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1.
Genes Dev ; 29(5): 526-37, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25691092

RESUMO

RNAi is a conserved genome defense mechanism in eukaryotes that protects against deleterious effects of transposons and viral invasion. Repetitive DNA loci are a major source for the production of eukaryotic small RNAs, but how these small RNAs are produced is not clear. Quelling in Neurospora is one of the first known RNAi-related phenomena and is triggered by the presence of multiple copies of transgenes. Here we showed that DNA tandem repeats and double-strand breaks are necessary and, when both are present, sufficient to trigger gene silencing and siRNA production. Introduction of a site-specific double-strand break or DNA fragile site resulted in homologous recombination of repetitive sequences, which is required for gene silencing. In addition to siRNA production, the quelling pathway also maintains tandem repeats by regulating homologous recombination. Our study identified the mechanistic trigger for siRNA production from repetitive DNA and established a role for siRNA in maintaining genome stability.


Assuntos
DNA Fúngico/genética , Neurospora/genética , RNA Interferente Pequeno/biossíntese , Sequências Repetitivas de Ácido Nucleico/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Inativação Gênica , Genoma Fúngico/genética , Mutação , RNA Interferente Pequeno/genética
2.
Microb Cell Fact ; 20(1): 91, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902585

RESUMO

BACKGROUND: Protein synthesis is one of the extremely important anabolic pathways in the yeast expression system Pichia pastoris. Codon optimization is a commonly adopted strategy for improved protein expression, although unexpected failures did appear sometimes waiting for further exploration. Recently codon bias has been studied to regulate protein folding and activity in many other organisms. RESULTS: Here the codon bias profile of P. pastoris genome was examined first and a direct correlation between codon translation efficiency and usage frequency was identified. By manipulating the codon choices of both endogenous and heterologous signal peptides, secretion abilities of N-terminal signal peptides were shown to be tolerant towards codon changes. Then two gene candidates with different levels of structural disorder were studied, and full-length codon optimization was found to affect their expression profiles differentially. Finally, more evidences were provided to support possible protein conformation change brought by codon optimization in structurally disordered proteins. CONCLUSION: Our results suggest that codon bias regulates gene expression by modulating several factors including transcription and translation efficiency, protein folding and activity. Because of sequences difference, the extent of affection may be gene specific. For some genes, special codon optimization strategy should be adopted to ensure appropriate expression and conformation.


Assuntos
Engenharia Genética/métodos , Proteínas Recombinantes/biossíntese , Saccharomycetales , Códon , Uso do Códon , Expressão Gênica , Conformação Proteica , Dobramento de Proteína , Saccharomycetales/genética , Saccharomycetales/metabolismo
3.
Environ Sci Technol ; 54(23): 14830-14842, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31961669

RESUMO

China has set high water-conservation, energy-saving, and pollutant-reduction goals for the petrochemical industry. This represents a challenge to petrochemical enterprises because of the complex coupling between water, energy, and environmental pollutant (WEE) subsystems, elements (different types of WEE), and production units. However, there has been little research on the element-level coupling relationship. The connection and difference between the coupling relationships of the system, element, and unit levels are not well understood. Therefore, an integrated analysis method was developed to quantify the petrochemical WEE nexus (WEEN) at these three levels, including a generic WEEN model, material and energy flow analysis, and a WEEN analysis matrix. Three indicators were proposed to analyze three-level coupling quantitatively and to formulate improvement strategies for water-conservation, energy-saving, and pollutant-reduction. A case study demonstrated significant three-level coupling. The coupled percentage of WEE subsystems were 95.87%, 61.97%, and 54.99%, respectively. The dominant energy subsystem was the root of high consumption and pollution. Based on synergies and trade-offs, we proposed element optimization priorities: High priority (deoxidized water and fuel), medium priority (steam, circulating water, and wastewater), and low priority (fresh water, demineralized water, waste gas, and electricity). The identified unit improvement potential revealed overestimation (hydrotreating and delayed coking units) and underestimation (crude distillation units) of conventional methods that overlook three-level coupling.


