Mechanism of injury to the corpus callosum, with particular reference to the anatomical relationship between site of injury and adjacent brain structures

The location of corpus callosum injury was investigated using magnetic resonance imaging in 92 patients. The anatomical relationships in the region around the corpus callosum were also evaluated to clarify involvement in the mechanism of corpus callosum injury in 20 normal volunteers. Lesions in the posterior half of the corpus callosum accounted for 80% of corpus callosum injuries. The falx was increasingly elongated toward the posterior portion of the corpus callosum and the corpus callosum was thinnest at the body-splenium junction in the normal volunteers. The mechanism of corpus callosum injury apparently involves the following factors. The posterior half of the falx is closer to the corpus callosum than the anterior half. Therefore, the anterior part of the corpus callosum easily moves with lateral movement of the cerebral hemispheres, and the strain is likely to be concentrated in the posterior half of the corpus callosum, because the falx greatly limits lateral movement of the hemisphere in the posterior region. The corpus callosum is easily distorted at the thinnest part of the body-splenium junction. Therefore, corpus callosum injury predominantly occurs in the posterior half of the corpus callosum.     

Two circulatory routes within the human corpus cavernosum penis: a scanning electron microscopic study of corrosion casts

The microvascular architecture of the human corpus cavernosum penis was studied by scanning electron microscopy of vascular corrosion casts. The corpus cavernosum was supplied by the penile deep artery. It gave off branches to become either arteries distributed within the corpus cavernosum or those directly supplying the corpus spongiosum urethrae. The former arteries further divided into small arteries which fell into two categories: 1) arteries breaking up into capillaries, and 2) arteries draining directly into the cavernous sinuses. The capillaries were collected into venular networks just beneath the tunica albuginea (the subalbugineal venular plexus), while the cavernous sinuses were collected into venules at the periphery of the corpus cavernosum. These postcavernous venules also received venules from the subalbugineal venular plexus, and left the corpus cavernosum. Thus, two circulatory routes are evident within the corpus cavernosum. These findings suggested that the penile erectile cycle is controlled by hemodynamic changes between these two routes within the corpus cavernosum.     

Contraction and relaxation induced by some prostanoids in isolated human penile erectile tissue and cavernous artery

Contractant and relaxant effects of prostaglandins (PG) F2 alpha, E1 and E2, prostacyclin (PGI2), the thromboxane A2 agonist U46619 and the prostaglandin endoperoxide analogue U44069 were investigated in isolated preparations of the human corpus cavernosum, corpus spongiosum and cavernous artery. In corpus cavernosum and corpus spongiosum preparations, PGF2 alpha produced concentration-dependent contractions showing rhythmic variations in tension. The contractions were effectively relaxed by carbachol and vasoactive intestinal polypeptide. U46619, U44069 and PGI2 also contracted corpus cavernosum and corpus spongiosum strips at resting tension, U46619 being the most potent drug. PGE1 and PGE2, but not PGI2 relaxed corpus cavernosum and corpus spongiosum preparations contracted by noradrenaline (NA) and PGF2 alpha. PGE1 was the more effective agent; high concentrations of PGE2 produced contraction. In cavernous artery segments, PGF2 alpha produced concentration-dependent contractions. No oscillations in tension were observed; carbachol had no relaxant action, but VIP effectively relaxed the vessels. U46619 and U44069, but not PGI2 had contractant effects on cavernous artery segments at resting tension. PGE1 and PGI2, but not PGE2 relaxed NA contracted vessel preparations; all agents (PGE2 less effectively) relaxed PGF2 alpha contracted vessel segments. It is concluded that cavernous artery and erectile tissue proper (corpus cavernosum and corpus spongiosum) differ importantly in their reaction to various prostanoids. It cannot be excluded that products of the arachidonate cascade can be involved in the control of penile tumescence and erection.     

