RESUMO
Patients with rheumatoid arthritis (RA) have increased oxidative stress, decreased antioxidant levels, and impaired antioxidant capacity. Cold treatments are used to relieve joint inflammation and pain. Therefore, we measured the effect of cold treatments on the antioxidative capacity of RA patients with active disease. Sixty patients were randomized to (1) whole body cryotherapy at -110 °C, (2) whole body cryotherapy at -60 °C, or (3) local cryotherapy. Each treatment was given three times daily for 7 consecutive days in addition to the conventional rehabilitation. Blinded rheumatologist evaluated disease activity before the first and after the last cryotherapy. We collected plasma samples daily immediately before the first and after the second cryotherapy and measured total peroxyl radical trapping antioxidant capacity of plasma (TRAP), which reflects global combined antioxidant capacity of all individual antioxidants in plasma. Baseline morning TRAP levels (mean, 95% CI), adjusted for age, body mass index, disease activity, and dose of prednisolone, were 1244 (1098-1391) µM/l in the local cryotherapy, 1133 (1022-1245) µM/l in the cryotherapy at -60 °C, and 989 (895-1082) µM/l in the cryotherapy at -110 °C groups (p = 0.006). After the first treatment, there was a rise in 1-h TRAP of 14.2 (-4.2 to 32.6) µM/l, 16.1 (-7.4 to 39.6) µM/l, and 23.6 (4.1-43.2) µM/l, respectively. The increase was significant in the whole-body cryotherapy -110 °C group (p < 0.001) but not significant between the groups (p = 0.78). When analyzed for the whole week, the daily morning TRAP values differed significantly between the treatment groups (p = 0.021), but there was no significant change within each treatment group. Whole-body cryotherapy at -110 °C induced a short-term increase in TRAP during the first treatment session with but not during other treatment modalities. The effect was short and the cold treatments did not cause a significant oxidative stress or adaptation during 1 week.
Assuntos
Antioxidantes/metabolismo , Artrite Reumatoide/terapia , Autoanticorpos/sangue , Crioterapia/métodos , Adulto , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Biomarcadores/sangue , Crioterapia/efeitos adversos , Feminino , Finlândia , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Testes Sorológicos , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: Acute stress in patients with rheumatoid arthritis (RA) should stimulate a strong stress response. After cryotherapy, we expected to observe an increase of hormones of the adrenal gland and the sympathetic nervous system. METHODS: A total of 55 patients with RA were recruited for whole-body cryotherapy at -110 degrees C and -60 degrees C, and local cold therapy between -20 degrees C and -30 degrees C for 7 days. We measured plasma levels of steroid hormones, neuropeptide Y (sympathetic marker), and interleukin (IL)6 daily before and after cryotherapy. RESULTS: In both therapy groups with/without glucocorticoids (GC), hormone and IL6 levels at baseline and 5 h after cold stress did not change over 7 days of cryotherapy. In patients without GC, plasma levels of cortisol and androstenedione were highest after -110 degrees C cold stress followed by -60 degrees C or local cold stress. The opposite was found in patients under GC therapy, in whom, unexpectedly, -110 degrees C cold stress elicited the smallest responses. In patients without GC, adrenal cortisol production increased relative to other adrenal steroids, and again the opposite was seen under GC therapy with a loss of cortisol and an increase of dehydroepiandrosterone. Importantly, there was no sympathetic stress response in both groups. Patients without GC and -110 degrees C cold stress demonstrated higher plasma IL6 compared to the other treatment groups (not observed under GC), but they showed the best clinical response. CONCLUSIONS: We detected an inadequate stress response in patients with GC. It is further shown that the sympathetic stress response was inadequate in patients with/without GC. Paradoxically, plasma levels of IL6 increased under strong cold stress in patients without GC. These findings confirm dysfunctional stress axes in RA.
