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1.
Handchir Mikrochir Plast Chir ; 48(6): 330-336, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27832668

RESUMO

Introduction: Autologous fat transfer has recently become an increasingly popular surgical procedure and comprises harvesting, processing and transplantation of adipose tissue, as well as professional follow-up care. This method, as a surgical procedure, can be utilised for trauma-, disease- or age-related soft tissue volume deficits and soft tissue augmentation. As usage is increasing, but the variables of fat harvest, specific indications and fashion of fat transfer are poorly defined, there is a great demand for development of a guideline in the field of reconstructive and aesthetic surgery. Methods: All relevant points were discussed within the scope of a consensus conference including a nominal group process of all societies involved in the procedure and ratified with a strong consensus (>95%). Literature from the standard medical databases over the last 10 years was retrieved, studied and specific guidelines were concluded. Results: Consensus was achieved among all professionals involved on the following points: 1. definition 2. indication/contraindication, 3. preoperative measures 4. donor sites 5. techniques of processing 6. transplantation 7. follow-up care 8. storage 9. efficacy 10. documentation 11. evaluation of patient safety. Conclusion: Definite indications and professional expertise are paramount for autologous fat tissue transfer. Successful transfers are based on the use of correct methods as well as specific instruments and materials. Autologous adipose tissue transplantation is considered to be a safe procedure in reconstructive and aesthetic surgery, due to the low rate of postoperative complications and sequelae.


Assuntos
Cirurgia Plástica , Transplante Autólogo , Tecido Adiposo , Consenso , Humanos , Procedimentos de Cirurgia Plástica
2.
Adipocyte ; 4(3): 181-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26257991

RESUMO

With adipose-derived stem cells being in the focus of research in regenerative medicine, the need arises for fast reliable cultivation protocols. We have tested the cultivation of human adipose-derived stem cells in endothelial cell growth medium prior to induction and differentiation, against the long-established use of DMEM/F12 medium-based cultivation protocols. We found that cultivation in endothelial cell growth medium not only accelerates growth before induction and differentiation, but also allows shorter induction and differentiation times than those following precultivation with DMEM/F12 medium with regard to the formation of mature adipocytes and to the viability undifferentiated cells. These results were first observed morphologically but could be confirmed by performing adiponectin ELISA and cell proliferation assays.

3.
Heredity (Edinb) ; 92(6): 534-42, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15162116

RESUMO

The major histocompatibility complex (MHC) has a central role in the specific immune defence of vertebrates. Exon 3 of MHC class I genes encodes the domain that binds and presents peptides from pathogens that trigger immune reactions. Here we develop a fast population screening method for detecting genetic variation in the MHC class I genes of birds. We found evidence of at least 15 exon 3 sequences in the investigated great reed warbler individual. The organisation of the great reed warbler MHC class I genes suggested that a locus-specific screening protocol is impractical due to the high similarity between alleles across loci, including the introns flanking exon 3. Therefore, we used motif-specific PCR to amplify two subsets of alleles (exon 3 sequences) that were separated with by DGGE. The motif-specific primers amplify a substantial proportion of the transcribed class I alleles (2-12 alleles per individual) from as many as six class I loci. Although not exhaustive, this gives a reliable estimate of the class I variation. The method is highly repeatable and more sensitive in detecting genetic variation than the RFLP method. The motif-specific primers also allow us to avoid screening pseudogenes. In our study population of great reed warblers, we found a high level of genetic variation in MHC class I, and no less than 234 DGGE genotypes were detected among 248 screened individuals.


Assuntos
Éxons/genética , Genes MHC Classe I/genética , Variação Genética/genética , Reação em Cadeia da Polimerase , Polimorfismo Genético , Aves Canoras/genética , Alelos , Animais , Primers do DNA , Feminino , Genética Populacional , Genótipo , Masculino , Filogenia
4.
Immunogenetics ; 53(4): 329-36, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11491536

RESUMO

We sequenced exon 2 of the MHC class II B gene in Atlantic salmon from the Baltic Sea and identified 17 different exon 2 alleles among 22 different restriction fragment length polymorphism haplotypes. The sequences differed at between 1 and 34 bases. Two different tests were used to estimate the importance of recombination in the generation of new alleles. Recombination events appear to have occurred between three and nine times. Only two pairs of sequences differed by less than five nucleotides, minimizing the importance of point mutations for generating new alleles. Phylogenetic analysis showed that sequences did not cluster according to populations, and genetic distances between populations were small compared to those obtained by allele frequency data. These results, together with the similarity found between exon 2 sequences from Baltic salmon and Norwegian salmon, indicate that all of the identified alleles were present in the ancient salmon population colonizing the Baltic rivers after the last glaciation.