Assuntos
Poluentes Ambientais , Água , China , Indústrias , Águas Residuárias
4.
PLoS Genet ; 9(1): e1003227, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23349642

RESUMO

Most plant and animal microRNAs (miRNAs) are transcribed by RNA polymerase II. We previously discovered miRNA-like small RNAs (milRNAs) in the filamentous fungus Neurospora crassa and uncovered at least four different pathways for milRNA production. To understand the evolutionary origin of milRNAs, we determined the roles of polymerases II and III (Pol II and Pol III) in milRNA transcription. Our results show that Pol III is responsible for the transcription of the major milRNAs produced in this organism. The inhibition of Pol III activity by an inhibitor or by gene silencing abolishes the production of most abundant milRNAs and pri-milRNAs. In addition, Pol III associates with these milRNA producing loci. Even though silencing of Pol II does not affect the synthesis of the most abundant milRNAs, Pol II or both Pol II and Pol III are associated with some milRNA-producing loci, suggesting a regulatory interaction between the two polymerases for some milRNA transcription. Furthermore, we show that one of the Pol III-transcribed milRNAs is derived from a tRNA precursor, and its biogenesis requires RNase Z, which cleaves the tRNA moiety to generate pre-milRNA. Our study identifies the transcriptional machinery responsible for the synthesis of fungal milRNAs and sheds light on the evolutionary origin of eukaryotic small RNAs.


Assuntos
MicroRNAs , Neurospora crassa , RNA Polimerase III , RNA Polimerase II , RNA Fúngico , Sequência de Bases , Endorribonucleases/genética , Regulação Fúngica da Expressão Gênica , Inativação Gênica , MicroRNAs/biossíntese , MicroRNAs/genética , MicroRNAs/metabolismo , Dados de Sequência Molecular , Neurospora crassa/enzimologia , Neurospora crassa/genética , Regiões Promotoras Genéticas , RNA Polimerase II/antagonistas & inibidores , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA Polimerase III/genética , RNA Polimerase III/metabolismo , RNA Fúngico/genética
5.
J Biol Chem ; 289(13): 9365-71, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24554705

RESUMO

Quelling and DNA damage-induced small RNA (qiRNA) production are RNA interference (RNAi)-related phenomenon from repetitive genomic loci in Neurospora. We have recently proposed that homologous recombination from repetitive DNA loci allows the RNAi pathway to recognize repetitive DNA to produce small RNA. However, the mechanistic detail of this pathway remains largely unclear. By systematically screening the Neurospora knock-out library, we identified RTT109 as a novel component required for small RNA production. RTT109 is a histone acetyltransferase for histone H3 lysine 56 (H3K56) and H3K56 acetylation is essential for the small RNA biogenesis pathway. Furthermore, we showed that RTT109 is required for homologous recombination and H3K56Ac is enriched around double strand break, which overlaps with RAD51 binding. Taken together, our results suggest that H3K56 acetylation is required for small RNA production through its role in homologous recombination.


Assuntos
Histonas/química , Histonas/metabolismo , Recombinação Homóloga/genética , Lisina/metabolismo , Interferência de RNA , RNA Interferente Pequeno/biossíntese , RNA Interferente Pequeno/genética , Acetilação , Técnicas de Inativação de Genes , Histona Acetiltransferases/química , Histona Acetiltransferases/deficiência , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Neurospora crassa/enzimologia , Neurospora crassa/genética , Neurospora crassa/metabolismo
6.
Plant Physiol ; 166(2): 869-78, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25118256

