Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 437
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 163(3): 594-606, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26478181

RESUMO

Interacting proteins typically coevolve, and the identification of coevolving amino acids can pinpoint residues required for interaction specificity. This approach often assumes that an interface-disrupting mutation in one protein drives selection of a compensatory mutation in its partner during evolution. However, this model requires a non-functional intermediate state prior to the compensatory change. Alternatively, a mutation in one protein could first broaden its specificity, allowing changes in its partner, followed by a specificity-restricting mutation. Using bacterial toxin-antitoxin systems, we demonstrate the plausibility of this second, promiscuity-based model. By screening large libraries of interface mutants, we show that toxins and antitoxins with high specificity are frequently connected in sequence space to more promiscuous variants that can serve as intermediates during a reprogramming of interaction specificity. We propose that the abundance of promiscuous variants promotes the expansion and diversification of toxin-antitoxin systems and other paralogous protein families during evolution.


Assuntos
Evolução Molecular , Mesorhizobium/metabolismo , Mapas de Interação de Proteínas , Sequência de Aminoácidos , Antitoxinas/química , Antitoxinas/metabolismo , Bactérias/química , Bactérias/classificação , Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Modelos Moleculares , Dados de Sequência Molecular
2.
Cell ; 150(1): 222-32, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-22770222

RESUMO

Orthologous proteins often harbor numerous substitutions, but whether these differences result from neutral or adaptive processes is usually unclear. To tackle this challenge, we examined the divergent evolution of a model bacterial signaling pathway comprising the kinase PhoR and its cognate substrate PhoB. We show that the specificity-determining residues of these proteins are typically under purifying selection but have, in α-proteobacteria, undergone a burst of diversification followed by extended stasis. By reversing mutations that accumulated in an α-proteobacterial PhoR, we demonstrate that these substitutions were adaptive, enabling PhoR to avoid crosstalk with a paralogous pathway that arose specifically in α-proteobacteria. Our findings demonstrate that duplication and the subsequent need to avoid crosstalk strongly influence signaling protein evolution. These results provide a concrete example of how system-wide insulation can be achieved postduplication through a surprisingly limited number of mutations. Our work may help explain the apparent ease with which paralogous protein families expanded in all organisms.


Assuntos
Alphaproteobacteria/genética , Alphaproteobacteria/metabolismo , Proteínas de Bactérias/genética , Evolução Molecular , Mutação , Transdução de Sinais , Filogenia , Seleção Genética
3.
Cell ; 133(6): 1043-54, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18555780

RESUMO

Two-component signal transduction systems are the predominant means by which bacteria sense and respond to environmental stimuli. Bacteria often employ tens or hundreds of these paralogous signaling systems, comprised of histidine kinases (HKs) and their cognate response regulators (RRs). Faithful transmission of information through these signaling pathways and avoidance of detrimental crosstalk demand exquisite specificity of HK-RR interactions. To identify the determinants of two-component signaling specificity, we examined patterns of amino acid coevolution in large, multiple sequence alignments of cognate kinase-regulator pairs. Guided by these results, we demonstrate that a subset of the coevolving residues is sufficient, when mutated, to completely switch the substrate specificity of the kinase EnvZ. Our results shed light on the basis of molecular discrimination in two-component signaling pathways, provide a general approach for the rational rewiring of these pathways, and suggest that analyses of coevolution may facilitate the reprogramming of other signaling systems and protein-protein interactions.


Assuntos
Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Engenharia de Proteínas , Transdução de Sinais , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Caulobacter crescentus/enzimologia , Caulobacter crescentus/metabolismo , Escherichia coli/enzimologia , Proteínas de Escherichia coli/química , Genes Reguladores , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multienzimáticos/química , Mutagênese , Fosforilação , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Especificidade por Substrato , Transativadores/química , Transativadores/metabolismo
4.
Khirurgiia (Mosk) ; (2): 59-71, 2023.
Artigo em Russo | MEDLINE | ID: mdl-36748871

