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1.
Crit Rev Oncol Hematol ; 199: 104389, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734280

RESUMO

Breast cancer (BC) is currently the most common malignant tumour in women and one of the leading causes of their death around the world. New and increasingly personalised diagnostic and therapeutic tools have been introduced over the last few decades, along with significant advances regarding the study and knowledge related to BC. The tumour microenvironment (TME) refers to the tumour cell-associated cellular and molecular environment which can influence conditions affecting tumour development and progression. The TME is composed of immune cells, stromal cells, extracellular matrix (ECM) and signalling molecules secreted by these different cell types. Ever deeper understanding of TME composition changes during tumour development and progression will enable new and more innovative therapeutic strategies to become developed for targeting tumours during specific stages of its evolution. This review summarises the role of BC-related TME components and their influence on tumour progression and the development of resistance to therapy. In addition, an account on the modifications in BC-related TME components associated with therapy is given, and the completed or ongoing clinical trials related to this topic are presented.


Assuntos
Neoplasias da Mama , Microambiente Tumoral , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Neoplasias da Mama/etiologia , Feminino , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Progressão da Doença
2.
Microbiol Res ; 285: 127739, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38763016

RESUMO

Clostridioides difficile may have a negative impact on gut microbiota composition in terms of diversity and abundance, thereby triggering functional changes supported by the differential presence of genes involved in significant metabolic pathways, such as short-chain fatty acids (SCFA). This work has evaluated shotgun metagenomics data regarding 48 samples from four groups classified according to diarrhea acquisition site (community- and healthcare facility-onset) and positive or negative Clostridioides difficile infection (CDI) result. The metagenomic-assembled genomes (MAGs) obtained from each sample were taxonomically assigned for preliminary comparative analysis concerning differences in composition among groups. The predicted genes involved in metabolism, transport, and signaling remained constant in microbiota members; characteristic patterns were observed in MAGs and genes involved in SCFA butyrate and acetate metabolic pathways for each study group. A decrease in genera and species, as well as relative MAG abundance with the presence of the acetate metabolism-related gene, was evident in the HCFO/- group. Increased antibiotic resistance markers (ARM) were observed in MAGs along with the genes involved in acetate metabolism. The results highlight the need to explore the role of acetate in greater depth as a potential protector of the imbalances produced by CDI, as occurs in other inflammatory intestinal diseases.


Assuntos
Acetatos , Clostridioides difficile , Infecções por Clostridium , Microbioma Gastrointestinal , Metagenoma , Metagenômica , Clostridioides difficile/genética , Acetatos/metabolismo , Humanos , Infecções por Clostridium/microbiologia , Ácidos Graxos Voláteis/metabolismo , Genoma Bacteriano , Butiratos/metabolismo , Redes e Vias Metabólicas/genética , Fezes/microbiologia , Diarreia/microbiologia
3.
Vaccine ; 42(15): 3445-3454, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38631956

RESUMO

Major histocompatibility complex class II (MHC-II) molecules are involved in immune responses against pathogens and vaccine candidates' immunogenicity. Immunopeptidomics for identifying cancer and infection-related antigens and epitopes have benefited from advances in immunopurification methods and mass spectrometry analysis. The mouse anti-MHC-II-DR monoclonal antibody L243 (mAb-L243) has been effective in recognising MHC-II-DR in both human and non-human primates. It has also been shown to cross-react with other animal species, although it has not been tested in livestock. This study used mAb-L243 to identify Staphylococcus aureus and Salmonella enterica serovar Typhimurium peptides binding to cattle and swine macrophage MHC-II-DR molecules using flow cytometry, mass spectrometry and two immunopurification techniques. Antibody cross-reactivity led to identifying expressed MHC-II-DR molecules, together with 10 Staphylococcus aureus peptides in cattle and 13 S. enterica serovar Typhimurium peptides in swine. Such data demonstrates that MHC-II-DR expression and immunocapture approaches using L243 mAb represents a viable strategy for flow cytometry and immunopeptidomics analysis of bovine and swine antigen-presenting cells.


