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1.
Plant Physiol ; 192(3): 2276-2289, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-36943252

RESUMO

Plants integrate environmental information into their developmental program throughout their lifetime. Light and temperature are particularly critical cues for plants to correctly time developmental transitions. Here, we investigated the role of photo-thermal cues in the regulation of the end-of-flowering developmental transition in the model plant Arabidopsis (Arabidopsis thaliana). We found that increased day length and higher temperature during flowering promote earlier inflorescence arrest by accelerating the rate at which the inflorescence meristem (IM) initiates floral primordia. Specifically, we show that plants arrest at a photo-thermal threshold and demonstrate that this photo-thermally mediated arrest is mediated by the floral integrator FLOWERING LOCUS T (FT), a known activator of flowering. FT expression increased over the duration of flowering, peaking during IM arrest, and we show that this is necessary and sufficient for photo-thermally induced arrest. Our data demonstrate the role of light and temperature, through FT, as key regulators of end-of-flowering. Overall, our results have important implications for understanding and modulating the flowering duration of crop species in changing light and temperature conditions in a warming global climate.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Meristema , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Inflorescência/fisiologia , Meristema/fisiologia
2.
J Exp Bot ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38442244

RESUMO

Many plants show strong heteroblastic changes in the shape and size of organs as they transition from juvenile to reproductive age. Most attention has been focussed on heteroblastic development on leaves, but we wanted to understand heteroblastic changes in reproductive organ size. We therefore studied the progression of reproductive development in the model plant Arabidopsis thaliana, and found strong reductions in the size of flowers, fruit, seed, and internodes during development. These did not arise from correlative inhibition by older fruits, or from changes in inflorescence meristem size, but seemed to stem from changes in the size of floral organ primordia themselves. We hypothesised that environmental conditions might influence this heteroblastic pattern and found that the ambient temperature during organ initiation strongly influences organ size. We show that this temperature-dependent heteroblasty is dependent on FLOWERING LOCUS T (FT) mediated signal integration, adding to the repertoire of developmental processes regulated by this pathway. Our results demonstrate that rising global temperatures will not just affect fertility, as is widely described, but also the size and seed number of fruits produced. However, we also show that such effects are not hard-wired, and that selective breeding for FT expression during reproductive development could mitigate such effects.

3.
Allergy ; 78(1): 141-155, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35971848

RESUMO

BACKGROUND: Asthma is a heterogeneous disease with several phenotypes, endotypes and severity degrees, in which different T-cell subpopulations are involved. These cells express specific miRNAs (i.e. inflamma-miRs) that can be released to serum in exosomes after activation and be used as biomarkers of underlying inflammation. Thus, we aim to evaluate specific T-cell miRNA signatures in serum exosomes from different subgroups of asthmatic patients. METHODS: Samples from healthy donors (N = 30) and patients (N = 119) with different asthma endotypes (T2high -Atopic/T2high -Non-atopic/T2low ) and severity degrees (mild/MA and moderate-severe/MSA) were used. Demographic, clinical, haematological and biochemical characteristics were collected. Twelve miRNAs previously associated with different Th subsets were preselected and their levels in serum exosome samples were measured using RTqPCR. RESULTS: We detected five miRNAs with high confidence in serum exosomes: miR-16-5p, miR-21-5p, miR-126-3p, miR146a-5p and miR-215-5p. All of them, except miR-16-5p were upregulated in MSA patients compared to MA. A logistic regression model including each of these miRNAs was created to discriminate both conditions, rendering a ROC curve AUC of 0.896 (0.830-0.961). miR-21-5p and miR-126-3p, both involved in Th1/Th2 differentiation, were specifically augmented in T2high -Atopic patients. Of note, all these changes were found in samples collected in autumn. On the contrary, IL-6high patients with MSA, which were more obese, older, with higher neutrophil and basophil counts and TNF levels, displayed a decrease of miR-21-5p, miR-126-3p and miR-146a-5p. CONCLUSION: Immune-related miRNAs, including miR-21-5p, miR-126-3p, miR-146a-5p and miR-215-5p, can be used as clinically relevant non-invasive biomarkers of the phenotype/endotype and severity of asthma.