Assuntos
Genes MHC da Classe II , Polimorfismo Genético , Salmo salar/genética , Alelos , Sequência de Aminoácidos , Animais , Oceano Atlântico , Sequência de Bases , Evolução Molecular , Variação Genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Recombinação Genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Suécia
5.
Proc Biol Sci ; 268(1466): 479-85, 2001 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-11296859

RESUMO

We have tested the importance of genetic variation in the major histocompatibility complex (MHC) class IIB in Atlantic salmon (Salmo salar) for survival after challenge with a highly virulent bacterial pathogen. Forty juvenile full siblings from each of 120 families were infected with the bacterium Aeromonas salmonicida, which causes high mortality in salmon due to furunculosis. Fishes from high-resistance (HR, < 35% mortality) and low-resistance (L,R, > 80% mortality) families were screened for their MHC class IIB genotypes using the denaturing gradient gel electrophoresis (DGGE) technique. The exon 2 sequences, encoding the major part of the peptide-binding region, were established for each DGGE fragment. One allele, e, containing a missense single base substitution was significantly more prevalent in HR families than in LR families. An odds-ratio test showed that broods carrying this allele had a 12-fold higher chance of being HR than broods without the e allele. A second allele, i, showed significantly higher frequencies in uninfected and surviving individuals than in infected dead individuals. A third allele, j, tended to more prevalent both in LR families and in individuals that had died of the infection. There was no correlation between MHC heterozygosity and resistance to A. salmonicida. Our results support the hypothesis that MHC polymorphism is maintained through pathogen-driven selection acting by means of frequency-dependent selection rather than heterozygous advantage.


Assuntos
Aeromonas/patogenicidade , Genes MHC da Classe II , Salmo salar/genética , Salmo salar/imunologia , Alelos , Animais , Sequência de Bases , DNA/genética , Éxons , Variação Genética , Dados de Sequência Molecular , Salmo salar/microbiologia
6.
J Biomed Mater Res ; 55(2): 203-16, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11255172

RESUMO

A number of different processing techniques have been developed to design and fabricate three-dimensional (3D) scaffolds for tissue-engineering applications. The imperfection of the current techniques has encouraged the use of a rapid prototyping technology known as fused deposition modeling (FDM). Our results show that FDM allows the design and fabrication of highly reproducible bioresorbable 3D scaffolds with a fully interconnected pore network. The mechanical properties and in vitro biocompatibility of polycaprolactone scaffolds with a porosity of 61 +/- 1% and two matrix architectures were studied. The honeycomb-like pores had a size falling within the range of 360 x 430 x 620 microm. The scaffolds with a 0/60/120 degrees lay-down pattern had a compressive stiffness and a 1% offset yield strength in air of 41.9 +/- 3.5 and 3.1 +/- 0.1 MPa, respectively, and a compressive stiffness and a 1% offset yield strength in simulated physiological conditions (a saline solution at 37 degrees C) of 29.4 +/- 4.0 and 2.3 +/- 0.2 MPa, respectively. In comparison, the scaffolds with a 0/72/144/36/108 degrees lay-down pattern had a compressive stiffness and a 1% offset yield strength in air of 20.2 +/- 1.7 and 2.4 +/- 0.1 MPa, respectively, and a compressive stiffness and a 1% offset yield strength in simulated physiological conditions (a saline solution at 37 degrees C) of 21.5 +/- 2.9 and 2.0 +/- 0.2 MPa, respectively. Statistical analysis confirmed that the five-angle scaffolds had significantly lower stiffness and 1% offset yield strengths under compression loading than those with a three-angle pattern under both testing conditions (p < or = 0.05). The obtained stress-strain curves for both scaffold architectures demonstrate the typical behavior of a honeycomb structure undergoing deformation. In vitro studies were conducted with primary human fibroblasts and periosteal cells. Light, environmental scanning electron, and confocal laser microscopy as well as immunohistochemistry showed cell proliferation and extracellular matrix production on the polycaprolactone surface in the 1st culturing week. Over a period of 3-4 weeks in a culture, the fully interconnected scaffold architecture was completely 3D-filled by cellular tissue. Our cell culture study shows that fibroblasts and osteoblast-like cells can proliferate, differentiate, and produce a cellular tissue in an entirely interconnected 3D polycaprolactone matrix.


Assuntos
Materiais Biocompatíveis , Engenharia Biomédica/métodos , Poliésteres , Fenômenos Biomecânicos , Divisão Celular , Células Cultivadas , Técnicas de Cultura , Fibroblastos/citologia , Técnica de Fratura por Congelamento , Humanos , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Modelos Teóricos , Osteoblastos/citologia , Propriedades de Superfície
7.
Immunogenetics ; 52(1-2): 92-100, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11132162

RESUMO

Humans express an array of Mhc genes, while the chicken has an Mhc that is relatively small and compact with fewer expressed genes. Here we ask whether the "minimal essential Mhc" of the chicken is representative for birds. We investigated the RFLP genotypes in 55 great reed warblers Acrocephalus arundinaceus and 10 willow warblers Phylloscopus trochilus to obtain an overview of the number of class II B genes. There were 13-17 bands per individual in the great reed warblers and 25-30 in the willow warblers, and every individual had a unique RFLP genotype. The high number of RFLP bands indicates that both species have a large number of class II B genes although some may be pseudogenes. Seven different class II B sequences were detected in a great reed warbler cDNA library. There was considerable sequence divergence between the cDNA sequences in exon 2 (peptide-binding region, PBR), whereas they were very similar in exon 3. The cDNA sequences were easily alignable to a classical chicken class II B sequence, and balancing selection was acting in the PBR. One of the cDNA sequences had two deletions and is likely nonfunctional. Finally, the polymorphic class I and class II B RFLP fragments seemed to be linked in the five studied great reed warbler families. These and previous results suggest that birds of the order Passeriformes in general have more Mhc class I and II B genes than birds of the order Galliformes. This difference could be caused by their phylogenetic past, and/or by variance in the selection pressure for maintaining a high number of Mhc genes.


Assuntos
Variação Genética , Complexo Principal de Histocompatibilidade , Aves Canoras/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , DNA Complementar , Dados de Sequência Molecular , Peptídeos/metabolismo , Polimorfismo de Fragmento de Restrição , Homologia de Sequência de Aminoácidos , Aves Canoras/imunologia
8.
Mol Ecol ; 9(10): 1529-38, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11050548

RESUMO

Genetic similarity within pairs of individuals was examined using both 10 polymorphic microsatellite loci and multi-locus DNA fingerprinting profiles in a semi-isolated population of great reed warblers at Lake Kvismaren, south Central Sweden, in 1987-1993. The population was founded by a few individuals in 1978, followed by a gradual increase in numbers until 1988, since when the population has remained relatively stable with about 60 breeding birds. We have previously found that high genetic similarity between pair-mates in the population during the early part of the study period reduced egg hatching success, and hence reproductive success. The measures of pairwise genetic similarity, microsatellite allele sharing and DNA fingerprinting band sharing, were highly correlated with pedigree-based relatedness. Both microsatellite and DNA fingerprinting similarities between pair-mates declined significantly over the study period, and the pattern was most pronounced in the DNA fingerprinting data. Analyses restricted to the microsatellite data showed that the average annual microsatellite similarity between pairwise combinations of individuals, as well as individual homozygosity in males, declined significantly over the study period, and that several immigrants carrying novel alleles entered the population during the study. Hence, the temporal decline in genetic similarity of mates in the population is probably a consequence of increased immigration, facilitated by the recent expansion of the species in the region. These results suggest that the population has now recovered genetically, or is in the process of recovering, from a recent founder event.


Assuntos
Genética Populacional , Repetições de Microssatélites , Aves Canoras/genética , Animais , Impressões Digitais de DNA , Feminino , Efeito Fundador , Variação Genética , Heterozigoto , Estudos Longitudinais , Masculino , Dados de Sequência Molecular , Linhagem , Suécia
9.
Int J Cancer ; 89(3): 251-8, 2000 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-10861501

RESUMO

Human gliomas express TGF-beta but, so far the expression of downstream mediators has been investigated in only a few cell lines. We have examined tissue specimens of 23 gliomas: 3 astrocytomas grade II (AST), 8 anaplastic astrocytomas grade III (AAST), and 12 glioblastoma multiforme grade IV (GBM). We analyzed the mRNA expression of TGF-beta1, TGF-beta2, TGF-beta3, the TGF-beta receptors type I (TbetaR-I) and type II (TbetaR-II), Smad2, Smad3, and Smad4. mRNA expression of IL-10 and CD95 (FAS/APO-1) were also studied. We detected increased mRNA levels of the 3 TGF-beta isoforms, correlating with the degree of malignancy. TGF-beta3 mRNA was increased, particularly in AST and AAST, while TGF-beta1 and TGF-beta2 mRNAs were strongly expressed in GBM. TGF-beta normally up-regulates the TGF-beta receptors, and TbetaR-I and TbetaR-II showed stronger expression in all gliomas when compared to normal tissues. However, the mRNA expression of Smad2, Smad3, and Smad4 was decreased in GBM. IL-10 mRNA expression was detected in glioma tissues but not in glioma cell lines. No marked increase in the expression of soluble CD95 splicing variants was found in the gliomas compared with normal tissue. However, total CD95 mRNA was elevated among GBM tissues.


Assuntos
Receptores de Ativinas Tipo I , Neoplasias Encefálicas/metabolismo , Proteínas de Ligação a DNA/biossíntese , Glioma/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Transativadores/biossíntese , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/química , Adolescente , Adulto , Astrocitoma/metabolismo , Encéfalo/metabolismo , DNA Complementar/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Glioblastoma/metabolismo , Humanos , Interleucina-10/biossíntese , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas , Proteínas Serina-Treonina Quinases/biossíntese , RNA Mensageiro/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Proteína Smad2 , Proteína Smad3 , Proteína Smad4 , Células Tumorais Cultivadas , Receptor fas/metabolismo
10.
Mol Ecol ; 9(2): 215-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10672165

RESUMO

We compared three different molecular methods currently used for screening of Mhc variation in population studies of Atlantic salmon. Restriction fragment length polymorphism (RFLP) of the entire class II gene detected 22 haplotypes. Seventeen exon 2 sequences were obtained from individuals carrying the 22 haplotypes, two of which had not been detected by RFLP. The six alleles (27%) detected by RFLP and not by exon 2 sequencing probably resulted from sequence variation outside exon 2. Within exon 2, RFLP differentiated 88% of the sequences. Alternatively, denaturing gradient gel electrophoresis (DGGE) performed under two run conditions detected 94% of the sequence variation. Both RFLP using different probes, and the two PCR-based methods using three different primer pairs, suggest that there is only a single Mhc class II B gene in the Baltic populations of Atlantic salmon.


Assuntos
Genes MHC da Classe II , Variação Genética , Polimorfismo de Fragmento de Restrição , Salmo salar/genética , Animais , Eletroforese em Gel de Poliacrilamida , Éxons , Haplótipos , Reação em Cadeia da Polimerase
11.
Proc Biol Sci ; 266(1414): 1-12, 1999 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-10081154

RESUMO

The immune and the detoxication systems of animals are characterized by allelic polymorphisms, which underlie individual differences in ability to combat assaults from pathogens and toxic compounds. Previous studies have shown that females may improve offspring survival by selecting mates on the basis of sexual ornaments and signals that honestly reveal health. In many cases the expression of these ornaments appears to be particularly sensitive to oxidative stress. Activated immune and detoxication systems often generate oxidative stress by an extensive production of reactive metabolites and free radicals. Given that tolerance or resistance to toxic compounds and pathogens can be inherited, female choice should promote the evolution of male ornaments that reliably reveal the status of the bearers' level of oxidative stress. Hence, oxidative stress may be one important agent linking the expression of sexual ornaments to genetic variation in fitness-related traits, thus promoting the evolution of female mate choice and male sexual ornamentation, a controversial issue in evolutionary biology ever since Darwin.


