Prevalence of clinical venous thromboembolism in the USA: current trends and future projections.

The U.S.-wide prevalence of venous thromboembolism (VTE) is unclear, with reported VTE incidence estimates varying widely. This retrospective analysis of healthcare claims data from patients in the Thomson Reuters national MarketScan(®) Commercial and Medicare databases (January 2002-December 2006) estimates the U.S. prevalence of VTE, and assesses associated temporal trends. Of 12.7 million study-eligible patients, 200,007 had VTE. The overall prevalence of VTE (cases per 100,000) increased by 33.1% during the study period: from 317 in 2002 to 422 in 2006. VTE was more prevalent in women than men throughout the study. The annual prevalence of VTE increased with age: 1,382 in patients ≥65 years versus 231 in patients <65 (2006 data). The number of U.S. adults with VTE is projected to more than double from 0.95 million in 2006 to 1.82 million in 2050. These data confirm that VTE remains a major healthcare burden in the US, particularly among the elderly, and highlight a continuing increase in prevalence of the disease. Greater efforts are required to improve awareness of VTE and improve standards of VTE prevention in healthcare organizations.

Transport of immunoglobulins from serum into colostrum.

Oligomeric, J-chain-containing immunoglobulins were observed to be transferred selectively from serum into colostrum. These studies suggest that, in the case of the mammary gland secretion, a significant role for extraglandular synthesis of IgA merits consideration. Thus, for example, colostrum may contain antibodies synthesized locally as well as antibodies synthesized in the much larger lymphoid tissues such as the gut lamina propria.

Follicle-stimulating hormone and the regulation of testosterone secretion in rabbit testes.

Regulation of testosterone secretion is presumably mediated by interstitial cell-stimulating hormone (ICSH). However, there is little information on the actions of other chemical messengers in regulating testosterone secretion. We have shown that follicle-stimulating hormone augments testosterone secretion stimuated by ICSH in rabbit testes perfused in vitro with an artificial medium.

Sequential gene regulatory events leading to glucocorticoid-evoked apoptosis of CEM human leukemic cells:interactions of MAPK, MYC and glucocorticoid pathways.

Gene expression responses to glucocorticoid (GC) in the hours preceding onset of apoptosis were compared in three clones of human acute lymphoblastic leukemia CEM cells. Between 2 and 20h, all three clones showed increasing numbers of responding genes. Each clone had many unique responses, but the two responsive clones showed a group of responding genes in common, different from the resistant clone. MYC levels and the balance of activities between the three major groups of MAPKs are known important regulators of glucocorticoid-driven apoptosis in several lymphoid cell systems. Common to the two sensitive clones were changed transcript levels from genes that decrease amounts or activity of anti-apoptotic ERK/MAPK1 and JNK2/MAPK9, or of genes that increase activity of pro-apoptotic p38/MAPK14. Down-regulation of MYC and several MYC-regulated genes relevant to MAPKs also occurred in both sensitive clones. Transcriptomine comparisons revealed probable NOTCH-GC crosstalk in these cells.

Epigenetic regulation of RNA polymerase III transcription in early breast tumorigenesis.

RNA polymerase III (Pol III) transcribes medium-sized non-coding RNAs (collectively termed Pol III genes). Emerging diverse roles of Pol III genes suggest that individual Pol III genes are exquisitely regulated by transcription and epigenetic factors. Here we report global Pol III expression/methylation profiles and molecular mechanisms of Pol III regulation that have not been as extensively studied, using nc886 as a representative Pol III gene. In a human mammary epithelial cell system that recapitulates early breast tumorigenesis, the fraction of actively transcribed Pol III genes increases reaching a plateau during immortalization. Hyper-methylation of Pol III genes inhibits Pol III binding to DNA via inducing repressed chromatin and is a determinant for the Pol III repertoire. When Pol III genes are hypo-methylated, MYC amplifies their transcription, regardless of its recognition DNA motif. Thus, Pol III expression during tumorigenesis is delineated by methylation and magnified by MYC.

Interactions of the phenylpyrazolo steroid cortivazol with glucocorticoid receptors in steroid-sensitive and -resistant human leukemic cells.

