The Robert Wood Johnson Foundation

Eleven patients with active unicameral bone cysts were treated primarily with placement of demineralized bone matrix in the cyst by using a two-needle technique and a custom large-bore needle. Cyst healing was rated according to the Neer classification, and the average time of healing was 4.5 months. The demineralized bone matrix demonstrated an ability to obliterate the cyst in nine of 11 patients by using a single injection within 4-5 months, and at 2 years' follow-up, no cysts were deemed active or recurrent.     

Stromal progesterone receptors mediate the inhibitory effects of progesterone on estrogen-induced uterine epithelial cell deoxyribonucleic acid synthesis

The role of epithelial and stromal progesterone (P) receptors (PR) in the regulation of uterine epithelial DNA synthesis by P was investigated by analyzing the four types of tissue recombinants prepared with uterine stroma (S) and epithelium (E) from wild-type (wt) and PR knockout (PRKO) mice: wt-S + wt-E, PRKO-S + PRKO-E, wt-S + PRKO-E, and PRKO-S + wt-E. 17-Beta estradiol (E2) stimulated DNA synthesis in all four types of tissue recombinants. On the other hand, P inhibited E2-induced DNA synthesis only in tissue recombinants prepared with wild-type (PR-positive) stroma (wt-S + wt-E or wt-S + PRKO-E) but not knockout (PR-negative) stroma (PRKO-S + wt-E or PRKO-S + PRKO-E). These results clearly demonstrate that the inhibitory effect of P on uterine epithelial DNA synthesis is mediated by stromal PR. Epithelial PR is neither necessary nor sufficient for P inhibition of E2-induced epithelial DNA synthesis.     

Restenosis and remodeling after percutaneous transluminal carotid angioplasty

INTRODUCTION: The characteristics of restenosis and remodeling after carotid percutaneous transluminal angioplasty (PTA) were badly known. OBJECTIVE: To describe these characteristics in our series of carotid PTA. PATIENTS AND METHODS: A total of 78 cases of PTA for symptomatic > 70% atherosclerotic stenosis of the extracranial internal carotid artery, were selected from our series of PTA if follow-up was > 12 months. All of them were followed with extracranial continuous-wave Doppler. RESULTS: Restenosis of any degree was found in 17 cases (21.79%) and always asymptomatic. A restenosis > or = 70% was found in 5 cases (6.4%). Restenosis was mainly found in cases without residual stenosis nor dissection after PTA (p = 0.002). Restenosis was found in 16 cases (94.11%) in the first 6-months, with no progression thereafter. Remodeling of residual stenosis was frequent (17 cases; 53.11%) and found mainly during the first month after PTA. Its incidence was highest in patients with dissection treated with heparin. In cases with restenosis, remodeling was infrequent, incomplete and occurred after 18-24 months. CONCLUSIONS: 1. Significant restenosis after PTA due to myointimal proliferation, was infrequent. All cases were asymptomatic, under antiplatelet treatment. A new interventional procedure might not be necessary. 2. Complete remodeling was frequently found after 1-month control, mainly in arteries with some residual stenosis and dissection after PTA.     

Hypermutability of mouse chromosome 2 during the development of x-ray-induced murine myeloid leukemia

In an effort to identify the precise role of a deletion at regions D-E of mouse chromosome 2 [del2(D-E)] during the development of radiation-induced myeloid leukemia, we conducted a serial sacrifice study in which metaphase chromosomes were examined by the G-banding technique. Such metaphase cells were collected from x-irradiated mice during the period of transformation of some of the normal hematopoietic cells to the fully developed leukemic phenotype. A group of 250 CBA/Ca male mice (10-12 weeks old) were exposed to a single dose of 2 Gy of 250-kilovolt-peak x-rays; 42 age-matched male mice served as controls. Groups of randomly selected mice were sacrificed at 20 hr, 1 week, and then at intervals of 3 months up to 24 months after x-irradiation. Slides for cytogenetic, hematological, and histological examination were prepared for each animal at each sacrifice time. An expansion of cells with lesions on one copy of chromosome 2 was evident in 20-25% of treated mice at each sacrifice time. The majority of such lesions were translocations at 2F or 2H, strongly suggesting hypermutability of these sites on mouse chromosome 2. No lesions were found in control mice. The finding leads to the possibility that genomic lesions close to 2D and 2E are aberrants associated with radiation leukemogenesis, whereas a single clone of cells with a del2(D-E) may lead directly to overt leukemia. The data also indicate that leukemic transformation arises from the cumulative effects of multiple genetic events on chromosome 2, reinforcing the thesis that multiple steps of mutation occur in the pathogenesis of cancer.     

