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1.
Acta Biomater ; 115: 197-209, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32814142

RESUMO

Hydrogels used in regenerative medicine are often designed to allow cellular infiltration, degradation, and neovascularization. Low molecular weight hydrogels (LMWHs), formed by self-assembly via non-covalent interactions, are gaining significant interest because they are soft, easy to use and injectable. We propose LMWHs as suitable body implant materials that can stimulate tissue regeneration. We produced four new LMWHs with molecular entities containing nucleic acid and lipid building blocks and analyzed the foreign body response upon subcutaneous implantation into mice. Despite being infiltrated with macrophages, none of the hydrogels triggered detrimental inflammatory responses. Most macrophages present in the hydrogel-surrounding tissue acquired an immuno-modulatory rather than inflammatory phenotype. Concomitantly, no fibrotic capsule was formed after three weeks. Our glyconucleolipid LMWHs exhibited different degradation kinetics in vivo and in vitro. LMWHs with high angiogenic properties in vivo, were found to release glyconucleoside (glucose covalently linked to thymidine via a triazole moiety) as a common by-product of in vitro LMWH degradation. Chemically synthesized glyconucleoside exhibited angiogenic properties in vitro in scratch assays with monolayers of human endothelial cells and in vivo using the chick chorioallantoic membrane assay. Collectively, LMWHs hold promise as efficient scaffolds for various regenerative applications by displaying good biointegration without causing fibrosis, and by promoting angiogenesis through the release of a pro-angiogenic degradation product. STATEMENT OF SIGNIFICANCE: The main limitations of biomaterials developed in the field of tissue engineering remains their biocompatibility and vascularisation properties. In this context, we developed injectable Low Molecular Weight Hydrogels (LMWH) exhibiting thixotropic (reversible gelation) and thermal reversible properties. LMWH having injectability is of great advantage since it allows for their delivery without wounding the surrounding tissues. The resulting gels aim at forming scaffolds that the host cells colonize without major inflammation, and that won't be insulated by a strong fibrosis reaction. Importantly, their molecular degradation releases a product (a glycosyl-nucleoside conjugate) promoting angiogenesis. In this sense, these LMWH represent an important advance in the development of biomaterials promoting tissue regeneration.


Assuntos
Células Endoteliais , Hidrogéis , Animais , Materiais Biocompatíveis , Heparina de Baixo Peso Molecular , Hidrogéis/farmacologia , Camundongos , Engenharia Tecidual
2.
Phys Rev Lett ; 109(14): 146603, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-23083266

RESUMO

Full electric-field control of spin orientations is one of the key tasks in semiconductor spintronics. We demonstrate that electric-field pulses can be utilized for phase-coherent ±π spin rotation of optically generated electron spin packets in InGaAs epilayers detected by time-resolved Faraday rotation. Through spin-orbit interaction, the electric-field pulses act as local magnetic field pulses. By the temporal control of the local magnetic field pulses, we can turn on and off electron spin precession and thereby rotate the spin direction into arbitrary orientations in a two-dimensional plane. Furthermore, we demonstrate a spin-echo-type spin drift experiment and find an unexpected partial spin rephasing, which is evident by a doubling of the spin dephasing time.

3.
Theriogenology ; 78(8): 1666-81, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22704386

RESUMO

A major challenge to retaining viability of frozen gametes and reproductive tissues is to understand and overcome species-specificities, especially because there is substantial diversity in cryobiological properties and requirements among cell types and tissues. Systematic studies can lead to successful post-thaw recovery, especially after determining: 1) membrane permeability to water and cryoprotectant, 2) cryoprotectant toxicity, 3) tolerance to osmotic changes, and 4) resistance to cooling and freezing temperatures. Although species-dependency ultimately dictates the ability of specific cells and tissues to survive freeze-thawing, there are commonalities between taxa that allow a protocol developed for one species to be useful information for another. This is the reason for performing comparative cryopreservation studies among diverse species. Our laboratory has compared cellular cryotolerance, especially in spermatozoa, in a diverse group of animals-from corals to elephants-for more than 30 yrs. Characterizing the biophysical traits of gametes and tissues is the most efficient way to develop successful storage and recovery protocols, but, such data are only available for a few laboratory, livestock, and fish species, with virtually all others (wild mammals, birds, reptiles, and amphibians) having gone unstudied. Nonetheless, when a rare animal unexpectedly dies, there is no time to understand the fundamentals of biophysics. In these emergencies, it is necessary to rely on experience and the best data from taxonomically-related species. Fortunately, there are some general similarities among most species, which, for example, allow adequate post-thaw viability. Regardless, there is a priority for more information on biophysical traits and freezing tolerance of distinctive biomaterials, especially for oocytes and gonadal tissues, and even for common, domesticated animals. Our colleague, Dr John Critser was a pioneer in cryobiology, earning that moniker because of his advocacy and devotion to understanding the differences (and similarities) among species to better store living genetic material.


