A Bayesian network meta-analysis comparing concurrent chemoradiotherapy followed by adjuvant chemotherapy, concurrent chemoradiotherapy alone and radiotherapy alone in patients with locoregionally advanced nasopharyngeal carcinoma.

BACKGROUND: Given the lack of studies, whether the addition of adjuvant chemotherapy (AC) to concurrent chemoradiotherapy (CCRT) is superior to CCRT alone for locoregionally advanced nasopharyngeal carcinoma (NPC) remains unclear. The main objective of this Bayesian network meta-analysis was to determine the efficacy of CCRT + AC when compared with CCRT alone. PATIENTS AND METHODS: We systematically searched databases and extracted data from randomized, controlled trials involving NPC patients randomly assigned to receive CCRT + AC, CCRT, or radiotherapy (RT). Overall survival (OS), locoregional recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) with hazard ratios (HRs) were investigated. A Bayesian network for different outcomes was established to incorporate all evidence. Multiple treatment comparisons based on the network integrated the efficacy of CCRT + AC, CCRT, and RT. RESULTS: Eight studies involving 2144 patients were analyzed. In the network meta-analysis, CCRT + AC and CCRT were both significantly better than RT alone for all outcomes, except that no significant difference was found between CCRT and RT for LRFS. Though ranking probabilities showed that CCRT + AC was ranked superior to CCRT for OS, LRFS, and DMFS, no significant differences were found between CCRT+AC and CCRT for all outcomes [OS: HR = 0.86, 95% credible interval (CrI) 0.60-1.16; LRFS: HR = 0.72, 95% CrI 0.43-1.15; DMFS: HR = 0.86, 95% CrI 0.62-1.16]. CONCLUSIONS: No significant improvement was found following CCRT + AC compared with CCRT alone. Whether the omission of additional AC can reduce toxic effects without adversely affecting survival in patients with locoregionally advanced NPC should be further explored, in addition to the precise patient status that would benefit from AC following CCRT.

Comparison of radiological and clinical features of temporal lobe necrosis in nasopharyngeal carcinoma patients treated with 2D radiotherapy or intensity-modulated radiotherapy.

BACKGROUND: To compare the imaging and clinical features of temporal lobe necrosis (TLN) in nasopharyngeal carcinoma (NPC) patients treated with two-dimensional radiotherapy (2D-RT) or those with intensity-modulated radiotherapy (IMRT). METHODS: We retrospectively analysed NPC patients who underwent 2D-RT (72 patients, 128 temporal lobes) or IMRT (36 patients, 50 lobes) and developed radiation-induced, MRI-confirmed TLN. RESULTS: White-matter lesions (WMLs), contrast-enhanced lesions, cysts and local mass effects were present in 128 out of 128 vs 48 out of 50 (P=0.078), 123 out of 128 vs 47 out of 50 (P=0.688), 10 out of 128 vs 1 out of 50 (P=0.185) and 57 out of 128 vs 13 out of 50 (P=0.023) temporal lobes, respectively, in the 2D-RT and IMRT groups. The WMLs were more extensive in the 2D-RT group (P<0.001). The maximum diameter of contrast-enhanced lesions was greater in the 2D-RT group (P<0.001), and these lesions tended to extend far away from the nasopharynx. The WMLs and enhancement had no impact on cyst development (both P=1). Local mass effects were always accompanied with contrast-enhanced lesions (P=0.024) but were not correlated with WMLs or cysts (P=0.523 and 0.341, respectively). There were no between-group differences in clinical features (all P-values>0.05), whereas the difference in the incidence of severe debility was of marginal significance (18.1% vs 5.6%, P=0.077). CONCLUSIONS: The IMRT-induced TLN was less extensive and milder than 2D-RT-induced TLN, but both had similar clinical features.

Prognostic value of magnetic resonance imaging-detected cranial nerve invasion in nasopharyngeal carcinoma.

