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1.
Parasit Vectors ; 16(1): 388, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891582

RESUMO

BACKGROUND: Chromosomal inversion polymorphisms have been associated with adaptive behavioral, physiological, morphological and life history traits in the two main Afrotropical malaria vectors, Anopheles coluzzii and Anopheles gambiae. The understanding of the adaptive value of chromosomal inversion systems is constrained by the feasibility of cytological karyotyping. In recent years in silico and molecular approaches have been developed for the genotyping of most widespread inversions (2La, 2Rb and 2Rc). The 2Ru inversion, spanning roughly 8% of chromosome 2R, is commonly polymorphic in West African populations of An. coluzzii and An. gambiae and shows clear increases in frequency with increasing rainfall seasonally and geographically. The aim of this work was to overcome the constraints of currently available cytological and high-throughput molecular assays by developing a simple PCR assay for genotyping the 2Ru inversion in individual specimens of both mosquito species. METHODS: We designed tetra-primer amplification refractory mutation system (ARMS)-PCR assays based on five tag single-nucleotide polymorphisms (SNPs) previously shown to be strongly correlated with 2Ru inversion orientation. The most promising assay was validated against laboratory and field samples of An. coluzzii and An. gambiae karyotyped either cytogenetically or molecularly using a genotyping-in-thousands by sequencing (GT-seq) high-throughput approach that employs targeted sequencing of multiplexed PCR amplicons. RESULTS: A successful assay was designed based on the tag SNP at position 2R, 31710303, which is highly predictive of the 2Ru genotype. The assay, which requires only one PCR, and no additional post-PCR processing other than electrophoresis, produced a clear banding pattern for 98.5% of the 454 specimens tested, which is a 96.7% agreement with established karyotyping methods. Sequences were obtained for nine of the An. coluzzii specimens manifesting 2Ru genotype discrepancies with GT-seq. Possible sources of these discordances are discussed. CONCLUSIONS: The tetra-primer ARMS-PCR assay represents an accurate, streamlined and cost-effective method for the molecular karyotyping of the 2Ru inversion in An. coluzzii and An. gambiae. Together with approaches already available for the other common polymorphic inversions, 2La, 2Rb and 2Rc, this assay will allow investigations of the adaptive value of the complex set of inversion systems observed in the two major malaria vectors in the Afrotropical region.


Assuntos
Anopheles , Malária , Animais , Anopheles/genética , Inversão Cromossômica/genética , Mosquitos Vetores/genética , Cariotipagem , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Nucleotídeo Único
2.
Mol Biol Evol ; 40(4)2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36971242

RESUMO

Aedes aegypti vectors the pathogens that cause dengue, yellow fever, Zika virus, and chikungunya and is a serious threat to public health in tropical regions. Decades of work has illuminated many aspects of Ae. aegypti's biology and global population structure and has identified insecticide resistance genes; however, the size and repetitive nature of the Ae. aegypti genome have limited our ability to detect positive selection in this mosquito. Combining new whole genome sequences from Colombia with publicly available data from Africa and the Americas, we identify multiple strong candidate selective sweeps in Ae. aegypti, many of which overlap genes linked to or implicated in insecticide resistance. We examine the voltage-gated sodium channel gene in three American cohorts and find evidence for successive selective sweeps in Colombia. The most recent sweep encompasses an intermediate-frequency haplotype containing four candidate insecticide resistance mutations that are in near-perfect linkage disequilibrium with one another in the Colombian sample. We hypothesize that this haplotype may continue to rapidly increase in frequency and perhaps spread geographically in the coming years. These results extend our knowledge of how insecticide resistance has evolved in this species and add to a growing body of evidence suggesting that Ae. aegypti has an extensive genomic capacity to rapidly adapt to insecticide-based vector control.


