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1.
Lupus ; 24(9): 900-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25595621

RESUMO

OBJECTIVES: Historically, arthroplasty in systemic lupus erythematosus (SLE) patients has been less successful than for patients with osteoarthritis (OA). It is not known if SLE remains an independent risk factor for poor arthroplasty outcomes or if other factors, such as avascular necrosis (AVN), continue to play a role. METHODS: A case-control study using data from a single-institution arthroplasty registry compared SLE total hip arthroplasty (THA) and total knee arthroplasty (TKA) with OA controls matched by age, gender and presence of AVN. Baseline, two-year administrative and self-report data, and diagnosis leading to arthroplasty were evaluated. RESULTS: A total of 54 primary SLE THA and 45 primary SLE TKA were identified from May 2007 through June 2011. AVN was present in 32% of SLE THA and no TKA. SLE THA had worse preoperative WOMAC pain (42.5 vs. 52.7; p = 0.01) and function (38.8 vs. 48.0; p = 0.05) compared with OA. However, at two years there was no difference in WOMAC pain (91.1 vs. 92.1; p = 0.77) or WOMAC function (86.4 vs. 90.8; p = 0.28). SLE TKA were similar to OA in both preoperative pain (42.6 vs. 48.4; p = 0.14) and function (42.1 vs. 46.8; p = 0.30) and two-year pain (85.7 vs. 88.6; p = 0.50) and function (83.7 vs. 85.1; p = 0.23). Compared to OA, SLE THA and TKA patients had more renal failure (14% vs. 1%; p = 0.007) and hypertension (52% vs. 29%; p = 0.009). In a multivariate linear regression, SLE was not predictive of either poor pain or poor function. CONCLUSIONS: While SLE patients have more comorbidities than OA, and SLE THA have worse preoperative pain and function compared with OA controls, SLE was not an independent risk factor for poor short-term pain or function after either hip or knee arthroplasty.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Lúpus Eritematoso Sistêmico/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteonecrose/fisiopatologia , Estudos Prospectivos , Qualidade de Vida , Fatores de Risco , Resultado do Tratamento
2.
Mol Ecol ; 23(16): 4153-67, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24975563

RESUMO

Studies focusing on geographical genetic patterns of commensal species and on human history complement each other and provide proxies to trace common colonization events. On Madagascar, the unintentional introduction and spread of the commensal species Rattus rattus by people may have left a living clue of human colonization patterns and history. In this study, we addressed this question by characterizing the genetic structure of natural populations of R. rattus using both microsatellites and mitochondrial sequences, on an extensive sampling across the island. Such data sets were analysed by a combination of methods using population genetics, phylogeography and approximate Bayesian computation. Our results indicated two introduction events to Madagascar from the same ancestral source of R. rattus, one in the extreme north of the island and the other further south. The latter was the source of a large spatial expansion, which may have initially started from an original point located on the southern coast. The inferred timing of introduction events-several centuries ago-is temporally congruent with the Arabian trade network in the Indian Ocean, which was flourishing from the middle of the first millennium.


Assuntos
Evolução Molecular , Genética Populacional , Ratos/genética , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Ilhas , Madagáscar , Repetições de Microssatélites , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNA
3.
J Evol Biol ; 26(5): 1019-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23621368

RESUMO

The Loky-Manambato region, located in northern Madagascar, is a biotically rich contact zone between different forest biomes. Local current forest cover is composed of both humid and dry formations, which show elevational stratification. A recent phylogeographical study of a regional dry forest rodent, Eliurus carletoni (subfamily Nesomyinae), found genetic evidence of forest contractions between 18 750 and 7500 years BP, which based on extrapolation of the pollen subfossil record, was thought to be associated with an expansion of local humid forests. Herein, we conduct a genetic test of this hypothesis and focused on populations on two neighbouring massifs of forest-dependent rodent species, one associated with low-elevation dry forests (E. carletoni) and the other with higher elevation humid forests (Eliurus tanala). Using mitochondrial markers and a combination of traditional and coalescent-based phylogeographical, historical demographic and population genetic methods, we found evidence of historical connections between populations of E. tanala. Adjacent populations of E. carletoni and E. tanala exhibit opposite historical demographic patterns, and for both, evidence suggests that historical demographic events occurred within the last 25 000 years BP. These findings strongly support the proposed late Quaternary shifts in the floristic composition of the Loky-Manambato region.


Assuntos
Ecossistema , Roedores/genética , Animais , Evolução Biológica , Feminino , Variação Genética , Madagáscar , Filogeografia
4.
Parasite ; 18(2): 127-40, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21678788

RESUMO

The Hippoboscidae or "louse-flies" is a family of pupiparous Diptera, which in their adult stage are ectoparasites of mammals and birds. This paper presents a comprehensive review of Malagasy Hippoboscidae. In total, amongst the 213 species of this family known worldwide, 14 have been reported in Madagascar, among which six are considered as endemic to the Malagasy region. In addition, data are presented from a collection of 17 Hippoboscidae obtained from seven species of forest-dwelling birds in the "Parc National de Midongy Befotaka", southeastern Madagascar, in 2003. The flies in this collection belong to three different species: Icosta malagasii (one), Ornithoica podicipis (ten) and Ornithoctona laticomis (six). The two former species were previously only known from single specimens in museum collections; the later species is distributed across much of the Afrotropical region and the records presented herein are the first for Madagascar. All the seven bird species are new hosts for hippoboscids. We present the first description of the male of Icosta malagasii. An illustrated dichotomous determination key of the 14 Malagasy species, based on morphological criteria only, is presented.


Assuntos
Doenças das Aves/parasitologia , Dípteros/classificação , Ectoparasitoses/veterinária , Mamíferos/parasitologia , Animais , Aves , Dípteros/anatomia & histologia , Ectoparasitoses/parasitologia , Feminino , Madagáscar , Masculino , Asas de Animais/anatomia & histologia
5.
J Evol Biol ; 24(6): 1298-306, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21443643

RESUMO

Eocene ocean currents and prevailing winds correlate with over-water dispersals of terrestrial mammals from Africa to Madagascar. Since the Early Miocene (about 23 Ma), these currents flowed in the reverse direction, from the Indian Ocean towards Africa. The Comoro Islands are equidistant between Africa and Madagascar and support an endemic land vertebrate fauna that shares recent ancestry predominantly with Madagascar. We examined whether gene flow in two Miniopterus bat species endemic to the Comoros and Madagascar correlates with the direction of current winds, using uni- and bi-parentally inherited markers with different evolutionary rates. Coalescence-based analyses of mitochondrial matrilines support a Pleistocene (approximately 180,000 years ago) colonization event from Madagascar west to the Comoros (distance: 300 km) in the predicted direction. However, nuclear microsatellites show that more recent gene flow is restricted to a few individuals flying against the wind, from Grande Comore to Anjouan (distance: 80 km).


Assuntos
Migração Animal , Quirópteros/fisiologia , Fluxo Gênico , Vento , Asas de Animais/fisiologia , Animais , DNA Mitocondrial/química , Voo Animal , Geografia , Repetições de Microssatélites , Alinhamento de Sequência , Análise de Sequência de DNA
6.
J Morphol ; 271(12): 1493-500, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20927800

RESUMO

The morphology of the spermatozoon of representative species of the subfamily Nesomyinae (Muroidea: Nesomyidae), a monophyletic group of rodents endemic to Madagascar, was examined by light and electron microscopy to determine the sperm head shape and tail length across the species. Marked interspecific differences were found to occur in both the form of the sperm head and length of the tail. The species that possess a sperm head with an apical hook, which largely contains acrosomal material, generally displayed longer sperm tails, and a species with a spatulate sperm head had the shortest tail. The association between sperm head shape and tail length mirrors that previously found in Eurasian and Australasian murine rodents. Thus, the repeated association between sperm head shape and tail length across these groups of muroid rodents clearly indicates a functional relationship between these two features. A comparison of sperm morphology of the nesomyines to that of related muroid rodents on the mainland of Africa suggests that the possession of an apical hook is the ancestral condition.


Assuntos
Roedores/anatomia & histologia , Cabeça do Espermatozoide/ultraestrutura , Cauda do Espermatozoide/ultraestrutura , Animais , Madagáscar , Masculino
7.
Placenta ; 29(6): 484-91, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18374977

RESUMO

The reproductive tract was examined in four non-pregnant and two gravid specimens of Myzopoda. The ovaries had little interstitial tissue. The uterus was bicornuate and the lenticular placental disk was situated mesometrially in one horn. The interhaemal barrier of the placental labyrinth was of the endotheliomonochorial type. There was a single layer of trophoblast cells. The cells of the maternal endothelium were large and basophilic, contained abundant rough endoplasmic reticulum, and rested on an irregular basement membrane. Blunt projections of endometrium extended into the placental disk and clusters of large cells occurred between the endometrial stroma and labyrinth. At the margins of the disk folds of trophoblast occurred and at the cranial end they formed an haemophagous region. The folds lateral to the disk included some peculiar tubular-appearing structures. There was a persistent yolk sac containing large endodermal cells around a largely collapsed lumen. Several features of placentation, such as the interhaemal barrier and the haemophagous region, are consistent with an association of Myzopodidae with Emballonuridae. No support was found for alternative hypotheses that include Myzopodidae in the noctilionoid or vespertilionoid lineages.


Assuntos
Quirópteros/fisiologia , Genitália Feminina/fisiologia , Placentação/fisiologia , Prenhez , Animais , Feminino , Genitália Feminina/anatomia & histologia , Madagáscar , Placenta/anatomia & histologia , Placenta/citologia , Gravidez
8.
Chromosome Res ; 15(8): 1075-91, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18058249

RESUMO

Tenrecs (Tenrecidae) are a widely diversified assemblage of small eutherian mammals that occur in Madagascar and Western and Central Africa. With the exception of a few early karyotypic descriptions based on conventional staining, nothing is known about the chromosomal evolution of this family. We present a detailed analysis of G-banded and molecularly defined chromosomes based on fluorescence in situ hybridization (FISH) that allows a comprehensive comparison between the karyotypes of 11 species of two closely related Malagasy genera, Microgale (10 species) and Oryzorictes (one species), of the subfamily Oryzorictinae. The karyotypes of Microgale taiva and M. parvula (2n = 32) were found to be identical to that of O. hova (2n = 32) most likely reflecting the ancestral karyotypes of both genera, as well as that of the Oryzorictinae. Parsimony analysis of chromosomal rearrangements that could have arisen following Whole Arm Reciprocal Translocations (WARTs) showed, however, that these are more likely to be the result of Robertsonian translocations. A single most parsimonious tree was obtained that provides strong support for three species associations within Microgale, all of which are consistent with previous molecular and morphological investigations. By expanding on a recently published molecular clock for the Tenrecidae we were able to place our findings in a temporal framework that shows strong chromosomal rate heterogeneity within the Oryzorictinae. We use these data to critically examine the possible role of chromosomal rearrangements in speciation within Microgale.


Assuntos
Cromossomos de Mamíferos/genética , Eulipotyphla/classificação , Eulipotyphla/genética , Animais , Bandeamento Cromossômico , Coloração Cromossômica , Hibridização in Situ Fluorescente , Cariotipagem , Madagáscar , Translocação Genética
9.
Mol Ecol ; 16(4): 839-51, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17284215

RESUMO

New applications of genetic data to questions of historical biogeography have revolutionized our understanding of how organisms have come to occupy their present distributions. Phylogenetic methods in combination with divergence time estimation can reveal biogeographical centres of origin, differentiate between hypotheses of vicariance and dispersal, and reveal the directionality of dispersal events. Despite their power, however, phylogenetic methods can sometimes yield patterns that are compatible with multiple, equally well-supported biogeographical hypotheses. In such cases, additional approaches must be integrated to differentiate among conflicting dispersal hypotheses. Here, we use a synthetic approach that draws upon the analytical strengths of coalescent and population genetic methods to augment phylogenetic analyses in order to assess the biogeographical history of Madagascar's Triaenops bats (Chiroptera: Hipposideridae). Phylogenetic analyses of mitochondrial DNA sequence data for Malagasy and east African Triaenops reveal a pattern that equally supports two competing hypotheses. While the phylogeny cannot determine whether Africa or Madagascar was the centre of origin for the species investigated, it serves as the essential backbone for the application of coalescent and population genetic methods. From the application of these methods, we conclude that a hypothesis of two independent but unidirectional dispersal events from Africa to Madagascar is best supported by the data.


