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1.
J Environ Sci (China) ; 148: 230-242, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095160

RESUMEN

Fish constitutes the main protein source for the Amazonian population. However, the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored. Here we assessed exposure levels of 10 trace elements and metals (Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Pb, and Hg) in 56 samples belonging to 11 different species of fish from the Brazilian Amazon. We studied the relationship between exposure levels, fish origin, and fish feeding habits, and assessed toxicological and carcinogenic risks for the Amazonian population. No significant correlation was found between sampling site and exposure levels to the studied elements, but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain. The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption. This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg, As and Cr that exceed the oral reference dose, thus posing a toxicological concern. Furthermore, carcinogenic risks may be expected due to the continued exposure to Cr and As. The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled. Moreover, continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended, particularly for riverine and indigenous communities.


Asunto(s)
Peces , Contaminación de Alimentos , Metales , Oligoelementos , Contaminantes Químicos del Agua , Animales , Brasil , Humanos , Contaminantes Químicos del Agua/análisis , Oligoelementos/análisis , Contaminación de Alimentos/análisis , Medición de Riesgo , Metales/análisis , Monitoreo del Ambiente
2.
Parasitol Int ; 103: 102943, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39098654

RESUMEN

From genus Myxobolus, cnidarians of Myxozoa class, is well known for infecting economically important fish species and, as result, relevant losses in aquaculture production can be observed. They are present in a big range of fish in its natural habitat, including the migratory Brachyplatystoma rousseauxii catfish. This study aimed is to develop an integrative characterization of a new species of Myxobolus, located in B. rousseauxii's gills. To accomplish this, 30 specimens of B. rousseauxii catfish were collected from Mosqueiro Island in Pará, Brazil; necropsied and analyzed for morphology, histology and molecular characteristics. Cysts with conjunctival capsule development made up of fibroblasts were observed at the gill arches; such proliferation caused bone tissue loss and cartilage compression. The cysts contained Myxobolus myxospores measuring 9.9 µm of length and 9.6 µm of width, whereas polar capsules were 5.4 µm long and 3.4 µm wide, with 8 to 9 coils of polar tubules. Phylogenetic analyses revealed that new species were included in a subclade alongside species from the same geographic location and infection site that infect Siluriformes fish. Morphological and molecular differences revealed that Myxobolus spp. parasite-host associations through histopathology supporting the designation of a new M. rousseauxii n. sp. species in B. rousseauxii, a commercially important fish.

3.
Interact J Med Res ; 13: e58635, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133905

RESUMEN

BACKGROUND: Previous research and safety advocacy groups have proposed various behaviors for older adults to actively engage in medication safety. However, little is known about how older adults perceive the importance and reasonableness of these behaviors in ambulatory settings. OBJECTIVE: This study aimed to assess older adults' perceptions of the importance and reasonableness of 8 medication safety behaviors in ambulatory settings and compare their responses with those of younger adults. METHODS: We conducted a survey of 1222 adults in the United States using crowdsourcing to evaluate patient behaviors that may enhance medication safety in community settings. A total of 8 safety behaviors were identified based on the literature, such as bringing medications to office visits, confirming medications at home, managing medication refills, using patient portals, organizing medications, checking medications, getting help, and knowing medications. Respondents were asked about their perception of the importance and reasonableness of these behaviors on a 5-point Likert rating scale in the context of collaboration with primary care providers. We assessed the relative ranking of behaviors in terms of importance and reasonableness and examined the association between these dimensions across age groups using statistical tests. RESULTS: Of 1222 adult participants, 125 (10.2%) were aged 65 years or older. Most participants were White, college-educated, and had chronic conditions. Older adults rated all 8 behaviors significantly higher in both importance and reasonableness than did younger adults (P<.001 for combined behaviors). Confirming medications ranked highest in importance (mean score=3.78) for both age groups while knowing medications ranked highest in reasonableness (mean score=3.68). Using patient portals was ranked lowest in importance (mean score=3.53) and reasonableness (mean score=3.49). There was a significant correlation between the perceived importance and reasonableness of the identified behaviors, with coefficients ranging from 0.436 to 0.543 (all P<.001). CONCLUSIONS: Older adults perceived the identified safety behaviors as more important and reasonable than younger adults. However, both age groups considered a behavior highly recommended by professionals as the least important and reasonable. Patient engagement strategies, common and specific to age groups, should be considered to improve medication safety in ambulatory settings.

