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1.
JPRAS Open ; 40: 85-94, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38444626

RESUMO

Introduction: Breast augmentation, a popular cosmetic surgery using devices like silicone implants, can lead to a common issue called capsular contracture (CC). This condition involves the formation of fibrous tissue around the implants and can be influenced by variables like immunological and bacterial factors. This study aimed to explore the impact of autoimmune diseases (ADs) on CC along with other factors influencing future clinical decisions. Methods: A systematic review of electronic databases was conducted using PubMed, Web of Science, Scopus, EMBASE, and involving adult patients (>18) with CC and ADs after breast surgery using MeSH terminology using a broad search strategy. All searches were performed and analyzed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and duplicates were removed with Rayyan. Two independent investigators extracted and assessed the data involving demographics and baseline data related to CC and AD. Results: The incidence of CC varied (2.3%-4.1%). Subglandular placement and older device age raised risk. SERI Surgical Scaffold complications included necrosis, seroma, hematoma, implant loss, and infection; CC was associated with necrosis. Natrelle 410 implants showed lower 10-year CC risk than round gel implants. Acellular dermal matrix implant-based breast reconstruction with radiotherapy (RT) correlated with 20.7% post-RT CC. Previous research demonstrated no significant connection between silicone gel implants and ADs. Biofilm, surgical site infection, implant features, and interventions emerged as frequent CC risk factors. Conclusion: Finding appropriate techniques to reduce the risk factors associated with CC together with providing comprehensive patient counseling on these factors will definitely improve the patient-centered outcome of breast implant surgery.

2.
Pak J Med Sci ; 39(6): 1899-1906, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936776

RESUMO

The International Cardio-Metabolic Forum held a plenary session to establish a multinational consensus on the challenges faced in diabetes management within lower-middle-income countries (LMICs) and their potential solutions. Stakeholders, including patients, family/caretakers, healthcare professionals, and healthcare policymakers & organizations, participated in discussions. The audience of 280 doctors from 15 different countries (Pakistan, Qatar, Sri Lanka, Kenya, Myanmar, Georgia, Nigeria, Philippines, Uzbekistan, Iraq, Tanzania, Cambodia, Kazakhstan, South Sudan and Libya) was divided into 4 groups led by Group Leaders to represent each stakeholder group. Questionnaires addressing key challenges and solutions specific to each group were used to facilitate consensus development. Participants voted on relevant options based on their clinical experience. SLIDO software was used for polling, generating separate results for each group. The insights shared by healthcare professionals highlighted the importance of improving medication accessibility and cost-effectiveness for patients, emphasizing the need for adherence to treatment plans and lifestyle modifications. The significance of balanced nutrition with low glycemic index food for enhancing quality of life was recognized. Caregivers of diabetic patients with comorbidities face increasing demands for care, particularly in relation to age-related milestones. Healthcare professionals emphasized the challenges posed by cultural beliefs and health awareness, underscoring the importance of teamwork and early referral for managing comorbidities. Healthcare policymakers need to focus on disease education, awareness programs, screening guidelines, and advocacy for community and clinical screening. By addressing these challenges, a more comprehensive and effective approach to diabetes management can be achieved in LMICs, ultimately improving outcomes for individuals with diabetes.

3.
Tree Physiol ; 43(10): 1731-1744, 2023 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-37471648

RESUMO

The carbon isotope composition of respired CO2 (δ13CR) and bulk organic matter (δ13CB) of various plant compartments informs about the isotopic fractionation and substrate of respiratory processes, which are crucial to advance the understanding of carbon allocation in plants. Nevertheless, the variation across organs, species and seasons remains poorly understood. Cavity Ring-Down Laser Spectroscopy was applied to measure δ13CR in leafy shoots and woody stems of maple (Acer platanoides L.), oak (Quercus robur L.) and cedar (Thuja occidentalis L.) trees during spring and late summer. Photosynthesis, respiration, growth and non-structural carbohydrates were measured in parallel to evaluate potential drivers for respiratory fractionation. The CO2 respired by maple and oak shoots was 13C-enriched relative to δ13CB during spring, but not late summer or in the stem. In cedar, δ13CR did not vary significantly throughout organs and seasons, with respired CO2 being 13C-depleted relative to δ13CB. Shoot δ13CR was positively related to leaf starch concentration in maple, while stem δ13CR was inversely related to stem growth. These relations were not significant for oak or cedar. The variability in δ13CR suggests (i) different contributions of respiratory pathways between organs and (ii) seasonality in the respiratory substrate and constitutive compounds for wood formation in deciduous species, less apparent in evergreen cedar, whose respiratory metabolism might be less variable.