Assuntos
Quirópteros/genética , Demografia , Evolução Molecular , Genética Populacional , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Primers do DNA , Geografia , Madagáscar , Modelos Genéticos , Dados de Sequência Molecular , Dinâmica Populacional , Análise de Sequência de DNA
10.
Placenta ; 28(7): 748-59, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17113148

RESUMO

Placentation in tenrecs of the subfamily Oryzorictinae, family Tenrecidae, has not been described previously. The structure of the placenta of this group and especially of the genus Microgale was investigated to determine its similarity or dissimilarity to previously described placentas of the tenrec subfamilies Potamogalinae and Tenrecinae. Fifteen specimens of the genus Microgale ranging from an early yolk sac stage to near term were available for study. Placentation in Microgale was found to be different from other tenrecids in that there is an early simple lateral rather than central haemophagous region. In addition, a more villous portion of the placental disk forms before the formation of a more compact labyrinth. Although the definitive placenta is cellular haemomonochorial, it lacks the spongy zone found in the Tenrecinae. Neither does it resemble the endotheliochorial condition found in the Potamogalinae. Of the two genera of the subfamily Oryzorictinae represented by single specimens, the placenta of Limnogale resembled that of the Microgale but Oryzorictes had several differences including a lobulated placental disk. It is concluded that there is more variation in placentation both within the subfamily Oryzorictinae and within the family Tenrecidae than would ordinarily be expected.


Assuntos
Eulipotyphla/fisiologia , Placentação , Musaranhos/fisiologia , Animais , Eulipotyphla/anatomia & histologia , Feminino , Masculino , Placenta/citologia , Gravidez , Musaranhos/anatomia & histologia
11.
Arch Inst Pasteur Madagascar ; 69(1-2): 70-6, 2003.
Artigo em Francês | MEDLINE | ID: mdl-15678820

RESUMO

This study aims to evaluate the prevalence and density of haemoparasites in wild malagasy bats. Among the 440 bats, belonging to 14 species sampled in 5 localities in different bio-climatic zones of the island, 93 (21%) showed at least 1 haemoparasite with, by order of frequency, Haemoproteidae (15.7% of 440 bats), microfilariae (7.0%) and Trypanosoma (0.7%). Among these 93 bats, 92 (99%) belonged to the family Vespertilionidae. Four bat species, all endemic to the Madagascar region (Madagascar and Comoros), were found to harbour parasites: Miniopterus manavi with Haemoproteidae (38% of 129 individuals), microfilariae (23%) and Trypanosoma (2%); Myotis goudoti with Haemoproteidae (24% of 68 individuals) and microfilariae (1%); Miniopterus gleni with Haemoproteidae (23% of 13 individuals); and Triaenops furculus with Haemoproteidae (4% of 28 individuals). The sex of bats was not linked to parasite prevalence. Within Miniopterus manavi, those individuals with greater weight also had a higher prevalence of microfilariae; and within the individuals harbouring microfilariae the greatest weights corresponded to the highest density of microfilariae. Ten bat species (with 202 individuals examined) were negative for any haemoparasite. This study is the first to provide evidence of haemoparasites in Malagasy bats; it provides interesting insights, especially concerning the parasite distribution per bat species and families, the pathogenicity of this type of parasitism and the parasite transmission by arthropod vectors.


Assuntos
Quirópteros/parasitologia , Doenças Parasitárias em Animais/sangue , Doenças Parasitárias em Animais/epidemiologia , Altitude , Animais , Vetores Artrópodes/parasitologia , Peso Corporal , Quirópteros/classificação , Quirópteros/fisiologia , Clima , Doenças Endêmicas/estatística & dados numéricos , Feminino , Filariose/epidemiologia , Humanos , Madagáscar/epidemiologia , Masculino , Microfilárias/parasitologia , Doenças Parasitárias em Animais/parasitologia , Doenças Parasitárias em Animais/transmissão , Densidade Demográfica , Vigilância da População , Prevalência , Distribuição por Sexo , Tripanossomíase/epidemiologia
12.
Arch Inst Pasteur Madagascar ; 68(1-2): 90-9, 2002.
Artigo em Francês | MEDLINE | ID: mdl-12643101

RESUMO

This study aims to evaluate the prevalence and density of haemoparasites in native Malagasy birds. Among the 387 birds, belonging to 43 species sampled at six localities in different bio-climatic zones of the island, 139 (35.9%) showed at least 1 hemoparasite with, by order of frequency, Plasmodium and/or Haemoproteus (19.9%), microfilariae (13.7% of 387 birds), Leucocytozoon (11.1%) and Trypanosoma (1.0%). An analysis to further elucidate these observations took into account the interaction of different environmental variables (altitude, season, site of collection) or aspects of the birds (age, weight, sex). There is evidence that some parasites preferentially infect some bird species or families. The largest male birds harboured the highest prevalences and densities of haemoparasite, regardless of species. These findings extend knowledge of bird/blood parasite relationships of Malagasy birds and provide interesting insights, especially concerning the pathogenicity of this type of parasitism and the parasite transmission by insect vectors.


Assuntos
Animais Selvagens/parasitologia , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Doenças Parasitárias em Animais/sangue , Doenças Parasitárias em Animais/epidemiologia , Distribuição por Idade , Altitude , Animais , Doenças das Aves/parasitologia , Peso Corporal , Clima , Helmintíase Animal/sangue , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Madagáscar/epidemiologia , Malária/sangue , Malária/epidemiologia , Malária/parasitologia , Malária/veterinária , Masculino , Doenças Parasitárias em Animais/parasitologia , Vigilância da População , Prevalência , Estações do Ano , Distribuição por Sexo , Tripanossomíase/sangue , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia , Tripanossomíase/veterinária
13.
Arch Inst Pasteur Madagascar ; 67(1-2): 49-52, 2001.
Artigo em Francês | MEDLINE | ID: mdl-12471749

RESUMO

Ticks are traditionally considered being host-specific parasites. The pattern of tick-host relationship was elucidated by exhaustive collection from a considerable number of potential hosts from numerous sites in the Malagasy mid-altitude forest. It can from the findings be concluded that the Malagasy ticks found on small mammals may be distinguished as either having a broad host-specificity or being highly host-specific. The results may provide important information in respect to phylogenetic studies with regards to the geological history of Madagascar and its endemic fauna.


Assuntos
Vetores Aracnídeos/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Ixodes/fisiologia , Controle de Ácaros e Carrapatos/métodos , Altitude , Animais , Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/parasitologia , Doenças Endêmicas/estatística & dados numéricos , Ixodes/microbiologia , Ixodes/parasitologia , Madagáscar , Mamíferos/fisiologia , Filogenia , Vigilância da População , Estudos de Amostragem , Especificidade da Espécie
14.
Proc Natl Acad Sci U S A ; 97(21): 11325-30, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11005834

RESUMO

Phylogenetic analysis of mtDNA sequence data confirms the observation that species diversity in the world's smallest living primate (genus Microcebus) has been greatly underestimated. The description of three species new to science, and the resurrection of two others from synonymy, has been justified on morphological grounds and is supported by evidence of reproductive isolation in sympatry. This taxonomic revision doubles the number of recognized mouse lemur species. The molecular data and phylogenetic analyses presented here verify the revision and add a historical framework for understanding mouse lemur species diversity. Phylogenetic analysis revises established hypotheses of ecogeographic constraint for the maintenance of species boundaries in these endemic Malagasy primates. Mouse lemur clades also show conspicuous patterns of regional endemism, thereby emphasizing the threat of local deforestation to Madagascar's unique biodiversity.


Assuntos
DNA Mitocondrial/genética , Lemur/genética , Animais , Haplótipos , Lemur/classificação , Camundongos , Dados de Sequência Molecular , Filogenia , Especificidade da Espécie
15.
Lupus ; 9(5): 318-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10878721

RESUMO

Systemic lupus erythematosus is reported to affect the lungs in almost half of patients, but pleuritis is most commonly encountered. Acute pneumonitis is an uncommon but recognized manifestation of SLE. Infection and drug reactions are more frequently diagnosed. The case discussed below permits consideration of the dilemmas typical of the SLE patient who presents with an acute pulmonary process.


