Age-related changes in the diurnal rhythm of serotonin turnover in microdissected brain areas of estradiol-treated ovariectomized rats

The purpose of this study was to determine whether 1) a diurnal rhythm in serotonin turnover is present in specific hypothalamic nuclei of middle-aged ovariectomized rats and 2) in middle-aged animals exposure to estrogen can induce the pattern of serotonin dynamics which appears necessary for the occurrence of an LH surge in young rats. Young (3-4 month old) and middle-aged (8-10 month old) rats which demonstrated estrous cyclicity were bilaterally ovariectomized. Seven days later half of the young and middle-aged animals received Silastic estradiol capsules. On day 9 post ovariectomy the groups were again divided; half of the rats in each group were killed at 0800, 1200, 1800, and 2400 h. Remaining animals were treated with pargyline (75 mg/kg BW, ip) at these times and were killed 10 min later, and the following brain areas were microdissected and analyzed for serotonin (5HT) and 5-hydroxyindole acetic acid: median eminence (ME), suprachiasmatic nucleus (SCN), medial preoptic nucleus (MPN), arcuate nucleus (AN), and globus pallidus. In young ovariectomized rats the SCN, MPN, and AN exhibited a diurnal rhythm in 5HT activity which was high during the light hours and low during the dark. The diurnal rhythm could not be detected in any hypothalamic nuclei of ovariectomized middle-aged animals. The loss in the circadian component of 5HT activity is not due to a loss in serotonergic function, since overall turnover rates were not reduced compared to young animals. Estrogen treatment modified the diurnal pattern of 5HT activity in the SCN, MPN, and AN in young rats but had no effect in the middle-aged rats. In young rats, estrogen induced a transitory rise in ME-5HT turnover at 1200 h, just before the expected onset of the LH surge. In middle-aged animals the increase in ME-5HT turnover did not occur until 1800 h and correlates with a delay in the initiation of the estradiol-induced LH surge. We conclude that: 1) there is a loss in the rhythm of 5HT activity in middle-aged rats and 2) the diurnal rhythmicity of 5HT turnover may be necessary for the maintenance of normal cyclic release of LH.     

Composite resection of posterior pelvic malignancy.

Advanced pelvic cancer is a formidable challenge to surgical resection. These tumors commonly invade the bony pelvis, may involve other viscera, and usually have been irradiated previously. The authors are presenting experience with 76 patients who had composite resection of posterior or lateral pelvic malignancy. Fifty-eight patients had secondary cancers involving the musculoskeletal pelvis. This included 47 patients with advanced carcinoma of the rectum (41 curative, 6 palliative), 10 epidermoid cancers of the anorectum (8) or cervix (2), and 1 bladder cancer. Among the 18 patients with primary pelvic tumors were three patients with chordomas, six with bone tumors (osteosarcoma chondrosarcoma, grade III giant cell tumor), and nine with soft tissue tumors. All required major resection of the sacrum or pelvic side walls, and one half had an additional exenterative procedure. The overall mortality rate was 7.9%. Long-term estimated survival was 24% in patients having curative resection of recurrent rectal cancer, and 22.5% in 10 patients with advanced epidermoid cancer. Fifty per cent of patients with primary bone or soft tissue tumors survived from 13 to 88 months. Most patients had reasonable return of function, and were able to return to work or resume their normal previous lifestyle.     

Spinal MR findings in neurofibromatosis types 1 and 2.

PURPOSE: To evaluate the frequency and nature of spinal pathology, the frequency of clinically silent lesions, and the potential benefit of screening spinal MR in neurofibromatosis patients. PATIENTS AND METHODS: 28 neurofibromatosis type-1 (NF-1) patients and nine neurofibromatosis type-2 (NF-2) patients were studied with postcontrast spinal MR imaging. RESULTS: NF-1: One patient had a biopsy-proven low-grade glioma; five patients, intradural, extramedullary masses (N = 23); one patient, extradural masses (N = 2) (neurofibromas); 16 patients had bony abnormalities; and three patients thecal sac abnormalities. NF-2: Five patients demonstrated intramedullary masses (five/eight ependymomas); nine patients, intradural, extramedullary masses (meningiomas, schwannomas); and four patients, bony abnormalities. Eight/10 NF-1 and four/nine NF-2 patients had asymptomatic masses. CONCLUSION: Intradural disease is common, often asymptomatic, and often presents at a young age in NF-1 and NF-2 patients. Because of the propensity to develop significant asymptomatic as well as symptomatic intradural disease, screening of the entire spine with MR is recommended in both NF-1 and NF-2 patients.     

