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1.
BMC Genomics ; 25(1): 304, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519886

RESUMO

Fusarium, a member of the Ascomycota fungi, encompasses several pathogenic species significant to plants and animals. Some phytopathogenic species have received special attention due to their negative economic impact on the agricultural industry around the world. Traditionally, identification and taxonomic analysis of Fusarium have relied on morphological and phenotypic features, including the fungal host, leading to taxonomic conflicts that have been solved using molecular systematic technologies. In this work, we applied a phylogenomic approach that allowed us to resolve the evolutionary history of the species complexes of the genus and present evidence that supports the F. ventricosum species complex as the most basal lineage of the genus. Additionally, we present evidence that proposes modifications to the previous hypothesis of the evolutionary history of the F. staphyleae, F. newnesense, F. nisikadoi, F. oxysporum, and F. fujikuroi species complexes. Evolutionary analysis showed that the genome GC content tends to be lower in more modern lineages, in both, the whole-genome and core-genome coding DNA sequences. In contrast, genome size gain and losses are present during the evolution of the genus. Interestingly, core genome duplication events positively correlate with genome size. Evolutionary and genome conservation analysis supports the F3 hypothesis of Fusarium as a more compact and conserved group in terms of genome conservation. By contrast, outside of the F3 hypothesis, the most basal clades only share 8.8% of its genomic sequences with the F3 clade.


Assuntos
Fusarium , Fusarium/genética , Genoma Fúngico , Genômica , Tamanho do Genoma , Filogenia , Doenças das Plantas/microbiologia
2.
J Neurooncol ; 168(1): 99-109, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38630386

RESUMO

PURPOSE: Although ongoing studies are assessing the efficacy of new systemic therapies for patients with triple negative breast cancer (TNBC), the overwhelming majority have excluded patients with brain metastases (BM). Therefore, we aim to characterize systemic therapies and outcomes in a cohort of patients with TNBC and BM managed with stereotactic radiosurgery (SRS) and delineate predictors of increased survival. METHODS: We used our prospective patient registry to evaluate data from 2012 to 2023. We included patients who received SRS for TNBC-BM. A competing risk analysis was conducted to assess local and distant control. RESULTS: Forty-three patients with 262 tumors were included. The median overall survival (OS) was 16 months (95% CI 13-19 months). Predictors of increased OS after initial SRS include Breast GPA score > 1 (p < 0.001) and use of immunotherapy such as pembrolizumab (p = 0.011). The median time on immunotherapy was 8 months (IQR 4.4, 11.2). The median time to new CNS lesions after the first SRS treatment was 17 months (95% CI 12-22). The cumulative rate for development of new CNS metastases after initial SRS at 6 months, 1 year, and 2 years was 23%, 40%, and 70%, respectively. Thirty patients (70%) underwent multiple SRS treatments, with a median time of 5 months (95% CI 0.59-9.4 months) for the appearance of new CNS metastases after second SRS treatment. CONCLUSIONS: TNBC patients with BM can achieve longer survival than might have been previously anticipated with median survival now surpassing one year. The use of immunotherapy is associated with increased median OS of 23 months.


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/mortalidade , Pessoa de Meia-Idade , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/terapia , Idoso , Estudos Prospectivos , Adulto , Taxa de Sobrevida , Seguimentos , Prognóstico , Resultado do Tratamento , Sistema de Registros
3.
Neurosurg Rev ; 47(1): 307, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980428

RESUMO

Vestibular schwannomas (VS) are benign intracranial tumors posing significant management challenges. This study aims to compare the outcomes of stereotactic radiosurgery (SRS) and watchful waiting (WW) in the management of newly diagnosed VS, integrating findings from both retrospective and the pioneering V-REX prospective trial. Adhering to PRISMA guidelines, a systematic review was conducted using MEDLINE, Embase, and Cochrane databases. Studies directly comparing SRS with WW for newly diagnosed VS were included. Primary outcomes focused on hearing preservation assessed through the AAO-HNS or Gardner-Robertson hearing classification scales and tumor progression, with secondary outcomes focusing on neurological symptoms, and the need for further treatment. Thirteen studies encompassing 1,635 patients (WW: 891; SRS: 744) were included.While no significant difference was found in serviceable hearing loss at last follow-up (RR = 1.51, [95%CI: 0.98, 2.32], p = 0.06), significant differences favoring WW were observed in pure tone audiometry (PTA) (MD = -13.51 [95%CI: -22.66, -4.37], p = 0.004) and word recognition score (WRS) (MD = 20.48 [95%CI: 9.72, 31.25], p = 0.0002). Analysis of tumor progression indicated no overall significant difference in risk between SRS and WW (RR = 0.40, [95%CI 0.07, 2.40], p = 0.32), but subgroup analysis suggested a lower risk with SRS in certain contexts. The need for further treatments favored SRS (RR = 0.24, [95%CI: 0.07, 0.74], p = 0.007). No significant differences were found in tinnitus and imbalance between the two groups. This comprehensive analysis suggests no marked difference in functional hearing preservation between SRS and WW in managing VS. However, untreated tumors commonly necessitate additional interventions. These findings highlight the need for individualized treatment decisions and underscore the importance of continued monitoring. The study advocates for further prospective trials to refine management strategies for VS.


