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1.
Zhonghua Yi Xue Za Zhi ; 100(34): 2652-2657, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-32921012

RESUMO

Objective: To analyze the risk factors of postoperative intestinal obstruction (POI) in patients undergoing robot-assisted laparoscopic radical prostatectomy (RARP). Methods: The clinical data of 573 patients receiving RARP from January to December 2019 in Nanjing Drum Tower Hospital were analyzed retrospectively. According to the occurrence of POI, the cases were divided into the occurrence group and the non-occurrence group. The clinical data of the two groups were compared and the risk factors of POI were investigated by multivariate logistic regression. Results: Forty-five of 573 patients (7.9%) had POI. Between the two groups, preoperative underlying diseases (cardiopathy, COPD, hypoalbuminemia), preoperative chemotherapy, preoperative WBC, operation time, blood loss, blood transfusion rate, postoperative early fever, length of stay were statistically significant (P<0.05). Multivariable logistic regression analysis showed that heart disease (OR=2.331, P=0.036), COPD (OR=4.285, P=0.001), hypoalbuminemia(OR=2.142, P=0.026), blood loss (≥4.26 ml/kg) (OR=2.388, P=0.010), operative time (≥225 min) (OR=4.200, P<0.001), and postoperative early fever (OR=2.773, P=0.004) were independent risk factors for POI after RARP. Conclusions: The incidence of POI following RARP is related to multiple perioperative factors. Improving the preoperative heart and lung function, correcting hypoalbuminemia, reducing intraoperative bleeding, shortening the operation time, and preventing early postoperative infection may be important measures to reduce the risk of POI in RARP patients.


Assuntos
Obstrução Intestinal , Laparoscopia , Neoplasias da Próstata/cirurgia , Robótica , Humanos , Masculino , Prostatectomia , Estudos Retrospectivos , Fatores de Risco
2.
J Mater Chem B ; 8(1): 27-37, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31746932

RESUMO

Resveratrol (RES) is a naturally occurring and effective drug for tumor prevention and treatment. However, its low levels of aqueous solubility, stability, and poor bioavailability limit its application, especially when used as a free drug. In this study, RES was loaded into peptide and sucrose liposomes (PSL) to enhance the physico-chemical properties of RES and exploit RES delivery mediated by liposomes to effectively treat breast cancer. RES loaded PSL (the complex: PSL@RES) were stable, had a good RES encapsulation efficiency, and prolonged RES-release in vitro. PSL@RES was exceptionally efficient for inhibiting the growth of cancer cells, as the IC50 of PSL@RES in MCF-7 cells was found to be only 20.89 µmol L-1. The therapeutic efficacy of PSL@RES was evaluated in mice bearing breast cancer. The results showed that PSL@RES at a dosage of 5 mg kg-1 was more effective than 10 mg kg-1 free RES, and PSL@RES inhibited tumor growth completely at a dosage of 10 mg kg-1. PSL@RES induced apoptosis in breast tumor by upregulation of p53 expression. This then downregulated Bcl-2 and upregulated Bax, thereby inducing Caspase-3 activation. More importantly, encapsulation of RES within peptide liposomes greatly reduced the toxicity of free RES to mice. Overall, the simple formulation of liposomal nanocarriers of RES developed in this study produces satisfactory outcomes to encourage further applications of liposomal carriers for the treatment of breast cancer.


Assuntos
Antineoplásicos , Portadores de Fármacos/química , Lipossomos/química , Neoplasias Mamárias Experimentais/tratamento farmacológico , Resveratrol , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Resveratrol/administração & dosagem , Resveratrol/uso terapêutico
3.
Artigo em Chinês | MEDLINE | ID: mdl-31446744

RESUMO

SummaryChronic nasal-sinusitis is a chronic inflammatory disease characterized by persistent inflammation in the nasal and nasal mucosa. The pathogenesis of CRS is extremely complex and there is currently a lack of effective therapy. The reason for inaccurate diagnosis and invalid treatment of CRS is its sophisticated and unclear mechanism. The pathogenesis of CRS from Asian populations is neutrophil infiltration mediated by Th1/Th17 mixture. Consequently, exploring the function of neutrophil in the pathogenesis of CRS plays an important role in clinical diagnosis and treatment for CRS patients in China.


