Use of a novel vessel-sealing device for peripheral lung biopsy and lung lobectomy in a cadaveric model.

OBJECTIVE: To evaluate the Caiman vessel-sealing device for peripheral lung biopsy and total lung lobectomy in cadaveric canine lung lobes. MATERIAL AND METHODS: Twelve lung lobes were randomly assigned to peripheral lung biopsy (n=6) or total lung lobectomy (n=6) with the 12-mm Caiman vessel-sealing device. Lungs were connected to a ventilator set at 10 breaths per minute with an initial pressure of 5 cm H2 O during the procedure. The lungs were submerged in water for leak testing and the pressure increased until leakage occurred. RESULTS: Mean airway pressure at which leakage occurred was 39.17 ±13.20 cm H2 O for peripheral lung biopsies and 38.33 ±13.67 cm H2 O for total lung lobectomies. None of the samples leaked below 25 cm H2 O, which is well above the physiologic airway pressure. Histologically, the largest bronchial diameter at the sealed area was 8.84 mm and the extent of collateral damage was approximately 2.7 mm in all specimens. CLINICAL SIGNIFICANCE: The Caiman vessel-sealing device was successfully used for peripheral lung biopsy and total lung lobectomy in cadaveric canine lung lobes. All sealed lung lobes tolerated supra-physiologic airway pressure, displayed minimal collateral damage, and were of good diagnostic quality. Further experimental studies are needed to evaluate the clinical safety of the device for peripheral lung biopsy or total lung lobectomy.

The EIGER detector for low-energy electron microscopy and photoemission electron microscopy.

EIGER is a single-photon-counting hybrid pixel detector developed at the Paul Scherrer Institut, Switzerland. It is designed for applications at synchrotron light sources with photon energies above 5 keV. Features of EIGER include a small pixel size (75 µm × 75 µm), a high frame rate (up to 23 kHz), a small dead-time between frames (down to 3 µs) and a dynamic range up to 32-bit. In this article, the use of EIGER as a detector for electrons in low-energy electron microscopy (LEEM) and photoemission electron microscopy (PEEM) is reported. It is demonstrated that, with only a minimal modification to the sensitive part of the detector, EIGER is able to detect electrons emitted or reflected by the sample and accelerated to 8-20 keV. The imaging capabilities are shown to be superior to the standard microchannel plate detector for these types of applications. This is due to the much higher signal-to-noise ratio, better homogeneity and improved dynamic range. In addition, the operation of the EIGER detector is not affected by radiation damage from electrons in the present energy range and guarantees more stable performance over time. To benchmark the detector capabilities, LEEM experiments are performed on selected surfaces and the magnetic and electronic properties of individual iron nanoparticles with sizes ranging from 8 to 22 nm are detected using the PEEM endstation at the Surface/Interface Microscopy (SIM) beamline of the Swiss Light Source.

Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science.

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e(-) electronic noise charge (<100 eV) with no active cooling. The 48 × 48 pixels JUNGFRAU 0.4 prototype can be combined with a charge-sharing suppression mask directly placed on the sensor, which keeps photons from hitting the charge-sharing regions of the pixels. The mask consists of a 150 µm tungsten sheet, in which 28 µm-diameter holes are laser-drilled. The mask is aligned with the pixels. The noise and gain characterization, and single-photon detection as low as 1.2 keV are shown. The performance of JUNGFRAU 0.4 without the mask and also in the charge-sharing suppression configuration (with the mask, with a `software mask' or a `cluster finding' algorithm) is tested, compared and evaluated, in particular with respect to the removal of the charge-sharing contribution in the spectra, the detection efficiency and the photon rate capability. Energy-dispersive and imaging experiments with fluorescence X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy-dispersive detection system.

Laparoscopy for the treatment of ovarian remnant syndrome in four dogs and two cats.

OBJECTIVE: To describe the clinical workup and laparoscopic treatment of ovarian remnant syndrome in dogs and cats. MATERIAL AND METHODS: After confirming the diagnosis with some or all of the following tests - vaginoscopy with cytology, hormonal tests, and ultrasound - laparoscopic removal of the ovarian remnants was performed. A three-portal technique was used in the four dogs and a two-portal technique in the two cats. RESULTS: All patients recovered well and were discharged the same day. No post-operative complications occurred in any patient. CONCLUSION AND CLINICAL RELEVANCE: Overall, in the hands of an experienced laparoscopic surgeon, laparoscopic removal of ovarian remnants appears to be a safe procedure in dogs and cats. In addition, laparoscopy offers the advantages of excellent visualization and a reduced morbidity for the patient. Careful case selection and complete pre-operative workup to rule out co-morbidities or underlying neoplasia are important. As with any laparoscopy the surgeon should always be prepared to convert to an open laparotomy if necessary.

