A laser-based system to heat nuclear fuel pellets at high temperature.

Annealing tests are of utmost importance in nuclear fuel research, particularly to study the thermophysical properties of the material, microstructure evolution, or the released gas as a function of temperature. As an alternative to conventional furnace or induction annealing, we report on a laser-heating experiment allowing one to heat a nuclear fuel pellet made of uranium dioxide, UO2, or potentially other nuclear fuel pellets in an isothermal and controlled manner. For that purpose, we propose to use an indirect heating method based on a two compartment tungsten crucible, one containing the sample and the other acting as a laser susceptor for efficient and homogeneous heating of the assembly. With this concept, we demonstrate the heating of UO2 samples up to 1500 °C at a maximum heating rate of 30 °C/s with the use of two 500 W lasers. The system is, however, scalable to higher heating rates or higher temperatures by increasing the laser power up to few kW. The experiment has been designed to heat a pressurized water reactor fuel pellet, but the concept could be easily applied to other sample geometries or materials.

A robust and efficient automatic method to segment maize FASGA stained stem cross section images to accurately quantify histological profile.

BACKGROUND: Grasses internodes are made of distinct tissues such as vascular bundles, epidermis, rind and pith. The histology of grasses stem was largely revisited recently taking advantage of the development of microscopy combined with the development of computer-automated image analysis workflows. However, the diversity and complexity of the histological profile complicates quantification. Accurate and automated analysis of histological images thus remains challenging. RESULTS: Herein, we present a workflow that automatically segments maize internode cross section images into 40 distinct tissues: two tissues in the epidermis, 19 tissues in the rind, 14 tissues in the pith and 5 tissues in the bundles. This level of segmentation is achieved by combining the Hue, Saturation and Value properties of each pixel and the location of each pixel in FASGA stained cross sectiona. This workflow is likewise able to highlight significant and subtle histological genotypic variations between maize internodes. The grain of precision provided by the workflow also makes it possible to demonstrate different levels of sensitivity to digestion by enzymatic cocktails of the tissues in the pith. The precision and strength of the workflow is all the more impressive because it is preserved on cross section images of other grasses such as miscanthus or sorghum. CONCLUSIONS: The fidelity of this tool and its capacity to automatically identify variations of a large number of histological profiles among different genotypes pave the way for its use to identify genotypes of interest and to study the underlying genetic bases of variations in histological profiles in maize or other species.

High throughput accurate method for estimating in vitro dry matter digestibility of maize silage.

BACKGROUND: Since the introduction of studies on maize silage digestibility at the end of the nineteenth century, protocols to estimate dry matter digestibility have not stopped evolving. Since the early 1980s, the protocol developed by Aufrère became a benchmark in many laboratories to estimate in vitro dry matter digestibility. In order to increase its throughput, to facilitate its execution and to decipher the impact of the different parameters of the protocol we decided to test the combination of 7 parameters in 21 different protocols. RESULTS: We thus tested the impact of (1) the presence or absence of pepsin in HCl solution, (2) the temperature of incubation during enzymatic hydrolysis, (3) the presence or absence of a gelatinization step, (4) washing/rinsing versus neutralization step, (5) the presence or absence of α-amyloglucosidase in enzymatic solution, (6) the duration of cellulase incubation, and (7) the concentration of the cellulase solution. The major result of our work highlighted that it was essential to carry out a gelatinization step to correctly estimate the in vitro dry matter digestibility of maize silage. CONCLUSIONS: The proposed protocol in this paper is innovative, reliable, highthroughput and easy to implement in many laboratories to accurately quantity in vitro dry matter digestibility.

Technology development of hyperthermic pressurized intraperitoneal aerosol chemotherapy (hPIPAC).

