The myometrium is the middle layer of the uterine wall, consisting of uterine smooth muscle cells, but of supporting stromal and vascular tissue. Its main function is to induce uterine contractions; the myometrium is located between the endometrium, the serosa or perimetrium. Myometrium has 3 layers: outer longitudinal smooth muscles, middle crisscrossing muscle fibres, inner circular fibres. Middle crisscross fibres act as living ligature during involution of the uterus and prevent blood loss; the inner one-third of the myometrium appears to be derived from the Müllerian duct, while the outer, more predominant layer of the myometrium appears to originate from non-Müllerian tissue, is the major contractile tissue during parturition and abortion. The junctional layer appears to function like a circular muscle layer, capable of peristaltic and anti-peristaltic activity, equivalent to the muscular layer of the intestines; the molecular structure of the smooth muscle of myometrium is similar to that of smooth muscle in other sites of the body, with myosin and actin being the predominant proteins.
In uterine smooth muscle, there is 6-fold more actin than myosin. A shift in the myosin expression of the uterine smooth muscle may be responsible for changes in the directions of uterine contractions during the menstrual cycle; the myometrium stretches during pregnancy to allow for the uterus to become several times its non-gravid size, contracts in a coordinated fashion, via a positive feedback effect on the "Ferguson reflex", during the process of labor. After delivery the myometrium contracts to expel the placenta, crisscrossing fibres of middle layer compress the blood vessels to minimize blood loss. A positive benefit to early breastfeeding is a stimulation of this reflex to reduce further blood loss and facilitate a swift return to prepregnancy uterine and abdominal muscle tone. Uterine smooth muscle has a phasic pattern, shifting between a contractile pattern and maintenance of a resting tone with discrete, intermittent contractions of varying frequency and duration; as noted for the macrostructure of uterine smooth muscle, the junctional layer appears be capable of both peristaltic and anti-peristaltic activity.
The resting membrane potential of uterine smooth muscle has been recorded to be between -35 and -80 mV. As with the resting membrane potential of other cell types, it is maintained by a Na+/K+ pump that causes a higher concentration of Na+ ions in the extracellular space than in the intracellular space, a higher concentration of K+ ions in the intracellular space than in the extracellular space. Subsequently, having K+ channels open to a higher degree than Na+ channels results in an overall efflux of positive ions, resulting in a negative potential; this resting potential undergoes rhythmic oscillations, which have been termed slow waves, reflect intrinsic activity of slow wave potentials. These slow waves are caused by changes in the distribution of Ca2+, Na+, K+ and Cl− ions between the intracellular and extracellular spaces, which, in turn, reflects the permeability of the plasma membrane to each of those ions. K+ is the major ion responsible for such changes in ion flux, reflecting changes in various K+ channels.
The excitation-contraction coupling of uterine smooth muscle is very similar to that of other smooth muscle in general, with intracellular increase in calcium leading to contraction. However, the stimulating factors for uterine smooth muscle differs from other types of muscles in the body. Removal of Ca2+ after contraction induces relaxation of the smooth muscle, restores the molecular structure of the sarcoplasmic reticulum for the next contractile stimulus. Lack of contraction at this stage is termed uterine atony. After pregnancy the uterus returns to its nonpregnant size by a process of myometrial involution. Benign neoplasms of the myometrium are common, termed uterine leiomyomata or fibroids, their malignant version, leiomyosarcoma, is rare
Coerced abstinence is a drug rehabilitation strategy which uses frequent monitoring and immediate punishment to reduce drug use among participants. This strategy can reduce recidivism rates among chronic drug users those on probation and parole. Most probation agreements mandate drug treatment, but a coerced abstinence program mandates only abstinence, enforced through regular, predictable drug testing. Under this system, failed tests swiftly result in a brief period of incarceration - for a few days; this policy option is advocated by a crime policy expert Mark A. R. Kleiman. Most drug courts require defendants to attend drug treatment and to return to court periodically and report progress to a judge; the extent of progress influences sentencing. These programs are not available to serious offenders. Drug court programs place as much emphasis on program attendance; because these programs have limited resources and the focus is treatment rather than abstinence, many in treatment can estimate the likelihood of being tested and choose to take the risk of continued use.
Although the penalty for getting caught is quite high, the chances of being tested are quite low. Behavior in the face of risks tends to follow. According to Prospect Theory, coerced abstinence is effective at getting people off drugs because the frequency and certainty of a sentence is a much more significant deterrent than severity of the sentence. In other words, if every time probationers fail a drug test, they go to jail probationers will use less drugs than if they are only caught if the penalty is higher. One problem with implementing a coerced abstinence program is that the scope of the program must be sufficiently small to track down those who do not show up for tests. Probation officers are overworked and police do not make warrant service a high priority. Designing a good program is quite difficult since sanctions must be sure. Another problem with coerced abstinence is the political feasibility; because the program ascribes neither to the disease model of addiction nor to a moral-model, it may be too ideologically neutral to be a successful part of a political platform.
The Hawaii State Judiciary has implemented a probation program which relies on the theory of coerced abstinence called H. O. P. E.. The program has achieved promising results among paroles with a history of methamphetamine use and inspired other pilot programs in the United States. Evaluations of H. O. P. E. Indicate that participants spend on average 130 fewer days in prison than participants in traditional community supervision programs. Sober Coach Sober living environment Drug policy of the Soviet Union Psychology Hawaii State Judiciary's "About Hope" Page Alpha Treatment Center Friends of Hope Forced Abstinence Model of Relapse to Study Pharmacological Treatments of Substance Use Disorder
Brad Voth is a Canadian former professional ice hockey player. Voth played junior hockey with the Medicine Hat Tigers in the Western Hockey League from 1996 to 2001. In the 1998 NHL Entry Draft he was selected 157th overall in the 6th round by St. Louis Blues, he spent two season with the Blues organization, playing for their American Hockey League affiliate the Worcester IceCats and their ECHL affiliate the Peoria Rivermen. After being released by the Blues in 2003, Voth spent a further two seasons in the ECHL, spending the 2003-04 season with the Columbus Cottonmouths and the 2004-05 season with the Texas Wildcatters. In 2005, Voth moved to the United Kingdom and signed for the Cardiff Devils of the Elite Ice Hockey League. An imposing figure at 6'5” and 235 lbs, Voth played tough hockey, in a style not always seen in the EIHL, his role in the Cardiff Devils was an enforcer, demonstrated by his significant penalty minutes totals during his stint, a total 1,762 in 300 EIHL league games and was the EIHL's Most Penalised Player four out of his five years in the league.
However, Voth was an offensive presence within the team scoring 209 points for the Devils. His standout season was the 2007-08 season, when he scored 24 goals and 16 assists for 40 points in 50 games, he was named captain of the team in January 2007 and held it for three years before being relieved of it in February 2010. Voth sustained a nerve injury in a game against the Belfast Giants in December 2011 and sat out for several weeks until 4 February 2012 when Cardiff announced that Voth would retire with immediate effect and would begin work with the Fire Service. Following his retirement, his jersey number #26 was retired by the Devils. 2005-06 EIHL Challenge Cup 2006-07 British Knockout Cup Brad Voth career statistics at EliteProspects.com Brad Voth career statistics at The Internet Hockey Database