The interactions of glucocorticoids with their receptors somehow determine the cellular responses seen. The high potency glucocorticoid cortivazol differs from the usual glucocorticoids in two ways, structurally and in binding to receptors. Cortivazol contains a phenylpyrazol fused at carbon atoms 2 and 3 to the A ring of the cyclophenathrene, replacing the supposedly essential 3-keto,4,5-double bond pattern of glucocorticoids. Cortivazol binds to the glucocorticoid receptor in the cytosol from CEM C7 cells (a human acute lymphoblastic leukemia line) in a fashion consistent with interaction with at least two sites. Standard glucocorticoids show only one-site binding. In mutant leukemia cells derived from CEM C7, resistant to kill by 10(-6) M dexamethasone and deficient in standard glucocorticoid binding sites, cortivazol still finds a binding site and kills the cells. In wild-type leukemia cells, the binding sites of cortivazol, those with both higher (Kd approximately 5 x 10(-10) M) and lower (Kd approximately 1 x 10(-8] affinity appear to be on forms of the glucocorticoid receptor itself, and not on two different classes of molecules.

Resistance of human leukemic CEM-C1 cells is overcome by synergism between glucocorticoid and protein kinase A pathways: correlation with c-Myc suppression.

Glucocorticoids (GCs) induce apoptosis in lymphoid cells that contain functional GC receptors (GRs). However, GC resistance often is seen in cells with demonstrable GRs; one such line is CEM-C1. We have tested the hypothesis that positive interactions between GC and cyclic AMP (cAMP) regulate GC actions in CEM clones. Treatment of both GC-resistant CEM-C1 [resistant to 1 microM dexamethasone (Dex)] and the sensitive sister clone, CEM-C7 (approximately 65% cell death with 20 nM Dex, approximately 99% death with 1 microM Dex), with a < or = 20 microM concentration of the protein kinase A activator, forskolin, had no significant effect on cell viability. Cotreatment with Dex and forskolin resulted in a strong synergistic death response, with only approximately 10% CEM-C1 cells surviving treatment with 1 microM Dex and 20 microM forskolin. This death was blocked by the GR antagonist RU 38486. However, the extent of apoptosis did not correlate with the amount of GR protein or binding activity in either C7 or C1 cells. As reported previously, Dex-evoked cell death was associated with suppression of c-Myc in C7 cells. In CEM-C1 cells, Dex alone did not affect c-Myc; however, Dex plus forskolin suppressed c-Myc levels. To evaluate mechanisms of Dex-forskolin synergism, fresh subclones of CEM-C7 (clone 14) and CEM-C1 (clone 15) were isolated, to ensure purity of phenotype. In these, forskolin (with or without Dex) caused a similar increase in cAMP (approximately 300-fold) and phospho-cAMP-responsive element binding protein (approximately 4-5-fold) levels, whereas total cAMP-responsive element binding protein expression was not affected. GR transcription function, as tested from a GR-responsive 330-bp mouse mammary tumor virus promoter-luciferase reporter construct, was induced 8- and 4-fold by 1 microM Dex treatment of CEM-C7-14 and CEM-C1-15 cells, respectively. Forskolin (10 microM) significantly potentiated Dex response in CEM-C1-15 cells (13.5-fold) but had only a modest effect (1.5-fold) in CEM-C7-14 cells. These studies suggest that sensitization of CEM-C1 cells by cross-talk between GR and protein kinase A pathways may occur via cooperative effects on GR-mediated gene transcription.

Correlated responses in male reproductive traits in mice selected for litter size and body weight.

Correlated responses in male reproductive traits were determined at 4, 6 and 8 weeks of age in lines of mice selected for large litter size (L+), large 6-week body weight (W+), large litter size and small body weight (L+W-) and small litter size and large body weight (L-W+), and in an unselected control (K). Concentration of serum testosterone and weights of testes, seminal vesicles, epididymides and adrenal glands increased with age. Line differences in testosterone concentration were not detected. L+ and W+ males exhibited positive correlated responses in testes, epididymides and seminal vesicle weights. Testis weight adjusted for body weight was significantly larger for L+ than controls and approached significance for W+. Realized genetic correlation be-testis weight and litter size was 0.60 +/- 0.04, and the realized partial genetic correlation holding body weight constant was 0.42. Therefore, pleiotropic loci, acting via the hypothalamic-pituitary axis, affect testis weight and litter size independently of body weight. Additionally, genes influencing overall growth have a pleiotropic effect on testis weight and litter size in mice; the realized genetic correlations of body weight with testis weight and with litter size were 0.60 +/- 0.03 and 0.52 +/- 0.10. Testis weight increased in both L+W- and L-W+ males. The positive correlated response in L+W- may have resulted from changes in frequency of genes controlling reproductive processes; whereas, in L-W+ it could have been the result of changes in the frequency of genes associated with body weight.