BACKGROUND: We previously reported that magnetic resonance imaging evidence of cranial nerve invasion was an unfavourable prognostic factor in nasopharyngeal carcinoma. However, the prognostic value of this evidence in nasopharyngeal carcinoma treated with intensity-modulated radiotherapy remains unknown. METHODS: We retrospectively analysed 749 nasopharyngeal carcinoma patients who underwent intensity-modulated radiotherapy. RESULTS: Cranial nerve invasion was observed in 299 (39.9%) patients with T3-4 disease. In T3-4 nasopharyngeal carcinoma, magnetic resonance imaging-detected cranial nerve invasion was associated with inferior 5-year overall survival, distant metastasis-free survival, and locoregional relapse-free survival (P=0.002, 0.003, and 0.012, respectively). Multivariate analyses confirmed that cranial nerve invasion was an independent prognostic factor for distant metastasis-free survival (hazard ratio, 1.927; P=0.019) and locoregional relapse-free survival (hazard ratio, 2.605; P=0.032). Furthermore, the receiver-operating characteristic curves verified that the predictive validity of T classifications was significantly improved when combined with magnetic resonance imaging-detected cranial nerve invasion in terms of death, distant metastasis, and locoregional recurrence (P=0.015, 0.021 and 0.008, respectively). CONCLUSIONS: Magnetic resonance imaging-detected cranial nerve invasion is an independent adverse prognostic factor in nasopharyngeal carcinoma treated with intensity-modulated radiotherapy.

An extended study of seroprevalence of anti-Anisakis simplex IgE antibodies in Norwegian blood donors.

During the last decade, cases of the fish parasite Anisakis simplex infection and allergy in human have increased in countries with high fish consumption. Our aim was to perform an extended seroprevalence study of anti-IgE antibodies against this parasite in Norway, one of the high fish-consuming countries. At the Department of Immunology and Transfusion Medicine and the Laboratory of Clinical Biochemistry, Haukeland University Hospital, Bergen, Norway, two main groups of anonymized serum samples were collected; the first (n = 993) from recently recruited blood donors (designated 'BDO') and the second (n = 414) from patient with total IgE levels ≥1000 kU/l (designated 'IGE+'). The sera were analysed by the ImmunoCAP(®) method for total IgE and IgE antibodies against A. simplex, house dust mite (HDM), shrimp, cod, crab, brine shrimp and shrimp tropomyosin. The A. simplex positive sera were further tested by an enzyme-linked immunosorbent assay (ELISA) method, which uses 2 recombinant (r) major allergens, rAni s 1 and rAni s 7 as target antigens. SDS-PAGE and Western immunoblotting analyses were also performed. Whereas the prevalences by ImmunoCAP(®) were 0.4% and 16.2% in the BDO and IGE+ groups, respectively, analyses with recombinant allergens showed only 0.0% and 0.2%. Cross-reactivity and immunoblotting analyses suggested that most of the ImmunoCAP(®) positive sera were probably false-positive due to cross-sensitization to shrimp and HDM. However, positivity due to other A. simplex antigens should also be considered. Compared with other high fish-consuming countries, we observed a very low seroprevalence of anti-Anisakis IgE antibodies in a Norwegian population.

IgE sensitization to the fish parasite Anisakis simplex in a Norwegian population: a pilot study.

The reports on fish parasite Anisakis simplex allergy have increased in countries with high fish consumption in the last decade. In Norway, a high consumption country, the prevalence of immunoglobulin E (IgE) sensitization to A. simplex was still unknown. Thus, our objective was to investigate the sensitization prevalence in this country. At the Haukeland University Hospital, Bergen, Norway, two main groups of surplus serum samples were collected: one from newly recruited blood donors (BDO) and the other from the Allergy laboratory (ALL) after analysing IgE and IgE antibodies. The latter was divided into three series: one containing unsorted sera and two sorted by either Phadiatop(®) ≥0.35 kU(A)/l or total IgE ≥1000 kU/l. The sera were analysed for total IgE and IgE antibodies against A. simplex, shrimp, house dust mite (HDM), cod and cross-reactive carbohydrates (CCDs). The prevalence of IgE sensitization to A. simplex was 2.0%, 2.2% and 6.6% in BDO, the unsorted and Phadiatop(®) positive serum groups, respectively. A considerable degree of cross-sensitization to shrimp and HDM is further suggested. Unspecific binding because of high total IgE or by binding to CCDs seemed to play a minor role. The prevalence of IgE sensitization to A. simplex appears to be lower in a Norwegian population than in other high fish-consuming countries, but might still be overestimated owing to cross-sensitization.

