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1.
J Craniofac Surg ; 33(7): e708-e712, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35765135

RESUMO

OBJECTIVES: The aim of this study was to evaluate the prevalence of maxillary tuberosity fractures in an adult population and to examine the different risk factors associated with these fractures. MATERIALS AND METHODS: This is a retrospective study; data was collected from medical records of patients who underwent a non-surgical extraction of a maxillary third molar tooth between January 2017 and March 2019. All extractions were performed by 2 maxillofacial specialists. RESULTS: A total of 403 extracted maxillary third molar teeth were included in the study. Out of them 73 cases of tuberosity fractures were recorded (18.1%). No significant difference in the number of recorded fractures was found between the 2 surgeons. The mean age of patients was 32.8 ± 11.5. In the age group of 30 years and under a fractures rate of 12.1% was recorded compared to 25.0% in the age group of over 30 (P = 0.001). Divergent or extremely curved root morphology were associated with a higher risk for fractures (30.7%) compared to convergent root morphology (13.1%) ( P < 0.001). Borderline significance ( P = 0.069) was observed for extractions of teeth with caries lesions (21.9%) compared to teeth with no caries lesions (14.6%). CONCLUSIONS: The risk of developing a tuberosity fracture during an extraction of an upper wisdom tooth increases with age by 3.1% per year. Teeth with a caries lesion or teeth with divergent or extremely curved root morphology are associated with a higher risk for tuberosity fractures. Although, distoangular teeth had reduced risk of developing a tuberosity fractures. Data collected in this study may help to evaluate the risk factors associated with tuberosity fractures, and can assist in minimizing complications during extractions.


Assuntos
Cárie Dentária , Fraturas Maxilares , Adulto , Cárie Dentária/complicações , Humanos , Fraturas Maxilares/epidemiologia , Fraturas Maxilares/cirurgia , Dente Serotino/cirurgia , Prevalência , Estudos Retrospectivos , Fatores de Risco , Extração Dentária/efeitos adversos
2.
J Neurosci ; 40(35): 6722-6731, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32487696

RESUMO

Progressive changes in vocal behavior over the course of vocal imitation leaning are often attributed exclusively to developing neural circuits, but the effects of postnatal body changes remain unknown. In songbirds, the syrinx transforms song system motor commands into sound and exhibits changes during song learning. Here we test the hypothesis that the transformation from motor commands to force trajectories by syringeal muscles functionally changes over vocal development in zebra finches. Our data collected in both sexes show that, only in males, muscle speed significantly increases and that supralinear summation occurs and increases with muscle contraction speed. Furthermore, we show that previously reported submillisecond spike timing in the avian cortex can be resolved by superfast syringeal muscles and that the sensitivity to spike timing increases with speed. Because motor neuron and muscle properties are tightly linked, we make predictions on the boundaries of the yet unknown motor code that correspond well with cortical activity. Together, we show that syringeal muscles undergo essential transformations during song learning that drastically change how neural commands are translated into force profiles and thereby acoustic features. We propose that the song system motor code must compensate for these changes to achieve its acoustic targets. Our data thus support the hypothesis that the neuromuscular transformation changes over vocal development and emphasizes the need for an embodied view of song motor learning.SIGNIFICANCE STATEMENT Fine motor skill learning typically occurs in a postnatal period when the brain is learning to control a body that is changing dramatically due to growth and development. How the developing body influences motor code formation and vice versa remains largely unknown. Here we show that vocal muscles in songbirds undergo critical transformations during song learning that drastically change how neural commands are translated into force profiles and thereby acoustic features. We propose that the motor code must compensate for these changes to achieve its acoustic targets. Our data thus support the hypothesis that the neuromuscular transformation changes over vocal development and emphasizes the need for an embodied view of song motor learning.


