Prevalence of 845G>A HFE mutation in Slavic populations: an east-west linear gradient in South Slavs

AIM

To compare A allele frequencies of the 845G>A mutation of 10 Slavic populations in central, eastern, and southern Europe between each other and with other European populations.

METHODS

The 845G>A mutation from the DNA of 400 Polish neonates collected in 2005-2006 was analyzed by polymerase chain reaction-restriction fragment length polymorphism. The data were compared with reports from other countries.

RESULTS

We identified 381 GG homozygotes, 18 GA heterozygotes, and 1 AA homozygote. The 845A allele frequency was 2.5%, which makes the summary figure for Poland from this and previous studies 3.5%. The average prevalence for Poland and other West Slavic countries was 3.6%, similar to Russia (inhabited by the East Slavs, 3.5%). The average prevalence in South Slavic countries was 2.2%, gradually decreasing from 3.6% in Slovenia to 0% in Bulgaria, with a longitudinal linear gradient (adjusted R(2)=0.976, P<0.001).

CONCLUSIONS

The West and East Slavs, together with Finland, Estonia, Germany, Austria, Hungary, Slovenia, and Croatia, form a group with 845A allele frequencies between 3% and 4%. In the South Slavs, there is a gradual decline in the prevalence of 845A allele from northwest to southeast, with a surprisingly exact east-west linear gradient.

[Shortage and need of physicians in Germany? Questions addressed to health services research]

The problem of shortage of physicians has been discussed controversially in Germany for years, and the different positions of the interest groups involved have not been resolved. The question of the present and anticipated future requirement of physicians is central for an appropriate and necessary medical care of the population. In the analysis, supply and demand of medical care have to be distinguished. Relatively reliable data do exist for the supply of physicians; however, the changing number of working hours that male and--in particular female--physicians are willing to contribute should be taken into consideration. Reliable data for the future demand are presently not available. Several variables (e.g., demography, disease spectrum of an aging society, medical progress, the changing rules of working hours, and the shift of medical care between hospital and practice care) depend on future developments. Considering the existing serious indicators of a growing shortage of physicians, it is recommended to put more effort into the scientific investigation of these factors. More profound data should improve the basis for decisions in health and education politics.

A single dose of intravenous zoledronate prevents glucocorticoid therapy-associated bone loss in acute flare of Crohn's disease, a randomized controlled trial

OBJECTIVES

To assess the effectiveness and safety of zoledronate (ZOL) in preventing glucocorticoid therapy-associated bone loss in patients with acute flare of Crohn's disease (CD) in a randomized, double-blind, placebo-controlled trial.

METHODS

Forty CD patients starting a glucocorticoid therapy (60 mg prednisolone per day) for acute flare (CD activity index (CDAI) >220) were randomized to compare the effect of ZOL (4 mg intravenous, n=20) or placebo (n=20) on change in lumbar bone mineral density (BMD). All patients received calcium citrate (800 mg) and colecalciferol (1,000 IU) daily. Dual energy X-ray absorptiometry (DXA) of the lumbar spine (L1-L4) was performed at baseline and day 90. Follow-up examinations at day 1/7/14/30 and 90 included laboratory tests and adverse event/serious adverse events reports.

RESULTS

Thirty-six patients were available for per-protocol analysis. With placebo (n=18), a decrease in BMD was seen (T-score: -0.98 ± 0.8, day 0 and -1.25 ± 0.77, day 90, P=0.06), with ZOL (n=18) BMD increased (-1.15 ± 1.02, day 0 and -0.74 ± 1.09, day 90, P=0.03). The change in BMD under placebo (-0.26 ± 0.21) vs. ZOL (+0.41 ± 0.19) was highly significant (P=0.006). In all, 14 out of 18 patients with ZOL had an increase in BMD (+0.64 ± 0.48), 12 of 18 with placebo a decrease (-0.50 ± 0.39). Changes of clinical findings and laboratory results of inflammation (leukocytes, platelets, and C-reactive protein) were the same in- and between-groups throughout the study. With ZOL, serum bone degradation marker β-Cross-Laps decreased. Study medication was safe and well tolerated.

CONCLUSIONS

ZOL is effective in preventing glucocorticoid therapy-induced bone loss in patients with acute flare of CD and should be considered whenever a glucocorticoid therapy is started in CD patients.

