Estrogen and progesterone receptor expression in uterine and extrauterine leiomyosarcomas: an immunohistochemical study.

The authors have noted anecdotal cases of extrauterine leiomyosarcomas (LMS) with estrogen receptor (ER) and progester-one receptor (PR) immunoreactivity. However, there are few studies that have compared ER and PR immunoexpression in LMS of uterine and extrauterine origin. The authors obtained a representative formalin-fixed, paraffin-embedded tissue block from cases of uterine LMS (n = 15) and extrauterine LMS (n = 16) from the archives of the Cleveland Clinic Foundation and performed immunohistochemical staining for ER and PR. Staining was evaluated by 2 observers in a semiquantitative manner using the following scale: 0, no nuclear staining; 1+, 1 to 25% of nuclei stained; 2+, 26 to 50% of nuclei stained; 3+, 51 to 75% of nuclei stained; 4+, 76 to 100% of nuclei stained. The majority of uterine LMS stained for ER (13 of 15, 87%), PR (12 of 15, 80%), or both ER and PR (12 of 15, 80%), with most cases showing 3+ or 4+ positive staining. For the extrauterine LMS cases, staining for ER was seen in 4 of 16 cases (25%), staining for PR was observed in 2 of 16 cases (13%), and staining for both ER and PR was seen in 2 of 16 cases (13%). One extrauterine LMS showed 4+ coexpression of ER and PR, but the remaining extrauterine cases showed only 1+ ER and/or PR immunoreactivity. These data suggest that most uterine LMS coexpress ER and PR, and most extrauterine LMS do not stain for these antigens. However, a subset of extrauterine LMS are ER and/or PR immunoreactive. This raises the possibility that hormonal manipulation may be beneficial in the treatment of these therapeutically recalcitrant tumors.     

Activation of the Akt/GSK3beta signaling pathway mediates survival of vulnerable hippocampal neurons after transient global cerebral ischemia in rats.

Recent studies have revealed that the phosphatidylinositol 3-kinase (PI3-K) pathway is involved in apoptotic cell death after experimental cerebral ischemia. The serine-threonine kinase, Akt, functions in the PI3-K pathway and prevents apoptosis by phosphorylation at Ser473 after a variety of cell death stimuli. After phosphorylation, activated Akt inactivates other apoptogenic factors, including glycogen synthase kinase-3beta (GSK3beta), thereby inhibiting cell death. However, the role of Akt/GSK3beta signaling in the delayed death of hippocampal neurons in the CA1 subregion after transient global cerebral ischemia (tGCI) has not been clarified. Transient global cerebral ischemia for 5 mins was induced by bilateral common carotid artery occlusion combined with hypotension. Western blot analysis showed a significant increase in phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) in the hippocampal CA1 subregion after tGCI. Immunohistochemistry showed that expression of phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) was markedly increased in the vulnerable CA1 subregion, but not in the ischemic-tolerant CA3 subregion. Double staining with phospho-GSK3beta (Ser9) and terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling showed different cellular distributions in the CA1 subregion 3 days after tGCI. Phosphorylation of Akt and GSK3beta was prevented by LY294002, a PI3-K inhibitor, which facilitated subsequent DNA fragmentation 3 days after tGCI. Moreover, transgenic rats that overexpress copper/zinc-superoxide dismutase, which is known to be neuroprotective against delayed hippocampal CA1 injury after tGCI, had enhanced and persistent phosphorylation of both Akt and GSK3beta after tGCI. These findings suggest that activation of the Akt/GSK3beta signaling pathway may mediate survival of vulnerable hippocampal CA1 neurons after tGCI.     

Autologous blood transfusion for pediatric bone marrow donors.

Nine normal bone marrow donors aged 7-166 months (median 69 months) received autologous red cells which had been removed from their marrow harvest after collection. The median volume of marrow removed from the donors was 18.6 ml/kg which was equivalent to a median blood volume loss of 23.3%. Three infant donors were transfused with autologous red blood cells intraoperatively. These cells had been salvaged from the initial marrow aliquot and were transfused while bone marrow harvesting continued. No donors required homologous blood transfusion. This technique is useful for marrow donors in the pediatric age group when preharvest autologous blood collection is not feasible or available.     

Prognostic factors in diffuse proliferative lupus glomerulonephritis

A number of clinical laboratory and biopsy-derived parameters were assessed for their prognostic significance in the short (24 months), intermediate (60 months) and long terms in 45 patients (43 female, 2 male) with diffuse proliferative lupus glomerulonephritis (DPGN). The factors evaluated were serum creatinine (SCr) and urinary protein at time of biopsy, initial dose of prednisone and immunosuppressive after biopsy, activity index (AI), chronicity index (CI), their individual components, extent of extraglomerular (tubulo-interstitial) immune deposits (EGD) and mean number of intraglomerular monocytes per glomerulus (NSE index). Using proportional hazards analysis to evaluate the parameters, SCr (P = 0.003), AI (P = 0.005) and NSE index (P = 0.038) were shown to be significant predictors of outcome when all variables except the components of AI and CI were considered. When AI and CI were omitted but their components included, SCr (P = 0.0005), NSE index (P = 0.024), extent of karyorrhexis (P = 0.035) and glomerulosclerosis (P = 0.033) were then demonstrated to be significant prognostic factors of DPGN. The results suggest that intraglomerular monocyte infiltration has a protective effect and confirm that AI index is a relatively powerful predictor of outcome. Histologic and nonhistologic biopsy factors contribute significant additional prognostic information to that provided by SCr.     

