Lipomatous pancreas facilitates late onset of renal cell carcinoma metastases.

BACKGROUND: Late metastasizing into pancreatic tissue is a special hallmark of renal cell carcinomas (RCC). A very low prevalence leads to scarce data about therapy, prognosis and spreading pathways. The aim of the study was to analyze whether a high fat content in the pancreas facilitates RCC metastases formation. A model for density measurement of pancreatic tissue has been developed and evaluated. Pancreatic fat content was measured comparing Hounsfield units (HU) of CT scans. METHODS: In a consecutive single centre retrospective database of 3600 patients with pancreatic resections, only 12 patients (0.3%) cases of RCC metastases in the pancreas were found. HU were measured in 3 pancreatic regions: head, body and tail in patients' CT scans. HU values were compared to a control population and results aligned with recent literature. RESULTS: We revealed a prevalence of pancreatic metastases of RCC in 0.3% of cases. The formation of RCC in the pancreas occurred within 14 ± 5.6 years after initial diagnosis of RCC. 83.3% of the patients were alive after a follow-up period of up to 48 months. Clinical data analysis revealed an affinity for metastatic formation to lipomatous pancreas. This could be objectivized by HU analysis in CT scans. CONCLUSION: Pancreatic metastases occur late after the first diagnosis of renal carcinoma and show an affinity for lipomatous pancreatic tissues. Due to its rarity in occurrence, multicentric studies are highly recommended to further analyze this correlation between fatty pancreas and RCC.

Perturbations of radiation field caused by titanium dental implants in pencil proton beam therapy.

The aim of this study was to investigate the absorbed dose and the linear energy transfer (LET) of a scanning proton pencil beam at the Proton Therapy Center Czech, applied to phantoms containing metal implants. We investigated two different phantoms composed of commonly used metals with a known chemical composition. Two rectangular phantoms consisted of water-equivalent environment material with a 65 mm thickness surrounding the 2, 5, 10 and 15 mm inserts of grade-2 and grade-5 Titanium. Track-etched detectors (TEDs) were placed behind the phantoms to gather the data. The measured LET spectra behind the implants were compared with Monte Carlo simulations using the Geant4 toolkit, version 10.03.p01. The simulations were used to provide additional information regarding the contribution of each type of particles to the LET spectra (protons, alpha particles, deuteron, neutrons, photons, and electrons) and to estimate the LET spectra above the TED's detection threshold. We used two different beam energies to study the most pertinent irradiation scenarios, one in the Bragg curve plateau and one at the maximum. The measurement of the LET spectra behind phantoms irradiated with a proton beam in the plateau region of the Bragg curve led to the detection of numerous particles with a very high LET. Lateral dose enhancement at the border between implants and the plastic material was detected when the phantoms were exposed to a proton beam and the data were recorded in the Bragg peak maximum. In this area, the dose increased 13 times for grade-2 Ti and 12 times for grade-5 Ti. The performed experimental study highlights the effect of dental implants on the LET spectra and absorbed dose when a proton pencil beam is crossing high-density titanium.

Diagnostic double strike in the emergency room - two cases of complete pancreatic ruptures due to bicycle handlebar injuries on two consecutive days.

BACKGROUND: Pancreatic injuries are rare in cases of blunt abdominal trauma and therefore easily misdiagnosed at time of hospital admission. They are associated with a significantly elevated morbidity and lethality. Bicycle handlebar injuries are the most common cause of pancreatic trauma in children and adolescents. CASE PRESENTATION: We report two cases of a 23-year-old Caucasian woman and a 15-year-old Caucasian boy who presented to our clinic with a similar history of a bicycle accident on 2 consecutive days. Both suffered from a fall from a bicycle with bicycle handlebar injury 4 and 6 days prior to admission in our clinic. Emergency distal pancreatectomies were performed in both cases. CONCLUSIONS: Pancreatic injuries must be highly suspected in bicycle handlebar injuries, even if amylase/lipase levels or ultrasound findings seem unremarkable. The best initial strategies are early computed tomography and a quick referral to a level 1 trauma center. Distal pancreatectomy is the treatment of choice in cases of complete rupture of the pancreatic body.

[Distal Pancreatectomy with Autologous Fibrin Sealant - Implementation of an Established Concept of Tissue Sealing in Pancreatic Surgery]. / Die Pankreaslinksresektion mit autologem Fibrinkleber ­ Anwendung eines etablierten Versiegelungskonzepts in der Pankreaschirurgie.

