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2.
Anaesthesia ; 77(10): 1077-1080, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35949181

Assuntos
Tórax , Humanos
3.
Clin Oncol (R Coll Radiol) ; 33(9): 550-559, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34315640

RESUMO

In 2020, the World Health Organization launched a major initiative to eliminate cervical cancer globally. The initiative is built around the three key pillars of human papillomavirus (HPV) vaccination, cervical screening and treatment, with associated intervention targets for the year 2030. The '90-70-90' targets specify that 90% of adolescent girls receive prophylactic HPV vaccination, 70% of adult women receive a minimum twice-in-a-lifetime cervical HPV test and 90% receive appropriate treatment for preinvasive or invasive disease. Modelling has shown that if these targets are met, the elimination of cervical cancer, defined as fewer than four cases per 100 000 women per annum, will be achieved within a century. Many high-income countries are well positioned to eliminate cervical cancer within the coming decades, but few have achieved '90-70-90' and many challenges must still be addressed to deliver these critical interventions effectively. This review considers the current status of cervical cancer control in relation to each of the three elimination pillars in high-income countries and discusses some of the developments that will assist countries in reaching these ambitious targets by 2030.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Adolescente , Adulto , Países Desenvolvidos , Detecção Precoce de Câncer , Feminino , Humanos , Programas de Rastreamento , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle
4.
Braz J Med Biol Res ; 54(7): e10687, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008757

RESUMO

Helicobacter pylori (H. pylori) induces an intense inflammatory response, mediated by proinflammatory cytokines, including interleukin (IL)-6 and its membrane receptor (IL-6R), which activates important signaling pathways in the development of gastric disease and cancer. We investigated the gene and protein expression of IL-6 and IL-6R and the influence of polymorphisms rs1800795, rs1800796, and rs1800797 on its gene expression together with H. pylori infection. Furthermore, an in-silico analysis was performed to support our results. Gastric biopsies were obtained from patients with gastric symptoms and patients with gastric cancer (GC) and were divided into groups (Control, Gastritis, and Cancer). H. pylori was detected by PCR. Real-time-qPCR was employed to determine gene expression, and western blot assay was used to analyze protein expression levels. PCR-RFLP was used to characterize IL-6 polymorphisms. Bioinformatics analyses were performed using the Gene Expression Omnibus (GEO) database and GEO2R to screen out differentially expressed genes (DEGs). H. pylori was detected in 43.3% of the samples. Statistically significant differences were found for IL-6 (P=0.0001) and IL-6R (P=0.0005) genes among the three groups, regardless of the presence of H. pylori. Among patients with H. pylori infection, the IL-6 and IL-6R gene and protein expressions were significantly increased, highlighting IL-6 gene overexpression in patients with GC. No statistically significant differences were found for the rs1800795, rs1800796, and rs1800797 polymorphisms compared to IL-6 gene expression. The results indicated that the IL-6 polymorphisms do not influence its expression, but IL-6 and IL-6R expression seems to be altered by the presence of H. pylori.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Interleucina-6/genética , Neoplasias Gástricas , Mucosa Gástrica , Gastrite/genética , Infecções por Helicobacter/genética , Humanos , Interleucina-8 , Neoplasias Gástricas/genética
5.
Neurobiol Dis ; 147: 105146, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33122075