Assuntos
Dióxido de Carbono , Árvores , Estações do Ano , Árvores/fisiologia , Dióxido de Carbono/metabolismo , Isótopos de Carbono/análise , Carbono/metabolismo , Folhas de Planta/metabolismo
4.
PLoS Negl Trop Dis ; 17(4): e0010862, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37043542

RESUMO

Phlebotomine sand flies are of global significance as important vectors of human disease, transmitting bacterial, viral, and protozoan pathogens, including the kinetoplastid parasites of the genus Leishmania, the causative agents of devastating diseases collectively termed leishmaniasis. More than 40 pathogenic Leishmania species are transmitted to humans by approximately 35 sand fly species in 98 countries with hundreds of millions of people at risk around the world. No approved efficacious vaccine exists for leishmaniasis and available therapeutic drugs are either toxic and/or expensive, or the parasites are becoming resistant to the more recently developed drugs. Therefore, sand fly and/or reservoir control are currently the most effective strategies to break transmission. To better understand the biology of sand flies, including the mechanisms involved in their vectorial capacity, insecticide resistance, and population structures we sequenced the genomes of two geographically widespread and important sand fly vector species: Phlebotomus papatasi, a vector of Leishmania parasites that cause cutaneous leishmaniasis, (distributed in Europe, the Middle East and North Africa) and Lutzomyia longipalpis, a vector of Leishmania parasites that cause visceral leishmaniasis (distributed across Central and South America). We categorized and curated genes involved in processes important to their roles as disease vectors, including chemosensation, blood feeding, circadian rhythm, immunity, and detoxification, as well as mobile genetic elements. We also defined gene orthology and observed micro-synteny among the genomes. Finally, we present the genetic diversity and population structure of these species in their respective geographical areas. These genomes will be a foundation on which to base future efforts to prevent vector-borne transmission of Leishmania parasites.


Assuntos
Leishmania , Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Humanos , Phlebotomus/parasitologia , Psychodidae/parasitologia , Leishmania/genética , Genômica
5.
Front Plant Sci ; 13: 855741, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401623

RESUMO

European beech (Fagus sylvatica L.) is a widespread and economically important temperate tree species in Europe. The warmer temperatures and severe drought events expected in the future, especially in Mediterranean areas, could affect the vitality and productivity of beech stands that have been intensively used in these areas in the past. Here, we aim to assess the wood anatomical responses of beech to environmental variability and silvicultural practices by investigating three beech stands along an elevational gradient (1,200 to 1,950 m a.s.l.) in the Apennines (Italy). Therefore, we quantified several anatomical traits of the xylem vessels related to tree hydraulics from five trees per stand and investigated variability between and within tree rings. Our results suggest generally limited trait plasticity, with higher plasticity of mean vessel lumen area and theoretical hydraulic conductivity, while maximum vessel size and mean hydraulic diameter were less plastic, likely because of the stronger determination by tree height. High-elevation trees were hydraulically more limited than trees at a mid and lower elevation as indicated by the more conservative anatomical configuration, i.e., comparatively smaller vessels and a 50% tighter trait coordination. Cessation of coppicing resulted in a hydraulically safer anatomy with comparatively smaller vessels at the most intensively used site (1,200 m), triggered by increased water demand due to an increase in canopy density, and thus, an increase in stand transpiration. Furthermore, maximum vessel size at the beginning showed different climate sensitivity compared to the rest of the tree ring, while intra-ring anatomical profiles showed little difference between normal and the 5 years with the highest and lowest mean temperature and precipitation. Overall, this study highlights the challenges to separate the externally induced medium- to longer-term responses from ontogenetically determined patterns. We, therefore, call for more comprehensive studies to further explore and verify the plasticity of wood anatomical traits in European beech in response to short- to long-term environmental fluctuations to gain a mechanistic understanding useful for sustainable forest ecosystems.