RESUMO

OBJECTIVE: To provide 'in use' clinical data to support exudate management in patients with moderately to highly exuding wounds with bordered superabsorbent wound dressing with a silicone adhesive interface Zetuvit Plus Silicone Border (Paul Hartmann Ltd., Germany). MATERIALS AND METHODS: This study was an open-labelled non-comparative study. Patients included in the study were selected by the clinical investigator(s) according to whether the patient required a dressing for the management of moderately to highly exuding wounds such as pressure ulcers, diabetic foot ulcers, venous leg ulcer and arterial ulcers The patients were treated with A superabsorbent sterile wound dressing with bordered superabsorbent wound dressing with a silicone adhesive interface Zetuvit Plus Silicone Border (Paul Hartmann Ltd., Germany). RESULTS: The Zetuvit Plus Silicone Border dressing had met the clinical objectives relating to exudate management, affirmed by the health professionals with a yes response in 94% of cases. Additionally, the health professionals rated the handling of exudate as excellent/good (78%) and most (80%) reported that they would use the superabsorbent wound dressing with a silicone adhesive interface again. Allied to this was the fact that the dressing improved the wound edge and periwound skin conditions (29% and 36% of patients, respectively). The dressing retained its position in 72% of patients. For wear time, the largest proportion of dressing changes, both pre-study and during the evaluation period, was every third day (45% and 44%, respectively). But there was a shift to extended wear time with use of the superabsorbent wound dressing with a silicone adhesive interface with 72% of patients' dressing changes being every third day or longer. CONCLUSION: The superabsorbent silicone border dressing was successful in managing wound exudate in moderately to highly exuding wounds and consequently this had a beneficial impact on the wound edge and periwound skin. Overall, there was a positive effect on wound bed preparation and in turn the healing response was progressive.


Assuntos
Cimentos de Resina , Úlcera Varicosa , Humanos , Bandagens , Úlcera Varicosa/terapia , Cicatrização , Silicones
5.
Pain Med ; 23(Suppl 2): S2-S13, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35856330

RESUMO

OBJECTIVE: Multiple studies have demonstrated the safety and effectiveness of basivertebral nerve radiofrequency ablation (BVN RFA) for improving low back pain related to the vertebral endplate. However, the influence of patient demographic and clinical characteristics on treatment outcome is unknown. DESIGN: Pooled cohort study of three clinical trials of patients with vertebral endplate pain identified by Type 1 and/or Type 2 Modic changes and a correlating presentation of anterior spinal element pain. SETTING: Thirty-three global study centers. SUBJECTS: Patients (n = 296) successfully treated with BVN RFA. METHODS: Participant demographic and clinical characteristics were analyzed with stepwise logistic regression to identify predictors of treatment success. Three definitions of treatment success were defined: 1) ≥50% visual analog scale pain improvement, 2) ≥15-point Oswestry Disability Index (ODI) improvement, and 3) ≥50% visual analog scale or ≥15-point ODI improvement from baseline. RESULTS: Low back pain of ≥5 years' duration and higher ODI scores at baseline increased the odds of treatment success, whereas baseline opioid use and higher Beck Depression Inventory scores reduced these odds. However, the three regression models demonstrated receiver-operating characteristics of 62-70% areas under the curve, and thus, limited predictive capacity. CONCLUSIONS: This analysis identified no demographic or clinical characteristic that meaningfully increased or reduced the odds of treatment success from BVN RFA. On the basis of these findings and the high response rates from the three analyzed trials, we recommend the use of objective imaging biomarkers (Type 1 and/or 2 Modic changes) and a correlating presentation of anterior spinal element pain to determine optimal candidacy for BVN RFA.


Assuntos
Ablação por Cateter , Dor Lombar , Ablação por Cateter/métodos , Ensaios Clínicos como Assunto , Estudos de Coortes , Humanos , Dor Lombar/cirurgia , Vértebras Lombares/cirurgia , Estudos Prospectivos , Resultado do Tratamento
6.
J Shoulder Elbow Surg ; 29(7): e279-e286, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32088074

