RESUMO
BACKGROUND: Phosphorylation of serine 118 (ser118) has been reported to be involved in the activation of estrogen receptor (ER). In the present study, we evaluated whether endocrine therapy modulated ER phosphorylation on ser118. PATIENTS AND METHODS: We carried out a tissue microarray that included 80 primary breast tumors obtained before the administration of endocrine therapy. A second tissue microarray included 52 tumors obtained after endocrine therapy from the same patients. Immunostainings were carried out for ER, Pser118ER, Her2, insulin growth factor receptor (IGFR), p21-activated kinase 1 (PAK1), pMAPK, bcl2 and progesterone receptor. RESULTS: Pser118ER staining was higher in Her2- (P = 0.06), IGFR- (P = 0.0002) and pMAPK-expressing tumors (P = 0.001). The level of ER phosphorylation was not different according to the occurrence of clinical tumor response (P = 0.16). Pser118ER expression was significantly reduced by endocrine therapy. The mean Pser118ER score was 163 [standard deviation (SD) 81] before endocrine therapy and 80 (SD 90) after endocrine therapy (P = 0.0001, paired t-test). The magnitude of Pser118ER decrease was higher in tumors that responded to endocrine therapy (mean decrease 128, SD 86) as compared with refractory tumors (mean decrease 38, SD 130) (P = 0.017, t-test). CONCLUSION: These findings suggest that endocrine therapy modulates ER on ser118. Pser118ER immunostaining could be used as surrogate marker to monitor treatment efficacy.
Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Adenocarcinoma/patologia , Idoso , Inibidores da Aromatase/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Receptor IGF Tipo 1/metabolismo , Serina/metabolismo , Tamoxifeno/uso terapêuticoRESUMO
Beetle 'horns' are rigid outgrowths of the insect cuticle used as weapons in contests for access to mates. Relative to their body size, beetle horns can be enormous. They protrude from any of five different regions of the head or thorax; they are curved, straight, branched or bladed; and their development is often coupled with the nutrient environment (male dimorphism) or with sex (sexual dimorphism). Here, we show that this extraordinary diversity of horns can be distilled down to four trajectories of morphological change--horn location, shape, allometry and dimorphism--and we illustrate how the developmental mechanisms regulating horn growth could generate each of these types of horn evolution. Specifically, we review two developmental pathways known to regulate growth of morphological structures in Drosophila and other insects: a limb-patterning pathway that specifies the location and shape of a structure, and the insulin pathway, which modulates trait growth in response to larval nutrition. We summarize preliminary evidence indicating that these pathways are associated with the development of beetle horns, and we show how subtle changes in the relative activities of these two pathways would be sufficient to generate most of the extant diversity of horn forms. Our objective is to intuitively connect genotype with phenotype, and to advocate an informed 'candidate gene' approach to studies of the developmental basis of evolution. We end by using this insight from development to offer a solution to the long-standing mystery of the scarabs: the observation by Darwin, Lameere, Arrow and others that this one family of beetles appeared to have a 'special tendency' towards the evolution of horns.
Assuntos
Padronização Corporal , Besouros/anatomia & histologia , Besouros/crescimento & desenvolvimento , Extremidades/crescimento & desenvolvimento , Cornos/crescimento & desenvolvimento , Insulina/metabolismo , Animais , Evolução Biológica , Besouros/classificação , Filogenia , Caracteres Sexuais , Transdução de SinaisRESUMO
Asexual reproduction could offer up to a two-fold fitness advantage over sexual reproduction, yet higher organisms usually reproduce sexually. Even in facultatively parthenogenetic species, where both sexual and asexual reproduction is sometimes possible, asexual reproduction is rare. Thus, the debate over the evolution of sex has focused on ecological and mutation-elimination advantages of sex. An alternative explanation for the predominance of sex is that it is difficult for an organism to accomplish asexual reproduction once sexual reproduction has evolved. Difficulty in returning to asexuality could reflect developmental or genetic constraints. Here, we investigate the role of genetic factors in limiting asexual reproduction in Nauphoeta cinerea, an African cockroach with facultative parthenogenesis that nearly always reproduces sexually. We show that when N. cinerea females do reproduce asexually, offspring are genetically identical to their mothers. However, asexual reproduction is limited to a nonrandom subset of the genotypes in the population. Only females that have a high level of heterozygosity are capable of parthenogenetic reproduction and there is a strong familial influence on the ability to reproduce parthenogenetically. Although the mechanism by which genetic variation facilitates asexual reproduction is unknown, we suggest that heterosis may facilitate the switch from producing haploid meiotic eggs to diploid, essentially mitotic, eggs.