Assuntos
Neuroma Acústico , Radiocirurgia , Conduta Expectante , Humanos , Neuroma Acústico/terapia , Radiocirurgia/métodos , Resultado do Tratamento
4.
Stroke ; 54(8): 1974-1984, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37350270

RESUMO

BACKGROUND: Repeat stereotactic radiosurgery (SRS) for persistent cerebral arteriovenous malformation (AVM) has generally favorable patient outcomes. However, reporting studies are limited by small patient numbers and single-institution biases. The purpose of this study was to provide the combined experience of multiple centers, in an effort to fully define the role of repeat SRS for patients with arteriovenous malformation. METHODS: This multicenter, retrospective cohort study included patients treated with repeat, single-fraction SRS between 1987 and 2022. Follow-up began at repeat SRS. The primary outcome was a favorable patient outcome, defined as a composite of nidus obliteration in the absence of hemorrhage or radiation-induced neurological deterioration. Secondary outcomes were obliteration, hemorrhage risk, and symptomatic radiation-induced changes. Competing risk analysis was performed to compute yearly rates and identify predictors for each outcome. RESULTS: The cohort comprised 505 patients (254 [50.3%] males; median [interquartile range] age, 34 [15] years) from 14 centers. The median clinical and magnetic resonance imaging follow-up was 52 (interquartile range, 61) and 47 (interquartile range, 52) months, respectively. At last follow-up, favorable outcome was achieved by 268 (53.1%) patients (5-year probability, 50% [95% CI, 45%-55%]) and obliteration by 300 (59.4%) patients (5-year probability, 56% [95% CI, 51%-61%]). Twenty-eight patients (5.6%) experienced post-SRS hemorrhage with an annual incidence rate of 1.38 per 100 patient-years. Symptomatic radiation-induced changes were evident in 28 (5.6%) patients, with most occurring in the first 3 years. Larger nidus volumes (between 2 and 4 cm3, subdistribution hazard, 0.61 [95% CI, 0.44-0.86]; P=0.005; >4 cm3, subdistribution hazard, 0.47 [95% CI, 0.32-0.7]; P<0.001) and brainstem/basal ganglia involvement (subdistribution hazard, 0.6 [95% CI, 0.45-0.81]; P<0.001) were associated with reduced probability of favorable outcome. CONCLUSIONS: Repeat SRS confers reasonable obliteration rates with a low complication risk. With most complications occurring in the first 3 years, extending the latency period to 5 years generally increases the rate of favorable patient outcomes and reduces the necessity of a third intervention.


Assuntos
Malformações Arteriovenosas Intracranianas , Radiocirurgia , Masculino , Humanos , Adulto , Feminino , Resultado do Tratamento , Seguimentos , Estudos Retrospectivos , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/radioterapia , Malformações Arteriovenosas Intracranianas/cirurgia
5.
J Exp Bot ; 74(21): 6588-6607, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37656729

