Kras mutation rate precisely orchestrates ductal derived pancreatic intraepithelial neoplasia and pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death in the United States. Despite the high prevalence of Kras mutations in pancreatic cancer patients, murine models expressing the oncogenic mutant Kras (Krasmut) in mature pancreatic cells develop PDAC at a low frequency. Independent of cell of origin, a second genetic hit (loss of tumor suppressor TP53 or PTEN) is important for development of PDAC in mice. We hypothesized ectopic expression and elevated levels of oncogenic mutant Kras would promote PanIN arising in pancreatic ducts. To test our hypothesis, the significance of elevating levels of K-Ras and Ras activity has been explored by expression of a CAG driven LGSL-KrasG12V allele (cKras) in pancreatic ducts, which promotes ectopic Kras expression. We predicted expression of cKras in pancreatic ducts would generate neoplasia and PDAC. To test our hypothesis, we employed tamoxifen dependent CreERT2 mediated recombination. Hnf1b:CreERT2;KrasG12V (cKrasHnf1b/+) mice received 1 (Low), 5 (Mod) or 10 (High) mg per 20 g body weight to recombine cKras in low (cKrasLow), moderate (cKrasMod), and high (cKrasHigh) percentages of pancreatic ducts. Our histologic analysis revealed poorly differentiated aggressive tumors in cKrasHigh mice. cKrasMod mice had grades of Pancreatic Intraepithelial Neoplasia (PanIN), recapitulating early and advanced PanIN observed in human PDAC. Proteomics analysis revealed significant differences in PTEN/AKT and MAPK pathways between wild type, cKrasLow, cKrasMod, and cKrasHigh mice. In conclusion, in this study, we provide evidence that ectopic expression of oncogenic mutant K-Ras in pancreatic ducts generates early and late PanIN as well as PDAC. This Ras rheostat model provides evidence that AKT signaling is an important early driver of invasive ductal derived PDAC.

Inverse 4D conformal planning for lung SBRT using particle swarm optimization

A critical aspect of highly potent regimens such as lung stereotactic body radiation therapy (SBRT) is to avoid collateral toxicity while achieving planning target volume (PTV) coverage. In this work, we describe four dimensional conformal radiotherapy using a highly parallelizable swarm intelligence-based stochastic optimization technique. Conventional lung CRT-SBRT uses a 4DCT to create an internal target volume and then, using forward-planning, generates a 3D conformal plan. In contrast, we investigate an inverse-planning strategy that uses 4DCT data to create a 4D conformal plan, which is optimized across the three spatial dimensions (3D) as well as time, as represented by the respiratory phase. The key idea is to use respiratory motion as an additional degree of freedom. We iteratively adjust fluence weights for all beam apertures across all respiratory phases considering OAR sparing, PTV coverage and delivery efficiency. To demonstrate proof-of-concept, five non-small-cell lung cancer SBRT patients were retrospectively studied. The 4D optimized plans achieved PTV coverage comparable to the corresponding clinically delivered plans while showing significantly superior OAR sparing ranging from 26% to 83% for D max heart, 10%-41% for D max esophagus, 31%-68% for D max spinal cord and 7%-32% for V 13 lung.

Risk factors for overweight and overfatness in rural South African children and adolescents

Background

To determine risk factors for overweight/overfatness in children and adolescents from rural KwaZulu-Natal, South Africa.

Methods

Anthropometric data were collected from a cross-sectional sample (n = 1519, ages 7, 11 and 15 years) and linked to demographic information (n = 1310 and n = 1317 in overweight and overfat analyses, respectively). Candidate risk factors for overweight/overfatness were identified and tested for associations with overweight (BMI-for-age >+1SD, WHO reference) and overfatness (>85th centile body fatness, McCarthy reference) as outcomes. Associations were examined using simple tests of proportions (χ²/Mann–Whitney U tests) and multivariable logistic regression.

Results

Sex was a consistent variable across both analyses; girls at significantly increased risk of overweight and overfatness (overweight: n = 180, 73.9 and 26.1% females and males, respectively (P < 0.0001); overfat: n = 187, 72.7 and 27.3% females and males, respectively (P < 0.0001)). In regression analyses, sex and age (defined by school grade) were consistent variables, with boys at lower risk of overweight (adjusted odds ratio (AOR) 0.40 (confidence interval (CI) -0.28–0.57)) and risk of overweight increasing with age (AOR 0.65 (CI- 0.44–0.96), 0.50 (CI-0.33–0.75) and 1.00 for school grades 1, 5 and 9, respectively). Results were similar for overfatness.

Conclusions

This study suggests that pre-adolescent/adolescent females may be the most appropriate targets of future interventions aimed at preventing obesity in rural South Africa.

Use of mid-upper arm circumference for determining overweight and overfatness in children and adolescents

OBJECTIVE

To assess the use of mid-upper arm circumference (MUAC) for identification of overweight and overfatness in rural South African children and adolescents.

METHODS

Anthropometric data (weight, height, MUAC and % body fat) from a cross-sectional sample of 978 black South African 5-14-year-olds were analysed. Receiver operating characteristic (ROC) curve analysis determined the validity of MUAC as a proxy for determining overweight and overfatness.

FINDINGS

Area under the curve (AUC) results were generally high. Boys and girls aged 10-14 years had ROC-AUC for overfatness classed as 'excellent', 0.97 and 0.98 respectively. Cut-points in the MUAC distribution which optimised the ROC-AUC for identification of overfatness and obesity were determined for boys and girls aged 5-9 and 10-14 years, and had high sensitivity and specificity.

CONCLUSIONS

MUAC may have potential for clinical and surveillance applications as an accurate yet simple and widely available indicator of overweight and overfatness in children and adolescents in resource-poor settings.

Use of dried blood spots for the determination of genetic variation of interleukin-10, killer immunoglobulin-like receptor and HLA class I genes

Optimal methods for using dried blood spots (DBSs) for population genetics-based studies have not been well established. Using DBS stored for 8 years from 21 pregnant South African women, we evaluated three methods of gDNA extraction with and without whole-genome amplification (WGA) to characterize immune-related genes: interleukin-10 (IL-10), killer immunoglobulin-like receptors (KIRs) and human leukocyte antigen (HLA) class I. We found that the QIAamp DNA mini kit yielded the highest gDNA quality (P< 0.05; Wilcoxon signed rank test) with sufficient yield for subsequent analyses. In contrast, we found that WGA was not reliable for sequence-specific primer polymerase chain reaction (SSP-PCR) analysis of KIR2DL1, KIR2DS1, KIR2DL5 and KIR2DL3 or high-resolution HLA genotyping using a sequence-based approach. We speculate that unequal template amplification by WGA underrepresents gene repertoires determined by sequence-based approaches.