An age-related decrease in factor V Leiden frequency among Polish subjects

Factor V Leiden (G1691A FV mutation) is a widely acknowledged risk factor of deep vein thrombosis, including pulmonary embolism as the most serious complication. However, its high prevalence of ~5%in the Caucasian population might be related to an unknown evolutionary advantage. It might exert a beneficial effect on the carrier, e.g. protecting women from excessive bleeding during labour or allowing increased survival in severe sepsis or with other inflammatory diseases. The aim of our study was to verify or contradict the hypothesis of a favourable association between the A allele (A1691) and longevity in the Polish population. For this purpose, the G1691A mutation was analyzed by PCR-RFLP in 1016 Poles: 400 neonates (187 female and 312 male), 184 healthy adults (129 female and 55 male), and 432 long-lived individuals (age ≥95 years: 343 women and 89 men). Frequencies of G1691A carriers and the A1691 allele in long-lived individuals (0.2% and 0.1%, respectively) were significantly lower than in neonates (4.2% and 2.2%, respectively) and adults (3.3% and 1.6%). The frequency of the G1691A factor V Leiden mutation decreased with age, which indicates a shorter survival time among A1691 allele carriers in the Polish population.

[A prospective comparison of video colonoscopy and CT colonography in asymptomatic patients screened for colorectal cancer]

BACKGROUND AND OBJECTIVE

It was the aim of this study to compare the sensitivity and specificity of low-dose CT colonography (CTC) with that of optical colonoscopy (OC) in asymptomatic patients undergoing these tests in a screening program for colonic cancer.

PATIENTS AND METHODS

58 patients (mean age 62.6 years) were included. They underwent low dose CTC and, immediately afterwards, colonoscopy. The colonoscopists were unaware of the CTC findings. A "second look" was performed if a lesion seen in CTC had been missed in the first colonoscopy.

RESULTS

A total of 150 lesions were detected and histologically confirmed. 136 were found to be polypoid lesions, classified as either hyperplastic polyps (n = 66) or polyps with intraepithelial neoplasia (n = 70). In the per-patient analysis only 22.4 % of patients had no polypoid lesion, 27.6 % had at least one hyperplastic and 50.0 % had at least one adenomatous lesion. Sensitivity for adenomas of all size categories was calculated 55.7 % for CTC and 92.9 % for OC. This marked difference (both for the detection of individual lesions and the per-patient analyses) does not reach significance in the two-sided McNemar test.

CONCLUSIONS

There was a high prevalence of lesions with intraepithelial neoplasia in this screening group. OC had a higher sensitivity than CTC in the detection of lesions smaller than 10 mm.

The zinc-finger protein KCMF1 is overexpressed during pancreatic cancer development and downregulation of KCMF1 inhibits pancreatic cancer development in mice

Potassium channel modulatory factor 1 (KCMF1) was found upregulated in a differential screen in the metaplastic epithelium in the pancreas of transforming growth factor (TGF)-alpha transgenic mice. Expression analysis indicated broad overexpression in human cancer tissues. Therefore, we investigated the hypothesis that KCMF1 promotes metaplastic changes and tumor development. KCMF1 represents an evolutionarily highly conserved protein with a 95% identity between human and zebrafish. KCMF1 is expressed during embryonic development and in the majority of adult tissues investigated. Upregulation of nuclear KCMF1 expression is evident in preneoplastic lesions and in several epithelial malignancies, such as pancreatic cancer in mice and humans. In cell culture and in the chicken chorioallantoic membrane model, KCMF1 enhances proliferation, migration and invasion of HEK-293 and Panc1 cells. In crossbreeding experiments, KCMF1-knockdown gene trap mice showed a reduced number and size of premalignant lesions and absence of pancreatic cancer formation in TGF-alpha transgenic mice. This effect is related to the decreased expression of G1 to S cell-cycle regulators such as cyclin D and cyclin-dependent kinase (CDK) 4. Our data support the hypothesis that KCMF1 mediates pro-oncogenic functions in vitro and in vivo and downregulation of KCMF1 results in the inhibition of pancreatic cancer formation in mice. These effects are mediated through downregulation of cell-cycle control genes such as cyclin D and CDK4.

G(-2548)A leptin gene polymorphism in obese subjects is associated with serum leptin concentration and bone mass

INTRODUCTION

Clinical studies have shown either positive or in some other cases negative correlations between leptinemia and bone mineral density (BMD) or bone mineral content (BMC).

OBJECTIVES

The aim of the present study was to assess whether these discrepancies might be associated with the effect of G(-2548)A leptin or A326G and A668G leptin receptor gene polymorphisms on serum leptin concentrations or BMD and BMC.

