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1.
Front Oral Health ; 4: 1119086, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36908692

RESUMO

Purpose: We proposed that zinc (Zn) deposition in deciduous teeth would be a timed record of exposure to this essential micronutrient over very early life. We tested this hypothesis by gathering information on the maternal and child's diet during pregnancy and early infancy and measuring mineral deposition in the dentine at points during deciduous tooth development. Methods: We developed a short food frequency questionnaire (S-FFQ) to record consumption of food containing Zn during pregnancy and over the first year of life of the child in an Indonesian population. Zn, Sr and Ca were measured by laser ablation ICP-MS in a series of points across the developmental timeline in deciduous teeth extracted from 18 children undergoing the process as part of dental treatment whose mothers completed the SFFQ. Mothers and children were classified into either high Zn or low Zn groups according to calculated daily Zn intake. Results: The Zn/Sr ratio in dentine deposited over late pregnancy and 0-3 months post-partum was higher (p < 0.001, 2-way ANOVA; p < 0.05 by Holm-Sidak post hoc test) in the teeth of children of mothers classified as high Zn consumers (n = 10) than in children of mothers classified as low Zn consumers (n = 8). Conclusion: The S-FFQ was validated internally as adequately accurate to measure zinc intake retrospectively during pregnancy and post-partum (∼7 years prior) by virtue of the correlation with measurements of zinc in deciduous teeth. The ratio of Zn/Sr in deciduous teeth appears to be a biomarker of exposure to zinc nutrition during early development and offers promise for use as a record of prior exposure along a timeline for research studies and, potentially, to identify individuals at heightened risk of detrimental impacts of poor early life zinc nutrition on health in later life and to implement preventative interventions.

2.
Sci Rep ; 10(1): 1108, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980669

RESUMO

In the drill core of the Kola super-deep borehole (SG-3, 12,262 m depth) gold-bearing rocks of Archaean age have been located at depths of 9,500 to 11,000 m. In veins, between 9,052 and 10,744 m, within this gold zone, quartz contains fluid inclusions with gold nanoparticles. There are 4 types of fluid inclusions (1) gas inclusions of dense CO2, (2) liquid-vapor two-phase aqueous inclusions, (3) three-phase inclusions with NaCl daughter crystals, and (4) CO2-aqueous inclusions. In all inclusion types, there are extremely high concentrations of gold. The highest gold concentrations were found in the type 3 and 4 fluid inclusions with an average concentration of c. 750 ppm and may be as high as 6,000 ppm. The presence of gold as nanoparticles in the solutions of these fluid inclusions was determined by optical and spectroscopic methods. We suggest that these fluids could be a precursor of "orogenic gold fluids" which, at the gold concentrations determined, would reduce the requirements for large volumes of metamorphic fluids to form orogenic ore deposits. Further, as nanoparticles, gold could be transported in larger amounts than in true solution.

3.
BMJ Case Rep ; 20132013 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-23814006

RESUMO

Insertional tendinopathy of the adductor longus is a common and problematic condition in elite athletes and may lead to rupture. Previous literature has reported good outcomes in these patients when these ruptures are treated with both surgical and non-operative management. This paper will discuss the available literature on management of adductor tears and describe two case reports of deep infection following surgical repair of ruptures in soccer players and the effects this had on their profession. We conclude that, given the overall evidence of conservative management of adductor tears and possible complications associated with the surgery that these cases highlight, acute adductor tears in the majority should be treated conservatively.


Assuntos
Futebol Americano , Ruptura/diagnóstico , Tendinopatia/diagnóstico , Humanos , Masculino , Ruptura/cirurgia , Tendinopatia/cirurgia , Tomografia Computadorizada por Raios X
4.
J Psychiatr Ment Health Nurs ; 20(7): 595-600, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23013212