4.
Proc Biol Sci ; 291(2029): 20240659, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39163980

RESUMEN

Species worldwide are experiencing anthropogenic environmental change, and the long-term impacts on animal cultural traditions such as vocal dialects are often unknown. Our prior studies of the yellow-naped amazon (Amazona auropalliata) revealed stable vocal dialects over an 11-year period (1994-2005), with modest shifts in geographic boundaries and acoustic structure of contact calls. Here, we examined whether yellow-naped amazons maintained stable dialects over the subsequent 11-year time span from 2005 to 2016, culminating in 22 years of study. Over this same period, this species suffered a dramatic decrease in population size that prompted two successive uplists in IUCN status, from vulnerable to critically endangered. In this most recent 11-year time span, we found evidence of geographic shifts in call types, manifesting in more bilingual sites and introgression across the formerly distinct North-South acoustic boundary. We also found greater evidence of acoustic drift, in the form of new emerging call types and greater acoustic variation overall. These results suggest cultural traditions such as dialects may change in response to demographic and environmental conditions, with broad implications for threatened species.


Asunto(s)
Amazona , Vocalización Animal , Animales , Amazona/fisiología , Especies en Peligro de Extinción , Densidad de Población , Conservación de los Recursos Naturales
5.
IJID Reg ; 12: 100388, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39104380

RESUMEN

Objectives: To examine the epidemiology of hospitalized cases of malaria in indigenous people living in the municipalities of Roraima in the northern Brazilian Amazon from 2008 to 2022. Methods: Ecological study using secondary data and spatiotemporal analyses based on thematic maps. Average rates were calculated per study period and spatiotemporal clusters were estimated from spatial statistics. Results: Of the 541 medical records, 77.08% were related to Plasmodium vivax. Higher rates were observed in municipalities in the south and center of the state. The rates increased throughout the study period. The analysis generated three clusters. Conclusions: Although Roraima has characteristics that worsen the malaria problem, no studies were found that examined the transmission of the disease in the state as a whole. This increases the importance of this study, which contributes to the discussion in the field of indigenous health.

6.
Inflammopharmacology ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126568

RESUMEN

Fridericia chica is an Amazonian plant used to treat stomach disorders. However, the pharmacological activity of flavonoids in the extract has yet to be investigated. Therefore, we considered that a flavonoid-rich F. chica subfraction (FRS) has gastroprotective functions. For this, before the induction of gastric ulcers with ethanol or piroxicam, the rats received vehicle (water), omeprazole (30 mg/kg), or FRS (30 mg/kg), and the ulcer area was measured macro and microscopically, and the antisecretory action was investigated in pylorus-ligated rats. In addition, the roles of nitric oxide (NO) and nonprotein sulfhydryl compounds (NP-SH) in the gastroprotective effects of FRS were studied. FRS reduced ethanol- and piroxicam-induced ulcerations by 81% and 77%, respectively, as confirmed histologically. Antioxidant effects were observed for FRS through the maintenance of GSH and LPO levels, and the SOD and CAT activity similar to those found in the nonulcerated group. Moreover, FRS avoided the increase in MPO activity and TNF, IL-6, IL-4 and IL-10 levels. Moreover, mucin staining increased in ulcerated rats receiving FRS, and the pharmacological mechanism gastroprotective seems to involve the NO and NP-SH in addition to antisecretory actions. The chemical study by mass spectrometry confirmed the presence of flavonoids in FRS, and molecular docking studies have shown that these compounds interact with cyclooxygenase-1 and NO synthase. Furthermore, there was no indication that FRS had cytotoxic effects. Our results support the popular use of F. chica, and we conclude that the gastroprotection effect promoted by FRS can be attributed to the combined effect of the flavonoids.

