Innovative strategies to improve diabetes outcomes in disadvantaged populations

Diabetes disproportionately affects disadvantaged populations. Eighty percent of deaths directly caused by diabetes occurred in low- and middle-income countries. In high-income countries, there are marked disparities in diabetes control among racial/ethnic minorities and those with low socio-economic status. Innovative, effective and cost-effective strategies are needed to improve diabetes outcomes in these populations. Technological advances, peer educators and community health workers have expanded methodologies to reach, educate and monitor individuals with diabetes. In the present manuscript we review the outcomes of these strategies, and describe the barriers to and facilitators of these approaches for improving diabetes outcomes.

Successful self-management among non-insulin-treated adults with Type 2 diabetes: a self-regulation perspective

AIMS

To clarify the role of self-monitoring of blood glucose (SMBG) in the self-management of Type 2 diabetes from the patient's perspective, using in-depth interviews with non-insulin-treated adults to investigate how they learned to manage their diabetes effectively and whether SMBG played a significant role in this process.

METHODS

Individual interviews were conducted with 14 non-insulin-treated adults with Type 2 diabetes who had significantly improved their glycaemic control [64% women; 50% black; 21% Hispanic; mean age 60 years; mean HbA(1c) concentration 43 mmol/mol (6.1%)]. Interviews were transcribed and analysed by a coding team, applying the concept of illness coherence from the Common Sense Model of Self-Regulation.

RESULTS

The majority of participants relied on SMBG to evaluate their self-management efforts. Key themes included: adopting an experimental approach; experiencing 'a-ha' moments; provider-assisted problem-solving; using SMBG and other feedback to evaluate when their efforts were working; and normalizing diabetes-specific behaviour changes as being healthy for everyone.

CONCLUSIONS

Our qualitative data are consistent with the argument that SMBG, if implemented appropriately with enough education and provider access, can be a powerful tool for non-insulin-treated adults with Type 2 diabetes to monitor their self-management. Establishing sufficient conditions for illness coherence to develop while individuals are learning to use SMBG could increase their sense of personal control in managing a complex and demanding illness.

Osteoarthritis year 2013 in review: imaging

PURPOSE

To review recent original research publications related to imaging of osteoarthritis (OA) and identify emerging trends and significant advances.

METHODS

Relevant articles were identified through a search of the PubMed database using the query terms "OA" in combination with "imaging", "radiography", "MRI", "ultrasound", "computed tomography", and "nuclear medicine"; either published or in press between March 2012 and March 2013. Abstracts were reviewed to exclude review articles, case reports, and studies not focused on imaging using routine clinical imaging measures.

RESULTS

Initial query yielded 932 references, which were reduced to 328 citations following the initial review. MRI (118 references) and radiography (129 refs) remain the primary imaging modalities in OA studies, with fewer reports using computed tomography (CT) (35 refs) and ultrasound (23 refs). MRI parametric mapping techniques remain an active research area (33 refs) with growth in T2*- and T1-rho mapping publications compared to prior years. Although the knee is the major joint studied (210 refs) there is interest in the hip (106 refs) and hand (29 refs). Imaging continues to focus on evaluation of cartilage (173 refs) and bone (119 refs).

CONCLUSION

Imaging plays a major role in OA research with publications continuing along traditional lines of investigation. Translational and clinical research application of compositional MRI techniques is becoming more common driven in part by the availability of T2 mapping data from the Osteoarthritis Initiative (OAI). New imaging techniques continue to be developed with a goal of identifying methods with greater specificity and responsiveness to changes in the joint, and novel functional neuroimaging techniques to study central pain. Publications related to imaging of OA continue to be heavily focused on quantitative and semiquantitative MRI evaluation of the knee with increasing application of compositional MRI techniques in the hip.

Novel H6PDH mutations in two girls with premature adrenarche: 'apparent' and 'true' CRD can be differentiated by urinary steroid profiling

CONTEXT

Inactivating mutations in the enzyme hexose-6-phosphate dehydrogenase (H6PDH, encoded by H6PD) cause apparent cortisone reductase deficiency (ACRD). H6PDH generates cofactor NADPH for 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1, encoded by HSD11B1) oxo-reductase activity, converting cortisone to cortisol. Inactivating mutations in HSD11B1 cause true cortisone reductase deficiency (CRD). Both ACRD and CRD present with hypothalamic-pituitary-adrenal (HPA) axis activation and adrenal hyperandrogenism.

OBJECTIVE

To describe the clinical, biochemical and molecular characteristics of two additional female children with ACRD and to illustrate the diagnostic value of urinary steroid profiling in identifying and differentiating a total of six ACRD and four CRD cases.

DESIGN

Clinical, biochemical and genetic assessment of two female patients presenting during childhood. In addition, results of urinary steroid profiling in a total of ten ACRD/CRD patients were compared to identify distinguishing characteristics.

RESULTS

Case 1 was compound heterozygous for R109AfsX3 and a novel P146L missense mutation in H6PD. Case 2 was compound heterozygous for novel nonsense mutations Q325X and Y446X in H6PD. Mutant expression studies confirmed loss of H6PDH activity in both cases. Urinary steroid metabolite profiling by gas chromatography/mass spectrometry suggested ACRD in both cases. In addition, we were able to establish a steroid metabolite signature differentiating ACRD and CRD, providing a basis for genetic diagnosis and future individualised management.

CONCLUSIONS

Steroid profile analysis of a 24-h urine collection provides a diagnostic method for discriminating between ACRD and CRD. This will provide a useful tool in stratifying unresolved adrenal hyperandrogenism in children with premature adrenarche and adult females with polycystic ovary syndrome (PCOS).

Measurements of medication adherence in diabetic patients with poorly controlled HbA(1c)

AIMS

To assess pharmacy claims and self-report data as measures of medication adherence and to describe baseline characteristics of subjects in the Improving Diabetes Outcomes Study.

METHODS

Multi-ethnic, lower-income, insured adults (n = 526) in New York City with Type 2 diabetes were enrolled in a randomized, controlled, behavioural intervention study delivered by telephone. Baseline data were examined, including glycated haemoglobin (HbA(1c)), objective measures of diabetes medication adherence [claims data medication possession ratio (MPR)], and two self-report measures [Morisky Medication-taking Scale and the medication-taking item of the Summary of Diabetes Self-Care Activities (SDSCA)]. Associations of highest tertile HbA(1c) (>or= 9.3%) with lowest tertile MPR (< 42%) were assessed with logistic regression models adjusting for potential confounders. Subset analyses were performed based on assessment of potential interaction.

RESULTS

Participants (mean +/- sd age 56 +/- 7 years) had median (interquartile range) HbA(1c) 8.6% (8.0-10.0). Correlations of baseline MPR with Morisky score and SDSCA medication-taking item were strongly significant (both rho = 0.21, P < 0.001). Lowest MPR was significantly (P = 0.008) associated with highest HbA(1c) in the group as a whole and among the subset taking two or more oral glucose-lowering agents (OGLA) (P = 0.002), but not among the subset taking only one (P = 0.83). Self-report adherence measures were not significantly associated with HbA(1c) in either the whole group or either subset.

CONCLUSIONS

These results support the validity of MPR as an adherence measure for OGLA among insured diabetes patients with poorly controlled HbA(1c), especially those taking two or more OGLA.

Elevated cerebrospinal fluid (CSF) leptin in idiopathic intracranial hypertension (IIH): evidence for hypothalamic leptin resistance?

OBJECTIVE

The aetiology of idiopathic intracranial hypertension (IIH) is not known, but its association with obesity is well-recognized. Recent studies have linked obesity with abnormalities in circulating inflammatory and adiposity related cytokines. The aim of this study was to characterize adipokine and inflammatory cytokine profiles in IIH.

DESIGN

Paired serum and cerebrospinal fluid (CSF) specimens were collected from 26 patients with IIH and compared to 62 control subjects. Samples were analysed for leptin, resistin, adiponectin, insulin, IL-1beta, IL-6, IL-8 (CXCL8), TNFalpha, MCP-1 (CCL2), hepatocyte growth factor, nerve growth factor and PAI-1 using multiplex bead immunoassays.