RESUMO

Trichomes are specialized epidermal cells in aerial plant parts. Trichome development proceeds in three stages, determination of cell fate, specification, and morphogenesis. Most genes responsible for these processes have been identified in the unicellular branched leaf trichomes from the model Arabidopsis thaliana. Less is known about the molecular basis of multicellular trichome formation across flowering plants, especially those formed in floral organs of early diverging angiosperms. Here, we aim to identify the genetic regulatory network (GRN) underlying multicellular trichome development in the kettle-shaped trap flowers of Aristolochia (Aristolochiaceae). We selected two taxa for comparison, A. fimbriata, with trichomes inside the perianth, which play critical roles in pollination, and A. macrophylla, lacking specialized trichomes in the perianth. A detailed morphoanatomical characterization of floral epidermis is presented for the two species. We compared transcriptomic profiling at two different developmental stages in the different perianth portions (limb, tube, and utricle) of the two species. Moreover, we present a comprehensive expression map for positive regulators and repressors of trichome development, as well as cell cycle regulators. Our data point to extensive modifications in gene composition, expression, and putative roles in all functional categories when compared with model species. We also record novel differentially expressed genes (DEGs) linked to epidermis patterning and trichome development. We thus propose the first hypothetical genetic regulatory network (GRN) underlying floral multicellular trichome development in Aristolochia, and pinpoint key factors responsible for the presence and specialization of floral trichomes in phylogenetically distant species of the genus.


Assuntos
Arabidopsis , Aristolochia , Aristolochiaceae , Tricomas/metabolismo , Aristolochia/genética , Aristolochiaceae/genética , Transcriptoma , Redes Reguladoras de Genes , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas
6.
J Neurooncol ; 164(2): 387-396, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37691032

RESUMO

PURPOSE: Patients with EGFR-mutated NSCLC represent a unique subset of lung cancer patients with distinct clinical and molecular characteristics. Previous studies have shown a higher incidence of brain metastases (BM) in this subgroup of patients, and neurologic death has been reported to be as high as 40% and correlates with leptomeningeal disease (LMD). METHODS: Between 2012 and 2021, a retrospective review of our prospective registry identified 606 patients with BM from NSCLC, with 170 patients having an EGFR mutation. Demographic, clinical, radiographic, and treatment characteristics were correlated to the incidence of LMD and survival. RESULTS: LMD was identified in 22.3% of patients (n = 38) at a median follow-up of 19 (2-98) months from initial SRS. Multivariate regression analysis showed targeted therapy and a cumulative number of metastases as significant predictors of LMD (p = 0.034, HR = 0.44), (p = .04, HR = 1.02). The median survival time after SRS of the 170 patients was 24 months (CI 95% 19.1-28.1). In a multivariate Cox regression analysis, RPA, exon 19 deletion, and osimertinib treatment were significant predictors of overall survival. The cumulative incidence of neurological death at 2 and 4 years post initial stereotactic radiosurgery (SRS) was 8% and 11%, respectively, and correlated with LMD. CONCLUSION: The study shows that current-generation targeted therapy for EGFR-mutated NSCLC patients may prevent the development and progression of LMD, leading to improved survival outcomes. Nevertheless, LMD is associated with poor outcomes and neurologic death, making innovative strategies to treat LMD essential.

7.
Fish Shellfish Immunol ; 140: 108928, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37423403

RESUMO

The probiotic potential of a designed bacterial consortia isolated from a competitive exclusion culture originally obtained from the intestinal contents of tilapia juveniles were evaluated on Nile tilapia alevins. The growth performance, intestinal histology, microbiota effects, resistance to Streptococcus agalactiae challenge, and immune response were assessed. In addition, the following treatments were included in a commercial feed: A12+M4+M10 (Lactococcus lactis A12, Priestia megaterium M4, and Priestia sp. M10), M4+M10 (P. megaterium M4, and Priestia sp. M10) and the single bacteria as controls; A12 (L. lactis A12), M4 (P. megaterium M4), M10 (Priestia sp. M10), also a commercial feed without any probiotic addition was included as a control. The results showed that all probiotic treatments improved the growth performance, intestinal histology, and resistance during experimental infection with S. agalactiae in comparison to the control fish. Also, the administration of probiotics resulted in the modulation of genes associated with the innate and adaptive immune systems that were non-dependent on microbial colonization. Surprisingly, L. lactis A12 alone induced benefits in fish compared to the microbial consortia, showing the highest increase in growth rate, survival during experimental infection with S. agalactiae, increased intestinal fold length, and the number of differentially expressed genes. Lastly, we conclude that a competitive exclusion culture is a reliable source of probiotics, and monostrain L. lactis A12 has comparable or even greater probiotic potential than the bacterial consortia.