Assuntos
Animais Selvagens , Criopreservação/veterinária , Gônadas/fisiologia , Oócitos/fisiologia , Espermatozoides/fisiologia , Anfíbios , Animais , Aves , Permeabilidade da Membrana Celular , Crioprotetores , Feminino , Masculino , Mamíferos , Osmose , Répteis , Especificidade da Espécie , Espermatozoides/citologia , Água
4.
Curr Med Chem ; 18(36): 5519-27, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22172062

RESUMO

At the first glance the vertebrate body appears to be symmetric, however, left and right sides are different. This is tightly controlled during embryonic development, and may as well affect the spatial occurrence of diseases. In the embryo, determination of the left and right sides takes place before and during gastrulation. Its failure results in heterotaxia, a diverse group of congenital laterality disorders characterized by left-right displacement of organs. In recent years, our knowledge about the molecular control of left-right asymmetry during embryonic development has grown considerably. However, almost nothing is known about the etiology of cancer laterality. Mammary carcinoma is 5 - 10% more likely to arise in the left breast. The left side of the body is also 10% more prone to melanoma development. Whereas the right predominance of lung, ovarian and testicular cancer might be explained by the greater organ mass on that side, possible reasons for left predominance of mammary carcinoma and melanoma are highly speculative. Sleeping behavior, handedness, nursing behavior and asymmetric sun exposure were named. A possible interrelation between the molecular control of left-right asymmetry and cancer has not yet been discussed in detail. Here we present an overview of molecules involved in both processes, focusing on laterality of breast cancer. Several secreted and membrane-bound growth factors such as Nodal, Lefty, FGF, HB-EGF and HGF as well as transcription factors (e.g. Pitx2, FoxA2) may be candidates with such overlapping functions. Studies on cancer laterality in transgenic mice are needed to make progress in this neglected research field.


Assuntos
Padronização Corporal/genética , Neoplasias da Mama/genética , Desenvolvimento Embrionário/genética , Fatores de Determinação Direita-Esquerda/genética , Animais , Neoplasias da Mama/metabolismo , Feminino , Humanos , Fatores de Determinação Direita-Esquerda/metabolismo , Masculino , Gravidez
5.
Cryobiology ; 60(2): 147-58, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19857482

RESUMO

Coral throughout the world are under threat. To save coral via cryopreservation methods, the Symbiodinium algae that live within many coral cells must also be considered. Coral juvenile must often take up these important cells from their surrounding water and when adult coral bleach, they lose their endosymbiotic algae and will die if they are not regained. The focus of this paper was to understand some of the cryo-physiology of the endosymbiotic algae, Symbiodinium, living within three species of Hawaiian coral, Fungia scutaria, Porites compressa and Pocillopora damicornis in Kaneohe Bay, Hawaii. Although cryopreservation of algae is common, the successful cryopreservation of these important coral endosymbionts is not common, and these species are often maintained in live serial cultures within stock centers worldwide. Freshly-extracted Symbiodinium were exposed to cryobiologically appropriate physiological stresses and their viability assessed with a Pulse Amplitude Fluorometer. Stresses included sensitivity to chilling temperatures, osmotic stress, and toxic effects of various concentrations and types of cryoprotectants (i.e., dimethyl sulfoxide, propylene glycol, glycerol and methanol). To determine the water and cryoprotectant permeabilities of Symbiodinium, uptake of radio-labeled glycerol and heavy water (D(2)O) were measured. The three different Symbiodinium subtypes studied demonstrated remarkable similarities in their morphology, sensitivity to cryoprotectants and permeability characteristics; however, they differed greatly in their sensitivity to hypo- and hyposmotic challenges and sensitivity to chilling, suggesting that standard slow freezing cryopreservation may not work well for all Symbiodinium. An appendix describes our H(2)O:D(2)O water exchange experiments and compares the diffusionally determined permeability with the two parameter model osmotic permeability.