Assuntos
Asma , Exossomos , MicroRNAs , Humanos , Biomarcadores , MicroRNAs/genética , Fenótipo , Asma/diagnóstico , Biomarcadores Tumorais
5.
Aging Clin Exp Res ; 35(2): 323-331, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36417136

RESUMO

OBJECTIVES: The impact of functional capacity over the entire functional continuum in older adults undergoing aortic valve replacement (AVR) has not been studied to date. This study aims to analyze 1.- the distribution of a cohort of older adults presenting severe aortic stenosis (AS) amenable to AVR in the different categories of the Functional Continuum Scale (FCS); 2.- its association with decision-making regarding valve disease; and 3.- its impact upon the one-year mortality rate of surgical (SAVR), transcatheter (TAVR) aortic valve replacement, or the decision to provide conservative management (OMT). METHODS: This prospective study included patients from the FRESAS (FRailty-Evaluation-in-Severe-Aortic-Stenosis) registry evaluated by the reference Heart-Team of a region in northern Spain. All the patients underwent comprehensive geriatric assessment. RESULTS: The study comprised 257 patients aged 84.0 ± 3.9 years. MANAGEMENT: SAVR: 25.3%, TAVR: 58.0% and OMT: 16.7%. Increased patient functional capacity was associated with an increased tendency to perform more invasive valve disease treatment. The overall one-year survival rate was 81.3%. One-year all-cause mortality: FCS-1 to FCS-2 "robust" 11.5%, FCS-3 to FCS-4 "prefrail" 14.7%, FCS-5 "frail" 19.2% and FCS-6 to FCS-8 "dependent" 45.0%; p < 0.001. Adjusted mortality analysis: FCS with HR = 1.206 [95%CI, 0.999-1.451 (p = 0.051)]; EuroSCORE-II with HR = 1.071 [95%CI, 1.006-1.161 (p = 0.033)]; and OMT with HR = 2.840 [95%CI, 1.409-5.772 (p = 0.004)] were retained in the final multivariable logistic regression model. CONCLUSIONS: In older AS patients amenable to AVR, the FCS is a useful predictive tool that may aid clinical decision-making.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Idoso , Humanos , Valva Aórtica/cirurgia , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento
6.
J Arthroplasty ; 38(8): 1429-1433, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36805120

RESUMO

BACKGROUND: While racial and ethnic disparities are well documented in access to total joint arthroplasty (TJA), little is known about the association between having limited English proficiency (LEP) and postoperative care access. This study seeks to correlate LEP status with rates of revision surgery after hip and knee arthroplasty. METHODS: This was a retrospective cohort study of patients aged ≥ 18 years who underwent either total hip or total knee arthroplasty between January 2013 and December 2021 at a single academic medical center. The predictor variable was English proficiency status, where LEP was defined as having a primary language that was not English. Multivariable regressions controlling for potential demographic and clinical confounders were used to calculate adjusted odds ratios of undergoing revision surgery within 1 and 2 years after primary arthroplasty for patients who have LEP, compared to English proficient patients. RESULTS: A total of 7,985 hip and knee arthroplasty surgeries were included in the analysis. There were 577 (7.2%) patients who were classified as having LEP. Patients who have LEP were less likely to undergo revision surgeries within 1 year (1.4% versus 3.2%, P = .01) and 2 years (1.7% versus 3.9%, P = .006) of primary TJA. Patients who have LEP had adjusted odds ratios of 0.45 (confidence interval: 0.22-0.92, P = .03) and 0.44 (confidence interval: 0.23-0.85, P = .01) of receiving revision surgery within 1 and 2 years, respectively. CONCLUSION: Patients who have LEP, compared to English proficient patients, were less likely to undergo revision surgeries at the same institution up to 2 years after hip and knee arthroplasty. These findings suggest that patients who have LEP may face barriers in accessing postoperative care.