RESUMO
An important transition in insect life-history evolution was the shift from a solitary existence to living in groups comprising specialized castes. Caste-forming species produce some individuals that reproduce and others with worker functions that have few or no offspring. Morphologically specialized castes are well known in eusocial species like ants and termites, but castes have also evolved in less-studied groups like thrips, aphids and polyembryonic wasps. Because selection acts at both the individual and the colony level, ratios of investment in different castes are predicted to vary with environmental factors like competition and resources. However, experimental evidence for adaptive shifts in caste ratios is limited owing to the experimental difficulty of manipulating factors thought to influence caste ratios, and because some species produce behaviourally flexible castes that switch tasks in response to colony needs. Unlike other caste-forming species, the broods of polyembryonic wasps develop clonally, so that increased production of one caste probably results in decreased production of the other. Here we show that the polyembryonic wasp Copidosoma floridanum alters caste ratios in response to interspecific competition. Our results reveal a distinct trade-off by C. floridanum between reproduction and defence, and show experimentally that caste ratios shift in an adaptive manner.
Assuntos
Adaptação Fisiológica , Comportamento Competitivo/fisiologia , Vespas/fisiologia , Animais , Feminino , Larva , Masculino , Mariposas/parasitologia , Reprodução , Comportamento Social , Especificidade da EspécieRESUMO
Understanding the phylogenetic relationships of the three major urochordate groups within the deuterostomes is central to understanding the evolution of the chordates. We have prepared a detailed phylogenetic analysis of urochordates based on comparisons of 10 new urochordate 18S ribosomal DNA sequences with other urochordate sequences in GenBank. Maximum parsimony, neighbor-joining, minimum evolution, and maximum likelihood analyses of this large urochordate data set are consistent with a topology in which the urochordates are monophyletic within the deuterostomes and there are four separate clades of urochordates. These four distinct clades--styelid + pyurid ascidians, molgulid ascidians, phlebobranch ascidians + thaliaceans, and larvaceans--are mostly consistent with traditional morphological hypotheses and classifications. However, we find that the ascidians may not be a monophyletic group (as they have been considered traditionally) but instead appear paraphyletic. Another disparity with traditional classification is that the thaliaceans do not form a separate urochordate clade but rather cluster with the phlebobranch ascidians. Larvaceans have long branch lengths, which can be problematic for molecular phylogenetic methods, and their position within the urochordates cannot be unequivocally determined with 18S rDNA. This is important because the tadpole morphology of larvacean and ascidian larvae is the key trait of interest that distinguishes urochordates as chordates. Nevertheless, the present data set resolves at least three clades of urochordates and suggests strongly that urochordates form a monophyletic clade within the deuterostomes.
Assuntos
DNA/genética , Urocordados/classificação , Animais , Filogenia , Urocordados/genéticaRESUMO
Considerable work in evolutionary biology has focused on the question of why sex persists. Both advantages to sex and constraints limiting a return to asexual reproduction are hypothesized to maintain sex once it evolves. Developmental constraints would limit asexual reproduction from a sexual species if it were difficult for females to switch from making eggs that do not develop without fertilization to making zygotes that are capable of developing in the absence of fertilization. Nauphoeta cinerea is an ovoviviparous cockroach in which some females are capable of switching from a sexual mode of reproduction to an asexual mode when isolated from males. Yet, while facultative parthenogenesis can occur in individuals, few females make the switch. Thus, this cockroach provides an ideal system for examining the potential role of developmental constraints in maintaining sex. Here we compare the cytogenetics and embryonic development of sexual and parthenogenetic offspring in N. cinerea. We find that deviations from normal ploidy levels are associated with abnormal development. All viable N. cinerea embryos exhibit typically hemimetabolous insect embryogenesis. Although there is no variation among embryos in development within a sexually produced clutch, we see extreme variation in asexually derived clutches. These results suggest that developmental constraints limit the success of asexual reproduction in this facultatively parthenogenetic cockroach. Our data further suggest that the specific constraint occurs in the switch from a meiotic mode of reproduction requiring fertilization to diploid zygotes that develop in the absence of fertilization.
Assuntos
Baratas/fisiologia , Partenogênese , Reprodução , Animais , Baratas/embriologia , Baratas/crescimento & desenvolvimento , Desenvolvimento Embrionário , Feminino , Imuno-Histoquímica , MasculinoRESUMO
Animals have evolved diverse appendages adapted for locomotion, feeding and other functions. The genetics underlying appendage formation are best understood in insects and vertebrates. The expression of the Distal-less (Dll) homeoprotein during arthropod limb outgrowth and of Dll orthologs (Dlx) in fish fin and tetrapod limb buds led us to examine whether expression of this regulatory gene may be a general feature of appendage formation in protostomes and deuterostomes. We find that Dll is expressed along the proximodistal axis of developing polychaete annelid parapodia, onychophoran lobopodia, ascidian ampullae, and even echinoderm tube feet. Dll/Dlx expression in such diverse appendages in these six coelomate phyla could be convergent, but this would have required the independent co-option of Dll/Dlx several times in evolution. It appears more likely that ectodermal Dll/Dlx expression along proximodistal axes originated once in a common ancestor and has been used subsequently to pattern body wall outgrowths in a variety of organisms. We suggest that this pre-Cambrian ancestor of most protostomes and the deuterostomes possessed elements of the genetic machinery for and may have even borne appendages.
