Spatio-temporal trends of mercury levels in alluvial gold mining spoils areas monitored between rainy and dry seasons in the Peruvian Amazon.

Artisanal and small-scale gold mining (ASGM) in the Amazon has degraded tropical forests and escalated mercury (Hg) pollution, affecting biodiversity, ecological processes and rural livelihoods. In the Peruvian Amazon, ASGM annually releases some 181 tons of Hg into the environment. Despite some recent advances in understanding the spatial distribution of Hg within gold mine spoils and the surrounding landscape, temporal dynamics in Hg movement are not well understood. We aimed to reveal spatio-temporal trends of soil Hg in areas degraded by ASGM.,. We analyzed soil and sediment samples during the dry and rainy seasons across 14 ha of potentially contaminated sites and natural forests, in the vicinities of the Native community of San Jacinto in Madre de Dios, Peru. Soil Hg levels of areas impacted by ASGM (0.02 ± 0.02 mg kg-1) were generally below soil environmental quality standards (6.60 mg kg-1). However, they showed high variability, mainly explained by the type of natural cover vegetation, soil organic matter (SOM), clay and sand particles. Temporal trends in Hg levels in soils between seasons differed between landscape units distinguished in the mine spoils. During the rainy season, Hg levels decreased up to 45.5% in uncovered soils, while in artificial pond sediments Hg increased by up to 961%. During the dry season, uncovered degraded soils were more prone to lose Hg than sites covered by vegetation, mainly due to higher soil temperatures and concomitantly increasing volatilization. Soils from natural forests and degraded soil covered by regenerating vegetation showed a high capacity to retain Hg mainly due to the higher plant biomass, higher SOM, and increasing concentrations of clay particles. Disturbingly, our findings suggest high Hg mobility from gold mine spoil to close by sedimentary materials, mainly in artificial ponds through alluvial deposition and pluvial lixiviation. Thus, further research is needed on monitoring, and remediation of sediments in artificial to design sustainable land use strategies.

Mercury bioaccumulation in bats in Madre de Dios, Peru: implications for Hg bioindicators for tropical ecosystems impacted by artisanal and small-scale gold mining.

Mercury (Hg) endangers human and wildlife health globally, primarily due to its release from artisanal small-scale gold mining (ASGM). During gold extraction, Hg is emitted into the environment and converted to highly toxic methylmercury by microorganisms. In Madre de Dios (MDD), Peru, ASGM dominates the economy and has transformed rainforests into expansive deforested areas punctuated by abandoned mining ponds. The aim of this study was to evaluate the use of bats as bioindicators for mercury pollution intensity in tropical terrestrial ecosystems impacted by ASGM. We collected 290 bat fur samples from three post-ASGM sites and one control site in Madre de Dios. Our results showed a wide Hg distribution in bats (0.001 to 117.71 mg/kg) strongly influenced by feeding habits. Insectivorous and piscivorous bats from ASGM sites presented elevated levels of Hg surpassing the mercury small mammal threshold for small mammals (10 mg/kg). We observed the highest reported fur mercury concentrations for insectivorous Neotropical bats reported to date (Rhynchonycteris naso, 117 mg/kg). Our findings further confirm that Hg emissions from ASGM are entering local food webs and exposing wildlife species at several trophic levels to higher levels of Hg than in areas not impacted by mining. We also found that three bat genera consistently showed increased Hg levels in ASGM sites relative to controls indicating potential usefulness as bioindicators of mercury loading in terrestrial ecosystems impacted by artisanal and small-scale gold mining.

The NHE3 Inhibitor Tenapanor Prevents Intestinal Obstructions in CFTR-Deleted Mice.

Mutations in the CFTR chloride channel result in intestinal obstructive episodes in cystic fibrosis (CF) patients and in CF animal models. In this study, we explored the possibility of reducing the frequency of obstructive episodes in cftr-/- mice through the oral application of a gut-selective NHE3 inhibitor tenapanor and searched for the underlying mechanisms involved. Sex- and age-matched cftr+/+ and cftr-/- mice were orally gavaged twice daily with 30 mg kg-1 tenapanor or vehicle for a period of 21 days. Body weight and stool water content was assessed daily and gastrointestinal transit time (GTT) once weekly. The mice were sacrificed when an intestinal obstruction was suspected or after 21 days, and stool and tissues were collected for further analysis. Twenty-one day tenapanor application resulted in a significant increase in stool water content and stool alkalinity and a significant decrease in GTT in cftr+/+ and cftr-/- mice. Tenapanor significantly reduced obstructive episodes to 8% compared to 46% in vehicle-treated cftr-/- mice and prevented mucosal inflammation. A decrease in cryptal hyperproliferation, mucus accumulation, and mucosal mast cell number was also observed in tenapanor- compared to vehicle-treated, unobstructed cftr-/- mice. Overall, oral tenapanor application prevented obstructive episodes in CFTR-deficient mice and was safe in cftr+/+ and cftr-/- mice. These results suggest that tenapanor may be a safe and affordable adjunctive therapy in cystic fibrosis patients to alleviate constipation and prevent recurrent DIOS.

