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1.
Front Microbiol ; 15: 1426166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38989019

RESUMEN

Phosphorus (P) is a critical nutrient for plant growth, yet its uptake is often hindered by soil factors like clay minerals and metal oxides such as aluminum (Al), iron (Fe), and calcium (Ca), which bind P and limit its availability. Phosphate-solubilizing bacteria (PSB) have the unique ability to convert insoluble P into a soluble form, thereby fostering plant growth. This study aimed to assess the efficacy of inoculation of Bacillus megaterium B119 (rhizospheric) and B. subtilis B2084 (endophytic) via seed treatment in enhancing maize yield, grain P content, and enzyme activities across two distinct soil types in field conditions. Additionally, we investigated various mechanisms contributing to plant growth promotion, compatibility with commercial inoculants, and the maize root adhesion profile of these strains. During five crop seasons in two experimental areas in Brazil, Sete Lagoas-MG and Santo Antônio de Goiás-GO, single inoculations with either B119 or B2084 were implemented in three seasons, while a co-inoculation with both strains was applied in two seasons. All treatments received P fertilizer according to plot recommendations, except for control. Both the Bacillus strains exhibited plant growth-promoting properties relevant to P dynamics, including phosphate solubilization and mineralization, production of indole-3-acetic acid (IAA)-like molecules, siderophores, exopolysaccharides (EPS), biofilms, and phosphatases, with no antagonism observed with Azospirillum and Bradyrizhobium. Strain B2084 displayed superior maize root adhesion compared to B119. In field trials, single inoculations with either B119 or B2084 resulted in increased maize grain yield, with relative average productivities of 22 and 16% in Sete Lagoas and 6 and 3% in Santo Antônio de Goiás, respectively. Co-inoculation proved more effective, with an average yield increase of 24% in Sete Lagoas and 11% in Santo Antônio de Goiás compared to the non-inoculated control. Across all seasons, accumulated grain P content correlated with yield, and soil P availability in the rhizosphere increased after co-inoculation in Santo Antônio de Goiás. These findings complement previous research efforts and have led to the validation and registration of the first Brazilian inoculant formulated with Bacillus strains for maize, effectively enhancing and P grain content.

2.
Vox Sang ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970294

RESUMEN

BACKGROUND AND OBJECTIVES: In Brazil, urban arboviruses, such as dengue virus (DENV), Zika virus (ZIKV) and chikungunya virus (CHIKV), constitute a major public health problem, and due to their endemicity and asymptomatic cases, they pose a potential threat to blood donations. Rio de Janeiro (RJ), Brazil, has been impacted by extensive DENV epidemics over the last 30 years and, after 2015, by CHIKV and ZIKV. MATERIALS AND METHODS: Urban arboviruses DENV, ZIKV and CHIKV were investigated in blood donations (n = 778) at the State Institute of Hematology, HEMORIO (RJ) from 2019 to 2022 by serological and molecular methods. RESULTS: An overall arbovirus exposure was observed in 26.1% of the blood donations. Anti-DENV IgM was detected in 4.0% of samples and two donations were DENV NS1 positive. Positive anti-CHIKV IgM was observed in 4.7% of the donations. Co-detection of anti-CHIKV IgM and anti-DENV IgM was observed in 1.0% of donors, and CHIKV prevalence was 21.3%. All blood donations tested were negative for the DENV, ZIKV and CHIKV RNA. CONCLUSION: IgM seroprevalence to the arboviruses analyzed here is an indicator of recent infection in asymptomatic donors, showing that the population of blood donors can be a vehicle for new infections, especially during epidemic periods.

3.
One Health Outlook ; 6(1): 12, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946009

RESUMEN

Oropouche and Mayaro viruses are enzootic arboviruses of public health concern throughout Latin America. Recent outbreaks of OROV in northern region and sporadic autochthonous cases in western region of Brazil, suggest a silent circulation of these neglected viruses. Aiming to investigate the exposure of different species of domestic animals to MAYV and OROV in urban and peri-urban areas of West-Central Brazil, we performed a cross-sectional serosurvey by plaque reduction neutralization test (PRNT). Our findings included neutralizing antibodies for both arboviruses in cattle, dogs and horses, suggesting eventual role of domestic animals in enzootic arbovirus surveillance in Brazil.