Transfected glucocorticoid receptor and certain GR fragments evoke cell death in malignant lymphoid, not myeloid cell lines.

Previously we have shown that glucocorticoid sensitivity could be restored to a clone of glucocorticoid-resistant leukemic T cells by transfecting them with an expression vector for the glucocorticoid receptor. Furthermore, transfection with plasmids expressing fragments of the receptor containing the DNA-binding domain resulted in constitutive loss of cells. In this paper, we report the results of transfecting both types of constructs into lines of glucocorticoid-resistant human leukemic cells of T cell, B cell, and myeloid origin. In all the lymphoid lines tested, transfection of the holoreceptor gene resulted in appearance of steroid-dependent cell death. In the same lines, transfection of glucocorticoid receptor fragments expressing amino acids 1-465* (465 residues of the normal sequence plus a novel 21 amino acid C-terminus) or expressing only 398-465* caused cell death without the addition of steroids. The amount of cell loss following transfection of these constitutively lethal fragments was in the same range as that following transfection of the holo glucocorticoid receptor plus administration of glucocorticoid. However, the cell loss due to the constitutively active fragments occurred more rapidly. Neither of the myeloid lines tested were sensitive to any of the transfected constructs, with or without added steroid.

Autonomic characteristics of nonclinical panic and blood phobia.

Autonomic characteristics of nonclinical panic and blood phobia were compared using spectral analysis of the electrocardiogram (EKG), as well as more conventional cardiovascular measures. The cardiovascular responses of 11 subjects who reported recent occurrence of frequent severe panic attacks, and 10 subjects who reported intense somatic reactions to the sight of blood (including episodes of syncope) were recorded during a variety of laboratory tasks (quiet rest, reaction time/shock avoidance, face immersion, and combined reaction time/face immersion). Results suggest distinct autonomic patterns in the groups. Panickers showed (a) higher heart rate and reduced heart-rate variability (b) aberrant associations among cardiovascular measures, and (c) dominant sympathetic control of heart rate coupled with diminished vagal tone. Blood phobics generally displayed an opposite pattern. The relevance of these findings to the etiology of panic and blood phobia, as well as to biological models of anxiety disorders in general, is discussed.

Biological activities of oxysterols.

Literature dealing with the biological activities of cholesterol autoxidation products and related oxysterols in vivo and in vitro published since the previous 1981 monograph is reviewed. Although several oxysterols are important cholesterol metabolites implicated in bile acids and steroid hormones biosynthesis, effects on cellular membranes and on specific enzyme systems as well as cytotoxic, atherogenic, mutagenic, and carcinogenic activities characterize oxysterols as a class. Circumstantial evidence implicates oxysterols of the human diet and those formed in vivo with human health disorders, but recent work also supports an hypothesis that some oxysterols be endogenous intracellular regulators of de novo sterol biosynthesis. The true physiological relevance, if any, of these matters has not been adduced.

A search for mutagens in human aortal lipid extracts.

In view of hypotheses suggesting mutagenesis is implicated in atherosclerosis, a total of 18 lipid extracts of human aortal tissues was examined by the standard Ames mutagenicity bioassay using Salmonella typhimurium or by a liquid modification thereof. One lipid extract of intimal-medial tissue contained detectable mutagenic activity against test strain TA98 in the liquid medium bioassay and against TA1538 in the standard plate assay following metabolic activation. Six other samples appeared to have weak activity against strains TA98, TA1538, or TA100. The other aortal samples were nonmutagenic.

Peptide derivatives of primaquine as potential antimalarial agents.

Three peptide derivatives of primaquine were synthesized. The compounds were tested for radical curative antimalarial activity against Plasmodium cynomolgi in rhesus monkeys and blood schizonticidal antimalarial activity against Plasmodium berghei in mice. All three peptide derivatives showed activity against P. cynomolgi greater than that expected for the primaquine content of each prodrug. The toxicity of one of the peptide derivatives was less than that of primaquine in mice.

Agonists of endogenous opioid peptides suppress LH, and stimulate cortisol and growth hormone during the follicular phase in heifers.

