Unilateral or bilateral vagotomy induces ovulation in both ovaries of rats with polycystic ovarian syndrome

BACKGROUND

Injecting estradiol valerate (EV) to pre-pubertal or adult female rat results in effects similar to those observed in women with polycystic ovarian syndrome (PCOS). One of the mechanisms involved in PCOS development is the hyperactivity of the sympathetic nervous system. In EV-induced PCOS rats, the unilateral sectioning of the superior ovarian nerve (SON) restores ovulation of the innervated ovary. This suggests that, in addition to the sympathetic innervation, other neural mechanisms are involved in the development/maintenance of PCOS. The aims of present study were analyze if the vagus nerve is one of the neural pathways participating in PCOS development.

METHODS

Ten-day old rats were injected with EV dissolved in corn oil. At 24-days of age sham-surgery, unilateral, or bilateral sectioning of the vagus nerve (vagotomy) was performed on these rats. The animals were sacrificed at 90-92 days of age, when they presented vaginal estrous preceded by a pro-estrus smear.

RESULTS

In EV-induced PCOS rats, unilateral or bilateral vagotomy restored ovulation in both ovaries. Follicle-stimulating hormone (FSH) levels in PCOS rats with unilateral or bilateral vagotomy were lower than in control rats.

CONCLUSIONS

This result suggests that in EV-induced PCOS rats the vagus nerve is a neural pathway participating in maintaining PCOS. The vagus nerve innervates the ovaries directly and indirectly through its synapsis in the celiac-superior-mesenteric ganglion, where the somas of neurons originating in the SON are located. Then, it is possible that vagotomy effects in EV-induced PCOS rats may be explained as a lack of communication between the central nervous system and the ovaries.

Unilateral sectioning of the superior ovarian nerve of rats with polycystic ovarian syndrome restores ovulation in the innervated ovary

The present study tested the hypothesis that if polycystic ovary syndrome (PCOS) results from activating the noradrenergic outflow to the ovary, unilaterally sectioning the superior ovarian nerve (SON) will result in ovulation by the denervated ovary, and the restoration of progesterone (P4), testosterone (T) and estradiol (E2) normal serum level. A single 2 mg dose of estradiol valerate (EV) to adult rats results in the development of a syndrome similar to the human PCOS. Ten-day old rats were injected with EV or vehicle solution (Vh) and were submitted to sham surgery, unilateral or bilateral sectioning of the SON at 24-days of age. The animals were sacrificed at 90 to 92 days of age, when they presented vaginal estrus preceded by a pro-estrus smear. In EV-treated animals, unilateral sectioning of the SON restored ovulation by the innervated ovary and unilateral or bilateral sectioning of the SON normalized testosterone and estradiol levels. These results suggest that aside from an increase in ovarian noradrenergic tone in the ovaries, in the pathogenesis of the PCOS participate other neural influences arriving to the ovaries via the SON, regulating spontaneous ovulation. Changes in P4, T and E2 serum levels induced by EV treatment seem to be controlled by neural signals arising from the abdominal wall and other signals arriving to the ovaries through the SON, and presents asymmetry.

[The pyramidal tract: new pathways]

OBJECTIVE

To review some anatomofunctional aspects of the pyramidal tract which are relevant in clinical practice, especially the newer concepts.

DEVELOPMENT

a) Although the motor function is best known, the pyramidal tract also has sensory functions, modulating the transmission of impulses in the spinal cord. In fact, motor function is a recent acquisition on the evolutionary scale. b) Other descending pathways, such as the cortico reticulospinal path, participate in voluntary movements. However, the pyramidal pathway is necessary for fine movements of the hand. c) Most of the pyramidal fibres control movements of the contralateral side of the body, but there are a few fibres which do not cross to the other side and play a part in ipsilateral body movements. These fibres seem to contribute to motor recovery following a brain lesion. d) Classically it is recognized that the motor cortex and pyramidal fibres follow a somatotopical distribution. Nevertheless territories corresponding to different parts of the body are superimposed to a considerable extent and may be modified on very diverse occasions. e) Experimentally it has been proved that a circumscribed lesion of the pyramidal pathway does not cause hyper reflexia or spasticity. The hyper reflexia and spasticity habitually seen in patients with pyramidal syndrome is due to lesions of other descending pathways.

CONCLUSION

The pyramidal tract is anatomically and functionally related to other nerve structures and its activity is therefore integrated within the nervous system.

[A radiological study of the cervical alterations in Down syndrome. New findings on computerized tomography and three dimensional reconstructions]

OBJECTIVE

We studied a large proportion of the population in our health district who have Down's syndrome to determine the incidence and variety of changes in the spine and to define the guidelines for preventive diagnosis advisable in relation to atlanto-axial instability, a common disorder in these patients.

PATIENTS AND METHODS

First phase: a plain X-ray of the cervical spine in a neutral lateral projection and in flexion in 188 patients, measuring the atlanto-odontoid distance. Second phase: computerized tomography (CT) studies and three dimensional reconstructions in 25 patients (13.3%) chosen at random. The axial cuts from the upper portion of C3 to the occiput were 3 mm in thickness with 3 mm intervals and a standard reconstruction algorithm.