Background: Postoperative pancreatic fistulas (POPF) remain a major concern after distal pancreatectomy. Irrespective of the technique to close the pancreatic remnant, pancreatic fistulas will occur in approximately 30 % of patients undergoing distal pancreatectomy. For the first time ever, autologous fibrin sealant (Vivostat®) was used to additionally seal the pancreatic remnant after a distal pancreatectomy. The aim was to analyse whether this changes the postoperative outcome. Patients/Material and Methods: In 2015, a technical case series was performed in 15 patients who underwent distal pancreatectomy. The pancreatic remnant was additionally sealed with autologous fibrin sealant (Vivostat®). Results: A postoperative pancreatic fistula (POPF) occurred in 5/15 patients (33 %). One patient had a POPF grade A (1/15, 6.7 %), whereas a POPF grade B occurred in 4/15 patients (26.7 %). 75 % (3/4) of the patients with a POPF grade B were sufficiently treated with antibiotics, whereas a CT-guided percutaneous drainage had to be placed only in one case. Conclusion: Autologous fibrin sealant is simple to apply and seems to be well tolerated. However, it does not seem to avoid the development of postoperative pancreatic fistulas after distal pancreatectomy.

Effects of diet-induced obesity on motivation and pain behavior in an operant assay.

Obesity has been associated with multiple chronic pain disorders, including migraine. We hypothesized that diet-induced obesity would be associated with a reduced threshold for thermal nociception in the trigeminal system. In this study, we sought to examine the effect of diet-induced obesity on facial pain behavior. Mice of two different strains were fed high-fat or regular diet (RD) and tested using a well-established operant facial pain assay. We found that the effects of diet on behavior in this assay were strain and reward dependent. Obesity-prone C57BL/6J mice fed a high-fat diet (HFD) display lower number of licks of a caloric, palatable reward (33% sweetened condensed milk or 30% sucrose) than control mice. This occurred at all temperatures, in both sexes, and was evident even before the onset of obesity. This diminished reward-seeking behavior was not observed in obesity-resistant SKH1-E (SK) mice. These findings suggest that diet and strain interact to modulate reward-seeking behavior. Furthermore, we observed a difference between diet groups in operant behavior with caloric, palatable rewards, but not with a non-caloric neutral reward (water). Importantly, we found no effect of diet-induced obesity on acute thermal nociception in the absence of inflammation or injury. This indicates that thermal sensation in the face is not affected by obesity-associated peripheral neuropathy as it occurs when studying pain behaviors in the rodent hindpaw. Future studies using this model may reveal whether obesity facilitates the development of chronic pain after injury or inflammation.

Obesity increases nociceptive activation of the trigeminal system.

BACKGROUND: Obesity is a risk factor associated with several pain syndromes. However, the mechanisms underlying the association between obesity and pain are not known. The aim of this study was to test the hypothesis that obesity enhances neuronal responses to nociceptive stimulation within the trigeminal nucleus caudalis (TNC). METHODS: Male and female C57BL/6J mice were fed a high-fat or regular diet from the time of weaning until 20 weeks of age. We then quantified neuronal activation by measuring Fos immunoreactivity within the TNC in response to a facial injection of a low dose of capsaicin (1 µg/10 µL). RESULTS: We found that 0.01% capsaicin did not significantly increase Fos immunoreactivity in control mice fed a regular diet. In contrast, this low dose of capsaicin caused a 3.3-fold increase in Fos in the TNC in obese mice (p < 0.001). CONCLUSIONS: These results support the hypothesis that diet-induced obesity in mice enhances nociceptive processing within the TNC. Diet-induced obesity may be a useful model for mechanistic studies. Future studies will improve our understanding of how obesity may contribute to trigeminal pain by sensitizing the trigeminal nociceptive system.

Effects of H(2)O(2) exposure on human sperm motility parameters, reactive oxygen species levels and nitric oxide levels.