RESUMO

BACKGROUND: Total shoulder arthroplasty (TSA) with an anatomic or reverse prosthesis is a commonly used and successful treatment option for many degenerative shoulder conditions. There is an increasing trend toward fellowship training and subspecialization in newly trained orthopedic surgeons. The literature also suggests that subspecialization and high volume are associated with better clinical outcomes. The purpose of this study was to evaluate the effects of fellowship training on the trends and outcomes of TSA in board-eligible orthopedic surgeons. METHODS: The American Board of Orthopaedic Surgery database was used to identify primary TSA cases performed for osteoarthrosis submitted by American Board of Orthopaedic Surgery Part II Board Certification candidates. Candidates were grouped based on fellowship training and subspecialty examination being taken. Groups were analyzed with analysis of variance and Bonferroni post hoc analysis to evaluate significant differences between groups for a number of candidates, cases per candidate, and patient age/sex. Differences in complications, reoperations, and readmissions were statistically evaluated with χ2 tests and multivariate logistic regression analysis. RESULTS: From 2010 to 2017, 854 candidates performed at least 1 primary TSA (anatomic or reverse) after a diagnosis of osteoarthritis and 2720 submitted cases met inclusion criteria. Candidates completing a Shoulder fellowship performed significantly more TSAs per candidate compared with all other groups (Shoulder = 8.0 ± 6.2, Sports Medicine = 2.4 ± 2.1, Hand and Upper Extremity = 2.9 ± 2.9, General Orthopedics = 2.4 ± 2.3, P < .001). The Shoulder fellowship group had significantly lower complication rates (17.9%) as compared with the Sports Medicine fellowship (23.7%, P = .008) and Hand and Upper Extremity fellowship (25.0%, P = .008) groups. CONCLUSIONS: Shoulder fellowship-trained surgeons performed significantly more TSAs per year than other groups, with a lower complication rate when compared with other fellowship-trained candidates. Fellowship type had no effect on reoperation or readmission rates.


Assuntos
Artroplastia do Ombro/efeitos adversos , Bolsas de Estudo , Ortopedia/educação , Osteoartrite/cirurgia , Idoso , Certificação , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico , Osteoartrite/etiologia , Reoperação , Estados Unidos
7.
Int Orthop ; 43(4): 797-805, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30116867

RESUMO

Ossification of the posterior longitudinal ligament (OPLL) is a rare pathologic process of lamellar bone deposition that can result in spinal cord compression. While multiple genetic and environmental factors have been related to the development of OPLL, the pathophysiology remains poorly understood. Asymptomatic patients may be managed conservatively and patients with radiculopathy or myelopathy should be considered for surgical decompression. Multiple studies have demonstrated the morphology and size of the OPLL as well as the cervical alignment have significant implications for the appropriate surgical approach and technique. In this review, we aim to address all the available literature on the etiology, history, presentation, and management of OPLL in an effort to better understand OPLL and give our recommendations for the treatment of patients presenting with OPLL.


Assuntos
Descompressão Cirúrgica , Ossificação do Ligamento Longitudinal Posterior , Osteogênese , Compressão da Medula Espinal , Idoso , Vértebras Cervicais/cirurgia , Descompressão Cirúrgica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação do Ligamento Longitudinal Posterior/diagnóstico , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Radiculopatia/cirurgia , Compressão da Medula Espinal/cirurgia , Doenças da Medula Espinal/cirurgia
8.
Mol Cell ; 39(3): 455-67, 2010 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-20598601

RESUMO

Progression through the Caulobacter cell cycle is driven by the master regulator CtrA, an essential two-component signaling protein that regulates the expression of nearly 100 genes. CtrA is abundant throughout the cell cycle except immediately prior to DNA replication. However, the expression of CtrA-activated genes is generally restricted to S phase. We identify the conserved protein SciP (small CtrA inhibitory protein) and show that it accumulates during G1, where it inhibits CtrA from activating target genes. The depletion of SciP from G1 cells leads to the inappropriate induction of CtrA-activated genes and, consequently, a disruption of the cell cycle. Conversely, the ectopic synthesis of SciP is sufficient to inhibit CtrA-dependent transcription, also disrupting the cell cycle. SciP binds directly to CtrA without affecting stability or phosphorylation; instead, SciP likely prevents CtrA from recruiting RNA polymerase. CtrA is thus tightly regulated by a protein-protein interaction which is critical to cell-cycle progression.


Assuntos
Proteínas de Bactérias/metabolismo , Caulobacter crescentus/metabolismo , Proteínas de Ligação a DNA/metabolismo , Genes Bacterianos , Fatores de Transcrição/metabolismo , Transcrição Gênica/fisiologia , Proteínas de Bactérias/genética , Caulobacter crescentus/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética
9.
Ergonomics ; 61(1): 134-147, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28679345

RESUMO

Experts in traumatic brain injury (TBI) rehabilitation recently proposed the framing of TBI as a chronic disease rather than a discrete event. Within the framework of the Chronic Care Model (CCM), a systematic comparison of three diseases - cancer survivorship, diabetes management and TBI chronic care - was conducted regarding chronic needs and the management of those needs. In addition, comparisons of these conditions require comparative evaluations of disease management characteristics and the survivor concept. The analysis found diabetes is more established within the CCM, where care is integrated across specialists and primary care providers. No single comparison provides a full analogue for understanding the chronic care health delivery system for TBI, indicating the need for a separate model to address needs and resources for TBI survivors. The findings from this research can provide practitioners with a context to develop a robust continued care health system for TBI. Practitioner Summary: We examine development of a chronic care system for traumatic brain injury. We conducted a systematic comparison of Chronic Care Model elements of decision and information support. Development of capabilities using a benchmark of diabetes care, with additional insights from cancer care, provides insights for implementing TBI chronic care systems.


