El bivalvo de agua dulce Diplodon chilensis como herramienta para el estudio de ambientes acuáticos contaminados en Patagonia Norte.

El incremento en el vertido de efluentes cloacales hacia los cuerpos de agua, como producto de la expansión de las áreas urbanas, representa una amenaza tanto a nivel ecosistémico como sanitario. En particular, la cuenca del río Pocahullo, en la ciudad de San Martín de los Andes, se encuentra afectada por descargas de efluentes cloacales con y sin tratamiento, los cuales son transportados y vertidos finalmente en la margen este del lago Lacar. La búsqueda de biomarcadores que reflejen la calidad del agua y el desarrollo de estrategias de bioremediación, constituyen herramientas útiles para su implementación en programas de biomonitoreo y en políticas de restauración de ambientes contaminados. En este trabajo de tesis se evalúa el potencial de la almeja nativa Diplodon chilensis como especie centinela y bioremediadora en ambientes acuáticos contaminados por efluentes cloacales. Con este objetivo, se estudiaron sus respuestas fisiológicas concernientes al balance oxidativo, la respuesta inmune y la condición metabólica, como biomarcadores de exposición. Además, se evaluó la capacidad filtradora de la almeja sobre agua y sedimentos contaminados por este tipo de efluentes. Por otro lado y con fines de implementación en estrategias de bioremediación, se evaluó el potencial inmunoestimulante y antioxidante de la alimentación previa con Euglena gracilis en almejas expuestas a Escherichia coli en laboratorio y a contaminación por efluentes cloacales en la cuenca del río Pocahullo. Se utilizaron técnicas fisicoquímicas, bioquímicas, citológicas e histológicas. En el Capítulo I, se evalúa la capacidad de respuesta de biomarcadores en branquia y glándula digestiva de D. chilensis expuesto a contaminación por efluentes cloacales, a corto y largo plazo. Almejas recolectadas en una zona no contaminada en el Lago Lacar fueron trasplantadas en cajas a un sitio de referencia no contaminado y a otros dos sitios con contaminación cloacal creciente en la cuenca del río Pocahullo. Se evaluaron respuestas antioxidantes y/o detoxificantes, daño oxidativo y condición metabólica al primer y tercer mes de la exposición a campo. Luego, almejas aclimatadas a largo plazo (siete meses) en el sitio de mayor contaminación fueron expuestas de forma aguda (8 h) en el laboratorio a agua contaminada con aproximadamente el doble de concentración bacteriana que la medida en ese sitio al momento de la recolección. Las respuestas enzimáticas se evaluaron antes y después de la exposición aguda. Los resultados más relevantes de estos experimentos sugieren que las actividades enzimáticas glutatión S- transferasa y catalasa en branquia de D. chilensis son biomarcadores aplicables para la detección de contaminación por efluentes cloacales con altas concentraciones de coliformes fecales, independientemente de que los individuos sean previamente aclimatados o no. Además, la actividad catalasa en glándula digestiva es sensible al aumento agudo en la carga bacteriana, tanto en almejas previamente expuestas a contaminación como en almejas extraídas de sitios no contaminados, mientras que la enzima glutatión S- transferasa en glándula digestiva se torna sensible luego de la exposición a largo plazo. Complementariamente, se sugiere que los efectos de trasplante sobre las respuestas fisiológicas deberían ser correctamente monitoreados para evitar interpretaciones erróneas en estudios de campo. En el Capítulo II, se evalúa el estado fisiológico de almejas expuestas crónicamente a contaminación por efluentes cloacales en el lago Lacar. Con este fin, se recolectaron individuos de poblaciones naturales de D. chilensis en un sitio no contaminado y en el área del lago contaminada por efluentes cloacales en la desembocadura del río Pocahullo. Se estudiaron y compararon biomarcadores de respuesta inmune, balance oxidativo, daño a ADN, reservas energéticas, factores morfométricos y capacidad filtradora, junto con el potencial biorremediador, en ambos grupos. Los resultados de este estudio sugieren que D. chilensis modula sus respuestas fisiológicas ante la exposición crónica a contaminación por efluentes cloacales, favoreciendo respuestas inmunes celulares, como el número de hemocitos y la actividad fagocítica, y evitando efectos deletéreos en estas células. Sin embargo, en branquia se observa sensibilidad a estas condiciones, la cual se evidencia en cambios morfométricos y en daño a ADN. Por otro lado, la capacidad filtradora de D. chilensis no es afectada por la exposición crónica a contaminación por efluentes cloacales, destacándose su actividad bioremediadora en agua y sedimentos contaminados con bacterias entéricas. Finalmente, en el Capítulo III se evalúan y comparan los efectos de modulación ejercidos por la alimentación previa con E. gracilis sobre la respuesta inmune, el balance oxidativo y la condición metabólica de D. chilensis expuesto a E. coli en laboratorio, por 5 días y a contaminación por efluentes cloacales en la cuenca del río Pocahullo, por 10 días. Los resultados sugieren que E. gracilis constituye un potencial complemento dietario con propiedades protectoras y nutricionales para ser utilizado en estrategias de biorremediación con bivalvos filtradores. En general, en ambos