Assuntos
Febre/etiologia , Lúpus Eritematoso Sistêmico/complicações , Pneumonia/etiologia , Feminino , Febre/fisiopatologia , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/fisiopatologia , Pessoa de Meia-Idade , Pneumonia/diagnóstico por imagem , Pneumonia/fisiopatologia , Radiografia , Esteroides/uso terapêutico
16.
Mol Phylogenet Evol ; 14(3): 436-44, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10712848

RESUMO

The avian family Cuculidae (cuckoos) is a diverse group of birds that vary considerably in behaviors of interest to behavioral ecologists, e.g., obligate brood parasitism and cooperative breeding. The taxonomy of this group has historically been relatively stable but has not been extensively evaluated using molecular methods. The goal of this study was to evaluate phylogenetic relationships within the ecologically diverse genus Coua and the placement of Coua among major cuckoo lineages. We sequenced 429 bp of cytochrome b (cyt b) and 522 bp of ND2, both mitochondrial genes, for 26 species of cuckoos spanning 13 genera. We also included the enigmatic hoatzin (Opisthocomus hoazin) and used two Tauraco species as outgroups. ND2 exhibited higher rates of DNA sequence and amino acid substitution than cyt b; however, this did not greatly affect the overall levels of phylogenetic resolution and support provided by these two genes. Combined analyses produced two alternative phylogenies, depending on weighting scheme, both of which were fully resolved and were characterized by high bootstrap support. These phylogenies recovered monophyly for all of the traditional cuckoo subfamilies and indicated, with strong support, that the hoatzin is outside of Cuculidae. Within Coua, an arboreal and a terrestrial clade were identified. In contrast, habitat choice of Coua species did not greatly reflect the phylogeny.


Assuntos
Grupo dos Citocromos b/genética , NADH Desidrogenase/genética , Aves Canoras/classificação , Aves Canoras/genética , Animais , DNA Mitocondrial/genética , Evolução Molecular , Variação Genética , Filogenia , Análise de Sequência de DNA
19.
Brain Res Mol Brain Res ; 18(1-2): 87-99, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8479293

RESUMO

The amino acid sequence of mouse brain beta spectrin (beta fodrin), deduced from the nucleotide sequence of complementary DNA clones, reveals that this non-erythroid beta spectrin comprises 2363 residues, with a molecular weight of 274,449 Da. Brain beta spectrin contains three structural domains and we suggest the position of several functional domains including f-actin, synapsin I, ankyrin and spectrin self association sites. Analysis of deduced amino acid sequences indicated striking homology and similar structural characteristics of brain beta spectrin repeats beta 11 and beta 12 to globins. In vitro analysis has demonstrated that heme is capable of specific attachment to brain spectrin, suggesting possible new functions in electron transfer, oxygen binding, nitric oxide binding or heme scavenging.


Assuntos
Proteínas de Transporte/genética , Proteínas dos Microfilamentos/genética , Proteínas do Tecido Nervoso/genética , Espectrina/genética , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Química Encefálica , Proteínas de Transporte/metabolismo , Sequência Consenso , DNA/genética , Globinas/genética , Hemina/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteínas dos Microfilamentos/metabolismo , Dados de Sequência Molecular , Família Multigênica , Proteínas do Tecido Nervoso/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Espectrina/metabolismo
20.
Radiology ; 181(2): 355-7, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1924771

RESUMO

The discomfort that patients experience during mammography is probably related to a variety of factors, one of which might be the amount of compression used. The authors measured the amount of force applied to the breasts during mammography and the resulting breast thickness in 560 women and correlated these measurements with the patient's subjective impression of the examination. The amount of force applied ranged from 49 to 186.2 N (median, 122.5 N). Breast thickness ranged from 10 to 88 mm (median, 46.5 mm). Forty-seven women (8%) rated the examination as painful (ie, mammography was either "very uncomfortable" or "intolerable"). Logistic regression analysis revealed a highly significant relationship between probability of a painful response and ratio of force to thickness (P = .007). Current guidelines suggest that maximum available force be at least 160 N but not more than 200 N. However, because increasing force is associated with increasing likelihood of pain, technologists should be aware that these recommended maximum limits are not intended to be used routinely for all women. In this study, high-quality mammograms were obtained in a majority of women with forces less than the maximum available level.


Assuntos
Mamografia , Mama/anatomia & histologia , Feminino , Humanos , Mamografia/efeitos adversos , Mamografia/métodos , Ciclo Menstrual , Dor/etiologia , Pressão
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