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1.
Cell ; 166(3): 691-702, 2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27426948

RESUMO

The prevailing view of the nuclear genetic code is that it is largely frozen and unambiguous. Flexibility in the nuclear genetic code has been demonstrated in ciliates that reassign standard stop codons to amino acids, resulting in seven variant genetic codes, including three previously undescribed ones reported here. Surprisingly, in two of these species, we find efficient translation of all 64 codons as standard amino acids and recognition of either one or all three stop codons. How, therefore, does the translation machinery interpret a "stop" codon? We provide evidence, based on ribosomal profiling and "stop" codon depletion shortly before coding sequence ends, that mRNA 3' ends may contribute to distinguishing stop from sense in a context-dependent manner. We further propose that such context-dependent termination/readthrough suppression near transcript ends enables genetic code evolution.


Assuntos
Códon de Terminação , Código Genético , Terminação da Transcrição Genética , Aminoácidos/genética , Animais , Bradyrhizobium/genética , Cilióforos/genética , Besouros/genética , RNA de Transferência
2.
Cell ; 155(1): 242-56, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24074872

RESUMO

The complex network of specialized cells and molecules in the immune system has evolved to defend against pathogens, but inadvertent immune system attacks on "self" result in autoimmune disease. Both genetic regulation of immune cell levels and their relationships with autoimmunity are largely undetermined. Here, we report genetic contributions to quantitative levels of 95 cell types encompassing 272 immune traits, in a cohort of 1,629 individuals from four clustered Sardinian villages. We first estimated trait heritability, showing that it can be substantial, accounting for up to 87% of the variance (mean 41%). Next, by assessing ∼8.2 million variants that we identified and confirmed in an extended set of 2,870 individuals, 23 independent variants at 13 loci associated with at least one trait. Notably, variants at three loci (HLA, IL2RA, and SH2B3/ATXN2) overlap with known autoimmune disease associations. These results connect specific cellular phenotypes to specific genetic variants, helping to explicate their involvement in disease.


Assuntos
Citometria de Fluxo/métodos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Doenças do Sistema Imunitário/genética , Polimorfismo de Nucleotídeo Único , Humanos , Fenótipo
3.
Int J Mol Sci ; 24(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37108346

RESUMO

Extracellular vesicles (EVs) mediate cell interactions in biological processes, such as receptor activation or molecule transfer. Estimates of variation by age and sex have been limited by small sample size, and no report has assessed the contribution of genetic factors to levels of EVs. Here, we evaluated blood levels of 25 EV and 3 platelet traits in 974 individuals (933 genotyped) and reported the first genome-wide association study (GWAS) on levels of these traits. EV levels all decreased with age, whereas the trend for their surface markers was more heterogeneous. Platelets and CD31dim platelet EVs significantly increased in females compared to males, although CD31 expression on both platelets and platelet EVs decreased in females. Levels of the other EV subsets were similar between sexes. GWAS revealed three statistically significant genetic signals associated with EV levels in the F10 and GBP1 genes and in the intergenic region between LRIG1 and KBTBD8. These add to a signal in the 3'UTR of RHOF associated with CD31 expression on platelets that was previously found to be associated with other platelet traits. These findings suggest that EV formation is not a simple, constant adjunct of metabolism but is under both age-related and genetic control that can be independent of the regulation of the levels of the cells from which the EVs derive.


Assuntos
Vesículas Extracelulares , Estudo de Associação Genômica Ampla , Masculino , Feminino , Humanos , Plaquetas/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Fenótipo , Fatores Etários
4.
Clin Immunol ; 235: 108777, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34116212

RESUMO

Everyone carries a set of genetic variants that contribute to regulation of the levels of blood cells, with unknown clinical impact. One of them, rs445 within the cell-cycle checkpoint gene CDK6, reduces the levels of myeloid cell types including granulocytes. We treated CD3+ T cells and whole blood with palbociclib in 41 individuals, who were stratified by genotype for analyses. In T cells we assessed cell cycle and apoptosis, whereas in whole blood, apoptosis in activated (CD11b+), unactivated (CD11b-) granulocytes, cytotoxic (CD8 + CD4-), and helper (CD8-CD4+) T cells. We find that rs445 modulates the immune response of CD8+ T cells. It also increases the level of apoptotic CD11b + activated granulocytes after palbociclib treatment, which, in synergy with neutropenia, may affect drug related adverse events. These results suggest that the effect of palbociclib treatment may depend on underlying genetically encoded individual immune response as well as the direct response to the drug.


