[Ductal adenocarcinoma and unusual differential diagnosis]. / Duktales Adenokarzinom und ungewöhnliche Differenzialdiagnosen.

Ductal pancreatic adenocarcinoma is by far the most common solid tumor of the pancreas. It has a very poor prognosis, especially in the more advanced stages which are no longer locally confined. Due to mostly unspecific symptoms, imaging is key in the diagnostic process. Because of the widespread use of imaging techniques, incidental findings are to a greater extent discovered in the pancreas, which subsequently entail further work-up. Ductal pancreatic adenocarcinoma can be mimicked by a large number of different lesions, such as anatomical variants, peripancreatic structures and tumors, rarer primary solid pancreatic tumors, cystic tumors, metastases or different variants of pancreatitis. Additionally, a number of precursor lesions can be differentiated. The correct classification is thus important as an early diagnosis of ductal pancreatic adenocarcinoma is relevant for the prognosis and because the possibly avoidable treatment is very invasive. All major imaging techniques are principally suitable for pancreatic imaging. In addition to sonography of the abdomen, usually the baseline diagnostic tool, computed tomography (CT) with its superior spatial resolution, magnetic resonance imaging (MRI) with its good soft tissue differentiation capabilities, possibly in combination with MR cholangiopancreatography (MRCP), endosonography with its extraordinary spatial resolution, conceivably with additional endoscopic retrograde CP or the option of direct biopsy and finally positron emission tomography CT (PET-CT) as a molecular imaging tool are all particularly useful modalities. The various techniques all have its advantages and disadvantages; depending on the individual situation they may need to be combined.

Bioacumulation of cyanotoxins in Hypophthalmichthys molitrix (silver carp) in Paranoá Lake, Brasilia-DF, Brazil.

Three individuals of silver carp (Hypophthalmichthys molitrix) were collected biweekly from Paranoá Lake (DF, Brazil) for analysis of microcystin (MC) concentrations in their muscle and liver tissue. Analysis by high performance liquid chromatography and mass spectrometry revealed MC masses and fragmentation patterns that were identified as MC-LR (995.04 m/z), MC-LA (909.01 m/z) and an unknown MC (987.07 m/z). Concentrations were calculated as MC-LR equivalents using a calibration curve prepared with a standard of MC-LR. May/06 was the month with the highest MC-LR equivalent concentrations in muscle and liver (3.83 ± 2.78, and 12.94 ± 10.51 µg g(-1), respectively). Our results show that during the drought months (April-September), consumption of fish with these MC concentrations would result in exposure to MCs that greatly exceed the World Health Organization's recommended tolerable daily intake limit of 0.04 µg MC kg(-1) body weight.

Cassava diversity in Brazil: the case of carotenoid-rich landraces.

In Brazil, the center of cassava origin, cassava landraces have acquired through their domestication a large diversity in relation to many economic traits such as high content of carotenoids and excellent palatability among other characters. One of these clones, which has been grown by indigenous Brazilian farmers and is now being maintained in the University of Brasília gene bank, showed a high level of lycopene content (5 mg/kg viz. a viz. zero in common cultivars, and 12-20 mg/kg in tomato, a lycopene-rich vegetable). A second landrace called UnB 400 had a high content of beta-carotene, which reached 4 mg/kg.

Prenatal radiation exposure: dose calculation.

The unborn child requires special protection. In this context, the indication for an X-ray examination is to be checked critically. If thereupon radiation of the lower abdomen including the uterus cannot be avoided, the examination should be postponed until the end of pregnancy or alternative examination techniques should be considered. Under certain circumstances, either accidental or in unavoidable cases after a thorough risk assessment, radiation exposure of the unborn may take place. In some of these cases an expert radiation hygiene consultation may be required. This consultation should comprise the expected risks for the unborn while not perturbing the mother or the involved medical staff. For the risk assessment in case of an in-utero x-ray exposition deterministic damages with a defined threshold dose are distinguished from stochastic damages without a definable threshold dose. The occurrence of deterministic damages depends on the dose and the developmental stage of the unborn at the time of radiation. To calculate the risks of an in-utero radiation exposure a three-stage concept is commonly applied. Depending on the amount of radiation, the radiation dose is either estimated, roughly calculated using standard tables or, in critical cases, accurately calculated based on the individual event. The complexity of the calculation thereby increases from stage to stage. An estimation based on stage one is easily feasible whereas calculations based on stages two and especially three are more complex and often necessitate execution by specialists. This article demonstrates in detail the risks for the unborn child pertaining to its developmental phase and explains the three-stage concept as an evaluation scheme. It should be noted, that all risk estimations are subject to considerable uncertainties. • Radiation exposure of the unborn child can result in both deterministic as well as stochastic damage und hitherto should be avoided or reduced to a minimum.• In case of radiation a suitable hygiene consultation may be necessary.• For risk assessment a three-stage concept is applied, which, depending on the radiation exposure, estimates or calculates the dose for the unborn child.• The radiologist plays a crucial role as a competent advisor and provider of reliable expert information. Citation Format: • Scharwächter C, Röser A, Schwartz CA et al. Prenatal Radiation Exposure: Dose Calculation. Fortschr Röntgenstr 2015; 187: 338 - 346.