BACKGROUND: Optimized drug delivery systems are needed for intraperitoneal chemotherapy. The aim of this study was to develop a technology for applying pressurized intraperitoneal aerosol chemotherapy (PIPAC) under hyperthermic conditions (hPIPAC). METHODS: This is an ex-vivo study in an inverted bovine urinary bladder (IBUB). Hyperthermia was established using a modified industry-standard device (Humigard). Two entry and one exit ports were placed. Warm-humid CO2 was insufflated in the IBUB placed in a normothermic bath to simulate body thermal inertia. The temperature of the aerosol, tissue, and water bath was measured in real-time. RESULTS: Therapeutic hyperthermia (target tissue temperature 41-43 °C) could be established and maintained over 30 min. In the first phase (insufflation phase), tissue hyperthermia was created by insufflating continuously warm-humid CO2. In the second phase (aerosolization phase), chemotherapeutic drugs were heated up and aerosolized into the IBUB. In a third phase (application phase), hyperthermia was maintained within the therapeutic range using an endoscopic infrared heating device. In a fourth phase, the toxic aerosol was discarded using a closed aerosol waste system (CAWS). DISCUSSION: We introduce a simple and effective technology for hPIPAC. hPIPAC is feasible in an ex-vivo model by using a combination of industry-standard medical devices after modification. Potential pharmacological and biological advantages of hPIPAC over PIPAC should now be evaluated.

Early Transmural Response Assessed Using Magnetic Resonance Imaging Could Predict Sustained Clinical Remission and Prevent Bowel Damage in Patients with Crohn's Disease Treated with Anti-Tumour Necrosis Factor Therapy.

BACKGROUND: Magnetic resonance imaging [MRI] is a promising tool to evaluate therapeutic efficacy in ileocolonic Crohn's disease [CD]. AIMS: We aimed to assess the feasibility of early MRI evaluation (week 12 [W12]) to predict corticosteroid-free remission [CFREM] at W52 and prevent long-term bowel damage. METHODS: All patients with active CD needing anti-tumour necrosis factor [anti-TNF] therapy were consecutively enrolled in this multicentre prospective study. MRI was performed before starting therapy, at W12 and W52. CFREM was defined as Crohn's Disease Activity Index < 150, C-reactive protein < 5 mg/L and faecal calprotectin < 250 µg/g, with no switch of anti-TNF agents, no bowel resection and no therapeutic intensification between W12 and W52. RESULTS: Among 46 patients, 22 [47.8%] achieved CFREM at W52. Anti-TNF agents were able to heal almost all CD lesions as soon as W12 [p < 0.05]. Early transmural response defined as a 25% decrease of either Clermont score (odds ratio [OR] = 7.7 [1.7-34.0], p < 0.001) or Magnetic Resonance Index of Activity (OR = 4.2 [1.3-13.3], p = 0.015) was predictive of CFREM at W52. Achieving at least two items on W12-MRI among ulceration healing, disappearance of enlarged lymph nodes or sclerolipomatosis, ΔADC [apparent diffusion coefficient] > +10% or ΔRCE [relative contrast enhancement] > -30% was associated with a likelihood of CFREM at W52 of 84.6% vs 37.5% in patients without transmural response [p < 0.001]. Early transmural response could prevent bowel damage progression over time using Clermont score (hazard ratio = 0.21 [0.0-0.9]; p = 0.037). CONCLUSION: Evaluation of early transmural response by MRI is feasible and is a promising end point to monitor therapeutic efficacy in patients with CD.

COVID-19: impact on colorectal surgery.

AIM: The rapid spread of the COVID-19 pandemic has created unprecedented challenges for the medical and surgical healthcare systems. With the ongoing need for urgent and emergency colorectal surgery, including surgery for colorectal cancer, several questions pertaining to operating room (OR) utilization and techniques needed to be rapidly addressed. METHOD: This manuscript discusses knowledge related to the critical considerations of patient and caregiver safety relating to personal protective equipment (PPE) and the operating room environment. RESULTS: During the COVID-19 pandemic, additional personal protective equipment (PPE) may be required contingent upon local availability of COVID-19 testing and the incidence of known COVID-19 infection in the respective community. In addition to standard COVID-19 PPE precautions, a negative-pressure environment, including an OR, has been recommended, especially for the performance of aerosol-generating procedures (AGPs). Hospital spaces ranging from patient wards to ORs to endoscopy rooms have been successfully converted from standard positive-pressure to negative-pressure spaces. Another important consideration is the method of surgical access; specifically, minimally invasive surgery with pneumoperitoneum is an AGP and thus must be carefully considered. Current debate centres around whether it should be avoided in patients known to be infected with SARS-CoV-2 or whether it can be performed under precautions with safety measures in place to minimize exposure to aerosolized virus particles. Several important lessons learned from pressurized intraperitoneal aerosolized chemotherapy procedures are demonstrated to help improve our understanding and management. CONCLUSION: This paper evaluates the issues surrounding these challenges including the OR environment and AGPs which are germane to surgical practices around the world. Although there is no single universally agreed upon set of answers, we have presented what we think is a balanced cogent description of logical safe approaches to colorectal surgery during the COVID-19 pandemic.