Assuntos
Ciclídeos , Doenças dos Peixes , Microbioma Gastrointestinal , Probióticos , Tilápia , Animais , Probióticos/farmacologia , Dieta/veterinária , Ração Animal/análise , Suplementos Nutricionais
8.
J Neurooncol ; 158(3): 471-480, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35665462

RESUMO

PURPOSE: New therapies for melanoma have been associated with increasing survival expectations, as opposed to the dismal outcomes of only a decade ago. Using a prospective registry, we aimed to define current survival goals for melanoma patients with brain metastases (BM), based on state-of-the-art multimodality care. METHODS: We reviewed 171 melanoma patients with BM receiving stereotactic radiosurgery (SRS) who were followed with point-of-care data collection between 2012 and 2020. Clinical, molecular and imaging data were collected, including systemic treatment and radiosurgical parameters. RESULTS: Mean age was 63 ± 15 years, 39% were female and 29% had BRAF-mutated tumors. Median overall survival after radiosurgery was 15.7 months (95% Confidence Interval 11.4-27.7) and 25 months in patients managed since 2015. Thirty-two patients survived [Formula: see text] 5 years from their initial SRS. BRAF mutation-targeted therapies showed a survival advantage in comparison to chemotherapy (p = 0.009), but not to immunotherapy (p = 0.09). In a multivariable analysis, both immunotherapy and the number of metastases at 1st SRS were predictors of long-term survival ([Formula: see text] 5 years) from initial SRS (p = 0.023 and p = 0.018, respectively). Five patients (16%) of the long-term survivors required no active treatment for [Formula: see text] 5 years. CONCLUSION: Long-term survival in patients with melanoma BM is achievable in the current era of SRS combined with immunotherapies. For those alive [Formula: see text] 5 years after first SRS, 16% had been also off systemic or local brain therapy for over 5 years. Given late recurrences of melanoma, caution is warranted, however prolonged survival off active treatment in a subset of our patients raises the potential for cure.


Assuntos
Neoplasias Encefálicas , Melanoma , Radiocirurgia , Idoso , Neoplasias Encefálicas/patologia , Feminino , Humanos , Imunoterapia , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Radiocirurgia/métodos , Estudos Retrospectivos
9.
AIDS Res Ther ; 19(1): 42, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104716

RESUMO

BACKGROUND: Although combined antiretroviral therapy (cART) has decreased the mortality associated with HIV infection, complete immune reconstitution is not achieved despite viral suppression. Alterations of CD8+ T cells and some of their subpopulations, such as interleukin (IL)-17-producing cells, are evidenced in treated individuals and are associated with systemic inflammation and adverse disease outcomes. We sought to evaluate if different CD8+ T cell subsets are differentially normalized during a clinical follow-up of people living with HIV (PLWH) receiving suppressive cART. METHODS: We explored the changes in the frequencies, activation/exhaustion phenotypes (HLA-DR, CD38, PD-1, and TIM-3), and function (total and HIV-specific cells expressing CD107a, perforin, granzyme B, interferon [IFN]-γ and IL-17) of CD8+ T cells from early-treated PLWH receiving cART in a 1-year follow-up, using a multidimensional flow cytometry approach. RESULTS: Despite continuous cART-induced viral suppression and recovery of CD4+ T cells, after a 1-year follow-up, the CD8+ T cell counts, CD4:CD8 ratio, PD-1 expression, and IL-17 production by CD8+ T cells exhibited incomplete normalization compared with seronegative controls. However, the proportion of CD8+ T cells with an exhausted phenotype (co-expressing PD-1 andTIM-3), and cells co-expressing cytotoxic molecules (Perforin and Granzyme B), reached normalization. CONCLUSIONS: Although suppressive cART achieves normalization of CD4+ T cell counts, only particular subsets of CD8+ T cells are more rapidly normalized in PLWH receiving cART, which could be routinely used as biomarkers for therapy efficiency in these patients.


Assuntos
Infecções por HIV , Linfócitos T CD8-Positivos , Granzimas/metabolismo , Granzimas/uso terapêutico , Humanos , Interleucina-17/metabolismo , Interleucina-17/uso terapêutico , Perforina/metabolismo , Perforina/uso terapêutico , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/uso terapêutico , Subpopulações de Linfócitos T
10.
Curr Microbiol ; 79(2): 39, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982251

