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1.
J Reprod Immunol ; 163: 104214, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508038

RESUMO

Although several testicular alterations promoted by coronavirus infection have been demonstrated, the extent, causes, and players of testicular pathogenesis are not totally understood. The present study aimed to investigate the short-term effects on male fertility of intranasally administered murine hepatitis virus strain 3 (MHV-3), a member of the genus Betacoronavirus, which causes a severe systemic acute infection. This mouse model might be used as a in vivo prototype for investigating the impact of betacoronavirus on the endocrine and exocrine testicular functions with the advantage to be performed in a biosafety level 2 condition. Herein, we performed virological, histopathological, and molecular studies regarding the testicular spermatogenesis and the spermatic quality analyses in an MHV-3-infected C57BL/6 mice. The main outcomes showed that MHV-3 infects mouse testis and induces a testicular inflammatory state, impairing the steroidogenic pathway. The infection led to several alterations in the testicular parenchyma, such as: seminiferous epithelium sloughing, retention of residual bodies, germ cell apoptosis, alterations in intercellular junction proteins, and worse spermatogenic parameters. Moreover, the levels of plasmatic testosterone as well as the quality of sperm production reduced. Therefore, the present data suggest that the viral/inflammatory impairment of the steroidogenic pathway and the consequent imbalance of androgen levels is critical in testicular pathology, disturbing the SC barrier function and the germ cell differentiation. Our study is important for comprehending the effects of beta coronavirus infections on testis function in order to develop treatments that could prevent virus-mediated male infertility.


Assuntos
Camundongos Endogâmicos C57BL , Vírus da Hepatite Murina , Espermatogênese , Espermatozoides , Testículo , Animais , Masculino , Camundongos , Testículo/virologia , Testículo/patologia , Testículo/imunologia , Espermatozoides/virologia , Espermatozoides/imunologia , Espermatozoides/patologia , Modelos Animais de Doenças , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/imunologia , Infertilidade Masculina/virologia , Infertilidade Masculina/imunologia , Infertilidade Masculina/patologia , Infertilidade Masculina/etiologia , Testosterona/sangue , Humanos
2.
Braz J Med Biol Res ; 53(12): e7851, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111742

RESUMO

The neutrophil is an important cell in host defense against infections, acting as the first line of microorganism control. However, this cell exhibits dysregulated activity in sepsis and may contribute to the pathogenesis of the disease. This systematic review aimed to highlight the major scientific findings regarding neutrophil activity in sepsis reported in clinical and experimental research published in the last 10 years. The search was conducted in the Virtual Health Library of PAHO-WHO (BVS) and PubMed databases, and articles published between January 2007 and May 2017 in Portuguese, English, and Spanish were eligible. Article selection was carried out independently by two reviewers (CB and IB). A total of 233 articles were found, of which 87 were identified on PubMed and 146 on BVS. Eighty-two articles were duplicates. Of the remaining 151 articles, 19 met the inclusion criteria after title, abstract, and full-text analysis. Overall, research in clinical samples and animal models of sepsis showed reduced capacity of neutrophils to migrate and delayed apoptosis, but there was no consensus on the phagocytic activity of neutrophils in sepsis. Molecules, such as pentraxin 3 (PTX3), have been analyzed as potential diagnostic markers in sepsis but the diversity of soluble molecules detected in blood samples of sepsis patients did not enable further understanding of the correlation of these circulating molecules with neutrophil activity during sepsis. Optimal understanding of the function of neutrophils in sepsis remains a challenge that, if overcome, would eventually allow targeted therapeutic interventions in patients affected by this severe syndrome.