RESUMO

Mental health nurses frequently draw on self-disclosure practices within their working relationships. These 'confessional' acts can in turn be predicated on traditional assumptions of moral authority exercised by more senior colleagues. More broadly, attention has been drawn to the increasing significance of 'technologies of the self' inside neo-liberal regimes of governance. Through various forms of self-disclosure people are obliged 'to speak the truth about themselves'. By publically declaring themselves as 'fit for purpose' nurses are required to be reflexive, self-monitoring individuals, capable of constructing their own identities and biographies, and guided by expert knowledges. In this way, risk becomes a form of governance, as the individuals continually find themselves balancing risks and opportunities. Foucault's insights into the importance of 'care of the self' and 'surveillance of the self' to systems of social order and governance, such as mental health services, are significant in identifying nursing as a potential form of confessional practice. 'Reflective practice' and 'clinical supervision' are therefore 'technologies', functioning as 'modes of surveillance', and as 'confessional practices'. So 'clinical supervision' may be understood as part of a process of 'governance' that does not necessarily empower nurses, but can act to guide, correct and modify ways in which they conduct themselves.


Assuntos
Supervisão de Enfermagem/normas , Enfermagem Psiquiátrica/normas , Autorrevelação , Adulto , Humanos
5.
J Psychiatr Ment Health Nurs ; 20(6): 514-24, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22882808

RESUMO

There is a raft of policy guidelines indicating that mental health nurses should be increasing the social inclusion of mental health service users. Despite this there is no universally accepted definition of social inclusion and there is a dearth of empirical evidence on the successful outcome of increasing inclusion for mental health service users. Recognizing the lack of clarity surrounding the concept we have a produced a social inclusion framework to assist mental health professionals and service users to co-produce social inclusive outcomes. Although we agree that social inclusion can be a positive aspect of recovery, we question the extent to which mental health nurses and service users in co-production can overcome the social, economic and political structures that have created the social exclusion in the first place. An understanding and appreciation of the structure/agency conundrum is required if mental health nurses are to engage with service users in an attempt to co-produce socially inclusive outcomes.


Assuntos
Atitude Frente a Saúde , Transtornos Mentais/reabilitação , Serviços de Saúde Mental , Enfermagem Psiquiátrica/métodos , Distância Psicológica , Humanos , Apoio Social
6.
J Pediatr Rehabil Med ; 5(2): 75-88, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22699098

RESUMO

OBJECTIVE: A multi-site Randomized-Controlled Trial compared a home-based Supported Speed Treadmill Training Exercise Program (SSTTEP) with a strengthening exercise program in children with cerebral palsy (CP) on the following categories; Participation, quality of life (QOL), self-concept, goal attainment, and satisfaction. DESIGN: Twenty-six children with spastic cerebral palsy were assigned by site-based block randomization to the SSTTEP (n=14) or strengthening exercise (n=12) group. Both groups participated in a two week clinic-based induction period and continued the intervention at home for ten weeks. Data were collected at baseline, post-intervention (12 weeks), and follow-up (16 weeks). Assessments included the Canadian Occupational Performance Measure, Children's Assessment of Participation and Enjoyment Scale, Pediatric Quality of Life Cerebral Palsy Module, and Piers-Harris Children's Self-Concept Scale. Evaluators were blinded to group assignment at two sites. RESULTS: Satisfaction and performance on individual goals, participation, and parent-reported QOL improved in both groups with improvement maintained for four weeks post intervention. CONCLUSION: The hypothesis that the SSTTEP group would have better outcomes than the exercise group was not supported. However, both groups showed that children with CP can make gains in participation, individual goals, and satisfaction following a 12-week intensive exercise intervention, and these findings persisted for four weeks post intervention.


Assuntos
Paralisia Cerebral/reabilitação , Terapia por Exercício/métodos , Objetivos , Satisfação do Paciente , Qualidade de Vida , Autoimagem , Adolescente , Criança , Feminino , Seguimentos , Humanos , Masculino , Espasticidade Muscular/reabilitação , Inquéritos e Questionários , Resultado do Tratamento
7.
Opt Express ; 19(10): 9814-9, 2011 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-21643238

RESUMO

Titanium (Ti)-in-diffused lithium niobate waveguide mode filters fabricated using laser-induced forward transfer followed by thermal diffusion are presented. The mode control was achieved by adjusting the separation between adjacent Ti segments thus varying the average value of the refractive index along the length of the in-diffused channel waveguides. The fabrication details, loss measurements and near-field optical characterization of the mode filters are presented. Modeling results regarding the device performance are also discussed.

