465 research outputs found

    Chronic cannulation in the small intestine of feral pigeons (Columba livia) to assess bioavailability

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    We improved a method of chronic duodenal cannulation to study intestinal transport of solutes in an in vivo model (pigeon, Columba livia). A hypoallergenic cannula was inserted into the proximal part of the small intestine of pigeons and used for solution administration. Recovery from surgery was extremely rapid and animals started eating and drinking within a day. After surgery, the body mass of cannulated pigeons was stable, and no adverse effects in the weight could be detected. The method is simple, economical and useful to determine intestinal bioavailability of solutes, for nutritional and ecological studies, in intact animals without influence of anesthesia.Fil: Chediack, Juan Gabriel. Universidad Nacional de San Luis. Facultad de Ciencias Humanas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; ArgentinaFil: Cid, Fabricio Damian. Universidad Nacional de San Luis. Facultad de Ciencias Humanas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; ArgentinaFil: Fasulo, S. V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Humanas; ArgentinaFil: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Humanas; Argentina. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentin

    Annual variation in the levels of transcripts of sex-specific genes in the mantle of the common mussel, Mytilus edulis

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    Mytilus species are used as sentinels for the assessment of environmental health but sex or stage in the reproduction cycle is rarely considered even though both parameters are likely to influence responses to pollution. We have validated the use of a qPCR assay for sex identification and related the levels of transcripts to the reproductive cycle. A temporal study of mantle of Mytilus edulis found transcripts of male-specific vitelline coat lysin (VCL) and female-specific vitelline envelope receptor for lysin (VERL) could identify sex over a complete year. The levels of VCL/VERL were proportional to the numbers of sperm/ova and are indicative of the stage of the reproductive cycle. Maximal levels of VCL and VERL were found in February 2009 declining to minima between July - August before increasing and re-attaining a peak in February 2010. Water temperature may influence these transitions since they coincide with minimal water temperature in February and maximal temperature in August. An identical pattern of variation was found for a cryptic female-specific transcript (H5) but a very different pattern was observed for oestrogen receptor 2 (ER2). ER2 varied in a sex-specific way with male > female for most of the cycle, with a female maxima in July and a male maxima in December. Using artificially spawned animals, the transcripts for VCL, VERL and H5 were shown to be present in gametes and thus their disappearance from mantle is indicative of spawning. VCL and VERL are present at equivalent levels in February and July-August but during gametogenesis (August to January) and spawning (March to June) VCL is present at lower relative amounts than VERL. This may indicate sex-specific control mechanisms for these processes and highlight a potential pressure point leading to reduced reproductive output if environmental factors cause asynchrony to gamete maturation or release

    Biological effects of PAHs and heavy metals in Mytilus galloprovincialis: Assessment of the petrochemical industry in the Sicilian Coast, Italy

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    The use of biomarkers to analyze the effects of exposure to chemical contaminants in the aquatic environment is more extended nowadays. Mussels are sedentary filter-feeding organisms which may be exposed to large amounts of chemical pollutants. Mussels are prone to bioaccumulation and magnification of contaminants. In the present work, biological effects of environmental pollution were evaluated, mainly related to presence of PAHs and heavy metals, through several antioxidants and detoxification biomarkers in mussels (Mytilus galloprovincialis) from three areas located in the Eastern coastline of Sicily (Italy), previously transplanted (active biomonitoring). One of these three areas corresponds to the industrial harbour area between Augusta and Priolo, considered one of the most extensive areas of petrochemical industrial activity in Europe, severely contaminated by PAHs and heavy metals; a second point is located in Brucoli, littoral zone where the presence of xenobiotics in the environment is considered negligible; and a third point (reference site) from which proceed the pristine population of M. galloprovincialis. Changes at molecular and biochemical level in the tissue of the digestive gland were quantified. The results showed a significant increase (p<0.05) in the activity of the antioxidant enzyme catalase, the activity and expression of the detoxifying enzyme glutathione-S-transferase, and malondialdehyde levels, as a marker of lipid peroxidation, in mussels from the area of Priolo. The metallothioneins (MTs) gene expression was significantly induced in mussels (p<0.05) from Priolo when compared to those from the reference site. AChE was negatively affected by pollutants evidencing a decreased activity in Priolo (p<0.05). No significant differences were observed between the three sampling sites in the expression of the CYP3A1. In conclusion, the observed results demonstrate that the pollution associated with petrochemical industrial area (mainly of PAHs and heavy metals) causes the activation of the detoxification and antioxidant defence systems in the digestive gland of the mussels M. galloprovincialis, indicative of oxidative stress. This study provides further evidence of the criticality representing harbour areas, due to the presence of xenobiotics in high concentrations, which can accumulate in sediments and in living organisms due to the limited hydrodynamic inside harbour

    Comparative study of haematology of two teleost fish (Mugil cephalus and Carassius auratus) from different environments and feeding habits

