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1.
Clin Otolaryngol ; 43(1): 223-229, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28734109

RESUMO

OBJECTIVES: To estimate the total costs of treating head and neck cancers, specifically oropharyngeal, laryngeal and oral cavity cancer, in secondary care facilities in England during the period 2006/2007 to 2010/2011. DESIGN: Patient records were extracted from an English hospital database to estimate the number of patients treated for oropharyngeal, laryngeal and oral cavity cancer in England. Identified resource use was linked to published United Kingdom cost estimates to quantify the reimbursement of treatment through the Payment by Results system. SETTING: Retrospective hospital data analysis. PARTICIPANTS: From the hospital data, patient records of patients treated for oropharyngeal, laryngeal and oral cavity cancer were selected. MAIN OUTCOME MEASURES: Annual total costs of treatment, stratified by inpatient and outpatient setting and by male and female patients. RESULTS: From 2006/2007 to 2010/2011, total costs of treatment across the three head and neck cancer sites were estimated to be approximately £309 million, with 90% attributable to inpatient care (bundled costs). Oropharyngeal cancer accounted for 37% of total costs. Costs and patient numbers increased over time, largely due to a rise in oropharyngeal cancer, where total costs increased from £17.21 million to £30.32 million, with over 1400 (52%) more inpatients treated in 2010/11 compared to 2006/07. CONCLUSIONS: In 4 years, the number of patients with oropharyngeal cancer receiving some form of inpatient care increased by more than half, and associated costs increased by three quarters. This reinforces the case for prevention and early detection strategies to help contain this epidemiological and economic burden.


Assuntos
Efeitos Psicossociais da Doença , Gastos em Saúde/tendências , Neoplasias Orofaríngeas/economia , Terapia Combinada/economia , Bases de Dados Factuais , Inglaterra , Humanos , Neoplasias Orofaríngeas/terapia , Estudos Retrospectivos
3.
Mol Cell Biol ; 10(9): 4456-65, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2388614

RESUMO

N6-methyladenosine (m6A) residues occur at internal positions in most cellular and viral RNAs; both heterogeneous nuclear RNA and mRNA are involved. This modification arises by enzymatic transfer of a methyl group from S-adenosylmethionine to the central adenosine residue in the canonical sequence G/AAC. Thus far, m6A has been mapped to specific locations in eucaryotic mRNA and viral genomic RNA. We have now examined an intron-specific sequence of a modified bovine prolactin precursor RNA for the presence of this methylated nucleotide by using both transfected-cell systems and a cell-free system capable of methylating mRNA transcripts in vitro. The results indicate the final intron-specific sequence (intron D) of a prolactin RNA molecule does indeed possess m6A residues. When mapped to specific T1 oligonucleotides, the predominant site of methylation was found to be within the consensus sequence AGm6ACU. The level of m6A at this site is nonstoichiometric; approximately 24% of the molecules are modified in vivo. Methylation was detected at markedly reduced levels at other consensus sites within the intron but not in T1 oligonucleotides which do not contain either AAC or GAC consensus sequences. In an attempt to correlate mRNA methylation with processing, stably transfected CHO cells expressing augmented levels of bovine prolactin were treated with neplanocin A, an inhibitor of methylation. Under these conditions, the relative steady-state levels of the intron-containing nuclear precursor increased four to six times that found in control cells.


Assuntos
Adenosina/análogos & derivados , Íntrons , Prolactina/genética , Precursores de RNA/genética , Adenosina/análise , Animais , Sequência de Bases , Bovinos , Núcleo Celular/metabolismo , Éxons , Cinética , Metilação , Dados de Sequência Molecular , Plasmídeos , RNA Mensageiro/genética , Mapeamento por Restrição , Transcrição Gênica
4.
Mol Cell Biol ; 11(9): 4779-85, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1678857

RESUMO

Extrachromosomal elements are common early intermediates of gene amplification in vivo and in cell culture. The time at which several extrachromosomal elements replicate was compared with that of the corresponding amplified or unamplified chromosomal sequences. The replication timing analysis employed a retroactive synchrony method in which fluorescence-activated cell sorting was used to obtain cells at different stages of the cell cycle. Extrachromosomally amplified Syrian hamster CAD genes (CAD is an acronym for the single gene which encodes the trifunctional protein which catalyzes the first three steps of uridine biosynthesis) replicated in a narrow window of early S-phase which was approximately the same as that of chromosomally amplified CAD genes. Similarly, extrachromosomally amplified mouse adenosine deaminase genes replicated at a discrete time in early S-phase which approximated the replication time of the unamplified adenosine deaminase gene. In contrast, the multicopy extrachromosomal Epstein-Barr virus genome replicated within a narrow window in late S-phase in latently infected human Rajii cells. The data indicate that localization within a chromosome is not required for the maintenance of replication timing control.


Assuntos
Replicação do DNA , Amplificação de Genes , Adenosina Desaminase/genética , Animais , Aspartato Carbamoiltransferase/genética , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/genética , Ciclo Celular , Linhagem Celular , Cricetinae , Di-Hidro-Orotase/genética , Citometria de Fluxo , Herpesvirus Humano 4/genética , Cinética , Mesocricetus , Camundongos , Complexos Multienzimáticos/genética , Plasmídeos/genética
5.
Mol Cell Biol ; 8(11): 4745-55, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3211127

RESUMO

The adult Schistosoma mansoni cDNA clone 10-3 encodes an antigen that is recognized by sera from infected humans. We characterized multiple developmentally regulated transcripts homologous to the 10-3 cDNA and portions of the complex genomic loci encoding those transcripts. Transcripts of approximately 950, 870, and 780 nucleotides were expressed in adults, whereas only the 780-nucleotide transcript was observed in the larval stage. These transcripts were highly similar, containing variable numbers of identical direct tandem repeats of 81 bases. Although the sequence of the repeating elements and sequences 3' to them were identical in all the transcripts, sequences 5' of the repeating elements exhibited variations, including a 27-base insertion, alternative start sites for transcription, and alternate 5' exon usage. These transcripts appeared to be derived in part by the developmentally controlled alternative splicing of small exons and the use of alternative transcription initiation sites from the one or two complex loci of at least 40 kilobase pairs. Each 81-base repeat in the transcripts was encoded by three dispersed 27-base-pair exons. These 27-base-pair exons were contained within highly conserved, reiterated 3-kilobase-pair genomic tandem arrays.


Assuntos
Éxons , Sequências Repetitivas de Ácido Nucleico , Schistosoma mansoni/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA/genética , Regulação da Expressão Gênica , Íntrons , Dados de Sequência Molecular , RNA Mensageiro/genética , Mapeamento por Restrição , Schistosoma mansoni/crescimento & desenvolvimento , Transcrição Gênica
6.
Mol Cell Biol ; 13(5): 2971-81, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8474455

RESUMO

Gene amplification is frequently mediated by the initial production of acentric, autonomously replicating extrachromosomal elements. The 4,000 extrachromosomal copies of the mouse adenosine deaminase (ADA) amplicon in B-1/50 cells initiate their replication remarkably synchronously in early S phase and at approximately the same time as the single-copy chromosomal locus from which they were derived. The abundance of ADA sequences and favorable replication timing characteristics in this system led us to determine whether DNA replication initiates in ADA episomes within a preferred region and whether this region is the same as that used at the corresponding chromosomal locus prior to amplification. This study reports the detection and localization of a discrete set of DNA fragments in the ADA amplicon which label soon after release of synchronized B-1/50 cells into S phase. A switch in template strand complementarity of Okazaki fragments, indicative of the initiation of bidirectional DNA replication, was found to lie within the same region. This putative replication origin is located approximately 28.5 kbp upstream of the 5' end of the ADA gene. The same region initiated DNA replication in the single-copy ADA locus of the parental cells. These analyses provide the first evidence that the replication of episomal intermediates involved in gene amplification initiates within a preferred region and that the same region is used to initiate DNA synthesis within the native locus.


Assuntos
Adenosina Desaminase/genética , Replicação do DNA , DNA/genética , Amplificação de Genes , Animais , Afidicolina/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Clonagem Molecular , Cosmídeos , DNA/isolamento & purificação , DNA/metabolismo , Sondas de DNA , Biblioteca Gênica , Camundongos , Plasmídeos , Sequências Repetitivas de Ácido Nucleico , Transcrição Gênica
7.
Mol Cell Biol ; 7(5): 1740-50, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-2885742

RESUMO

In a previous study (G. M. Wahl, B. Robert de Saint Vincent, and M. L. De Rose, Nature (London) 307:516-520, 1984), we used gene transfer of a CAD cosmid to demonstrate that gene position profoundly affects amplification frequency. One transformant, T5, amplified the donated CAD genes at a frequency at least 100-fold higher than did the other transformants analyzed. The CAD genes in T5 and two drug-resistant derivatives were chromosomally located. In this report, we show that a subclone of T5 gives rise to an extrachromosomal molecule (CAD episome) containing the donated CAD genes. Gel electrophoresis indicated that the CAD episome is approximately 250 to 300 kilobase pairs, and a variety of methods showed that it is a covalently closed circle. We show that the CAD episome replicates semiconservatively and approximately once per cell cycle. Since the CAD cosmid, which comprises most of the CAD episome, does not replicate autonomously when transfected into cells, our results indicate that either the process which generated the episome resulted in a cellular origin of DNA replication being linked to the CAD sequences or specific rearrangements within the episome generated a functional origin. The implications of these results for mechanisms of gene amplification and the genesis of minute chromosomes are discussed.


Assuntos
Replicação do DNA , Amplificação de Genes , Genes Reguladores , Complexos Multienzimáticos/genética , Plasmídeos , Proteínas/genética , Animais , Aspartato Carbamoiltransferase/genética , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/genética , Mapeamento Cromossômico , Cosmídeos , Cricetinae , Enzimas de Restrição do DNA , Di-Hidro-Orotase/genética , Cariotipagem , Transfecção
8.
Mol Cell Biol ; 8(4): 1525-33, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2898098

RESUMO

Recent experiments have shown that gene amplification can be mediated by submicroscopic, autonomously replicating, circular extrachromosomal molecules. We refer to those molecules as episomes (S. Carroll, P. Gaudray, M. L. DeRose, J. F. Emery, J. L. Meinkoth, E. Nakkim, M. Subler, D. D. Von Hoff, and G. M. Wahl, Mol. Cell. Biol. 7:1740-1750, 1987). The experiments reported in this paper explore the way episomes are formed and their fate in the cell over time. The data reveal that in our system the episomes are initially 250 kilobases, but gradually enlarge until they become double minute chromosomes. In addition, we show that episomes or double minute chromosomes can integrate into chromosomes. Our results also suggest that episomes can be produced by deletion of the corresponding sequences from the chromosome.


Assuntos
Deleção Cromossômica , Cromossomos/fisiologia , Amplificação de Genes , Genes , Animais , Aspartato Carbamoiltransferase/genética , Carbamoil-Fosfato Sintase (Amônia)/genética , Di-Hidro-Orotase/genética , Cariotipagem , Plasmídeos
9.
J Dairy Sci ; 89(2): 640-50, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16428634

RESUMO

A novel whey protein emulsion gel (WPEG) complex was developed to protect dietary unsaturated fatty acids from rumen biohydrogenation with the goal of modifying the fatty acid composition of milk fat. Three experiments were conducted with WPEG complexes made from either whey protein concentrate containing 80% crude protein, whey protein isolate, or whey protein concentrate high-gel capacity. Each experiment lasted 3 wk. All cows received a basal total mixed ration (TMR). During wk 1 and 3, all cows received only the TMR. During wk 2, 3 control cows received 330 g/d of soybean oil added to the TMR, and the other 3 cows received 330 g/d of soybean oil in one of the WPEG complexes. During wk 2, C18:2 increased from 3.29 to 5.88 g/100 g of fat in Experiment 1, 2.91 to 7.42 g/100 g of fat in Experiment 2, and 3.57 to 6.56 g/100 g of fat in Experiment 3 for WPEG cows. Fatty acid C18:3 increased from 0.51 to 0.84, 0.52 to 1.15, and 0.51 to 0.97 g/100 g of fat for Experiments 1, 2, and 3, respectively, for WPEG cows. Higher proportions of C18:1 trans-9 in milk fat of control cows compared with WPEG cows were seen in all experiments. The proportion of C18:1 trans-11 was also higher in control cows in Experiments 1 and 2, but not in Experiment 3. The WPEG complexes successfully protected unsaturated fatty acids from rumen biohydrogenation and resulted in an increase in the unsaturated fatty acid composition of milk fat produced by Holstein cows without increasing the trans 18-carbon monoenes.


Assuntos
Bovinos/metabolismo , Gorduras Insaturadas na Dieta/metabolismo , Ácidos Graxos Insaturados/análise , Géis/administração & dosagem , Proteínas do Leite/administração & dosagem , Leite/química , Animais , Gorduras Insaturadas na Dieta/administração & dosagem , Emulsões/administração & dosagem , Emulsões/química , Gorduras/química , Ácidos Graxos/análise , Ácidos Graxos/sangue , Feminino , Géis/química , Hidrogenação , Reação de Maillard , Proteínas do Leite/química , Rúmen/metabolismo , Óleo de Soja/administração & dosagem , Óleo de Soja/química , Proteínas do Soro do Leite
10.
Int J STD AIDS ; 27(1): 51-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25681263

RESUMO

Genital warts, 90% of which are caused by human papillomavirus types 6 and 11, are a significant problem in the UK. The cost of managing genital warts was previously estimated at £52.4 million for 2010. The objective of this study was to estimate the cost of genital warts management up to 2012 in the UK and by jurisdiction. Population statistics and the number of reported genital warts cases in genito-urinary medicine clinics were obtained and extrapolated to 2012. Cases of genital warts treated in primary care were estimated from The Health Improvement Network database. The number of visits and therapy required were estimated by genito-urinary medicine experts. Costs were obtained from the appropriate national tariffs. The model estimated there were 220,875 genital warts cases in the UK in 2012, costing £58.44 million (£265/patient). It estimated 157,793 cases in England costing £41.74 million; 7468 cases in Scotland costing £1.90 million; 7095 cases in Wales costing £1.87 million; and 3621 cases in Northern Ireland costing £948,000. The full National Health Service costs for the management of genital warts have never previously been estimated separately for each jurisdiction. Findings reveal a significant economic burden, which is important to quantify when understanding the value of quadrivalent human papilloma virus vaccination.


Assuntos
Condiloma Acuminado/tratamento farmacológico , Condiloma Acuminado/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Condiloma Acuminado/diagnóstico , Feminino , Humanos , Masculino , Reino Unido
11.
Injury ; 47(10): 2266-2268, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27553391

RESUMO

Tag rugby is one of the fastest growing sports in Ireland. It is a soft-contact team game that is loosely based on the rugby league format except players try to remove Velcro tags from their opponents' shorts rather than engage in a typical rugby tackle. The purpose of this study was to examine all tag rugby associated hand injuries over a five-year period in three large tertiary referral hospitals in Ireland. Using the patient corresponding system, 228 patients with hand injury related tag rugby injuries were observed from 2010 to 2015. There were 138 males and 90 females in the study and over 40% of patients required surgery. Most of the patients were young professionals with an average age of 30. Twenty-five patients worked in the financial services whilst there were 23 teachers. Fractures accounted for 124 of the 228 injuries and mallet injuries accounted for 53. Eighty percent of all injuries occurred during the tackle. The mean number of days missed from work was 9.1±13.8 days. These injuries resulted in an average of seven hospital appointments per patient. Considering it is a soft-contact sport, it is surprising the number of hand injuries that we have observed. Although safety measures have been introduced to decrease the number of hand injuries in recent years, there is a need for further improvements. Better player education about seeking prompt medical attention once an injury occurs, coupled with longer shorts worn by players may improve measures for the sport.