9.
Aust Vet J ; 84(9): 303-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16958624

RESUMO

OBJECTIVE: To determine the prevalence and geographical distribution of hydatidosis and investigate factors that might be expected to influence the prevalence of hydatids in cattle in Queensland north of the Tropic of Capricorn. To determine the effect of natural levels of infection on carcase weight and subsequent economic loss. PROCEDURE: An abattoir survey conducted in 1981 provided information on the distribution, prevalence and viability of hydatid cysts in cattle from all shires north of the Tropic of Capricorn in Queensland. Livers, lungs and spleens from 10,382 cattle were palpated at abattoirs in Cairns, Townsville and Rockhampton to detect hydatid cysts. Prevalence of infection in cattle in each shire was estimated from results of the abattoir study together with reports of infection in a further 22,185 cattle obtained from abattoir records. Linear modelling was used to define the effect of geographical origin, age, breed and sex on prevalence of infection. Differences in the weights of carcases between infected and non-infected cattle of the same age, sex, breed and property of origin were examined. The economic loss to the beef industry in the region surveyed was estimated. RESULTS: Cattle infected with hydatids originated almost entirely from regions to the east of the Great Dividing Range. The mean prevalence inside this zone was 28% compared with 3% in other areas. Viable protoscoleces were found in 0.7% of cysts. Geographical origin and age of the cattle were the most significant factors influencing prevalence. Infection with hydatids had no effect on carcase weight. Economic loss was limited to that associated with condemnations of organs at meat inspection, estimated to be 0.5 million dollars per annum in 1981 and 6 million dollars in 2004. The distribution of hydatids in Queensland north of the Tropic of Capricorn corresponded most closely with the distribution of small wallabies such as Macropus dorsalis (black-striped wallaby), M parryi (whiptail wallaby) and M rufogriseus (red-necked wallaby). CONCLUSIONS: It was concluded that cattle are not an important part of maintaining the life-cycle of E granulosus in Queensland north of the Tropic of Capricorn. Within the endemic zone, which is almost all to the east of the Great Dividing Range, the local pattern of bovine echinococcosis is most likely to be determined by the presence or absence of small species of wallaby such as M dorsalis, M parryi and M rufogriseus.


Assuntos
Doenças dos Bovinos/epidemiologia , Reservatórios de Doenças/veterinária , Equinococose/veterinária , Macropodidae/parasitologia , Matadouros , Fatores Etários , Animais , Bovinos , Doenças dos Bovinos/patologia , Doenças dos Bovinos/transmissão , Equinococose/epidemiologia , Equinococose/patologia , Equinococose/transmissão , Equinococose Hepática/epidemiologia , Equinococose Hepática/patologia , Equinococose Hepática/transmissão , Equinococose Hepática/veterinária , Equinococose Pulmonar/epidemiologia , Equinococose Pulmonar/patologia , Equinococose Pulmonar/transmissão , Equinococose Pulmonar/veterinária , Echinococcus granulosus , Feminino , Geografia , Masculino , Prevalência , Queensland/epidemiologia , Baço/parasitologia
10.
Aust Vet J ; 84(9): 308-11, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16958625

RESUMO

OBJECTIVE: To provide information on possible ecological determinants of infection with Echinococcus granulosus in a beef pastoral area of northern Queensland. PROCEDURE: An ecological study was carried out on the prevalence and viability of infection with Echinococcus granulosus in definitive and potential intermediate hosts, and their predator prey relationships. Seven adjacent extensive beef properties 100 km south of Townsville, that included areas of savannah, open woodland and dense closed scrub, were selected for the study. Infection with E granulosus in dingoes was determined at post mortem, and in domestic dogs by examining duodenal mucus after purging with arecoline hydrobromide. Cattle, wild pigs and macropods were examined at post mortem for viable hydatid cysts. The diet of dingoes was investigated by identifying the hair of prey species found in their stomach and colon, and that of domestic dogs by questioning their owners. RESULTS: Prevalence of hydatidosis in adult cattle ranged from 41% in animals from properties with large areas of dense closed scrub, to 3% on properties with little or no scrub. Hydatid cysts were found in 21.8% of black-striped wallabies (Macropus dorsalis), 9.4% of feral pigs, 1.5% of wallaroos (Macropus robustus), and 1.4% of eastern grey kangaroos (Macropus giganteus). No rufous rat kangaroos (Aepyprymnus rufescens) or swamp wallabies (Wallabia bicolor) were infected. Most cysts in macropods were viable, whereas in pigs about half were viable and in cattle only 0.7% contained viable protoscoleces. Infection with E granulosus was detected in 76% of dingoes, whereas no infection was detected in domestic dogs in the study area. CONCLUSIONS: It was concluded that the sylvatic cycle of E granulosus in the study area was maintained mainly through predation of black-striped wallabies by dingoes, and that the verges of dense scrub were the main nidus of infection.