Tissue Lignification, Cell Wall p-Coumaroylation and Degradability of Maize Stems Depend on Water Status.

Water supply and valorization are two urgent issues in the utilization of maize biomass in the context of climate change and replacement of fossil resources. Maximizing maize biomass valorization is of interest to make biofuel conversion competitive, and to increase forage energetic value for animal fodder. One way to estimate biomass valorization is to quantify cell wall degradability. In this study, we evaluated the impact of water supply on cell wall degradability, cell wall contents and structure, and distribution of lignified cell types in maize internodes using dedicated high-throughput tools to effectively phenotype maize internodes from 11 inbred lines under two contrasting irrigation scenarios in field trials over three years. Overall, our results clearly showed that water deficit induced significant changes in lignin content and distribution along with a reduction in lignin p-coumaroylation, thereby impacting cell wall degradability. Additionally, we also observed that responses to a water deficit varied between the lines examined, underscoring biochemical and histological target traits for plant breeding.

Pressurized intraperitoneal aerosol chemotherapy with oxaliplatin in colorectal peritoneal metastasis.

AIM: Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is an experimental drug delivery method that applies chemotherapy into the abdominal cavity as an aerosol under pressure. We present the first results obtained with PIPAC in colorectal peritoneal metastasis (CPM). METHOD: This is a retrospective analysis. PIPAC was applied in 17 consecutive patients with pretreated CPM. All patients had previously undergone surgery, and 16 had undergone previous lines of systemic chemotherapy (median, two lines). The mean peritoneal metastasis index (peritoneal cancer index) was 16 ± 10. Forty-eight applications of PIPAC with oxaliplatin (92 mg/m2 ) were given every 6 weeks at 37 °C and 12 mmHg for 30 min. The outcome criteria were microscopic pathological response, survival and adverse events according to Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. RESULTS: Forty-eight PIPAC administrations were performed with no intra-operative complications. The mean number of PIPAC administrations per patient was 2.8 (minimum one, maximum six). Postoperative adverse events (CTCAE level 3) were observed in four patients (23%), no CTCAE level-4 adverse events were reported. The hospital mortality was zero. Objective tumour responses were observed in 12/17 patients (71%), and the overall responses were as follows: complete pathological response (seven patients), major response (four patients), partial response (one patient), no response (two patients) and not eligible (three patients). The mean survival after first PIPAC was 15.7 months. CONCLUSION: Repeated PIPAC with oxaliplatin can induce the regression of pretreated CPM. The toxicity appears to be low. These preliminary results are encouraging and justify prospective clinical studies.

Quality of life of patients with end-stage peritoneal metastasis treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC).