Assuntos
Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Variação Genética , Piperazinas/farmacologia , Piridinas/farmacologia , Linfócitos T/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T/fisiologia
5.
J Eukaryot Microbiol ; 69(5): e12886, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35006645

RESUMO

The diversity of prokaryotic symbionts in Ciliophora and other protists is fascinatingly rich; they may even include some potentially pathogenic bacteria. In this review, we summarize currently available data on biodiversity and some morphological and biological peculiarities of prokaryotic symbionts mainly within the genera Paramecium and Euplotes. Another direction of ciliate symbiology, neglected for a long time and now re-discovered, is the study of epibionts of ciliates. This promises a variety of interesting outcomes. Last, but not least, we stress the new technologies, such as next generation sequencing and the use of genomics data, which all can clarify many new aspects of relevance. For this reason, a brief overview of achievements in genomic studies on ciliate's symbionts is provided. Summing up the results of numerous scientific contributions, we systematically update current knowledge and outline the prospects as to how symbiology of Ciliophora may develop in the near future.


Assuntos
Alveolados , Cilióforos , Bactérias/genética , Cilióforos/genética , Cilióforos/microbiologia , Filogenia , Simbiose
6.
Ann Hepatol ; 27(3): 100683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35151902

RESUMO

INTRODUCTION AND OBJECTIVES: De novo malignancies represent an important cause of death for liver transplant recipients. Our aim was to analyze predictors of extra-hepatic non-skin cancer (ESNSC) and the impact of ESNSC on the long-term outcome. PATIENTS: We examined data from patients transplanted between 2000 and 2005 and followed-up in five Italian transplant clinics with a retrospective observational cohort study. Cox Regression was performed to identify predictors of ESNSC. A 1:2 cohort sub-study was developed to analyze the impact of ESNSC on 10-year survival. RESULTS: We analyzed data from 367 subjects (median follow-up: 15 years). Patients with ESNSC (n = 47) more often developed post-LT diabetes mellitus (DM) (57.4% versus 35,9%, p = 0.004). At multivariate analysis, post-LT DM independently predicted ESNSC (HR 1.929, CI 1.029-3.616, p = 0.040). Recipients with ESNSC showed a lower 10-year survival than matched controls (46,8% versus 68,1%, p = 0.023). CONCLUSIONS: Post-LT DM seems to be a relevant risk factor for post-LT ESNSC. ESNSC could have a noteworthy impact on the long-term survival of LT recipients.


Assuntos
Diabetes Mellitus , Neoplasias Hepáticas , Transplante de Fígado , Diabetes Mellitus/etiologia , Seguimentos , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
7.
Int J Mol Sci ; 24(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36614075

RESUMO

The use of cryopreserved peripheral blood mononuclear cells is common in biological research. It is widely accepted that primary cells are rendered unusable by several freezing cycles, although this practice might be very helpful when the biological material is valuable and its re-collection is impractical. To determine the extent to which primary cells undergoing repeated freezing cycles are comparable to one another and to fresh samples, we evaluated overall lymphocyte viability, their proliferation and cytokine production capabilities, as well as the levels of 27 cell subtypes in ten human peripheral blood mononuclear cells frozen for five years and repeatedly thawed. As expected, we observed a progressive increase in cell death percentages on three rounds of thawing, but the frequency of the main lymphocyte subsets was stable across the three thawings. Nevertheless, we observed a significant reduction of B cell frequency in frozen samples compared to fresh ones. On repeated thawings and subsequent conventional stimulation, lymphocyte proliferation significantly decreased, and IL-10, IL-6, GM-CSF, IFN-gamma, and IL-8 showed a trend to lower values.