Corpus striatum and traumatic brain injury

The possibility of a subcortical syndrome differentially affecting memory in traumatic brian injury TBI subjects was examined. Magnetic resonance imaging scans of 46 traumatic brain injured male patients were compared with those of 34 male control subjects. Surface area measurements of the corpus striatum were calculated for both groups. Results demonstrated no significant differences in corpus striatum surface area measurements. Additionally, TBI patients were grouped according to severity of injury, as well as degree of corpus striatum atrophy, and neuropsychological outcome was examined. There were modest (r=0.35) but significant correlations between corpus striatum degeneration and the delayed recall trial and total score of the Rey Auditory Verbal Learning Test, but no other correlations between neuropsychological and corpus striatal surface area were significant. Because subcortical pathology may have a differential effect on memory, recognition and recall memory were further analysed, but no significant differences were found. TBI subjects with the smallest corpus striatum values did not test significantly different from TBI patients with normal corpus striatum values or differences in cortical atrophy, as determined by a ventricle to brain ratio. These findings suggest that there is not a unique pattern of subcortical pathology involving the corpus striatum in TBI.     

激肽释放酶激肽系统在大鼠阴茎海绵体表达的研究

目的:研究激肽释放酶激肽系统在成年大鼠阴茎海绵体的表达。方法:利用逆转录聚合酶链反应(RTPCR)技术分别检测SD大鼠阴茎和心脏组织中组织型激肽释放酶Ⅰ和激肽B2型受体mRNA的表达情况。结果:大鼠心脏与阴茎海绵体组织中均表达组织型激肽释放酶Ⅰ和激肽B2型受体mRNA,两者有几乎相同的表达水平,差异无显著性(P>0.05)。结论:在生理状态下,激肽释放酶激肽系统存在于阴茎海绵体组织中,而且与心血管系统的表达水平相当。     

Misoprostol induces relaxation of human corpus cavernosum smooth muscle: comparison to prostaglandin E1

Prostaglandin E1 (PGE1) relaxes trabecular smooth muscle by interacting with specific G-protein coupled receptors on human corpus cavernosum smooth muscle and increasing intracellular synthesis of cAMP. Misoprostol (Cytotec), is an oral prostaglandin E analogue. The purpose of this study was to compare the functional activity of misoprostol with PGE1 in human corpus cavernosum and cultured human corpus cavernosum smooth muscle cells. Misoprostol, misoprostol free acid or PGE1 induced dose-dependent relaxations in strips of human corpus cavernosum. At concentrations greater than 10(-6) M, tissue recontraction was observed with all three agents. This was abrogated by pretreatment with the thromboxane A2 receptor antagonist SQ29,548. From these observations, we conclude that misoprostol is activated by human corpus cavernosum in situ and relaxes phenylephrine-precontrated tissue strips in vitro. This relaxation response is mediated by the increased cAMP synthesis by these agents.     

Leiomyoma of the corpus cavernosum of the penis

While soft tissue tumors can occur in the penis, corpus cavernous tumors are rare. Reported cases of corpus cavernous tumors are from metastases of advanced malignancy, such as cancers of the bladder, prostate, rectosigmoid colon, kidney, pancreas, liver, testis and nasopharynx. Primary corpus cavernous tumors are extremely rare and have possibly never been reported before. Herein, we report a case of leiomyoma of the corpus cavernosum. After the diagnosis of leiomyoma was established, total excision of the tumor was not attempted and the tumor remained unchanged in size and shape over a follow-up period of 15 months.     