Assuntos
Neutrófilos , Sepse , Animais , Apoptose , Humanos
3.
Braz. j. med. biol. res ; 53(12): e7851, 2020. graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132503

RESUMO

The neutrophil is an important cell in host defense against infections, acting as the first line of microorganism control. However, this cell exhibits dysregulated activity in sepsis and may contribute to the pathogenesis of the disease. This systematic review aimed to highlight the major scientific findings regarding neutrophil activity in sepsis reported in clinical and experimental research published in the last 10 years. The search was conducted in the Virtual Health Library of PAHO-WHO (BVS) and PubMed databases, and articles published between January 2007 and May 2017 in Portuguese, English, and Spanish were eligible. Article selection was carried out independently by two reviewers (CB and IB). A total of 233 articles were found, of which 87 were identified on PubMed and 146 on BVS. Eighty-two articles were duplicates. Of the remaining 151 articles, 19 met the inclusion criteria after title, abstract, and full-text analysis. Overall, research in clinical samples and animal models of sepsis showed reduced capacity of neutrophils to migrate and delayed apoptosis, but there was no consensus on the phagocytic activity of neutrophils in sepsis. Molecules, such as pentraxin 3 (PTX3), have been analyzed as potential diagnostic markers in sepsis but the diversity of soluble molecules detected in blood samples of sepsis patients did not enable further understanding of the correlation of these circulating molecules with neutrophil activity during sepsis. Optimal understanding of the function of neutrophils in sepsis remains a challenge that, if overcome, would eventually allow targeted therapeutic interventions in patients affected by this severe syndrome.


Assuntos
Humanos , Animais , Sepse , Neutrófilos , Apoptose
4.
Bone ; 125: 112-121, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31100533

RESUMO

Short-chain fatty acids (SCFAs) exert a variety of immune and metabolic functions by binding to G-protein-coupled receptors, mainly free fatty acid receptor 2 (FFAR2). However, the effects of SCFAs and FFARs on bone remodeling, especially in alveolar bone, have been less explored. In this study, we investigated the influence of the SCFA/FFAR2 axis on alveolar bone. Bone samples from wild-type (WT) and FFAR2-deficient mice (FFAR2-/-) were analyzed using micro-CT, histology and qPCR. WT and FFAR2-/- animals received a high-fiber diet (HFD) reported to increase circulating levels of SCFAs. Additionally, we analyzed the effects of SCFAs and a synthetic FFAR2 agonist, phenylacetamide-1 (CTMB), on bone cell differentiation. The participation of histone deacetylase inhibitors (iHDACs) in the effects of SCFAs was further assessed in vitro. CTMB treatment was also evaluated in vivo during orthodontic tooth movement (OTM). FFAR2-/- mice exhibited deterioration of maxillary bone parameters. Consistent with this, FFAR2-/- mice exhibited a significant increase of OTM and changes in bone cell numbers and in the expression of remodeling markers. The HFD partially reversed bone loss in the maxillae of FFAR2-/- mice. In WT mice, the HFD induced changes in the bone markers apparently favoring a bone formation scenario. In vitro, bone marrow cells from FFAR2-/- mice exhibited increased differentiation into osteoclasts, while no changes in osteoblasts were observed. In line with this, differentiation of osteoclasts was diminished by SCFAs and CTMB. Moreover, CTMB treatment significantly reduced OTM. Pretreatment of osteoclasts with iHDACs did not modify the effects of SCFAs on these cells. In conclusion, SCFAs function as regulators of bone resorption. The effects of SCFAs on osteoclasts are dependent on FFAR2 activation and are independent of the inhibition of HDACs. FFAR2 agonists may be useful to control bone osteolysis.


Assuntos
Ácidos Graxos Voláteis/farmacologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Reabsorção Óssea/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Receptores Acoplados a Proteínas G/genética , Microtomografia por Raio-X
5.
Inflammopharmacology ; 27(3): 539-548, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29855750

