Stage-dependent topographical relationship of spermatogonia and early spermatocytes to Sertoli-Sertoli interspaces in the rat testis

In the rat seminiferous epithelium the Sertoli-Sertoli interspaces can be regarded as ending at the surface of basal germ cells as well as at the basement membrane. The relationship between these basal endings (BEs) of the Sertoli-Sertoli interspaces and the basal germ cells was examined using the electron microscope. The number of BEs in a given area of the seminiferous epithelium was counted and found to be constant throughout the cycle of the seminiferous epithelium. Undifferentiated spermatogonia had contact with very few BEs while differentiating type A spermatogonia at stage VII and later during the cycle seemed to be associated with a maximum of BEs. As type A spermatogonia developed to intermediate spermatogonia, type B spermatogonia, and preleptotene spermatocytes, the average number of BEs per cell decreased exponentially. Thin, fingerlike cell projections emerged from the differentiating type A and intermediate spermatogonia along the basement membrane. These projections were associated with BEs. It is concluded that a specific stage-dependent topographical arrangement is established between Sertoli cells and germ cells long before the first synchronous division of type A spermatogonia takes place. The significance of this arrangement is discussed.     

Administration of noradrenaline in the autonomic ganglia modifies the testosterone release from the testis using an ex vivo system

The male gonad receives nerve fibres from the autonomic ganglionic system. These fibres converge on the testis along two pathways, the superior and the inferior spermatic nerves. The superior spermatic nerve runs from the superior mesenteric ganglion alongside the testicular artery, whereas the inferior spermatic nerve originates in inferior mesenteric ganglion, accompanies the vas deferens and penetrates the inferior pole of the testis. The aim of this work was to evaluate androgen release after the addition of noradrenaline or adrenoreceptor antagonists (propranolol or phentolamine) to the ganglionic compartment. An ex vivo system used in a previous work was incubated in two separate containers, one for the testis and the other for the ganglion. Both organs remain interconnected (as in vivo) by the respective spermatic nerve. When noradrenaline was added to the inferior mesenteric ganglion, testosterone release in the gonad container underwent a progressive and significant increment. Propranolol diminishes and phentolamine increases the androgen release. When using the superior mesenteric ganglion, no changes were observed. These results indicate that the ganglionic stimulation of the autonomic system clearly participates in testosterone release from the testis. This effect depends on the ganglion involved. These results make it evident that not only the classical and well-known hypothalamus–hypophysial axis, but also the peripheral nervous system, via the autonomic ganglia, are directly involved in the endocrine control of the testis.     

The effects of a selective noradrenaline reuptake inhibitor on the urethra: an in vitro and in vivo study

OBJECTIVE: To identify the effects of a selective noradrenaline reuptake inhibitor (venlafaxine) on urethral perfusion pressure (UPP) in rabbits and rats, and thus assess its therapeutic potential for treating stress urinary incontinence. MATERIALS AND METHODS: Strips of bladder and proximal urethra were prepared from female New Zealand White rabbits. Each strip was electrically stimulated and the contractile responses of controls strips compared with those after pretreatment with venlafaxine (100 micromol/L). In separate experiments using 80 adult female Sprague-Dawley rats (250-300 g), changes in intravesical pressure and UPP after the intra-arterial and intra-urethral administration of phenylephrine, phentolamine, fluoxetine and venlafaxine were monitored using double-lumen catheters. RESULTS: Pretreatment with venlafaxine significantly decreased the contraction of bladder strips (P=0.01) and significantly increased the contraction of urethral strips (P=0.008). In vivo, phenylephrine administered by both routes significantly increased UPP (P=0.02); phentolamine (arterial) significantly decreased UPP (P=0.001); fluoxetine (arterial) had no effect on UPP, and venlafaxine (both routes) significantly increased UPP (both P<0.001). The intravesical pressure was not changed significantly in any animal. CONCLUSIONS: Venlafaxine effectively increased UPP both in vitro and in vivo; these results imply that venlafaxine may be useful for treating stress urinary incontinence, by increasing the UPP.     