Assuntos
Evolução Biológica , Proteínas de Homeodomínio/biossíntese , Invertebrados/anatomia & histologia , Vertebrados/anatomia & histologia , Sequência de Aminoácidos , Animais , Anelídeos , Drosophila , Ingestão de Alimentos , Equinodermos , Extremidades , Peixes , Variação Genética , Proteínas de Homeodomínio/química , Insetos/anatomia & histologia , Insetos/classificação , Invertebrados/classificação , Botões de Extremidades , Camundongos , Dados de Sequência Molecular , Movimento , Nematoides , Filogenia , Homologia de Sequência de Aminoácidos , Vertebrados/classificaçãoRESUMO
The clinical, radiographic, and pathologic features were studied in 24 cases of bronchiolitis obliterans and 16 cases of usual interstitial pneumonia, to define better their distinguishing characteristics. Bronchiolitis obliterans had a more acute onset often associated with fever, while the presentation of usual interstitial pneumonia was insidious with dyspnea and cough. The radiographs in usual interstitial pneumonia uniformly showed bilateral interstitial opacities, while they were more variable in bronchiolitis obliterans, with air space densities in 15 and interstitial opacities in nine. Prognosis was considerably better for bronchiolitis obliterans patients. Resolution of disease occurred in nearly half, while no patient with usual interstitial pneumonia recovered. Three individuals with bronchiolitis obliterans (12.5%) died of progressive disease, compared to 10 with usual interstitial pneumonia (62.5%). Pathologically, the lesion in bronchiolitis obliterans affected mainly air spaces in a peribronchiolar distribution, while the changes in usual interstitial pneumonia were mainly interstitial and randomly distributed. The fibrosis in bronchiolitis obliterans was composed of proliferating fibroblasts, compared to collagen deposition in usual interstitial pneumonia. These findings emphasize that bronchiolitis obliterans and usual interstitial pneumonia represent separate and distinct clinicopathologic entities.
Assuntos
Bronquite/patologia , Fibrose Pulmonar/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibrose Pulmonar/classificação , Fibrose Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/fisiopatologia , Radiografia Torácica , Testes de Função RespiratóriaAssuntos
Brônquios , Broncoscopia , Corpos Estranhos/diagnóstico por imagem , Idoso , Broncografia , Corpos Estranhos/terapia , Humanos , MasculinoRESUMO
K. pneumoniae capsule type 68 infused into the uterus of 4 mares was recovered up to 15 weeks after inoculation. The insertion of a tampon for 10 min was more effective than a swab technique in detecting the organism in the uterus. The clitoral fossa and the urethral orifice when sampled by the swab technique were also found to be infected for a comparable period. K. pneumoniae was isolated from the clitoral specimens more often and more consistently than from either urethral or uterine specimens.
Assuntos
Doenças dos Genitais Femininos/veterinária , Doenças dos Cavalos/diagnóstico , Infecções por Klebsiella/veterinária , Klebsiella pneumoniae/isolamento & purificação , Animais , Técnicas Bacteriológicas , Feminino , Doenças dos Genitais Femininos/microbiologia , Doenças dos Cavalos/microbiologia , Cavalos , Infecções por Klebsiella/diagnósticoRESUMO
Human lymphoblastoid interferon was produced on an 800-liter scale (2.6 X 10(9) units) by induction of Namalva cells with Newcastle disease virus, strain B1. The interferon was partially purified by anti-leukocyte interferon affinity chromatography, sulfopropyl Sephadex ion exchange chromatography, isoelectric focusing, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Recovery of interferon after gel electrophoresis varied from 11 to 33% based on the original crude material, with about 35,000-fold purification. The gel electrophoresis resolved the antiviral activity into two components with apparent molecular weights of 18,000 and 22,000; treatment with glycosidases resulted in all the activity being associated with the lower molecular weight species. Interferon activity could be completely (85 to 113%) recovered from the gels by elution into a buffer containing sodium dodecyl sulfate. The presence of sodium dodecyl sulfate did not appear to affect the assay of interferon. The protein could also be completely (75 to 106%) eluted from gels stained with coomassie blue, again with no loss in activity.