Assuntos
Lesões Encefálicas Traumáticas/reabilitação , Doença Crônica/reabilitação , Atenção à Saúde/métodos , Gerenciamento Clínico , Diabetes Mellitus/reabilitação , Humanos , Assistência de Longa Duração/métodos , Neoplasias/reabilitação
10.
Ergonomics ; 61(1): 69-81, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28682155

RESUMO

As the expansion and utilisation of community pharmacy systems increases, so does the risk for an adverse drug event to occur. In attempts to mitigate this risk, many community pharmacies implement health information technology (IT); however, there are challenges in integrating the wider systems components necessary for a successful implementation with minimal unintended consequences. The purpose of this paper is to introduce a Community Health Integration through Pharmacy Process and Ergonomics Redesign (CHIPPER) framework, which explores the multiple angles of health IT integration to support medication delivery processes in community pharmacy systems. Specifically, CHIPPER identifies the information flows that occur between different parts of the system (initiation, upstream, midstream and downstream) with varying end-users and tasks related to medication delivery processes. In addition to the justification and presentation of the CHIPPER model, this paper reviews several broad applications for CHIPPER and presents two example studies that demonstrate the CHIPPER framework. Practitioner Summary: Most medication delivery in the US occurs through outpatient-based community pharmacy practice. Community pharmacies are challenged by inconsistent and incomplete information flow and technology integration between providers, pharmacy practitioners and patients. This paper presents a framework for improved healthcare systems engineering analysis of pharmacy practice, with case study examples.


Assuntos
Serviços Comunitários de Farmácia/organização & administração , Ergonomia/métodos , Sistemas de Informação em Saúde/organização & administração , Gestão de Riscos/organização & administração , Integração de Sistemas , Humanos , Erros de Medicação/prevenção & controle , Farmácias/organização & administração , Gestão de Riscos/métodos
11.
PLoS Biol ; 12(10): e1001977, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25350732

RESUMO

Cells must coordinate DNA replication with cell division, especially during episodes of DNA damage. The paradigm for cell division control following DNA damage in bacteria involves the SOS response where cleavage of the transcriptional repressor LexA induces a division inhibitor. However, in Caulobacter crescentus, cells lacking the primary SOS-regulated inhibitor, sidA, can often still delay division post-damage. Here we identify didA, a second cell division inhibitor that is induced by DNA damage, but in an SOS-independent manner. Together, DidA and SidA inhibit division, such that cells lacking both inhibitors divide prematurely following DNA damage, with lethal consequences. We show that DidA does not disrupt assembly of the division machinery and instead binds the essential division protein FtsN to block cytokinesis. Intriguingly, mutations in FtsW and FtsI, which drive the synthesis of septal cell wall material, can suppress the activity of both SidA and DidA, likely by causing the FtsW/I/N complex to hyperactively initiate cell division. Finally, we identify a transcription factor, DriD, that drives the SOS-independent transcription of didA following DNA damage.


Assuntos
Proteínas de Bactérias/metabolismo , Caulobacter crescentus/fisiologia , Divisão Celular , Dano ao DNA , Proteínas de Membrana/metabolismo , Proteínas de Bactérias/genética , Pontos de Checagem do Ciclo Celular , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Supressão Genética , Fatores de Transcrição/metabolismo
12.
J Wound Care ; 26(2): 58-63, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28182518

RESUMO

OBJECTIVE: The aim of this evaluation is to assess the effects of a wound healing gel in a wounds of different aetiologies. METHOD: Data was recorded on the wound surface area, tissue type, and patient level of wound pain at baseline (0) and at weeks 1, 2, 3, 4, and 8. RESULTS: Of the total 39 patients enrolled in the study, 26 patients who complied with the protocol criteria completed the minimum four-week study period. During the 12-week evaluation period, seven of the 26 wounds fully healed and an additional eight wounds showed a reduction in size of more than 50 %. Of the remaining 11, five wounds showed moderate healing progression and six wounds did not respond to treatment. Following the 12 week evaluation time point clinicians reported that a further three wounds healed-a 38 % healing rate. CONCLUSION: The results give promise that this advanced gel, containing a macrophage activating substance, can be a tool in re-activating healing in stalled wounds where standard of care is no longer giving the desired healing progression.