BACKGROUND: Quality of Life (QoL) plays an important role in patients with peritoneal metastasis and is deteriorating continuously until death. Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an innovative palliative treatment of peritoneal metastasis. We present the first QoL results under PIPAC therapy. METHODS: Retrospective analysis of QLQ30 questionnaire results during repeated courses of PIPAC applications in palliative patients with pretreated peritoneal metastasis. RESULTS: 91 patients (M:F = 40:51, median age 64 (34-77) years) with 158 PIPAC applications were analyzed. 86% patients had previously received systemic chemotherapy. Peritoneal metastasis was advanced (Peritoneal Carcinomatosis Index I = 16 ± 10). At admission, only moderate impairment of functioning (62-83%) and symptom scores (17-47%) was observed. 48 patients received at least 2 PIPAC every 6 weeks. After PIPAC # 1, the global physical score deteriorated slightly (from 82% to 75%), but improved after PIPAC # 2 (up to 89%). Gastrointestinal symptoms (nausea/vomiting, constipation, diarrhoea, anorexia) remained stable under PIPAC therapy. CONCLUSIONS: Quality of life was relatively high in this group of patients with advanced, pretreated peritoneal metastasis, explaining their wish for further therapy. Functioning scores and disease-related symptoms were not altered for at least 3 months in the patients able to receive repeated PIPAC. Except for a transient moderate increase of pain scores, PIPAC did not cause therapy-related QoL deterioration, especially no gastrointestinal symptoms.

[Value of surgery in the palliative therapy for rectal cancer]. / Stellenwert der Chirurgie in der palliativen Behandlung des Rektumkarzinoms.

The treatment of advanced rectal cancer is a complicated task that can only poorly be reduced to the simple question "to operate or not to operate?" Instead the following factors must be taken into consideration: symptomatic versus non-symptomatic patients, emergency surgery versus elective surgery, proximal versus distal rectal cancer, local advanced versus metastatic disease, primary tumour versus recurrence, unresectable versus potentially resectable metastases, resection versus diversionary surgical procedures, etc. Also within the conservative group one must decide between interventional therapy (combined chemotherapy, stent placement, radiotherapy, etc.) and purely palliative therapy. Results from studies are not sufficient for the formulation of general recommendations. However, there are only few arguments against a surgical procedure in a symptomatic situation when the primary tumour dominates. In cases of metastasizing colorectal cancer modern chemotherapeutic procedures and new antibody therapies can markedly prolong survival. These results cannot be achieved by surgery alone. In this situation, it should be considered whether the longer life expectancy will be accompanied by the later occurrence of symptoms, which again justifies a surgical indication within the framework of multimodality therapy. The widely differing starting situations lead to different therapeutic approaches so that an individual indication can be made in the course of a tumour board discussion.

Key genes in lung cancer translational research: a meta-analysis.

In lung cancer, integrating translational data from various histologies obtained in different patients under different conditions can increase their robustness. This is a meta-analysis of cDNA array data obtained in 688 tumor patients (541 non-small cell lung cancer, 33 small cell lung cancer and 114 others) and 205 controls. 1,206 genes were found to be dysregulated in one of the 12 transcriptomics studies available. 748 results (62%) were obtained only once and might be questioned. 38% of observations could be reproduced twice or more. 346 genes were reported twice, 80 three times, 27 four and 5 five times. A common set of genes dysregulated in lung cancer was obtained, including BPA1, DUSP6, ASCL1, RNAS1 and S100P. p63 and CK 5/6 p63 are useful for differentiating adenocarcinoma and small cell lung cancer from squamous cell carcinoma. TFF-3 and MUC1 are over-expressed in adenocarcinoma. INSM1, SGNE1 and H2AFZ are typical for small cell lung cancer. Using a meta-analysis approach, it was possible to detect a robust set of genes differentially expressed in lung cancer and to determine a limited number of key genes linked to subtypes in lung cancer molecular pathology.

Changing molecular epidemiology of methicillin-resistant Staphylococcus aureus in a small geographic area over an eight-year period.