RESULTS

CSF leptin was significantly higher in patients with IIH (P = 0.001) compared to controls after correction for age, gender and body mass index (BMI). In the control population, BMI correlated with serum leptin (r = 0.34; P = 0.007) and CSF leptin (r = 0.51; P < 0.0001), but this was not the case for the IIH population. Profiles of other inflammatory cytokines and adipokines did not differ between IIH patients and controls once anthropometric factors had been accounted for.

CONCLUSIONS

IIH was characterized by significantly elevated CSF leptin levels which did not correlate with BMI. We suggest that CSF leptin may be important in the pathophysiology of IIH and that obesity in IIH may occur as a result of hypothalamic leptin resistance.

11beta-Hydroxysteroid dehydrogenase type 1 regulates insulin and glucagon secretion in pancreatic islets

AIMS/HYPOTHESIS

Exposure to excess glucocorticoid is associated with pancreatic beta cell damage and decreased glucose-stimulated insulin secretion (GSIS). Inactive glucocorticoids (cortisone, 11-dehydrocorticosterone) are converted to active cortisol and corticosterone by 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), which requires NADPH as cofactor, which is generated by hexose-6-phosphate dehydrogenase (H6PDH). We investigated the localisation and activity of 11beta-HSD1 within pancreatic islets, and determined its functional role in the regulation of insulin and glucagon secretion.

METHODS

mRNA expression of 11beta-HSD1 (also known as HSD11B1), glucocorticoid receptor and H6PDH (also known as H6PD) in human pancreas and murine islets was examined by real-time PCR. 11beta-HSD1 protein levels were examined by immunohistochemistry and immunofluorescence. 11beta-HSD1 activity was assessed in intact tissue and isolated islets of wild-type (WT) and both 11beta-Hsd1- and H6pdh-null mice. Glucagon secretion and insulin secretion were analysed by RIA and ELISA respectively in isolated murine islets incubated with dexamethasone.

RESULTS

11beta-HSD1 co-localised with glucagon in the periphery of murine and human islets, but not with insulin or somatostatin. Dexamethasone, 11-dehydrocorticosterone and corticosterone induced a dose-dependent decrease in GSIS and glucagon secretion following low glucose stimulation. Reduction of 11beta-HSD1 activity with specific inhibitors or in experiments carried out in H6pdh-null mice reversed the effects of 11-dehydrocorticosterone, but had no effect following treatment with corticosterone.

CONCLUSIONS/INTERPRETATION

Local regeneration of glucocorticoid via 11beta-HSD1 within alpha cells regulates glucagon secretion and in addition may act in a paracrine manner to limit insulin secretion from beta cells.

The corticosteroid metabolic profile of the mouse

Data are presented on the urinary corticosteroid metabolic profile of the mouse strain 129/svJ. Through the use of GC/MS we have characterized, or tentatively identified corticosterone (Kendall's compound B) metabolites of both the 11beta-hydroxy and 11-carbonyl (compound A) series in urine. Full mass spectra of the methyloxime-trimethylether derivatives of 15 metabolites are included in the paper as an aid to other researchers in the field. Metabolites ranged in polarity from tetrahydrocorticosterone (THB) to dihydroxy-corticosterone with dominance of highly polar steroids. We found that prior to excretion corticosterone can undergo oxidation at position 11beta, reduction at position 20 and A-ring reduction. Metabolites retaining the 3-oxo-4-ene structure can be hydroxylated at position 6beta- as well as at an unidentified position, probably 16alpha-. Saturated steroids can be hydroxylated at positions 1beta-, 6alpha-, 15alpha- and 16alpha. A pair of hydroxy-20-dihydro-corticosterone metabolites (OH-DHB) were the most important excretory products accounting for about 40% of the total. One metabolite of this type was identified as 6beta-hydroxy-DHB; the other, of similar quantitative importance was probably 16alpha-hydroxy-DHB. The ratio of metabolites of corticosterone (B) to those of 11-dehydro-corticosterone (A) was greater than 9:1, considerably higher than that for the equivalent "human" ratio of 1:1 for cortisol to cortisone metabolites. Results from this study allowed the evaluation of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) activity in mice with deleted glucose-6-phosphate transporter (G6PT). These mice had attenuated back-conversion of A to B resulting in an increased ratio of A-metabolites to B-metabolites [Walker EA, Ahmed A, Lavery GG, Tomlinson JW, Kim SY, Cooper MS, Stewart PM, 11beta-Hydroxysteroid dehydrogenase type 1 regulation by intracellular glucose-6-phosphate, provides evidence for a novel link between glucose metabolism and HPA axis function. J Biol Chem 2007;282:27030-6]. We believe this study is currently the most comprehensive on the urinary steroid metabolic profile of the mouse. Quantitatively less steroid is excreted in urine than in feces by this species but urine analysis is more straightforward and the hepatic metabolites are less subject to microbial degradation than if feces was analyzed.

The relationship of chronic fatigue to psychiatric illness in community, primary care and tertiary care samples

This paper reviews the psychiatric disorders associated with the symptom of fatigue in community, primary care and tertiary care samples. In each of these subsamples, studies using structured psychiatric interviews and operational diagnostic criteria are compared and contrasted. In summary, in community, primary care and tertiary care populations, there was a high association between the symptom of fatigue and affective and anxiety disorders. The prevalence rates of affective illness went up linearly in patients with fatigue as one moved from community to primary care and tertiary populations. The fact that fatigue is a common symptom in the community and is associated with significantly higher medical utilization when associated with affective and anxiety disorders may explain the increased association between this symptom and affective illness in primary and tertiary care.

Corticosteroids, 11beta-hydroxysteroid dehydrogenase isozymes and the rabbit choroid plexus

The epithelial cells of the choroid plexus (CP) are responsible for cerebrospinal fluid (CSF) secretion into the ventricles of the brain. The balance between CSF production and drainage, in part, facilitates a normal intracranial pressure. The secretion of Na(+) and anions by the CP creates an osmotic gradient driving water into the ventricles. This is opposite to classical Na(+) transporting tissues, such as the kidney, where Na(+) and water reabsorption is mediated by 11beta-hydroxysteroid dehydrogenase type 2 that protects the mineralocorticoid receptor by abrogating active cortisol to inactive cortisone. In the human ocular ciliary epithelium, Na(+) and water secretion is dependent on a novel mediator of ciliary epithelial Na(+) transport, 11beta-HSD type 1 (11beta-HSD1), that generates intraocular cortisol. In a mechanism analogous to that of the embryologically related ocular ciliary epithelium, we propose that autocrine regulation of intracranial cortisol is dependent on 11beta-HSD1 expression in the CP epithelial cells. By conducting immunolocalisation studies on brains from New Zealand White Albino rabbits, we defined the expression of 11beta-HSD1 in the secretory CP epithelial cells. Enzyme assays performed on intact rabbit CP whole tissue explants confirmed predominant 11beta-HSD1 activity, generating cortisol that was inhibited by glycyrrhetinic acid (an 11beta-HSD inhibitor). Using the real time-polymerase chain reaction, rabbit CP tissue was found to express levels of 11beta-HSD1, glucocorticoid receptor alpha and serum and glucocorticoid-regulated kinase 1 mRNA comparable to that expressed in rabbit ocular ciliary body, thereby highlighting the similarity between these two tissues. Furthermore, an enzyme-linked immunosorbent assay of rabbit CSF revealed a median cortisol concentration of 1.7 nmol/l (range 1.4-4.3 nmol/l, n = 9). Our data have identified a functional 11beta-HSD1 within the CP, mediating intracranial cortisol bioavailability. Expression of 11beta-HSD1 may be fundamental in the regulation of CSF secretion and the local generation of cortisol may represent a pathophysiological mechanism underlying cortisol-dependent neuroendocrine diseases.

In vivo pharmacological resultant analysis reveals noncompetitive interactions between opioid antagonists in the rat tail-withdrawal assay

BACKGROUND AND PURPOSE

Pharmacological resultant analysis is a technique that can detect secondary effects of competitive antagonists in vitro. The utility of pharmacological resultant analysis as a potential tool for the investigation of antagonist interactions in vivo was examined in the present study using two opioid antagonists, naltrexone and CTAP.

