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1.
Osteoporos Int ; 34(7): 1207-1221, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37067545

RESUMO

This study investigated the long-term survival and incidence of secondary fractures after fragility hip fractures. The 5-year survival rate was 62%, and the mortality risk was seen in patients with GNRI < 92. The 5-year incidence of secondary fracture was 22%, which was significantly higher in patients with a BMI < 20. BACKGROUND: Malnutrition negatively influences the postoperative survival of patients with fragility hip fractures (FHFs); however, little is known about their association over the long term. OBJECTIVE: This study evaluated the ability of the geriatric nutritional risk index (GNRI) as a risk factor for long-term mortality after FHFs. METHODS: This study included 623 Japanese patients with FHFs over the age of 60 years. We prospectively collected data on admission and during hospitalization and assessed the patients' conditions after discharge through a questionnaire. We examined the long-term mortality and the incidence of secondary FHFs and assessed the prognostic factors. RESULTS: The mean observation period was 4.0 years (range 0-7 years). The average age at the time of admission was 82 years (range 60-101 years). The overall survival after FHFs (1 year, 91%; 5 years, 62%) and the incidence of secondary FHFs were high (1 year, 4%; 5 years, 22%). The multivariate Cox proportional hazard analysis revealed the risk factors for mortality as older age (hazard ratio [HR] 1.04), male sex (HR 1.96), lower GNRI score (HR 0.96), comorbidities (malignancy, HR 2.51; ischemic heart disease, HR 2.24; revised Hasegawa dementia scale ≤ 20, HR 1.64), no use of active vitamin D3 on admission (HR 0.46), and a lower Barthel index (BI) (on admission, HR 1.00; at discharge, HR 0.99). The GNRI scores were divided into four risk categories: major risk (GNRI, < 82), moderate risk (82-91), low risk (92-98), and no risk (> 98). Patients at major and moderate risks of GNRI had a significantly lower overall survival rate (p < 0.001). Lower body mass index (BMI) was also identified as a prognostic factor for secondary FHFs (HR 0.88 [p = 0.004]). CONCLUSIONS: We showed that older age, male sex, a lower GNRI score, comorbidities, and a lower BI are risk factors for mortality following FHFs. GNRI is a novel and simple predictor of long-term survival after FHFs.


Assuntos
Fraturas do Quadril , Desnutrição , Humanos , Masculino , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Avaliação Nutricional , Prognóstico , Desnutrição/complicações , Desnutrição/epidemiologia , Fraturas do Quadril/etiologia , Fatores de Risco , Avaliação Geriátrica , Estado Nutricional , Estudos Retrospectivos
2.
Nat Genet ; 24(3): 279-82, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700183

RESUMO

The cell-surface molecule Cd9, a member of the transmembrane-4 superfamily, interacts with the integrin family and other membrane proteins. and is postulated to participate in cell migration and adhesion. Expression of Cd9 enhances membrane fusion between muscle cells and promotes viral infection in some cells. Fertilization also involves membrane fusion, between gametes. In mammals, the sperm binds to microvilli on the egg surface, and sperm-egg membrane fusion first occurs around the equatorial region of the sperm head12. The fused membrane is then disrupted, and the sperm nucleus as well as the cytoplasm is incorporated into the egg. Cd9 is expressed on the plasma membrane of the mouse egg, and an anti-Cd9 monoclonal antibody inhibits sperm-egg surface interactions. We generated Cd9 mice and found that homozygous mutant females were infertile. Sperm-egg binding was normal, but sperm-egg fusion was almost entirely inhibited in eggs from Cd9 females. Intracellular Ca2 oscillations, which signal fertilization, were absent in almost all mutant eggs; in rare cases, a response occurred after a long time period. In normal animals, Cd9 molecules were expressed on the egg microvilli and became densely concentrated at the sperm attachment site. Thus, our results show that Cd9 is important in the gamete fusion process at fertilization.


