70 research outputs found

    Commercial fisheries in a mega unregulated floodplain river: assessment of the most favourable hydrological conditions for its preservation

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    This paper deals with the hydrological variability effects on the primary commercial fish species inhabiting the main channel and the floodplain of the large Paraná River in its middle reaches in Argentina. Analysing more than eight decades (1935–2016) of information on the most frequent and abundant commercial species in conjunction with hydrological levels and temperature, our results show that spring–summer floods of a certain magnitude (c. 6 m) and durations (> 80 days) are crucial for sustaining commercial fisheries. Moreover, the frequency of these floods was modulated by the decadal climatic fluctuations that have occurred over the past 100 years in the Paraná Basin. An insight into the probable incidence of some anthropogenic influences is also provided.Fil: Rabuffetti, Ana Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Abrial, Elie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Blettler, Martin Cesar Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Eurich, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Eberle Folmer, Eliana Gisel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

    Radial Distribution of the Dust Comae of Comets 45P/Honda–Mrkos–Pajdusáková and 46P/Wirtanen

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    There was an unprecedented opportunity to study the inner dust coma environments, where the dust and gas are not entirely decoupled, of comets 45P/Honda–Mrkos–Pajdusáková (45P/HMP) from 2016 December 26 to 2017 March 15, and 46P/Wirtanen from 2018 November 10 to 2019 February 13, both in visible wavelengths. The radial profile slopes of these comets were measured in the R and HB-BC filters most representative of dust, and deviations from a radially expanding coma were identified as significant. The azimuthally averaged radial profile slope of comet 45P/HMP gradually changes from −1.81 ± 0.20 at 5.24 days preperihelion to −0.35 ± 0.16 at 74.41 days postperihelion. Contrastingly, the radial profile slope of 46P/Wirtanen stays fairly constant over the observed time period at −1.05 ± 0.05. Additionally, we find that the radial profile of 46P/Wirtanen is azimuthally dependent on the sky-plane-projected solar position angle, while that of 45P/HMP is not. These results suggest that comets 45P/HMP and 46P/Wirtanen have vastly different coma dust environments and that their dust expansion properties are distinct. As evident from these two comets, well-resolved inner comae are vital for detailed characterization of dust environments. © 2022. The Author(s). Published by the American Astronomical Society.We would like to thank everyone who participated in the data-gathering process. This includes all students from the Lunar and Planetary Laboratory course PTYS 495B/595B (Fall 2018). We would also like to thank the additional organizers of the 4*P Campaign: Matthew Knight (United States Naval Academy) and Tony Farnham (University of Maryland). We would like the thank the Steward Observatory technical staff for the amount of time they dedicated to this project. Finally, we would like to thank the SSO grant No. NNX16A670G (Walt Harris) and the NESSF grant No. 80NSSC18K1241 (Cassandra Lejoly; P.I.: Walt Harris) for allowing this work to be completed. We would also like to thank the Slovak Academy of Sciences grant No. VEGA 2/ 0023/18 (Oleksandra Ivanova) and the Slovak Research and Development Agency under the Contract no. APVV-19-0072 (Oleksandra Ivanova)

    Helicobacter pylori Perturbs Iron Trafficking in the Epithelium to Grow on the Cell Surface

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    Helicobacter pylori (Hp) injects the CagA effector protein into host epithelial cells and induces growth factor-like signaling, perturbs cell-cell junctions, and alters host cell polarity. This enables Hp to grow as microcolonies adhered to the host cell surface even in conditions that do not support growth of free-swimming bacteria. We hypothesized that CagA alters host cell physiology to allow Hp to obtain specific nutrients from or across the epithelial barrier. Using a polarized epithelium model system, we find that isogenic ΔcagA mutants are defective in cell surface microcolony formation, but exogenous addition of iron to the apical medium partially rescues this defect, suggesting that one of CagA's effects on host cells is to facilitate iron acquisition from the host. Hp adhered to the apical epithelial surface increase basolateral uptake of transferrin and induce its transcytosis in a CagA-dependent manner. Both CagA and VacA contribute to the perturbation of transferrin recycling, since VacA is involved in apical mislocalization of the transferrin receptor to sites of bacterial attachment. To determine if the transferrin recycling pathway is involved in Hp colonization of the cell surface, we silenced transferrin receptor expression during infection. This resulted in a reduced ability of Hp to colonize the polarized epithelium. To test whether CagA is important in promoting iron acquisition in vivo, we compared colonization of Hp in iron-replete vs. iron-deficient Mongolian gerbils. While wild type Hp and ΔcagA mutants colonized iron-replete gerbils at similar levels, ΔcagA mutants are markedly impaired in colonizing iron-deficient gerbils. Our study indicates that CagA and VacA act in concert to usurp the polarized process of host cell iron uptake, allowing Hp to use the cell surface as a replicative niche