RESUMO

Pathological accumulations of amyloid-beta (Aß) peptide are found in retina early in Alzheimer's disease, yet its effects on retinal neuronal structure remain unknown. To investigate this, we injected fibrillized Aß1-42 protein into the eye of adult C57BL/6 J mice and analyzed the retina, optic nerve (ON), and the superior colliculus (SC), the primary retinal target in mice. We found that retinal Aß exposure stimulated microglial activation and retinal ganglion cell (RGC) loss as early as 1-week post-injection. Pathology was not limited to the retina, but propagated into other areas of the central nervous system. Microgliosis spread throughout the retinal projection (retina, ON, and SC), with multiplex protein quantitation demonstrating an increase in endogenously produced Aß in the ON and SC corresponding to the injected retinas. Surprisingly, this pathology spread to the opposite side, with unilateral Aß eye injections driving increased Aß levels, neuroinflammation, and RGC death in the opposite, un-injected retinal projection. As Aß-mediated microglial activation has been shown to propagate Aß pathology, we also investigated the role of the Aß-binding microglial scavenger receptor CD36 in this pathology. Transgenic mice lacking the CD36 receptor were resistant to Aß-induced inflammation and RGC death up to 2 weeks following exposure. These results indicate that Aß pathology drives regional neuropathology in the retina and does not remain isolated to the affected eye, but spreads throughout the nervous system. Further, CD36 may serve as a promising target to prevent Aß-mediated inflammatory damage.


Assuntos
Precursor de Proteína beta-Amiloide/toxicidade , Gliose/patologia , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Animais , Antígenos CD36/metabolismo , Feminino , Humanos , Injeções Intravítreas , Masculino , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/patologia , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/patologia , Retina/efeitos dos fármacos , Retina/patologia , Colículos Superiores/efeitos dos fármacos , Colículos Superiores/patologia
6.
Braz. j. med. biol. res ; 54(7): e10687, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1249315

RESUMO

Helicobacter pylori (H. pylori) induces an intense inflammatory response, mediated by proinflammatory cytokines, including interleukin (IL)-6 and its membrane receptor (IL-6R), which activates important signaling pathways in the development of gastric disease and cancer. We investigated the gene and protein expression of IL-6 and IL-6R and the influence of polymorphisms rs1800795, rs1800796, and rs1800797 on its gene expression together with H. pylori infection. Furthermore, an in-silico analysis was performed to support our results. Gastric biopsies were obtained from patients with gastric symptoms and patients with gastric cancer (GC) and were divided into groups (Control, Gastritis, and Cancer). H. pylori was detected by PCR. Real-time-qPCR was employed to determine gene expression, and western blot assay was used to analyze protein expression levels. PCR-RFLP was used to characterize IL-6 polymorphisms. Bioinformatics analyses were performed using the Gene Expression Omnibus (GEO) database and GEO2R to screen out differentially expressed genes (DEGs). H. pylori was detected in 43.3% of the samples. Statistically significant differences were found for IL-6 (P=0.0001) and IL-6R (P=0.0005) genes among the three groups, regardless of the presence of H. pylori. Among patients with H. pylori infection, the IL-6 and IL-6R gene and protein expressions were significantly increased, highlighting IL-6 gene overexpression in patients with GC. No statistically significant differences were found for the rs1800795, rs1800796, and rs1800797 polymorphisms compared to IL-6 gene expression. The results indicated that the IL-6 polymorphisms do not influence its expression, but IL-6 and IL-6R expression seems to be altered by the presence of H. pylori.


Assuntos
Humanos , Neoplasias Gástricas/genética , Helicobacter pylori , Infecções por Helicobacter/genética , Interleucina-6/genética , Gastrite/genética , Interleucina-8 , Mucosa Gástrica
7.
J Small Anim Pract ; 61(6): 374-380, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32323333

RESUMO

OBJECTIVES: To investigate the effect of breed as a risk factor associated with humeral condylar fracture in skeletally immature dogs in the UK. MATERIALS AND METHODS: Retrospective study of dogs under 12 months of age that were presented with humeral condylar fracture to three specialist referral centres between 2015 and 2018. Data retrieved from medical records included breed, age, gender, neuter status, affected limb, fracture configuration and aetiology of the fracture. Breed population percentages were compared with those recorded by the UK Kennel Club. RESULTS: Of the 115 dogs with 118 fractures, French bulldogs (41%) and English springer spaniels (15%) were overrepresented: humeral condylar fractures were more commonly diagnosed in French bulldogs (odds ratio = 5.86) and English springer spaniels (odds ratio = 5.66) compared with mixed-breed dogs. Lateral condylar fractures occurred in 70% of cases, with medial condylar fractures and Y/T fractures accounting for 9% and 21%, respectively. Median age at the time of fracture was 4 months (range 2 to 10 months). CLINICAL SIGNIFICANCE: French bulldogs and English springer spaniels were identified as being at potentially increased risk of humeral condylar fracture in skeletally immature dogs.