Assuntos
Antozoários/microbiologia , Criopreservação , Dinoflagellida/fisiologia , Animais , Permeabilidade da Membrana Celular , Conservação dos Recursos Naturais , Criopreservação/métodos , Crioprotetores/farmacocinética , Crioprotetores/toxicidade , Óxido de Deutério , Dinoflagellida/classificação , Dinoflagellida/efeitos dos fármacos , Glicerol/farmacocinética , Glicerol/toxicidade , Pressão Osmótica , Especificidade da Espécie , Simbiose
6.
Cryobiology ; 58(1): 12-19, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18951888

RESUMO

In the past two decades, laboratories around the world have produced thousands of mutant, transgenic, and wild-type zebrafish lines for biomedical research. Although slow-freezing cryopreservation of zebrafish sperm has been available for 30 years, current protocols lack standardization and yield inconsistent post-thaw fertilization rates. Cell cryopreservation cannot be improved without basic physiological knowledge, which was lacking for zebrafish sperm. The first goal was to define basic cryobiological values for wild-type zebrafish sperm and to evaluate how modern physiological methods could aid in developing improved cryopreservation protocols. Coulter counting methods measured an osmotically inactive water fraction (Vb) of 0.37+/-0.02 (SEM), an isosmotic cell volume (V(o)) of 12.1+/-0.2 microm(3) (SEM), a water permeability (L(p)) in 10% dimethyl sulfoxide of 0.021+/-0.001(SEM)microm/min/atm, and a cryoprotectant permeability (P(s)) of 0.10+/-0.01 (SEM)x10(-3)cm/min. Fourier transform infrared spectroscopy indicated that sperm membranes frozen without cryoprotectant showed damage and lipid reorganization, while those exposed to 10% glycerol demonstrated decreased lipid phase transition temperatures, which would stabilize the cells during cooling. The second goal was to determine the practicality and viability of shipping cooled zebrafish sperm overnight through the mail. Flow cytometry demonstrated that chilled fresh sperm can be maintained at 92% viability for 24h at 0 degrees C, suggesting that it can be shipped and exchanged between laboratories. Additional methods will be necessary to analyze and improve cryopreservation techniques and post-thaw fertility of zebrafish sperm. The present study is a first step to explore such techniques.


Assuntos
Criopreservação/veterinária , Preservação do Sêmen/veterinária , Espermatozoides/metabolismo , Peixe-Zebra/metabolismo , Animais , Fenômenos Biofísicos , Permeabilidade da Membrana Celular , Tamanho Celular , Sobrevivência Celular , Criopreservação/métodos , Masculino , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Pressão Osmótica , Transição de Fase , Preservação do Sêmen/métodos , Espermatozoides/citologia
7.
Oncogene ; 28(2): 243-56, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18850004