EXPERIMENTAL APPROACH

Using the experimental design of pharmacological resultant analysis, the well-characterized opioid antagonist naltrexone was examined in the presence of multiple doses of CTAP to block the antinociceptive effects of morphine in the rat warm-water (55(o)C), tail-withdrawal assay.

KEY RESULTS

Alone, all doses of naltrexone, CTAP, and CTOP examined blocked the antinociceptive effects of morphine. In the presence of fixed doses of 1 or 10 microg CTAP, increasing doses of naltrexone produced dose-dependent shifts to the right in the morphine dose-response curve. However, a lower dose of naltrexone in combination with 1 or 10 mug CTAP failed to alter the morphine dose-response curve. In the presence of a fixed dose of 0.1 mg kg(-1) naltrexone, CTAP doses produced irregular shifts to the right in the morphine dose-response curves.

CONCLUSIONS AND IMPLICATIONS

Resultant analysis was applied and an apparent pK(C) value for CTAP was found to be one log unit higher than the apparent pA(2) value for CTAP, evidence that CTAP may have secondary actions or that a signal transducer function may be altered by the combinations of these antagonists. Taken together, these data suggest pharmacological resultant analysis can reveal novel interactions between antagonists in vivo.

Molecular basis for the apparent mineralocorticoid excess syndrome in the Oman population

11beta-Hydroxysteroid dehydrogenase type 2 (11beta-HSD2) plays a crucial role in converting hormonally active cortisol to inactive cortisone, thereby conferring specificity upon the mineralocorticoid receptor (MR). Mutations in the gene encoding 11beta-HSD2 (HSD11B2) account for an inherited form of hypertension, the syndrome of "Apparent Mineralocorticoid Excess" (AME) where cortisol induces hypertension and hypokalaemia. We report five different mutations in the HSD11B2 gene in four families from Oman with a total of 9 affected children suffering from AME. Sequence data demonstrate the previously described L114Delta6nt mutation in exon 2 and new mutations in exon 3 (A221V), exon 5 (V322ins9nt) and for the first time in exon 1 (R74G and P75Delta1nt) of the HSD11B2 gene. These additional mutations provide further insight into AME and the function of the 11beta-HSD2 enzyme. The prevalence of monogenic forms of hypertension such as AME remains uncertain. However, our data suggests AME may be a relevant cause of hypertension in certain ethnic groups, such as the Oman population.

Characterization of human trophoblast as a mineralocorticoid target tissue

In mineralocorticoid target tissues, 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) confers mineralocorticoid receptor selectivity by metabolizing hormonally active cortisol to inactive cortisone, allowing aldosterone access to the receptor. This enzyme is also expressed in high abundance in fetal tissues, particularly in placental trophoblast, where a role has been proposed in regulating fetal growth and development by protecting the fetus from maternal hypercortisolaemia and modulating local glucocorticoid receptor (GR), rather than mineralocorticoid receptor-mediated responses. As such the placenta has not been considered a mineralocorticoid target tissue. We have used conventional RT-PCR and real-time quantitative RT-PCR to demonstrate that primary cultures of term human cytotrophoblast express the mineralocorticoid-responsive genes Na/K-ATPase (alpha1 and beta1 subunits), epithelial sodium channel (ENaC, alpha and gamma subunits) and the serum and glucocorticoid-inducible kinase (SGK). SGK expression was found to be rapidly and strongly induced by corticosteroids (24- and 38-fold by 10(-7) mol/l aldosterone and 10(-7) mol/l dexamethasone respectively after 1 h). Dexamethasone-, but not aldosterone-stimulated SGK induction was inhibited by GR antagonist (RU38486), confirming the presence of a functional mineralocorticoid receptor and suggesting that placental trophoblast expresses a functional mineralocorticoid receptor, which is in part responsible for the corticosteroid regulation of SGK expression. Placental 11beta-HSD2 may protect the MR in a fashion analogous to classical mineralocorticoid tissues to modulate trophoblast sodium transport.

Inhibition of 11beta-hydroxysteroid dehydrogenase type 1 lowers intraocular pressure in patients with ocular hypertension

BACKGROUND

Intraocular pressure (IOP) is maintained by a balance between aqueous humour (AH) production (dependent on sodium transport across a ciliary epithelial bi-layer) and drainage (predominantly through the trabecular meshwork). In peripheral epithelial tissues, sodium and water transport is regulated by corticosteroids and the 11beta-hydroxysteroid dehydrogenase (11beta-HSD) isozymes (11beta-HSD1 activating cortisol from cortisone, 11beta-HSD2 inactivating cortisol to cortisone).

AIM

To analyse expression of 11beta-HSD in the human eye and investigate its putative role in AH formation.

DESIGN

Multipart prospective study, including a randomized controlled clinical trial.

METHODS

The expression of 11beta-HSD1 in normal human anterior segments was evaluated by in situ hybridization (ISH). RT-PCR for 11beta-HSDs, glucocorticoid and mineralocorticoid receptors (GR, MR) was performed on human ciliary body tissue. AH cortisol and cortisone concentrations were measured by radioimmunoassay on specimens taken from patients with primary open-angle glaucoma (POAG) and age-matched controls. Randomized, placebo-controlled studies of healthy volunteers and patients with ocular hypertension (OHT, raised IOP but no optic neuropathy) assessed the effect of oral carbenoxolone (CBX, an inhibitor of 11beta-HSD) on IOP.

RESULTS

ISH defined expression of 11beta-HSD1 in the ciliary epithelium, while RT-PCR analysis of ciliary body tissue confirmed expression of 11beta-HSD1, with additional GR and MR, but not 11beta-HSD2 expression. In both POAG patients and controls, AH concentrations of cortisol exceeded those of cortisone. The CBX-treated healthy volunteers who demonstrated the largest change in urinary cortisol metabolites, indicative of 11beta-HSD1 inhibition, had the greatest fall in IOP. Patients with OHT showed an overall reduction of IOP by 10% following CBX administration, compared to baseline (p<0.0001).

DISCUSSION

CBX lowers IOP in patients with ocular hypertension. Our data suggest that this is mediated through inhibition of 11beta-HSD1 in the ciliary epithelium. Selective and topical inhibitors of 11beta-HSD1 could provide a novel treatment for patients with glaucoma.

Association studies between microsatellite markers within the gene encoding human 11beta-hydroxysteroid dehydrogenase type 1 and body mass index, waist to hip ratio, and glucocorticoid metabolism

Two isozymes of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) interconvert active cortisol (F) and inactive cortisone (E). 11beta-HSD1 is an oxo-reductase (E to F) expressed in several glucocorticoid target tissues, including liver and adipose tissue, where it facilitates glucocorticoid-induced gluconeogenesis and adipocyte differentiation, respectively. We have isolated a full-length HSD11B1 genomic clone; the gene is more than 30 kb in length, not 9 kb in length as previously reported, principally due to a large intron 4. Two polymorphic (CA)(n) repeats have been characterized within intron 4: a CA(19) repeat 2.7 kb 3' of exon 4 and a CA(15) repeat 3 kb 5' of exon 5. The microsatellites, CA(19) and CA(15), were PCR amplified using fluorescent primers and were genotyped on an ABI 377 DNA sequencer from DNA of 413 normal individuals enrolled in the MONICA study of cardiovascular risk factors and 557 Danish men (ADIGEN study), of whom 234 were obese [body mass index (BMI), >/=31 kg/m(2) ] at draft board examination and 323 were randomly selected controls from the draftee population with BMI below 31 kg/m(2) (mean +/- SE, 21.7 +/- 0.41). Genotypic data from the normal MONICA cohort was compared with gender, 5beta-tetrahydrocortisol+5alpha-tetrahydrocortisol/tetrahydrocortisone ratio, and waist to hip (W:H) ratio. When analyzed by allele length (0, 1, or 2 short alleles) for the CA(19) marker, there was a trend toward a higher 5beta-tetrahydrocortisol+5alpha-tetrahydrocortisol/tetrahydrocortisone ratio (P = 0.058) and an increased W:H ratio (2 vs. 0.1 short; P(c) = 0.10) with overrepresentation of short alleles. The opposite was true for the CA(15) locus, with longer alleles at this locus predicting increased 11beta-HSD1 activity, particularly in females. Genotypic data from the ADIGEN case-control population was compared with clinical markers of obesity such as BMI and W:H ratio. There was no significant difference in the distribution of either microsatellite marker between lean and obese groups. Allele distributions were binomial, as seen for the MONICA cohort, and the data were split accordingly (zero, one, or two short alleles). No significant association was seen between grouped alleles and the clinical parameters. No association was observed between HSD11B1 genotype and BMI in either population. These data suggest that 11beta-HSD1 is not a major factor in explaining genetic susceptibility to obesity per se. However, weak associations between HSD11B1 genotype, increased 11beta-HSD1 activity, and W:H ratio suggest that polymorphic variability at the HSD11B1 locus may influence susceptibility to central obesity through enhanced 11beta-HSD1 activity (E to F conversion) in visceral adipose tissue.

