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1.
Plant Cell ; 35(5): 1360-1385, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36808541

RESUMO

The rice blast fungus Magnaporthe oryzae causes a devastating disease that threatens global rice (Oryza sativa) production. Despite intense study, the biology of plant tissue invasion during blast disease remains poorly understood. Here we report a high-resolution transcriptional profiling study of the entire plant-associated development of the blast fungus. Our analysis revealed major temporal changes in fungal gene expression during plant infection. Pathogen gene expression could be classified into 10 modules of temporally co-expressed genes, providing evidence for the induction of pronounced shifts in primary and secondary metabolism, cell signaling, and transcriptional regulation. A set of 863 genes encoding secreted proteins are differentially expressed at specific stages of infection, and 546 genes named MEP (Magnaportheeffector protein) genes were predicted to encode effectors. Computational prediction of structurally related MEPs, including the MAX effector family, revealed their temporal co-regulation in the same co-expression modules. We characterized 32 MEP genes and demonstrate that Mep effectors are predominantly targeted to the cytoplasm of rice cells via the biotrophic interfacial complex and use a common unconventional secretory pathway. Taken together, our study reveals major changes in gene expression associated with blast disease and identifies a diverse repertoire of effectors critical for successful infection.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Magnaporthe/fisiologia , Ascomicetos/metabolismo , Transdução de Sinais , Citoplasma/metabolismo , Oryza/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
2.
PLoS Biol ; 21(4): e3002052, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37040332

RESUMO

Wheat, one of the most important food crops, is threatened by a blast disease pandemic. Here, we show that a clonal lineage of the wheat blast fungus recently spread to Asia and Africa following two independent introductions from South America. Through a combination of genome analyses and laboratory experiments, we show that the decade-old blast pandemic lineage can be controlled by the Rmg8 disease resistance gene and is sensitive to strobilurin fungicides. However, we also highlight the potential of the pandemic clone to evolve fungicide-insensitive variants and sexually recombine with African lineages. This underscores the urgent need for genomic surveillance to track and mitigate the spread of wheat blast outside of South America and to guide preemptive wheat breeding for blast resistance.


Assuntos
Pandemias , Triticum , Triticum/genética , Melhoramento Vegetal , Doenças das Plantas/microbiologia , Genômica , Fungos
3.
Proc Natl Acad Sci U S A ; 120(12): e2301358120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36913579

RESUMO

To cause rice blast disease, the filamentous fungus Magnaporthe oryzae secretes a battery of effector proteins into host plant tissue to facilitate infection. Effector-encoding genes are expressed only during plant infection and show very low expression during other developmental stages. How effector gene expression is regulated in such a precise manner during invasive growth by M. oryzae is not known. Here, we report a forward-genetic screen to identify regulators of effector gene expression, based on the selection of mutants that show constitutive effector gene expression. Using this simple screen, we identify Rgs1, a regulator of G-protein signaling (RGS) protein that is necessary for appressorium development, as a novel transcriptional regulator of effector gene expression, which acts prior to plant infection. We show that an N-terminal domain of Rgs1, possessing transactivation activity, is required for effector gene regulation and acts in an RGS-independent manner. Rgs1 controls the expression of at least 60 temporally coregulated effector genes, preventing their transcription during the prepenetration stage of development prior to plant infection. A regulator of appressorium morphogenesis is therefore also required for the orchestration of pathogen gene expression required for invasive growth by M. oryzae during plant infection.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Magnaporthe/genética , Ascomicetos/genética , Transdução de Sinais , Expressão Gênica , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Oryza/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
4.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260397

RESUMO

Family planning programs are believed to have substantial long-term benefits for women's health and well-being, yet few studies have established either extent or direction of long-term effects. The Matlab, Bangladesh, maternal and child health/family planning (MCH/FP) program afforded a 12-y period of well-documented differential access to services. We evaluate its impacts on women's lifetime fertility, adult health, and economic outcomes 35 y after program initiation. We followed 1,820 women who were of reproductive age during the differential access period (born 1938-1973) from 1978 to 2012 using prospectively collected data from the Matlab Health and Demographic Surveillance System and the 1996 and 2012 Matlab Health and Socioeconomic Surveys. We estimated intent-to-treat single-difference models comparing treatment and comparison area women. MCH/FP significantly increased contraceptive use, reduced completed fertility, lengthened birth intervals, and reduced age at last birth, but had no significant positive impacts on health or economic outcomes. Treatment area women had modestly poorer overall health (+0.07 SD) and respiratory health (+0.12 SD), and those born 1950-1961 had significantly higher body mass index (BMI) in 1996 (0.76 kg/m2) and 2012 (0.57 kg/m2); fewer were underweight in 1996, but more were overweight or obese in 2012. Overall, there was a +2.5 kg/m2 secular increase in BMI. We found substantial changes in lifetime contraceptive and fertility behavior but no long-term health or economic benefits of the program. We observed modest negative health impacts that likely result from an accelerated nutritional transition among treated women, a transition that would, in an earlier context, have been beneficial.


Assuntos
Saúde da Criança , Serviços de Planejamento Familiar , Saúde Materna , Idoso , Bangladesh , Índice de Massa Corporal , Estudos de Coortes , Comportamento Contraceptivo , Feminino , Humanos , Fatores de Tempo
5.
Angew Chem Int Ed Engl ; 63(1): e202316356, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37983661

RESUMO

Superglassy membranes synthesised by polymers of intrinsic microporosity (PIMs) suffer from physical aging and show poor gas permeance over time, especially thin membranes, due to the fast rearrangement of nonequilibrium polymer chains. Herein, we constructed a novel PIM-1 thin film nanocomposite membrane (TFN) using nanosized UiO-66-NH2 (≈10 nm)/carboxylated PIM-1 (cPIM-1) as the composite filler. Unlike conventional fillers, which interact with the polymer only via the surface, the UiO-66-NH2 /cPIM-1 forms a stable three-dimensional (3D) network intertwining with the polymer chains, being very effective to impede chain relaxation, and thus physical aging. Nanosizing of UiO-66-NH2 was achieved by regulating the nucleation kinetics using carbon quantum dots (CQD) during the synthesis. This led to increased surface area, and hence more functional groups to bond with cPIM-1 (via hydrogen bonding between -NH2 and -COOH groups), which also improved interfacial compatibility between the 3D network and polymer chains avoiding defect formation. As a result, the novel TFN showed significantly improved performance in gas separation along with reduced aging (i.e. ≈6 % loss in CO2 permeability over 63 days); the aged membranes had a CO2 permeance of 2504 GPU and ideal selectivity values of 37.2 and 23.8 for CO2 /N2 and CO2 /CH4 , respectively.

6.
Aust N Z J Psychiatry ; 57(1): 17-20, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35341348

RESUMO

Recovery Colleges are an innovative education-based approach to support mental health recovery that, following the recent Royal Commission, will have to be established in every area mental health service within the state of Victoria. This paper describes the rationale, benefits and some of the key considerations to successfully establish Recovery Colleges. The establishment of Recovery Colleges has the potential to drive culture change within mental health services and embed recovery orientation within service provision as well as engaging service users in their own recovery journey. There are significant challenges, however, in implementing the collaborative, co-produced model within the constraints of a publicly funded mental health clinical service. This paper considers some of the practice implications for public mental health services in developing and integrating Recovery Colleges. The paper, like everything we do at the Recovery College, is co-produced and co-authored - in this case, by a lived experience expert, a medically trained expert and a research/writing expert.


Assuntos
Transtornos Mentais , Serviços de Saúde Mental , Humanos , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Escolaridade
7.
Artigo em Inglês | MEDLINE | ID: mdl-33526492

RESUMO

Implantable orthopedic devices have had an enormously positive impact on human health; however, despite best practice, patients are prone to developing orthopedic device-related infections (ODRI) that have high treatment failure rates. One barrier to the development of improved treatment options is the lack of an animal model that may serve as a robust preclinical assessment of efficacy. We present a clinically relevant large animal model of chronic methicillin-resistant Staphylococcus aureus (MRSA) ODRI that persists despite current clinical practice in medical and surgical treatment at rates equivalent to clinical observations. Furthermore, we showed that an injectable, thermoresponsive, hyaluronic acid-based hydrogel loaded with gentamicin and vancomycin outperforms current clinical practice treatment in this model, eliminating bacteria from all animals. These results confirm that local antibiotic delivery with an injectable hydrogel can dramatically increase treatment success rates beyond current clinical practice, with efficacy proven in a robust animal model.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/uso terapêutico , Gentamicinas , Humanos , Ácido Hialurônico , Hidrogéis , Ovinos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina
8.
Nat Chem Biol ; 15(3): 241-249, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30692683

RESUMO

There is a challenge for metalloenzymes to acquire their correct metals because some inorganic elements form more stable complexes with proteins than do others. These preferences can be overcome provided some metals are more available than others. However, while the total amount of cellular metal can be readily measured, the available levels of each metal have been more difficult to define. Metal-sensing transcriptional regulators are tuned to the intracellular availabilities of their cognate ions. Here we have determined the standard free energy for metal complex formation to which each sensor, in a set of bacterial metal sensors, is attuned: the less competitive the metal, the less favorable the free energy and hence the greater availability to which the cognate allosteric mechanism is tuned. Comparing these free energies with values derived from the metal affinities of a metalloprotein reveals the mechanism of correct metalation exemplified here by a cobalt chelatase for vitamin B12.


Assuntos
Transferência de Energia/fisiologia , Metaloproteínas/metabolismo , Metais/metabolismo , Marcadores de Afinidade/metabolismo , Bactérias/enzimologia , Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/fisiologia , Metaloproteínas/fisiologia , Salmonella/metabolismo
9.
Indoor Air ; 31(3): 628-638, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33016379

RESUMO

Indoor air pollution (IAP) is a recognized risk factor for various diseases. This paper examines the role of indoor solid fuel exposure in the risk of mycobacterium tuberculosis (TB) in Delhi Metropolitan, India. Using a cross-sectional design, subjects were screened for a history of active TB and lifelong exposure to IAP sources, such as solid fuel burning and kerosene. The TB prevalence rate in the study area was 1117 per 100 000 population. Every year, increase in solid fuel exposure was associated with a three percent higher likelihood of a history of active TB. Subjects exposed to solid fuel and kerosene use for both heating home and cooking showed significant associations with TB. Age, household expenditure (a proxy of income), lung function, and smoking also showed significant associations with TB. Smokers and solid fuel-exposed subjects were four times more likely to have a history of active TB than non-smoker and unexposed subjects. These finding calls strategies to mitigate solid fuel exposure, such as use of clean cookstove and ventilation, to mitigate the risk of TB which aligns with the United Nations' goal of "End TB by 2030."


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Exposição por Inalação/estatística & dados numéricos , Tuberculose/epidemiologia , Estudos de Casos e Controles , Culinária , Estudos Transversais , Calefação , Humanos , Índia/epidemiologia , Querosene , Fatores de Risco , Ventilação
10.
J Shoulder Elbow Surg ; 30(6): 1410-1422, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33373684

RESUMO

BACKGROUND: Cutibacterium acnes is a commensal, gram-positive, facultatively anaerobic bacillus that resides in the dermis. Historically thought to be a contaminant when identified on cultured specimens, recent advances in diagnostic technology have now implicated it as the most common organism responsible for postoperative shoulder infections. Despite a recognition of the role of this organism and a significant research interest in recent years, there is clear lack of consensus guideline on strategies to prevent, diagnose, and treat postoperative shoulder infection. METHOD: The electronic databases PubMed, MEDLINE, CINAHL, Scopus, and Web of Science were searched in March 2020. All experimental and nonexperimental studies that investigate C acnes in shoulder surgery were included. Inclusion was limited to articles published after 2000 and written in English; reviews, gray literature, or abstracts were excluded. A total of 70 studies were included in this review. This scoping review was performed in accordance with the Extended Preferred Reporting Items of Systematic Reviews and Meta-Analyses Statement for Scoping Reviews (PRISMA-ScR). RESULTS: Standard surgical prophylactic regimens such as intravenous antibiotics and topical chlorhexidine are ineffective at removing C acnes from the deep layer of the dermis, and there is a shift toward using topical benzoyl peroxide with significantly improved efficacy. An improved understanding of the bacteria has demonstrated that a prolonged culture time of up to 14 days is needed, especially in cases of established infection. Advances in diagnostics such as sonication and molecular-based testing are promising. Although usually thought to be susceptible to a broad range of antibiotics, resistance is emerging to clindamycin. An improved understanding of its ability to form a biofilm highlights the difficulty in treating an established infection. CONCLUSION: The role of C acnes causing postoperative infection following shoulder surgery is being increasingly recognized. Strategies for prevention, diagnosis, and treatment have been outlined from both an antimicrobial and surgical perspective. A number of these strategies are emerging and require further research to demonstrate efficacy before implementation into clinical guidelines.


Assuntos
Infecções por Bactérias Gram-Positivas , Articulação do Ombro , Peróxido de Benzoíla , Clindamicina , Humanos , Propionibacterium acnes , Ombro , Articulação do Ombro/cirurgia
11.
Int J Mol Sci ; 23(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35008825

RESUMO

Diseases caused by dimorphic phytopathogenic and systemic dimorphic fungi have markedly increased in prevalence in the last decades, and understanding the morphogenic transition to the virulent state might yield novel means of controlling dimorphic fungi. The dimorphic fungus Z. tritici causes significant economic impact on wheat production, and yet the regulation of the dimorphic switch, a key first step in successful plant colonization, is still largely unexplored in this fungus. The fungus is amenable to suppression by fungicides at this switch point, and the identification of the factors controlling the dimorphic switch provides a potential source of novel targets to control Septoria tritici blotch (STB). Inhibition of the dimorphic switch can potentially prevent penetration and avoid any damage to the host plant. The aim of the current work was to unveil genetic determinants of the dimorphic transition in Z. tritici by using a forward genetics strategy. Using this approach, we unveiled two novel factors involved in the switch to the pathogenic state and used reverse genetics and complementation to confirm the role of the novel virulence factors and further gained insight into the role of these genes, using transcriptome analysis via RNA-Seq. The transcriptomes generated potentially contain key determinants of the dimorphic transition.


Assuntos
Agrobacterium/metabolismo , Ascomicetos/genética , Ascomicetos/patogenicidade , Proteínas Fúngicas/metabolismo , Mutagênese Insercional/genética , Fatores de Virulência/metabolismo , Ascomicetos/crescimento & desenvolvimento , Sequência de Bases , Parede Celular/metabolismo , DNA Bacteriano/genética , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Ontologia Genética , Genes Fúngicos , Inativação Metabólica , Metabolismo dos Lipídeos , Metais/metabolismo , Mutação/genética , Estresse Oxidativo/genética , Pigmentação/genética , Proteólise , Temperatura , Transcrição Gênica , Virulência/genética
12.
Vet Anaesth Analg ; 48(2): 272-276, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341361

RESUMO

OBJECTIVE: To describe a novel in-plane ultrasound (U/S)-guided temporal approach to peribulbar block in dogs. STUDY DESIGN: Prospective experimental cadaver study. ANIMALS: A group of 10 Beagle cadavers. METHODS: After describing the U/S anatomy, peribulbar injection was performed bilaterally in 10 thawed Beagle cadavers by two randomly assigned operators. A 5-8 MHz microconvex U/S probe was positioned caudal to the orbital ligament in the longitudinal plane. Using an in-plane technique, methylene blue dye was injected in five dogs (10 eyes total), while methylene blue dye and iohexol contrast mixture (50:50) were injected in the remaining five dogs. Injection volume was 0.2 mL cm-1 of cranial length. A computed tomography (CT) scan was performed on dogs injected with dye and contrast to identify spread of contrast. Dissection to visualize dye spread in the orbit was performed in all dogs. Injection success was defined as spread of contrast into the peribulbar space. The pattern of distribution of contrast-dye was also assessed. Comparisons between operator and bilateral injections were assessed using a Student t test (p < 0.05). All other data are reported as number (n/N) and percentage (%). RESULTS: Peribulbar spread was noted in 19/20 injections (95%) on dissection. CT imaging (five dogs) illustrated peribulbar contrast spread in 9/10 injections (90%), with mixed peribulbar/retrobulbar spread for the remaining injection. Contrast was present at the rostral alar foramen in 4/10 (40%) injections, orbital fissure in 5/10 (50%), oval foramen in 1/10 (10%), maxillary nerve in 3/10 (30%) and intracranial in 5/10 (50%). Coverage of the maxillary nerve was noted on 3/20 (15%) injections on dissection. No further dye spread was noted. CONCLUSIONS AND CLINICAL RELEVANCE: This technique demonstrated peribulbar spread of injectate in 100% of injections for the 10 canine cadavers studied. Further studies are required to evaluate this technique clinically.


Assuntos
Doenças do Cão , Bloqueio Nervoso , Animais , Cadáver , Cães , Bloqueio Nervoso/veterinária , Estudos Prospectivos , Ultrassonografia , Ultrassonografia de Intervenção/veterinária
13.
Vet Anaesth Analg ; 48(1): 125-133, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33334690

RESUMO

OBJECTIVE: To examine the anatomy of the lumbar epaxial region and to describe two different ultrasound-guided approaches for the lumbar erector spinae plane (ESP) block in dogs. STUDY DESIGN: An anatomical and experimental cadaver study. ANIMALS: A group of 19 canine cadavers. METHODS: The anatomy was described following dissection of two cadavers. Bilateral ultrasound-guided ESP injections with 0.4 mL kg-1 of contrast dye were performed in 17 adult Beagle cadavers using either transversal (TVS) or parasagittal (PST) approaches. Computed tomography was performed to measure the total length of the contrast dye column and the epidural, intravascular, hypaxial and intra-abdominal migration. Dissections were performed to assess the spread of the contrast dye and to determine the degree of staining of the dorsal branches of the spinal nerves (DBSN). Mann-Whitney U and chi-square tests were used to compare data between groups. RESULTS: Using both techniques, the contrast dye was observed within the ESP compartment. There was no difference in the total length of the contrast dye column between TVS and PST approaches (p = 0.056). Using the TVS approach, multisegmental staining of the DBSN was visible with 100% (17/17) of injections, while complete staining of the DBSN was achieved at 94% of the injection sites. Using the PST approach, these values were 29% (5/17) and 23% (4/17), respectively. The TVS approach stained more DBSN than the PST approach (p = 0.001), with a median (range) of 2 (2-3) versus 0 (0-3) DBSN, respectively. Using the TVS approach, epidural and intravascular migration were present in 2/17 (p = 0.485) and 3/17 (p = 0.227) injections, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Both ultrasound-guided approaches resulted in a spread of the contrast dye within the ESP compartment. Although there were no differences in the total length of the contrast dye column, the TVS approach was superior to the PST approach in staining DBSN.


Assuntos
Doenças do Cão , Bloqueio Nervoso , Animais , Cadáver , Cães , Bloqueio Nervoso/veterinária , Músculos Paraespinais/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Ultrassonografia de Intervenção/veterinária
14.
Macromol Rapid Commun ; 41(2): e1900572, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31846137

RESUMO

Microporous polymer nanosheets with thicknesses in the range 3-5 nm and with high apparent surface area (Brunauer-Emmett-Teller surface area 940 m2 g-1 ) are formed when the effectively bifunctional (tetrafluoro) monomer used in the preparation of the prototypical polymer of intrinsic microporosity PIM-1 is replaced with an effectively tetrafunctional (octafluoro) monomer to give a tightly crosslinked network structure. When employed as a filler in mixed-matrix membranes based on PIM-1, a low loading of 0.5 wt% network-PIM-1 nanosheets gives rise to enhanced CO2 permeability and CO2 /CH4 selectivity, compared to pure PIM-1.


Assuntos
Membranas Artificiais , Nanoestruturas/química , Polímeros/química , Dióxido de Carbono/química , Gases/química , Metano/química , Nanoestruturas/ultraestrutura , Permeabilidade , Porosidade
15.
Demography ; 57(5): 1951-1974, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32935300

RESUMO

Reports of rising income segregation in the United States have been brought into question by the observation that post-2000 estimates are upwardly biased because of a reduction in the sample sizes on which they are based. Recent studies have offered estimates of this sample-count bias using public data. We show here that there are two substantial sources of systematic bias in estimating segregation levels: bias associated with sample size and bias associated with using weighted sample data. We rely on new correction methods using the original census sample data for individual households to provide more accurate estimates. Family income segregation rose markedly in the 1980s but only selectively after 1990. For some categories of families, segregation declined after 1990. There has been an upward trend for families with children but not specifically for families with children in the upper or lower 10% of the income distribution. Separate analyses by race/ethnicity show that income segregation was not generally higher among Blacks and Hispanics than among White families, and evidence of income segregation trends for these separate groups is mixed. Income segregation increased for all three racial groups for families with children, particularly for Hispanics (but not Whites or Blacks) in the upper 10% of the income distribution. Trends vary for specific combinations of race/ethnicity, presence of children, and location in the income distribution, offering new challenges for understanding the underlying processes of change.


Assuntos
Características da Família , Renda/estatística & dados numéricos , Grupos Raciais/estatística & dados numéricos , Segregação Social/tendências , Viés , Humanos , Projetos de Pesquisa , Estados Unidos
16.
J Synchrotron Radiat ; 26(Pt 1): 45-51, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30655467

RESUMO

The tangential curvature of actively bent X-ray mirrors at synchrotron radiation and X-ray free-electron laser (XFEL) facilities is typically only changed every few hours or even days. This operation can take tens of minutes for active optics with multiple bending actuators and often requires expert guidance using in situ monitoring devices. Hence, the dynamic performance of active X-ray optics for synchrotron beamlines has historically not been exploited. This is in stark contrast to many other scientific fields. However, many areas of synchrotron radiation and XFEL science, including macromolecular crystallography, could greatly benefit from the ability to change the size and shape of the X-ray beam rapidly and continuously. The advantages of this innovative approach are twofold: a large reduction in the dead time required to change the size of the X-ray beam for different-sized samples and the possibility of making multiple changes to the beam during the measurement of a single sample. In the preceding paper [Part I; Alcock, Nistea, Signorato & Sawhney (2019), J. Synchrotron Rad. 26, 36-44], which accompanies this article, high-speed visible-light Fizeau interferometry was used to identify the factors which influence the dynamic bending behaviour of piezoelectric bimorph deformable X-ray mirrors. Building upon this ex situ metrology study, provided here is the first synchrotron radiation beamline implementation of high-speed adaptive X-ray optics using two bimorphs operating as a Kirkpatrick-Baez pair. With optimized substrates, novel opto-mechanical holders and a next-generation high-voltage power supply, the size of an X-ray beam was rapidly and repeatedly switched in <10 s. Of equal importance, it is also shown that compensation of piezoelectric creep ensures that the X-ray beam size remains stable for more than 1 h after making a major change. The era of high-speed adaptive X-ray optics for synchrotron radiation and XFEL beamlines has begun.

17.
Nat Chem Biol ; 13(4): 409-414, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28166209

RESUMO

The metal affinities of metal-sensing transcriptional regulators co-vary with cellular metal concentrations over more than 12 orders of magnitude. To understand the cause of this relationship, we determined the structure of the Ni(II) sensor InrS and then created cyanobacteria (Synechocystis PCC 6803) in which transcription of genes encoding a Ni(II) exporter and a Ni(II) importer were controlled by InrS variants with weaker Ni(II) affinities. Variant strains were sensitive to elevated nickel and contained more nickel, but the increase was small compared with the change in Ni(II) affinity. All of the variant sensors retained the allosteric mechanism that inhibits DNA binding following metal binding, but a response to nickel in vivo was observed only when the sensitivity was set to respond in a relatively narrow (less than two orders of magnitude) range of nickel concentrations. Thus, the Ni(II) affinity of InrS is attuned to cellular metal concentrations rather than the converse.


Assuntos
Níquel/análise , Níquel/química , Proteínas Repressoras/química , Soluções Tampão , Modelos Moleculares , Níquel/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Synechocystis/metabolismo
18.
BMC Health Serv Res ; 18(1): 210, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29580254

RESUMO

BACKGROUND: The role of the "debrief" to address issues related to patient safety and systematic flaws in care is frequently overlooked. In our study, we interview surgical leaders who have developed successful strategies of debriefing within a comprehensive program of quality improvement. METHODS: Semi-structured interviews of four implementation leaders were performed. The observations, beliefs and strategies of surgical leaders are compared and contrasted. Common themes are identified related to program success and failure. Quality and safety researchers performed, coded and categorized the interviews and coordinated the analysis and interpretation of the results. The authors from the four institutions aided in interpretation and framing of the results. RESULTS: The debriefing programs evaluated were part of comprehensive quality improvement projects. Seven high-level themes and 24 subthemes were identified from the interviews. Themes related to leadership included early engagement, visible ongoing commitment and enforcement. Success appeared to depend upon meaningful and early debriefing feedback. The culture of safety that promoted success included a commitment to open and fair communication and continuous improvement. There were many challenges to the success of debriefing programs. The loss of institutional commitment of resources and personnel was the instigating factor behind the collapse of the program at Michigan. Other areas of potential failure included communication issues and loss of early and meaningful feedback. CONCLUSIONS: Leaders of four surgical systems with strong debriefing programs report success using debriefing to improve system performance. These findings are consistent with previously published studies. Success requires commitment of resources, and leadership engagement. The greatest gains may be best achieved by programs that provide meaningful debriefing feedback in an atmosphere dedicated to open communication.


Assuntos
Feedback Formativo , Equipe de Assistência ao Paciente/organização & administração , Segurança do Paciente , Melhoria de Qualidade/organização & administração , Procedimentos Cirúrgicos Operatórios , Comunicação , Atenção à Saúde , Pesquisa sobre Serviços de Saúde , Humanos , Relações Interprofissionais , Liderança , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa , Gestão da Segurança/organização & administração , Estados Unidos
20.
Eur J Orthop Surg Traumatol ; 28(3): 511-520, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29043506

RESUMO

Cephalomedullary nail (CMN) failure is a rare entity following hip fracture treatment. However, it poses significant challenges for revision surgery, both mechanically and biologically. Nail failure rates have been reported at < 2%; however, no published studies have reported revision surgery procedures and their respective outcomes. We present a regional experience, with outcomes, of the revision options. We identified 20 fatigued CMNs that underwent four different revision procedures. Mean age was 73 ± 15.24 years, with a 3:1 female preponderance, and a median ASA grade of 3. Post-operative CMN radiographs demonstrated a significant number of fractures were fixed in varus, with reductions in neck-shaft angles post-operatively. A "poor" quality of reduction resulted in significantly earlier nail failure, compared to "adequate" and "good" (p = 0.027). Tip-Apex Distance (TAD) mean was 23.2 ± 8.3 mm, and an adequate TAD with three-point fixation was seen in only 35% of cases. Mean time to failure was 401.0 ± 237.2 days, with mean age at failure of 74.0 ± 14.8 years. Options after failure included revision CMN nail, proximal femoral locking plate (PFLP), long-stem or restoration arthroplasty, or femoral endoprosthesis. Barthel Functional Index scores showed no significant difference at 3 and 12 months post-operatively, nor any difference between treatment groups. Mean 12-month mortality was 30%, akin to a primary hip fracture mortality risk according to NICE guidelines. Mortality rates were lowest in revision nails. Subsequent revision rates were higher in the PFLP group. There is no reported evidence on the best surgical technique for managing the failed CMN, with no clear functional benefit in the options above. Good surgical technique at the time of primary CMN surgery is critical in minimising fatigue failure. After revision, overall mortality rates were equivalent to reported primary hip fracture mortality rates. Further multicentre evaluations are required to assess which technique convey the best functional outcomes without compromising 12-month mortality rates.


Assuntos
Pinos Ortopédicos , Falha de Prótese , Idoso , Análise de Variância , Feminino , Fixação Intramedular de Fraturas/instrumentação , Consolidação da Fratura/fisiologia , Fraturas do Quadril/mortalidade , Fraturas do Quadril/cirurgia , Humanos , Masculino , Irlanda do Norte/epidemiologia , Estudos Prospectivos , Reoperação/estatística & dados numéricos , Estresse Mecânico , Fatores de Tempo , Resultado do Tratamento
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