Imaging of small vessels using photoacoustics: an in vivo study

BACKGROUND AND OBJECTIVES: The ability to correctly visualize the architectural arrangement of microvasculature is valuable to many diverse fields in medicine. In this study, we applied photoacoustics (PA) to obtain high-resolution images of submillimeter blood vessels. STUDY DESIGN/MATERIALS AND METHODS: Short laser pulses are used to generate ultrasound from superficial blood vessels in several animal models. From these ultrasound waves the interior of blood vessels can be reconstructed. RESULTS: We present results from a novel approach based on the PA principle that allows specific in vivo visualization of dermal blood vessels without the use of contrast agents or ionizing radiation. CONCLUSIONS: We show PA images of externalized blood vessels and demonstrate in vivo PA imaging of vasculature through layers of skin varying in thickness.     

Revascularization of the testis using a vascular induction technique: a potential approach for staged orchiopexy in high-undescended testis

The present study was designed to determine whether a fasciovascular flap as a vascular carrier could be used to revascularize the undescended testis for avoiding the hazardous effects of the Fowler-Stephens procedure, high division of the spermatic vessels, and for bringing high-undescended testes into the scrotum. A total of 25 Wistar rats were divided into five groups of five rats each. In each group, surgical procedures were performed bilaterally, i.e. ten testes in each group, as follows: sham-operated controls (group 1), undescended testes (group 2), high division of the spermatic vessels (group 3), vascular induction with immediate division of spermatic vessels (group 4), and with delayed division of spermatic vessels (group 5). Evaluations were done by measuring the testicular weight and volume, testicular blood flow, and testicular biopsy scores and by microangiography. A moderate to severe decrease in testicular weight and volume in all experimental groups was observed compared with the sham-operated controls (group 1), but this was significantly less in groups 2 and 5. High division of the spermatic vessels in groups 3 and 4 resulted in a significantly greater decrease in the testicular blood flow, but this did not occur in group 5. Microangiographically, an impaired vascular supply from the deferential artery in group 3 and insufficient revascularization from the fasciovascular carrier in group 4 were observed. However, efficient revascularization stemming from the superficial epigastric artery of the fasciovascular flap was found in group 5. The testicular biopsy scores of groups 2 and 5 were significantly greater than those of groups 3 and 4. The results of the present study demonstrate that the fasciovascular flap as a vascular carrier revascularizes the testis through spermatic vessels after delayed division and provides an adjuvant treatment modality or first-stage procedure in a salvage operation for high-undescended testis during staged orchiopexy.Presented at the 10th Japan Society of Plastic and Reconstructive Surgery Research Council Meeting, October 18–19, 2001, Tokyo, Japan.     

Combined endovascular and neurosurgical approach to the removal of an intraaortic pedicle screw

Iatrogenic aortic injuries are a potentially devastating complication of spine surgery. In instrumented cases, injuries may occur in the perioperative period due to iatrogenic vessel injury, or they may occur years later as prominent implants erode or penetrate major vessels. The authors present a case of a 71-year-old man in whom a thoracic pedicle screw was found perforating the thoracic aorta during routine follow-up 6 months after surgery. Due to the risk of future complications, the screw was removed while simultaneously delivering an endovascular aortic stent to gain vascular control. Surgical considerations and potential technical limitations are discussed.     

高浓度乙酸注射治疗兔VX2肝肿瘤的实验研究

目的利用兔VX2肝移植瘤模型探讨高浓度乙酸注射治疗肝肿瘤的价值,并探索注射治疗肝肿瘤的最适乙酸浓度.方法用移植法建立兔VX2肝肿瘤模型,将40只携瘤兔随机分为A、B、C、D四组.术前以CT测量肿瘤直径.开腹向A、B、C、D组肝肿瘤内分别注入50%、75%、100%乙酸和生理盐水,48 h后重复注射一次,术后一周处死兔子取肝脏观测比较各组肿瘤体积改变情况及坏死灶周围新生灶情况,并取肿瘤组织制作石蜡切片(HE染色),镜下观察肿瘤组织坏死情况.结果注射后一周各实验组肿瘤直径均减小,对照组肿瘤直径明显增大.100%乙酸组10例仅1例在坏死灶周围发现新生灶,而50%乙酸组发现5例,75%乙酸组发现7例.镜下显示100%乙酸组肿瘤中未坏死的肿瘤细胞团较75%和50%乙酸组少见.结论高浓度的乙酸对兔VX2肝肿瘤的灭活效果显著;其中100%的乙酸效果最佳.     