Acetyl glyceryl ether phosphorylcholine stimulates leukotriene B4 synthesis in human polymorphonuclear leukocytes.

Acetyl glyceryl ether phosphorylcholine (AGEPC) and leukotriene B4 (LTB4) induce concentration-dependent neutrophil aggregation. On a molar basis, LTB4 is approximately 10 to 100 times more potent than AGEPC. AGEPC-induced aggregation is attenuated by two inhibitors of arachidonate lipoxygenation, eicosatetraynoic acid and nordihydroguaiaretic acid, and to a lesser extent by the cyclooxygenase inhibitor, indomethacin. LTB4-induced aggregation is not readily reduced by the above inhibitors of arachidonic acid metabolism. Reverse phase high performance liquid chromatography, coupled with selective ion gas chromatography/mass spectrometry, shows that AGEPC stimulates neutrophils to synthesize sufficient LTB4 to account for the AGEPC response. In addition, the rate of LTB4 biosynthesis in response to AGEPC correlates well with the rate of AGEPC- and/or LTB4-induced neutrophils aggregation, and desensitization experiments indicate that AGEPC and LTB4 cross-desensitize. These data suggest that AGEPC-induced neutrophil aggregation may be mediated by LTB4.

Distinct murine macrophage receptor pathway for human triglyceride-rich lipoproteins.

Murine P388D1 macrophages have a receptor pathway that binds human hypertriglyceridemic very low density lipoproteins (HTG-VLDL) that is fundamentally distinct from the LDL receptor pathway. Trypsin-treated HTG-VLDL (tryp-VLDL), devoid of apolipoprotein (apo)-E, fail to bind to the LDL receptor, yet tryp-VLDL and HTG-VLDL cross-compete for binding to P388D1 macrophage receptors, indicating that these lipoproteins bind to the same sites. The specific, high affinity binding of tryp-VLDL and HTG-VLDL to macrophages at 4 degrees C is equivalent and at 37 degrees C both produce rapid, massive, curvilinear (receptor-mediated) triglyceride accumulation in macrophages. Ligand blots show that P388D1 macrophages express a membrane protein of approximately 190 kD (MBP190) that binds both tryp-VLDL and HTG-VLDL; this binding is competed by HTG-VLDL, trypsinized HTG-VLDL, and trypsinized normal VLDL but not by normal VLDL or LDL. The macrophage LDL receptor (approximately 130 kD) and cellular uptake of beta-VLDL, but not MBP 190 nor uptake of tryp-VLDL, are induced when cells are exposed to lipoprotein-deficient medium and decreased when cells are cholesterol loaded. Unlike the macrophage LDL receptor, MBP 190 partitions into the aqueous phase after phase separation of Triton X-114 extracts. An anti-LDL receptor polyclonal antibody blocks binding of HTG-VLDL to the LDL receptor and blocks receptor-mediated uptake of beta-VLDL by P388D1 cells but fails to inhibit specific cellular uptake of tryp-VLDL or to block binding of tryp-VLDL to MBP 190. Human monocytes, but not human fibroblasts, also express a binding protein for HTG-VLDL and tryp-VLDL similar to MBP 190. We conclude that macrophages possess receptors for abnormal human triglyceride-rich lipoproteins that are distinct from LDL receptors in ligand specificity, regulation, immunological characteristics, and cellular distribution. MBP 190 shares these properties and is a likely receptor candidate for the high affinity uptake of TG-rich lipoproteins by macrophages.

Platelet-derived growth factor does not induce c-fos in NIH 3T3 cells expressing the EJ-ras oncogene.

Platelet-derived growth factor (PDGF), the calcium ionophore A23187, and the tumor promoter phorbol myristate acetate stimulated c-fos mRNA levels in control NIH 3T3 cells. However, NIH 3T3 cells transformed by EJ-ras DNA transfection, which have diminished PDGF-stimulated phospholipase C activity, showed a 95% reduction in PDGF-stimulated c-fos mRNA levels. The responses to A23187 and phorbol myristate acetate were also attenuated, but not as severely as the PDGF-mediated induction. The reduction in PDGF-stimulated c-fos induction did not appear to be a general result of cellular transformation, since src-transformed NIH 3T3 cells displayed a strong PDGF-stimulated c-fos induction. Despite the reduction in PDGF-stimulated c-fos induction, EJ-ras-transformed cells still responded mitogenically to PDGF. These data suggest that the magnitude of c-fos induction cannot be directly correlated with PDGF-stimulated mitogenesis in EJ-ras-transformed NIH 3T3 cells.