Assuntos
Aedes , Genoma de Inseto , Resistência a Inseticidas , Inseticidas , Animais , Aedes/genética , Dengue , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mosquitos Vetores/genética , Mutação , Zika virus , Infecção por Zika virus , Genoma de Inseto/efeitos dos fármacos , Genoma de Inseto/genética
3.
Radiography (Lond) ; 27 Suppl 1: S34-S38, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34417105

RESUMO

OBJECTIVE: To explore relevant literature and policy around the role of the radiographer working within osteoporosis services. Discussion will examine the value of radiographers in these services, as well as current limitations and future opportunities for advancing practice in these domains. KEY FINDINGS: Osteoporosis and fracture prevention are a public health issue that must be addressed to improve patient outcomes following fractures. DXA radiographers currently fulfill an important role in the diagnosis of osteoporosis and collaborative working between radiology and osteoporosis services is to be encouraged. Radiographers are able to extend their role into advanced practice within osteoporosis services such as fracture liaison and rheumatology, they have expert knowledge and experience to bring to these roles and post graduate education can further increase radiographer's expertise in this field. The inability of diagnostic radiographers to become independent prescribers is a current limitation for radiographers working within osteoporosis services. CONCLUSION: The role of the radiographer working within DXA and osteoporosis services is evolving and is an exciting area of advanced practice. Promoting this specialty within radiography may help to improve job satisfaction as well as recruitment and retention rates. As radiographers scope of practice in osteoporosis changes and evolves, it is hoped that current legislation may change to allow independent prescribing for diagnostic radiographers, which can in turn streamline patient pathways and reduce the burden on primary and secondary care.


Assuntos
Fraturas Ósseas , Osteoporose , Radiologia , Pessoal Técnico de Saúde , Humanos , Osteoporose/diagnóstico por imagem , Radiografia
4.
Insects ; 11(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33065978

RESUMO

Polymorphic chromosomal inversions have been implicated in local adaptation. In anopheline mosquitoes, inversions also contribute to epidemiologically relevant phenotypes such as resting behavior. Progress in understanding these phenotypes and their mechanistic basis has been hindered because the only available method for inversion genotyping relies on traditional cytogenetic karyotyping, a rate-limiting and technically difficult approach that is possible only for the fraction of the adult female population at the correct gonotrophic stage. Here, we focus on an understudied malaria vector of major importance in sub-Saharan Africa, Anopheles funestus. We ascertain and validate tag single nucleotide polymorphisms (SNPs) using high throughput molecular assays that allow rapid inversion genotyping of the three most common An. funestus inversions at scale, overcoming the cytogenetic karyotyping barrier. These same inversions are the only available markers for distinguishing two An. funestus ecotypes that differ in indoor resting behavior, Folonzo and Kiribina. Our new inversion genotyping tools will facilitate studies of ecotypic differentiation in An. funestus and provide a means to improve our understanding of the roles of Folonzo and Kiribina in malaria transmission.

5.
G3 (Bethesda) ; 10(9): 3299-3307, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32680855

RESUMO

Chromosomal inversion polymorphisms have special importance in the Anopheles gambiae complex of malaria vector mosquitoes, due to their role in local adaptation and range expansion. The study of inversions in natural populations is reliant on polytene chromosome analysis by expert cytogeneticists, a process that is limited by the rarity of trained specialists, low throughput, and restrictive sampling requirements. To overcome this barrier, we ascertained tag single nucleotide polymorphisms (SNPs) that are highly correlated with inversion status (inverted or standard orientation). We compared the performance of the tag SNPs using two alternative high throughput molecular genotyping approaches vs. traditional cytogenetic karyotyping of the same 960 individual An. gambiae and An. coluzzii mosquitoes sampled from Burkina Faso, West Africa. We show that both molecular approaches yield comparable results, and that either one performs as well or better than cytogenetics in terms of genotyping accuracy. Given the ability of molecular genotyping approaches to be conducted at scale and at relatively low cost without restriction on mosquito sex or developmental stage, molecular genotyping via tag SNPs has the potential to revitalize research into the role of chromosomal inversions in the behavior and ongoing adaptation of An. gambiae and An. coluzzii to environmental heterogeneities.