The precochlear approach to the anterior petrous apex: an anatomic study

The petrous apex is the most inaccessible portion of the temporal bone and surgical exposure presents considerable challenge. The transmastoid precochlear approach offers a direct intra temporal route to this region, providing good visual exposure with cochlea preservation. An anatomic study of 20 human temporal bones was performed to delineate the landmarks for this approach. Measurements to the tegmen tympani, carotid artery, and the anterior-superior limit of the cochlea were made from the cochleariform process, a constant landmark in the middle ear. Distances to the tegmen averaged 5.4 mm (range: 3.5-9 mm), to the carotid artery 9.3 mm (8-11 mm), and the cochlea 3.1 mm (2-5 mm). The entry to the apex admitted an average burr size of 3.5 mm (2-7 mm). We anticipate this approach will prove useful in the treatment of benign petrous apex lesions.     

Reporting an alliance using an integrative approach to the management of lymphedema in India

In India 553 million persons are estimated to live in areas endemic for LF; approximately 21 million have symptomatic filariasis. Of the approximately 16.02 million cases of lymphedema caused by LF globally, 7.44 million (46.4%) are in India. India had seen diethyl carbamizine, and/or albendazole, delivered to whole populations, beginning the project to eliminate the disease. But new populations have developed the infection. In 2003 the need in resource-poor countries for morbidity control of lymphatic filariasis (LF) became clear, prompting the study by the Institute of Applied Dermatology in Kerala, India. Under this study,self help and family members assisted in home-based care, combining compression bandaging, yoga exercises, heat therapy using steaming, and skin care according to Ayurvedic medicine. Lymphedema presents with different patterns in the skin with gross changes in the epidermis, dermis, or subcutaneous tissue. Skilled and time-consuming counselling is important to give patients support. An almost immediate reduction in inflammatory episodes from 80.4% to 8.6% shows up within 2 or 3 weeks, and therefore, intake of antibiotics can be stopped. The second major response is reduction in the size of the limb. Volume reduction for large-sized limbs at 3 months is 39%, with a confidence interval of 4.9 to 5.9 L.     

The use of a quadruped as an in vivo model for the study of the spine – biomechanical considerations

Animal models in spine research are often criticized for being irrelevant to the human situation due to the horizontal position of the spine. Whether this is justified from a biomechanical point of view can be questioned. The purpose of the study reported here was to provide arguments that a quadruped can be a valuable in vivo model for the study of the spine in spite of its horizontal position. Relevant literature is reviewed, and biomechanical analyses were made of the standing and walking quadruped. Further, the vertebral trabecular bone architecture was quantitatively analysed by computer and interpreted in the light of Wolff's law. Due to the fact that spinal segments cannot withstand substantial bending moments, additional tensile forces from muscles and ligaments are necessary to control the posture of a quadruped spine. As a consequence, the spine is mainly loaded by axial compression. The trabeculae in a goat's vertebral body were found to course horizontally between its anterior and posterior endplates, implying that the main load within the vertebral body was indeed an axial compression force. The density of the vertebrae of quadrupeds is higher than that of human vertebrae, suggesting that the quadruped has to sustain higher axial compression stresses. The quadruped spine is mainly loaded along its long axis, just like the human spine. The quadruped can thus be a valuable animal model for spine research. An important point of difference is the higher axial compression stress in quadrupeds, which leads to higher bone densities in the vertebrae. This puts some limitations on the transferability of the results of animal experiments to the human situation.     

Laparoscopy as an aid in diagnosis and management of the impalpable testis

Fourteen children with impalpable testes, 10 bilateral and 4 unilateral, were examined laparoscopically. Eleven testes and two primitive undifferentiated gonads were seen in the abdomen. Exploration of the inguinal canals into which the vasa and testicular vessels were seen passing from the abdomen revealed a further two testes but nine were absent. One testis had atrophied as a result of previous torsion. Inappropriate internal genitalia were seen in two boys with hypospadias. One boy in whom both testes were seen in the abdomen had undergone a previous unsuccessful surgical exploration. None of the children developed any complications from the laparoscopy and the examination failed to reveal only one abdominal testis.     