RESUMO

Alternative splicing is an essential biological process to generate proteome diversity and phenotypic complexity. Recent improvements in RNA sequencing accuracy and computational algorithms have provided unprecedented opportunities to examine the expression levels of Arabidopsis (Arabidopsis thaliana) transcripts. In this article, we analyzed 61 RNA sequencing samples from 10 totally independent studies of Arabidopsis and calculated the transcript expression levels in different tissues, treatments, developmental stages, and varieties. These data provide a comprehensive profile of Arabidopsis transcripts with single-base resolution. We quantified the expression levels of 40,745 transcripts annotated in The Arabidopsis Information Resource 10, comprising 73% common transcripts, 15% rare transcripts, and 12% nondetectable transcripts. In addition, we investigated diverse common transcripts in detail, including ubiquitous transcripts, dominant/subordinate transcripts, and switch transcripts, in terms of their expression and transcript ratio. Interestingly, alternative splicing was the highly enriched function for the genes related to dominant/subordinate transcripts and switch transcripts. In addition, motif analysis revealed that TC motifs were enriched in dominant transcripts but not in subordinate transcripts. These motifs were found to have a strong relationship with transcription factor activity. Our results shed light on the complexity of alternative splicing and the diversity of the contributing factors.


Assuntos
Arabidopsis/genética , RNA Mensageiro/genética , RNA de Plantas/genética , Processamento Alternativo , Genes de Plantas
7.
Plant J ; 73(5): 747-60, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23134061

RESUMO

Rapid actin turnover is essential for numerous actin-based processes. However, how it is precisely regulated remains poorly understood. Actin-interacting protein 1 (AIP1) has been shown to be an important factor by acting coordinately with actin-depolymerizing factor (ADF)/cofilin in promoting actin depolymerization, the rate-limiting factor in actin turnover. However, the molecular mechanism by which AIP1 promotes actin turnover remains largely unknown in plants. Here, we provide a demonstration that AIP1 promotes actin turnover, which is required for optimal growth of rice plants. Specific down-regulation of OsAIP1 increased the level of filamentous actin and reduced actin turnover, whereas over-expression of OsAIP1 induced fragmentation and depolymerization of actin filaments and enhanced actin turnover. In vitro biochemical characterization showed that, although OsAIP1 alone does not affect actin dynamics, it enhances ADF-mediated actin depolymerization. It also caps the filament barbed end in the presence of ADF, but the capping activity is not required for their coordinated action. Real-time visualization of single filament dynamics showed that OsAIP1 enhanced ADF-mediated severing and dissociation of pointed end subunits. Consistent with this, the filament severing frequency and subunit off-rate were enhanced in OsAIP1 over-expressors but decreased in RNAi protoplasts. Importantly, OsAIP1 acts coordinately with ADF and profilin to induce massive net actin depolymerization, indicating that AIP1 plays a major role in the turnover of actin, which is required to optimize F-actin levels in plants.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas dos Microfilamentos/genética , Oryza/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Destrina/metabolismo , Regulação para Baixo , Expressão Gênica , Proteínas dos Microfilamentos/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oryza/ultraestrutura , Epiderme Vegetal/genética , Epiderme Vegetal/crescimento & desenvolvimento , Epiderme Vegetal/metabolismo , Epiderme Vegetal/ultraestrutura , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestrutura , Plantas Geneticamente Modificadas , Profilinas/metabolismo , Protoplastos , RNA de Plantas/genética , Proteínas Recombinantes , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Plântula/ultraestrutura , Imagem com Lapso de Tempo , Regulação para Cima
8.
Biomed Eng Online ; 13: 141, 2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25277489

RESUMO

PURPOSE: To diagnose pneumoconiosis using a computer-aided diagnosis system based on digital chest radiographs. METHODS: Lung fields were first extracted by combining the traditional Otsu-threshold method with a morphological reconstruction on digital radiographs (DRs), and then subdivided into six non-overlapping regions (region (a-f)). Twenty-two wavelet-based energy texture features were calculated exclusively from each region and selected using a decision tree algorithm. A support vector machine (SVM) with a linear kernel was trained using samples with texture features to classify an individual region of a healthy subject or a pneumoconiosis patient. The final classification results were obtained by integrating these individual classifiers with the weighted voting method. All models were developed on a dataset of 85 healthy controls and 40 stage I or II pneumoconiosis patients and validated by using the bootstrap resampling with replacement method. RESULTS: The areas under receiver operating characteristic curves (AUCs) of regions (c) and (f) were 0.688 and 0.563, which were worse than those of the other four regions. Region (c) and (f) were both excluded from the individual classifiers that were going to be assembled further. When built on the selected texture features, each individual SVM showed a higher diagnostic performance for the training set and the test set. The classification performance after an ensemble was 0.997 and 0.961 of the AUC value for the training and test sets, respectively. The final results were 0.974 ± 0.018 for AUC value and 0.929 ± 0.018 for accuracy. CONCLUSION: The integrated SVM model built on the selected feature set showed the highest diagnostic performance among all individual SVM models. The model has good potential in diagnosing pneumoconiosis based on digital chest radiographs.