Assuntos
Anopheles , Malária , África Ocidental , Animais , Anopheles/genética , Inversão Cromossômica , Genótipo , Mosquitos Vetores
6.
G3 (Bethesda) ; 9(10): 3249-3262, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391198

RESUMO

Chromosomal inversion polymorphisms play an important role in adaptation to environmental heterogeneities. For mosquito species in the Anopheles gambiae complex that are significant vectors of human malaria, paracentric inversion polymorphisms are abundant and are associated with ecologically and epidemiologically important phenotypes. Improved understanding of these traits relies on determining mosquito karyotype, which currently depends upon laborious cytogenetic methods whose application is limited both by the requirement for specialized expertise and for properly preserved adult females at specific gonotrophic stages. To overcome this limitation, we developed sets of tag single nucleotide polymorphisms (SNPs) inside inversions whose biallelic genotype is strongly correlated with inversion genotype. We leveraged 1,347 fully sequenced An. gambiae and Anopheles coluzzii genomes in the Ag1000G database of natural variation. Beginning with principal components analysis (PCA) of population samples, applied to windows of the genome containing individual chromosomal rearrangements, we classified samples into three inversion genotypes, distinguishing homozygous inverted and homozygous uninverted groups by inclusion of the small subset of specimens in Ag1000G that are associated with cytogenetic metadata. We then assessed the correlation between candidate tag SNP genotypes and PCA-based inversion genotypes in our training sets, selecting those candidates with >80% agreement. Our initial tests both in held-back validation samples from Ag1000G and in data independent of Ag1000G suggest that when used for in silico inversion genotyping of sequenced mosquitoes, these tags perform better than traditional cytogenetics, even for specimens where only a small subset of the tag SNPs can be successfully ascertained.


Assuntos
Anopheles/classificação , Anopheles/genética , Cromossomos de Insetos , Cariotipagem , Polimorfismo Genético , Animais , Anopheles/parasitologia , Inversão Cromossômica , Evolução Molecular , Variação Genética , Genótipo , Humanos , Malária/transmissão , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Mosquitos Vetores/parasitologia , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes
7.
Int J Mol Sci ; 20(16)2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416146

RESUMO

Periodontal disease is characterised by a dense inflammatory infiltrate in the connective tissue. When the resolution is not achieved, the activation of T and B cells is crucial in controlling chronic inflammation through constitutive cytokine secretion and modulation of osteoclastogenesis. The present narrative review aims to overview the recent findings of the importance of T and B cell subsets, as well as their cytokine expression, in the pathogenesis of the periodontal disease. T regulatory (Treg), CD8+ T, and tissue-resident γδ T cells are important to the maintenance of gingival homeostasis. In inflamed gingiva, however, the secretion of IL-17 and secreted osteoclastogenic factor of activated T cells (SOFAT) by activated T cells is crucial to induce osteoclastogenesis via RANKL activation. Moreover, the capacity of mucosal-associated invariant T cells (MAIT cells) to produce cytokines, such as IFN-γ, TNF-α, and IL-17, might indicate a critical role of such cells in the disease pathogenesis. Regarding B cells, low levels of memory B cells in clinically healthy periodontium seem to be important to avoid bone loss due to the subclinical inflammation that occurs. On the other hand, they can exacerbate alveolar bone loss in a receptor activator of nuclear factor kappa-B ligand (RANKL)-dependent manner and affect the severity of periodontitis. In conclusion, several new functions have been discovered and added to the complex knowledge about T and B cells, such as possible new functions for Tregs, the role of SOFAT, and MAIT cells, as well as B cells activating RANKL. The activation of distinct T and B cell subtypes is decisive in defining whether the inflammatory lesion will stabilise as chronic gingivitis or will progress to a tissue destructive periodontitis.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Doenças Periodontais/etiologia , Doenças Periodontais/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Citocinas/metabolismo , Suscetibilidade a Doenças , Homeostase , Humanos , Ativação Linfocitária/imunologia , Osteogênese/genética , Osteogênese/imunologia , Doenças Periodontais/patologia
8.
Obes Rev ; 19(8): 1164-1172, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29701299

RESUMO

Despite a large and increasing evidence base on physical activity interventions, the high rates of physical inactivity and associated chronic diseases are continuing to increase globally. The purpose of this cumulative meta-analysis was to investigate the evolution of randomized controlled trial evidence of individual-level physical activity interventions to asses if new trials are contributing novel evidence to the field. Through a two-staged search process, primary studies examining the effects of interventions targeted at increasing physical activity within healthy adult populations were pooled and selected from eligible systematic reviews. Cumulative meta-analyses were performed on effect sizes immediately post-intervention (n = 62), and for long-term behaviour change (≥12-month post-baseline; n = 27). Sufficiency and stability of the evidence was assessed through application of pre-published indicators. Meta-analyses suggest overall positive intervention effects on physical activity. The evidence base for effectiveness immediately post-intervention reached levels of sufficiency and stability in 2007; and for long-term follow-up in 2011. In the time since, intervention effectiveness has not substantially changed, and further trials are unlikely to change the direction and magnitude of effect. Substantial evidence exists demonstrating that physical activity interventions can modify individual behaviour in controlled settings. Researchers are urged to shift focus towards investigating the optimization, implementation, sustainability and cost-effectiveness of interventions.


