RESUMEN
Stress fractures of the proximal phalanx of the great toe are primarily attributed to repetitive shear forces, with the vertical ground reaction forces exerting several times the body weight. In the initial stages of injury, conservative management anticipates bone healing within approximately five weeks, followed by a gradual return to sports activities over an additional five weeks. Athletes presenting with pain in this region warrant a thorough evaluation for stress fractures to initiate timely conservative care. In instances of delayed healing or non-union, surgical intervention is indicated. However, literature on the management and optimal timing of surgery, particularly in adolescent athletes, remains sparse. This case report, complemented by a literature review, offers insights into management based on the patient's clinical course.
RESUMEN
BACKGROUND: Coordinated movement in social animal groups via social learning facilitates foraging activity. Few studies have examined the behavioral cause-and-effect between group members that mediates this social learning. METHODOLOGY/PRINCIPAL FINDINGS: We first established a behavioral paradigm for visual food learning using medaka fish and demonstrated that a single fish can learn to associate a visual cue with a food reward. Grouped medaka fish (6 fish) learn to respond to the visual cue more rapidly than a single fish, indicating that medaka fish undergo social learning. We then established a data-mining method based on Kullback-Leibler divergence (KLD) to search for candidate behaviors that induce alignment and found that high-speed movement of a focal fish tended to induce alignment of the other members locally and transiently under free-swimming conditions without presentation of a visual cue. The high-speed movement of the informed and trained fish during visual cue presentation appeared to facilitate the alignment of naïve fish in response to some visual cues, thereby mediating social learning. Compared with naïve fish, the informed fish had a higher tendency to induce alignment of other naïve fish under free-swimming conditions without visual cue presentation, suggesting the involvement of individual recognition in social learning. CONCLUSIONS/SIGNIFICANCE: Behavioral cause-and-effect studies of the high-speed movement between fish group members will contribute to our understanding of the dynamics of social behaviors. The data-mining method used in the present study is a powerful method to search for candidates factors associated with inter-individual interactions using a dataset for time-series coordinate data of individuals.
Asunto(s)
Minería de Datos/métodos , Oryzias/fisiología , Algoritmos , Animales , Condicionamiento Clásico , Conducta Alimentaria , Femenino , Estimulación Luminosa , Reconocimiento en Psicología , Conducta Social , NataciónRESUMEN
Multinuclear alkylene zinc (MAZ) compounds of the type EtZn-(Râ³-Zn)n-Et (Râ³ = ethyl and propyl branched alkylene groups) were synthesized by a simple one-step procedure in nonpolar hydrocarbon solvents from α,ω-dienes (e.g., 1,7-octadiene or 1,9-decadiene) and diethylzinc using a bis(salicylaldiminato)Zr(IV) complex, [(2-methylcyclohexyl)NâCH(2-O-C6H3-3,5-di-tert-butyl)]2ZrMe2, as a catalyst. The MAZ serves as a divalent reversible chain-transfer agent for olefin polymerization, resulting in telechelic Zn-metalated polyolefins whose molecular weights are controllable over a wide range. The Zn-terminated telechelics serve as a polymer precursor for further reactions and can be converted into a variety of telechelic functionalized polyolefins in high yield.
RESUMEN
Peptide arrays in which peptides were immobilized on cellulose membranes through photolinkers were synthesized. The peptides were subsequently detached from the arrays by ultraviolet (UV) photolysis for 3 h, and were used to search for functional peptides that inhibit the activity of α-amylase derived from human pancreatic juice. Amino acid replacement with high-molecular-size amino acids, Arg (R), Phe (F), Trp (W), or Tyr (Y), for the first and seventh residues of amylase inhibitor peptide, GHWYYRCW, as previous reported, led to enhancement of the inhibitory effect of the peptide on α-amylase. In particular, one of the resulting peptides, RHWYYRYW, showed a stronger inhibitory effect than acarbose (which is used as a hypoglycemic agent) or inhibitor peptide GHWYYRCW.