Assuntos
Traumatismos em Atletas/epidemiologia , Futebol Americano/lesões , Fraturas Ósseas/epidemiologia , Traumatismos da Mão/epidemiologia , Lesões dos Tecidos Moles/epidemiologia , Adulto , Traumatismos em Atletas/cirurgia , Feminino , Fraturas Ósseas/cirurgia , Traumatismos da Mão/cirurgia , Humanos , Incidência , Irlanda/epidemiologia , Masculino , Estudos Retrospectivos , Lesões dos Tecidos Moles/cirurgia
12.
Meat Sci ; 70(2): 229-40, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22063479

RESUMO

The performance of a visual image analysis (VIA) system was tested with regards to its potential to determine in vivo carcass composition and conformation, either alone, or in conjunction with other in vivo measures such as live weight and backfat depth. Pigs of both sexes of a commercial type were reared and slaughtered at weights ranging from 50 to 120 kg. Feeding was ad libitum on diets ranging from 0.14 to 0.19 kgkg(-1) crude protein content to produce animals of a range of body condition. Two analyses were carried out: the first analysis addressed the relationship between dimensionless carcass and VIA indices; the second analysis assessed the relationship between carcass composition and VIA body shape using detrended carcass and VIA data, which were produced by removal of allometric growth trends. A statistically significant relationship (P<0.05) between in vivo VIA body size and shape and carcass muscle dimensions and composition was found for most body regions. Adjusted R(2) statistics ranged between 0.13 and 0.54 for relative fat weights and between 0.14 and 0.51 for relative lean weights. The predictive power of the regression models, indicated by R(2)-like statistics for prediction, was approximately 70% of the adjusted R(2) values. The descriptive and predictive powers of the corresponding models generally strengthened if VIA indices were combined with other in vivo measurements. The relationships between in vivo and carcass measures remained statistically significant (P<0.05) after removal of the growth trends, although adjusted R(2) statistics generally decreased. The predictive power of models corresponding to the detrended measures was, however, weak. The results show in vivo VIA measurements to be useful in the estimation of muscle size, carcass conformation and composition, all of which are of significant importance to the pig production, marketing and processing industries.

13.
Virus Res ; 3(2): 165-79, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-4060886

RESUMO

Influenza viruses of contrasting receptor specificity have been examined for their ability to infect receptor-modified MDCK cells containing sialyloligosaccharide receptor determinants of defined sequence. Cells were treated with sialidase to remove sialic acid and render them resistant to infection and were then incubated with sialyltransferase and CMP-sialic acid to restore sialic acid in the SA alpha 2,6Gal or SA alpha 2,3Gal linkages. The viruses A/RI/5 + /57 and A/duck/Ukraine/1/63, previously shown to exhibit preferential binding of SA alpha 2,6Gal and SA alpha 2,3Gal linkages, respectively, were found to exhibit differential infection of the receptor-modified cells in accord with their receptor specificity. Coinfection of SA alpha 2,3Gal derivatized cells with a mixture of the two viruses resulted in selective propagation of the SA alpha 2,3Gal-specific A/duck/Ukraine/1/63 virus. The results demonstrate the potential for cell surface receptors to mediate selection of receptor-specific variants of influenza virus.


Assuntos
Vírus da Influenza A/metabolismo , Oligossacarídeos/metabolismo , Receptores Virais/metabolismo , Adsorção , Animais , Anticorpos Antivirais/análise , Sítios de Ligação , Linhagem Celular , Cães , Eritrócitos/microbiologia , Hemaglutininas Virais , Vírus da Influenza A/imunologia , Rim , Neuraminidase/metabolismo , Receptores Virais/genética , Receptores Virais/imunologia , Ácidos Siálicos/metabolismo , Sialiltransferases/metabolismo , Especificidade da Espécie , Proteínas Virais/análise , beta-D-Galactosídeo alfa 2-6-Sialiltransferase
14.
Thromb Haemost ; 51(2): 222-7, 1984 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-6740554

RESUMO

Extracts of adult Ancylostoma ceylanicum prolonged the prothrombin time (PT) and partial thromboplastin time with kaolin ( PPTK ) of both human and dog plasmas in vitro. Excretory/secretory (E/S) products of these worms had similar effects while larval extract prolonged the PTTK only. Thus, the anticoagulant activities of this parasite are dependent upon the stage of the worm's life cycle. Collagen- and ADP-induced platelet aggregation were inhibited by adult and larval extracts. When the peripheral blood and bleeding times of dogs with varying worm burdens were examined, the only abnormality was shortening of the PTTK in the most heavily infected animals. Homogenates of dog small bowel subjacent to adult hookworms prolonged the PT of dog plasma and electron microscopical examination of this tissue revealed aggregation of platelets in blood venules without fibrin deposition. Thus, this study provides evidence that the anticoagulant properties of hookworms may have biological significance in infected animals.


Assuntos
Ancylostoma/análise , Ancilostomíase/sangue , Anticoagulantes/análise , Coagulação Sanguínea/efeitos dos fármacos , Animais , Tempo de Sangramento , Cães , Fibrinólise/efeitos dos fármacos , Humanos , Microscopia Eletrônica , Tempo de Tromboplastina Parcial , Agregação Plaquetária/efeitos dos fármacos , Tempo de Protrombina , Extratos de Tecidos/farmacologia
15.
J Neuroendocrinol ; 11(1): 63-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9918230

RESUMO

Serotonin (5-HT) plays a role in mediating the oestradiol-induced surge of luteinising hormone (LH), but so far the 5-HT receptor subtype involved has not been identified. Our previous in-situ hybridization and pharmacological studies suggest that the action of 5-HT involves the 5-HT2A receptor. The aim of the present study was to investigate this possibility by the direct approach of determining whether 5-HT2A receptor antagonists block the oestradiol-induced surge of luteinising hormone releasing hormone (LHRH). Adult female Wistar rats, which had shown at least two consecutive 4-day oestrous cycles, were ovariectomised under halothane anaesthesia in the morning of dioestrus and injected with vehicle (arachis oil) alone or oestradiol benzoate (OB). At 12.00 h of the next day, presumptive pro-oestrus, the animals were injected intraperitoneally with one of three 5-HT2A antagonists, a selective 5-HT reuptake inhibitor (fluoxetine), or the appropriate vehicles; hypophysial portal blood was then collected under alphaxalone anaesthesia between 15.00 and 19.00 h. The amount of LHRH released into hypophysial portal blood during consecutive 30-min periods was determined by radioimmunoassay. As expected, oestradiol, but not oil, triggered a surge of LHRH in hypophysial portal blood with a peak at about 16.00 h of presumptive pro-oestrus. This oestradiol-induced surge of LHRH was blocked by ketanserin, ritanserin and the highly selective 5-HT2A receptor antagonist, RP62203, but not by fluoxetine. These results provide the first direct evidence that the 5-HT2A receptor plays an important role in the oestradiol-induced surge of LHRH.


Assuntos
Estradiol/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Receptores de Serotonina/fisiologia , Anestesia , Anestésicos , Animais , Óxidos S-Cíclicos/farmacologia , Diestro , Feminino , Fluoxetina/farmacologia , Hormônio Liberador de Gonadotropina/sangue , Ketanserina/farmacologia , Naftalenos/farmacologia , Ovariectomia , Hipófise/irrigação sanguínea , Pregnanodionas , Proestro , Ratos , Ratos Wistar , Receptor 5-HT2A de Serotonina , Ritanserina/farmacologia , Antagonistas da Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia
16.
J Appl Physiol (1985) ; 85(3): 1160-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9729595

