host Species (Hymenoptera: Apoidea)

(excerpt) Nomada colorata (Anthophoridae)was described by Mitchell (1962) on the basis of the holotype female from Michigan and two female paratypes from Michigan and New York

\u3ci\u3eAraphe Carolina\u3c/i\u3e in Illinois (Hemiptera: Largidae)

(excerpt) Araphe carolina (Herrich-Schaffer) is a little-known species that has been recorded from North Carolina south to Florida, thence west through Tennessee to Arizona and Baja California (Halstead, 1972). Froeschner (1944) characterized it as a scarce species in recording it from five counties in the Ozark Region of southern Missouri. The purpose of this note is to provide the first records of A. carolina in Illinois and incidentally to provide the first record of any largid bug in the state

\u3ci\u3eTriepeolus Mesillae\u3c/i\u3e (Hymenoptera: Apoidea) in Illinois: A Cleptoparasitic Bee New to the Eastern United States

(excerpt) Cockerell (Ann. Mag. Nat. Hist., Ser. 7, 13:33-42,1904) named Triepeolus mesillae on the basis of a series of specimens which he collected at Mesilla, New Mexico. A second locality for the species was added by Rozen (Amer. Mus. Novitates 2244, 1966) when he described the larva of T. mesillae from cells of Nomia (Epinomia) triangulifera Vacha! excavated by E. A

Effect of Domestic Effluent on Two Spring Surveys of Fishes in Lost Creek, Craighead County, Arkansas

Lost Creek is representative of deltonic streams of the St. Francis Basin possessing characteristics of being turbid. It has a low flow velocity except during the annual spring rains. Lost Creek meanders approximately 18 km. before receiving effluents and empties into Big Creek approximately 4 km. west of Jonesboro, Arkansas. Five collecting stations were studied in 1966 while six stations were sampled in 1970. Some fishes have been found to tolerate moderate amounts of domestic effluents and it is probable that the two species Lepomis cyanellus and Ictalurus melas, collected within the effluents, were more resistant than the other species of fish collected from Lost Creek