Assuntos
Artrite Reumatoide/imunologia , Crioterapia/métodos , Interleucina-6/sangue , Estresse Fisiológico , Androstenodiona/sangue , Artrite Reumatoide/sangue , Artrite Reumatoide/terapia , Biomarcadores/sangue , Desidroepiandrosterona/sangue , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Neuropeptídeo Y/sangue , Estatísticas não ParamétricasRESUMO
OBJECTIVE: Local cryotherapy is used to relieve pain and inflammation in injuries and inflammatory conditions. Whole-body cryotherapy is an extreme method administered at -110 degrees C for 2 to 3 minutes. The aim of the study was to compare the effect of cryotherapies on pain and inflammation in patients with rheumatoid arthritis (RA). METHODS: Sixty patients with active seropositive RA were recruited in a randomised controlled single-blinded study to receive whole-body cryotherapy at -110 degrees C, whole-body cryotherapy at -60 degrees C, application of local cold air at -30 degrees C and the use of cold packs locally. In the final analysis, the last 2 groups were pooled. The patients had 2-3 cryotherapy sessions daily for one week plus conventional physiotherapy. Clinical and laboratory variables and patient's and physician's global assessments were used to assess the outcome. Disease activity was calculated by DAS. RESULTS: Pain decreased in all treatment groups, most markedly in the whole-body cryotherapy (-110 degrees C) group. DAS decreased slightly with no statistically significant differences between the groups. No serious or permanent adverse effects were detected. Six of 40 patients (15%) discontinued the whole-body cryotherapy. CONCLUSION: Pain seemed to decrease more in patients in the whole-body cryotherapy at -110 degrees C than during other cryotherapies, but there were no significant differences in the disease activity between the groups. However, cryotherapy at -110 degrees C is expensive and available only in special centres and may have minor adverse effects. Based on our results, whole-body cryotherapy at -110 degrees C is not superior to local cryotherapy commonly used in RA patients for pain relief and as an adjunct to physiotherapy.
Assuntos
Artrite Reumatoide/terapia , Crioterapia/métodos , Manejo da Dor , Adulto , Idoso , Artrite Reumatoide/fisiopatologia , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Dor/fisiopatologia , Medição da Dor , Índice de Gravidade de Doença , Método Simples-Cego , Temperatura , Resultado do TratamentoRESUMO
Animals with determinate growth have shown little variation in individual growth patterns, but similar analyses for animals with indeterminate growth have been lacking. We analysed the amount of phenotypic variation in growth patterns across ages among individuals of a hatchery-based population of Arctic charr, Salvelinus alpinus, Salmonidae, using the infinite-dimensional model and including the effects of group size structure. There was little phenotypic variation in growth trajectories: individuals that were small (in relation to the mean) early in life were among the smallest 2.5 years later. If the genetic variation reflects phenotypic variation, not much evolutionary change can be expected. Our results show that there are ecological conditions that determine the strong covariation of size across ages, most likely size-related dominance behaviour, which can mask the true variation of growth patterns. Thus, social interactions can have strong evolutionary effects on traits not directly involved in the behavioural interactions.
Assuntos
Adaptação Fisiológica , Comportamento Social , Truta/genética , Fatores Etários , Animais , Constituição Corporal , Ecologia , Feminino , Masculino , FenótipoRESUMO
Paclitaxel is currently formulated in a vehicle of 50% ethanol and 50% polyethoxylated surfactant cremophor EL. Cremophor EL has been reported to reverse P-glycoprotein-mediated multidrug resistance (MDR) at doses which are clinically achievable. It has also been reported to have a cytotoxic effect per se. In this study we used two different methods to evaluate the survival of cells exposed to paclitaxel with or without cremophor EL and the vehicle alone. Two laryngeal SCC cell lines (UT-SCC-19A and UT-SCC-29) and two ovarian adenocarcinoma cell lines (UT-OC-3 and UT-OC-5) established in our laboratory were investigated. Northern hybridisation was used to study the mdr-1 mRNA expression of the cell lines. With sensitive Northern analyses, these four lines yielded mdr-1 mRNA signals of the expected 4.5 kb size and of variable intensity, generally at higher levels than those in the positive control cell line KB. The 96-well plate clonogenic assay was used to obtain the fraction survival data and apoptosis was recorded by time-lapse video microscopy. Both methods indicate that cremophor EL alone has no effect on cellular survival. Consequently, paclitaxel without cremophor EL is as active as paclitaxel with cremophor EL in vitro.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Glicerol/análogos & derivados , Paclitaxel/farmacologia , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma de Células Escamosas/patologia , Sobrevivência Celular/efeitos dos fármacos , Glicerol/administração & dosagem , Glicerol/farmacologia , Humanos , Paclitaxel/administração & dosagem , Veículos Farmacêuticos , Células Tumorais Cultivadas/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco/métodosAssuntos
