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1.
J Hazard Mater ; 471: 134303, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38669921

ABSTRACT

Despite the widespread use of biochar for soil and sediment remediation, little is known about the impact of pyrolysis temperature on the biogeochemistry of arsenic (As) and lead (Pb) and microorganisms in sediment under reducing conditions. In this study, we investigated the effects of pyrolysis temperature and the addition of glucose on the release and transformation of As and Pb, as well as their potential effects on the bacterial community in contaminated sediments. The addition of biochar altered the geochemical cycle of As, as it favors specific bacterial groups capable of changing species from As(V) to As(III) through fermentation, sulfate respiration and nitrate reduction. The carbon quality and content of N and S in solution shaped the pH and redox potential in a way that changed the microbial community, favoring Firmicutes and reducing Proteobacteria. This change played a fundamental role in the reductive dissolution of As and Pb minerals. The addition of biochar was the only efficient way to remove Pb, possibly as a function of its sorption and precipitation mechanisms. Such insights could contribute to the production or choice of high-efficiency biochar for the remediation of sediments subjected to redox conditions.


Subject(s)
Arsenic , Charcoal , Geologic Sediments , Lead , Mining , Oxidation-Reduction , Charcoal/chemistry , Arsenic/chemistry , Arsenic/analysis , Arsenic/metabolism , Geologic Sediments/microbiology , Geologic Sediments/chemistry , Lead/chemistry , Pyrolysis , Bacteria/metabolism , Soil Pollutants/chemistry , Soil Pollutants/metabolism , Temperature
2.
PLoS Negl Trop Dis ; 18(1): e0011789, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38241360

ABSTRACT

Domestic dogs are the primary urban reservoirs of Leishmania infantum, the causative agent of visceral leishmaniasis. In Canine Leishmaniasis (CanL), modulation of the host's immune response may be associated with the expression of small non-coding RNAs called microRNA (miR). miR-194 expression increases in peripheral blood mononuclear cells (PBMCs) of dogs with leishmaniasis with a positive correlation with the parasite load and in silico analysis demonstrated that the TRAF6 gene is the target of miR-194 in PBMCs from diseased dogs. Here, we isolated PBMCs from 5 healthy dogs and 28 dogs with leishmaniasis, naturally infected with L. infantum. To confirm changes in miR-194 and TRAF6 expression, basal expression of miR-194 and gene expression of TRAF6 was measured using qPCR. PBMCs from healthy dogs and dogs with leishmaniasis were transfected with miR-194 scramble, mimic, and inhibitor and cultured at 37° C, 5% CO2 for 48 hours. The expression of possible targets was measured: iNOS, NO, T-bet, GATA3, and FoxP3 were measured using flow cytometry; the production of cytokines IL-1ß, IL-4, IL-6, IL-10, TNF-α, IFN-γ, and TGF-ß in cell culture supernatants was measured using capture enzyme-linked immunosorbent assays (ELISA). Parasite load was measured using cytometry and qPCR. Functional assays followed by miR-194 inhibitor and IL-1ß blockade and assessment of NO production were also performed. Basal miR-194 expression was increased in PBMC from dogs with Leishmaniasis and was negatively correlated with TRAF6 expression. The mimic of miR-194 promoted an increase in parasite load. There were no significant changes in T-bet, GATA3, or FoxP3 expression with miR-194 enhancement or inhibition. Inhibition of miR-194 increased IL-1ß and NO in PBMCs from diseased dogs, and blockade of IL-1ß following miR-194 inhibition decreased NO levels. These findings suggest that miR-194 is upregulated in PBMCs from dogs with leishmaniasis and increases parasite load, possibly decreasing NO production via IL-1ß. These results increase our understanding of the mechanisms of evasion of the immune response by the parasite and the identification of possible therapeutic targets.


