Growth hormone insensitivity and adipose tissue: tissue morphology and transcriptome analyses in pigs and humans

PURPOSE

Growth hormone receptor knockout (GHR-KO) pigs have recently been developed, which serve as a large animal model of Laron syndrome (LS). GHR-KO pigs, like individuals with LS, are obese but lack some comorbidities of obesity. The purpose of this study was to examine the histological and transcriptomic phenotype of adipose tissue (AT) in GHR-KO pigs and humans with LS.

METHODS

Intraabdominal (IA) and subcutaneous (SubQ) AT was collected from GHR-KO pigs and examined histologically for adipocyte size and collagen content. RNA was isolated and cDNA sequenced, and the results were analyzed to determine differentially expressed genes that were used for enrichment and pathway analysis in pig samples. For comparison, we also performed limited analyses on human AT collected from a single individual with and without LS.

RESULTS

GHR-KO pigs have increased adipocyte size, while the LS AT had a trend towards an increase. Transcriptome analysis revealed 55 differentially expressed genes present in both depots of pig GHR-KO AT. Many significant terms in the enrichment analysis of the SubQ depot were associated with metabolism, while in the IA depot, IGF and longevity pathways were negatively enriched. In pathway analysis, multiple expected and novel pathways were significantly affected by genotype, i.e. KO vs. controls. When GH related gene expression was analyzed, SOCS3 and CISH showed species-specific changes.

CONCLUSION

AT of GHR-KO pigs has several similarities to that of humans with LS in terms of adipocyte size and gene expression profile that help describe the depot-specific adipose phenotype of both groups.

Structural and proteomic repercussions of growth hormone receptor deficiency on the pituitary gland: Lessons from a translational pig model

Growth hormone receptor deficiency (GHRD) results in low serum insulin-like growth factor 1 (IGF1) and high, but non-functional serum growth hormone (GH) levels in human Laron syndrome (LS) patients and animal models. This study investigated the quantitative histomorphological and molecular alterations associated with GHRD. Pituitary glands from 6 months old growth hormone receptor deficient (GHR-KO) and control pigs were analyzed using a quantitative histomorphological approach in paraffin (9 GHR-KO [5 males, 4 females] vs. 11 controls [5 males, 6 females]), ultrathin sections tissue sections (3 male GHR-KO vs. 3 male controls) and label-free proteomics (4 GHR-KO vs. 4 control pigs [2 per sex]). GHR-KO pigs displayed reduced body weights (60% reduction in comparison to controls; p < .0001) and decreased pituitary volumes (54% reduction in comparison to controls; p < .0001). The volume proportion of the adenohypophysis did not differ in GHR-KO and control pituitaries (65% vs. 71%; p = .0506) and GHR-KO adenohypophyses displayed a reduced absolute volume but an unaltered volume density of somatotrophs in comparison to controls (21% vs. 18%; p = .3164). In GHR-KO pigs, somatotroph cells displayed a significantly reduced volume density of granules (23.5%) as compared to controls (67.7%; p < .0001). Holistic proteome analysis of adenohypophysis samples identified 4660 proteins, of which 592 were differentially abundant between the GHR-KO and control groups. In GHR-KO samples, the abundance of somatotropin precursor was decreased, whereas increased abundances of proteins involved in protein production, transport and endoplasmic reticulum (ER) stress were revealed. Increased protein production and secretion as well as significantly reduced proportion of GH-storing granules in somatotroph cells of the adenohypophysis without an increase in volume density of somatotroph cells in the adenohypophysis could explain elevated serum GH levels in GHR-KO pigs.

Effects of GHR Deficiency and Juvenile Hypoglycemia on Immune Cells of a Porcine Model for Laron Syndrome

Laron syndrome (LS) is a rare genetic disorder characterized by low levels of insulin-like growth factor 1 (IGF1) and high levels of growth hormone (GH) due to mutations in the growth hormone receptor gene (GHR). A GHR-knockout (GHR-KO) pig was developed as a model for LS, which displays many of the same features as humans with LS-like transient juvenile hypoglycemia. This study aimed to investigate the effects of impaired GHR signaling on immune functions and immunometabolism in GHR-KO pigs. GHR are located on various cell types of the immune system. Therefore, we investigated lymphocyte subsets, proliferative and respiratory capacity of peripheral blood mononuclear cells (PBMCs), proteome profiles of CD4− and CD4+ lymphocytes and IFN-α serum levels between wild-type (WT) controls and GHR-KO pigs, which revealed significant differences in the relative proportion of the CD4+CD8α− subpopulation and in IFN-α levels. We detected no significant difference in the respiratory capacity and the capacity for polyclonal stimulation in PBMCs between the two groups. But proteome analysis of CD4+ and CD4− lymphocyte populations revealed multiple significant protein abundance differences between GHR-KO and WT pigs, involving pathways related to amino acid metabolism, beta-oxidation of fatty acids, insulin secretion signaling, and oxidative phosphorylation. This study highlights the potential use of GHR-KO pigs as a model for studying the effects of impaired GHR signaling on immune functions.