An evaluation of the effect of an educational intervention for Australian social workers on competence in delivering brief cognitive behavioural strategies: a randomised controlled trial

Background

Broad community access to high quality evidence-based primary mental health care is an ongoing challenge around the world. In Australia one approach has been to broaden access to care by funding psychologists and other allied health care professionals to deliver brief psychological treatments to general practitioners' patients. To date, there has been a scarcity of studies assessing the efficacy of social worker delivered psychological strategies. This study aims to build the evidence base by evaluating the impact of a brief educational intervention on social workers' competence in delivering cognitive behavioural strategies (strategies derived from cognitive behavioural therapy).

Methods

A randomised controlled trial design was undertaken with baseline and one-week follow-up measurement of both objective and self-perceived competence. Simulated consultations with standardised depressed patients were recorded on videotape and objective competence was assessed by blinded reviewers using the Cognitive Therapy Scale. Questionnaires completed by participants were used to measure self-perceived competence. The training intervention was a 15 hour face-to-face course involving presentations, video example consultations, written materials and rehearsal of skills in pairs.

Results

40 Melbourne-based (Australia) social workers enrolled and were randomised and 9 of these withdrew from the study before the pre training simulated consultation. 30 of the remaining 31 social workers (97%) completed all phases of the intervention and evaluation protocol (16 from intervention and 14 from control group). The intervention group showed significantly greater improvements than the control group in objective competence (mean improvement of 14.2 (7.38-21.02) on the 66 point Cognitive Therapy Scale) and in subjective confidence (mean improvement of 1.28 (0.84-1.72) on a 5 point Likert scale). On average, the intervention group improved from below to above the base competency threshold on the Cognitive Therapy Scale whilst the control group remained below.

Conclusions

Social workers can attain significant improvements in competency in delivering cognitive behavioural strategies from undertaking brief face to face training. This is relevant in the context of health reforms that involve social worker delivery of evidence based psychological care. Further research is required to assess how these improvements in competence translate into performance in practice and clinical outcomes for patients.

Activity-dependent secretion of neuronal activity regulated pentraxin from vasopressin neurons into the systemic circulation

Neuronal activity regulated pentraxin (Narp) is a secreted, synaptic protein that has been implicated in modulating synaptic transmission. However, it is unclear how Narp secretion is regulated. Since we noted prominent Narp immunostaining in vasopressin neurons of the hypothalamus and in the posterior pituitary, we assessed whether it, like vasopressin, is released into the systemic circulation in an activity-dependent fashion. Consistent with this hypothesis, electron microscopic studies of the posterior pituitary demonstrated that Narp is located in secretory vesicles containing vasopressin. Using affinity chromatography, we detected Narp in plasma and found that these levels are markedly decreased by hypophysectomy. In addition, we confirmed that injection of a viral Narp construct into the hypothalamus restores plasma Narp levels in Narp knockout mice. In checking for activity-dependent secretion of Narp from the posterior pituitary, we found that several stimuli known to trigger vasopressin release, i.e. hypovolemia, dehydration and endotoxin, elevate plasma Narp levels. Taken together, these findings provide compelling evidence that Narp is secreted from vasopressin neurons in an activity-dependent fashion.

Regulation of vitamin D-1alpha-hydroxylase in a human cortical collecting duct cell line

BACKGROUND

Recent studies have shown that renal expression of 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-OHase) is not restricted to proximal tubules. To investigate the significance of this expression, we characterized the regulation of 1alpha-OHase expression and activity in a human cortical collecting duct cell line (HCD).

METHODS

Expression of 1alpha-OHase mRNA and protein was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analyses. Enzyme activity was quantified using 25-hydroxyvitamin D3 as the substrate; conversion to 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and 24,25-dihydroxyvitamin D3 was then determined by thin-layer chromatography.

RESULTS

HCD cells expressed mRNA and protein for 1alpha-OHase. However, basal 1,25(OH)2D3 production was lower than that observed in proximal tubule HKC-8 cells. In both cell lines, synthesis of 1,25(OH)2D3 was increased by forskolin, parathyroid hormone, and low calcium medium. Conversely, treatment with 1,25(OH)2D3 itself decreased 1alpha-OHase activity. This effect was more pronounced in HCD cells, which also demonstrated significantly higher levels of 24-hydroxylase activity. The most striking induction of 1alpha-OHase activity was observed in the HCD cells following incubation with lipopolysaccharide, which was coincident with the expression of mRNA for both CD14 and Toll-like receptor 4.

CONCLUSIONS

These results highlight the capacity for synthesis of 1,25(OH)2D3 in cells from more distal areas of the nephron. However, more sensitive feedback regulation and immune induction of 1alpha-OHase in the HCD cells suggest a more localized role for 1,25(OH)2D3 production in the distal nephron.

Expression of 11 beta-hydroxysteroid dehydrogenase in rat osteoblastic cells: pre-receptor regulation of glucocorticoid responses in bone