Assuntos
Contração Muscular , Músculo Esquelético/crescimento & desenvolvimento , Junção Neuromuscular/fisiologia , Vocalização Animal , Animais , Feminino , Tentilhões , Aprendizagem , Masculino , Neurônios Motores/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Potenciais Sinápticos
3.
Mol Cell Neurosci ; 74: 96-105, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27105823

RESUMO

Mutations of the transcription factor FOXP2 cause a severe speech and language disorder. In songbirds, FoxP2 is expressed in the medium spiny neurons (MSNs) of the avian basal ganglia song nucleus, Area X, which is crucial for song learning and adult song performance. Experimental downregulation of FoxP2 in Area X affects spine formation, prevents neuronal plasticity induced by social context and impairs song learning. Direct target genes of FoxP2 relevant for song learning and song production are unknown. Here we show that a lentivirally mediated FoxP2 knockdown in Area X of zebra finches downregulates the expression of VLDLR, one of the two reelin receptors. Zebra finch FoxP2 binds to the promoter of VLDLR and activates it, establishing VLDLR as a direct FoxP2 target. Consistent with these findings, VLDLR expression is co-regulated with FoxP2 as a consequence of adult singing and during song learning. We also demonstrate that knockdown of FoxP2 affects glutamatergic transmission at the corticostriatal MSN synapse. These data raise the possibility that the regulatory relationship between FoxP2 and VLDLR guides structural plasticity towards the subset of FoxP2-positive MSNs in an activity dependent manner via the reelin pathway.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Receptores de LDL/metabolismo , Ativação Transcricional , Vocalização Animal , Animais , Gânglios da Base/metabolismo , Gânglios da Base/fisiologia , Tentilhões , Fatores de Transcrição Forkhead/genética , Aprendizagem , Masculino , N-Metilaspartato/metabolismo , Plasticidade Neuronal , Regiões Promotoras Genéticas , Ligação Proteica , Receptores de LDL/genética , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/metabolismo
4.
Appl Microbiol Biotechnol ; 99(22): 9813-24, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26216241

RESUMO

Polycyclic aromatic hydrocarbons (PAH) are toxic pollutants widely distributed in the environment due to natural and anthropogenic processes. In order to mitigate tar oil contaminations with PAH, research on improving bioremediation approaches, which are sometimes inefficient, is needed. However, the knowledge on the fate of PAH-derived carbon and the microbial degraders in particular in compost-supplemented soils is still limited. Here we show the PAH carbon turnover mass balance in microcosms with soil-compost mixtures or in farmyard fertilized soil using [(13)C6]-pyrene as a model PAH. Complete pyrene degradation of 100 mg/kg of soil was observed in all supplemented microcosms within 3 to 5 months, and the residual (13)C was mainly found as carbon converted to microbial biomass. Long-term fertilization of soil with farmyard manure resulted in pyrene removal efficiency similar to compost addition, although with a much longer lag phase, higher mineralization, and lower carbon incorporation into the biomass. Organic amendments either as long-term manure fertilization or as compost amendment thus play a key role in increasing the PAH-degrading potential of the soil microbial community. Phospholipid fatty acid stable isotope probing (PLFA-SIP) was used to trace the carbon within the microbial population and the amount of biomass formed from pyrene degradation. The results demonstrate that complex microbial degrader consortia rather than the expected single key players are responsible for PAH degradation in organic-amended soil.


Assuntos
Consórcios Microbianos , Pirenos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solo , Biomassa , Biotransformação , Isótopos de Carbono/análise , Citosol/química , Ácidos Graxos/análise , Marcação por Isótopo , Fosfolipídeos/análise
5.
Proc Biol Sci ; 281(1785): 20140460, 2014 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-24807258

RESUMO

The singing of song birds can form complex signal systems comprised of numerous subunits sung with distinct combinatorial properties that have been described as syntax-like. This complexity has inspired inquiries into similarities of bird song to human language; but the quantitative analysis and description of song sequences is a challenging task. In this study, we analysed song sequences of common nightingales (Luscinia megarhynchos) by means of a network analysis. We translated long nocturnal song sequences into networks of song types with song transitions as connectors. As network measures, we calculated shortest path length and transitivity and identified the 'small-world' character of nightingale song networks. Besides comparing network measures with conventional measures of song complexity, we also found a correlation between network measures and age of birds. Furthermore, we determined the numbers of in-coming and out-going edges of each song type, characterizing transition patterns. These transition patterns were shared across males for certain song types. Playbacks with different transition patterns provided first evidence that these patterns are responded to differently and thus play a role in singing interactions. We discuss potential functions of the network properties of song sequences in the framework of vocal leadership. Network approaches provide biologically meaningful parameters to describe the song structure of species with extremely large repertoires and complex rules of song retrieval.