Assuntos
Anticorpos Monoclonais , Macrófagos , Salmonella typhimurium , Staphylococcus aureus , Animais , Bovinos , Suínos/imunologia , Staphylococcus aureus/imunologia , Anticorpos Monoclonais/imunologia , Macrófagos/imunologia , Salmonella typhimurium/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Reações Cruzadas/imunologia , Citometria de Fluxo , Espectrometria de Massas , Camundongos
4.
Biochim Biophys Acta Rev Cancer ; 1879(1): 189064, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38158026

RESUMO

The tumour microenvironment (TME) is usually defined as a cell environment associated with tumours or cancerous stem cells where conditions are established affecting tumour development and progression through malignant cell interaction with non-malignant cells. The TME is made up of endothelial, immune and non-immune cells, extracellular matrix (ECM) components and signalling molecules acting specifically on tumour and non-tumour cells. Breast cancer (BC) is the commonest malignant neoplasm worldwide and the main cause of mortality in women globally; advances regarding BC study and understanding it are relevant for acquiring novel, personalised therapeutic tools. Studying canine mammary gland tumours (CMGT) is one of the most relevant options for understanding BC using animal models as they share common epidemiological, clinical, pathological, biological, environmental, genetic and molecular characteristics with human BC. In-depth, detailed investigation regarding knowledge of human BC-related TME and in its canine model is considered extremely relevant for understanding changes in TME composition during tumour development. This review addresses important aspects concerned with different methods used for studying BC- and CMGT-related TME that are important for developing new and more effective therapeutic strategies for attacking a tumour during specific evolutionary stages.


Assuntos
Neoplasias da Mama , Glândulas Mamárias Humanas , Neoplasias Mamárias Animais , Humanos , Animais , Cães , Feminino , Neoplasias Mamárias Animais/tratamento farmacológico , Comunicação Celular , Transdução de Sinais , Microambiente Tumoral
5.
Vet Parasitol ; 326: 110081, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38113611

RESUMO

B. bovis invasion of bovine erythrocytes requires tight junction formation involving AMA-1/RON2 complex interaction. RON2 has been considered a vaccine candidate since antibodies targeting the protein can inhibit parasite invasion of target cells; however, the mechanism controlling B. bovis RON2 interaction with red blood cells is not yet fully understood. This study was thus aimed at identifying B. bovis RON2 protein regions associated with interaction with bovine erythrocytes. Natural selection analysis of the ron2 gene identified predominantly negative selection signals in the C-terminal region. Interestingly, protein-cell and competition assays highlighted the RON2-C region's role in peptide 42918-mediated erythrocyte binding, probably to a sialoglycoprotein receptor. This peptide (1218SFIMVKPPALHCVLKPVETL1237) lies within an intrinsically disordered region of the RON2 secondary structure flanked by two helical residues. The study provides, for the first time, valuable insights into RON2's role in interaction with its target cells. Future studies are required for studying the peptide's potential as an anti-B. bovis vaccine component.


Assuntos
Babesia bovis , Vacinas , Animais , Bovinos , Epitopos , Proteínas de Protozoários/metabolismo , Peptídeos , Eritrócitos/parasitologia
6.
Comp Immunol Microbiol Infect Dis ; 102: 102074, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832162