RESUMO

The Maytenus genus is a member of the Celastraceae family. Numerous medicinal uses were assigned to species of this genus, with the use of roots, bark, and leaves for the treatment of gastric ulcers, as anti-inflammatory, analgesic, antiallergic, antitumor, among others. Several studies have demonstrated that natural products derived from plants have an important role in the prevention and treatment of obesity. Accordingly, we evaluated the effect of Maytenus imbricata extracts in the treatment of obesity induced by diet rich in refined carbohydrate (HC). BALB/c mice were fed chow or HC diet for 8 weeks. At the beginning of the 9th week, the HC group was subdivided into three groups: (i) group of animals that continued to consume only HC diet; (ii) the group of animals fed HC diet supplemented with ethyl acetate extract of M. imbricata roots (HC + EAE); (iii) the group of animals fed HC diet supplemented with extract in hexane/ethyl ether (HC + HEE). The period of extracts supplementation was 4 weeks. It was observed that EAE and EHE when added to the HC diet modulated the metabolic and inflammatory changes, such as: reduced the adipocytes area, improved glucose intolerance, reduced the levels of triglycerides and resistin in serum, and the number of total leukocytes in blood. In the epididymal adipose tissue, the extracts reduced proinflammatory mediators' concentration. According to the results, it was concluded that the species Maytenus imbricata has the potential to be used for the treatment of obesity.


Assuntos
Celastraceae/química , Inflamação/tratamento farmacológico , Maytenus/química , Doenças Metabólicas/tratamento farmacológico , Extratos Vegetais/farmacologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Carboidratos/farmacologia , Dieta/efeitos adversos , Suplementos Nutricionais , Inflamação/metabolismo , Resistência à Insulina/fisiologia , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Triglicerídeos/metabolismo
6.
Scand J Immunol ; 87(3)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29363152

RESUMO

In the murine model, it was demonstrated that pro-inflammatory cytokines and chemokines are essential to the formation and modulation of Schistosoma-induced granulomatous inflammation. However, the relationship of these immune mediators and disease severity is hard to be established in naturally infected individuals. The current study evaluates the association between plasma concentrations of MIF, sTNF-R1, CCL3, CCL7 and CCL24 and schistosomiasis morbidity in Schistosoma mansoni-infected patients with a low parasite burden. For this propose, 97 S. mansoni-infected individuals were subjected to abdominal ultrasound analysis and clinical examination. Among them, 88 had plasma concentration of immune mediators estimated by ELISA assay. Multivariate linear regression models were used to evaluate the relationship between the plasma concentration of immune mediators and the variables investigated. Although most individuals presented low parasite burden, over 30% of them showed signs of fibrosis defined by ultrasound measurements and 2 patients had a severe form of schistosomiasis. No association between parasite burden and the plasma levels of chemokine/cytokines or disease severity was observed. There was a positive association between plasma concentration of CCL4, sTNF-R1, CCL3 and MIF with gall bladder thickness and/or with portal vein thickness that are liver fibrosis markers. In contrast, no association was found between CCL7 plasma concentrations with any of the schistosomiasis morbidity parameters evaluated. The data showed that CCL24, sTNFR1, MIF and CCL3 can be detected in plasma of S. mansoni-infected individuals and their concentration would be used as prognostic makers of Schistosoma-induced liver fibrosis, even in individuals with low parasite burden.


Assuntos
Quimiocina CCL24/sangue , Quimiocina CCL3/sangue , Quimiocina CCL7/sangue , Oxirredutases Intramoleculares/sangue , Cirrose Hepática/imunologia , Fatores Inibidores da Migração de Macrófagos/sangue , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Adolescente , Adulto , Idoso , Animais , Humanos , Fígado/irrigação sanguínea , Fígado/parasitologia , Fígado/patologia , Cirrose Hepática/parasitologia , Pessoa de Meia-Idade , Veia Porta/patologia , Esquistossomose mansoni/parasitologia , Adulto Jovem
7.
Parasitology ; 145(4): 430-442, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-27976601