The relationship between pre-harvest stress and the carcass characteristics of beef heifers that qualified for kosher designation.

Differences in pre-harvest stress measurements and carcass characteristics between kosher and not-qualified-as-kosher cattle were evaluated. Finished heifers (n=157) were slaughtered by a shochet while held in an upright position using Glatt slaughter procedures. Stress measurements were collected prior to slaughter. Carcass data were collected, and 3.8-cm thick samples were taken from the loin at the 13th rib. Steaks from each sample were evaluated for mechanical tenderness and simulated retail display. Cattle with shorter times from gate to exsanguination and lower vocalization scores were more likely (P < 0.01) to qualify as kosher. Kosher carcasses had larger (P = 0.02) ribeye areas and higher (P < 0.0001) Warner-Bratzler shear values. At each day of simulated retail display, kosher steaks had lower (P < 0.05) L*, a*, and b* values. These data suggest that body composition and pre-harvest stress affect the likelihood of a beef animal qualifying as kosher and quality differences exist between kosher and non-kosher steaks.

Age-related changes in the protein concentration gradient and the crystallin polypeptides of the lens.

With the use of a freeze-sectioning technique, the existence of a centripetal protein gradient in the rabbit lens is demonstrated. The steepness of this gradient (the difference in the protein concentration between periphery and the center) varies with age: it increases from a value of 40% in 6- to 8-month-old lenses to 60% by the age of 4 to 5 years and then begins to decline at an average rate of about 5% per year, reaching a value below 40% in 9-year-old lenses. The decline in protein concentration gradient is reciprocated by a gain in the water content. Electrophoretic evidence shows that the decline in the protein gradient is preceded and accompanied by postsynthetic modification of lens crystallin polypeptides. Modifications result in the formation of crosslinked material that stays on the top of sodium dodecyl sulfate gels and of degraded polypeptides with molecular weights below 20,000 daltons. It is hypothesized that the protein gradient comes about probably because lens crystallins are capable of making extensive surface contacts to produce a tightly packed matrix. As the lens ages, post-synthetic modifications and hydrolytic breakdown produce a gradual disorganization in these structural proteins. Local or general disorganization will allow water to fill the gaps and produce hydration, which could predispose the lens to opacity formation.

Enterococcal eschars in cutaneous T-cell lymphoma tumors: a distinct clinical entity.

Cutaneous T-cell lymphomas (CTCL) are extranodal non-Hodgkin's T-cell lymphomas that present in the skin, the most common form being mycosis fungoides. The progression of disease is associated with acquired immunodeficiency and increased susceptibility to infections. Ten CTCL patients presented with dark brown to black eschars overlying ulcerated tumors that cultured positive for Enterococcus and healed with appropriate antibiotic therapy. Enterococcal infections in CTCL tumors may be recognized as a distinct clinical entity requiring specific intervention.

A tetrodotoxin-like substance found in the Brazilian frog Brachycephalus ephippium.

A tetrodotoxin-like substance, denoted ephippiotoxin, was obtained from the tissue of Brachycephalus ephippium, a small pumpkin-coloured frog collected in the Atlantic Forest of the southeast region of Brazil. Ephippiotoxin is a dialyzable substance soluble in water, methanol and ethanol, but insoluble in organic solvents such as chloroform and other apolar solvents. After treatment with active charcoal (Norit-A) and purification with ion-exchange Amberlite IRC-50 resin (NH4 + form), a freeze-dried residue was obtained, with a toxicity of c. 117 micrograms/kg (mice, i.p.). Ephippiotoxin showed the same mobility as crystalline tetrodotoxin (Sankyo) when submitted to thin-layer chromatography (silica gel G) using seven different solvent systems. White mice (20 +/- 1 g) injected i.p. with either B. ephippium tissue extracts or semi-purified toxin showed partial paralysis of the hind limbs, lethargy, altered breathing rhythm and clonic convulsions. Death occurred within 1.5-30 min after injection, depending on the dose. Ephippiotoxin induced atrioventricular diastolic blockade in the toad heart. It also inhibited the response of toad striated muscle to direct and indirect electric stimulation and blocked the compound action potential of isolated frog sciatic nerve.

