Micturition

The lower urinary tract has two complementary functions. For the majority of the time it accepts and stores the urine excreted from the kidneys. It then expels the urine when required. In order to protect the kidneys the intravesical pressure needs to remain below that in the ureters during the storage phase. During the voiding phase the vesico-ureteric reflux has to be prevented and the bladder emptied completely. The anatomy of the lower urinary tract and in particular the neurological control mechanisms are vital in achieving these functions.     

Micturition

The lower urinary tract has two complementary functions. For the majority of the time it accepts and stores the urine excreted from the kidneys. It then expels the urine when required. In order to protect the kidneys the intravesical pressure needs to remain below that in the ureters during the storage phase. During the voiding phase the vesico-ureteric reflux has to be prevented and the bladder emptied completely. The anatomy of the lower urinary tract and in particular the neurological control mechanisms are vital in achieving these functions.     

Micturition

The lower urinary tract function is to store and void urine (micturition) that is produced by the kidneys and transferred via the ureters. The lower urinary tract consists of the bladder, urethra and (in males) the prostate. A complex interaction of central, autonomic and somatic innervation enables micturition to be under voluntary control. Common disorders of micturition include bladder outflow obstruction and overactive bladder syndrome, and management of these disorders may include conservative, pharmacological or surgical interventions.     

Micturition

The lower urinary tract function is to store and void urine (micturition) that has been produced by the kidneys and transferred to the bladder via the ureters. The lower urinary tract consists of the bladder, urethra and (in males) the prostate. A complex interaction of central, autonomic and somatic innervation enables micturition to be under voluntary control. Common disorders of micturition include bladder outflow obstruction and overactive bladder syndrome, and management of these disorders may include conservative, pharmacological or surgical interventions.     

Micturition disorders

This article reviews the psychological factors associated with micturition disorders and suggests that they may be causally linked to detrusor instability and sencory urgency. Patients with genuine stress incontinence have psychological profiles in keeping with a population who have a chronic physical disability. The treatment of patients with micturition disorders is reviewed and proposals are made for clinical management. The overall conclusion is that, in general, surgery and medication have little to offer whilst psychological treatments appear to be effective.     

Micturition Studies in Hypospadiacs

An evaluation of a total of 2 460 patients treated with exposure during the period 1962–1971. marked that the exposure method showed satisfactory results, but also that there are clear upper limits for the possibilities of this method. The approach of treatment was reconsidered and consequently very severely burned patients were excised acutely in the years 1972–1975. It was proved plausible, permissable and practically possible. On May 1, 1976, a randomized, controlled clinical trial commenced: Patients admitted for fresh burns were divided into groups: one group was unsuited for trial (U). (e.g. small children, electric burns etc.): of the remaining patients every even was treated with acute excision (A), (i.e. operation within 24 hours post burn), every odd patient according to the classical exposure method (E), employed by our unit: exposure followed by excision and transplantation of all unhealed burned areas no later than day 14 post burn. The results concerning mortality in the first 2-year material are presented. In the first year, which began a few months after moving from a 115 year old hospital into a quite new university hospital, the mortality is found to be twice as high as that found the second year. The reasons are the difficulties caused as a result of moving to new larger buildings, needing an increase of staff with two thirds, all of which are inexperienced in the care of burned patients. The mortality is exactly the same in the group treated with acute excision (A) as the group treated with exposure (E). The trial must continue and results of studies concerning morbidity will be published later.     

帕金森病致骨代谢异常的中枢机制研究进展

帕金森病(parkinson′s disease,PD)是老年人常见的神经退行性疾病。前期研究表明,PD患者比正常人更容易发生骨折。PD患者骨折风险的增加给家庭和社会带来沉重的负担,因此,阐明PD导致骨代谢异常的机制具有重大意义。近年来研究发现PD患者中枢肾素-血管紧张素系统(renin-angiotensin system,RAS)、下丘脑-垂体-肾上腺轴(hypothalamic-pituitary-adrenal axis,HPA)、交感神经系统(sympathetic nervous system,SNS)在骨代谢调节过程中发挥了重要作用。笔者拟从中枢机制的角度对PD相关的骨代谢异常进行总结与讨论。     

Micturition in comatose patients

The ability to void spontaneously was ascertained in 135 comatose patients, 76 per cent of whom emptied the bladder automatically as soon as the indwelling catheter could be removed. With additional treatment (bethanechol and/or intermittent catheterization), spontaneous micturition was achieved in all of the remaining patients. Elderly men had statistically more difficulties in becoming independent of an indwelling catheter.     