RNA synthesis inhibitors alter the subnuclear distribution of DNA topoisomerase I.

The acute effect of RNA and DNA synthesis inhibitors on DNA topoisomerase (topo) I localization within cells was examined. Indirect immunofluorescence revealed that topo I was distributed throughout the nuclei but was concentrated in nucleoli of untreated K562 leukemia cells and A549 non-small cell lung cancer cells. Treatment with the DNA polymerase inhibitor aphidicolin did not alter this distribution. In contrast, 30-60 min after addition of the RNA synthesis inhibitor 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) at concentrations that inhibited [3H]uridine incorporation into RNA by > or = 50%, topo I was visible throughout the nuclei without nucleolar accentuation. Western blotting and activity assays confirmed that the amount of topo I polypeptide and topo I activity were unaltered by the brief DRB treatment. Within 30 min of DRB removal, topo I relocalized to the nucleoli in the absence or presence of the protein synthesis inhibitor cycloheximide. Collectively, these results suggest a reversible translocation of topo I out of the nucleoli when RNA synthesis is inhibited. Treatment with the topo I poisons topotecan or camptothecin, agents that also inhibit RNA synthesis, likewise caused redistribution of topo I to nonnucleolar regions of the nucleus in a variety of cell types. In DC3F hamster lung fibroblasts, 2.5 microM topotecan or 1.25 microM camptothecin was sufficient to cause this topo I redistribution. In DC3F/C-10 cells that contain a mutant camptothecin-resistant topo I, topo I relocalization required 50-fold higher concentrations of topotecan or camptothecin but not DRB. These observations not only suggest that accumulation of topo I in the nucleolus is related to ongoing RNA synthesis but also raise the possibility of screening for some types of camptothecin resistance at the single-cell level using a rapid immunofluorescence-based assay.

Mechanism of interaction of CC-1065 (NSC 298223) with DNA.

CC-1065 (NSC 298223), a potent new antitumor antibiotic produced by Streptomyces zelensis, interacts strongly with double-stranded DNA and appears to exert its cytotoxic effects through disruption of DNA synthesis. We undertook this study to elucidate the sites and mechanisms of CC-1065 interaction with DNA. The binding of CC-1065 to synthetic and native DNA was examined by differential circular dichroism or by Sephadex chromatography with photometric detection. The binding of CC-1065 with calf thymus DNA was rapid, being complete within 2 hr, and saturated at 1 drug per 7 to 11 base pairs. The interaction of CC-1065 with synthetic DNA polymers indicated a specificity for adenine- and thymine-rich sites. Agarose gel electrophoresis of CC-1065-treated supercoiled DNA showed that CC-1065 did not intercalate. Site exclusion studies using substitutions in the DNA grooves showed CC-1065 to bind primarily in the minor groove. CC-1065 did not cause DNA breaks; it inhibited susceptibility of DNA to nuclease S1 digestion. It raised the thermal melting temperature of DNA, and it inhibited the ethidium-induced unwinding of DNA. Thus, in contrast to many antitumor agents, CC-1065 stabilized the DNA helix. DNA helix overstabilization may be relevant to the mechanism of action of CC-1065.

Analysis of the CDKN2A, CDKN2B and CDK4 genes in 48 Australian melanoma kindreds.