RESUMO

We propose a taxonomic revision of the dixenous trypanosomatids currently classified as Endotrypanum and Leishmania, including parasites that do not fall within the subgenera L. (Leishmania) and L. (Viannia) related to human leishmaniasis or L. (Sauroleishmania) formed by leishmanias of lizards: L. colombiensis, L. equatorensis, L. herreri, L. hertigi, L. deanei, L. enriettii and L. martiniquensis. The comparison of these species with newly characterized isolates from sloths, porcupines and phlebotomines from central and South America unveiled new genera and subgenera supported by past (RNA PolII gene) and present (V7V8 SSU rRNA, Hsp70 and gGAPDH) phylogenetic analyses of the organisms. The genus Endotrypanum is restricted to Central and South America, comprising isolates from sloths and transmitted by phlebotomines that sporadically infect humans. This genus is the closest to the new genus Porcisia proposed to accommodate the Neotropical porcupine parasites originally described as L. hertigi and L. deanei. A new subgenus Leishmania (Mundinia) is created for the L. enriettii complex that includes L. martiniquensis. The new genus Zelonia harbours trypanosomatids from Neotropical hemipterans placed at the edge of the Leishmania-Endotrypanum-Porcisia clade. Finally, attention is drawn to the status of L. siamensis and L. australiensis as nomem nudums.


Assuntos
Leishmania/genética , Filogenia , Trypanosomatina/classificação , Animais , América Central/epidemiologia , Genes de Protozoários , Humanos , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Leishmaniose/transmissão , Lagartos/parasitologia , Tipagem Molecular , Porcos-Espinhos/parasitologia , Psychodidae/parasitologia , RNA Ribossômico/genética , Bichos-Preguiça/parasitologia , América do Sul/epidemiologia , Trypanosomatina/genética
8.
Epidemiol Infect ; 145(10): 2038-2052, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28502279

RESUMO

The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria. Bartonella and hemotropic mycoplasmas are bacteria that parasite different mammals' species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning of Bartonella spp. and Mycoplasma spp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil. Out of 322 bat samples collected, while 17 (5·28%) were positive to quantitative PCR for Bartonella spp. based on nuoG gene, 45 samples (13·97%) were positive to cPCR assays for hemoplasmas based on 16S rRNA gene. While seven sequences were obtained for Bartonella (nuoG) (n = 3), gltA (n = 2), rpoB (n = 1), ftsZ (n = 1), five 16S rRNA sequences were obtained for hemoplasmas. In the phylogenetic analysis, the Bartonella sequences clustered with Bartonella genotypes detected in bats sampled in Latin America countries. All five hemoplasmas sequences clustered together as a monophyletic group by Maximum Likelihood and Bayesian Inference analyses. The present work showed the first evidence of circulation of Bartonella spp. and hemoplasmas among bats in Brazil.


Assuntos
Infecções por Bartonella/veterinária , Bartonella/genética , Quirópteros , Infecções por Mycoplasma/veterinária , Mycoplasma/genética , Animais , Proteínas de Bactérias/genética , Bartonella/isolamento & purificação , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/microbiologia , Brasil/epidemiologia , DNA Bacteriano/genética , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Filogenia , Análise de Sequência de DNA/veterinária
9.
Stud Mycol ; 86: 1-28, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28348446