Assuntos
Pulmão/diagnóstico por imagem , Pneumoconiose/diagnóstico por imagem , Pneumoconiose/diagnóstico , Radiografia Torácica/métodos , Idoso , Algoritmos , Área Sob a Curva , Estudos de Casos e Controles , Árvores de Decisões , Diagnóstico por Computador , Humanos , Modelos Lineares , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador , Máquina de Vetores de Suporte
9.
Artigo em Inglês | MEDLINE | ID: mdl-38923792

RESUMO

Fluorescence-related experimental techniques play an important role in biochemistry, molecular biology, and cell biology. However, fluorescence-related experiments are rarely included in the laboratory courses of most Chinese universities. This is mainly due to the conflict between large class size (50-60 students in one room) and funding/space limitations to purchase and accommodate enough fluorescence detection equipment. Here, we proposed feasible and economical Do It Yourself (DIY) procedures of a hand-held fluorescence detector set-FluorDetector to support the development of laboratory courses. Tested on several samples, clear fluorescence signals could be directly observed by FluorDetector and photographed with a smartphone. In addition, FluorDetector was able to turn a conventional stereomicroscope into a fluorescence stereomicroscope, detecting fluorescence signals with clean background. FluorDetector is easy to make with a 3D printer, with an extremely low cost ($200 each) when compared with a commercial fluorescence microscope or fluorescence stereomicroscope, and almost as sensitive as a microplate reader in measuring fluorescence. Therefore, FluorDetector is a possible strategy to solve the problem and help to integrate fluorescence-related experimental modules in laboratory courses.

10.
PLoS Biol ; 8(10)2010 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-20957187

RESUMO

The production of aberrant RNA (aRNA) is the initial step in several RNAi pathways. How aRNA is produced and specifically recognized by RNA-dependent RNA polymerases (RdRPs) to generate double-stranded RNA (dsRNA) is not clear. We previously showed that in the filamentous fungus Neurospora, the RdRP QDE-1 is required for rDNA-specific aRNA production, suggesting that QDE-1 may be important in aRNA synthesis. Here we show that a recombinant QDE-1 is both an RdRP and a DNA-dependent RNA polymerase (DdRP). Its DdRP activity is much more robust than the RdRP activity and occurs on ssDNA but not dsDNA templates. We further show that Replication Protein A (RPA), a single-stranded DNA-binding complex that interacts with QDE-1, is essential for aRNA production and gene silencing. In vitro reconstitution assays demonstrate that QDE-1 can produce dsRNA from ssDNA, a process that is strongly promoted by RPA. Furthermore, the interaction between QDE-1 and RPA requires the RecQ DNA helicase QDE-3, a homolog of the human Werner/Bloom Syndrome proteins. Together, these results suggest a novel small RNA biogenesis pathway in Neurospora and a new mechanism for the production of aRNA and dsRNA in RNAi pathways.