Germline mutations within the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene and one of its targets, the cyclin dependent kinase 4 (CDK4) gene, have been identified in a proportion of melanoma kindreds. In the case of CDK4, only one specific mutation, resulting in the substitution of a cysteine for an arginine at codon 24 (R24C), has been found to be associated with melanoma. We have previously reported the identification of germline CDKN2A mutations in 7/18 Australian melanoma kindreds and the absence of the R24C CDK4 mutation in 21 families lacking evidence of a CDKN2A mutation. The current study represents an expansion of these efforts and includes a total of 48 melanoma families from Australia. All of these families have now been screened for mutations within CDKN2A and CDK4, as well as for mutations within the CDKN2A homolog and 9p21 neighbor, the CDKN2B gene, and the alternative exon 1 (E1beta) of CDKN2A. Families lacking CDKN2A mutations, but positive for a polymorphism(s) within this gene, were further evaluated to determine if their disease was associated with transcriptional silencing of one CDKN2A allele. Overall, CDKN2A mutations were detected in 3/30 (10%) of the new kindreds. Two of these mutations have been observed previously: a 24 bp duplication at the 5' end of the gene and a G to C transversion in exon 2 resulting in an M531 substitution. A novel G to A transition in exon 2, resulting in a D108N substitution was also detected. Combined with our previous findings, we have now detected germline CDKN2A mutations in 10/48 (21%) of our melanoma kindreds. In none of the 'CDKN2A-negative' families was melanoma found to segregate with either an untranscribed CDKN2A allele, an R24C CDK4 mutation, a CDKN2B mutation, or an E1beta mutation. The last three observations suggest that these other cell cycle control genes (or alternative gene products) are either not involved at all, or to any great extent, in melanoma predisposition.

Evidence for mediation of acetyl glyceryl ether phosphorylcholine stimulation of adenosine 3',5'-(cyclic)monophosphate levels in human polymorphonuclear leukocytes by leukotriene B4.

Acetyl glyceryl ether phosphorylcholine induces human neutrophil aggregation. Incubation of neutrophils with either prostaglandin I2, or the cyclic AMP-dependent phosphodiesterase inhibitor, RO 20-1724 before the addition of PAF-acether attenuates subsequent aggregation. Paradoxically, a small elevation in cyclic AMP is observed coincident with the initiation of PAF-acether-stimulated aggregation. The elevation in cyclic AMP in response to PAF-acether is amplified by RO 20-1724, and the magnitude of the response is dependent upon the concentration of PAF-acether. The elevation in cyclic AMP is not due to prostaglandins, because indomethacin actually enhances the elevation in cyclic AMP induced by PAF-acether. The involvement of the neutrophil 5-lipoxygenase, and subsequent leukotriene B4 synthesis, is suggested by the observation that 5-lipoxygenase inhibitors limit both the elevation in cyclic AMP induced by PAF-acether, and the indomethacin enhancement. This indirect evidence is supported by the fact that leukotriene B4 itself elevates neutrophil cyclic AMP levels in intact cells, and stimulates the adenylate cyclase in broken cell preparations. Although the elevation in cyclic AMP induced by either PAF-acether or leukotriene B4 is coincident with the onset of neutrophil aggregation, it is not obligatory for aggregation. The adenylate cyclase inhibitor 2',5'-dideoxyadenosine blocks the PAF-acether-stimulated increase in cyclic AMP, and actually enhances aggregation. It is suggested that the increase in cyclic AMP observed after the addition of PAF-acether is due to concomitant leukotriene B4 synthesis, and is not obligatory for neutrophil aggregation, but is actually part of a feed-back regulatory system through which PAF-acether and leukotriene B4 can limit their own activity in neutrophils.

Receptor-specific targeting mediated by the coexpression of a targeted murine leukemia virus envelope protein and a binding-defective influenza hemagglutinin protein.

The entry of retroviral vectors into cells requires two events: binding to a cell surface receptor and the subsequent fusion of viral and cellular membranes. The host range of a vector is therefore determined largely by the receptor specificity of the fusion protein contained in the outer viral envelope. Previous attempts to generate targeted retroviral vectors have included the addition of targeting ligands to the murine leukemia virus envelope protein (MuLV Env). Although such proteins frequently display modified cell-binding characteristics, the interaction with the targeted receptors fails to trigger virus-cell fusion. Here, we report the use of a binding-defective but fusion-competent hemagglutinin (HA) protein to complement the fusion defect in a chimeric MuLV Env targeted to the Flt-3 receptor. Retroviral vectors containing both proteins showed enhanced transduction of cells expressing Flt-3, which was abrogated by preincubating the target cells with soluble Flt-3 ligand. Furthermore, the fusion function of HA was absolutely required. These data demonstrate that it is possible to separate the binding and fusion events of retroviral entry, using two separate proteins, and suggest that varying the binding protein component in this scheme may allow a general strategy for targeting retroviral vectors.

Elevated serum interleukin-6 (IL-6) and IL-6 receptor concentrations in posttraumatic stress disorder following accidental man-made traumatic events.