Assuntos
Criopreservação , Leucócitos Mononucleares , Humanos , Congelamento , Subpopulações de Linfócitos , Linfócitos B
8.
Mult Scler ; 27(9): 1332-1340, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33566725

RESUMO

BACKGROUND: Defective alleles within the PRF1 gene, encoding the pore-forming protein perforin, in combination with environmental factors, cause familial type 2 hemophagocytic lymphohistiocytosis (FHL2), a rare, severe autosomal recessive childhood disorder characterized by massive release of cytokines-cytokine storm. OBJECTIVE: The aim of this study was to determine the function of hypomorph PRF1:p.A91V g.72360387 G > A on multiple sclerosis (MS) and type 1 diabetes (T1D). METHODS: We cross-compare the association data for PRF1:p.A91V mutation derived from GWAS on adult MS and pediatric T1D in Sardinians. The novel association with T1D was replicated in metanalysis in 12,584 cases and 17,692 controls from Sardinia, the United Kingdom, and Scotland. To dissect this mutation function, we searched through the coincident association immunophenotypes in additional set of general population Sardinians. RESULTS: We report that PRF1:p.A91V, is associated with increase of lymphocyte levels, especially within the cytotoxic memory T-cells, at general population level with reduced interleukin 7 receptor expression on these cells. The minor allele increased risk of MS, in 2903 cases and 2880 controls from Sardinia p = 2.06 × 10-4, odds ratio OR = 1.29, replicating a previous finding, whereas it protects from T1D p = 1.04 × 10-5, OR = 0.82. CONCLUSION: Our results indicate opposing contributions of the cytotoxic T-cell compartment to MS and T1D pathogenesis.


Assuntos
Autoimunidade , Sistema Imunitário , Autoimunidade/genética , Criança , Humanos , Inflamação , Proteínas com Homeodomínio LIM , Proteínas Musculares , Mutação , Perforina/genética , Fatores de Transcrição
9.
J Immunol ; 203(12): 3179-3189, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31740485

RESUMO

In mice, the ability of naive T (TN) cells to mount an effector response correlates with TCR sensitivity for self-derived Ags, which can be quantified indirectly by measuring surface expression levels of CD5. Equivalent findings have not been reported previously in humans. We identified two discrete subsets of human CD8+ TN cells, defined by the absence or presence of the chemokine receptor CXCR3. The more abundant CXCR3+ TN cell subset displayed an effector-like transcriptional profile and expressed TCRs with physicochemical characteristics indicative of enhanced interactions with peptide-HLA class I Ags. Moreover, CXCR3+ TN cells frequently produced IL-2 and TNF in response to nonspecific activation directly ex vivo and differentiated readily into Ag-specific effector cells in vitro. Comparative analyses further revealed that human CXCR3+ TN cells were transcriptionally equivalent to murine CXCR3+ TN cells, which expressed high levels of CD5. These findings provide support for the notion that effector differentiation is shaped by heterogeneity in the preimmune repertoire of human CD8+ T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/imunologia , Receptores CXCR3/metabolismo , Adulto , Fatores Etários , Idoso , Animais , Biomarcadores , Células Cultivadas , Feminino , Humanos , Memória Imunológica , Imunofenotipagem , Ativação Linfocitária/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto Jovem
10.
N Engl J Med ; 376(17): 1615-1626, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-28445677

RESUMO

BACKGROUND: Genomewide association studies of autoimmune diseases have mapped hundreds of susceptibility regions in the genome. However, only for a few association signals has the causal gene been identified, and for even fewer have the causal variant and underlying mechanism been defined. Coincident associations of DNA variants affecting both the risk of autoimmune disease and quantitative immune variables provide an informative route to explore disease mechanisms and drug-targetable pathways. METHODS: Using case-control samples from Sardinia, Italy, we performed a genomewide association study in multiple sclerosis followed by TNFSF13B locus-specific association testing in systemic lupus erythematosus (SLE). Extensive phenotyping of quantitative immune variables, sequence-based fine mapping, cross-population and cross-phenotype analyses, and gene-expression studies were used to identify the causal variant and elucidate its mechanism of action. Signatures of positive selection were also investigated. RESULTS: A variant in TNFSF13B, encoding the cytokine and drug target B-cell activating factor (BAFF), was associated with multiple sclerosis as well as SLE. The disease-risk allele was also associated with up-regulated humoral immunity through increased levels of soluble BAFF, B lymphocytes, and immunoglobulins. The causal variant was identified: an insertion-deletion variant, GCTGT→A (in which A is the risk allele), yielded a shorter transcript that escaped microRNA inhibition and increased production of soluble BAFF, which in turn up-regulated humoral immunity. Population genetic signatures indicated that this autoimmunity variant has been evolutionarily advantageous, most likely by augmenting resistance to malaria. CONCLUSIONS: A TNFSF13B variant was associated with multiple sclerosis and SLE, and its effects were clarified at the population, cellular, and molecular levels. (Funded by the Italian Foundation for Multiple Sclerosis and others.).