RESUMO

Cancer cells have complex, unique characteristics that distinguish them from normal cells, such as increased growth rates and evasion of anti-proliferative signals. Global inhibition of class I and II histone deacetylases (HDACs) stops cancer cell proliferation in vitro and has proven effective against cancer in clinical trials, at least in part, through transcriptional reactivation of the p21(WAF1/Cip1)gene. The HDACs that regulate p21(WAF1/Cip1) are not fully identified. Using small interfering RNAs, we found that HDAC4 participates in the repression of p21(WAF1/Cip1) through Sp1/Sp3-, but not p53-binding sites. HDAC4 interacts with Sp1, binds and reduces histone H3 acetylation at the Sp1/Sp3 binding site-rich p21(WAF1/Cip1) proximal promoter, suggesting a key role for Sp1 in HDAC4-mediated repression of p21(WAF1/Cip1). Induction of p21(WAF1/Cip1) mediated by silencing of HDAC4 arrested cancer cell growth in vitro and inhibited tumor growth in an in vivo human glioblastoma model. Thus, HDAC4 could be a useful target for new anti-cancer therapies based on selective inhibition of specific HDACs.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/fisiologia , Proteínas de Neoplasias/fisiologia , Proteínas Repressoras/fisiologia , Fator de Transcrição Sp1/fisiologia , Acetilação , Animais , Sítios de Ligação , Neoplasias Ósseas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral/metabolismo , Embrião de Galinha , Inibidor de Quinase Dependente de Ciclina p21/genética , Epigênese Genética , Técnicas de Silenciamento de Genes , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Células HeLa/efeitos dos fármacos , Células HeLa/metabolismo , Inibidores de Histona Desacetilases , Histonas/metabolismo , Humanos , Proteínas de Neoplasias/antagonistas & inibidores , Osteossarcoma/patologia , Processamento de Proteína Pós-Traducional , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Proteínas Repressoras/antagonistas & inibidores , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/fisiologia
8.
Int Arch Allergy Immunol ; 146(2): 162-3, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18204283

RESUMO

We report on a 33-year-old female patient with indolent systemic mastocytosis and urticaria pigmentosa who died of an anaphylactic reaction after a yellow jacket sting. As she had no history of previous anaphylactic sting reaction, there was no testing performed in order to detect hymenoptera venom sensitization. But even if a sensitization had been diagnosed, no venom immunotherapy (VIT) would have been recommended. It is almost certain that VIT would have saved her life and it is most likely that VIT is indicated in some patients with mastocytosis with no history of anaphylactic sting reaction. However, no criteria have been established in order to allow a selection of mastocytosis patients eligible for such a 'prophylactic' VIT.


Assuntos
Anafilaxia/complicações , Anafilaxia/imunologia , Mordeduras e Picadas de Insetos/complicações , Mordeduras e Picadas de Insetos/imunologia , Mastocitose/imunologia , Adulto , Animais , Dessensibilização Imunológica/métodos , Evolução Fatal , Feminino , Humanos , Venenos de Vespas/imunologia , Vespas/imunologia
9.
Neuropediatrics ; 38(3): 143-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17985264

RESUMO

Alexander disease is a rare disorder of cerebral white matter due to a dysfunction of astrocytes. The most common infantile form presents as a megalencephalic leukodystrophy. Mutations of the GFAP gene, encoding Glial Fibrillary Acidic Protein, have been recognized as the cause of Alexander disease. Glial Fibrillary Acidic Protein is the major intermediate filament protein in astrocytes, its functional rod domain is conserved in sequence and structure among other intermediate filament proteins. We report here two cases of infantile Alexander disease with early onset and severe course, caused by DE NOVO mutations A364 V and Y366C. Both affected GFAP residues are part of a highly conserved coiled-coil trigger motif in the C-terminal end of segment 2B, probably required for the stability of intermediate filament molecules. Comparable effects are seen with mutations of the corresponding residues of the gene coding for keratin 14, another intermediate filament, this further supports the hypothesis that these positions of the trigger motif are generally critical for a normal function of intermediate filaments.


Assuntos
Doença de Alexander/genética , Éxons/genética , Proteína Glial Fibrilar Ácida/genética , Mutação/genética , Idade de Início , Alanina/genética , Doença de Alexander/patologia , Cisteína/genética , Análise Mutacional de DNA/métodos , Feminino , Lobo Frontal/patologia , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Estrutura Terciária de Proteína/genética , Tirosina/genética , Valina/genética
10.
Cryobiology ; 52(3): 454-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16626677