Assuntos
DNA Helicases/metabolismo , Proteínas Fúngicas/metabolismo , Interferência de RNA , RNA de Cadeia Dupla , RNA Polimerase Dependente de RNA/metabolismo , RNA , Proteína de Replicação A/metabolismo , Animais , DNA Helicases/genética , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Humanos , Neurospora crassa/genética , Neurospora crassa/metabolismo , RNA/genética , RNA/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , RNA Polimerase Dependente de RNA/genética , Proteína de Replicação A/genética , Ribonucleases/genética , Ribonucleases/metabolismo
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(12): 3293-7, 2013 Dec.
Artigo em Zh | MEDLINE | ID: mdl-24611389

RESUMO

In the history of Chinese pigment, copper green, a pigment, was used in vast territory and for a long time. In the present paper, the nature, spectral characteristics, thermodynamic stability of the four isomers of the basic copper chlorides and also their application in the polychrome relics were discussed. The four isomers can be identified quickly by Raman spectral analysis which is a micro-damage or even a nondestructive technique. The order of their thermodynamic stability is as follows: clinoatacamite>paratacamite>atacamite>botallackite. It was showed that in the relics samples copper green was mostly botallackite and atacamite which were less stable isomers. According to the Ostwald step rule, the environmental monitoring should be strengthened to prevent the change in their physical and chemical structures.

12.
Can Commun Dis Rep ; 49(11-12): 465-476, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38504876

RESUMO

Background: Gay or bisexual (GB) and other men who have sex with men (MSM) are disproportionately affected by human immunodeficiency virus (HIV) globally and domestically in Canada. Reliable and recent population size estimates are necessary to allocate resources to meet prevention needs and for modelling the HIV epidemic. However, previous direct estimates did not account for GB men who would not reveal their sexual identity to a government survey, nor MSM not identifying as GB. The objective of this study was to develop two national population size estimates of gay, bisexual and other men who have sex with men (gbMSM) in 2020. First, GB men based on identity, regardless of sexual experience, and MSM who do not identify as GB but reported anal sex with a man in the past 1-5 years ("Identity-or-Behaviour" estimate). Second, an estimate of gbMSM who reported past 6-12 months anal sex with a man ("Behaviour-only" estimate). Methods: Estimates for males aged 15 years and older were drawn from Statistics Canada's population size estimates, the Canadian Community Health Survey and the Community-Based Research Centre's Sex Now Survey. Estimated proportions of GB identity, those not likely to disclose GB identity and MSM who do not identify as GB but who reported past 1-5 years anal sex were applied. Past 6-12 months anal sex history was subsequently used to limit estimates to those sexually active anally. Results: It was estimated that 3.5% of the male population in Canada aged 15 years and older identified as GB. Of GB males, 86.5% were likely to disclose their sexual identity to a government survey. A further 0.1% of non-GB identified males reported past year anal sex with a man. The national Identity-or-Behaviour gbMSM population size in 2020 was estimated at 669,613 people, equivalent to 4.3% of the Canadian male population aged 15 years and older. The estimate of Behaviour-only gbMSM was 412,186, representing 2.6% of the Canadian male population aged 15 years and older. Conclusion: Using data from multiple sources, a model applied to estimate the population size of gbMSM, accounting for populations previously not included in prior estimates, has been described.

13.
Eukaryot Cell ; 10(9): 1148-55, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21724934

RESUMO

Small RNA molecules of about 20 to 30 nucleotides function in gene regulation and genomic defense via conserved eukaryotic RNA interference (RNAi)-related pathways. The RNAi machinery consists of three core components: Dicer, Argonaute, and RNA-dependent RNA polymerase. In fungi, the RNAi-related pathways have three major functions: genomic defense, heterochromatin formation, and gene regulation. Studies of Schizosaccharomyces pombe and Neurospora, and other fungi have uncovered surprisingly diverse small RNA biogenesis pathways, suggesting that fungi utilize RNAi-related pathways in various cellular processes to adapt to different environmental conditions. These studies also provided important insights into how RNAi functions in eukaryotic systems in general. In this review, we will discuss our current understanding of the fungal RNAi-related pathways and their functions, with a focus on filamentous fungi. We will also discuss how RNAi can be used as a tool in fungal research.