Assuntos
Exercício Físico , Comportamentos Relacionados com a Saúde , Humanos
9.
Adv Dent Res ; 29(1): 117-123, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29355416

RESUMO

A novel silver nanoparticle (AgNP) formulation was developed as a targeted application for the disinfection of carious dentine. Silver nitrate (AgNO3) was chemically reduced using sodium borohydrate (NaBH4) in the presence of sodium dodecyl sulfate (SDS) to form micelle aggregate structures containing monodisperse 6.7- to 9.2-nm stabilized AgNPs. AgNPs were characterized by measurement of electrical conductivity and dynamic light scattering, scanning electron microscopy, transmission electron microscopy, and inductively coupled plasma mass spectrometry. Antimicrobial activity of AgNPs was tested against planktonic cultures of representative gram-positive and gram-negative oral bacteria using well diffusion assays on tryptic soy broth media and monoculture biofilms grown with brain heart infusion ± sucrose anaerobically at 37°C on microtiter plates. Biofilm mass was measured by crystal violet assay. Effects were compared to silver diamine fluoride and chlorhexidine (negative controls) and 70% isopropanol (positive control) exposed cultures. In the presence of AgNPs, triplicate testing against Streptococcus gordonii DL1, C219, G102, and ATCC10558 strains; Streptococcus mutans UA159; Streptococcus mitis I18; and Enterococcus faecalis JH22 for planktonic bacteria, the minimum inhibitory concentrations were as low as 7.6 µg mL-1 and the minimum bacteriocidal concentrations as low as 19.2 µg mL-1 silver concentration. Microplate readings detecting crystal violet light absorption at 590 nm showed statistically significant differences between AgNP-exposed biofilms and where no antimicrobial agents were used. The presence of sucrose did not influence the sensitivity of any of the bacteria. By preventing in vitro biofilm formation for several Streptococcus spp. and E. faecalis, this AgNP formulation demonstrates potential for clinical application inhibiting biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Desinfetantes/farmacologia , Nitrato de Prata/farmacologia , Clorexidina/farmacologia , Cárie Dentária/microbiologia , Desinfetantes/química , Condutividade Elétrica , Enterococcus faecalis/efeitos dos fármacos , Fluoretos Tópicos/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica , Compostos de Amônio Quaternário/farmacologia , Compostos de Prata/farmacologia , Espectrofotometria Atômica , Streptococcus gordonii/efeitos dos fármacos , Streptococcus mitis/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos
10.
Cognition ; 168: 176-181, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28704734

RESUMO

A disruption in the sense of agency is the primary phenomenological feature of response to hypnotic suggestions but its cognitive basis remains elusive. Here we tested the proposal that distorted volition during response to suggestions arises from poor metacognition pertaining to the sources of one's control. Highly suggestible and control participants completed a motor task in which performance was reduced through surreptitious manipulations of cursor lag and stimuli speed. Highly suggestible participants did not differ from controls in performance or metacognition of performance, but their sense of agency was less sensitive to cursor lag manipulations, suggesting reduced awareness that their control was being manipulated. These results indicate that highly suggestible individuals have aberrant metacognition of agency and may be a valuable population for studying distortions in the sense of agency.


Assuntos
Metacognição , Sugestão , Volição , Adulto , Conscientização , Feminino , Humanos , Julgamento , Masculino , Autoeficácia , Adulto Jovem
11.
Mol Ecol ; 25(23): 5889-5906, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27759895