Assuntos
Fator Ativador de Células B/genética , Mutação INDEL , Lúpus Eritematoso Sistêmico/genética , Esclerose Múltipla/genética , Autoimunidade , Fator Ativador de Células B/metabolismo , Estudos de Casos e Controles , Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Itália , Lúpus Eritematoso Sistêmico/imunologia , MicroRNAs , Esclerose Múltipla/imunologia , Fenótipo , Polimorfismo de Nucleotídeo Único , Risco , Análise de Sequência de RNA , Transcrição Gênica
11.
Langenbecks Arch Surg ; 405(3): 265-275, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32367395

RESUMO

BACKGROUND: Laparoscopic liver resection (LLR) has gained increasing acceptance for surgical treatment of malignant and benign liver tumors. LLR for intrahepatic cholangiocarcinoma (ICC) is not commonly performed because of the concern for the frequent need for major hepatectomy, vascular-biliary reconstructions, and lymph node dissection (LND). The aim of this present meta-analysis is to compare surgical and oncological outcomes of laparoscopic (LLR) versus open liver resection (OLR) for ICC. MATERIALS AND METHODS: A systematic review was conducted using the PubMed, MEDLINE, and Cochrane library database of published studies comparing LLR and OLR up to October 2019. Two reviewers independently assessed the eligibility and quality of the studies. Dichotomous data were calculated by odds ratio (OR), and continuous data were calculated by mean difference (MD) with 95% confidence intervals (95% CI). RESULTS: Four retrospective observational studies describing 204 patients met the inclusion criteria. With respect to surgical outcomes, laparoscopic compared with open liver resection was associated with lower blood loss [MD - 173.86, (95% CI - 254.82, -92.91) p < 0.0001], less requirement of blood transfusion [OR 0.34, (95% CI 0.14, 0.82) p = 0.02], less need for Pringle maneuver [OR 0.17, (95% CI 0.07, 0.43) p = 0.0002], shorter hospital stay [MD - 3.77, (95% CI - 5.09, - 2.44; p < 0.0001], and less morbidity [OR 0.44, (95% CI 0.21, 0.94) p = 0.03]. With respect to oncological outcomes, the LLR group was prone to lower rates of lymphadenectomy [OR 0.12, (95% CI 0.06, 0.25) p < 0.0001], but surgical margins R0 and recurrence rate were not significantly different. CONCLUSION: Laparoscopic liver resection for ICC seems to achieve better surgical outcomes, providing short-term benefits without negatively affecting oncologic adequacy in terms of R0 resections and disease recurrence. However, a higher LND rate was observed in the open group. Due to the risk of bias and the statistical heterogeneity between the studies included in this review, further RCTs are needed to reach stronger scientific conclusions.


Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/cirurgia , Hepatectomia , Laparoscopia , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Humanos
12.
Am J Primatol ; 82(4): e23106, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32072654

RESUMO

While the drivers of primate persistence in forest fragments have been often considered at the population level, the strategies to persist in these habitats have been little investigated at the individual or group level. Considering the rapid variation of fragment characteristics over time, longitudinal data on primates living in fragmented habitats are necessary to understand the key elements for their persistence. Since translocated animals have to cope with unfamiliar areas and face unknown fluctuations in food abundance, they offer the opportunity to study the factors contributing to successful migration between fragments. Here, we illustrated the evolution of the foraging strategies of translocated collared brown lemurs (Eulemur collaris) over an 18-year period in the Mandena Conservation Zone, south-east Madagascar. Our aim was to explore the ability of these frugivorous lemurs to adjust to recently colonized fragmented forests. Although the lemurs remained mainly frugivorous throughout the study period, over the years we identified a reduction in the consumption of leaves and exotic/pioneer plant species. These adjustments were expected in frugivorous primates living in a degraded area, but we hypothesize that they may also reflect the initial need to cope with an unfamiliar environment after the translocation. Since fragmentation is often associated with the loss of large trees and native vegetation, we suggest that the availability of exotic and/or pioneer plant species can provide an easy-to-access, nonseasonal food resource and be a key factor for persistence during the initial stage of the recolonization.