Assuntos
Fungos/genética , MicroRNAs/genética , Interferência de RNA , RNA Fúngico/genética , RNA Interferente Pequeno/genética , Fungos/metabolismo , Regulação da Expressão Gênica , Inativação Gênica , Genoma , MicroRNAs/biossíntese , Modelos Genéticos , Neurospora crassa/genética , Neurospora crassa/metabolismo , RNA Fúngico/biossíntese , RNA Interferente Pequeno/biossíntese , RNA Polimerase Dependente de RNA/genética , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo
14.
Can Commun Dis Rep ; 48(11-12): 540-549, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-38222827

RESUMO

Background: Estimates of the number of hepatitis C virus (HCV) infections are important for monitoring efforts aimed at preventing disease transmission, especially following the introduction of a highly effective treatment. This report provides updated estimates of HCV incidence, prevalence, undiagnosed proportion and treatment in Canada. Methods: A combination of back calculation modelling and a modified version of the workbook method were used to estimate the incidence and prevalence of anti-HCV positive persons, the prevalence of chronic HCV infection and the undiagnosed proportion. The number of people treated for chronic HCV was estimated using administrative pharmaceutical data. Results: An estimated 9,470 new infections occurred in 2019, corresponding to an incidence rate of 25 per 100,000 population, a 7.7% decrease since 2015. The estimated prevalence of anti-HCV antibodies in the Canadian population was 1.03% (plausible range: 0.83%-1.38%), and the estimated prevalence of chronic HCV was 0.54% (plausible range: 0.40%-0.79%). The overall proportion of anti-HCV positive persons who were undiagnosed was estimated at 24% of all infections, with individuals born between 1945 and 1975 being the priority population the most likely to be undiagnosed. An estimated 74,500 people with chronic HCV have been treated since the introduction of direct-acting antivirals in 2014. Conclusion: Estimates of HCV incidence and prevalence are key metrics to guide interventions and resource allocation. While our estimates show that HCV incidence has decreased in Canada in recent years and treatment of chronic HCV has continued to increase, ongoing efforts are required to reduce the burden of HCV in Canada.

15.
Can Commun Dis Rep ; 47(56): 251-258, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34220349

RESUMO

INTRODUCTION: : Canada has endorsed the Joint United National Programme on HIV and AIDS global targets to end the acquired immunodeficiency syndrome (AIDS) epidemic, including reducing new human immunodeficiency virus (HIV) infections to zero, by 2030. Given the effectiveness of pre-exposure prophylaxis (PrEP) to prevent new infections, it is important to measure and report on PrEP utilization to help inform planning for HIV prevention programs and policies. METHODS: : Annual estimates of persons using PrEP in Canada were generated for 2014-2018 from IQVIA's geographical prescription monitor dataset. An algorithm was used to distinguish users of tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) for PrEP versus treatment or post-exposure prophylaxis. We provide the estimated number of people using PrEP in eight Canadian provinces by sex, age group, prescriber specialty and payment type. RESULTS: : The estimated number of PrEP users increased dramatically over the five-year study period, showing a 21-fold increase from 460 in 2014 to 9,657 in 2018. Estimated PrEP prevalence was 416 users per million persons across the eight provinces in 2018. Almost all PrEP users were male. Use increased in both sexes, but increase was greater for males (23-fold) than females (five-fold). Use increased across all provinces, although there were jurisdictional differences in the prevalence of use, age distribution and prescriber types. CONCLUSION: : The PrEP use in Canada increased from 2014 to 2018, demonstrating increased awareness and uptake of its use for preventing HIV transmission. However, there was uneven uptake by age, sex and geography. Since new HIV infections continue to occur in Canada, it will be important to further refine the use of PrEP, as populations at higher risk of HIV infection need to be offered PrEP as part of comprehensive sexual healthcare.