RESUMO

INTRODUCTION: Clostridium perfringens is a gram-positive, anaerobic sporulating bacillus which can infect several hosts, thereby being considered the causative agent of many gut illnesses. Some studies have suggested that C. perfringens's virulence factors may negatively affect gut microbiota homeostasis by decreasing beneficial bacteria; however, studies have failed to evaluate the simultaneous presence of other pathogenic bacteria, such as C. difficile (another sporulating bacillus known to play a role in gut microbiota imbalance). Conscious of the lack of compelling data, this work has ascertained how such microorganisms' coexistence can be associated with a variation in gut microbiota composition, compared to that of C. perfringens colonisation. METHODS: PCR was thus used for identifying C. perfringens and C. difficile in 98 samples. Amplicon-based sequencing of 16S- and 18S-rRNA genes' V4 hypervariable region from such samples was used for determining the microbiota's taxonomical composition and diversity. RESULTS: Small differences were observed in bacterial communities' taxonomic composition and diversity; such imbalance was mainly associated with groups having hospital-acquired diarrhoea. CONCLUSION: The alterations reported herein may have been influenced by C. difficile and diarrhoea acquisition site, despite C. perfringens' ability to cause alterations in microbiota due to its virulence factors. Our findings highlight the need for a holistic view of gut microbiota.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Microbioma Gastrointestinal , Animais , Clostridium perfringens/genética , Clostridioides difficile/genética , Clostridioides , Infecções por Clostridium/microbiologia , Infecções por Clostridium/veterinária , Bactérias , Diarreia/veterinária , Fatores de Virulência/genética
7.
Mol Immunol ; 163: 86-103, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769577

RESUMO

Plasmodium vivax's biological complexity has restricted in vitro culture development for characterising antigens involved in erythrocyte invasion and their immunological relevance. The murine model is proposed as a suitable alternative in the search for therapeutic candidates since Plasmodium yoelii uses homologous proteins for its invasion. The AMA-1 protein is essential for parasite invasion of erythrocytes as it is considered an important target for infection control. This study has focused on functional PyAMA-1 peptides involved in host-pathogen interaction; the protein is located in regions under negative selection as determined by bioinformatics analysis. It was found that pyama1 has two highly conserved regions amongst species (>70%) under negative selection. Fourteen synthetic peptides spanning both conserved regions were evaluated; 5 PyAMA-1 peptides having high specific binding (HABP) to murine erythrocytes were identified. The parasite's invasion inhibition capability was analysed through in vitro assays, suggesting that peptides 42681 (43-ENTERSIKLINPWDKYMEKY-62), 42903 (206-RYSSNDANNENQPFSFTPEK-225) and 42904 (221-FTPEKIENYKDLSYLTKNLR-240) had greater than 50% inhibition profile and restricted P. yoelii intra-erythrocyte development. This work proposes that the screening of conserved HABPs under negative selective pressure might be good candidates for developing a synthetic anti-malarial vaccine since they share functionally-relevant characteristics, such as interspecies conservation, specific RBC binding profile, invasion and parasite development inhibition capability, and the predicted B-epitopes within were recognised by sera obtained from experimentally-infected mice.


Assuntos
Antimaláricos , Animais , Camundongos , Antimaláricos/farmacologia , Antimaláricos/metabolismo , Sequência de Aminoácidos , Plasmodium falciparum , Proteínas de Protozoários , Peptídeos , Eritrócitos/metabolismo , Antígenos de Protozoários
8.
Antibiotics (Basel) ; 12(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37627654

RESUMO

Candidiasis is an opportunistic infection affecting immunosuppressed and hospitalized patients, with mortality rates approaching 40% in Colombia. The growing pharmacological resistance of Candida species and the emergence of multidrug-resistant Candida auris are major public health problems. Therefore, different antimicrobial peptides (AMPs) are being investigated as therapeutic alternatives to control candidiasis effectively and safely. This work aimed to evaluate the in vitro antifungal activity of three synthetic AMPs, PNR20, PNR20-1, and 35409, against ATCC reference strains of Candida albicans, Candida glabrata, Candida parapsilosis, Candida krusei, and Candida tropicalis, and clinical isolates of C. auris. Antifungal susceptibility testing, determined by broth microdilution, showed that the AMPs have antifungal activity against planktonic cells of all Candida species evaluated. In C. auris and C. albicans, the peptides had an effect on biofilm formation and cell viability, as determined by the XTT assay and flow cytometry, respectively. Also, morphological alterations in the membrane and at the intracellular level of these species were induced by the peptides, as observed by transmission electron microscopy. In vitro, the AMPs had no cytotoxicity against L929 murine fibroblasts. Our results showed that the evaluated AMPs are potential therapeutic alternatives against the most important Candida species in Colombia and the world.