Assuntos
Doenças do Cão , Fraturas do Úmero/veterinária , Animais , Cruzamento , Cães , Úmero , Estudos Retrospectivos , Fatores de Risco
8.
Health Phys ; 118(1): 53-59, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31764420

RESUMO

This study was motivated by the efforts to evaluate radiation risk for leukemia incidence in the Techa River cohort, where the main bone marrow dose contributors were Sr (bone-seeking beta emitters). Energy deposition in bone marrow targets was evaluated by simulating radiation particle transport using computational phantoms. The present paper describes the computer program Trabecula implementing an algorithm for parametric generation of computational phantoms, which serve as the basis for calculating bone marrow doses. Trabecula is a user-friendly tool that automatically converts analytical models into voxelized representations that are directly compatible as input to Monte Carlo N Particle code.


Assuntos
Medula Óssea/efeitos da radiação , Método de Monte Carlo , Imagens de Fantasmas , Radiometria/métodos , Software , Algoritmos , Humanos , Doses de Radiação
9.
BMC Evol Biol ; 19(1): 98, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064342

RESUMO

BACKGROUND: The Micronycterinae form a subfamily of leaf-nosed bats (Phyllostomidae) that contains the genera Lampronycteris Sanborn, 1949, and Micronycteris Gray, 1866 (stricto sensu), and is characterized by marked karyotypic variability and discrepancies in the phylogenetic relationships suggested by the molecular versus morphological data. In the present study, we investigated the chromosomal evolution of the Micronycterinae using classical cytogenetics and multidirectional chromosome painting with whole-chromosomes probes of Phyllostomus hastatus and Carollia brevicauda. Our goal was to perform comparative chromosome mapping between the genera of this subfamily and explore the potential for using chromosomal rearrangements as phylogenetic markers. RESULTS: The Micronycterinae exhibit great inter- and intraspecific karyotype diversity, with large blocks of telomere-like sequences inserted within or adjacent to constitutive heterochromatin regions. The phylogenetic results generated from our chromosomal data revealed that the Micronycterinae hold a basal position in the phylogenetic tree of the Phyllostomidae. Molecular cytogenetic data confirmed that there is a low degree of karyotype similarity between Lampronycteris and Micronycteris specimens analyzed, indicating an absence of synapomorphic associations in Micronycterinae. CONCLUSIONS: We herein confirm that karyotypic variability is present in subfamily Micronycterinae. We further report intraspecific variation and describe a new cytotype in M. megalotis. The cytogenetic data show that this group typically has large blocks of interstitial telomeric sequences that do not appear to be correlated with chromosomal rearrangement events. Phylogenetic analysis using chromosome data recovered the basal position for Micronycterinae, but did not demonstrate that it is a monophyletic lineage, due to the absence of common chromosomal synapomorphy between the genera. These findings may be related to an increase in the rate of chromosomal evolution during the time period that separates Lampronycteris from Micronycteris.


Assuntos
Quirópteros/classificação , Quirópteros/genética , Evolução Molecular , Cariótipo , Filogenia , Animais , Teorema de Bayes , Mapeamento Cromossômico , Coloração Cromossômica/métodos , Cromossomos de Mamíferos/genética
10.
Health Phys ; 117(4): 378-387, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30958804

RESUMO

Waterborne releases to the Techa River from the Mayak plutonium facility in Russia during 1949-1956 resulted in significant doses to persons living downstream. The dosimetry system Techa River Dosimetry System-2016D has been developed, which provides individual doses of external and internal exposure for the members of the Techa River cohort and other persons who were exposed to releases of radioactive material to the Southern Urals. The results of computation of individual doses absorbed in red bone marrow and extraskeletal tissues for the Techa River cohort members (29,647 persons) are presented, which are based on residence histories on the contaminated Techa River and the East Urals Radioactive Trace, which was formed in 1957 as a result of the Kyshtym Accident. Available Sr body-burden measurements and available information on individual household locations have been used for refinement of individual dose estimates. Techa River Dosimetry System-2016D-based dose estimates will be used for verification of risk of low-dose-rate effects of ionizing radiation in the Techa River cohort.


