Early calcium and cardiac contraction defects in a model of phospholamban R9C mutation in zebrafish

The phospholamban mutation Arg 9 to Cys (R9C) has been found to cause a dilated cardiomyopathy in humans and in transgenic mice, with ventricular dilation and premature death. Emerging evidence suggests that phospholamban R9C is a loss-of-function mutation with dominant negative effect on SERCA2a activity. We imaged calcium and cardiac contraction simultaneously in 3 and 9 days-post-fertilization (dpf) zebrafish larvae expressing plnb^R9C in the heart to unveil the early pathological pathway that triggers the disease. We generated transgenic zebrafish lines expressing phospholamban wild-type (Tg(myl7:plnb^wt)) and phospholamban R9C (Tg(myl7:plnb^R9C)) in the heart of zebrafish. To measure calcium and cardiac contraction in 3 and 9 dpf larvae, Tg(myl7:plnb^wt) and Tg(myl7:plnb^R9C) fish were outcrossed with a transgenic line expressing the ratiometric fluorescent calcium biosensor mCyRFP1-GCaMP6f. We found that Plnb^R9C raised calcium transient amplitude, induced positive inotropy and lusitropy, and blunted the β-adrenergic response to isoproterenol in 3 dpf larvae. These effects can be attributed to enhanced SERCA2a activity induced by the Plnb^R9C mutation. In contrast, Tg(myl7:plnb^R9C) larvae at 9 dpf exhibited ventricular dilation, systolic dysfunction and negative lusitropy, hallmarks of a dilated cardiomyopathy in humans. Importantly, N-acetyl-L-cysteine rescued this deleterious phenotype, suggesting that reactive oxygen species contribute to the pathological pathway. These results also imply that dysregulation of calcium homeostasis during embryo development contributes to the disease progression at later stages. Our in vivo model in zebrafish allows characterization of pathophysiological mechanisms leading to heart disease, and can be used for screening of potential therapeutical agents.

Phenotyping calcium and contraction in a zebrafish model of phospholamban R9C mutation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science, Innovation and Universities, Spain by Consejería de Educación, Cultura y Deportes. Junta de Comunidades de Castilla-La Mancha.

Background

Phospholamban regulates SERCA2a pump activity by reducing its calcium affinity in the heart. Under β-adrenergic stimulation, protein kinase A (PKA) phosphorylates phospholamban attenuating its inhibitory effect on SERCA2a. The phospholamban mutation Arg 9 to Cys (R9C) was firstly identified in an American family with ventricular dilatation and premature death, and subsequently in a cohort of dilated cardiomyopathy patients in South Africa. Emerging evidence suggests that phospholamban R9C is a loss-of-function mutation with autosomal dominant inheritance. In vitro studies revealed that it enhances pentamer assembly by disulfide bridge formation, reducing the availability of phospholamban monomers to regulate SERCA2a.

Purpose

The present study aimed to investigate defects in Ca2+ handling and cardiac function of phospholamban R9C mutation in an in vivo zebrafish model.

Methods

We generated transgenic zebrafish lines overexpressing phospholamban wild-type (TgPLNwt) and phospholamban R9C (TgPLNR9C) in the heart of zebrafish. To measure calcium kinetics in 3 day-old larvae, TgPLNwt and TgPLNR9C fish were outcrossed with transgenic zebrafish lines expressing the fluorescent calcium biosensor mCyRFP1-GCaMP6f (TgRFP-GcaMP6f) and the bioluminescence calcium biosensor GFP-Aequorin (TgGA) in the heart.

Results

Overexpression of phospholamban wild-type and R9C did not alter the heart rate compared to sibling larvae, and no differences were observed in the upstroke and recovery time of the calcium transients.  However, atrial and ventricular calcium transient amplitude were higher in TgPLNR9C larvae with respect to TgPLNwt larvae. Contractile force of the heart, assessed as the fractional shortening, increased in TgPLNR9C larvae compared to siblings and TgPLNwt. Furthermore, stroke volume and cardiac output were also higher in TgPLNR9C larvae. Bioluminescence experiments were performed to estimate the average calcium levels in the heart. We found that TgPLNR9C larvae showed higher calcium levels than sibling and TgPLNwt larvae. To evaluate the responsiveness to β-adrenergic stimulation, larvae were treated with the β-agonist isoproterenol. Calcium transient amplitude and contractile force increased in sibling and TgPLNwt larvae after treatment. However, this response was absent in TgPLNR9C larvae, suggesting that they were hyper-stimulated in basal conditions, displaying amplitude and contractile force similar to sibling and TgPLNwt larvae treated with isoproterenol.

Conclusion

TgPLNR9C larvae exhibited aberrant calcium handling in the heart with higher calcium levels and contractility, consistent with a lack of inhibition of SERCA2a. Consequently, TgPLNR9C larvae did not respond to β-adrenergic stimulation. These results were consistent with previous in vitro studies carried out in cardiomyocites infected with phospholamban R9C and highlighted the pathological defects of phospholamban R9C at early stages of the disease.

Modeling Human Cardiac Arrhythmias: Insights from Zebrafish

Cardiac arrhythmia, or irregular heart rhythm, is associated with morbidity and mortality and is described as one of the most important future public health challenges. Therefore, developing new models of cardiac arrhythmia is critical for understanding disease mechanisms, determining genetic underpinnings, and developing new therapeutic strategies. In the last few decades, the zebrafish has emerged as an attractive model to reproduce in vivo human cardiac pathologies, including arrhythmias. Here, we highlight the contribution of zebrafish to the field and discuss the available cardiac arrhythmia models. Further, we outline techniques to assess potential heart rhythm defects in larval and adult zebrafish. As genetic tools in zebrafish continue to bloom, this model will be crucial for functional genomics studies and to develop personalized anti-arrhythmic therapies.

Cardioluminescence in Transgenic Zebrafish Larvae: A Calcium Imaging Tool to Study Drug Effects and Pathological Modeling

Zebrafish embryos and larvae have emerged as an excellent model in cardiovascular research and are amenable to live imaging with genetically encoded biosensors to study cardiac cell behaviours, including calcium dynamics. To monitor calcium ion levels in three to five days post-fertilization larvae, we have used bioluminescence. We generated a transgenic line expressing GFP-aequorin in the heart, Tg(myl7:GA), and optimized a reconstitution protocol to boost aequorin luminescence. The analogue diacetylh-coelenterazine enhanced light output and signal-to-noise ratio. With this cardioluminescence model, we imaged the time-averaged calcium levels and beat-to-beat calcium oscillations continuously for hours. As a proof-of-concept of the transgenic line, changes in ventricular calcium levels were observed by Bay K8644, an L-type calcium channel activator and with the blocker nifedipine. The β-adrenergic blocker propranolol decreased calcium levels, heart rate, stroke volume, and cardiac output, suggesting that larvae have a basal adrenergic tone. Zebrafish larvae treated with terfenadine for 24 h have been proposed as a model of heart failure. Tg(myl7:GA) larvae treated with terfenadine showed bradycardia, 2:1 atrioventricular block, decreased time-averaged ventricular calcium levels but increased calcium transient amplitude, and reduced cardiac output. As alterations of calcium signalling are involved in the pathogenesis of heart failure and arrhythmia, the GFP-aequorin transgenic line provides a powerful platform for understanding calcium dynamics.

