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1.
Mol Biosyst ; 13(9): 1705-1708, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28681875

RESUMO

Hydrogen sulfide, an important gaseous signaling molecule in the human body, is known to protect cardiomyocytes from ischemia, a condition characterized by insufficient oxygen supply to the cells. Here we show that a nanosized H2S donor micelle releases H2S intracellularly and prevents cardiomyocyte apoptosis in an in vitro ischemia model.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Micelas , Isquemia Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Substâncias Protetoras/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Isquemia Miocárdica/patologia , Ratos
2.
Chem Commun (Camb) ; 53(2): 317-320, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-27853769

RESUMO

We demonstrate a novel system for inducing clustering of cell surface receptors via recognition peptide segments displayed on exosomes, leading to receptor activation. With this system, targeting of receptor-expressing cells and facilitation of the endocytic uptake of exosomes, which contained the anti-cancer protein saporin, were successfully achieved, leading to cell death.


Assuntos
Exossomos/metabolismo , Fragmentos de Peptídeos/metabolismo , Receptores de Superfície Celular/química , Receptores de Superfície Celular/metabolismo , Sequência de Aminoácidos , Células HeLa , Humanos , Fragmentos de Peptídeos/química , Transporte Proteico
3.
Bone Joint J ; 96-B(6): 795-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24891581

RESUMO

We examined the outcomes and levels of patient satisfaction in 202 consecutive cases of ultrasound-guided supraclavicular brachial plexus block (SBPB) in upper limb surgery performed between September 2007 and March 2010. All blocks were performed by orthopaedic surgeons using ultrasound visualisation with a high-frequency linear probe. The probe was placed in the coronal-oblique plane in the supraclavicular fossa, and the puncture was 'in-plane' from lateral to medial. Most of the blocks were performed with 0.75% ropivacaine/1% lidocaine (1:1), with or without adrenaline in 1:200 000 dilution. In 201 patients (99.5%) the brachial plexus block permitted surgery without conversion to general anaesthesia. The mean procedure time for block was 3.9 min (2 to 12), the mean waiting time for surgery was 34.1 min (10 to 64), the mean surgical time was 75.2 min (6 to 232), and the mean duration of post-anaesthetic analgesia was 437 min (171 to 992). A total of 20 patients (10%) developed a transient Horner's syndrome. No nerve injury, pneumothorax, arterial puncture or systemic anaesthetic toxicity were recorded. Most patients (96.7%) were satisfied with ultrasound-guided SBPB. This study demonstrates the efficacy and safety of ultrasound-guided SBPB for orthopaedic surgery on the upper limb.


Assuntos
Anestésicos Locais/administração & dosagem , Plexo Braquial/efeitos dos fármacos , Plexo Braquial/diagnóstico por imagem , Bloqueio Nervoso/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Clavícula , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente/estatística & dados numéricos , Prognóstico , Estudos Retrospectivos , Medição de Risco , Inquéritos e Questionários , Resultado do Tratamento , Extremidade Superior/cirurgia
4.
Arch Orthop Trauma Surg ; 127(3): 161-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17195933

RESUMO

Pycnodysostosis is a rare hereditary disease, characterized by systemic bone sclerosis. The most important orthopedic problem in this condition is the recurrent pathological fracture of long bones. In this paper, the surgical results for fractures of six limbs (three femurs and three tibias) in five cases of pycnodysostosis are reported. Five limbs achieved fracture union and union is developing in one tibia after intramedullary nail (IM) nailing or Ilizarov external fixation (IEF), although fracture line tends to persist for longer periods of time. One femoral fracture was treated by IM nailing, and one femoral and one tibial fracture were treated by IEF leading to final bone union. One femoral and one tibial fracture were initially treated by IEF, and were treated by IM nailing after re-fracture. One tibial fracture was initially treated by IEF leading to a failure of union, and was converted to IM nailing. All cases are able to walk; one case requires a single crutch. Infection was noted in two limbs after IM nailing following IEF. Fixation with IM nail was effective in preventing re-fracture as well as in alignment correction. Although the surgical technique is more difficult, IM nailing in the initial surgery may be a better choice for achieving successful union while reducing the risk of re-fracture or infection.