Assuntos
Géis/uso terapêutico , Cicatrização , Ferimentos e Lesões/tratamento farmacológico , beta-Glucanas/uso terapêutico , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Estudos Prospectivos
13.
Persoonia ; 38: 240-384, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29151634

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Australia: Banksiophoma australiensis (incl. Banksiophoma gen. nov.) on Banksia coccinea, Davidiellomycesaustraliensis (incl. Davidiellomyces gen. nov.) on Cyperaceae, Didymocyrtis banksiae on Banksia sessilis var. cygnorum, Disculoides calophyllae on Corymbia calophylla, Harknessia banksiae on Banksia sessilis, Harknessia banksiae-repens on Banksia repens, Harknessia banksiigena on Banksia sessilis var. cygnorum, Harknessia communis on Podocarpus sp., Harknessia platyphyllae on Eucalyptus platyphylla, Myrtacremonium eucalypti (incl. Myrtacremonium gen. nov.) on Eucalyptus globulus, Myrtapenidiella balenae on Eucalyptus sp., Myrtapenidiella eucalyptigena on Eucalyptus sp., Myrtapenidiella pleurocarpae on Eucalyptuspleurocarpa, Paraconiothyrium hakeae on Hakea sp., Paraphaeosphaeria xanthorrhoeae on Xanthorrhoea sp., Parateratosphaeria stirlingiae on Stirlingia sp., Perthomyces podocarpi (incl. Perthomyces gen. nov.) on Podocarpus sp., Readeriella ellipsoidea on Eucalyptus sp., Rosellinia australiensis on Banksia grandis, Tiarosporella corymbiae on Corymbia calophylla, Verrucoconiothyriumeucalyptigenum on Eucalyptus sp., Zasmidium commune on Xanthorrhoea sp., and Zasmidium podocarpi on Podocarpus sp. Brazil: Cyathus aurantogriseocarpus on decaying wood, Perenniporia brasiliensis on decayed wood, Perenniporia paraguyanensis on decayed wood, and Pseudocercospora leandrae-fragilis on Leandrafragilis.Chile: Phialocephala cladophialophoroides on human toe nail. Costa Rica: Psathyrella striatoannulata from soil. Czech Republic: Myotisia cremea (incl. Myotisia gen. nov.) on bat droppings. Ecuador: Humidicutis dictiocephala from soil, Hygrocybe macrosiparia from soil, Hygrocybe sangayensis from soil, and Polycephalomyces onorei on stem of Etlingera sp. France: Westerdykella centenaria from soil. Hungary: Tuber magentipunctatum from soil. India: Ganoderma mizoramense on decaying wood, Hodophilus indicus from soil, Keratinophyton turgidum in soil, and Russula arunii on Pterigota alata.Italy: Rhodocybe matesina from soil. Malaysia: Apoharknessia eucalyptorum, Harknessia malayensis, Harknessia pellitae, and Peyronellaea eucalypti on Eucalyptus pellita, Lectera capsici on Capsicum annuum, and Wallrothiella gmelinae on Gmelina arborea.Morocco: Neocordana musigena on Musa sp. New Zealand: Candida rongomai-pounamu on agaric mushroom surface, Candida vespimorsuum on cup fungus surface, Cylindrocladiella vitis on Vitis vinifera, Foliocryphia eucalyptorum on Eucalyptus sp., Ramularia vacciniicola on Vaccinium sp., and Rhodotorula ngohengohe on bird feather surface. Poland: Tolypocladium fumosum on a caterpillar case of unidentified Lepidoptera.Russia: Pholiotina longistipitata among moss. Spain: Coprinopsis pseudomarcescibilis from soil, Eremiomyces innocentii from soil, Gyroporus pseudocyanescens in humus, Inocybe parvicystis in humus, and Penicillium parvofructum from soil. Unknown origin: Paraphoma rhaphiolepidis on Rhaphiolepsis indica.USA: Acidiella americana from wall of a cooling tower, Neodactylaria obpyriformis (incl. Neodactylaria gen. nov.) from human bronchoalveolar lavage, and Saksenaea loutrophoriformis from human eye. Vietnam: Phytophthora mekongensis from Citrus grandis, and Phytophthora prodigiosa from Citrus grandis. Morphological and culture characteristics along with DNA barcodes are provided.