Hhex regulates the specification and growth of the hepatopancreatic ductal system

Significant efforts have advanced our understanding of foregut-derived organ development; however, little is known about the molecular mechanisms that underlie the formation of the hepatopancreatic ductal (HPD) system. Here, we report a role for the homeodomain transcription factor Hhex in directing HPD progenitor specification in zebrafish. Loss of Hhex function results in impaired HPD system formation. We found that Hhex specifies a distinct population of HPD progenitors that gives rise to the cystic duct, common bile duct, and extra-pancreatic duct. Since hhex is not uniquely expressed in the HPD region but is also expressed in endothelial cells and the yolk syncytial layer (YSL), we tested the role of blood vessels as well as the YSL in HPD formation. We found that blood vessels are required for HPD patterning, but not for HPD progenitor specification. In addition, we found that Hhex is required in both the endoderm and the YSL for HPD development. Our results shed light on the mechanisms directing endodermal progenitors towards the HPD fate and emphasize the tissue specific requirement of Hhex during development.

Loss of the Mia40a oxidoreductase leads to hepato-pancreatic insufficiency in zebrafish

Development and function of tissues and organs are powered by the activity of mitochondria. In humans, inherited genetic mutations that lead to progressive mitochondrial pathology often manifest during infancy and can lead to death, reflecting the indispensable nature of mitochondrial biogenesis and function. Here, we describe a zebrafish mutant for the gene mia40a (chchd4a), the life-essential homologue of the evolutionarily conserved Mia40 oxidoreductase which drives the biogenesis of cysteine-rich mitochondrial proteins. We report that mia40a mutant animals undergo progressive cellular respiration defects and develop enlarged mitochondria in skeletal muscles before their ultimate death at the larval stage. We generated a deep transcriptomic and proteomic resource that allowed us to identify abnormalities in the development and physiology of endodermal organs, in particular the liver and pancreas. We identify the acinar cells of the exocrine pancreas to be severely affected by mutations in the MIA pathway. Our data contribute to a better understanding of the molecular, cellular and organismal effects of mitochondrial deficiency, important for the accurate diagnosis and future treatment strategies of mitochondrial diseases.

Mitochondrial pathologies which result from mutations in the nuclear DNA remain incurable and often lead to death. As mitochondria play various roles in cellular and tissue-specific contexts, the symptoms of mitochondrial pathologies can differ between patients. Thus, diagnosis and treatment of mitochondrial disorders remain challenging. To enhance this, the generation of new models that explore and define the consequences of mitochondria insufficiencies is of central importance. Here, we present a mia40a zebrafish mutant as a model for mitochondrial dysfunction, caused by an imbalance in mitochondrial protein biogenesis. This mutant shares characteristics with existing reports on mitochondria dysfunction, and has led us to identify novel phenotypes such as enlarged mitochondrial clusters in skeletal muscles. In addition, our transcriptomics and proteomics data contribute important findings to the existing knowledge on how faulty mitochondria impinge on vertebrate development in molecular, tissue and organ specific contexts.

Pitx2c orchestrates embryonic axis extension via mesendodermal cell migration

Pitx2c, a homeodomain transcription factor, is classically known for its left-right patterning role. However, an early wave of pitx2 expression occurs at the onset of gastrulation in several species, indicating a possible earlier role that remains relatively unexplored. Here we show that in zebrafish, maternal-zygotic (MZ) pitx2c mutants exhibit a shortened body axis indicative of convergence and extension (CE) defects. Live imaging reveals that MZpitx2c mutants display less persistent mesendodermal migration during late stages of gastrulation. Transplant data indicate that Pitx2c functions cell non-autonomously to regulate this cell behavior by modulating cell shape and protrusive activity. Using transcriptomic analyses and candidate gene approaches, we identify transcriptional changes in components of the chemokine-ECM-integrin dependent mesendodermal migration network. Together, our results define pathways downstream of Pitx2c that are required during early embryogenesis and reveal novel functions for Pitx2c as a regulator of morphogenesis.

The Hippo pathway effector Wwtr1 regulates cardiac wall maturation in zebrafish

Cardiac trabeculation is a highly regulated process that starts with the delamination of compact layer cardiomyocytes. The Hippo signaling pathway has been implicated in cardiac development but many questions remain. We have investigated the role of Wwtr1, a nuclear effector of the Hippo pathway, in zebrafish and find that its loss leads to reduced cardiac trabeculation. However, in mosaic animals, wwtr1^-/- cardiomyocytes contribute more frequently than wwtr1^+/- cardiomyocytes to the trabecular layer of wild-type hearts. To investigate this paradox, we examined the myocardial wall at early stages and found that compact layer cardiomyocytes in wwtr1^-/- hearts exhibit disorganized cortical actin structure and abnormal cell-cell junctions. Accordingly, wild-type cardiomyocytes in mosaic mutant hearts contribute less frequently to the trabecular layer than when present in mosaic wild-type hearts, indicating that wwtr1^-/- hearts are not able to support trabeculation. We also found that Nrg/Erbb2 signaling, which is required for trabeculation, could promote Wwtr1 nuclear export in cardiomyocytes. Altogether, these data suggest that Wwtr1 establishes the compact wall architecture necessary for trabeculation, and that Nrg/Erbb2 signaling negatively regulates its nuclear localization and therefore its activity.

Claudins are essential for cell shape changes and convergent extension movements during neural tube closure

During neural tube closure, regulated changes at the level of individual cells are translated into large-scale morphogenetic movements to facilitate conversion of the flat neural plate into a closed tube. Throughout this process, the integrity of the neural epithelium is maintained via cell interactions through intercellular junctions, including apical tight junctions. Members of the claudin family of tight junction proteins regulate paracellular permeability, apical-basal cell polarity and link the tight junction to the actin cytoskeleton. Here, we show that claudins are essential for neural tube closure: the simultaneous removal of Cldn3, −4 and −8 from tight junctions caused folate-resistant open neural tube defects. Their removal did not affect cell type differentiation, neural ectoderm patterning nor overall apical-basal polarity. However, apical accumulation of Vangl2, RhoA, and pMLC were reduced, and Par3 and Cdc42 were mislocalized at the apical cell surface. Our data showed that claudins act upstream of planar cell polarity and RhoA/ROCK signaling to regulate cell intercalation and actin-myosin contraction, which are required for convergent extension and apical constriction during neural tube closure, respectively.

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Simultaneous removal of Cldn3, −4 and −8 causes open neural tube defects.

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Folic acid cannot rescue open NTDs caused by depletion of Cldn3, −4 and −8.

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Removal of Cldn3, −4 and −8 prevents convergent extension.

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Apical constriction to form the median hinge point requires Cldn3, −4 and −8.

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Claudins localize polarity complex components to the apical surface.

Organ Function as a Modulator of Organ Formation: Lessons from Zebrafish

Organogenesis requires an intricate balance between cell differentiation and tissue growth to generate a complex and fully functional organ. However, organogenesis is not solely driven by genetic inputs, as the development of several organ systems requires their own functionality. This theme is particularly evident in the developing heart as progression of cardiac development is accompanied by increased and altered hemodynamic forces. In the absence or disruption of these forces, heart development is abnormal, suggesting that the heart must sense these changes and respond appropriately. Here, we discuss concepts of how embryonic heart function contributes to heart development using lessons learned mostly from studies in zebrafish.