11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) acts as a pre-receptor signaling mechanism for corticosteroids by regulating the access of active glucocorticoids to both glucocorticoid (GR) and mineralocorticoid receptors (MR). To examine the relationship between endogenous glucocorticoid metabolism and osteoblast function, we have characterized the expression of 11 beta-HSD isozymes in rat osteosarcoma cells. Analysis of mRNA from ROS 25/1, UMR 106 and ROS 17/2.8 cells revealed transcripts for both 11 beta-HSD type 1 (11 beta-HSD1) and type 2 (11 beta-HSD2) in all three cell lines. However, enzyme activity studies showed only high affinity dehydrogenase activity (inactivation of corticosterone (B) to 11-dehydrocorticosterone (A)), characteristic of 11 beta-HSD2; conversion of B to A was higher in ROS 25/1> UMR 106 cells>ROS 17/2.8. Although all three cell lines had similar numbers of GR (50,000/cell), glucocorticoid modulation of alkaline phosphatase activity and cell proliferation was only detectable in ROS 17/2.8 cells. Further studies showed that 11 beta-HSD2 activity in each of the cells was potently stimulated by both A and B, but not by synthetic dexamethasone. This effect was blocked by the 11 beta-HSD inhibitor, 18 beta-glycyrrhetinic acid (but not by GR or MR antagonists) suggesting direct, allosteric regulation of 11 beta-HSD2 activity. These data indicate that in osteosarcoma cells 11 beta-HSD2 plays a key role in controlling GR-mediated responses; cells with relatively high levels of 11 beta-HSD2 activity were insensitive to glucocorticoids, whilst cells with low levels showed functional responses to both dexamethasone and B. In addition to the established effects of 11 beta-HSD2 in protecting MR in the kidney and colon, our data suggest that 11 beta-HSD2 in bone represents an important pre-receptor mechanism in determining ligand availability to GR.

Progressive muscle relaxation and secretory immunoglobulin A

30 healthy students produced saliva samples for Immunoglobulin A assay before and after sessions involving either progressive muscle relaxation (n = 15) or a control condition (n = 15). Levels of immunoglobulin A increased significantly in the relaxation group but not in the control group.

Modulation of 11beta-hydroxysteroid dehydrogenase isozymes by proinflammatory cytokines in osteoblasts: an autocrine switch from glucocorticoid inactivation to activation

Tissue damage by proinflammatory cytokines is attenuated at both systemic and cellular levels by counter anti-inflammatory factors such as corticosteroids. Target cell responses to corticosteroids are dependent on several factors including prereceptor regulation via local steroidogenic enzymes. In particular, two isozymes of 11beta-hydroxysteroid dehydrogenase (11beta-HSD), by interconverting hormonally active cortisol (F) to inactive cortisone (E), regulate the peripheral action of corticosteroids 11beta-HSD1 by converting E to F and 11beta-HSD2 by inactivating F to E. In different in vitro and in vivo systems both 11beta-HSD isozymes have been shown to be expressed in osteoblasts (OBs). Using the MG-63 human osteosarcoma cell-line and primary cultures of human OBs, we have studied the regulation of osteoblastic 11beta-HSD isozyme expression and activity by cytokines and hormones with established roles in bone physiology. In MG-63 cells, interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) potently inhibited 11beta-HSD2 activity (cortisol-cortisone conversion) and messenger RNA (mRNA) levels in a dose-dependent manner while stimulating reciprocal expression of 11beta-HSD1 mRNA and activity (cortisone-cortisol conversion). A similar rise in 11beta-HSD1 reductase activity also was observed in primary cultures of OBs treated with 10 ng/ml TNF-alpha. Pretreatment of MG-63 cells with 0.1 ng/ml IL-1beta resulted in increased cellular sensitivity to physiological glucocorticoids as shown by induction of serum and glucocorticoid-inducible kinase (SGK; relative increase with 50 nM F but no IL-1beta pretreatment 1.12 +/- 0.34; with pretreatment 2.63 +/- 0.50; p < 0.01). These results highlight a novel mechanism within bone cells whereby inflammatory cytokines cause an autocrine switch in intracellular corticosteroid metabolism by disabling glucocorticoid inactivation (11beta-HSD2) while inducing glucocorticoid activation (11beta-HSD1). Therefore, it can be postulated that some of the effects of proinflammatory cytokines within bone (e.g., periarticular erosions in inflammatory arthritis) are mediated by this mechanism.

Extrarenal expression of 25-hydroxyvitamin d(3)-1 alpha-hydroxylase

The mitochondrial enzyme 25-hydroxyvitamin D(3)-1 alpha-hydroxylase (1 alpha-hydroxylase) plays an important role in calcium homeostasis by catalyzing synthesis of the active form of vitamin D, 1,25-dihydroxyvitamin D(3), in the kidney. However, enzyme activity assays indicate that 1 alpha-hydroxylase is also expressed in a variety of extrarenal tissues; recent cloning of cDNAs for 1 alpha-hydroxylase in different species suggests that a similar gene product is found at both renal and extrarenal sites. Using specific complementary ribonucleic acid probes and antisera to 1 alpha-hydroxylase, we have previously reported the distribution of messenger ribonucleic acid and protein for the enzyme along the mouse and human nephron. Here we describe further immunohistochemical and Western blot analyses that detail for the first time the extrarenal distribution of 1 alpha-hydroxylase in both normal and diseased tissues. Specific staining for 1 alpha-hydroxylase was detected in skin (basal keratinocytes, hair follicles), lymph nodes (granulomata), colon (epithelial cells and parasympathetic ganglia), pancreas (islets), adrenal medulla, brain (cerebellum and cerebral cortex), and placenta (decidual and trophoblastic cells). Further studies using psoriatic skin highlighted overexpression of 1 alpha-hydroxylase throughout the dysregulated stratum spinosum. Increased expression of skin 1alpha-hydroxylase was also associated with sarcoidosis. In lymph nodes and skin from these patients 1 alpha-hydroxylase expression was observed in cells positive for the surface antigen CD68 (macrophages). The data presented here confirm the presence of protein for 1 alpha-hydroxylase in several extrarenal tissues, such as skin, placenta, and lymph nodes. The function of this enzyme at novel extrarenal sites, such as adrenal medulla, brain, pancreas, and colon, remains to be determined. However, the discrete patterns of staining in these tissues emphasizes a possible role for 1 alpha-hydroxylase as an intracrine modulator of vitamin D function in peripheral tissues.