casos se observa que la alimentación con E. gracilis favorece la respuesta inmune celular (fagocitosis, producción de especies reactivas de oxígeno) y la resistencia al daño en hemocitos (viabilidad, estabilidad de la membrana lisosomal), como así también la condición metabólica (síntesis de proteínas, crecimiento somático, masa de glándula digestiva) en esta almeja. Sin embargo, la dosis y el tiempo de administración requieren un mayor estudio, ya que la alimentación con E. gracilis por sí misma y bajo condiciones de ayuno o trasplante, puede comprometer el balance oxidativo en branquia y glándula digestiva.Sewage water discharges from growing urban areas constitute an ecosystemic and sanitary threat for aquatic environments and human health. Particularly, in San Martín de los Andes city, treated and untreated sewage water is discharged into the Pocahullo river basin, carried along the river course and finally released into the East cost of Lacar lake. Biomarkers for water quality assessment and bioremediation strategies are useful tools to be implemented in biomonitoring and restoration programs. In this thesis, the native mussel Diplodon chilensis is evaluated as a sentinel and bioremediator species in sewage polluted environments. Therefore, physiological responses related to oxidative balance, immune response and metabolic condition were evaluated in this mussel as biomarkers of exposure, while their filtering capacity was assessed for remediating sewage polluted water and sediments. In addition, immunostimulant and antioxidant potential of Euglena gracilis diet was evaluated in D. chilensis challenged with Escherichia coli in laboratory conditions and exposed to sewage polluted water in Pocahullo river basin. Physicochemical, biochemical, cytological and histological techniques were applied in this work. In Chapter I, biomarkers of response to short and long-term exposure to sewage polluted water were evaluated in gill and digestive gland of D. chilensis. Mussels from an unpolluted area in Lacar lake were caged at a reference site and at two sites with increasing sewage pollution in Pocahullo river basin. Antioxidant and detoxifying responses, along with oxidative damage and metabolic condition biomarkers were evaluated in the first and third month of field exposure. Then, mussels acclimated for seven months in the most polluted site were acutely exposed in laboratory (8 h) to sewage polluted water with a higher concentration of fecal bacteria than that measured in the site at the time of collection (aprox.[ ] x 2). Enzyme responses were evaluated before and after acute exposure. The results of these experiments suggest that glutathione S- transferase and catalase activities in gill of D. chilensis are suitable biomarkers for sewage pollution detection at high fecal bacteria concentrations, regardless of previous exposure history. In addition, catalase activity in digestive gland is sensitive to the acute increase in bacterial load, both in mussels previously exposed and in those from the reference site, while glutathione S- transferase activity becomes responsive after long-term acclimation. Complementary, transplantation effects on physiological variables should be accurately monitored in order to avoid data misinterpretation. In Chapter II, physiological status was evaluated in mussels chronically exposed to sewage water pollution in Lacar lake. Mussels were collected from natural populations of D. chilensis inhabiting an unpolluted site and the sewage polluted site next to Pocahullo river mouth. Biomarkers of immune response, oxidative balance, DNA damage, energetic reserves, morphometric factors and filtering capacity were evaluated in both groups, along with their bioremediation potential. The results of this study suggest that D. chilensis modulates physiological responses upon chronic exposure to sewage pollution, favoring cellular immune responses, such as hemocyte number and phagocytosis, and avoiding deleterious effects in these cells. However, gills are sensitive to these conditions, suffering morphometric changes and DNA damage. D. chilensis maintains its filtering capacity under chronic exposure to sewage pollution, showing bioremediation activity on bacteriological quality of polluted water and sediments. Finally, in Chapter III, the modulating effects of E. gracilis diet on immune response, oxidative balance and metabolic condition are evaluated and compared in D. chilensis challenged with E. coli in laboratory, for 5 days and exposed to sewage pollution in Pocahullo river basin, for 10 days. The results of these experiments suggest that E. gracilis is a potential dietary complement with protective and nutritional qualities for filtering bivalves used in bioremediation strategies. In general in both cases, E. gracilis diet favors immune cellular response (phagocytosis, ROS production) and damage resistance in hemocytes (viability, lisosomal membrane stability), as well as metabolic condition (protein synthesis, somatic growth, digestive gland mass). Nevertheless, doses and time of administration require further study, since E. gracilis diet may compromise oxidative balance in gill and digestive gland, under control, starvation and transplantation conditionsFil: Bianchi, Virginia A. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina

Radiomics and artificial intelligence in prostate cancer: new tools for molecular hybrid imaging and theragnostics

In prostate cancer (PCa), the use of new radiopharmaceuticals has improved the accuracy of diagnosis and staging, refined surveillance strategies, and introduced specific and personalized radioreceptor therapies. Nuclear medicine, therefore, holds great promise for improving the quality of life of PCa patients, through managing and processing a vast amount of molecular imaging data and beyond, using a multi-omics approach and improving patients' risk-stratification for tailored medicine. Artificial intelligence (AI) and radiomics may allow clinicians to improve the overall efficiency and accuracy of using these "big data" in both the diagnostic and theragnostic field: from technical aspects (such as semi-automatization of tumor segmentation, image reconstruction, and interpretation) to clinical outcomes, improving a deeper understanding of the molecular environment of PCa, refining personalized treatment strategies, and increasing the ability to predict the outcome. This systematic review aims to describe the current literature on AI and radiomics applied to molecular imaging of prostate cancer

Novel Phosphorylation Sites in the S. cerevisiae Cdc13 Protein Reveal New Targets for Telomere Length Regulation

The S. cerevisiae Cdc13 is a multifunctional protein with key roles in regulation of telomerase, telomere end protection, and conventional telomere replication, all of which are cell cycle-regulated processes. Given that phosphorylation is a key mechanism for regulating protein function, we identified sites of phosphorylation using nano liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS). We also determined phosphorylation abundance on both wild type (WT) and a telomerase deficient form of Cdc13, encoded by the cdc13-2 allele, in both G1 phase cells, when telomerase is not active, and G2/M phase cells, when it is. We identified 21 sites of in vivo phosphorylation, of which only five had been reported previously. In contrast, phosphorylation of two in vitro targets of the ATM-like Tel1 kinase, S249 and S255, was not detected. This result helps resolve conflicting data on the importance of phosphorylation of these residues in telomerase recruitment. multiple residues showed differences in their cell cycle pattern of modification. For example, phosphorylation of S314 was significantly higher in the G2/M compared to the G1 phase and in WT versus mutant Cdc13, and a S314D mutation negatively affected telomere length. Our findings provide new targets in a key telomerase regulatory protein for modulation of telomere dynamics. [Image: see text

Roles of Pif1-like helicases in the maintenance of genomic stability

The Pif1p family of DNA helicases is conserved from yeast to humans. To date, four members of this family have been analyzed in some detail by in vitro and in vivo assays: the two baker's yeast helicases, ScPif1p and Rrm3p, the fission yeast Pfh1p and the human enzyme hPif1p. In vitro, these enzymes are 5′ to 3′ DNA helicase and show little processivity. In vivo, ScPif1p, Rrm3p and probably Pfh1p, function in both the nucleus at specific genomic loci and in mitochondria, where they are needed for the stable maintenance of the genome as accessory helicases to the replication machinery. Interestingly, they act on common DNA substrates but appear to have largely non-overlapping cellular functions, ranging from Okazaki fragment processing, telomerase inhibition, to helping the replication fork progress through non-nucleosomal protein–DNA complexes. For example, both ScPif1p and Rrm3p affect the replication of telomeres, but in a different way: Pif1p inhibits telomerase-mediated telomere elongation by directly removing telomerase from a DNA end, whereas Rrm3p facilitates replication through telomeric DNA. Here we review the current knowledge on the Pif1-like helicases, as a first step towards understanding the basis of their functional specialization and mechanism of action