6.
Tree Physiol ; 41(9): 1611-1626, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-33824979

RESUMO

The Canary Islands, an archipelago east of Morocco's Atlantic coast, present steep altitudinal gradients covering various climatic zones from hot deserts to subalpine Mediterranean, passing through fog-influenced cloud forests. Unlike the majority of the Canarian flora, Pinus canariensis C. Sm. ex DC. in Buch grow along most of these gradients, allowing the study of plant functioning in contrasting ecosystems. Here we assess the water sources (precipitation, fog) of P. canariensis and its physiological behavior in its different natural environments. We analyzed carbon and oxygen isotope ratios of water and organics from atmosphere, soil and different plant organs and tissues (including 10-year annual time series of tree-ring cellulose) of six sites from 480 to 1990 m above sea level on the Canary Island La Palma. We found a decreasing δ18O trend in source water that was overridden by an increasing δ18O trend in needle water, leaf assimilates and tree-ring cellulose with increasing altitude, suggesting site-specific tree physiological responses to relative humidity. Fog-influenced and fog-free sites showed similar δ13C values, suggesting photosynthetic activity to be limited by stomatal closure and irradiance at certain periods. In addition, we observed an 18O-depletion (fog-free and timberline sites) and 13C-depletion (fog-influenced and fog-free sites) in latewood compared with earlywood caused by seasonal differences in: (i) water uptake (i.e., deeper ground water during summer drought, fog water frequency and interception) and (ii) meteorological conditions (stem radial growth and latewood δ18O correlated with winter precipitation). In addition, we found evidence for foliar water uptake and strong isotopic gradients along the pine needle axis in water and assimilates. These gradients are likely the reason for an unexpected underestimation of pine needle water δ18O when applying standard leaf water δ18O models. Our results indicate that soil water availability and air humidity conditions are the main drivers of the physiological behavior of pine along the Canary Island's altitudinal gradients.


Assuntos
Pinus , Água , Isótopos de Carbono/análise , Ecossistema , Isótopos de Oxigênio/análise , Espanha , Árvores
7.
J Med Entomol ; 57(6): 1722-1734, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32761144

RESUMO

The antennal sensilla and the antenna of females Nyssomyia intermedia, one of the main vectors of American cutaneous leishmaniasis, were studied by scanning electron microscopy. The main goal was to characterize the quantity, typology, and topography of the sensilla with particular attention to the olfactory types. The insects were captured in the city of Corte de Pedra, State of Bahia, Brazil, by CDC-type light traps and raised in a laboratory as a new colony. Fourteen well-differentiated sensilla were identified, among six cuticular types: trichoidea, campaniformia, squamiformia, basiconica, chaetica, and coeloconica. Of these, six sensilla were classified as olfactory sensilla due to their specific morphological features. Smaller noninnervated pilosities of microtrichiae type were also evidenced by covering all antennal segments. The antennal segments differ in shapes and sizes, and the amount and distribution of types and subtypes of sensilla. This study may foment future taxonomic and phylogenetic analysis for a better evolutionary understanding of the sand flies. Besides, it may assist the targeting of future electrophysiological studies by Single Sensillum Recording, and aim to develop alternative measures of monitoring and control of this vector.


Assuntos
Antenas de Artrópodes/ultraestrutura , Insetos Vetores/ultraestrutura , Psychodidae/ultraestrutura , Animais , Brasil , Feminino , Leishmaniose Cutânea , Microscopia Eletrônica de Varredura , Sensilas/ultraestrutura
8.
Tree Physiol ; 40(12): 1697-1711, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-32722795

RESUMO

Insect defoliation impacts forest productivity worldwide, highlighting the relevance of plant-insect interactions. The larch budmoth (Zeiraphera griseana Hübner) is one of the most extensively studied defoliators, where numerous tree ring-based analyses on its host (Larix decidua Mill.) have aided in identifying outbreak dynamics over the past millennia. Yet, outbreaks have been widely absent after the early 1980s, and little is known about the in situ tree physiological responses and the allocation of carbon resources during and after defoliation. In summer 2018, we tracked an ongoing larch budmoth outbreak in a well-studied larch forest in the Swiss Alps. We performed biweekly monitoring on an affected and unaffected site using a unique combination of xylogenesis observations, measurements of non-structural carbohydrates, isotopic analysis of needle assimilates and ground-based and remote-sensed leaf trait observations. The budmoth induced a defoliation that lasted 40 days and could be detected by satellite observations. Soluble sugars significantly decreased in needles and stem phloem of the defoliated trees, while starch levels remained stable in the stem and root xylem compared to the control. Carbon and oxygen isotope ratios in needle assimilates indicated that neither photosynthetic assimilation rates nor stomatal conductance was different between sites before, during and after the outbreak. Defoliated trees ceased cell wall thickening 17 days earlier than unaffected trees, showing the earliest halt of ring formation recorded from 2007 untill 2013 and causing significant thinner cell walls, particularly in the latewood. No significant differences were found for cell enlargement rates and ring width. Our study revealed that an outbreak causes a downregulation of cell wall thickening first, while no starch is mobilized or leaf physiology is adjusted to compensate for the reduced carbon source due to defoliation. Our observations suggest that affected larch trees prioritize leaf recovery and carbon storage over wood biomass development.