Assuntos
Antígenos CD/fisiologia , Fusão Celular , Glicoproteínas de Membrana , Óvulo/metabolismo , Interações Espermatozoide-Óvulo , Animais , Antígenos CD/genética , Sinalização do Cálcio , Adesão Celular , Feminino , Infertilidade Feminina/genética , Masculino , Camundongos , Camundongos Knockout , Microvilosidades/metabolismo , Óvulo/ultraestrutura , Tetraspanina 29
3.
Vet J ; 296-297: 105992, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37164121

RESUMO

Tumor-associated macrophages are abundant infiltrating cells in the tumor microenvironment (TME). Macrophages can be classified into several types of subsets based on their immune responses. Among those subsets, M2 macrophages contribute to anti-inflammatory responses and create an immunosuppressive environment that promotes tumor cell proliferation. In a previous study, human cancer patients with high M2 macrophages showed a worse prognosis for many types of tumors. However, studies examining the relationship between M2 macrophages and clinical outcomes in canine tumors are limited. In the previous human and canine studies, CD204 has been used as the marker for detecting M2 macrophages. Then we evaluated CD204+ and total macrophages infiltration and its association with clinical outcomes in canine solid tumors. In this study, we examined dogs with oral malignant melanoma (OMM), pulmonary adenocarcinoma (PA), hepatocellular carcinoma (HCC), and transitional cell carcinoma (TCC). Compared to healthy tissues, CD204+ and total macrophages were increased in OMM, PA, and TCC, but not in HCC. High CD204+ macrophage levels were significantly associated with lung metastasis in TCC (P = 0.030). Kaplan-Meier analysis revealed that high CD204+ macrophage levels were associated with shorter overall survival (OS) in canine patients with PA (P = 0.012) and TCC (P = 0.0053). These results suggest that CD204+ macrophages contribute to tumor progression and could be a prognostic factor in dogs with PA and TCC.


Assuntos
Carcinoma Hepatocelular , Carcinoma de Células de Transição , Doenças do Cão , Neoplasias Hepáticas , Humanos , Cães , Animais , Macrófagos Associados a Tumor , Carcinoma Hepatocelular/veterinária , Carcinoma de Células de Transição/veterinária , Neoplasias Hepáticas/veterinária , Prognóstico , Microambiente Tumoral
4.
New Microbes New Infect ; 35: 100656, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32215211

RESUMO

A 76-year-old Japanese man was admitted to hospital for treatment of fever and skin lesion at the implantation site of his pacemaker. During his hospitalization, vancomycin-intermediate Staphylococcus aureus (MIC 4 µg/mL) with reduced susceptibility to daptomycin was isolated from venous blood. This isolate was identified as methicillin-resistant S. aureus with SCCmec IV and was genotyped as sequence type 81, coa VIIa and spa type t7044, harbouring blaZ, aac(6')-aph(2″) and enterotoxin(-like) genes sea, seb, sek, sel, selx and selw. The patient was successfully treated with daptomycin, minocycline and sulfamethoxazole/trimethoprim. We describe the identification of sequence type 81/SCCmec IV vancomycin-intermediate S. aureus from pacemaker-associated septicaemia.

5.
Science ; 257(5075): 1401-3, 1992 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-1382313

RESUMO

Coronary collateral vessels reduce damage to ischemic myocardium after coronary obstruction. Factors that stimulate collateral formation are expected to have ameliorating effects on myocardial infarction. In a canine experimental myocardial infarct model, intracoronary injection of basic fibroblast growth factor (bFGF) improved cardiac systolic function and reduced infarct size. Treatment with bFGF increased the number of arterioles and capillaries in the infarct. Thus, the angiogenic action of bFGF might lead to a reduction in infarct size. The application of bFGF might bring about a therapeutic modality for the salvage of infarcted myocardium.


Assuntos
Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Animais , Arteríolas/patologia , Capilares/patologia , Divisão Celular , Angiografia Coronária , Vasos Coronários/patologia , Cães , Endotélio Vascular/patologia , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Ventrículos do Coração/patologia , Músculo Liso Vascular/patologia , Infarto do Miocárdio/patologia , Neovascularização Patológica , Tamanho do Órgão
6.
Scand J Rheumatol ; 38(4): 263-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19444719

RESUMO

OBJECTIVE: To determine the association of distinct clinical subsets with myositis-specific autoantibodies (MSAs) towards anti-155/140-kDa polypeptides [anti-155/140 antibodies (Abs)], anti-140-kDa polypeptides (anti-140 Abs), and anti-aminoacyl tRNA synthetases (ARS Abs) in Japanese patients with dermatomyositis (DM). METHODS: We compared the clinical features and short-term prognoses of 30 DM patients whose serological status included these MSAs. The MSAs were determined by immunoprecipitation. RESULTS: Anti-155/140 Abs (n = 5), anti-140 Abs (n = 8), and anti-ARS Abs (n = 7) did not overlap each other. All of the anti-155/140 Ab-positive patients (n = 5) were complicated by malignancies, as were all of the anti-140 Ab-positive patients (n = 8), who showed rapidly progressive interstitial lung disease (ILD). The survival rate at 6 months from the diagnosis of DM was significantly lower in the anti-140 Ab-positive patients than in the other patients. CONCLUSION: This is the first study to report, in a single cohort of DM patients, that distinct clinical subsets are distributed in an anti-155/140 Ab-positive group, an anti-140 Ab-positive group, or an anti-ARS Ab-positive group. Our data also confirm previous evidence that anti-155/140 Abs are involved in malignancies and that anti-140 Abs are involved in rapidly progressive ILD.


Assuntos
Aminoacil-tRNA Sintetases/imunologia , Autoanticorpos/imunologia , Dermatomiosite/diagnóstico , Dermatomiosite/imunologia , RNA de Transferência/imunologia , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Imunoprecipitação , Japão , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Peptídeos/imunologia , Probabilidade , Estatísticas não Paramétricas
7.
Vet J ; 249: 47-52, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31239164

RESUMO

Although antimicrobial peptides (AMPs) play an integral role in the regulation of intestinal microbiota and homeostasis, their expression in canine gastrointestinal diseases, including idiopathic inflammatory bowel disease (IBD) and intestinal lymphoma, remains unknown. The objective of this study was to investigate the intestinal expression of AMPs in dogs with IBD or intestinal lymphoma. IBD was diagnosed in 44 dogs, small cell intestinal lymphoma in 25 dogs, and large cell intestinal lymphoma in 19 dogs. Twenty healthy beagles were used as normal controls. Duodenal mRNA expression of six representative AMPs - lactoferrin, lysozyme, cathelicidin, secretory leukocyte peptidase inhibitor (SLPI), bactericidal/permeability increasing protein (BPI), and canine beta defensin (CBD103) - was quantified by real-time reverse transcription polymerase chain reaction. The relative expression of BPI, lactoferrin, and SLPI was significantly higher in dogs with IBD and intestinal lymphomas than in healthy controls. Interestingly, the expression patterns of AMPs differed between dogs with IBD and those with intestinal lymphomas, especially small cell lymphoma. Increased expression of BPI differentiated IBD from dogs with small cell intestinal lymphoma, with a sensitivity of 93.2%, a specificity of 100%, and an area under the curve of 0.955. These results suggest that the expression patterns of AMP aid in the diagnosis of canine IBD and intestinal lymphoma, although it remains uncertain whether the altered AMP expression is the cause or effect of mucosal inflammation.


Assuntos
Anti-Infecciosos/metabolismo , Peptídeos Catiônicos Antimicrobianos/genética , Doenças do Cão/genética , Duodeno/metabolismo , Doenças Inflamatórias Intestinais/veterinária , Neoplasias Intestinais/veterinária , Linfoma/veterinária , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Cães , Feminino , Expressão Gênica , Doenças Inflamatórias Intestinais/genética , Neoplasias Intestinais/genética , Linfoma/genética , Masculino
8.
J Dent Res ; 95(10): 1176-82, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27151915