A scalable, clinically severe pig model for Duchenne muscular dystrophy

Large animal models for Duchenne muscular dystrophy (DMD) are crucial for evaluation of diagnostic procedures and treatment strategies. Pigs cloned from male cells lacking DMD exon 52 (DMDΔ52) resemble molecular, clinical and pathological hallmarks of DMD, but die before sexual maturity and cannot be propagated by breeding. Therefore, we generated female DMD+/- carriers. A single founder animal had 11 litters with 29 DMDY/-, 34 DMD+/- as well as 36 male and 29 female wild-type offspring. Breeding with F1 and F2 DMD+/- carriers resulted in additional 114 DMDY/- piglets. With intensive neonatal management, the majority survived for 3-4 months, providing statistically relevant cohorts for experimental studies. Pathological investigations and proteome studies of skeletal muscles and myocardium confirmed the resemblance of human disease mechanisms. Importantly, DMDY/- pigs reveal progressive myocardial fibrosis and increased expression of connexin-43, associated with significantly reduced left ventricular ejection fraction already at age 3 months. Furthermore, behavioral tests provided evidence for impaired cognitive ability. Our breeding cohort of DMDΔ52 pigs and standardized tissue repositories provide important resources for studying DMD disease mechanisms and for testing novel treatment strategies.

MECHANISMS IN ENDOCRINOLOGY: Transient juvenile hypoglycemia in growth hormone receptor deficiency - mechanistic insights from Laron syndrome and tailored animal models

The aim of the study is to find possible explanations for vanishing juvenile hypoglycemia in growth hormone receptor deficiency (GHRD) in human patients and animal models. We reviewed parameters of glucose metabolism in distinct age groups into two human cohorts (Israeli and Ecuadorian) of Laron syndrome (LS) patients, a mouse model (Ghr-KO mouse) and provided additional data for a porcine model (GHR-KO pig). Juvenile hypoglycemia is a common symptom of GHRD and vanishes in adulthood. In the Israeli cohort, developing metabolic syndrome is associated with decreasing insulin sensitivity, insulinopenia and glucose intolerance, and increasing glucose levels with age. In the Ecuadorian patients and both animal models, insulin sensitivity is preserved or even enhanced. Alterations in food intake and energy consumption do not explain the differences in glucose levels; neither is the accumulation of body fat associated with negative effects in the Ecuadorian cohort nor in the animal models. A reduced beta-cell mass and resulting insulin secretory capacity is common and leads to glucose intolerance in Ghr-KO mice, while glucose tolerance is preserved in Ecuadorian patients and the GHR-KO pig. In human patients and the GHR-KO pig, a simultaneous occurrence of normoglycemia with the onset of puberty is reported. Reduced gluconeogenesis in GHRD is discussed to cause juvenile hypoglycemia and a counter-regulatory stimulation of gluconeogenesis can be hypothesized. A coherent study assessing endogenous glucose production and beta-cell capacity in the hypoglycemic and normoglycemic age group is needed. This can be performed in GHR-KO pigs, including castrated animals.

Growth hormone receptor knockout to reduce the size of donor pigs for preclinical xenotransplantation studies

BACKGROUND

Many genetically multi-modified donor lines for xenotransplantation have a background of domestic pigs with rapid body and organ growth. The intrinsic growth potential of porcine xeno-organs may impair their long-term function after orthotopic transplantation in non-human primate models. Since growth hormone is a major stimulator of postnatal growth, we deleted its receptor (GHR-KO) to reduce the size of donor pigs in one step.

METHODS

Heart weight and proteome profile of myocardium were investigated in GHR-KO and control pigs. GHR-KO mutations were introduced using CRISPR/Cas9 in an α1,3-galactosyltransferase (GGTA1)-deficient background expressing the human cluster of differentiation (hCD46) and human thrombomodulin (hTHBD) to generate quadruple-modified (4GM) pigs.

RESULTS

At age 6 months, GHR-KO pigs had a 61% reduced body weight and a 63% reduced heart weight compared with controls. The mean minimal diameter of cardiomyocytes was 28% reduced. A holistic proteome study of myocardium samples from the two groups did not reveal prominent differences. Two 4GM founder sows had low serum insulin-like growth factor 1 (IGF1) levels (24 ± 1 ng/mL) and reached body weights of 70.3 and 73.4 kg at 9 months. Control pigs with IGF1 levels of 228 ± 24 ng/mL reached this weight range three months earlier. The 4GM sows showed normal sexual development and were mated with genetically multi-modified boars. Offspring revealed the expected Mendelian transmission of the genetic modifications and consistent expression of the transgenes.

CONCLUSION

GHR-KO donor pigs can be used at an age beyond the steepest phase of their growth curve, potentially reducing the problem of xeno-organ overgrowth in preclinical studies.