Asunto(s)
Jugo Pancreático/química , Péptidos/síntesis química , alfa-Amilasas/química , Secuencia de Aminoácidos , Aminoácidos/química , Aminoácidos/metabolismo , Sitios de Unión , Celulosa/química , Humanos , Proteínas Inmovilizadas/antagonistas & inhibidores , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Peso Molecular , Péptidos/metabolismo , Fotólisis , Análisis por Matrices de Proteínas , Unión Proteica , Rayos Ultravioleta , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismoRESUMEN
Four methods of cell cycle synchronization of porcine preadipocytes for use as nuclear donors in somatic cell cloning were compared: serum starvation, differentiation induction, contact inhibition and roscovitine treatment. After three days of differentiation induction, the percentage of nuclear donor cells synchronized at the G0/G1 phase reached a peak value of 91.8%, which was significantly higher (P<0.05) than the percentage attained by serum starvation (84.9-89.8%), contact inhibition (78.3-83.7%) or roscovitine treatment (67.8-80.3%). Cell cycle synchronization by serum starvation, contact inhibition and roscovitine treatment all increased the percentage of apoptotic cells, while no increase was observed when the donor-cell cycle was synchronized by differentiation induction (Annexin V-positive: 15.7% to 19.3% vs. 7.7%, P<0.05; TUNEL-positive: 12.8% to 14.0% vs. 8.3%, P<0.05). Additionally, comparison of the in vitro development of nuclear transfer (NT) embryos formed from the nuclei of differentiation-induced or serum-starved preadipocytes revealed that, in both cases, a high proportion of embryos developed to the blastocyst stage (39.0 and 33.7%, respectively). In this study, NT embryos reconstructed with preadipocytes synchronized by differentiation induction were transferred to four recipient pigs, three of which gave birth to a total of 17 piglets (4.2%, 17/403). These results demonstrate that donor-cell cycle synchronization by differentiation induction enables effective production of cloned pigs. The findings also indicate that differentiation induction of multipotent cells is an excellent method of cell cycle synchronization that permits highly efficient synchronization of cells at the G0/G1 phase.
Asunto(s)
Adipocitos/fisiología , Ciclo Celular/fisiología , Clonación de Organismos/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Porcinos/fisiología , Animales , Animales Recién Nacidos , Diferenciación Celular/fisiología , Clonación de Organismos/métodos , Femenino , Repeticiones de Microsatélite/genética , Embarazo , Porcinos/genéticaRESUMEN
Prosaposin triggers G-protein-coupled receptor (GPCR)-mediated protein kinase B (Akt)/extracellular signal-regulated kinase (ERK) phosphorylation cascades to exert its neurotrophic and myelinotrophic activity capable of preventing neural cell death and promoting neural proliferation and glial differentiation. In the present study, we investigated the down-stream neurotrophic signaling mechanism of prosaposin by which rat pheochromocytoma (PC-12) cells are protected from cell death induced by oxidative stress. When PC-12 cells were exposed to H2O2, the cells underwent abrupt shrinkage followed by apoptosis. Prosaposin treatment at as low as 1 nM protected PC-12 cells from cell death by the oxidative stress with the activation of an ERK phosphorylation cascade. Simultaneously, prosaposin blocked the oxidative stress induced-Akt phosphorylation that acts on the down-stream of caspase-3 activation. A MEK inhibitor, PD98059, or a phosphatidylinositol 3-kinase (PI3K) inhibitor, LY294002, abolished the survival effect of prosaposin on the oxidative stress-induced cell death. Furthermore, prosaposin blocked the oxidative stress-induced phosphorylations of c-Jun N-terminal kinase (JNK) and p38 stress-activated protein kinase. We further investigated the effect of prosaposin treatment on the phosphorylation of activating protein-1 (AP-1) complex components, c-Jun and activating transcription factor (ATF)-3. Western blot analysis demonstrated that prosaposin treatment at 100 ng/ml decreased the levels of c-Jun and ATF-3 induced by H2O2 stimulation. Our results suggest that prosaposin aids survival of PC-12 cells from oxidative stress not only by reducing the phosphorylation levels of JNK and p38, but also by regulating the c-Jun/AP-1 pathway.
Asunto(s)
Factor de Transcripción Activador 3/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Factores de Crecimiento Nervioso/fisiología , Estrés Oxidativo , Saposinas/fisiología , Animales , Caspasa 3/fisiología , Muerte Celular/fisiología , Supervivencia Celular/fisiología , Dimerización , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Peróxido de Hidrógeno/farmacología , Oxidantes/farmacología , Células PC12 , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Transducción de Señal , Factor de Transcripción AP-1/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Lipopolysaccharide (LPS) and inflammatory cytokines cause activation of sphingomyelinases (SMases) and subsequent hydrolysis of sphingomyelin (SM) to produce a lipid messenger ceramide. The use of SMase inhibitors may offer new therapies for the treatment of the LPS- and cytokines-related inflammatory bowel disease (IBD). We synthesized a series of difluoromethylene analogues of SM (SMAs). Here, we show that LPS efficiently increases the release of IL-8 from HT-29 intestinal epithelial cells by activating both neutral SMase and nuclear factor (NF)-kappaB in the cells. The addition of SMA-7 suppressed neutral SMase-catalyzed ceramide production, NF-kappaB activation, and IL-8 release from HT-29 cells caused by LPS. The results suggest that activation of neutral SMase is an underlying mechanism of LPS-induced release of IL-8 from the intestinal epithelial cells. Ceramide production following LPS-induced SM hydrolysis may trigger the activation of NF-kappaB in nuclei. Oral administration of SMA-7 (60 mg/kg) to mice with 2% dextran sulfate sodium (DSS) in their drinking water, for 21 consecutive days, reduced significantly the severity of colonic injury. This finding suggests a central role for SMase/ceramide signaling in the pathology of DSS-induced colitis in mice. The therapeutic effect of SMA-7 observed in mice may involve the suppression of IL-8 production from intestinal epithelial cells by LPS or other inflammatory cytokines.
Asunto(s)
Colitis/tratamiento farmacológico , Interleucina-8/metabolismo , Mucosa Intestinal/inmunología , Lipopolisacáridos/farmacología , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Esfingomielinas/farmacología , Esfingomielinas/uso terapéutico , Enfermedad Aguda , Administración Oral , Animales , Línea Celular , Ceramidas/metabolismo , Colitis/inducido químicamente , Sulfato de Dextran/efectos adversos , Interleucina-8/antagonistas & inhibidores , Mucosa Intestinal/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Esfingomielinas/administración & dosificación , Esfingomielinas/químicaRESUMEN
Lipopolysaccharide (LPS) and inflammatory cytokines cause activation of sphingomyelinases (SMases) and subsequent hydrolysis of sphingomyelin (SM) to produce a lipid messenger ceramide. The design of SMase inhibitors may offer new therapies for the treatment of LPS- and cytokine-related inflammatory bowel disease. We synthesized a series of difluoromethylene analogues of SM (SMAs). We report here the effects of the most potent SMase inhibitor, SMA-7, on the LPS-mediated release of tumour necrosis factor-alpha, interleukin-1beta and interleukin-6 from THP-1 macrophages and the pathology of dextran sulphate sodium (DSS)-induced colitis in mice. SMA-7 suppressed the LPS-induced cytokine release and nuclear factor-kappaB activation. LPS stimulation caused a four-fold increase in acid SMase activation, but little increase in neutral SMase activity. The presence of 10 microm SMA-7 caused acid SMase to remain at the control levels and reduced the formation of ceramide. HT-29 cells had significantly decreased cell viability when incubated with media from LPS-stimulated THP-1 macrophages. However, incubating the colon cells in media from both SMA-7 and LPS-treated macrophages caused little decrease in viability, suggesting that ceramide has a role in the LPS-stimulated signalling that releases cytotoxic factors against colon cells. Oral administration of SMA-7 to mice with 2% DSS in the drinking water, for 10 or 21 consecutive days, reduced significantly the cytokine levels in the colon and the severity of colonic injury. These findings suggest a central role for acid SMase/ceramide signalling in the pathology of DSS-induced colitis in mice, indicating a possible preventive or therapeutic role for SMase inhibitor in inflammatory bowel disease.