Indirect cardiotoxic activity of the caecilian Siphonops paulensis (Gymnophiona, Amphibia) skin secretion.

The skin secretion of the caecilian S. paulensis has an indirect cardiotoxic effect. It induces a rapid blockage of electrical activity and subsequent diastolic arrest on in situ toad heart preparations. This action is not blocked by atropine and is therefore not mediated through a cholinergic mechanism. In addition, S. paulensis skin secretion is ineffective in inducing any response in isolated perfused toad heart assay, in the spontaneously beating isolated toad atria or in the electrically driven toad ventricle strip. These results, and the observation that S. paulensis skin secretion exhibits an hemolytic activity ([Schwartz, E. F., Schwartz, C. A., Sebben, A., Mendes E. G. (1997) Cardiotoxic and hemolytic activities on the caecilian Siphonops paulensis skin secretion. J. Venom. Anim. Toxins 3(1), 190]), suggest that the skin secretion cardiotoxicity could be mediated through an endogenous agent. The cardiotoxic action of S. paulensis skin secretion was investigated in isolated toad cardiac tissues in the presence of toad red blood cells (TRBC). In both atria and ventricle it evoked the same responses observed in the in situ heart. The potassium concentrations of the suspending media, as determined by atomic absorption spectroscopy were 9.5 and 11.7 times greater, respectively, in the presence of TRBC than in its absence. Given that increased levels of potassium also showed a negative inotropic effect in the isolated ventricle strip, the action of the skin secretion was attributed to the hemolytic activity, which causesan increase in K+ concentration of the medium.

Utilization of O-phthalaldehyde-sulphuric acid as a spray reagent in thin-layer chromatographic detection of some indolealkylamines and application to cutaneous secretion extracts of toad species.

An expansion of the utilisation of o-phthalaldehyde in sulphuric acid medium as spray reagent was carried out when tryptophan and some tryptophan-derived indole alkylamines such as tryptamine, serotonin, bufotenine, dehydrobufotenine and bufotenidine were examined by thin-layer chromatography. Rf-values and limits of detection ranging from 20 (serotonin) to 100 (dehydrobufotenine) ng per spot were found. Application of this reagent for the detection of some of these compounds was carried out, using either methanolic extracts or column chromatographic fractions of the skin secretion of the toads Bufo ictericus and Odontophrynus cultripes.

Purification of a heat-stable beta-crystallin polypeptide of the bovine lens.

A major polypeptide component of bovine lens beta-crystallins has been found to be heat stable. This property is utilized for purification of this polypeptide on a preparative scale. A homogenate of lens crystallins buffered at pH of 7.3 with 0.95 M Tris containing 1mM DTT and 1mM EDTA is heated to 97-99 degrees C for 3-5 min. Denatured proteins are removed and the clear supernatant is lyophilized. The lyophilized material mostly consists of the major polypeptide component common to the beta-crystallins with minor quantities of some low molecular weight polypeptides. These contaminants can be removed by preparative polyacrylamide gel electrophoresis. Amino acid analysis, electrophoretic mobility and chromatographic behavior of the purified polypeptide indicate that it is similar to the beta Bp polypeptide. Antibodies raised against this polypeptide react with all beta-crystallins but not with the alpha-or gamma crystallins.

The effects of UV-B irradiation on the corneal endothelium.

Rabbit eyes, in vivo and in vitro, were exposed to UV-B irradiation at 300 nm, from a mercury arc lamp with an 11 nm bandpass filter. Radiant exposure ranged from 0.1 J/cm2 to 0.5 J/cm2. In vivo, swelling of the cornea resulted over a 12 to 40 hr period, the extent and duration being directly related to exposure. Recovery of normal thickness was complete within four days. Corneas removed at 18 hr after exposure recovered normal thickness during a five hour perfusion period, except for those most heavily exposed. When removed at 42 hr post exposure all corneas thinned to almost normal thickness. SEM showed the endothelial cells of exposed eyes to have either exaggerated villi on the surface and a disorganized mosaic or, after higher exposures, to be devoid of villi and have loose, flap like cell borders and large "blebs." After exposure of isolated corneas mounted for perfusion, swelling again ensued and similar changes were observed in the appearance of the cells, except that "blebs" were not found. No significant changes were observed in the metabolic components ATP, ascorbate and glutathione, nor was there any indication of lipid peroxidation. At higher in vivo exposures, the aqueous humor did show a decrease in ascorbate concentration and an increase in protein content, which probably result from a breakdown of the blood-aqueous barrier. UV-B irradiation may cause or promote changes in the endothelium associated with aging, but the one time radiant exposures of the magnitude used in this study, appear to have no severe or permanently toxic effects.