RESUMO

The molecular mechanisms and genetic architecture that facilitate adaptive radiation of lineages remain elusive. Polymorphic chromosomal inversions, due to their recombination-reducing effect, are proposed instruments of ecotypic differentiation. Here, we study an ecologically diversifying lineage of Anopheles gambiae, known as the Bamako chromosomal form based on its unique complement of three chromosomal inversions, to explore the impact of these inversions on ecotypic differentiation. We used pooled and individual genome sequencing of Bamako, typical (non-Bamako) An. gambiae and the sister species Anopheles coluzzii to investigate evolutionary relationships and genomewide patterns of nucleotide diversity and differentiation among lineages. Despite extensive shared polymorphism and limited differentiation from the other taxa, Bamako clusters apart from the other taxa, and forms a maximally supported clade in neighbour-joining trees based on whole-genome data (including inversions) or solely on collinear regions. Nevertheless, FST outlier analysis reveals that the majority of differentiated regions between Bamako and typical An. gambiae are located inside chromosomal inversions, consistent with their role in the ecological isolation of Bamako. Exceptionally differentiated genomic regions were enriched for genes implicated in nervous system development and signalling. Candidate genes associated with a selective sweep unique to Bamako contain substitutions not observed in sympatric samples of the other taxa, and several insecticide resistance gene alleles shared between Bamako and other taxa segregate at sharply different frequencies in these samples. Bamako represents a useful window into the initial stages of ecological and genomic differentiation from sympatric populations in this important group of malaria vectors.


Assuntos
Anopheles/genética , Inversão Cromossômica , Ecótipo , Genoma de Inseto , Alelos , Animais , Resistência a Inseticidas/genética , Mosquitos Vetores/genética , Polimorfismo Genético
12.
BMC Genomics ; 17: 187, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26944054

RESUMO

BACKGROUND: De novo reference assemblies that are affordable, practical to produce, and of sufficient quality for most downstream applications, remain an unattained goal for many taxa. Insects, which may yield too little DNA from individual specimens for long-read sequencing library construction and often have highly heterozygous genomes, can be particularly hard to assemble using inexpensive short-read sequencing data. The large number of insect species with medical or economic importance makes this a critical problem to address. RESULTS: Using the assembler DISCOVAR de novo, we assembled the genome of the African malaria mosquito Anopheles arabiensis using 250 bp reads from a single library. The resulting assembly had a contig N50 of 22,433 bp, and recovered the gene set nearly as well as the ALLPATHS-LG AaraD1 An. arabiensis assembly produced with reads from three sequencing libraries and much greater resources. DISCOVAR de novo appeared to perform better than ALLPATHS-LG in regions of low complexity. CONCLUSIONS: DISCOVAR de novo performed well assembling the genome of an insect of medical importance, using simpler sequencing input than previous anopheline assemblies. We have shown that this program is a viable tool for cost-effective assembly of a modestly-sized insect genome.


Assuntos
Anopheles/genética , Genoma de Inseto , Análise de Sequência de DNA/métodos , Alelos , Animais , Feminino , Biblioteca Gênica , Modelos Genéticos , Polimorfismo de Nucleotídeo Único
13.
Int Endod J ; 49(5): 462-70, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26011655

RESUMO

AIM: To investigate the effects of peptides derived from the sequence of collagen to inhibit penetration of human or bovine dentine by species of streptococci and enterococci. METHODOLOGY: Blocks of human or bovine root dentine were infected for 14 days with bacterial cultures, in the presence or absence of various collagen-like peptide sequences. Invasion of dentinal tubules was determined from microscopic images of histochemically stained dentine thin sections. Extent of invasion was expressed as tubule invasion index (TI), or tubule invasion factor (TIF) which, in addition to the density of invasion, took into account the depth of invasion. Data were analysed by two-way anova. RESULTS: Streptococcus gordonii, Streptococcus mutans and Enterococcus faecalis were associated with heavy invasion (TI >2.5, TIF >4) of human or bovine root dentinal tubules, with E. faecalis being the most penetrative. Incorporation of peptides Gly-Pro-Ala or Gly-Pro-Hyp into the in vitro model system significantly reduced (P < 0.05) dentine invasion by the three species of highly invasive organisms. Inhibition of bacterial invasion by the peptides was dose dependent, and the peptides did not inhibit bacterial growth in culture. CONCLUSION: Specific collagen-like peptide sequences inhibited the invasion of dentine in vitro by a range of oral bacteria. The peptides likely act as competitive inhibitors blocking bacterial collagen receptors and could potentially allow for target-specific control of dentine infections.