Asunto(s)
Citocinas/metabolismo , Enfermedades Inflamatorias del Intestino/prevención & control , Lipopolisacáridos/inmunología , Macrófagos/inmunología , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Sulfato de Dextran , Modelos Animales de Enfermedad , Mediadores de Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/patología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Masculino , Ratones , Ratones Endogámicos BALB C , Inhibidores de Fosfodiesterasa/farmacología , Inhibidores de Fosfodiesterasa/uso terapéutico , Esfingomielina Fosfodiesterasa/metabolismo , Esfingomielina Fosfodiesterasa/fisiología , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Crocus sativus L. (saffron) has been used as a spice for flavoring and coloring food preparations, and in Chinese traditional medicine as an anodyne or tranquilizer. Our previous study demonstrated that crocin, a carotenoid pigment of saffron, can suppress the serum deprivation-induced death of PC12 cells by increasing glutathione (GSH) synthesis and thus inhibiting neutral sphingomyelinase (nSMase) activity and ceramide formation. The carotenoid pigments of saffron consist of crocetin di-(beta-d-glucosyl)-ester [dicrocin], crocetin-(beta-d-gentiobiosyl)-(beta-d-glucosyl)-ester [tricrocin] and crocetin-di-(beta-d-gentiobiosyl)-ester [crocin]. Saffron also contains picrocrocin, the substance causing saffron's bitter taste. In this study, to confirm whether neuroprotective effects of saffron are caused solely by crocin, we examined the antioxidant and GSH-synthetic activities of these crocins in PC12 cells under serum-free and hypoxic conditions. Measurements of cell viability, peroxidized membrane lipids and caspase-3 activity showed that the rank order of the neuroprotective potency at a concentration of 10 muM was crocin>tricrocin>dicrocin and picrocrocin (the latter two crocins had a little or no potency). In addition, we show that among these saffron's constituents, crocin most effectively promotes mRNA expression of gamma-glutamylcysteinyl synthase (gamma-GCS), which contributes to GSH synthesis as the rate-limiting enzyme, and that the carotenoid can significantly reduce infarcted areas caused by occlusion of the middle cerebral artery (MCA) in mice.
Asunto(s)
Antioxidantes/farmacología , Infarto Encefálico/prevención & control , Carotenoides/farmacología , Crocus , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Infarto Encefálico/etiología , Infarto Encefálico/patología , Carotenoides/química , Carotenoides/aislamiento & purificación , Caspasa 3/metabolismo , Hipoxia de la Célula , Supervivencia Celular/efectos de los fármacos , Crocus/química , Ciclohexenos/farmacología , Modelos Animales de Enfermedad , Glucósidos/farmacología , Glutamato-Cisteína Ligasa/metabolismo , Glutatión/biosíntesis , Infarto de la Arteria Cerebral Media/complicaciones , Peroxidación de Lípido/efectos de los fármacos , Masculino , Lípidos de la Membrana/metabolismo , Ratones , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Células PC12 , Ratas , Relación Estructura-Actividad , Terpenos/farmacología , Factores de Tiempo , Vitamina A/análogos & derivadosRESUMEN
The objective of this study is to evaluate the cost-effectiveness of letrozole compared with tamoxifen as first-line therapy in post-menopausal women with advanced breast cancer in Japan. A Markov analytical model was developed to estimate life-year (LY) expectancies, using key transition probabilities obtained from the results of a multinational phase III trial, a literature review and a Japanese medical expert panel. Direct medical costs were estimated, from the payer's perspective, using the expected resource utilization provided by the expert panel, the medical fee table and drug tariff under the national health insurance system. The expected overall life-years (LYs) obtained were 3.68 years for letrozole arm and 3.09 years for tamoxifen arm, showing incremental LYs of 0.59 years in patients receiving letrozole. The total expected costs were 3,644,588 yen (33,133 US dollars) for letrozole arm and 3,322,111 yen (30,201 US dollars) for tamoxifen arm, resulting in a mean incremental cost-effectiveness ratio (ICER) of 546,571 yen (4,969 US dollars) per life-year gained, while the 5 th percentile of ICER showed letrozole dominating tamoxifen and the 95th percentile was 2,310,593 yen (21,005 US dollars). The results suggest that letrozole is a clinically beneficial and cost-effective treatment option when compared with tamoxifen in first-line therapy for advanced breast cancer in Japan.
Asunto(s)
Antineoplásicos Hormonales/economía , Neoplasias de la Mama/tratamiento farmacológico , Nitrilos/economía , Posmenopausia , Tamoxifeno/economía , Triazoles/economía , Anciano , Antineoplásicos Hormonales/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/economía , Neoplasias de la Mama/economía , Análisis Costo-Beneficio , Esquema de Medicación , Femenino , Humanos , Letrozol , Persona de Mediana Edad , Programas Nacionales de Salud/economía , Nitrilos/administración & dosificación , Años de Vida Ajustados por Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Tamoxifeno/administración & dosificación , Triazoles/administración & dosificaciónRESUMEN
The aim of the present study was to determine whether porcine preadipocytes can be efficient donor cells for somatic cell nuclear transfer (SCNT) in pigs. Primary culture of porcine preadipocytes was established by de-differentiating mature fat cells taken from an adult pig. The cell cycle of the preadipocytes could be synchronized by serum starvation for 1 day, with a higher efficiency than control fetal fibroblasts. Incidence of premature chromosome condensation following nuclear transfer (NT) of preadipocytes was as high as that observed after NT with fetal fibroblasts. In vitro developmental rate of the NT embryos reconstructed with preadipocyte was equivalent to that of the fetal fibroblast derived embryos. Transfer of 732 NT embryos with preadipocytes to five recipients gave rise to five cloned piglets. These data demonstrate that preadipocyites collected from an adult pig are promising nuclear donor cells for pig cloning.
