Quantum jumps of light recording the birth and death of a photon in a cavity

A microscopic system under continuous observation exhibits at random times sudden jumps between its states. The detection of this essential quantum feature requires a quantum non-demolition (QND) measurement repeated many times during the system evolution. Quantum jumps of trapped massive particles (electrons, ions or molecules) have been observed, which is not the case of the jumps of light quanta. Usual photodetectors absorb light and are thus unable to detect the same photon twice. They must be replaced by a transparent counter 'seeing' photons without destroying them3. Moreover, the light has to be stored over a duration much longer than the QND detection time. We have fulfilled these challenging conditions and observed photon number quantum jumps. Microwave photons are stored in a superconducting cavity for times in the second range. They are repeatedly probed by a stream of non-absorbing atoms. An atom interferometer measures the atomic dipole phase shift induced by the non-resonant cavity field, so that the final atom state reveals directly the presence of a single photon in the cavity. Sequences of hundreds of atoms highly correlated in the same state, are interrupted by sudden state-switchings. These telegraphic signals record, for the first time, the birth, life and death of individual photons. Applying a similar QND procedure to mesoscopic fields with tens of photons opens new perspectives for the exploration of the quantum to classical boundary

Preclinical evaluation of the cardiac toxicity of HMR-1826, a novel prodrug of doxorubicin

Cardiotoxicity represents the major side-effect limiting the clinical use of anthracyclines, especially doxorubicin, in cancer chemotherapy. The use of non-toxic prodrugs, or of liposome-encapsulated drugs, allows a better targeting of the tumours and may, therefore, improve the tolerance to the treatment. Using the model of isolated perfused rat heart, we have evaluated the cardiotoxicity of a novel prodrug of doxorubicin, HMR-1826, which consists of the association of doxorubicin to glucuronic acid. We have compared the cardiac effects (developed pressure, contractility and relaxation of the left ventricle) induced by HMR-1826 to those induced by doxorubicin and Doxil, a liposomal form of doxorubicin. HMR-1826 was administered intravenously every other day for 11 days at doses of 50–200 mg kg−1 per injection while doxorubicin was administered according to the same protocol at doses of 1–3 mg kg−1 per injection. Doxorubicin strongly decreased the cardiac functional parameters at the doses of 2.5 and 3 mg kg−1 per injection. Doxil (3 mg kg−1) and HMR-1826 (50–150 mg kg−1) were largely devoid of cardiotoxicity. HMR-1826 only induced significant alterations of the cardiac function at the highest dose used (200 mg kg−1 per injection). These alterations were much lower than those of doxorubicin at 2.5 mg kg−1 per injection, despite similar general toxicity symptoms (weight loss, nose bleeding and diarrhoea) at these respective doses. Thus, HMR-1826 appeared about 100-fold less cardiotoxic than doxorubicin. © 1999 Cancer Research Campaig

Genetic Diversity, Recombination, and Divergence in Animal Associated Penicillium dipodomyis

Penicillium dipodomyis is thought to be an exclusively asexual fungus associated with Kangaroo Rats, Dipodomys species, and is unique among Penicillium species in growing at 37°C but producing no known toxins. Lack of recombination within P. dipodomyis would result in limited adaptive flexibility but possibly enhance local adaptation and host selection via maintenance of favourable genotypes. Here, analysis of DNA sequence data from five protein-coding genes shows that recombination occurs within P. dipodomyis on a small spatial scale. Furthermore, detection of mating-type alleles supports outcrossing and a sexual cycle in P. dipodomyis. P. dipodomyis was a weaker competitor in in vitro assays with other Penicillium species found in association with Kanagaroo rats. Bayesian species level analysis suggests that the P. dipodomyis lineage diverged from closely related species also found in cheek pouches of Kangaroo Rats and their stored seeds about 11 million years ago, a similar divergence time as Dipodomys from its sister rodent taxa

Dietary effects on multi-element composition of European eel (Anguilla anguilla) otoliths

Otolith microchemistry is widely used as a tool to track individual migration pathways of diadromous fish under the assumption that the elemental composition of fish otoliths is directly influenced by the physicochemical properties of the surrounding water. Nevertheless, several endogenous factors are reported to affect element incorporation into fish otoliths and might lead to misinterpretations of migration studies. This study experimentally examined the influence of eight different diets on the microchemical composition of European eel (Anguilla anguilla) otoliths using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Seven natural prey types and one artificial diet were fed during 8 weeks in freshwater circuits. Results show for the first time that food has no significant influence on the incorporation of Na, Sr, Ba, Mg, Mn, Cu and Y into European eel otoliths. This indicates that the incorporation of elements usually chosen for migration studies is not affected by diet and that individual feeding behaviour of A. anguilla will not lead to any misinterpretation of migration pathways

Phase II study of single agent capecitabine in the treatment of metastatic non-pancreatic neuroendocrine tumours

BACKGROUND: This study sought to determine the safety of single agent capecitabine, a pro-drug of 5FU, in patients with metastatic non-pancreatic neuroendocrine tumours (NETs). METHODS: Multicentre phase II, first-line study design. Oral capecitabine was administered on days 1-14 of 3-week cycles. RESULTS: Treatment was safe and well tolerated. Common toxicities were diarrhoea and fatigue. CONCLUSION: The study provides evidence to support the use of capecitabine as a substitute for infusional 5FU in the management of NETs

Cimetidine in colorectal cancer – are the effects immunological or adhesion-mediated?