Assuntos
Colágeno/química , Dentina/microbiologia , Raiz Dentária/microbiologia , Animais , Bovinos , Enterococcus faecalis/patogenicidade , Humanos , Peptídeos/química , Streptococcus , Streptococcus mutans/patogenicidade
14.
Int Endod J ; 49(5): 471-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26016886

RESUMO

AIM: To fabricate a keratin hydrogel, characterize its functionality as a biomaterial and investigate the effects of keratin on growth and differentiation of odontoblast-like cells. METHODOLOGY: Keratins were extracted from sheep wool using a well-established technique. The extracted proteins were purified by dialysis, quantified by gel electrophoresis, mass spectrometry, amino acid analysis and inductively coupled mass spectrometry. The microstructure of the fabricated keratin hydrogels was studied by scanning electron microscopy, flow characteristics by rheometer, hydrolytic stability and cytocompatibility by Live/Dead(®) cell assay. Furthermore, the influence of keratin on odontoblast-like cells (MDPC-23) was assessed to confirm their bioactivity at different dilutions. Cell proliferation was studied using alamarBlue(®) assay and differentiation by alkaline phosphatase enzyme activity, alizarin red staining and calcium quantification, reverse transcription polymerase chain reaction (rt-PCR) and immunocytochemical staining for dentine matrix protein- 1 (DMP-1) expression. anova with Tukey's tests was performed for statistical comparison. RESULTS: The characterized hydrogel was injectable with a highly porous architecture that underwent slow degradation, and its cytocompatibility was statistically equivalent to collagen hydrogel (P > 0.05). Cell proliferation and differentiation were enhanced at the optimal keratin concentration of 0.1 mg mL(-1) . At this concentration, the influence of keratin on cell differentiation was demonstrated by marked elevation in alkaline phosphatase activity (P < 0.05), calcium deposition (P < 0.01), gene expression (P < 0.01) and positive immunostaining for DMP-1. CONCLUSION: The presence of keratin enhanced odontoblast cell behaviour. Keratin hydrogels may be a potential scaffold for pulp-dentine regen-eration.


Assuntos
Diferenciação Celular , Queratinas/fisiologia , Odontoblastos/fisiologia , Animais , Proliferação de Células , Polpa Dentária/citologia , Ovinos ,
15.
Food Funct ; 6(6): 1787-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25968481

RESUMO

Flow and mixing in the small intestine are multi-scale processes. Flows at the scale of the villi (finger-like structures of ≈500 µm length) are poorly understood. We developed a three-dimensional lattice-Boltzmann model to gain insight into the effects of villous movements and the rheology of digesta on flow, mixing and absorption of nutrients at the periphery of the intestinal lumen. Our model simulated the hydrodynamic consequences of villi movements that resulted from folding of the mucosa during longitudinal contractions. We found that cyclic approximation and separation of groups of villi generated laminar eddies at the edges of the group and augmented mass transfers in the radial direction between the inter-villous space and the intestinal lumen which improved the absorption of nutrients and mixing at the periphery of the lumen. This augmentation was greater with highly diffusible nutrients and with high levels of shear-thinning (pseudoplasticity) of the fluid. We compared our results with bulk flows simulations done by previous workers and concluded that villous movements during longitudinal contractions is a major radial mixing mechanism in the small intestine and increases mixing and absorption around the mucosa despite adverse rheology.


Assuntos
Digestão , Conteúdo Gastrointestinal/química , Absorção Intestinal , Mucosa Intestinal/fisiologia , Intestino Delgado/fisiologia , Modelos Biológicos , Peristaltismo , Algoritmos , Animais , Simulação por Computador , Difusão , Humanos , Hidrodinâmica , Imageamento Tridimensional , Mucosa Intestinal/anatomia & histologia , Intestino Delgado/anatomia & histologia , Cinética , Reologia/métodos , Viscosidade
16.
Science ; 347(6217): 1258524, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25431491

RESUMO

Introgressive hybridization is now recognized as a widespread phenomenon, but its role in evolution remains contested. Here, we use newly available reference genome assemblies to investigate phylogenetic relationships and introgression in a medically important group of Afrotropical mosquito sibling species. We have identified the correct species branching order to resolve a contentious phylogeny and show that lineages leading to the principal vectors of human malaria were among the first to split. Pervasive autosomal introgression between these malaria vectors means that only a small fraction of the genome, mainly on the X chromosome, has not crossed species boundaries. Our results suggest that traits enhancing vectorial capacity may be gained through interspecific gene flow, including between nonsister species.