BACKGROUND: Recently, it has been reported that serum interleukin-1 beta (IL-1 beta), but not soluble IL-2 receptor (sIL-2R), concentrations were significantly higher in patients with posttraumatic stress disorder (PTSD) than in normal volunteers, and that psychological stress in humans is associated with increased secretion of proinflammatory cytokines, such as IL-6. METHODS: The aim of the present study was to examine the inflammatory response system in patients with PTSD through measurements of serum IL-6, sIL-6R, sgp130 (the IL-6 signal transducing protein), sIL-1R antagonist (sIL-1RA; an endogenous IL-1 receptor antagonist), CC16 (an endogenous anticytokine), and sCD8 (the T suppressor-cytotoxic antigen). RESULTS: Serum IL-6 and sIL-6R, but not sgp130, sIL-RA, CC16, or sCD8, concentrations were significantly higher in PTSD patients than in normal volunteers. Serum sIL-6R concentrations were significantly higher in PTSD patients with concurrent major depression than in PTSD patients without major depression and normal volunteers. There were no significant relationships between serum IL-6 or sIL-6R and severity measures of PTSD. CONCLUSIONS: The results suggest that PTSD is associated with increased IL-6 signaling. It is hypothesized that stress-induced secretion of proinflammatory cytokines is involved in the catecholaminergic modulation of anxiety reactions.

Peripheral markers of serotonergic and noradrenergic function in post-pubertal, caucasian males with autistic disorder.

Some studies have suggested that disorders in the peripheral and central metabolism of serotonin (5-HT) and noradrenaline may play a role in the pathophysiology of autistic disorder. This study examines serotonergic and noradrenergic markers in a study group of 13 male, post-pubertal, caucasian autistic patients (age 12-18 y; I.Q. > 55) and 13 matched volunteers. [3H]-paroxetine binding Kd values were significantly higher in patients with autism than in healthy volunteers. Plasma concentrations of tryptophan, the precursor of 5-HT, were significantly lower in autistic patients than in healthy volunteers. There were no significant differences between autistic and normal children in the serum concentrations of 5-HT, or the 24-hr urinary excretion of 5-hydroxy-indoleacetic acid (5-HIAA), adrenaline, noradrenaline, and dopamine. There were no significant differences in [3H]-rauwolscine binding Bmax or Kd values, or in the serum concentrations of tyrosine, the precursor of noradrenaline, between both study groups. There were highly significant positive correlations between age and 24-hr urinary excretion of 5-HIAA and serum tryptophan. The results suggest that: 1) serotonergic disturbances, such as defects in the 5-HT transporter system and lowered plasma tryptophan, may play a role in the pathophysiology of autism; 2) autism is not associated with alterations in the noradrenergic system; and 3) the metabolism of serotonin in humans undergoes significant changes between the ages of 12 and 18 years.

Negative immunoregulatory effects of antidepressants: inhibition of interferon-gamma and stimulation of interleukin-10 secretion.

There is now some evidence that major depression is accompanied by activation of the inflammatory response system. There is also some evidence that antidepressants may suppress the release of cytokines, such as interleukin-1 beta (IL-1 beta) and IL-6 by activated monocytes and IL-2 and interferon-gamma (IFN gamma) by activated T cells. This study was carried out to examine the effects of clomipramine, sertraline, and trazodone on the stimulated production of IFN gamma, a pro-inflammatory cytokine, and IL-10, a negative immunoregulatory cytokine. Whole blood of nine healthy volunteers was stimulated with PHA, 5 micrograms/mL and LPS, 25 micrograms/mL for 72 hr with and without incubation with clomipramine, 10(-6) and 10(-9) M, sertraline, 10(-6) and 10(-8) M, and trazodone, 10(-6) and 10(-8) M. All three antidepressants significantly reduced IFN gamma secretion, whereas clomipramine and sertraline significantly increased IL-10 secretion in culture supernatant. All three antidepressants significantly reduced the IFN gamma/IL-10 ratio. The results suggest that antidepressants, at concentrations in the therapeutical range, have negative immunoregulatory effects through inhibition of IFN gamma and stimulation of IL-10 release.

Serotonergic and noradrenergic markers of post-traumatic stress disorder with and without major depression.

