Are Laparoscopic Staplers Effective for Ligation of Large Intraabdominal Arteries?

AbstractObjectives. To evaluate ligation of aortoiliac arteries with laparoscopic staplers in order to develop specifically designed staplers.Methods. Cadaveric study. Seven human cadaver aortas were stapled using EndoGIA60® staplers. Efficiency was evaluated macroscopically and on a hydrodynamic bench.Clinical study. Twelve patients had ligation of 14 large abdominal arteries (aorta: nine, iliac artery: four, hepatic artery: one) using a laparoscopic stapler. Stapling efficiency was judged on peroperative clinical and postoperative CT scan criteria.Results. Cadaveric study. Stapling was performed perfectly on four moderately calcified aortas, without leakage with a pulsatile pressure of >250 mmHg. For three aortas with severe calcification, stapling was not efficient and major leakage occurred.Clinical study. Stapling appeared clinically efficient on all arteries but one aorta: this severely calcified aorta was ligated conventionally. The staplers are not easy to use due to their shape and their lack of articulation. After a mean follow-up of 31.3 months, all the other stapled arteries were effectively ligated.Conclusion. The commercially available staplers can be used securely on moderately calcified arteries but stapling of severely calcified arteries should be avoided. These devices should be redesigned to facilitate their use in vascular surgery

Multiproxy investigation of the last 2,000 years BP marine paleoenvironmental record along the western Spitsbergen margin

A reconstruction of the last 2,000 years BP of environmental and oceanographic changes on the western margin of Spitsbergen was performed using a multidisciplinary approach including the fossil assemblages of diatoms, planktic and benthic foraminifera and calcareous nannofossils and the use of geochemistry (X-ray fluorescence spectroscopy, X-ray diffraction). We identified two warm periods (2,000–1,600 years BP and 1,300–700 years BP) that were associated with the Roman Warm Period and the Medieval Warm Period that alternate with colder oceanic conditions and sea ice coverage occurred during the Dark Ages (1,600–1,300 years BP) and the beginning of the Little Ice Age. During the Medieval Warm Period the occurrence of ice-rafted debris and Aulocoseira spp., a specific diatom genus commonly associated with continental freshwater, suggests significant runoff of meltwaters from local glaciers

The analog signal processor of the Auger fluorescence detector prototype

The Auger Fluorescence Detector will allow to determine the longitudinal development of atmospheric showers in the range 10 19 –10 21 eV. A detector module comprises an array of 20 � 22 PMTs at the focal surface of a large-aperture telescope. Thirty such modules will be used. The PMTs pixel signal is variable in shape depending on the shower-eye geometry. The sky background light (BL) is also variable. We have developed an analog signal processor to obtain best energy and timing resolution despite those constrains. The Head Electronics (HE) bias the PMTs and keeps its pulsegain constant even for large BL. This is measured using a current-monitor of novel design. Both the signal pulse and the BL DC level are sent via a single twisted pair to the Analog Board (AB). The AB performs the compression of the 15–16 bit signal dynamic range into 12 bits of the FADC which follows the AB. A three-pole Bessel filter was adopted for antialiasing. The AB includes 16 bit sigma-delta chips to readout the BL DC level, and a test-pulse distribution system. # 2001 Elsevier Science B.V. All rights reserved. PACS: 29.4

Role of the p53/p21 system in the response of human colon carcinoma cells to Doxorubicin

BACKGROUND: Colon adenocarcinomas are refractory to a number of widely used anticancer agents. Multifactorial mechanisms have been implicated in this intrinsically resistant phenotype, including deregulation of cell death pathways. In this regard, the p53 protein has a well established role in the control of tumor cell response to DNA damaging agents; however, the relationship between p53-driven genes and drug sensitivity remains controversial. The present study investigates the role of the p53/p21 system in the response of human colon carcinoma cells to treatment with the cytotoxic agent doxorubicin (DOX) and the possibility to modify the therapeutic index of DOX by modulation of p53 and/or p21 protein levels. METHODS: The relationship between p53 and p21 protein levels and the cytotoxic effect of DOX was investigated, by MTT assay and western blot analysis, in HCT116 (p53-positive) and HT29 (p53-negative) colon cancer cells. We then assessed the effects of DOX in two isogenic cell lines derived from HCT116 by abrogating the expression and/or function of p53 and p21 (HCT116-E6 and HCT116 p21-/-, respectively). Finally, we evaluated the effect of pre-treatment with the piperidine nitroxide Tempol (TPL), an agent that was reported to induce p21 expression irrespective of p53 status, on the cytotoxicity of DOX in the four cell lines. Comparisons of IC50 values and apoptotic cell percentages were performed by ANOVA and Bonferroni's test for independent samples. C.I. calculations were performed by the combination Index method. RESULTS: Our results indicate that, in the colon carcinoma cell lines tested, sensitivity to DOX is associated with p21 upregulation upon drug exposure, and DOX cytotoxicity is potentiated by pre-treatment with TPL, but only in those cell lines in which p21 can be upregulated. CONCLUSIONS: p21 induction may significantly contribute to the response of colon adenocarcinomas cells to DOX treatment; and small molecules that can exploit p53-independent pathways for p21 induction, such as TPL, may find a place in chemotherapeutic protocols for the clinical management of colorectal cancer, where p53 function is often lost, due to genetic or epigenetic defects or to post-transcriptional inactivating mechanisms