Assuntos
Exposição Ambiental/análise , Monitoramento de Radiação/métodos , Resíduos Radioativos/análise , Rios/química , Radioisótopos de Estrôncio/análise , Poluentes Radioativos da Água/análise , Carga Corporal (Radioterapia) , Estudos de Coortes , Feminino , Humanos , Masculino , Doses de Radiação , Radioisótopos de Estrôncio/farmacocinética , Distribuição Tecidual , Poluentes Radioativos da Água/farmacocinética
11.
Clin Exp Immunol ; 196(2): 226-236, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30693467

RESUMO

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder whose pathology involves multiple immune cell types, including B and T lymphocytes as well as myeloid cells. While it is clear that autoantibody-producing B cells, as well as CD4+ T cell help, are key contributors to disease, little is known regarding the role of innate lymphoid cells such as natural killer (NK) cells in the pathogenesis of SLE. We have characterized the phenotype of NK cells by multi-color flow cytometry in a large cohort of SLE patients. While the overall percentage of NK cells was similar or slightly decreased compared to healthy controls, a subset of patients displayed a high frequency of NK cells expressing the proliferation marker, Ki67, which was not found in healthy donors. Although expression of Ki67 on NK cells correlated with Ki67 on other immune cell subsets, the frequency of Ki67 on NK cells was considerably higher. Increased frequencies of Ki67+ NK cells correlated strongly with clinical severity and active nephritis and was also related to low NK cell numbers, but not overall leukopenia. Proteomic and functional data indicate that the cytokine interleukin-15 promotes the induction of Ki67 on NK cells. These results suggest a role for NK cells in regulating the immune-mediated pathology of SLE as well as reveal a possible target for therapeutic intervention.


Assuntos
Interleucina-15/metabolismo , Antígeno Ki-67/metabolismo , Células Matadoras Naturais/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite/metabolismo , Adolescente , Adulto , Idoso , Antígeno CD56/metabolismo , Células Cultivadas , Feminino , Humanos , Imunidade Inata/imunologia , Células Matadoras Naturais/imunologia , Leucopenia/imunologia , Leucopenia/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Nefrite/imunologia , Proteômica/métodos , Adulto Jovem
12.
Neuroscience ; 390: 104-118, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30149050

RESUMO

Retinal ganglion cell axons of the DBA/2J mouse model of glaucoma, a model characterized by extensive neuroinflammation, preserve synaptic contacts with their subcortical targets for a time after onset of anterograde axonal transport deficits, axon terminal hypertrophy, and cytoskeletal alterations. Though retrograde axonal transport is still evident in these axons, it is unknown if they retain their ability to transmit visual information to the brain. Using a combination of in vivo multiunit electrophysiology, neuronal tract tracing, multichannel immunofluorescence, and transmission electron microscopy, we report that eye-brain signaling deficits precede transport loss and axonal degeneration in the DBA/2J retinal projection. These deficits are accompanied by node of Ranvier pathology - consisting of increased node length and redistribution of the voltage-gated sodium channel Nav1.6 that parallel changes seen early in multiple sclerosis (MS) axonopathy. Further, with age, axon caliber and neurofilament density increase without corresponding changes in myelin thickness. In contrast to these findings in DBA/2J mice, node pathologies were not observed in the induced microbead occlusion model of glaucoma - a model that lacks pre-existing inflammation. After one week of systemic treatment with fingolimod, an immunosuppressant therapy for relapsing-remitting MS, DBA/2J mice showed a substantial reduction in node pathology and mild effects on axon morphology. These data suggest that neurophysiological deficits in the DBA/2J may be due to defects in intact axons and targeting node pathology may be a promising intervention for some types of glaucoma.