Assuntos
Anopheles/classificação , Anopheles/genética , Evolução Molecular , Genoma de Inseto , Insetos Vetores/genética , Malária/transmissão , Animais , Anopheles/crescimento & desenvolvimento , Cromossomos de Insetos/genética , Genômica , Humanos , Filogenia , Polimorfismo Genético , Pupa/anatomia & histologia , Pupa/crescimento & desenvolvimento , Cromossomo X/genética
17.
Transpl Infect Dis ; 16(6): 941-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25491023

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection results in significant morbidity and mortality in lung transplant recipients. Ganciclovir (GCV) has dramatically reduced complications caused by CMV infections. Unfortunately, GCV resistance is identified in 5-10% of CMV-infected patients. Mismatched CMV status and ongoing replication due to immunosuppression are risk factors for drug resistance. Whether subtherapeutic GCV levels contribute to resistance remains unknown. METHODS: A retrospective review was conducted in all 51 patients who underwent lung transplantation between March 2007 and June 2008 at Loyola University Medical Center. GCV resistance and outcome data of CMV-infected patients were analyzed to identify variables that may contribute to suboptimal response to CMV infection. RESULTS: During the 16-month period, CMV infection was identified in 21 of 51 lung transplant recipients. Ten of 21 patients (47.6%) had CMV infection with early response to GCV, and 11 patients (52.4%) had CMV infection with suboptimal response to GCV. GCV levels were obtained in the 11 CMV-infected patients with suboptimal response. In 6 patients, GCV levels were therapeutic; all 6 had delayed response to GCV. In 5 patients, GCV levels were subtherapeutic; each had persistent suboptimal response to GCV. Genotyping documented GCV-resistant (GCV-R) CMV in all 5 patients. Cystic fibrosis as the diagnosis requiring lung transplantation was associated with GCV-R CMV infection (P = 0.01). CONCLUSION: In our lung transplant recipient cohort, GCV levels were subtherapeutic in all patients with persistent suboptimal response to GCV, each of whom had GCV-R CMV infection. In contrast, GCV levels were therapeutic in CMV-infected patients with delayed GCV response.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/efeitos dos fármacos , Farmacorresistência Viral , Ganciclovir/sangue , Transplante de Pulmão/efeitos adversos , Adulto , Idoso , Antivirais/sangue , Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Feminino , Ganciclovir/farmacologia , Ganciclovir/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Carga Viral , Adulto Jovem
18.
Physiol Res ; 63(3): 311-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24564596

RESUMO

Proteasomes appear to be involved in the pathophysiology of various acute and chronic lung diseases. Information on the human lung proteasome in health and disease, however, is sparse. Therefore, we studied whether end-stage pulmonary diseases are associated with alterations in lung 20S/26S proteasome content, activity and 20S subunit composition. Biopsies were obtained from donor lungs (n=7) and explanted lungs from patients undergoing lung transplantation because of end stage chronic obstructive pulmonary disease (COPD; n=7), idiopathic pulmonary fibrosis (IPF, n=7) and pulmonary sarcoidosis (n=5). 20S/26S proteasomes in lung extracts were quantified by ELISA, chymotrypsin-like proteasome peptidase activities measured and 20S proteasome beta subunits analyzed by Western blot. As compared with donor lungs, proteasome content was increased in IPF and sarcoidosis, but not in COPD. The relative distribution of free 20S and 26S proteasomes was similar; 20S proteasome was predominant in all extracts. Proteasome peptidase activities in donor and diseased lungs were indistinguishable. All extracts contained a mixed composition of inducible 20S beta immuno-subunits and their constitutive counterparts; a disease associated distribution could not be identified. A higher content of lung proteasomes in IPF and pulmonary sarcoidosis may contribute to the pathophysiology of human fibrotic lung diseases.


