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Objective:To analyze the effect of cognitive conflict in teaching practice nurses in emergency department.Methods:102 nursing students who practiced in the emergency department of Huai′an First Hospital Affiliated to Nanjing Medical University were selected as the research objects by quasi-experimental study, 52 students from December 2021 to July 2022 were set as the research group, and 50 students from March 2021 to November 2021 were set as the control group. The control group received on-site first aid sitnation teaching. The research group combined cognitive conflict teaching on the basis of on-site first aid situation teaching, and compared the emergency nursing skills, theoretical knowledge, critical thinking, clinical strain ability and teaching satisfaction of the two groups of interns.Results:After practice, the scores of emergency nursing skills, theoretical knowledge, critical thinking ability, clinical adaptability and satisfaction with the teaching mode (theoretical memory, interest in learning, practical ability) in the research group were (87.25 ± 2.66), (90.01 ± 2.74), (298.10 ± 8.27), (84.37 ± 3.45), (90.13 ± 3.26), (89.03 ± 3.37) and (91.34 ± 3.16), which were significant higher than the (83.76 ± 2.87), (85.16 ± 3.11), (290.47 ± 8.55), (80.05 ± 3.68), (85.46 ± 3.53), (86.28 ± 3.61) and (88.47 ± 3.38), the difference were significant ( t values were 3.98-8.37, all P<0.05). Conclusions:Cognitive conflict teaching can significantly improve the professional level, critical thinking and clinical adaptability of nursing interns and their satisfaction with teaching.
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OBJECTIVE@#To evaluate the safety and efficacy of reverse partial lung resection for treatment of pediatric pulmonary cysts combined with lung abscesses or thoracic abscess.@*METHODS@#We retrospectively analyzed the clinical data of children undergoing reverse partial lung resection for complex pulmonary cysts in our hospital between June, 2020 and June, 2021.During the surgery, the patients lay in a lateral position, and a 3-5 cm intercostal incision was made at the center of the lesion, through which the pleura was incised and the fluid or necrotic tissues were removed.The anesthesiologist was instructed to aspirate the sputum in the trachea to prevent entry of the necrotic tissues in the trachea.The cystic lung tissue was separated till reaching normal lung tissue on the hilar side.The proximal end of the striated tissue in the lesion was first double ligated with No.4 silk thread, the distal end was disconnected, and the proximal end was reinforced with continuous sutures with 4-0 Prolene thread.The compromised lung tissues were separated, and the thoracic cavity was thoroughly flushed followed by pulmonary inflation, air leakage management and incision suture.@*RESULTS@#Sixteen children aged from 3 day to 2 years underwent the surgery, including 3 with simple pulmonary cysts, 11 with pulmonary cysts combined with pulmonary or thoracic abscess, 1 with pulmonary cysts combined with tension pneumothorax and left upper lung bronchial defect, and 1 with pulmonary herpes combined with brain tissue heterotaxy.All the operations were completed smoothly, with a mean operation time of 129 min, an mean hospital stay of 11 days, and a mean drainage removal time of 7 days.All the children recovered well after the operation, and 11 of them had mild air leakage.None of the children had serious complications or residual lesions or experienced recurrence of infection after the operation.@*CONCLUSION@#Reverse partial lung resection is safe and less invasive for treatment of complex pediatric pulmonary cysts complicated by infections.
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Humanos , Niño , Absceso , Estudios Retrospectivos , Pulmón/cirugía , Quistes/cirugía , BronquiosRESUMEN
Objective:To identify the risk factors for early neurological complications after revascularization in adult patients with moyamoya disease.Methods:The medical records of patients of both sexes with moyamoya disease, aged 18-65 yr, of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, who underwent revascularization in our hospital from January 2017 to June 2019, were retrospectively collected.According to the occurrence of early postoperative neurological complications, patients were divided into early postoperative neurological complication group and non-early postoperative neurological complication group.The factors such as patient′s age, gender, preoperative clinical symptoms, previous history of hypertension, history of diabetes, history of coronary heart disease, American Society of Anesthesiologists physical status, methods of anesthesia, type of operation, anesthesia time, time for start of operation, operation time, intraoperative urine volume, times of intraoperative vasoactive drugs used, and time of the post-anaesthesia observation room (PACU) stay were collected.Logistic regression analysis was used to identify the risk factors for postoperative early neurological complications.Results:A total of 510 adult patients with moyamoya disease underwent revascularization were enrolled in this study, and the incidence of early postoperative neurological complications was 9.0%.The results of logistic regression analysis showed that preoperative ischemia, intraoperative use of vasoactive drugs more than 3 times and PACU stay time>90 min were risk factors for postoperative neurological complications ( P<0.05). Conclusion:Preoperative ischemia, intraoperative use of vasoactive drugs >3 times and PACU stay time>90 min are risk factors for early neurological complications after revascularization in the patients with moyamoya disease.
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Background and Objectives@#Mesenchymal stromal cells (MSCs)-based treatment for degeneration of intervertebral disc (IVD) has been proposed recently. We here addressed whether MSC secreted factors can rejuvenate nucleus pulposus- derived stem/progenitor cells from degenerated disc (D-NPSCs) in vitro. @*Methods@#and Results: We analyzed the expression of MSCs and NP cell specific surface markers, pluripotency related genes, multilineage potential and cell proliferative capacity of D-NPSCs upon incubation with the conditioned medium which was collected from the umbilical cord derived MSCs (UCMSCs). Our results indicated that the conditioned medium restore the stemness of D-NPSCs by up-regulating the expression level of CD29 and CD105, pluripotency related genes OCT4 and Nanog, and NP progenitor marker Tie2. The increased stemness was accompanied by promoted cell proliferative capacity and improved osteogenic and chondrogenic differentiation potential. @*Conclusions@#Our findings suggested that the UCMSCs derived conditioned medium might be used to rejuvenate the degenerated NP stem/progenitor cells.
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AIM:To explore a novel method to isolate human nucleus pulposus mesenchymal stem cells (hNP-MSCs) in vitro and to identify their biological characteristics.METHODS:The explant culture method was employed to isolate hNP-MSCs from nucleus pulposus tissue obtained by percutaneous endoscopic lumbar discectomy (PELD).The isolated cells were passaged for purification and cultured in vitro followed by morphological observation.The cell proliferation ability was detected by CCK-8 assay.Growth curves of the cells were drawn and surface antigens were detected by flow cytometry.The cells at the 3rd~6th passages were induced for adipogenic, osteogenic and chondrogenic differentiation, and examined by oil red O staining, alizarin red staining and Alcian blue staining.RESULTS:The cells with self-renewal were obtained from nucleus pulposus tissue obtained by PELD.The results of flow cytometry analysis revealed that the cells were positive for CD29, CD44, CD90, CD73 and CD105, but negative for CD34 and CD45.The proliferative capacity was consistent with the growth characteristics of MSCs and multilineage differentiation potential was identified.CONCLUSION:A novel method to efficiently isolate and culture hNP-MSCs,PELD combined with explant culture method,was established, which would promote the study of regenerative medicine based on hNP-MSCs.
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BACKGROUND: Increasing evidences support that the physical properties, especially stiffness, can regulate the directional differentiation of stem cells.OBJECTIVE: To review the effects of extracellular matrix on stem cell behaviors, and the research progress concerning the influence of physical properties of biomaterials on stem cell differentiation.METHODS: The first author retrieved CNKI and Web of Science databases using the keywords of extracellular matrix, bioscaffolds materials, chemical property, physical property, substrate rigidity, stem cell differentiation in Chinese and English, respectively. Finally, a total of 31 literatures were included for analysis.RESULTS AND CONCLUSION: The physicochemical properties expose effects on the cell proliferation, migration and differentiation, and especially the regulatory effect of stiffness on the cell differentiation has a revelation for tissue engineering and regenerative medicine. Searching for more biochemical and physical factors interacting with the stiffness of extracellular matrix will enable us to control cell behaviors accurately and to prepare an ideal scaffold closely similar to in vivo environment.
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Aims To study the effects of diterpenoid pekinenal of Euphorbia pekinensis Rupr. on cell prolif-eration, cell cycle phase and apoptosis of hepatoma SMMC-7721 cells and to probe into its anti-cancer mechanisms. Methods MTT assay was used to inves-tigate the effect of pekinenal on proliferation of SMMC-7721 cells; TUNEL method, Annexin V/PI staining and electron microscopy were employed to observe the cell apoptosis; Flow cytometry was applied to analyze the distribution of cell cycle. Results Proliferation of SMMC-7721 cells was markedly inhibited by pekinenal in a dose-dependent manner; Annexin V/PI staining showed that with the increase of pekinenal concentra-tion, apoptotic rate of SMMC-7721 cells increased sig-nificantly, compared with control group, the difference has significant statistical significance ( P < 0. 01 ) . TUNEL method test results showed that different con-centrations of pekinenal in SMMC-7721 cells could in-duce liver cancer cell apoptotic and apoptotic index ( AI) increased significantly ( P <0. 01 ) with the in-crease of drug concentration. Compared with control group, electron microscope found that after the treat-ment, hepatocyte mitochondrial swelling, endoplasmic reticulum expansion, cytoplasm inclusion body forma-tion, part of the nucleus apoptosis, and the more obvi-ous apoptosis appeared with the increase of drug con-centration. Flow cytometry analysis showed that differ-ent concentrations of pekinenal could all make the cell block in S phase. Conclusion Pekinenal has an obvi-ously inhibitory effect on the human liver cancer cells, and there is significant concentration dependence; Pe-kinenal probably inhibits cancer cell DNA synthesis for the human liver cell cycle arrest in S phase and inhibits the proliferation . It plays a role in liver cancer inhibi-tion by inducing liver cancer cells apoptosis, etc.
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Background and purpose:The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial has been described as practice-changing of sentinel lymph node (SLN) positive breast cancers. The goal of this study was to determine the exportability of the criteria deifned by Z0011 trial for selecting patients who are eligible for avoiding axillary lymph node dissection (ALND) after a positive sentinel lymph node biopsy (SLNB) result in China.Methods:We collected 194 breast cancer patients with positive SLNs and classiifed them into two groups according to Z0011 criteria. One group was consisted of patients who were eligible for omitting ALND and with SLNB only. The other one was ALND group. Then the patients of SLNB group were compared with cohort included in the Z0011 trial and the ALND group of this study separately.Results:Seventy-seven patients were potentially eligible for omitting ALND and 117 patients were still needed to have ALND. Compared with Z0011 cohort, the SLNB group in this research had signiifcantly more T1 stage and ER positive tumors (P<0.05). More patients in SLNB group had positive LNs with the number less than 3 and negative NSLNs (P<0.05). The ALND group had more T2 and T3 stage tumors than the SLNB group but the difference was not signiifcantly. The number of positive LNs in ALND group was higher than the SLNB group signiifcantly (P<0.05). More patients in the ALND group had positive non-sentinel lymph node (NSLN) than the SLNB group and the difference was also signiifcantly (P<0.05).Conclusion:Applied to the SLN positive patients in this study, Z0011 criteria could make patients with better prognosis and lower risk than Z0011 cohort be selected and let these patients avoiding ALND more safely.
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[ ABSTRACT] AIM:To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs).METHODS: Using the method of solvent e-vaporation induced phase separation, the cell model of polymer/liquid crystal was constructed.The surface morphology and phase separation structure were determined by polarized optical microscopy ( POM) , scanning electron microscopy ( SEM) and small angle X-ray scattering ( SAXS ) .rBM-MSCs were separated and expanded by adherent culture.The surface markers of rBM-MSCs were detected by flow cytometry.The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks.After 3 passages, the cells were divided into 4 groups, including total PU control group, 10%membrane group, 30%membrane group and 50%membrane group.The cells were then incubated with rhodamine phalloi-din for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h.RE-SULTS:The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation in-duced phase separation.Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45.After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously.The cytoskeleton staining result indicated that the area in total PU control group, 10%membrane group and 30%membrane group were greater, and the actin microfilaments were also clearer than that in 50%membrane group.CONCLUSION:The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs’ adhesion, but too much liquid crystal inhibits cell adhesion.
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[ABSTRACT]AIM:Toexploretheeffectoftheelasticmodulusandsizesofliquidcrystal(LC)phasesonosteo-genic differentiation based on OPC/PU composite substrate by mimicking the microenvironment in rat bone mesenchymal stem cells (rBMSCs).METHODS: A series of composite substrates with different elastic modulus were constructed via modulation of LC content in the composites .The surface phase structure was observed by polarized microscopy , and the mechanical property was measured by a universal material testing machine .Furthermore, the laser confocal microscope was employed to observe the spreading , polarization and the cytoskeleton arrangement of the rBMSCs .The proliferation of rBM-SCs was evaluated by CCK-8 assay.The specific mRNA expression of osteogenic differentiation such as collagen Ⅰ, and osteopontin on the composite membranes was detected by real-time PCR.RESULTS:The size and number of LC phase in-creased and the elastic modulus of the composite substrates decreased with the increase of the LC content .The rBMSCs ex-hibited better characteristics of initial adhesion , spreading and proliferation on the OPC 10-PU and OPC30-PU in the early and medium culturing .The rBMSCs displayed higher expression of collagen Ⅰ and osteopontin on the OPC10-PU in the early and medium osteogenic induction , while the high expression of these osteogenic genes occured on the OPC 30-PU and OPC50-PU in later osteogenic induction .The emphasis of genetic expression was switched from collagen Ⅰin the early and medium osteogenic induction to osteopontin in the later stage .CONCLUSION:When the content of LC remained low in the composite substrates , rBMSCs mainly responded to the mechanical stimuli induced by substrate stiffness and exhibited distinguished cellular behaviors;with the increase in the LC content , rBMSCs had strong interactions with LC by sensing the viscoelasticity of LC , probably resulted from the contribution of both substrate stiffness and the viscoelasticity of LC phase .
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[Summary] The population of the world is aging. This makes the endocrinologists recognize many aspects of hormones and diseases that are associated with the aging process, and developed a new endocrinology of aging. This has led to increasing attempts to explore the use of hormonal replacement as a modality to retard the aging process. Although at present, many are unsuccessful, especially in long term outcomes. Many questions are to be resolved in our country, as we are one of the largest countries in the world with high percentage of older population.
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BACKGROUND: Though there were many experiments addressing repairing osteochondral defects before, faulty restoration occurred at coupling interfaces. OBJECTIVE: To investigate the feasibility of repairing of osteochondral composite defects in rabbit knees with animal-origin osteochondral scaffold combined with bone marrow mesenchymal stem cells (BMSCs)/chondrocytes.METHODS: New Zealand white rabbits were randomly divided into the experimental, control and blank groups and prepared for unilateral knee joint osteochondral defects. Animal-origin osteochondral scaffold combined with BMSCs/chondrocytes, animal-origin osteochondral scaffold and no material was implanted to repair the defects in the experimental, control and blank groups, respectively. Healing condition was evaluated by gross observation, hematoxylin-eosin staining, and toluidine blue staining at 4, 8, and 12 weeks after operation. RESULTS AND CONCLUSION: At 12 weeks after operation, gross observation showed the defects were repaired completely without local depression and the regenerated tissues were fused with surrounding tissues in the experimental group. Hematoxylin-eosin staining and toluidine blue staining revealed that there were many new hyaline cartilages in the cartilage defects in which columnar cells were lined well and cartilage lacuna was obviously, also, there were many bony tissues in the bone defects. The regeneration cartilage, the underlying subchondral bone and host bone were coupled completely. The toluidine blue positive rate and histologic scores of the experimental group were superior to those of the control and blank groups (P < 0.05). It is demonstrated that animal-origin osteochondral scaffold combined with BMSCs/chondrocytes is an ideal method to repair defects between cartilage and the underlying subchondral bone.