Influence of Grain Boundary Character on Creep Void Formation in Alloy 617

Alloy 617, a high temperature creep-resistant, nickel-based alloy, is being considered for the primary heat exchanger for the Next Generation Nuclear Plant (NGNP) which will operate at temperatures exceeding 760oC. Orientation imaging microscopy (OIM) is used to characterize the grain boundaries in the vicinity of creep voids that develop during high temperature creep tests (800-1000oC at creep stresses ranging from 20-85 MPa) terminated at creep strains ranging from 5-40%. Observations using optical microscopy indicate creep rate does not significantly influence the creep void fraction at a given creep strain. Preliminary analysis of the OIM data indicates voids tend to form on grain boundaries parallel, perpendicular or 45o to the tensile axis, while few voids are found at intermediate inclinations to the tensile axis. Random grain boundaries intersect most voids while CSL-related grain boundaries did not appear to be consistently associated with void development

Significant loss of mitochondrial diversity within the last century due to extinction of peripheral populations in eastern gorillas

Species and populations are disappearing at an alarming rate as a direct result of human activities. Loss of genetic diversity associated with population decline directly impacts species' long-term survival. Therefore, preserving genetic diversity is of considerable conservation importance. However, to assist in conservation efforts, it is important to understand how genetic diversity is spatially distributed and how it changes due to anthropogenic pressures. In this study, we use historical museum and modern faecal samples of two critically endangered eastern gorilla taxa, Grauer's (Gorilla beringei graueri) and mountain gorillas (Gorilla beringei beringei), to directly infer temporal changes in genetic diversity within the last century. Using over 100 complete mitochondrial genomes, we observe a significant decline in haplotype and nucleotide diversity in Grauer's gorillas. By including historical samples from now extinct populations we show that this decline can be attributed to the loss of peripheral populations rather than a decrease in genetic diversity within the core range of the species. By directly quantifying genetic changes in the recent past, our study shows that human activities have severely impacted eastern gorilla genetic diversity within only four to five generations. This rapid loss calls for dedicated conservation actions, which should include preservation of the remaining peripheral populations.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Stat3 Mediates Expression of Autotaxin in Breast Cancer

We determined that signal transducer and activator of transcription 3 (Stat3) is tyrosine phosphorylated in 37% of primary breast tumors and 63% of paired metastatic axillary lymph nodes. Examination of the distribution of tyrosine phosphorylated (pStat3) in primary tumors revealed heterogenous expression within the tumor with the highest levels found in cells on the edge of tumors with relatively lower levels in the central portion of tumors. In order to determine Stat3 target genes that may be involved in migration and metastasis, we identified those genes that were differentially expressed in primary breast cancer samples as a function of pStat3 levels. In addition to known Stat3 transcriptional targets (Twist, Snail, Tenascin-C and IL-8), we identified ENPP2 as a novel Stat3 regulated gene, which encodes autotaxin (ATX), a secreted lysophospholipase which mediates mammary tumorigenesis and cancer cell migration. A positive correlation between nuclear pStat3 and ATX was determined by immunohistochemical analysis of primary breast cancer samples and matched axillary lymph nodes and in several breast cancer derived cell lines. Inhibition of pStat3 or reducing Stat3 expression led to a decrease in ATX levels and cell migration. An association between Stat3 and the ATX promoter, which contains a number of putative Stat3 binding sites, was determined by chromatin immunoprecipitation. These observations suggest that activated Stat3 may regulate the migration of breast cancer cells through the regulation of ATX

Specie esotiche invasive di rilevanza unionale in Italia: aggiornamenti e integrazioni

La Commissione Europea (CE) ha inserito ad oggi 36 taxa esotici vegetali nella lista delle specie esotiche invasive di rilevanza unionale ai sensi del Regolamento (UE) n. 1143/2014 del Parlamento Europeo e del Consiglio, recante disposizioni volte a prevenire e gestire l’introduzione e la diffusione delle specie esotiche invasive. La lista delle specie di rilevanza unionale viene periodicamente aggiornata e include quelle specie che rappresentano una grave minaccia per la biodiversità, ma anche per la salute dei cittadini e le attività economiche nei territori dell’Unione Europea e che necessitano di una gestione concertata a livello comunitario. La CE vigila sullo stato di ogni taxon grazie anche a periodiche rendicontazioni da parte dei paesi dell'Unione. In vista di tali report, tra il 2020 e il 2021 è stata definita e integrata la distribuzione di queste specie in Italia