Are there conserved roles for the extracellular matrix, cilia, and junctional complexes in left-right patterning?

Many different types of molecules have essential roles in patterning the left-right axis and directing asymmetric morphogenesis. In particular, the relationship between signaling molecules and transcription factors has been explored extensively. Another group of proteins implicated in left-right patterning are components of the extracellular matrix, apical junctions, and cilia. These structural molecules have the potential to participate in the conversion of morphogenetic cues from the extracellular environment into morphogenetic patterning via their interactions with the actin cytoskeleton. Although it has been relatively easy to temporally position these proteins within the hierarchy of the left-right patterning pathway, it has been more difficult to define how they mechanistically fit into these pathways. Consequently, our understanding of how these factors impart patterning information to influence the establishment of the left-right axis remains limited. In this review, we will discuss those structural molecules that have been implicated in early phases of left-right axis development.

Claudin family members exhibit unique temporal and spatial expression boundaries in the chick embryo

The claudin family of proteins are integral components of tight junctions and are responsible for determining the ion specificity and permeability of paracellular transport within epithelial and endothelial cell layers. Several members of the claudin family have been shown to be important during embryonic development and morphogenesis. However, detailed embryonic expression patterns have been described for only a few claudins. Here, we provide a phylogenetic analysis of the chicken claudins and a comprehensive analysis of their mRNA expression profiles. We found that claudin family members exhibit both overlapping and unique expression patterns throughout development. Especially striking were the distinct expression boundaries observed between neural and non-neural ectoderm, as well as within ectodermal derivatives. Claudins were also expressed in endodermally-derived tissues, including the anterior intestinal portal, pharynx, lung and pancreas and in mesodermally derived tissues such as the kidney, gonad and heart. The overlapping zones of claudin expression observed in the chick embryo may confer distinct domains of ion permeability within the early epiblast and in epithelial, mesodermal and endothelial derivatives that may ultimately influence embryonic patterning and morphogenesis during development.

Claudin-5 expression in the vasculature of the developing chick embryo

The claudin family of proteins are integral components of tight junctions and are responsible for determining the ion specificity and permeability of paracellular transport within epithelial and endothelial cell layers. Studies in human, mouse, Xenopus, and zebrafish have shown that only a limited number of claudins are expressed in endothelial cells. Here, we report the expression pattern of Claudin-5 during chick development. Between HH stage 4 and 6 Claudin-5 expression was observed exclusively in extraembryonic tissue. Claudin-5 expression was not observed in the embryo until HH stage 8, coincident with the onset of embryonic vascularization. Claudin-5 expression was maintained in the developing vasculature in the embryonic and extraembryonic tissue throughout organogenesis (HH stage 19-35), including the vasculature of the ectoderm and of organs derived from the mesoderm and endoderm lineages. These data describe a conserved expression pattern for Claudin-5 in the endothelial tight junction barrier and is the first report of the onset of Claudin-5 expression in a vertebrate embryo.

Manipulating claudin expression in avian embryos

Since the discovery of Claudin-1 and -2 by Tsukita and colleagues in the late 1990s [Furuse et al. J Cell Biol 141:1539-50,1998], claudin family members have been found to have critical roles in maintaining the integrity of epithelial and endothelial tight junctions [Furuse and Moriwaki Ann N Y Acad Sci 1165:58-61, 2009; Morita et al. Proc Natl Acad Sci USA 96:511-6, 1999; Tsukita and Furuse Ann N Y Acad Sci 915:129-35, 2000; Turksen and Troy J Cell Sci 117:2435-47, 2004]. The properties of distinct claudin family members in tight junction permeability and specificity have been extensively studied in vitro using cell culture models. In vivo, claudin family members are dynamically regulated during embryogenesis and alterations in their expression patterns can have detrimental effects on the formation and physiological function of the tissues in which they are expressed. The chick embryo provides an excellent system to dissect the roles of specific family members in vivo and to explore the effects of modulating claudin expression during the epithelial-to-mesenchymal and mesenchymal-to-epithelial transitions that are associated with tissue morphogenesis and differentiation. We are using the chick embryo to understand the roles of the claudin family of tight junction proteins during gastrulation and left-right patterning during embryogenesis. Here, we describe methodologies for manipulating claudin gene expression in specific target tissues during chick embryogenesis.

Expression patterns of hormones, signaling molecules, and transcription factors during adenohypophysis development in the chick embryo

The chick embryo is an ideal model to study pituitary cell-type differentiation. Previous studies describing the temporal appearance of differentiated pituitary cell types in the chick embryo are contradictory. To resolve these controversies, we used RT-PCR to define the temporal onset and in situ hybridization and immunohistochemistry to define the spatial localization of hormone expression within the pituitary. RT-PCR detected low levels of Fshbeta (gonadotropes) and Pomc (corticotropes, melanotropes) mRNA at E4 and Gh (somatotropes), Prl (lactotropes), and Tshbeta (thyrotropes) mRNA at E8. For all hormones, sufficient accumulation of mRNA and/or protein to permit detection by in situ hybridization or immunohistochemistry was observed approximately 3 days later and in all cases corresponded to a notable increase in RT-PCR product. We also describe the expression patterns of signaling (Bmp2, Bmp4, Fgf8, Fgf10, Shh) and transcription factors (Pitx1, Pitx2, cLim3) known to be important for pituitary organogenesis in other model organisms.

Anxiety and depression symptoms in patients with diabetes

AIMS

To identify the prevalence and major determinants of anxiety and depression symptoms in patients with diabetes.

METHODS

A cross-sectional study of 2049 people with Types 1 and 2 diabetes, selected from patients experiencing three different models of care in Ireland: (i) traditional mixed care; (ii) hospital/general practitioner (GP) shared care; (iii) structured GP care. Anxiety and depression symptoms were assessed with the Hospital Anxiety and Depression Scale (HADS). Analyses were conducted primarily using logistic regression with adjustment for relevant confounders.

RESULTS

The overall response rate was 71% (n = 1456). Based on the HADS, there was evidence of high levels of anxiety and depression symptoms in patients with diabetes; 32.0% (95% confidence interval = 29.5-34.6%) exceeded the HADS cut-off score of 'mild to severe' anxiety and 22.4% (95% confidence interval = 20.2-24.7%) exceeded the HADS cut-off score of 'mild to severe' depression. Diabetes complications, smoking, uncertainty about glycaemic control and being an ex-drinker or a heavy drinker were risk factors for both higher anxiety and depression scores in multivariate analysis. Female gender and poor glycaemic control were risks factors associated only with higher anxiety scores. Higher socio-economic status and older age were protective factors for lower anxiety and depression scores. Type of diabetes, insulin use, marital status and models of care were not significant predictors of anxiety and depression scores.

CONCLUSIONS

The prevalence of anxiety and depression symptoms in patients with diabetes is considerably higher than in general population samples. These data serve as a benchmark for the prevalence of anxiety and depression symptoms in patients with diabetes.

Dietary patterns in middle-aged Irish men and women defined by cluster analysis

Objectives:

To identify and characterise dietary patterns in a middle-aged Irish population sample and study associations between these patterns, sociodemographic and anthropometric variables and major risk factors for cardiovascular disease.

Design:

A cross-sectional study.