Laparoscopic-assisted cryptorchidectomy in a cat.

A 21-month-old male castrated domestic short hair cat was presented due to suspected unilateral abdominal cryptorchidism. Unilateral abdominal cryptorchidism was confirmed with ultrasonography and laparoscopic-assisted cryptorchidectomy was performed. Laparoscopic-assisted cryptorchidectomy is a simple, fast and safe method for the treatment of abdominal cryptorchidism in dogs and cats, offering the benefits of minimal invasive surgery, which is still underreported in the veterinary literature.

A cellular screen identifies ponatinib and pazopanib as inhibitors of necroptosis.

Necroptosis is a form of regulated necrotic cell death mediated by receptor-interacting serine/threonine-protein kinase 1 (RIPK1) and RIPK3. Necroptotic cell death contributes to the pathophysiology of several disorders involving tissue damage, including myocardial infarction, stroke and ischemia-reperfusion injury. However, no inhibitors of necroptosis are currently in clinical use. Here we performed a phenotypic screen for small-molecule inhibitors of tumor necrosis factor-alpha (TNF-α)-induced necroptosis in Fas-associated protein with death domain (FADD)-deficient Jurkat cells using a representative panel of Food and Drug Administration (FDA)-approved drugs. We identified two anti-cancer agents, ponatinib and pazopanib, as submicromolar inhibitors of necroptosis. Both compounds inhibited necroptotic cell death induced by various cell death receptor ligands in human cells, while not protecting from apoptosis. Ponatinib and pazopanib abrogated phosphorylation of mixed lineage kinase domain-like protein (MLKL) upon TNF-α-induced necroptosis, indicating that both agents target a component upstream of MLKL. An unbiased chemical proteomic approach determined the cellular target spectrum of ponatinib, revealing key members of the necroptosis signaling pathway. We validated RIPK1, RIPK3 and transforming growth factor-ß-activated kinase 1 (TAK1) as novel, direct targets of ponatinib by using competitive binding, cellular thermal shift and recombinant kinase assays. Ponatinib inhibited both RIPK1 and RIPK3, while pazopanib preferentially targeted RIPK1. The identification of the FDA-approved drugs ponatinib and pazopanib as cellular inhibitors of necroptosis highlights them as potentially interesting for the treatment of pathologies caused or aggravated by necroptotic cell death.

Radiation hardness assessment of the charge-integrating hybrid pixel detector JUNGFRAU 1.0 for photon science.

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications in free electron lasers, particularly SwissFEL, and synchrotron light sources. JUNGFRAU is an automatic gain switching, charge-integrating detector which covers a dynamic range of more than 10(4) photons of an energy of 12 keV with a good linearity, uniformity of response, and spatial resolving power. The JUNGFRAU 1.0 application-specific integrated circuit (ASIC) features a 256 × 256 pixel matrix of 75 × 75 µm(2) pixels and is bump-bonded to a 320 µm thick Si sensor. Modules of 2 × 4 chips cover an area of about 4 × 8 cm(2). Readout rates in excess of 2 kHz enable linear count rate capabilities of 20 MHz (at 12 keV) and 50 MHz (at 5 keV). The tolerance of JUNGFRAU to radiation is a key issue to guarantee several years of operation at free electron lasers and synchrotrons. The radiation hardness of JUNGFRAU 1.0 is tested with synchrotron radiation up to 10 MGy of delivered dose. The effect of radiation-induced changes on the noise, baseline, gain, and gain switching is evaluated post-irradiation for both the ASIC and the hybridized assembly. The bare JUNGFRAU 1.0 chip can withstand doses as high as 10 MGy with minor changes to its noise and a reduction in the preamplifier gain. The hybridized assembly, in particular the sensor, is affected by the photon irradiation which mainly shows as an increase in the leakage current. Self-healing of the system is investigated during a period of 11 weeks after the delivery of the radiation dose. Annealing radiation-induced changes by bake-out at 100 °C is investigated. It is concluded that the JUNGFRAU 1.0 pixel is sufficiently radiation-hard for its envisioned applications at SwissFEL and synchrotron beam lines.

[Management of dysphagia in internal intensive-care medicine]. / Dysphagiemanagement in der internistischen Intensivmedizin.