PATIENTS AND METHODS

The study included 72 obese patients (39 women and 33 men, aged 46 +/-8.8 years; body mass index [BMI] >30 kg/m2). In all subjects, serum creatinine, glucose, lipids, leptin, and insulin were determined. Total fat mass (TFM), BMC, and BMD were assessed using dual energy X-ray absorptiometry (Lunar DPX-L).

RESULTS

No significant correlations were observed between body mass composition parameters (TFM, lean mass, BMC) or BMD in relation to genotypes. A positive correlation was found between serum leptin concentration and BMI. An inverse association was observed between leptin concentrations and BMC. Multiple regression analysis showed independent correlations of leptinemia with sex (P <0.001), TFM (P <0.000 001), BMC (P = 0.0001), and the presence of (-2548)A allele of the leptin gene (P <0.05). These parameters together accounted for 83% of variability in serum leptin concentrations.

CONCLUSIONS

In obese patients, serum leptin concentration shows an independent inverse correlation with BMD and male sex, but positively with TFM and the presence of -2548A allele of leptin gene. These parameters are responsible for 83% of leptin concentration variability. No correlations between the examined polymorphisms and BMC or BMD were found.

CD147 silencing inhibits lactate transport and reduces malignant potential of pancreatic cancer cells in in vivo and in vitro models

BACKGROUND

CD147 (basigin, EMMPRIN) is a multifunctional, highly conserved glycoprotein enriched in pancreatic ductal adenocarcinomas (PDACs) which is associated with poor prognosis in many malignancies. The role of CD147 in pancreatic cancer, however, remains elusive.

METHODS AND RESULTS

Silencing of CD147 by RNA interference (RNAi) reduced the proliferation rate of MiaPaCa2 and Panc1 cells. CD147 is required for the function and expression of the monocarboxylate transporters MCT1 and MCT4 that are expressed in human PDAC cells as demonstrated by real-time reverse transcription-PCR (RT-PCR) as well as immunohistology. MCT1 and MCT4 are the natural transporters of lactate, and MiaPaCa2 cells exhibited a high rate of lactate production, which is characteristic for the Warburg effect, an early hallmark of cancer that confers a significant growth advantage. Further induction of lactate production by sodium azide in MiaPaCa2 cells increased MCT1 as well as MCT4 expression. CD147 silencing inhibited the expression and function of MCT1 and MCT4 and resulted in an increased intracellular lactate concentration. Addition of exogenous lactate inhibited cancer cell growth in a dose-dependent fashion. In vivo, knock-down of CD147 in MiaPaCa2 cells by inducible short hairpin RNA (shRNA)-mediated CD147 silencing reduced invasiveness through the chorioallantoic membrane of chick embryos (CAM assay) and inhibited tumourigenicity in a xenograft model in nude mice.

CONCLUSION

The function of CD147 as an ancillary protein that is required to sustain the expression and function of MCT1 and MCT4 is involved in the association of CD147 expression with the malignant potential of pancreatic cancer cells exhibiting the Warburg effect.

Molecular determinants of the profibrogenic effects of endothelin-1 in pancreatic stellate cells

AIM: To gain molecular insights into the expression and functions of endothelin-1 (ET-1) in pancreatic stellate cells (PSC).

METHODS: PSCs were isolated from rat pancreas tissue, cultured, and stimulated with ET-1 or other extracellular mediators. Cell proliferation was assessed by measuring the incorporation of 5-bromo-2’-deoxyuridine into DNA and cell migration was studied in a transwell chamber assay. Gene expression at the level of mRNA was quantified by real-time polymerase chain reaction. Expression and phosphorylation of proteins were monitored by immunoblotting, applying an infrared imaging technology. ET-1 levels in cell culture supernatants were determined by an enzyme immunometric assay. To study DNA binding of individual transcription factors, electrophoretic mobility shift assays were performed.

RESULTS: Among several mediators tested, transforming growth factor-β1 and tumour necrosis factor-α displayed the strongest stimulatory effects on ET-1 secretion. The cytokines induced binding of Smad3 and NF-κB, respectively, to oligonucleotides derived from the ET-1 promoter, implicating both transcription factors in the induction of ET-1 gene expression. In accordance with previous studies, ET-1 was found to stimulate migration but not proliferation of PSC. Stimulation of ET-1 receptors led to the activation of two distinct mitogen-activated protein kinases, p38 and extracellular signal-regulated kinases (ERK)1/2, as well as the transcription factor activator protein-1. At the mRNA level, enhanced expression of the PSC activation marker, α-smooth muscle actin and two proinflammatory cytokines, interleukin (IL)-1β and IL-6, was observed.