Two Pathways Recruit Telomerase to Saccharomyces cerevisiae Telomeres

The catalytic subunit of yeast telomerase, Est2p, is a telomere associated throughout most of the cell cycle, while the Est1p subunit binds only in late S/G2 phase, the time of telomerase action. Est2p binding in G1/early S phase requires a specific interaction between telomerase RNA (TLC1) and Ku80p. Here, we show that in four telomerase-deficient strains (cdc13-2, est1Ä, tlc1-SD, and tlc1-BD), Est2p telomere binding was normal in G1/early S phase but reduced to about 40–50% of wild type levels in late S/G2 phase. Est1p telomere association was low in all four strains. Wild type levels of Est2p telomere binding in late S/G2 phase was Est1p-dependent and required that Est1p be both telomere-bound and associated with a stem-bulge region in TLC1 RNA. In three telomerase-deficient strains in which Est1p is not Est2p-associated (tlc1-SD, tlc1-BD, and est2Ä), Est1p was present at normal levels but its telomere binding was very low. When the G1/early S phase and the late S/G2 phase telomerase recruitment pathways were both disrupted, neither Est2p nor Est1p was telomere-associated. We conclude that reduced levels of Est2p and low Est1p telomere binding in late S/G2 phase correlated with an est phenotype, while a WT level of Est2p binding in G1 was not sufficient to maintain telomeres. In addition, even though Cdc13p and Est1p interact by two hybrid, biochemical and genetic criteria, this interaction did not occur unless Est1p was Est2p-associated, suggesting that Est1p comes to the telomere only as part of the holoenzyme. Finally, the G1 and late S/G2 phase pathways for telomerase recruitment are distinct and are likely the only ones that bring telomerase to telomeres in wild-type cells

Functional characterization of a multi-cancer risk locus on chr5p15.33 reveals regulation of TERT by ZNF148

Genome wide association studies (GWAS) have mapped multiple independent cancer susceptibility loci to chr5p15.33. Here, we show that fine-mapping of pancreatic and testicular cancer GWAS within one of these loci (Region 2 in CLPTM1L) focuses the signal to nine highly correlated SNPs. Of these, rs36115365-C associated with increased pancreatic and testicular but decreased lung cancer and melanoma risk, and exhibited preferred protein-binding and enhanced regulatory activity. Transcriptional gene silencing of this regulatory element repressed TERT expression in an allele-specific manner. Proteomic analysis identifies allele-preferred binding of Zinc finger protein 148 (ZNF148) to rs36115365-C, further supported by binding of purified recombinant ZNF148. Knockdown of ZNF148 results in reduced TERT expression, telomerase activity and telomere length. Our results indicate that the association with chr5p15.33-Region 2 may be explained by rs36115365, a variant influencing TERT expression via ZNF148 in a manner consistent with elevated TERT in carriers of the C allele

Particulate matter exposure during pregnancy is associated with birth weight, but not gestational age, 1962-1992: a cohort study

<p>Abstract</p> <p>Background</p> <p>Exposure to air pollutants is suggested to adversely affect fetal growth, but the evidence remains inconsistent in relation to specific outcomes and exposure windows.</p> <p>Methods</p> <p>Using birth records from the two major maternity hospitals in Newcastle upon Tyne in northern England between 1961 and 1992, we constructed a database of all births to mothers resident within the city. Weekly black smoke exposure levels from routine data recorded at 20 air pollution monitoring stations were obtained and individual exposures were estimated via a two-stage modeling strategy, incorporating temporally and spatially varying covariates. Regression analyses, including 88,679 births, assessed potential associations between exposure to black smoke and birth weight, gestational age and birth weight standardized for gestational age and sex.</p> <p>Results</p> <p>Significant associations were seen between black smoke and both standardized and unstandardized birth weight, but not for gestational age when adjusted for potential confounders. Not all associations were linear. For an increase in whole pregnancy black smoke exposure, from the 1^st(7.4 μg/m³) to the 25^th(17.2 μg/m³), 50^th(33.8 μg/m³), 75^th(108.3 μg/m³), and 90^th(180.8 μg/m³) percentiles, the adjusted estimated decreases in birth weight were 33 g (SE 1.05), 62 g (1.63), 98 g (2.26) and 109 g (2.44) respectively. A significant interaction was observed between socio-economic deprivation and black smoke on both standardized and unstandardized birth weight with increasing effects of black smoke in reducing birth weight seen with increasing socio-economic disadvantage.</p> <p>Conclusions</p> <p>The findings of this study progress the hypothesis that the association between black smoke and birth weight may be mediated through intrauterine growth restriction. The associations between black smoke and birth weight were of the same order of magnitude as those reported for passive smoking. These findings add to the growing evidence of the harmful effects of air pollution on birth outcomes.</p

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity &gt; 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI