Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 287
Filtrar
1.
Mol Ecol ; 32(15): 4329-4347, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37222024

RESUMO

Hybridisation and gene flow can have both deleterious and adaptive consequences for natural populations and species. To better understand the extent of hybridisation in nature and the balance between its beneficial and deleterious outcomes in a changing environment, information on naturally hybridising nonmodel organisms is needed. This requires the characterisation of the structure and extent of natural hybrid zones. Here, we study natural populations of five keystone mound-building wood ant species in the Formica rufa group across Finland. No genomic studies across the species group exist, and the extent of hybridisation and genomic differentiation in sympatry is unknown. Combining genome-wide and morphological data, we demonstrate more extensive hybridisation than was previously detected between all five species in Finland. Specifically, we reveal a mosaic hybrid zone between Formica aquilonia, F. rufa and F. polyctena, comprising further generation hybrid populations. Despite this, we find that F. rufa, F. aquilonia, F. lugubris and F. pratensis form distinct gene pools in Finland. We also find that hybrids occupy warmer microhabitats than the nonadmixed populations of cold-adapted F. aquilonia, and suggest that warm winters and springs, in particular, may benefit hybrids over F. aquilonia, the most abundant F. rufa group species in Finland. In summary, our results indicate that extensive hybridisation may create adaptive potential that could promote wood ant persistence in a changing climate. Additionally, they highlight the potentially significant ecological and evolutionary consequences of extensive mosaic hybrid zones, within which independent hybrid populations face an array of ecological and intrinsic selection pressures.


Assuntos
Formigas , Fluxo Gênico , Animais , Fluxo Gênico/genética , Hibridização Genética , Finlândia , Clima , Formigas/genética
2.
Vestn Oftalmol ; 136(5): 77-86, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33056967

RESUMO

PURPOSE: To evaluate biocompatibility of the new keratoprosthesis supporting plates (KSP) in rabbits in vivo. MATERIAL AND METHODS: The study included 15 chinchilla rabbits. In the first group (5 rabbit eyes) KSP made of hydrophobic acryl with square penetrating holes of 220×220 micron (model 1) were inserted into rabbits' corneas. In the second group (5 eyes), KSP made of hydrophobic acryl were used that had trapezoidal fenestrations with size (from 170×130 micron to 180×70 microns) gradually changing from periphery to the center of KSP (model 2). The control group rabbits (5 eyes) had 1/2 of Fyodorov-Zuev KSP made of titanium implanted. All animals were observed for up to 3 months with biomicroscopy and optical coherence tomography of the anterior segment. The animals were then euthanized and had their corneo-scleral discs excised and then examined with optical microscopy and scanning electron microscopy (SEM). RESULTS: After 3 months, there was only one case of KSP protrusion in the first group. In the second group, thinning of the corneal layers above the central part of KSP occurred in one case. The presence of polymer KSP (of both models) in the corneal stroma was found not to cause formation of rough fibrotic tissue. At the same time, adhered cellular and fibrous elements were discovered on the surface and inside the holes of the polymer KSP, while on the surface of the titanium plate cellular elements were absent. CONCLUSION: Supporting plates made of hydrophobic acrylic material can potentially serve as a foundation for the new keratoprosthesis design.


Assuntos
Córnea , Próteses e Implantes , Animais , Córnea/diagnóstico por imagem , Córnea/cirurgia , Substância Própria , Coelhos , Tomografia de Coerência Óptica
3.
Mol Oral Microbiol ; 32(5): 375-389, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28296262