Assuntos
Artroplastia do Joelho , Proficiência Limitada em Inglês , Humanos , Reoperação , Estudos Retrospectivos , Inquéritos e Questionários
7.
J Oral Maxillofac Surg ; 80(5): 902-912, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35182492

RESUMO

PURPOSE: An analysis was made of the association between the endoscopic findings of the sectioned root end surface and healing of the lesion 1 year after periapical surgery, although no studies appear to have analyzed them in relation to healing after periapical surgery. METHODS: A retrospective cohort study was made of patients subjected to periapical surgery between 2011 and 2019. After apicoectomy, the root end surface was examined, evaluating the number of canals, isthmuses, dentin cracks and craze lines, opaque dentin, and gaps between the filling material and the root canal wall. An analysis (using Generalized Estimating Equation models) was made of the association between the endoscopic findings and healing evaluated by von Arx and Kurt criteria and the modified PENN 3D criteria. The possible influence of patient age and gender and the type of tooth involved on healing was evaluated. RESULTS: A total of 108 patients (114 teeth and 128 roots) were subjected to periapical surgery. Two or more canals were detected in 27.3% of the roots (8.6% not subjected to orthograde filing), and isthmuses were identified in 18%, craze lines in 7%, cracks in 3.1%, opaque dentin in 69.5%, and gaps in 53.1% of the roots. The healing rate at 1 year according to the criteria of von Arx and Kurt was 95.4% versus 82.2% according to the modified PENN 3D criteria. Failure was more common in roots with cracks, although statistical significance was not reached (odds ratio [95% confidence interval]: 0.20 [0.01 to 4.04]; P = .200). The rest of the endoscopic findings as well as patient age and gender and the type of tooth did not influence healing (P > .05). CONCLUSIONS: In the present sample, no statistically significant associations were observed between the endoscopic and healing at 1 year after periapical surgery. Failure was more common in roots with cracks, however.


Assuntos
Apicectomia , Materiais Restauradores do Canal Radicular , Humanos , Estudos Retrospectivos , Materiais Restauradores do Canal Radicular/uso terapêutico , Tratamento do Canal Radicular , Cicatrização
8.
Rev Med Chil ; 150(7): 958-965, 2022 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-37906830

RESUMO

At the beginning of the COVID-19 pandemic in Chile, in March 2020, a projection indicated that a significant group of patients with pneumonia would require admission to an Intensive Care Unit and connection to a mechanical ventilator. Therefore, a paucity of these devices and other supplies was predicted. The initiative "Un respiro para Chile" brought together many people and institutions, public and private. In the course of three months, it allowed the design and building of several ventilatory assistance devices, which could be used in critically ill patients.


Assuntos
COVID-19 , Pandemias , Humanos , Chile/epidemiologia , Ventiladores Mecânicos , Unidades de Terapia Intensiva , Respiração Artificial
9.
Genome ; 64(9): 857-868, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34232087

RESUMO

The frog species Physalaemus ephippifer exists in the Amazonian region and harbors heteromorphic Z and W chromosomes. A genetic lineage closely related to this species was recognized based on its mitochondrial DNA and RADseq-style markers, but its taxonomic status is still unclear and has been referred to as Lineage 1 of "P. cuvieri". The heteromorphic sex chromosomes found in P. ephippifer are not present in this lineage and which of its chromosome pairs is homologous to the sex chromosomes of P. ephippifer remain to be elucidated as well as the role of such a karyotypic divergence in the evolution of these frogs. Here, we described a new family of repetitive DNA and used its chromosomal sites along with the markers detected by a probe constructed from the microdissected segment of the Z chromosome of P. ephippifer to infer chromosomal homology. We also analyzed an unnamed species that is considered to be the sister group of the clade composed of Lineage 1 of "P. cuvieri" and P. ephippifer. Our results suggest that complex rearrangements involving the chromosomes that were inferred to be homeologous to the sex chromosomes of P. ephippifer have occurred during the divergence of this group of frogs.