Anatomical branches of the superior rectal artery in the distal rectum

Objective  The aim of this experimental study was to study the arterial supply of the corpus cavernosum recti in the inner wall of the distal rectum in relation to haemorrhoidal ligation therapy.
Method  In 10 nonfixed human cadavers, the arterial vasculature of the rectum was studied using the Araldite casting method. Subsequently, the specimens were treated with methylbenzoate in order to obtain semitransparent specimens in which the corpus cavernosum recti could be studied.
Results  Specimens were obtained permitting study of the arterial vasculature of the rectum and corpus cavernosum recti at all levels. The superior rectal artery was found to supply the corpus cavernosum recti which consisted of a variable number of equally spaced twisting arteries.
Conclusion  The distal rectum is supplied by the superior rectal artery. The supplying arteries of the corpus cavernosum recti are not confined to the strict locations described in the literature. This finding is of importance in surgical treatment of haemorrhoidal disease.     

Human penile hemodynamics studied by a polarographic method

Observations of the tissue oxygen tension alteration were made using an open tip type oxygen electrode polarographic method as an index of blood flow change in the penile skin, corpus cavernosum and thigh skin of 16 males aged 20-26 years (average age: 20.5 years). In another five males aged 18-21 (average age: 19.8 years) the relationship between corpus cavernosum tissue oxygen tension alteration and penile circumference change in the erection process was observed. This relation was obtained in the penile circulation model, and penile hemodynamics were ascertained. In the flaccid penis the corpus cavernosum contains low-oxygen blood and there is a blockade at the vascular tree in the corpus cavernosum. In the tumescence phase the blood flow of the corpus cavernosum increased suddenly by the relief of cavernosum vascular blockade. During the penile tumescence phase the increased inflow and outflow persisted in corpus cavernosum, and in penile skin the blood also increased initially, but gradually decreased as penile circumference increased. After erection was attained it is thought that resistance to inflow occurred by outflow pathway contraction. In the detumescence phase, a decrease of inflow and a concomitant increase of outflow occurred and the reopening of outflow is thought to be necessary for prompt penile detumescence.     

Effects of integrin‐linked kinase on human corpus cavernosum smooth muscle cell cytoskeletal organisation

We investigated the effects of integrin‐linked kinase (ILK) on the in vitro attachment, spreading, migration and microfilament dynamics of human corpus cavernosum smooth muscle cells. ILK small interfering RNA (siRNA) was used to transfect human corpus cavernosum smooth muscle cells; and cell attachment, spreading and migration were assessed. Additionally, microfilament dynamics were evaluated using Alexa Fluor 488 and phalloidin staining. We found that ILK gene knock‐down significantly inhibited human corpus cavernosum smooth muscle cell attachment, spreading and migration. Moreover, blocking the expression of ILK disturbed actin cytoskeleton reorganisation and morphology in human corpus cavernosum smooth muscle cells. These results show that the targeting of ILK with siRNA significantly inhibited cell attachment, spreading, migration and microfilament dynamics in human corpus cavernosum smooth muscle cells. These findings indicate that ILK might be a potential therapeutic molecular target for the treatment of erectile dysfunction.     

A canine model for hemodynamic study of isolated corpus cavernosum

We developed a canine model which permits hemodynamic study of the isolated corpus cavernosum. The arterial and venous flow to the corpus cavernosum was measured and pressure was measured in each corpus cavernosum separately. To provide controlled inflow to the corpora, each side was perfused separately with the aorta clamped. It was demonstrated that arterial and nerve supply to the corpus cavernosum is crossed. During unstimulated corporal perfusion, venous outflow from the corpora increased with increased perfusion rate up to a maximum of 40 ml./min. Following pelvic nerve stimulation, intracorporal pressure increased at much lower rates of perfusion. Moreover, it was noted that intracorporal pressure was not transmitted from one side to the other. Thus, in the canine model, each corpus cavernosum may act as a control for the contralateral one. The technique we used to measure venous outflow from the corpora cavernosa, previously undescribed, permits accurate depiction of the hemodynamics of penile erection.     