Trabalho de Parto/fisiologia , Trabalho de Parto/psicologia , Acontecimentos que Mudam a Vida , Mães/psicologia , Feminino , Sofrimento Fetal/etiologia , Humanos , Recém-Nascido , Complicações do Trabalho de Parto/psicologia , Satisfação do Paciente , Gravidez , Estresse Psicológico/complicaçõesRESUMO
In social foraging, scroungers take a disproportionately large share of the food found relative to their own food-searching efforts, while producers find more food than they manage to monopolize. We present a model of social foraging acknowledging the finder's advantage and foraging role asymmetries among individuals but incorporating the possibility that producers and scroungers differ in vigilance level and in vulnerability to predators. This allows simultaneous examination of both foraging benefits and anti-predatory aspects of grouping behaviour. Instead of seeking for equal payoff conditions, we first look for groups in which foraging character combinations and anti-predatory properties of producers and scroungers minimize the phenotype-specific predation hazard over food-intake rate, Ri/Ii, that is, fixed phenotype Ri/Ii minima. In the second approach, we allow individuals to change their foraging status to achieve lower Ri/Ii and look for combinations where it no longer pays for either producers or scroungers to change their roles, that is, evolutionarily stable group compositions, ESS. Various character combinations allow the phenotype-specific minima. In most cases, however, producers' and scroungers' minima are achievable only in different group compositions. The ESS combinations of producers and scroungers deviate widely from those combinations yielding phenotype-specific minima of Ri/Ii. If individuals are allowed to be flexible in adopting either a producer or a scrounger role, ESS group compositions will emerge, even though they are more expensive for both producers and scroungers in terms of Ri/Ii than group compositions yielding the phenotype-specific Ri/Ii minima. Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.
RESUMO
Mutations of the NF1 tumor suppressor gene cause type 1 neurofibromatosis, characterized by multiple tumors of the peripheral nerves, as well as other tumor types. The NF1 protein, neurofibromin, is intricately linked to the cell growth regulatory signalling pathways, e.g. by possessing RAS-GTPase activity. The regulation and role of neurofibromin are not known in normal human development. We addressed this issue by studying the regulation of neurofibromin in normal human peripheral nerves, from early fetal development to adulthood. The barely detectable neurofibromin immunosignal in peripheral nerves during the first trimester of gestation contrasted dramatically to its increase in Schwann cells, perineurial cells, and axons during the second and third trimesters. Interestingly, the type I and II isoforms of neurofibromin, differing in their RAS oncoprotein inactivation capacity, displayed clearly different expression profiles throughout these periods. This suggests distinct cellular functions for these neurofibromin isoforms. The results also revealed distinct species-specific differences in neurofibromin expression, potentially bearing relevance to the lack of human neurofibromatosis-like disorders in other species.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Genes da Neurofibromatose 1 , Nervo Isquiático/metabolismo , Adulto , Células Cultivadas , Desenvolvimento Embrionário e Fetal , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Proteínas do Tecido Nervoso/genética , Neurofibromina 1 , Neurônios/citologia , Neurônios/metabolismo , Proteínas/análise , Proteínas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Schwann/citologia , Células de Schwann/metabolismo , Nervo Isquiático/citologia , Nervo Isquiático/embriologia , Transcrição GênicaRESUMO
Arteriovenous malformations (AVMs) are congenital lesions composed of abnormal vasculature, with no capillary component, and are clinically significant due to their tendency to spontaneously hemorrhage. The mechanisms regulating the genesis and progression of these lesions are unknown. In order to study the role of angiogenesis in AVMs, we have analyzed the expression of the endothelial cell mitogen vascular endothelial growth factor (VEGF) and a novel endothelial cell-specific receptor tyrosine kinase, Tie, by in situ hybridization and immunohistochemistry in these malformations and surrounding brain tissue. We have previously shown upregulation of Tie accompanying wound healing and tumor progression. In this study, we demonstrate significantly elevated levels of Tie mRNA and protein in AVM and surrounding brain vasculature. Upregulation of VEGF mRNA was observed in the cells of brain parenchyma adjacent to the AVM, and VEGF protein was detected in this tissue as well as in AVM endothelia. Normal brain, in comparison, expressed little or no Tie or VEGF. The significant upregulation of VEGF and Tie in AVMs may indicate some ongoing angiogenesis, possibly contributing to the slow growth and maintenance of the AVM, and could be of potential use in the therapeutic targeting of these lesions.