Assuntos
Disostoses/complicações , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas , Técnica de Ilizarov , Fraturas da Tíbia/cirurgia , Adulto , Disostoses/diagnóstico por imagem , Disostoses/patologia , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/etiologia , Fraturas da Tíbia/patologia , Resultado do Tratamento
5.
Protoplasma ; 229(1): 33-44, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17019526

RESUMO

The morphology of conidiogenesis and associated changes in microtubules, actin distribution and ultrastructure were studied in the basidiomycetous yeast Fellomyces fuzhouensis by phase-contrast, fluorescence, and electron microscopy. The interphase cell showed a central nucleus with randomly distributed bundles of microtubules and actin, and actin patches in the cortex. The conidiogenous mother cell developed a slender projection, or stalk, that contained cytoplasmic microtubules and actin cables stretched parallel to the longitudinal axis and actin patches accumulated in the tip. The conidium was produced on this stalk. It contained dispersed cytoplasmic microtubules, actin cables, and patches concentrated in the cortex. Before mitosis, the nucleus migrated through the stalk into the conidium and cytoplasmic microtubules were replaced by a spindle. Mitosis started in the conidium, and one daughter nucleus then returned to the mother via an eccentrically elongated spindle. The cytoplasmic microtubules reappeared after mitosis. A strong fluorescence indicating accumulated actin appeared at the base of the conidium, where the cytoplasm cleaved eccentrically. Actin patches then moved from the stalk together with the retracting cytoplasm to the mother and conidium. No septum was detected in the long neck by electron microscopy, only a small amount of fine "wall material" between the conidium and mother cell. Both cells developed a new wall layer, separating them from the empty neck. The mature conidium disconnected from the empty neck at the end-break, which remained on the mother as a tubular outgrowth. Asexual reproduction by conidiogenesis in the long-neck yeast F. fuzhouensis has unique features distinguishing it from known asexual forms of reproduction in the budding and fission yeasts. Fellomyces fuzhouensis develops a unique long and narrow neck during conidiogenesis, through which the nucleus must migrate into the conidium for eccentric mitosis. This is followed by eccentric cytokinesis. We found neither an actin cytokinetic ring nor a septum in the long neck, from which cytoplasm retracted back to mother cell after cytokinesis. Both the conidium and mother were separated from the empty neck by the development of a new lateral wall (initiated as a wall plug). The cytoskeleton is clearly involved in all these processes.


Assuntos
Basidiomycota/metabolismo , Citoesqueleto/metabolismo , Actinas/metabolismo , Basidiomycota/citologia , Basidiomycota/ultraestrutura , Ciclo Celular , Divisão Celular , Citoesqueleto/ultraestrutura , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Microtúbulos/metabolismo
6.
Arch Orthop Trauma Surg ; 126(1): 66-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16273377

RESUMO

A case of deformity and shortening after post-traumatic growth arrest treated using the Taylor Spatial Frame (Smith & Nephew, Tennessee, USA) is presented. This is the first report showing the application of the frame for post-traumatic deformity in the distal femur, and successful outcomes promise utilization of the frame even for correction of severe deformity in the distal femur.


Assuntos
Mau Alinhamento Ósseo/cirurgia , Fixadores Externos , Fraturas do Fêmur/cirurgia , Fraturas Mal-Unidas/cirurgia , Osteogênese por Distração/instrumentação , Adulto , Mau Alinhamento Ósseo/patologia , Desenho de Equipamento , Fraturas do Fêmur/patologia , Fraturas Mal-Unidas/patologia , Humanos , Masculino , Osteogênese por Distração/métodos , Resultado do Tratamento
7.
Int J Syst Evol Microbiol ; 53(Pt 4): 1149-1154, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12892143

RESUMO

Four novel, thermoacidophilic, crenarchaeotic cocci that grew anaerobically and heterotrophically were isolated from an acidic hot spring in the Philippines; two representative strains were characterized in detail. Most cells were regular cocci, 0.8-1.1 microm in width, which occurred singly or in pairs. They were non-motile and grew at 45-80 degrees C (optimum 70-75 degrees C) and pH 2.3-5.4 (optimum 3.5-4.0). They utilized starch, glycogen, gelatin, beef extract, yeast extract and peptone as carbon and energy sources. Growth was stimulated by the presence of sulfur as an electron acceptor. The lipid fraction contained cyclic and acyclic tetraether core lipids. The DNA G + C content was 31 mol%; phylogenetic analysis based on 16S rDNA sequences showed that the novel cocci represent an independent lineage in the phylum Crenarchaeota, distantly related to Acidilobus aceticus and an allied strain, NC12. Caldisphaera lagunensis gen. nov., sp. nov. is proposed to accommodate the four strains. The type strain is IC-154T (=JCM 11604T=MCC-UPLB 1331T=ANMR 0165T).


Assuntos
Crenarchaeota/classificação , Crenarchaeota/isolamento & purificação , Composição de Bases , Crenarchaeota/genética , Crenarchaeota/metabolismo , DNA Arqueal/química , DNA Arqueal/genética , DNA Ribossômico/genética , Água Doce/microbiologia , Temperatura Alta , Microscopia Eletrônica , Dados de Sequência Molecular , Fenótipo , Filipinas , Filogenia , RNA Arqueal/genética , RNA Ribossômico 16S/genética , Terminologia como Assunto
8.
Osteoarthritis Cartilage ; 11(4): 278-84, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12681954

RESUMO

OBJECTIVES: To examine the localization of bone morphogenetic protein (BMP)-2 mRNA and protein in human osteoarthritic (OA) articular cartilage and osteophyte. DESIGN: Five normal, four growing and 14 OA human cartilage samples, graded histomorphologically by Mankin Score, were studied by in situ hybridization and immunohistochemistry for the expression of BMP-2. RESULTS: BMP-2 mRNA was present in chondrocytes in neonatal growing articular cartilage, but was scarcely present in normal adult articular cartilage. In OA articular cartilage, BMP-2 mRNA and protein were detected in both clustering and individual chondrocytes in moderately or severely damaged OA cartilage. In moderately damaged OA cartilage, BMP-2 mRNA was localized in both upper and middle zone chondrocytes, but was not detected in deep layer chondrocytes. In severely damaged OA cartilage, cellular localization of BMP-2 mRNA was extended to the deep zone. In the area of osteophyte formation, BMP-2 mRNA was intensely localized in fibroblastic mesenchymal cells, fibrochondrocytes, chondrocytes and osteoblasts in newly formed osteophytic tissue. The pattern of BMP-2/4 immunolocalization was associated with that of mRNA localization. CONCLUSIONS: BMP-2 mRNA and BMP-2/4 were detected in cells appearing in OA tissues. BMP-2 was localized in cells of degenerating cartilage as well as osteophytic tissue. Given the negative localization of BMP-2 in normal adult articular cartilage, BMP-2 might be involved in the regenerating and anabolic activities of OA cells, which respond to cartilage damage occurring in osteoarthritis.


Assuntos
Proteínas Morfogenéticas Ósseas/análise , Cartilagem Articular/metabolismo , Osteoartrite do Joelho/metabolismo , RNA Mensageiro/análise , Fator de Crescimento Transformador beta , Idoso , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 4 , Condrócitos/metabolismo , Feminino , Humanos , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Masculino , Osteogênese/fisiologia
9.
Histochem Cell Biol ; 119(3): 233-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12649738

RESUMO

Localization and expression of mRNAs for sonic hedgehog (Shh) at a fracture site in the early phase postfracture were investigated by in situ hybridization and reverse transcription and polymerase chain reaction (RT-PCR). A closed fracture was made in the midshaft of the right tibia of 5-week-old ICR mice, and fractured sites were harvested prefracture (day 0) and on days 2 and 12. In situ hybridization revealed that transcripts for Shh were not detected on day 0, but they were detected in proliferating callus-forming cells in the periosteum and the surrounding tissue, and in the medullary cavity prior to apparent new cartilage and bone formation. Gli 1 (a signaling mediator for Shh) and bone morphogenetic protein-4 transcripts were colocalized with those for Shh transcripts on day 2. The RT-PCR showed that Shh mRNA was detected in the PCR product from day 2, but not from days 0 and 12. These findings are the first description about the activation of Shh gene in the early postfracture reaction.


Assuntos
RNA Mensageiro/metabolismo , Fraturas da Tíbia/metabolismo , Transativadores/genética , Animais , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Regeneração Óssea , Calo Ósseo/citologia , Proteínas Hedgehog , Hibridização In Situ , Fatores de Transcrição Kruppel-Like , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fraturas da Tíbia/patologia , Fatores de Tempo , Distribuição Tecidual , Fatores de Transcrição/genética , Proteína GLI1 em Dedos de Zinco
10.
Nature ; 416(6883): 823-6, 2002 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-11976676

RESUMO

Protons with energies up to approximately 10(15) eV are the main component of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking. Electrons are known to be accelerated to cosmic-ray energies in supernova remnants, and the shock waves associated with such remnants, when they hit the surrounding interstellar medium, could also provide the energy to accelerate protons. The signature of such a process would be the decay of pions (pi(0)), which are generated when the protons collide with atoms and molecules in an interstellar cloud: pion decay results in gamma-rays with a particular spectral-energy distribution. Here we report the observation of cascade showers of optical photons resulting from gamma-rays at energies of approximately 10(12) eV hitting Earth's upper atmosphere, in the direction of the supernova remnant RX J1713.7-3946. The spectrum is a good match to that predicted by pion decay, and cannot be explained by other mechanisms.

11.
Vox Sang ; 82(2): 72-5, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11906670

RESUMO

BACKGROUND AND OBJECTIVES: In Japan, eligibility for blood donation depends on blood specific gravity, which does not directly measure blood haemoglobin. Additionally, the criteria are not based on normal values. Therefore, we investigated the feasibility of predonation screening by using actual haemoglobin levels, and adopted a new criterion based on the normal range for men. MATERIALS AND METHODS: Using a portable device, we measured haemoglobin in 1032 prospective blood donors, then applied this method to all blood donations. The criterion for men was set at the 95th percentile of haemoglobin distribution, namely 13.0 g/dl and 13.5 g/dl, respectively, for 200-ml and 400-ml donations. That for women remained unchanged. RESULTS: The percentage of men ineligible by these criteria increased from 0.6 to 1.5%, while that of women decreased from 16.5 to 14.6%. Donors with abnormal haemoglobin levels were referred to hospitals. CONCLUSION: Predonation measurement of haemoglobin concentration, combined with the referral of those with abnormal values, provided a health benefit to that population.


Assuntos
Bancos de Sangue/normas , Doadores de Sangue , Hemoglobinas/análise , Adulto , Anemia Ferropriva/diagnóstico , Feminino , Humanos , Japão , Masculino , Valores de Referência , Gravidade Específica
12.
J Musculoskelet Neuronal Interact ; 2(4): 344-51, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15758426

RESUMO

Abnormalities of the epiphyseal growth plate that occur in collagen-induced arthritis (CIA) were studied. CIA was induced in 6-week-old Lewis rats by immunization with type II collagen. Radiographic examination revealed the early closure of the epiphyseal growth plate with growth retardation of the femur and tibia. Histological evaluation confirmed the early closure of the epiphyseal growth plate accompanied by decreased intensity of safranin-O staining indicating decreased amounts of proteoglycans in the extracellular matrix (ECM) of the cartilage. Immunohistochemical methods showed that the number of chondrocytes expressing matrix metalloproteinase (MMP)-3 and/or vascular endothelial growth factor (VEGF) increased in the growth plates of CIA rats. This study confirmed that disturbances of long bone growth with early closure of the epiphyseal growth plates occur in CIA. There appeared to be overexpression of MMP-3, which may be involved with proteoglycan degradation. Additionally, VEGF, which is associated with cartilage ossification and angiogenesis, might also play a role in this event. Further clarification of the mechanism of the growth disturbance in CIA may yield clinical benefits, especially in prevention of the premature closure of growth plate that is seen in juvenile rheumatoid arthritis and other diseases.