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    Haematological parameters are valuable indicators of fish health status. This study is aimed to provide baseline data of the blood profile of two teleost fish species living in different environments and with divergent feeding behaviour, namely the flathead grey mullet Mugil cephalus Linnaeus, 1758, a marine herbivorous fish, and the goldfish Carassius auratus (Linnaeus, 1758), a freshwater omnivorous fish. Using an automated system coupled with flow cytometry and light microscopy, significant variations were found between M. cephalus and C. auratus blood parameters, except for haemoglobin concentration (Hgb). A significant increase in red blood cell count (RBC) and haematocrit (Hct) levels, associated with reduced mean corpuscular volume (MCV), was revealed in mullets in respect to goldfish. These data may be attributable to differences in fish species, or to their divergent physiological activeness as high RBC values are associated with fast movement and high activity with streamlined bodies, or to environmental factors such as water salinity, an increase in which may lead to erythropoiesis as an adaptive process in seawater fish. Additionally, lower values of white blood cell count (WBC) and thrombocyte count (TC) were recorded in mullets with respect to goldfish, and these changes may be due to divergent feeding habits of the two fish species, or to their different environments since increased salinity may inversely affect WBC. Overall, findings from this study provide a better understanding of the influences of divergent environmental conditions and feeding habits on fish blood parameters. The combined use of an automatic haematological count with flow cytometry was demonstrated to be effective for an early assessment of blood parameters in different fish species

    Endoscopic Submucosal Dissection (ESD) for the Management of Fibrotic Non-Lifting Colorectal Lesions (NLCLs): Results from a Large Multicenter Retrospective Study

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    : Background/Objectives: The management of non-lifting colorectal lesions (NLCLs), often resulting from previous unsuccessful treatments or biopsies, remains challenging due to submucosal fibrosis that prevents adequate lifting. Endoscopic submucosal dissection (ESD) is a viable option for achieving complete resection in such cases. However, when standard ESD is not feasible, conversion to hybrid ESD (H-ESD) has been proposed as a rescue strategy. This study aimed to assess ESD's feasibility, effectiveness, and safety for NLCLs, including cases requiring conversion to H-ESD, when performed by experienced endoscopists in tertiary referral centers. Methods: In this multicenter retrospective study, data from patients with NLCLs treated by ESD/H-ESD between January 2009 and September 2022 were analyzed. The primary endpoint was the recurrence rate (RR). Secondary endpoints included the adverse event (AE) rate, technical success (TS) rate (en bloc resection regardless of technique), complete resection (CR), curative resection (cR) rates, and surgical intervention rate. Predictors of ESD technical success were identified. Results: In total, 178 patients with NLCLs were included (52 previously biopsied, 126 recurrent after previous resection). ESD was used in 111 (62.4%) and H-ESD in 67 (37.6%) cases. During a median follow-up of 373 days (IQR 540), the overall RR was 3.6%. The overall AE rate was 13.4%, and perforation was the most frequent (8.4%). All AEs were successfully managed endoscopically. The TS rate was 71.9%, significantly higher in previously biopsied lesions compared to recurrent ones (78.8% vs. 55.6%, p = 0.04). On multivariate analysis, rectal location (p &lt; 0.001), F1 fibrosis (p = 0.026), and previously biopsied lesions (p = 0.006) predicted ESD TS without the need for conversion to H-ESD. Conclusions: ESD/H-ESD is feasible and safe for NLCLs when performed by experienced operators, with low RR amenable to endoscopic treatment. Previously biopsied lesions, rectal location, and low fibrosis predict ESD TS

    The Endoscopic Management of Zenker’s Diverticulum: A Comprehensive Review

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    Zenker’s Diverticulum (ZD) is the most common hypopharyngeal diverticulum; however, it is often underdiagnosed. It results from the herniation of the mucosa and submucosa through Killian’s Triangle. Dysphagia is the primary symptom, occurring in 80–90% of cases. The primary goal of treatment is to transect the cricopharyngeal muscle (CM) and connect the ZD cavity to the esophageal lumen. Traditional treatments include surgical open transcervical diverticulectomy and CM septomyotomy, using rigid or flexible endoscopes. However, surgery is burdened by technical difficulties and not negligible rates of adverse events (AEs). For this reason, endoscopic techniques for ZD treatment have gained traction in recent years. Flexible endoscopic septum division (FESD), introduced nearly 20 years ago, involves a full-thickness incision of the diverticular septum. The advent of third-space endoscopy has led to the application of these techniques to ZD treatment as well. Zenker-POEM (Z-POEM) and, subsequently, Per Oral Endoscopic Septomyotomy (POES) have been developed. Hybrid techniques, such as Peroral Endoscopic Diverticulotomy (POED) and tunneling-free methods, represent additional ZD treatment options. This review outlines the armamentarium of ZD endoscopic management, summarizing the characteristics of these techniques, their benefits and limitations, and highlighting future research directions
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