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1.
Med Hypotheses ; 167: 110943, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36105250

RESUMO

SARS-CoV-2 infection intrigued medicine with diverse outcomes ranging from asymptomatic to severe acute respiratory syndrome (SARS) and death. After more than two years of pandemic, reports of reinfection concern researchers and physicists. Here, we will discuss potential mechanisms that can explain reinfections, including the aggravated ones. The major topics of this hypothesis paper are the disbalance between interferon and antibodies responses, HLA heterogeneity among the affected population, and increased proportion of cytotoxic CD4+ T cells polarization in relation to T follicular cells (Tfh) subtypes. These features affect antibody levels and hamper the humoral immunity necessary to prevent or minimize the viral burden in the case of reinfections.

3.
Cell Biochem Biophys ; 80(1): 97-113, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34800278

RESUMO

HO-1 is the inducible form of the enzyme heme-oxygenase. HO-1 catalyzes heme breakdown, reducing the levels of this important oxidant molecule and generating antioxidant, anti-inflammatory, and anti-apoptotic byproducts. Thus, HO-1 has been described as an important stress response mechanism during both physiologic and pathological processes. Interestingly, some findings are demonstrating that uncontrolled levels of HO-1 byproducts can be associated with cell death and tissue destruction as well. Furthermore, HO-1 can be located in the nucleus, influencing gene transcription, cellular proliferation, and DNA repair. Here, we will discuss several studies that approach HO-1 effects as a protective or detrimental mechanism in different pathological conditions. In this sense, as the major organs of vertebrates will deal specifically with distinct types of stresses, we discuss the HO-1 role in each of them, exposing the contradictions associated with HO-1 expression after different insults and circumstances.


Assuntos
Heme Oxigenase-1 , Oxidantes , Animais , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Vertebrados/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-35010675

RESUMO

This work aimed to apply the ARIMA model to predict the under-reporting of new Hansen's disease cases during the COVID-19 pandemic in Palmas, Tocantins, Brazil. This is an ecological time series study of Hansen's disease indicators in the city of Palmas between 2001 and 2020 using the autoregressive integrated moving averages method. Data from the Notifiable Injuries Information System and population estimates from the Brazilian Institute of Geography and Statistics were collected. A total of 7035 new reported cases of Hansen's disease were analyzed. The ARIMA model (4,0,3) presented the lowest values for the two tested information criteria and was the one that best fit the data, as AIC = 431.30 and BIC = 462.28, using a statistical significance level of 0.05 and showing the differences between the predicted values and those recorded in the notifications, indicating a large number of under-reporting of Hansen's disease new cases during the period from April to December 2020. The ARIMA model reported that 177% of new cases of Hansen's disease were not reported in Palmas during the period of the COVID-19 pandemic in 2020. This study shows the need for the municipal control program to undertake immediate actions in terms of actively searching for cases and reducing their hidden prevalence.


Assuntos
COVID-19 , Hanseníase , Brasil/epidemiologia , Humanos , Hanseníase/epidemiologia , Modelos Estatísticos , Pandemias , SARS-CoV-2
5.
Microsc Res Tech ; 83(3): 287-296, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31729116

RESUMO

Micromorphological studies were carried out using multiple microscopic techniques on the leaves and stem bark of Byrsonima sericea DC. (Malpighiaceae), a species popularly known as "murici" and used medicinally, in order to identify both qualitative and quantitative features of leaf and stem anatomy and histochemistry as differential parameters to support both the quality control of its ethnodrugs and the taxonomy of the genus. The study was conducted using traditional techniques of plant anatomy, histochemical tests, and the stomatal index (SI). Byrsonima sericea has hypostomatic leaves, anomocytic stomata, and its epidermal walls are anticlinal and straight on the adaxial and curved on the abaxial faces. T-shaped trichomes were observed mainly on the abaxial surface. The leaf epidermis showed waxes syntopism on both surfaces, with the occurrence of different crystalloid forms on a single phylloplane. The mesophyll is dorsiventral, with 3-4 collateral vascular bundles. Phenolic compounds, starch, and proteins were identified in the petiole and stem. The SI was 14.5 ± 0.53% (p < .05), but did not showed significant variations. A set of characters were found to be distinctive for the studied species, however, constituting parameters that could be used to separate B. sericea from other species of the genus.