RESUMO

To elucidate if microglial P2Y12 receptor (P2Y12R) mechanisms are involved in the trigeminal spinal subnucleus caudalis (Vc; also known as the medullary dorsal horn) in intraoral cancer pain, we developed a rat model of tongue cancer pain. Squamous cell carcinoma (SCC) cells were inoculated into the tongue of rats; sham control rats received the vehicle instead. Nociceptive behavior was measured as the head-withdrawal reflex threshold (HWRT) to mechanical or heat stimulation applied to the tongue under light anesthesia. On day 14 after the SCC inoculation, activated microglia and P2Y12R expression were examined immunohistochemically in the Vc. The HWRT was also studied in SCC-inoculated rats with successive intra-cisterna magna (i.c.m.) administration of specific P2Y12R antagonist (MRS2395) or intraperitoneal administration of minocycline, a microglial activation inhibitor. Tongue cancer was histologically verified in SCC-inoculated rats, within which the HWRT to mechanical stimulation of the tongue was significantly decreased, as compared with that of vehicle-inoculated rats, although the HWRT to heat stimulation was not. Microglia was strongly activated on day 14, and the administration of MRS2395 or minocycline reversed associated nocifensive behavior and microglial activation in SCC-inoculated rats for 14 d. The activity of Vc wide dynamic range nociceptive neurons was also recorded electrophysiologically in SCC-inoculated and sham rats. Background activity and noxious mechanically evoked responses of wide dynamic range neurons were significantly increased in SCC-inoculated rats versus sham rats, and background activity and mechanically evoked responses were significantly suppressed following i.c.m. administration of MRS2395 in SCC-inoculated rats as compared with sham. The present findings suggest that SCC inoculation that produces tongue cancer results in strong activation of microglia via P2Y12 signaling in the Vc, in association with increased excitability of Vc nociceptive neurons, reflecting central sensitization and resulting in tongue mechanical allodynia.


Assuntos
Dor do Câncer/metabolismo , Carcinoma de Células Escamosas/metabolismo , Microglia/metabolismo , Neuralgia/metabolismo , Receptores Purinérgicos P2Y12/metabolismo , Neoplasias da Língua/metabolismo , Núcleo Espinal do Trigêmeo/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Imuno-Histoquímica , Masculino , Minociclina/farmacologia , Nociceptores/metabolismo , Ratos , Ratos Endogâmicos F344 , Transdução de Sinais , Valeratos/farmacologia
9.
Genetics ; 123(4): 749-54, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2612894

RESUMO

We have isolated a Paramecium tetraurelia mutant that divides slowly in daily reisolation cultures and repeats short clonal life spans after successive autogamies. Here we show, using breeding analysis, that a recessive mutation is responsible for the low fission rate and that this low rate is closely related to the short clonal life span. We conclude that a single pleiotropic gene controls these traits and have named it jumyo. In an attempt to further characterize the jumyo mutant, we have revealed that it has a culture life span similar to that of the wild-type cells and that, when mass cultured, it can divide as rapidly as wild-type cells. There was strong evidence that the mutant cells excreted into culture medium some substance that promotes their cell division. These findings may not only present supporting evidence for the hypothesis that the cellular life span is genetically programmed but also give a material basis for the study of the controlling mechanism of cell division in relation to the clonal life span.


Assuntos
Paramecium/genética , Animais , Divisão Celular , Genes , Genes Recessivos , Longevidade , Mutação , Paramecium/fisiologia , Fenótipo
10.
J Bone Miner Res ; 15(8): 1477-88, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10934646