7.
Heliyon ; 10(14): e34157, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39108928

RESUMEN

The diversity of sustainable certifications raises questions about the credibility, intentions, and impacts of Voluntary Sustainability Standards (VSS) on Global Value Chains (GVC). Few studies show the impacts of VSS on different sustainable dimensions in sectors such as the non-timber forest product (NTFP) sector. This paper aims to investigate in the value chain of the most important NTFP in the Amazon, açaí, whether VSS contributes to sustainable outcomes in the Governance, Environmental, Economic, and Social dimensions. Using case studies in enterprises of the açaí chain and the use of tools and indicators was possible to generate information that is currently scarce for NTFPs in the Amazon from the VSS perspective. The results show that there is a great distance that the weakest links of the GVC (Micro, Small, and Medium Enterprises - MSMEs) must walk to adopt VSS and be inserted into the global market. The requirements are based on bureaucratic management activities, which are extraordinarily complex and involve many issues and indicators. The VSS lacks supplements that evaluate and validate the results reported by the companies as sustainable. Finally, the VSS is still far from ensuring an inclusive and fully sustainable chain by itself.

8.
Emerg Infect Dis ; 30(9): 1884-1894, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39174028

RESUMEN

Malaria is increasingly diagnosed in urban centers across the Amazon Basin. In this study, we combined repeated prevalence surveys over a 4-year period of a household-based random sample of 2,774 persons with parasite genotyping to investigate the epidemiology of malaria in Mâncio Lima, the main urban transmission hotspot in Amazonian Brazil. We found that most malarial infections were asymptomatic and undetected by point-of-care microscopy. Our findings indicate that as malaria transmission decreases, the detection threshold of microscopy rises, resulting in more missed infections despite similar parasite densities estimated by molecular methods. We identified genetically highly diverse populations of Plasmodium vivax and P. falciparum in the region; occasional shared lineages between urban and rural residents suggest cross-boundary propagation. The prevalence of low-density and asymptomatic infections poses a significant challenge for routine surveillance and the effectiveness of malaria control and elimination strategies in urbanized areas with readily accessible laboratory facilities.


Asunto(s)
Microscopía , Brasil/epidemiología , Humanos , Prevalencia , Microscopía/métodos , Femenino , Masculino , Adulto , Adolescente , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Niño , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Falciparum/prevención & control , Malaria/epidemiología , Malaria/transmisión , Malaria/prevención & control , Malaria/parasitología , Plasmodium vivax/genética , Población Urbana , Preescolar , Plasmodium falciparum/genética , Persona de Mediana Edad , Adulto Joven , Lactante , Historia del Siglo XXI
9.
Sci Total Environ ; 950: 175189, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39097021

RESUMEN

This research analyses 24 years of oil extraction in blocks 16 and 67 of the Yasuní National Park (YNP) in the Amazonian Forest of Ecuador, one of the most biodiverse spaces in the world and with the current presence of ancient indigenous communities. As a novel contribution, we have carried out a Life-Cycle Assessment (LCA) that quantifies the footprints associated with the extraction, transportation, refining, distribution and final uses of the oil in four different scenarios (oil for asphalt use, electricity, marine fuel and passenger car transport). This study also sheds light on the energy return at the point of use of different oil-derivatives, and complements this with a qualitative analysis of the social, cultural and environmental implications for the Waorani communities. We conclude that the environmental burdens of the extraction process in blocks 16 and 67 in 2015 were greater than those of countries such as the United States, Saudi Arabia and Indonesia, based on the analysis of 11 impact categories. The blocks' operation is the most unfavourable for the categories of Terrestrial Acidification Potential (TAP), Global Warming Potential (GWP), Terrestrial Ecotoxicity Potential (TEP) and Ecosystem Quality Loss Potential (EQL), with increments of 804.15 %, 105.36 %, 506.29 % and 210.73 %, respectively, in relation to the average of the rest of the extraction systems analysed. Specifically, the present case study shows 75.18 % higher impacts in the blocks addressed, when compared to the Ecuadorian average. During the period 1999-2022, the carbon emissions associated with the oil extraction in these blocks have increased by 139.01%. It has been detected a neo-colonial economic behaviour: while the Ecuadorian state received 21% of the sales, the Spanish government and the oil companies received, on average, 38% and 41% of the per-litre average fuel price, respectively. Thus, 79% of the income stayed in the Global North. We conclude that, on average, 19.64 % of the impacts associated with crude oil production and consumption occur in the Amazonian region of the YNP, depending on the fuel used and the consumption mechanism. For the Global Warming Potential (GWP) impact category, the extraction process carries, on average, 34.51 % of the weight in all of the life-cycle impacts, depending on the consumption scenario. It was also estimated that to be able to use 0.33 kWh of electricity from fuel combustion, 0.47 kWh of energy for goods transport and 0.20 kWh for passenger transport, an investment of 1 kWh is required, with an average extended EROI of 1:3.33. According to the qualitative analysis performed, it has been concluded that the main local impacts are related to the obstacles in environmental monitoring and information, the economic dependence of the communities on the oil extraction company, and cultural transformations; impacts that are not easily quantifiable or detectable using other methodologies. The combination of the qualitative analysis and LCA showed that the neo-colonial economic distribution did not compensate the social and environmental impacts of the oil extraction occurred in the YNP.