9.
World J Microbiol Biotechnol ; 39(8): 206, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37221438

RESUMO

Tuberculosis is a far-reaching, high-impact disease. It is among the top ten causes of death worldwide caused by a single infectious agent; 1.6 million tuberculosis-related deaths were reported in 2021 and it has been estimated that a third of the world's population are carriers of the tuberculosis bacillus but do not develop active disease. Several authors have attributed this to hosts' differential immune response in which cellular and humoral components are involved, along with cytokines and chemokines. Ascertaining the relationship between TB development's clinical manifestations and an immune response should increase understanding of tuberculosis pathophysiological and immunological mechanisms and correlating such material with protection against Mycobacterium tuberculosis. Tuberculosis continues to be a major public health problem globally. Mortality rates have not decreased significantly; rather, they are increasing. This review has thus been aimed at deepening knowledge regarding tuberculosis by examining published material related to an immune response against Mycobacterium tuberculosis, mycobacterial evasion mechanisms regarding such response and the relationship between pulmonary and extrapulmonary clinical manifestations induced by this bacterium which are related to inflammation associated with tuberculosis dissemination through different routes.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Citocinas , Inflamação , Saúde Pública
10.
Int J Mol Sci ; 24(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36982294

RESUMO

Bovine babesiosis is caused by the Apicomplexa parasites from the genus Babesia. It is one of the most important tick-borne veterinary diseases worldwide; Babesia bovis being the species associated with the most severe clinical signs of the disease and causing the greatest economic losses. Many limitations related to chemoprophylaxis and the acaricides control of transmitting vectors have led to the adoption of live attenuated vaccine immunisation against B. bovis as an alternative control strategy. However, whilst this strategy has been effective, several drawbacks related to its production have prompted research into alternative methodologies for producing vaccines. Classical approaches for developing anti-B. bovis vaccines are thus discussed in this review and are compared to a recent functional approach to highlight the latter's advantages when designing an effective synthetic vaccine targeting this parasite.


Assuntos
Babesia bovis , Babesia , Doenças dos Bovinos , Doenças Transmitidas por Carrapatos , Animais , Bovinos , Vacinas Atenuadas , Vacinas Sintéticas
11.
Int J Mol Sci ; 23(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36498854

RESUMO

Plasmodium vivax is the most widely distributed malaria parasite affecting humans worldwide, causing ~5 million cases yearly. Despite the disease's extensive burden, there are gaps in the knowledge of the pathophysiological mechanisms by which P. vivax invades reticulocytes. In contrast, this crucial step is better understood for P. falciparum, the less widely distributed but more often fatal malaria parasite. This discrepancy is due to the difficulty of studying P. vivax's exclusive invasion of reticulocytes, which represent 1-2% of circulating cells. Its accurate targeting mechanism has not yet been clarified, hindering the establishment of long-term continuous in vitro culture systems. So far, only three reticulocyte invasion pathways have been characterised based on parasite interactions with DARC, TfR1 and CD98 host proteins. However, exposing the parasite's alternative invasion mechanisms is currently being considered, opening up a large field for exploring the entry receptors used by P. vivax for invading host cells. New methods must be developed to ensure better understanding of the parasite to control malarial transmission and to eradicate the disease. Here, we review the current state of knowledge on cellular and molecular mechanisms of P. vivax's merozoite invasion to contribute to a better understanding of the parasite's biology, pathogenesis and epidemiology.


Assuntos
Malária Vivax , Malária , Humanos , Plasmodium vivax/metabolismo , Reticulócitos/metabolismo , Malária Vivax/parasitologia , Eritrócitos/metabolismo , Malária/metabolismo , Proteínas de Protozoários/metabolismo
12.
Viruses ; 14(12)2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36560678