Effect of Dietary Sodium Modulation on Pig Adrenal Steroidogenesis and Transcriptome Profiles

Primary aldosteronism is a frequent form of endocrine hypertension caused by aldosterone overproduction from the adrenal cortex. Regulation of aldosterone biosynthesis has been studied in rodents despite differences in adrenal physiology with humans. We, therefore, investigated pig adrenal steroidogenesis, morphology, and transcriptome profiles of the zona glomerulosa (zG) and zona fasciculata in response to activation of the renin-angiotensin-aldosterone system by dietary sodium restriction. Six-week-old pigs were fed a low- or high-sodium diet for 14 days (3 pigs per group, 0.4 g sodium/kg feed versus 6.8 g sodium/kg). Plasma aldosterone concentrations displayed a 43-fold increase (P=0.011) after 14 days of sodium restriction (day 14 versus day 0). Low dietary sodium caused a 2-fold increase in thickness of the zG (P<0.001) and an almost 3-fold upregulation of CYP11B (P<0.05) compared with high dietary sodium. Strong immunostaining of the KCNJ5 (G protein-activated inward rectifier potassium channel 4), which is frequently mutated in primary aldosteronism, was demonstrated in the zG. mRNA sequencing transcriptome analysis identified significantly altered expression of genes modulated by the renin-angiotensin-aldosterone system in the zG (n=1172) and zona fasciculata (n=280). These genes included many with a known role in the regulation of aldosterone synthesis and adrenal function. The most highly enriched biological pathways in the zG were related to cholesterol biosynthesis, steroid metabolism, cell cycle, and potassium channels. This study provides mechanistic insights into the physiology and pathophysiology of aldosterone production in a species closely related to humans and shows the suitability of pigs as a translational animal model for human adrenal steroidogenesis.

A decade of experience with genetically tailored pig models for diabetes and metabolic research

The global prevalence of diabetes mellitus and other metabolic diseases is rapidly increasing. Animal models play pivotal roles in unravelling disease mechanisms and developing and testing therapeutic strategies. Rodents are the most widely used animal models but may have limitations in their resemblance to human disease mechanisms and phenotypes. Findings in rodent models are consequently often difficult to extrapolate to human clinical trials. To overcome this ‘translational gap’, we and other groups are developing porcine disease models. Pigs share many anatomical and physiological traits with humans and thus hold great promise as translational animal models. Importantly, the toolbox for genetic engineering of pigs is rapidly expanding. Human disease mechanisms and targets can therefore be reproduced in pigs on a molecular level, resulting in precise and predictive porcine (PPP) models. In this short review, we summarize our work on the development of genetically (pre)diabetic pig models and how they have been used to study disease mechanisms and test therapeutic strategies. This includes the generation of reporter pigs for studying beta-cell maturation and physiology. Furthermore, genetically engineered pigs are promising donors of pancreatic islets for xenotransplantation. In summary, genetically tailored pig models have become an important link in the chain of translational diabetes and metabolic research.

Linkage between growth retardation and pituitary cell morphology in a dystrophin-deficient pig model of Duchenne muscular dystrophy

OBJECTIVE

Human patients with Duchenne muscular dystrophy (DMD) commonly exhibit a short stature, but the pathogenesis of this growth retardation is not completely understood. Due to the suspected involvement of the growth hormone/insulin-like growth factor 1 (GH/IGF1) system, controversial therapeutic approaches have been developed, including both GH- administration, as well as GH-inhibition. In the present study, we examined relevant histomorphological and ultrastructural features of adenohypophyseal GH-producing somatotroph cells in a porcine DMD model.

METHODS

The numbers and volumes of immunohistochemically labelled somatotroph cells were determined in consecutive semi-thin sections of plastic resin embedded adenohypophyseal tissue samples using unbiased state-of-the-art quantitative stereological analysis methods.

RESULTS

DMD pigs displayed a significant growth retardation, accounting for a 55% reduction of body weight, accompanied by a significant 50% reduction of the number of somatotroph cells, as compared to controls. However, the mean volumes of somatotroph cells and the volume of GH-granules per cell were not altered. Western blot analyses of the adenohypophyseal protein samples showed no differences in the relative adenohypophyseal GH-abundance between DMD pigs and controls.

CONCLUSION

The findings of this study do not provide evidence for involvement of somatotroph cells in the pathogenesis of growth retardation of DMD pigs. These results are in contrast with previous findings in other dystrophin-deficient animal models, such as the golden retriever model of Duchenne muscular dystrophy, where increased mean somatotroph cell volumes and elevated volumes of intracellular GH-granules were reported and associated with DMD-related growth retardation. Possible reasons for the differences of somatotroph morphology observed in different DMD models are discussed.