Assuntos
Variação Genética , Estresse Oxidativo , Comportamento Sexual Animal/fisiologia , Animais , Antioxidantes/metabolismo , Evolução Biológica , Biotransformação/genética , Feminino , Humanos , Imunidade/genética , Complexo Principal de Histocompatibilidade , Masculino
12.
Immunogenetics ; 49(3): 158-70, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9914330

RESUMO

The class I genes of the major histocompatibility complex (Mhc) are here investigated for the first time in a passerine bird. The great reed warbler is a rare species in Sweden with a few semi-isolated populations. Yet, we found extensive Mhc class I variation in the study population. The variable exon 3, corresponding to the alpha2 domain, was amplified from genomic DNA with degenerated primers. Seven different genomic class I sequences were detected in a single individual. One of the sequences had a deletion leading to a shift in the reading frame, indicating that it was not a functional gene. A randomly selected clone was used as a probe for restriction fragment length polymorphism (RFLP) studies in combination with the restriction enzyme Pvu II. The RFLP pattern was complex with 21-25 RFLP fragments per individual and extensive variation. Forty-nine RFLP genotypes were detected in 55 tested individuals. To study the number of transcribed genes, we isolated 14 Mhc class I clones from a cDNA library from a single individual. We found eight different sequences of four different lengths (1.3-2.2 kilobases), suggesting there are at least four transcribed loci. The number of nonsynonymous substitutions (dN) in the peptide binding region of exon 3 were higher than the number of synonymous substitutions (dS), indicating balancing selection in this region. The number of transcribed genes and the numerous RFLP fragments found so far suggest that the great reed warbler does not have a "minimal essential Mhc" as has been suggested for the chicken.


Assuntos
Expressão Gênica , Genes MHC Classe I/genética , Polimorfismo Genético , Aves Canoras/genética , Regiões 3' não Traduzidas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sondas de DNA , DNA Complementar/genética , Éxons/genética , Feminino , Biblioteca Gênica , Genoma , Antígenos HLA-A/química , Antígenos HLA-A/genética , Humanos , Fígado , Masculino , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Ligação Proteica , Alinhamento de Sequência , Aves Canoras/imunologia
13.
Cancer Epidemiol Biomarkers Prev ; 7(9): 809-12, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9752990

RESUMO

Human tumor and normal tissue specimens, which were collected from autopsy material 1-6 days postmortem, were compared with similar tissue specimens collected within 2 h after surgical resection and transport to the pathology department. The end point criteria used to evaluate the quality of the specimens for biological banking purposes were the extractability and yield of high molecular weight DNA and UV absorption ratios at 260:280 after collection and immediate storage of the specimens at -80 degrees C. The data demonstrated that autopsy material was a quality source of DNA, although of not such high quality as surgical biopsy specimens <2 h after resection. The advantages of using autopsy material to supplement surgical specimen collection sent to pathology, as opposed to using specimen collection at surgery wards or formalin-fixed material, as sources of DNA are: (a) large amounts of tumor and normal tissues from a variety of organ sites can be obtained without regard to the patient's health status; (b) a higher percentage of retrieval of incident cases of cancer in prospective designed trials is more likely to be achieved; and (c) the extractable DNA is of sufficiently high enough quality to permit direct analyses by molecular hybridization and sequence methodologies.


Assuntos
DNA de Neoplasias , Neoplasias , Bancos de Tecidos , Autopsia , DNA de Neoplasias/análise , Dieta , Estudos de Viabilidade , Humanos , Neoplasias/genética , Mudanças Depois da Morte , Manejo de Espécimes/métodos , Suécia , Bancos de Tecidos/organização & administração , Bancos de Tecidos/normas
14.
Genetica ; 104(3): 301-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10386396

RESUMO

The major histocompatibility complex (MHC) has been studied in a multitude of mammals by now, but much less is known about its organisation and variation in other vertebrate species. The mammalian MHC is organised as a single gene cluster, but recent studies on birds suggest that this paradigm of MHC organisation has to be supplemented. The domestic chicken thus possesses two separate gene clusters which both contain MHC class I and class II B genes, and we have shown that the ring-necked pheasant Phasianus colchicus also has two unlinked clusters of class II B genes. We are studying the effect of the MHC on mate choice, survival and reproductive success in natural populations of birds and reptiles. For this reason, we are developing DNA techniques to determine the animals' MHC genotype. The amplification of the hypervariable exon 3 of the class I gene from songbirds and reptiles has provided us with species specific probes that can be used in Southern blot analysis. The first results indicate very extensive variation in all studied species, that is starlings Sturnus vulgaris, great reed warblers Acrocephalus arundinaceus and water pythons Liasis fuscus. The restriction fragment length polymorphism (RFLP) analysis also suggests that the number of MHC genes is significantly larger in these species than in pheasants and domestic chickens.