Micturition neuropharmacology

Applying the basic principles, therapy guides to our hypothetical cases can be constructed. The 60 year old man with postoperative abdominal perineal resection with hypertension and parkinsonism may well need a transurethral resection of the prostate; however, other options include decreasing his anticholinergic-type medications, such as antiparkinsonism medications, changing his hypertensive therapy from beta blockers such as propranolol and metoprolol to alpha blockers such as methyldopa and prazosin. Bethanacol would seldom be helpful alone, but with an alpha blocker could help if not contraindicated by the presence of vascular disease. The second example, a 45 year old woman with stress incontinence, may be assisted with improved storage by an anticholinergic agent, an alpha enhancer, a mucosal enhancer, and if pertinent, switching hypertensive therapy from an alpha blocker to a beta blocker. The last example, a T10 paraplegic with a spastic, hyperreflexic bladder, can have improved storage with anticholinergics, decreased sphincter tone with alpha blockers, as well as decreased sphincter tone with alpha blockers, as well as decreased spasms through suppression of hyperactive spinal cord activity with baclofen.     

Neurogenetics in Parkinson's disease

The pathogenesis of Parkinson's disease, a progressive degenerative disorder of the central nervous system, remains obscure. 20% of cases are familial. The disorder may be due to a combination of genetic and environmental factors. Some monogenic forms of Parkinson's disease have been described. Many genetic studies explore whether a candidate gene may confer an increased risk for this disease. The search for a genetic susceptibility may lead to establish a preventive therapy.     

Urodynamic findings in Parkinson's disease

Neurological evaluation was performed in 24 men and 5 women with Parkinson's disease who had persistent bladder symptoms. Detrusor hyperreflexia was found in 26 (90 per cent) of the patients. Sporadic involuntary electromyography activity of the external sphincter during involuntary detrusor contractions was encountered in 61 per cent but in none did this cause obstruction. Coordinated striated sphincter relaxation during voluntary detrusor contraction was found in 13 patients (45 per cent). Among 22 men who were in the prostatic disease age group only 4 (18 per cent) had definite prostatic obstruction. Moreover, none of 8 men with persistent symptoms after prostatectomy had evidence of bladder outlet obstruction.     

Neurourologic findings in Parkinson's disease

A total of 30 patients with an established diagnosis of Parkinson's disease and symptomatic voiding dysfunction underwent neurourologic evaluation. Detrusor hyperreflexia associated with appropriate sphincter relaxation was found to be the most common urodynamic pattern, occurring in 75 per cent of the cases. Two types of increased electromyogram activity at the time of detrusor contraction were identified: 1) pseudo-dyssynergia (7 per cent)--a voluntary contraction of the perineal floor in an attempt to prevent leakage and 2) sphincter bradykinesia (11 per cent)--a manifestation of skeletal muscle hypertonicity characteristic of parkinsonism. On the basis of these observations it is assumed that the effect of the basal ganglia on micturition is inhibitory in nature. The diagnostic and therapeutic approach to the parkinsonian patient with voiding dysfunction is discussed.     

Nerve-cell grafting in Parkinson's disease

The successful utilization of fetal nerve-cell grafts as therapeutic tools in animal models of neurodegenerative disease has prompted the first clinical attempts in parkinsonian patients in at least three countries. The extensive scientific data in rodents coupled with the first successful fetal neural grafts in monkeys with experimental parkinsonism suggest that consideration might now be given to clinical applications. Attention is also directed to the various types of donor cells that might be utilized in clinical trials for the treatment of parkinsonism, including potential benefits, risks, and limitations associated with each type of donor material. This review highlights major developments in this field as they relate to basic principles of neural grafting and discusses potential applications in humans.