Assuntos
Vasos Sanguíneos/metabolismo , Endotélio Vascular/metabolismo , Malformações Arteriovenosas Intracranianas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Regulação para Cima , Adulto , Antígenos Nucleares , Biomarcadores , Vasos Sanguíneos/patologia , Divisão Celular , Criança , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Endotélio Vascular/patologia , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/patologia , Linfocinas/genética , Linfocinas/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores de TIE , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
The expression of laminin alpha1, alpha2, beta1, beta2 and gamma1 subunits and proalpha1(I), proalpha1(III), alpha1(IV), alpha1(VI), alpha2(VI) and alpha3(VI) collagen chains was studied by Northern hybridizations, RNase protection assays and indirect immunofluorescence (IIF) labellings in cell cultures initiated from sciatic nerves of 14-27-wk-old human fetuses. The cultures represented mixed populations of Schwann cells, perineurial cells and fibroblasts, as estimated by morphology and S 100 protein immunolabellings. The mRNAs for certain basement membrane (BM) components, laminin beta1 and gamma1 chains and collagen alpha1(IV) chain, were readily detectable by Northern analyses in all cultures. In contrast, laminin alpha1, alpha2 and beta2 chain mRNAs were expressed at markedly lower levels. The expression of laminin alpha1 chain was detectable only by RNase protection assay. RNase protection analysis also demonstrated that the expression of laminin alpha2 chain increased with the developmental stage of the nerve used as the source for cell cultures. The expression of laminin beta2 chain was detected only at the protein level by IIF which demonstrated a faint immunosignal in a small subpopulation of cells. The mRNAs for type I, III and VI collagens were readily detectable in the cultures by Northern hybridizations. In summary, the extracellular matrix genes expressed in fetal human peripheral nerves and corresponding cell cultures display marked similarities. Cell cultures characterized here may prove useful in analyses elucidating potential roles of selected growth factors and cytokines in the induction of e.g. laminin alpha1 and beta2 chain expression by cells of developing peripheral nerves.
Assuntos
Colágeno/genética , Expressão Gênica , Laminina/genética , Nervo Isquiático/fisiologia , Adulto , Envelhecimento/fisiologia , Células Cultivadas , Desenvolvimento Embrionário e Fetal , Feto/metabolismo , Humanos , Masculino , Nervos Periféricos/citologia , Nervos Periféricos/embriologia , Nervos Periféricos/fisiologia , RNA Mensageiro/metabolismo , Células de Schwann/fisiologia , Nervo Isquiático/citologia , Nervo Isquiático/embriologiaRESUMO
We have previously characterized intrachromosomal rearrangements at 1p32 fusing the first exon of the RLF gene with L-myc. Here we present the full-length cDNA sequence of the 6251 bp RLF mRNA. The predicted 1914 amino acid Rlf protein contains sixteen widely spaced zinc finger motifs, and is related to the Zn-15 transcription factor. RLF is widely expressed in fetal and adult tissues, suggesting that it has a general role in transcriptional regulation. The zinc fingers are not contained in the 79 amino acid N-terminal region of RLF involved in the RLF-L-myc fusions, and the transforming ability of the RLF-L-myc and the normal L-myc proteins is indistinguishable. These findings suggest that the role of the rearrangements fusing RLF and L-myc is to deregulate the tightly controlled expression of the L-myc gene.