1alpha-Hydroxylase and the action of vitamin D

The active form of vitamin D, 1,25-dihydroxvitamin D(3) (1, 25(OH)(2)D(3)), is a pleiotropic hormone whose actions include the regulation of calcium homeostasis, control of bone cell differentiation and modification of immune responses. Synthesis of 1, 25(OH)(2)D(3) from the major circulating metabolite, 25-hydroxyvitamin D(3) (25(OH)D(3)), is catalysed by a mitochondrial cytochrome P450 enzyme, 25-hydroxyvitamin D-1alpha-hydroxylase (1alpha-OHase). Although 1alpha-OHase is expressed predominantly in the kidney, extra-renal production of 1,25(OH)(2)D(3) has also been demonstrated in tissues such as lymph nodes and skin. The tight regulation of 1alpha-OHase which occurs in both renal and peripheral tissues has made studies of the expression and regulation of this enzyme remarkably difficult. However, the recent cloning of mouse, rat and human cDNAs for 1alpha-OHase (CYP1alpha/Cyp1alpha) has enabled a more thorough characterization of this enzyme. In particular, analysis of the CYP1alpha gene has identified mutations causing the inherited disorder vitamin D-dependent rickets type 1, also known as pseudo-vitamin D deficiency rickets. Studies from our own group have focused on the distribution of 1alpha-OHase in both renal and extra-renal tissues. Data indicate that the enzyme is expressed throughout the nephron, suggesting discrete endocrine and paracrine/autocrine functions. Further immunohistochemical analyses have shown that the enzyme is widely distributed in extra-renal tissues, and this appears to be due to the same gene product as the kidney. Collectively, these observations have raised important new questions concerning the role of 1alpha-OHase in vitamin D signalling at a local level. The relationship between expression of protein for 1alpha-OHase and enzyme activity has yet to be fully characterized and may be dependent on membrane proteins such as megalin. Similarly, elucidation of the mechanisms involved in differential regulation of renal and extra-renal 1,25(OH)(2)D(3) production will be essential to our understanding of the tissue-specific functions of 1alpha-OHase. These and other issues are discussed in the current review.

Expression and functional consequences of 11beta-hydroxysteroid dehydrogenase activity in human bone

Glucocorticoids have an essential role in skeletal development and function but are detrimental in excess. In several tissues, glucocorticoid action is dependent upon the expression of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) isozymes, which interconvert active cortisol (F) and inactive cortisone (E). We previously demonstrated the expression of 11beta-HSD isozymes in human osteosarcoma cell lines, osteoblast cultures, and fetal bone. We now characterize 11beta-HSD expression in adult human bone using specific antihuman 11beta-HSD antibodies, riboprobes, and enzyme activity studies. In addition, the effect of 11beta-HSD on bone metabolism in vivo was assessed using the 11beta-HSD inhibitor carbenoxolone in eight normal male volunteers. In fresh normal human bone tissue, both 11beta-dehydrogenase (cortisol-to-cortisone conversion) and reductase (cortisone-to-cortisol conversion) activities were demonstrated. There was considerable interindividual variation in the dehydrogenase, but not reductase, activity. In bone homogenates, activity was NADP-dependent with a K(m) for F of 4.8 +/- 1.2 micromol/L, suggesting the presence of 11beta-HSD1. This was confirmed by reverse transcription-polymerase chain reaction (RT-PCR) analysis. Immunohistochemistry and in situ hybridization studies demonstrated 11beta-HSD1 isozyme expression in cells of the osteoblast lineage and in osteoclasts. The 11beta-HSD2 isozyme was expressed, but only in osteoblasts and at a low level. Ingestion of 300 mg of carbenoxolone by eight normal volunteers for 7 days resulted in a significant decrease in the bone resorption markers, pyridinoline (Pyr) and deoxypyridinoline (DPyr) (change in urinary Pyr/creatinine -1.55 +/- 0.55 [mean +/- SE], for DPyr/creatinine -0. 4 +/- 0.14 nmol/mmol; p < 0.05 for both), with no overall change in the bone formation markers C- and N-terminal propeptides of type I collagen (PICP and PINP). These data suggest that local tissue metabolism of glucocorticoids is likely to be important in determining the sensitivity of both osteoblasts and osteoclasts to glucocorticoids. In particular, variation in 11beta-HSD isozyme expression and activity may explain individual variation in susceptibility to glucocorticoid-induced osteoporosis.

Steroid hormone receptor expression and action in bone

The skeleton is a complex tissue, and hormonal control of bone remodelling is elaborate. The important role that steroid hormones play in bone cell development and in the maintenance of normal bone architecture is well established, but it is only relatively recently that it has become possible to describe their precise mechanism of action. This review focuses not only on the steroid hormones (oestrogens, corticosteroids, androgens and progesterone), but also on related hormones (vitamin D, thyroid hormone and the retinoids), all of which act via structurally homologous nuclear receptors that form part of the steroid/thyroid receptor superfamily. By examining the actions of all of these hormones in vivo and in vitro, this review gives a general overview of the current understanding of steroid hormone action in bone. In addition, a comprehensive review of steroid hormone receptor expression in bone cells is included. Finally, the role that future developments, such as steroid hormone receptor knockout mice, will play in our understanding of steroid hormone action in bone is considered.

Expression of 25-hydroxyvitamin D3-1alpha-hydroxylase along the nephron: new insights into renal vitamin D metabolism

Renal synthesis of the active form of vitamin D, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], is a pivotal step in calcium and phosphate homeostasis. Production of 1,25(OH)2D3 is catalyzed by the mitchondrial cytochrome P450, 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-HYD). As a consequence of the tight regulation of vitamin D metabolism during normal physiology, studies of the expression and regulation of 1alpha-HYD have proved remarkably difficult. However, the recent cloning of the gene for 1alpha-HYD has enabled a more comprehensive analysis of the tissue distribution of 1alpha-HYD, as well as the mechanisms involved in controlling 1,25(OH)2D3 production. In particular, an understanding of site-specific expression and regulation of 1alpha-HYD along the nephron might help to elucidate a more versatile role for 1,25(OH)2D3 in renal physiology.