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BACKGROUND: The development of cartilage tissue engineering provides novel ideas for treatment of articular cartilage defects and implements construction of tissue-engineered cartilage in vivo.OBJECTIVE: To investigate the feasibility of constructing tissue-engineered osteochondral composite through bone marrow stem cells(BMSCs) cultured on the poly(lactide-co-glycolic acid) (PLGA), which was modified with collagen and cellular growth factors.METHODS: PLGA was made by phase separation technique, composited with collagen Ⅱ, basic fibroblast growth factor, and transforming growth factor-β1. The BMSCs of passage 3 were cultured on the above scaffolds. Thirty-six SD rats were randomly divided into experimental, control, and blank groups. These three groups received implantation of BMSCs composited with growth factors and collagen-PLGA, implantation of BMSCs composited with collagen-PLGA, and implantation of collagen-PLGA into the muscle, respectively. At 4, 8, and 12 weeks after surgery, cell directional differentiation and growth were examined by gross observation, hematoxylin-eosin staining, toluidine blue staining, collagen Ⅱ staining, and scanning electron microscope.RESULTS AND CONCLUSION: Gross observation showed that there were many chondroid tissues in the experimental group and fibrous tissues in the control and black groups. Stainings and electron microscope revealed that many chondroblasts and a few osteoclasts appeared in the composite of the experimental group. Toluidine blue and collagen Ⅱ stainings were positive in the experimental group and negative in the control and blank groups. These findings demonstrate that PLGA modified with collagen had a good cellular compatibility. BMSCs cultured on PLGA, which was modified with collagen and cellular growth factors, can construct the tissue-angineered osteochondral composite in rats.
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Diabetic patients are at increased risk of some cancers,mainly pancreatic cancer,liver cancer,colorectal cancer,breast cancer,endometrial cancer,etc.,and these cancers often result in higher mortalities than that in nondiabetics.The exact mechanism of this relationship is still unclear.The most suggested factor are hyperinsulinemia and insulin-like growth factors with their growth promoting and mitogenic effects.Recently,some insulin analogues are suspected to have these carcinogenic effects,but no firmly proven data are available yet.Metformin may have a protective effect in this regard.
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Some issues in the evaluation of insulin resistance in experimental research were discussed.Except glucose clamp test, other methods used in animal experiments are not appropriate now.
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Progress of diabetes researches in traditional Chinese medicine (TCM), mainly the work on herb extracts or ingredients at cellular or molecular levels in recent years, was reviewed. The Chinese herbs investigated mostly are qi-invigorating drugs and heat-clearing and detoxifying drugs. It shows that TCM therapy bears positive effect on diabetes mellitus.
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AIM: To establish hybrid mouse embryonic stem (ES) cell line from blastocysts of the (C57BL/6J × 129/J) F1 mouse. METHODS: 3.5 days post- coitus (d.p.c.) blastocysts were cultured on mouse embryonic fibroblasts (MEFs) in the medium, after 3 - 4 days, Inner cell mass were picked up and disaggregated, then reseeded. After the ES - like colonies appeared, passaged them to give permanent ES cell lines. The pluripotent propertes of ES cells obtained were analyzed by alkaline phosphatase (AKP) activity, expression of SSEA- 1 and Oct-4, and their capacity to form teratoma. RESULTS: Two hybrid ES cell lines, SC1001, SC1002 were obtained from blastocysts of the (C57BL/6J × 129/J) F1 genotype. Most of these ES cells had a normal karyotype and an XY sex chromosome composition. The pluripotent properties of the cell lines were analyzed on the basis of their alkaline phosphatase activity, expression of SSEA - 1 and Oct - 4, and their capacity to form teratoma in severe combined immunodeficiency (SCID) mice. CONCLUSION: Two hybrid mouse ES cell lines having pluripotent properties and capacity for long - term self renewal were generated from blastocysts of the ( C57BL/6J × 129/J) F1 genotype.
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Scientificity was emphasized in researches on diabetes mellitus in integrated traditional Chinese and western medicine abroad. In clinical researches, random and double-blind method, placebo control and auto-cross-over experiment were employed, and the diet, activity, drug dosage and body weight were under strict control, although such kind of researches was rare. During the past few decades, there were also some good achievements in the researches on diabetes mellitus in integrated traditional Chinese and western medicine in China, but most of the researches were duplicated work at low level. There existed some problems, such as the selection of investigated objects, control of the facts besides of the drugs, randomized grouping, blind method, auto-cross-over control, integrated research of multi-center, selection of indexes, methods of index detection, selection of complex prescription, single drug or monome, animal model, etc. The scientificity of the researches in China should be further improved.
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<p><b>OBJECTIVE</b>To compare the efficacy and toxicity of two different regimens as neoadjuvant chemotherapy for breast cancer.</p><p><b>METHODS</b>Forty-eight patients with stage II, III breast cancer as proved by cytology biopsy, were treated with either 5-Fu, epirubicin, cyclophosphamide (FEC) or epirubicin, paclitaxel (ET) regimens for 2 cycles every 3 - 4 weeks. Clinical responses in the breast and lymph nodes were assessed after 2 cycles of neoadjuvant chemotherapy. Patients in FEC arm received combination of 5-fluorouracil (5-Fu) 500 mg/m(2) by 4-hour continuous infusion on D1 and D8, epirubicin (EPI) 50 mg/m(2) by intravenous injection on D1, and cyclophosphamide (CTX) 500 mg/m(2) by intravenous injection on D1 and D8. Patients assigned to the ET arm received EPI 60 mg/m(2) by intravenous injection on D1, paclitaxel (TAX) 150 mg/m(2) by 3-hour continuous infusion on D2. All patients were treated by operation 2 weeks later and radiotherapy was added to some.</p><p><b>RESULTS</b>For primary tumor in the breast, the overall response rate (RR) was 50.0% (12/24) in FEC arm and 79.2% (19/24) in ET arm. One patient showed clinical complete response (cCR), 11 partial response (PR), 12 no change (NC) after the FEC therapy, while 1 patient showed CR, 18 PR, 5 NC after ET therapy. There was no pathologic complete response or progressive disease, though a higher proportion of RR was observed in stage II than stage III patients in these two groups. Clinically palpable axillary lymph nodes which had been found in all 48 patients before 2 cycles of treatment, 50.0% (12/24) in the FEC patients and 66.7% (16/24) in the ET patients became in-palpable. The major toxicity, including leukopenia, gastroenteric reactions, were similar in both groups, but alopecia was more severe and arthralgia, myalgia, neurotoxicity and flushing of face were the unique features of the ET regimen.</p><p><b>CONCLUSION</b>Neoadjuvant chemotherapy with two different regimens were effective to the primary tumor and axillary metastatic lymph nodes of breast cancer, and the side effects were tolerable. Higher efficacy and more side effects are observed in ET than in FEC regimen.</p>
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Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica , Usos Terapéuticos , Neoplasias de la Mama , Quimioterapia , Ciclofosfamida , Usos Terapéuticos , Epirrubicina , Usos Terapéuticos , Fluorouracilo , Usos Terapéuticos , Terapia Neoadyuvante , Estadificación de Neoplasias , Paclitaxel , Usos Terapéuticos , Taxoides , Resultado del TratamientoRESUMEN
<p><b>OBJECTIVE</b>To investigate the MEK and ERK expression and their relationship with clinicopathological parameters in human breast carcinoma, and the effect of preoperative chemotherapy on MEK and ERK protein expression.</p><p><b>METHODS</b>Samples were obtained from 56 patients with breast carcinoma and 8 patients with benign tumors. Sixteen of the 56 patients received preoperative chemotherapy. Western blot and immunohistochemistry were used to measure the expression of MEK1, MEK2 and ERK1, ERK2 protein.</p><p><b>RESULTS</b>MEK2 and ERK1, ERK2 protein levels were increased in breast carcinoma tissue compared with those in adjacent normal tissues (t = 7.244, 5.959, 3.735, P < 0.01) and benign tumors (t = 2.206, P < 0.05). The levels of MEK1 were decreased. The expression of MEK2 protein in ER negative patients was higher than that in ER positive ones. MEK2 protein levels were lower in patients who received preoperative chemotherapy than in those who did not.</p><p><b>CONCLUSION</b>Overexpression of MEK-ERK may play an important role in the development of human breast carcinoma. MEK and ERK protein expressions are inhibited by preoperative chemotherapy.</p>