RESUMO

The order Chaetothyriales (Pezizomycotina, Ascomycetes) harbours obligatorily melanised fungi and includes numerous etiologic agents of chromoblastomycosis, phaeohyphomycosis and other diseases of vertebrate hosts. Diseases range from mild cutaneous to fatal cerebral or disseminated infections and affect humans and cold-blooded animals globally. In addition, Chaetothyriales comprise species with aquatic, rock-inhabiting, ant-associated, and mycoparasitic life-styles, as well as species that tolerate toxic compounds, suggesting a high degree of versatile extremotolerance. To understand their biology and divergent niche occupation, we sequenced and annotated a set of 23 genomes of main the human opportunists within the Chaetothyriales as well as related environmental species. Our analyses included fungi with diverse life-styles, namely opportunistic pathogens and closely related saprobes, to identify genomic adaptations related to pathogenesis. Furthermore, ecological preferences of Chaetothyriales were analysed, in conjuncture with the order-level phylogeny based on conserved ribosomal genes. General characteristics, phylogenomic relationships, transposable elements, sex-related genes, protein family evolution, genes related to protein degradation (MEROPS), carbohydrate-active enzymes (CAZymes), melanin synthesis and secondary metabolism were investigated and compared between species. Genome assemblies varied from 25.81 Mb (Capronia coronata) to 43.03 Mb (Cladophialophora immunda). The bantiana-clade contained the highest number of predicted genes (12 817 on average) as well as larger genomes. We found a low content of mobile elements, with DNA transposons from Tc1/Mariner superfamily being the most abundant across analysed species. Additionally, we identified a reduction of carbohydrate degrading enzymes, specifically many of the Glycosyl Hydrolase (GH) class, while most of the Pectin Lyase (PL) genes were lost in etiological agents of chromoblastomycosis and phaeohyphomycosis. An expansion was found in protein degrading peptidase enzyme families S12 (serine-type D-Ala-D-Ala carboxypeptidases) and M38 (isoaspartyl dipeptidases). Based on genomic information, a wide range of abilities of melanin biosynthesis was revealed; genes related to metabolically distinct DHN, DOPA and pyomelanin pathways were identified. The MAT (MAting Type) locus and other sex-related genes were recognized in all 23 black fungi. Members of the asexual genera Fonsecaea and Cladophialophora appear to be heterothallic with a single copy of either MAT-1-1 or MAT-1-2 in each individual. All Capronia species are homothallic as both MAT1-1 and MAT1-2 genes were found in each single genome. The genomic synteny of the MAT-locus flanking genes (SLA2-APN2-COX13) is not conserved in black fungi as is commonly observed in Eurotiomycetes, indicating a unique genomic context for MAT in those species. The heterokaryon (het) genes expansion associated with the low selective pressure at the MAT-locus suggests that a parasexual cycle may play an important role in generating diversity among those fungi.

10.
Braz J Med Biol Res ; 50(2): e5566, 2017 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-28198910

RESUMO

Acute graft-versus-host disease (aGVHD) and cytomegalovirus reactivation are important complications after allogeneic stem cell transplantation (alloHSCT). Here, we evaluated the impact of treatment with alemtuzumab on the occurrence of aGVHD, cytomegalovirus reactivation and survival after alloHSCT. This was a prospective cohort study conducted at the allo-HSCT unit of Hospital das Clínicas, Universidade Federal de Minas Gerais, Brazil, from January 2009 to December 2011. Fifty-seven patients who underwent alloHSCT were included. Forty-five (79%) patients had a malignant disease. Alemtuzumab was administered before the conditioning regimen at a dose of 1 mg/kg in children and 30 mg/day for 2 days in adults or children weighing more than 40 kg (a total dose of 60 mg) with a non-malignant disease or patients with a malignant disease and high-risk for GVHD mortality. Alemtuzumab was used in 23 (40%) patients, of whom 17 received a reduced-intensity conditioning. Eleven patients presented aGVHD (grade 2-4) and only 1 of them received alemtuzumab. Cumulative incidence of aGVHD (grade 2-4) at day 100 after transplantation (D+100) was 4 for patients receiving alemtuzumab and 29% for patients not receiving alemtuzumab. Cumulative incidence of cytomegalovirus reactivation for patients receiving or not alemtuzumab was 62 and 38%, respectively. Sixteen patients died in the first 100 days after alloHSCT, most of them due to bacterial sepsis. Only 2 patients died of aGVHD until D+100. Overall survival was 50% without any impact of alemtuzumab. Alemtuzumab effectively controlled aGVHD but increased the risk of cytomegalovirus reactivation without improving survival.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Infecções por Citomegalovirus/prevenção & controle , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Adolescente , Adulto , Alemtuzumab , Criança , Pré-Escolar , Citomegalovirus/fisiologia , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/virologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Transplante Homólogo , Ativação Viral/efeitos dos fármacos , Adulto Jovem
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