Subjects and methods:

A group of 1473 men and women were sampled from 17 general practice lists in the South of Ireland. A total of 1018 attended for screening, with a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and provided a fasting blood sample for glucose, lipids and homocysteine. Dietary intake was assessed using a standard food-frequency questionnaire adapted for use in the Irish population. The food-frequency questionnaire was a modification of that used in the UK arm of the European Prospective Investigation into Cancer study, which was based on that used in the US Nurses' Health Study. Dietary patterns were assessed primarily by K-means cluster analysis, following initial principal components analysis to identify the seeds.

Results:

Three dietary patterns were identified. These clusters corresponded to a traditional Irish diet, a prudent diet and a diet characterised by high consumption of alcoholic drinks and convenience foods. Cluster 1 (Traditional Diet) had the highest intakes of saturated fat (SFA), monounsaturated fat (MUFA) and percentage of total energy from fat, and the lowest polyunsaturated fat (PUFA) intake and ratio of polyunsaturated to saturated fat (P:S). Cluster 2 (Prudent Diet) was characterised by significantly higher intakes of fibre, PUFA, P:S ratio and antioxidant vitamins (vitamins C and E), and lower intakes of total fat, MUFA, SFA and cholesterol. Cluster 3 (Alcohol & Convenience Foods) had the highest intakes of alcohol, protein, cholesterol, vitamin B12, vitamin B6, folate, iron, phosphorus, selenium and zinc, and the lowest intakes of PUFA, vitamin A and antioxidant vitamins (vitamins C and E). There were significant differences between clusters in gender distribution, smoking status, physical activity, body mass index, waist circumference and serum homocysteine concentrations.

Conclusion:

In this general population sample, cluster analysis methods yielded two major dietary patterns: prudent and traditional. The prudent dietary pattern is associated with other health-seeking behaviours. Study of dietary patterns will help elucidate links between diet and disease and contribute to the development of healthy eating guidelines for health promotion.

Environmental risk factors and gender in nasal polyposis

The aetiology of nasal polyps remains obscure. Although clinically associated with asthma, notably in women, there is a marked male preponderance of polyposis. This study aimed to explore environmental pollutant triggers and gender differences in risk factors for nasal polyps. In total, 900 patients having surgery for polyposis and 120 new patients with nasal polyps completed a questionnaire with regard to occupational dust and chemical exposure. The male to female ratio was 2:1, and 52% were smokers, although only 37% of women smoked compared with 66% of men. Exposure to occupational dusts and chemicals was noted in 45% (retrospective) and 53% (prospective) of respondents. Women were 1.6 times more likely to be asthmatic and 2.7 times more likely to have allergic rhinitis than men. Men were 2.25 times more likely to be smokers and 2.48 times more likely to have been exposed to chemicals and dusts than women (all statistically significant differences). No significant gender associations were found for hayfever, eczema, aspirin intolerance, alcohol intake or hobby dust exposure.

The Spanish National Institutes of Health-Chronic Prostatitis Symptom Index: translation and linguistic validation

PURPOSE

The prominence of health related quality of life end points in international clinical research underscores the importance of well validated and translated measures to enable cross-cultural comparison. The National Institutes of Health (NIH)-Chronic Prostatitis Symptom Index (CPSI) assesses symptoms and health related quality of life in men with chronic nonbacterial, NIH type III prostatitis. To expand its use to Spanish speaking patients we performed a translation and linguistic validation.

MATERIALS AND METHODS

The 9-item NIH-CPSI was translated into Spanish according to a standard methodology of 2 forward translations, 1 reconciled version, back translation of the reconciled version and 3 independent reviews by bilingual experts. The purpose of this methodology was to create a single universal Spanish version that would be acceptable to native Spanish speakers inside and outside of the United States. After the translation process the Spanish version was pre-tested in Argentina, Mexico, Spain and the United States. Patient responses were analyzed to identify necessary modifications. The internal consistency of the CPSI was evaluated using Cronbach's alpha. Pearson's product moment correlations were used to evaluate construct validity.

RESULTS

Data were collected from chronic prostatitis patients, including 15 in Argentina, 15 in Mexico, 4 in the United States and 3 in Spain. The translation had high reliability overall and in all subscales (Cronbach's coefficient alpha = 0.81 to 0.94), and the subscales correlated well with each other (r = 0.76 to 0.97). However, patients expressed difficulty in distinguishing the response categories "a menudo" ("often") from "normalmente" ("usually") in question 3. We revised "a menudo" to "muchas veces" ("much of the time") and "normalmente" to "casi siempre" ("almost always") to improve the distinctiveness of response categories.

CONCLUSIONS

The Spanish NIH-CPSI has high reliability as well as face and construct validity in Spanish speaking men from various countries. The Spanish NIH-CPSI permits cross-cultural comparisons of men with chronic nonbacterial prostatitis.

Risk factors for clinical benign prostatic hyperplasia in a community-based population of healthy aging men

We defined risk factors for a clinical diagnosis of benign prostatic hyperplasia (BPH) among subjects of the population-based Massachusetts Male Aging Study. In 1987-89 1709 men aged 40-70 provided baseline risk factor data and were followed for a mean of 9 years; 1019 men without prostate cancer provided follow-up data. We classified men with clinical BPH at follow-up if they reported (1) frequent or difficulty urinating and were told by a health professional that they had an enlarged or swollen prostate or (2) if they reported having surgery for BPH. At follow-up the prevalence of clinical BPH was 19.4%, increasing from 8.4% of men aged 38-49 years to 33.5% of men aged 60-70 years (P < 0.001 for trend). Elevated free PSA levels (age- and total PSA-adjusted OR, top vs. bottom quartile ng/mL 4.4, 95% CI 1.9-10.5), heart disease (age-adjusted OR 2.1, CI 1.3-3.3), and use of beta-blocker medications (OR 1.8, CI 1.1-3.0) increased odds for BPH, while current cigarette smoking (OR 0.5, CI 0.3-0.8) and high levels of physical activity (top vs. bottom quartile kcals/day OR 0.5, CI 0.3-0.9) decreased odds of BPH. All but the medication effects persisted in fully adjusted multivariable models. Total or fat calorie intake, sexual activity level, alcohol intake, body mass index, waist-hip ratio, diastolic blood pressure, a history of diabetes, hypertension, vasectomy, or serum levels of androgens or estrogens did not individually predict clinical BPH. We conclude that physical exercise and cigarette smoking appear to protect against development of clinical BPH. Elevated free PSA levels predict clinical BPH independent of total PSA levels. Risk associated with heart disease does not appear to be due solely to detection bias or to effects of heart disease medications. A wide variety of other characteristics appear to have no influence on risk for clinical BPH.