RESUMO

Mycobacterium tuberculosis (Mtb) is a successful pathogen causing tuberculosis (TB) disease in humans. It has been shown, that some circulating strains of Mtb in TB endemic populations, are more virulent and more transmissible than others, which may be related to their evolved adaptations to modulate the host immune responses. Underlying these adaptations to the stressful conditions, different genetic regulatory networks involved sRNAs that are mostly unknown for Mtb. We have previously shown that Mcr11 is one of the main sRNAs that determine transcriptomic differences among the Colombian clinical isolates UT127 and UT205 compared to the laboratory strain H37Rv. We found that the knock-down of mcr11 using CRISPRi has a major impact on phenotypic traits, especially in the clinical isolate UT205. Through the analysis of RNA-seq during the knock-down of mcr11 in UT205, we found a downregulation of genes mainly involved in lipid synthesis, lipid metabolism, ribosomal proteins, transport systems, respiratory and energy systems, membrane and cell wall components, intermediary metabolism, lipoproteins and virulence genes. One of the most interesting genes showing transcriptomic changes is OprA (encoded by the gene rv0516c), which has been involved in the K+ regulation. Overall, our data may suggest that one of the prominent roles of the sRNA Mcr11 is to regulate genes that control Mtb growth and osmoregulation.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Parede Celular , Humanos , Mycobacterium tuberculosis/genética , Transcriptoma , Virulência/genética
11.
Int J Mol Sci ; 23(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35163386

RESUMO

Zoonotic visceral leishmaniosis caused by Leishmania infantum is an endemic disease in the Mediterranean Basin affecting mainly humans and dogs, the main reservoir. The leishmaniosis outbreak declared in the Community of Madrid (Spain) led to a significant increase in human disease incidence without enhancing canine leishmaniosis prevalence, suggesting a better adaptation of the outbreak's isolates by other host species. One of the isolates obtained in the focus, IPER/ES/2012/BOS1FL1 (BOS1FL1), has previously demonstrated a different phenotype than the reference strain MCAN/ES/1996/BCN150 (BCN150), characterized by a lower infectivity when interacting with canine macrophages. Nevertheless, not enough changes in the cell defensive response were found to support their different behavior. Thus, we decided to investigate the molecular mechanisms involved in the interaction of both parasites with DH82 canine macrophages by studying their transcriptomic profiles developed after infection using RNA sequencing. The results showed a common regulation induced by both parasites in the phosphoinositide-3-kinase-protein kinase B/Akt and NOD-like receptor signaling pathways. However, other pathways, such as phagocytosis and signal transduction, including tumor necrosis factor, mitogen-activated kinases and nuclear factor-κB, were only regulated after infection with BOS1FL1. These differences could contribute to the reduced infection ability of the outbreak isolates in canine cells. Our results open a new avenue to investigate the true role of adaptation of L. infantum isolates in their interaction with their different hosts.


Assuntos
Cães/genética , Cães/parasitologia , Leishmania infantum/patogenicidade , Leishmaniose Visceral/genética , Leishmaniose Visceral/veterinária , Estágios do Ciclo de Vida/fisiologia , Macrófagos/parasitologia , Transcriptoma/genética , Animais , Linhagem Celular , Regulação da Expressão Gênica , Ontologia Genética , Leishmania infantum/crescimento & desenvolvimento , Leishmaniose Visceral/parasitologia , Macrófagos/metabolismo , Proteínas NLR/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Virulência
12.
Int J Mol Sci ; 23(3)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35163725

RESUMO

Tuberculosis (TB) is caused by Mycobacterium tuberculosis (Mtb), leading to pulmonary and extrapulmonary TB, whereby Mtb is disseminated to many other organs and tissues. Dissemination occurs early during the disease, and bacteria can be found first in the lymph nodes adjacent to the lungs and then later in the extrapulmonary organs, including the spleen. The early global gene expression response of human tissue macrophages and intracellular clinical isolates of Mtb has been poorly studied. Using dual RNA-seq, we have explored the mRNA profiles of two closely related clinical strains of the Latin American and Mediterranean (LAM) family of Mtb in infected human splenic macrophages (hSMs). This work shows that these pathogens mediate a distinct host response despite their genetic similarity. Using a genome-scale host-pathogen metabolic reconstruction to analyze the data further, we highlight that the infecting Mtb strain also determines the metabolic response of both the host and pathogen. Thus, macrophage ontogeny and the genetic-derived program of Mtb direct the host-pathogen interaction.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Interações Hospedeiro-Patógeno/genética , Humanos , Macrófagos/metabolismo , Mycobacterium tuberculosis/genética , RNA-Seq , Tuberculose/microbiologia
13.
Mol Phylogenet Evol ; 161: 107185, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33932614