Research has revealed that reactive oxygen species (ROS) negatively affect sperm function, both in vivo and in vitro. Sperm preparation techniques for assisted reproductive technologies (ART) are potential causes for additional ROS production. This study aimed to correlate the concentration of exogenous H(2)O(2) with sperm motility parameters and intracellular ROS and nitric oxide (NO) levels to reiterate the importance of minimising ROS levels in ART. Human spermatozoa from 10 donors were incubated and exposed to different exogenous H(2)O(2) concentrations (0, 2.5, 7.5 and 15 mum). Subsequently, motility was determined using computer-aided semen analysis, while ROS (2,7-dichlorofluorescin diacetate) and NO (diaminofluorescein-2/diacetate) were analysed using fluorescence-activated cell sorting. Results showed that H(2)O(2) did affect the sperm parameters. Exogenous H(2)O(2) was detrimental to motility and resulted in a significant increase in overall ROS and NO levels. A significant increase in static cells was seen as well. It is important to elucidate the mechanisms between intracellular ROS levels with sperm motility parameters. While this experiment demonstrated a need to reduce exogenous ROS levels during ART, it did not illustrate the cause and effect relationship of intracellular ROS and NO levels with sperm motility. Further research needs to be conducted to define a pathological level of ROS.

Ornithine decarboxylase and thymidine kinase activities and polyamine levels from selected organs of adult miniature swine receiving three concentrations of dietary menhaden oil.

Mature, female swine were randomly assigned to one of seven dietary groups. Swine in groups 1-3 were fed a cholesterol-rich diet for 55 days while the remaining groups remained on a basal swine diet. At the end of the cholesterol(Chol)-preloading period the swine in groups 1-7 were placed on menhaden oil (MO) and/or corn oil (CO) as follows: groups 1 and 4, 15% CO (control); groups 2 and 5, 0.75% MO+14.25% CO; groups 3 and 7, 15% MO; and group 6, 7.5% MO+7.5% CO. Animals were killed at the end of the approximately 6-month feeding period and portions of liver, pancreas and colon mucosa were analyzed for both ornithine decarboxylase (ODC) and thymidine kinase (TK) activity while polyamine levels were measured in the liver and pancreas. Statistical analyses were carried out by one-way and two-way ANOVA and by trend analysis. In the pancreas, the highest MO group (group 7) had significantly higher ODC levels when compared with the CO control (group 4) and the next to highest MO group (group 6) (one-way ANOVA)-all non-cholesterol preloaded groups. Using a two-way ANOVA (Chol-by-MO), liver ODC was significantly lower in the CO control when compared with the lowest and highest MO groups (groups 5 and 7, respectively), again in the non-cholesterol-preloaded animals. In the colon, the swine in the Chol-low MO group (group 2) had significantly lower TK activity than the Chol/CO control group (group 1) and Chol/Hi MO group (group 3) (one-way ANOVA) and also had significantly lower activity than all groups except the CO control (group 4) (two-way ANOVA). Liver acetylputrescine in the lowest and highest MO groups (groups 5 and 7, respectively) was significantly higher than in the CO group (group 4). Liver spermidine in the Chol-Hi MO group (group 3) was significantly higher than the Chol-Lo MO group (group 2), while the highest MO group (group 7) had a statistically higher level than the other non-cholesterol groups (groups 4-6) (one-way ANOVA). Liver spermine was significantly higher in the Chol-Hi MO group (group 3) when compared to the CO control (group 1) and the Chol-Lo MO group (group 2) (one-way ANOVA). Pancreatic putrescine in the CO control (group 4) was significantly higher than all other groups (two-way ANOVA) while spermine from the 2 Chol-MO groups (groups 2 and 3) was higher than the Chol-CO control (group 1) (one-way ANOVA). Using trend analysis, liver TK, putrescine and spermidine increased in the non-cholesterol preloaded groups with increasing dietary MO, similar to the increase seen in ODC. Thus, of the three organs studied, only liver responded to menhaden oil with changes in both ODC itself or some of its metabolic engendered products and thymidine kinase; at least for one of the parameters, ODC, change associated with dietary MO was dependent on whether the swine were preloaded with cholesterol.

Strand breaks in whole plasmid dna produced by the decay of (125)I in a triplex-forming oligonucleotide.