Assuntos
Aves Canoras/fisiologia , Vocalização Animal , Animais , Berlim , Masculino , Redes Neurais de Computação
6.
Environ Sci Technol ; 48(15): 8717-26, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24967613

RESUMO

Metabolism of a low-solubility substrate is limited by dissolution and availability and can hardly be determined. We developed a numerical model for simultaneously calculating dissolution kinetics of such substrates and their metabolism and microbial growth (Monod kinetics with decay) and tested it with three aerobic phenanthrene (PHE) degraders: Novosphingobium pentaromativorans US6-1, Sphingomonas sp. EPA505, and Sphingobium yanoikuyae B1. PHE was present as microcrystals, providing non-limiting conditions for growth. Total PHE and protein concentration were tracked over 6-12 days. The model was fitted to the test results for the rates of dissolution, metabolism, and growth. The strains showed similar efficiency, with vmax values of 12-18 g dw g(-1) d(-1), yields of 0.21 g g(-1), maximum growth rates of 2.5-3.8 d(-1), and decay rates of 0.04-0.05 d(-1). Sensitivity analysis with the model shows that (i) retention in crystals or NAPLs or by sequestration competes with biodegradation, (ii) bacterial growth conditions (dissolution flux and resulting chemical activity of substrate) are more relevant for the final state of the system than the initial biomass, and (iii) the desorption flux regulates the turnover in the presence of solid-state, sequestered (aged), or NAPL substrate sources.


Assuntos
Modelos Biológicos , Fenantrenos/metabolismo , Sphingomonas/metabolismo , Aerobiose , Biodegradação Ambiental , Biomassa , Cinética , Solubilidade , Sphingomonas/crescimento & desenvolvimento
7.
Diagnostics (Basel) ; 14(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38472928

RESUMO

This case report details the application and outcomes of a novel therapeutic approach involving hyperthermic intraperitoneal chemotherapy (HIPEC) and hyperthermic intrathoracic chemotherapy (HITOC) in a single patient diagnosed with advanced ovarian neoplasm. The treatment protocol included pleural cytoreductive surgery (CRS) and HITOC followed by a second surgical intervention consisting of peritoneal CRS and HIPEC. HIPEC targeted the intraperitoneal space with heated chemotherapy, while HITOC extended the thermal perfusion to the thoracic cavity. The patient has shown significant progression in disease-free survival over one year and eight months of observation, demonstrating lower recurrence rates and an overall survival outcome exceeding expectations based on conventional therapy outcomes. The combined modality demonstrated a manageable toxicity profile, with no significant increase in peri- or postoperative complications observed.

8.
Nat Commun ; 14(1): 7787, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086817

RESUMO

Vocal signals, including human speech and birdsong, are produced by complicated, precisely coordinated body movements, whose execution is fitness-determining in resource competition and mate choice. While the acquisition and maintenance of motor skills generally requires practice to develop and maintain both motor circuitry and muscle performance, it is unknown whether vocal muscles, like limb muscles, exhibit exercise-induced plasticity. Here, we show that juvenile and adult zebra finches (Taeniopygia castanotis) require daily vocal exercise to first gain and subsequently maintain peak vocal muscle performance. Experimentally preventing male birds from singing alters both vocal muscle physiology and vocal performance within days. Furthermore, we find females prefer song of vocally exercised males in choice experiments. Vocal output thus contains information on recent exercise status, and acts as an honest indicator of past exercise investment in songbirds, and possibly in all vocalising vertebrates.