RESUMO

Treponema denticola is an oral spirochete strongly associated with severe periodontal disease. A prominent virulence factor, the major outer sheath protein (Msp), disorients neutrophil chemotaxis by altering the cellular phosphoinositide balance, leading to impairment of downstream chemotactic events including actin rearrangement, Rac1 activation, and Akt activation in response to chemoattractant stimulation. The specific regions of Msp responsible for interactions with neutrophils remain unknown. In this study, we investigated the inhibitory effect of truncated Msp regions on neutrophil chemotaxis and associated signaling pathways. Murine neutrophils were treated with recombinant protein truncations followed by assessment of chemotaxis and associated signal pathway activation. Chemotaxis assays indicate sequences within the C-terminal region; particularly the first 130 amino acids, have the strongest inhibitory effect on neutrophil chemotaxis. Neutrophils incubated with the C-terminal region protein also demonstrated the greatest inhibition of Rac1 activation, increased phosphoinositide phosphatase activity, and decreased Akt activation; orchestrating impairment of chemotaxis. Furthermore, incubation with antibodies specific to only the C-terminal region blocked the Msp-induced inhibition of chemotaxis and denaturing the protein restored Rac1 activation. Msp from the strain OTK, with numerous amino acid substitutions throughout the polypeptide, including the C-terminal region compared with strain 35405, showed increased ability to impair neutrophil chemotaxis. Collectively, these results indicate that the C-terminal region of Msp is the most potent region to modulate neutrophil chemotactic signaling and that specific sequences and structures are likely to be required. Knowledge of how spirochetes dampen the neutrophil response is limited and Msp may represent a novel therapeutic target for periodontal disease.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Quimiotaxia de Leucócito/efeitos dos fármacos , Neutrófilos/fisiologia , Porinas/química , Porinas/metabolismo , Treponema denticola/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Interações Hospedeiro-Patógeno , Camundongos , Neuropeptídeos/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Porinas/genética , Porinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Treponema denticola/efeitos dos fármacos , Treponema denticola/imunologia , Fatores de Virulência , Proteínas rac1 de Ligação ao GTP/metabolismo
5.
Leukemia ; 30(8): 1701-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27211272

RESUMO

Ruxolitinib is a Janus kinase (JAK) (JAK1/JAK2) inhibitor that has demonstrated superiority over placebo and best available therapy (BAT) in the Controlled Myelofibrosis Study with Oral JAK Inhibitor Treatment (COMFORT) studies. COMFORT-II was a randomized (2:1), open-label phase 3 study in patients with myelofibrosis; patients randomized to BAT could crossover to ruxolitinib upon protocol-defined disease progression or after the primary end point, confounding long-term comparisons. At week 48, 28% (41/146) of patients randomized to ruxolitinib achieved ⩾35% decrease in spleen volume (primary end point) compared with no patients on BAT (P<0.001). Among the 78 patients (53.4%) in the ruxolitinib arm who achieved ⩾35% reductions in spleen volume at any time, the probability of maintaining response was 0.48 (95% confidence interval (CI), 0.35-0.60) at 5 years (median, 3.2 years). Median overall survival was not reached in the ruxolitinib arm and was 4.1 years in the BAT arm. There was a 33% reduction in risk of death with ruxolitinib compared with BAT by intent-to-treat analysis (hazard ratio (HR)=0.67; 95% CI, 0.44-1.02; P=0.06); the crossover-corrected HR was 0.44 (95% CI, 0.18-1.04; P=0.06). There was no unexpected increased incidence of adverse events with longer exposure. This final analysis showed that spleen volume reductions with ruxolitinib were maintained with continued therapy and may be associated with survival benefits.


Assuntos
Mielofibrose Primária/tratamento farmacológico , Pirazóis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Tamanho do Órgão/efeitos dos fármacos , Mielofibrose Primária/mortalidade , Pirimidinas , Baço , Taxa de Sobrevida
6.
Environ Entomol ; 44(3): 780-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26313984