RESULTS

The incidences of atlanto-axial instability with an atlodontoid distance (3)5 mm were not comparable with the published series. There was a lower incidence (4.2%), with no difference between measurements in flexion and in the neutral lateral views. There was a greater incidence of malformations than in other reports, including a rare case of os odontoideum and also constant asymmetry of the occipital condyles (100%) in the patients of the CT series and consequently instability of the atlas (96%) and off-centered odontoides (84%).

CONCLUSIONS

The study showed that there was deficient asymmetrical development of the occipital bone, which caused different heights of the occipital condyles and led to cervico-cranial mal-position. For study of the degree of error of position and congenital anomalies. We recommend replacing plain X-ray studies by CT with three dimensional reconstructions.

The glenolabral articular disruption lesion: MR arthrography with arthroscopic correlation

OBJECTIVE

The purpose of this study was to describe the MR arthrography appearance of the glenolabral articular disruption (GLAD) lesion. Proper diagnosis of this lesion is important because it can be a source of persistent shoulder pain that requires surgical repair and because it is often difficult to diagnose clinically.

MATERIALS AND METHODS

Findings on MR arthrography were retrospectively correlated with the clinical histories and physical examination findings of six patients in whom we saw the typical appearance of the GLAD lesion. Four of these patients underwent follow-up arthroscopy that included surgical proof of GLAD lesions.

RESULTS

Five of the six patients had a documented glenohumeral impaction injury associated with an abducted externally rotated shoulder. All six patients had persistent shoulder pain, but their shoulders were stable during routine examination. In all patients, MR arthrography showed a superficial tear of the anteroinferior labrum with an adjacent articular cartilage injury. The torn labrum remained firmly attached to the anterior scapular periosteum, and contrast material was seen to extend into the labral tear and cartilaginous defect.

CONCLUSION

The MR arthrography findings of GLAD lesions include a nondisplaced tear of the anteroinferior labrum with an adjacent chondral injury. The pattern of chondral injury can range from a cartilaginous flap tear to a depressed osteochondral injury of the articular cartilage and underlying bone.

Rheumatoid nodule of the foot: MRI appearances mimicking an indeterminate soft tissue mass

Subcutaneous rheumatoid nodules occur commonly in advanced cases of rheumatoid arthritis, but only rarely appear in the feet. We present a case of a subcutaneous rheumatoid nodule arising in the heel pad of a 68-year-old man with a long history of rheumatoid arthritis, along with a review of the literature. The appearance of the mass on MRI is illustrated and correlated with the histologic findings. The MRI appearance of a subcutaneous rheumatoid nodule is that of a nonspecific ill-defined mass with long T1- and long T2-relaxation times. A differential diagnosis for similar appearing masses is offered.

Recent advances in magnetic resonance imaging of the musculoskeletal system

Numerous recent technical innovations in magnetic resonance imaging have dramatically improved the imaging evaluation of musculoskeletal disease; however, with the introduction of new techniques comes the risk of inappropriate applications and unanticipated pitfalls in interpretation. Some of the practical and theoretical implications of these recent innovations as well as potential caveats associated with their use are highlighted in the following discussion.

[Deferred repair of surgical ureteral lesions]

Our experience in surgical injuries of the ureter, as well as the therapeutic approach followed to repair them as expounded in this paper. Immediate nephrostomy following diagnosis, and restoration deferred a minimum of three weeks have provided good results, as well as it has allowed us to detect and achieve spontaneous restoration in one case. These reasons, together with the absence of technical difficulties during the second intervention, invite us to consider the reevaluation and deferred restoration--if appropriate--of the surgical ureteral injuries as a therapeutic approach from which a number of patients can profit.

[Pubo-vaginal percutaneous suspension by the Gittes technique for stress incontinence. Initial experience]

The paper presents our initial experience with endoscopic suspension of the vesical neck, as per the modification introduced by Gittes and based on incorporation through the vaginal mucosa of non-absorbable single-filament sutures. In this way it is feasible to use a simple non-incisive vaginal surgery with minimum morbidity. Good results have been obtained so far in six of the seven patients operated on. No complications have presented following tube retrieval on the second day. It is our belief that these initial results can be a reasonable basis to a wider use of this technique and to know its long-term results in treating stress incontinency through urethral hypermobility.

[Incidental carcinoma of the kidney with renal vein thrombosis]

Incidental carcinoma of kidney is an increasingly common pathology as a result of a wider use of high resolution diagnostic methods. The special characteristics of these tumors, usually small and in a low grade or stage, make conservative surgery to be considered as a valid therapeutical option. An incidental carcinoma of kidney with tumoral thrombosis of the renal vein undetected in the pre-surgical study, circumstance which allows to emphasize the malignant potential of these tumors is presented here. Based on this, we believe that a meticulous evaluation of the renal vein condition should be made, in patients considered as possible candidates for conservative surgery. In this sense, selective renal phebography and magnetic resonance could be considered explorative means that play an important role in the introduction of renal preservation surgery, if future studies show that its use allows an early detection of the tumoral condition of renal vein.