Assuntos
Neutrófilos/citologia , Rinite/imunologia , Sinusite/imunologia , Doença Crônica , Humanos , Mucosa Nasal
4.
Zhonghua Fu Chan Ke Za Zhi ; 54(6): 363-368, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31262119

RESUMO

Objective: To investigate the current status of uterine rupture in pregnant women in China and analyze the impacts of different surgical histories on the pregnancy outcomes of pregnant women with uterine rupture. Methods: The clinical records and pregnancy outcomes of 84 uterine rupture cases were collected and analyzed retrospectively. All cases came from 21 hospitals of 13 provinces (or municipality) in China, dated from January 1st 2014 to December 31st 2015. The total deliveries were 283 614 during the period. For 84 pregnant women with symptomatic uterine rupture, the impacts of different surgical histories on pregnancy outcomes were compared and the results were statistically analyzed. Results: (1) Totally, 84 cases of uterine rupture were with symptoms and diagnosed. The median age, median gestational age were 32.5 years old (23.0-44.0 years old) and 35.7 weeks (9.3-41.0 weeks), respectively. The incidence of uterine rupture was 0.03% (84/283 614). The proportion of patients with cesarean section history was 66.7% (56/84). The proportion of patients with other gynecological surgery history was 20.2% (17/84). (2)Compared with the group of cesarean section history, the group with other gynecological surgery history had a significant increase in complete uterine rupture (16/17 vs 66.1%, P<0.05). Meanwhile, regarding the massive blood transfusion (red blood cell transfusion≥1 000 ml) in the treatment of uterine rupture, patients with other gynecological surgery history had significant more cases than the group with cesarean section history (9/17 vs 23.2%, P<0.05). There was no statistical difference for the other outcomes. Compared with the patients with cesarean section history, the rate of hysterectomy was higher in the group without major surgery history when uterine rupture happened (4/11 vs 7.1%, P<0.05). The incidence of postpartum hemorrhage significantly increased in patients without major surgery history, compared with those with cesarean section (8/11 vs 28.6%, P<0.05). There were no statistic difference for other outcomes. (3) Patients with uterine rupture in the non-abdominal pain group had a significantly increased risk of massive blood transfusion (5/8 vs 27.6%, P<0.05),and the incidence of neonatal asphyxia and hypoxic ischemic encephalopathy (4/7 vs 22.2%, P<0.05) were significantly increased. There were no significant difference between two groups regarding the other outcomes, such as preoperative diagnosis, complete rupture of uterus, hysterectomy, postpartum hemorrhage, shock, intrauterine fetal death or neonatal death, admission to neonatal ICU. Conclusions: In addition to considering cesarean section history as one of the known risk factors, patients with non-cesarean section uterine surgery history should also be considered. The management of these patients should be strengthened during their pregnancy and delivery. There might be much more dangerous maternal and neonatal outcomes for the patients with uterine rupture who does not have any abdominal pain during pregnancy and delivery. To reduce the incidence of severe complications, uterine rupture should be diagnosed earlier. The early recognition and diagnosis of uterine rupture helps to improve maternal and neonatal outcomes.


Assuntos
Cesárea/efeitos adversos , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Ruptura Uterina/diagnóstico , Ruptura Uterina/etiologia , Adulto , China/epidemiologia , Feminino , Humanos , Complicações do Trabalho de Parto/epidemiologia , Complicações do Trabalho de Parto/etiologia , Procedimentos Cirúrgicos Obstétricos , Complicações Pós-Operatórias/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos , Inquéritos e Questionários , Ruptura Uterina/epidemiologia , Adulto Jovem
5.
Zhonghua Fu Chan Ke Za Zhi ; 54(5): 312-317, 2019 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-31154712