CONCLUSION: This study provides novel lines of evidence for profibrogenic and proinflammatory actions of ET-1 in the pancreas, encouraging further studies with ET-1 inhibitors in chronic pancreatitis.

[Research funding of university medicine by the BMBF, DFG, and EU]

Public research funding is of growing importance for university medicine as a finance resource particularly in view of decreasing institutional budgets provided by the Federal States, as a serious stimulus for change in university medicine, and as an intra- and interuniversity research quality indicator, which is also used in the process of (re-)distributing institutional budgets. These three factors are largely determining the research in university medicine. The large funding institutions BMBF, DFG, EU have different programs and, thus, specific influence on the development of university medicine. The health research program of the BMBF focuses on clinical and patient oriented research, and gives incentives for the development of research structures of university medicine. The funding mechanism of the DFG is primarily demand oriented (bottom-up) and is focused on basic research. Nevertheless, the coordinated funding measures of the DFG are increasingly influencing the development of university medicine. The actual 7th framework program of the EU has a demand-orientated basic research program (ERC) as well as a broad structured program which also funds clinical research. With the recently invented instrument of joint programming the EU intends to influence the funding priorities of the member states.

Increased Duodeno-Gastro-Esophageal Reflux (DGER) in symptomatic GERD patients with a history of cholecystectomy

BACKGROUND

Duodenal-Gastro-Esophageal Reflux (DGER) represents an independent risk factor for the development of complicated Gastro-esophageal-reflux-disease (GERD) and Barrett's esophagus. Clinical and epidemiological data suggest a potential association between cholecystectomy (CCE) and augmented bile reflux.

METHODS

132 patients (67 women, 65 men, median age 55) with typical symptoms of GERD were enrolled in the study and divided in cholecystectomized (CCE-group: n = 107) and non- cholecystectomized (nCCE-group: n = 25) patients. Standardized clinical work-up of patients included combined esophageal 24 h pH-measurement and Bilitec 2000 esophageal manometry and upper endoscopy.

RESULTS

In the statistical analysis no differences between the cholecystectomized group (CCE-group, n = 25) and the patients without cholecystectomy (nCCE-group, n = 107) could be observed in quantity or quality of reflux symptoms. Furthermore, neither acid reflux nor severity of inflammation and frequency of Barrett's esophagus significantly differed between the nCCE and CCE-group. However, the percentage of patients with pathological DGER were significantly higher in the CCE-group as compared to the nCCE-group (76 vs. 55 %, p < 0.01). Moreover, the CCE-group revealed significant higher levels of pathological DGER compared to the nCCE-group (15.5 % +/- 14.1 vs. 8.6 % +/- 15.4; p < 0.05).

CONCLUSION

To conclude, our data provide first evidence of elevated DGER after CCE in patients with typical clinical symptoms of GERD using the Bilitec device. Both the frequency and the extent of DGER was significantly increased in the CCE-group. Prospective studies are urgently needed to elucidate the impact of CCE on DGER in patients with clinical symptoms of a reflux disease.

Effects of glucagon-like peptide-1 (GLP-1) in RINm5F insulinoma cells. Stimulation of insulin secretion, insulin content, and insulin receptor binding

Glucagon-like peptide-1 (GLP-1) is the major incretin hormone from the distal small intestine which stimulates basal and glucose-induced insulin secretion. Using the rat insulinoma cell line RINm5F (Gazdar et al. 1980) we investigated the effects of GLP-1 on insulin secretion, insulin content, and insulin receptor binding. During a 1 hour incubation, GLP-1 [1 nM] stimulated insulin secretion 2-fold (p < 0.01 vs controls). Incubating RINm5F for 24 h with GLP-1 [1 nM], a 1.6-fold higher cellular insulin content was observed (p < 0.01 vs controls). Moreover, GLP-1 induced a 2-fold higher capacity and a 15-fold higher affinity of 125I-insulin binding on the cell surface (p < 0.01 vs controls). Glucagon, known as a potent stimulator of insulin secretion, yielded a similar effect only in 1,000-fold higher concentrations, whereas the intracellular insulin content as well as insulin receptor binding was not increased. Taken together, in RINm5F insulinoma cells GLP-1 potently stimulates insulin secretion and insulin content, and improves insulin receptor binding.