Brain parenchyma motion: measurement with cine echo-planar MR imaging.

With echo-planar magnetic resonance (MR) imaging, the authors measured the intrinsic pulsatile motion of brain parenchyma. Phase-sensitive, electrocardiography-gated, two-dimensional cine images were acquired throughout the cardiac cycle by using a spin-echo, blipped echo-planar MR pulse sequence. Transverse and coronal planes were obtained in 14 healthy volunteers. Corrections were made for gross head motion. Brain motion consisted of a rapid displacement in systole, with a slow diastolic recovery. The motion occurred chiefly in the cephalocaudal and lateral directions; the anteroposterior motions were relatively small. Cephalocaudal velocities increase with proximity to the foramen magnum. The lateral motion is mainly a compressive motion of the thalami. Brain parenchymal velocities were as high as 2 mm/sec caudally in the brain stem and 1.5 mm/sec medially in the thalami. Net parenchymal excursions were at most 0.5 mm. Phase-based echo-planar velocity measurements agreed well with echo-planar Fourier velocity zeugmatography measurements and were consistent with reported values. Velocity mapping with echo-planar imaging offers a rapid and flexible method of assessing the pulsation velocities of the human brain.     

Stage I-II low grade non-Hodgkin's lymphoma: prognostic factors and treatment results.

48 patients with stage I-II low-grade non-Hodgkin's lymphoma were treated by radiation and/or chemotherapy between 1970 and 1986. The histologic types were diffuse lymphocytic well differentiated, eleven patients; nodular lymphocytic poorly differentiated, 28 patients; nodular mixed, nine patients. Complete remission was obtained in 45 patients (94%). Overall survival was 83% and 68% at five and ten years, respectively. Five and ten-year relapse-free survival of complete responders was 71% and 57%, respectively. Univariate analysis of potential prognosticators showed the following to significantly increase the survival rate: one or two sites of disease (p less than 0.01), stage I (p less than 0.02), age less than 65 years (p less than 0.02), complete excision of tumor mass (p less than 0.03), and the use of radiotherapy (p less than 0.02). The extent of radiotherapy field did not affect survival. Multivariate analysis by the stepwise proportional hazards model of Cox showed that the use of radiotherapy was the factor which significantly produced better survival figures (p less than 0.03). It is concluded that two thirds of stage I-II low-grade lymphoma patients are potentially curable; radiotherapy plays a major role in the management.     

Diagnostic sonography of the fetal genitourinary tract

Fetal diagnosis has vastly improved over the last decade. Ultrasound has become the imaging modality of choice. As real-time equipment has improved technologically, the ability to deduce subtle abnormalities has greatly increased. The fetal genitourinary tract may be evaluated for renal dysplasias, anomalies, or obstruction. Points of obstruction and, at times, the exact cause of obstruction may be deduced. Abnormalities of the ureter, bladder, urethra, scrotum, or reproductive system can be detected.     

T cells in the spinal cord in experimental autoimmune encephalomyelitis are matrix adherent and secrete tumor necrosis factor alpha.

We examined T cells isolated from an autoimmune tissue lesion and from lymphoid organs for their ability to secrete tumor necrosis factor-alpha (TNF-alpha) and to adhere to extracellular matrix (ECM) proteins. CD4+ T cells were obtained from spleens, popliteal lymph nodes, and spinal cords of Lewis rats that had been immunized with myelin basic protein (MBP) to induce experimental autoimmune encephalomyelitis (EAE). We now report that, irrespective of whether or not the T cells were activated with MBP or the T cell mitogen concanavalin A (ConA), the T cells isolated from the spinal cord lesions secreted greater amounts of TNF-alpha and adhered better to ECM than did T cells from the draining lymph node. Thus, the lesions of EAE concentrate a subpopulation of CD4+ T cells with enhanced ability to interact with blood vessel wall components and to secrete TNF-alpha.