10.
Environ Pollut ; 360: 124656, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39116927

RESUMEN

The aim of this study was to investigate the presence of alien phytoplankton species transported through ballast water of ships that docked on the Amazon coast. Phytoplankton samples were collected from 25 ships between 2012 and 2014, revealing 215 identified species, mostly comprising oceanic planktonic marine species. However, several coastal and freshwater species not yet documented on the Maranhão coast were also observed. The identification of several coastal and freshwater species not yet recorded for Amazonian environments in the ballast water of the Ponta da Madeira Maritime Terminal (TMPM), as well as toxic microalgae genera such as the dinoflagellates Alexandrium and Gymnodinium and of some diatom species from the genus Pseudo-nitzchia, raises concerns regarding the possibility of introducing species. This indicates that ballast water can be responsible for the introduction of alien species in Amazonian aquatic environments, thereby highlighting the TMPM as a critical hotspot in the Amazonian region.

11.
Environ Res ; 261: 119767, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39128663

RESUMEN

Human biomonitoring of toxic and essential trace elements is critically important for public health protection. Amazonian riverine communities exhibit distinctive dietary patterns, heavily reliant on locally sourced fish, fruits, and vegetables. These habits may result in unique exposure profiles compared to urban populations. However, comprehensive assessments of their exposure to toxic and essential metals are lacking, representing a critical gap in understanding the health risks faced by these communities. This study aimed to establish baseline levels of 21 metals and metalloids in human blood and explore the influence of sociodemographic factors, dietary habits, and lifestyle choices as potential sources of exposure to these elements. A cross-sectional biomonitoring investigation was conducted with 1,024 individuals from 13 communities in the Tapajós and Amazon Basins (Pará, Brazil). Most of the elements in study was determined for the first time in the region. Blood samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The levels of all elements were summarized by quantiles and compared with cutoff values from other Brazilian populations. Multiple linear regression was used to assess possible associations between element concentrations and sociodemographic characteristics, dietary habits, and lifestyle choices. High detection rates (64%-100%) were observed, indicating the widespread presence of these elements. Elevated blood concentrations were found for mercury (median 21.1 µg.L-1, interquartile range: 12-34 µg.L-1), selenium (median 166 µg.L-1, interquartile range: 137-208 µg.L-1), and lead (median 34 µg.L-1, interquartile range: 20.8-64 µg.L-1). Regression analysis revealed a positive association between mercury levels and fish consumption, while manioc flour intake showed no relationship to lead levels. In conclusion, our findings emphasize the need for continued monitoring and public policy development for these vulnerable populations. Further studies should assess long-term trends and investigate the health implications of prolonged exposure to diverse chemicals in Amazonian riverside communities.

12.
Food Res Int ; 192: 114729, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147481

RESUMEN

The Amazon region is known for its continental dimension, water abundance, and especially for the rich biodiversity that this biome hosts. Among the thousands of plant species in the Amazon, many represent food sources. Among these, cupuaçu (Theobroma grandiflorum (Willd. ex Spreng.) K.Schum.) stands out as an iconic fruit with an exotic flavor, appreciated for its remarkable organoleptic properties. The present review aims to provide a comprehensive description of its biology, agronomical uses, nutritional values, chemical compositions, medicinal properties, and industrial applications. The search based on scientific articles demonstrates T. grandiflorum as a valuable ingredient for the food, cosmetic and pharmaceutical sectors. Data analysis demonstrates that cupuaçu cultivation and processing contribute to the strengthening of local production chains and promotes the development of small communities, and thus the bioeconomy in the Amazon region. In this sense, since the last decade, cultivar improvement has required multidisciplinary efforts, resulting in disease-resistant plants with better productivity. Regarding its chemical composition, T. grandiflorum is a notable source of methylxanthine alkaloids, polyphenols, aroma compounds, and lipids. The presence of these compounds supports the use of cupuaçu in various products and help us to understand the potential health benefits of its consumption. Through the integration of all collected information, key gaps in basic and applied sciences were observed, highlighting the need for more research to uncover novel applications and products of T. grandiflorum. The development of new products based on biodiversity is fundamental to promoting environmental and economic sustainability, which are key steps to the survival of the Amazon rainforest. Therefore, this work summarizes the knowledge on this source and sheds light on a food source that is little known outside of the Amazon borders.