We evaluated the effects of [D-Ala2,Me,Phe4,Met(0)ol]-enkephalin (FK 33-824) and morphine, opioid receptor agonists, on concentrations of LH, cortisol and GH during the follicular phase in heifers. During three trials, oestrous cycles of Angus heifers were synchronized by two injections of prostaglandin F2 alpha (PGF2 alpha) resulting in 17 induced follicular phases over an 80-day period. Treatments were administered 24 h after the second injection of PGF2 alpha. Blood samples were collected at 15-min intervals from 3 h before until 5 h after i.v. administration of 2 ml physiological saline (trials 1, 2 and 3), 0.5 mg morphine/kg (trials 1 and 2) or 1.8 micrograms FK 33-824/kg (trials 1 and 2) or 6.7 micrograms FK 33-824/kg (trial 3). Administration of both doses of FK 33-824 and morphine inhibited episodic release of LH for approximately 60 min. The concentration of cortisol was increased (P less than 0.05) after both doses of FK 33-824, but was unaffected (P greater than 0.5) by morphine or saline. The serum concentration of GH was increased (P less than 0.01) after both doses of FK 33-824 or morphine, but saline was without effect. These results provide evidence of an inhibitory effect of opioid receptor agonists on LH (FK 33-824 and morphine) and a stimulatory effect on cortisol (FK 33-824) and GH (FK 33-824 and morphine) during the follicular phase in heifers. Divergent effects of morphine and FK 33-824 on cortisol observed in this study provide evidence that opioid-induced changes in LH, GH and cortisol result from activation of different opioid receptors.

Oxysterol-induced cell death in human leukemic T-cells correlates with oxysterol binding protein occupancy and is independent of glucocorticoid-induced apoptosis.

In eukaryotic cells oxysterols inhibit cholesterol biosynthesis and cell growth. A potent oxysterol, 25-hydroxycholesterol, was used to investigate the biological effects of oxysterols on three clonal lines of either glucocorticoid-sensitive or -resistant CEM cells, human leukemic T-lymphocytes. In addition, the glucocorticoid sensitivity of an oxysterol-resistant CEM cell line was tested. Oxysterols blocked growth and caused the lysis of cells regardless of their glucocorticoid response. All cells studied herein possessed an oxysterol binding protein with high affinity for 25-hydroxycholesterol. For all clones grown in serum-free medium, the half-maximal cytolytic concentration of 25-hydroxycholesterol (20-40 nM) correlated with its affinity (Kd = approximately 31 nM) for this oxysterol binding protein. Both cholesterol and mevalonate reversed 25-hydroxycholesterol cytotoxicity; 3-6 microM cholesterol or 0.1 mM mevalonate decreased 60 nM 25-hydroxycholesterol cytotoxicity by 50%. This cholesterol or mevalonate reversal appeared possible even after several days of 60 nM oxysterol treatment. The protective effect of cholesterol could be overcome by increasing 25-hydroxycholesterol concentrations. Cholesterol and mevalonate did not prevent glucocorticoid-mediated lymphocytolysis. Furthermore, the oxysterol-resistant line was sensitive to dexamethasone lysis. These data support the hypothesis that oxysterols and glucocorticoids act independently to block the growth of human leukemic lymphoblasts.

Oxysterol sensitive and resistant lymphoid cells: correlation with regulation of cellular nucleic acid binding protein mRNA.

Oxygenated derivatives of cholesterol inhibit cholesterol synthesis, prevent lymphoid cell growth, and evoke cell death. We have employed a novel selection method to isolate M10 cells, a line of oxysterol-resistant cells, from the sensitive clone CEM C7. Concentrations of the potent sterol 25-hydroxycholesterol that occupy the oxysterol binding protein cause cell death in CEM C7, but not in M10 cells. Both cell lines have similar amounts of the oxysterol binding protein with similar affinities for oxysterol. However, in neither line are the levels of oxysterol binding protein mRNA affected by 1 microM 25-hydroxycholesterol. Furthermore, both cells express the cellular nucleic acid binding protein (CNBP), a 7 zinc finger, DNA-binding protein of unknown function, regulated by oxysterols. The levels of CNBP mRNA are significantly reduced by 25-hydroxycholesterol in the sensitive CEM C7 cells, in which the dose response and time course are consistent with occupancy of the oxysterol binding protein by oxysterol and with subsequent cell kill. However, in the resistant M10 cells, CNBP mRNA levels are unaffected by these concentrations of the 25-hydroxycholesterol. Our results suggest a role for CNBP in oxysterol-induced regulation of cell viability and growth.