Some studies have suggested that disorders in the peripheral and central metabolism of serotonin (5-HT) and noradrenaline (NE) may play roles in the pathophysiology of post-traumatic stress disorder (PTSD). This study examines (1) the availability of plasma total tryptophan, the precursor of 5-HT, and tyrosine, the precursor of NE; and (2) the platelet 5-HT transporter and alpha 2-adrenoceptor (alpha 2-AR) binding sites in patients with PTSD and healthy volunteers. High-performance liquid chromatography (HPLC) was employed to measure plasma tryptophan and tyrosine as well as amino acids known to compete with the same cerebral transport system; that is, valine, leucine, phenylalanine, and isoleucine. The maximum number of binding sites (Bmax) and their affinity (Kd) for binding to [3H]-paroxetine and [3H]-rauwolscine, a selective alpha 2-AR antagonist, were determined. [3H]-paroxetine and [3H]-rauwolscine binding Kd values were significantly higher in patients with PTSD than in healthy volunteers. [3H]-rauwolscine binding Kd values were significantly higher in patients with PTSD and concurrent major depression (MD) than in PTSD patients without MD and healthy volunteers. Plasma tyrosine concentrations and the ratio of tyrosine/valine + leucine + isoleucine + phenylalanine + tryptophan were significantly higher in PTSD patients with MD than in those without MD and healthy volunteers. The results show that PTSD is accompanied by lower affinity of paroxetine binding sites and that PTSD with concurrent MD is accompanied by lower affinity of alpha 2-ARs and increased plasma tyrosine availability to the brain. The results suggest that (1) serotonergic mechanisms, such as defects in the 5-HT transporter system, may play a role in the pathophysiology of PTSD; and (2) that catecholaminergic mechanisms, such as increased precursor availability and lowered affinity of alpha 2-ARs, may play a role in the pathophysiology of PTSD with concurrent MD.

The effect of population density on the development of experimental atherosclerosis in female mice.

The effect of cage population density on plasma lipids and the development of atherosclerosis was examined in female C57BL/6 mice. Mice were housed at a density of one, two or five animals per cage and fed an atherogenic diet for 28 weeks. Subsequently, the animals were bled, sacrificed, the hearts removed and the extent of fatty lesion development in the aorta examined and quantified. As the population density increased, there was a statistically significant increase in total cholesterol levels, VLDL+LDL cholesterol levels, the VLDL+LDL/HDL ratio and lesion severity. These differences are due to the psychosocial stress associated with living within a confined space with high population density over an extended period of time.

Synthesis and biological evaluation of antiplatelet 2-aminochromones.

The synthesis and biological evaluation of a series of antiplatelet 2-morpholinylchromones has been described. Modification of the C-7 phenylmethoxy group of 8-methyl-7-(phenylmethoxy)-2-(4-morpholinyl)-4H-1-benzopyran-4-one (2) has led to the discovery of a series of 7-[(amino-ethyl)oxy]-8-methyl derivatives which are potent inhibitors of ADP-induced platelet aggregation. Several members of this class proved active in preventing platelet-dependent thrombus formation in the dog, including 8-methyl-7-[2-(4-methyl-1-piperazinyl)ethoxy]-2-(4- morpholinyl)-4H-1-benzopyran-4-one (39) which was devoid of hemodynamic effects at the effective antithrombotic dose.

Immune activation in the early puerperium is related to postpartum anxiety and depressive symptoms.

The pathophysiology of the postpartum blues, common transient mood disorders in the first week postpartum, has remained elusive. Recently, however, it has been shown that depression and anxiety disorders are accompanied by activation of the inflammatory response system (IRS). This study was developed to determine whether the postnatal blues is associated with IRS activation. Serum concentrations of interleukin-6 (IL-6), IL-6 receptor (IL-6R), gp130 (the IL-6 signaling protein), IL-1R antagonist (IL-1RA) and leukemia inhibitory factor receptor (LIFR) were assayed in 22 nonpregnant women and in 91 pregnant women before delivery and 1 and 3 days after delivery. On each occasion the parturient women completed the State version of the Spielberger State-Trait-Anxiety-Inventory (STAI) and the Zung Depression Rating Scale (ZDS). Serum IL-6, IL-1RA and LIFR were significantly higher in pregnant women at the end of term than in nonpregnant women.