Mild maternal hyperglycemia in INS C93S transgenic pigs causes impaired glucose tolerance and metabolic alterations in neonatal offspring

Alongside the obesity epidemic, the prevalence of maternal diabetes is rising worldwide, and adverse effects on fetal development and metabolic disturbances in the offspring's later life have been described. To clarify whether metabolic programming effects are due to mild maternal hyperglycemia without confounding obesity, we investigated wild-type offspring of INS^C93S transgenic pigs, which are a novel genetically modified large-animal model expressing mutant insulin (INS) C93S in pancreatic β-cells. This mutation results in impaired glucose tolerance, mild fasting hyperglycemia and insulin resistance during late pregnancy. Compared with offspring from wild-type sows, piglets from hyperglycemic mothers showed impaired glucose tolerance and insulin resistance (homeostatic model assessment of insulin resistance: +3-fold in males; +4.4-fold in females) prior to colostrum uptake. Targeted metabolomics in the fasting and insulin-stimulated state revealed distinct alterations in the plasma metabolic profile of piglets from hyperglycemic mothers. They showed increased levels of acylcarnitines, gluconeogenic precursors such as alanine, phospholipids (in particular lyso-phosphatidylcholines) and α-aminoadipic acid, a potential biomarker for type 2 diabetes. These observations indicate that mild gestational hyperglycemia can cause impaired glucose tolerance, insulin resistance and associated metabolic alterations in neonatal offspring of a large-animal model born at a developmental maturation status comparable to human babies.

Editor's choice: Mild maternal hyperglycemia causes impaired glucose tolerance and metabolic alterations in wild-type neonatal offspring of INS^C93S transgenic pigs, a novel large animal model for mutant INS gene-induced diabetes of youth (MIDY).

Growth hormone receptor-deficient pigs resemble the pathophysiology of human Laron syndrome and reveal altered activation of signaling cascades in the liver

OBJECTIVE

Laron syndrome (LS) is a rare, autosomal recessive disorder in humans caused by loss-of-function mutations of the growth hormone receptor (GHR) gene. To establish a large animal model for LS, pigs with GHR knockout (KO) mutations were generated and characterized.

METHODS

CRISPR/Cas9 technology was applied to mutate exon 3 of the GHR gene in porcine zygotes. Two heterozygous founder sows with a 1-bp or 7-bp insertion in GHR exon 3 were obtained, and their heterozygous F1 offspring were intercrossed to produce GHR-KO, heterozygous GHR mutant, and wild-type pigs. Since the latter two groups were not significantly different in any parameter investigated, they were pooled as the GHR expressing control group. The characterization program included body and organ growth, body composition, endocrine and clinical-chemical parameters, as well as signaling studies in liver tissue.

RESULTS

GHR-KO pigs lacked GHR and had markedly reduced serum insulin-like growth factor 1 (IGF1) levels and reduced IGF-binding protein 3 (IGFBP3) activity but increased IGFBP2 levels. Serum GH concentrations were significantly elevated compared with control pigs. GHR-KO pigs had a normal birth weight. Growth retardation became significant at the age of five weeks. At the age of six months, the body weight of GHR-KO pigs was reduced by 60% compared with controls. Most organ weights of GHR-KO pigs were reduced proportionally to body weight. However, the weights of liver, kidneys, and heart were disproportionately reduced, while the relative brain weight was almost doubled. GHR-KO pigs had a markedly increased percentage of total body fat relative to body weight and displayed transient juvenile hypoglycemia along with decreased serum triglyceride and cholesterol levels. Analysis of insulin receptor related signaling in the liver of adult fasted pigs revealed increased phosphorylation of IRS1 and PI3K. In agreement with the loss of GHR, phosphorylation of STAT5 was significantly reduced. In contrast, phosphorylation of JAK2 was significantly increased, possibly due to the increased serum leptin levels and increased hepatic leptin receptor expression and activation in GHR-KO pigs. In addition, increased mTOR phosphorylation was observed in GHR-KO liver samples, and phosphorylation studies of downstream substrates suggested the activation of mainly mTOR complex 2.

CONCLUSION

GHR-KO pigs resemble the pathophysiology of LS and are an interesting model for mechanistic studies and treatment trials.

The Munich MIDY Pig Biobank - A unique resource for studying organ crosstalk in diabetes

OBJECTIVE

The prevalence of diabetes mellitus and associated complications is steadily increasing. As a resource for studying systemic consequences of chronic insulin insufficiency and hyperglycemia, we established a comprehensive biobank of long-term diabetic INSC94Y transgenic pigs, a model of mutant INS gene-induced diabetes of youth (MIDY), and of wild-type (WT) littermates.

METHODS

Female MIDY pigs (n = 4) were maintained with suboptimal insulin treatment for 2 years, together with female WT littermates (n = 5). Plasma insulin, C-peptide and glucagon levels were regularly determined using specific immunoassays. In addition, clinical chemical, targeted metabolomics, and lipidomics analyses were performed. At age 2 years, all pigs were euthanized, necropsied, and a broad spectrum of tissues was taken by systematic uniform random sampling procedures. Total beta cell volume was determined by stereological methods. A pilot proteome analysis of pancreas, liver, and kidney cortex was performed by label free proteomics.