16.
J Int Med Res ; 49(12): 3000605211062789, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34898308

RESUMO

OBJECTIVE: To explore the effects of sedation and analgesia with dexmedetomidine and other drugs on the stress response in patients with cerebral hemorrhage after craniotomy hematoma removal and bone flap decompression and insertion of an indwelling endotracheal catheter. METHODS: A total of 180 patients with cerebral hemorrhage with consciousness disturbance who underwent emergency surgery were included in this study. They were divided into six groups treated with propofol, dexmedetomidine, lidocaine, sufentanil, dezocine, and remifentanil, respectively. Intravenous medication was given after recovery of spontaneous respiration, and stress responses were compared among the group. RESULTS: Serum concentrations of norepinephrine, epinephrine, and cortisol and systolic blood pressure were significantly correlated with drug treatment. Serum norepinephrine concentrations differed significantly among the groups, except between the sufentanil and propofol groups. There were significant differences in serum epinephrine concentrations among all groups, and significant differences in serum cortisol concentrations among all groups, except the propofol, dexmedetomidine, and lidocaine groups. CONCLUSION: Dexmedetomidine can reduce the stress response in patients with intracerebral hemorrhage undergoing emergency craniotomy and bone flap decompression, and can reduce adverse events from an indwelling endotracheal catheter 3 hours post-operation.


Assuntos
Dexmedetomidina , Propofol , Analgésicos , Craniotomia , Descompressão , Dexmedetomidina/uso terapêutico , Humanos , Hipnóticos e Sedativos/uso terapêutico
17.
Am J Obstet Gynecol ; 203(4): 334.e1-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20579958

RESUMO

OBJECTIVE: Maternal smoking and preeclampsia independently increase the risk of adverse pregnancy outcomes; however, smoking decreases the risk of preeclampsia. We sought to estimate the risk of adverse pregnancy outcomes among preeclamptic women who smoke and hypothesized that this risk would be increased, compared with nonpreeclamptic women who smoke or preeclamptic women who do not smoke. STUDY DESIGN: With the use of the Niday Perinatal Database and multiple logistic regressions, we estimated the risk of adverse pregnancy outcomes in nonpreeclamptic women who smoke, preeclamptic women who do not smoke, and preeclamptic women who smoke in relation to nonpreeclamptic women who do not smoke. RESULTS: The incidence of adverse pregnancy outcomes was more than twice as high among preeclamptic women who smoke as among nonpreeclamptic women who do not smoke. The following data were observed: small-for-gestational-age infant (odds ratio [OR], 3.40; 95% CI, 2.27-4.89), preterm birth (OR, 5.77; 95% CI, 4.50-7.35), very preterm birth (OR, 5.44; 95% CI, 3.51-8.11), abruption (OR, 6.16; 95% CI, 3.05-11.01), Apgar <4 at 5 minutes (OR, 3.11; 95% CI, 1.48-5.72), and stillbirth (OR, 3.39; 95% CI, 1.33-6.99). CONCLUSION: Smoking decreases the risk of preeclampsia, but smokers with preeclampsia have an increased risk for adverse pregnancy outcomes.


Assuntos
Pré-Eclâmpsia/epidemiologia , Resultado da Gravidez , Fumar/efeitos adversos , Descolamento Prematuro da Placenta/epidemiologia , Adulto , Índice de Apgar , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Ontário/epidemiologia , Gravidez , Nascimento Prematuro/epidemiologia , Risco , Fumar/epidemiologia , Natimorto/epidemiologia
18.
J Obstet Gynaecol Can ; 32(11): 1042-1048, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21176315

RESUMO

OBJECTIVE: to assess the association between neighbourhood family income and adverse birth outcomes. METHODS: we conducted a retrospective cohort study of 334 231 singleton births during 2004 and 2006 based on the Niday Perinatal Database from Ontario. Median neighbourhood family incomes from the 2001 Canadian census were linked with the Niday Perinatal Database by dissemination areas. Generalized estimating equations were applied to estimate the odds ratios of adverse birth outcomes associated with lower neighbourhood income, with adjustment for maternal confounding variables at the individual level. RESULTS: compared with the highest neighbourhood income quintile, mothers from the lowest quintile were at increased risk of having small for gestational age neonates (OR 1.51; 95% CI 1.46 to 1.57), low birth weight (OR 1.43; 95% CI 1.36 to 1.50), preterm birth (OR 1.17; 95% CI 1.12 to 1.23), low Apgar score (< 7) at five minutes (OR 1.32; 95% CI 1.21 to 1.44), and stillbirth (OR 1.39; 95% CI 1.19 to 1.62). The risks of women from the lowest income quintiles delivering a macrosomic baby (OR 0.81; 95% CI 0.79 to 0.84) or a large for gestational age baby (OR 0.82; 95% CI 0.80 to 0.85) were significantly decreased. No difference in risk of congenital anomaly was found among different income quintiles. CONCLUSION: a lower level of neighbourhood income is associated with increased risks of small for gestational age babies, low birth weight, preterm birth, low Apgar score at five minutes, and stillbirth.