Assuntos
Tentilhões , Canto , Vocalização Animal , Animais , Feminino , Masculino , Tentilhões/fisiologia , Canto/fisiologia , Aves Canoras/fisiologia , Vocalização Animal/fisiologia
9.
bioRxiv ; 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36865130

RESUMO

Vocal signals mediate much of human and non-human communication. Key performance traits - such as repertoire size, speed and accuracy of delivery - affect communication efficacy in fitness-decisive contexts such as mate choice and resource competition 1 . Specialized fast vocal muscles 2,3 are central to accurate sound production 4 , but it is unknown whether vocal, like limb muscles 5,6 , need exercise to gain and maintain peak performance 7,8 . Here, we show that for song development in juvenile songbirds, the closest analogue to human speech acquisition 9 , regular vocal muscle exercise is crucial to achieve adult peak muscle performance. Furthermore, adult vocal muscle performance reduces within two days of abolishing exercise, leading to downregulation of critical proteins transforming fast to slower muscle fibre types. Daily vocal exercise is thus required to both gain and maintain peak vocal muscle performance, and if absent changes vocal output. We show that conspecifics can detect these acoustic changes and females prefer the song of exercised males. Song thus contains information on recent exercise status of the sender. Daily investment in vocal exercise to maintain peak performance is an unrecognized cost of singing and could explain why many birds sing daily even under adverse conditions 10 . Because neural regulation of syringeal and laryngeal muscle plasticity is equivalent, vocal output may reflect recent exercise status in all vocalizing vertebrates.

10.
Diagnostics (Basel) ; 13(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37238242

RESUMO

(1) Background: We aim to present our experience with resection of the inferior vena cava (IVC) without reconstruction in two patients diagnosed with renal tumors. (2) Case Report: The first case was diagnosed with right renal vein sarcoma and the second case was diagnosed with clear cell renal carcinoma; both presented signs of invasion and thrombosis of the IVC at infrarenal and cruoric levels, along with the development of collateral circulation with the help of the paravertebral plexus. In both patients, en bloc right nephrectomy was performed along with the resection of the thrombosed IVC without further reconstruction. In the case of the patient with right vein sarcoma, preservation of the left renal and caval intrahepatic vein was possible, whilst in the second case diagnosed with clear cell renal carcinoma, the associated left renal thrombosis also enforced the resection of the left renal vein. (3) Discussion: Postoperative evolution was favorable in both cases and did not exhibit major complications. Antibiotic therapy, analgesics, and anticoagulant medication were administered at therapeutic doses after surgery in both cases. The histopathological examination of the surgical specimen confirmed the diagnoses of renal vein sarcoma in the first case and clear cell renal carcinoma in the second case. Surgical treatment and adjuvant chemotherapy prolonged survival for two years for the first case and for two months, up until this moment, for the second case. The survival of clear cell renal carcinoma is currently at two months. (4) Conclusions: The resection of the inferior vena cava, without subsequent reconstruction in cases presenting diffused distal thrombosis, can represent an alternative to IVC reconstruction, which might lead to a major ulterior risk of thrombosis. In some cases, this can result in long-term survival.

11.
Sci Rep ; 12(1): 13414, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927295

RESUMO

Interactive biorobotics provides unique experimental potential to study the mechanisms underlying social communication but is limited by our ability to build expressive robots that exhibit the complex behaviours of birds and small mammals. An alternative to physical robots is to use virtual environments. Here, we designed and built a modular, audio-visual 2D virtual environment that allows multi-modal, multi-agent interaction to study mechanisms underlying social communication. The strength of the system is an implementation based on event processing that allows for complex computation. We tested this system in songbirds, which provide an exceptionally powerful and tractable model system to study social communication. We show that pair-bonded zebra finches (Taeniopygia guttata) communicating through the virtual environment exhibit normal call timing behaviour, males sing female directed song and both males and females display high-intensity courtship behaviours to their mates. These results suggest that the environment provided is sufficiently natural to elicit these behavioral responses. Furthermore, as an example of complex behavioral annotation, we developed a fully unsupervised song motif detector and used it to manipulate the virtual social environment of male zebra finches based on the number of motifs sung. Our virtual environment represents a first step in real-time automatic behaviour annotation and animal-computer interaction using higher level behaviours such as song. Our unsupervised acoustic analysis eliminates the need for annotated training data thus reducing labour investment and experimenter bias.


