Long-term exposure of immortalized keratinocytes to arsenic induces EMT, impairs differentiation in organotypic skin models and mimics aspects of human skin derangements.

Arsenic is one of the most important human carcinogens and environmental pollutants. However, the evaluation of the underlying carcinogenic mechanisms is challenging due to the lack of suitable in vivo and in vitro models, as distinct interspecies differences in arsenic metabolism exist. Thus, it is of high interest to develop new experimental models of arsenic-induced skin tumorigenesis in humans. Consequently, aim of this study was to establish an advanced 3D model for the investigation of arsenic-induced skin derangements, namely skin equivalents, built from immortalized human keratinocytes (NHEK/SVTERT3-5). In contrast to spontaneously immortalized HACAT cells, NHEK/SVTERT3-5 cells more closely resembled the differentiation pattern of primary keratinocytes. With regard to arsenic, our results showed that while our new cell model was widely unaffected by short-time treatment (72 h) with low, non-toxic doses of ATO (0.05-0.25 µM), chronic exposure (6 months) resulted in distinct changes of several cell characteristics. Thus, we observed an increase in the G2 fraction of the cell cycle accompanied by increased nucleus size and uneven tubulin distribution. Moreover, cells showed strong signs of de-differentiation and upregulation of several epithelial-to-mesenchymal transition markers. In line with these effects, chronic contact to arsenic resulted in impaired skin-forming capacities as well as localization of ki67-positive (proliferating) cells at the upper layers of the epidermis; a condition termed Bowen's disease. Finally, chronically arsenic-exposed cells were characterized by an increased tumorigenicity in SCID mice. Taken together, our study presents a new model system for the investigation of mechanisms underlying the tumor-promoting effects of chronic arsenic exposure.

Phase I metabolites of mephedrone display biological activity as substrates at monoamine transporters.

BACKGROUND AND PURPOSE: 4-Methyl-N-methylcathinone (mephedrone) is a synthetic stimulant that acts as a substrate-type releaser at transporters for dopamine (DAT), noradrenaline (NET) and 5-HT (SERT). Upon systemic administration, mephedrone is metabolized to several phase I compounds: the N-demethylated metabolite, 4-methylcathinone (nor-mephedrone); the ring-hydroxylated metabolite, 4-hydroxytolylmephedrone (4-OH-mephedrone); and the reduced keto-metabolite, dihydromephedrone. EXPERIMENTAL APPROACH: We used in vitro assays to compare the effects of mephedrone and synthetically prepared metabolites on transporter-mediated uptake and release in HEK293 cells expressing human monoamine transporters and in rat brain synaptosomes. In vivo microdialysis was employed to examine the effects of i.v. metabolite injection (1 and 3 mg·kg(-1) ) on extracellular dopamine and 5-HT levels in rat nucleus accumbens. KEY RESULTS: In cells expressing transporters, mephedrone and its metabolites inhibited uptake, although dihydromephedrone was weak overall. In cells and synaptosomes, nor-mephedrone and 4-OH-mephedrone served as transportable substrates, inducing release via monoamine transporters. When administered to rats, mephedrone and nor-mephedrone produced elevations in extracellular dopamine and 5-HT, whereas 4-OH-mephedrone did not. Mephedrone and nor-mephedrone, but not 4-OH-mephedrone, induced locomotor activity. CONCLUSIONS AND IMPLICATIONS: Our results demonstrate that phase I metabolites of mephedrone are transporter substrates (i.e. releasers) at DAT, NET and SERT, but dihydromephedrone is weak in this regard. When administered in vivo, nor-mephedrone increases extracellular dopamine and 5-HT in the brain whereas 4-OH-mephedrone does not, suggesting the latter metabolite does not penetrate the blood-brain barrier. Future studies should examine the pharmacokinetics of nor-mephedrone to determine its possible contribution to the in vivo effects produced by mephedrone.

Complications associated with the use of Port-a-Caths in patients with malignant or haematological disease: a single-centre prospective analysis.

Totally implantable central venous catheters are widely used in the management of patients with haematological or malignant disease. This paper investigates device-related complications and compares it with the literature. A total of 143 Port-a-Caths (PaCs) were implanted in 140 patients at a single centre during 2004 and followed until March 2005. Indication for implantation was mainly administration of chemotherapy. High standards of care were applied through intensive training of staff. Complications were registered prospectively and cross-checked with the medical records at the end of the observational period. The ports were in place for a total of 29 107 days (mean 204, range 3-443 days per port). A total of 25 complications were recorded. These included 13 infections [9.1% with 5 cutaneous (3.5%) and 8 systemic (5.6%) infections], one deep vein thrombosis (0.7%). In 6 patients (4.2%) the device had to be removed because of complications. No device-related death was observed. The use of totally implantable central venous catheters for treating haemoto-oncological patients is safe. The need for device removal due to complications was particularly low in this analysis as compared with the literature.

[Obstructive jaundice and acute pancreatitis due to an obstruction of the afferent loop after billroth-II-resection]. / Verschlussikterus und akute Pankreatitis durch Obstruktion der zuführenden Schlinge nach Billroth-II-Resektion.