RESULTS

MIDY pigs had elevated fasting plasma glucose and fructosamine concentrations, C-peptide levels that decreased with age and were undetectable at 2 years, and an 82% reduced total beta cell volume compared to WT. Plasma glucagon and beta hydroxybutyrate levels of MIDY pigs were chronically elevated, reflecting hallmarks of poorly controlled diabetes in humans. In total, ∼1900 samples of different body fluids (blood, serum, plasma, urine, cerebrospinal fluid, and synovial fluid) as well as ∼17,000 samples from ∼50 different tissues and organs were preserved to facilitate a plethora of morphological and molecular analyses. Principal component analyses of plasma targeted metabolomics and lipidomics data and of proteome profiles from pancreas, liver, and kidney cortex clearly separated MIDY and WT samples.

CONCLUSIONS

The broad spectrum of well-defined biosamples in the Munich MIDY Pig Biobank that will be available to the scientific community provides a unique resource for systematic studies of organ crosstalk in diabetes in a multi-organ, multi-omics dimension.

[Gender differences in vascular medicine]

In vascular medicine only a few studies concerning gender differences in vascular diseases, course of the disease and therapy exist. Risk factors are allocated differently between men and women with different influences on cardiovascular diseases. Diabetic women do have a particular high risk. The proportion of women smokers with a risk for aggravation of the other risk factors is increased. In young female smokers the hypoplastic aortoiliac syndrome is a special course of peripheral arterial disease associated with a bad prognosis. The benefit of hormone replacement therapy in vascular diseases of postmenopausal women has not yet been demonstrated. On the other hand testosterone seems to have a favourable effect on vascular diameter and endothelium of coronaries. Women with peripheral arterial disease represent high risk patients with a particular risk for cardiovascular letality. Periprocedural complications of the analysed operations or interventions are found more frequent in women. Furthermore the disease is in an advanced stage when treated. Especially men with asymptomatic high grade carotid stenosis benefit more from an operation than women because of the higher risk for ischemic stroke. Unfortunately the benefit of the operation in women is neutralized by the higher rate of periprocedural complications. Some studies demonstrate the gender bias in treatment: women seldom receive revascularisation and guideline therapy as frequently as men. The same is true with thromboembolic prophylaxis concerning in hospital patients. In pharmacotherapy women have in result of metabolism more side effects. Additionally women are underrepresented in drug admission studies compared to their percentage of population and gender prevalence of diseases. Further studies concerning gender differences in vascular medicine are definitely needed.

The UCSC Genome Browser Database

The University of California Santa Cruz (UCSC) Genome Browser Database is an up to date source for genome sequence data integrated with a large collection of related annotations. The database is optimized to support fast interactive performance with the web-based UCSC Genome Browser, a tool built on top of the database for rapid visualization and querying of the data at many levels. The annotations for a given genome are displayed in the browser as a series of tracks aligned with the genomic sequence. Sequence data and annotations may also be viewed in a text-based tabular format or downloaded as tab-delimited flat files. The Genome Browser Database, browsing tools and downloadable data files can all be found on the UCSC Genome Bioinformatics website (http://genome.ucsc.edu), which also contains links to documentation and related technical information.

A kinship analysis of asthma among the Hutterites

A formal kinship analysis of asthma in a large Hutterite kindred indicates that cases are significantly more related to one another than are age matched controls. The higher kinship coefficient is shown to be due to an increased probability of the condensed identity state delta 8 which, in turn, is shown to be due to an increased probability of detailed identity state delta 10.

Markov chain Monte Carlo linkage analysis of complex quantitative phenotypes

We report a Markov chain Monte Carlo analysis of the five simulated quantitative traits in Genetic Analysis Workshop 12 using the Loki software. Our objectives were to determine the efficacy of the Markov chain Monte Carlo method and to test a new scoring technique. Our initial blind analysis, on replicate 42 (the "best replicate") successfully detected four out of the five disease loci and found no false positives. A power analysis shows that the software could usually detect 4 of the 10 trait/gene combinations at an empirical point-wise p-value of 1.5 x 10(-4).

Increased damage from fires in logged forests during droughts caused by El Niño

In 1997-98, fires associated with an exceptional drought caused by the El Niño/Southern Oscillation (ENSO) devastated large areas of tropical rain forests worldwide. Evidence suggests that in tropical rainforest environments selective logging may lead to an increased susceptibility of forests to fire. We investigated whether this was true in the Indonesian fires, the largest fire disaster ever observed. We performed a multiscale analysis using coarse- and high-resolution optical and radar satellite imagery assisted by ground and aerial surveys to assess the extent of the fire-damaged area and the effect on vegetation in East Kalimantan on the island of Borneo. A total of 5.2 +/- 0.3 million hectares including 2.6 million hectares of forest was burned with varying degrees of damage. Forest fires primarily affected recently logged forests; primary forests or those logged long ago were less affected. These results support the hypothesis of positive feedback between logging and fire occurrence. The fires severely damaged the remaining forests and significantly increased the risk of recurrent fire disasters by leaving huge amounts of dead flammable wood.

Extracorporeal shockwave lithotripsy of 2000 urinary calculi with the modulith SL-20: success and failure according to size and location of stones

PURPOSE

We analyzed the successes and failures of SWL in the treatment of 2016 urinary calculi stratified according to size and position in the urinary tract.