Assuntos
Tentilhões , Canto , Aves Canoras , Animais , Feminino , Tentilhões/fisiologia , Masculino , Mamíferos , Meio Social , Aves Canoras/fisiologia , Vocalização Animal/fisiologia
12.
Sci Rep ; 11(1): 6469, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33742101

RESUMO

Vocal behavior can be dramatically changed by both neural circuit development and postnatal maturation of the body. During song learning in songbirds, both the song system and syringeal muscles are functionally changing, but it is unknown if maturation of sound generators within the syrinx contributes to vocal development. Here we densely sample the respiratory pressure control space of the zebra finch syrinx in vitro. We show that the syrinx produces sound very efficiently and that key acoustic parameters, minimal fundamental frequency, entropy and source level, do not change over development in both sexes. Thus, our data suggest that the observed acoustic changes in vocal development must be attributed to changes in the motor control pathway, from song system circuitry to muscle force, and not by material property changes in the avian analog of the vocal folds. We propose that in songbirds, muscle use and training driven by the sexually dimorphic song system are the crucial drivers that lead to sexual dimorphism of the syringeal skeleton and musculature. The size and properties of the instrument are thus not changing, while its player is.


Assuntos
Tentilhões/fisiologia , Prega Vocal/crescimento & desenvolvimento , Vocalização Animal , Animais , Feminino , Tentilhões/crescimento & desenvolvimento , Masculino , Desenvolvimento Muscular , Maturidade Sexual , Prega Vocal/fisiologia
13.
Curr Biol ; 31(14): 3115-3124.e5, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34089645

RESUMO

The motor control resolution of any animal behavior is limited to the minimal force step available when activating muscles, which is set by the number and size distribution of motor units (MUs) and muscle-specific force. Birdsong is an excellent model system for understanding acquisition and maintenance of complex fine motor skills, but we know surprisingly little about how the motor pool controlling the syrinx is organized and how MU recruitment drives changes in vocal output. Here we developed an experimental paradigm to measure MU size distribution using spatiotemporal imaging of intracellular calcium concentration in cross-sections of living intact syrinx muscles. We combined these measurements with muscle stress and an in vitro syrinx preparation to determine the control resolution of fundamental frequency (fo), a key vocal parameter, in zebra finches. We show that syringeal muscles have extremely small MUs, with 40%-50% innervating ≤3 and 13%-17% innervating a single muscle fiber. Combined with the lowest specific stress (5 mN/mm2) known to skeletal vertebrate muscle, small force steps by the major fo controlling muscle provide control of 50-mHz to 7.3-Hz steps per MU. We show that the song system has the highest motor control resolution possible in the vertebrate nervous system and suggest this evolved due to strong selection on fine gradation of vocal output. Furthermore, we propose that high-resolution motor control was a key feature contributing to the radiation of songbirds that allowed diversification of song and speciation by vocal space expansion.


Assuntos
Músculos Laríngeos/inervação , Fenômenos Fisiológicos do Sistema Nervoso , Aves Canoras , Vocalização Animal/fisiologia , Animais
14.
Proc Biol Sci ; 277(1686): 1333-6, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20053652

RESUMO

While all members of the Orchidaceae are fully dependent on mycorrhizal fungi during their achlorophyllous juvenile stages, mature plants may remain fully myco-heterotrophic, become fully autotrophic or develop a nutritional mode where the carbon gain through photosynthesis is complemented by organic carbon from fungal partners. This so-called partial myco-heterotrophy is intriguingly complex. Current knowledge indicates a large range in the proportion of fungus-derived carbon between and within partially myco-heterotrophic plant species. However, the driving factors for this variation are so far mostly unknown. Here we show for two green species of the orchid genus Cephalanthera that light availability is the major determinant of the degree of myco-heterotrophy. Using leaf stable isotope natural abundance analysis together with time-integrated microscale light climate monitoring we could demonstrate that there is a sensitive reaction to varying light availability within forests. Low light levels result in strong myco-heterotrophy while higher irradiances successively drive the orchids towards autotrophy. Our results demonstrate that partial myco-heterotrophy in these species is not a static nutritional mode but a flexible mechanism driven by light availability which allows a balanced usage of carbon resources available in nature.