Assuntos
Carnívoros/parasitologia , Doenças dos Bovinos/transmissão , Equinococose/veterinária , Meio Ambiente , Macropodidae/parasitologia , Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Equinococose/epidemiologia , Equinococose/parasitologia , Equinococose/transmissão , Echinococcus granulosus , Ecossistema , Feminino , Masculino , Comportamento Predatório , Prevalência , Queensland/epidemiologia
11.
Infect Immun ; 74(12): 6599-614, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17000720

RESUMO

Helicobacter pylori colonizes the gastric epithelium of at least 50% of the world's human population, playing a causative role in the development of chronic gastritis, peptic ulcers, and gastric adenocarcinoma. Current evidence indicates that H. pylori can invade epithelial cells in the gastric mucosa. However, relatively little is known about the biology of H. pylori invasion and survival in host cells. Here, we analyze both the nature of and the mechanisms responsible for the formation of H. pylori's intracellular niche. We show that in AGS cells infected with H. pylori, bacterium-containing vacuoles originate through the fusion of late endocytic organelles. This process is mediated by the VacA-dependent retention of the small GTPase Rab7. In addition, functional interactions between Rab7 and its downstream effector, Rab-interacting lysosomal protein (RILP), are necessary for the formation of the bacterial compartment since expression of mutant forms of RILP or Rab7 that fail to bind each other impaired the formation of this unique bacterial niche. Moreover, the VacA-mediated sequestration of active Rab7 disrupts the full maturation of vacuoles as assessed by the lack of both colocalization with cathepsin D and degradation of internalized cargo in the H. pylori-containing vacuole. Based on these findings, we propose that the VacA-dependent isolation of the H. pylori-containing vacuole from bactericidal components of the lysosomal pathway promotes bacterial survival and contributes to the persistence of infection.


Assuntos
Proteínas de Bactérias/fisiologia , Mucosa Gástrica/microbiologia , Helicobacter pylori/fisiologia , Fusão de Membrana , Vacúolos/microbiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Bactérias/genética , Catepsina D/análise , Catepsina D/metabolismo , Células Cultivadas , Cricetinae , Endocitose , Endossomos/microbiologia , Endossomos/fisiologia , Endossomos/ultraestrutura , Mucosa Gástrica/ultraestrutura , Humanos , Lisossomos/microbiologia , Lisossomos/fisiologia , Lisossomos/ultraestrutura , Mutação , Vacúolos/ultraestrutura , Proteínas rab de Ligação ao GTP/metabolismo , proteínas de unión al GTP Rab7
12.
Infect Immun ; 74(6): 3115-24, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16714539