Estradiol formation by human osteoblasts via multiple pathways: relation with osteoblast function

The importance of estrogens in bone metabolism is illustrated by the accelerated bone loss and increase in osteoporotic fractures associated with postmenopausal estrogen deficiency. In this study, the expression and activity of the enzymes involved in estrogen metabolism in human osteoblastic cells were investigated in relation to differentiation of these cells. PCR reactions using mRNA from an in vitro differentiating human cell line (SV-HFO) were performed to assess mRNA expression of the enzymes aromatase, different subtypes of 17beta-hydroxysteroid dehydrogenase (17beta-HSD), and steroid sulfatase. Aromatase, sulfatase, and 17beta-HSD type 2 and 4 were found to be expressed throughout differentiation. Expression of 17beta-HSD type 3, however, was relatively weak, except for early time points in differentiation. Type 1 17beta-HSD expression was not detected. Aromatase activity decreased during differentiation, as was demonstrated by the conversion of androstenedione (A) and testosterone (T) into estrone (E(1)) and estradiol (E(2)), respectively. The 17beta-HSD isozymes catalysing a reductive reaction convert androstenedione and estrone into testosterone and estradiol, respectively. Their activity declined with differentiation. Analysis of 17beta-HSD activity indicated both oxidative (E(2) to E(1); T to A) and reductive (E(1) to E(2); A to T) metabolism at all stages of osteoblast differentiation. Both activities declined as cells moved toward a differentiating mineralizing phenotype. However, the oxidative reaction was increasingly in favor of the reductive reaction at all times during differentiation. Sulfatase activity, as demonstrated by the conversion of estrone-sulfate into estrone, was constant during differentiation. In conclusion, we have demonstrated that all enzymes necessary for estrogen metabolism are expressed and biologically active in differentiating human osteoblasts. The activity of aromatase and 17beta-HSD was found to be dependent on the stage of cell differentiation. In addition, human osteoblasts effectively convert estradiol into estrone. The efficacy of osteoblasts to synthesize estradiol may determine the ultimate change in rate of bone turnover after menopause, as well as the development of osteoporosis. Moreover, the enzymes involved in the metabolism of estradiol may form a target for intervention.

Expression of 25-hydroxyvitamin D3-1alpha-hydroxylase in the human kidney

The secosteroid hormone 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plays a vital role in calcium metabolism, tissue differentiation, and normal bone growth. Biosynthesis of 1,25(OH)2D3 is catalyzed by the mitochondrial cytochrome P450 enzyme 25-hydroxyvitamin D3 1alpha-hydroxylase (1alpha-hydroxylase). Although activity of this enzyme has been described in several tissues, the kidneys are recognized to be the principal site of 1,25(OH)2D3 production. To date, enzyme activity studies using vitamin D-deficient animals have suggested that 1alpha-hydroxylase is expressed exclusively in proximal convoluted tubules. With the recent cloning of 1alpha-hydroxylase, specific cRNA probes and in-house polyclonal antiserum have been used to determine the distribution of 1alpha-hydroxylase along the human nephron. Immunohistochemistry and in situ hybridization studies indicated strong expression of 1alpha-hydroxylase protein and mRNA in the distal convoluted tubule, the cortical and medullary part of the collecting ducts, and the papillary epithelia. Lower expression was observed along the thick ascending limb of the loop of Henle and Bowman's capsule. Weaker and more variable expression of 1alpha-hydroxylase protein and mRNA was seen in proximal convoluted tubules, and no expression was observed in glomeruli or vascular structures. These data show for the first time the distribution of alpha1-hydroxylase expression in normal human kidney. In contrast to earlier enzyme activity studies conducted in vitamin D-deficient animals, our data indicate that the distal nephron is the predominant site of 1alpha-hydroxylase expression under conditions of vitamin D sufficiency.

Dating violence at three time periods: 1976, 1992, and 1996

Data collected over the past 10 years were used to investigate whether there have been changes in the incidence of violence when dating reported at a large university. Responses to Straus's 1979 Conflict Tactics Scale in 1986 (n = 603), 1992 (n = 414), and 1996 (n = 571) were compared. Analyzes indicated that there has been a reduction in both verbal aggression and violence scores over the 10-yr. period. In addition, the percentage of respondents who reported being in nonviolent relationships increased while the percentage of respondents in the three categories of relationship that include violence (mutual, perpetrator, and victim) decreased. These findings indicate that there may be an over-all reduction in both verbal aggression and violence between dating partners as they attempt to resolve conflicts.

Characterization of 11beta-hydroxysteroid dehydrogenase activity and corticosteroid receptor expression in human osteosarcoma cell lines

Studies in vitro and in vivo have shown that corticosteroids play an important role in bone physiology and pathophysiology. It is now established that corticosteroid hormone action is regulated, in part, at the pre-receptor level through the expression of isozymes of 11beta-hydroxysteroid dehydrogenase (11beta-HSD), which are responsible for the interconversion of hormonally active cortisol to cortisone. In this report we demonstrate 11beta-HSD activity in human osteoblast (OB) cells. Osteosarcoma-derived OB cell lines TE-85, MG-63 and SaOS-2 and fibrosarcoma Hs913T cells express the type 2 isoform of 11beta-HSD, as determined by reverse transcription polymerase chain reaction (RT-PCR) and specific enzyme assays. Enzyme activity was shown to be strictly NAD dependent with a Km of approximately 71 nM; 11beta-HSD type 1 mRNA expression and enzyme activity were not detected. All four cell lines expressed mRNA for the glucocorticoid receptor (GR) and mineralocorticoid receptor, but specific binding was only detectable with radiolabelled dexamethasone (Kd=10 nM) and not aldosterone. MG-63 cells had two to three times more GR than the other OB cells, which correlated with the higher levels of 11beta-HSD 2 activity in these cells. In contrast to the osteosarcoma cell studies, RT-PCR analysis of primary cultures of human OB cells revealed the presence of mRNA for 11beta-HSD 1 as well as 11beta-HSD 2. However, enzyme activity in these cells remained predominantly oxidative, i.e. inactivation of cortisol to cortisone (147 pmol/h per mg protein at 500 nM cortisol) was greater than cortisone to cortisol (10.3 pmol/h per mg protein at 250 nM cortisone). Data from normal human OB and osteosarcoma cells demonstrate the presence of an endogenous mechanism for inactivation of glucocorticoids in OB cells. We postulate that expression of the type 1 and type 2 isoforms of 11beta-HSD in human bone plays an important role in normal bone homeostasis, and may be implicated in the pathogenesis of steroid-induced osteoporosis.