4.
Pathogens ; 13(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38921767

RESUMEN

Oropouche orthobunyavirus (OROV) is an arbovirus transmitted by midges that has been involved in outbreaks throughout Central and South America. In Brazil, human cases have been historically concentrated in the northern region of the country. Oropouche fever in humans range from mild clinical signs to rare neurological events, and is considered a neglected tropical disease in Brazil. Due to the clinical similarities to other arboviruses, such as chikungunya and dengue viruses, OROV infections are likely to be underreported. Chikungunya virus (CHIKV) cases in Brazil were first recognized in 2014 in the states of Amapá and Bahia in the north and northeast regions, respectively. Both OROV and CHIKV cause nonspecific symptoms, making clinical diagnosis difficult in a scenario of arbovirus cocirculation. Aiming to investigate OROV transmission during the CHIKV introduction in the state of Amapá located in the Brazilian Amazon, we conducted a retrospective molecular (RT-qPCR) and serological investigation in febrile cases (N = 166) collected between August 2014 and May 2015. All acute serum samples were negative for OROV RNA using RT-qPCR. However, neutralizing antibodies for OROV were detected using a plaque reduction neutralization test (PRNT90) in 10.24% (17/166) of the patients, with neutralizing antibody titers ranging from 20 to ≥640, suggesting the previous exposure of patients to OROV. Regarding CHIKV, recent exposure was confirmed by the detection of CHIKV RNA in 20.25% (33/163) of the patients and by the detection of anti-CHIKV IgM in 28.57% (44/154) of the patients. The additional detection of anti-CHIKV IgG in 12.58% (19/151) of the febrile patients suggests that some individuals had been previously exposed to CHIKV. Whether the OROV exposure reported here occurred prior or during the CHIKV circulation in Amapá, is unknown, but because those arboviral infections share similar clinical signs and symptoms, a silent circulation of enzootic arboviruses during the introduction of exotic arboviruses may occur, and highlights the importance of syndromic cases' surveillance to arboviruses in Brazil.

5.
Environ Toxicol ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712533

RESUMEN

Cadmium (Cd) is a heavy metal that acts as endocrine disrupting chemical (EDC). Few studies have investigated the effects of Cd exposure on metabolic dysfunctions, such as type 1 and 2 diabetes mellitus (T1DM and T2DM). Thus, we assessed whether subacute Cd exposure at occupational levels causes abnormalities in white adipose tissue (WAT), liver, pancreas, and skeletal muscle. We administered cadmium chloride (CdCl2) (100 ppm in drinking water for 30 days) to female rats and evaluated Cd levels in serum and metabolic organs, morphophysiology, inflammation, oxidative stress, fibrosis, and gene expression. High Cd levels were found in serum, WAT, liver, pancreas, and skeletal muscle. Cd-exposed rats showed low adiposity, dyslipidemia, insulin resistance, systemic inflammation, and oxidative stress compared to controls. Cd exposure reduced adipocyte size, hyperleptinemia, increased cholesterol levels, inflammation, apoptosis and fibrosis in WAT. Cd-exposed rats had increased liver cholesterol levels, insulin receptor beta (IRß) and peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC1α) expression, karyomegaly, inflammation, and fibrosis. Cd exposure reduced insulin levels and pancreatic islet size and increased inflammation and fibrosis. Cd exposure reduced skeletal muscle fiber diameter and increased IR expression and inflammation. Finally, strong positive correlations were observed between serum, tissue Cd levels, abnormal morphology, tissue inflammation and fibrosis. Thus, these data suggest that subacute Cd exposure impairs WAT, liver, pancreas and skeletal muscle function, leading to T1DM and T2DM features and other complications in female rats.