RESUMO

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama is a key pest of citrus due to its role as vector of citrus greening disease or "huanglongbing." ACP monitoring is considered an indispensable tool for management of vector and disease. In the present study, datasets collected between 2009 and 2013 from 245 citrus blocks were used to evaluate precision, sensitivity for detection, and efficiency of five sampling methods. The number of samples needed to reach a 0.25 standard error-mean ratio was estimated using Taylor's power law and used to compare precision among sampling methods. Comparison of detection sensitivity and time expenditure (cost) between stem-tap and other sampling methodologies conducted consecutively at the same location were also assessed. Stem-tap sampling was the most efficient sampling method when ACP densities were moderate to high and served as the basis for comparison with all other methods. Protocols that grouped trees near randomly selected locations across the block were more efficient than sampling trees at random across the block. Sweep net sampling was similar to stem-taps in number of captures per sampled unit, but less precise at any ACP density. Yellow sticky traps were 14 times more sensitive than stem-taps but much more time consuming and thus less efficient except at very low population densities. Visual sampling was efficient for detecting and monitoring ACP at low densities. Suction sampling was time consuming and taxing but the most sensitive of all methods for detection of sparse populations. This information can be used to optimize ACP monitoring efforts.


Assuntos
Citrus , Hemípteros/fisiologia , Controle de Insetos/métodos , Animais , Citrus/crescimento & desenvolvimento , Florida , Densidade Demográfica
7.
J Agric Food Chem ; 61(50): 12327-32, 2013 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-24274620

RESUMO

Variability of physical properties across hides and skins requires careful consideration when manufacturing goods from leather. Therefore, an understanding of the extent of this variation and its nanostructural basis is useful. Tear strength tests were performed on ovine leather from a grid of 81 positions on skins. Synchrotron small-angle X-ray scattering measurements were made from three positions on the skin, from 26 skins. The X-ray structural measurements are compared with tear strengths of the samples. It is found that the thickness normalized tear strength does not vary greatly between different positions on the skin, in contrast to bovine hides. There is more variation between different skins than within the same skin. The collagen fibril orientation and orientation index, which has previously been shown to be correlated with tear strength, do not vary significantly between the different sampling positions in ovine skins. The collagen fibril orientation varies through the thickness of the skin in a consistent way. The consistency of collagen orientation in ovine leather between different positions on the skin is in marked contrast to bovine hides and informs the use of ovine leather for manufacturing applications.


Assuntos
Colágeno/química , Ovinos/metabolismo , Pele/química , Animais , Colágeno/metabolismo , Espalhamento a Baixo Ângulo , Resistência ao Cisalhamento , Pele/metabolismo
8.
Intern Med J ; 36(8): 530-3, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16866660

RESUMO

Mitochondrial DNA (mtDNA) haplogroups are 'neutral polymorphisms' in the mtDNA genome, which have accumulated and persisted along maternal lineages as the human population has migrated worldwide. Three ethnically distinct lineages of human mtDNA populations have been identified: European, characterized by nine haplogroups H, I, J, K, T, U, V, W and X; African, characterized by superhaplogroup L and Asian, characterized by superhaplogroup M. We studied the prevalence of mtDNA haplogroups in participants of the Blue Mountains Eye Study, a large population-based survey of vision conducted between 1991 and 2000 of non-institutionalized permanent residents aged 49 years or older from two suburban postcode areas, west of Sydney, Australia. Total DNA isolated from either hair follicles or blood was available for 3377 of the 3509 participants (96.2%) to determine mtDNA haplogroups by polymerase chain reaction/restriction fragment length polymorphism analysis. Approximately 94.2% of samples could be assigned to one of the nine major European haplogroups, whereas a further 1.2% included the African (L) and Asian (M) superhaplogroups. The five principal haplogroups represented were H (42.9%), U (14.1%), J (10.7%), T (9.2%) and K (8.1%), which together included 85% of this population.


Assuntos
DNA Mitocondrial/genética , Haplótipos/genética , Grupos Raciais/genética , Feminino , Marcadores Genéticos/genética , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales , Polimorfismo Genético/genética , Prevalência
9.
Mol Biol Cell ; 16(7): 3323-33, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15872085