RESUMO

Apicomplexa is a phylum of parasitic protozoa; among them are the order Haemosporida, vector-borne parasites that include those that cause malaria (genus Plasmodium). Most Apicomplexa species have a non-photosynthetic plastid or apicoplast. Given its unique metabolic pathways, this organelle is considered a target for malaria therapeutics. Regardless of its importance, there is a paucity of complete apicoplast genome data hindering comparative studies. Here, the Haemoproteus (Haemoproteus) columbae apicoplast genome (lineage HAECOL1) was obtained using next-generation sequencing. This genome was included in a comparative analysis with other plastids. This 29.8 kb circular genome shares the same structure found in Plasmodium parasites. It is A + T rich (87.7%), comparable but at the higher end of A + T content observed in Plasmodium species (85.5-87.2%). As expected, considering its high A + T content, the synonymous codon usage (RSCU) and the effective number of codons (ENc) showed a moderate codon bias. Several apicoplast genes have a phylogenetic signal. However, unlike mitochondrial genes, single-gene phylogenies have low support in haemosporidian clades that diverged recently. The H. columbae apicoplast genome suggests that the apicoplast function may be conserved across Haemosporida. This parasite could be a model to study this organelle in a non-mammalian system.


Assuntos
Apicoplastos/genética , Haemosporida/citologia , Filogenia , Plasmodium/parasitologia
14.
Ann Bot ; 127(6): 749-764, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33630993

RESUMO

BACKGROUND AND AIMS: The epidermis constitutes the outermost tissue of the plant body. Although it plays major structural, physiological and ecological roles in embryophytes, the molecular mechanisms controlling epidermal cell fate, differentiation and trichome development have been scarcely studied across angiosperms, and remain almost unexplored in floral organs. METHODS: In this study, we assess the spatio-temporal expression patterns of GL2, GL3, TTG1, TRY, MYB5, MYB6, HDG2, MYB106-like, WIN1 and RAV1-like homologues in the magnoliid Aristolochia fimbriata (Aristolochiaceae) by using comparative RNA-sequencing and in situ hybridization assays. KEY RESULTS: Genes involved in Aristolochia fimbriata trichome development vary depending on the organ where they are formed. Stem, leaf and pedicel trichomes recruit most of the transcription factors (TFs) described above. Conversely, floral trichomes only use a small subset of genes including AfimGL2, AfimRAV1-like, AfimWIN1, AfimMYB106-like and AfimHDG2. The remaining TFs, AfimTTG1, AfimGL3, AfimTRY, AfimMYB5 and AfimMYB6, are restricted to the abaxial (outer) and the adaxial (inner) pavement epidermal cells. CONCLUSIONS: We re-evaluate the core genetic network shaping trichome fate in flowers of an early-divergent angiosperm lineage and show a morphologically diverse output with a simpler genetic mechanism in place when compared to the models Arabidopsis thaliana and Cucumis sativus. In turn, our results strongly suggest that the canonical trichome gene expression appears to be more conserved in vegetative than in floral tissues across angiosperms.


Assuntos
Proteínas de Arabidopsis , Aristolochia , Aristolochiaceae , Proteínas de Arabidopsis/genética , Aristolochia/genética , Epiderme , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Tricomas/genética
15.
Am J Bot ; 108(8): 1315-1330, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34458983

RESUMO

PREMISE: Floral spurs are key innovations associated with elaborate pollination mechanisms that have evolved independently several times across angiosperms. Spur formation can shift the floral symmetry from radial to bilateral, as it is the case in Tropaeolum, the only member of the Brassicales with floral nectar spurs. The genetic mechanisms underlying both spur and bilateral symmetry in the family have not yet been investigated. METHODS: We studied flower development and morphoanatomy of Tropaeolum longifolium. We also generated a reference transcriptome and isolated all candidate genes involved in adaxial-abaxial differential growth during spur formation. Finally, we evaluated the evolution of the targeted genes across Brassicales and examined their expression in dissected floral parts. RESULTS: Five sepals initiate spirally, followed by five petals alternate to the sepals, five antesepalous stamens, three antepetalous stamens, and three carpels. Intercalary growth at the common base of sepals and petals forms a floral tube. The spur is an outgrowth from the adaxial region of the tube, lined up with the medial sepal. We identified Tropaeolum specific duplications in the TCP3/4L and STM gene lineages, which are critical for spur formation in other taxa. In addition, we found that TM6 (MADS-box), RL2 (RAD-like7), and KN2/6L2 and OSH6L (KNOX1 genes), have been lost in core Brassicales but retained in Tropaeolum. CONCLUSIONS: Three genes are pivotal during the extreme adaxial-abaxial asymmetry of the floral tube, namely, TlTCP4L2 restricted to the adaxial side where the spur is formed, and TlTCP12 and TlSTM1 to the abaxial side, lacking a spur.