Cost-effectiveness of a collaborative care program for primary care patients with persistent depression

OBJECTIVE

The authors evaluated the incremental cost-effectiveness of stepped collaborative care for patients with persistent depressive symptoms after usual primary care management.

METHOD

Primary care patients initiating antidepressant treatment completed a standardized telephone assessment 6-8 weeks after the initial prescription. Those with persistent major depression or significant subthreshold depressive symptoms were randomly assigned to continued usual care or collaborative care. The collaborative care included systematic patient education, an initial visit with a consulting psychiatrist, 2-4 months of shared care by the psychiatrist and primary care physician, and monitoring of follow-up visits and adherence to medication regimen. Clinical outcomes were assessed through blinded telephone assessments at 1, 3, and 6 months. Health services utilization and costs were assessed through health plan claims and accounting data.

RESULTS

Patients receiving collaborative care experienced a mean of 16.7 additional depression-free days over 6 months. The mean incremental cost of depression treatment in this program was $357. The additional cost was attributable to greater expenditures for antidepressant prescriptions and outpatient visits. No offsetting decrease in use of other health services was observed. The incremental cost-effectiveness was $21.44 per depression-free day.

CONCLUSIONS

A stepped collaborative care program for depressed primary care patients led to substantial increases in treatment effectiveness and moderate increases in costs. These findings are consistent with those of other randomized trials. Improving outcomes of depression treatment in primary care requires investment of additional resources, but the return on this investment is comparable to that of many other widely accepted medical interventions.

Expression and putative role of 11 beta-hydroxysteroid dehydrogenase isozymes within the human eye

PURPOSE

The human eye is an important target tissue for steroid hormones, and glucocorticoids have been implicated in the pathogenesis of ocular disease, including glaucoma. In peripheral tissues, corticosteroid hormone action is regulated at a prereceptor level through the activity of the 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) isozymes: an oxo-reductase (11 beta-HSD1) that activates cortisol (F) from cortisone (E) and a dehydrogenase (11 beta-HSD2) that inactivates F to E. The purpose of this study was to analyze the expression and putative role of 11 beta-HSD within the human eye.

METHODS

Immunohistochemical and reverse transcription-polymerase chain reaction (RT-PCR) studies were performed on sections of human ocular tissues, surgical trabecular meshwork (TM) specimens and a ciliary nonpigmented epithelial (NPE) cell-line. Free F and E concentrations in aqueous humor were determined by gas chromatography-mass spectrometry (GC/MS). IOP was measured in eight male volunteers before and after oral ingestion of carbenoxolone (CBX), a known inhibitor of 11 beta-HSD.

RESULTS

11 beta-HSD1 was expressed in the basal cells of the corneal epithelium and the NPE. 11 beta-HSD2 was restricted to the corneal endothelium. RT-PCR revealed mRNA for only the glucocorticoid receptor (GR) in the TM specimens, whereas GR, mineralocorticoid receptor and 11 beta-HSD1 mRNAs were all present in the NPE cell line. The demonstration of free F in excess of E (F/E 14:1) in the aqueous humor suggested predominant 11 beta-HSD1 activity. Compared with baseline (14.7 +/- 1.06 mm Hg, mean +/- SD), the IOP decreased significantly on both the third and seventh days of CBX ingestion (12.48 +/- 1.11 mm Hg, P < 0.0001 and 11.78 +/- 1.50 mm Hg, P < 0.0001, respectively).

CONCLUSIONS

These results suggest that the 11 beta-HSD1 isozyme may modulate steroid-regulated sodium transport across the NPE, thereby influencing IOP.

Functional expression, characterization, and purification of the catalytic domain of human 11-beta -hydroxysteroid dehydrogenase type 1

11-beta-hydroxysteroid dehydrogenase type 1 catalyzes the conversion of cortisone to hormonally active cortisol and has been implicated in the pathogenesis of a number of disorders including insulin resistance and obesity. The enzyme is a glycosylated membrane-bound protein that has proved difficult to purify in an active state. Extracted enzyme typically loses the reductase properties seen in intact cells and shows principally dehydrogenase activity. The C-terminal catalytic domain is known to contain a disulfide bond and is located within the lumen of the endoplasmic reticulum, anchored to the membrane by a single N-terminal transmembrane domain. We report here the functional expression of the catalytic domain of the human enzyme, without the transmembrane domain and the extreme N terminus, in Escherichia coli. Moderate levels of soluble active protein were obtained using an N-terminal fusion with thioredoxin and a 6xHis tag. In contrast, the inclusion of a 6xHis tag at the C terminus adversely affected protein solubility and activity. However, the highest levels of active protein were obtained using a construct expressing the untagged catalytic domain. Nonreducing electrophoresis revealed the presence of both monomeric and dimeric disulfide bonded forms; however, mutation of a nonconserved cysteine residue resulted in a recombinant protein with no intermolecular disulfide bonds but full enzymatic activity. Using the optimal combination of plasmid construct and E. coli host strain, the recombinant protein was purified to apparent homogeneity by single step affinity chromatography. The purified protein possessed both dehydrogenase and reductase activities with a K(m) of 1.4 micrometer for cortisol and 9.5 micrometer for cortisone. This study indicates that glycosylation, the N-terminal region including the transmembrane helix, and intermolecular disulfide bonds are not essential for enzyme activity and that expression in bacteria can provide active recombinant protein for future structural and functional studies.

Three-choice discrimination in pigeons is based on relative efficacy differences among opioids

RATIONALE

Drug discrimination assays can provide important information on receptor selectivity and relative efficacy to guide the classification and characterization of opioid agonists.

OBJECTIVES

A three-choice discrimination was established among high efficacy opioid agonist morphine, low efficacy opioid agonist nalbuphine, and saline to examine the conditions under which differences in relative efficacy might serve as a basis for stimulus control.

METHODS

Seven White Carneau pigeons were trained to discriminate among 5.6 mg/kg nalbuphine, 3.2 mg/kg morphine, and saline under fixed ratio 30 (FR30) schedules of food reinforcement. Substitution and antagonism experiments were then conducted with mu, kappa, and delta opioids and naltrexone, respectively and the percent responding appropriate to the training stimuli was determined.

RESULTS

Low, intermediate, and high doses of morphine produced > or = 80% saline-, > or = 60% nalbuphine-, and > or = 96% morphine-appropriate responding, respectively. Low and high doses of nalbuphine produced > or = 80% saline- and nalbuphine-appropriate responding, respectively. In substitution tests, low doses of fentanyl and etorphine produced partial nalbuphine-appropriate responding (20-60%) and high doses produced > or = 60-80% morphine-appropriate responding. Intermediate doses of buprenorphine and dezocine produced > or = 60-80% nalbuphine-appropriate responding and high doses produced > or = 80% morphine-appropriate responding. The lower efficacy agonists butorphanol, nalorphine, and levallorphan produced > or = 40-80% nalbuphine-appropriate responding. The kappa agonists spiradoline and U50,488 produced approximately > or = 50% nalbuphine-appropriate responding whereas d-amphetamine, saline, and delta agonists BW373U86 and SNC 80 produced > or = 80% saline-appropriate responding. Naltrexone produced > or = 80% saline-appropriate responding and reversed the stimulus effects of morphine and nalbuphine.