Rhizobium population dynamics in the pea rhizosphere of rhizobial inoculant strain applied in different formulations

The effect of inoculant formulation on the population dynamics of rhizobia in the pea rhizosphere was investigated using a streptomycin-resistant mutant of Rhizobium leguminosarum bv. viceae NITRAGIN128C56G (128C56G strR). The isolate was formulated into liquid, peat powder, and granular peat carriers, and was tested on pea at field sites near Saskatoon, Saskatchewan, and Beaverlodge, Alberta, in 1996 and 1997. The liquid and peat powder formulations were applied to seed while the granular inoculant was applied to soil. In three out of four site years, population dynamics were similar among formulations: an initial decline or lag period lasting 2-5 days followed by an increase to approximately 10(5) colony-forming units (CFU)/seedling by 14-28 days after planting (DAP) and, where sampled, a continuing increase from 10(7) to 10(8) CFU/plant at 63 DAP. In these same site years, nodule number (not determined at Beaverlodge in 1997) and nodule occupancy at 60 days were not significantly different among formulations. In contrast, soil populations of 128C56G strR from the liquid formulation declined to near zero by 28 DAP at Beaverlodge in 1996, when soil moisture was excessive in spring because of high rainfall. Populations increased in this treatment after this time, but remained significantly lower than the populations of the other two formulations throughout the sampling period. Pea seed yields were not significantly different among treatments in either year at Beaverlodge, but were significantly higher with granular inoculant than the noninoculated control in Saskatoon. Within inoculated treatments at Saskatoon, there were no significant differences in grain yield.

Dynamic assessment of imbalance in acoustic neuroma patients by sway magnetometry

INTRODUCTION: Imbalance may be a significant problem for patients with acoustic neuromas. Prospective data on patients with acoustic neuromas to establish how the vestibular system performs dynamically, in the perioperative phases, is not available. Posturography is an established method of measuring balance and sway magnetometry has been developed as a reliable technique in this field. AIMS: Prospectively to assess pre- and postoperative dynamic vestibular function in patients with acoustic neuromas using sway magnetometry. METHODS: Sway patterns were recorded on 12 patients with acoustic neuromas tested under two sets of conditions: first, a baseline test for 120 s, repeated after 120 s of vestibular stimulation. After each test a validated questionnaire to assess balance subjectively was compeleted: before operation and 1, 3 and 6 months after operation. RESULTS: (1) Patients with acoustic neuromas demonstrate 'overswing' on baseline testing: most exaggerated 1 month postoperatively. After vestibular stimulation the 'recovery' time was prolonged to 50 s postoperatively, 62 s postoperatively (1/12), 43 s (3/12), and 47 s (6/12) postoperatively. (2) Mean path length (normal range, 163-287 mm) was increased in all groups: preoperative = 332 mm, 1 month postoperatively = 358 mm, 3 months postoperatively = 308 and 6 months postoperatively = 343 mm (3) The Dizziness Handicap Inventory scores were elevated at all times of testing and significantly correlated with baseline path length (rs = 0.6, P = 0. 03) and vestibular stimulation path length (rs = 0.7, P = 0.01) preoperatively. CONCLUSIONS: This is the first dynamic, prospective study of balance in patients with acoustic neuromas. Abnormal sway patterns and prolonged recovery times pre- and postoperatively, most marked at 1 month, were demonstrated. A subjective assessment of balance disturbance reflected these abnormal sway measurements confirming its clinical usefulness.

The relative frequencies of HLA-DRB1*01 alleles in the major US populations

The frequencies of alleles in the HLA-DRB1*01 family were determined in each of five US populations from a database of 82,979 individuals. Individuals typed as DR1 (or DRB1*01) comprised between 7.6%-21.3% of the individuals in each population group. Fifty-nine DR1 individuals were randomly selected from each group and subjected to high-resolution DNA typing by polymerase chain reaction using sequence-specific oligonucleotide probes. DRB1*0101 was the most common allele in the Caucasian, Asian/Pacific Islander, and Native American groups while the DRB1*0102 allele was found in the majority of African Americans and Hispanics. DRB1*0103 was present at a similar frequency in all populations. DRB1*0104, DRB1*0105, and DRB1*0106 alleles were not observed.

Nutritional consequences of radiotherapy in early laryngeal carcinoma

In treating patients with malignant head and neck disease, radiotherapy may compromise their oral intake and, thus, their nutritional status. This study aimed to assess a subgroup of patients who received small field radiotherapy, where their early primary tumour itself would not be expected to affect swallowing and where significant nutritional problems are not traditionally identified. A retrospective analysis of hospital records was undertaken on 61 patients, treated for T1 and T2 N0 laryngeal squamous cell carcinoma with primary radical radiotherapy over a three year period (1993-1995 inclusive). At presentation, 97% had their weight and height recorded, enabling calculation of their body mass index (BMI); 13% presented with a BMI < 20 kg/m2 and the 26% of patients who complained of weight loss at presentation had a mean percentage weight loss of 5.35%. During treatment, 79% of patients had their weight recorded and 49% had a documented mean percentage weight loss of 6.4%. The mean BMI at the end of treatment was significantly lower than at presentation (P = 0.03). These effects occurred despite 80% of patients having at least one dietetic consultation (mean 3.5 consults), and 75% having received high protein/high calorie supplementation. The percentage weight loss during treatment correlated significantly with the gamma-glutamyl transpeptidase (gamma-GT) level at presentation. The biochemical markers, haemoglobin and albumin, were normal in the great majority at presentation and fell non-specifically during treatment in 82% and 56% of patients, respectively. We conclude that significant numbers of patients with early laryngeal malignancy are undernourished at presentation and, despite dietetic support, endure considerable nutritional problems during radiotherapy. Attention to nutritional issues is mandatory even in this group of patients previously considered to be less at risk because of the site and early stage of their disease.

Faculty training in general internal medicine: a survey of graduates from a research-intensive fellowship program

PURPOSE

To determine the fellowship experiences and career activities of the graduates of a research-intensive general internal medicine fellowship program.

METHOD

In 1997, the authors surveyed all graduates of the Harvard General Internal Medicine Fellowship Program, a research-intensive fellowship begun in 1979.

RESULTS

Of 105 surveys delivered to graduates, 103 (98%) were returned. During the fellowship, 82 graduates (80%) presented research findings at regional or national meetings, 89 (86%) published peer-reviewed articles based on their fellowship work, 75 (73%) precepted residents or medical students in the ambulatory setting, and 67 (65%) taught medical students in the preclinical years. At the time of the survey, 100 graduates (97%) held academic appointments: 48 as clinician-investigators, 23 as clinician-administrators, 15 as clinician-educators, and 15 as clinicians.

CONCLUSION

Graduates of this research-intensive fellowship pursued academic careers with research, teaching, administration, and clinical activities. Directors of similar fellowship programs should prepare their graduates for all these activities.

Parapharyngeal lipoma

Lipomas of the parapharyngeal space provide both a diagnostic and therapeutic challenge. They are extremely rare with only a few cases having been reported. We present the case of a right parapharyngeal space lipoma in a 69-year-old man that was excised via a transcervical approach.

Morphological assessment of the soft palate in habitual snoring using image analysis

OBJECTIVES

Define differences in palatal and uvular dimensions between habitual snorers and healthy nonsnoring control subjects. Document the changes in palatal configuration after different types of palatoplasty.

STUDY DESIGN

A prospective controlled clinical study was performed analyzing video recordings of the soft palate and oropharynx of 251 subjects (121 habitual snorers, 79 patients after laser-assisted uvulopalatoplasty ([LAUP], and 51 healthy volunteers).

METHODS

The recordings were captured using a rigid endoscope with a reference measure applied to the soft palate and a mark at the junction of the soft and hard palate. Four parameters were studied in the captured pictures after correction for the distortion deformity in fiberoptic endoscopic images: 1) length of soft palate, 2) length of uvula, 3) width of uvula, and 4) distance between posterior pillars.