Assuntos
Magnoliopsida , Tropaeolum , Flores/genética , Néctar de Plantas , Polinização
16.
Am J Bot ; 108(10): 1838-1860, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34699609

RESUMO

PREMISE: The Rubiaceae are ideal for studying the diversity of fruits that develop from flowers with inferior ovary. We aimed to identify morpho-anatomical changes during fruit development that distinguish those derived from the carpel versus the extra-carpellary tissues. In addition, we present the fruit genetic core regulatory network in selected Rubiaceae species and compare it in terms of copy number and expression patterns to model core eudicots in the Brassicaceae and the Solanaceae. METHODS: We used light microscopy to follow morphoanatomical changes in four selected species with different fruit types. We generated reference transcriptomes for seven selected Rubiaceae species and isolated homologs of major transcription factors involved in fruit development histogenesis, assessed their homology, identified conserved and new protein motifs, and evaluated their expression in three species with different fruit types. RESULTS: Our studies revealed ovary-derived pericarp tissues versus floral-cup-derived epicarp tissues. Gene evolution analyses of FRUITFULL, SHATTERPROOF, ALCATRAZ, INDEHISCENT and REPLUMLESS homologs suggest that the gene complement in Rubiaceae is simpler compared to that in Brassicaceae or Solanaceae. Expression patterns of targeted genes vary in response to the fruit type and the developmental stage evaluated. CONCLUSIONS: Morphologically similar fruits can have different anatomies as a result of convergent tissues developed from the epicarps covering the anatomical changes from the pericarps. Expression analyses suggest that the fruit patterning regulatory network established in model core eudicots cannot be extrapolated to asterids with inferior ovaries.


Assuntos
Gentianales , Rubiaceae , Anatomia Comparada , Flores/genética , Flores/metabolismo , Frutas/genética , Regulação da Expressão Gênica de Plantas , Gentianales/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rubiaceae/genética
17.
New Phytol ; 228(2): 752-769, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32491205

RESUMO

Controlled spatiotemporal cell division and expansion are responsible for floral bilateral symmetry. Genetic studies have pointed to class II TCP genes as major regulators of cell division and floral patterning in model core eudicots. Here we study their evolution in perianth-bearing Piperales and their expression in Aristolochia, a rare occurrence of bilateral perianth outside eudicots and monocots. The evolution of class II TCP genes reveals single-copy CYCLOIDEA-like genes and three paralogs of CINCINNATA (CIN) in early diverging angiosperms. All class II TCP genes have independently duplicated in Aristolochia subgenus Siphisia. Also CIN2 genes duplicated before the diversification of Saruma and Asarum. Sequence analysis shows that CIN1 and CIN3 share motifs with Cyclin proteins and CIN2 genes have lost the miRNA319a binding site. Expression analyses of all paralogs of class II TCP genes in Aristolochia fimbriata point to a role of CYC and CIN genes in maintaining differential perianth expansion during mid- and late flower developmental stages by promoting cell division in the distal and ventral portion of the limb. It is likely that class II TCP genes also contribute to cell division in the leaf, the gynoecium and the ovules in A. fimbriata.


Assuntos
Aristolochia , Magnoliopsida , Aristolochia/genética , Evolução Molecular , Flores , Filogenia
18.
J Appl Toxicol ; 40(1): 169-175, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31466122

RESUMO

The Report on Carcinogens (RoC), from the National Toxicology Program of the USA, is one of the world-leading programs for the identification and acknowledgment of substances that represent a hazard of cancer to humans. RoC covers several essential topics concerning environmental, occupational, and pharmaceutical agents that are known to be, or reasonably anticipated to be carcinogenic to humans. To promote the highest exploitation by its potential users, several RoC aspects and features were put together into one article. For doing so, a comprehensive description is provided regarding RoC history, scope, general features, listing criteria, contents, handbook, and website. Secondary and tertiary aims for this work were (a) to point out some improvement opportunities for the RoC, and (b) to discuss pending issues in regulatory science and cancer hazard assessments. In this regard, for agents classified as probably, likely, reasonably anticipated, possibly or suspected to be a human carcinogen, there is a lack of quantitative knowledge concerning the likelihood of those agents actually being carcinogenic to humans. Elucidating these probabilities is necessary, because the duration of current regulations and the arrival of new acts may depend on it. On the other hand, there is a dramatic imbalance in priorities toward carcinogens, compared with non-carcinogens, in current cancer hazard identification programs. That vision may ignore that the availability on the market of chemicals classified as probably not carcinogenic to humans can also be important for the employment, alimentation, economy, quality of life of consumers, and human health.