Assuntos
Larix , Animais , Carbono , Surtos de Doenças , Monitorização Fisiológica , Folhas de Planta , Árvores , Madeira
9.
Molecules ; 24(16)2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31443290

RESUMO

Background. There is no gold standard method for human skin odor determination; several techniques can be applied to collect, extract, transfer, and detect human skin odors. However, none of these methods are suitable for field sampling of a large number of individuals. Objective. The present study aimed to develop a simple, fast, non-invasive, and low-cost method for such a purpose. Methods. Considering that hair from legs can act as a retention mesh of volatile organic compounds (VOCs), samples of leg hairs provided by healthy adult males were collected and solid-phase microextraction (SPME), in headspace (HS) mode, coupled to gas chromatography (GC) and mass spectrometry (MS) analysis of the samples was carried out. A pilot test was applied to detect five quality markers that are frequently reported in human skin odors. Then, several steps were performed for method standardization. The method was applied to 36 different individuals (3 sampled under laboratory conditions and 33 under field conditions), aiming to evaluate its applicability in both environments. Findings. A total of 49 VOCs were identified, and 73.5% of these have been reported in previous studies. Main Conclusions. Hair from legs can be considered an efficient tool for human skin odor sampling and a suitable and practical matrix for human skin odor profile determination by using HS-SPME/GC-MS.


Assuntos
Cabelo/química , Odorantes/análise , Pele/metabolismo , Análise de Variância , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
10.
PLoS One ; 13(9): e0203989, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30248113

RESUMO

BACKGROUND: Many studies have investigated what could attract insects of medical importance and a crucial role has lately been attributed to human skin odors. Most of these researches have been concerned with mosquitoes, e.g., vectors of dengue and malaria. Little is known about volatile organic compounds (VOCs) from human skin odors and their effects on leishmania vectors. OBJECTIVE: The present study aimed to identify the VOCs from human skin that can be attractive to female anthropophilic phlebotomine sandflies. RESULTS: Forty-two VOCs were identified from skin odors of 33 male volunteers, seven of which were tested in wind tunnel assays employing field-captured phlebotomine sandflies (75.4% identified as Lutzomyia intermedia). Hexane and (E)-oct-3-en-1-ol (octenol) were used as negative and positive controls, respectively. 2-Phenylacetaldehyde (hereafter called phenylacetaldehyde), 6-methylhept-5-en-2-one (also known as sulcatone), nonadecane and icosane were found to activate female phlebotomine sandflies, but only phenylacetaldehyde, 6-methylhepten-5-en-2-one and icosane elicited attraction responses. CONCLUSIONS: These results suggest that phenylacetaldehyde, 6-methylhepten-5-en-2-one and icosane may be suitable candidates for attractiveness experimentation in the field which can be an important tool to develop strategies concerning human beings protection against phlebotomine sandflies bites and consequently against leishmaniasis.


Assuntos
Insetos Vetores/fisiologia , Insetos Vetores/parasitologia , Leishmaniose Cutânea/transmissão , Odorantes/análise , Psychodidae/fisiologia , Psychodidae/parasitologia , Pele/química , Acetaldeído/análogos & derivados , Acetaldeído/análise , Adolescente , Adulto , Alcanos/análise , Animais , Brasil , Doenças Endêmicas , Feminino , Humanos , Mordeduras e Picadas de Insetos/prevenção & controle , Cetonas/análise , Leishmania/patogenicidade , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/prevenção & controle , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Adulto Jovem
11.
ISME J ; 12(4): 1061-1071, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29476139

RESUMO

Changes in frequency and amplitude of rain events, that is, precipitation patterns, result in different water conditions with soil depth, and likely affect plant growth and shape plant and soil microbial activity. Here, we used 18O stable isotope probing (SIP) to investigate bacterial and fungal communities that actively grew or not upon rewetting, at three different depths in soil mesocosms previously subjected to frequent or infrequent watering for 12 weeks (equal total water input). Phylogenetic marker genes for bacteria and fungi were sequenced after rewetting, and plant-soil microbial coupling documented by plant 13C-CO2 labeling. Soil depth, rather than precipitation pattern, was most influential in shaping microbial response to rewetting, and had differential effects on active and inactive bacterial and fungal communities. After rewetting, active bacterial communities were less rich, more even and phylogenetically related than the inactive, and reactivated throughout the soil profile. Active fungal communities after rewetting were less abundant and rich than the inactive. The coupling between plants and soil microbes decreased under infrequent watering in the top soil layer. We suggest that differences in fungal and bacterial abundance and relative activity could result in large effects on subsequent soil biogeochemical cycling.