Subject(s)
Dog Diseases , Leishmania infantum , Leishmaniasis, Visceral , Leishmaniasis , MicroRNAs , Animals , Dogs , Cytokines/genetics , Dog Diseases/parasitology , Forkhead Transcription Factors , Leishmania infantum/physiology , Leishmaniasis, Visceral/genetics , Leishmaniasis, Visceral/veterinary , Leukocytes, Mononuclear , MicroRNAs/genetics , Nitric Oxide/metabolism , Parasite Load , TNF Receptor-Associated Factor 6 , Leishmaniasis/veterinary , Interleukin-1beta/metabolism
3.
Zool Stud ; 62: e36, 2023.
Article in English | MEDLINE | ID: mdl-37772162

ABSTRACT

Brakemyia metallica gen. et sp. nov. (Diptera, Milichiidae) is described and illustrated based on male and female specimens reared from carton nests of the ant Azteca aff. chartifex Forel (Formicidae: Dolichoderinae). The new genus is widely distributed in the Brazilian Amazon, and it can be readily distinguished from the other Neotropical genera by the broadened lunule, which extends well posterior of the antennae, and the hypandrial complex parallel to epandrium.

4.
J Hazard Mater ; 460: 132308, 2023 10 15.
Article in English | MEDLINE | ID: mdl-37639794

ABSTRACT

Biochar is widely used for water and soil remediation in part because of its local availability and low production cost. However, its effectiveness depends on physicochemical properties related to its feedstock and pyrolysis temperature, as well as the environmental conditions of its use site. Furthermore, biochar is susceptible to natural aging caused by changes in soil or sediment moisture, which can alter its redox properties and interactions with contaminants such as arsenic (As). In this study, we investigated the effect of pyrolysis temperature and biochar application on the release and transformations of As in contaminated sediments subjected to redox fluctuations. Biochar application and pyrolysis temperature played an important role in As species availability, As methylation, and dissolved organic carbon concentration. Furthermore, successive flooding cycles that induced reductive conditions in sediments increased the As content in the solution by up to seven times. In the solid phase, the application of biochar and the flooding cycle altered the spatial distribution and speciation of carbon, iron (Fe) and As. In general, the application of biochar decreased the reduction of Fe(III) and As(V) after the first cycle of flooding. Our results demonstrate that the flooding cycle plays an important role in the reoxidation of biochar to the point of enhancing the immobilization of As.


Subject(s)
Arsenic , Ferric Compounds , Pyrolysis , Temperature , Soil
5.
Vet Parasitol ; 320: 109958, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37269731

ABSTRACT

Leishmania infantum causes visceral leishmaniosis, a neglected tropical disease that can modulate the host immune response by altering the expression of small non-coding RNAs called microRNAs (miRNAs). Some miRNAs are differentially expressed in peripheral blood mononuclear cells (PBMCs) of dogs with canine visceral leishmaniosis (CanL), like the down-regulated miR-150. Even though miR-150 is negatively correlated with L. infantum parasitic load, it is unclear if miR-150 directly affects L. infantum parasitic load and (if so) how this miRNA would contribute to infection. Here, we isolated PBMCs from 14 naturally infected dogs (CanL group) and six healthy dogs (Control group) and treated them in vitro with miR-150 mimic or inhibitor. We measured L. infantum parasitic load using qPCR and compared treatments. We also measured miR-150 in silico predicted target protein levels (STAT1, TNF-α, HDAC8, and GZMB) using flow cytometry or enzyme-linked immunosorbent assays. Increasing miR-150 activity diminished L. infantum parasitic load in CanL PBMCs. We also found that inhibition of miR-150 reduced GZMB (granzyme B) levels. These findings demonstrate that miR-150 plays an important role in L. infantum infection in canine PBMCs, and they merit further studies aiming at drug development.