RESUMO

The cervical microbiota is essential in female sexual health, and its altered states seem to have a central role in the dynamic of high-risk papillomavirus (hrHPV) infections. This study aimed to evaluate the variation in bacterial communities' compositions according to hrHPV. We collected two samples per woman, with a difference of 12 ± 1 months between them, and performed a follow-up on 66 of these women. The viral load (VL) of the hrHPV was estimated by quantitative PCR (qPCR), then it was normalized (using the HMBS gene as reference) and transformed to the Log10 scale to facilitate the interpretation. The VL was categorized as Negative, without hrHPV copies; Low, less than 100 hrHPV copies; Medium, between 100 to 102 hrHPV copies; and High, >102 hrHPV copies. The microbiota composition was described through the Illumina Novaseq PE250 platform. The diversity analyses revealed changes regarding the hrHPV VL, where women with low VL (<100 hrHPV copies) presented high diversity. The community state type (CST) IV was the most common. However, in women with high VL, a lower association with Lactobacillus depletion was found. Lactobacillus gallinarum and L. iners were the most abundant species in women with high VL, whereas women with low VL had a 6.06 greater probability of exhibiting Lactobacillus dominance. We identified conspicuous differences in the abundance of 78 bacterial genera between women with low and high VL, where 26 were depleted (e.g., Gardnerella) and 52 increased (e.g., Mycoplasma). A multilevel mixed-effects linear regression showed changes in the diversity due to the interaction between the measurement time and the VL, with a decrease in diversity in the second follow-up in women with low VL (Coeff. = 0.47), whereas the women with medium VL displayed an increase in diversity (Coeff. = 0.58). Here, we report for the first time that the cervical microbiota is influenced by the number of copies of hrHPV, where a decrease in the abundance of Lactobacillus, greater diversity, and enrichment of bacterial taxa is relevant in women with low VL.


Assuntos
Microbiota , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Papillomavirus Humano , Vagina , Colo do Útero/microbiologia , Microbiota/genética , Papillomaviridae/genética , Bactérias/genética
13.
Vet Parasitol ; 312: 109834, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36343530

RESUMO

Merozoite surface antigen-1 is a glycoprotein expressed by Babesia bovis and is considered a vaccine candidate given that antibodies against it are able to partially block in vitro invasion of bovine erythrocytes. Despite this, no study to date has confirmed the target cell binding properties of the full MSA-1 or its fragments. This research has thus been focused on identifying protein regions playing a role in erythrocyte attachment, based on genetic diversity and natural selection analysis. Two regions under functional constraint (nucleotides 134-428 and 464-629) having a preponderance of negatively-selected signals were identified in silico. Three non-overlapping peptides derived from functionally constraint regions (42422 (39PEGSFYDDMSKFYGAVGSFD58), 42424 (91NALIKNNPMIRPDLFNATIV110) and 42426 (150TDIVEEDREKAVEYFKKHVY169)) were able to specifically bind to a sialoglycoprotein located on the bovine erythrocyte surface as confirmed by sensitive and specific peptide-cell interaction competition assays using both enzymatically treated and untreated red blood cells. Interestingly, it was predicted that peptides 42422 and 42426 have a helical structure and conserved motifs in all strain/isolates. These findings provide evidence, for the first time, related to B. bovis MSA-1 short regions used by the parasite in erythrocyte binding which could be predicted using natural selection analysis. Future work focused on evaluating these peptides' antigenic ability during natural infection, and their ability to induce protection in immunisation assays are needed to confirm their usefulness as synthetic vaccine candidates.


Assuntos
Babesia bovis , Babesiose , Doenças dos Bovinos , Bovinos , Animais , Babesia bovis/genética , Proteína 1 de Superfície de Merozoito/genética , Antígenos de Protozoários , Eritrócitos/parasitologia , Doenças dos Bovinos/parasitologia , Babesiose/parasitologia , Proteínas de Protozoários
14.
Microbiol Spectr ; 10(5): e0050222, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36154277