14.
J Evol Biol ; 29(8): 1631-42, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27206242

RESUMO

Mating patterns and natural selection play important roles in determining whether genetic polymorphisms are maintained or lost. Here, we document an atypical population of Lapeirousia anceps (Iridaceae) with a bimodal distribution of floral-tube length and investigate the reproductive mechanisms associated with this pattern of variation. Flowers were visited exclusively by the long-proboscid fly Moegistorhynchus longirostris (Nemestrinidae), which exhibited a unimodal distribution of proboscis length and displayed a preference for long-tubed phenotypes. Despite being visited by a single pollinator species, allozyme markers revealed significant genetic differentiation between open-pollinated progeny of long- and short-tubed phenotypes suggesting mating barriers between them. We obtained direct evidence for mating barriers between the floral-tube phenotypes through observations of pollinator foraging, controlled hand pollinations and measurements of pollen competition and seed set. Intermediate tube-length phenotypes produced fewer seeds in the field than either long- or short-tubed phenotypes. Although floral-tube length bimodality may not be a stable state over long timescales, reproductive barriers to mating and low 'hybrid' fitness have the potential to contribute to the maintenance of this state in the short term.


Assuntos
Aptidão Genética , Iridaceae/fisiologia , Polinização , Animais , Flores , Iridaceae/crescimento & desenvolvimento , Reprodução , Seleção Genética
15.
Phys Chem Chem Phys ; 18(35): 24396-400, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27535898

RESUMO

A characteristic reflection anisotropy spectrum (RAS) is observed from a Au(110) surface in a wide range of electrolytes and combinations of pH and applied potentials. It is suggested that this common RAS profile arises from an interaction between the potential applied to the Au(110) electrode and the dipole moments of oxidized species that locates the Fermi level at a common position with respect to the electronic band structure of Au. Rapid changes in this RAS profile are observed for Au(110)/H2SO4 as the potential is switched between 0.3 V and 0.6 V, a potential range in which the surface is not reconstructed and below the potential range of surface oxidation. The spectral changes are completed in less than 10 ms, are reversible and are attributed to the replacement of adsorbed anions by an oxygenated species.