计算机辅助分析人、家兔、大鼠和小鼠附睾精子运动能力

本研究应用计算机辅助精子分析（ＣＡＳＡ）定量分析了人、家兔、大鼠和小鼠精子附睾成熟过程中，精子运动能力的发生和发展。同时对这几种动物和人进行了系统分析和比较。结果表明：在不同种属之间，其运动的发生和发展具有一定的差异；各种不同种属动物精子在各自附睾成熟过程中，其运动能力的两个方面参数，运动速度和运动方式的发展是不平行的；附睾尾部精子的运动能力（包括运动速度和直线程度）最强。     

Fiber connections between the cerebral cortex and the corpus callosum in Alzheimer's disease: a diffusion tensor imaging and voxel-based morphometry study

Regional cortical atrophy in Alzheimer's disease (AD) most likely reflects the loss of cortical neurons. Several diffusion tensor imaging studies reported reduced fractional anisotropy (FA) in the corpus callosum in AD. The aim of this study was to investigate the association between reduced FA in the corpus callosum and gray matter atrophy in AD. Thirteen patients with AD with a mean (+/-standard deviation) age of 68.3 years (+/-11.5) and mean Mini Mental State Examination (MMSE) score of 21.8 (+/-4.8) were recruited. There were 13 control subjects with a mean age of 66.7 years (+/-6.4) and MMSE of 29.1 (+/-0.7). We used voxel-based morphometry of gray matter maps and region of interest-based analysis of FA in the corpus callosum. FA values of the anterior corpus callosum in AD patients were significantly correlated with gray matter volume in the prefrontal cortex and left parietal lobes. FA values of the posterior corpus callosum were significantly correlated with gray matter volume in the bilateral frontal, temporal, right parietal, and occipital lobes. In control subjects, no correlations were detected. Our findings suggest that decline of FA in the corpus callosum may be related to neuronal degeneration in corresponding cortical areas.     

Hemodynamics of canine corpora cavernosa during erection

Being able to induce erection by electrical stimulation of the cavernous nerves, we studied the hemodynamics of canine penile erection. Simultaneous recording of flow and pressure of the internal pudendal artery as well as pressure within the corpus cavernosum clearly demonstrated that increase of arterial flow preceded corporeal pressure increase. When saline was infused directly into the corpus cavernosum, with the aorta clamped, decreasing venous flow during erection could be demonstrated. Tumescence of the corpus cavernosum was found to be a result of active relaxation of sinusoidal spaces, active arteriolar dilatation, and active venous constriction. At full erection, there was still flow into and out of the corpus cavernosum, although it was reduced to only a fraction of a milliliter per minute.     

大鼠精子在附睾成熟过程中肉毒碱量变化的研究

肉毒碱被认为是与精子在附睾中成熟有关的成熟因子。本文报告测定大鼠附睾头部,体部及尾部精子中的肉毒碱。结果表明精子在循附睾头、体、尾运行过程中,精子中肉毒碱含量逐步增加,在附睾体一头部,附睾尾一头部的精子内的肉毒碱量呈现十分显著性差异。结果提示附睾体部或体一头部交界部位可能是精子在附睾中成熟的关键部位。     

内源性一氧化碳对离体犬阴茎海绵体平滑肌的作用

目的:探讨内源性一氧化碳(CO)对离体犬阴茎海绵体平滑肌作用的影响。方法:利用水浴条件下阴茎海绵体肌条的张力测定技术,用CO合成的关键酶血红素氧合酶(HO)的诱导剂———氯高铁血红素诱导海绵体平滑肌生成内源性CO,观察CO对去氧肾上腺素(PE)诱导收缩的阴茎海绵体肌条作用的影响。结果:氯高铁血红素对10μmol/L PE诱导的肌条收缩具有浓度依赖性的松弛作用,10~100μmol/L氯高铁血红素对平滑肌肌条的松弛效应与空白对照相比明显升高(P<0.01)。用锌原卟啉-Ⅸ(ZnPP-Ⅸ)或亚甲蓝孵育处理后的肌条,氯高铁血红素的舒张作用明显减弱(P<0.01)。结论:内源性CO具有浓度依赖性松弛阴茎海绵体平滑肌的作用,其机制可能是通过CO环磷酸鸟苷途径作用所致。     