Assuntos
Comportamento Apetitivo , Dieta , Ecossistema , Lemuridae/fisiologia , Animais , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Comportamento Alimentar , Florestas , Frutas , Madagáscar
13.
Microb Ecol ; 77(4): 1092-1106, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30627761

RESUMO

We characterized a novel Holospora-like bacterium (HLB) (Alphaproteobacteria, Holosporales) living in the macronucleus of the brackish water ciliate Frontonia salmastra. This bacterium was morphologically and ultrastructurally investigated, and its life cycle and infection capabilities were described. We also obtained its 16S rRNA gene sequence and performed in situ hybridization experiments with a specifically-designed probe. A new taxon, "Candidatus Hafkinia simulans", was established for this HLB. The phylogeny of the family Holosporaceae based on 16S rRNA gene sequences was inferred, adding to the already available data both the sequence of the novel bacterium and those of other Holospora and HLB species recently characterized. Our phylogenetic analysis provided molecular support for the monophyly of HLBs and placed the new endosymbiont as the sister genus of Holospora. Additionally, the host ciliate F. salmastra, recorded in Europe for the first time, was concurrently described through a multidisciplinary study. Frontonia salmastra's phylogenetic position in the subclass Peniculia and the genus Frontonia was assessed according to 18S rRNA gene sequencing. Comments on the biodiversity of this genus were added according to past and recent literature.


Assuntos
Holosporaceae/fisiologia , Peniculina/microbiologia , Simbiose , Holosporaceae/classificação , Holosporaceae/genética , Holosporaceae/ultraestrutura , Itália , Macronúcleo/microbiologia , Microscopia Eletrônica de Transmissão , Peniculina/fisiologia , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , RNA Ribossômico 18S/análise , Análise de Sequência de DNA
14.
Microb Ecol ; 77(3): 748-758, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30105505

RESUMO

Symbioses between bacteria and eukaryotes are widespread and may have significant impact on the evolutionary history of symbiotic partners. The order Rickettsiales is a lineage of intracellular Alphaproteobacteria characterized by an obligate association with a wide range of eukaryotic hosts, including several unicellular organisms, such as ciliates and amoebas. In this work, we characterized the Rickettsiales symbionts associated with two different genotypes of the freshwater ciliate Paramecium caudatum originated from freshwater environments in distant geographical areas. Phylogenetic analyses based on 16S rRNA gene showed that the two symbionts are closely related to each other (99.4% identity), belong to the family Rickettsiaceae, but are far-related with respect to previously characterized Rickettsiales. Consequently, they were assigned to a new species of a novel genus, namely "Candidatus Spectririckettsia obscura." Screening on a database of short reads from 16S rRNA gene amplicon-based profiling studies confirmed that bacterial sequences related to the new symbiont are preferentially retrieved from freshwater environments, apparently with extremely scarce occurrence (< 0.1% positive samples). The present work provides new information on the still under-explored biodiversity of Rickettsiales, in particular those associated to ciliate host cells.


Assuntos
Paramecium caudatum/microbiologia , Rickettsiales/fisiologia , Simbiose , Brasil , DNA Bacteriano/genética , Índia , Filogenia , RNA Ribossômico 16S/genética , Rickettsiales/genética , Rickettsiales/isolamento & purificação
15.
AIDS Res Ther ; 14(1): 37, 2017 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-28779758