Assuntos
Pneumopatias/metabolismo , Pulmão/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Doadores de Tecidos
19.
N Z Dent J ; 110(4): 131-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25597193

RESUMO

OBJECTIVES: To describe the clinical oral health status, treatment needs and oral-health-related quality of life (OHRQoL) of older people admitted to older persons' wards at Dunedin Public Hospital due to a sudden worsening of their general health. Participants and methods: A systematic oral assessment was undertaken for a consecutive case series of 200 patients (59.5% female; mean age 82.6 years, sd 6.6) admitted to older person's wards at Dunedin Public Hospital. The Oral Health Impact Profile-20 (OHIP-20) was used to assess OHRQoL. RESULTS: One in three (36.0%) had been living independently at home prior to admission, and over half (55.0%) had been admitted for a medical reason which required assessment. Half (50.0%) of the participants were dentate (with an average of 16.8 teeth). There was an average of 1.9 decayed teeth present in the dentate group; 70.7% of individuals required restorations or extractions, and about 90% required only simple scaling of the teeth and prophylaxis. A reline or a replacement denture were required by three-quarters of those with dentures. Almost two-thirds of participants did not have a regular dentist, and fewer than one in three had made a dental visit in the previous year. One in six described their oral health as 'fair' or 'poor', and just under one-third reported dry mouth. Dentate participants, those without xerostomia, and those reporting better oral health had better OHRQoL, reflected in lower OHIP-20 scores. Affecting 37.1% of participants, functional limitation was the most commonly experienced of the OHIP-20 domains, followed by physical disability and physical pain (18.0% and 15.6% respectively). CONCLUSIONS: The oral health of medically compromised and functionally dependent but cognitively competent older people in this study is generally poor. If transfer to long-term care is indicated, early and proper preventive measures and appropriate dental contact should be advocated in order to reduce morbidity and improve quality of life for older people.


Assuntos
Avaliação Geriátrica/estatística & dados numéricos , Nível de Saúde , Avaliação das Necessidades/estatística & dados numéricos , Saúde Bucal/estatística & dados numéricos , Qualidade de Vida , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Índice CPO , Assistência Odontológica/estatística & dados numéricos , Profilaxia Dentária/estatística & dados numéricos , Restauração Dentária Permanente/estatística & dados numéricos , Raspagem Dentária/estatística & dados numéricos , Reembasamento de Dentadura/estatística & dados numéricos , Dentaduras/estatística & dados numéricos , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Humanos , Vida Independente/estatística & dados numéricos , Masculino , Nova Zelândia/epidemiologia , Medição da Dor/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Classe Social , Extração Dentária/estatística & dados numéricos , Xerostomia/epidemiologia
20.
Int Endod J ; 46(10): 971-81, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23521017

RESUMO

AIM: To investigate and compare the expression of the pathogen recognition receptors Toll-like receptor (TLR) 2 and TLR4, and the hard tissue resorption triad osteoprotegerin (OPG)-receptor activator of nuclear factor kappa-B ligand (RANKL)-receptor activator of nuclear factor kappa-B (RANK) in external inflammatory root resorption of endodontic origin (ER) and external cervical root resorption (ECR) by immunohistochemistry. METHODOLOGY: Formalin-fixed, paraffin-embedded archival specimens collected from teeth that were diagnosed clinically, radiographically and histopathologically with either ER (n = 9) or ECR (n = 9) were processed for immunohistochemistry to investigate and compare levels of TLR2, TLR4, OPG, RANKL, RANK, CD3, CD19 and CD83 expression. The histological features were evaluated via haematoxylin and eosin stain. Taylor's modification of the Brown and Brenn Gram stain was used for examining the presence and distribution of bacteria. All stained slides were digitally photographed and qualitatively analysed, and F test and unpaired Student's t-test were used for statistical analysis. RESULTS: Both ER and ECR showed similar immuno-histopathology characteristics of a fibrovascular connective tissue with varying degrees of inflammatory infiltrate consisting of T and B lymphocytes, dendritic cells, polymorphonuclear lymphocytes and plasma cells. Colonies of bacteria were identified in the majority of lesions, and this correlated with the cellular expression of TLR2 and TLR4 in all lesions. Similarly, all lesions showed a significantly higher (P < 0.05) level of cells expressing RANKL than OPG, indicating hard tissue resorption processes where active in the lesions. CONCLUSION: The immunohistopathology patterns of ECR samples were consistent with the bacteria-driven ER specimens, suggesting bacteria-induced inflammation may be involved in ECR.


Assuntos
Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Reabsorção da Raiz/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Colo do Dente/metabolismo , Humanos , Inflamação/metabolismo
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