METHODS

All the patients were treated with a Modulith SL-20 (Storz Medical).

RESULTS

The overall stone-free rate, regardless of the size and position of the stone, was 87.4%. The rate was different for kidney and ureteral stones. The stone-free rate observed for the different positions of the calculi within the kidney was upper calix 89.2%, middle calix 90.5% lower calix 84.8%, and renal pelvis 86.0%. For staghorn calculi, the stone-free rate was 60.0%. The stone-free rate for the different positions of calculi within the ureter was: upper ureter 84.3%, iliac ureter 82.4%, and pelvic ureter 91.0%. For calculi >24 mm, the retreatment rate increased, and the success rate dropped sharply.

CONCLUSION

Extracorporal shockwave lithotripsy should be the first therapeutic option for urinary calculi of <24 mm regardless of their position in the urinary tract.

Genetic dissection of a complex trait

A number of genetic and statistical tools were applied to various partitions of the simulated data to identify susceptibility loci, relevant environmental factors, and their interaction(s). The distribution of genotypes at D1G24 among affected children in the first population was found to differ significantly from Hardy-Weinberg expectation. Two transmission/disequilibrium tests identified the preferential transmission of allele 1 as the source of the disequilibrium. Simple contingency table analysis revealed a positive association between exposure to environmental factor E1 and disease phenotype. Multipoint linkage analyses on various subsets of the data identified three "signal" regions (in addition to the aforementioned D1G24) localized at D1G9-10, D3G45, and D5G38. The even numbered chromosomes appeared to be devoid of susceptibility loci. Further analyses of subsamples of affected sib pairs, selected according to their disease phenotype and their exposure to E1, clarified some linkage relationships, particularly for D3G45, thereby suggesting the presence of a specific gene x environment interaction. Logistic analysis designed to clarify the relationship between disease phenotype and two risk factors (E1 exposure and the presence of allele 1 at D1G24) in the first population, revealed a significantly negative interaction which, upon learning the details of the generating model, we now attribute to the presence of heterogeneity.

Markov chain Monte Carlo linkage analysis of a complex qualitative phenotype

We tested a new computer program, LOKI, that implements a reversible jump Markov chain Monte Carlo (MCMC) technique for segregation and linkage analysis. Our objective was to determine whether this software, designed for use with continuously distributed phenotypes, has any efficacy when applied to the discrete disease states of the simulated data from the Mordor data from GAW Problem 1. Although we were able to identify the genomic location for two of the three quantitative trait loci by repeated application of the software, the MCMC sampler experienced significant mixing problems indicating that the method, as currently formulated in LOKI, was not suitable for the discrete phenotypes in this data set.

Locoregional/systemic chemotherapy of locally advanced/metastasized pancreatic cancer with a combination of mitomycin-C and gemcitabine and simultaneous follow-up by imaging methods and tumor markers

Stimulated by surprising results in the first 7 patients treated with intraarterial/systemic chemotherapy with a combination of Mitomycin-C + Gemcitabine we now report on the data of 28 pancreatic cancer patients in comparison to 15 patients treated with gemcitabine alone(1000 mg/m2). Tumor response was evaluated on the basis of imaging methods, tumor markers and life quality parameters like body weight, pains and Karnofsky index etc. Tumor markers were monthly determined, imaging methods every 1-3 months. The locoregional/systemic approach included 3 week cycles with i.a. application of mitomycin-C + gemcitabine on day 1 and i.v. application of gemcitabine on days 8 and 15. The alltogether 125 cycles (mean 4 cycles per patient) resulted in 43% PR (n = 12), 1 CR (3%), 255 MR, 11% SD and 18% PD in the imaging methods and 20% CR, 60% PR, 4% MR and 12% SD in the course of the relevant tumor markers. Progression free survival amounted to a median of 7.5 (6) months defined by imaging methods (tumor markers). Second line treatments following new progress after effective locoregional approach with gemcitabine or a combination of gemcitabine + oxaliplatin did not result in a new tumor regression. However, third line therapy trials in 3 patients with high dose 5-FU or CPT 11 induced new antitumoral efficacy (survival of these tumors > 15, > 17 and > 28 months, n = 2 M1, n = 1 T3M0). About 75% of patients reported on a relevant benefit of life quality parameters. Side effects are on principle comparable to those of gemcitabine monotherapy, except for a tendency to a higher rate of pulmonary complications and 1 HUS observed. Even if not compared in a randomized study locoregional/systemic combined treatment modality seems to result in a higher rate of abjective tumor response defined by imaging methods as well as tumormarkers. Comparing tumor marker and imaging response to therapy CA 19-9 often showed a more rapid and subtle answer to therapy and an earlier new increase suggesting tumor markers as an essential part in the follow-up of these patients in order to optimize the patient's palliative treatment. Our results should stimulate the clinicians to rediscuss the chemosensitivity of exocrine pancreatic cancer and to perform prospective randomized studies focusing on combined gemcitabine approaches.