Assuntos
Anuros , Sequências Repetitivas de Ácido Nucleico , Cromossomos Sexuais , Animais , Anuros/genética , Mapeamento Cromossômico , Cariotipagem , Cromossomos Sexuais/genética
10.
Cladistics ; 37(1): 73-105, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-34478175

RESUMO

The relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecular dataset included sequences of three mitochondrial and five nuclear genes from 210 terminals, including 12 outgroup species, the two species of Xenohyla, and 93 of the 108 recognized species of Dendropsophus. The phenomic dataset includes 46 terminals, one per species (34 Dendropsophus, one Xenohyla, and 11 outgroup species). Our results corroborate the monophyly of Dendropsophini and the reciprocal monophyly of Dendropsophus and Xenohyla. Some species groups of Dendropsophus are paraphyletic (the D. microcephalus, D. minimus, and D. parviceps groups, and the D. rubicundulus clade). On the basis of our results, we recognize nine species groups; for three of them (D. leucophyllatus, D. microcephalus, and D. parviceps groups) we recognize some nominal clades to highlight specific morphology or relationships and facilitate species taxonomy. We further discuss the evolution of oviposition site selection, where our results show multiple instances of independent evolution of terrestrial egg clutches during the evolutionary history of Dendropsophus.


Assuntos
Anuros/classificação , Anuros/genética , Filogenia , Animais , Núcleo Celular/genética , Genes Mitocondriais , RNA Ribossômico 16S , Análise de Sequência de DNA
11.
J Craniofac Surg ; 32(7): 2500-2507, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34224458

RESUMO

ABSTRACT: Cerebrospinal fluid (CSF) leakage caused by skull base fracture represents high risks of bacterial meningitis, and a rate of mortality of 8.9%. Endoscopic endonasal repair of CSF leaks is quite safe and effective procedure with high rates of success. The aim of this study is to describe our technique for management of skull base CSF leaks secondary to craniofacial trauma based on the anatomic location of the leak. This is a retrospective case series of 17 patients with diagnosis of craniofacial trauma, surgically treated with sole endonasal endoscopic and combined endonasal/transcranial approaches with diagnosis of CSF leak secondary to skull base fractures. Seventeen patients met inclusion criteria for this study. Mean age was 46 years old. Most common etiology was motor vehicle. Early surgery was performed in 8 patients, and late surgery in 9 patients. The most common site of CSF leak was at ethmoid cells or at the fronto-ethmoid junction in 9 patients. Thirteen patients (76.4%) were treated only with endonasal endoscopic technique, and 4 (23.5%) with hybrid surgery, combining endonasal endoscopic and cranial bicoronal approaches with nasal and pericranial vascularized flaps, and nasal mucosal free flaps. Mean hospital stay was 23.7 days.The mean follow-up time was 25.6 months. When surgical reconstruction is indicated for CSF leaks secondary to skull base fractures, endonasal endoscopic techniques should be part of the surgical management either as a sole procedure, or in combination with classical transcranial approaches with high rates of success and low morbidity.


Assuntos
Procedimentos de Cirurgia Plástica , Ferimentos não Penetrantes , Vazamento de Líquido Cefalorraquidiano/etiologia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Endoscopia , Humanos , Pessoa de Meia-Idade , Mucosa Nasal , Estudos Retrospectivos , Base do Crânio/cirurgia
12.
Nano Lett ; 20(2): 1362-1369, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31928014

RESUMO

Three-dimensional (3D) optical microscopy can be used to understand and improve the delivery of nanomedicine. However, this approach cannot be performed for analyzing liposomes in tissues because the processing step to make tissues transparent for imaging typically removes the lipids. Here, we developed a tag, termed REMNANT, that enables 3D imaging of organic materials in biological tissues. We demonstrated the utility of this tag for the 3D mapping of liposomes in intact tissues. We also showed that the tag is able to monitor the release of entrapped therapeutic agents. We found that liposomes release their cargo >100-fold faster in tissues in vivo than in conventional in vitro assays. This allowed us to design a liposomal formulation with enhanced ability to kill tumor associated macrophages. Our development opens up new opportunities for studying the chemical properties and pharmacodynamics of administered organic materials in an intact biological environment. This approach provides insight into the in vivo behavior of degradable materials, where the newly discovered information can guide the engineering of the next generation of imaging and therapeutic agents.