6.
Viruses ; 16(3)2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38543735

RESUMEN

Uncaria tomentosa (UT) is a medicinal plant popularly known as cat's claw belonging to the Rubiaceae family that has been reported to display antiviral and anti-inflammatory activities. The chikungunya virus (CHIKV) outbreaks constitute a Brazilian public health concern. CHIKV infection develops an abrupt onset of fever, usually accompanied by a skin rash, besides incapacitating polyarthralgia. There is no vaccine available or treatment for CHIKV infection. The present study evaluates the hydroalcoholic extract of UT bark as a potential antiviral against CHIKV. The in vitro antiviral activity of the UT extract against the Brazilian CHIKV strain was assessed using quantitative reverse transcription polymerase chain reaction, flow cytometry, and plaque assay. Results obtained demonstrated that UT inhibits CHIKV infection in a dose-dependent manner. At the non-cytotoxic concentration of 100 µg/mL, UT exhibited antiviral activity above 90% as determined by plaque reduction assay, and it reduced the viral cytopathic effect. Similarly, a significant virucidal effect of 100 µg/mL UT was observed after 24 and 48 h post-infection. This is the first report on the antiviral activity of UT against CHIKV infection, and the data presented here suggests UT as a potential antiviral to treat CHIKV infection.


Asunto(s)
Uña de Gato , Fiebre Chikungunya , Virus Chikungunya , Plantas Medicinales , Extractos Vegetales/farmacología , Antivirales/farmacología , Fiebre Chikungunya/tratamiento farmacológico
7.
Mol Cell Endocrinol ; 586: 112203, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38490633

RESUMEN

Microcystin (MC) is most common cyanobacterial toxin. Few studies have evaluated the MC effects on the hypothalamic-pituitary-gonadal (HPG) axis and metabolic function. In this study, we assessed whether MC exposure results in HPG axis and metabolic changes. Female rats were exposed to a single dose of MC at environmentally relevant levels (5, 20 and 40 µg/kg). After 24 h, we evaluated reproductive and metabolic parameters for 15 days. MC reduced the hypothalamic GnRH protein expression, increased the pituitary protein expression of GnRHr and IL-6. MC reduced LH levels and increased FSH levels. MC reduced the primary follicles, increased the corpora lutea, elevated levels of anti-Müllerian hormone (AMH) and progesterone, and decreased estrogen levels. MC increased ovarian VEGFr, LHr, AMH, ED1, IL-6 and Gp91-phox protein expression. MC increased uterine area and reduced endometrial gland number. A blunted estrogen-negative feedback was observed in MC rats after ovariectomy, with no changes in LH levels compared to intact MC rats. Therefore, these data suggest that a MC leads to abnormal HPG axis function in female rats.


Asunto(s)
Eje Hipotálamico-Pituitario-Gonadal , Microcistinas , Ratas , Femenino , Animales , Microcistinas/toxicidad , Interleucina-6/metabolismo , Ovario/metabolismo , Estrógenos , Hormona Liberadora de Gonadotropina/metabolismo
8.
Microorganisms ; 12(3)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38543645

RESUMEN

Following the first report of zika virus in March 2015, Brazil experienced its largest sylvatic yellow fever outbreak between 2016 and 2019. This study aimed to investigate the circulation of yellow fever virus (YFV) in non-human primates (NHPs) and mosquitoes collected in urban parks and other metropolitan areas of midwest Brazil between 2017 and 2018. Whole blood samples from 80 NHPs, including 48 black-tailed marmosets (Mico melanurus) and 2332 mosquitoes from six different genera, were collected in the states of Mato Grosso (MT) and Mato Grosso do Sul (MS) and then tested for YFV by RT-qPCR. Additionally, 23 plasma samples of NHPs were tested for neutralizing antibodies for YFV by a plaque reduction neutralization test (PRNT). No YFV RNA or neutralizing antibodies for YFV were detected in NHPs and mosquitoes from MT and MS. The continuous monitoring of YFV circulation in different species of NHPs and vectors in urban areas is instrumental to quickly assess potentially unknown maintenance cycles of yellow fever at the human-animal interface in Brazil.