Assuntos
Bactérias/classificação , Fungos/classificação , Microbiologia do Solo , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Filogenia , Desenvolvimento Vegetal , Chuva , Solo/química
12.
AoB Plants ; 10(6): ply070, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30619543

RESUMO

Climatic seasonality drives ecosystem processes (e.g. productivity) and influences plant species distribution. However, it is poorly understood how different aspects of seasonality (especially regarding temperature and precipitation) affect growth continuity of trees in climates with low seasonality because seasonality is often only crudely measured. On islands, exceptionally wide elevational species distribution ranges allow the use of tree rings to identify how growth continuity and climate-growth relationships change with elevation. Here, we present a novel dendroecological method to measure stem growth continuity based on annual density fluctuations (ADFs) in tree rings of Pinus canariensis to indicate low climatic seasonality. The species ranges from 300 to >2000 m a.s.l. on the trade wind-influenced island of La Palma (Canary Islands), where we measured three decades of tree-ring data of 100 individuals distributed over 10 sites along the entire elevational range. The successfully implemented ADF approach revealed a major shift of stem growth continuity across the elevational gradient. In a remarkably clear pattern, stem growth continuity (percentage of ADFs) showed a hump-shaped relationship with elevation reaching a maximum at around 1000 m a.s.l. Low- to mid-elevation tree growth was positively correlated with the Palmer Drought Severity Index (PDSI; indicating aridity) and sea surface temperature (indicating trade wind-influenced moderation of water supply), while high-elevation tree growth was positively correlated with winter temperature (indicating a cold-induced dormancy period). We conclude that ADFs are a useful method to measure stem growth continuity in low-seasonality climates. Growth of P. canariensis on the Canary Islands is more frequently interrupted by winter cold at high elevations and by summer drought at low elevations than in the trade wind-influenced mid elevations, where growth sometimes continues throughout the year. Climate change-associated alterations in trade wind cloud formation might cause non-analogue growth limitations for many unique island species.

13.
Sci Rep ; 7(1): 3149, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28600554

RESUMO

Sand flies inject saliva while feeding in the vertebrate host and anti-saliva antibodies can be used as biomarkers of exposure to Leishmania vectors. We expressed recombinant salivary proteins from Lutzomyia intermedia, a vector of Leishmania braziliensis, and evaluated the seroreactivity in exposed individuals in search for exposure markers. We found a strong correlation among positive serology to recombinant proteins LinB-13, 26, 15, 21 and to salivary proteins: rLinB-13 was the top performing molecule; IgG4 was the most predominant antibody subclass and antibodies to rLinB-13 did not cross react with Lu. longipalpis salivary proteins. By evaluating a cohort of contacts of CL patients, we confirmed that rLinB-13, an antigen 5-related protein, is a marker of exposure to Lu. intermedia with high degree of accuracy. In a 5-year follow up, we determined that individuals who developed CL presented higher anti-rLinB13 IgG responses, before the appearance of clinical symptoms. They also presented a lower frequency of cellular responses to the parasite (DTH). Our results show that seroconversion to a salivary molecule, rLinB-13, is a marker of risk for CL development caused by Leishmania braziliensis. This highlight the possibility of developing tools based on vector molecules to manage the disease in endemic areas.


Assuntos
Doenças Endêmicas , Imunoglobulina G/sangue , Proteínas de Insetos/sangue , Insetos Vetores/química , Leishmaniose Cutânea/diagnóstico , Psychodidae/química , Proteínas e Peptídeos Salivares/sangue , Animais , Biomarcadores/sangue , Brasil/epidemiologia , Diagnóstico Precoce , Humanos , Soros Imunes/química , Immunoblotting/métodos , Proteínas de Insetos/genética , Proteínas de Insetos/imunologia , Insetos Vetores/imunologia , Leishmania braziliensis/patogenicidade , Leishmania braziliensis/fisiologia , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/imunologia , Psychodidae/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/imunologia , Soroconversão
14.
PLoS Negl Trop Dis ; 10(11): e0005078, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27812113