RESUMO

Osteoclasts are thought to belong to a macrophage lineage. However, the nature of common precursors of osteoclasts and macrophages remains to be investigated. We have characterized the differentiation potential of mouse bone marrow macrophages into mature osteoclasts. Monocyte macrophage-colony-stimulating factor (M-CSF) stimulated the proliferation of bone marrow macrophages in a dose-dependent manner and these M-CSF-dependent bone marrow macrophage (MDBM) cells efficiently differentiated into the tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts in the presence of soluble RANKL (sRANKL) and M-CSF in the in vitro culture. The macrophage-like cell line TMC16 was established from tsA58 (temperature-sensitive SV40 large T-antigen) transgenic mice in the same manner to the preparation of MDBM cells and also differentiated into mature osteoclasts. During this differentiation in vitro, the morphology of the cells changed from spindle to round and smaller (termed pOC) on day 2 and to multinuclear (termed multinucleated cells [MNCs]) on day 4. The surface expression of macrophage marker CD14 was down-regulated and that of CD43 was up-regulated on pOC, analyzed by flow cytometry. RNA analysis revealed that osteoclast marker genes such as calcitonin receptor (CTR), carbonic anhydrase II (CAII), cathepsin K (cath K), MMP9, and TRAP were strongly expressed in MNCs and weakly in pOC whereas MDBM cells did not express these genes. However, the osteopontin (OPN) gene was strongly expressed in MDBM cells and this expression became weakened after differentiation into pOC. The TMC16 cell line weakly expressed cath K, TRAP, and OPN, suggesting that the TMC16 cell line is immortalized at a stage slightly differentiated from MDBM cells. Furthermore, cell sorting analysis revealed that osteoclast early progenitors in bone marrow cells are preferentially present in the Mac-1- F4/80dull population, which differentiated into MDBM cells (the osteoclast progenitor) expressing Mac-1+ F4/80int, suggesting that M-CSF plays roles of a differentiation factor as well as a growth factor for osteoclast early progenitors. These results showed the transition of morphology, surface markers, and gene expression from the early to mature stage in osteoclast differentiation. We propose three differentiation stages in the osteoclast lineage: the pro-osteoclast (spindle-shaped macrophage cells), the pre-osteoclast (small round mononucleated TRAP-positive cells), and the mature osteoclast (multinucleated TRAP-positive cells) stage.


Assuntos
Macrófagos/citologia , Osteoclastos/citologia , Células-Tronco/citologia , Animais , Biomarcadores , Diferenciação Celular , Linhagem Celular , Membrana Celular/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Osteoclastos/metabolismo , Fenótipo , RNA Mensageiro , Células-Tronco/metabolismo
11.
J Bone Miner Res ; 16(9): 1593-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11547829

RESUMO

Although tumor necrosis factor receptor-associated factor 6 (TRAF6) is required in receptor activator of NF-kappaB-receptor activator of NF-kappaB ligand (RANK-RANKL) signaling for osteoclastogenesis, it has remained unclear whether TRAF6 is crucial in tumor necrosis factor alpha (TNF-alpha)-induced osteoclastogenesis. We examined TRAF6 function in the TNF-alpha-induced osteoclastogenesis by using osteoclast progenitor cells from TRAF6-deficient mice. The results indicated that TNF-alpha did not effectively induce osteoclast differentiation from osteoclast progenitor cells derived from these mice into mature multinucleated osteoclasts, although c-jun N-terminal kinase (JNK) and TNF-alpha activation was observed in osteoclast progenitor cells. Thus, we have provided the first evidence showing that TRAF6 is involved in TNF-alpha-induced osteoclastogenesis.


Assuntos
Osteoblastos/citologia , Osteogênese/fisiologia , Proteínas/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Proteínas/genética , Proteínas/fisiologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Fator 6 Associado a Receptor de TNF , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima
12.
Cell Calcium ; 10(1): 29-35, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2543505

RESUMO

The effects of platelet-derived growth factor (PDGF) on the intracellular free Ca2+ concentration [( Ca2+]i) in chondrocytes were studied with a fluorescent Ca2+ indicator, fura 2, and compared with the effects of PDGF on mitogenesis and proteoglycan synthesis. PDGF evoked phasic and then tonic increase in [Ca2+]i dose-dependently in quiescent cultures of chondrocytes, and it also stimulated both DNA and proteoglycan syntheses dose-dependently similar to somatomedins. Suramin, which inhibits the interaction of PDGF with its receptors, caused dose-dependent inhibition of both the PDGF-evoked increase in [Ca2+]i and stimulation of DNA synthesis by PDGF. However, suramin rather enhanced the proteoglycan synthesis induced by PDGF without affecting the basal level of proteoglycan synthesis directly. These results suggest that [Ca2+]i may be an important signal for the action of PDGF on cell proliferation in chondrocytes, and that the initial signal for proteoglycan synthesis is different from that for DNA synthesis induced by PDGF after the activation of PDGF receptor.