RESULTS

Analysis showed that habitual snorers, compared with healthy volunteers have significantly increased soft palate length (P = .00001), increased uvula length (P = .0002) and width (P = .00001), and narrowed oropharyngeal isthmus (distance between the posterior pillars) (P = .04). In patients studied after LAUP, the length of the soft palate is significantly shorter (P = .00001) than in the preoperative cohort, and the oropharyngeal isthmus is significantly narrower (P = .00001). Moreover, this latter distance is significantly narrower (P = .00001) when compared with healthy volunteers.

CONCLUSIONS

Habitual snorers have a long soft palate, a long wide uvula, and a narrowed oropharyngeal isthmus. LAUP shortens and tightens the elongated palate and causes a further reduction in the space between the posterior pillars.

The subjective effects of smoking on nasal symptoms

One hundred and forty-four volunteers completed a validated questionnaire, to investigate the association between smoking, non-smoking and passive smoking status, and the degree of a range of 10 common nasal symptoms. Logistic regression showed that smokers were four times and passive smokers six times more likely to report hyposmia compared to non-smokers. No significant differences were found between the three groups for any of the other nine symptoms.

Distinguishing chronic prostatitis and benign prostatic hyperplasia symptoms: results of a national survey of physician visits

OBJECTIVES

The morbidity of chronic prostatitis results from a constellation of genitourinary symptoms. A recent study classified 21 of these symptoms into three categories: pain, voiding complaints, and sexual dysfunction. Pain symptoms predominated among patients with prostatitis. Using data from a nationwide survey of physician visits, we examined the most common symptoms reported by men at chronic prostatitis visits and contrasted the results with visits for benign prostatic hyperplasia (BPH).

METHODS

We analyzed 81,034 visits by men (18 years and older) to office-based physicians of all specialties in the National Ambulatory Medical Care Surveys of 1990 to 1996, using sampling weights to make national estimates. U.S. physicians selected by random stratified sampling completed visit forms that included patients' reasons for visits and physicians' diagnoses.

RESULTS

In 1990 to 1996, there were 765 visits (national estimate 1.5 million visits/yr; 95% confidence interval = 0.9 to 2.1) with a diagnosis of chronic prostatitis. Among chronic prostatitis visits, 20% were for pain, 19% for urinary symptoms, and 1% for sexual dysfunction. Among 2271 BPH visits, 2% were for pain, 33% for voiding complaints, and 1% for sexual dysfunction. The most common reason coded for chronic prostatitis visits was painful urination (14% of chronic prostatitis visits, but only 1.7% of BPH visits).

CONCLUSIONS

Pain was slightly more common than voiding complaints, but much more common than sexual dysfunction among chronic prostatitis visits. The most common reason for chronic prostatitis visits was painful urination, which was uncommon among patients with BPH. Pain distinguished chronic prostatitis from BPH better than any other urinary symptom.

Prevalence of bothersome genitourinary symptoms and diagnoses in younger men on routine primary care visits

OBJECTIVES

To assess the prevalence of bothersome genitourinary (GU) symptoms in younger men on routine primary care physician visits.

METHODS

One hundred six men aged 18 to 50 years were approached to complete a brief, self-administered survey that included the American Urological Association Symptom Index, a benign prostatic hyperplasia (BPH) Impact Index, and additional questions about GU pain and sexual dysfunction and about a history of GU diseases. Men with GU symptoms had their outpatient records reviewed.

RESULTS

Of the 101 respondents (mean age 36 years), 50% reported GU symptoms. Of these men, 25% were bothered by their symptoms and 17% wanted to talk about them with their physicians; 22% were worried that their GU symptoms might be due to prostate cancer; 27% of all men reported a history of at least one GU disease and 17% had more than one; 16% of all men had been to a urologist. Chart review for the 51 men with symptoms revealed physician documentation of GU symptoms in only 24% of cases and an abnormal GU examination in 8%. One third of reviewed charts documented a GU problem that visit. A broad spectrum of GU diagnoses was documented; no one cause predominated. Ninety percent of all men reported that primary care physicians should routinely ask younger men GU questions as part of their general healthcare.

CONCLUSIONS

The high prevalence of bothersome GU symptoms and diagnoses in younger men suggests that information about the clinical, functional, and quality of life implications of these symptoms needs to be collected in this population.

Prostate cancer screening and beliefs about treatment efficacy: a national survey of primary care physicians and urologists

PURPOSE

To describe practice patterns and beliefs of primary care physicians and urologists regarding early detection and treatment of prostate cancer.

SUBJECTS AND METHODS

National probability samples of primary care physicians (n=444) and urologists (n=394) completed mail survey instruments in 1995. Physicians were asked about their use of prostate-specific antigen (PSA) testing for men of different ages and their beliefs about the value of radical prostatectomy, external-beam radiation therapy, and watchful waiting for men with differing life expectancies.

RESULTS

Most primary care physicians report doing PSA tests during routine examination of men older than 50 years of age. The majority say they continue to do them on patients over 80 years and to refer men with abnormal values for biopsy. In contrast, only a minority of urologists would recommend PSA tests or biopsy for abnormal values for men over 75 years of age. More than 80% of primary care physicians and urologists doubt the value of radical prostatectomy for men with < 10 years of life expectancy; more primary care physicians than urologists see probable survival benefit in radiation therapy for patients with life expectancy < 10 years (48% versus 36%) or > 10 years (67% versus 53%). Thirteen percent of primary care physicians and only 3% of urologists consider watchful waiting to be as appropriate as aggressive therapy for men with > 10 years of life expectancy.

CONCLUSIONS

Primary care physicians are more aggressive about PSA testing and referral for biopsy than most urologists recommend. Both groups recommend PSA testing and believe that aggressive treatment is more beneficial than existing evidence indicates.

How common is prostatitis? A national survey of physician visits

PURPOSE

We used a national data base to explore the epidemiology of physician visits for genitourinary symptoms or a diagnosis of prostatitis.

MATERIALS AND METHODS

We analyzed 58,955 visits by men 18 years old or older to office based physicians of all specialties, as included in the National Ambulatory Medical Care Surveys from 1990 to 1994. Physicians selected by random sampling completed visit forms that included information on patient reasons for visits and physician diagnoses.

RESULTS

From 1990 to 1994, 5% of all ambulatory visits by men 18 years old or older included genitourinary symptoms as a reason for the visit. In almost 2 million visits annually prostatitis was listed as a diagnosis, including 0.7 million by men 18 to 50 years old and 0.9 million by those older than 50 years. Of the prostatitis visits 46 and 47% were to urologists and primary care physicians, respectively. A prostatitis diagnosis was assigned at 8 and 1% of all urologist and primary care physician visits, respectively. The odds of a prostatitis diagnosis were 13-fold greater at visits to urologists compared with visits to primary care physicians, and approximately 2-fold greater in the south than in the northeast. Surprisingly, compared with men 66 years old or older, prostatitis was more commonly diagnosed in men 36 to 65 than men 18 to 35 years old. When a prostatitis diagnosis was given, antimicrobial use was likely to be reported 45% of the time for men with and 27% for those without genitourinary symptoms. Visits to primary care physicians were more often associated with antimicrobial use than visits to urologists.

CONCLUSIONS

Genitourinary symptoms are a frequent reason for office visits by younger and older men, and prostatitis is a common diagnosis. Despite a report that less than 10% of prostatitis cases are bacterial, a much higher proportion of men in whom prostatitis is diagnosed receive antimicrobials.