RESUMO

Exercise training induces coronary vascular adaptations. The goal of this study was to contrast the effects of training on capillary and arteriolar growth. Minipigs were trained for 1, 3, 8, and 16 wk and compared with controls. Maximal O2 consumption increased continuously throughout the study. Capillary and arteriolar densities and diameters, and proliferation of vascular cells in these vessels, were determined in perfusion-fixed tissue. The arterioles were subdivided into five groups according to diameter: 10-19.9, 20-30, 31-40, 41-70, and 71-120 microgram. The total vascular bed cross-sectional area increased by 37% at 16 wk, mainly because of an increase in the number of the small arterioles and an increase in the diameter of the larger vessels. Capillary density increased at 3 wk and then returned to control levels by 16 wk; concomitantly, the number of arterioles (20-30 microgram) increased at 16 wk. We speculate that the "extra" capillaries observed at 3 wk were the source of the new arterioles.


Assuntos
Circulação Coronária/fisiologia , Neovascularização Fisiológica/fisiologia , Condicionamento Físico Animal/fisiologia , Animais , Arteríolas/fisiologia , Capilares/fisiologia , Permeabilidade Capilar/fisiologia , DNA/biossíntese , Masculino , Consumo de Oxigênio/fisiologia , Estresse Psicológico/fisiopatologia , Suínos , Porco Miniatura , Regulação para Cima/fisiologia
17.
Ann Thorac Surg ; 63(4): 1034-40, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9124901

RESUMO

BACKGROUND: Cardiomyoplasty (CMP) uses the latissimus dorsi muscle (LDM) to assist the heart in cases of cardiac failure. Distal ischemia and necrosis of the LDM is a recognized complication of CMP that can reduce distal muscle function and the mechanical effectiveness of CMP. METHODS: Canine (n = 9) LDMs were subjected to a 10-day period of vascular delay followed by a simulated CMP. Two weeks after simulated CMP (corresponding to the healing delay between CMP and the onset of LDM stimulation used in the clinical setting), LDM perfusion was measured in the distal, middle, and proximal segments of the muscle, and circumferential (distal and middle squeezing muscle function) and longitudinal (proximal pulling muscle function) force generation and fatigue rates were measured. The results were compared with the contralateral nondelayed simulated CMP. RESULTS: Muscle perfusion was significantly (p < 0.05) greater in the distal and middle segments of vascular-delayed LDMs. Circumferential muscle force generation and fatigue rates were significantly (p < 0.05) improved in the vascular-delayed LDMs. CONCLUSIONS: Vascular delay can significantly improve LDM perfusion and function in a model that closely reflects clinical CMP, and the use of vascular delay may improve clinical outcomes in CMP.


Assuntos
Cardiomioplastia/métodos , Músculo Esquelético/irrigação sanguínea , Animais , Cães , Estimulação Elétrica , Contração Muscular , Reoperação , Fatores de Tempo
18.
Brain Res ; 564(1): 27-30, 1991 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-1723340

RESUMO

Neuropeptides, including substance P (SP), calcitonin gene-related peptide (CGRP) and somatostatin (SS) in dorsal root ganglia (DRG) may play a role in neurogenic inflammation and pain transmission. Adrenal corticosteroids regulate neuropeptide synthesis in some areas of the CNS and may modulate neurogenic inflammation and sensory perception. We have investigated the effects of adrenalectomy and dexamethasone (0.2 mg/kg/day) treatment on neuropeptide content of rat cervical DRG using specific and sensitive radioimmunoassays. In control animals, a differential distribution of neuropeptide was found; SP and CGRP content increased from C4 to C7 in contrast to SS content, which decreased from C4 to C7. Ten days following adrenalectomy, the mean SS content of cervical DRG decreased significantly to 79.6 +/- 4.5% of sham-operated controls. In contrast, SP and CGRP content increased significantly 10 days after adrenalectomy to 134.6 +/- 6.9% and 132.0 +/- 11.6% of sham-operated controls, respectively. The effects of adrenalectomy on CGRP and SS were reversed by administration of dexamethasone. These results suggest that glucocorticoids affect the neuropeptide content of DRG in the adult rat.


Assuntos
Adrenalectomia , Dexametasona/farmacologia , Gânglios Espinais/metabolismo , Neuropeptídeos/metabolismo , Hormônio Adrenocorticotrópico/sangue , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Corticosterona/sangue , Gânglios Espinais/efeitos dos fármacos , Masculino , RNA Mensageiro/metabolismo , Radioimunoensaio , Ratos , Ratos Endogâmicos , Receptores de Glucocorticoides/biossíntese , Receptores de Glucocorticoides/efeitos dos fármacos , Somatostatina/metabolismo , Substância P/metabolismo
19.
Trans R Soc Trop Med Hyg ; 80(3): 406-11, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3798534

RESUMO

A model of human hookworm infection has been developed which shows that dogs currently infected with small numbers of hookworms are considerably resistant to a challenge infection with a large inoculum of infective larvae. Two groups of dogs were infected with 500 larvae and four weeks after infection one group together with a previously uninfected control group were infected with 5,000 larvae and followed for six weeks. When compared with the secondary infection control dogs, faecal egg excretion and adult worm burdens were reduced by an average of 83 and 78% respectively. Infections had no significant effect on total white cell counts, platelet levels or spontaneous, phytohaemagglutinin- and antigen-induced lymphocyte transformation among the three groups of dogs. Dogs previously uninfected with hookworm developed a marked anaemia when infected with 5,000 larvae but this was not observed in the superinfected group. An eosinophilia developed in all groups and there were no significant differences among the three groups of animals. Specific IgM antibodies developed transiently in all groups of dogs two weeks after infection. IgG antibody levels were significantly greater in the superinfected animals one, two and three weeks after challenge infection compared with the secondary infection control animals; by four weeks there was no significant difference between the two groups of animals. Both groups given the large inoculum of larvae developed specific IgA antibodies one week after the challenge infection and these continued to rise in the superinfected group until termination of the experiment. It is concluded that dogs currently infected with the hookworm, Ancylostoma ceylanicum, demonstrate the development of functional protective immunity.


Assuntos
Ancilostomíase/imunologia , Animais , Cães , Eosinófilos , Fezes/parasitologia , Hemoglobinas/análise , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Contagem de Leucócitos , Ativação Linfocitária , Masculino , Contagem de Ovos de Parasitas
20.
Trans R Soc Trop Med Hyg ; 79(4): 519-23, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4082263

RESUMO

A model of human hookworm infection has been developed which shows that dogs with chronic hookworm infection are considerably resistant to reinfection one month after the termination of the primary infection with anthelmintics. Challenge and control dogs were infected with 1,800 larvae and the infection was followed for six weeks. When compared with control dogs, faecal egg excretion and intestinal adult worm burdens in challenge dogs were reduced by 85% and 77%, respectively. Infection had no significant effect on haemoglobin concentrations, total white cell counts, platelet levels or spontaneous and phytohaemagglutinin-induced lymphocyte transformations in both control and previously infected dogs. Both groups of dogs developed an eosinophilia and lymphocytes responded transiently to stimulation with both larval and adult worm antigens, although there were no significant differences between the two groups of animals. Specific IgM antibodies were transient in both groups of animals following infection. Specific IgG antibodies were present at high levels before infection in challenge dogs when compared with control dogs, and fell transiently after challenge; three weeks after infection, IgG antibodies appeared in the control animals and titres continued to rise during the period of observation. Challenge dogs also developed specific IgA antibodies three weeks after infection, and these remained at high levels, but these antibodies were not detected in control dogs. Thus, dogs infected with this strain of the hookworm, Ancylostoma ceylanicum, which has been shown to infect man, develop functional protective immunity. These findings improve prospects for vaccine development.


Assuntos
Ancilostomíase/imunologia , Ancilostomíase/tratamento farmacológico , Ancilostomíase/parasitologia , Animais , Anti-Helmínticos/uso terapêutico , Modelos Animais de Doenças , Cães , Fezes/parasitologia , Imunidade Inata , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Ativação Linfocitária , Masculino , Contagem de Ovos de Parasitas , Fatores de Tempo
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