RESUMO

Objective: To investigate the acceptance of HPV self-sampling mode in cervical cancer screening population and explore its feasibility. Methods: From March 5 to 15, 2018, researchers investigated women who participated in cervical cancer screening organized by Beijing Shunyi Women's and Children's Hospital in the form of questionnaires. Questionnaires were conducted on their acceptance status and the factors that affect the self-sampling experience. The specific contents of the questionnaires were as follows: (1) the experience of using self-sampling included operability, comfortable, sample time-consuming, bleeding or not after sampling; (2) psychological changes after self-sampling, including the willingness to accept self-sampling again, the worrying problems during self-sampling process. According to whether or not have operating video guidance, the self-sampling experience and psychological changes after self-sampling were compared. Results: (1) There were 1 375 women participated in the questionnaire survey, and 86.55% (1 190/1 375) of them thought the self-sampling was convenient, 78.40% (1 078/1 375) thought it was not uncomfortable, 88.58% (1 218/1 375) thought the sampling time was fast (less than 5 minutes), 94.04% (1 293/1 375) self-sampling without bleeding; and 83.27% (1 145/1 375) were willing to self-sampling for cervical cancer screening again, 85.82% (1 180/1 375) were afraid of inaccurate sampling. (2) Among the 1 375 women, 1 202 were in the video guidance group and 173 were in the non-guidance group. The self-sampling experience of women in video guidance group was better than those of non-guidance group in operability, comfortable, sampling time-consuming and bleeding after sampling. The proportion of women who willing to self-sampling again was higher than that of non-guidance group (86.69% vs 59.54%, respectively). The proportion of women who worried operating incorrectly was lower than that of non-guidance group (11.23% vs 32.37%, respectively). The differences were significant (all P<0.05). Conclusions: Self-sampling for HPV testing in cervical cancer screening is easy to operate and has little discomfort complaint. It is feasible in cervical cancer screening. Operational video guidance during the screening process could effectively improve the women's experience and willingness to self-sampling again in the future.


Assuntos
Programas de Rastreamento , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde , Neoplasias do Colo do Útero/diagnóstico , Adulto , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Autocuidado , Manejo de Espécimes , Inquéritos e Questionários , Esfregaço Vaginal
6.
Zhonghua Fu Chan Ke Za Zhi ; 52(11): 745-750, 2017 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-29179269

RESUMO

Objective: To study the clinical management way for HPV(+)/papanicolaou (Pap)(-) during cervical cancer screening. Methods: To analyze retrospectively the data from the patients who had loop electrical excision procedure (LEEP) for biopsy confirmed cervical intraepithelial neoplasia (CIN) Ⅱ in Peking University People's Hospital from Jan. 2010 to Dec. 2014. Results: (1) For biopsy confirmed CIN Ⅱ, HPV positive rate was 98.5% (135/137), Pap test positive [≥atypical squamous cell of undetermined significance (ASCUS)] rate was 69.3% (95/137), there was significant difference between them (χ(2)=43.32, P<0.01). (2) For the 42 patients with HPV(+)/Pap(-), whose cytology slides were reviewed again. Among them, the interpretations of there were 16 cases confirmed as the same before, while 26 cases were changed to abnormal (≥ASCUS). Cytology be misdiagnosed was 19.0% (26/137) at the first review. Among the 26 cases, 13 (50.0%) cases were missed for the little amount of abnormal cells, 8 (30.8%) cases for mild atypical morphology changed; the other 5 (19.2%) cases missed for stain problems. (3) For the cervical LEEP samples, 37 cases of the pathology diagnosis were upgrade to CIN Ⅲ(+), among them, 2 cases of microinvasive cervical carcinoma, 1 case of invasive cancer, 34 cases of CIN Ⅲ; 37 cases were CINⅠ or no lesion found; 63 cases were still CIN Ⅱ. Four to six months later after LEEP, the cytology abnormal rate was 11.7% (16/137), and the HR-HPV positive rate was 34.3% (47/137). Conclusions: Compared with cytology alone, cytology combined with HPV testing increase the sensitivity of cervical high grade lesion. For the cases of HPV(+)/Pap(-) cases, the cytology slides should be reviewed. The quality control of cervical exfoliate sample collection and interpretation should be strengthened. LEEP procedure is not only a treatment method, but also it could provide samples to confirm the diagnosis.


Assuntos
Teste de Papanicolaou , Papillomaviridae/isolamento & purificação , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal , Adulto , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Manejo de Espécimes , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal/métodos
7.
J Mater Chem B ; 5(39): 7963-7973, 2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32264197

RESUMO

Headgroups in cationic lipids play very important roles in determining transfection efficiency and toxicity in gene delivery. To better understand the influence of headgroups on gene delivery, a tri-peptide-based lipid was synthesized, wherein the usual quaternary ammonium was replaced by a tri-peptide. Though both the tri-peptide-based lipid (DAO3) and the quaternary ammonium-based lipid (DDCTMA) successfully mediated gene transfection, DAO3 was superior to DDCTMA in both in vitro and in vivo studies. Following their preparation into liposomes, the particle size, zeta potential, and DNA-binding capacity of the liposomes and lipoplexes were characterized to evaluate the efficiency of DAO3 compared to DDCTMA with regard to gene interactions. The expression of luciferase from pDNA mediated by DAO3 was 2-fold greater than than that with DDCTMA in Hep-2 cells, and DAO3/siRNA lipoplexes could silence about 60% luciferase in A549 cancer cells expressing firefly luciferase. DAO3/Luc-siRNA treatment exhibited 3-fold the efficiency of DDCTMA/Luc-siRNA in terms of in vivo luciferase RNAi with the bare density ratio of 0.54 at 48 h. Furthermore, DAO3 could mediate IGF-1R siRNA to inhibit tumor growth through silencing the expression of the IGF-1R protein, whereas DDCTMA showed nearly no effects. Most importantly, DAO3 had no obvious toxicity in vitro and in vivo, due to the biocompatibility of the peptide headgroups. In conclusion, these results demonstrated that the replacement of the quaternary ammonium headgroup by tri-ornithine may increase transfection efficiency and decrease toxicity.

8.
Zhonghua Fu Chan Ke Za Zhi ; 51(9): 672-677, 2016 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-27671048

RESUMO

Objective: To investigate the value of temporary balloon occlusion of the abdominal aorta in the treatment of complete placenta previa with placenta accreta. Methods: From January 2015 to February 2016, 24 cases of complete placenta previa with placenta accreta were treated with temporary balloon occlusion of the abdominal aorta(the study group)before cesarean, and 24 cases of complete placenta previa with placenta accreta did not receive balloon occlusion(the control group). The operation time, intraoperative blood loss, intraoperative blood transfusion volume, the perioperative hemoglobin level, the hysterectomy rate and the related complications were compared retrospectively.Also, the hospitalization time, the blood coagulation parameters after operation, including activated partial thromboplastin time(APTT), fibrinogen(FIB), D-Dimer and reperfusion injury parameters including creatine phosphokinase(CK), creatine phosphokinase isoenzyme(CK-MB), lactate dehydrogenase(LDH)and serum creatinine were compared between the 2 groups. Results: The blood loss[750 ml(400- 2 000 ml)vs 2 000 ml(1 500- 2 375 ml); Z=-3.214, P=0.001]and blood transfusion volume[200 ml(0-800 ml)vs 800 ml(0-1 200 ml); Z=- 2.173, P=0.030]in the study group were lower than in the control group. The hemoglobin difference between before and after operation in the study group was lower than the control group[(12.8±13.4)g/L vs(22.9±20.1)g/L; t=-2.041, P=0.047]. In the study group, there were still bleeding in 13 cases after releasing the balloon, 5 of them received uterine artery embolization, 5 cases received uterine artery ligation, and 3 cases received uterine packing. One case had venous thrombosis in the right lower limb. Two cases(8%,2/24)in the control group had hysterectomy, while none in the study group, there was no statistical significance(P= 0.489). Conclusions: Temporary balloon occlusion of the abdominal aorta can effectively reduce blood loss and blood transfusion in the treatment of complete placenta previa with placenta accreta, but there is still the risk of continuing bleeding after releasing the balloon. Other methods of hemostasis might be needed.


Assuntos
Aorta Abdominal , Placenta Acreta , Placenta Prévia , Oclusão com Balão , Perda Sanguínea Cirúrgica , Transfusão de Sangue , Cesárea , Feminino , Humanos , Histerectomia , Duração da Cirurgia , Gravidez , Estudos Retrospectivos , Embolização da Artéria Uterina , Útero
9.
J Biol Regul Homeost Agents ; 30(1): 211-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049094

RESUMO

As ultrasound diagnosis is applied more frequently in gynecological acute abdomen, we carried out this study to discuss the diagnosis of endometriosis with ultrasound imaging and analyze the efficacy of microRNA used for diagnosing endometriosis and evaluating prognosis by comparing differentially expressed microRNA in subjects with or without endometriosis. Ultrasound examination results and clinical pathological examination results of 60 cases of gynecological acute abdomen were compared. Blood samples were collected from patients with endometriosis. Of 60 cases, 38 cases recurred in 20 months after surgery and the remaining 22 cases had no recurrence in the 30-month follow-up. Additionally, blood was collected from 40 patients without endometriosis as control. Then total RNA was extracted from these blood samples to determine the difference of expression of microRNA (miR-17-5p, miR-20a, miR-199a and miR-141). Compared to healthy subjects, the endometriosis patients showed significantly increased expression of miR-199a, but the expression of miR-17-5p, miR-20a and miR-141 had an obvious decrease; the differences were statistically significant (p less than 0.01). For recurred cases, miR-199 showed a remarkably high expression and miR-17-5p and miR-20a expressed significantly low.


Assuntos
Abdome Agudo/diagnóstico por imagem , Doenças dos Genitais Femininos/diagnóstico por imagem , Abdome Agudo/complicações , Abdome Agudo/genética , Adulto , Feminino , Regulação da Expressão Gênica , Doenças dos Genitais Femininos/complicações , Doenças dos Genitais Femininos/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Recidiva , Ultrassonografia
10.
Clin Exp Immunol ; 125(2): 283-90, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11529921

RESUMO

We have reported previously that the abnormally down-regulated protein kinase C (PKC) causes cellular dysfunction observed in natural killer (NK) cells, polymorphonuclear leucocytes (PMNs) and fibroblasts from beige mouse, an animal model of Chediak-Higashi syndrome (CHS). Here we show that the abnormal down-regulation of PKC activity also occurs in Epstein-Barr (EB) virus-transformed cell lines from CHS patients. When CHS cell lines were stimulated with concanavalin A (Con A) for 20 min, the membrane-bound PKC activity declined markedly, whereas that in control cell lines increased. We found that E-64-d, which protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and corrected the increased Con A cap formation to almost normal levels in CHS cell lines. We confirmed that the dysregulation of PKC activity also occurred in peripheral blood mononuclear leucocytes (PBMC) from CHS patients and that E-64-d corrected both the declined PKC activity and increased Con A cap formation. E-64-d also corrected the reduced lysosomal elastase and cathepsin G activity in CHS cell lines. In contrast, chelerythrin, a specific inhibitor of PKC, and C2-ceramide, which promotes PKC breakdown induced by calpain, increased Con A cap formation and inhibited both elastase and cathepsin G activity in normal cell lines. Moreover, we found that ceramide production in CHS cell lines increased significantly after Con A stimulation, which coincides with our previous observation in fibroblasts from CHS mice. These results suggest an association between ceramide-induced PKC down-regulation and the cellular dysfunctions in CHS.


Assuntos
Síndrome de Chediak-Higashi/enzimologia , Concanavalina A/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Leucina/farmacologia , Leucócitos Mononucleares/enzimologia , Lisossomos/enzimologia , Proteína Quinase C/metabolismo , Calpaína/antagonistas & inibidores , Catepsina G , Catepsinas/metabolismo , Linhagem Celular Transformada , Ceramidas/biossíntese , Síndrome de Chediak-Higashi/imunologia , Criança , Regulação para Baixo , Antagonismo de Drogas , Feminino , Humanos , Leucina/análogos & derivados , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Elastase Pancreática/metabolismo , Agregação de Receptores/efeitos dos fármacos , Serina Endopeptidases , Esfingomielina Fosfodiesterase/metabolismo
11.
J Leukoc Biol ; 67(5): 749-55, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10811017

RESUMO

We have previously reported that the abnormally rapid down-regulation of protein kinase C (PKC) activity is responsible for the cellular dysfunction in natural killer (NK) cells and polymorphonuclear leukocytes (PMNs) from Chediak-Higashi syndrome (beige) mice. In this report, we examined whether the down-regulation of PKC is associated with giant granule formation in fibroblasts from beige mice. In cultured beige fibroblasts, the membrane-bound PKC activity declined significantly after phorbol ester stimulation. We found that E-64-d, which is a thiol proteinase inhibitor and protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and prevented giant granule formation in beige fibroblasts. Moreover, E-64-d corrected the reduced lysosomal elastase and cathepsin G activity in beige fibroblasts. In contrast, specific PKC inhibitors, chelerythrin and calphostin C, promoted giant granule formation in normal fibroblasts. We also demonstrate that ceramide production is enhanced in beige fibroblasts and is involved in the rapid down-regulation of PKC. These results suggest that the accelerated breakdown of PKC observed in beige fibroblasts is caused by enhanced ceramide production and is also responsible for giant granule formation.


Assuntos
Síndrome de Chediak-Higashi/fisiopatologia , Inibidores de Cisteína Proteinase/farmacologia , Grânulos Citoplasmáticos/ultraestrutura , Fibroblastos/fisiologia , Leucina/análogos & derivados , Proteína Quinase C/metabolismo , Animais , Catepsina G , Catepsinas/metabolismo , Células Cultivadas , Ceramidas/farmacologia , Síndrome de Chediak-Higashi/genética , Grânulos Citoplasmáticos/efeitos dos fármacos , Citosol/enzimologia , Embrião de Mamíferos , Fibroblastos/efeitos dos fármacos , Fibroblastos/ultraestrutura , Leucina/farmacologia , Lisossomos/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Elastase Pancreática/metabolismo , Serina Endopeptidases , Esfingolipídeos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
12.
Biochem Biophys Res Commun ; 242(1): 129-33, 1998 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-9439623

RESUMO

Ceramide has been recognized as an important second messenger in intracellular signaling. We demonstrate here that ceramide promotes the down-regulation of protein kinase C (PKC) activity in phorbol ester-stimulated murine polymorphonuclear leukocytes (PMNs). As reported previously, treatment of PMNs with phorbol ester caused a translocation of PKC from the cytosolic to the membrane fractions. When PMNs were pretreated with cell-permeable ceramide analogue, C2-ceramide, the membrane-associated PKC activity was rapidly down-regulated by phorbol ester stimulation. E64-d, a potent inhibitor of calpain which proteolyzes PKC, eliminated the rapid down-regulation of PKC activity. By hydroxyapatite column chromatography and Western blotting, the predominant PKC isoform was PKC beta with a small amount of PKC alpha in murine PMNs. We found that ceramide strikingly promoted calpain-mediated proteolysis of PKC beta in vitro. Ceramide was also shown to inhibit [3H]phorbol 12,13-dibutyrate(PDBu) binding to PKC beta. Moreover, we show that ceramide stimulates PKC beta autophosphorylation. These results suggest that ceramide directly activates PKC beta and promotes calpain-mediated proteolysis in murine PMNs.


Assuntos
Calpaína/metabolismo , Isoenzimas/metabolismo , Neutrófilos/metabolismo , Proteína Quinase C/metabolismo , Esfingosina/análogos & derivados , Animais , Inibidores de Cisteína Proteinase/farmacologia , Regulação para Baixo , Leucina/análogos & derivados , Leucina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/efeitos dos fármacos , Dibutirato de 12,13-Forbol/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Quinase C beta , Esfingosina/farmacologia
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