Assuntos
Aves/genética , Aves/imunologia , Variação Genética , Complexo Principal de Histocompatibilidade , Répteis/genética , Répteis/imunologia , Animais , Animais Selvagens/genética , Animais Selvagens/imunologia , Boidae/genética , Boidae/imunologia , Galinhas/genética , Galinhas/imunologia , Sondas de DNA , Polimorfismo de Fragmento de Restrição , Aves Canoras/genética , Aves Canoras/imunologia , Especificidade da Espécie
15.
Proc Biol Sci ; 263(1368): 265-71, 1996 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-8920249

RESUMO

The major histocompatibility complex (MHC) is an immunologically important cluster of highly variable genes that is known to affect fitness in domesticated mammals and birds. Spur length of male pheasants in southern Sweden correlates with male viability, female mate choice, and offspring survival rate. Here we show by genetic analyses that the MHC genotype is associated with variation in both male spur length and male viability. These are the first data that directly support a 'good genes' hypothesis by Hamilton and Zuk predicting that females discriminate among males on the basis of secondary sexual characters in order to pass on genes for disease resistance that improve fitness in their offspring.


Assuntos
Complexo Principal de Histocompatibilidade , Modelos Genéticos , Caracteres Sexuais , Animais , Aves/anatomia & histologia , Aves/genética , Aves/imunologia , Feminino , Variação Genética , Genótipo , Masculino
17.
Immunogenetics ; 39(6): 395-403, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7910588

RESUMO

We investigated the class II B genes in a free-ranging population of the ring-necked pheasant Phasianus colchicus by a combination of restriction fragment length polymorphism (RFLP), polymerase chain reaction (PCR), and DNA sequencing. Special attention was paid to the variation in the second exon, which encodes the peptide-binding beta 1-domain. The population was introduced, but it still exhibited major histocompatibility complex polymorphism with at least three segregating class II B haplotypes and consequently six genotypes. We found two class II B genes associated with each haplotype. The class II B genes of birds had until then only been molecularly characterized in the domestic chicken. The pheasant genes were highly variable, although one of the amplified sequences was found in two different haplotypes. Taken together, the most polymorphic positions (residues 37 and 38) were not identical in any of the predicted protein sequences, but all except one of the motifs had already been found in the domestic chicken. Structurally important features in mammalian class II B genes were generally conserved also in the pheasant sequences, but the loss of a potential salt bridge constituent (Arg72) in several sequences may suggest a slightly different structure of the adjacent parts of the peptide-binding groove. The pheasant genes are most closely related to the so called B-LBII family in the chicken, indicating that this represents a major line of development among avian class II B genes.


Assuntos
Aves/genética , Genes MHC da Classe II/genética , Variação Genética/genética , Haplótipos/genética , Sequência de Aminoácidos , Animais , Animais Selvagens , Sequência de Bases , Éxons/genética , Genótipo , Íntrons/genética , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Suécia
18.
Nature ; 337(6203): 166-9, 1989 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-2911350

RESUMO

Recent theory on sexual selection suggests that females in species without paternal care choose mates by their secondary sexual characters because these indicate genotypic quality which will be transmitted to the offspring. These ideas are not yet empirically supported as data quantifying the relationship between female mate choice and female reproductive success are lacking. Only in one case, in Colias butterflies, has it been demonstrated unequivocally that females choose 'good genotypes' as mates and there is only one study, on Drosophila, demonstrating that mate choice increases one component of offspring fitness. Spur length of male pheasants (Phasianus colchicus) correlates with various fitness-related properties. We here present the first experimental field data showing that female pheasants select mates on the basis of male spur length and that female mate choice correlates with female reproductive success.


Assuntos
Aves/fisiologia , Seleção Genética , Comportamento Sexual Animal , Animais , Feminino , Masculino , Caracteres Sexuais
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