    Helicobacter pylori Counteracts the Apoptotic Action of Its VacA Toxin by Injecting the CagA Protein into Gastric Epithelial Cells

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    Infection with Helicobacter pylori is responsible for gastritis and gastroduodenal ulcers but is also a high risk factor for the development of gastric adenocarcinoma and lymphoma. The most pathogenic H. pylori strains (i.e., the so-called type I strains) associate the CagA virulence protein with an active VacA cytotoxin but the rationale for this association is unknown. CagA, directly injected by the bacterium into colonized epithelium via a type IV secretion system, leads to cellular morphological, anti-apoptotic and proinflammatory effects responsible in the long-term (years or decades) for ulcer and cancer. VacA, via pinocytosis and intracellular trafficking, induces epithelial cell apoptosis and vacuolation. Using human gastric epithelial cells in culture transfected with cDNA encoding for either the wild-type 38 kDa C-terminal signaling domain of CagA or its non-tyrosine-phosphorylatable mutant form, we found that, depending on tyrosine-phosphorylation by host kinases, CagA inhibited VacA-induced apoptosis by two complementary mechanisms. Tyrosine-phosphorylated CagA prevented pinocytosed VacA to reach its target intracellular compartments. Unphosphorylated CagA triggered an anti-apoptotic activity blocking VacA-induced apoptosis at the mitochondrial level without affecting the intracellular trafficking of the toxin. Assaying the level of apoptosis of gastric epithelial cells infected with wild-type CagA+/VacA+ H. pylori or isogenic mutants lacking of either CagA or VacA, we confirmed the results obtained in cells transfected with the CagA C-ter constructions showing that CagA antagonizes VacA-induced apoptosis. VacA toxin plays a role during H. pylori stomach colonization. However, once bacteria have colonized the gastric niche, the apoptotic action of VacA might be detrimental for the survival of H. pylori adherent to the mucosa. CagA association with VacA is thus a novel, highly ingenious microbial strategy to locally protect its ecological niche against a bacterial virulence factor, with however detrimental consequences for the human host

    Enithelioid hemangioendothelioma, an ultra-rare cancer : a consensus paper from the community of experts

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    Epithelioid hemangioendothelioma (EHE) is an ultra-rare, translocated, vascular sarcoma. EHE clinical behavior is variable, ranging from that of a low-grade malignancy to that of a high-grade sarcoma and it is marked by a high propensity for systemic involvement. No active systemic agents are currently approved specifically for EHE, which is typically refractory to the antitumor drugs used in sarcomas. The degree of uncertainty in selecting the most appropriate therapy for EHE patients and the lack of guidelines on the clinical management of the disease make the adoption of new treatments inconsistent across the world, resulting in suboptimal outcomes for many EHE patients. To address the shortcoming, a global consensus meeting was organized in December 2020 under the umbrella of the European Society for Medical Oncology (ESMO) involving >80 experts from several disciplines from Europe, North America and Asia, together with a patient representative from the EHE Group, a global, disease-specific patient advocacy group, and Sarcoma Patient EuroNet (SPAEN). The meeting was aimed at defining, by consensus, evidence-based best practices for the optimal approach to primary and metastatic EHE. The consensus achieved during that meeting is the subject of the present publication.Peer reviewe