Asunto(s)
Frutas , Valor Nutritivo , Frutas/química , Humanos
13.
Proc Natl Acad Sci U S A ; 121(33): e2310157121, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39102539

RESUMEN

The Amazon forest contains globally important carbon stocks, but in recent years, atmospheric measurements suggest that it has been releasing more carbon than it has absorbed because of deforestation and forest degradation. Accurately attributing the sources of carbon loss to forest degradation and natural disturbances remains a challenge because of the difficulty of classifying disturbances and simultaneously estimating carbon changes. We used a unique, randomized, repeated, very high-resolution airborne laser scanning survey to provide a direct, detailed, and high-resolution partitioning of aboveground carbon gains and losses in the Brazilian Arc of Deforestation. Our analysis revealed that disturbances directly attributed to human activity impacted 4.2% of the survey area while windthrows and other disturbances affected 2.7% and 14.7%, respectively. Extrapolating the lidar-based statistics to the study area (544,300 km2), we found that 24.1, 24.2, and 14.5 Tg C y-1 were lost through clearing, fires, and logging, respectively. The losses due to large windthrows (21.5 Tg C y-1) and other disturbances (50.3 Tg C y-1) were partially counterbalanced by forest growth (44.1 Tg C y-1). Our high-resolution estimates demonstrated a greater loss of carbon through forest degradation than through deforestation and a net loss of carbon of 90.5 ± 16.6 Tg C y-1 for the study region attributable to both anthropogenic and natural processes. This study highlights the role of forest degradation in the carbon balance for this critical region in the Earth system.


Asunto(s)
Carbono , Conservación de los Recursos Naturales , Bosques , Brasil/epidemiología , Carbono/metabolismo , Humanos , Árboles/crecimiento & desarrollo , Ciclo del Carbono
14.
Int J Parasitol Parasites Wildl ; 24: 100961, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39070049

RESUMEN

Nematodes collected from the stomach of the yellow-spotted turtle Podocnemis unifilis Troschel, 1848 (Testudinidae) in the Brazilian state of Pará are assigned to a new genus, allocated to the family Atractidae (Cosmocerdoidea). Acanthoatractis n. gen. differs from all other genera of Atractidae based on the combination of the following morphological characters: cephalic extremity surrounded by eight bifurcated, wrench-shaped sclerotized structures arranged in a circle; oral opening encircled by two sclerotized pieces with pointed ends and a median portion with a pair of hooks; in males the larger (left) spicule is narrower in the middle third and the gubernaculum is absent. The type species, Acanthoatractis xinguensis n. gen., n. sp., has nine pairs of caudal papillae and a single papilla anterior to the cloacal lip. The new species is the seventh record of an atractid genus parasitizing P. unifilis.

15.
J Appl Stat ; 51(10): 1878-1893, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071253

RESUMEN

As the online market grows rapidly, people are relying more on product review when they purchase the product. Hence, many companies and researchers are interested in analyzing product review which essentially a text data. In the current literature, it is common to use only text analysis tools to analyze text dataset. But in our work, we propose a method that utilizes both text analysis method such as topic modeling and statistical network model to build network among individuals and find interesting communities. We introduce a promising framework that incorporates topic modeling technique to define the edges among the individuals and form a network and uses stochastic blockmodels (SBM) to find the communities. The power of our proposed method is demonstrated in real-world application to Amazon product review dataset.