Assuntos
Interferons/isolamento & purificação , Linhagem Celular , Cromatografia de Afinidade , Humanos , Focalização Isoelétrica , Métodos , Vírus da Doença de NewcastleRESUMO
The effect of colostrum on transepithelial migration of live Escherichia coli 055:B5:H7 in the neonatal calf intestine was determined by microbiological and microscopic investigations. Colostrum-deprived calves (2 to 6 h old) were given E. coli suspended in saline, E. coli suspended in colostrum, or E. coli in saline 1 h after colostrum. Twenty-four hours after exposure, tissues were collected for examination. Escherichia coli were numerous in mesenteric lymph nodes of calves given this organism in saline. Fewer were recovered from nodes of calves that received the bacteria in colostrum. Escherichia coli were not recovered from mesenteric lymph nodes of calves given colostrum before dosage with the organism. Electron microscopic studies of small intestines from calves that received E. coli in saline revealed bacterial attachment sites surrounded by exfoliation of microvilli. Bacteria appeared to enter epithelial cells by invagination of apical plasma membrane or dilation of apical tubules. Intracellular E. coli were enclosed in a surrounding membrane. The organisms were not observed adhering to or penetrating intestinal epithelium of calves that received E. coli in colostrum or 1 h after colostrum.
Assuntos
Colostro , Escherichia coli , Intestino Delgado/microbiologia , Animais , Bovinos , Colostro/fisiologia , Epitélio/microbiologia , Epitélio/fisiologia , Epitélio/ultraestrutura , Íleo/ultraestrutura , Mucosa Intestinal/microbiologia , Mucosa Intestinal/fisiologia , Intestino Delgado/fisiologia , Masculino , PermeabilidadeRESUMO
Calves received either colostrum with 2.83 meq potassium isobutyrate per gram of gamma-globulin or colostrum with distilled water within 1 h after birth. Blood samples were taken at intervals during the first 72 h for determination of concentrations of gamma-globulin, immunoglobulin IgG and IgM. Calves fed colostrum with distilled water attained higher concentrations in serum of total gamma-globulin, immunolgobulin IgG and IgM. Holstein calves were more efficient than Ayrshire calves in absorbing total gamma-globulin, but differences between breeds were not significant for specific immunoglobulins. Efficiency of gamma-globulin absorption within 24 h was 35.7% for control calves and 24.7% for calves fed colostrum plus potassium isobutyrate. Potassium isobutyrate had a depressing effect on absorption of immunoglobulins by calves.
Assuntos
Animais Recém-Nascidos/metabolismo , Butiratos/farmacologia , Bovinos/metabolismo , Colostro/imunologia , Imunoglobulinas/metabolismo , Absorção Intestinal , Potássio/farmacologia , Animais , Animais Recém-Nascidos/imunologia , Bovinos/imunologia , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , gama-Globulinas/análiseRESUMO
Human leukocyte and tritium-labeled fibroblast interferons, prepared by induction with Sendai virus and with double-stranded polyinosinic acid.polycytidylic acid respectively, have been studied in relation to the carbohydrate moieties attached to them. These interferons were partially purified by immunoabsorbance and by gel filtration. On treatment with glycosidases, about 80% of the 3H-labeled sugar moieties in this glycoprotein-containing fraction was removed without detectable alteration of the antiviral activity or antibody-binding properties characteristic of interferon. The molecular weight of leukocyte interferon was reduced by about 4000. As others have reported, the heterogeneous character of interferon revealed by isoelectric focusing was greatly reduced by the enzyme treatment.
Assuntos
Carboidratos/análise , Fibroblastos/metabolismo , Glicosídeo Hidrolases , Humanos , Focalização Isoelétrica , Leucócitos/metabolismo , Peso Molecular , Vírus da Parainfluenza 1 HumanaRESUMO
Human interferon prepared by challenge of leukocytes with Sendai virus, or of fibroblasts with double-stranded poly(inosinic acid).poly(cytidylic acid), has been studied with respect to purification by affinity chromatography. Both leukocyte and fibroblast interferons are removed from crude tissue culture fluids by means of columns of antibody to leukocyte interferon attached to Sepharose-4B. The antibody was prepared in sheep using, as antigen, material that had been partially purified by gel filtration through Sephadex G-100 columns. Many of the impurities in the crude fibroblast interferon were presumably not recognized by the sheep antibodies induced by leukocyte interferon. Fibroblast interferon was, therefore, much more effectively purified as the result of this "common denominator" approach. The fibroblast product, in contrast to interferon from leukocytes, could only be harvested efficiently from the crude starting material when a carrier protein (bovine-serum albumin, and later, cytochrome c) was added to the eluting buffers to counteract losses, presumably due to adsorption on purification and assay equipment. Both varieties of interferon exhibit molecular weights of approximately 20,000-25,000, although association with higher molecular weight proteins occurs.