An obstruction of the afferent loop after Billroth-II-resection is an extremely rare late complication of this procedure. We report on a 76-year-old female patient with a history of Billroth-II-resection 11 years ago who was admitted due to acute pancreatitis and obstructive jaundice. Abdominal sonography lead to the suspicion of a dilated afferent loop, which could be proven by means of magnetic resonance imaging. A tumorous lesion as cause of the obstructive jaundice was not detectable. Intraoperatively a volvulus of the small intestine and strangling adhesions near the Braun's anastomosis were seen, causing the obstruction of the afferent loop. Following reposition of the small intestine and adhesiolysis the patient gained a quick relief of symptoms and the jaundice disappeared completely.

[Analysis of referral diagnoses of patients with normal coronary angiogram]. / Analyse der Zuweisungsdiagnosen bei Patienten mit unauffälligem Koronarangiogramm.

BACKGROUND AND AIMS: Angiography permits an evaluation of the morphology of the coronary artery, stratification of risk and optimal therapeutic management in patients with suspected coronary artery disease (CAD). The sophisticated apparatus, cost and invasiveness of the procedure necessitate well-considered application of this method. In spite of an exact documentation of the patient's medical history and careful establishment of the indication, the results of angiography are often normal. Therefore, it appears important to analyse the referral diagnoses in patients with normal coronary angiograms. PATIENTS AND METHODS: We studied 1000 consecutive patients (625 men, 375 women, mean age 63.1 years) who underwent coronary angiography at our institution from January to May 1998. All patients were included in the retrospective analysis of the referral diagnoses. RESULTS: 875 patients (554 men, 321 women) were referred due to suspected CAD; 173 of these had normal angiographic findings (20%; 73 men, 100 women; mean age 58.4 years). The referral diagnoses were as follows: unstable angina in 62 patients (36%), stable angina in 40 patients (23%), chest pain and pathological findings of non-invasive testing in 32 patients (19%), atypical chest pain in 25 patients (14%), previous myocardial infarction and multiple risk factors in 7 patients each (4% each). Gender-related differences were remarkable. Only 73 of the 554 referred men (13%) had normal angiographic findings, whereas in women the rate of normal results was more than twofold higher, i.e. 100 of the 321 referred women (31%) had normal angiographic findings (p < 0.01). CONCLUSIONS: Among 875 patients referred to our catheter laboratory for coronary angiography due to suspected CAD, normal angiographic results were documented in 20%. The high frequency of the referral diagnosis 'unstable angina' and 'pathological result of noninvasive testing' was as remarkable as the high proportion of women among patients with normal findings.

[Clinical presentation and coronary angiographic results in unstable angina pectoris]. / Klinische Präsentation und koronarangiographische Befunde bei instabiler Angina pectoris.

The syndrome "unstable angina" (UA) covers a broad spectrum of patients. In this study we tried to determine the relationship between the severity of UA and angiographic findings. We evaluated 1000 consecutive patients undergoing coronary angiography. Those with the clinical diagnosis "UA" were included in the study. In a retrospective analysis of their records we categorized them, using the Braunwald-classification for determination of the severity of the disease. 352 patients were include, 209 men and 143 women, the mean age was 65 years. 47% met Braunwald-Class I, 26% Class II and 27% Class III. Coronary single-vessel disease was present in 29%, two-vessel disease in 20%, three-vessel disease in 25%, normal coronaries in 13% and coronary atherosclerosis without critical narrowing in 13%. Left ventricular function was preserved in 72%, mild systolic dysfunction was found in 10%, moderate in 13% and severe in 5%. There was no overall correlation between clinical presentation (Braunwald-Classes) and angiographic findings. Women showed a similar distribution of Braunwald-Classes, but significantly more coronary arteries without critical obstruction. In patients with reduced systolic function the percentage of multi-vessel disease was significantly higher, the percentage without relevant coronary artery narrowing was significantly lower. 1) The lack of overall correlation between clinical presentation and angiographic findings supports the importance of coronary angiography in the evaluation of patients with UA. 2) The assessment of women with chest pain is more difficult than of men with regard to coronary heart disease. 3) UA in patients with impaired left ventricular function is a predictor of severe coronary artery disease.

[Benefits and limits of sonography of the masseter muscle]. / Möglichkeiten und Grenzen der sonographischen Diagnostik des M. masseter.

A sonographic method for diagnosis, follow-up and quantification of normal and hypertrophied masseter muscles is presented. This technique lends itself to diagnosis of macroscopic structural alterations of the muscle as well as tumors in the vicinity. Functional or microscopic tissue changes like trigger points in myofacial pain-dysfunction syndrome cannot be detected sonographically.

Human cryptosporidiosis associated with an epizootic in calves.

An outbreak of human cryptosporidiosis occurred among previously healthy persons in a veterinary medical teaching hospital. Human illness began after admission of calves from a farm which had been experiencing an epizootic of neonatal diarrhea due to Cryptosporidium. The clinical syndrome in humans was characterized by watery diarrhea, abdominal cramping, flatulence, and headache. Cryptosporidiosis was confirmed by zinc sulfate flotation of fecal specimens in four persons, three of whom had been responsible for the care and treatment of infected calves. A fourth patient had washed her husband's soiled clothing and appeared to have been infected indirectly through fomite contamination. Among 112 persons surveyed, 26 (23.2 percent) had a diarrheal illness during the outbreak and nine met the case definition of a diarrheal illness lasting at least three days. These persons were more likely to have had contact with a calf with diarrhea than were 52 referents who did not become ill during the outbreak.