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Heat stress strongly triggers the nuclear localization of the molecular chaperone HSP70. Hikeshi functions as a unique nuclear import carrier of HSP70. However, how the nuclear import of HSP70 is activated in response to heat stress remains unclear. Here, we investigated the effects of heat on the nuclear import of HSP70. In vitro transport assays revealed that pretreatment of the test samples with heat facilitated the nuclear import of HSP70. Furthermore, binding of Hikeshi to HSP70 increased when temperatures rose. These results indicated that heat is one of the factors that activates the nuclear import of HSP70. Previous studies showed that the F97A mutation in Hikeshi in an extended loop induced an opening in the hydrophobic pocket and facilitated the translocation of Hikeshi through the nuclear pore complex. We found that nuclear accumulation of HSP70 occurred at a lower temperature in cells expressing the Hikeshi-F97A mutant than in cells expressing wild-type Hikeshi. Collectively, our results show that the movement of the extended loop may play an important role in the interaction of Hikeshi with both FG (phenylalanine-glycine)-nucleoporins and HSP70 in a temperature-dependent manner, resulting in the activation of nuclear import of HSP70 in response to heat stress.
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BACKGROUND: Leukodystrophies are genetic white matter disorders affecting the formation or maintenance of myelin. Among the recently discovered genetic defects associated with leukodystrophies, several genes converge on a common mechanism involving protein transcription/translation and ER stress response. METHODS: The genetic basis of a novel congenital leukodystrophy, associated with early onset spastic paraparesis, acquired microcephaly and optic atrophy was studied in six patients from three unrelated Ashkenazi-Jewish families. To this end we used homozygosity mapping, exome analysis, western blot (Hikeshi, HSF1-pS326 and b-actin) in patient fibroblasts, indirect immunofluorescence (HSP70 and HSF1) in patient fibroblasts undergoing heat shock stress, nuclear injection of plasmids expressing Hikeshi or EGFP in patient fibroblasts, in situ hybridization and Immunoblot analysis of Hikeshi in newborn and adult mouse brain. RESULTS: All the patients were homozygous for a missense mutation, p.Val54Leu, in C11ORF73 encoding HSP70 nuclear transporter protein, Hikeshi. The mutation segregated with the disease in the families and was carried by 1:200 Ashkenazi-Jewish individuals. The mutation was associated with undetectable level of Hikeshi in the patients' fibroblasts and with lack of nuclear HSP70 during heat shock stress, a phenomenon which was reversed upon the introduction of normal human Hikeshi to the patients cells. Hikeshi was found to be expressed in central white matter of mouse brain. CONCLUSIONS: These data underscore the importance of Hikeshi for HSP70 relocation into the nucleus. It is likely that in the absence of Hikeshi, HSP70 cannot attenuate the multiple heat shock induced nuclear phenotypes, leaving the cells unprotected during heat shock stress. We speculate that the sudden death of three of the six patients following a short febrile illness and the life-threatening myo-pericarditis in the fourth are the result of excess extra-nuclear HSP70 level which initiates cytokine release or provide target for natural killer cells. Alternatively, nuclear HSP70 might play an active role in stressed cells protection.
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Proteínas de Transporte/genética , Efeito Fundador , Judeus/genética , Leucoencefalopatias/genética , Mutação , Adolescente , Animais , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Pré-Escolar , Feminino , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Masculino , Camundongos , Atrofias Ópticas Hereditárias/genética , LinhagemRESUMO
Nuclear transport is mediated by transport factors, including the importin ß family members. The directionality of nuclear transport is governed by the asymmetrical distribution of the small GTPase Ran. Of note, importin α/ß-mediated import of classical nuclear localization signal (cNLS)--containing cargo is more efficient than other Ran-dependent import pathways that do not require importin α. In this study, we characterized the role of importin α in nuclear transport by examining import efficiencies of cNLS-cargo/importin α/ß complexes. We first depleted digitonin-permeabilized semi-intact cells of endogenous importin α and used the cells to show that the interaction between importin α and Nup153--a component of the nuclear pore complex (NPC)--is essential for efficient import of importin ß-binding domain containing substrates, but not other cargoes that directly bind to importin ß. Moreover, we found that the binding of importin α to Nup153 facilitates cNLS-mediated import, and demonstrated that importin α in import complexes and cargo-free importin α prebound to Nup153 promote efficient import of cNLS-containing proteins. This is the first in vitro study showing that in conjunction with Nup153, importin α contributes to directionally biased exit of cNLS-containing cargo to the nuclear side of NPCs.
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Transporte Ativo do Núcleo Celular , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , alfa Carioferinas/metabolismo , beta Carioferinas/metabolismo , Animais , Núcleo Celular/metabolismo , Células HeLa , Humanos , Camundongos , Sinais de Localização Nuclear , Ligação ProteicaRESUMO
The nuclear pore complex (NPC) is a macromolecular assembly consisting of approximately 30 different proteins called nucleoporins. Several nucleoporins are O-GlcNAcylated, which is a post-translational modification in which the monosaccharide ß-N-acetylglucosamine (GlcNAc) is attached to serine or threonine residues within proteins. However, the biological significance of this modification on nucleoporins remains obscure. Here we found that Nup62 and Nup88 protein levels were significantly decreased upon knockdown of O-GlcNAc transferase (OGT), which catalyzes the O-GlcNAcylation of intracellular proteins. Although Nup88, unlike Nup62, was not recognized by an anti-O-GlcNAc antibody or WGA-HRP, knockdown of Nup62 caused a reduction in Nup88 protein levels, suggesting that the observed decrease in Nup88 in OGT knocked-down cells is due to a decrease in Nup62. Furthermore, we found that Nup88 was preferentially associated with O-GlcNAcylated Nup62 compared with non-O-GlcNAcylated Nup62. These results indicate that Nup62 protein levels are primarily maintained by O-GlcNAcylation and that Nup88 is quantitatively regulated through its interaction with O-GlcNAcylated Nup62.
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Acetilglucosamina/metabolismo , Glicoproteínas de Membrana/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Regulação para Baixo , Técnicas de Silenciamento de Genes , Glicosilação , Células HeLa , Humanos , N-Acetilglucosaminiltransferases , Ligação Proteica , RNA Interferente Pequeno/metabolismoRESUMO
PURPOSE: The purpose of this study is to determine the process parameters of the laboratory-scale spray dryer affecting the solubility behavior and physical stability of solid dispersions. METHODS: Solid dispersions of the model drug (nilvadipine or nifedipine) and hypromellose (HPMC) (w/w: 1/1) were prepared using the laboratory-scale spray dryer. As process parameters, nitrogen flow rate, sample concentration and pump speed were investigated. The samples were characterized by dissolution tests, powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscope (SEM), and nanoscale thermal analysis (Nano-TA). The physical stability was monitored after 7 months storage at 25°C. RESULTS: Solubility behavior and physical stability were improved by setting the low nitrogen flow rate and high sample concentration. DSC showed that the physical state depends on the spray drying conditions, whereas, every sample showed the similar morphology from SEM results. The difference of solubility behavior and physical stability were found to come from the microstructural phase separation of the spray dried particles using a novel analytical technique (Nano-TA). CONCLUSIONS: This study demonstrated that nitrogen flow rate and sample concentration should be the critical parameters for the enhancements of the solubility and physical stability of solid dispersions.
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Bloqueadores dos Canais de Cálcio/química , Excipientes/química , Metilcelulose/análogos & derivados , Modelos Químicos , Nifedipino/análogos & derivados , Nifedipino/química , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Temperatura Alta/efeitos adversos , Derivados da Hipromelose , Cinética , Metilcelulose/química , Microscopia Eletrônica de Varredura , Difração de Pó , Pós , Controle de Qualidade , Solubilidade , Suspensões , Temperatura de TransiçãoRESUMO
The wide applications of the subcutaneous pedicle flap "lateral orbital flap" named by the author is presented. The flap is designed between the lateral canthus and the sideburn as a spindle or crescent shaped island 2- to 3-cm wide and 5-cm long. To reconstruct the upper or lower eyelids, the flap is elevated as thin as possible, whereas for the eye socket reconstruction, an adequate volume of subcutaneous fat tissue is attached to the flap. The pedicle is designed inferomedially for the reconstruction of the recipient, any shape of the flap can be designed. As the anatomic structure of the donor site is similar to the eyelid, the excellent result can be obtained both functionally and cosmetically. The donor site is primarily closed without a marked scar. The cases of reconstructions using lateral orbital flap for the upper eyelid and the eye socket in the anophtalmic condition are presented.
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Enucleação Ocular , Traumatismos Oculares/cirurgia , Neoplasias Oculares/cirurgia , Órbita/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Adolescente , Adulto , Pálpebras/cirurgia , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Oftalmológicos/métodos , Resultado do Tratamento , Adulto JovemRESUMO
To understand various intranuclear functions, it is important to know when, what, and how proteins enter the nucleus. Although many methods and commercial kits for nuclear fractionation have been developed, there are still no methods for obtaining a complete nuclear proteome. Soluble nuclear proteins are often lost during fractionation. We developed remarkably improved methods to obtain nuclear soluble fractions by optimizing the conditions of selective permeabilization of the plasma membrane. As a result, 10 million cells could be separated into the cytoplasmic and nuclear soluble fractions more precisely in a 1.5-mL test tube. Moreover, the addition of an inhibitor to prevent leakage from the nucleus retained small proteins in the nucleus. Because of the simple protocols and easy application for multiple samples, our methods are expected to be applied to various studies on spatiotemporal changes of dynamic nuclear proteins, such as signal transduction.
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Malignant skin tumors and precancerous lesions have a predilection to be located in the nasal dorsum or sidewall. Although invasive reconstructions have been presented, no simple and suitable method has yet been reported for this area. The flap presented herein, named the lateral nasal advancement flap, is designed on the adjacent lateral region of the sidewall or nasal dorsum and advanced in the medial direction. Two Burow's triangles are removed in the upper and lower portions of the flap: the upper triangle along the nasofacial sulcus and the lower triangle along the nasofacial sulcus and/or the alar groove. Excellent results were obtained in the two clinical cases described in this report. Neither a trap door deformity nor dog-ears developed in either case. The postsurgical scars followed the aesthetic lines and became inconspicuous. A distinct angle was formed in the nasofacial sulcus without anchor sutures. This surgical procedure is technically simple and is performed under local anesthesia. Although the flap is a cheek-based advancement flap, postsurgical scars do not remain in the cheek; instead, they are located in the nasofacial sulcus and alar groove. The lateral nasal advancement flap is recommended for reconstruction of the nasal sidewall and dorsum.
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To investigate the role of ghrelin, an endogenous ligand of the growth hormone secretagogue receptor, in diabetic gastroparesis, we evaluated the plasma ghrelin profile during the oral glucose tolerance test in 55 patients with diabetes (men/women: 36/19, mean +/- SE of age: 55.1 +/- 1.7 years) with or without gastroparesis (diagnosed by the (13)C-acetate breath test). We also further examined cardiac autonomic neuropathy by assessing 24-hour variation of the R-R interval in randomly selected 32 patients with diabetes (men/women: 23/9, mean +/- SE of age: 54.2 +/- 2.5 years), and evaluated the influence of autonomic neuropathy on ghrelin. The fasting plasma ghrelin level was significantly lower in diabetes mellitus with gastroparesis than in healthy controls (7.9 +/- 0.7 fmol/ml versus 16.6 +/- 5.3 fmol/ml, p = 0.006). Patients with diabetes with gastroparesis showed no decrease of plasma ghrelin after glucose loading, unlike patients without gastroparesis or healthy controls. Diabetes mellitus with autonomic neuropathy, but not those without it, also showed no decrease of plasma ghrelin after glucose loading. Diabetic gastroparesis may be related to ghrelin-associated neurohormonal abnormalities, but the pathophysiological meaning of this abnormal ghrelin response needs further clarification.
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Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Gastroparesia/complicações , Grelina/sangue , Glucose/administração & dosagem , Administração Oral , Adulto , Doenças do Sistema Nervoso Autônomo/sangue , Doenças do Sistema Nervoso Autônomo/complicações , Glicemia/análise , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/metabolismo , Eletrocardiografia Ambulatorial , Feminino , Gastroparesia/sangue , Gastroparesia/metabolismo , Grelina/metabolismo , Teste de Tolerância a Glucose , Cardiopatias/sangue , Cardiopatias/complicações , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Basal cell carcinoma (BCC) has a predilection for the periorbital region, which is a special, prominent, cosmetic, functional area to protect the eyeball. For squamous cell carcinoma and melanoma, extensive resection with reconstruction is performed. In contrast, for BCC, resection is often confined to a small to medium-sized area, necessitating higher-quality reconstructive surgery. We analyze the surgical outcomes of treatment for periorbital BCC, and evaluate reconstruction method after resection. Forty-nine patients with periorbital BCC had surgery in our hospital over 20 years. Age, gender of the patients, and size, localization, and histology of the tumor, and surgical procedures, and their early and late complications were analyzed retrospectively. BCC was most frequently occurred in the lower lid (55%), followed by inner canthus (19%), upper lid (17%), and outer canthus (9%). The histologic classifications were solid (80%), morphea (7%), mix (7%), superficial (2%), keratotic (2%), and adenoid (2%). Recurrence of the tumor was observed in 2 advanced cases in patients treated with resection of the tumor including surrounding tissue 5 mm from the margin. A rotation advancement cheek flap procedure was most frequently applied. Horizontal shift of the skin was most effective to prevent postoperative lagophthalmos. BCC occurred most frequently in the lower lid within the periorbital area. Rotation advancement of cheek flap with horizontal shift of the skin is most effective procedure in both appearance and function of the eyelid.
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Carcinoma Basocelular/cirurgia , Neoplasias Palpebrais/cirurgia , Retalhos Cirúrgicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Resultado do TratamentoRESUMO
PURPOSE: To develop a high-throughput formulation screening (HTFS) system for self-microemulsifying drug delivery system (SMEDDS) formulations. METHODS: Formulations were prepared by dispensing surfactants and a model compound (Nilvadipine) dissolved in ethanol and oil with a robotic liquid dispenser. Screenings of emulsion particle size and phase stability were conducted for selecting SMEDDS formulations by a turbidity assay. RESULTS: Formulations were prepared at 40 minute/96-formulation. Both the screenings were conducted at 1 minute/96-formulation. SMEDDS formulations and the most suitable hydrophilic surfactant (HS)/lipophilic surfactant (LS) combination, which formed the largest SMEDDS area on its corresponding phase diagram, were selected by SMEDDS-HTFS system with minimal manpower (one person) and compound consumption (0.2 mg/formulation). CONCLUSIONS: SMEDDS-HTFS system enabled rapid and efficient selections of SMEDDS formulations and the most suitable HS/LS combination for SMEDDS.
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Sistemas de Liberação de Medicamentos , Ensaios de Triagem em Larga Escala/métodos , Nifedipino/análogos & derivados , Tensoativos/química , Estabilidade de Medicamentos , Emulsões , Etanol/química , Nefelometria e Turbidimetria , Nifedipino/administração & dosagem , Nifedipino/química , Óleos/química , Tamanho da Partícula , Robótica , Fatores de TempoRESUMO
Appropriate cell growth conditions are limited to a narrow temperature range. Once the temperature is out of this range, cells respond to protect themselves, but temperature thresholds at which various intracellular responses occur, including nuclear transport systems, remain unclear. Using a newly developed precise temperature shift assay, we found that individual transport pathways have different sensitivities to a rise in temperature. Nuclear translocations of molecular chaperone HSP70s occur at a much lower temperature than the inhibition of Ran-dependent transport. Subsequently, importin (Imp) α/ß-dependent import ceases at a lower temperature than other Ran-dependent transport, suggesting that these are controlled by independent mechanisms. In vitro research revealed that the inhibition of Imp α/ß-dependent import is caused by the dysfunction of Imp α1 specifically at lower temperature. Thus, the thermosensitivity of Imp α1 modulates transport balances and enables the multistep shutdown of Ran-dependent transport systems according to the degree of heat stress.
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Proteínas de Choque Térmico HSP70/genética , Resposta ao Choque Térmico/genética , alfa Carioferinas/genética , Transporte Ativo do Núcleo Celular/genética , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citoplasma/genética , Células HeLa , Humanos , Chaperonas Moleculares/genética , Temperatura , beta Carioferinas/genéticaRESUMO
Objective: When hands suffer burns, the tendons and digital bones are rarely injured because of the quick withdrawal reflex away from the heat source. Hence, a consensus of opinion regarding the treatment of severe hand burns with osseous blood flow deficiency has not been reached among clinicians. Methods: The patient was a 28-year-old woman whose fingers were accidentally soaked in heated cooking oil (160°C-170°C) for approximately 1 minute. The result was fourth-degree (extending to the tendon) digital burns of the distal end of the proximal interphalangeal joint with blood flow deficiency to the skin, tendon, and bone. Results: We performed immediate reconstructive surgery using an abdominal bipediceled flap. Two weeks later, after the flap was separated, all fingers showed complete range of motion, restoration of the metacarpophalangeal joint, and a high range (0°-75°) of proximal interphalangeal joint mobility with an acceptable digital length. Conclusions: Our experience shows that immediate surgery is highly preferable for deep burns of the hand to avoid delayed intractable complications and to achieve better and faster results.
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Nuclear pore complexes (NPCs) maintain cellular homeostasis by mediating nucleocytoplasmic transport. Although cyclin-dependent kinases (CDKs) regulate NPC assembly in interphase, the location of NPC assembly on the nuclear envelope is not clear. CDKs also regulate the disappearance of pore-free islands, which are nuclear envelope subdomains; this subdomain gradually disappears with increase in homogeneity of the NPC in response to CDK activity. However, a causal relationship between pore-free islands and NPC assembly remains unclear. Here, we elucidated mechanisms underlying NPC assembly from a new perspective by focusing on pore-free islands. We proposed a novel framework for image-based analysis to automatically determine the detailed 'landscape' of pore-free islands from a large quantity of images, leading to the identification of NPC intermediates that appear in pore-free islands with increased frequency in response to CDK activity. Comparison of the spatial distribution between simulated and the observed NPC intermediates within pore-free islands showed that their distribution was spatially biased. These results suggested that the disappearance of pore-free islands is highly related to de novo NPC assembly and indicated the existence of specific regulatory mechanisms for the spatial arrangement of NPC assembly on nuclear envelopes.
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Quinases Ciclina-Dependentes/metabolismo , Poro Nuclear/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Linhagem Celular Tumoral , Células HeLa , Humanos , Glicoproteínas de Membrana/metabolismo , Membrana Nuclear/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , RatosRESUMO
When recombinant human bone morphogenetic protein-2 (rhBMP-2) is implanted in soft tissues, bony tissue is induced during the course of endochondral ossification. The relationship between endochondral ossification and vascularization is important in bone formation, and vascular endothelial growth factor (VEGF) is considered to play an important role in this process. In this study, the immunohistological localization of VEGF was investigated in rhBMP-2-induced ectopic endochondral ossification in the calf muscle of rats. In addition, the characteristics of anti-VEGF antibody-reactive cells were histologically investigated using electron microscopy to examine the cause of endochondral ossification induced by recombinant human bone morphogenetic protein-2. The role of VEGF in rhBMP-2-induced osteoinduction and vascular induction was studied by observing the relationship between the localizations of anti-VEGF antibody-reactive cells and vascularization. During the process of rhBMP-2-induced ectopic endochondral ossification, fibroblast-like cells, which were located at the margin of the implant and reactive to BMP-2 at 5 days, were positive for VEGF immunostaining. Hypertrophic chondrocytes appeared 9 days and osteoblasts appeared 14 to 21 days after implantation, and all these cells were reactive with anti-VEGF antibody. Bony trabeculae subsequently appeared in the muscle, and new blood vessels were formed alongside the trabeculae. When VEGF was added to rhBMP, more new blood vessels and bone were formed in the induced bone. These findings suggested that rhBMP-2 induced the differentiation of undifferentiated mesenchymal cells to chondrocytes and osteoblasts, and these differentiated cells expressed VEGF, creating an advantageous environment for vascularization in bony tissue.
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Proteínas Morfogenéticas Ósseas/farmacologia , Condrogênese/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Proteína Morfogenética Óssea 2 , Osso e Ossos/irrigação sanguínea , Osso e Ossos/metabolismo , Osso e Ossos/ultraestrutura , Cartilagem/irrigação sanguínea , Cartilagem/metabolismo , Cartilagem/ultraestrutura , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Músculo Esquelético , Ratos , Ratos WistarRESUMO
UNLABELLED: Previous studies in our laboratory demonstrated that portal vein or intraosseous administration of donor bone marrow cells for modulation of the central immune system is likely to be beneficial for allograft tolerance induction in rabbits. We recently reported that the severity of host conditioning for donor-specific tolerance induction was reduced without loss of efficacy by using a single intraosseous injection of donor bone marrow cells without immunosuppressive agent administration or T cell depletion. We now further investigated the feasibility and effectiveness of skin allografting using donor-specific tolerance to treat full-thickness burns. MATERIALS AND METHODS: Dutch rabbits were used as recipients, and Japanese white rabbits were used as donors. Three experimental groups of burned rabbits were studied. Group I, allograft control; group II, allograft plus total-body irradiation; group III, allograft plus total-body irradiation and bone marrow infusion. Allograft survival times were determined by macroscopic and histopathologic examinations. RESULTS: Mean (S.D.) skin allograft survival was as follows: group I, 13.2 (4.1) days; group II, 15.2 (3.7) days; group III, 108.4 (14.3) days. CONCLUSION: We have shown the potential to perform long-term skin allografts by the induction of donor-specific tolerance in a rabbit model of burn.
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Queimaduras/cirurgia , Sobrevivência de Enxerto , Transplante de Pele/métodos , Animais , Transplante de Medula Óssea/métodos , Queimaduras/patologia , Estudos de Viabilidade , Coelhos , Transplante Homólogo , Irradiação Corporal TotalRESUMO
BACKGROUND: Keloids are benign proliferations of fibroblasts, but their exact etiology and molecular pathogenesis are unknown. MATERIALS AND METHODS: Fibroblasts were isolated from the central and peripheral regions of keloids, and the growth behavior and molecular characteristics of the keloid fibroblasts were compared with those of age-adjusted normal dermal fibroblasts. RESULTS: Central (but not peripheral) keloid fibroblasts exhibited significantly increased growth and high levels of expression of transforming growth factor-beta (TGF-beta) receptor 1 and Smad 2/3. CONCLUSION: Proliferation of central keloid fibroblasts, which results in keloid formation, appears to mainly involve the TGF-beta/Smad pathway.
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Fibroblastos/fisiologia , Queloide/fisiopatologia , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Actinas/metabolismo , Receptores de Ativinas Tipo I/metabolismo , Adolescente , Adulto , Western Blotting , Técnicas de Cultura de Células , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Humanos , Queloide/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Pele/citologia , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad4/metabolismo , Regulação para CimaRESUMO
Previous studies in our laboratory have shown that giving bone marrow cells through the portal vein or intraosseous route is likely to be beneficial to tolerance of induction of allografts in rabbits. Using this model, we tested whether a less severe regimen for conditioning of the host can prevent rejection of allografts. Rabbits were given a single intraosseous injection of donor bone marrow cells and total body irradiation (7 Gy) and transplantation of skin and ear allografts. Mean skin allograft survival for this treatment was 88 days, which was similar to the results of our earlier study. A donor ear was accepted for more than a year with no signs of rejection. These results suggest that a single intraosseous injection of donor bone marrow cells is sufficient for induction of donor-specific tolerance in rabbits and that immunosuppressive agents may not be needed.
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Células da Medula Óssea , Orelha/cirurgia , Infusões Intraósseas , Transplante de Pele/métodos , Imunologia de Transplantes/fisiologia , Animais , Modelos Animais de Doenças , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Tolerância Imunológica , Masculino , Probabilidade , Coelhos , Fatores de Risco , Sensibilidade e Especificidade , Transplante de Pele/efeitos adversos , Transplante HomólogoRESUMO
INTRODUCTION: The present study was conducted to examine the effect of conjugated docosahexaenoic acid (CDHA) on cell growth, cell cycle progression, mode of cell death, and expression of cell cycle regulatory and/or apoptosis-related proteins in KPL-1 human breast cancer cell line. This effect of CDHA was compared with that of docosahexaenoic acid (DHA). METHODS: KPL-1 cell growth was assessed by colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; cell cycle progression and mode of cell death were examined by flow cytometry; and levels of expression of p53, p21Cip1/Waf1, cyclin D1, Bax, and Bcl-2 proteins were examined by Western blotting analysis. In vivo tumor growth was examined by injecting KPL-1 cells subcutaneously into the area of the right thoracic mammary fat pad of female athymic mice fed a CDHA diet. RESULTS: CDHA inhibited KPL-1 cells more effectively than did DHA (50% inhibitory concentration for 72 hours: 97 micromol/l and 270 micromol/l, respectively). With both CDHA and DHA growth inhibition was due to apoptosis, as indicated by the appearance of a sub-G1 fraction. The apoptosis cascade involved downregulation of Bcl-2 protein; Bax expression was unchanged. Cell cycle progression was due to G0/G1 arrest, which involved increased expression of p53 and p21Cip1/Waf1, and decreased expression of cyclin D1. CDHA modulated cell cycle regulatory proteins and apoptosis-related proteins in a manner similar to that of parent DHA. In the athymic mouse system 1.0% dietary CDHA, but not 0.2%, significantly suppressed growth of KPL-1 tumor cells; CDHA tended to decrease regional lymph node metastasis in a dose dependent manner. CONCLUSION: CDHA inhibited growth of KPL-1 human breast cancer cells in vitro more effectively than did DHA. The mechanisms of action involved modulation of apoptosis cascade and cell cycle progression. Dietary CDHA at 1.0% suppressed KPL-1 cell growth in the athymic mouse system.
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Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Ácidos Docosa-Hexaenoicos/química , Ácidos Docosa-Hexaenoicos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Neoplasias da Mama/patologia , Carcinoma/patologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiologia , Ácidos Docosa-Hexaenoicos/toxicidade , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias/métodos , Células Tumorais CultivadasRESUMO
FK506 is an immunosuppressant that is used widely in organ transplantation, and it has recently been recognized as effective for promoting the growth of bone grafts [J. Bone Miner. Res. 15 (2000) 1147]. In this study, we evaluated the influence of FK506 on osteoinduction by recombinant human bone morphogenetic protein-2 (rhBMP-2) using atelopeptide type I collagen as a carrier. We administered FK506 (1 mg/kg/day intramuscularly) on days -2 to 0, -2 to 7, and -2 to sacrifice. rhBMP-2 was implanted into the calf muscle of Wistar rats (thirty per group) and the implant was sampled on days 7, 14, and 21. Radiographic evaluation, histological examination, and biochemical analysis were performed. It was found that FK506 promoted the early stage of osteoinduction after short-term administration. However, long-term administration of this agent accelerated both bone formation and bone resorption. In order to use FK506 effectively for promoting bone growth, we must further examine the appropriate dose, method, and period of administration.