RESUMO

Clostridioides difficile infection (CDI) creates an imbalance in the intestinal microbiota due to the interaction of the components making up this ecosystem, but little is known about the impact of this disease on other microbial members. This work has thus been aimed at evaluating the taxonomic composition, potential gene-associated functions, virulence factors, and antimicrobial resistance profiles of gut microbiomes. A total of 48 DNA samples obtained from patients with health care facility-acquired (HCFO) and community-onset (CO) diarrhea were distributed in the following four groups according to CDI status: HCFO/+ (n = 13), HCFO/- (n = 8), CO/+ (n = 13), and CO/- (n = 14). These samples were subjected to shotgun metagenomics sequencing. Although the CDI groups' microbiota had microbiome alterations, the greatest imbalance was observed in the in the HCFO+/- groups, with an increase in common pathogens and phage populations, as well as a decrease in beneficial microorganisms that leads to a negative impact on some intestinal homeostasis-related metabolic processes. A reduction in the relative abundance of butyrate metabolism-associated genes was also detected in the HCFO groups (P < 0.01), with an increase in some virulence factors and antibiotic-resistance markers. A set of 51 differentially abundant species in the groups with potential association to CDI enabled its characterization, leading to their spatial separation by onset. Strong correlations between phages and some archaeal and bacterial phyla were identified. This highlighted the need to study the microbiota's various components since their imbalance is multifactorial, with some pathogens contributing to a greater or lesser extent because of their interaction with the ecosystem they inhabit. IMPORTANCE Clostridioides difficile infection represents a serious public health problem in different countries due to its high morbi-mortality and the high costs it represents for health care systems. Studies have shown the impact of this infection on intestinal microbiome homeostasis, mainly on bacterial populations. Our research provides evidence of the impact of CDI at both the compositional (bacteria, archaea, and viruses), and functional levels, allowing us to understand that the alterations of the microbiota occur systemically and are caused by multiple perturbations generated by different members of the microbiota as well as by some pathogens that take advantage of the imbalance to proliferate. Likewise, the 51 differentially abundant species in the study groups with potential association to CDI found in this study could help us envisage future treatments against this and other inflammatory diseases, improving future therapeutic options for patients.


Assuntos
Anti-Infecciosos , Clostridioides difficile , Infecções por Clostridium , Microbiota , Humanos , Clostridioides difficile/genética , Infecções por Clostridium/microbiologia , Bactérias , Antibacterianos , Homeostase , Fatores de Virulência/genética , Butiratos
15.
Front Cell Infect Microbiol ; 12: 816574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433504

RESUMO

Plasmodium falciparum is the most lethal human malaria parasite, partly due to its genetic variability and ability to use multiple invasion routes via its binding to host cell surface receptors. The parasite extensively modifies infected red blood cell architecture to promote its survival which leads to increased cell membrane rigidity, adhesiveness and permeability. Merozoites are initially released from infected hepatocytes and efficiently enter red blood cells in a well-orchestrated process that involves specific interactions between parasite ligands and erythrocyte receptors; symptoms of the disease occur during the life-cycle's blood stage due to capillary blockage and massive erythrocyte lysis. Several studies have focused on elucidating molecular merozoite/erythrocyte interactions and host cell modifications; however, further in-depth analysis is required for understanding the parasite's biology and thus provide the fundamental tools for developing prophylactic or therapeutic alternatives to mitigate or eliminate Plasmodium falciparum-related malaria. This review focuses on the cellular and molecular events during Plasmodium falciparum merozoite invasion of red blood cells and the alterations that occur in an erythrocyte once it has become infected.


Assuntos
Malária Falciparum , Malária , Animais , Eritrócitos/parasitologia , Humanos , Malária/metabolismo , Malária Falciparum/metabolismo , Merozoítos , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
16.
Front Genet ; 13: 772885, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186024

RESUMO

The major histocompatibility complex (MHC) exerts great influence on responses to infectious diseases and vaccination due to its fundamental role in the adaptive immune system. Knowledge about MHC polymorphism distribution among breeds can provide insights into cattle evolution and diversification as well as population-based immune response variability, thus guiding further studies. Colombian Simmental and Simbrah cattle's BoLA-DRB3 genetic diversity was compared to that of taurine and zebuine breeds worldwide to estimate functional diversity. High allele richness was observed for Simmental and Simbrah cattle; nevertheless, high homozygosity was associated with individual low sequence variability in both the ß1 domain and the peptide binding region (PBR), thereby implying reduced MHC-presented peptide repertoire size. There were strong signals of positive selection acting on BoLA-DRB3 in all populations, some of which were poorly structured and displayed common alleles accounting for their high genetic similarity. PBR sequence correlation analysis suggested that, except for a few populations exhibiting some divergence at PBR, global diversity regarding potential MHC-presented peptide repertoire could be similar for the cattle populations analyzed here, which points to the retention of functional diversity in spite of the selective pressures imposed by breeding.