DNA strand breaks produced by the decay of (125)I positioned against a specific site in plasmid DNA via a triplex-forming oligonucleotide were studied both in the immediate vicinity of the site of the decay with a single nucleotide resolution and in the whole plasmid by measuring the percentages of supercoiled, open-circular and linear forms. The localized breaks are distributed within 10 bp in each direction from the decay site with maxima in both strands just opposite the (125)I-dC residue in the triplex-forming oligonucleotide. The distributions of breaks in the two DNA strands are almost symmetrical, in agreement with the geometry of the pyrimidine motif triplex. We found that about 25% of the double-strand breaks were located outside the 90-bp fragment containing the triplex-forming oligonucleotide binding sequence. The ratio of single- to double-strand breaks in the whole plasmid was 11 for bound triplex-forming oligonucleotide compared to 26 when the triplex-forming oligonucleotide was free in solution. The number of double-strand breaks per decay of (125)I was 0.46 for bound triplex-forming oligonucleotide and 0.17 for free triplex-forming oligonucleotide. Comparing the data on the localized damage and those for the whole plasmid, we concluded that, in addition to DNA breaks that are confined to a helical turn around the (125)I atom, the decay can produce breaks hundreds of base pairs away in the plasmid molecule. This linear plasmid molecule containing radiation-induced damage at a specific DNA site should be useful in studies of the molecular mechanisms of DNA repair.

Development of DNA-based radiopharmaceuticals carrying Auger-electron emitters for antigene radiotherapy.

PURPOSE: Antigene radiotherapy (AR) is based on targeting localized radiodamage to specific sites in the genome by using sequence-specific triplex-forming oligonucleotides (TFO) to carry Auger-electron-emitters (A-Ettr) such as Iodine-125 (125I) to the target gene sequence. The radiodecay of an A-Ettr produces a cascade of low-energy electrons and creates a highly positively-charged daughter atom; delivered by a TFO, it should produce double-strand breaks (dsb) localized to the specific DNA target sequence. The result should be a "knock-out" of the targeted gene. METHODS AND MATERIALS: As a model, we used the MDR1 gene amplified nearly 100 times in the human KB-V1 carcinoma cell line. Chemically modified TFO complementary to the polypurine/polypyrimidine region of the MDR1 gene were synthesized and radiolabeled with 125I-dCTP by the primer extension method. Purified plasmid and genomic DNA and extracted nuclei were treated with 125I-TFO and analyzed for sequence-specific cleavage by electrophoresis in agarose gel and Southern hybridization. RESULTS: We created 125I-TFO that could effectively recognize, bind, and cleave the target sequence in plasmid and genomic DNA. We showed that these 125I-TFO in nanomolar concentrations were able to cleave the target MDR1 gene sequence in a natural environment, i.e., within the eucaryotic nucleus. CONCLUSION: 125I-TFO can effectively introduce sequence-specific dsb to a target within the MDR1 gene, both in purified DNA and inside intact nuclei. Chemically modified TFO conjugated with nuclear localization signal appear to be a promising delivery vehicle for future in vivo trials of AR.

Use of polyethylenimine-adenovirus complexes to examine triplex formation in intact cells.

Triplex-forming oligonucleotides (TFOs) show potential for sequence-specific DNA binding and inhibition of gene expression. We have applied this antigene strategy using a TFO incorporating an Auger-emitting radionucleotide, 125I, to study the production of double-strand breaks (dsb) in the rat aquaporin 5 (rAQP5) cDNA. 125I-TFO bound to the pCMVrAQP5 plasmid in vitro in a dose-dependent manner and formed stable triplexes up to 65 degrees C and in the presence of 140 mM KCl. Further, 125I-TFO resulted in a predictable dsb when analyzed by Southern hybridization. To deliver TFOs to epithelial cells, we employed 125I-TFO-polyethyleneimine-adenovirus (125I-TFO-PEI-Ad) complexes. We hypothesized that these complexes would take advantage of adenoviral characteristics to transfer 125I-TFO to the cell nucleus. Adenovirus-containing complexes brought about greater uptake and nuclear localization of TFOs compared with delivery with 125I-TFO-PEI complexes alone. No significant degradation of 125I-TFO was found after delivery into cells using PEI-Ad complexes and freezing and thawing. We next used PEI-Ad complexes to deliver 125I-TFO and pCMVrAQP5 separately to epithelial cells to determine if triplexes can form de novo within cells, resulting in the specific dsb in the rAQP5 cDNA. After delivery, cell pellets were stored at -80 degrees C for more than 60 days. Thereafter, plasmid DNA was isolated from cells and analyzed for dsb by Southern hybridization. However, none were detected. We conclude that under the experimental conditions employed, effective triplexes, with 125I-TFO and pCMVrAQP5, do not form de novo inside cells.

Targeting the human mdr1 gene by 125I-labeled triplex-forming oligonucleotides.