CONCLUSIONS

The discrimination between morphine and nalbuphine in pigeons is predominantly based on the relative efficacy differences between morphine, a higher-efficacy mu agonist and nalbuphine, a lower-efficacy mu agonist.

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.

Expression of 11 beta-hydroxysteroid dehydrogenase isozymes and corticosteroid hormone receptors in primary cultures of human trophoblast and placental bed biopsies

Interconversion of active and inactive glucocorticoids, e.g. cortisol (F) and cortisone (E) is catalysed by 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) which exists as two isoforms. We have used human placental bed biopsies and an in-vitro cytotrophoblast cell culture system to examine the expression and activity of the 11 beta-HSD isoforms along with that of the glucocorticoid and mineralocorticoid receptors (GR and MR). Immunohistochemistry localized 11 beta-HSD1 to decidualized stromal cells and 11 beta-HSD2 to villous cytotrophoblast, syncytiotrophoblasts and trophoblast cells invading the placental bed and maternal vasculature. In primary cultures of human cytotrophoblast, 11 beta-HSD2, GR and MR mRNA were expressed. Low levels of 11 beta-HSD1 mRNA were noted in these cultured cells, but could be explained on the basis of contaminating, vimentin-positive decidual stromal cells (< or =5%). Enzyme activity studies confirmed the presence of a high-affinity, NAD-dependent dehydrogenase activity (K(m) 137 nmol/l and V(max) 128 pmol E/h/mg protein), indicative of the 11 beta-HSD2 isoform. No reductase activity was observed. The presence of functional MR and GR was determined using Scatchard analyses of dexamethasone and aldosterone binding (MR K(d) 1.4 nmol/l B(max) 3.0; GR K(d) 6.6 nmol/l B(max) 16.2 fmol/ng protein). The expression of 11 beta-HSD1 in maternal decidua and 11 beta-HSD2 in adjacent trophoblast suggests an important role for glucocorticoids in determining trophoblast invasion. The presence of the MR within trophoblast indicates that some of the effects of cortisol could be MR- rather than GR-mediated.

Depression and self-reported physical health in patients with coronary disease: mediating and moderating factors

OBJECTIVES

The purpose of this study was to define how the relation between depression and self-reported physical health in patients with coronary disease is modified by other patient-centered factors.

METHODS

We conducted a prospective cohort study of 111 patients (members of a health maintenance organization) with angiographically documented coronary disease, examining factors (physical symptoms, psychological states and traits, and spousal support) modifying the relation between depression and patient-reported physical health 5 years later using multiple hierarchical regression models.

RESULTS

Five regression models (all including demographic and disease severity covariates) were constructed to predict physical health from depression only (R2 = 0.22); depression plus angina and fatigue (R2 = 0.53); depression plus positive affect and novelty seeking and their interaction (R2 = 0.48); depression plus spousal support (R2 = 0.27); and depression, angina, fatigue, positive affect, and novelty seeking (overall model) (R2 = 0.65). Depression remained significant in each model, but the proportion of variance it predicted was diminished in the presence of the other variables (bivariate r = 0.39, partial r = 0.37-0.13).

CONCLUSIONS

The effect of depression on self-reported physical health is significantly mediated by physical symptoms (angina and fatigue), personality states and traits (positive affect and novelty seeking), and spousal support. Positive affect and novelty seeking had more marked effects on physical health in the presence of more depression. Thus, a broad range of factors beyond the severity of coronary disease itself affect the perceived physical health of patients with coronary heart disease.

Differential tolerance to antinociceptive effects of mu opioids during repeated treatment with etonitazene, morphine, or buprenorphine in rats

RATIONALE

Repeated treatment experiments with high and low efficacy agonists provide critical insight into possible mechanisms underlying development of opioid tolerance.

OBJECTIVE

Experiments in a tail-withdrawal assay tested the hypothesis that magnitude of tolerance to antinociceptive effects is inversely related to agonist relative efficacy in rats intermittently treated with etonitazene. morphine, or buprenorphine.

METHODS

The antinociceptive effects of five mu opioid agonists were tested in male, Sprague-Dawley rats in a warm-water tail-withdrawal assay. To induce tolerance, escalating doses of the higher efficacy agonist etonitazene, the high efficacy agonist morphine, or the lower efficacy agonist buprenorphine were administered twice daily for 2-8 weeks.

RESULTS

Etonitazene, etorphine, morphine, buprenorphine, and GPA 1657 [(1)-beta-2'-hydroxy-2,9-dimethyl-5-phenyl-6,7-benzomorphan] produced dose-dependent increases in tail-withdrawal latency until 100% maximum possible effect (%MPE) was obtained. Treatment with escalating doses of etonitazene, morphine, or buprenorphine produced greater tolerance to the lower efficacy agonists buprenorphine and GPA 1657 than to the higher efficacy agonists etonitazene, etorphine, and morphine. Treatment with buprenorphine, a lower efficacy agonist, produced greater tolerance than did treatment with equivalent doses of the higher efficacy agonists morphine or etonitazene.

CONCLUSIONS

Taken together, these data suggest that magnitude of antinociceptive tolerance is inversely related to relative efficacy of mu agonists, with lower efficacy agonists being more susceptible to tolerance than are higher efficacy agonists under these intermittent dosing conditions.

Dissemination of diabetes care guidelines: lessons learned from community health centers

PURPOSE

This study was conducted to evaluate the impact of a provider problem-based learning (PBL) intervention on screening for complications of diabetes in community health centers.

METHODS

A successive sampling design was used to compare selected standards of diabetes care delivered preintervention with the care delivered postintervention at 2 community health centers and 1 comparison centers. Two randomly assigned intervention sites received a PBL intervention focused on care guidelines for prevention of diabetes complications, with telephone follow-up over 12 months. Effects of the intervention were determined from an audit of 200 charts from each site.

RESULTS

The odds of having a glycosylated hemoglobin test more than doubled from preintervention to postintervention, and the odds of having a foot examination more than tripled across centers. Measurement of creatinine and glycosylated hemoglobin were associated; the odds of having one test tripled when the other had been measured. Rates for documentation of patient education were significantly lower at the intervention site where free patient education booklets were distributed.

CONCLUSIONS

Improvements in diabetes care were not consistent among community health centers. Interventions involving system and policy changes may be more effective in implementing and sustaining improvements than just provider education.

The patient-provider relationship: attachment theory and adherence to treatment in diabetes

OBJECTIVE

Lack of adherence to diabetic self-management regimens is associated with a high risk of diabetes complications. Previous research has shown that the quality of the patient-provider relationship is associated with adherence to diabetes treatment. This study attempts to improve understanding of both patient and provider factors involved in lack of adherence to treatment in diabetic patients by using the conceptual model of attachment theory.

METHOD

Instruments that assessed attachment, treatment adherence, depression, diabetes severity, patient-provider communication, and demographic data were administered to 367 patients with type 1 and 2 diabetes in a health maintenance organization primary care setting. Glucose control, medical comorbidity, and adherence to medications and clinic appointments were determined from automated data. Analyses of covariance were used to determine if attachment style and quality of patient-provider communication were associated with adherence to treatment.

RESULTS

Patients who exhibited dismissing attachment had significantly worse glucose control than patients with preoccupied or secure attachment. An interaction between attachment and communication quality was significantly associated with glycosylated hemoglobin (Hb A(1c)) levels. Among the patients with a dismissing attachment style, there was a significant difference in glycosylated hemoglobin levels between those who rated their patient-provider communication as poor (mean=8.50%, SD=1.55%) and those who rated this communication as good (mean=7.49%, SD=1. 33%). Among all patients who were taking oral hypoglycemics, adherence to medications and glucose monitoring was significantly worse in patients who exhibited dismissing attachment and rated their patient-provider communication as poor.

CONCLUSIONS

Dismissing attachment in the setting of poor patient-provider communication is associated with poorer treatment adherence in patients with diabetes.