Assuntos
Testes de Carcinogenicidade , Carcinógenos/toxicidade , Transformação Celular Neoplásica/induzido quimicamente , Exposição Ambiental/efeitos adversos , Publicações Governamentais como Assunto , Neoplasias/induzido quimicamente , Saúde Pública , United States Public Health Service , Animais , Carcinógenos/classificação , Exposição Ambiental/legislação & jurisprudência , Regulamentação Governamental , Humanos , Formulação de Políticas , Saúde Pública/legislação & jurisprudência , Medição de Risco , Fatores de Risco , Estados Unidos , United States Public Health Service/legislação & jurisprudência
19.
Parasitol Res ; 119(9): 2935-2942, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594239

RESUMO

Cryptosporidium spp. are apicomplexan protozoa associated with chronic diarrhea in AIDS and other immunocompromised patients, and one of the commonest causes of childhood diarrhea and malnutrition, particularly in low-income settings. In Colombia, there are few molecular epidemiological studies on Cryptosporidium spp.; thereby, the transmission dynamics of this parasite in the country is poorly known. This study evaluated the diversity of Cryptosporidium at species, subtype family, and subtype level in children attending various day-care centers in Medellin, Colombia. Two hundred and ninety stool samples from children < 5 years of age were collected from April to November of 2015. All samples were processed by PCR and sequence analysis of the ssu RNA gene and the gp60 gene. An infection rate of 2.4% was observed, with only two Cryptosporidium species identified: C. hominis (6/7) and C. meleagridis (1/7). Cryptosporidium hominis isolates belonged to the subtypes IbA10G2, IaA13R6 and IaA13R7; IIIbA26G1R1 C. meleagridis subtype was also detected. There is a C. hominis predominance in the children evaluated, suggesting an important role of the anthroponotic transmission cycle in the day-care centers analyzed. Further investigation is required to determine infection sources and susceptible hosts in order to define appropriate management of cryptosporidiosis.


Assuntos
Cuidado da Criança/estatística & dados numéricos , Criptosporidiose/epidemiologia , Criptosporidiose/transmissão , Cryptosporidium/isolamento & purificação , Adolescente , Animais , Criança , Pré-Escolar , Colômbia/epidemiologia , Criptosporidiose/parasitologia , Cryptosporidium/classificação , DNA de Protozoário/genética , Diarreia/parasitologia , Fezes/parasitologia , Feminino , Genótipo , Humanos , Higiene , Masculino , Reação em Cadeia da Polimerase , Pobreza , Sulfotransferases/genética
20.
Australas J Dermatol ; 61(3): e276-e282, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31809560

RESUMO

Merkel cell carcinoma (MCC) is a rare skin tumour of neuroendocrine origin with aggressive behaviour. The aims of this study were to investigate the association of p63 + MCC with clinicopathological features and to estimate survival through a systematic review and meta-analysis. A comprehensive search of PubMed, Embase, Scopus and Virtual Health Library following the PRISMA guidelines was conducted on September 2017. DerSimonian and Lard random-effects models were used to calculate survival-weighted means and their corresponding 95% confidence intervals (CI) among studies. Five studies met our inclusion criteria after screening 77 citations and 36 full-text articles. The included studies enrolled 413 patients with MCC. We observed that p63 + MCC was significantly associated with mortality with OR 2.92 (95% CI [1.66-5.13]). The summary hazard ratio of multivariate analysis was 1.99 (95% CI [1.32-3.01]). The only clinicopathological feature associated with p63 + MCC with statistical significance was the Merkel cell polyomavirus (MCPyV) status. The presence of MCPyV was associated as a protective factor for the expression of p63 (OR 0.25, 95% CI [0.08-0.73]). These results support that p63 + MCC evaluated by immunohistochemistry has a poor outcome. Therefore, we suggest p63 to be performed when staging MCC.


Assuntos
Carcinoma de Célula de Merkel/metabolismo , Carcinoma de Célula de Merkel/patologia , Proteínas de Membrana/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Humanos , Estadiamento de Neoplasias , Taxa de Sobrevida
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