Assuntos
Renda , Resultado da Gravidez/epidemiologia , Características de Residência/estatística & dados numéricos , Índice de Apgar , Estudos de Coortes , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez , Estudos Retrospectivos , Fatores de Risco , Natimorto/epidemiologia
19.
Can J Public Health ; 101(6): 486-90, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21370786

RESUMO

OBJECTIVE: To estimate the number of prevalent and incident HIV infections in Canada in 2008. METHODS: We applied multiple methods to estimate national HIV prevalence and incidence in Canada, including the workbook method, two statistical modelling methods, and an iterative spreadsheet model. RESULTS: The estimated number of people living with diagnosed or undiagnosed HIV infection (including AIDS) continues to rise, from an estimated 57,000 in 2005 to 65,000 in 2008. Nearly half (48%) of these HIV-infected persons were men who have sex with men (MSM) and 22% were women. An estimated 16,900 persons with prevalent infection (26% of total prevalent infections) were unaware of their HIV-infected status and this proportion varied from an estimated 19% of HIV-infected MSM, to 25% of HIV-infected people who inject drugs, and 35% of HIV-infected heterosexuals. An estimated 3,300 new infections occurred in Canada in 2008, which was about the same as the estimate of 3200 in 2005. Of those new infections, 26% were among women and 12.5% were of Aboriginal descent; in terms of exposure category, MSM continued to comprise the greatest proportion of new infections (44%) and heterosexuals who originated in countries where HIV is endemic comprised 16%. CONCLUSION: HIV incidence in Canada is not decreasing. Aboriginal people and people from HIV-endemic countries continue to be over-represented in Canada's HIV epidemic. People unaware of their HIV infection are a priority for being tested and diagnosed to enable them to take advantage of care services and receive counselling to prevent further spread of HIV.


Assuntos
Infecções por HIV/epidemiologia , Canadá/epidemiologia , Feminino , Humanos , Incidência , Masculino , Prevalência , Estatística como Assunto
20.
Sci Rep ; 10(1): 9652, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541846

RESUMO

rgsCaM has been reported as a calmodulin-like (CML) factor induced by viral infection in Nicotiana. There are three CMLs that belong to the rgsCaM family in Arabidopsis thaliana. In this study, we found a total of 5 NbrgsCaM coding sequences in N. benthamiana genome. We analyzed transcription patterns of NbrgsCaMs in transgenic plants expressing a ß-glucuronidase (GUS) under the promoter of NbrgsCaMs by histochemistry staining and RT-qPCR. Similar to their Arabidopsis homologs, most NbrgsCaMs have an overlapping but distinct expression pattern in response to developmental and environmental changes. Specifically, the NbrgsCaM4 promoter exhibited robust activity and showed distinct regulatory response to viral infection, developmental stages and other abiotic stimuli. Overall, these findings provide clues for further understanding of the NbrgsCaM family genes in regulating plant growth and development under biotic stress and environmental stimulation.


Assuntos
Calmodulina/genética , Calmodulina/metabolismo , Nicotiana/fisiologia , Análise de Sequência de DNA/métodos , Resistência à Doença , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Glucuronidase/genética , Glucuronidase/metabolismo , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Regiões Promotoras Genéticas , Estresse Fisiológico , Nicotiana/genética , Nicotiana/virologia
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