Assuntos
Proteínas de Ligação a DNA/genética , Rearranjo Gênico , Genes myc , Transativadores/genética , Fatores de Transcrição/genética , Dedos de Zinco , Adulto , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , Proteínas de Ligação a DNA/fisiologia , Fatores de Troca do Nucleotídeo Guanina , Humanos , Dados de Sequência Molecular , RNA Mensageiro/análise , Transativadores/fisiologiaRESUMO
The primary structure of the human laminin M chain was determined from cDNA clones isolated from human placental libraries. The clones covered a total of 6,942 bp, with 49-bp encoding a 5' end untranslated region and 6,893-bp coding for a translated sequence. The complete human laminin M chain contains a 22-residue signal peptide and 3,088 residues of the mature M chain. The M chain has a domain structure similar to that of the human and mouse A chains. The homology between the two human laminin heavy chains is highest in the short arm region and lowest in the long arm helical domain I + II. Northern blot analysis of human fetal tissues showed that the M chain was expressed in most tissues such as cardiac muscle, pancreas, lung, spleen, kidney, adrenal gland, skin, testis, meninges, choroid plexus, and some other regions of the brain, but not in liver, thymus, and bone. In situ hybridization localized the expression of the M chain gene to cells of mesenchymal origin. In contrast, expression of the A chain was observed only in kidney, testis, neuroretina and some region of brain as determined by Northern analyses. Epithelial and endothelial cells were negative for both M and A chain gene transcripts. The gene for the human M chain (LAMM) was localized to chromosome 6q22-->23.
Assuntos
Cromossomos Humanos Par 6 , Feto/metabolismo , Laminina/química , Laminina/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , DNA Complementar , Humanos , Hibridização In Situ , Laminina/biossíntese , Proteínas de Membrana/biossíntese , Proteínas de Membrana/química , Proteínas de Membrana/genética , Dados de Sequência Molecular , Especificidade de Órgãos , Sondas RNA , Alinhamento de SequênciaRESUMO
Deregulated expression of myc proto-oncogenes is implicated in several human neoplasias. We analysed the expression of c-myc, N-myc, L-myc, max and RB1 mRNAs in a panel of human gliomas and glioma cell lines and compared the findings with normal neural cells. The max and RB1 genes were included in the study because their protein products can interact with the Myc proteins, being thus putative modulators of Myc activity. Several gliomas contained c/L-myc mRNAs at levels higher than those in fetal brain, L-myc predominantly in grade II/III and c-myc in grade III gliomas. High-level N-myc expression was detected. In one small-cell glioblastoma and lower levels in five other gliomas. In contrast, glioma cell lines totally lacked N/L-myc expression. The in situ hybridisations revealed mutually exclusive topographic distribution of myc and glial fibrillary acidic protein (GFAP) mRNAs, and a lack of correlation between myc expression and proliferative activity, max and RB1 mRNAs were detected in most tumours and cell lines. The glioma cells displayed interesting alternative splicing patterns of max mRNAs encoding Max proteins which either suppress (Max) or augment (delta Max) the transforming activity of Myc. We conclude that (1) glioma cells in vivo may coexpress several myc genes, thus resembling fetal neural cells; but (2) cultured glioma cells expression only c-myc; (3) myc, max and RB1 are regulated independently in glioma cells; and (4) alternative processing of max mRNA in some glioma cells results in delta Max encoding mRNAs not seen in normal fetal brain.