RESUMO

Intracellular peptidoglycan (PG) recognition in human cells is mediated by the NACHT-LRR proteins Nod1 and Nod2. Elicitation of these proteins by PG motifs released from invasive bacteria triggers signaling events, resulting in the activation of the NF-kappaB pathway. In order to decipher the molecular components involved in Nod2 signal transduction, we set out to identify new interaction partners of Nod2 by using a yeast two-hybrid screen. Besides the known interaction partner RIP2, the screen identified the leucine-rich repeat (LRR)- and PDZ domain-containing family member Erbin as a binding partner of Nod2. Erbin showed a specific interaction with Nod2 in coimmunoprecipitation experiments with human HEK 293T cells. Immunofluorescence microscopy with a newly generated anti-Nod2 monoclonal antibody showed that Erbin and Nod2 partially colocalize in human cells. Subsequent analysis of the Erbin/Nod2 interaction revealed that the LRR of Erbin and the caspase activating and recruiting domains of Nod2 were necessary for this interaction. No significant interaction was observed with a Walker B box mutant of Nod2 or a Crohn's disease-associated frameshift mutant of Nod2, indicating that complex formation is dependent on the activity of the molecule. In addition, a change in the dynamics of the Erbin/Nod2 complex was observed during Shigella flexneri infection. Furthermore, ectopic expression of increasing amounts of Erbin or short hairpin RNA-mediated knockdown of Erbin showed a negative influence of Erbin on Nod2/muramyl-dipeptide-mediated NF-kappaB activation. These results implicate Erbin as a potential negative regulator of Nod2 and show that bacterial infection has an impact on Nod2/Erbin complex formation within cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Shigella flexneri/patogenicidade , Proteínas Adaptadoras de Transdução de Sinal/química , Células Cultivadas , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , NF-kappa B/metabolismo , Proteína Adaptadora de Sinalização NOD2 , Estrutura Terciária de Proteína
13.
Insect Biochem Mol Biol ; 33(5): 499-508, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12706629

RESUMO

We previously identified a novel Heliothis virescens 110 kDa aminopeptidase N (APN) that binds Bacillus thuringiensis (Bt) Cry1Ac and Cry1Fa delta-endotoxins, and cloned an internal region of the 110 kDa APN gene (Banks et al., 2001). Here we describe the RACE-PCR cloning and sequence of a cDNA encoding 110 kDa APN. The 110 kDa APN gene was transiently co-expressed with green fluorescent protein (GFP) in Drosophila S2 cells using the pIZT expression vector. Enrichment of total membranes purified from S2 cells transfected with the 110 kDa APN gene had 3.3 fold increased APN enzymatic activity relative to enriched total membranes purified from S2 cells transfected with vector alone. Whereas the majority of S2 cells transfected with the 110 kDa APN gene bound rhodamine-labeled Cry1Ac toxin, no S2 cells transfected with vector alone bound rhodamine-labeled Cry1Ac toxin. This indicates that toxin binding to whole cells is APN mediated. However, flow cytometry and microscopy indicated that 110 kDa APN transfected S2 cells exposed to Cry1Ac or Cry1Fa toxin did not experience an increase in membrane permeability, indicating that APN transfected cells were resistant to toxin. This suggests while the H. virescens 110 kDa APN functions as a Bt toxin binding protein, it does not mediate cytotoxicity when expressed in S2 cells.


Assuntos
Antígenos CD13/genética , Mariposas/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Antígenos CD13/química , Antígenos CD13/metabolismo , Linhagem Celular , Clonagem Molecular , Primers do DNA , Drosophila melanogaster , Dados de Sequência Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transfecção
14.
Environ Pollut ; 124(1): 151-71, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12683991

RESUMO

Long term, high level airborne emissions of pollutants from nickel industries on the Kola Peninsula (NW Russia) have resulted in widespread ecosystem injury up to almost complete vegetation eradication within nearest surroundings of the smelters. Although SO2 is the prevailing component of the emissions, it is only part of a much more complex chemical emission spectrum in the region. In addition to acidic gases, industry also emits potentially toxic elements (e.g. metals) which being less volatile than SO2, are deposited within the immediate region in significant concentrations. Additionally, it appears that sources of base cations (co-emission by smelters, sea aerosols, other industries) are adequate to prevent environmental acidification on the regional scale. Acidification of soils and waters appeared only as single cases in the immediate vicinity of the smelters and is not believed to be a major mechanism of environmental deterioration. Proposed critical concentrations (5 microg/m(3)) of SO2 for the northern ecosystems are exceeded over a large area and direct exposure to SO2 is believed to be the possible mechanism of vegetation damage.