Glucocorticoids in malignant lymphoid cells: gene regulation and the minimum receptor fragment for lysis.

We have examined clones of human malignant lymphoid cells for markers that correlate with glucocorticoid-mediated cell lysis. In glucocorticoid-sensitive clones of CEM, a human T-cell lymphoblastic leukemia line, two genes correlate with glucocorticoid-induced cell lysis. The glucocorticoid receptor (GR) itself is induced by standard glucocorticoids in sensitive clones and not in insensitive clones. The phenylpyrazolo-glucocorticoid cortivazol (CVZ) is capable of lysing several clones resistant to high concentrations of standard potent glucocorticoids. When these clones were tested for cortivazol responses, they were not only lysed by cortivazol but also showed induction of GR mRNA. Thus receptor induction appears to correlate with the lysis function of receptor in these cells. To determine what parts of the GR are required for lysis, we have mapped this function by transfecting and expressing GR and GR fragment genes in a GR-deficient CEM clone. Our results indicate that none of the known trans-activation regions of the GR are required. Removal of the steroid binding domain gives a fragment that is fully constitutive. Only one and one-half "Zn fingers" of the DNA binding region are required. We also find in CEM cells rapid suppression of the c-myc protooncogene, preceding growth arrest and cell lysis by glucocorticoids. This occurs only in clones possessing both intact receptors and lysis function. Thus the simple presence of GR alone is not sufficient to guarantee c-myc down-regulation. Introduction into the cells of c-myc driven by a promoter that does not permit suppression by glucocorticoids confers resistance to steroids. Furthermore, suppression of c-myc by antisense oligonucleotides also kills the cells. Therefore, c-myc appears to be a pivotal gene related both to ability of steroid to kill and to cell viability.

Glucocorticoid/oxysterol-induced DNA lysis in human leukemic cells.

Both glucocorticoids and oxysterols, steroids with quite different known transduction pathways, cause the death of lymphoid cells. Dual TUNEL/propidium iodide assays on sensitive human leukemic CEM-C7 clones treated with either steroid were clearly positive by 48 h, consistent with apoptosis. Both steroids evoked two distinctive types of DNA lysis: cleavage into large fragments of several different sizes and the classic "ladders", multiples of approximately 200 base pairs. Conventional gel electrophoresis showed that a small proportion of total DNA had undergone laddering 36-48 h after treatment with glucocorticoid or 24 h after oxysterol exposure. On field inversion gel electrophoresis of cellular DNA both steroids caused an increase in an array of large DNA fragments <50 kb in size. A 50 kb fragment appeared 36 h after treatment with either steroid, but only oxysterol treatment caused a significant increase in a 300 kb fragment. Oxysterol treatment did not result in DNA fragmentation in the resistant M10R5 subclone, which retained sensitivity to glucocorticoids. We conclude that glucocorticoids and oxysterols kill these cells with similar, but not identical, patterns of DNA lysis which occur just before or concomitant with the onset of cell death.

Glucocorticoid, interleukin-2, and prostaglandin interactions in a clonal human leukemic T-cell line.

We have studied the growth effects of conditioned media, interleukin-2 and PGE prostaglandin analogs on the glucocorticoid-sensitive human leukemic T-cell clone, CEM-C7. After 4 days, the glucocorticoid dexamethasone at approximately 10 nM kills 50% of CEM-C7 cells. To test the hypothesis that glucocorticoid-mediated lymphocytolysis was due to suppression of lymphokine expression only, we attempted to protect CEM-C7 cells from lysis by provision of lymphokine(s). Conditioned media from interleukin-2 secreting Jurkat T-cells as well as the glucocorticoid-insensitive, but receptor positive clone, CEM-C1, failed to prevent lymphocytolysis; exogenous interleukin-2 also did not provide protection. There were complex, biphasic interactions between dexamethasone and the synthetic PGEs, enisoprost and enisoprost free acid. Low doses of enisoprost alone (0.01 to 1 microgram/ml) stimulated growth, and in combinations completely reversed the growth inhibitory effects of 10 nM dexamethasone. Higher concentrations of enisoprost were inherently lethal and were additive to the steroid effect. Thus the glucocorticoid-induced lymphocytolysis in this human leukemic T-cell line may be modified biphasically by PGE prostaglandins, depending on their concentration. However, interleukin-2 or components in the conditioned media assayed had no effect in ameliorating the lethal response to glucocorticoid.