Assuntos
Neoplasias Encefálicas/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes do Retinoblastoma/genética , Genes myc/genética , Glioma/genética , Fatores de Transcrição , Adulto , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Fatores de Transcrição de Zíper de Leucina Básica , Northern Blotting , Encéfalo/enzimologia , Encéfalo/fisiologia , Proteína Glial Fibrilar Ácida/genética , Humanos , Hibridização In Situ , Proteínas de Neurofilamentos/genética , Neurônios/fisiologia , RNA Mensageiro/genética , Ribonucleases/metabolismo , Células Tumorais Cultivadas , Vimentina/genéticaRESUMO
The myc proto-oncogenes encode nuclear DNA-binding phosphoproteins which regulate cell proliferation and differentiation. The c-myc gene is implicated in hematopoietic malignancies on the basis of its frequent deregulation in naturally occurring leukemias and lymphomas. Recent evidence suggests that also the N-myc and L-myc genes may have a role in normal and malignant hematopoiesis. N-myc and to a certain degree L-myc can substitute for c-myc in transformation assays in vitro, and their overexpression can block the differentiation of leukemia cell lines. Immunoglobulin heavy chain enhancer (IgH) -driven overexpression of N-myc or L-myc genes cause lymphatic and myeloid tumors, respectively, in transgenic mice. Furthermore, the L-myc and N-myc genes are expressed in several human leukemias and leukemia cell lines, L-myc predominantly in myeloid and N-myc both in myeloid and in some lymphoid leukemias. All N/L-myc positive leukemias and leukemia cell lines coexpress the c-myc gene, thus exemplifying a lack of negative cross-regulation between the different myc genes in leukemia cells. Taken together, these data suggest that L-myc and N-myc may participate in the growth regulation of hematopoietic cells.
Assuntos
Genes myc , Leucemia/genética , Linfoma/genética , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas c-myc/fisiologia , RNA Mensageiro/metabolismoRESUMO
Northern analyses, RNAase protection assays and in situ hybridizations were used to study the expression of the mRNA for the alpha 2 chain of collagen XI and the two different mRNAs generated from the collagen II gene through alternative splicing of exon 2 in several different tissues of 15-19-week-old fetuses. The highest expression levels of procollagen alpha 2(XI) and alpha 1(II) mRNAs were detected in cartilage, but, using long exposure times, Northern hybridization revealed the presence of the approximately 5.3 kb procollagen alpha 1(II) mRNA in most tissues analysed: calvarial and diaphyseal bone, striated and cardiac muscle, skin, brain, lung, kidney, liver, small intestine and colon. Both alternatively spliced forms of the mRNA were present in these tissues. In cartilage, the short form of the procollagen alpha 1(II) mRNA (without exon 2 sequences) was clearly more abundant, whereas in most of the non-cartilaginous tissues the long form was the predominant one. Low levels of procollagen alpha 2(XI) mRNA were also seen in non-cartilaginous tissues: calvarial and diaphyseal bone, kidney, skin, muscle, intestine, liver, brain, and lung. In all the other positive tissues except brain cortex, both collagen II and XI transcripts were observed. The localization of collagen II and XI signals was identical in cartilage, kidney and skin. However, in cartilage the signal with collagen II probe was much higher than that with the collagen alpha 2(XI) probe. In epidermis the situation was reversed. Our results show considerable co-expression and co-localization of procollagen alpha 1(II) and alpha 2(XI) mRNAs in many tissues of developing human fetuses. Since the collagen alpha 1(II) gene also codes for the alpha 3(XI) chain of collagen XI we propose that some, but not all, of the expression of the collagen II gene in non-cartilaginous tissues relates to collagen XI production.
Assuntos
Colágeno/genética , Éxons , Feto/metabolismo , Expressão Gênica , Splicing de RNA , Sequência de Bases , Northern Blotting , Southern Blotting , DNA/química , Sondas de DNA , Lâmina de Crescimento/embriologia , Lâmina de Crescimento/metabolismo , Humanos , Hibridização In Situ , Rim/química , Rim/embriologia , Dados de Sequência Molecular , Especificidade de Órgãos , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Ribonucleases , Pele/química , Pele/embriologiaRESUMO
Genetic subtypes of alpha 2-adrenergic receptors (AR) may mediate distinct physiological functions, and undergo differential cell type-specific regulation. Thus, these distinct receptor subtypes are possible targets for the development of subtype-selective drugs. We have analyzed the tissue distribution of two human alpha 2-adrenoceptor subtype gene mRNAs, alpha 2-C4 and alpha 2-C10, in normal human fetal and adult tissues. Both receptor subtype mRNAs were abundantly expressed in fetal brain and choroid plexus. In non-neural fetal tissues, alpha 2-C10 mRNA was detected in spleen, kidney, adrenal gland, and skin, while alpha 2-C4 transcripts were observed only in kidney and skin. Most regions of the adult brain also expressed both subtypes, but with marked quantitative differences. For example, cerebral cortex contained predominantly alpha 2-C10 mRNA, whereas the caudate nucleus expressed mostly alpha 2-C4 mRNA. In adult peripheral tissues, alpha 2-C10 mRNA expression was most abundant in spleen and renal cortex, and expression of alpha 2-C4 mRNA was strongest in renal cortex and medulla. These different expression patterns provide evidence for the differential regulation of the two alpha 2-adrenergic receptor genes and warrant further investigation with techniques capable of improved anatomical resolution. Regional differences in receptor subtype expression may be valuable for the development of new, subtype-selective pharmacological agents with more targeted actions compared to currently used alpha 2-adrenoceptor agonists and antagonists.