Patients with a malignant tumor have more extended thrombosis than patients without

Changes in the coagulability or rheology of the blood are supposed to cause an increased frequency of thrombosis in patients with a malignant tumor. These procoagulopathic disorders may not only increase the frequency of thrombosis but may also enlarge the extent of the thrombosis. The authors retrospectively analyzed, therefore, the extension of thrombosis in patients with and without a malignant tumor. From 1991 to 1995 in the University Hospital Essen 489 consecutive cases of thrombosis were diagnosed. The diagnosis was made by color Doppler sonography or phlebography; 230 patients (47%) suffered from a malignant tumor (110 men, 120 women). To exclude the influence of the patient's age on the extension of the thrombosis the authors distinguished three different age groups. In the tumor group aged from 21 to 40 years they found 10 large (iliacal, femoral, and crural veins), six medium (femoral and crural veins), and four small thromboses (crural veins). In the tumor group aged from 41 to 60 years they found 38 large, 24 medium, and 27 small thromboses. In the group without a tumor aged from 21 to 40 years they found seven large, 13 medium, and 28 small thromboses, and in the group aged from 41 to 60 years, 12 large, 29 medium, and 41 small thromboses. The difference between the two groups supports the assumption that in patients suffering from a malignant tumor, thromboses tend to be more extended than in patients without a malignant tumor.

Association of subclavian and jugular vein thrombosis: color doppler sonographic evaluation

In case of clinical symptoms of subclavian vein thrombosis a phlebographic or color Doppler sonographic investigation should be performed. Phlebography is a sensitive method to exclude the thrombosis in the subclavian vein but not in the jugular vein. Color Doppler sonography additionally gives information about the surrounding tissue and the jugular vein. The authors analyze their color Doppler sonographic data, first, to evaluate the association of internal jugular and subclavian vein thrombosis and, second, to demonstrate the necessity for a color Doppler investigation. Of 213 patients who suffered from a thrombosis, 93 had a subclavian vein thrombosis, 64 had a combined thrombosis in the internal jugular and subclavian vein, and 56 had an isolated internal jugular vein thrombosis. There is a high association between subclavian and internal jugular vein thrombosis, and a color Doppler investigation of both the subclavian and internal jugular veins is necessary.

[Diagnosis and therapy of hypothenar hammer syndrome]

Traumatic injuries of arteries lead to acute bleeding or ischemia. In the hand, which is perfused by two arteries, this symptom could be missed. The hypothenar hammer syndrome is a traumatic occlusion of the distal arteria ulnaris. Dependent on the mechanism of the trauma the clinical symptoms may appear late. A specific angiographic or duplex sonographic diagnostic investigation is necessary to show the arterial occlusion. There is no proven therapeutic procedure. Exact diagnosis of the occlusion as an effect of the trauma is important for the patient and is the basis of any therapeutic intervention.

[Duplex ultrasound imaging of vascularization in venous thrombosis]

Vascularization of venous thrombosis. The degree of organisation of an intravenous thrombus is important for therapeutic interventions and the postthrombotic damage. Changes in echogenicity have already been described in B-mode sonography. We investigated 7 thrombosis in the jugular vein looking for intra-thrombotic vessels that occur during the organisation. In 3 thrombosis arterial vessels were found from the 12th to the 17th day. Such arterial vessels appeared only in a short range of time and only in circumscript areas of the thrombus. The intra-vitam documentation of arterial vessels in an organizating intravenous thrombus may give information about the mechanism of thrombogenesis and about the degree of organisation.

[Ischemia of the arm with finger necroses: differential carpal tunnel syndrome and thoracic outlet syndrome diagnosis]

Upper extremity ischemia with finger necrosis: carpal-tunnel syndrome or thoracic outlet syndrome? A 26-year-old male patient complained of pain paraesthesia in the right upper extremity while working with the arm elevated. After electrophysiological diagnosis of a carpal-tunnel-syndrome the patient received surgical treatment. Following this treatment he developed acral necrosis at the fingers. Additional diagnostic effort let to the diagnosis of a thoracic-outlet-syndrome due to a cervical rib. This case report and a review of the literature show that electrophysiological investigations alone can not differentiate the carpal-tunnel-syndrome from the thoracic-outlet-syndrome. Thus an operative release of a carpal-tunnel should not be performed until the arterial perfusion of the upper extremity has been judged.

[Renal carcinoma and solitary pulmonary nodule]

Renal cell carcinoma with solitary metastasis detected at the time of diagnosis has been much discussed and its excision is considered to achieve favorable results. Herein we describe a patient with a solitary pulmonary lesion coexisting with a large renal cell carcinoma. The patient was submitted to radical surgery and the pathological analysis revealed a benign pulmonary tumor with no relationship to the renal cancer.

[Color-coded 2-dimensional Doppler echocardiography. Initial clinical experiences]

A new technology based on the Doppler principle for ultrasound has recently enabled the real-time visualization of cardiac blood flow by superposition of coloured flow information onto a two-dimensional echocardiogram. This study presents typical flow patterns in standard echocardiographic views, obtained from normal subjects and patients with acquired valvular or congenital heart diseases. Diagnostic possibilities and limitations of colour-coded Doppler echocardiography are discussed.