Role of epididymis in sperm maturation

One hundred ninety patients with obstructive azoospermia caused by bilateral epididymal blockage have been followed up for four years or longer after undergoing "specific tubule" vasoepididymostomy. When anastomosis was required in the corpus epididymis, the "patency" rate was 78 percent, and the overall pregnancy rate was 56 percent. The pregnancy rate for "patent" cases was 72 percent, indicating that a high fertility rate can be obtained with sperm that have not transited the full length of corpus epididymis. By contrast, with vasoepididymostomy to the caput epididymis there was a 73 percent "patency" rate, but the overall pregnancy rate was only 31 percent. The pregnancy rate for "patent" cases was 43 percent. Sperm from the corpus epididymis have a higher rate of fertility than sperm from the caput epididymis, but sperm from proximal areas of the corpus have no less fertility than sperm from the distal corpus epididymis. The most remarkable observation is that in almost half the cases sperm that have never journeyed beyond the caput epididymis seem to be capable of causing pregnancy.     

Androgen binding activity in the spongy tissue of mammalian penis

The binding of [3H]R1881 to cytosol fractions was determined for the spongy tissues of horse, porcine and human penis. Binding of [3H]R1881 to cytosol fractions from these spongy tissues was found to be specific with high affinities (mean of Kd; 1.8 X 10(-10) M) but with equally low binding capacities (mean of 4.66 fmol/mg. protein). Saturation analysis revealed that the binding capacity was similar for both corpus cavernosum and corpus spongiosum of horse penis. We conclude that a trace amount of androgen receptor is present in spongy tissue of the penis and that there is no difference in cytosolic receptors between corpus cavernosum and corpus spongiosum in adult mammalian penis.     

腹腔镜下输卵管妊娠保守性手术中剥除妊娠黄体对预防持续性异位妊娠的效果探讨

目的探讨腹腔镜下输卵管妊娠保守性手术同时行妊娠黄体剥除对预防持续性异位妊娠的临床效果。方法2006年1月～2008年12月对142例输卵管妊娠施行腹腔镜下保守性手术,术中同时行黄体剥除77例(A组),未行黄体剥除65例(B组),评价2种术式的治疗效果。结果A组手术时间(40±16)min与B组(35±15)min比较差异无显著性(t=1.909,P=0.058);A组术中出血量(50±30)ml与B组(48±30)ml比较差异无显著性(t=0.396,P=0.693);A组血β-hCG降至正常时间(12±2)d显著短于B组(21±7)d(t=-10.656,P=0.000);A组持续性异位妊娠发生率1.3%(1/77)显著低于B组12.3%(8/65)(χ2=5.461,P=0.019)。结论腹腔镜下输卵管妊娠保守性手术同时行妊娠黄体剥除有利于清除残余滋养细胞,使血β-hCG值下降,是预防持续性异位妊娠发生的另一种术式选择。     

Autonomic control and vascular changes during penile erection in monkeys

The mean pressure in the unstimulated corpus cavernosum of monkeys was 12.1 mm Hg. Pelvic nerve stimulation at 8 to 10 Hz produced penile extension and the mean pressure increased to 64.3 mm Hg (47-84% of carotid artery pressure) after a latency of 10 s. On stopping stimulation, recovery to resting levels occurred within 2 min. The response was not blocked by atropine or propranolol. Blood flow through two 19 gauge needles inserted into the corpus cavernosum increased in parallel with the pressure changes, indicating that arterial inflow increased. Stimulation of either hypogastric nerves or the sympathetic chain produced penile retraction but increased corpus cavernosal pressure. The response to pelvic nerve stimulation was partially blocked. It was concluded that both of these nerves contract penile erectile tissue within the corpus cavernosum and constrict arterial inflow.