    Laparoscopic right hemicolectomy: a SICE (Società Italiana di Chirurgia Endoscopica e Nuove tecnologie) network prospective study on the approach to right colon lymphadenectomy in Italy: is there a standard?—CoDIG 2 (ColonDx Italian Group)

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    Background: Colon cancer is a disease with a worldwide spread. Surgery is the best option for the treatment of advanced colon cancer, but some aspects are still debated, such as the extent of lymphadenectomy. In Japanese guidelines, the gold standard was D3 dissection to remove the central lymph nodes (203, 213, and 223), but in 2009, Hoenberger et al. introduced the concept of complete mesocolic excision, in which surgical dissection follows the embryological planes to remove the mesentery entirely to prevent leakage of cancer cells and collect more lymph nodes. Our study describes how lymphadenectomy is currently performed in major Italian centers with an unclear indication on the type of lymphadenectomy that should be performed during right hemicolectomy (RH). Methods: CoDIG 2 is an observational multicenter national study that involves 76 Italian general surgery wards highly specialized in colorectal surgery. Each center was asked not to modify their usual surgical and clinical practices. The aim of the study was to assess the preference of Italian surgeons on the type of lymphadenectomy to perform during RH and the rise of any new trends or modifications in habits compared to the findings of the CoDIG 1 study conducted 4 years ago. Results: A total of 788 patients were enrolled. The most commonly used surgical technique was laparoscopic (82.1%) with intracorporeal (73.4%), side-to-side (98.7%), or isoperistaltic (96.0%) anastomosis. The lymph nodes at the origin of the vessels were harvested in an inferior number of cases (203, 213, and 223: 42.4%, 31.1%, and 20.3%, respectively). A comparison between CoDIG 1 and CoDIG 2 showed a stable trend in surgical techniques and complications, with an increase in the robotic approach (7.7% vs. 12.3%). Conclusions: This analysis shows how lymphadenectomy is performed in Italy to achieve oncological outcomes in RH, although the technique to achieve a higher lymph node count has not yet been standardized. Trial registration (ClinicalTrials.gov) ID: NCT05943951

    Laparoscopic right hemicolectomy: the SICE (Societ\ue0 Italiana di Chirurgia Endoscopica e Nuove Tecnologie) network prospective trial on 1225 cases comparing intra corporeal versus extra corporeal ileo-colic side-to-side anastomosis

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    Background: While laparoscopic approach for right hemicolectomy (LRH) is considered appropriate for the surgical treatment of both malignant and benign diseases of right colon, there is still debate about how to perform the ileo-colic anastomosis. The ColonDxItalianGroup (CoDIG) was designed as a cohort, observational, prospective, multi-center national study with the aims of evaluating the surgeons\u2019 attitude regarding the intracorporeal (ICA) or extra-corporeal (ECA) anastomotic technique and the related surgical outcomes. Methods: One hundred and twenty-five Surgical Units experienced in colorectal and advanced laparoscopic surgery were invited and 85 of them joined the study. Each center was asked not to change its surgical habits. Data about demographic characteristics, surgical technique and postoperative outcomes were collected through the official SICE website database. One thousand two hundred and twenty-five patients were enrolled between March 2018 and September 2018. Results: ICA was performed in 70.4% of cases, ECA in 29.6%. Isoperistaltic anastomosis was completed in 85.6%, stapled in 87.9%. Hand-sewn enterotomy closure was adopted in 86%. Postoperative complications were reported in 35.4% for ICA and 50.7% for ECA; no significant difference was found according to patients\u2019 characteristics and technologies used. Median hospital stay was significantly shorter for ICA (7.3 vs. 9 POD). Postoperative pain in patients not prescribed opioids was significantly lower in ICA group. Conclusions: In our survey, a side-to-side isoperistaltic stapled ICA with hand-sewn enterotomy closure is the most frequently adopted technique to perform ileo-colic anastomosis after any indications for elective LRH. According to literature, our study confirmed better short-term outcomes for ICA, with reduction of hospital stay and postoperative pain. Trial registration: Clinical trial (Identifier: NCT03934151)

    Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

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    Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk
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