Assessment of plasma catecholamines in patients with dysmetabolic iron overload syndrome.

BACKGROUND: Dysmetabolic iron overload syndrome (DIOS) is characterized by hyperferritinemia and normal transferrin saturation level with components of metabolic syndrome (MS). Among cases of MS, we determined those with DIOS and their characterizations, then we evaluated the association between plasma catecholamines status and hypertension in DIOS. METHODS: We compared 101 hypertensive patients with 50 healthy participants (control group). Iron (iron, transferrin, and ferritin), insulin, and plasma catecholamine (adrenaline, noradrenaline, and dopamine), profiles were measured for both groups. Homeostasis model assessment of insulin resistance index and transferrin saturation were also calculated. RESULTS: Out of 101 hypertensive patients, 64 were diagnosed with MS, and 6 of the latter met the DIOS diagnostic criteria. Significantly, DIOS patients were older and had lower body mass index (BMI) compared with hypertensive non-DIOS patients with p-values of (0.026), and (0.033), respectively. Adrenaline, noradrenaline, and dopamine levels did not differ significantly between DIOS and non-DIOS patients. CONCLUSIONS: Of the MS patients, 9.3% were diagnosed with DIOS. Accordingly, complete iron profiling should be performed routinely in the cases of MS for early diagnosis of DIOS, to prevent future complications. Further studies are required to test the hypothesis linking older age and lower BMI with the pathogenesis of DIOS.

Mercury bioaccumulation in tropical bats from a region of active artisanal and small-scale gold mining.

Mercury negatively affects human and animal health. Artisanal and small-scale gold mining can be a major local source of mercury contamination, especially into aquatic systems in tropical areas. Animals associated with mercury-contaminated aquatic systems are at high risk of experiencing effects of this heavy metal, but it is not clear how far the effects may extend into nearby terrestrial systems. We report mercury contamination levels in bats in agricultural areas at increasing distances from gold mining (~3-89 km of distance). We hypothesized that bat mercury concentrations would differ between feeding guilds, land use types, and be higher at sites closer to gold mining areas. We collected 112 fur samples from 30 bat species and eight guilds, and provide the first reports of concentrations in 12 species. All mercury concentrations were below the level at which health is likely to be affected (10 ppm). We found guild-influenced differences among mercury concentration levels, with the highest concentrations in aerial insectivores and carnivores, and the lowest in canopy frugivores. Our results suggest insectivorous and carnivorous bats may still be at some risk even at sites distant from aquatic mercury contamination. We did not find an effect of agricultural land-use type on mercury concentrations within species or guilds, suggesting mercury contamination did not extend to agricultural sites from areas of gold mining activities, and that these agricultural activities themselves were not an important source of mercury. We conclude bats did not demonstrate a signature of mercury risk either as a result of proximity of gold mining, or as a result of agricultural activities.

Top-down, Bottom-up and Sideways: The Multilayered Complexities of Multi-level Actors Shaping Forest Governance and REDD+ Arrangements in Madre de Dios, Peru.

This study examines the role multilevel governance plays in the adoption of sustainable landscape management initiatives in emerging arrangements aimed at reducing emissions from deforestation and forest degradation (REDD+). It sheds light on the challenges these multiple layers of actors and interests encounter around such alternatives in a subnational jurisdiction. Through transcript analysis of 93 interviews with institutional actors in the region of Madre de Dios, Peru, particularly with regard to five sites of land-use change, we identified the multiple actors who are included and excluded in the decision-making process and uncovered their complex interactions in forest and landscape governance and REDD+ arrangements. Madre de Dios is a useful case for studying complex land-use dynamics, as it is home to multiple natural resources, a large mix of actors and interests, and a regional government that has recently experienced the reverberations of decentralization. Findings indicate that multiple actors shaped REDD+ to some extent, but REDD+ and its advocates were unable to shape land-use dynamics or landscape governance, at least in the short term. In the absence of strong and effective regional regulation for sustainable land use alternatives and the high value of gold on the international market, illegal gold mining proved to be a more profitable land-use choice. Although REDD+ created a new space for multilevel actor interaction and communication and new alliances to emerge, the study questions the prevailing REDD+ discourse suggesting that better coordination and cooperation will lead to integrated landscape solutions. For REDD+ to be able to play a role in integrated landscape governance, greater attention needs to be paid to grassroots actors, power and authority over territory and underlying interests and incentives for land-use change.

Unlicensed to Prescribe Herbs: A Chinese Healer - Médico Chino - in Puerto Rico, 1851-1853.