Predictors of outcome in a primary care depression trial

OBJECTIVE

Previous treatment trials have found that approximately one third of depressed patients have persistent symptoms. We examined whether depression severity, comorbid psychiatric illness, and personality factors might play a role in this lack of response.

DESIGN

Randomized trial of a stepped collaborative care intervention versus usual care.

SETTING

HMO in Seattle, Wash.

PATIENTS

Patients with major depression were stratified into severe (N = 149) and mild to moderate depression (N = 79) groups prior to randomization.

INTERVENTIONS

A multifaceted intervention targeting patient, physician, and process of care, using collaborative management by a psychiatrist and primary care physician.

MEASUREMENTS AND MAIN RESULTS

Patients with more severe depression had a higher risk for panic disorder (odds ratio [OR], 5.8), loneliness (OR, 2.6), and childhood emotional abuse (OR, 2.1). Among those with less severe depression, intervention patients showed significantly improved depression outcomes over time compared with those in usual care (z = -3.06, P<.002); however, this difference was not present in the more severely depressed groups (z = 0.61, NS). Although the group with severe depression showed differences between the intervention and control groups from baseline to 3 months that were similar to the group with less severe depression (during the acute phase of the intervention), these differences disappeared by 6 months.

CONCLUSIONS

Initial depression severity, comorbid panic disorder, and other psychosocial vulnerabilities were associated with a decreased response to the collaborative care intervention. Although the intervention was appropriate for patients with moderate depression, individuals with higher levels of depression may require a longer continuation phase of therapy in order to achieve optimal depression outcomes.

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.

How diabetes specialists treat their own diabetes: findings from a study of the AADE and ADA membership

PURPOSE

The purpose of this study was to determine how diabetes specialists, who themselves have diabetes, manage their own care.

METHODS

An independent research organization faxed anonymous, 1-page surveys to all professional members of the American Association of Diabetes Educators (AADE) and the American Diabetes Association (ADA) who had valid fax numbers. Only those individuals with diabetes were asked to fill out and return the survey.

RESULTS

Of the 12,525 surveys that were distributed, 802 (6.4%) were returned. The prevalence of type 1 diabetes in this sample was estimated to be 13 times higher than in the general US population, whereas the prevalence of type 2 diabetes was 42% to 54% lower. Of the respondents with type 1 diabetes, most (96%) practiced intensive treatment regimens, and more than half used an insulin infusion pump.

CONCLUSIONS

Diabetes specialists treat their own diabetes according to current standards of medical care, with insulin pumps being the preferred method of insulin therapy for type 1 diabetes in this sample. Knowing that experts almost universally practice intensive treatment regimens may be a powerful motivator for patients and sends a strong message to primary care providers and payers regarding the need for treating diabetes according to current standards of care.

Low-intensity treatment of depression in primary care: is it problematic?

The aim of this study was to examine patterns of care and outcomes of depressed patients under primary care during acute phase treatment. A cohort of depressed patients was assessed 6-8 weeks after starting pharmacotherapy in four large primary care clinics in a health maintenance organization. These patients (n = 1671) were receiving antidepressant treatment for a new episode of depression. To calculate main outcome measures, Structured Clinical Interview for Depression evaluated prior history and current depression status. Visit and pharmacy refill data described use of health services and antidepressant medication. Six to eight weeks after starting antidepressant therapy, 33.2% of patients had 0-3 depressive symptoms and no prior history of depression, an additional 42.3% also reported 0-3 symptoms but were at high risk of relapse, and 24. 5% were persistently depressed with 4 or more depressive symptoms. In the initial 6 weeks of treatment, these three groups showed similar use of antidepressant medication and health services. About 50% in each group had no follow-up visit for depression and 32%-42% had not refilled their antidepressant prescription. In general, depressed patients under primary care obtained low-intensity pharmacotherapy and inconsistent follow-up visits during initial acute phase treatment. Six weeks after starting antidepressant medicine, many were still symptomatic or recovered but had a high risk of depression relapse. Patients with unfavorable outcomes did not receive more intensive management than the one-third who had favorable outcomes.

Discriminative stimulus effects of two doses of fentanyl in rats: pharmacological selectivity and effect of training dose on agonist and antagonist effects of mu opioids

RATIONALE

Discriminative stimulus effects of mu opioids vary systematically as a function of training dose. Differences among training doses may arise from multiple mechanisms.

OBJECTIVES

In vivo apparent pA(2) analyses were used to examine the contributions of opioid mechanisms to stimulus control by low and high training doses of the mu opioid fentanyl.

METHODS

Saline and one of two doses of fentanyl, administered s.c., were established as discriminative stimuli in two groups of rats (low training dose group: 0.01 mg/kg; high training dose group: 0.04 mg/kg). Generalization tests and in vivo apparent pA(2) analyses were used to evaluate receptor mechanisms of stimulus control.

RESULTS

Fentanyl, etonitazene, methadone, and morphine evoked full fentanyl generalization in both groups but were more potent in the low-dose group. Spiradoline and d-amphetamine did not evoke generalization in either group. Naltrexone antagonized stimulus and rate-altering effects of fentanyl in both groups, with apparent pA(2) values of 7. 6 in the low-dose group and 7.5 in the high-dose group. Nalbuphine and nalorphine evoked full generalization in the low-dose group but less than 40% generalization in the high-dose group. In the high-dose group, nalbuphine and nalorphine antagonized the stimulus and rate-altering effects of fentanyl with apparent pA(2) values of 5.3 and 6.1, respectively, demonstrating lower efficacy mu actions.

CONCLUSIONS

Changes in fentanyl training dose preserved the mu opioid selectivity of stimulus control but altered the intensity of the transduced mu opioid stimulus required for generalization. These differences in intensity of the fentanyl stimulus determined whether low efficacy mu opioids would evoke or antagonize fentanyl generalization.

Cellular responses of embryonic hyaline cartilage to experimental wounding in vitro

It is well established that the reparative potential of many tissues is greatest during embryonic development. Despite the extensive literature documenting repair in nonembryonic cartilage models, there is no comparable wealth of experience relating to embryonic cartilage repair. With the embryonic chick sternum as a model of hyaline cartilage, this paper accounts cellular responses and alterations in extracellular matrix composition in response to experimental wounding in vitro. Creation of an experimental lesion induced a rapid (<20 minutes) apoptotic response in chondrocytes adjacent to the lesion edge; the presence of perichondrium delayed this response. Alterations in the extracellular matrix included immediate mechanical damage to type-II collagen fibrils and an increase in the expression of chondroitin-4 sulphate next to the lesion. Creation of the lesion induced an increased proliferative response in chondrocytes behind the zone of apoptosis and the expression of alpha5 and alpha6 integrin subunits.

The effect of health education on the rate of ophthalmic examinations among African Americans with diabetes mellitus

OBJECTIVES

This study evaluated a multicomponent educational intervention to increase ophthalmic examination rates among African Americans with diabetes.

METHODS

A randomized trial was conducted with 280 African Americans with diabetes, enrolled from outpatient departments of 5 medical centers in the New York City metropolitan area, who had not had a dilated retinal examination within 14 months of randomization (65.7% female, mean age = 54.7 years [SD = 12.8 years]).

RESULTS

After site differences were controlled, the odds ratio for receiving a retinal examination associated with the intervention was 4.3 (95% confidence interval = 2.4, 7.8). The examination rate pooled across sites was 54.7% in the intervention group and 27.3% in the control group.

CONCLUSIONS

The intervention was associated with a rate of ophthalmic examination double the rate achieved with routine medical care.

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.

Characteristics of the adult learner

PURPOSE

This article provides an overview of adult learner characteristics, with an emphasis on those characteristics studied in diabetes patient education research.

METHODS

A selected review of the conceptual and research literature on general adult education and adult learning was conducted, with particular attention to diabetes patient education studies.

RESULTS

Characteristics reviewed included learning styles, literacy level, age/aging, ethnicity or culture, gender, and knowledge. Studies of the learning style of group vs individual education indicated some positive benefits for group learning; questions remain about optimal size or periodicity. Studies evaluating the benefits of culturally specific interventions for diabetes management have yielded some information. Characteristics related to gender and age have been studied, but often in pilot or feasibility studies without the power to answer the study questions.