Assuntos
Cálcio/metabolismo , Cartilagem/citologia , Mitose/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteoglicanas/biossíntese , Suramina/farmacologia , Animais , Benzofuranos , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Citofotometria , Fura-2 , Masculino , Fator de Crescimento Derivado de Plaquetas/metabolismo , Coelhos , Receptores de Superfície Celular/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas
13.
Gene ; 144(2): 301-6, 1994 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-8039717

RESUMO

We have cloned a human cDNA fragment for a gene that is expressed primarily in the heart. To explore its biological function, we have isolated full-length cDNA clones of the gene. DNA sequencing of the 2.7-kb cDNA revealed a 2274-bp ORF. Close to the N terminus of the deduced amino acid sequence is a possible ATP-binding domain that has been assembled by a fusion of B- and A-type adenine nucleotide-binding motifs. In the middle of the sequence is a long stretch of alpha-helical residues that could form a coiled-coil. These features imply that this is a sequence encoding a new human motor protein.


Assuntos
Proteínas Musculares/genética , Miocárdio/metabolismo , Transcrição Gênica , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , DNA Complementar , Humanos , Proteínas Mitocondriais , Dados de Sequência Molecular , Proteínas Musculares/metabolismo , Estrutura Secundária de Proteína , Ratos , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
14.
Free Radic Biol Med ; 16(3): 405-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8063204

RESUMO

The protective effects of phenolic antioxidants on linoleic acid hydroperoxide (LOOH)-induced toxicity to cultured human umbilical vein endothelial cells were examined. Our previous results were confirmed that for tocopherol homologs, lipophilicity and the presence of a phenolic hydroxyl group and two alkyl groups at its ortho positions are critical for protection against LOOH-induced cytotoxicity. Probucol and butylated hydroxytoluene (BHT) were more effective than other simple alkylated phenols. It was found that the protective effects of alkylated phenols were depended on by the presence of two alkyl groups; in particular, two tert-butyl groups, at positions ortho to a hydroxyl group and an alkyl group at the para position. Among alpha-tocopherol, 2,2,5,7,8-pentamethylchroman-6-ol, and BHT, the relative effectiveness of protection against the cytotoxicity (1.0:0.86:0.58, respectively) was inconsistent with the previously reported, relative antioxidant activity in homogeneous solution (1.0:1.2:0.004, respectively). Probably, the effectiveness of protection by phenolic antioxidants against the cytotoxicity depend primarily on their incorporation rate into cells due to their lipophilicity, secondly on their antioxidant activity, and thirdly on their orientation in biomembranes.


Assuntos
Antioxidantes/farmacologia , Ácidos Linoleicos/antagonistas & inibidores , Ácidos Linoleicos/toxicidade , Peróxidos Lipídicos/antagonistas & inibidores , Peróxidos Lipídicos/toxicidade , Fenóis/farmacologia , Antioxidantes/química , Hidroxitolueno Butilado/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromanos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/lesões , Radicais Livres , Humanos , Fenóis/química , Probucol/farmacologia , Relação Estrutura-Atividade , Vitamina E/farmacologia
15.
FEBS Lett ; 348(3): 273-7, 1994 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-8034053

RESUMO

When the expression levels of nucleoside diphosphate (NDP) kinase/nm23 were examined in four human normal diploid fibroblast cell lines in comparison with their corresponding immortalized cells transformed by SV40 large T antigen or 60Co irradiation, mRNA levels of the two isoforms (NDP kinase A/nm23-H1, NDP kinase B/nm23-H2) were increased in the immortalized cell lines. The increase was found to be associated with increased translation products. Furthermore, the cell extracts prepared from these immortalized cell lines demonstrated slightly higher enzyme activity than those from their normal counterparts. Neither the growth state nor the in vitro aging largely affected their expression in a normal cell line (TIG-3) examined. The results suggest possible involvement of NDP kinases/nm23 in acquiring an infinite growth property of these cells.


Assuntos
Antígenos Transformantes de Poliomavirus , Transformação Celular Neoplásica , Radioisótopos de Cobalto , Fibroblastos/metabolismo , Expressão Gênica , Proteínas Monoméricas de Ligação ao GTP , Núcleosídeo-Difosfato Quinase , Fatores de Transcrição/genética , Linhagem Celular Transformada , Diploide , Fibroblastos/efeitos da radiação , Humanos , Nucleosídeo NM23 Difosfato Quinases , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
16.
FEBS Lett ; 160(1-2): 21-4, 1983 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-6350042

RESUMO

We have succeeded in growing Saccharomyces cerevisiae (baker's yeast) on media containing 2H2O and isolating the core histones highly deuterated in the non-exchangeable positions. The deuterated histones obtained here are of great value for their possible widespread use for structural studies of chromatin.