Subject(s)
Dog Diseases , Leishmania infantum , Leishmaniasis, Visceral , MicroRNAs , Animals , Dogs , Leukocytes, Mononuclear , Granzymes , Leishmaniasis, Visceral/parasitology , Leishmaniasis, Visceral/veterinary , MicroRNAs/genetics , Dog Diseases/parasitology
6.
Front Genet ; 14: 1106496, 2023.
Article in English | MEDLINE | ID: mdl-37124626

ABSTRACT

Canine Visceral leishmaniasis (CanL) poses a severe public health threat in several countries. Disease progression depends on the degree of immune response suppression. MicroRNAs (miRs) modulate mRNA translation into proteins and regulate various cellular functions and pathways associated with immune responses. MiR-21 and miR-148a can alter the parasite load and M1 macrophages are the principal cells in dogs' leishmanicidal activity. A previous study found increased miR-21 and miR-148a in splenic leukocytes (SL) of dogs with CanL using microarray analysis and in silico analysis identified PTEN pathway targets. PTEN is involved in the immune regulation of macrophages. We measured PTEN and the production of reactive oxygen species (ROS) and nitric oxide (NO) before and after transfection SLs of dogs with CanL with mimic and inhibition of miR-21 and miR-148a. PTEN levels increased, NO and ROS decreased in SLs from dogs with CanL. Inhibition of miRNA-21 resulted in PTEN increase; in contrast, PTEN decreased after miR-148a inhibition. Nitrite (NO2) levels increased after transfection with miR-21 inhibitor but were decreased with miR-148a inhibitor. The increase in miR-21 promoted a reduction in ROS and NO levels, but miR-148a inhibition increased NO and reduced ROS. These findings suggest that miR-21 and miR-148a can participate in immune response in CanL, affecting PTEN, NO, and ROS levels.

7.
Zootaxa ; 5254(2): 181-208, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-37044727

ABSTRACT

The Neotropical species of Hercostomus Loew are revised and the following new combinations are proposed: Paraclius panamensis (Van Duzee, 1931) comb. nov. (Panama), P. plumitarsis (Parent, 1931) comb. nov. (Bolivia), P. problematicus (Parent, 1930) comb. nov. (Brazil and Guyana) and Tachytrechus flavimanus (Van Duzee, 1934) comb. nov. (Brazil, Ecuador and Guyana). The type of Hercostomus petulans Parent, 1939 is lost, the species cannot be confidently identified and is here treated as a nomen dubium. As a result, the genus Hercostomus is formally excluded from the Neotropical Region. Paraclius problematicus comb. nov., P. latipes (Aldrich) and Tachytrechus flavimanus comb. nov. are redescribed based on additional material and photographs of type specimens. In addition, Paraclius maculipennis (Van Duzee, 1934) is regarded as a junior synonym of P. problematicus comb. nov. A new species of Paraclius from Costa Rica, P. norrbomi sp. nov. is described in the newly proposed latipes-group, along with P. aberrans Robinson, P. latipes and P. panamensis comb. nov.


Subject(s)
Diptera , Animals
8.
Zootaxa ; 5231(1): 37-51, 2023 Jan 26.
Article in English | MEDLINE | ID: mdl-37044820

ABSTRACT

The species of Paraclius Loew with bi-lamellate arista-like stylus are revised and P. americanus (Schiner, 1868) comb. nov. is transferred from Tachytrechus Haliday and regarded as the senior synonym of P. diplacocerus Capellari, 2013 syn. nov. In addition, two new species with similar antennal morphology are described and illustrated from Brazil: P. bilamellatus sp. nov. (States of Espírito Santo and Goiás) and P. vulcanoae sp. nov. (State of São Paulo). A distribution map and a key to the males of known species of Paraclius with bi-lamellate arista-stylus are provided.


Subject(s)
Diptera , Male , Animals , Diptera/anatomy & histology , Brazil , Animal Distribution
9.
Sci Total Environ ; 865: 161286, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36587679