Constitutive expression of 25-hydroxyvitamin D3-1alpha-hydroxylase in a transformed human proximal tubule cell line: evidence for direct regulation of vitamin D metabolism by calcium

Circulating levels of the active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) are dependent on activity of the renal mitochondrial cytochrome P450 enzyme, 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-hydroxylase). Production of 1,25-(OH)2D3 occurs predominantly in the renal proximal tubule, with 1alpha-hydroxylase activity being impaired in renal insufficiency and renal disease. The expression and activity of 1alpha-hydroxylase are tightly regulated in response to serum levels of PTH, calcium, phosphate, and 1,25-(OH)2D3 itself. As a consequence of this, the characterization of 1alpha-hydroxylase in human renal tissue has proved difficult. In this study we have characterized constitutive 1alpha-hydroxylase expression in a simian virus 40-transformed human proximal tubule cell line, HKC-8. Initial analyses of [3H]25-hydroxyvitamin D3 (25OHD3) metabolism in these cells using straight and reverse phase HPLC revealed product peaks that coincided with authentic 1,25-(OH)2D3 as well as 24,25-dihydroxyvitamin D3 (24,25-(OH)2D3). Enzyme kinetic studies indicated that the Km for synthesis of 1,25-(OH)2D3 in HKC-8 cells was 120 nmol/liter 25OHD3, with a maximum velocity of 21 pmol/h/mg protein. This activity was inhibited by treatment with ketoconazole, but not diphenyl phenylenediamine. RT-PCR analysis of RNA from HKC-8 cells revealed a transcript similar in size to that observed in keratinocytes and primary cultures of human proximal tubule cells, and protein was detected by Western blot analysis. Synthesis of 1,25-(OH)2D3 was up regulated by treatment with forskolin (10 micromol/liter, 24 h) and was down-regulated by 1,25-(OH)2D3 (10 nmol/liter, 24 h). 1Alpha-hydroxylase activity in HKC-8 cells was also sensitive to the concentration of calcium. Cells grown in low calcium (0.5 mmol/liter) showed a 4.8-fold induction of 1alpha-hydroxylase, whereas treatment with medium containing high levels of calcium (2 mmol/liter) significantly inhibited 1,25-(OH)2D3 production. These data suggest that direct effects of calcium on proximal tubule cells may be an important feature of the regulation of renal 1,25-(OH)2D3 production.

Differential RNA display identifies novel genes associated with decreased vitamin D receptor expression

To characterize further the function of the intracellular vitamin D receptor (VDR), we have developed stable transfectant variants of a vitamin D-responsive cell line (U937) which express either decreased or increased numbers of VDR. In this study we have analyzed changes in gene expression associated with this variable VDR expression. Initial experiments indicated that a 50% decrease in VDR levels was associated with a 2-fold increase in cell proliferation and a similar rise in c-myc mRNA expression. Further studies were carried out using differential RNA display (DD). Sequence analysis of DD products revealed two cDNAs with identity to known gene products: the catalytic sub-unit of DNA-protein kinase (DNA-PK(CS)), and the peroxisomal enzyme 17beta-hydroxysteroid dehydrogenase type IV (17beta-HSD IV). Northern analysis confirmed that expression of both mRNAs was reduced in cells with decreased numbers of VDR. Down-regulation of 17beta-HSD IV mRNA expression was associated with enhanced estradiol inactivation by U937 cells, suggesting a link between estrogenic pathways and cell proliferation. Further Northern analyses indicated that there was no significant change in 17beta-HSD IV or DNA-PK(CS) mRNA levels following treatment with 1,25(OH)2D3, although expression of both genes varied with changes in cell proliferation. These data suggest that, in addition to its established role as a hormone-dependent trans-activator, VDR may influence gene expression by ligand-independent mechanisms.

Characterization of aromatase and 17 beta-hydroxysteroid dehydrogenase expression in rat osteoblastic cells

Postmenopausal loss of 17 beta-estradiol (E2) in women is associated with decreased bone mineral density and increased susceptibility to osteoporotic bone fracture. These changes in bone status are assumed to be due to circulating levels of the hormone; therapeutic replacement of E2 can alleviate the bone disease. However, recent reports have shown that human osteoblastic (OB) cells are able to synthesize estrogens locally, via expression of the enzyme aromatase. In this study, we have characterized the expression and activity of aromatase and 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) in rat OB cell lines. Aromatase activity in ROS 17/2.8, ROS 25/1, and UMR 106 cells was similar to that shown in human OB cells, with the highest levels of activity observed in the more differentiated ROS 17/2.8 cells (Vmax = 45 pmol/h/mg of protein). The rat OB cells also showed 17 beta-HSD activity, with the predominant metabolism in all three cell lines being estrone (E1) to E2. As with aromatase, the highest activity was observed in ROS 17/2.8 cells (Vmax = 800 pmol/h/mg of protein). Northern analyses indicated the variable presence of transcripts corresponding to the type 1, 2, 3, and 4 isoforms of 17 beta-HSD. Further analysis of androstenedione metabolism indicated that the net effect of aromatase and 17 beta-HSD activity varied with cell type and culture treatment. All three OB cell lines were able to synthesize E1, E2, and testosterone from androstenedione, although activity varied between OB cell types. Regulatory effects were observed with 1,25-dihydroxyvitamin D3 (positive) and dexamethasone (negative). These data suggest that local synthesis of sex hormones is an important function of OB cells and may play a key role in the modulation of bone turnover independent of circulating hormone concentrations.

1,25-dihydroxyvitamin D3 regulates estrogen metabolism in cultured keratinocytes

Local estrogen metabolism may play an important role in modulating cell development in peripheral tissues such as breast, adipose, and bone. C19 androgens are converted to C18 estrogens by the enzyme aromatase, overexpression of which is associated with breast cancer. Interconversion of active estradiol (E2) to inactive estrone is controlled by various isoforms of the enzyme 17beta-hydroxysteroid dehydrogenase (17betaHSD). We have studied the expression of these two enzymes in human keratinocytes and report rapid changes in 17betaHSD activity in response to treatment with 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Keratinocytes cultured in serum-free medium showed aromatase activity of 2.5 fmol/h x mg cell protein, which was unaffected by any culture treatment. A much higher level of 17betaHSD activity was observed in the keratinocytes, predominantly conversion of E2 to estrone (approximately 120 pmol/h x mg cell protein). This inactivation of E2 increased in a dose-dependent fashion after treatment of the cells with antiproliferative doses of 1,25-(OH)2D3 (0.1-200 nM). The effect of 1,25-(OH)2D3 on 17betaHSD activity was enhanced by simultaneous treatment with dexamethasone, which also increased the antiproliferative action of 1,25-(OH)2D3. Reverse transcription-PCR and Northern analysis showed that keratinocytes expressed messenger RNA for three 17betaHSD isoenzymes (types I, II, and IV). Treatment with 1,25-(OH)2D3 (10 nM for 20 h) resulted in the up-regulation of messenger RNA levels for type 2 17betaHSD. Further RNA studies combined with E2 binding experiments demonstrated the presence of estrogen receptors in the cultured keratinocytes. These data indicate that keratinocytes are potential targets for systemically or locally produced estrogens, which may, in turn, play a key role in the development of normal skin. In particular, we propose that 17betaHSD isoenzymes are key target genes for 1,25-(OH)2D3 in keratinocytes and may be an important feature of the antipsoriatic effects of vitamin D and its analogs.