CONCLUSIONS

There continue to be many gaps in knowledge related to adult learner characteristics in diabetes education. Lessons from both general adult learning literature and patient education literature from other chronic diseases should be evaluated and incorporated. The complexities of these learner characteristics create challenges in designing studies. However, evidence to support the need for effective educational interventions is of great importance for implementing change in health care.

Discriminative stimulus effects of nalbuphine in nontreated and morphine-treated pigeons

In the present study, the stimulus effects of the low efficacy agonist nalbuphine were examined under two conditions: nontreated and morphine treated. In the first experiment, five pigeons were trained to discriminate among 3.2 mg/kg morphine, 5.6 mg/kg nalbuphine, and saline. Nalbuphine produced nalbuphine-like responding. Low doses of morphine produced nalbuphine-like responding, whereas high doses produced morphine-like responding. Naltrexone produced saline-like responding and reversed the stimulus effects produced by the training doses of morphine and nalbuphine. Five different pigeons were treated daily with 10 mg/kg morphine (i.m.) and trained 6 h later to discriminate among 10 mg/kg morphine, 1.0 mg/kg nalbuphine and saline. In these pigeons, morphine produced morphine-like responding and nalbuphine produced nalbuphine-like responding. Morphine abstinence produced nalbuphine-like responding that was reversed by morphine. Additionally, naltrexone produced nalbuphine-like responding. These data suggest that the discrimination between morphine and nalbuphine in the nontreated and morphine-treated pigeons may be based on the relative efficacy differences between morphine, a higher efficacy mu-agonist, and nalbuphine a lower efficacy mu-agonist.

Adult health status of women with histories of childhood abuse and neglect

PURPOSE

Several recent studies have found associations between childhood maltreatment and adverse adult health outcomes. However, methodologic problems with accurate case determination, appropriate sample selection, and predominant focus on sexual abuse have limited the generalizability of these findings.

SUBJECTS AND METHODS

We administered a survey to 1,225 women who were randomly selected from the membership of a large, staff model health maintenance organization in Seattle, Washington. We compared women with and without histories of childhood maltreatment experiences with respect to differences in physical health status, functional disability, numbers and types of self-reported health risk behaviors, common physical symptoms, and physician-coded ICD-9 diagnoses.

RESULTS

A history of childhood maltreatment was significantly associated with several adverse physical health outcomes. Maltreatment status was associated with perceived poorer overall health (ES = 0.31), greater physical (ES = 0.23) and emotional (ES = 0.37) functional disability, increased numbers of distressing physical symptoms (ES = 0.52), and a greater number of health risk behaviors (ES = 0.34). Women with multiple types of maltreatment showed the greatest health decrements for both self-reported symptoms (r = 0.31) and physician coded diagnoses (r = 0.12).

CONCLUSIONS

Women with childhood maltreatment have a wide range of adverse physical health outcomes.

Costs of health care use by women HMO members with a history of childhood abuse and neglect

BACKGROUND

Early childhood maltreatment has been associated with adverse adult health outcomes, but little is known about the magnitude of adult health care use and costs that accompany maltreatment. We examined differences in annual health care use and costs in women with and without histories of childhood sexual, emotional, or physical abuse or neglect.

METHODS

A random sample of 1225 women members of a health maintenance organization completed a 22-page questionnaire inquiring into childhood maltreatment experiences as measured by the Childhood Trauma Questionnaire. Health care costs and use data were obtained from the automated cost-accounting system of the health maintenance organization, including total costs, outpatient and primary care costs, and emergency department visits.

RESULTS

Women who reported any abuse or neglect had median annual health care costs that were $97 (95% confidence interval, $0.47-$188.26) greater than women who did not report maltreatment. Women who reported sexual abuse had median annual health care costs that were $245 (95% confidence interval, $132.32-$381.93) greater than costs among women who did not report abuse. Women with sexual abuse histories had significantly higher primary care and outpatient costs and more frequent emergency department visits than women without these histories.

CONCLUSION

Although the absolute cost differences per year per woman were relatively modest, the large number of women in the population with these experiences suggests that the total costs to society are substantial.

Vascular surgical society of great britain and ireland: Re-evaluation of criteria for reoperation in carotid endarterectomy using intraoperative duplex imaging

BACKGROUND: The aim of this study was to compare data obtained during surgery with data collected at 6 weeks after operation to evaluate appropriate criteria for reoperation. METHODS: One hundred and twenty consecutive patients undergoing carotid endarterectomy had duplex scans at operation and 6 weeks later. Neurological evaluation was also documented. RESULTS: Of 96 patients who had a normal intraoperative duplex scan by standard criteria, 91 had normal scans at 6 weeks. One occluded an internal carotid artery (ICA) at 6 weeks with no symptoms. Four had kinks or high-grade contralateral lesions leading to velocity enhancement but no filling defect. All were asymptomatic. Twenty-four patients had abnormal intraoperative scans. Thirteen patients had visible kinking of the ICA or reperfusion hyperaemia; 12 of these patients had normal 6-week scans and one had a mild residual kink but no symptoms. Eleven patients had visible colour-filling defects and significant velocity enhancement. Nine of these were reopened and refashioned. Subsequent duplex imaging was satisfactory in all cases and 6-week scans were normal. One patient had an occluded ICA at operation and developed a dense stroke after operation. Another had residual raised velocities distally which remained at 6 weeks. This patient had no symptoms. CONCLUSION: Intraoperative velocity measurements alone cannot be relied upon as an indication for reoperation. Significant velocity enhancement combined with a visible filling defect appears to represent a satisfactory criterion for reoperation. There were no complications as a result of reoperation. There was no early restenosis in the whole group and there were no neurological sequelae in any patient with a satisfactory scan using the above criteria.

Assessing the ethical costs and benefits of trauma-focused research

Although scientists and members of Institutional Review Boards must balance the needs of investigators and participants in research, virtually no evidence is available to inform this decision making. This study examines the frequency and correlates of adverse reactions and adequacy of informed consent among 1174 women in an HMO who completed a trauma-focused health survey, and a subset of 252 women who later completed a trauma-focused research interview. Despite the sensitive content, the majority of women participants found participation in the interview and the questionnaire study to be a positive experience. Although a small number of women, particularly those with a history of maltreatment, underestimated the level of upset they would subsequently experience, the majority still did not regret participating, indicating that informed consent procedures were adequate, with a large proportion reporting immediate perceptions of personal gain. Finally, the cost-benefit ratio appears stable 48 hours post-interview, with some minor fluctuations. Overall, these results suggest that research on childhood victimization is well tolerated by women who participate. Though a small number of women may be disturbed by these investigations, in general, adverse reactions appear less common than previously anticipated.

Naltrexone and beta-funaltrexamine antagonism of the antinociceptive and response rate-decreasing effects of morphine, dezocine, and d-propoxyphene

RATIONALE

Patterns of competitive and insurmountable antagonism provide important data to guide the classification and characterization of different types of opioid agonists as well as infer the mechanism of action for agonists.

OBJECTIVE

Experiments with the competitive antagonist, naltrexone, and the insurmountable antagonist, beta-funaltrexamine (beta-FNA), were conducted to determine whether the antinociceptive and rate-decreasing effects of the opioid agonists dezocine and d-propoxyphene are 1) mediated through muu opioid receptors in rats, and 2) differ from morphine with respect to relative efficacy.

METHODS

The rat tail-withdrawal assay was used to measure antinociception and a fixed ratio 20 (FR20) schedule of food delivery was used to measure rate suppression.

RESULTS

Naltrexone (0.01-1.0 mg/kg) was approximately equipotent as an antagonist of the antinociceptive and rate-decreasing effects of both morphine and dezocine and as an antagonist of the antinociceptive effects of d-propoxyphene. Naltrexone failed to block the rate-decreasing effects of d-propoxyphene. beta-FNA (5 and 10 mg/kg) also antagonized the antinociceptive and rate-decreasing effects of morphine and dezocine as well as the antinociceptive effects of d-propoxyphene. beta-FNA failed to produce a dose-dependent antagonism of the rate-decreasing effects of d-propoxyphene.