9.
Braz J Microbiol ; 55(1): 737-748, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38008804

RESUMEN

Bacterial inoculants have been used in agriculture to improve plant performance. However, laboratory and field requirements must be completed before a candidate can be employed as an inoculant. Therefore, this study aimed to evaluate the parameters for inoculant formulation and the potential of Bacillus subtilis (B70) and B. pumilus (B32) to improve phosphorus availability in maize (Zea mays L.) crops. In vitro experiments assessed the bacterial ability to solubilize and mineralize phosphate, their adherence to roots, and shelf life in cassava starch (CS), carboxymethyl cellulose (CMC), peat, and activated charcoal (AC) stored at 4 °C and room temperature for 6 months. A field experiment evaluated the effectiveness of strains to increase the P availability to plants growing with rock phosphate (RP) and a mixture of RP and triple superphosphate (TS) and their contribution to improving maize yield and P accumulation in grains. The B70 was outstanding in solubilizing RP and phytate mineralization and more stable in carriers and storage conditions than B32. However, root adherence was more noticeable in B32. Among carriers, AC was the most effective for preserving viable cell counts, closely similar to those of the initial inoculum of both strains. Maize productivity using the mixture RPTS was similar for B70 and B32. The best combination was B70 with RP, which improved the maize yield (6532 kg ha-1) and P accumulation in grains (15.95 kg ha-1). Our results indicated that the inoculant formulation with AC carrier and B70 is a feasible strategy for improving phosphorus mobilization in the soil and maize productivity.


Asunto(s)
Bacillus , Fosfatos , Fosfatos/metabolismo , Bacillus/metabolismo , Raíces de Plantas/microbiología , Fósforo/metabolismo , Bacillus subtilis/metabolismo , Suelo , Zea mays/microbiología
10.
Cytokine ; 171: 156350, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37672863

RESUMEN

Immunological and cytotoxic mediators are induced in natural infection and are essential for the effectiveness of vaccination. Vaccination is useful to prevent the spread of SARS-CoV-2 and limit the morbidity/mortality of COVID-19. ChAdOx1 nCoV-19 is one of the most widespread vaccines in the world. We compared the detection of anti-S1 SARS-CoV2 IgG and the profile of inflammatory and cytotoxic responses of patients who developed different clinical outcomes of COVID-19 with individuals previously exposed or not to the virus received the first and booster doses of ChAdOx1 nCoV-19. Plasma from 35 patients with COVID-19 and 11 vaccinated were evaluated by multiplex assay. Here, no vaccinated subjects had serious adverse effects. Those vaccinated with a booster dose had higher anti-S1 IgG than mild/moderate and recovered patients. Critically ill and deceased patients had IgG levels like those immunized. By univariate analysis, IL-2, IL-17, and perforin do not differentiate between patients and vaccinated individuals. Granzyme A increased at dose 1, while patients had their levels reduced. High levels of granulysin, sFas, and IL-6 were detected in the deaths, but after vaccination, all were declined. The multivariate analysis supports the role of IL-6 and granulysin as associated and non-confounding variables related to the worst clinical outcome of COVID-19, but not sFas. Our data confirm the ability of the ChAdOx1 vaccine to produce specific antibody levels up to booster time. Furthermore, our data suggest that the vaccine can regulate both the hyper-production and the kinetics of the production of inflammatory and cytotoxic mediators involved in the cytokine storm, such as granulysin and IL-6.


Asunto(s)
Antineoplásicos , COVID-19 , Vacunas , Humanos , ChAdOx1 nCoV-19 , Interleucina-6 , ARN Viral , SARS-CoV-2 , Inmunoglobulina G , Anticuerpos Antivirales
11.
Sci Total Environ ; 903: 166125, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37572909