Assuntos
Glaucoma/fisiopatologia , Nós Neurofibrosos/fisiologia , Vias Visuais/fisiopatologia , Potenciais de Ação , Animais , Axônios/patologia , Citoesqueleto/patologia , Feminino , Glaucoma/metabolismo , Glaucoma/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Nós Neurofibrosos/ultraestrutura , Vias Visuais/metabolismo , Vias Visuais/ultraestrutura , Canais de Sódio Disparados por Voltagem/metabolismo
13.
J Environ Manage ; 224: 69-76, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30031920

RESUMO

Flood Risk Management (FRM) is often essential to reduce the risk of flooding to properties and infrastructure in urban landscapes, but typically degrades the habitats required by many aquatic animals for foraging, refuge and reproduction. This conflict between flood risk management and biodiversity is driven by conflicting directives, such as the EU Floods and Water Framework Directives, and has led to a requirement for synergistic solutions for FRM that integrate river restoration actions. Unfortunately, ecological monitoring and appraisal of combined FRM and river restoration works is inadequate. This paper uses a case study from the River Don in Northern England to evaluate the effects of the FRM and subsequent river restoration works on instream habitat and the associated fish assemblage over an 8-year period. Flood risk management created a homogeneous channel but did not negatively affect fish species composition or densities, specifically brown trout. Densities of adult brown trout were comparable pre and post-FRM, while densities of juvenile bullhead and brown trout increased dramatically post FRM. River restoration works created a heterogeneous channel but did not significantly improve species composition or brown trout density. Species composition post-river restoration works returned to that similar to pre-FRM over a short-term period, but with improved numbers of juvenile bullhead. Although habitat complexity increased after river restoration works, long-term changes in species composition and densities were marginal, probably because the river reset habitat complexity within the time framework of the study.


Assuntos
Inundações , Gestão de Riscos , Animais , Ecossistema , Inglaterra , Peixes , Rios
14.
Genome Announc ; 5(45)2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29122874

RESUMO

Here, we report the draft genome sequences of three laboratory variants of Bacillus anthracis Sterne and their double (Δlef Δcya) and triple (Δpag Δlef Δcya) toxin gene deletion derivatives.

15.
J Neurophysiol ; 117(6): 2269-2281, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28331006

RESUMO

To explore the brain mechanisms underlying multi-item working memory, we monitored the activity of neurons in the dorsolateral prefrontal cortex while macaque monkeys performed spatial and chromatic versions of a Sternberg working-memory task. Each trial required holding three sequentially presented samples in working memory so as to identify a subsequent probe matching one of them. The monkeys were able to recall all three samples at levels well above chance, exhibiting modest load and recency effects. Prefrontal neurons signaled the identity of each sample during the delay period immediately following its presentation. However, as each new sample was presented, the representation of antecedent samples became weak and shifted to an anomalous code. A linear classifier operating on the basis of population activity during the final delay period was able to perform at approximately the level of the monkeys on trials requiring recall of the third sample but showed a falloff in performance on trials requiring recall of the first or second sample much steeper than observed in the monkeys. We conclude that delay-period activity in the prefrontal cortex robustly represented only the most recent item. The monkeys apparently based performance of this classic working-memory task on some storage mechanism in addition to the prefrontal delay-period firing rate. Possibilities include delay-period activity in areas outside the prefrontal cortex and changes within the prefrontal cortex not manifest at the level of the firing rate.NEW & NOTEWORTHY It has long been thought that items held in working memory are encoded by delay-period activity in the dorsolateral prefrontal cortex. Here we describe evidence contrary to that view. In monkeys performing a serial multi-item working memory task, dorsolateral prefrontal neurons encode almost exclusively the identity of the sample presented most recently. Information about earlier samples must be encoded outside the prefrontal cortex or represented within the prefrontal cortex in a cryptic code.