Assuntos
Histonas/isolamento & purificação , Saccharomyces cerevisiae/genética , Deutério , Eletroforese em Gel de Poliacrilamida/métodos , Histonas/genética , Marcação por Isótopo/métodos , Cinética , Saccharomyces cerevisiae/crescimento & desenvolvimento
17.
Mech Ageing Dev ; 22(2): 129-33, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6605462

RESUMO

Epidermal growth factor (EGF) in culture medium increased the saturation density of human diploid fibroblasts. In the first half of their in vitro lifespan the magnitude of the EGF-induced augmentation increased and in the second half, decreased. Their lifespan was not extended by continuous exposure to EGF.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Pulmão/citologia
18.
Mech Ageing Dev ; 13(3): 219-25, 1980 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7421300

RESUMO

Human diploid fibroblasts, TIG-1, were serially subcultivated at low inoculation densities thus maintaining the cultures in log phase throughout their in vitro lifespan. Their lifespan was shortened in calendar time without decreasing the cumulative number of population doublings when compared with the lifespan of cells serially cultivated by a standard method of 1:4 splitting. The cytokinetic and morphological changes during their lifespan are quite similar to those of control cells. The frequency of trypsinization doess not influence the cumulative number of population doublings. The "low-denstiy inoculation method" of subcultivation is efficiently and economically advantageous in studying cellular ageing in vitro.


Assuntos
Sobrevivência Celular , Células Cultivadas , Fibroblastos/fisiologia , Divisão Celular , Fibroblastos/citologia , Humanos , Cinética , Pulmão , Métodos , Modelos Biológicos , Tripsina
19.
Mech Ageing Dev ; 8(4): 233-9, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-703398

RESUMO

The cell lines of chick embryo fibroblasts obtained from different embryos were sequentially cultivated and relationship between growth potential and increased multinuclear cells was examined. During ageing in vitro multinuclear cells increased with decreasing growth rate. Their percentage in the senescent cell populations reached 11--15% when the cells stopped growing, and 20--25% just before the cultures died out. This phenomenon may be useful as a parameter for cellular ageing. Most of the multinuclear cells were binucleates. The mean cell volume of the cells also increased through their lifespan with a sharp rise at the latest passages.


Assuntos
Envelhecimento , Divisão Celular , Embrião de Galinha/fisiologia , Animais , Linhagem Celular , Nucléolo Celular , Embrião de Galinha/crescimento & desenvolvimento , Técnicas In Vitro
20.
Mech Ageing Dev ; 81(1): 27-36, 1995 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-7475350

RESUMO

Nitric oxide synthase (NOS) activity was enhanced in human umbilical vein endothelial cells (HUVECs) by the combined stimulation with IFN-gamma plus IL-1beta, TNF-alpha and LPS which was accompanied by cell death. DNA analysis of the NOS induced dead HUVECs showed that internucleosomal DNA fragmentation had occurred, suggesting that apoptosis was taken place. The enhanced NO production seemed to be associated with the death of HUVECs, however, both NG-methyl-L-arginine (L-NMMA) and nitro-L-arginine (N-arg), inhibitors of NOS, recovered the death of HUVECs by only 16%, suggesting that NO production was minimally involved in the cytokine induced apoptosis of HUVECs. Additional results demonstrated that both the induction of NOS activity and apoptosis in HUVECs declined with in vitro aging, i.e. declined with increasing PDLs of HUVECs, which may explain the decreased immunity during inflammation in aged people.


Assuntos
Envelhecimento/metabolismo , Apoptose/efeitos dos fármacos , Citocinas/farmacologia , Endotélio Vascular/efeitos dos fármacos , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico/fisiologia , Envelhecimento/patologia , Análise de Variância , Células Cultivadas , Citocinas/toxicidade , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Ativação Enzimática , Humanos
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