16.
J Med Syst ; 48(1): 70, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39073632

RESUMEN

This is the second in a series of studies assessing the usability and reliability of a novel voice-based delivery system of mental health screening assessments. The previous study demonstrated the reliability and patient preference of a voice-based format of the Patient Health Questionnaire 9 (PHQ 9) for measuring major depression compared to a traditional paper format. Through this study, we further examined the Amazon Alexa tool in the administration of the General Anxiety Disorder 7 (GAD 7). With a replicated methodology to the first study, 40 newly administered patients completed the GAD 7 in one format at their first session and the alternate format at their follow up. Results from the new in clinic population replicated the findings observed in the first PHQ 9 study: GAD 7 assessment scores for the Alexa and paper version showed a high degree of reliability (α = 0.77), patients showed higher overall positive attitudes for the voice-based GAD 7 format, and subscales for attractiveness, stimulation, and novelty were significantly higher for the voiced-based format. Results also demonstrated 42 (84%) of the 50 patients who completed the voice-based format responded as being willing to use the device from home. With new recommendations of universal screening of anxiety disorders for patients below the age of 65 and rapid changes in virtual mental healthcare, convenient screenings are more important than ever. We believe this novel clinical assessment tool has the potential to improve patient behavioral healthcare while mitigating the workload of healthcare professionals.


Asunto(s)
Trastornos de Ansiedad , Humanos , Femenino , Masculino , Reproducibilidad de los Resultados , Persona de Mediana Edad , Adulto , Trastornos de Ansiedad/diagnóstico , Voz , Encuestas y Cuestionarios , Psicometría , Anciano
17.
Sci Total Environ ; 947: 174378, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38960201

RESUMEN

Understanding the Amazon Rainforest's response to shifts in precipitation is paramount with regard to its sensitivity to climate change and deforestation. Studies using Dynamic Global Vegetation Models (DGVMs) typically only explore a range of socio-economically plausible pathways. In this study, we applied the state-of-the-art DGVM LPJmL to simulate the Amazon forest's response under idealized scenarios where precipitation is linearly decreased and subsequently increased between current levels and zero. Our results indicate a nonlinear but reversible relationship between vegetation Above Ground Biomass (AGB) and Mean Annual Precipitation (MAP), suggesting a threshold at a critical MAP value, below which vegetation biomass decline accelerates with decreasing MAP. We find that approaching this critical threshold is accompanied by critical slowing down, which can hence be expected to warn of accelerating biomass decline with decreasing rainfall. The critical precipitation threshold is lowest in the northwestern Amazon, whereas the eastern and southern regions may already be below their critical MAP thresholds. Overall, we identify the seasonality of precipitation and the potential evapotranspiration (PET) as the most important parameters determining the threshold value. While vegetation fires show little effect on the critical threshold and the biomass pattern in general, the ability of trees to adapt to water stress by investing in deep roots leads to increased biomass and a lower critical threshold in some areas in the eastern and southern Amazon where seasonality and PET are high. Our findings underscore the risk of Amazon forest degradation due to changes in the water cycle, and imply that regions that are currently characterized by higher water availability may exhibit heightened vulnerability to future drying.


Asunto(s)
Cambio Climático , Lluvia , Bosque Lluvioso , Estaciones del Año , Biomasa , Árboles , Brasil , Modelos Teóricos , Conservación de los Recursos Naturales
18.
AIDS Behav ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992229

RESUMEN

This study aimed to analyze the prevalence, sociobehavioral factors and clinical-laboratory consequences of late presentation among people living with HIV (PLHIV) in the Brazilian Amazon region. In total, 402 HIV + individuals treated at reference units in Belém city (Pará, Brazil) between 2018 and 2019 were evaluated. Late presentation was defined as a first-collection LTCD4+ count below 350 cells/µL. Sociodemographic, behavioral and clinical data were obtained from questionnaires or medical records. Th1, Th2 and Th17 cytokine profiles were evaluated by flow cytometry. Longitudinal data on viral load, T lymphocytes, and antiretroviral therapy administration were obtained from control and logistic databases. Approximately 52.73% of the participants were late presenters and sought medical care 7-12 + months after their primary HIV diagnosis. Sociobehavioral factors associated with late presentation included illicit drug use for more than 5 years, polyamory, no alcohol consumption, homosexuality, and sexual inactiveness after HIV diagnosis. Clinically, late presentation was associated with coinfection rate; polysymptomatology; high IFN-É£, IL-6 and IL-10 levels; nonresponse to antiretroviral therapy; and virological failure- and tuberculosis coinfection-motivated changes to therapy. In summary, the prevalence of late presentation in Pará in the Brazilian Amazon region is high. Delays in seeking specialized care after a primary HIV diagnosis cause medium/long-term changes in the life expectancy and health of PLHIV.