RESUMO

BACKGROUND: Previous works showed that immunization with saliva from Lutzomyia intermedia, a vector of Leishmania braziliensis, does not protect against experimental infection. However, L. braziliensis is also transmitted by Lutzomyia whitmani, a sand fly species closely related to Lu. intermedia. Herein we describe the immune response following immunization with Lu. whitmani saliva and the outcome of this response after L. braziliensis infection. METHODS AND FINDINGS: BALB/c mice immunized with Lu. whitmani saliva developed robust humoral and cellular immune responses, the latter characterized by an intense cellular infiltrate and production of IFN-γ and IL-10, by both CD4+ and CD8+ cells. Mice immunized as above and challenged with L. braziliensis plus Lu. whitmani saliva displayed significantly smaller lesions and parasite load at the challenge site. This protection was associated with a higher (p<0.05) IFN-γ production in response to SLA stimulation. Long-term persisting immunity was also detected in mice immunized with Lu. whitmani saliva. Furthermore, individuals residing in an endemic area for cutaneous leishmaniasis (CL) presented antibody responses to Lu. whitmani saliva. However CL patients, with active lesions, displayed a lower humoral response to Lu. whitmani saliva compared to individuals with subclinical Leishmania infection. CONCLUSION: Pre-exposure to Lu. whitmani saliva induces protection against L. braziliensis in a murine model. We also show that Lu. whitmani salivary proteins are immunogenic in naturally exposed individuals. Our results reinforce the importance of investigating the immunomodulatory effect of saliva from different species of closely related sand flies.


Assuntos
Insetos Vetores/imunologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/imunologia , Psychodidae/imunologia , Saliva/imunologia , Proteínas e Peptídeos Salivares/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunização , Imunoglobulina G/sangue , Imunomodulação , Insetos Vetores/parasitologia , Interferon gama/imunologia , Interleucina-10/imunologia , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Estudos Prospectivos , Psychodidae/parasitologia , Saliva/química
15.
Parasit Vectors ; 9: 480, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27581188

RESUMO

BACKGROUND: Parasites of the genus Leishmania cause a broad spectrum of diseases, collectively known as leishmaniasis, in humans worldwide. American cutaneous leishmaniasis is a neglected disease transmitted by sand fly vectors including Lutzomyia intermedia, a proven vector. The female sand fly can acquire or deliver Leishmania spp. parasites while feeding on a blood meal, which is required for nutrition, egg development and survival. The microbiota composition and abundance varies by food source, life stages and physiological conditions. The sand fly microbiota can affect parasite life-cycle in the vector. METHODS: We performed a metagenomic analysis for microbiota composition and abundance in Lu. intermedia, from an endemic area in Brazil. The adult insects were collected using CDC light traps, morphologically identified, carefully sterilized, dissected under a microscope and the females separated into groups according to their physiological condition: (i) absence of blood meal (unfed = UN); (ii) presence of blood meal (blood-fed = BF); and (iii) presence of developed ovaries (gravid = GR). Then, they were processed for metagenomics with Illumina Hiseq Sequencing in order to be sequence analyzed and to obtain the taxonomic profiles of the microbiota. RESULTS: Bacterial metagenomic analysis revealed differences in microbiota composition based upon the distinct physiological stages of the adult insect. Sequence identification revealed two phyla (Proteobacteria and Actinobacteria), 11 families and 15 genera; 87 % of the bacteria were Gram-negative, while only one family and two genera were identified as Gram-positive. The genera Ochrobactrum, Bradyrhizobium and Pseudomonas were found across all of the groups. CONCLUSIONS: The metagenomic analysis revealed that the microbiota of the Lu. intermedia female sand flies are distinct under specific physiological conditions and consist of 15 bacterial genera. The Ochrobactrum, Bradyrhizobium and Pseudomonas were the common genera. Our results detailing the constituents of Lu. intermedia native microbiota contribute to the knowledge regarding the bacterial community in an important sand fly vector and allow for further studies to better understand how the microbiota interacts with vectors of human parasites and to develop tools for biological control.