Interactions of ascorbate and H2O2: implications for in vitro studies of lens and cornea.

The interaction of ascorbate, hydrogen peroxide and oxygen has been examined in order to understand the equilibrium between these compounds that exists in the aqueous humor of the eye and their influence on function of the corneal endothelium. Ascorbate was found to promote corneal swelling when isolated corneas were perfused with a medium lacking glucose. This was found to be due to the rapid oxidation of ascorbate in the medium, yielding H2O2 which is toxic to the endothelial cells. In the absence of oxygen, or if EDTA was added to the medium, no H2O2 was produced from ascorbate, but ascorbate reacted with any pre-existing H2O2. Oxidation of ascorbate in the aqueous humor is limited by the presence of glutathione (and, possibly, other compounds) and no significant increase in H2O2 concentration occurs on standing in air. Nevertheless, the concentration of H2O2 in the aqueous is directly dependent on the concentration of ascorbate secreted in the aqueous humor. Therefore, there must be a dynamic equilibrium in this fluid between ascorbate, H2O2 and oxygen, and it may be modulated by glutathione. Each of these substances is important in redox reactions, including free-radical production or scavenging. Consequently, when studying the effects on corneal or lenticular function of other agents which cause or relieve oxidant stress, it is critical that the modifying effects of ascorbate and H2O2, as they occur in vivo, be considered. A perfusion system is described which permits an approximation in vitro of stable concentrations of ascorbate, H2O2, GSH and O2 similar to those found in the aqueous humor.

Establishment and characterization of a lens epithelial cell line from an eight year old rabbit.

Although information is available on the in vitro properties of lens epithelia of young adult animals from several species, few, if any reports document the conditions required for the initiation and long-term culture of lens epithelium from animals beyond their medium life-span. We report here on the conditions required for the culture of lens cells from an 8 year old rabbit. New Zealand White rabbits have a median life-span of approximately 7 years. Primary culture was initiated in MEM supplemented with 10% rabbit serum. Cells reached confluency within 25 days, responded to serum in a dose dependent manner and had an average doubling time of 23 h during the logarithmic growth phase. Cells increased in number in a dose dependent manner when insulin, insulin growth factor, epidermal growth factor (EGF), or fibroblast growth factor (FGF) was added to the culture medium. Thus, lens epithelia from this very old rabbit retained the ability to respond to highly purified growth factors. Cells exposed to a medium supplemented with insulin, EGF and FGF showed a five-fold increase in number at day 7 of culture, a value exceeding that brought about by the individual growth factors. An examination of chromosomal preparations indicated that the cells were aneuploid. Whether the aneuploidy was acquired in vitro or is a normal adjunct of aging in the lens in vivo is unknown. Proteins extracted from this line contained polypeptides that migrated to the position of and had apparent molecular weights of lens proteins.

Skin secretion of Siphonops paulensis (Gymnophiona, Amphibia) forms voltage-dependent ionic channels in lipid membranes.

The effect of the skin secretion of the amphibian Siphonops paulensis was investigated by monitoring the changes in conductance of an artificial planar lipid bilayer. Skin secretion was obtained by exposure of the animals to ether-saturated air, and then rinsing the animals with distilled water. Artificial lipid bilayers were obtained by spreading a solution of azolectin over an aperture of a Delrin cup inserted into a cut-away polyvinyl chloride block. In 9 of 12 experiments, the addition of the skin secretion to lipid bilayers displayed voltage-dependent channels with average unitary conductance of 258 +/- 41.67 pS, rather than nonspecific changes in bilayer conductance. These channels were not sensitive to 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid or tetraethylammonium ion, but the experimental protocol used does not permit us to specify their characteristics.

Prediction of troponin-T degradation using color image texture features in 10d aged beef longissimus steaks.

The objective was to use digital color image texture features to predict troponin-T degradation in beef. Image texture features, including 88 gray level co-occurrence texture features, 81 two-dimension fast Fourier transformation texture features, and 48 Gabor wavelet filter texture features, were extracted from color images of beef strip steaks (longissimus dorsi, n = 102) aged for 10d obtained using a digital camera and additional lighting. Steaks were designated degraded or not-degraded based on troponin-T degradation determined on d 3 and d 10 postmortem by immunoblotting. Statistical analysis (STEPWISE regression model) and artificial neural network (support vector machine model, SVM) methods were designed to classify protein degradation. The d 3 and d 10 STEPWISE models were 94% and 86% accurate, respectively, while the d 3 and d 10 SVM models were 63% and 71%, respectively, in predicting protein degradation in aged meat. STEPWISE and SVM models based on image texture features show potential to predict troponin-T degradation in meat.