Assuntos
Diagnóstico por Imagem/métodos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Animais , Humanos , Imageamento Tridimensional , Lipídeos/química , Lipossomos/química , Lipossomos/farmacologia , Camundongos , Nanomedicina , Neoplasias/patologia , Macrófagos Associados a Tumor/efeitos dos fármacos
13.
Cerebrovasc Dis ; 49(6): 625-631, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33221801

RESUMO

INTRODUCTION: Differential diagnosis between ischemic and hemorrhagic strokes in the acute stage is one of the major challenges of neurovascular research. Several biomarkers have been studied, but attempts to date have focused on determining their blood levels. Recently, cerebral lymphatic drainage toward the nostrils has been discovered, giving us the chance to study nasal exudate looking for biomarkers of neural damage. We sought to confirm whether iron levels in nasal exudate could identify the hemorrhagic nature of acute stroke. METHODS: We studied iron nasal exudate levels in 32 ischemic and 43 hemorrhagic stroke patients. All patients underwent neurological examination assessed by the National Institutes of Health Stroke Scale (NIHSS), brain computed tomography to the differential diagnosis of stroke subtype, laboratory tests, and measurement of iron levels in nasal exudate. RESULTS: The iron levels in nasal exudate were higher in hemorrhagic stroke patients. The area under the receiver operating characteristic curve for ischemic/hemorrhagic stroke discrimination was 0.896 (95% confidence interval 0.823-0.970) and cutoff point of 0.078 nmol/mg (sensitivity 93%, specificity 73%). CONCLUSIONS: Our findings suggest that iron levels in nasal exudate may be useful in the acute stage for the differential diagnosis between ischemic and hemorrhagic damage in acute stroke patients. They also open a potential field to study other biomarkers in nasal exudate in several neurological disorders. Clinical studies must be performed to confirm our results.


Assuntos
Exsudatos e Transudatos/química , Acidente Vascular Cerebral Hemorrágico/diagnóstico , Ferro/análise , AVC Isquêmico/diagnóstico , Linfa/química , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Diagnóstico Diferencial , Feminino , Acidente Vascular Cerebral Hemorrágico/metabolismo , Humanos , AVC Isquêmico/metabolismo , Masculino , Pessoa de Meia-Idade , Nariz , Valor Preditivo dos Testes , Estudo de Prova de Conceito , Estudos Prospectivos , Reprodutibilidade dos Testes
14.
Clin Chem Lab Med ; 58(5): 847-853, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-31730519

RESUMO

Background Differentiation between hemorrhagic and ischemic stroke is currently made by brain imaging or analyzing blood and cerebrospinal fluid (CSF) samples. After describing a new drainage route from brain to nasal mucosa, nasal exudate samples can be considered a new and promising source of biomarkers. Saliva can also be evaluated. Methods We determined iron in nasal exudate and saliva samples from patients of acute stroke during the first 48 h from onset. A simple, non-invasive sampling procedure was employed to obtain information from the brain. Samples were taken with a pre-weighed swab, solved in a 2% nitric acid solution and iron was measured by inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS). Results A significant difference in the dispersion of results of iron concentration for both stroke subtypes was observed in nasal exudate samples. The interquartile range was 0.608 nmol mg-1 of iron for hemorrhagic strokes and only 0.044 nmol mg-1 for ischemic strokes. In saliva samples, however, the values were 0.236 vs. 0.157 nmol mg-1. A cut-off limit of 0.102 nmol of iron per mg of nasal exudate provides a methodology with a 90% of sensitivity and a 90% of specificity. The value of the area under (AUC) the receiver operating characteristic curve (ROC) for nasal exudate samples is 0.960, considered as very good in which regards to its predictive value. Conclusions Non-invasive samples of nasal secretion have allowed obtaining, for the first time, information from the brain. Determination of iron in nasal exudate by ICP-MS allowed differentiation between ischemic and hemorrhagic strokes.