ABSTRACT

Water contamination by arsenic (As) affects millions of people around the world, making techniques to immobilize or remove this contaminant a pressing societal need. Biochar and iron (oxyhydr)oxides [in particular, biogenic iron (oxyhydr)oxides (BIOS)] offer the possibility of stabilizing As in remediation systems. However, little is known about the potential antagonism in As sorption generated by the dissolved organic carbon (DOC) from biochar, or whether DOC affects how As(V) interacts with BIOS. For this reason, our objectives were to evaluate the i) As(V) sorption potential in BIOS when there is presence of DOC from pyrolyzed biochars at different temperatures; and ii) identify whether the presence of DOC alters the surface complexes formed by As(V) sorbed in the BIOS. We conducted As(V) sorption experiments with BIOS at circumneutral pH conditions and in the presence of DOC from sugarcane (Saccharum officinarum) straw biochar at pyrolyzed 350 (BC350) and 750 °C (BC750). The As(V) content was quantified by inductively coupled plasma mass spectrometry, and the BIOS structure and As(V) sorption mechanisms were investigated by X-ray absorption spectroscopy. In addition, the organic moieties comprising the DOC from biochars were investigated by attenuated total reflectance Fourier transform infrared spectroscopy. The addition of DOC did not change the biomineral structure or As(V) oxidation state. The presence of DOC, however, reduced by 25 % the sorption of As(V), with BC350 being responsible for the greatest reduction in As(V) sorption capacity. Structural modeling revealed As(V) predominantly formed binuclear bidentate surface complexes on BIOS. The presence of DOC did not change the binding mechanism of As(V) in BIOS, suggesting that the reduction of As(V) sorption to BIOS was due to site blocking. Our results bring insights into the fate of As(V) in surface waters and provide a basis for understanding the competitive sorption of As(V) in environments with biochar application.


Subject(s)
Arsenic , Iron , Humans , Oxides , Carbon , Arsenic/analysis , Charcoal/chemistry , X-Ray Absorption Spectroscopy , Adsorption
10.
PLoS Negl Trop Dis ; 17(1): e0011039, 2023 01.
Article in English | MEDLINE | ID: mdl-36719867

ABSTRACT

Canine leishmaniasis (CanL) is a severe public health threat. Infected animals mediate transmission of the Leishmania protozoan to humans via the sandfly's bite during a blood meal. CanL progression depends on the degree of suppression of the immune response, possibly associated with microRNAs (miR), which can modulate mRNA translation into proteins and (consequently) regulate cell function. Increased miR-148a in splenic leukocytes (SL) of dogs with CanL was observed in previous studies, and in silico analysis, identified possible pathways involved in immune response regulation that are affected by this miR. Therefore, we evaluated the involvement of miR-148a in the regulation of TNF-α, IL-6, IL-12, IL-1ß, iNOS, MHCII, CD80, CD3, T-bet, and GATA-3 transcription factors and their relationship with parasite load in SL of dogs with CanL. Splenic leukocytes obtained from healthy and diseased dogs were transfected with miR-148a mimic and inhibitor oligonucleotides. After 48 hours, expression levels of MHCII, CD80, iNOS, CD3, T-bet, and GATA-3 were evaluated by flow cytometry, and concentrations of TNF-α, IL-12, IL-6, and IL-1ß were measured in culture supernatants by capture enzyme-linked immunosorbent assays. Transfection of SL with miR-148a mimics decreased iNOS levels in cells and TNF-α, IL-6, and IL-12 in the supernatants of cultured SL from CanL dogs. Interestingly, transfection with miR-148a inhibitor decreased parasite load in SL cells. These results suggest a direct or not regulatory role of this miR in the immune response to Leishmania infantum infection. We conclude that miR-148a can modulate immune responses by regulating inflammatory cytokines during CanL. Our results contribute to understanding the complex host/parasite interaction in CanL and could assist the development of treatments.


Subject(s)
Dog Diseases , Leishmania infantum , Leishmaniasis, Visceral , Leishmaniasis , MicroRNAs , Animals , Dogs , Cytokines , Dog Diseases/parasitology , Interleukin-12/genetics , Interleukin-6 , Leishmania infantum/genetics , Leishmaniasis/veterinary , Leishmaniasis, Visceral/parasitology , MicroRNAs/genetics , Parasite Load , Tumor Necrosis Factor-alpha/genetics
11.
Sci Total Environ ; 864: 161009, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36549526