13.
Spine (Phila Pa 1976) ; 26(24): 2666-72, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11740352

RESUMO

STUDY DESIGN: Localization of cathepsins D, K, and L in degenerated intervertebral discs was examined by immunohistochemistry. OBJECTIVES: To determine the involvement of cathepsins in the pathomechanism of intervertebral disc degeneration by monitoring the immunolocalization of cathepsins in degenerated intervertebral disc tissue. SUMMARY OF BACKGROUND DATA: Cathepsins D, K, and L are enzymes that contribute to the matrix destruction seen in the articular cartilage affected by osteoarthritis and rheumatoid arthritis. However, little is known about the contribution of these cathepsins to intervertebral disc degeneration. METHODS: Paraffin-embedded sections of degenerated intervertebral disc tissue collected at the time of surgery (13 discs from 12 patients) were immunohistochemically stained with antibodies for cathepsins D, K, and L. For further characterization of the stained cells, immunohistochemical detection of CD68 and TRAP staining were performed. RESULTS: Hematoxylin and eosin staining revealed obvious signs of degeneration in all sections. Cathepsins D and L were immunolocalized in disc fibrochondrocytes at various sites exhibiting degeneration. Cathepsins K were found in tartrate-resistant acid phosphatase-positive multinucleated cells, in particular near the cleft within the cartilaginous endplate. However, few cells were positive for these cathepsins in anulus fibrosus that maintained the lamellar structure of collagen fibers. CONCLUSIONS: Marked expression of cathepsins D and L was observed at the site of degeneration. Cathepsins D and K localized in tartrate-resistant acid phosphatase-positive multinucleated cells existed at the cleft between the cartilaginous endplate and vertebral body. The site-specific localization of these cathepsins suggests the association of these proteinases with endplate separation and disorganization of the anulus fibrosus in degenerative spinal disorders.


Assuntos
Catepsina D/metabolismo , Catepsinas/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Catepsina K , Catepsina L , Cisteína Endopeptidases , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
14.
Spine (Phila Pa 1976) ; 26(22): 2414-20, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11707702

RESUMO

STUDY DESIGN: Apoptosis in cervical intervertebral disc cells and cartilaginous endplate cells was examined by the nick end labeling (TUNEL) technique during the process of natural aging and in a mouse experimental spondylosis model. OBJECTIVES: To determine the role of apoptosis in aging and degeneration of intervertebral discs by monitoring chronologic changes in the quantity and localization of apoptotic cells. SUMMARY OF BACKGROUND DATA: Apoptosis occurs within human intervertebral discs, but little is known about the pathologic significance of this process. On the other hand, the cartilaginous endplate is known to decrease in thickness and to disappear with aging and degeneration. The cause of this age-related change remains unclear. METHODS: A mouse spondylosis model was prepared via surgical resection of the posterior spinal element in 12 mice to examine the experimentally induced spondylosis process. Eighteen naturally aged mice were also used to examine the influence of aging. Paraffin-embedded midsagittal sections of the cervical spine were obtained 2, 3, 6, and 12 months after surgery in the spondylosis model and in the age-matched naturally aged mice, as well as in 4-week-old and 18-month-old naturally aged mice. Sections were stained with hematoxylin and eosin, safranin-O, and the TUNEL procedure. The number of apoptotic cells and vital cells were counted in the cartilaginous endplate of the intervertebral disc excluding the growth cartilage, and the degree of disappearance of the cartilaginous endplate was evaluated. RESULTS: Apoptosis, particularly noticeable in the cartilaginous endplate, increased with age and resulted in a marked decrease in cell density. Subsequently, the structure of the cartilaginous endplate began to disappear. Apoptosis was more evident and the structure of the cartilaginous endplate began to disappear more rapidly in the surgically treated group than in the naturally aged group. CONCLUSIONS: TUNEL-positive cells in the cartilaginous endplate increased with age, with destruction of the cartilaginous endplate after apoptosis (TUNEL-positive cell death). The application of the spondylosis model increased the incidence of apoptosis preceding the development of spondylosis. This suggests that apoptosis plays a role in the age-related changes seen in the cartilaginous endplate of the intervertebral disc and in the experimentally induced spondylosis process.


Assuntos
Envelhecimento/fisiologia , Apoptose , Cartilagem Articular/fisiopatologia , Vértebras Cervicais , Condrócitos/fisiologia , Disco Intervertebral , Osteofitose Vertebral/fisiopatologia , Animais , Cartilagem Articular/patologia , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos ICR , Osteofitose Vertebral/patologia
15.
Spine (Phila Pa 1976) ; 26(22): 2421-6, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11707703

RESUMO

STUDY DESIGN: Age-related fluctuations in insulin-like growth factor-I dependent proteoglycan synthesis in rat intervertebral disc cells were investigated. OBJECTIVES: The purpose of this study was to determine whether synthetic responses to insulin-like growth factor-I decline with age and to explore the possibility that an age-related increase in the expression of insulin-like growth factor binding proteins suppresses matrix synthesis in intervertebral disc cells. SUMMARY AND BACKGROUND DATA: Several studies have reported that the responsiveness of chondrocytes to insulin-like growth factor-I decreases with age and furthermore that this phenomenon may be related to increased expression of insulin-like growth factor binding proteins by chondrocytes. MATERIALS AND METHODS: Nucleus pulposus tissue and cells were obtained from the coccygeal vertebrae of 8-week-old, 40-week-old, and 120-week-old rats. Age-related changes in the expression of insulin-like growth factor-I and its receptor were assessed together with insulin-like growth factor-I dependent proteoglycan synthesis by the cultured nucleus pulposus cells. Also, western blot analysis of insulin-like growth factor binding protein-1 was carried out, and further examination was performed of insulin-like growth factor-I signal transduction through tyrosine phosphorylation of insulin receptor substrate-1, which is a signal transducer of insulin-like growth factor-I. RESULTS: Semiquantitative reverse transcription polymerase chain reaction analysis indicated that the expression of insulin-like growth factor-I receptor in 120-week cells decreased clearly in comparison with the cells of younger animals. By contrast, insulin-like growth factor-I dependent proteoglycan synthesis decreased with age, and the sharpest decline of synthesis was found between 8-week and 40-week cells, although the level of insulin-like growth factor-I/insulin-like growth factor-I receptor gene expression was maintained in 40-week-old animals. Consistent with the results of proteoglycan synthesis, the expression of phosphorylated insulin receptor substrate-1 decreased with age. Thus, the expression of insulin-like growth factor binding protein-1 and proteoglycan synthesis was investigated by use of Long R3 insulin-like growth factor-I, which was not influenced by insulin-like growth factor binding proteins. Insulin-like growth factor binding protein-1 was strongly expressed in 40-week cells in comparison with the expression in 8-week cells. Furthermore, proteoglycan synthesis in 40-week cells supplemented with Long R3 insulin-like growth factor-I was upregulated in comparison with that in 40-week cells supplemented with insulin-like growth factor-I. CONCLUSION: The present findings indicate that the age-related decline in insulin-like growth factor-I dependent proteoglycan synthesis in nucleus pulposus is caused, at least in part, by the increase in insulin-like growth factor binding proteins at the early stages of aging, and further suggest that a loss of proteoglycan synthesis during the late stages of aging is caused by the downregulation of insulin-like growth factor-I receptor in addition to an increase in insulin-like growth factor binding proteins.