RESUMEN

Most of the soil quality assessment protocols are focused on crop production and conservation management, while studies on vital soil functions, such as water recharge potential, should be incorporated into the monitoring of impacts on environmental quality. Our objective was to evaluate, through the Nexus approach, how dynamic (land use and management) and inherent (soil type) factors impact soil physical properties and processes that drive water recharge potential, biomass production, and water erosion in the Cantareira System, Brazil. The assessment considered three soils (Typic Hapludult, Typic Dystrudept, and Typic Usthortent) and four land uses (native forest, rotational grazing, extensive grazing, and eucalyptus), which constitute the main soils and land uses in the Cantareira System region. Representative soil samples were collected at 0-5 and 30-35 cm depth and analyzed for several soil physical quality indicators, which were used to calculate a Soil Physical Quality Index based on soil functions. Converting the native forest to eucalyptus and pasture reduced the overall soil physical quality and water recharge potential. The groundwater recharge potential function in the topsoil has the highest score of 0.72 for Typic Dystrudept in native forest contrasting with 0.16 for extensive pasture. Typic Dystrudept obtained the highest value of the SPQI value (0-5 cm: 0.85; 30-35 cm: 0.90) for native forests when compared to Typic Hapludult (0-5 cm: 0.76; 30-35 cm: 0.57) and Typic Usthortent (0-5 cm: 0.75; 30-35 cm: 0.72). Our findings sustain that land use effects on soil functions depends on soil type. Inclusion of soil type into the Nexus approach increases the understanding of natural resources and derived benefits of water, energy and food in the Cantareira System.

12.
Reprod Toxicol ; 120: 108441, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37473929

RESUMEN

The ovaries play critical roles in regulating oocyte maturation and sex steroid hormone production and thus are critical for female reproduction. Ovarian function relies on hormone receptors and signaling pathways, making the ovaries potential targets for environmental factors, such as microcystins (MCs). MCs are a diverse group of cyanobacterial toxins generally found in eutrophic water or algal blooms. Here, we review relevant research on the associations between MC exposure and ovarian dysfunction, including their effects on ovarian morphology, folliculogenesis, steroid production, oxidative stress, endoplasmic reticulum stress, apoptosis, autophagy, and fertility. This review covers the most recent in vitro and in vivo studies in mammals. We also discuss important gaps in the literature. Overall, current evidence indicates that MC exposure causes impairments in ovarian function, but further studies are needed to elucidate the mechanisms through which MCs affect ovarian function and other female endocrine functions.


Asunto(s)
Microcistinas , Ovario , Animales , Femenino , Microcistinas/toxicidad , Toxinas Marinas , Mamíferos
13.
Adv Rheumatol ; 63(1): 35, 2023 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-37496093

RESUMEN

OBJECTIVE: Takayasu arteritis (TAK) is a rare chronic granulomatous vasculitis that affects large vessels and usually begins in women of childbearing age, so it is not uncommon for pregnancies to occur in these patients. However, there is limited information about these pregnancies, with reports of adverse maternal and obstetric outcomes. The objective of this study is to evaluate adverse maternal, fetal and neonatal events in pregnant patients with TA. METHODS: This is a cross-sectional study with retrospective data collection. We reviewed 22 pregnancies in 18 patients with TAK, according to the American College of Rheumatology criteria, that were followed up in a high-risk prenatal clinic specialized in systemic autoimmune diseases and thrombophilia (PrAT) at Hospital Universitário Pedro Ernesto, from 1998 to 2021. RESULTS: In twenty-two pregnancies, the mean age of patients was 28.09 years and the mean duration disease was 10.9 years. Of the 18 patients with TAK studied, only one had the diagnosis during pregnancy and had active disease. All other patients had a previous diagnosis of TAK and only 3 had disease activity during pregnancy. Twelve patients (66.6%) had previous systemic arterial hypertension and eleven (61.1%) had renal involvement. Among maternal complications, eight patients (36.3%) developed preeclampsia and six (27.2%) had uncontrolled blood pressure without proteinuria, while 10 (45%) had puerperal complications. Four (18.1%) births were premature, all due to severe preeclampsia and eight newborns (34.7%) were small for gestational age. When all maternal and fetal/neonatal outcomes included in this study were considered, only 6 (27.2%) pregnancies were uneventful. CONCLUSION: Although there were no maternal deaths or pregnancy losses in this study, the number of adverse events was considerably high. Hypertensive disorders and small for gestational age newborns were more common than general population, while the number of patients with active disease was low. These findings suggest that pregnancies in patients with TAK still have several complications and a high-risk prenatal care and delivery are necessary for these patients.