Posterior tracheal wall diverticula-an unexpected finding

Two cases of asymptomatic posterior tracheal wall diverticula, one single and one multiple, found unexpectedly at laryngectomy are described. The embryonal development and pathogenesis of tracheal abnormalities are discussed, and possible clinical implications speculated upon.

Diagnosis and treatment of benign prostatic hyperplasia. Practice patterns of primary care physicians

OBJECTIVE

To define primary care physicians' (PCPs) practices in managing patients with benign prostatic hyperplasia [BPH], and to compare these practices to portions of the Agency for Health Care Policy and Research BPH guideline and urologists' practices.

DESIGN

Mail survey.

PARTICIPANTS

Nationwide random sample of PCPs and urologists, selected from the American Medical Association Registry.

METHODS

Initial mailing, postcard reminder, second mailing, telephone reminder, final mailing.

MAIN RESULTS

Primary care physicians (n = 444, response = 51%) reported seeing a median of 35 patients with BPH over the preceding year, in contrast to 240 for urologists (n = 394, response = 68%). Regarding tests recommended by the guideline, two thirds of PCPs reported rarely or never using the American Urological Association (AUA) symptom index, nearly all reported routinely performing digital rectal examinations, and many (66%) reported routinely ordering tests to determine the serum creatinine level. Although considered "optional" by the guideline, more than 90% of PCPs reported routinely ordering a prostate-specific antigen test, while infrequently using other optional tests. Regarding "not recommended" studies, a substantial minority reported selectively or routinely ordering intravenous pyelography (34%) and renal ultrasound (33%), while two thirds reported rarely or never ordering these tests. Eighty-six percent of PCPs reported prescribing medications for BPH over the preceding year; alpha blockers to a median of 12 patients, and finasteride to a median of 2. Variation in urology referral thresholds was suggested in responses to two patient scenarios.

CONCLUSIONS

Primary care physicians are actively managing patients with BPH. Some of their diagnostic evaluations vary from the recommendations of a national guideline and urologists' practices. Referral thresholds appear to vary considerably.

Cochlear implantation in a district general hospital: problems and complications in the first five years

Fifty-three patients, 34 adults and 19 children have been implanted over the first five years of the cochlear implant programmed at the North Riding Infirmary (NRI). For a small centre, based at a district general hospital, our complication rate compare favourably with others: 11.7 per cent adult and 10.5 per cent paediatric major complications. Data on all patients was gathered prospectively as part of the national cochlear implant programme, and we report and discuss all complications from this centre.

Medical malpractice implications of PSA testing for early detection of prostate cancer

Prostate cancer screening is controversial. We conducted a national survey of primary care physicians and urologists to examine their use of prostate-specific antigen testing and their views on medical liability issues involved.

Controversies in prostate cancer screening. Analogies to the early lung cancer screening debate

The current debate regarding early detection and aggressive treatment of prostate cancer is fueled by the absence of controlled studies defining the risks and benefits of prostate cancer screening, and by the lack of adequately powered trials demonstrating the benefit of curative treatment for early-stage prostate cancer. Pending the results of clinical trials in 10 to 15 years, advocates of early detection of prostate cancer with digital rectal examination and prostate-specific antigen have compared prostate cancer screening with the effective strategy of breast cancer screening, implying that prostate cancer screening should similarly reduce cancer mortality. They have also cited the high burden of disease, the acceptable operating characteristics of digital rectal examination and prostate-specific antigen, a stage shift among cases detected by screening, and the theoretical curability of early-stage disease as sufficient reasons to proceed with screening. These arguments, however, are reminiscent of earlier arguments in favor of lung cancer screening with chest x-ray examination and sputum cytology, a practice ultimately proven ineffective in clinical trials. We reviewed published articles on lung and prostate cancer screening and identified many parallels. While prostate cancer screening may one day prove effective, analogies between the current prostate cancer screening controversy and the older lung cancer screening debate should inject some caution regarding widespread dissemination of prostate cancer screening without experimental evidence that such screening does more good than harm.

Linkage of congenital isolated adrenocorticotropic hormone deficiency to the corticotropin releasing hormone locus using simple sequence repeat polymorphisms

Genetic screening techniques using simple sequence repeat polymorphisms were applied to investigate the molecular nature of congenital isolated adrenocorticotropic hormone (ACTH) deficiency. We hypothesize that this rare cause of hypocortisolism shared by a brother and sister with two unaffected sibs and unaffected parents is inherited as an autosomal recessive single gene mutation. Genes involved in the hypothalamic-pituitary axis controlling cortisol sufficiency were investigated for a causal role in this disorder. Southern blotting showed no detectable mutations of the gene encoding pro-opiomelanocortin (POMC), the ACTH precursor. Other candidate genes subsequently considered were those encoding neuroendocrine convertase-1, and neuroendocrine convertase-2 (NEC-1, NEC-2), and corticotropin releasing hormone (CRH). Tests for linkage were performed using polymorphic di- and tetranucleotide simple sequence repeat markers flanking the reported map locations for POMC, NEC-1, NEC-2, and CRH. The chromosomal haplotypes determined by the markers flanking the loci for POMC, NEC-1, and NEC-2 were not compatible with linkage. However, 22 individual markers defining the chromosomal haplotypes flanking CRH were compatible with linkage of the disorder to the immediate area of this gene on chromosome 8. Based on these data, we hypothesize that the ACTH deficiency in this family is due to an abnormality of CRH gene structure or expression. These results illustrate the useful application of high density genetic maps constructed with simple sequence repeat markers for inclusion/exclusion studies of candidate genes in even very small nuclear families segregating for unusual phenotypes.

Levels and identities of nonrhizobial microorganisms found in commercial legume inoculant made with nonsterile peat carrier

Sixty samples of commercial North American legume inoculants manufactured for sale in 1994 using nonsterile peat as carrier were tested for Rhizobium (or Bradyrhizobium) content and non-Rhizobium biological contaminant load. Products of three major producers of such inoculants for sale in Canada were examined. Viable Rhizobium content varied from 5.6 x 10(5) to 8.1 x 10(9) cells/g, while the contaminant load varied from 1.8 x 10(8) to 5.5 x 10(10) cfu/g. Most of the inoculants contained more nonrhizobial organisms than they did rhizobia. Identifications were made of the most numerous nonrhizobial bacteria occurring in 100 samples of inoculants collected in 1993 and 1994. The most commonly identified contaminant was Xanthomonas maltophilia. Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacter cloacae were also found at high levels in some products. Contaminant organisms capable of inhibiting rhizobial growth in plate culture were found in the products of all three manufacturers.