Assuntos
Envelhecimento/fisiologia , Fator de Crescimento Insulin-Like I/análogos & derivados , Fator de Crescimento Insulin-Like I/fisiologia , Disco Intervertebral/metabolismo , Proteoglicanas/biossíntese , Animais , Células Cultivadas , Colágeno Tipo II/genética , Colágeno Tipo XI/genética , Expressão Gênica , Proteínas Substratos do Receptor de Insulina , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/biossíntese , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/farmacologia , Disco Intervertebral/citologia , Masculino , Fosfoproteínas/metabolismo , Fosforilação , Ratos , Ratos Wistar , Receptor IGF Tipo 1/genética , Região Sacrococcígea , Tirosina/metabolismo
16.
Histochem Cell Biol ; 116(3): 277-84, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11685558

RESUMO

Parathyroid hormone-related peptide (PTHrP), Indian hedgehog (Ihh), and patched (Ptc; a receptor for Ihh) were immunolocalized in tissue undergoing endochondral ossification in the human. PTHrP, Ihh, and Ptc were immunolocalized in prehypertrophic and hypertrophic chondrocytes in mature cartilage matrix. PTHrP and Ptc were immunostained in proliferating chondrocytes and perichondrial cells, whereas Ihh was not. PTHrP, Ihh, and Ptc showed positive immunostaining in osteoblasts in the bone-forming area. In the bone resorption site, PTHrP was immunolocalized in osteoclasts, whereas Ihh and Ptc were not. The present findings indicated that PTHrP, Ihh, and Ptc were associated with the process of endochondral ossification, and suggested the possible involvement of Ihh and PTHrP signaling in the regulation of proliferation and hypertrophy of chondrocytes in human chondrogenesis.


Assuntos
Osso e Ossos/metabolismo , Osteogênese , Proteínas/análise , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/fisiopatologia , Osso e Ossos/patologia , Osso e Ossos/fisiopatologia , Divisão Celular/genética , Condrócitos/metabolismo , Colágeno Tipo I/genética , Proteínas Hedgehog , Humanos , Hipertrofia , Imuno-Histoquímica , Hibridização In Situ , Proteínas de Membrana/análise , Proteínas de Membrana/genética , Osteoblastos/metabolismo , Osteocondroma/genética , Osteocondroma/metabolismo , Osteocondroma/fisiopatologia , Osteoclastos/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo , Receptores Patched , Polidactilia/genética , Polidactilia/metabolismo , Polidactilia/fisiopatologia , Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular , Transativadores/análise , Transativadores/genética
17.
Int J Syst Evol Microbiol ; 51(Pt 5): 1825-1829, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11594615

RESUMO

Two novel haloalkaliphilic archaea, strains C231T and C42, were isolated from a soda lake in China. Cells of the two strains were rod-shaped and gram-negative and colonies were bright red. They required at least 2.5 M NaCl for growth, with an optimum at 3.5 M NaCl, and grew over a pH range from 8.0 to 10.5, with an optimum at pH 8.5. Hypotonic treatment with less than 1.5 M NaCl caused cell lysis. They had similar polar lipid compositions, possessing the diphytanyl (C20:C20) and phytanyl-sesterterpanyl (C20:C25) diether derivatives of phosphatidylglycerol and phosphatidylglycerophosphate methyl ester and a minor phospholipid, PL1. No glycolipids were detected. Comparison of 16S rDNA sequences and morphological features placed them in the genus Natronobacterium. Detailed phenotypic characterization and DNA-DNA hybridization studies revealed that the two strains belong to a new species in the genus Natronobacterium, for which the name Natronobacterium nitratireducens sp. nov. is proposed. The type strain is C231T (= AS 1.1980T = JCM 10879T).


Assuntos
Água Doce/microbiologia , Natronobacterium/classificação , China , DNA Ribossômico/análise , Dados de Sequência Molecular , Natronobacterium/genética , Natronobacterium/crescimento & desenvolvimento , Natronobacterium/fisiologia , Hibridização de Ácido Nucleico , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio
18.
Eur Spine J ; 10(4): 289-94, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11563613

RESUMO

Localization and expression of cartilage-derived morphogenetic protein (CDMP)-1 in tissues at the site of ossification of the ligamentum flavum (OLF) were examined by immunohistochemistry and in situ hybridization. The CDMP-1 protein and messenger ribonucleic acid (mRNA) were localized in spindle-shaped cells and chondrocytes in the OLF tissues. CDMP-1 was not detected in cells in non-ossified sites. These data indicate that CDMP-1 is locally activated and localized in spindle-shaped cells and chondrocytes at the site of OLE. Given the previously reported promoting action of CDMP-1 for chondrogenesis, the current results suggest that CDMP-1 may be involved in the progression of OLF, leading to the narrowing of spinal canal and thus causing severe clinical manifestations.


