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Although both C-C chemokine receptor 5 (CCR5)- and CXC chemokine receptor 4 (CXCR4)-using HIV-1 strains cause AIDS, the emergence of CXCR4-utilizing variants is associated with an accelerated decline in CD4 + T cells. It remains uncertain if CXCR4-using viruses hasten disease or if these variants only emerge after profound immunological damage. We show that exclusively CXCR4- as compared to cocirculating CCR5-utilizing variants are less sensitive to neutralization by both contemporaneous autologous plasma and plasma pools from individuals that harbor only CCR5-using HIV-1. The CXCR4-utilizing variants, however, do not have a global antigenic change because they remain equivalently susceptible to antibodies that do not target coreceptor binding domains. Studies with envelope V3 loop directed antibodies and chimeric envelopes suggest that the neutralization susceptibility differences are potentially influenced by the V3 loop. In vitro passage of a neutralization sensitive CCR5-using virus in the presence of autologous plasma and activated CD4 + T cells led to the emergence of a CXCR4-utilizing virus in 1 of 3 cases. These results suggest that in some but not necessarily all HIV-1 infected individuals humoral immune pressure against the autologous virus selects for CXCR4-using variants, which potentially accelerates disease progression. Our observations have implications for using antibodies for HIV-1 immune therapy.

The Reloncaví estuary in southern Chile is famous for its aquaculture. However, recurring harmful algal blooms have adversely affected mussel production. Therefore, regular monitoring of algal toxins is urgently needed to better understand the contamination status of the estuary. In this study, we quantified 15 types of lipophilic shellfish toxins in Metri Bay in the Reloncaví estuary on a biweekly basis for 4 years. We identified algal species using microscopy and metabarcoding analysis. We also measured water temperature, salinity, chlorophyll-a, and dissolved oxygen to determine the potential relationships of these parameters with algal toxin production. Our results revealed the presence of a trace amount of pectenotoxin and the causal phytoplankton Dinophysis, as well as yessotoxin and the causal phytoplankton Protoceratium. Statistical analysis indicated that fluctuations in water temperature affected the detection of these toxins. Additionally, metabarcoding analysis detected the highly toxic phytoplankton Alexandrium spp. in some samples. Although our results suggest that the level of lipophilic shellfish toxins in Metri Bay during the study period was insignificantly low using our current LC-MS method, the confirmed presence of highly toxic algae in Metri Bay raises concerns, given that favorable environmental conditions could cause blooms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The study of marine toxins in shellfish is of the utmost importance to ensure people's food safety. Marine toxins in shellfish and microalgae in the water column off the south-central coast of Chile (36°‒43° S) were studied in a network of 64 stations over a 14-month period. The relative abundance of harmful species Alexandrium catenella, Alexandrium ostenfeldii, Protoceratium reticulatum, Dinophysis acuminata, Dinophysis acuta, Pseudo-nitzschia seriata group and P. delicatissima group was analyzed. The detection and quantification of lipophilic toxins and domoic acid (DA) in shellfish was determined by UHPLC-MS/MS, and for Paralytic Shellfish Toxins (PSTs) by HPLC-FD with post-column oxidation, while for a culture of A. ostenfeldii a Hylic-UHPLC-MS/MS was used. Results showed that DA, gonyautoxin (GTX)-2, GTX-3 and pectenotoxin (PTX)-2 were detected below the permitted limits, while Gymnodimine (GYM)-A and 13-desmethylespirolide C (SPX-1) were below the limit of quantitation. According to the distribution and abundance record of microalgae, DA would be associated to P. seriata and P. delicatissima-groups, PTX-2 to D. acuminata, and GTX-2, GTX-3, GYM-A, and SPX-1 to A. ostenfeldii. However, the toxin analysis of an A. ostenfeldii culture from the Biobío region only showed the presence of the paralytic toxins C2, GTX-2, GTX-3, GTX-5 and saxitoxin, therefore, the source of production of GYM and SPX is still undetermined., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Dinophysis acuminata and D. acuta, which produce diarrheogenic toxins and pectenotoxins in southern Chile, display site-specific differences in interannual variability (2006 - 2018) in Reloncaví, Pitipalena and Puyuhuapi fjords (41 - 46 °S), Chilean Patagonia. Linear Models show decreasing trends in rainfall and river discharge. Latitudinal decreasing gradients in SST temperature and vertical salinity gradients were observed. A brackish water layer (FW salinity <11 psu), permanently present in Reloncaví, decreased in thickness with time in Pitipalena and was usually absent in Puyuhuapi, the only fjord where D. acuta reached bloom (>10 3 cells L ‒1 ) densities every season. Dinophysis acuminata, associated with toxin profiles in shellfish that include only pectenotoxins, bloomed everywhere with a poleward increasing gradient. Absence of the FW layer provides a possible index of risk for D. acuta blooms. An apparent poleward shift of D. acuta populations, responsible for DSP outbreaks in Reloncaví in the 1970s, and the recent EU deregulation of pectenotoxins will have a positive impact on the mussel industry in Los Lagos Region. Changes to ongoing monitoring protocols to improve risk assessment capabilities are suggested., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In Chile, the toxic dinoflagellate A. catenella shows an apparent oceanic range expansion from south to the north since its first detection in 1972 in the Magallanes Region (56° S). Until 2017, A. catenella detections were restricted to a geographic area between Magallanes to Los Rios Regions (40° S). The establishment of a monitoring program in the offshore Pacific coast allowed the detection of A. catenella between 2018 and 2019 in northern areas off the Bío-Bío Region (36°S). Monoclonal cultures established from the Bío-Bío coast were genetically identified, and PSTs screened. Phylogenetic analyses determined that the Bío-Bío isolates aggregated in Group I ribotype (previously A. tamarense or A. fundyense) and the presence of PSTs analogs were confirmed. It is the northernmost detection of the toxic dinoflagellate A. catenella in the Pacific coast of Chile. These results have important implications for species monitoring and governmental management in the Bío-Bío Region., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Trypanosoma cruzi uses various mechanisms of infection to access humans. Since 1967, food contaminated with metacyclic trypomastigotes has triggered several outbreaks of acute infection of Chagas disease by oral transmission. Follow-up studies to assess the effectiveness of anti-parasitic treatment of oral outbreaks are rather scarce. Here, we report a 10-year laboratory follow-up using parasitological, serological, and molecular tests of 106 individuals infected in 2007 of the largest known outbreak of orally transmitted Chagas disease, which occurred in Caracas city, Venezuela. Before treatment (2007), specific IgA, IgM and IgG, were found in 71% (75/106), 90% (95/106) and 100% (106/106), respectively, in addition to 21% (9/43) parasitemia, Complement Mediated Lysis (CML) in 98% (104/106) and 79% (34/43) parasitic DNA for PCR. Blood culture detected parasitemia up to 18 months post-treatment in 6% (6/106) of the patients. In 2017, the original number of cases in the follow-up decreased by 46% and due to the country's economic situation, not all the trials could be carried out in the entire population. During follow-up, IgA and IgM disappeared promptly, with IgM persisting in 19% (20/104) of the patients three years after treatment. The anti-T. cruzi IgG remained positive 10 years later in 41% (20/49) of the individuals evaluated. CML remained positive seven years later in 79% (65/82) of the cases. PCR positive cases decreased after treatment but progressively recovered, being positive in 69% (32/46) of the individuals evaluated in 2017. The group of children (under 18 years of age) showed the highest PCR positivity with 76% (26/34) of the cases, but their parasitic load tended to diminish, while in adults the parasitic load regained their initial values. The simultaneous evaluation of serological tests and PCR of the patients allowed us to separate patients among responders and non-responders to the anti-parasitic treatment, and this information prompted us to apply a second anti-parasitic treatment in the group of non-responders. In this population not subjected to the like lihood of re-infection, adult patients were more likely to be non-responders when compared to children. These results suggest that rigorous laboratory follow-up with T. cruzi infectious biomarkers is essential to detect cases of parasite persistence., (Copyright © 2021. Published by Elsevier B.V.)