Assuntos
Exsudatos e Transudatos/química , Acidente Vascular Cerebral Hemorrágico/diagnóstico , Ferro/análise , AVC Isquêmico/diagnóstico , Mucosa Nasal/metabolismo , Espectrometria de Massas em Tandem/métodos , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biomarcadores/análise , Encéfalo/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Saliva/química , Tomografia Computadorizada por Raios X
15.
Mikrochim Acta ; 187(3): 169, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060641

RESUMO

In this work, novel silver sulphide quantum dots (Ag2S QD) are electrochemically quantified for the first time. The method is based on the electrochemical reduction of Ag+ to Ag0 at -0.3 V on screen-printed carbon electrodes (SPCEs), followed by anodic stripping voltammetric oxidation that gives a peak of currents at +0.06 V which represents the analytical signal. The optimized methodology allows the quantification of water-stabilized Ag2S QD in the range of approximately 2 × 109-2 × 1012 QD·mL-1 with a good reproducibility (RSD: 5%). Moreover, as proof-of-concept of relevant biosensing application, Ag2S QD are evaluated as tags for Escherichia coli (E. coli) bacteria determination. Bacteria tagged with QD are separated by centrifugation from the sample solution and placed on the SPCE surface for quantitative analysis. The effect of two different Ag2S QD surface coating/stabilizing agents on both the voltammetric response and the bacteria sensing is also evaluated. 3-mercaptopropionic acid (3-MPA) is studied as model of short length coating ligand with no affinity for the bacteria, while boronic acid (BA) is evaluated as longer length ligand with chemical affinity for the polysaccharides present in the peptidoglycan layer on the bacteria cells surface. The biosensing system allows to detect bacteria in the range 10-1-103 bacteria·mL-1 with a limit of detection as low as 1 bacteria·mL-1. This methodology is a promising proof-of-concept alternative to traditional laboratory-based tests, with good sensitivity and short time and low cost of analysis. Graphical abstractNovel silver sulphide quantum dots (Ag2S QD) are electrochemically quantified for the first time. Moreover, Ag2S QD are evaluated as tags for Escherichia coli bacteria determination. The effect of two different QD surface coating ligands is also evaluated.


Assuntos
Bactérias/patogenicidade , Técnicas Eletroquímicas/métodos , Pontos Quânticos/química , Compostos de Prata/química , Ligantes
16.
JAMA ; 330(9): 790-791, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37486662

RESUMO

This Arts and Medicine essay describes creation of a batik art installation titled Risktalk, illustrating trends in mentions of public health and non-health risk-related topics in popular written media from 1810 to 2009.


Assuntos
Comunicação , Medicina nas Artes , Saúde Pública , Risco , Arte , Têxteis
17.
Genet Mol Biol ; 37(3): 526-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25249775

RESUMO

Plethodontid salamanders of genus Bolitoglossa constitute the largest and most diverse group of salamanders, including around 20% of living caudate species. Recent studies have indicated the occurrence of five recognized species in the Brazilian Amazon Rainforest. We present here the first cytogenetic data of a Brazilian salamander, which may prove to be a useful by contribution to the cytotaxonomy of the genus. Specimens were collected near the "type" locality (Utinga, Belém, PA, Brazil). Chromosomal preparations from duodenal epithelial cells and testes were subjected to Giemsa staining, C-banding and DAPI/CMA3 fluorochrome staining. All specimens showed a karyotype with 13 bi-armed chromosome pairs (2n = 26). Nucleolar Organizer Regions, evidenced by CMA3, were located distally on the long arm of pair 7 (7q). DAPI+ heterochromatin was predominantly centromeric, with some small pericentromeric bands. Although the C-banding patterns of other Bolitoglossa species are so far unknown, cytogenetic studies conducted in other Plethodontid salamanders have demonstrated that pericentromeric heterochromatin is a useful cytological marker for identifying interspecific homeologies. Species diversification is usually accompanied by chromosomal changes. Therefore, the cytogenetic characterization of Bolitoglossa populations from the middle and western Brazilian Amazon Basin could identify differences which may lead to the identification of new species.