Assuntos
Bactérias/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenômica/métodos , Psychodidae/microbiologia , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Feminino
16.
Parasit Vectors ; 7: 601, 2014 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-25526785

RESUMO

BACKGROUND: Eicosanoids and sand fly saliva have a critical role in the Leishmania infection. Here, we evaluated the effect of Lutzomyia longipalpis salivary gland sonicate (SGS) on neutrophil and monocyte recruitment and activation of eicosanoid production in a murine model of inflammation. METHODS: C57BL/6 mice were inoculated intraperitonealy with Lutzomyia longipalpis SGS or Leishmania infantum or both, followed by analyses of cell recruitment, parasite load and eicosanoid production. RESULTS: Intraperitoneal injection of Lutzomyia longipalpis SGS together with Leishmania infantum induced an early increased parasite viability in monocytes and neutrophils. L. longipalpis SGS increased prostaglandin E2 (PGE2), but reduced leukotriene B4 (LTB4) production ex vivo in peritoneal leukocytes. In addition, the pharmacological inhibition of cyclooxygenase 2 (COX-2) with NS-398 decreased parasite viability inside macrophages during Leishmania infection in the presence of L. longipalpis SGS arguing that PGE2 production is associated with diminished parasite killing. CONCLUSIONS: These findings indicate that L. longipalpis SGS is a critical factor driving immune evasion of Leishmania through modulation of PGE2/LTB4 axis, which may represent an important mechanism on establishment of the infection.


Assuntos
Dinoprostona/imunologia , Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Leucotrieno B4/imunologia , Psychodidae/imunologia , Animais , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Modelos Animais de Doenças , Feminino , Humanos , Leishmaniose Visceral/parasitologia , Leucócitos/parasitologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitrobenzenos/farmacologia , Psychodidae/parasitologia , Glândulas Salivares/imunologia , Sulfonamidas/farmacologia
17.
PLoS Negl Trop Dis ; 8(1): e2627, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24421912

RESUMO

During a blood meal, Lutzomyia intermedia sand flies transmit Leishmania braziliensis, a parasite causing tegumentary leishmaniasis. In experimental leishmaniasis, pre-exposure to saliva of most blood-feeding sand flies results in parasite establishment in absence of any skin damages in mice challenged with dermotropic Leishmania species together with saliva. In contrast, pre-immunization with Lu. intermedia salivary gland sonicate (SGS) results in enhanced skin inflammatory exacerbation upon co-inoculation of Lu. intermedia SGS and L. braziliensis. These data highlight potential unique features of both L. braziliensis and Lu. intermedia. In this study, we investigated the genes modulated by Lu. intermedia SGS immunization to understand their potential impact on the subsequent cutaneous immune response following inoculation of both SGS and L. braziliensis. The cellular recruitment and global gene expression profile was analyzed in mice repeatedly inoculated or not with Lu. intermedia. Microarray gene analysis revealed the upregulation of a distinct set of IFN-inducible genes, an immune signature not seen to the same extent in control animals. Of note this INF-inducible gene set was not induced in SGS pre-immunized mice subsequently co-inoculated with SGS and L. braziliensis. These data suggest the parasite prevented the upregulation of this Lu. intermedia saliva-related immune signature. The presence of these IFN-inducible genes was further analyzed in peripheral blood mononuclear cells (PBMCs) sampled from uninfected human individuals living in a L. braziliensis-endemic region of Brazil thus regularly exposed to Lu. intermedia bites. PBMCs were cultured in presence or absence of Lu. intermedia SGS. Using qRT-PCR we established that the IFN-inducible genes induced in the skin of SGS pre-immunized mice, were also upregulated by SGS in PBMCs from human individuals regularly exposed to Lu. intermedia bites, but not in PBMCs of control subjects. These data demonstrate that repeated exposure to Lu. intermedia SGS induces the expression of potentially host-protective IFN-inducible genes.


Assuntos
Interações Hospedeiro-Parasita , Leishmania braziliensis/imunologia , Psychodidae/imunologia , Saliva/imunologia , Animais , Brasil , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Humanos , Interferons/imunologia , Leucócitos Mononucleares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real
18.
Sci Rep ; 3: 2352, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23912591

RESUMO

Leishmania infantum chagasi causes visceral leishmaniasis (VL); it is transmitted by the sand fly Lutzomyia longipalpis that injects saliva and parasites into the host's skin during a blood meal. Chickens represent an important blood source for sand flies and their presence in the endemic area is often cited as a risk factor for VL transmission. However, the role of chickens in VL epidemiology has not been well defined. Here, we tested if chicken antibodies against Lu. longipalpis salivary gland sonicate (SGS) could be used as markers of exposure to sand fly bites. All naturally exposed chickens in a VL endemic area in Brazil developed anti-SGS IgY antibodies. Interestingly, Lu. longipalpis recombinant salivary proteins rLJM17 and rLJM11 were also able to detect anti-SGS IgY antibodies. Taken together, these results show that chickens can be used to monitor the presence of Lu. longipalpis in the peri-domiciliary area in VL endemic regions, when used as sentinel animals.