17.
Prev Vet Med ; 200: 105591, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35149317

RESUMO

Chlamydia psittaci is a highly zoonotic bacteria distributed worldwide; it is responsible for psittacosis, one of the most important infectious diseases affecting the Psittacidae, mostly parrots. This work was aimed at determining C. psittaci prevalence and genotype in 177 parrots confiscated in Colombia; cloacal swab (166) and faecal (177) samples were analysed from birds confiscated and housed in a Temporary Wildlife Reception Centre (Centro de Reception de Fauna Temporal). Conventional PCR was run on the samples for amplifying the MOMP gene and then the ompA gene. The C. psittaci genotype A was found in 81.3 % (144/177) of the birds analysed. Cloacal swabs accounted for 129/166 (77.7 %) positive samples and faecal matter for 53/177 (29.9 %), 38 birds proving positive for both types of sample; there was an 8.15 times greater probability of detection for cloacal swabs compared to faecal swabs (p < 0.05). Clinical examination findings were correlated with the animals' positivity for cloacal swabs, faecal matter or both, finding a statistically significant relationship with low respiratory rate (p < 0.05) and broken plumage for cloacal swab sample results (p < 0.1). Even though 85 % seroprevalence has previously been reported in Colombia using indirect ELISA, this study reports for the first time C. psittaci genotype A endemicity in psittacines in captivity in Colombia using molecular techniques, considering the zoonotic risk involved in having these birds as pets.


Assuntos
Doenças das Aves , Chlamydophila psittaci , Papagaios , Psitacose , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/microbiologia , Chlamydophila psittaci/genética , Colômbia/epidemiologia , Prevalência , Psitacose/epidemiologia , Psitacose/veterinária , Estudos Soroepidemiológicos
18.
PLoS One ; 17(1): e0262069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35077465

RESUMO

BACKGROUND: Cervical cancer (CC) promotion and prevention (P&P) programmes' challenge lies in guaranteeing that follow-up strategies have a real impact on reducing CC-related mortality rates. CC P&P programme compliance and coverage rates are relevant indicators for evaluating their success and good performance; however, such indicators' frequency rates are considerably lower among women living in rural and border areas. This study was aimed at identifying factors associated with CC screening programme attendance for women living in Colombia's Amazon region. METHODS: This study (qualitative and quantitative phases) was carried out between September 2015 and November 2016; women residing in the border towns of Leticia and Puerto Nariño participated in it. The first phase (qualitative) involved interviews and focus group discussions; this led to establishing factors related to CC P&P programme attendance which were used in the quantitative phase for designing a survey for determining the strength of association in a logistic regression model. The terms attendance and compliance were considered to apply to women who had followed the 1-1-3 scheme throughout their lives, i.e. a cytology examination every 3 years after receiving two consecutive negative annual cytology results. RESULTS: Inclusion criteria were met by 309 women (≥18-year-olds having an active sexual life, having resided in the target community for at least one year); 15.2% had suitable P&P programme follow-up. Screening programme attendance was positively associated with first intercourse after becoming 20 years-old (aOR: 3.87; 1.03-9.50 95%CI; p = 0.045), frequent contraceptive use (aOR: 3.11; 1.16-8.33 95%CI; p = 0.023), awareness of the age to participate in P&P programmes (aOR: 2.69; 1.08-6.68 95%CI; p = 0.032), awareness of cytology's usefulness in identifying cervical abnormalities (aOR: 2.43; 1.02-5.77 95%CI; p = 0.043) and considering cytology important (aOR: 2.64; 1.12-6.19 95%CI; p = 0.025). Women living in rural areas had a lower probability (aOR 0.43: 0.24-0.79 95%CI; p = 0.006) of adhering to CC P&P programmes. CONCLUSIONS: This study's findings suggested the need for including novel strategies in screening programmes which will promote CC P&P activities going beyond hospital outpatient attendance to reach the most remote or widely scattered communities, having the same guarantees regarding access, opportunity and quality. Including education-related activities and stimulating the population's awareness regarding knowledge about CC prevention could be one of the main tools for furthering the impact of attendance at and compliance with P&P programmes.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos
19.
Sci Rep ; 11(1): 22597, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799668