Antigene radiotherapy is our approach to targeting specific sites in the genome by combining the highly localized DNA damage produced by the decay of Auger electron emitters, such as 125I, with the sequence-specific action of triplex-forming oligonucleotides (TFO). As a model, we used the multidrug resistance gene (mdr1) overexpressed and amplified nearly 100 times in the human KB-V1 carcinoma cell line. Phosphodiester pyrrazolopyrimidine dG (PPG)-modified TFO complementary to the polypurine-polypyrimidine region of the mdr1 gene were synthesized and labeled with 125I-dCTP at the C5 position of two cytosines by the primer extension method. 125I-TFO were delivered into KB-V1 cells with several delivery systems. DNA from the 125I-TFO-treated cells was recovered and analyzed for sequence-specific cleavage in the mdr1 target by Southern hybridization. Experiments with plasmid DNA containing the mdr1 polypurine-polypyrimidine region and with purified genomic DNA confirmed the ability of the designed 125I-TFO to bind to and introduce double-strand breaks into the target sequence. We showed that 125I-TFO in nanomolar concentrations can recognize and cleave a target sequence in the mdr1 gene in situ, that is, within isolated nuclei and intact digitonin-permeabilized cells. Our results demonstrate the ability of 125I-TFO to target specific sequences in their natural environment, that is, within the eukaryotic nucleus. The nearly 100-fold amplification of the mdr1 gene in KB-V1 cells affords a very useful cell culture model for evaluation of methods to produce sequence-specific DNA double-strand breaks for gene-specific radiotherapy.

The stability of DNA triplexes inside cells as studied by iodine-125 radioprinting.

We studied the stability of a DNA triplex resulting from the binding of a 38 nt long purine motif triplex-forming oligonucleotide (TFO) to a covalently closed plasmid containing a target sequence from the human HPRT gene. Our in vitro experiments showed that the triplex formed at plasmid and TFO concentrations as low as 10(-9)M. Once formed, the triplex was remarkably stable and could withstand 10 min incubation at 65 degrees C. We next delivered these TFO-plasmid complexes into cultured human cells. To monitor the TFO-plasmid complexes inside cells we applied a new technique that we call 'radioprinting'. Because the TFO was(125)I labeled, we could quantitatively monitor the triplexes by measuring(125)I-induced DNA strand breaks in the target plasmid sequence. We found that the triplexes remain stable inside the cells for at least 48 h. Based on these findings we propose using TFO for indirect labeling of intact plasmid DNA. As a demonstration, we show that the intracellular distribution of a fluorescein-labeled TFO was different when it was liposome-delivered into cultured human cells alone or in a complex with the plasmid. In the latter case, the fluorescence was detected in nearly all the cells while detection of the plasmid by use of a marker gene (beta-galactosidase) revealed expression of the gene in only half of the cells.

Identification of an activating transcription factor (ATF) binding site in the human transforming growth factor-beta 2 promoter.

Transforming growth factor TGF-beta 2 is encoded by multiple mRNA transcripts of 5.8, 5.1, 4.0, 3.8, and 2.8 kilobase pairs (kb) that are expressed in various human and monkey cells. Northern blot analysis using genomic fragments of DNA was used to demonstrate that some of this size heterogeneity is due to differences in the length of the 5'-untranslated region. Probes that were colinear with the first 600 nucleotides of the 5'-untranslated region detected only the 5.8-, 4.0-, and 3.8-kb transcripts. In order to identify DNA elements that regulate the transcription of these mRNA transcripts, deletion constructs of 5'-flanking DNA were ligated to the coding region for chloramphenicol acetyltransferase (CAT) and analyzed for promoter activity in several cell lines. Sequences responsible for putative enhancer and silencer regions were identified between -778 and -40 relative to the transcription initiation site. Addition of a cyclic AMP-responsive element/activating transcription factor-like element at -74 resulted in a 5-10-fold increase in CAT activity over that expressed with a construct that contained only the TATA box. This increase in CAT activity was suppressed by the addition of DNA sequences between -257 and -187, whereas sequences between -778 and -257 stimulated CAT activity. Point mutations within the ATF binding site at -74 resulted in a marked decrease in CAT expression. Cotransfection with ATF-1 or ATF-2 expression plasmids resulted in both dose-dependent stimulatory and inhibitory activities that were cell type-dependent. These studies identify multiple transcription initiation sites for TGF-beta 2 and demonstrate that transcription from one of these promoters is dependent upon an ATF binding site located 5' of the TATA box.