Assuntos
Isótopos de Carbono/metabolismo , Fungos/metabolismo , Processos Heterotróficos , Luz , Orchidaceae , Processos Autotróficos , Micorrizas , Orchidaceae/metabolismo , Orchidaceae/microbiologia , Fotossíntese , Folhas de Planta/microbiologia , Especificidade da Espécie
15.
Am J Otolaryngol ; 30(5): 356-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19720259

RESUMO

Bio-alcamid is one of the newest agents on the market for soft tissue augmentation. Seven studies were documented in the medical literature that examined the safety of Bio-alcamid (Polymekon, Brindisy, Italy); all reported no cases of tissue migration, foreign body granulomas, allergenicity, or interference with the control of cell proliferation. On 2 separate occasions, a woman who had recently undergone lip augmentation presented at our hospital with submucosal nodules of the lip. Histologic examination revealed multiple foreign body-type granulomas composed of giant cells, epithelioid cells, and chronic inflammation of the lip. Efforts to produce a cosmetic material that fulfills all the criteria as an "ideal" agent has not yet been found because all injectable foreign agents have the potential to induce adverse reactions. Caution must be exercised in all cases and the risks explained to the patient before its use.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Técnicas Cosméticas/efeitos adversos , Granuloma de Corpo Estranho/induzido quimicamente , Lábio/cirurgia , Resinas Acrílicas , Adulto , Feminino , Granuloma de Corpo Estranho/etiologia , Granuloma de Corpo Estranho/cirurgia , Humanos , Injeções Subcutâneas/efeitos adversos , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
16.
Cancer Lett ; 253(2): 282-90, 2007 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-17386971

RESUMO

Alteration in DNA content is an early event in oral carcinogenesis. We have examined oral brush samples to detect non-diploid cells (NDC) using simultaneous morphological and cytogenetic analysis. The study included 8 oral squamous cell carcinomas (OSCC), 22 premalignant lesions (OPLs), and 25 control individuals. Slides stained with Giemsa followed by FISH using chromosome 2 centromeric DNA probe, were scanned and fluorescent signals were simultaneously analyzed in parallel with the morphology. The proportion of NDC increased with the severity of the diagnosis. In two control subjects, 1-1.5% of the examined cells were NDC. Over 2% NDC were present in all OSCC cases and in 11 of the OPLs, of which, in 8 the histologic diagnosis was either epithelial hyperplasia or mild dysplasia. A significant number of NDC had normal morphology when cytomorphology and FISH were compared. Two patients with OPLs developed OSCC these patients had a significant proportion of NDC. We suggest that the combined morphological and cytogenetic analysis of cells collected by a non-invasive brush sampling can enhance early detection of potentially malignant cells.


Assuntos
Análise Citogenética/métodos , Hibridização in Situ Fluorescente/métodos , Neoplasias Bucais/diagnóstico , Neoplasias de Células Escamosas/diagnóstico , Lesões Pré-Cancerosas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 2/genética , DNA de Neoplasias/análise , Diploide , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Neoplasias de Células Escamosas/genética , Neoplasias de Células Escamosas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia
17.
AMB Express ; 7(1): 7, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28050848

RESUMO

Polycyclic aromatic hydrocarbons are distributed ubiquitously in the environment and form metabolites toxic to most organisms. Organic amendment of PAH contaminated soil with compost and farmyard manure has proven to be efficient for PAH bioremediation mediated by native microorganisms, even though information on the identity of PAH degraders in organic-amended soil is still scarce. Here we provide molecular insight into the bacterial communities in soil amended with compost or farmyard manure for which the degradation mass balances of 13C-labeled pyrene have been recently published and assess the relevant bacterial genera capable of degrading pyrene as a model PAH. We performed statistical analyses of bacterial genera abundance data based on total DNA and RNA (for comparison) extracted from the soil samples. The results revealed complex pyrene degrading communities with low abundance of individual degraders instead of a limited number of abundant key players. The bacterial degrader communities of the soil-compost mixture and soil fertilized with farmyard manure differed considerably in composition albeit showing similar degradation kinetics. Additional analyses were carried out on enrichment cultures and enabled the reconstruction of several nearly complete genomes, thus allowing to link microcosm and enrichment experiments. However, pyrene mineralizing bacteria enriched from the compost or unfertilized soil-compost samples did not dominate pyrene degradation in the soils. Based on the present findings, evaluations of PAH degrading microorganisms in complex soil mixtures with high organic matter content should not target abundant key degrading species, since the specific degraders may be highly diverse, of low abundance, and masked by high bacterial background.