The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) at an international level shows that most MRSA strains belong to a few pandemic clones. At the local level, a predominance of one or two clones was generally reported. However, the situation is evolving and new clones are emerging worldwide, some of them with specific biological characteristics, such as the presence of Panton-Valentine leucocidin (PVL). Understanding these changes at the local and international levels is of great importance. Our objective was to analyze the evolution of MRSA epidemiology at multiple sites on a local level (Western Switzerland) over a period of 8 years. Data were based on MRSA reports from seven sentinel laboratories and infection control programs covering different areas. Pulsed-field gel electrophoresis was used to type MRSA isolates. From 1997 to 2004, a total of 2,256 patients with MRSA were reported. Results showed the presence of four predominant clones (accounting for 86% of patients), which could be related to known international clones (Berlin, New York/Japan, Southern Germany, and Iberian clones). Within the small geographic region, the 8-year follow-up period in the different areas showed spacio-temporal differences in the relative proportions of the four clones. Other international MRSA clones, as well as clones showing genetic characteristics identical to those of community-acquired MRSA (SCCmec type IV and the presence of PVL genes), were also identified but presumably did not disseminate. Despite the worldwide predominance of a few MRSA clones, our data showed that at a local level, the epidemiology of MRSA might be different from one hospital to another. Moreover, MRSA clones were replaced by other emerging clones, suggesting a rapid change.

Proteomics in cancer.

Proteomic studies have generated numerous datasets of potential diagnostic, prognostic, and therapeutic significance in human cancer. Two key technologies underpinning these studies in cancer tissue are two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS). Although surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF)-MS is the mainstay for serum or plasma analysis, other methods including isotope-coded affinity tag technology, reverse-phase protein arrays, and antibody microarrays are emerging as alternative proteomic technologies. Because there is little overlap between studies conducted with these approaches, confirmation of these advanced technologies remains an elusive goal. This problem is further exacerbated by lack of uniform patient inclusion and exclusion criteria, low patient numbers, poor supporting clinical data, absence of standardized sample preparation, and limited analytical reproducibility (in particular of 2D-PAGE). Despite these problems, there is little doubt that the proteomic approach has the potential to identify novel diagnostic biomarkers in cancer. In therapeutic proteomics, the challenge is significant due to the complexity systems under investigation (i.e., cells generate over 10(5) different polypeptides). However, the most significant contribution of therapeutic proteomics research is expected to derive not from single experiments, but from the synthesis and comparison of large datasets obtained under different conditions (e.g., normal, inflammation, cancer) and in different tissues and organs. Thus, standardized processes for storing and retrieving data obtained with different technologies by different research groups will have to be developed. Shifting the emphasis of cancer proteomics from technology development and data generation to careful study design, data organization, formatting, and mining is crucial to answer clinical questions in cancer research.

Is the movement-evoked potential mandatory for movement execution? A high-resolution EEG study in a deafferented patient.

During simple self-paced index finger flexion with and without visual feedback of the finger, we compared the movement-evoked potentials of the completely deafferented patient GL with those of 7 age-matched healthy subjects. EEG was recorded from 58 scalp positions, together with the electromyogram (EMG) from the first dorsal interosseous muscle and the movement trace. We analyzed the movement parameters and the contralateral movement-evoked potential and its source. The patient performed the voluntary movements almost as well as the controls in spite of her lack of sensory information from the periphery. In contrast, the movement-evoked potential was observed only in the controls and not in the patient. These findings clearly demonstrate that the movement-evoked potential reflects cutaneous and proprioceptive feedback from the moving part of the body. They also indicate that in absence of sensory peripheral input the motor control switches from an internal "sensory feedback-driven" to a "feedforward" mode. The role of the sensory feedback in updating the internal models and of the movement-evoked potential as a possible cortical correlate of motor awareness is discussed.

[Options for quality improvement in the treatment of rectum carcinoma]. / Möglichkeiten der Qualitätsverbesserung bei der Therapie des Rektumkarzinoms.

By means of a prospective multi centre study, 13 419 cases of surgically treated patients with rectum carcinomas were registered between 1.1.2000 and 31.12.2003 and assessed in regard to possible problems concerning indications and operative procedures. Beside a high rate of non-local resective procedures in T1-low risk carcinomas, unnecessary extirpations in cases of tumour localisation over 8 cm from the anal verge were found. Tumours of the lower two-thirds of the rectum were treated by incomplete TME in 20 % of the patients. In addition, there seems to be too low a rate of neo-adjuvant therapy procedures. Protective stomata were frequently foregone after low anterior resection. Endoscopic interventional methods were still used reluctantly in inoperable situations.