Thyroid hormone, vitamin D and retinoid receptor expression and signalling in primary cultures of rat osteoblastic and immortalised osteosarcoma cells

3,5,3'-Tri-iodothyronine (T3), 1 alpha,25(OH)2-vitamin D3 (D3) and retinoids activate related nuclear receptors which interact by heterodimerisation to regulate gene expression. Actions of each hormone are discrete and may be specified by changes in the relative concentrations of their receptors (T3R, vitamin D receptor (VDR), retinoic acid receptor (RAR), retinoid X receptor (RXR)). T3, D3 and retinoids are essential for skeletal development and maintenance and we have previously shown complex interactions amongst their signalling pathways in osteosarcoma cells. In these studies we demonstrate that similar T3R, VDR, RAR and RXR proteins are co-expressed in both osteoblast lineage cell primary cultures and osteosarcoma cells by Western blotting. We investigated whether hormone interactions in bone result from changes in receptor stoichiometry. Cells were treated with combinations of T3, D3, 9-cis retinoic acid (9-cis RA) and all-trans retinoic acid (RA) that are known from previous studies to produce complex cell specific responses. No alteration in expression of any receptor protein was seen in response to any hormone combination in three phenotypically distinct osteosarcoma cell lines. Thus, in contrast to studies of overexpressed receptors in vitro, changes in the physiological concentrations of endogenous T3R, VDR, RAR and RXR do not specify discrete hormone actions in osteoblastic cells. Other unidentified factors are likely to modulate hormone action in these bone cells.

Moclobemide versus fluoxetine in the treatment of major depressive disorder in adults

The objective of the present study was to compare the safety and efficacy of moclobemide versus fluoxetine in adult patients with major depressive disorder. The design of the study was a multicenter, double-blind, comparative, and randomized trial. A 1- to 2-week single-blind placebo washout phase was followed by 6 weeks of double-blind treatment with moclobemide or fluoxetine. A total of 150 patients were enrolled in the study. There were 128 patients eligible to be randomized, with 66 patients receiving moclobemide and 62 patients receiving fluoxetine. At the termination of the study, patients in the moclobemide group were receiving a mean dose of 440 mg +/- 123 mg, while the mean dose in the fluoxetine group was 35 mg +/- 8 mg. No significant treatment differences were found for any of the efficacy parameters. Headache and nausea were the most frequently reported adverse events in both treatment groups. Headache and blurred vision were reported significantly more often (P < 0.05) in the fluoxetine group, whereas significantly more dry mouth was reported (P < 0.05) in the moclobemide group. These results provide supporting evidence of the comparable efficacy of moclobemide and fluoxetine and the better tolerability of moclobemide when used in the treatment of major depressive disorder.

Psychiatric manifestations of multiple sclerosis: a review

OBJECTIVE

To report the occurrence, type, causes, and management of psychiatric manifestations in multiple sclerosis (MS).

METHOD

Review of recent, relevant literature.

RESULTS

Psychiatric illness, especially depression, occurs much more frequently than expected in patients with MS, is frequently unrecognized or ignored, and is treatable using standard methods, although patients with MS may be unusually sensitive to side effects of tricyclic antidepressants.

CONCLUSIONS

Research is needed to better define the causes of psychiatric syndromes in patients with MS. Those treating MS should increase their awareness of and sensitivity to the likelihood of psychiatric disorder in these patients.

Retinoids modify regulation of endogenous gene expression by vitamin D3 and thyroid hormone in three osteosarcoma cell lines

1 alpha,25-Dihydroxyvitamin D3 (D3), T3, and retinoids are necessary for normal skeletal development, and their actions are interdependent due to the heterodimerization capabilities of their receptors. We investigated the hypothesis that these hormones act on osteoblasts directly to produce complex target gene responses resulting from multiple hormone interactions. Physiological interactions among D3, T3, and retinoid signaling were analyzed in serum-free cultures of the osteosarcoma cell lines ROS 25/1, UMR106, and ROS 17/2.8. These cells express distinct stages of the osteoblast phenotype and coexpress appropriate hormone receptors. Regulation of collagen I alpha 1 and alpha 2, alkaline phosphatase, osteopontin, and osteocalcin messenger RNAs was dependent on the dose and duration of hormone stimulation and modified by cell confluence. Retinoids were required for comprehensive expression of phenotypic responses to D3 and T3 in each cell type and hormone interactions were both cell and target gene specific. Differing responses of target genes in each cell line may provide a molecular basis for discrete hormone actions seen at specific stages of osteoblast differentiation or skeletal development.

Investigating discharge destinations for schizophrenic patients

An audit of hospital records of 542 patients diagnosed as having schizophrenia discharged in the years 1986-88 from the Princess Alexandra Hospital, Brisbane, showed that 46% of patients left hospital to live with other family members, usually parents or spouses. Analysis of destination suggested that the extent of patient-family connectedness increases when the patient is younger, has had fewer admissions, or has had the illness for a shorter period of time.