RESUMO

Trichomonas vaginalis (TV), the most common non-viral sexually-transmitted infection is considered a neglected infection and its epidemiology is not well known. This study determined TV-infection dynamics in a retrospective cohort of Colombian women and evaluated associations between risk factors and TV-outcome. TV was identified by PCR. Cox proportional risk models were used for evaluating the relationship between TV-outcome (infection, clearance and persistence) and risk factors (sexually-transmitted infections and sociodemographic characteristics). Two hundred and sixty-four women were included in the study; 26.1% had TV at the start of the study, 40.9% suffered at least one episode of infection and 13.0% suffered more than one episode of TV during the study. Women suffering HPV had a greater risk of TV-infection (aHR 1.59), high viral-load (> 102) for HPV-16 being related to a greater risk of persistent parasite infection; a high viral load (> 102) for HPV-18 and -33 was related to a lower probability of TV-clearance. Ethnicity (afrodescendent/indigenous people: aHR 5.11) and having had more than two sexual partners (aHR 1.94) were related to greater risk of infection, contrasting with women having a background of abortions and lower probability of having TV (aHR 0.50). Women aged 35- to 49-years-old (aHR 2.08), increased years of sexual activity (aHR 1.10), multiple sexual partners (aHR 8.86) and multiparous women (aHR 3.85) led to a greater probability of persistence. Women whose cervical findings worsened had a 9.99 greater probability of TV-persistence. TV distribution was high in the study population; its coexistence with HPV and other risk factors influenced parasite infection dynamics. The results suggested that routine TV detection should be considered regarding populations at risk of infection.


Assuntos
Vaginite por Trichomonas/epidemiologia , Vaginite por Trichomonas/terapia , Trichomonas vaginalis , Adolescente , Adulto , Idoso , Colômbia/epidemiologia , Colposcopia , Feminino , Papillomavirus Humano 16 , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Infecções por Papillomavirus , Reação em Cadeia da Polimerase , Probabilidade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Projetos de Pesquisa , Fatores de Risco , Carga Viral , Adulto Jovem
20.
Vaccines (Basel) ; 9(9)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34579225

RESUMO

Nowadays, safe and efficacious vaccines represent powerful and cost-effective tools for global health and economic growth. In the veterinary field, these are undoubtedly key tools for improving productivity and fighting zoonoses. However, cases of persistent infections, rapidly evolving pathogens having high variability or emerging/re-emerging pathogens for which no effective vaccines have been developed point out the continuing need for new vaccine alternatives to control outbreaks. Most licensed vaccines have been successfully used for many years now; however, they have intrinsic limitations, such as variable efficacy, adverse effects, and some shortcomings. More effective adjuvants and novel delivery systems may foster real vaccine effectiveness and timely implementation. Emerging vaccine technologies involving nanoparticles such as self-assembling proteins, virus-like particles, liposomes, virosomes, and polymeric nanoparticles offer novel, safe, and high-potential approaches to address many vaccine development-related challenges. Nanotechnology is accelerating the evolution of vaccines because nanomaterials having encapsulation ability and very advantageous properties due to their size and surface area serve as effective vehicles for antigen delivery and immunostimulatory agents. This review discusses the requirements for an effective, broad-coverage-elicited immune response, the main nanoplatforms for producing it, and the latest nanovaccine applications for fighting animal pathogens.

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