Asunto(s)
Hipertensión , Preeclampsia , Complicaciones Cardiovasculares del Embarazo , Arteritis de Takayasu , Embarazo , Humanos , Femenino , Recién Nacido , Adulto , Resultado del Embarazo/epidemiología , Preeclampsia/epidemiología , Preeclampsia/etiología , Mujeres Embarazadas , Estudios Retrospectivos , Arteritis de Takayasu/diagnóstico , Brasil/epidemiología , Estudios Transversales , Complicaciones Cardiovasculares del Embarazo/epidemiología , Complicaciones Cardiovasculares del Embarazo/etiología
14.
BMC Infect Dis ; 23(1): 327, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37189054

RESUMEN

BACKGROUND: Identification of pleural effusion (PE) in dengue infection is an objective measure of plasma leakage and may predict disease progression. However, no studies have systematically assessed the frequency of PE in patients with dengue, and whether this differs across age and imaging modality. METHODS: We searched Pubmed, Embase Web of Science and Lilacs (period 1900-2021) for studies reporting on PE in dengue patients (hospitalized and outpatient). We defined PE as fluid in the thoracic cavity detected by any imaging test. The study was registered in PROSPERO (CRD42021228862). Complicated dengue was defined as hemorrhagic fever, dengue shock syndrome or severe dengue. RESULTS: The search identified 2,157 studies of which 85 studies were eligible for inclusion. The studies (n = 31 children, n = 10 adults, n = 44 mixed age) involved 12,800 patients (30% complicated dengue). The overall frequency of PE was 33% [95%CI: 29 to 37%] and the rate of PE increased significantly with disease severity (P = 0.001) such that in complicated vs. uncomplicated dengue the frequencies were 48% and 17% (P < 0.001). When assessing all studies, PE occurred significantly more often in children compared to adults (43% vs. 13%, P = 0.002) and lung ultrasound more frequently detected PE than conventional chest X-ray (P = 0.023). CONCLUSIONS: We found that 1/3 of dengue patients presented with PE and the frequency increased with severity and younger age. Importantly, lung ultrasound demonstrated the highest rate of detection. Our findings suggest that PE is a relatively common finding in dengue and that bedside imaging tools, such as lung ultrasound, potentially may enhance detection.


Asunto(s)
Dengue , Derrame Pleural , Dengue Grave , Adulto , Niño , Humanos , Dengue Grave/complicaciones , Dengue Grave/diagnóstico por imagen , Dengue Grave/epidemiología , Exudados y Transudados , Derrame Pleural/diagnóstico por imagen , Derrame Pleural/epidemiología , Derrame Pleural/complicaciones , Plasma , Ultrasonografía , Dengue/complicaciones , Dengue/diagnóstico por imagen , Dengue/epidemiología
15.
Mem Inst Oswaldo Cruz ; 118: e220255, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37162062

RESUMEN

BACKGROUND: Dengue is a disease caused by dengue virus (DENV-1 through -4). Among the four serotypes, DENV-4 remains the least studied. Acute kidney injury is a potential complication of dengue generally associated with severe dengue infection. OBJECTIVES: The goal of this study was to investigate the alterations caused by experimental dengue infection in the kidney of adult BALB/c mice. METHODS: In this study, BALB/c mice were infected through the intravenous route with a DENV-4 strain, isolated from a human patient. The kidneys of the mice were procured and subject to histopathological and ultrastructural analysis. FINDINGS: The presence of the viral antigen was confirmed through immunohistochemistry. Analysis of tissue sections revealed the presence of inflammatory cell infiltrate throughout the parenchyma. Glomerular enlargement was a common find. Necrosis of tubular cells and haemorrhage were also observed. Analysis of the kidney on a transmission electron microscope allowed a closer look into the necrotic tubular cells, which presented nuclei with condensed chromatin, and loss of cytoplasm. MAIN CONCLUSIONS: Even though the kidney is probably not a primary target of dengue infection in mice, the inoculation of the virus in the blood appears to damage the renal tissue through local inflammation.