RESUMO

The ability to undergo self-renewal is a defining characteristic of stem cells. Self-replenishing activity sustains tissue homeostasis and regeneration. In addition, stem cell therapy strategies require a heightened understanding of the basis of the self-renewal process to enable researchers and clinicians to obtain sufficient numbers of undifferentiated stem cells for cell and gene therapy. Here, we used postnatal muscle-derived stem cells to test the basic biological assumption of unlimited stem cell replication. Muscle-derived stem cells (MDSCs) expanded for 300 population doublings (PDs) showed no indication of replicative senescence. MDSCs preserved their phenotype (ScaI+/CD34+/desmin(low)) for 200 PDs and were capable of serial transplantation into the skeletal muscle of mdx mice, which model Duchenne muscular dystrophy. MDSCs expanded to this level exhibited high skeletal muscle regeneration comparable with that exhibited by minimally expanded cells. Expansion beyond 200 PDs resulted in lower muscle regeneration, loss of CD34 expression, loss of myogenic activity, and increased growth on soft agar, suggestive of inevitable cell aging attributable to expansion and possible transformation of the MDSCs. Although these results raise questions as to whether cellular transformations derive from cell culturing or provide evidence of cancer stem cells, they establish the remarkable long-term self-renewal and regeneration capacity of postnatal MDSCs.


Assuntos
Músculos/citologia , Células-Tronco/citologia , Envelhecimento , Animais , Antígenos CD34/biossíntese , Ataxina-1 , Ataxinas , Diferenciação Celular , Proliferação de Células , Transplante de Células , Células Cultivadas , Citometria de Fluxo , Marcadores Genéticos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Imunofenotipagem , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Camundongos SCID , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Músculos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Fenótipo , Regeneração , Células-Tronco/metabolismo , Fatores de Tempo
10.
Intern Med J ; 35(5): 300-2, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15845114

RESUMO

Several thrombolytic agents for the treatment of acute ischaemic stroke have been examined; however, to date, only the i.v. administration of recombinant tissue plasminogen activator is licensed in Australia. Although no trials directly comparing intra-arterial and i.v. delivery of thrombolytics exist, intra-arterial thrombolysis has several potential advantages, including angiographic assessment of the thrombus and the site of occlusion and collateral circulation, improved recanalization, and delivery of higher local concentrations of thrombolytic agents and extending the therapeutic time window for treatment. We conducted a retrospective audit of our experience with the use of intra-arterial urokinase to treat acute ischaemic stroke at an Australian tertiary-care hospital between June 1993 and June 2003. We examined time from stroke onset to assessment, computerized tomography scan, cerebral angiography and thrombolysis, anatomical classification of intra-arterial thrombus, rates of symptomatic intracerebral haemorrhage, and clinical outcome at 3 months. We believe that in carefully selected individuals in appropriate centres of expertise, intra-arterial thrombolytic therapy holds great promise.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Infarto Cerebral/tratamento farmacológico , Ativadores de Plasminogênio/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Infarto da Artéria Cerebral Anterior/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Pessoa de Meia-Idade , Insuficiência Vertebrobasilar/tratamento farmacológico
13.
J Nat Prod ; 64(12): 1541-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11754607

RESUMO

A new approach to the use of commercial databases for the dereplication of purified natural products has been developed. This is based on searching a text file that links each structure with its molecular weight and an exact count of the number of methyl, methylene, and methine groups it contains. Analysis of such a text file, constructed from a database containing more than 126,000 natural product structures, revealed that these data, readily measured using MS and NMR spectroscopy, are highly discriminating. The identification of an alkaloid and a sesquiterpene using this new approach is described.


Assuntos
Alcaloides/química , Alcaloides de Amaryllidaceae , Produtos Biológicos , Bases de Dados Factuais , Sesquiterpenos/química , Alcaloides/análise , Técnicas de Química Combinatória , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Concentração Inibidora 50 , Espectrometria de Massas , Estrutura Molecular , Peso Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/análise , Software , Estereoisomerismo
14.
Pharmacol Toxicol ; 87(4): 179-81, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11097272