RESUMO

BACKGROUND: We hypothesized that frailty acts as a measure of health outcomes in the context of LT. The aim of this study was to explore frailty index across LT, as a measure of morbidity and mortality. This was a retrospective observational study including all consecutive 47 HIV+patients who received LT in Modena, Italy from 2003 to June 2015. METHODS: frailty index (FI) was constructed from 30 health variables. It was used both as a continuous score and as a categorical variable, defining 'most frail' a FI > 0.45. FI change across transplant (deltaFI, ΔFI) was calculated as the difference between year 1 FI (FI-Y1) and pre-transplant FI (FI-t0). The outcomes measures were mortality and "otpimal LT" (defined as being alive without multi-morbidity). RESULTS: Median value of FI-t0 was 0.48 (IQR 0.42-0.52), FI-Y1 was 0.31 (IQR 0.26-0.41). At year five mortality rate was 45%, "optimal transplant" rate at year 1 was 38%. All the patients who died in the post-LT were most frail in the pre-LT. ΔFI was a predictor of mortality after correction for age and MELD (HR = 1.10, p = 0.006) and was inversely associated with optimal transplant after correction for age (HR = 1.04, p = 0.01). CONCLUSIONS: We validated FI as a valuable health measure in HIV transplant. In particular, we found a relevant correlation between FI strata at baseline and mortality and a statistically significant correlation between, ΔFI and survival rate.


Assuntos
Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/cirurgia , Fragilidade/mortalidade , Infecções por HIV/patologia , Transplante de Fígado/mortalidade , Feminino , Infecções por HIV/virologia , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Invertebr Syst ; 382024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38980999

RESUMO

Chaetonotidae is the most diversified family of the entire phylum Gastrotricha; it comprises ~430 species distributed across 16 genera. The current classification, established mainly on morphological traits, has been challenged in recent years by phylogenetic studies, indicating that the cuticular ornamentations used to discriminate among species may be misleading when used to identify groupings, which has been the practice until now. Therefore, a consensus is developing toward implementing novel approaches to better define species identity and affiliation at a higher taxonomic ranking. Using an integrative morphological and molecular approach, including annotation of the mitogenome, we report on some freshwater gastrotrichs characterised by a mixture of two types of cuticular scales diagnostic of the genera Aspidiophorus and Heterolepidoderma . Our specimens' overall anatomical characteristics find no correspondence in the taxa of these two genera, calling for their affiliation to a new species. Phylogenetic analyses based on the sequence of the ribosomal RNA genes of 96 taxa consistently found the new species unrelated to Aspidiophorus or Heterolepidoderma but allied with Chaetonotus aff. subtilis, as a subset of a larger clade, including mostly planktonic species. Morphological uniqueness and position along the non-monophyletic Chaetonotidae branch advocate erecting a new genus to accommodate the current specimens; consequently, the name Litigonotus ghinii gen. nov., sp. nov. is proposed. The complete mitochondrial genome of the new taxon resulted in a single circular molecule 14,384 bp long, including 13 protein-coding genes, 17 tRNA genes and 2 rRNAs genes, showing a perfect synteny and collinearity with the only other gastrotrich mitogenome available, a possible hint of a high level of conservation in the mitochondria of Chaetonotidae. ZooBank: urn:lsid:zoobank.org:pub:9803F659-306F-4EC3-A73B-8C704069F24A.


Assuntos
Genoma Mitocondrial , Filogenia , Genoma Mitocondrial/genética , Animais , Especificidade da Espécie , Água Doce
17.
Nat Commun ; 15(1): 1093, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321113

RESUMO

The order Rickettsiales (Alphaproteobacteria) encompasses multiple diverse lineages of host-associated bacteria, including pathogens, reproductive manipulators, and mutualists. Here, in order to understand how intracellularity and host association originated in this order, and whether they are ancestral or convergently evolved characteristics, we built a large and phylogenetically-balanced dataset that includes de novo sequenced genomes and a selection of published genomic and metagenomic assemblies. We perform detailed functional reconstructions that clearly indicates "late" and parallel evolution of obligate host-association in different Rickettsiales lineages. According to the depicted scenario, multiple independent horizontal acquisitions of transporters led to the progressive loss of biosynthesis of nucleotides, amino acids and other metabolites, producing distinct conditions of host-dependence. Each clade experienced a different pattern of evolution of the ancestral arsenal of interaction apparatuses, including development of specialised effectors involved in the lineage-specific mechanisms of host cell adhesion and/or invasion.