Asunto(s)
Virus del Dengue , Dengue Grave , Adulto , Humanos , Animales , Ratones , Riñón , Antígenos Virales , Ratones Endogámicos BALB C
16.
Toxicol Lett ; 376: 26-38, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36638932

RESUMEN

Tributyltin (TBT) is an obesogenic endocrine disrupting chemical (EDC) linked with several metabolic complications. Brown adipose tissue (BAT) is the principal site for thermogenesis, making it a potential target for obesity management and metabolic disease. However, few studies have evaluated TBT effect on BAT function. In this investigation, we assessed whether subacute (15 days) and low dose of TBT exposure (100 ng/kg/day) results in abnormal BAT morphophysiology in adult male rats. Body temperature, BAT morphology, inflammation, oxidative stress, collagen deposition and BAT metabolic gene expression markers were assessed in room temperature (Room, ∼24 ºC) and after cold tolerance test (Cold, ∼4 ºC) conditions. A reduction in body temperature was observed in both Room and Cold conditions in TBT rats, suggesting abnormal BAT thermogenic function. Changes in BAT morphology were observed in TBT rats, with an increase in BAT lipid accumulation, an increase in BAT unilocular adipocyte number and a decrease in BAT multilocular adipocyte number in Room condition. All these parameters were opposite in Cold condition TBT rats, leading to a borderline increase in BAT UCP1 protein expression. An increase in BAT mast cell number was observed in TBT rats in Room condition. An increase in ED1 protein expression (macrophage marker) was observed in TBT rats in Cold condition. Oxidative stress and collagen deposition increased in both Room and Cold conditions in TBT rats. TBT exposure caused a borderline increase in BAT COL1A1 protein expression in Cold condition. Further, strong negative correlations were observed between body temperature and BAT lipid accumulation, and BAT lipid accumulation and multilocular adipocyte number. Thus, these data suggest that TBT exposure impaired BAT morphophysiology through impacts on lipid accumulation, inflammation, fibrosis and oxidative stress in male rats.


Asunto(s)
Tejido Adiposo Pardo , Obesidad , Ratas , Masculino , Animales , Obesidad/metabolismo , Tejido Adiposo Pardo/metabolismo , Inflamación/metabolismo , Colágeno/metabolismo , Lípidos
17.
Mem. Inst. Oswaldo Cruz ; 118: e220255, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1440671

RESUMEN

BACKGROUND Dengue is a disease caused by dengue virus (DENV-1 through -4). Among the four serotypes, DENV-4 remains the least studied. Acute kidney injury is a potential complication of dengue generally associated with severe dengue infection. OBJECTIVES The goal of this study was to investigate the alterations caused by experimental dengue infection in the kidney of adult BALB/c mice. METHODS In this study, BALB/c mice were infected through the intravenous route with a DENV-4 strain, isolated from a human patient. The kidneys of the mice were procured and subject to histopathological and ultrastructural analysis. FINDINGS The presence of the viral antigen was confirmed through immunohistochemistry. Analysis of tissue sections revealed the presence of inflammatory cell infiltrate throughout the parenchyma. Glomerular enlargement was a common find. Necrosis of tubular cells and haemorrhage were also observed. Analysis of the kidney on a transmission electron microscope allowed a closer look into the necrotic tubular cells, which presented nuclei with condensed chromatin, and loss of cytoplasm. MAIN CONCLUSIONS Even though the kidney is probably not a primary target of dengue infection in mice, the inoculation of the virus in the blood appears to damage the renal tissue through local inflammation.

18.
Front Microbiol ; 13: 1055536, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36466642

RESUMEN

Although vertical transmission of CHIKV has been reported, little is known about the role of placenta in the transmission of this virus and the effects of infection on the maternal-fetal interface. In this work we investigated five placentas from pregnant women who became infected during the gestational period. Four formalin-fixed paraffin-embedded samples of placenta (cases 1-4) were positive for CHIKV by RT-PCR. One (case 5) had no positive test of placenta, but had positive RT-PCR for CHIKV in the serum of the mother and the baby, confirming vertical transmission. The placentas were analyzed regarding histopathological and immunological aspects. The main histopathological changes were: deciduitis, villous edema, deposits, villous necrosis, dystrophic calcification, thrombosis and stem vessel obliteration. In infected placentas we noted increase of cells (CD8+ and CD163+) and pro- (IFN-γ and TNF-α) and anti-inflammatory (TGF-ß and IL-10) cytokines compared to control placentas. Moreover, CHIKV antigen was detected in decidual cell, trophoblastic cells, stroma villi, Hofbauer cells, and endothelial cells. In conclusion, CHIKV infection seems to disrupt placental homeostasis leading to histopathological alterations in addition to increase in cellularity and cytokines overproduction, evidencing an altered and harmful environment to the pregnant woman and fetus.