RESUMO

A higher efficiency of cadmium binding with racemic than with meso-2,3-dimercaptosuccinic acid (rac-DMSA; meso-DMSA) was found in an in vitro speciation model by Fang et al. (1996). This finding has not yet been tested in vivo. This paper presents results on mobilisation of cadmium by meso- and rac-DMSA in rats. Cadmium chloride was administered as the radioactive isotope 109Cd intraperitoneally to all animals. One group was an untreated control and two groups were treated with meso- and rac-DMSA, respectively. Treatment with chelators was applied twice, immediately after 109Cd and 24 hr afterwards intraperitoneally at the dose of 1 mmol/kg, each. Six days later radioactivity was measured in the liver and kidneys. Whole-body counting was carried out on days 1, 2, 3 and 6 of the experiment. At the end of the experiment, both treatments caused a decrease in 109Cd whole-body retention with rac-DMSA being more efficient (decrease from 83% in control to 74% and 64% in groups treated with meso- and rac-DMSA, respectively). The same reduction of 109Cd was obtained by both chelators in the liver (from 57% to about 47%). In the kidney only rac-DMSA produced significant reduction of 109Cd (from 5.3% to 3.5%). In conclusion, these results show modest reduction of cadmium in the body by two isoforms of DMSA with rac-DMSA being slightly more efficient than meso-DMSA.


Assuntos
Cádmio/metabolismo , Quelantes/farmacologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Succímero/farmacologia , Análise de Variância , Animais , Cádmio/administração & dosagem , Feminino , Injeções Intraperitoneais , Rim/metabolismo , Fígado/metabolismo , Ratos , Ratos Wistar , Estereoisomerismo
15.
Int J Radiat Biol ; 76(10): 1409-15, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11057750

RESUMO

PURPOSE: To reduce retention and toxicity of the alpha particle emitter polonium-210 in rats by newly developed chelating agents. MATERIALS AND METHODS: Repeated subcutaneous chelation was conducted after intravenous injection of 210Po nitrate. For reduction of 210Po retention the treatment with vicinal dithiols meso-and rac-2,3-dimercaptosuccinic acid (DMSA), mono-i-amylmeso-2,3-dimercapto succinate (Mi-ADMS) and mono-N-(i-butyl)-meso-2,3-dimercapto succinamide (Mi-BDMA) were used. For the reduction of toxic effects of 210Po, treatment effectiveness of Mi-BDMA was compared with that of N,N'-di(2-hydroxyethyl)ethylenediamine-N,N'-biscarbodithioate (HOEtTTC, reference compound). RESULTS: Treatment with meso-DMSA and rac-DMSA altered the main excretion route of 210Po, reduced its contents in the liver but increased its deposition in the kidneys. Treatment with Mi-ADMS or Mi-BDMA increased total excretion of 210Po, mainly via the faeces. Only Mi-BDMA decreased 210Po levels in the kidneys. The effectiveness of all chelators decreased with delay in the start of treatment. In a survival study, the lives of rats treated early with Mi-BDMA or delayed with HOEtTTC were prolonged three-fold when compared with rats receiving a lethal amount of 210Po only. CONCLUSIONS: Of the vicinal dithiols examined, Mi-BDMA was the best mobilizing chelating agent for 210Po and it reduced 210Po toxicity when the treatment started immediately. However, the detoxification efficacy of the immediate treatment with HOEtTTC, observed in our previous study, was superior to that of the present result with Mi-BDMA.


Assuntos
Quelantes/farmacologia , Polônio/farmacocinética , Succímero/farmacologia , Animais , Feminino , Inativação Metabólica , Ratos , Ratos Wistar , Estereoisomerismo , Distribuição Tecidual
16.
Biol Trace Elem Res ; 74(2): 127-39, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-11051587