Characterization of thyroid hormone (T3) receptors in three osteosarcoma cell lines of distinct osteoblast phenotype: interactions among T3, vitamin D3, and retinoid signaling

T3 is required for normal skeletal development, but its cellular targets in bone are unknown. T3 regulates target gene transcription via a specific nuclear receptor (T3R), which can heterodimerize with 9-cis-retinoic acid, 1 alpha, 25-dihydroxyvitamin D3, or retinoic acid receptors to modify T3 responsiveness. Serum-free cultures were developed to investigate hormone interactions in three osteosarcoma cell lines, ROS25/1, UMR106, and ROS17/2.8, that express fibroblast-like, preosteoblast, and mature osteoblast phenotypes. ROS25/1 expressed T3R alpha 1, but only low levels of T3R beta 1, whereas UMR106 and ROS17/2.8 cells expressed both receptor proteins. All cells expressed c-erb-A alpha 2 protein and equal levels of 1 alpha,25-dihydroxyvitamin D3 receptor, 9-cis-retinoic acid receptor, and retinoic acid receptor messenger RNAs. Endogenous T3R activity and the effects of D3 and 9-cis-RA on T3 responsiveness were determined in transfections using reporter genes containing T3 response elements from rat malic enzyme or alpha-myosin heavy chain genes. Cell-specific T3 responses were associated with differing patterns of T3R gene expression and stages of osteoblast phenotype expression. A change in T3R beta 1 gene expression during osteoblast phenotype differentiation may modify T3 action in developing bone.

Sex differences in rates of depression: cross-national perspectives

Rates of depression are compared by sex in epidemiologic surveys conducted in the United States, Canada, Germany and New Zealand. These surveys used similar sampling and diagnostic techniques and the data were standardized to the age and sex distribution of the USA to facilitate comparisons. Data show that the rates of major depression and dysthymia are higher in females than in males and are approximately equal for bipolar disorder across all four countries. The mean age of onset of major depression did not differ by sex across the four countries. The rates of major depression for males seem to be rising and for females stabilizing for birth cohorts born after 1945 (World War II). New data from the National Comorbidity Survey which has younger birth cohorts can directly examine this issue.

A survey of aspirin use in the pre-hospital treatment of suspected acute cardiac chest pain

Recent large studies have demonstrated the value of early intervention with aspirin and thrombolysis in myocardial infarction for patients reaching hospital alive. Management of patients with suspected myocardial infarction prior to hospitalisation is an important area of acute cardiac care. Guidelines for good practice suggest the early administration of aspirin should be considered when an infarct seems likely. We have found aspirin less commonly used than other interventions prior to hospital admission in patients with suspected acute cardiac pain.

Pharmacokinetics of pirmenol in young and elderly subjects

The steady state pharmacokinetics of pirmenol was compared in twelve healthy young (aged 18 to 45 y) and 11 elderly subjects (over 65 y) subjects given pirmenol HCl 100 mg every 12 h for a total of 14 doses. In addition, the single-dose pharmacokinetics of pirmenol was determined following a 100 mg oral dose in the young subject group for comparison with the results of repeated administration. In the young subjects, the mean single-dose and steady-state CLR of pirmenol were similar; however, Ae was 29% higher and CL/f was 22% lower at steady state than after the single dose. Steady-state (fourteenth dose) Cmin, Cmax, tmax, lambda z, Ae, CL/f, CLR and V values were similar in the young and elderly subjects. Based on pharmacokinetic considerations, the dosage of pirmenol is unlikely to differ in young and elderly subjects.

Patent ductus arteriosus increases lung fluid filtration in preterm lambs

Previous studies showed that increased pulmonary blood flow from a patent ductus arteriosus had little or no effect on the amount of fluid in the lungs of mechanically ventilated preterm lambs. The purpose of this study was to examine the effect of a patent ductus arteriosus on lung vascular permeability and to see whether increased pulmonary lymph flow might compensate for the increased rate of fluid filtration. Using a model that allows mechanical control of ductus patency, we studied the effects of increased pulmonary blood flow on lung vascular pressures in six mechanically ventilated premature lambs at 136 +/- 2 d gestation (mean +/- SD) (term = 145 d). We measured lung lymph flow and protein concentrations in lymph and plasma to assess pulmonary vascular fluid filtration and protein permeability. We studied each lamb during sequential steady state periods, first with the ductus open and then with it closed. When the ductus was open, pulmonary blood flow was twice what it was when the ductus was closed. Mean pulmonary artery pressure and left ventricular end-diastolic pressure were greater with the ductus open [40 +/- 5 torr (5.3 +/- 0.7 kPa) and 8 +/- 3 torr (1.1 +/- 0.4 kPa), respectively] than when it was closed [24 +/- 3 torr (3.2 +/- 0.4 kPa) and 4 +/- 2 torr (0.5 +/- 0.3 kPa), respectively]. When the ductus was open, lymph flow was 68% greater and lymph protein concentration was 17% lower than when the ductus was closed. Lymph protein clearance (lymph flow x lymph protein concentration/plasma protein concentration) was 39% greater when the ductus was open.(ABSTRACT TRUNCATED AT 250 WORDS)

Fasting urinary calcium/creatinine and hydroxyproline/creatinine values in young women with amenorrhoea and in matched eumenorrhoeic controls

The present study was undertaken to compare fasting urinary calcium/creatinine (Ca/Cr) and hydroxyproline/creatinine (HP/Cr) values in young amenorrhoeic women with those of age and weight-matched menstruating women and to see whether restoration of menstruation would influence values. Thirty amenorrhoeic patients were matched with 30 controls. Higher Ca/Cr (0.393 (SD 0.213) vs 0.142 (0.89), p less than 0.001) and HP/Cr (0.025 (0.005) vs 0.020 (0.007), p less than 0.005) values were found in patients with hyperprolactinaemia or hypothalamic dysfunction associated with weight loss, anorexia nervosa or excessive exercise (n = 20), suggesting excessive bone loss in these amenorrhoeic patients, who are frequently oestrogen deficient. Furthermore when 9 amenorrhoeic patients with hypothalamic dysfunction became eumenorrhoeic their urinary Ca/Cr values fell (p less than 0.02). However, amenorrhoeic patients with polycystic ovaries (n = 10) had similar Ca/Cr and HP/Cr values as their controls. It is therefore probable that amenorrhoeic patients with polycystic ovaries are not at risk of osteopenia. The present findings suggest measurements of fasting urinary Ca/Cr and HP/Cr values are likely to prove useful in identifying patients with amenorrhoea who are rapidly losing bone, and in assessing their responses to therapy.

Understanding family variables in outcome research in schizophrenia

Outcome studies in schizophrenia research consistently show the importance of family variables in predicting patient relapse. The concept of expressed emotion (EE) is clinically relevant, though concerns remain about its precise meaning. The history of the EE studies is reviewed in the light of other family research, and an alternative model of family emotional environment is proposed. A number of clinical implications are considered.