Cytogenetic changes in 67 cranial and spinal meningiomas: relation to histopathological and clinical pattern

The cytogenetic analysis of 67 meningiomas (58 intracranial and 9 spinal tumors) identified chromosomal abnormalities in 63% of cases. When chromosomes involved in numerical and structural changes with a frequency of more than one standard deviation above the mean were considered, distinct cytogenetic patterns could be identified according to sex, anatomical location and histology. The chromosomes more frequently affected were 1, 2, 3, 4, 8, 14, 15, 19, 22, Y. No conclusion could be drawn regarding the prognostic significance of these karyotypic alterations.     

Cerebral metabolic effects of sequential periods of hypothermic circulatory arrest

During repair of congenital heart defects, extended periods of hypothermic circulatory arrest (CA) have been shown to cause short-term cerebral metabolic and flow abnormalities as well as long-term neuropsychologic dysfunction. Occasionally, a second period of CA is required during the same operative setting to revise a complicated repair. However, the metabolic effects of two consecutive periods of CA on the brain are unclear. In this study, we compared the recovery of cerebral metabolism after 60 minutes of CA with that after two sequential 30-minute periods of CA separated by a brief period of rewarming (30'SEQ). Fifteen neonatal piglets (2 to 3 kg) were placed on cardiopulmonary bypass at 100 mL.kg-1 x min-1 and cooled to 18 degrees C. Each animal then underwent either 60 minutes of uninterrupted cardiopulmonary bypass at 18 degrees C, 60 minutes of CA, or two 30-minute periods of CA separated by a brief period of rewarming. After these experimental periods, animals were rewarmed to 37 degrees C and weaned from cardiopulmonary bypass. Data were obtained before cardiopulmonary bypass and after cardiopulmonary bypass at 37 degrees C and included measurements of cerebral blood flow by xenon 133 clearance, arterial and sagittal sinus blood gases, and cerebral metabolism (mL O2.100 g-1 x min-1). Our results demonstrated that acute recovery of cerebral metabolism was significantly impaired after 60 minutes of CA and that recovery of cerebral metabolism after two sequential 30-minute periods of CA was significantly better than after 60 minutes of continuous CA.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dietary sodium restriction impairs insulin sensitivity in noninsulin-dependent diabetes mellitus

Dietary sodium restriction has a variety of effects on metabolism, including activation of the renin-angiotensin system. Angiotensin II has complex metabolic and cardiovascular effects, and these may be relevant to the effects of both nonpharmacological and pharmacological interventions in noninsulin-dependent diabetes mellitus (NIDDM). We have assessed the effect of dietary sodium restriction on insulin sensitivity and endogenous glucose production in eight normotensive patients with diet-controlled NIDDM who underwent hyperinsulinemic clamp studies in a randomized, double-blind, placebo-controlled cross-over protocol after two 4-day periods on sodium replete (160 mmol/day) and sodium deplete (40 mmol/day) diets. Mean +/- SD 24-h urinary sodium was 197 +/- 76.0 mmol (replete) and 67 +/- 19.5 mmol (deplete), P = 0.03. Insulin sensitivity was 42.0 +/- 11.3 mumol/kg.min (replete) and 37.0 +/- 11.6 mumol/kg.min (deplete), P = 0.04 (a reduction of 12%). Blood pressure was 130 +/- 21/78 +/- 11 mmHg (replete) and 128 +/- 12/73 +/- 10 mmHg (deplete). Dietary sodium restriction may result in a decrease in peripheral insulin sensitivity in normotensive patients with NIDDM, possibly via an elevation in prevailing angiotensin II concentrations.