Inotropic, chronotropic and dromotropic effects of prenalterol, a new cardiostimulant drug

Prenalterol (H 133/22) is an adrenergic beta-receptor stimulator which unlike isoproterenol is both orally active and has a long duration of action. The inotropic, chronotropic and dromotropic effects of prenalterol were investigated in pentobarbital anaesthetized dogs. Prenalterol was found to increase left ventricular maximum dP/dt in a dose-dependent manner up to a dose level of 50 micrograms/kg. Additional doses resulted in only small further increases in cardiac contractility. Electrophysiological studies were done to compare the effects of prenalterol and isoproterenol on sinus node and ventricular pacemaker function. Complete AV block was produced by electrocauterization of the His bundle. Prenalterol accelerated both ventricular and sinus node pacemakers at doses up to 50 micrograms/kg. The increase in ventricular rate was greater than the increase in sinus rate following supramaximal inotropic doses of prenalterol yet no ventricular extrasystoles were ever observed. Similar acceleration of the ventricular and sinus node pacemakers were observed by infusion of isoproterenol. Prenalterol and isoproterenol accelerated AV nodal conduction and ventricular conduction but had little effect upon His-Purkinje conduction. Sinus node reset time was abbreviated as was the functional and effective refractory periods of the atrium and AV nodes.

The Memory and Attention Test (MAT), an Adaptive, Computer-based Performance Test: Evaluation in Dementia, Mild Cognitive Impairment and Control Subjects

The Memory and Attention Test (MAT), a newly developed, adaptive, computer-based performance test was evaluated in a mixed group of patients with Alzheimer's dementia, subjects with mild cognitive impairment and control subjects at ages from 60 to 89 years.

By means of the MAT, working memory and short-term memory are assessed in the verbal, figural and episodic domains by means of six independent tests individually adjusted to the subjects level of performance on the basis of intermediate results. Sustained attention is also assessed.

For evaluation purposes, well established tests for the respective memory domains were applied. They were the Auditory Verbal and Learning Test (AVLT), the Benton Test, the delayed reproduction of the Taylor Figure, the subtests working memory and logical memory of the Wechsler Memory Scale (WMS) and the Alterskonzentrationstest (AKT), a test analogous to the d2 test, especially suited and standardized for older subjects. Acceptance of the MAT was assessed by means of a questionnaire developed for this purpose.

Computerized testing was commonly well accepted by the subjects. There were highly significant positive correlations between performance in the MAT domains and performance in the respective reference assessments. Thus, the MAT may be a useful diagnostic tool for the assessment of dementia patients. It may be applied for early diagnosis, assessment of progression of disease and demonstration of treatment effects, particularly for disease-modifying treatments in Alzheimer's disease. Standardization relating to age and and education as well as the provision of versions in various languages are under way.

Bones and Crohn's: estradiol deficiency in men with Crohn's disease is not associated with reduced bone mineral density

Background

Reduced bone mineral density (BMD) and osteoporosis are frequent in Crohn's disease (CD), but the underlying mechanisms are still not fully understood. Deficiency of sex steroids, especially estradiol (E2), is an established risk factor in postmenopausal osteoporosis.

Aim

To assess if hormonal deficiencies in male CD patients are frequent we investigated both, sex steroids, bone density and bone metabolism markers.

Methods

111 male CD patients underwent osteodensitometry (DXA) of the spine (L1–L4). Disease related data were recorded. Disease activity was estimated using Crohn's disease activity index (CDAI). Testosterone (T), dihydrotestosterone (DHT), estradiol (E2), sex hormone binding globulin (SHBG), Osteocalcin and carboxyterminal cross-linked telopeptids (ICTP) were measured in 111 patients and 99 age-matched controls.

Results

Patients had lower T, E2 and SHBG serum levels (p < 0.001) compared to age-matched controls. E2 deficiency was seen in 30 (27.0%) and T deficiency in 3 (2.7%) patients but only in 5 (5.1%) and 1 (1%) controls. Patients with E2 deficiency had significantly decreased T and DHT serum levels. Use of corticosteroids for 3 of 12 months was associated with lower E2 levels (p < 0.05). Patients with life-time steroids >10 g had lower BMD. 32 (28.8%) patients showed osteoporosis, 55 (49.5%) osteopenia and 24 (21.6%) had normal BMD. Patients with normal or decreased BMD showed no significant difference in their hormonal status. No correlation between markers of bone turnover and sex steroids could be found. ICTP was increased in CD patients (p < 0.001), and patients with osteoporosis had higher ICTP levels than those with normal BMD.

Conclusion

We found an altered hormonal status – i.e. E2 and, to a lesser extent T deficiency – in male CD patients but failed to show an association to bone density or markers of bone turnover. The role of E2 in the negative skeletal balance in males with CD, analogous to E2 deficiency in postmenopausal females, deserves further attention.