Assuntos
Poluentes Atmosféricos , Ecossistema , Metalurgia , Níquel , Enxofre , Regiões Árticas , Bryopsida , Monitoramento Ambiental/métodos , Água Doce , Federação Russa , Dióxido de Enxofre/análise
15.
Physiol Meas ; 23(2): 437-48, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12051313

RESUMO

The design and characterization of instrumentation for application in evaluating the neural signal recording properties of probe-type microelectrodes, micromachined from silicon, are reported. Key aspects include the close matching of gain and frequency response between channels (better than 1%), flexibility in signal conditioning options, the ability to operate with a wide range of (microelectrode) recording site dimensions (4 microm x 4 micrm to 50 microm x 50 microm), and hence impedances, and the facility to monitor and store instrumentation settings on computer along with the recorded signals. Noise levels ranged from 3.7 microV rms for a 50 microm site, to 11.7 microV rms for a microm site, measured in saline. Close matching between channels was required to enable comparisons between different sites and different probes to be made with confidence; however, the instrumentation could be readily applied to less demanding applications.


Assuntos
Microeletrodos , Neurônios/fisiologia , Neurofisiologia/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Animais , Artefatos , Calibragem , Computadores , Gafanhotos , Software
16.
Sci Total Environ ; 277(1-3): 101-17, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11589391

RESUMO

A total of 1604 samples of crystalline bedrock groundwaters in Norway have been analysed for pH, major and minor elements. A subset of 476 samples were also analysed for a wide range of trace elements by ICP-MS. The pH of the samples ranges from 5.4 to 9.8, with a predominance of pH values between 8.0 and 8.2. The data-set is divided into five 20-percentile groups according to increasing pH. The concentrations of 60 elements are then displayed as box-plots for each pH group. A line through the five medians yields a visual demonstration of the relationship with, and sensitivity to, pH variations for concentrations of each element. Twelve characteristic trends are distinguishable, from which some of the main hydrogeochemical processes related to pH and groundwater evolution can be inferred.


Assuntos
Poluentes do Solo/análise , Poluentes da Água/análise , Abastecimento de Água , Monitoramento Ambiental , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Noruega , Oligoelementos/análise
17.
Insect Biochem Mol Biol ; 31(9): 909-18, 2001 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-11439250

RESUMO

We determined that Bacillus thuringiensis Cry1Ac and Cry1Fa delta-endotoxins recognize the same 110, 120 and 170 kDa aminopeptidase N (APN) molecules in brush border membrane vesicles (BBMV) from Heliothis virescens. The 110 kDa protein, not previously identified as an APN, contained a variant APN consensus sequence identical to that found in Helicoverpa punctigera APN 2. PCR amplification of H. virescens cDNA based on this sequence and a conserved APN motif yielded a 0.9 kb product that has 89% sequence homology with H. punctigera APN 2. Western blots revealed that the 110 kDa molecule was not recognized by soybean agglutinin, indicating the absence of GalNAc. A 125I labeled-Cry1Ac domain III mutant (509QNR(511)-AAA) that has an altered GalNAc binding pocket (Lee et al., Appl. Environ. Microbiol. 65 (1999) 4513) showed abolished binding to the 120 APN, reduced binding to the 170 kDa APN, and enhanced binding to the 110 kDa APN. Periodate treated H. virescens BBMV blots were also probed with 125I labeled-Cry1Ac and 509QNR(511)-AAA toxins. Both toxins still recognized the 110 kDa APN and a >210 kDa molecule which may be a cadherin-like protein. Additionally, 125I-(509)QNR(511)-AAA recognized periodate treated 170 kDa APN. Results indicate that the 110 kDa APN is distinct from other Cry1 toxin binding APNs and may be the first described Cry1Ac-binding APN that does not contain GalNAc.


Assuntos
Acetilgalactosamina/metabolismo , Aminopeptidases/metabolismo , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas , Endotoxinas/metabolismo , Proteínas de Insetos/metabolismo , Lectinas de Plantas , Proteínas de Soja , Sequência de Aminoácidos , Aminopeptidases/isolamento & purificação , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/imunologia , Biotina , Western Blotting , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Endotoxinas/imunologia , Proteínas Hemolisinas , Proteínas de Insetos/isolamento & purificação , Radioisótopos do Iodo , Lectinas/metabolismo , Ligantes , Dados de Sequência Molecular , Mariposas , Ácido Periódico , Reação em Cadeia da Polimerase/métodos , Dodecilsulfato de Sódio , Coloração e Rotulagem/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-11454240