19.
J Avian Med Surg ; 38(2): 98-107, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38980819

RESUMEN

The objective of this study was to establish the pharmacokinetics of a single oral dose of trazodone in the Hispaniolan Amazon parrot (Amazona ventralis). Trazodone is a selective serotonin antagonist and reuptake inhibitor used commonly in both human and veterinary medicine as an antidepressant behavioral modification medicine. A single oral dose of compounded trazodone hydrochloride solution (20 mg/mL) at 50 mg/kg was administered to a total of 7 healthy adult Hispaniolan Amazon parrots. The 7 healthy adult parrots ranged in age from 10 to 15 years and weighed 228 to 323g. Blood was collected at baseline (2 weeks before study) and at 1, 2, 4, 6, 10, and 14 hours post-drug administration. Plasma concentrations of both trazodone and its active metabolite m-chlorophenylpiperazine (mCPP) were measured via liquid chromatography tandem mass spectrometry. Noncompartmental pharmacokinetic analysis was completed. The half-life (t1/2) ± SD of trazodone for the Hispaniolan parrots was 1.89 ± 0.49 hours, and the t1/2 ± SD of mCPP metabolite was 1.9 ± 0.55 hours. Maximum serum drug concentrations, or Cmax (ng/mL), were 738.3 ± 285.3 for trazodone. Times to achieve Cmax (hours) for trazadone and the mCPP metabolite were 1 hour and 2 hours postdosing, respectively. While this study did not establish the behavioral effects of trazodone, no adverse side effects were observed throughout the 48-hour period following drug administration and blood collection. Our results indicate that the oral administration of a 50-mg/kg single dose of trazodone to Hispaniolan parrots may be considered a safe dose. Plasma concentrations are comparable to previously published values in humans, dogs, horses, and pigeons (Columba livia domestica) for up to 14 hours following dosing. This study indicates that further studies are needed to establish the pharmacodynamics and the efficacy of trazodone in the medical management of behavioral problems in psittacine species.


Asunto(s)
Amazona , Trazodona , Animales , Trazodona/farmacocinética , Trazodona/administración & dosificación , Trazodona/sangre , Amazona/sangre , Semivida , Masculino , Área Bajo la Curva , Inhibidores Selectivos de la Recaptación de Serotonina/farmacocinética , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Inhibidores Selectivos de la Recaptación de Serotonina/sangre , Femenino , Administración Oral
20.
Braz J Microbiol ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39020098

RESUMEN

Different bioproducts can be obtained by changing operative condition of biotechnological process, and this bioprocess aspect is a significant approach to be adopted on industrial scale leading to the creation of new natural aroma. Thus, this study aimed to investigate the culture conditions and optimization of the biotransformation of limonene into limonene-1,2-diol using Pestalotiopsis mangiferae LaBMicrA-505 obtained from the Brazilian Amazon. The study started with the investigation of the establishment of culture, followed by optimization of the conditions for biotransformation of R-(+)-limonene to limonene-1,2-diol, using shake flasks. The fresh biomass of P. mangiferae LaBMicrA-505 obtained in liquid media supplemented with yeast-malt extract under with 72 h (stationary phase) performed better diol productivity when compared to other biomasses. Finally, in the modeling of contour plots and surface responses of a central composite design, the use of 4 g l- 1 biomass, 2% of the substrate at 24 °C, 120 rpm, and pH of 6.0 could maximize the production of limonene-1,2-diol, accumulated up to 98.34 ± 1.53% after 96 h of reaction. This study contributed to identified operational condition for the R-(+)-limonene bioconversion scale-up. The endophytic fungus P. mangiferae LaBMicrA-505 proved to be a potent biocatalyst to biotechnologically produce limonene-1,2-diol, an aroma compounds with interesting bioactive features that up to now has been manufactured by extraction from plants with long and not environmentally friendly procedures.

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