Constitutive human steroid 21-hydroxylase promoter gene and pseudogene activity in steroidogenic and nonsteroidogenic cells with the luciferase gene as a reporter

This study was directed toward initial comparison and characterization of the activities of the human steroid 21-hydroxylase gene (CYP21) and pseudogene (CYP21P) promoters. DNA fragments containing the promoter regions of CYP21 and CYP21P were amplified and cloned into promoterless luciferase reporter plasmids either containing or lacking an enhancer element. Cells of the nonsteroidogenic COS-1 cell line, and the steroidogenic Y-1 cell line were transiently transfected with these recombinant plasmids and a beta-galactosidase cotransfection control plasmid. Cellular lysates were analyzed for luciferase and beta-galactosidase activities. In the nonsteroidogenic system, transfectants with either the CYP21 or CYP21P upstream sequence in enhancer containing plasmids showed a 2.3 fold increase (p < .001) in light production over controls. In the steroidogenic Y-1 cell system, these same CYp21 and CYP21P transfectants showed a 14.3 (+/- 0.8) and 5.2 (+/- 0.6) fold increase in luciferase activity respectively (p < .001) Transfections with recombinant reporter plasmids lacking an enhancer produced light emission which was not significantly different than controls. These observations indicate that 1.) one or more of the 35 nucleotide differences between the CYP21 and CYP21P upstream regions alters a DNA recognition site important for transcriptional activation of this gene in steroidogenic cells, 2.) the steroidogenic milieu has a stimulatory effect on both CYP21 and CYP21P promoter activities, and 3.) based on the minimal promoter activity observed in either cell type transfected with constructs lacking an enhancer element, both of these promoter sequences are enhancer dependent under constitutive conditions in both steroidogenic and nonsteroidogenic cells.

The HLA-A3, Cw6,B47,DR7 extended haplotypes in salt losing 21-hydroxylase deficiency and in the Old Order Amish: identical class I antigens and class II alleles with at least two crossover sites in the class III region

The HLA-B47,DR7 haplotype in congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency contains a deletion of most of the active CYP21 gene and the entire adjacent C4B gene. The C4A gene produces a protein which is electrophoretically C4A but antigenically C4B. In the Old Order Amish, the HLA-B47,DR7 haplotype contains no deletion, but is immunologically identical to the CAH haplotype in both areas flanking the crossover region. We compared some of the genes in the MHC Class II and Class III regions in the Amish and CAH-linked haplotypes to define further the relationships between the two. The complement factor B (Bf) proteins differed, but no Bf RFLPs were identified. The complement factor 2 genes exhibited different BamHI RFLPs. Analyses of the tumor necrosis factor-alpha genes revealed the same NcoI restriction patterns. The RD genes contained microsatellites of the same size. Portions of the MHC Class II DR and DQ, and Class III CYP21 and C4 alleles were sequenced. The exon 2 sequences of DQ2 and DR7 were identical in the two haplotypes. In the Amish haplotype, both CYP21 and C4 gene pairs were present and functionally normal. The CAH haplotype had two sequence crossovers: from CYP21P to CYP21 in the 7th intron, and from C4A to C4B between codons 1106 (exon 26) and 1157 (exon 28). A model is proposed which accounts for the CAH-linked mutant haplotype arising from a nonmutant homologue via three crossings-over.

Ultrasound scattering from spherical tumours

The interaction of biomedical ultrasound with spherical tumours in the human body is investigated using analytic methods which predict the angular distribution of the ultrasound scattered by the tumour. Both the tumour and the surrounding tissue are considered to be lossy elastic media, which support shear-wave modes in addition to the familiar compressional-wave acoustic modes. Exact expressions for the angular distribution of the ultrasonic energy scattered by the tumour are used to illustrate graphically the behaviour of plane ultrasound wave interactions.

The human complement C4B/steroid 21-hydroxylase (CYP21) and complement C4A/21-hydroxylase pseudogene (CYP21P) intergenic sequences: comparison and identification of possible regulatory elements

We determined the 1.8 kb intergenic sequences between the human complement C4B gene and the active steroid 21-hydroxylase gene in two subjects, and between the C4A gene and the steroid 21-hydroxylase pseudogene in one subject. Comparison of these sequences with each other and with published homologues revealed no differences which were unique to either intergenic region. Sequence analysis revealed two copies of an AGGTCA motif in all sequences. This motif is common to steroidogenic enzyme gene promoters and to the response elements for nuclear hormone receptors. Similarities with human enhancers were also found.

Exon 7 Ncol restriction site within CYP21B (steroid 21-hydroxylase) is a normal polymorphism

A point mutation within exon 7 producing an amino acid coding change and a recognition site for the endonuclease Ncol has been reported in the HLA-Bw47-linked CYP21A pseudogene and some mutant CYP21B (steroid 21-hydroxylase) genes of patients with congenital adrenal hyperplasia (CAH). Whether this mutation is deleterious was not demonstrated. We analyzed DNA from various subjects for the presence of the exon 7 Ncol site: group 1, 10 normal subjects; group 2, 11 patients with salt-losing CAH; and group 3, 18 members of an Amish pedigree in which 10 expressed HLA-Bw47 not linked to CAH. Southern blots of Ncol-digested genomic DNA which were hybridized with CYP21 cDNA showed that four subjects of group 1 had a heterozygous Ncol pattern. In group 2, seven patients had the Ncol site; two of them were homozygous for the site and had deletions of both CYP21B genes. The other five were heterozygous for the Ncol site, which was linked to a CYP21B deletion and a HLA-Bw47 haplotype. In group 3, no one exhibited the exon 7 Ncol site. To map the Ncol sites to CYP21A or CYP21B in the normal subjects, DNA from the four Ncol heterozygous subjects was double digested with Ncol and Mbol and hybridized with CYP21 cDNA. Ncol-Mbol fragments unique to CYP21A were identified in all four, but the smaller CYP21B-specific fragments were not detected. Their genomic DNA in the region of exon 7 (bases +1167 to +2058) was then amplified, cloned, and sequenced.(ABSTRACT TRUNCATED AT 250 WORDS)

Association of DNA content and proliferative activity with clinical outcome in patients with diffuse mixed cell and large cell non-Hodgkin's lymphoma

Formalin-fixed and paraffin-embedded lymph node biopsy specimens from 52 untreated patients with newly diagnosed diffuse large cell (n = 48) or mixed cell (n = 4) non-Hodgkin's lymphoma (NHL) were analyzed for DNA content and proliferative activity (PA) by flow cytometry. The results obtained by flow cytometry were compared with the results of cytogenetic studies performed on 28 of the specimens. The median age of the patients was 65 years (range, 15-84 years) and the male to female ratio was 3 to 2. All patients were uniformly staged and uniformly treated with cyclophosphamide, doxorubicin, procarbazine, bleomycin, vincristine, and prednisone. The flow cytometric results were compared statistically by univariate analysis with the rate and duration of complete remission and survival. Tumors with low PA (greater than or equal to 80% of cells in G0/G1 phase) were found in 65% of the patients; 74% of those with low PA versus only 44% of those with high PA achieved an initial complete remission (P less than 0.02). DNA aneuploidy was detected in tumors of 56% of the patients and was associated with a significantly longer duration of complete remission (P less than 0.01). Both low PA and aneuploidy independently predicted longer survival. The predicted 2-year actuarial survival for patients with tumors with low PA was 68% versus 10% for those with high PA (P less than 0.01). Similarly, the 2-year survival of patients with aneuploid tumors was 60% versus 36% for those with diploid tumors (P less than 0.01). The combination of PA and DNA content categorized the patients into four groups with decreasing 2-year survivals: low PA/aneuploid (n = 20), 77%; low PA/diploid (n = 14), 57%; high PA/aneuploid (n = 9), 32%; high PA/diploid (n = 9), 0%. The flow cytometric results correlated well with those of the cytogenetic studies. We conclude that low PA and DNA aneuploidy, both separately and in combination, predict a favorable clinical outcome for patients with diffuse mixed cell and large cell NHL.