18.
Elife ; 62017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29165242

RESUMO

Superfast muscles (SFMs) are extremely fast synchronous muscles capable of contraction rates up to 250 Hz, enabling precise motor execution at the millisecond time scale. SFM phenotypes have been discovered in most major vertebrate lineages, but it remains unknown whether all SFMs share excitation-contraction coupling pathway adaptations for speed, and if SFMs arose once, or from independent evolutionary events. Here, we demonstrate that to achieve rapid actomyosin crossbridge kinetics bat and songbird SFM express myosin heavy chain genes that are evolutionarily and ontologically distinct. Furthermore, we show that all known SFMs share multiple functional adaptations that minimize excitation-contraction coupling transduction times. Our results suggest that SFM evolved independently in sound-producing organs in ray-finned fish, birds, and mammals, and that SFM phenotypes operate at a maximum operational speed set by fundamental constraints in synchronous muscle. Consequentially, these constraints set a fundamental limit to the maximum speed of fine motor control.


Assuntos
Contração Muscular , Músculos/fisiologia , Actomiosina/metabolismo , Animais , Evolução Biológica , Quirópteros , Aves Canoras
19.
J Hazard Mater ; 306: 105-114, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26705887

RESUMO

Many attempts for bioremediation of polycyclic aromatic hydrocarbon (PAH) contaminated sites failed in the past, but the reasons for this failure are not well understood. Here we apply and improve a model for integrated assessment of mass transfer, biodegradation and residual concentrations for predicting the success of remediation actions. First, we provide growth parameters for Mycobacterium rutilum and Mycobacterium pallens growing on phenanthrene (PHE) or pyrene (PYR) degraded the PAH completely at all investigated concentrations. Maximum metabolic rates vmax and growth rates µ were similar for the substrates PHE and PYR and for both strains. The investigated Mycobacterium species were not superior in PHE degradation to strains investigated earlier with this method. Real-world degradation scenario simulations including diffusive flux to the microbial cells indicate: that (i) bioaugmentation only has a small, short-lived effect; (ii) Increasing sorption shifts the remaining PAH to the adsorbed/sequestered PAH pool; (iii) mobilizing by solvents or surfactants resulted in a significant decrease of the sequestered PAH, and (iv) co-metabolization e.g. by compost addition can contribute significantly to the reduction of PAH, because active biomass is maintained at a high level by the compost. The model therefore is a valuable contribution to the assessment of potential remediation action at PAH-polluted sites.


Assuntos
Modelos Teóricos , Mycobacterium/metabolismo , Fenantrenos/metabolismo , Pirenos/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Interações Hidrofóbicas e Hidrofílicas , Solo
20.
Curr Opin Neurobiol ; 28: 86-93, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25048597

RESUMO

Humans with mutations in the transcription factor FOXP2 display a severe speech disorder. Songbirds are a powerful model system to study FoxP2. Like humans, songbirds communicate via vocalizations that are imitatively learned during critical periods and this learning is influenced by social factors and relies on functionally lateralized neural circuits. During the past five years significant progress has been made moving from a descriptive to a more mechanistic understanding of how FoxP2 functions in songbirds. Current evidence from molecular and electrophysiological studies indicates that FoxP2 is important for shaping synaptic plasticity of specific neuron populations. One future goal will be to identify the transcriptional regulation orchestrated by FoxP2 and its associated molecular network that brings about these physiological effects. This will be key to further unravel how FoxP2 influences synaptic function and thereby contributes to auditory guided vocal motor behavior in the songbird model.


Assuntos
Encéfalo/metabolismo , Fatores de Transcrição Forkhead/fisiologia , Aves Canoras/metabolismo , Vocalização Animal/fisiologia , Animais
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