Cationic lipids enhance cellular uptake and activity of phosphorothioate antisense oligonucleotides.

We have investigated the use of a cationic lipid preparation to enhance antisense oligonucleotide activity in human umbilical vein endothelial cells. A liposomal preparation containing the cationic lipid N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA) was found to increase by at least 1000-fold the potency of an antisense oligonucleotide (ISIS 1570) that hybridizes to the AUG translation initiation codon of human intercellular adhesion molecule-1. In the presence of 8 microM DOTMA, 6-15-fold more 35S-ISIS 1570 associated with cells, at oligonucleotide concentrations from 0.01 to 5 microM, than did in the absence of DOTMA. Both 35S-ISIS 1570 association with cells and antisense activity were increased as a function of DOTMA concentration and with increasing time of incubation with the cationic lipid. Fluorescein-labeled ISIS 1570 was used to assess the intracellular distribution of the oligonucleotide in the presence and absence of DOTMA. In the absence of DOTMA, the oligonucleotide localized to discrete structures in the cytoplasm of the cell, resulting in a punctate fluorescence pattern. In the presence of DOTMA, cellular fluorescence markedly increased and the oligonucleotide localized within the nucleus, as well as to discrete structures in the cytoplasm. Accumulation of the oligonucleotide in the nucleus in the presence of DOTMA was time and temperature dependent. Nuclear accumulation was inhibited by preincubation of the cells with monensin but not chloroquine, NH4Cl, nocodazole, colcemid, or brefeldin A. These data demonstrate that cationic lipids increase antisense activity by increasing the amount of oligonucleotide associated with cells and altering intracellular distribution of the oligonucleotide.     

How accurate was GMENAC?--A retrospective review of supply projections for diagnostic radiologists.

In 1982, the Graduate Medical Education National Advisory Committee (GMENAC), a prominent national panel, predicted there would be 25,650 full-time equivalent (FTE) diagnostic radiologists, a 34% oversupply, by 1990. The radiologists involved in GMENAC, however, using models developed by the American College of Radiology, projected 19,800 FTE diagnostic radiologists in 1990, which was similar to the GMENAC estimate of need. The disagreement arose principally from different assumptions about residents entering the specialty. Recent data show there actually were approximately 21,900 FTE diagnostic radiologists in 1990. The radiologists' projection was 10% below this figure; the GMENAC projection was 17% above it. GMENAC erred principally in assuming diagnostic radiology residencies would not replace general radiology residencies, but rather be an addition to them. The radiologists erred principally in their assumption about the effects of the financial problems of hospitals on the number of residency positions. Accurate long-term projection of physician supply in individual specialties may well not be feasible.     

α-Bungarotoxin blocks the nicotinic receptor mediated increase in cell number in a neuroendocrine cell line

Exposure of H69 small cell lung carcinoma cells to nicotinic agonists resulted in a significant increase (up to 100%) in cell number after 6 to 12 days. The effect of nicotine (10⁻⁸ M to 10⁻⁴ M) was both dose and time dependent as was that of another nicotinic agonist cytisine (10⁻⁶ M to 10⁻⁴ M). Interstingly, both the nicotine and cytisine induced increases in H69 cell number were blocked by α-bungarotoxin, as well as d-tubocurarine a nicotinic blocker which appears to interact with most nicotinic receptors. These results suggest that the nicotine induced increase in cell number is mediated through an interaction at the nicotinic α-bungarotoxin receptor. This idea is further supported by experiments which show (1) that H69 cells possess high affinity α-bungarotoxin sites (K_d = 25 nM, B_max = 10.4 fmol/10⁶ cells) with the characteristics of a nicotinic α-bungarotoxin receptor and (2) that the potencies of nicotinic receptor ligands in the α-bungarotoxin binding assay were similar to those observed in the functional studies. Northern analysis showed that mRNA for α7, a putative nicotinic α-bungarotoxin binding subunit, and for α5 were present in H69 cells. The present data provide further evidence that nicotine increases cell number in small cell lung carcinoma and are the first to show that this effect is mediated through an interaction at the nicotinic α-bungarotoxin receptor population. These results suggest that the α-bungarotoxin site may be involved in modulating proliferative responses in neuroendocrine derived SCLC cells.     

Plasma Histamine After Methacholine, Allergen, and Aspirin Challenges

Plasma histamine levels were measured by radio-enzymatic technique in seven patients following 10 challenges: five methacholine challenge tests, four antigen inhalation challenge tests, and one oral aspirin challenge test. Baseline plasma histamine was the same in all patients except in the aspirin-challenged patient, who had a higher baseline histamine level. There was no statistical change in the level of histamine throughout the test in either the methacholine-challenged or the antigen-challenged patients, whereas there was a marked increase in histamine levels in the aspirin challenged patient. A possible explanation is that methacholine and antigen are inhaled and therefore have primarily local effects on the lung, whereas oral aspirin has a systemic effect with consequently systemic changes in histamine which are detectable as changes in plasma level.