Transesophageal two-dimensional echocardiography: comparison of ultrasonic and anatomic sections

Conventional 2-dimensional echocardiography has become a well-established tool for evaluating cardiovascular diseases. Recent introduction of 2-dimensional transesophageal echocardiography has widened the ultrasonic examination possibilities of the heart and great arteries. The 6 standard transesophageal transducer positions that have proved representative and of diagnostic value are described. To facilitate structure identification and interpretation of anatomic relations, transesophageal recordings were compared with corresponding anatomic sections.

[2-dimensional transesophageal echocardiography: comparison of echocardiographic and anatomic section pictures]

Conventional two-dimensional echocardiography has become a well established tool for evaluation of cardiovascular diseases. Recent introduction of two-dimensional transesophageal echocardiography has widened the ultrasonic examination possibilities for the heart and the great vessels. This paper describes 6 standard transesophageal transducer positions which have proven to be representative and of diagnostic value. In order to facilitate structure identification and interpretation of the anatomic relation transesophageal recordings were compared with corresponding anatomic sections.

[Stage IIIB and IVB Hodgkin's disease. Response to chemotherapy, relapses, survival rates (author's transl)]

Thirty-two of 71 (45%) stage IIIB and IVB patients up to the age of 60 achieved a complete remission (CR) by initial COPP-chemotherapy. Twelve additional cases were free of symptoms after COPP, but showed persistent disease at postprimary laparotomy or within 3 months after cessation of chemotherapy. Forty-four per cent (n = 17) of this initial COPP failures could also be brought to CR by ABVD-chemotherapy or/and radiotherapy within 7 to 51 months. Cases with lymphocytic depletion reached CR in only 31% (N = 5/16) in comparison to 80% (n = 44/55) of the three other histological subtypes. Without additional consolidation therapy 60% relapsed, but only 11% after adjuvant total-nodal irradiation. An increase of side effects after therapy has not been observed so far. Patients with once attained CR have a survival probability of 93% after nearly 8 years from diagnosis. For the whole stage IIIB/IVB group the values were 85% up to the age of 30 (n = 28) and 60% for the age group of 31-60 (N = 43). They were clearly higher than in the 1966-1971 patients who showed values o 39% nd 41%, respectively. Beyond the stage of 60 (n = 15) the survival probability of 10% after 3 years in comparison to former 15% revealed no improvement.

[Survival rates in Hodgkin's disease in relation to histological subtypes (author's transl)]

Due to advantages of diagnostic and therapeutic progress the five-year-survival rates for 3 histological subtypes have become comparable in 322 patients with Hodgkin's disease during the years 1972 to 1979. Five-year-survival was 96% for the predominantly lymphocytic type, 90% for the nodular sclerosing type and 77% for the mixed cell type. Survival for all types together was 84% after 5 years and 80% after 7 years. The lymphocytic depletion type had a much worse prognosis with a five-year-survival of 31%. Apart from a reduced incidence of nodular sclerosis after the 40th year of life the histological forms were evenly spread between age groups and sexes On the other hand there were relationships between histological type and clinical stage.

[Survival rates and reduction or mortality in Hodgkin's disease in relation to age of the patient (author's transl)]

Survival rates were calculated in 550 patients with Hodgkin's disease during the years 1966 to 1979 according to decade of age and were classified into three significantly different groups. The patients have been investigated according to a standard procedure since 1972 and the major part was treated intensively. The five-year-survival rate was 95% for the group under 30 years of age, 75% for the group between 31 and 60 years and 47% for the older group. For the three comparative groups during 1966 to 1971 the rates of 76%, 60% and 40% were markedly lower. Mortality in the young and middle age groups has decreased in Hamburg since 1975. Due to the continued above average death rate after the 60th year of life this development is not sufficiently noticeable in the total group. A similar tendency is shown in the GFR mortality statistics. With increased use of diagnostic and therapeutic possibilities the age of the patient becoming one of the most important prognostic features in Hodgkin's disease.

[Serodiagnosis of malaria (author's transl)]

Homologous and heterologous malaria pathogens were used as antigens for the determination of malaria antibodies by indirect immunofluorescence. Homologous antibodies fell in the second half year, after successful treatment, down to the limit of demonstrability. In inhabitants of endemic malarial areas, who lived in the German Federal Republic, signs of a fall in antibodies could be observed after about 30 months. The predominance of particular malaria pathogens of the country of origin was recognizable in the antibody spectrum of these persons. Malaria antibody findings of three comparable groups of exposed persons under chemoprophylaxis ought to provide pointers to the parasitemias which had occurred and which were held responsible for the antibody production. Persons without chemoprophylaxis from malarial areas served as controls. The markedly deviating results of the antibody findings in the serum donors can only be explained by more seldom parasitemias in persons with adequate chemoprophylaxis.