Assuntos
Memória de Curto Prazo , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Macaca mulatta , Masculino , Córtex Pré-Frontal/citologia , Tempo de Reação
16.
Am J Transplant ; 17(2): 474-484, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27278097

RESUMO

The immunological role of exosomes in allograft rejection remains unknown. We sought to determine whether exosomes are induced during lung allograft rejection and to define the antigenic compositions of HLA, lung-associated self-antigens (SAgs) and microRNAs (miRNAs). Exosomes were isolated from sera and bronchoalveolar lavage fluid from 30 lung transplant recipients (LTxRs) who were stable or who had acute rejection (AR) or bronchiolitis obliterans syndrome (BOS). Exosomes were defined by flow cytometry for CD63 and western blotting for annexin V SAgs, collagen V (Col-V) and Kα1 tubulin were examined by electron microscopy; miRNAs were profiled by a miRNA array. Donor HLA and SAgs were detected on exosomes from LTxRs with AR and BOS but not from stable LTxRs. Exosomes expressing Col-V were isolated from sera from LTxRs 3 mo before AR and 6 mo before BOS diagnosis, suggesting that exosomes with SAgs may be a noninvasive rejection biomarker. Exosomes isolated from LTxRs with AR or BOS also contained immunoregulatory miRNAs. We concluded that exosomes expressing donor HLA, SAgs and immunoregulatory miRNAs are present in the circulation and local site after human lung transplantation and play an important role in the immune pathogenesis of acute allograft rejection and BOS.


Assuntos
Autoantígenos/imunologia , Bronquiolite Obliterante/etiologia , Exossomos/genética , Rejeição de Enxerto/etiologia , Transplante de Pulmão/efeitos adversos , MicroRNAs/genética , Doadores de Tecidos , Estudos de Casos e Controles , Exossomos/imunologia , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Fatores de Risco , Transplante Homólogo
17.
Chromosoma ; 126(2): 245-260, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27001473

RESUMO

Anoles are a clade of iguanian lizards that underwent an extensive radiation between 125 and 65 million years ago. Their karyotypes show wide variation in diploid number spanning from 26 (Anolis evermanni) to 44 (A. insolitus). This chromosomal variation involves their sex chromosomes, ranging from simple systems (XX/XY), with heterochromosomes represented by either micro- or macrochromosomes, to multiple systems (X1X1X2X2/X1X2Y). Here, for the first time, the homology relationships of sex chromosomes have been investigated in nine anole lizards at the whole chromosome level. Cross-species chromosome painting using sex chromosome paints from A. carolinensis, Ctenonotus pogus and Norops sagrei and gene mapping of X-linked genes demonstrated that the anole ancestral sex chromosome system constituted by microchromosomes is retained in all the species with the ancestral karyotype (2n = 36, 12 macro- and 24 microchromosomes). On the contrary, species with a derived karyotype, namely those belonging to genera Ctenonotus and Norops, show a series of rearrangements (fusions/fissions) involving autosomes/microchromosomes that led to the formation of their current sex chromosome systems. These results demonstrate that different autosomes were involved in translocations with sex chromosomes in closely related lineages of anole lizards and that several sequential microautosome/sex chromosome fusions lead to a remarkable increase in size of Norops sagrei sex chromosomes.