British Journal of Cancer (2002) 86, 159–160. DOI: 10.1038/sj/bjc/6600097 www.bjcancer.co

Analysis and comparison of very large metagenomes with fast clustering and functional annotation

<p>Abstract</p> <p>Background</p> <p>The remarkable advance of metagenomics presents significant new challenges in data analysis. Metagenomic datasets (metagenomes) are large collections of sequencing reads from anonymous species within particular environments. Computational analyses for very large metagenomes are extremely time-consuming, and there are often many novel sequences in these metagenomes that are not fully utilized. The number of available metagenomes is rapidly increasing, so fast and efficient metagenome comparison methods are in great demand.</p> <p>Results</p> <p>The new metagenomic data analysis method Rapid Analysis of Multiple Metagenomes with a Clustering and Annotation Pipeline (<b>RAMMCAP</b>) was developed using an ultra-fast sequence clustering algorithm, fast protein family annotation tools, and a novel statistical metagenome comparison method that employs a unique graphic interface. RAMMCAP processes extremely large datasets with only moderate computational effort. It identifies raw read clusters and protein clusters that may include novel gene families, and compares metagenomes using clusters or functional annotations calculated by RAMMCAP. In this study, RAMMCAP was applied to the two largest available metagenomic collections, the "Global Ocean Sampling" and the "Metagenomic Profiling of Nine Biomes".</p> <p>Conclusion</p> <p>RAMMCAP is a very fast method that can cluster and annotate one million metagenomic reads in only hundreds of CPU hours. It is available from <url>http://tools.camera.calit2.net/camera/rammcap/</url>.</p

Concurrent capecitabine and upper abdominal radiation therapy is well tolerated

We retrospectively evaluated acute toxicity in 88 patients that were treated with capecitabine and concurrent radiotherapy to the upper abdomen. These patients included 28 (32%) with pancreatic adenocarcinoma, 18 (20%) with cholangiocarcinoma, 11 (13%) with ampullary carcinoma, 11 (13%) with other primary tumors, 14 (16%) with liver metastases, and 6 (7%) with metastases at other sites. The median dose of radiotherapy was 45 Gy (range 30–72 Gy). The median dose of capecitabine was 850 mg/m(2 )twice daily, with 77% receiving 800–900 mg/m(2 )twice daily. The highest grade of acute toxicity was Common Terminology Criteria (CTC) grade 0 in 5 (6%), grade 1 in 60 (68%), grade 2 in 18 (20%), and grade 3 in 5 (6%) patients. No patient had CTC grade 4 toxicity. The most common grade 2 toxicities were nausea, hand-foot syndrome, fatigue, anorexia and diarrhea. The grade 3 toxicities included nausea, vomiting and fatigue. Three patients (3%) required hospitalization due to grade 3 acute toxicity. Capecitabine was interrupted, discontinued or given at an adjusted dose in 13 (15%) patients because of acute toxicity. Therefore, capecitabine and concurrent radiotherapy to the upper abdomen appears to be well tolerated. Capecitabine may serve as an alternative to bolus or infusional 5-FU during chemoradiation for upper gastrointestinal malignancies

The learning effect of intraoperative video-enhanced surgical procedure training

BACKGROUND: The transition from basic skills training in a skills lab to procedure training in the operating theater using the traditional master-apprentice model (MAM) lacks uniformity and efficiency. When the supervising surgeon performs parts of a procedure, training opportunities are lost. To minimize this intervention by the supervisor and maximize the actual operating time for the trainee, we created a new training method called INtraoperative Video-Enhanced Surgical Training (INVEST). METHODS: Ten surgical residents were trained in laparoscopic cholecystectomy either by the MAM or with INVEST. Each trainee performed six cholecystectomies that were objectively evaluated on an Objective Structured Assessment of Technical Skills (OSATS) global rating scale. Absolute and relative improvements during the training curriculum were compared between the groups. A questionnaire evaluated the trainee's opinion on this new training method. RESULTS: Skill improvement on the OSATS global rating scale was significantly greater for the trainees in the INVEST curriculum compared to the MAM, with mean absolute improvement 32.6 versus 14.0 points and mean relative improvement 59.1 versus 34.6% (P = 0.02). CONCLUSION: INVEST significantly enhances technical and procedural skill development during the early learning curve for laparoscopic cholecystectomy. Trainees were positive about the content and the idea of the curriculum