CONCLUSIONS

These data suggest that the antinociceptive effects of morphine, dezocine, and d-propoxyphene and the rate-decreasing effects of morphine and dezocine are mediated through mu opioid receptors. Overall, high doses of beta-FNA produced a greater degree of antagonism of the behavioral effects of dezocine than morphine or d-propoxyphene, confirming other reports that dezocine is a lower efficacy agonist than morphine. Additionally, the degree of antagonism produced by beta-FNA was greater for the antinociceptive effects of all three compounds than for the rate-decreasing effects.

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.

Can enhanced acute-phase treatment of depression improve long-term outcomes? A report of randomized trials in primary care

OBJECTIVE

The authors' goal was to determine whether improved outcomes from enhanced acute-phase (3-month) treatment for depression in primary care persisted.

METHOD

They conducted a 19-month follow-up assessment of 156 patients with major depression in the Collaborative Care intervention trials, which had found greater improvements in treatment adherence and depressive symptoms at 4 and 7 months for patients given enhanced acute-phase treatment than for patients given routine treatment in a primary care setting. Sixty-three of the 116 patients who completed the follow-up assessment had received enhanced treatment, and 53 had received routine treatment in primary care. The Inventory for Depressive Symptomatology and the Hopkins Symptom Checklist were used to measure depressive symptoms. Automated pharmacy data and self-reports were used to assess adherence to and adequacy of pharmacotherapy.

RESULTS

At 19 months, the patients who had received enhanced acute-phase treatment did not differ from those who had received routine primary care treatment in clinical outcomes or quality of pharmacotherapy.

CONCLUSIONS

Even though enhanced acute-phase treatment of depression in primary care resulted in better treatment adherence and better clinical outcomes at 4 and 7 months, these improvements failed to persist over the following year. Continued enhancement of depression treatment may be needed to ensure better long-term results.

Detection and treatment of depressive syndromes in a rural island clinic

BACKGROUND

Major depression is a serious and often persistent problem for 5 to 10 percent of patients in primary care. The detection and treatment of depression can be a particular challenge in rural settings. This study describes patterns of care for depression at a rural primary care clinic on an island off the coast of Washington State.

METHODS

For a period of 2 months, 226 primary care patients were evaluated for depression using a two-stage screening method. Structured chart abstraction was conducted for patients meeting criteria for major depression or dysthymia.

RESULTS

Ten percent of the study sample met Diagnostic and Statistical Manual of Medical Disorders, fourth edition, criteria for major depression, 4 percent met criteria for dysthymia, and 8 percent met criteria for major depression and dysthymia. Of the patients who had a diagnosis of major depression or dysthymia by the PRIME-MD, approximately 50 percent had their condition detected by their primary care provider, and approximately 50 percent received guideline level antidepressant treatment. Less than 40 percent of patients whose depression was treated with antidepressants made more than two visits during the 8 weeks after the initial prescription.

CONCLUSIONS

These findings are consistent with those from other primary care settings and suggest that there are many opportunities for improving the quality of care for depressed patients in rural primary care settings.

Medically unexplained symptoms in primary care

Fourteen common physical symptoms are responsible for almost half of all primary care visits. Only about 10% to 15% of these symptoms are found to be caused by an organic illness over a 1-year period. Patients with medically unexplained symptoms are frequently frustrating to primary care physicians and utilize medical visits and costs disproportionately. This paper will review the relationship between psychological distress and the decision to seek medical care for common physical symptoms such as fatigue and headache. Evidence will be presented demonstrating that an increasing number of medically unexplained symptoms over a patient's lifetime correlate linearly with the number of anxiety and depressive disorders experienced, the score on the personality dimension of neuroticism, and the degree of functional impairment. Several scales measuring somatization and hypochondriasis are recommended for primary care and medical specialty patients.

Relapse of depression in primary care. Rate and clinical predictors

OBJECTIVE

To determine the clinical predictors and rate of relapse for major depression in primary care.

DESIGN

A cohort study of subjects in 2 randomized trials of depressed patients diagnosed and prescribed antidepressant medicine by primary care physicians. Baseline, 7-month, and 19-month assessments were conducted.

SETTING

A large primary care clinic of a staff-model health maintenance organization.

PATIENTS

Two hundred fifty-one primary care patients who did not satisfy Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (DSM-III-R) criteria for major depression at 7 months.

MAIN OUTCOME MEASURES

Relapse was defined as (1) satisfying DSM-III-R criteria for major depression at 19 months, or (2) reporting an interval episode of 2 weeks or more of depressed mood and symptoms between 7 and 19 months. Predictors examined included demographic characteristics, medical comorbidity, disability, and psychological symptoms. Depressive symptoms were measured by Inventory of Depressive Symptoms and Hopkins Symptoms Checklist.

RESULTS

Of the patients, 37.1% reported relapse of depression in the 12-month relapse-risk period. The 2 major risk factors associated with relapse were (1) persistence of subthreshold depressive symptoms 7 months after the initiation of antidepressant therapy (odds ratio, 3.3; 95% confidence interval, 2.74-3.93) and (2) history of 2 or more episodes of major depression, or chronic mood symptoms for 2 years (odds ratio, 2.1; 95% confidence interval, 1.41-2.76). Patients with both risk factors were approximately 3 times more likely to relapse than patients with neither.

CONCLUSIONS

The relapse rate among primary care patients treated for depression approached that of specialty samples, with more than one third reporting relapse in 1 year. Clinical characteristics can help target high-risk patients for relapse prevention efforts.

Understanding and caring for the distressed patient with multiple medically unexplained symptoms

BACKGROUND

Although physicians commonly encounter patients with complicated medical problems, some have a mix of unexplained medical symptoms and distress that can seem overwhelming to patient and physician alike.

METHODS

We describe a model for thinking about and helping these complex patients. The model was developed from our personal clinical experience as primary care psychiatric consultants, as well as from a review of the literature using such key words as "difficult," "frustrating," and "somatization."

RESULTS

The model involves understanding predisposing factors that render the patient vulnerable to the development of a disabling condition, precipitating factors that initiate an episode of illness, and perpetuating factors that maintain maladaptive illness behaviors with time.

CONCLUSIONS

Awareness of these factors allows the clinician not only to tolerate and gradually unravel the complicated interactions that create and sustain distress in patients with multiple medically unexplained symptoms, but also devise practical and effective management strategies for these complex patients.

Clocinnamox antagonism of the antinociceptive effects of mu opioids in squirrel monkeys

The opioid agonists morphine, etorphine, buprenorphine and U50,488 were examined alone and in combination with the insurmountable opioid antagonist clocinnamox (C-CAM) in squirrel monkeys responding under a schedule of shock titration. In this procedure, shock intensity increased every 15 sec from 0.01 to 2.0 mA in 30 increments. Five lever presses during any given 15-sec shock period produced a 15-sec timeout, after which shock resumed at the next lower intensity. When given alone, each of these agonists increased the median intensity at which the monkeys maintained shock [median shock level (MSL)]. At the highest dose examined alone, each agonist produced maximal increases in MSL and, except buprenorphine, decreased response rates. C-CAM dose-dependently antagonized the effects of morphine, etorphine and buprenorphine on MSL. In the presence of the higher C-CAM doses, etorphine, morphine and buprenorphine did not produce maximal effects on MSL. The effects of U50,488 were not systematically altered when tested in combination with the highest C-CAM dose. In general, C-CAM was more potent and the duration of antagonism was slightly longer against buprenorphine than against morphine and etorphine. Quantitative analysis of these data according to an extended model of yielded the following apparent affinity and efficacy estimates, respectively: etorphine (0. 085 mg/kg, 117); morphine (49 mg/kg, 24) and buprenorphine (0.62 mg/kg, 7.1). Determination of the individual q values over time indicated that the receptor population recovers more quickly after C-CAM antagonism of etorphine than from C-CAM antagonism of either morphine or buprenorphine. These data suggest that C-CAM functions as a long-lasting antagonist of mu opioid agonist actions in a shock titration procedure and yields estimates of relative intrinsic efficacy with the rank order of etorphine > morphine > buprenorphine.