RESUMO

Coral species throughout the world are facing severe environmental pressures. Because of this, we began cryobiological studies on the sperm of the mushroom coral, Fungia scutaria. We determined that F. scutaria sperm had a mean length of 56 microm and head diameter of 2.5 microm, and a mean spontaneous ice nucleation temperature of -37.2 +/- 1.7 degrees C. When the sperm were exposed to the cryoprotectant glycerol for 5 or 20 min (at 10% v/v), no fertilized larvae were produced. However, when sperm were exposed for 20 min to propylene glycol (10% v/v), fertilizations were produced at the same rate as untreated control eggs and sperm (P > 0.05), but slightly less for dimethyl sulfoxide (10% v/v) (P < 0.05). Regardless, dimethyl sulfoxide caused less osmotic damage to the sperm membrane than did propylene glycol. Therefore, we used the dimethyl sulfoxide (10% v/v) to develop cryopreservation protocols that yielded good post-thaw morphology and motility (>95%) for coral sperm.


Assuntos
Antozoários , Criopreservação , Espermatozoides , Animais , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Fertilização/efeitos dos fármacos , Glicerol/farmacologia , Masculino , Propilenoglicol/farmacologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
11.
Poult Sci ; 85(2): 251-4, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16523623

RESUMO

Cryopreservation of avian germplasm is becoming better understood and more commonly practiced. However, one area that would be of great benefit for genome resource banking is the preservation of avian embryos. Little is know about the cryobiology of avian embryos, and they have never been successfully cryopreserved. However, it is likely that they share many of the challenges of other yolk-filled multicompartmental embryos. For example, the fish embryo has 1) a large overall size, resulting in a low surface-to-volume ratio, which retards water and cryoprotectant efflux/influx; 2) large-sized cells, such as the yolk, which could increase the likelihood of membrane disruption by intracellular ice formation; 3) compartments, such as the blastoderm and yolk, with differing permeability properties; and 4) susceptibility to chilling injury. Both the avian and fish systems share many physical and anatomical properties, and it is predicted that some of the same permeability barriers would exist in both as well. Although the systems are similar, some of the goals, and thus the practices, to protect the genome may be quite different. One of these major goals in avian developmental biology is to produce chicken:chicken transgenic animals, especially those with germ line transmission. Producing efficient germ line transmissions and being able to cryopreserve these transmissions would be extremely beneficial to both basic and agricultural science. This could be accomplished through the cryopreservation of embryonic gonadal tissue followed by grafting into a host. The gonadal/tail-graft system would provide an advantage for cryopreservation because it is small (in comparison with the whole embryo), has fairly uniform tissue, and contains the essential primordial germ line cells capable of recreating the genetic line of interest. Moreover, because the chicken is such a robust model for most other avian species, the cryopreservation of the gonadal/tail-graft may potentially open up similar treatments for other commercially important species.


Assuntos
Aves/embriologia , Aves/genética , Criopreservação/veterinária , Peixes/embriologia , Animais , Animais Geneticamente Modificados/genética , Embrião de Galinha , Galinhas/genética , Criopreservação/métodos , Feminino , Gônadas/embriologia , Masculino , Bancos de Tecidos
12.
Cryobiology ; 52(1): 33-47, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16337183

RESUMO

Coral species throughout the world's oceans are facing severe environmental pressures. We are interested in conserving coral larvae by means of cryopreservation, but little is known about their cellular physiology or cryobiology. These experiments examined cryoprotectant toxicity, dry weight, water and cryoprotectant permeability using cold and radiolabeled glycerol, spontaneous ice nucleation temperatures, chilling sensitivity, and settlement of coral larvae. Our two test species of coral larvae, Pocillopora damicornis (lace coral), and Fungia scutaria (mushroom coral) demonstrated a wide tolerance to cryoprotectants. Computer-aided morphometry determined that F. scutaria larvae were smaller than P. damicornis larvae. The average dry weight for P. damicornis was 24.5%, while that for F. scutaria was 17%, yielding osmotically inactive volumes (V(b)) of 0.22 and 0.15, respectively. The larvae from both species demonstrated radiolabeled glycerol uptake over time, suggesting they were permeable to the glycerol. Parameter fitting of the F. scutaria larvae data yielded a water permeability 2 microm/min/atm and a cryoprotectant permeability = 2.3 x 10(-4) cm/min while modeling indicated that glycerol reached 90% of final concentration in the larvae within 25 min. The spontaneous ice nucleation temperature for F. scutaria larvae in filtered seawater was -37.8+/-1.4 degrees C. However, when F. scutaria larvae were chilled from room temperature to -11 degrees C at various rates, they exhibited 100% mortality. When instantly cooled from room temperature to test temperatures, they showed damage below 10 degrees C. These data suggest that they are sensitive to both the rate of chilling and the absolute temperature, and indicate that vitrification may be the only means to successfully cryopreserve these organisms. Without prior cryopreservation, both species of coral settled under laboratory conditions.