16.
Persoonia ; 37: 218-403, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28232766

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Australia: Apiognomonia lasiopetali on Lasiopetalum sp., Blastacervulus eucalyptorum on Eucalyptus adesmophloia, Bullanockia australis (incl. Bullanockia gen. nov.) on Kingia australis, Caliciopsis eucalypti on Eucalyptus marginata, Celerioriella petrophiles on Petrophile teretifolia, Coleophoma xanthosiae on Xanthosia rotundifolia, Coniothyrium hakeae on Hakea sp., Diatrypella banksiae on Banksia formosa, Disculoides corymbiae on Corymbia calophylla, Elsinoë eelemani on Melaleuca alternifolia, Elsinoë eucalyptigena on Eucalyptus kingsmillii, Elsinoë preissianae on Eucalyptus preissiana, Eucasphaeria rustici on Eucalyptus creta, Hyweljonesia queenslandica (incl. Hyweljonesia gen. nov.) on the cocoon of an unidentified microlepidoptera, Mycodiella eucalypti (incl. Mycodiella gen. nov.) on Eucalyptus diversicolor, Myrtapenidiella sporadicae on Eucalyptus sporadica, Neocrinula xanthorrhoeae (incl. Neocrinula gen. nov.) on Xanthorrhoea sp., Ophiocordyceps nooreniae on dead ant, Phaeosphaeriopsis agavacearum on Agave sp., Phlogicylindrium mokarei on Eucalyptus sp., Phyllosticta acaciigena on Acacia suaveolens, Pleurophoma acaciae on Acacia glaucoptera, Pyrenochaeta hakeae on Hakea sp., Readeriella lehmannii on Eucalyptus lehmannii, Saccharata banksiae on Banksia grandis, Saccharata daviesiae on Daviesia pachyphylla, Saccharata eucalyptorum on Eucalyptus bigalerita, Saccharata hakeae on Hakea baxteri, Saccharata hakeicola on Hakea victoria, Saccharata lambertiae on Lambertia ericifolia, Saccharata petrophiles on Petrophile sp., Saccharata petrophilicola on Petrophile fastigiata, Sphaerellopsis hakeae on Hakea sp., and Teichospora kingiae on Kingia australis.Brazil: Adautomilanezia caesalpiniae (incl. Adautomilanezia gen. nov.) on Caesalpina echinata, Arthrophiala arthrospora (incl. Arthrophiala gen. nov.) on Sagittaria montevidensis, Diaporthe caatingaensis (endophyte from Tacinga inamoena), Geastrum ishikawae on sandy soil, Geastrum pusillipilosum on soil, Gymnopus pygmaeus on dead leaves and sticks, Inonotus hymenonitens on decayed angiosperm trunk, Pyricularia urashimae on Urochloa brizantha, and Synnemellisia aurantia on Passiflora edulis. Chile: Tubulicrinis australis on Lophosoria quadripinnata.France: Cercophora squamulosa from submerged wood, and Scedosporium cereisporum from fluids of a wastewater treatment plant. Hawaii: Beltraniella acaciae, Dactylaria acaciae, Rhexodenticula acaciae, Rubikia evansii and Torula acaciae (all on Acacia koa).India: Lepidoderma echinosporum on dead semi-woody stems, and Rhodocybe rubrobrunnea from soil. Iran: Talaromyces kabodanensis from hypersaline soil. La Réunion: Neocordana musarum from leaves of Musa sp. Malaysia: Anungitea eucalyptigena on Eucalyptus grandis × pellita, Camptomeriphila leucaenae (incl. Camptomeriphila gen. nov.) on Leucaena leucocephala, Castanediella communis on Eucalyptus pellita, Eucalyptostroma eucalypti (incl. Eucalyptostroma gen. nov.) on Eucalyptus pellita, Melanconiella syzygii on Syzygium sp., Mycophilomyces periconiae (incl. Mycophilomyces gen. nov.) as hyperparasite on Periconia on leaves of Albizia falcataria, Synnemadiella eucalypti (incl. Synnemadiella gen. nov.) on Eucalyptus pellita, and Teichospora nephelii on Nephelium lappaceum.Mexico: Aspergillus bicephalus from soil. New Zealand: Aplosporella sophorae on Sophora microphylla, Libertasomyces platani on Platanus sp., Neothyronectria sophorae (incl. Neothyronectria gen. nov.) on Sophora microphylla, Parastagonospora phoenicicola on Phoenix canariensis, Phaeoacremonium pseudopanacis on Pseudopanax crassifolius, Phlyctema phoenicis on Phoenix canariensis, and Pseudoascochyta novae-zelandiae on Cordyline australis.Panama: Chalara panamensis from needle litter of Pinus cf. caribaea. South Africa: Exophiala eucalypti on leaves of Eucalyptus sp., Fantasmomyces hyalinus (incl. Fantasmomyces gen. nov.) on Acacia exuvialis, Paracladophialophora carceris (incl. Paracladophialophora gen. nov.) on Aloe sp., and Umthunziomyces hagahagensis (incl. Umthunziomyces gen. nov.) on Mimusops caffra.Spain: Clavaria griseobrunnea on bare ground in Pteridium aquilinum field, Cyathus ibericus on small fallen branches of Pinus halepensis, Gyroporus pseudolacteus in humus of Pinus pinaster, and Pseudoascochyta pratensis (incl. Pseudoascochyta gen. nov.) from soil. Thailand: Neoascochyta adenii on Adenium obesum, and Ochroconis capsici on Capsicum annuum. UK: Fusicolla melogrammae from dead stromata of Melogramma campylosporum on bark of Carpinus betulus. Uruguay: Myrmecridium pulvericola from house dust. USA: Neoscolecobasidium agapanthi (incl. Neoscolecobasidium gen. nov.) on Agapanthus sp., Polyscytalum purgamentum on leaf litter, Pseudopithomyces diversisporus from human toenail, Saksenaea trapezispora from knee wound of a soldier, and Sirococcus quercus from Quercus sp. Morphological and culture characteristics along with DNA barcodes are provided.

17.
Int J Sports Med ; 36(1): 41-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25259591

RESUMO

This study compared the intensity distribution of time-motion analysis data, when speed zones were categorized by different methods. 12 U18 players undertook a routine battery of laboratory- and field-based assessments to determine their running speed corresponding to the respiratory compensation threshold (RCT), maximal aerobic speed (MAS), maximal oxygen consumption (vV˙O2max) and maximal sprint speed (MSS). Players match-demands were tracked using 5 Hz GPS units in 22 fixtures (50 eligible match observations). The percentage of total distance covered running at high-speed (%HSR), very-high speed (%VHSR) and sprinting were determined using the following speed thresholds: (1) arbitrary; (2) individualised (IND) using RCT, vV˙O2max and MSS; (3) individualised via MAS per se; (4) individualised via MSS per se; and (5) individualised using MAS and MSS as measures of locomotor capacities (LOCO). Using MSS in isolation resulted in 61% and 39% of player's % HSR and % VHSR, respectively, being incorrectly interpreted, when compared to the IND technique. Estimating the RCT from fractional values of MAS resulted in erroneous interpretations of % HSR in 50% of cases. The present results suggest that practitioners and researchers should avoid using singular fitness characteristics to individualise the intensity distribution of time-motion analysis data. A combination of players' anaerobic threshold, MAS, and MSS characteristics are recommended to individualise player-tracking data.