19.
PLoS One ; 17(11): e0277612, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36395285

RESUMEN

Mayaro virus (MAYV, Togaviridae) and Oropouche orthobunyavirus (OROV, Peribunyaviridae) are emerging enzootic arboviruses in Latin America. Outbreaks of febrile illness associated with MAYV and OROV have been reported among humans mainly in the northern region of Brazil since the 1980s, and recent data suggest these viruses have circulated also in more populated areas of western Brazil. MAYV shares mosquito vectors with yellow fever virus and it has been historically detected during yellow fever epidemics. Aiming to investigate the transmission of OROV and MAYV at the human-animal interface during a yellow fever, chikungunya and Zika outbreaks in Brazil, we conducted a retrospective molecular investigation in 810 wild and domestic animals, 106 febrile patients, and 22.931 vectors collected from 2016 to 2018 in Cuiaba and Campo Grande metropolitan regions, western Brazil. All samples tested negative for OROV and MAYV RNA by RT-qPCR. Findings presented here suggest no active circulation of MAYV and OROV in the sampled hosts. Active surveillance and retrospective investigations are instrumental approaches for the detection of cryptic and subclinical activity of enzootic arboviruses and together serve as a warning system to implement appropriate actions to prevent outbreaks.


Asunto(s)
Arbovirus , Orthobunyavirus , Fiebre Amarilla , Infección por el Virus Zika , Virus Zika , Animales , Humanos , Brasil/epidemiología , Estudios Retrospectivos , Orthobunyavirus/genética , Arbovirus/genética
20.
Medicine (Baltimore) ; 101(45): e31500, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36397371

RESUMEN

As newborns are highly vulnerable, they require essential care for adequate child development. This study aimed to assess the care provided to newborns during the first 28 days of life and identify factors associated with adequate care. This was a longitudinal study conducted with 415 mothers and full-term newborns from 4 public maternity hospitals in Natal, Brazil, in 2019. Assistance, socioeconomic, and demographic data were collected 3 times: 48 hours, 7 days, and 28 days after birth. Pearson's chi-square and Poisson regression tests were used with a confidence interval of 95%. Most mothers were between 20 and 29 years old (46.5%), had a high school or higher education (65.3%), a partner (79%), an income of ≤ 1 minimum wage (64, 6%), and were multiparous (62.9%). A total of 29 actions performed in maternity hospitals and 11 in primary healthcare were evaluated. Among the first, 8 (27.6%) were satisfactory; 11 (37.9%), partially satisfactory; and 10 (34.5%), unsatisfactory. In primary care, 2 actions (18.2%) were considered satisfactory; 3 (27.3%) partially satisfactory; and 6 (54.5%) unsatisfactory. In the multivariate analysis of the composite indicators related to adequacy of care, women undergoing vaginal delivery, those who are multiparous, and maternity hospitals at usual risk were associated with better adequacy of care indicators (P ≤ .05). Maternity hospitals accredited to the Baby-Friendly Hospital Initiative had lower chances of the adequacy of promotion to exclusive breastfeeding. The sample loss rate was 13.7% in the first week and 16.6% at the end of the study period. There was inadequacy in the performance of care actions for newborns regarding access and comprehensiveness of care. These weaknesses highlight the need for reassessing skills and coordinating actions in the child's healthcare network.


Asunto(s)
Cuidados Posteriores , Promoción de la Salud , Niño , Recién Nacido , Femenino , Embarazo , Humanos , Adulto Joven , Adulto , Estudios Longitudinales , Lactancia Materna , Maternidades
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