Assuntos
Alphaproteobacteria , Rickettsiales , Rickettsiales/genética , Filogenia , Citoplasma , Alphaproteobacteria/genética , Metagenoma , Evolução Molecular
18.
Meat Sci ; 213: 109512, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38636339

RESUMO

The nutritional, antimicrobial, and antioxidant properties of bovine colostrum (BC) have encouraged its use in animal nutrition as a functional food in recent years. Nonetheless, the potential implications of BC supplementation on meat quality remain to be thoroughly assessed. To address this, thirty-nine New Zealand White rabbits (n = 13/group) were fed different dietary regimens until slaughter.: commercial standard diet for the control group (C) and C with 2.5% and 5% w/w of BC for BC-2.5 and BC-5 groups, respectively. Rabbits were slaughtered at 91 days of age and meat quality, and sensory characteristics were evaluated at days 2 (48 h after slaughter), 5, and 10 of refrigerated storage at 4 °C. The addition of colostrum in the diet resulted in a reduction of the total viable count, albeit only at the highest concentration and at the final detection, whereas for Lactobacillus spp. and Pseudomonas spp., there was little or no effect. The colour coordinates showed no differences between the groups, but they varied over time according to diet. Some differences between groups emerged in the definition of sensory attributes but did not affect the overall liking and overall scores of individual descriptors. These results indicate that the use of colostrum in rabbit feeding does not significantly impart meat quality and sensory attributes, but the potential of this valuable by-product for the food industry needs further investigation.


Assuntos
Ração Animal , Cor , Colostro , Dieta , Animais , Coelhos , Colostro/química , Bovinos , Ração Animal/análise , Feminino , Dieta/veterinária , Paladar , Masculino , Humanos , Carne/análise , Lactobacillus , Pseudomonas , Comportamento do Consumidor , Fenômenos Fisiológicos da Nutrição Animal
19.
Animals (Basel) ; 14(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38473185

RESUMO

Rabbits, pivotal in the EU as livestock, pets, and experimental animals, face bacterial infection challenges, prompting a quest for alternatives to curb antibiotic resistance. Bovine colostrum (BC), rich in immunoregulatory compounds, antimicrobial peptides, and growth factors, is explored for disease treatment and prevention. This study assesses BC diet supplementation effects on rabbit intestines, examining gene expression. Thirty female New Zealand White rabbits at weaning (35 days) were divided into three experimental groups: control (commercial feed), 2.5% BC, and 5% BC. The diets were administered until slaughtering (81 days). BC-upregulated genes in the jejunum included IL-8, TGF-ß, and CTNN-ß1 at 5% BC, while PLVAP at 2.5% BC. Antioxidant-related genes (SOD1, GSR) were downregulated in the cecum and colon with 2.5% BC. BC 5% promoted IL-8 in the jejunum, fostering inflammation and immune cell migration. It also induced genes regulating inflammatory responses (TGF-ß) and gastrointestinal permeability (CTNN-ß1). BC 5% enhanced antioxidant activity in the cecum and colon, but no significant impact on anti-myxo antibody production was observed. These results suggest that BC has significant effects on the rabbit gastrointestinal tract's inflammatory and antioxidant response, but further research is required to fully understand its histological and physiological impact.

20.
Metabolites ; 13(6)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37367919

RESUMO

The ever-increasing human population, the problem associated with climate change and recent crises-COVID-19 disease and trade conflicts-all impacted on the availability and cost of animal feed raw materials. This is clearly visible in realities which heavily rely on importation such as islands and small states, where producers involved in the agricultural sector were strongly affected by the sharp increase in prices. To deal with these global issues, alternative resources are perceived to replace conventional ingredients. This work aimed at assessing the nutritive value of different resources (sheep feed, mature carob, Maltese bread, wild asparagus, prickly lettuce, and loquat) for small ruminants present in the Maltese Islands, analyzing their chemical composition, gas production kinetics and antioxidant properties. In general, the variation in chemical composition resulted in different rumen fermentation kinetics (p < 0.007). The ratio between GP-24 h and GP-48 h was higher in Maltese bread than other substrates; loquat, prickly lettuce and wild asparagus showed lower fermentation kinetics in accordance with their high NDF and ADF contents. The antioxidant activity may be partially related to the polyphenolic content that was higher in wild asparagus, prickly lettuce and loquat. All feed characteristic confirmed their potential to be included as ingredients in ruminant diets and as a source of fiber.

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