In Puerto Rico and Cuba, the phrase "can't be saved even by the Chinese physician" ("no lo salva ni el médico chino") indicates a person with an incurable disease. The documents at the Archivo General de Puerto Rico include three requests for a medical license from a Chinese immigrant, Juan de Dios Sian (Lin Hua Cheng). Despite lacking legal credentials, he used herbal therapies to treat chronically ill persons in Ponce, San Juan and Mayaguez from 1851 to 1853. Before arriving in Ponce he had spent four years in Cuba, where he is again found by 1865. Sian's petitions show that Puerto Rico, like Cuba, experienced a widely known "médico chino." The anecdote reminds us of important issues in our medical and social history: Asiatic immigration (earlier, larger and more diverse than usually considered), access to care (and its limitations), and the long history of herbal medicine in Oriental and Western cultures. Elements of this story, such as the eagerness for new treatments among patients who have derived no benefit from standard therapy, the ethics of medical licensing, the impotence of licensing agencies and the toleration of authorities regarding an unorthodox but popular healer, exemplify dilemmas that accompany medical practice at all times.

Constipation and DIOS: Diagnosis, differential diagnosis, and management.

Cystic Fibrosis (CF) is a complex disorder that requires multidisciplinary expertise for effective management. The GALAXY study estimated the prevalence of constipation to be about 25% among People with Cystic Fibrosis (PwCF), identifying it as one of the common gastrointestinal (GI) symptoms within this patient population. Quality of Life (QoL) assessments uncovered high patient dissatisfaction, highlighting the imperative need for enhanced treatment strategies. Similarly, Distal Intestinal Obstruction Syndrome (DIOS) is a unique condition exclusive to PwCF that, if left undiagnosed, can lead to considerable morbidity and mortality. Given the broad spectrum of differential diagnoses for abdominal pain, including constipation and DIOS, it is paramount for healthcare providers to possess a clear understanding of these conditions. This paper aims to delineate various differentials for abdominal pain while elucidating the pathogenesis, diagnostic criteria, and treatment options for managing constipation and DIOS in PwCF.

Changes in floristic and vegetation structure in a chronosequence of abandoned gold-mining lands in a tropical Amazon forest.

This study analyzes floristic and vegetation structure changes during forest succession after disturbances caused by small-scale gold mining in Madre de Dios (Peru). We compared the floristic and vegetation structure of a reference forest against three sites with different periods of abandonment after mining (5, 11 and 23-years). Three 20 × 60 m plots were defined on each site, and all tree species with a DBH >1 cm within the plots were inventoried. To evaluate species diversity and similarity, the Importance Value, effective numbers of species (0D, 1D, and 2D), and Chao-Jaccard similarity index were calculated. We used the Nonmetric multidimensional scaling for similarity ordination and the PERMANOVA test to evaluate differences in floristic composition. We recorded 129 tree species in the study areas and statistically significant differences between initial and intermediate stages were observed regarding floristic composition, basal area, height, and DBH. The transition from the initial successional stage to the reference forest produces an increase in basal area, species diversity, and floristic similarity. The 23-year-old stand had more species in common with the 11-year-old stand than the reference forest. Our results showed a high proportion of pioneer species and anemochory dispersal syndrome in the initial successional stages, but they decreased in later stages of the chronosequence. The floristic and structural attributes of forests throughout the chronosequence showed a fast recovery during secondary succession. After 23 years, the recovery of tree species density was 77 % of reference forest, while the relative recovery of species composition was much slower, on average 23 %. These results provide essential information to guide the selection of suitable species in ecological restoration projects after abandonment. Implementing forest restoration strategies based on reliable information to accelerate the process of vegetation succession is critical for recuperating areas degraded by gold mining at the Peruvian Amazon.

Diosmetin ameliorates psoriasis-associated inflammation and keratinocyte hyperproliferation by modulation of PGC-1α / YAP signaling pathway.

Psoriasis, characterized by aberrant epidermal keratinocyte proliferation and differentiation, is a chronic inflammatory immune-related skin disease. Diosmetin (Dios), derived from citrus fruits, exhibits anti-inflammatory and anti-proliferative properties. In this study, IL-17A-induced HaCaT cell model and Imiquimod (IMQ)-induced mouse model were utilized to investigate the effects of Dios against psoriasis. The morphology and biomarkers of psoriasis were regarded as the preliminary evaluation including PASI score, skin thickness, H&E staining, EdU staining and inflammatory factors. Transcriptomics analysis revealed PGC-1α as a key target for Dios in ameliorating psoriasis. Specifically, Dios, through PGC-1α, suppressed YAP-mediated proliferation and inflammatory responses in psoriatic keratinocytes. In conclusion, Dios shows promise in psoriasis treatment and holds potential for development as targeted medications for application in psoriasis.