Assuntos
Antozoários/fisiologia , Larva/crescimento & desenvolvimento , Reprodução/fisiologia , Animais , Antozoários/crescimento & desenvolvimento , Permeabilidade da Membrana Celular/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/metabolismo , Crioprotetores/farmacologia , Congelamento , Glicerol/metabolismo , Glicerol/farmacologia , Gelo , Larva/fisiologia , Sensibilidade e Especificidade , Especificidade da Espécie , Temperatura
13.
Eur J Med Res ; 10(5): 183-6, 2005 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-15946916

RESUMO

Immune response to intestinal bacteria and genetic predisposition seem to play a crucial role in the pathogenesis of inflammatory bowel disease. A single nucleotide polymorphism in the promoter of the lipopolysaccharide-receptor CD14 gene (T/C at position -159) has recently been described. To evaluate the role of the CD14 gene in anti-inflammatory therapy, the functionally relevant T(-159)-->C promoter polymorphism has been genotyped in 72 patients with inflammatory bowel disease and associated with the cumulative steroid dose. Cumulative corticosteroid dose was significantly higher in ulcerative colitis patients with the TT genotype (2447.7 +/- 927.0 mg/yr) compared with the CT genotype (142.3 +/- 142.3 mg/yr, p=0.016) and the CC genotype (391.7 +/- 272.7 mg/yr, p=0.047). In contrast, in patients with Crohn's disease there was no significant difference of the cumulative corticosteroid doses between the various T(-159)-->C promoter CD14 genotypes. An altered immune response to lipopolysaccharides with influence on the anti-inflammatory therapy seems to play a role in the genetic predisposition to ulcerative colitis. Genetic stratification will lead to the development of individualized therapies in inflammatory bowel disease.


Assuntos
Corticosteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/genética , Doença de Crohn/tratamento farmacológico , Doença de Crohn/genética , Receptores de Lipopolissacarídeos/genética , Adulto , Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética
14.
Dig Liver Dis ; 37(3): 159-61, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15888279

RESUMO

BACKGROUND AND AIMS: Linkage of inflammatory bowel diseases to chromosome 12p13.2-q24.1 (IBD2) has been confirmed in several genome wide screens. The STAT6 gene is located within this chromosomal region. The transcription factor STAT6 is involved in the regulation of the TH1/TH2 immune response. Increased production of TH1 cytokines is crucial in the pathogenesis of Crohn's disease. PATIENTS AND METHODS: Therefore, we genotyped a single nucleotide polymorphism in the 3' untranslated region of the STAT6 gene (G2964A) in 243 patients with Crohn's disease, 100 patients with ulcerative colitis and 548 healthy controls. RESULTS: In comparison to controls, the G allele and the GG genotype frequencies were significantly increased only in Crohn's disease patients without a variation in the CARD15 gene (p<0.03 and p<0.02, respectively). CONCLUSIONS: Alterations in the STAT6 pathway may play a crucial role in the pathogenesis of distinct subgroups of patients with Crohn's disease.