18.
Curr Biol ; 34(8): 1755-1761.e6, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38521061

RESUMO

All ∼14,000 extant ant species descended from the same common ancestor, which lived ∼140-120 million years ago (Ma).1,2 While modern ants began to diversify in the Cretaceous, recent fossil evidence has demonstrated that older lineages concomitantly occupied the same ancient ecosystems.3 These early-diverging ant lineages, or stem ants, left no modern descendants; however, they dominated the fossil record throughout the Cretaceous until their ultimate extinction sometime around the K-Pg boundary. Even as stem ant lineages appear to be diverse and abundant throughout the Cretaceous, the extent of their longevity in the fossil record and circumstances contributing to their extinction remain unknown.3 Here we report the youngest stem ants, preserved in ∼77 Ma Cretaceous amber from North Carolina, which illustrate unexpected morphological stability and lineage persistence in this enigmatic group, rivaling the longevity of contemporary ants. Through phylogenetic reconstruction and morphometric analyses, we find evidence that total taxic turnover in ants was not accompanied by a fundamental morphological shift, in contrast to other analogous stem extinctions such as theropod dinosaurs. While stem taxa showed broad morphological variation, high-density ant morphospace remained relatively constant through the last 100 million years, detailing a parallel, but temporally staggered, evolutionary history of modern and stem ants.


Assuntos
Âmbar , Formigas , Evolução Biológica , Fósseis , Filogenia , Animais , Formigas/fisiologia , Formigas/anatomia & histologia , Formigas/classificação , Fósseis/anatomia & histologia , North Carolina , Extinção Biológica
19.
Surg Neurol Int ; 15: 143, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741983

RESUMO

Background: Primary central nervous system (CNS) lymphoma is a very rare extranodal non-Hodgkin lymphoma. The bilateral pattern, as we call it "mirror type", has been identified in other CNS lesions such as gliomas, metastases, and demyelinating lesions, so the differential diagnosis includes imaging studies such as magnetic resonance imaging contrasted with spectroscopy, ruling out immunodeficiency or metastatic disease. Case Description: A 65-year-old female presented progressing headache, loss of memory and language alterations, as well as sensory alterations. Neuroimaging showed the presence of two equidistant periventricular lesions at the level of both ventricular atria, a spectroscopy study suggestive of malignancy. Serological studies showed no evidence of immunodeficiency or the presence of positive tumor markers; however, a biopsy was performed, which revealed a histopathological result of primary lymphoma of the CNS. Conclusion: In neuro-oncology, primary CNS tumors with multiple lesions are rare, even more, the "mirror type" lesions. Lymphomas are lesions that can present in different ways on imaging and clinical presentation. These tumors that present a vector effect due to their size, perilesional edema, or that lead to loss of neurological function are highly discussed in diagnostic and surgical treatment. Due to their prognosis, action on diagnosis and treatment must be taken as quickly as hospital resources allow.

20.
Sci Rep ; 14(1): 1119, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212602

RESUMO

Previous studies of DNA sequence and karyotypic data have revealed high genetic diversity in the Physalaemus cuvieri - Physalaemus ephippifer species complex-a group of small leptodactylid frogs in South America. To date, seven major genetic lineages have been recognized in this group, with species delimitation tests supporting four to seven of them as valid species. Among these, only P. ephippifer shows heteromorphic sex chromosomes, but the implications of cytogenetic divergence for the evolution of this group are unknown. We analyzed karyotypic, mitochondrial DNA, and 3RAD genomic data to characterize a putative contact zone between P. ephippifer and P. cuvieri Lineage 1, finding evidence for admixture and karyotypic evolution. We also describe preliminary evidence for admixture between two other members of this species complex-Lineage 1 and Lineage 3 of P. cuvieri. Our study sheds new light on evolutionary relationships in the P. cuvieri - P. ephippifer species complex, suggesting an important role of karyotypic divergence in its evolutionary history and underscoring the importance of hybridization as a mechanism of sex chromosome evolution in amphibians.


Assuntos
Anuros , Cromossomos Sexuais , Animais , Cariotipagem , Anuros/genética , Cariótipo , Cromossomos Sexuais/genética , América do Sul , Filogenia , Evolução Molecular
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