American trypanosomiasis is one of the few native parasites of this continent. As a zoonosis, Trypanosoma cruzi infects about 180 species out of 25 families of mammals. Its regular transmission is through triatomines, which can easily transmit parasites either by the skin route (contamination of mammals skin with their feces) or by oral route (ingestion of food contaminated with complete triatomines or their feces) and additionally through haematogenous via (congenital and transfusional) and by tissues (transplants). The oral route, which seems to be the ancestral form of transmission to wild and domestic mammals, has recently become more important after the success achieved in the control of domicile vectors using residual pesticides. From its initial diagnosis in 1967, tens of oral outbreaks have been diagnosed mostly in the Brazilian Amazon and subsequently in other four countries in South America. Environmental imbalance caused by man through the invasion and deforestation of woodlands, results in reduction of biodiversity of mammals as food source for triatomines, affecting the "dilution effect" of T. cruzi in the nature increasing the risk of human infection. On the other hand, triatomines invade houses looking for new blood sources. One of the consequences of domiciliated triatomines is the food contamination spread, especially in home-made juices, which has been the source of infection of most oral outbreaks. Other biotic and abiotic factors help to explain the recent increase of oral transmission outbreaks of Chagas disease, distributed in nine eco-regions of America., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background & Aims: We have investigated the differences in plasma parameters and serum trace elements between "healthy" and unhealthy morbidly obese patients before and after Roux-en-Y gastric bypass surgery., Methods: A group of 32 morbidly obese patients undergoing bariatric surgery were divided into three groups. Group 1 subjects were free of dyslipidemia and type II diabetes mellitus (defined as "healthy" obese, DM-DL-); Group 2 subjects had only the presence of dyslipidemia (DM-DL+), while group 3 patients demonstrated the presence of both (DM + DL+). In all patients, we studied haematological, haemostasis, anaemia, coagulation plasma and trace elements parameters before and 1, 6 and 12 months after gastric bypass surgery., Results: We found significant differences in some haematological parameters, including haemostasis (e.g., T-Quick, p = 0.0048) and coagulation (e.g., ATIII and PAI-1, p = 0.001 and p < 0.0001, respectively) and in anaemia parameters (e.g., folate, cobalamin and transferrin, p = 0.0002, p < 0.0001 and p = 0.0001, respectively) but also in serum trace elements between the groups. However, the response to bariatric surgery was similar in the three groups., Conclusion: Any healthy morbid obese subject is really metabolically "unhealthy" because he or she has many other haematologic or serum abnormalities that are often not included in the criteria for the definition of "healthy" in these obese subjects., (Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background: The mechanisms responsible for the development of acute pancreatitis (AP) and its complications are not fully understood., Aim: To assess the role of clinical and host molecular factors for the development and outcome of persistent systemic inflammatory response syndrome (SIRS) in patients with AP., Methods: We included 191 patients with AP in the study. The considered variables were demographic characteristics, prognosis and outcome, etiology, laboratory findings and complications. Interleukin (IL) 10 (-1082 G/A, -592 C/A), TNFA-308 (G/A) and ILB-31 (C/T) polymorphisms were determined by pyrosequencing. An amplification refractory mutation system-polymerase chain reaction method was used to genotype the IL8-251 (A/T) polymorphism., Results: Demographic characteristics were not statistically significant risk factors for the acquisition of persistent SIRS in patients with AP. Patients with hypertriglyceridemia were more likely to develop persistent SIRS (P < 0.05). No association with the TNFA, ILB, IL8-251 (A/T) and IL10 single-nucleotide polymorphisms was detected from the allele, genotype or haplotype frequencies., Conclusions: Patients with hypertriglyceridemia-induced AP were more likely to develop persistent SIRS.

Introduction: Transient apical breakdown (TAB) caused by orthodontic treatment is a reversible resorptive process in which the apex of a tooth shows some radiographic evidence of resorption and the crown may display some discoloration. It usually requires no treatment other than monitoring and elimination of the orthodontic forces applied to the tooth., Methods: This report describes the case of a 48-year-old man patient who was referred to the department of endodontics for evaluation of some discoloration of his upper right central incisor, which was undergoing orthodontic treatment. The tooth was nonresponsive to sensitivity tests, it was sensitive to percussion, and, radiographically, there was some evidence of root resorption and apical radiolucency., Results: Because TAB was the suspected cause of the signs and symptoms, no treatment was performed on the tooth except for periodic recalls, and lightening and eventual removal of the orthodontic appliances was indicated., Conclusions: Ten weeks after the initial appointment and removal of the applied orthodontic forces, color improvement was observed, accompanied by a return of tooth sensitivity to cold tests., (Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The objective of this work was to study the abatement of 200mgL(-1) sulfamethoxazole (SMX) solution by means of photo-Fenton process. Biodegradability of the treated solutions was followed by the ratio biochemical oxygen demand at five days/chemical oxygen demand (BOD(5)/COD) and toxicity by Microtox and inhibition tests. Experiments with different initial concentration of H(2)O(2) were carried out. The initial amount of Fe(2+) and pH of the solution were set at 10mgL(-1) and 2.8 respectively. The temperature of the reactor was kept constant in all the experiments (25+/-0.8 degrees C). Photo-Fenton process is thought to be a successful treatment step to improve the biodegradability of wastewater containing SMX. The complete antibiotic removal was achieved for a H(2)O(2) dose over 300mgL(-1). Biodegradability (BOD(5)/COD) rose from zero (SMX solution) to values higher than 0.3 (treated solutions). Toxicity and inhibition tests pointed out in the same direction: oxidized intermediates for initial H(2)O(2) dose over 300mgL(-1) showed no toxicity effects on pure bacteria and no inhibition on activated sludge activity.