Assuntos
Colite Ulcerativa/genética , Doença de Crohn/genética , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais/genética , Transativadores/genética , Adulto , Ligação Genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Pessoa de Meia-Idade , Proteína Adaptadora de Sinalização NOD2 , Fator de Transcrição STAT6
16.
Artigo em Inglês | MEDLINE | ID: mdl-15533783

RESUMO

Fish embryos have never been successfully cryopreserved because of the low permeability of cryoprotectants into the yolk. Recently, we used aquaporin-3 fused with a green fluorescent protein (AQP3GFP) to modify the zebrafish embryo, and demonstrated that the pores functioned physiologically. This increased the water and cryoprotectant permeability of the membranes. We have continued our work on AQP3-modified embryos and here we report their developmental expression of AQP3, the success of various culture media on their survival and development, and their reproductive success. The AQP3GFP expression begins within 30 m after the mRNA AQP3GFP injection into the yolk of the 1- to 4-cell embryo. This expression is distributed in the membranes throughout the blastoderm and the yolk syncytial layer within 24 h. It diminishes after 96 h. We found no difference in the survival or normal development of embryos from AQP3GFP or wild-type adults. Additionally, zebrafish embryos did not require special culture medium to survive after AQP3GFP modification. In fact, they survived best in embryo medium (ca. 40 mOsm). Embryos reared entirely in embryo medium had a higher percent survival and a higher percent normal development than those exposed to a high osmolality sucrose culture medium (ca. 330 mOsm). The mechanism whereby these embryos can maintain their internal osmolality in a hypoosmotic solution with water channels in their membranes is unknown.


Assuntos
Aquaporinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Animais , Aquaporina 3 , Meios de Cultura , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Microscopia Confocal , Concentração Osmolar , Cloreto de Sódio/farmacologia , Sacarose/farmacologia , Taxa de Sobrevida
17.
Cryobiology ; 49(2): 181-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15351689

RESUMO

Although fish embryos have been used in a number of slow-freezing cryopreservation experiments, they have never been successfully cryopreserved. In part this is because little is known about whether ice forms within the embryo during the slow-freezing dehydration process. Therefore, we examined the temperature of intraembryonic ice formation (T(IIF)) and the temperature of extraembryonic ice formation (T(EIF)), using a cryomicroscope. We used both unmodified zebrafish embryos and those with water channels (aquaporin-3 or AQP3) inserted into their membranes to increase permeability to water and cryoprotectants, examined at 100% epiboly to the 6-somite stage. In these experiments we examined: (1) the spontaneous freezing of (external) solutions; (2) the spontaneous freezing of solutions containing embryos; (3) the effect of preloading the embryos with cryoprotectants on T(IIF); (4) whether preloading the embryos with cryoprotectant helps in survival after nucleating events in the solution; and (5) the damaging effects of extracellular nucleation events versus solution toxicity on the embryos. The solutes alone (embryo medium--EM, sucrose culture medium, 1 M propylene glycol in EM, and 1 M propylene glycol in a sucrose culture medium) froze at -14.9 +/- 1.1, -17.0 +/- 0.3, -17.8 +/- 1.0, and -17.7 +/- 1.4, respectively. There was no difference amongst these means (P > 0.05), thus adding cryoprotectant did not significantly lower the nucleation point. Adding embryos (preloaded with cryoprotectant or not) did not change the basic freezing characteristics of these solutes. In all these experiments, (T(EIF)) equaled (T(IIF)), and there was no difference in the freezing point of the solutions with or without the embryos (P > 0.05). Additionally, there was no difference in the freezing characteristics of embryos with and without aquaporins (P > 0.05). The formation of intraembryonic ice was lethal to the zebrafish embryos in all cases. But this lethal outcome was not related to solution injury effects, because 88-98% of embryos survived when exposed to a higher solute concentration with no ice present. Taken together, these data suggest that slow-freezing is not a suitable option for zebrafish embryos. The mechanism of this high temperature nucleation event in zebrafish embryos is still unknown.


Assuntos
Criopreservação/métodos , Peixe-Zebra , Animais , Crioprotetores , Gelo , Peixe-Zebra/embriologia
18.
Hautarzt ; 55(7): 653-7, 2004 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-15146276

RESUMO

We report on a patient with terbinafine-induced SCLE covering clinical, histopathological and serological findings. Positive serological results included ANA, SS-A (Ro)-antibodies and anti-histone-antibodies with specificity for H1 and H3. The literature on terbinafine-induced SCLE is reviewed. We discuss H1- and H3-specific anti-histone antibodies as a possible diagnostic criterion of drug-induced SCLE.