Physicians specializing in dysphagia are needed in modern intensive care medicine. Long-term intubation is associated with aspiration and swallowing disorders. Early and standardised dysphagia management should be initiated during a patient's stay on intensive care unit. A clinically experienced, interdisciplinary team is required to provide optimal care for critically ill patients with dysphagia. Intensive care physicians should therefore know about basics in dysphagiology.

In vitro biomechanical comparison of a newly designed interlocking nail system to a standard DCP. Testing of cat femora in an osteotomy gap model.

OBJECTIVE: To describe a newly designed interlocking nail system (Targon® Vet System, TVS) tested in a model of diaphyseal femoral fractures in cats. MATERIAL AND METHODS: Introduction of the TVS and presentation of the system components. Evaluation of application range and biomechanical testing of the TVS in cadaver bones under cyclic loading until fatigue failure occurred. The first two test groups compared the influence of implantation and immediate removal of the TVS locking bolts and six holes created by 2.0 mm cortical screws on the stability of feline femora. In the third group the two fixation systems were compared to each other with implants in place in an osteotomy gap model. The failure mode was statistically compared for each group (p < 0.05). RESULTS: Femora after implantation and removal of the bolts of the TVS were significantly stiffer than after implantation and removal of the six 2.0 mm cortical screws. In the osteotomy gap model, femora with the TVS in place failed some- what later, but not statistically significant, than the opposite femur of the same cat with the 2.0 8-hole DCP in place. CONCLUSION AND CLINICAL RELEVANCE: Using this testing method, stability of the TVS seems to be biomechanically comparable to conventional osteosynthesis plate systems. Therefore the TVS may be an encouraging alternative to conventional osteosynthesis systems in diaphyseal fractures, offering several advantages without the need for extensive specialized equipment.

Successful treatment of permethrin toxicosis in two cats with an intravenous lipid administration.

The present work describes successful treatment of permethrin toxicosis in two cats with a novel therapy of intravenous lipid administration. Two cats presented in lateral recumbency and with generalized tremor after they had been incidentally treated with permethrin for flea control by their owners. Initial therapy consisted of diazepam, propofol, bathing, and intravenous fluids. After an initial bolus of 2mg/kg BW pentobarbital a pentobarbital continuous rate infusion (CRI) was started. Both cats received an emulsion of 20% soybean oil and 80% olive oil, commonly used as fat component of total parenteral nutrition in humans, later in the course of therapy. A bolus of 2 ml/kg BW of the emulsion followed by a CRI of 4 ml/kg BW/h for 4 hours was administered via a jugular catheter as reported previously. One cat received two cycles of therapy with intravenous lipid whereas the other cat needed just one application. Both cats recovered completely without requiring any further treatment. In conclusion, administration of intravenous lipids for permethrin toxicosis in cats is a novel treatment approach which seems to be highly effective in shortening the recovery time for permethrin toxicosis and possibly other fat-soluble toxins.

Chromosome spatial clustering inferred from radiogenic aberrations.

PURPOSE: Analysing chromosome aberrations induced by low linear energy transfer (LET) radiation in order to characterize systematic spatial clustering among the 22 human autosomes in human lymphocytes and to compare their relative participation in interchanges. MATERIALS AND METHODS: A multicolour fluorescence in situ hybridization (mFISH) data set, specifying colour junctions in metaphases of human peripheral blood lymphocytes 72 h after in vitro exposure to low LET radiation, was analysed separately and in combination with previously published results. Monte Carlo computer simulations and mathematical modelling guided data analysis. RESULTS AND CONCLUSIONS: Statistical tests on aberration data confirmed two clusters of chromosomes, [1, 16, 17, 19, 22] and [13, 14, 15, 21, 22], as having their members being on average closer to each other than randomness would predict. The first set has been reported previously to be near the centre of the interphase nucleus and to be formed mainly by gene-rich chromosomes, while the second set comprises the nucleolus chromosomes. The results suggest a possible interplay between chromosome positioning and transcription. A number of other clusters suggested in the literature were not confirmed and considerable randomness of chromosome-chromosome juxtapositions was present. In addition, and consistent with previous results, it was found that chromosome participation in interchanges is approximately proportional to the two-thirds power of the DNA content.

Analyzing the neocortical fine-structure.

Cytoarchitectonic fields of the human neocortex are defined by characteristic variations in the composition of a general six-layer structure. It is commonly accepted that these fields correspond to functionally homogeneous entities. Diligent techniques were developed to characterize cytoarchitectonic fields by staining sections of post-mortem brains and subsequent statistical evaluation. Fields were found to show a considerable interindividual variability in extent and relation to macroscopic anatomical landmarks. With upcoming new high-resolution magnetic resonance imaging (MRI) protocols, it appears worthwhile to examine the feasibility of characterizing the neocortical fine-structure from anatomical MRI scans, thus, defining neocortical fields by in vivo techniques. A fixated brain hemisphere was scanned at a resolution of approximately 0.3 mm. After correcting for intensity inhomogeneities in the dataset, the cortex boundaries (the white/grey matter and grey matter/background interfaces) were determined as a triangular mesh. Radial intensity profiles following the shortest path through the cortex were computed and characterized by a sparse set of features. A statistical similarity measure between features of different regions was defined, and served to define the extent of Brodmann's Areas 4, 17, 44 and 45 in this dataset.

Preparation of curved root canals with rotary FlexMaster instruments compared to Lightspeed instruments and NiTi hand files.

AIM: To compare the recently introduced rotary FlexMaster instruments with Lightspeed instruments and NiTi hand files in preparing curved root canals. METHODOLOGY: Root canals of extracted molars were shaped with rotary FlexMaster instruments ('FM': n = 45), Lightspeed instruments ('LS': n = 46), and NiTi hand files (n = 45) using the balanced-force technique. The apical preparation size was 40. Root canal instrumentation was carried out in a phantom head under clinical conditions. A re-assembly technique allowed a comparison of the canal outline before and after preparation. Root sections 2.5 mm short of working length were used to calculate the percentage of prepared canal outline (= PPO) and the amount of root canal transportation. Loss of working length, fracture rate and time spent on complete preparation were also recorded. RESULTS: The highest PPO values were found in the LS group (mean = 63% [95% CI: 55%; 70%]). Although not statistically significant, lower PPO values were detected for FM instruments (mean = 55% [95% CI: 49%; 62%]) and for hand files (mean = 53% [95% CI: 47%; 59%]). The incidence of root canal transportation exceeding 0.1 mm was significantly lower in the LS group than in the FM group. Loss of working length of 0.5 mm occurred in five cases (LS group: 4x; FM group: 1x). Two LS instruments fractured. Half the time was needed for root canal preparation with FM instruments than with hand files. CONCLUSIONS: Rotary FM instruments are suitable for preparing curved root canals. They provided results similar to LS instruments with minimal risk of instrument fracture but increased risk of root canal transportation.

Computer analysis of mFISH chromosome aberration data uncovers an excess of very complicated metaphases.

PURPOSE: To analyse spectra of chromosome aberrations induced in vitro by low LET radiation, in order to characterize radiation damage mechanisms quantitatively. METHODS: Multiplex fluorescence in situ hybridization (mFISH) allows the simultaneous identification of each homologous chromosome pair by its own colour. mFISH data, specifying number distributions for colour junctions in metaphases of human peripheral blood lymphocytes 72 hours after exposure in vitro to a 3 Gy gamma-ray dose, were combined with similar, previously published results. Monte Carlo computer implementations of radiobiological models for chromosome aberration production guided quantitative analyses, which took into account distribution of cells among different metaphases and lethal effects or preferential elimination of some aberrations at cell division. RESULTS AND CONCLUSIONS: Standard models of DNA damage induction/repair/misrepair explain the main trends of the data as regards the fraction of metaphases having a particular number of colours involved in colour junctions. However, all standard models systematically under-predict the observed fraction of metaphases where a large number of different chromosomes participate in aberrations. An early appearance of chromosomal instability could explain most of the discrepancies.

Impairment of mitogenic activation of peripheral blood lymphocytes in Alzheimer's disease.

Cell-cycle dysregulation might be critically involved in the process of neurodegeneration in Alzheimer's disease (AD). We now provide evidence for a dysfunction of the cell division cycle as a more general cellular phenomenon of the disease. Peripheral blood lymphocytes, stimulated with mitogenic compounds, were less able to express CD69, an early proliferation marker, in AD patients than in age-matched controls. Expression levels of CD69 of both T-cells and B-cells correlated inversely with the Mini-mental Scale. The results suggest that a systemic failure of cellular proliferation control might be of critical importance for the pathomechanism of AD.

Quasispecies heterogeneity of the carboxy-terminal part of the E2 gene including the PePHD and sensitivity of hepatitis C virus 1b isolates to antiviral therapy.

Two regions within the HCV genome, hypervariable region 1 (HVR1) within the envelope (E)2 region and the PKR-binding domain (PKRbD) comprising the interferon sensitivity determining region (ISDR) within the nonstructural (NS)5A protein, have been reported to correlate with the outcome of antiviral treatment. Recently, a PKR/eIF2alpha phosphorylation homology domain (PePHD) within the E2 protein of HCV-1 isolates was described to inhibit PKR in vitro. PePHD deleted HCV-1 mutants remain capable of binding PKR to some extent while inhibition of PKR was found to be abolished by carboxy-terminal truncated E2 protein. The importance of mutations and quasispecies heterogeneity within the carboxy-terminal part of the E2 protein comprising the PePHD of HCV-1b is unknown. Therefore, the carboxy-terminal part of the HCV E2 gene (codons 618-746) including the PePHD was analyzed by sequencing of PCR products and individual clones of 41 HCV-1b-infected patients with sustained (SR, n = 12), end-of-treatment (ETR, n = 10), or no virological (NR, n = 19) response to antiviral therapy. Two highly conserved regions (codons 658-673 comprising the PePHD and codons 675-704) and one variable region (codons 705-720) were detected within the carboxy-terminal part of E2. No significant correlation of specific mutations or number of mutations with treatment response was observed for the PePHD and the carboxy-terminal part of the E2 protein. Phylogenetic and conformational analyses showed no specific clusters related to treatment outcome. Calculation of genetic complexity and diversity based on nucleotide sequence analyses of 20 individual clones per patient showed no differences between matched SR, ETR, and NR patients. However, calculation of genetic complexity and diversity on the basis of amino acid sequences showed significantly lower normalized Shannon entropy as well as mean Hamming distances for SR patients than in ETR and NR patients (P = 0.029 and P = 0.027, respectively). This indicates that patients achieving a sustained virological response to interferon-alpha-based antiviral therapy may elicit more effective immunological pressure, resulting in continuous clearing of individual variants of HCV quasispecies.

Developmentally induced microencephalopathy in guinea pigs--embryonic glial cell activation marks selective neuronal death.

We have recently shown that in utero treatment of guinea pigs with the DNA methylating substance methylazoxymethanol acetate (MAM) on gestation day (GD) 24 results in neocortical microencephalopathy, increased protein kinase C activity and altered processing of the amyloid precursor protein in neocortex of the offsprings. In order to identify the primary neuronal lesions produced by MAM-treatment, we mapped the 5-bromo-2'-deoxyuridine (BrdU)-incorporation in dividing neurons on GD 24 and we followed the effects of MAM-treatment on GD 24 on embryonic immediate early gene expression and on glial cell activation. BrdU injected on GD 24 labeled many neurons of the ventricular zone and of the intermediate zone but only scattered neurons of the cortical plate. When time-mated guinea pigs were injected intraperitoneally with MAM on GD 24, we observed the activation of microglial cells in the ventricular/intermediate zone and the appearence of astrocytes between the intermediate zone and the cortical plate, 48 h after intoxification. The activation of glial cells was accompanied by the neuronal expression of c-Fos but not of c-Jun in the ventricular/intermediate zone. Based on our observations on BrdU-incorporation and on the morphological outcome of MAM treatment in the juvenile guinea pig, our data presented here indicate that selective neurodegeneration during development induces the activation of both phagocytotic microglial cells and of astrocytes which might trophically support damaged neurons surviving this lesion procedure.

PECAM-1/CD31 trans-homophilic binding at the intercellular junctions is independent of its cytoplasmic domain; evidence for heterophilic interaction with integrin alphavbeta3 in Cis.

PECAM-1/CD31 is a cell adhesion and signaling molecule that is enriched at the endothelial cell junctions. Alternative splicing generates multiple PECAM-1 splice variants, which differ in their cytoplasmic domains. It has been suggested that the extracellular ligand-binding property, homophilic versus heterophilic, of these isoforms is controlled by their cytoplasmic tails. To determine whether the cytoplasmic domains also regulate the cell surface distribution of PECAM-1 splice variants, we examined the distribution of CD31-EGFPs (PECAM-1 isoforms tagged with the enhanced green fluorescent protein) in living Chinese hamster ovary cells and in PECAM-1-deficient endothelial cells. Our results indicate that the extracellular, rather than the cytoplasmic domain, directs PECAM-1 to the cell-cell borders. Furthermore, coculturing PECAM-1 expressing and deficient cells along with transfection of CD31-EGFP cDNAs into PECAM-1 deficient cells reveal that this PECAM-1 localization is mediated by homophilic interactions. Although the integrin alphavbeta3 has been shown to interact with PECAM-1, this trans-heterophilic interaction was not detected at the borders of endothelial cells. However, based on cocapping experiments performed on proT cells, we provide evidence that the integrin alphavbeta3 associates with PECAM-1 on the same cell surface as in a cis manner.