RESUMO

BACKGROUND: Fracture healing slows with age. While 6-week-old rats regain normal bone biomechanics at 4 weeks after fracture, one-year-old rats require more than 26 weeks. The possible role of altered mRNA gene expression in this delayed union was studied. Closed mid-shaft femoral fractures were induced followed by euthanasia at 0 time (unfractured) or at 1, 2, 4 or 6 weeks after fracture in 6-week-old and 12-15-month-old Sprague-Dawley female rats. mRNA levels were measured for osteocalcin, type I collagen alpha1, type II collagen, bone morphogenetic protein (BMP)-2, BMP-4 and the type IA BMP receptor. RESULTS: For all of the genes studied, the mRNA levels increased in both age groups to a peak at one to two weeks after fracture. All gene expression levels decreased to very low or undetectable levels at four and six weeks after fracture for both age groups. At four weeks after fracture, the younger rats were healed radiographically, but not the older rats. CONCLUSIONS: (1) All genes studied were up-regulated by fracture in both age groups. Thus, the failure of the older rats to heal promptly was not due to the lack of expression of any of the studied genes. (2) The return of the mRNA gene expression to baseline values in the older rats prior to healing may contribute to their delayed union. (3) No genes were overly up-regulated in the older rats. The slower healing response of the older rats did not stimulate a negative-feedback increase in the mRNA expression of stimulatory cytokines.

19.
J Orthop Res ; 19(3): 428-35, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11398856

RESUMO

The impact of age and ovariectomy on the healing of femoral fractures was studied in three groups of female rats at 8, 32 and 50 weeks of age at fracture. In the two older groups, the rats had been subjected to ovariectomy or sham surgery at random at 26 weeks of age. At fracture, all rats received unilateral intramedullary pinning of one femur and a middiaphyseal fracture. Rigidity and breaking load of the femora were evaluated at varying times up to 24 weeks after fracture induction by three-point bending to failure. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. In the youngest group, 8-week-old female rats regained normal femoral rigidity and breaking load by 4 weeks after fracture. They exceeded normal contralateral values by 8 weeks after fracture. In the middle group, at 32 weeks of age, fractures were induced, and the femora were harvested at 6 and 12 weeks after fracture. At 6 weeks after fracture there was partial restoration of rigidity and breaking load. At 12 weeks after fracture, only the sham-operated rats had regained normal biomechanical values in their fractured femora, while the fractured femora of the ovariectomized rats remained significantly lower in both rigidity and breaking load. In contrast, for the oldest group of rats, 50 weeks old at fracture, neither sham-operated nor ovariectomized rats regained normal rigidity or breaking load in their fractured femora within the 24 weeks in which they were studied. In all fractured bones, there was a significant increase in BMD over the contralateral intact femora due to the increased bone tissue and bone mineral in the fracture callus. Ovariectomy significantly reduced the BMD of the intact femora and also reduced the gain in BMD by the fractured femora. In conclusion, age and ovariectomy significantly impair the process of fracture healing in female rats as judged by measurements of rigidity and breaking load in three-point bending and by accretion of mineral into the fracture callus.


Assuntos
Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Fraturas do Fêmur/fisiopatologia , Consolidação da Fratura/fisiologia , Ovariectomia , Resistência à Tração/fisiologia , Absorciometria de Fóton , Animais , Calo Ósseo/metabolismo , Feminino , Fraturas do Fêmur/metabolismo , Maleabilidade , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Suporte de Carga
20.
Nurse Educ Today ; 21(5): 391-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11403586

RESUMO

The concepts of collaboration and partnership currently have extensive impact upon health care providers and higher education institutions. One of the challenges is to develop networks which will foster partnerships able to react, and contribute, to an ever-evolving educational culture. These themes are illustrated by using the example of one school of nursing and midwifery, and the collective experience of a number of its academic staff. By focusing on distinct features of collaboration (strategic planning, origins of change, group dynamics and building a community), the authors seek to explore the impact of an educational culture in an attempt to provide meaning to their recent experiences. In so doing, group identity is explored and the prospect for creating partnerships across disciplines ('similarities rather than differences') is considered.


Assuntos
Docentes de Enfermagem/organização & administração , Relações Interprofissionais , Cultura Organizacional , Processos Grupais , Humanos , Inovação Organizacional , Escócia
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