Assuntos
Biomarcadores/sangue , Galinhas/imunologia , Leishmaniose Visceral/sangue , Leishmaniose Visceral/epidemiologia , Leishmaniose/sangue , Leishmaniose/epidemiologia , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/epidemiologia , Vigilância de Evento Sentinela/veterinária , Animais , Brasil/epidemiologia , Exposição Ambiental/análise , Leishmaniose/imunologia , Doenças das Aves Domésticas/imunologia , Prevalência , Medição de Risco , Testes Sorológicos/estatística & dados numéricos
19.
Naturwissenschaften ; 100(8): 739-47, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23760570

RESUMO

Mercury (Hg) is a toxic element that is emitted to the atmosphere by both human activities and natural processes. Volcanic emissions are considered a natural source of mercury in the environment. In some cases, tree ring records taken close to volcanoes and their relation to volcanic activity over time are contradictory. In 1949, the Hoyo Negro volcano (La Palma-Canary Islands) produced significant pyroclastic flows that damaged the nearby stand of Pinus canariensis. Recently, 60 years after the eruption, we assessed mercury concentrations in the stem of a pine which survived volcano formation, located at a distance of 50 m from the crater. We show that Hg content in a wound caused by pyroclastic impacts (22.3 µg kg(-1)) is an order of magnitude higher than the Hg concentrations measured in the xylem before and after the eruption (2.3 µg kg(-1)). Thus, mercury emissions originating from the eruption remained only as a mark-in pyroclastic wounds-and can be considered a sporadic and very high mercury input that did not affect the overall Hg input in the xylem. In addition, mercury contents recorded in the phloem (9.5 µg kg(-1)) and bark (6.0 µg kg(-1)) suggest that mercury shifts towards non-living tissues of the pine, an aspect that can be related to detoxification in volcanism-adapted species.


Assuntos
Mercúrio/análise , Pinus/metabolismo , Poluentes Ambientais/análise , Poluentes Ambientais/metabolismo , Mercúrio/metabolismo , Floema/química , Pinus/química , Casca de Planta/química , Espanha , Erupções Vulcânicas , Xilema/química
20.
PLoS Negl Trop Dis ; 7(5): e2242, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717705

RESUMO

BACKGROUND: Leishmania parasites are transmitted in the presence of sand fly saliva. Together with the parasite, the sand fly injects salivary components that change the environment at the feeding site. Mice immunized with Phlebotomus papatasi salivary gland (SG) homogenate are protected against Leishmania major infection, while immunity to Lutzomyia intermedia SG homogenate exacerbated experimental Leishmania braziliensis infection. In humans, antibodies to Lu. intermedia saliva are associated with risk of acquiring L. braziliensis infection. Despite these important findings, there is no information regarding the repertoire of Lu. intermedia salivary proteins. METHODS AND FINDINGS: A cDNA library from the Salivary Glands (SGs) of wild-caught Lu. intermedia was constructed, sequenced, and complemented by a proteomic approach based on 1D SDS PAGE and mass/mass spectrometry to validate the transcripts present in this cDNA library. We identified the most abundant transcripts and proteins reported in other sand fly species as well as novel proteins such as neurotoxin-like proteins, peptides with ML domain, and three small peptides found so far only in this sand fly species. DNA plasmids coding for ten selected transcripts were constructed and used to immunize BALB/c mice to study their immunogenicity. Plasmid Linb-11--coding for a 4.5-kDa protein--induced a cellular immune response and conferred protection against L. braziliensis infection. This protection correlated with a decreased parasite load and an increased frequency of IFN-γ-producing cells. CONCLUSIONS: We identified the most abundant and novel proteins present in the SGs of Lu. intermedia, a vector of cutaneous leishmaniasis in the Americas. We also show for the first time that immunity to a single salivary protein from Lu. intermedia can protect against cutaneous leishmaniasis caused by L. braziliensis.


Assuntos
Perfilação da Expressão Gênica , Proteínas de Insetos/biossíntese , Leishmania braziliensis/imunologia , Psychodidae/genética , América , Animais , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Feminino , Biblioteca Gênica , Humanos , Imunidade Celular , Proteínas de Insetos/genética , Proteínas de Insetos/imunologia , Proteínas de Insetos/isolamento & purificação , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/prevenção & controle , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Proteoma/análise , Psychodidae/imunologia , Psychodidae/parasitologia , Proteínas e Peptídeos Salivares/biossíntese , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/imunologia , Proteínas e Peptídeos Salivares/isolamento & purificação
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