[Intussusception after Billroth II operation fifty years ago - an unusual cause for ileus]. / Invagination nach Billroth-II-Operation vor 50 Jahren - eine ungewöhnliche Ursache für einen Ileus.

HISTORY: A 77-year-old woman presented with occasional vomiting of hematin but no further complaints. 50 years ago a partial gastrectomy after Billroth II had been performed due to a gastric ulcer. INVESTIGATIONS: The physical examination revealed no pathologic findings. All laboratory values, including hemoglobin (HB), were in normal range. The gastroscopic examination showed traces of hematin in the stomach and in the efferent and afferent loop.  The Braun anastomosis could not be delineated. No other pathologic findings were noted. TREATMENT AND COURSE: At the request of the patient additional regular controls of hemoglobin were planned on an outpatient basis. In case of hemoglobin decrease, further treatment should be arranged. Two days after discharge the patient was presented with sudden massive abdominal pain and vomiting. Clinical examination confirmed the assumption of mechanical ileus. An emergency abdominal CT showed an intussusception of a small bowel loop into the Braun anastomosis as the ileus trigger. A laparotomy was carried out immediately after the CT. Because of severe ischemic damage of the intussuscepted loop, an "en bloc" resection of the loop including the Braun anastomosis including reanastomosis had to be carried out. CONCLUSION: Intussusception is primarily a childhood disease, occurring in adults only in about 5% of cases. Postoperative intussusception is a rare complication after gastric surgery.Especially because of its exceptionality the diagnosis of intussusception in adulthood can be difficult. Crucial herein is to have intussusception in mind in the differential diagnostic pathway of a post gastric surgery ileus.

[Experimental early detection of acute mesenteric ischemia with functional MRI (DWI) and parallel imaging]. / Experimentelle Frühdiagnostik der akuten mesenterialen Ischämie mittels diffusionsgewichteter MRT (DWI) und paralleler Bildgebung.

PURPOSE: To evaluate the feasibility of diagnosing in statu nascendi mesenteric ischemia using diffusion-weighted imaging (DWI) in a porcine model. All experiments were approved by the animal care committee at the district administration. MATERIALS AND METHODS: Mesenteric blood supply was studied in ten healthy female pigs (weight ~50 kg) with artificially induced mesenteric ischemia. In the DSA technique a branch of the superior mesenteric artery was embolized with tissue glue or small particles. DWI was performed using a 1.5 T MR scanner before embolization and 30 and 60 minutes after embolization using a 32-channel receiver coil. ADC maps were calculated for all animals. The findings were correlated to angiographic and autoptic findings. The image quality of DWI was assessed by means of SNR measurements and diagnostic impact by CNR measurements. RESULTS: Embolization of the mesenteric branches was technically successful in all cases. DWI of the bowel was feasible with the applied sequences. In all animals, DWI displayed distinct cytotoxic edema as the earliest sign of ischemia thirty minutes after induction of ischemia. Furthermore, DWI yielded a distinct reduction in the water diffusion coefficient in all animals. Variance analysis showed good correlation between CNR measurements and infarction areas. Autoptic findings could confirm the detected infarction areas by DWI. CONCLUSION: DWI using parallel imaging techniques is feasible for the early detection of acute mesenteric ischemia. The presented DWI results offer encouraging prospects regarding more rapid disease diagnosis.

Predicting beef tenderness using color and multispectral image texture features.

The objective of this study was to investigate the usefulness of raw meat surface characteristics (texture) in predicting cooked beef tenderness. Color and multispectral texture features, including 4 different wavelengths and 217 image texture features, were extracted from 2 laboratory-based multispectral camera imaging systems. Steaks were segregated into tough and tender classification groups based on Warner-Bratzler shear force. The texture features were submitted to STEPWISE multiple regression and support vector machine (SVM) analyses to establish prediction models for beef tenderness. A subsample (80%) of tender or tough classified steaks were used to train models which were then validated on the remaining (20%) test steaks. For color images, the SVM model correctly identified tender steaks with 100% accurately while the STEPWISE equation identified 94.9% of the tender steaks correctly. For multispectral images, the SVM model predicted 91% and STEPWISE predicted 87% average accuracy of beef tender.