Assuntos
Antifúngicos/efeitos adversos , Toxidermias/diagnóstico , Lúpus Eritematoso Cutâneo/induzido quimicamente , Naftalenos/efeitos adversos , Onicomicose/tratamento farmacológico , Idoso , Antifúngicos/uso terapêutico , Toxidermias/patologia , Feminino , Humanos , Lúpus Eritematoso Cutâneo/diagnóstico , Naftalenos/uso terapêutico , Pele/patologia , Terbinafina
19.
Hautarzt ; 54(3): 256-64, 2003 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-12634995

RESUMO

BACKGROUND AND OBJECTIVE: Total skin electron beam therapy (TSEBT) is an important therapeutic option for the treatment of mycosis fungoides. The aim of this study was to find out long term results in 10 patients with the clinical and histological diagnosis of mycosis fungoides. PATIENTS AND METHODS: Between 1982 and 1997 we performed a total skin electron beam therapy in 10 patients. One patient was in stage I A; 5, in stage I B; 3, in stage II B; and one, in stage IV A. The indication for TSEBT was disease progression in spite of PUVA therapy. The doses of electron beam therapy were 30- 36 Gy at 5-6 MeV. In 7 of 10 cases additional local electron beam therapy was given, because individual lesions persisted or recurred after a short time. RESULTS: Complete remission was achieved in 5 patients. The follow- up has been up to 10 years. One patient died of systemic lymphoma 10 years after electron beam therapy. Three patients died of illnesses unrelated to mycosis fungoides. One patient developed a high grade T-cell lymphoma. CONCLUSIONS: Total skin electron beam therapy is a very effective, but technically difficult therapy for mycosis fungoides, especially in stage I B and II B. Particularly interesting has been the long duration of complete response of three patients, who had follicular mucinosis preceding their mycosis fungoides.


Assuntos
Micose Fungoide/radioterapia , Neoplasias Cutâneas/radioterapia , Irradiação Corporal Total , Adulto , Idoso , Elétrons/uso terapêutico , Feminino , Seguimentos , Humanos , Metástase Linfática/radioterapia , Masculino , Pessoa de Meia-Idade , Micose Fungoide/patologia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Retratamento , Pele/patologia , Neoplasias Cutâneas/patologia
20.
Cell Calcium ; 32(3): 131-41, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12208233

RESUMO

It is thought that a plasma membrane Ca(2+)-transport ATPase (PMCA) and a Na(+)/Ca(2+)-exchange (NCE) mechanism are involved in epithelial Ca(2+) transport (ECT) in a variety of crustacean epithelia. The sternal epithelium of the terrestrial isopod Porcellio scaber was used as a model for the analysis of Ca(2+)-extrusion mechanisms in the hypodermal epithelium. Using RT-PCR, we amplified a cDNA fragment of 1173 bp that encodes a protein sequence possessing 72% identity to the PMCA from Drosophila melanogaster and a cDNA fragment of 791 bp encoding a protein sequence with 50% identity to the NCE from Loligo opalescens. Semiquantitative RT-PCR revealed that the expression of both mRNAs increases from the non-Ca(2+)-transporting condition to the stages of CaCO(3) deposit formation and degradation. During Ca(2+)-transporting stages, the expression of PMCA and NCE was larger in the anterior sternal epithelium (ASE) than in the posterior sternal epithelium (PSE). The results demonstrate for the first time the expression of a PMCA and a NCE in the hypodermal epithelium of a crustacean and indicate a contribution of these transport mechanisms in ECT.


Assuntos
ATPases Transportadoras de Cálcio/biossíntese , Células Epiteliais/metabolismo , Isópodes/metabolismo , Trocador de Sódio e Cálcio/biossíntese , Regulação para Cima/fisiologia , Sequência de Aminoácidos/fisiologia , Animais , ATPases Transportadoras de Cálcio/análise , ATPases Transportadoras de Cálcio/genética , Epiderme/química , Epiderme/metabolismo , Células Epiteliais/química , Isópodes/química , Isópodes/genética , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Trocador de Sódio e Cálcio/análise , Trocador de Sódio e Cálcio/genética
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