RESUMO

D-Penicillamine (DPA) is effective in the treatment of Wilson's disease, whereas zinc salts are also used as a therapy for this disorder of copper transport. Recently, it has been shown that the copper chelators 1,4,7,11-tetraazaundecane tetrahydrochloride (TAUD) and tetraethylenepentamine pentahydrochloride (TETREN) could be useful for copper mobilization in rats. Because these agents could be potential clinical alternatives to DPA for patients with Wilson's disease who are intolerant to this drug, we examined whether oral administration of TAUD and TETREN could be effective in mobilizing copper in experimental copper-overloaded rats. The efficacy of a combined administration of zinc and DPA, TAUD, or TETREN was also assessed. Rats were copper loaded with 0.125% copper acetate in water for 12 wk. After this period, DPA, TAUD, and TETREN were administered by gavage at 0.67 mmol/kg/d for 5 d, and zinc was given at 2.5 mg Zn/kg/d. Twelve weeks of copper loading resulted in a 32-fold increase in total hepatic copper. TETREN was the most effective chelator in increasing the urinary excretion of copper. However, it did not reduce significantly the hepatic copper levels. In turn, combined administration of zinc and chelating agents significantly reduced the amount of copper found in the feces. Although TAUD and TETREN showed a similar or higher efficacy to DPA in mobilizing copper, concurrent treatment of chelating agents and zinc salts should be discarded according to the current results.


Assuntos
Quelantes/uso terapêutico , Cobre/intoxicação , Animais , Cobre/urina , Etilenodiaminas/uso terapêutico , Fezes/química , Masculino , Penicilamina/uso terapêutico , Ratos , Ratos Sprague-Dawley , Zinco/uso terapêutico
17.
Toxicology ; 147(3): 151-6, 2000 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10924797

RESUMO

The hypothesis that two known chelators 1, 2-dimethyl-3-hydroxypyrid-4-one (L1) and desferrioxamine (DFO) might be more efficient as combined treatment than as monotherapies in removing aluminium from the body was tested in a new acute rat model. Five-week old female rats received chelators: L1 (p.o.), DFO (i.p.) or L1+DFO as 100 or 200 mg/kg dose half an hour after a single i.p. administration of 6 mg Al/kg body weight in the form of chloride. Serum aluminium concentration and urinary aluminium and iron excretions were determined by electrothermal or flame atomic absorption spectrometry. Both chelators were effective only at the higher dose level. While DFO was more effective than L1 in enhancing urinary aluminium excretion, L1 was more effective than DFO in enhancing urinary iron excretion. In the combined treatment group L1 did not increase the DFO effect on aluminium and DFO did not increase the effect of L1 on iron elimination. However, in this group a simultaneous increase in both aluminium and iron elimination was observed. Our results support the usefulness of this animal model for preliminary in vivo testing of aluminium chelators. Urinary values were more useful because of the high variability of serum results. Result of combined chelators treatment should be confirmed in a different experimental model before extrapolation to other systems. This testing procedure of course does not provide all the relevant answers for evaluating the efficiency of chelating agents in aluminium toxicity.


Assuntos
Alumínio/sangue , Alumínio/urina , Quelantes/farmacologia , Desferroxamina/farmacologia , Quelantes de Ferro/farmacologia , Piridonas/farmacologia , Alumínio/administração & dosagem , Animais , Deferiprona , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Ferro/sangue , Ferro/urina , Ratos , Ratos Wistar
18.
Toxicology ; 137(3): 161-8, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10522496

RESUMO

The influence of age at which aluminum (Al) exposure was initiated on the efficacy of chelation therapy in mobilizing Al was investigated in two groups of male rats exposed to this element at two different stages of the life cycle. Young (21 days old) and old (18 months) rats were exposed to 0 and 50 mg Al/kg/day administered as Al nitrate in drinking water for a preliminary period of 14 days followed by a period of 100 days, in which Al-exposed animals received 100 mg Al/kg/day. At the end of the period of exposure, Al-loaded rats in each age group were given one of the following treatments: s.c. deferoxamine (DFO), oral 1,2-dimethyl-3-hydroxypyrid-4-one (L1) and 1-(p-methylbenzyl)-2-ethyl-3-hydroxypyrid-4-one (MeBzEM) at doses of 0.89 mmol/kg/day for 5 consecutive days. Another group of Al-exposed rats received a concurrent administration of s.c. DFO and oral L1 both at 0.45 mmol/kg/day. During chelation therapy urines were collected daily. Control groups included rats exposed and unexposed to Al. Oral administration of L1 was the most effective treatment in enhancing urinary Al excretion in both age groups of Al-loaded rats. This beneficial effect was similar for old and young animals. Concurrent administration of DFO and L1 had no advantages over the use of either single agent, while MeBzEM was not effective in mobilizing Al from Al-exposed rats.