ABSTRACT

Mining is an important component of the Brazilian economy. However, it may also contribute to environmental problems such as the pollution of soils with zinc and other potentially toxic metals. Our objective was to evaluate changes in the chemical speciation and mobility of Zn in a soil amended with phosphate. Soil samples were collected from a deactivated mining area in the state of Minas Gerais, Brazil, and amended with NH4H2PO4 saturated with deionized water to 70 % of maximum water retention and incubated at 25 ± 2 °C in open containers for 60 days. The soil was chemically and mineralogically characterized, and sequential extraction, desorption kinetics, and speciation were carried out using synchrotron bulk-sample and micro-X-ray Absorption Near-Edge Structure (XANES/µ-XANES) spectroscopy at the Zn K-edge, and X-ray fluorescence microprobe analysis (µ-XRF). The combination of µ-XRF and µ-XANES techniques made it possible to identify Zn hotspots in the main species formed after phosphate remediation. The best fit combination for bulk XANES and µ-XANES was observed in Zn-montmorillonite, Zn-kerolite, Zn-ferrihydrite, and gahnite. In the course of phosphate treatment, gahnite, Zn layered double hydroxides (Zn-LDH), Zn3(PO4), and ZnO were identified by bulk XANES, while Zn-ferrihydrite, Zn-montmorillonite, and scholzite were identified by µ-XANES. Zinc in the phosphate-amended soil had the strongest partial correlations (r' > 0.05) with Ni, Co, Fe, Cr, Mn, Si, P, Cd, Pb, and Cd, while the unamended soil showed the strongest correlation with Cu, Pb, Fe, and Si. The application of NH4H2PO4 altered Zn speciation and favored an increase in Zn desorption. The most available Zn contents after phosphate amendment were correlated with the release of exchangeable Zn fractions, associated with carbonate and organic matter.

12.
Zootaxa ; 5323(2): 151-182, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-38220972

ABSTRACT

The Paraclius arcuatus species-group is reviewed and includes the following seven species: P. angusticauda Van Duzee, 1933, P. angustipennis Van Duzee, 1929, P. arcuatus (Loew, 1861), P. brooksi sp. nov., P. elongatus Van Duzee, 1930, P. pumilio Loew, 1872, and P. xibun sp. nov. Paraclius angustipennis, P. arcuatus and P. pumilio are redescribed based on photographs of types and additional specimens. Paraclius femoratus Aldrich, 1901 is synonymized with P. arcuatus, syn. nov. and Paraclius magnicornis Van Duzee, 1927 is regarded as a junior synonym of P. pumilio, syn. nov. An identification key, distribution maps and high-resolution photographs of species are provided. In addition, the systematic position of Paraclius is discussed.


Subject(s)
Diptera , Animals , Animal Distribution
13.
Zootaxa ; 5389(2): 151-172, 2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38221032

ABSTRACT

A new dolichopodid genus (Diptera, Dolichopodidae), Rafaelomyia Soares, Capellari & Ramos-Pastrana gen. nov., is described and comprises the following five new species from Northern South America: Rafaelomyia exu Soares & Capellari sp. nov. (Cusco, Peru), R. inpa Soares, Capellari & Ramos-Pastrana sp. nov. (Cusco, Peru), R. singularis Soares & Capellari sp. nov. (Cusco, Peru), R. uniamazonia Ramos-Pastrana & Soares sp. nov. (Huila, Colombia), and R. xavieri Soares & Capellari sp. nov. (Cusco, Peru). The new genus is tentatively placed in the subfamily Sympycninae based on a suite of characters traditionally associated with the subfamily: head ovate on anterior view (antenna on top of head), wing with bosse alaire, vein M unbranched into M1 and M2, tibia I with anterodorsal row of setae, male abdomen not pedunculated, with setose tergite 6 and male hypopygium relatively small, despite the lack of anterior preapical setae on femur II and/or III and the presence of a conspicuous flattened posterior slope of mesonotum. The systematic position of the new genus is discussed and an identification key to males is provided.


Subject(s)
Diptera , Male , Animals , Wings, Animal
14.
Biota Neotrop. (Online, Ed. ingl.) ; 23(3): e20231492, 2023. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1505828

ABSTRACT

Abstract We recorded for the first time the lesser dung fly Maculantrops hirtipes (Macquart, 1844) from Brazil, state of Rio Grande do Sul. Twenty-five specimens were reared from the dung of Myocastor coypus (Molina, 1782), this is the first record of the feeding substrate for the genus Maculantrops and the second only for the Archiborborinae. In addition, we describe the puparium, provide an updated distribution map and additional photographs of the species.


Resumo Registramos pela primeira vez a mosca-do-esterco Maculantrops hirtipes (Macquart, 1844) no Brasil, no estado do Rio Grande do Sul. Vinte e cinco espécimes foram obtidos em amostras fecais de Myocastor coypus (Molina, 1782). Este é o primeiro registro do substrato alimentar para o gênero Maculantrops e o segundo apenas para subfamília Archiborborinae. Além disso, descrevemos o pupário, fornecemos um mapa de distribuição atualizado e fotografias adicionais da espécie.

15.
Zootaxa ; 5150(4): 516-528, 2022 Jun 09.
Article in English | MEDLINE | ID: mdl-36095649

ABSTRACT

Pseudoscelolabes Collin, 1933, an endemic New Zealand genus, is revised, including the description of a new species, P. lesagei Sinclair Barros sp. nov. The male and female terminalia of the genus are described and illustrated for the first time. An identification key to the two included species and a map with distribution records are provided. The relationships of the genus within Ocydromiinae are discussed.


Subject(s)
Diptera , Animal Distribution , Animals , Female , Male , New Zealand
16.
Zootaxa ; 5182(2): 175-182, 2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36095692

ABSTRACT

Larvae of Copestylum tigrinum Ricarte Hancock in Ricarte et al. 2015 were reared from fallen fruits of Casearia combaymensis Tul. (Salicaceae) collected in the Brazilian Amazon (Amazonas, Brazil). This is the first record of this species in mainland South America and Brazil, and the first record of a fruit of Salicaceae as a food substrate for the larvae of C. tigrinum. The female and its genitalia are described for the first time, the puparium is redescribed and some aspects of the biology of Copestylum are discussed.


Subject(s)
Diptera , Animals , Fruit , Genitalia , Larva
17.
Neotrop Entomol ; 51(5): 742-751, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35980562

ABSTRACT

This study presents some updates on the Brazilian hangingflies species of the genera Issikiella Byers, Nannobittacus Esben-Petersen, and Pazius Navás (Insecta: Mecoptera: Bittacidae). All species with records from Brazil were included in the study, resulting in some new state records and a new synonym (Pazius cinctipes Byers and Florez under P. ornaticaudus Penny). Biological notes on P. ornaticaudus and distribution maps for all species were also provided.


Subject(s)
Holometabola , Animals , Brazil , Insecta
18.
J Environ Manage ; 321: 116017, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36027729

ABSTRACT

Nano zero-valent iron (nZVI) is one of the most studied nanomaterials for environmental remediation during the past 20 years. However, few studies have focused on nZVI combination with other materials (e.g., biochar) for enhancement of soil remediation. In this study, pristine nZVI and a composite of wood sawdust biochar (BC) and nZVI (nZVI-BC) were added to a highly contaminated soil to compare their efficacy in immobilizing available arsenic (As = 28.6 mg kg-1), zinc (Zn = 1707 mg kg-1), and lead (Pb = 6759 mg kg-1). Sediment quality guidelines were used to evaluate the extent of soil contamination and ascertain its source. The mineralogy of soil and slags were assessed by X-ray Diffractometry Spectroscopy (XRD), and the geochemical fractions of Pb, Zn, and As were obtained by chemical sequential extractions. The average Pollution Load Index (PLI) was 10.66, indicating elevated multi-elemental contamination. Contamination Factor (CF) values for As, Zn, Pb, cadmium (Cd), and copper (Cu) were all higher than 6 which implies extreme contamination. Secondary minerals frequently found in Pb/Zn smelter sites, such as cerussite and anglesite, were detected in the slags through XRD. Pb and Zn were mainly bound to carbonates and residual fractions in soil and presented a high risk considering the sediment quality guidelines, sequential extraction results, and XRD analysis. The treatment with nZVI-BC was more effective than pristine nZVI on concurrently decreasing 97% of available As, 84% of Pb and 81% of Zn compared to control. The application of nZVI-BC is a promising green and sustainable remediation technique for soils contaminated with potentially toxic elements of distinct chemical behavior.


Subject(s)
Environmental Restoration and Remediation , Soil Pollutants , Charcoal/chemistry , Iron/chemistry , Lead/analysis , Soil/chemistry , Soil Pollutants/analysis , Zinc/chemistry
19.
Zootaxa ; 5120(3): 391-401, 2022 Mar 28.
Article in English | MEDLINE | ID: mdl-35391161

ABSTRACT

A new species of the New World genus Trivialia Malloch from Peru is described and illustrated, along with discussion of unusual head morphology in Lauxaniidae. This new species represents an odd case where only a single known species in an otherwise non-dimorphic genus displays extreme sexual dimorphism.


Subject(s)
Diptera , Animals , Peru , Sex Characteristics
20.
Arq. neuropsiquiatr ; 80(4): 344-352, Apr. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1374468

ABSTRACT

ABSTRACT Background: Transcranial Doppler has been tested in the evaluation of cerebral hemodynamics as a non-invasive assessment of intracranial pressure (ICP), but there is controversy in the literature about its actual benefit and usefulness in this situation. Objective: To investigate cerebral blood flow assessed by Doppler technique and correlate with the variations of the ICP in the acute phase of intracranial hypertension in an animal model. Methods: An experimental animal model of intracranial hypertension was used. The experiment consisted of two groups of animals in which intracranial balloons were implanted and inflated with 4 mL (A) and 7 mL (B) for controlled simulation of different volumes of hematoma. The values of ICP and Doppler parameters (systolic [FVs], diastolic [FVd], and mean [FVm] cerebral blood flow velocities and pulsatility index [PI]) were collected during the entire procedure (before and during hematoma simulations and venous hypertonic saline infusion intervention). Comparisons between Doppler parameters and ICP monitoring were performed. Results: Twenty pigs were studied, 10 in group A and 10 in group B. A significant correlation between PI and ICP was obtained, especially shortly after abrupt elevation of ICP. There was no correlation between ICP and FVs, FVd or FVm separately. There was also no significant change in ICP after intravenous infusion of hypertonic saline solution. Conclusions: These results demonstrate the potential of PI as a parameter for the evaluation of patients with suspected ICP elevation.


RESUMO Antecedentes: O Doppler transcraniano (DTC) é uma técnica não invasiva para a avaliação da hemodinâmica cerebral, porém existem controvérsias na literatura sobre sua aplicabilidade preditiva em situações de elevada pressão intracraniana (PIC). Objetivo: Investigar o fluxo sanguíneo cerebral pelo DTC e correlacioná-lo com as variações da PIC na fase aguda da hipertensão intracraniana em modelo animal. Métodos: Dois grupos de animais (suínos) foram submetidos a hipertensão intracraniana secundária à indução de diferentes volumes de hematoma, por meio da insuflação de balão intracraniano controlado com 4 e 7 mL de solução salina fisiológica (grupos A e B, respectivamente). Em seguida, administrou-se infusão venosa de solução salina hipertônica (SSH 3%). Foram coletados os valores dos parâmetros de PIC e DTC (velocidade sistólica [FVs], diastólica [FVd] e média [FVm] do fluxo sanguíneo cerebral), bem como o índice de pulsatilidade (IP). Comparações entre os parâmetros do DTC e o monitoramento da PIC foram realizadas. Resultados: Vinte porcos foram estudados, dez no grupo A e dez no grupo B. Correlação significativa entre IP e PIC foi obtida, principalmente logo após a elevação abrupta da PIC. Não houve correlação entre PIC e FVs, FVd ou FVm separadamente. Também não houve alteração significativa na PIC após a infusão de SSH. Conclusões: Esses resultados demonstram o potencial do IP como um bom parâmetro para a avaliação de pacientes com suspeita de elevação da PIC.

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