Assuntos
Encéfalo/metabolismo , RNA Mensageiro/biossíntese , Receptores Adrenérgicos alfa/genética , Vísceras/metabolismo , Animais , Encéfalo/embriologia , Linhagem Celular , Humanos , Hibridização de Ácido Nucleico , Especificidade de Órgãos/fisiologia , Sondas RNA , RNA Antissenso/genética , Ribonucleases , Vísceras/embriologiaRESUMO
We describe the identification of a novel laminin chain. Overlapping clones were isolated from a human fibrosarcoma HT1080 cell cDNA library spanning a total of 5,200 bp. A second set of clones contained an alternative 3' end sequence giving a total of 4,316 bp. The longer sequence contained an open reading frame for a 1,193-residue-long polypeptide. The alternative sequence was shortened at the carboxyl-terminal end coding for a 1,111-residue-long polypeptide. The amino acid sequence contained 21 amino acids of a putative signal peptide and 1,172 residues or alternatively 1,090 residues of a sequence with five distinct domains homologous to domains I-V in laminin chains. Comparison of the amino acid sequences showed that the novel laminin chain is homologous to the laminin B2 chain. However, the structure of the novel laminin chain isolated here differs significantly from that of the B2 chain in that it has no domain VI and domains V, IV, and III are shorter, resulting in a truncated laminin chain. The alternative sequence had a shortened domain I/II. In accordance with the current nomenclature, the chain characterized here is termed B2t. Calculation of possible chain interactions of laminin chains with the B2t chain domain I/II indicated that the B2t chain can replace the B2 chain in some laminin molecules. The gene for the laminin B2t chain (LAMB2T) was localized to chromosome 1q25-q31 in close proximity to the laminin B2 chain gene. Northern analysis showed that the B2t chain is expressed in several human fetal tissues but differently from the laminin B1 and B2 chains. By in situ hybridization expression of the B2t chain was localized to specific epithelial cells in skin, lung, and kidney as opposed to a general epithelial and endothelial cell expression of the laminin B2 chain in the same tissues.
Assuntos
Cromossomos Humanos Par 1 , Laminina/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Bandeamento Cromossômico , Mapeamento Cromossômico , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Fibrossarcoma , Biblioteca Gênica , Humanos , Células Híbridas , Substâncias Macromoleculares , Camundongos , Dados de Sequência Molecular , Poli A/genética , Poli A/isolamento & purificação , Conformação Proteica , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Células Tumorais CultivadasAssuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Receptores de Superfície Celular/genética , Animais , Mapeamento Cromossômico , Feto , Fatores de Crescimento de Fibroblastos/genética , Variação Genética , Humanos , Família Multigênica , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Fatores de Crescimento de FibroblastosRESUMO
Based on the map location of the aniridia (AN) locus in human chromosomal band 11p13, we have cloned a candidate AN cDNA (D11S812E) that is completely or partially deleted in two patients with AN. The less than 70 kb smallest region of overlap between the two deletions encompasses the 3' coding region of the cDNA. This cDNA, which spans over 50 kb of genomic DNA, detects a 2.7 kb message specifically within all tissues affected in AN. The predicted polypeptide product possesses a paired domain, a homeodomain, and a serine/threonine-rich carboxy-terminal domain, structural motifs characteristic of certain transcription factors. The concordance between expression and pathology, map location, structure, and predicted function argues that the cDNA corresponds to the AN gene.