Assuntos
Envelhecimento/metabolismo , Alumínio/farmacocinética , Quelantes/farmacologia , Terapia por Quelação , Alumínio/urina , Animais , Antídotos/farmacologia , Deferiprona , Desferroxamina/farmacologia , Masculino , Piridinas/farmacologia , Piridonas/farmacologia , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
19.
Ann Pharmacother ; 33(7-8): 850-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10466915

RESUMO

OBJECTIVE: To describe an innovative, interdisciplinary approach to illustrate the relationship between healthcare ethics and law. METHODS: A mock trial was created for students enrolled in the Samford University McWhorter School of Pharmacy and Department of Paralegal Education. The trial served as the starting point to discuss confidentiality in health care in general and pharmacy in particular. Students from both programs served on the jury and rendered a verdict after the case had been presented. The Alabama statute concerning exceptions to confidentiality is reviewed. The students' assignment and lessons learned are also described. SUMMARY: Students thoroughly enjoyed this method of teaching and learning. The mock trial provided an interesting way to exemplify the often complex relationship between healthcare ethics and law.


Assuntos
Confidencialidade , Educação em Farmácia/métodos , Ética Farmacêutica/educação , Legislação Farmacêutica , Responsabilidade pela Informação , Soropositividade para HIV , Comunicação Interdisciplinar , Ensino
20.
J Appl Toxicol ; 19(3): 143-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10362263

RESUMO

The very young are more prone to lead poisoning than adults, and the treatment with chelating agents, either as monotherapy or combined treatment, is still a matter of dispute. The purpose of this work was to evaluate the efficiency of three chelating agents administered either as monotherapies or as combined treatments in sucklings. Lead acetate (5 mg Pb kg(-1) i.p.) was administered to the 7-day-old rat pups in eight litters on experimental day 1 and chelating agents on experimental days 2 and 3. Pups were divided into six groups: (1) untreated control; (2) EDTA (calcium disodium ethylendiaminetetraacetate, 0.3 mmol kg(-1) i.p. at 4 p.m.); (3) meso-DMSA (meso-2,3-dimeracaptosuccinic acid, 0.5 mmol kg(-1) p.o. at 10 a.m.); (4) rac-DMSA (racemic-2,3-dimeracaptosuccinic acid, 0.5 mmol kg(-1) p.o. at 10 a.m.); (5) EDTA+meso-DMSA; and (6) EDTA+rac-DMSA. Rats were killed on experimental day 5. Tissue element concentrations were analyzed by atomic absorption spectrometry. Treatment with EDTA did not affect tissue Pb, but it reduced Zn in the carcass and liver. Meso-DMSA reduced Pb in the kidneys and brain, and it did not affect organ essential elements. Rac-DMSA most efficiently reduced Pb concentrations in the carcass, kidneys and brain, but it also reduced Zn and Cu in the liver and Zn in the kidneys. Combined treatments with EDTA never improved the efficiency of either DMSA isoform in decreasing tissue Pb but they did reduce tissue Zn concentrations. All treatments caused the same decrease in the carcass Ca concentrations. The results do not support combined treatment in this age group, which is especially sensitive to trace element deficiencies, and suggest that meso-DMSA might be the treatment of choice in acute lead poisoning in infants.


Assuntos
Quelantes/uso terapêutico , Ácido Edético/uso terapêutico , Intoxicação por Chumbo/prevenção & controle , Chumbo/metabolismo , Succímero/uso terapêutico , Animais , Animais Lactentes , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cálcio/metabolismo , Quimioterapia Combinada , Feminino , Ferro/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Chumbo/toxicidade , Intoxicação por Chumbo/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Estereoisomerismo , Succímero/química , Zinco/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...