Assuntos
Evolução Molecular , Lagartos/genética , Cromossomos Sexuais , Animais , Bandeamento Cromossômico , Mapeamento Cromossômico , Coloração Cromossômica , Feminino , Genes Mitocondriais , Hibridização in Situ Fluorescente , Cariótipo , Cariotipagem , Masculino , Recombinação Genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-29311754

RESUMO

The mechanism that maintains a stable blood flow in the brain despite changes in cerebral perfusion pressure (CPP), and therefore guaranties a constant supply of oxygen and nutrients to the neurons, is known as cerebral autoregulation (CA). In a certain range of CPP, blood flow is mediated by a vasomotor adjustment in vascular resistance through dilation of blood vessels. CA is known to be impaired in diseases like traumatic brain injury, Parkinson's disease, stroke, hydrocephalus and others. If CA is impaired, blood flow and pressure changes are coupled and the oxygen supply might be unstable. Lassen's blood flow autoregulation curve describes this mechanism, where a plateau of stable blood flow in a specific range of CPP corresponds to intact autoregulation. Knowing the limits of this plateau and maintaining CPP within these limits can improve patient outcome. Since CPP is influenced by both intracranial pressure and arterial blood pressure, long term changes in either can lead to autoregulation impairment. Non-invasive methods for monitoring blood flow autoregulation are therefore needed. We propose to use Near infrared spectroscopy (NIRS) to fill this need. NIRS is an optical technique, which measures microvascular changes in cerebral hemoglobin concentration. We pe erformed experiments on non-human primates during exsanguination to demonstrate that the limits of blood flow autoregulation can be accessed with NIRS.

19.
Meat Sci ; 123: 21-28, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27591815

RESUMO

Meat quality parameters for 50 huacaya alpacas, representing three age groups (18, 24 and 36months) and two genders (females and castrated males) were studied. Prior to chilling, samples of m. longissimus thoracis et lumborum (LL) were taken to determine isocitrate dehydrogenase activity and glycogen concentration, and further meat quality samples were taken after 24h. Alpaca meat has low levels (<1%) of intramuscular fat in the LL, m. semimembranosus and m. biceps femoris, but the level in the LL increases with animal age, with levels of desirable polyunsaturated fatty acids (PUFA) ranging from 96.3 to 136.4mg/100g. Lipid oxidisation post retail display ranged from 1.27 to 1.96MDA/kg meat. Colour stability testing indicated alpaca meat was relatively stable during retail display with day of display having no significant effect on lightness (L*), or the 630nm/580nm ratio. These results may relate to the high proportion (76%) of glycolytic and type IIX muscle fibres in LL.


Assuntos
Tecido Adiposo/química , Fatores Etários , Camelídeos Americanos , Carne/análise , Fatores Sexuais , Animais , Cor , Gorduras na Dieta/análise , Ácidos Graxos/análise , Feminino , Análise de Alimentos , Qualidade dos Alimentos , Glicogênio/análise , Concentração de Íons de Hidrogênio , Isocitrato Desidrogenase/análise , Masculino , Músculo Esquelético/química , Substâncias Reativas com Ácido Tiobarbitúrico/análise
20.
Meat Sci ; 125: 53-60, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27888773

RESUMO

This study investigated the effects of feeding a mixed grain supplement and tenderstretching (TS) alpaca carcasses on meat quality. A total of 56 castrated 24month old alpacas were divided into two treatments (pasture-only, and pasture plus supplementation). Supplemented groups were fed a mixed grain ration in addition to ad lib pasture for 10weeks. Animals were slaughtered across two kill days (n=28). One half of each carcass was suspended by the pelvis (TS) prior to chilling, and the other half was Achilles tendon hung (AH). After 24h, muscles were removed and aged for 10 and 25d. TS significantly increased sarcomere length and reduced shear force and cooking loss in the m. semimembranosus. This trend was not observed in other muscles including the m. longissimus thoracis et lumborum (LL) and m. psoas major. Ageing period resulted in a marginal improvement in LL tenderness. There is clear evidence that TS improves tenderness in the hindquarter of alpacas.


Assuntos
Ração Animal/análise , Camelídeos Americanos , Dieta/veterinária , Qualidade dos Alimentos , Carne/análise , Matadouros , Tendão do Calcâneo/química , Animais , Cor , Comportamento do Consumidor , Culinária , Grão Comestível , Humanos , Concentração de Íons de Hidrogênio , Masculino , Músculo Esquelético/química , Temperatura
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