Assuntos
Aptidão Física/fisiologia , Corrida/fisiologia , Estudos de Tempo e Movimento , Adolescente , Limiar Anaeróbio , Sistemas de Informação Geográfica , Humanos , Consumo de Oxigênio , Futebol/fisiologia
18.
J Spinal Disord Tech ; 28(10): 352-62, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26566255

RESUMO

Surgical site infections (SSIs) are a potentially devastating complication of spine surgery. SSIs are defined by the Centers for Disease Control and Prevention as occurring within 30 days of surgery or within 12 months of placement of foreign bodies, such as spinal instrumentation. SSIs are commonly categorized by the depth of surgical tissue involvement (ie, superficial, deep incisional, or organ and surrounding space). Postoperative infections result in increased costs and postoperative morbidity. Because continued research has improved the evaluation and management of spinal infections, spine surgeons must be aware of these modalities. The controversies in evaluation and management of SSIs in spine surgery will be reviewed.


Assuntos
Procedimentos Ortopédicos/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Diagnóstico por Imagem , Humanos , Fatores de Risco , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/terapia
19.
J Spinal Disord Tech ; 28(6): E316-27, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26079841

RESUMO

Spinal infections have historically been associated with significant morbidity and mortality. Current treatment protocols have improved patient outcomes through prompt and accurate infection identification, medical treatment, and surgical interventions. Medical and surgical management, however, remains controversial because of a paucity of high-level evidence to guide decision making. Despite this, an awareness of presenting symptoms, pertinent risk factors, and common imaging findings are critical for treating spine infections. The purpose of this article is to review the recent literature and present the latest evidence-based recommendations for the most commonly encountered primary spinal infections: vertebral osteomyelitis and epidural abscess.


Assuntos
Abscesso Epidural/terapia , Osteomielite/terapia , Doenças da Coluna Vertebral/terapia , Abscesso Epidural/complicações , Abscesso Epidural/diagnóstico , Abscesso Epidural/microbiologia , Granuloma/patologia , Humanos , Imageamento por Ressonância Magnética , Osteomielite/diagnóstico , Osteomielite/etiologia , Osteomielite/microbiologia , Doenças da Coluna Vertebral/diagnóstico , Doenças da Coluna Vertebral/etiologia , Doenças da Coluna Vertebral/microbiologia
20.
Mol Microbiol ; 87(6): 1277-89, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23368090

RESUMO

Cell cycle transitions are often triggered by the proteolysis of key regulatory proteins. In Caulobacter crescentus, the G1-S transition involves the degradation of an essential DNA-binding response regulator, CtrA, by the ClpXP protease. Here, we show that another critical cell cycle regulator, SciP, is also degraded during the G1-S transition, but by the Lon protease. SciP is a small protein that binds directly to CtrA and prevents it from activating target genes during G1. We demonstrate that SciP must be degraded during the G1-S transition so that cells can properly activate CtrA-dependent genes following DNA replication initiation and the reaccumulation of CtrA. These results indicate that like CtrA, SciP levels are tightly regulated during the Caulobacter cell cycle. In addition, we show that formation of a complex between CtrA and SciP at target promoters protects both proteins from their respective proteases. Degradation of either protein thus helps trigger the destruction of the other, facilitating a cooperative disassembly of the complex. Collectively, our results indicate that ClpXP and Lon each degrade an important cell cycle regulator, helping to trigger the onset of S phase and prepare cells for the subsequent programmes of gene expression critical to polar morphogenesis and cell division.


Assuntos
Caulobacter crescentus/fisiologia , Ciclo Celular , Regulação Bacteriana da Expressão Gênica , Fator 6 de Transcrição de Octâmero/metabolismo , Protease La/metabolismo , Caulobacter crescentus/citologia , Caulobacter crescentus/genética , Caulobacter crescentus/crescimento & desenvolvimento , Proteólise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA