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1.
Trauma Case Rep ; 42: 100717, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36281427

RESUMO

Scapular body fractures are rare fractures that represent less than 1 % of all fractures and are typically associated with a high energy mechanism of injury. Traditionally these fractures have been treated non-operatively, resulting in union of the fracture and acceptable patient outcomes. We present a case of symptomatic scapular body fracture nonunion following non-operative management that was treated with open reduction and internal fixation with local autologous bone grafting. Our patient went on to successful union of his fracture as well as drastic improvement in shoulder function, range of motion, strength, and patient reported outcome measures assessed throughout his treatment course. The authors believe that scapular body fracture nonunion should be of clinical suspicion in forming the differential diagnosis for a patient who had previously sustained a scapular body fracture with persistent pain and failure to improve following non-operative management. We believe that open reduction and internal fixation with bone grafting can help promote fracture union in these patients and may result in improved shoulder function post-operatively.

2.
Nat Commun ; 13(1): 4473, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918314

RESUMO

The discovery of two-dimensional systems hosting intrinsic magnetic order represents a seminal addition to the rich landscape of van der Waals materials. CrI3 is an archetypal example, where the interdependence of structure and magnetism, along with strong light-matter interactions, provides a new platform to explore the optical control of magnetic and vibrational degrees of freedom at the nanoscale. However, the nature of magneto-structural coupling on its intrinsic ultrafast timescale remains a crucial open question. Here, we probe magnetic and vibrational dynamics in bulk CrI3 using ultrafast optical spectroscopy, revealing spin-flip scattering-driven demagnetization and strong transient exchange-mediated interactions between lattice vibrations and spin oscillations. The latter yields a coherent spin-coupled phonon mode that is highly sensitive to the driving pulse's helicity in the magnetically ordered phase. Our results elucidate the nature of ultrafast spin-lattice coupling in CrI3 and highlight its potential for applications requiring high-speed control of magnetism at the nanoscale.

3.
Disabil Rehabil ; 44(10): 1889-1897, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32878485

RESUMO

PURPOSE: To develop a consensus statement for the prescription of a Powered Wheelchair Standing Device (PWSD) in young people with Duchenne muscular dystrophy (DMD). MATERIALS AND METHODS: An international multidisciplinary panel comprising clinicians and users (young people with DMD) along with their parents was consulted. A literature review was undertaken and a Delphi method was utilised to generate consensus statements. To supplement limited literature, round one of the Delphi process comprised questions consistent with the International Classification of Functioning, Disability and Health model of disability to generate items based on expert opinion and was completed by 38 clinicians and nine users. Thirty-seven participants completed two further rounds rating the importance of each item with a five-point scale. Agreement of 70% or more participants for items indicated consensus. RESULTS: Consensus was reached for 47 of 80 items. Tolerance and comfort in supported standing for at least 10 min, ankle contracture less than 10 degrees and user goals reflecting motivation to use the standing function were agreed as necessary in guiding the decision to trial a PWSD. Evidence of family, therapist and servicing support were also considered critical in enabling continuity of PWSD use. CONCLUSIONS: PWSD is a mobility option that offers choice, control and opportunity for independence. This consensus statement can assist clinicians with decision-making around factors influencing successful implementation and optimisation of PWSD for young people with DMD.Implications for RehabilitationTolerance and comfort in supported standing for at least 10 minutes, ankle contracture limited to less than 10 degrees and the child's goals reflecting motivation to use the standing position were agreed to be necessary considerations in guiding the decision to trial a PWSD.Trialling a PWSD when the child is predicted to lose the ability to walk within a one to two year period was recommended although a PWSD could be suitable for a child who was unable to walk.Evidence of family, therapist and servicing support was considered critical in enabling continuity of PWSD use.


Assuntos
Contratura , Distrofia Muscular de Duchenne , Cadeiras de Rodas , Adolescente , Criança , Técnica Delfos , Humanos , Prescrições , Posição Ortostática
4.
J Dairy Sci ; 103(8): 7322-7330, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32534929

RESUMO

The aim of this study was to evaluate the effect of sampling technique and milk fraction on bovine milk microbiota data and to compare the microbiota in milk to microbiota on the teat end and in the teat canal. Representative milk samples are highly important for assessment of bacteriological findings and microbiota in milk. Samples were obtained from 5 healthy lactating dairy cows at udder quarter level during 1 milking. Swab samples from the teat end and teat canal, and milk samples collected using different techniques and in different milk fractions were included. Milk was collected by hand stripping and through a teat canal cannula before and after machine milking, through a trans-teat wall needle aspirate after milking, and from udder quarter composite milk. The microbiota of the samples was analyzed with sequencing of the V1-V3 region of the 16S rRNA gene. In addition, somatic cell counts and bacterial cultivability were analyzed in the milk samples. Microbiota data were analyzed using multivariate methods, and differences between samples were tested using analysis of similarity (ANOSIM). Differences between samples were further explored via individual studies of the 10 most abundant genera. The microbiota on the teat end, in the teat canal, and in udder quarter composite milk, collected using a milking machine, differed in composition from the microbiota in milk collected directly from the udder quarter. No differences in milk microbiota composition were detected between hand-stripped milk samples, milk samples taken through a teat canal cannula, or milk samples taken as a trans-teat wall needle aspirate before or after milking. We conclude that for aseptic milk samples collected directly from the lactating udder quarter, sampling technique or milk fraction has minor effect on the microbiota composition.


Assuntos
Bactérias/isolamento & purificação , Bovinos/microbiologia , Microbiota , Leite/microbiologia , Manejo de Espécimes/veterinária , Animais , Bactérias/genética , Indústria de Laticínios , Feminino , Lactação , Glândulas Mamárias Animais/microbiologia , Pele/microbiologia
5.
Can Commun Dis Rep ; 45(2-3): 67-74, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31015821

RESUMO

BACKGROUND: Tuberculosis (TB) is a major global health problem that affected an estimated 10 million people worldwide in 2017. The Public Health Agency of Canada monitors active TB disease through a national surveillance system, which is a collaborative effort with the provinces and territories. OBJECTIVE: To present an epidemiological summary of active TB cases reported in 2017. Results are discussed in the context of the previous year's data. Treatment outcomes for cases diagnosed in 2016 are also presented. METHODS: The Canadian Tuberculosis Reporting System is a case-based surveillance system that maintains non-nominal data on people diagnosed with active TB disease in Canada. Data are collected annually from the provinces and territories, analyzed by the Public Health Agency of Canada and validated by each province and territory. RESULTS: There were 1,796 cases of active TB reported in Canada in 2017 compared with 1,750 cases in 2016, representing a 2.6% increase. There was a corresponding increase in the incidence rate from 4.8 to 4.9 per 100,000 population. Foreign born individuals continued to make up the majority of cases (71.8%) and the incidence rate remained highest among Canadian born Indigenous people (21.5 per 100,000 population), in particular, among the Inuit population (205.8 per 100,000 population). Consistent with the previous decade, TB incidence rates in 2017 continued to be higher among males (5.5 per 100,000) compared with females (4.3 per 100,000), and the majority of cases (45.6%) were between the ages of 15 and 44 years. The incidence rate was highest among adults over 75 years of age (13.8 cases per 100,000 for males and 7.2 for females). Of the TB cases diagnosed in 2016 where outcomes were reported, 80.4% were treated successfully. CONCLUSION: Although the incidence rate of TB in Canada in 2017 remained low in the global context and has been relatively stable over the last decade, both the case count and rate have been gradually increasing since 2014. Indigenous and foreign born Canadians continued to be disproportionately represented among TB cases. Canadian TB surveillance data are an important source of information for monitoring progress and informing public health action related to reducing the burden of TB in Canada, with the ultimate goal of TB elimination.

6.
J Dairy Sci ; 101(7): 6296-6309, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29729920

RESUMO

Staphylococcus aureus is an opportunistic pathogen affecting both human and animal species. An effective vaccine to prevent S. aureus bovine disease and transmission would have positive effects on animal well-being, food production, and human health. The objective of this study was to identify multiple antigens that are immunoreactive during udder colonization and disease for exploration as vaccine antigens to prevent bovine mastitis. Staphylococcus aureus produces several cell wall-anchored and surface-associated virulence factors that play key roles in the pathogenesis of mastitis. Many of these proteins are conserved between different strains of S. aureus and represent promising vaccine candidates. We used an immunoproteomics approach to identify antigenic proteins from the surface of S. aureus. The expression of cell wall and surface proteins from S. aureus was induced under low iron conditions, followed by trypsin extraction and separation by 2-dimensional electrophoresis. The separated proteins were blotted with antibodies from mastitic bovine milk and identified by liquid chromatography-mass spectrometry. Thirty-eight unique proteins were identified, of which 8 were predicted to be surface exposed and involved in S. aureus virulence. Two surface proteins, iron-regulated surface determinant protein C (IsdC) and ESAT-6 secretion system extracellular protein (EsxA), were cloned, expressed, and purified from Escherichia coli for confirmation of immune reactivity by ELISA. A PCR of 37 bovine S. aureus isolates indicated that the presence of esxA and isdC is conserved, and amino acid alignments revealed that IsdC and EsxA sequences are highly conserved. The immunoproteomics technique used in this study generated reproducible results and identified surface exposed and reactive antigens for further characterization.


Assuntos
Antígenos de Bactérias/imunologia , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/imunologia , Vacinação/veterinária , Animais , Bovinos , Feminino , Mastite Bovina/prevenção & controle , Leite , Staphylococcus aureus/patogenicidade
7.
Vaccine ; 36(24): 3513-3521, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29739718

RESUMO

Staphylococcus aureus causes a chronic, contagious disease of the udder, or mastitis, in dairy cows. This infection is often refractory to antibiotic treatment, and has a significant economic impact on milk production worldwide. An effective vaccine to prevent S. aureus mastitis would improve animal health, reduce antibiotic dependence and inform human vaccine approaches. The iron-regulated surface determinant A (IsdA) and clumping factor A (ClfA) are conserved S. aureus extracellular-matrix adhesins and target vaccine antigens. Here we report the results of two bovine immunogenicity trials using purified IsdA and ClfA-cholera toxin A2/B chimeras (IsdA-CTA2/B and ClfA-CTA2/B). Cows were intranasally inoculated with IsdA-CTA2/B + ClfA-CTA2/B at dry off and followed for 70 days. Trial 1 utilized three groups with one or two booster doses at a total concentration of 600 or 900 µg. Trial 2 utilized two groups with one booster at a total concentration of 1200 µg. Humoral immune responses in serum and milk were examined by ELISA. Responses in serum were significant between groups and provide evidence of antigen-specific IgG induction after vaccination in both trials. Cellular proliferation was detected by flow cytometry using antigen-stimulated PBMCs from day 60 of Trial 2 and revealed an increase in CD4+ T cells from vaccinated cows. IsdA and ClfA stimulation induced IL-4 expression, but not IFN-γ or IL-17, in PBMCs from day 60 as determined by cytokine expression analysis. Opsonophagocytosis of S. aureus confirmed the functional in vitro activity of anti-IsdA antibodies from Trial 2 serum and milk. The vaccine was well tolerated and safe, and results support the potential of mucosally-delivered CTA2/B chimeras to protect cows from mastitis caused by S. aureus.


Assuntos
Anticorpos Antibacterianos/biossíntese , Mastite Bovina/prevenção & controle , Proteínas Recombinantes de Fusão/imunologia , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/veterinária , Vacinas Antiestafilocócicas/biossíntese , Administração Intranasal , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Bovinos , Proliferação de Células/efeitos dos fármacos , Toxina da Cólera/administração & dosagem , Toxina da Cólera/genética , Toxina da Cólera/imunologia , Coagulase/administração & dosagem , Coagulase/genética , Coagulase/imunologia , Feminino , Expressão Gênica , Imunidade Humoral/efeitos dos fármacos , Imunização Secundária/métodos , Imunogenicidade da Vacina , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Interleucina-4/biossíntese , Interleucina-4/metabolismo , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Leite/química , Leite/imunologia , Leite/microbiologia , Isoformas de Proteínas/administração & dosagem , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Vacinas Antiestafilocócicas/administração & dosagem , Vacinas Antiestafilocócicas/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/imunologia , Staphylococcus aureus/patogenicidade
8.
Oncogene ; 37(6): 722-731, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29059175

RESUMO

Anti-vascular endothelial growth factor (VEGF) therapy has demonstrated efficacy in treating human metastatic cancers, but therapeutic resistance is a practical limitation and most tumors eventually become unresponsive. To identify microenvironmental factors underlying the resistance of cancer to antiangiogenesis therapy, we conducted genomic analyses of intraperitoneal ovarian tumors in which adaptive resistance to anti-VEGF therapy (B20 antibody) developed. We found that expression of the microseminoprotein, prostate-associated (MSMP) gene was substantially upregulated in resistant compared with control tumors. MSMP secretion from cancer cells was induced by hypoxia, triggering MAPK signaling in endothelial cells to promote tube formation in vitro. Recruitment of the transcriptional repressor CCCTC-binding factor (CTCF) to the MSMP enhancer region was decreased by histone acetylation under hypoxic conditions in cancer cells. MSMP siRNA, delivered in vivo using the DOPC nanoliposomes, restored tumor sensitivity to anti-VEGF therapy. In ovarian cancer patients treated with bevacizumab, serum MSMP concentration increased significantly only in non-responders. These findings imply that MSMP inhibition combined with the use of antiangiogenesis drugs may be a new strategy to overcome resistance to antiangiogenesis therapy.


Assuntos
Bevacizumab/farmacologia , Carcinoma Epitelial do Ovário/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias das Tubas Uterinas/patologia , Proteínas de Neoplasias/metabolismo , Neoplasias Peritoneais/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Animais , Apoptose , Biomarcadores Tumorais , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/metabolismo , Hipóxia Celular , Proliferação de Células , Neoplasias das Tubas Uterinas/tratamento farmacológico , Neoplasias das Tubas Uterinas/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Neovascularização Patológica , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/metabolismo , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Ir J Med Sci ; 187(1): 123-126, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28474237

RESUMO

BACKGROUND: National guidelines have been developed to ensure correct dosing of tinzaparin for women delivered by caesarean delivery (CD) to reduce the risk of venous thromboembolism. AIMS: The aim of this study is to examine the impact of implementation of national guidelines on thromboprophylaxis prescribing practice for women undergoing CD in a university maternity hospital. METHODS: Details of tinzaparin usage were obtained from the Hospital pharmacy for the years 2009-2014. Information on CD and pulmonary embolism (PE) were obtained from the Hospital's annual clinical reports. RESULTS: Following guideline recommendations on weight-based tinzaparin for all women undergoing CD, the usage of syringes prefilled with tinzaparin 4500 IU increased from 526 to 8502 (P < 0.001) and usage of syringes prefilled with tinzaparin 10,000 IU increased from 36 to 910 (P < 0.001). Usage of syringes prefilled with tinzaparin 3500 IU decreased from 8216 in 2009 to 39 in 2014 (P < 0.001). During 2008-2010, there were two cases of PE after CD, both of whom received an inadequate dose of prophylactic tinzaparin. During 2011-2014 there were no cases of PE diagnosed after a total of 9427 CDs. CONCLUSIONS: The development of national guidelines on thromboprophylaxis after CD was followed by a significant change in weight-based prescribing of tinzaparin. Following implementation, there have been no cases of PE after CD.


Assuntos
Cesárea/efeitos adversos , Fibrinolíticos/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Embolia Pulmonar/tratamento farmacológico , Tromboembolia Venosa/tratamento farmacológico , Cesárea/métodos , Feminino , Fibrinolíticos/farmacologia , Heparina de Baixo Peso Molecular/farmacologia , História do Século XXI , Humanos , Pessoa de Meia-Idade , Gravidez , Embolia Pulmonar/patologia , Tinzaparina , Tromboembolia Venosa/patologia
10.
Can Commun Dis Rep ; 44(12): 348-356, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30906230

RESUMO

BACKGROUND: Human immunodeficiency virus (HIV) is a global public health issue with an estimated 1.8 million people newly infected in 2017. OBJECTIVE: To provide a descriptive overview of reported cases of HIV in Canada by geographic location, sex, age group, exposure category and race/ethnicity, from 1985-2017, with a focus on the most recent data. METHODS: The Public Health Agency of Canada (PHAC) monitors HIV through the national HIV/AIDS Surveillance System, which is a passive, case-based system that collates non-nominal data voluntarily submitted and validated by all Canadian provinces and territories. Additional data sources presented here include data on immigration-related medical screening for HIV by Immigration, Refugees and Citizenship Canada and data on infants perinatally-exposed to HIV submitted by the Canadian Perinatal HIV Surveillance Program. Data were collated, tables and figures were prepared and descriptive statistics were applied by PHAC and validated by each province and territory. RESULTS: A total of 2,402 new HIV diagnoses were reported in 2017 in Canada; an increase of 3% compared with 2016 and an increase of 17.1% since 2014. The national diagnosis rate increased slightly, from 6.4 per 100,000 population in 2016 to 6.5 per 100,000 population in 2017. In 2017, while Ontario continued to account for the highest number (n=935) and proportion (38.9%) of reported HIV cases, Saskatchewan reported the highest provincial diagnosis rate (15.5 per 100,000 population). In 2017, the diagnostic rate for males at 9.9 per 100,000 population was higher than for females at 3.2 per 100,000 population. As in 2016, the 30-39 year age group had the highest HIV diagnosis rate at 14.8 per 100,000 population. The "gay, bisexual and other men who have sex with men" exposure category continued to represent almost half (46.4%) of all reported HIV cases in adults. In 2017, the absolute number of HIV-positive migrants entering Canada increased to a total number of 835 migrants. One mother-to-child HIV transmission was confirmed in a mother who did not receive any perinatal antiretroviral therapy and two transmissions were confirmed in mothers who did receive perinatal antiretroviral therapy. CONCLUSION: Similar to the annual changes that have been reported since 2014, the number and rate of reported HIV cases in Canada in 2017 increased slightly compared with 2016. Additional data and analysis are needed to determine the extent to which these findings reflect an increase in HIV transmission, an increase in HIV testing, changes in reporting practices and an increase in the number of HIV-positive people migrating to Canada.

11.
Appl Microbiol Biotechnol ; 101(2): 797-808, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27785541

RESUMO

The microbial potential for toluene degradation within sediments from a tar oil-contaminated site in Flingern, Germany, was assessed using a metagenomic approach. High molecular weight environmental DNA from contaminated sediments was extracted, purified, and cloned into fosmid and BAC vectors and transformed into Escherichia coli. The fosmid library was screened by hybridization with a PCR amplicon of the α-subunit of the toluene 4-monooxygenase gene to identify genes and pathways encoding toluene degradation. Fourteen clones were recovered from the fosmid library, among which 13 were highly divergent from known tmoA genes and several had the closest relatives among Acinetobacter species. The BAC library was transferred to the heterologous hosts Cupriavidus metallidurans (phylum Proteobacteria) and Edaphobacter aggregans (phylum Acidobacteria). The resulting libraries were screened for expression of toluene degradation in the non-degradative hosts. From expression in C. metallidurans, three novel toluene monooxygenase-encoding operons were identified that were located on IncP1 plasmids. The E. aggregans-hosted BAC library led to the isolation of a cloned genetic locus putatively derived from an Acidobacteria taxon that contained genes involved in aerobic and anaerobic toluene degradation. These data suggest the important role of plasmids in the spread of toluene degradative capacity and indicate putative novel tmoA genes present in this hydrocarbon-polluted environment.


Assuntos
Microbiologia Ambiental , Poluentes Ambientais/metabolismo , Oxigenases de Função Mista/análise , Oxigenases de Função Mista/genética , Tolueno/metabolismo , Clonagem Molecular , Testes Genéticos , Alemanha , Metagenômica , Hibridização de Ácido Nucleico , Análise de Sequência de DNA
12.
Can Commun Dis Rep ; 43(3-4): 77-82, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29770069

RESUMO

BACKGROUND: Tuberculosis (TB) is a global health problem that affects an estimated 10 million people each year. In Canada, the Public Health Agency of Canada (PHAC) monitors active TB disease through the Canadian Tuberculosis Reporting System (CTBRS). OBJECTIVE: To report on and analyze the number of new and re-treatment cases of TB cases in Canada reported for 2015. Results are discussed in the context of previous year's data. Treatment outcomes for cases diagnosed in 2014 are also presented. METHODS: The CTBRS is a case-based surveillance system that maintains non-nominal data on active cases of TB. Data are collected and analyzed by PHAC and validated by each province and territory; no statistical tests were used. RESULTS: A total of 1,639 cases of active TB disease were reported in 2015, representing a slight increase from the number of cases reported in 2014 (1,614) and a corresponding increase in the incidence rate from 4.5 per 100,000 to 4.6 per 100,000 population. Although the incidence rate of TB remained highest in Nunavut at 119.2 per 100,000 population in 2015, it was nearly half of what it was in 2014. An outbreak in Newfoundland and Labrador resulted in a notable increase in the number of reported cases and incidence rate in this province. In 2015, males accounted for just over half of the reported cases at 53% and older Canadians carried the highest burden of TB with an incidence rate of 10.3 per 100,000 population. Foreign-born individuals continued to account for the majority of reported cases at 71%, but the incidence rate remained highest among Canadian-born Indigenous people at 17.1 per 100,000 population and in particular within the Inuit population at 166.2 per 100,000. Pulmonary TB remained the most commonly reported site of disease. Treatment outcome data for cases reported in 2014 indicated that 85% of cases had been cured or had completed treatment. CONCLUSION: Tuberculosis rates in Canada have changed little over the last decade and overall, remain stable and low in the global context. However, foreign-born individuals and Indigenous Canadians continued to be disproportionately represented among reported cases of TB in 2015. As the primary source of national data on TB cases, the data within this report provide timely information for public health action, as well as policy and program development and assessment.

13.
Phys Rev Lett ; 117(23): 235701, 2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27982606

RESUMO

The structural properties of LaCu_{6-x}Au_{x} are studied using neutron diffraction, x-ray diffraction, and heat capacity measurements. The continuous orthorhombic-monoclinic structural phase transition in LaCu_{6} is suppressed linearly with Au substitution until a complete suppression of the structural phase transition occurs at the critical composition x_{c}=0.3. Heat capacity measurements at low temperatures indicate residual structural instability at x_{c}. The instability is ferroelastic in nature, with density functional theory calculations showing negligible coupling to electronic states near the Fermi level. The data and calculations presented here are consistent with the zero temperature termination of a continuous structural phase transition suggesting that the LaCu_{6-x}Au_{x} series hosts an elastic quantum critical point.

14.
Phys Rev Lett ; 117(17): 176603, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27824456

RESUMO

The perovskite SrIrO_{3} is an exotic narrow-band metal owing to a confluence of the strengths of the spin-orbit coupling (SOC) and the electron-electron correlations. It has been proposed that topological and magnetic insulating phases can be achieved by tuning the SOC, Hubbard interactions, and/or lattice symmetry. Here, we report that the substitution of nonmagnetic, isovalent Sn^{4+} for Ir^{4+} in the SrIr_{1-x}Sn_{x}O_{3} perovskites synthesized under high pressure leads to a metal-insulator transition to an antiferromagnetic (AF) phase at T_{N}≥225 K. The continuous change of the cell volume as detected by x-ray diffraction and the λ-shape transition of the specific heat on cooling through T_{N} demonstrate that the metal-insulator transition is of second order. Neutron powder diffraction results indicate that the Sn substitution enlarges an octahedral-site distortion that reduces the SOC relative to the spin-spin exchange interaction and results in the type-G AF spin ordering below T_{N}. Measurement of high-temperature magnetic susceptibility shows the evolution of magnetic coupling in the paramagnetic phase typical of weak itinerant-electron magnetism in the Sn-substituted samples. A reduced structural symmetry in the magnetically ordered phase leads to an electron gap opening at the Brillouin zone boundary below T_{N} in the same way as proposed by Slater.

15.
J Dent Res ; 95(5): 523-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26908630

RESUMO

Biological mediators have been used to enhance periodontal regeneration. The aim of this prospective randomized controlled study was to evaluate the safety and effectiveness of 3 doses of fibroblast growth factor 2 (FGF-2) when combined with a ß-tricalcium phosphate (ß-TCP) scaffold carrier placed in vertical infrabony periodontal defects in adult patients. In this double-blinded, dose-verification, externally monitored clinical study, 88 patients who required surgical intervention to treat a qualifying infrabony periodontal defect were randomized to 1 of 4 treatment groups-ß-TCP alone (control) and 0.1% recombinant human FGF-2 (rh-FGF-2), 0.3% rh-FGF-2, and 0.4% rh-FGF-2 with ß-TCP-following scaling and root planing of the tooth prior to a surgical appointment. Flap surgery was performed with EDTA conditioning of the root prior to device implantation. There were no statistically significant differences in patient demographics and baseline characteristics among the 4 treatment groups. When a composite outcome of gain in clinical attachment of 1.5 mm was used with a linear bone growth of 2.5 mm, a dose response pattern detected a plateau in the 0.3% and 0.4% rh-FGF-2/ß-TCP groups with significant improvements over control and 0.1% rh-FGF-2/ß-TCP groups. The success rate at 6 mo was 71% in the 2 higher-concentration groups, as compared with 45% in the control and lowest treatment groups. Percentage bone fill in the 2 higher-concentration groups was 75% and 71%, compared with 63% and 61% in the control and lowest treatment group. No increases in specific antibody to rh-FGF-2 were detected, and no serious adverse events related to the products were reported. The results from this multicenter trial demonstrated that the treatment of infrabony vertical periodontal defects can be enhanced with the addition of rh-FGF-2/ß-TCP (ClinicalTrials.gov NCT01728844).


Assuntos
Perda do Osso Alveolar/cirurgia , Substitutos Ósseos/uso terapêutico , Fosfatos de Cálcio/uso terapêutico , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Adulto , Idoso , Perda do Osso Alveolar/tratamento farmacológico , Raspagem Dentária/métodos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Seguimentos , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Perda da Inserção Periodontal/tratamento farmacológico , Perda da Inserção Periodontal/cirurgia , Estudos Prospectivos , Proteínas Recombinantes , Aplainamento Radicular/métodos , Segurança , Retalhos Cirúrgicos/cirurgia , Tecidos Suporte , Resultado do Tratamento
16.
Oncogene ; 35(33): 4312-20, 2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-26725326

RESUMO

MicroRNAs (miRNAs) are small RNA molecules that affect cellular processes by controlling gene expression. Recent studies have shown that hypoxia downregulates Drosha and Dicer, key enzymes in miRNA biogenesis, causing a decreased pool of miRNAs in cancer and resulting in increased tumor growth and metastasis. Here we demonstrate a previously unrecognized mechanism by which hypoxia downregulates Dicer. We found that miR-630, which is upregulated under hypoxic conditions, targets and downregulates Dicer expression. In an orthotopic mouse model of ovarian cancer, delivery of miR-630 using 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nanoliposomes resulted in increased tumor growth and metastasis, and decreased Dicer expression. Treatment with the combination of anti-miR-630 and anti-vascular endothelial growth factor antibody in mice resulted in rescue of Dicer expression and significantly decreased tumor growth and metastasis. These results indicate that targeting miR-630 is a promising approach to overcome Dicer deregulation in cancer. As demonstrated in the study, use of DOPC nanoliposomes for anti-miR delivery serves as a better alternative approach to cell line-based overexpression of sense or antisense miRNAs, while avoiding potential in vitro selection effects. Findings from this study provide a new understanding of miRNA biogenesis downregulation observed under hypoxia and suggest therapeutic avenues to target this dysregulation in cancer.


Assuntos
Hipóxia Celular , RNA Helicases DEAD-box/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , Neoplasias/etiologia , Ribonuclease III/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Lipossomos , Camundongos , MicroRNAs/antagonistas & inibidores , Neoplasias/terapia , Neoplasias Ovarianas/metabolismo , Fosfatidilcolinas/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
17.
Can Commun Dis Rep ; 41(Suppl 2): 8-15, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-31713535

RESUMO

BACKGROUND: Drug-resistant strains of tuberculosis (TB) pose a serious threat to prevention and control efforts. In response to this growing worldwide concern, the Public Health Agency of Canada (PHAC) established and maintains the Canadian Tuberculosis Laboratory Surveillance System (CTBLSS) in partnership with the Canadian Tuberculosis Laboratory Technical Network (CTLTN) and participating laboratories. OBJECTIVE: To report on national trends and patterns in anti-tuberculosis drug resistance in Canada for the years 2003 to 2013. METHOD: At the beginning of each calendar year, participating laboratories submit to PHAC reports on the results of anti-tuberculosis drug susceptibility testing for all isolates tested during the preceding year. These data are then analyzed by PHAC and the results are validated by supplying laboratories. The results are published annually as the Tuberculosis Drug Resistance in Canada series. RESULTS: In 2013, anti-tuberculosis drug susceptibility test results for 1,380 isolates were reported to PHAC. Of these, 762 (54%) were reported as Mycobacterium tuberculosis complex (MTBC) where the species was known. Two thirds (68%) of all the reported isolates originated from the three largest provinces, British Columbia, Ontario and Quebec. Overall, of the laboratory results received, 112 (8.1%) showed resistance to at least one first-line drug and, of these, the majority (93 or 83%) were monoresistant. CONCLUSION: TB drug resistance observed in Canada remains well below the global average. Over the last 10 years, the percentage of isolates with resistance to one or more of the first-line medications has decreased from 10.5% in 2003 to 8.1% in 2013.

18.
Can Commun Dis Rep ; 41(Suppl 2): 2-7, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-31713538

RESUMO

BACKGROUND: The Public Health Agency of Canada (PHAC) monitors active TB disease through the national collaborative Canadian Tuberculosis Reporting System (CTBRS). PHAC uses TB surveillance data and reports to monitor progress towards achieving Canada's goal of preventing and controlling the transmission of TB, as outlined in Tuberculosis Prevention and Control in Canada-A Federal Framework for Action. OBJECTIVE: To provide an overview of the preliminary number of reported active (new and re-treatment) TB cases and corresponding incidence rates in Canada for 2013. METHODS: Provincial and territorial public health authorities voluntarily submit data to the CTBRS on an annual basis for all TB cases that meet the case definition for national-level surveillance. These data are analyzed by PHAC; the results of the analysis are validated by the supplying jurisdiction and are published annually as the Tuberculosis in Canada Pre-release series. RESULTS: In Canada, 1,640 new active and re-treatment TB cases were reported in 2013 for an overall incidence rate of 4.7 per 100,000 population. There was little change from preceding years in the overall distribution of cases by sex and age group. Although individuals aged 25 to 34 years old represented the largest percentage of reported cases (16%), the highest incidence rate was observed for those aged 75 years or older. Incidence rates in British Columbia, Manitoba, Saskatchewan, Nunavut, and Northwest Territories were higher than the Canadian rate, with Nunavut showing the highest incidence rate. Foreign-born individuals continue to account for the majority of reported TB cases, but the incidence rate per 100,000 population remains highest among Canadian-born Aboriginal people. CONCLUSION: Preliminary data from 2013 indicate that there were no notable changes in the number of reported cases of TB or in the overall incidence rate in Canada when compared with previous years' data. Similarly, no changes were noted in the distribution of cases by province or territory, age group or sex.

20.
Phys Rev Lett ; 113(14): 147601, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25325660

RESUMO

We measured nuclear forward scattering spectra utilizing the (99)Ru transition, 89.571(3) keV, with a notably mixed E2/M1 multipolarity. The extension of the standard evaluation routines to include mixed multipolarity allows us to extract electric and magnetic hyperfine interactions from (99)Ru-containing compounds. This paves the way for several other high-energy Mössbauer transitions, E ∼ 90 keV. The high energy of such transitions allows for operando nuclear forward scattering studies in real devices.

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