Assuntos
Malpighiaceae/anatomia & histologia , Folhas de Planta/citologia , Folhas de Planta/ultraestrutura , Caules de Planta/citologia , Caules de Planta/ultraestrutura , Histocitoquímica , Microscopia , Microscopia Eletrônica de Varredura , Epiderme Vegetal/ultraestrutura , Estômatos de Plantas/ultraestrutura
6.
Rev. bras. farmacogn ; 28(4): 383-392, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958893

RESUMO

Abstract Bauhinia L. and Schnella (Raddi.) Wund. are popularly known in Brazil as "mororó". The leaves and stem bark are used in folk medicine for various purposes, especially against diabetes. Morphoanatomical studies of the leaves of Bauhinia cheilantha (Bong.) Steud., B. pentandra (Bong.) Steud., B. ungulata L. and Schnella outimouta (Aublet) Wund., tribe Cercidae, subtribe Bauhiniinae (Benth.) Walp., were carried out as subsidies to the quality control of their etnodrugs and their derivatives, as well as an additional support to their taxonomy. The morphological and anatomical studies employed traditional techniques of stereo- and light microscopy. All species showed bifoliate leaves, a dorsiventral mesophyll, epidermis with a papillose abaxial surface, anomocytic stomata at the level of the epidermis, and tector trichomes. Schnella outimouta showed leaf characters distinctive from the three species of Bauhinia: indument puberulous on the abaxial surface, leaves hypostomatic, midrib with two collateral bundles, and a cylindrical petiole. The species of Bauhinia have a sericeous-pubescent indument, amphistomatic leaves with boat-shaped glands, midrib with a single bundle, and a canaliculate petiole with lateral projections. Our results provide leaf morphological and anatomical parameters, useful to distinguish the four species studied, which support the quality control of its ethnodrugs.

7.
Toxicon ; 65: 5-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23333648

RESUMO

The invasive fire ant Solenopsis invicta is medically important because its venom is highly potent. However, almost nothing is known about fire ant venom proteins because obtaining even milligram-amounts of these proteins has been prohibitively challenging. We present a simple and fast method of obtaining whole venom compounds from large quantities of fire ants. For this, we separate the ants are from the nest soil, immerse them in dual-phase mixture of apolar organic solvent and water, and evaporate each solvent phase in separate. The remaining extract from the aqueous phase is largely made up of ant venom proteins. We confirmed this by using 2D gel electrophoresis while also demonstrating that our new approach yields the same proteins obtained by other authors using less efficient traditional methods.


Assuntos
Venenos de Formiga/isolamento & purificação , Formigas/química , Fracionamento Químico/métodos , Animais , Eletroforese em Gel Bidimensional
8.
Rev. bras. farmacogn ; 21(4): 568-574, jul.-ago. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-596223

RESUMO

In this work, a morpho-anatomical study of the leaves, stems and roots of Solanum torvum Sw. was performed with the objective of providing a macroscopical and microscopical morphodiagnosis for its characterization. The species is popularly called "jurubeba-branca" in the Northeastern Brazil and is used in folk medicine to treat liver diseases, tuberculosis, and as antianemic. Anatomical studies were done by paradermic sections of the leaf blade (adaxial and abaxial surfaces), and cross sections of leaves (blade and petiole), stems and roots. The sections were clarified and stained with safranin and/ or astrablue, observed and photographed on light microscope. Histochemical tests were carried out in cross sections of leaves, stems and roots and assayed for specific reagents. The leaves are chartaceous, ovate to elliptic, with lobed margins, oblique at the base. The leaf is amphistomatic with anisocytic and anomocytic stomata simultaneously, and the epidermal cells, in face view, have anticlinal walls sinuate on the upper surface and wavy on the lower surface. The mesophyll is dorsiventral; the midrib has a central bicollateral vascular bundle; and the petiole has three or fourone. The stem shows external phloem, xylem, internal phloem and a parenchymatic pith. The root is axial and striate longitudinally and the secondary xylem is a massive cylinder. The macroscopical and microscopical vegetative characters constitute a set of diagnostic parameters to the studied species.

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