Assuntos
Proteínas Morfogenéticas Ósseas , Substâncias de Crescimento/metabolismo , Ligamento Amarelo/metabolismo , Ossificação Heterotópica/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Idoso , Condrócitos/metabolismo , Fator 5 de Diferenciação de Crescimento , Humanos , Imuno-Histoquímica , Hibridização In Situ , Ligamento Amarelo/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética
19.
Skeletal Radiol ; 30(7): 402-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11499782

RESUMO

We report three cases of spinal osteoblastoma with ossification of the ligamentum flavum (OLF) adjacent to the tumor. The patients in this report, all young adults, had no symptoms except for back pain. Computed tomography (CT) demonstrated a typical radiolucent nidus in the spinal pedicle/lamina with a dense sclerotic rim. In addition, ectopic bone formation at the insertion point of the ligamentum flavum adjacent to the tumor was clearly illustrated. Magnetic resonance imaging (MRI) revealed the tumor and surrounding inflammatory responses, but OLF was not detected clearly. Histological examination revealed endochondral ossification of the ligamentum flavum that is quite unusual for normal young adults. Immunohistochemical assays in one case demonstrated that bone morphogenetic protein (BMP)-2/4 was expressed in the osteoblastic tumor cells. This case raises the possibility that BMPs secreted from the tumor cells triggered ectopic ossification in the spinal ligament.


Assuntos
Ligamentos , Ossificação Heterotópica , Osteoblastoma , Osteoma Osteoide , Neoplasias da Coluna Vertebral , Adulto , Proteínas Morfogenéticas Ósseas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Laminectomia , Ligamentos/patologia , Imageamento por Ressonância Magnética , Masculino , Ossificação Heterotópica/diagnóstico , Ossificação Heterotópica/patologia , Osteoblastoma/diagnóstico , Osteoblastoma/patologia , Osteoma Osteoide/diagnóstico , Osteoma Osteoide/patologia , Neoplasias da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/patologia , Tomografia Computadorizada por Raios X
20.
Virchows Arch ; 438(6): 612-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11469694

RESUMO

Calcifying tendinitis of rotator cuff tendons is a common and painful condition caused by ectopic calcification in humans. To examine the involvement of osteopontin (OPN), a potent regulator of calcium deposition on connective tissues, localization and expression of OPN protein and messenger (m)RNA were investigated in human tissue samples of calcified rotator cuff tendons. Immunohistochemistry demonstrated that OPN was localized in cells surrounding the calcified area. OPN was localized in two distinct cell types, i.e., fibroblast-like cells negative for CD68 and tartrate-resistant acid phosphatase (TRAP) and multinucleated macrophages positive for CD68 and TRAP. In situ hybridization revealed that the mRNA expression of OPN in these cells coincided with the immunohistochemistry results, and these results were supported by reverse transcriptase polymerase chain reaction analysis using human OPN-specific oligonucleotides. Cells located away from the calcified area did not express OPN. The present findings indicate the involvement of OPN in the process of calcification of rotator cuff tendons and suggest that OPN plays a role in such painful disorders through the actions of at least two cell types.


Assuntos
Calcinose/metabolismo , Manguito Rotador/metabolismo , Sialoglicoproteínas/metabolismo , Tendinopatia/metabolismo , Tendões/metabolismo , Fosfatase Ácida/metabolismo , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Artrografia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Isoenzimas/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Pessoa de Meia-Idade , Osteopontina , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Manguito Rotador/diagnóstico por imagem , Manguito Rotador/patologia , Sialoglicoproteínas/genética , Fosfatase Ácida Resistente a Tartarato , Tendinopatia/diagnóstico por imagem , Tendinopatia/patologia , Tendões/diagnóstico por imagem , Tendões/patologia
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