Asunto(s)
Adipocitos/fisiología , Clonación de Organismos , Técnicas de Transferencia Nuclear , Porcinos , Adipocitos/citología , Animales , Diferenciación Celular , Clonación de Organismos/métodos , Transferencia de Embrión , Femenino , Feto/citología , Feto/fisiología , Fibroblastos/citología , Fibroblastos/fisiología , Embarazo , Porcinos/fisiologíaRESUMEN
A 63-year-old man, who had been operated with right hemicolectomy 1 year and 3 months ago, had giant liver metastasis, lung metastasis, and local dissemination tumor due to ascending colon cancer. He was treated by systemic chemotherapy with 5-FU and the treatment evaluation was PD on CT. After admission to our hospital, he was treated by hepatic arterial infusion chemotherapy with CDDP, CPT-11, and 5-FU. After 3 courses of the treatment, each recurrent lesion decreased on CT and the CEA level decreased. There were no side effects except mild diarrhea. We believe hepatic arterial infusion chemotherapy with CDDP, CPT-11, and 5-FU may be an effective strategy against liver metastasis and extrahepatic metastsis due to colon cancer.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Camptotecina/análogos & derivados , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Antimetabolitos Antineoplásicos/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Camptotecina/administración & dosificación , Cisplatino/administración & dosificación , Neoplasias del Colon/patología , Fluorouracilo/administración & dosificación , Arteria Hepática , Humanos , Infusiones Intraarteriales , Irinotecán , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/secundarioRESUMEN
Magnesium-dependent neutral sphingomyelinase (N-SMase) present in plasma membranes is an enzyme that can be activated by stress in the form of inflammatory cytokines, serum deprivation, and hypoxia. The design of small molecule N-SMase inhibitors may offer new therapies for the treatment of inflammation, ischemic injury, and cerebral infarction. Recently, we synthesized a series of difluoromethylene analogues (SMAs) of sphingomyelin. We report here the effects of SMAs on the serum/glucose deprivation-induced death of neuronally differentiated pheochromocytoma (PC-12) cells and on cerebral infarction in mice. SMAs inhibited the enhanced N-SMase activity in the serum/glucose-deprived PC-12 cells, and thereby suppressed the apoptotic sequence: ceramide formation, c-Jun N-terminal kinase phosphorylation, caspase-3 activation, and DNA fragmentation in the nuclei. Administration of SMA-7 (10 mg/kg i.v.) with IC50= 3.3 microM to mice whose middle cerebral arteries were occluded reduced significantly the size of the cerebral infarcts, compared to the control mice. These results suggest that N-SMase is a key component of the signaling pathways in cytokine- and other stress-induced cellular responses, and that inhibiting or stopping N-SMase activity is an important strategy to prevent neuron death from ischemia.
Asunto(s)
Isquemia Encefálica/patología , Inhibidores Enzimáticos/farmacología , Neuronas/enzimología , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Animales , Western Blotting , Caspasa 3 , Caspasas/metabolismo , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ceramidas/biosíntesis , ADN/análisis , ADN/biosíntesis , Fragmentación del ADN , Electroforesis en Gel de Poliacrilamida , Glucosa/deficiencia , Indicadores y Reactivos , Infarto de la Arteria Cerebral Media/patología , Proteínas Quinasas JNK Activadas por Mitógenos , Masculino , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neuronas/efectos de los fármacos , Células PC12 , Fosforilación , RatasRESUMEN
Crocin is a pharmacologically active component of Crocus sativus L. (saffron) used in traditional Chinese medicine. We report here the effects of crocin on neuronally differentiated pheochromocytoma (PC-12) cells deprived of serum/glucose. Depriving the PC-12 cells of serum/glucose caused peroxidation of their cell membrane lipids and decreased intercellular superoxide dismutase (SOD) activity. Treating the PC-12 cells with 10 microM crocin inhibited the formation of peroxidized lipids, partly restored the SOD activity, and maintained the neuron's morphology. These antioxidant effects of crocin were more effective than those of alpha-tocopherol at the same concentration. Crocin also suppressed the activation of caspase-8 caused by serum/glucose deprivation. These results together with our previous data suggest that crocin is a unique and potent antioxidant that combats oxidative stress in neurons.
Asunto(s)
Antioxidantes/farmacología , Carotenoides/farmacología , alfa-Tocoferol/farmacología , Animales , Antioxidantes/química , Carotenoides/química , Caspasas/metabolismo , Muerte Celular/fisiología , Relación Dosis-Respuesta a Droga , Células PC12 , Ratas , alfa-Tocoferol/químicaRESUMEN
Plasminogen activator inhibitor-1 is a serpin that regulates the activities of plasminogen activators. However, its physiological roles in the CNS are incompletely understood. We have found that plasminogen activator inhibitor-1 has a novel biological function in the CNS: the contribution to survival of neurites on neurons. PC-12 cells treated with nerve growth factor differentiated into neurons and formed a network of neurites. In a serum-free culture medium, these neurites disappeared within 24 h. The addition of plasminogen activator inhibitor-1 prevented the disintegration of the neuronal networks, while the addition of the serpin inhibitors aprotinin and antipain did not. The plasminogen activator inhibitor-1 maintained or promoted the phosphorylated state of extracellular signal-regulated kinase (ERK), but not of protein kinase B (Akt). These results are the first evidence that plasminogen activator inhibitor-1 in the CNS acts to maintain the morphology of neurites via activation of the ERK-related pathway in the neurons.
Asunto(s)
Neuritas/efectos de los fármacos , Neuronas/efectos de los fármacos , Inhibidor 1 de Activador Plasminogénico/farmacología , Inhibidores de Serina Proteinasa/farmacología , Animales , Western Blotting/métodos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Interleucina-6/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Factor de Crecimiento Nervioso/farmacología , Células PC12 , Feocromocitoma , Fosforilación/efectos de los fármacos , Ratas , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Crocin is a pharmacologically active component of Crocus sativus L. (saffron) that has been used in traditional Chinese medicine. In a previous study, we demonstrated that crocin inhibits apoptosis in PC-12 cells by affecting the function of tumor necrosis factor-alpha. In this study, we found that depriving cultured PC-12 cells of serum/glucose causes a rapid increase in cellular ceramide levels, followed by an increase in the phosphorylation of c-jun kinase (JNK). The accumulation of ceramide was found to depend on the activation of magnesium-dependent neutral sphingomyelinase (N-SMase), but not on de novo synthesis. The serum/glucose-deprived PC-12 cells also decreased the cellular levels of glutathione (GSH), which is the potent inhibitor of N-SMase. Treating the PC-12 cells with crocin prevented N-SMase activation, ceramide production, and JNK phosphorylation. We also found that the chemical can enhance the activities of GSH reductase and gamma-glutamylcysteinyl synthase (gamma-GCS), contributing to a stable GSH supply that blocks the activation of N-SMase. Thus our data suggest that crocin combats the serum/glucose deprivation-induced ceramide formation in PC-12 cells by increasing GSH levels and prevents the activation of JNK pathway, which is reported to have a role of the signaling cascade downstream ceramide for neuronal cell death.
Asunto(s)
Carotenoides/farmacología , Ceramidas/fisiología , Glutatión/biosíntesis , Transducción de Señal/efectos de los fármacos , Esfingomielina Fosfodiesterasa/fisiología , Aminoaciltransferasas/biosíntesis , Aminoaciltransferasas/genética , Animales , Western Blotting , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ceramidas/metabolismo , Medio de Cultivo Libre de Suero , Glucosa/fisiología , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Indicadores y Reactivos , Proteínas Quinasas JNK Activadas por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/fisiología , Células PC12 , Fosforilación , ARN Mensajero/biosíntesis , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esfingomielina Fosfodiesterasa/metabolismoRESUMEN
The patient was a 49-year-old woman who had locally advanced breast cancer with skin invasion. She was placed on neoadjuvant weekly systemic chemotherapy of TXL (65 mg/m2) and ADM (20 mg/m2). After systemic chemotherapy, she underwent 2 courses of transarterial neoadjuvant chemotherapy of TXL (day 1, 8, 15). We administered TXL (45 mg/m2) into the subclavian artery and TXL (20 mg/m2) into the internal thoracic artery. Although she experienced grade 3 leukopenia during systemic chemotherapy, she experienced only grade 2 alopecia and grade 1 nausea during transarterial chemotherapy. After chemotherapy, she underwent radical mastectomy. We report herein a case in which transarterial neoadjuvant chemotherapy with TXL was effective.
Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Paclitaxel/administración & dosificación , Neoplasias de la Mama/cirugía , Doxorrubicina/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Infusiones Intraarteriales , Mastectomía Radical , Persona de Mediana Edad , Terapia Neoadyuvante , Arteria Subclavia , Arterias TorácicasRESUMEN
This paper methodologically compares the electro-fusion (EF) and intracytoplasmic injection (ICI) methods, as well as simultaneous fusion/activation (SA) and delayed activation (DA), in somatic nuclear transfer in pigs using fetal fibroblast cells. Comparison of the remodeling pattern of donor nuclei after nuclear transfer by ICI or EF showed that a high rate (80-100%) of premature chromosome condensation occurred in both cases whether or not Ca2+ was present in the fusion medium. Formation of pseudo-pronuclei tended to be lower for nuclear transfer performed by the ICI method (65% vs. 85-97%, p < 0.05). In vitro developmental potential of nuclear transfer embryos reconstructed with IVM oocytes using the EF method was higher than that of those produced by the ICI method (blastocyst formation: 19 vs. 5%, p < 0.05), and it was not improved using in vivo-matured oocytes as recipient cytoplasts. Embryos produced using SA protocol developed to blastocysts with the same degree of efficiency as those produced under the DA protocol (11 vs. 12%). Use of the EF method in conjunction with SA was shown to be an efficient method for producing cloned pigs based on producing a cloned normal pig fetus. However, subtle differences in nuclear remodeling patterns between the SA and DA protocols may imply variations in their nuclear reprogramming efficiency.
Asunto(s)
Clonación de Organismos/métodos , Electroporación/métodos , Microinyecciones/métodos , Técnicas de Transferencia Nuclear , Porcinos , Animales , Calcio/metabolismo , Fusión Celular , Cromosomas/genética , Citoplasma , Transferencia de Embrión , Femenino , Cariotipificación , Masculino , Oocitos/fisiología , EmbarazoRESUMEN
Plasminogen activator inhibitor-1 (PAI-1) is a serpin that suppresses fibrinolysis by inhibiting the activity of plasminogen activator (PA). Together with PA, PAI-1 is expressed in the central nervous system and may play a role in the regulation of PA activity. Our present study has demonstrated that, in cultures of PC-12 neurons, depletion of PAI-1 from the culture medium induces disappearance of the cell's neurites and the cell death. Aprotinin and antipain, the inhibitors of PA, were not counterparts of PAI-1 in the protection of neurite disappearance. We also found that PAI-1 had the abilities to promote release of the survival factors of neurons, IL-6 and VEGF and activation of a survival serine/threonine kinase Akt. These results suggest that PAI-1 has physiological functions other than its role as PA inhibitor for the survival of neurons.
Asunto(s)
Encéfalo/fisiología , Factores de Crecimiento Nervioso , Inhibidor 1 de Activador Plasminogénico/fisiología , Inhibidores de Serina Proteinasa/fisiología , Animales , Células Cultivadas , Factores de Crecimiento Endotelial/metabolismo , Fibrinólisis/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Interleucina-6/metabolismo , Linfocinas/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Neuritas/efectos de los fármacos , Neuronas/metabolismo , Fosforilación/efectos de los fármacos , Inhibidor 1 de Activador Plasminogénico/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Ratas , Inhibidores de Serina Proteinasa/farmacología , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
Sphingomyelin (SM) pathway, where sphingomyelinase (SMase) hydrolyzes SM to produce ceramide, has recently been suggested to link to the signaling pathway that determines cell death. Therefore, elucidation of the mechanism by which SMase is activated and the regulation of SMase activity will be an important therapeutic strategy for various cytokine-related and ischemic diseases. We have synthesized nine difluoromethylene analogues of SM as SMase inhibitors and evaluated their inhibitory potencies. In this study, we show that the inhibitor suppresses ceramide production and cell death of PC-12 neurons that have been induced by deprivation of serum from the culture medium. The SMase inhibitor could also suppress neuronal cell death in a mouse model of brain ischemia. These results suggest a possibility that the prevention of various extracellular stress-induced cell death signalings is accomplished by inhibiting the cell membrane SMase.