The use of an in vivo model to study the effects of hyperhomocysteinaemia on vascular function

BACKGROUND/AIMS: To use an in vivo rat model of hyperhomocysteinaemia (HHCy) to study its impact on vascular function. METHODS: Twenty rats were fed either a control or HHCy-inducing diet for 10 wk. The response of aortic rings to contraction with phenylephrine, and relaxation to acetylcholine (endothelium-dependant relaxation) or sodium nitroprusside (endothelium-independent relaxation) was analyzed. The results were compared using an analysis of variance (ANOVA). RESULTS: There was a significant elevation of HCy in the treated group (20.5 versus 1.6 micromol/L, P = 0.004). There was no significant difference between the two groups in blood pressure measurements (ANOVA, P = 0.152). In a dose-dependant manner, phenylephrine elicited significantly greater contraction in aorta taken from HHCy rats than that taken from controls (ANOVA, P < 0.001), acetylcholine elicited significantly less percentage relaxation in aorta taken from HHCy rats than from controls (ANOVA, P = 0.003) and though sodium nitroprusside stimulated less percentage relaxation in aorta taken from HHCy rats than controls, this did not reach significance (ANOVA, P = 0.051). CONCLUSIONS: In diet induced hyperhomocysteinaemic rats, there is enhanced vascular contraction in response to phenylephrine and impaired endothelium-dependant relaxation in response to acetylcholine.     

Chemotherapy of carcinoma of the prostate and testis: experimental study in vivo and in vitro

Prostate cancer: Considering the stagnation in chemotherapy of prostate cancer in recent years, the following experiments were carried out to determine their clinical value. Surgical specimens from 6 patients, 2 permanent cell lines (EB 33 and PC 93) originated from human prostate cancer and a tumor line serially transplanted in nude mice (PC-NCC) were subjected to chemosensitivity tests such as human tumor cloning assay (HTCA) and/or in vivo tumor growth curve experiments using nude mice. The possible chemosensitive drugs screened by using surgical specimens and PC-NCC tumor were cisplatinum (CDDP), bleomycin (BLM), 5-FU, vincristine (VCR), adriamycin (ADM) and methotrexate (MTX). Most of these drugs were also judged as "effective" by HTCA using a permanent cell line. The minimal discrepancy among them may lead to the conclusion that an in vitro assay using a cell line can substitute for the assay using surgical specimens which can not be obtained frequently. Partly based on the data obtained a chemotherapy regimen, VPM-CisCF, consisting of VCR, peplomycin, MTX, CDDP, cytosine arabinoside (Ara-C) and 5-FU, was designed. The effectiveness of this regimen was demonstrated experimentally. Testis cancer: Two different lines of experiments were performed. A human testicular cancer serially transplanted in nude mice was repeatedly exposed to CDDP in vivo to obtain hyposensitivity to this drug. The synergistic effect of CDDP and VP-16 was demonstrated in the tumor thus obtained. One of its mechanisms has been suggested by partial accumulation of cancer cells in the G1-S and G2-M phase in which CDDP exerts its potential effect.(ABSTRACT TRUNCATED AT 250 WORDS)     

Complete removal of an intraspinal and extraspinal cervical chordoma in one stage using the lateral approach. Technical note

The authors describe a precise surgical technique in which a large intraspinal and extraspinal, multivertebral, cervical chordoma was completely removed in one stage using the lateral approach. The patient in this case was a 29-year-old woman who presented with signs of radicular pain in the left C-3 area. Computed tomography and magnetic resonance imaging demonstrated a large intra- and extraspinal multivertebral tumor from C-2 to C-5, a finding that suggested a cervical chordoma. The tumor was completely removed in one stage using the lateral approach while controlling the vertebral artery (VA), and a partial corporectomy of C2-5 was also performed. Results from a postoperative histopathological examination confirmed that the tumor was a typical chordoma. The patient's postoperative course was uneventful. Cervical chordomas are typically excised using a posterior-anterior surgical approach with partial resection of the tumor. The lateral approach was appropriate in this patient for complete resection in one stage, because it enabled the surgeons to control the VA and access both extraspinal and intraspinal components of the chordoma.