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1.
BMC Cardiovasc Disord ; 23(1): 624, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129785

RESUMO

BACKGROUND: Richter's syndrome (RS) defines the transformation of chronic lymphocytic leukemia into high-grade lymphoma, which usually involves lymph nodes and bone marrow. Extranodal involvement of the heart is an extremely rare condition. Patients with heart involvement tended to have a low response to chemotherapy and relative poor prognosis. The transformation process of RS is often insidious and nonspecific making it challenging to diagnose. CASE PRESENTATION: A 64-year-old woman wih a history of chronic lymphocytic leukemia (CLL) presented with intermittent chest pain and was diagnosed with non-ST-elevation myocardial infarction (NSTEMI). However, the contrast enhanced echocardiography revealed a large irregular mass, measuring about 75.4 mm × 37.5 mm, located on the lateral and posterior wall of the right ventricle. Biopsy of the cardiac mass and the results revealed diffuse large B-cell lymphoma. CONCLUSIONS: We present a case of a 64-year-old woman with aggressive diffuse large B-cell lymphoma involving the heart. This case could provide some insights in the diagnosis of cardiac lymphoma.


Assuntos
Neoplasias Cardíacas , Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Feminino , Humanos , Pessoa de Meia-Idade , Biópsia , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/patologia
3.
Org Biomol Chem ; 21(21): 4388-4392, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37161754

RESUMO

The regioselective [3 + 2] cycloaddition reaction of 2-benzylidene-1-indenones with functional olefins was established with DABCO as a base under mild conditions. Using this approach, a series of diversely substituted indanone-fused cyclopentane polycycles with highly crowded multiple substituents were synthesized in high yields.

4.
World J Clin Cases ; 10(19): 6609-6616, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35979281

RESUMO

BACKGROUND: Metastasis to the penis is an unusual event, and penile metastasis from rectal carcinoma (PMRC) is extremely rare and associated with a dismal prognosis. Thus far, approximately 80 cases have been reported. CASE SUMMARY: Herein, we report the case of a 49-year-old man with PMRC. The patient presented to the urology clinic with a complaint of penile pain during urination. The patient underwent the Dixon operation for rectal carcinoma 2 mo before the presentation. During hospitalisation, abdominal computed tomography revealed a nodular lesion on the left penis. The postoperative pathological examination revealed a typical intestinal-type adenocarcinoma. Previous cases of PMRC were retrieved from PubMed to characterise the clinicopathological features and identify the prognostic factors of PMRC. CONCLUSION: The analysis suggested that approximately 24 mo is the median time to metastasis occurrence and 150 d is the survival time after diagnosis. Furthermore, poor pathological differentiation, lymph node involvement of the primary RC, metastasis time < 6 mo, penile metastatic nodule diameter > 1 cm, and treatment abandonment are negative predictors of survival outcomes. Close follow-up, surgical resection, chemotherapy, and radiotherapy may potentially improve the prognosis of patients.

5.
Neural Regen Res ; 17(11): 2530-2536, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35535907

RESUMO

Spinal muscular atrophy (SMA) is a rare hereditary neuromuscular disease with a high lethality rate in infants. Variants in the homologous genes survival of motor neuron (SMN)1 and SMN2 have been reported to be SMA pathogenic factors. Previous studies showed that a high inclusion rate of SMN2 exon 7 increased SMN expression, which in turn reduced the severity of SMA. The inclusion rate of SMN2 exon 7 was higher in neural tissues than in non-neural tissues. Neuro-oncological ventral antigen (NOVA) is a splicing factor that is specifically and highly expressed in neurons. It plays a key role in nervous system development and in the induction of nervous system diseases. However, it remains unclear whether this splicing factor affects SMA. In this study, we analyzed the inclusion of SMN2 exon 7 in different tissues in a mouse model of SMA (genotype smn-/-SMN22tg/0) and littermate controls (genotype smn+/-SMN22tg/0). We found that inclusion level of SMN2 exon 7 was high in the brain and spinal cord tissue, and that NOVA1 was also highly expressed in nervous system tissues. In addition, SMN2 exon 7 and NOVA1 were expressed synchronously in the central nervous system. We further investigated the effects of NOVA1 on disease and found that the number of neurons in the anterior horn of spinal cord decreased in the mouse model of SMA during postnatal days 1-7, and that NOVA1 expression levels in motor neurons decreased simultaneously as spinal muscular atrophy developed. We also found that in vitro expression of NOVA1 increased the inclusion of SMN2 exon 7 and expression of the SMN2 protein in the U87MG cell line, whereas the opposite was observed when NOVA1 was knocked down. Finally, point mutation and RNA pull-down showed that the UCAC motif in SMN2 exon 7 plays a critical role in NOVA1 binding and promoting the inclusion of exon 7. Moreover, CA was more essential for the inclusion of exon 7 than the order of Y residues in the motif. Collectively, these findings indicate that NOVA1 interacts with the UCAC motif in exon 7 of SMN2, thereby enhancing inclusion of exon 7 in SMN2, which in turn increases expression of the SMN protein.

7.
Neural Regen Res ; 16(3): 531-536, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32985483

RESUMO

Perceiving pitch is a central function of the human auditory system; congenital amusia is a disorder of pitch perception. The underlying neural mechanisms of congenital amusia have been actively discussed. However, little attention has been paid to the changes in the motor rain within congenital amusia. In this case-control study, 17 participants with congenital amusia and 14 healthy controls underwent functional magnetic resonance imaging while resting with their eyes closed. A voxel-based degree centrality method was used to identify abnormal functional network centrality by comparing degree centrality values between the congenital amusia group and the healthy control group. We found decreased degree centrality values in the right primary sensorimotor areas in participants with congenital amusia relative to controls, indicating potentially decreased centrality of the corresponding brain regions in the auditory-sensory motor feedback network. We found a significant positive correlation between the degree centrality values and the Montreal Battery of Evaluation of Amusia scores. In conclusion, our study identified novel, hitherto undiscussed candidate brain regions that may partly contribute to or be modulated by congenital amusia. Our evidence supports the view that sensorimotor coupling plays an important role in memory and musical discrimination. The study was approved by the Ethics Committee of the Second Xiangya Hospital, Central South University, China (No. WDX20180101GZ01) on February 9, 2019.

8.
Medicine (Baltimore) ; 99(51): e23793, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33371150

RESUMO

ABSTRACT: To compare pregnancy outcomes between patients with gestational diabetes mellitus (GDM) with and without their own blood glucose meter.We conducted a retrospective-cohort study of 835 women with GDM at the Second Hospital of Tianjin Medical University, Tianjin, China from 1 January 2016 to 31 December 2018. Perinatal outcomes of these patients were monitored and collected in the Tianjin Maternal and Child Health System. Each patient was advised by a certified clinical nutritionist regarding dietary analysis and lifestyle recommendations. All pregnant women with GDM were divided into the following 2 groups according to whether they had their own blood glucose meter: women with self-measured blood glucose levels with a routine obstetric examination in the study group (n = 424); and those with non-self-measured blood glucose levels with a double obstetric examination in the control group (n = 411). Maternal and fetal pregnancy outcomes were compared between these 2 groups. According to different self-management modes, the women were also divided into eight subgroups to compare blood sugar control and compliance with recommended insulin therapy.The cesarean section rate was significantly lower in the study group than in the control group (P < .05). The prevalence of large-for-gestational age (P < .05) and macrosomia was significantly lower in the study group than in the control group (both P < .05). The prevalence of appropriate-for-gestational age was significantly higher in the study group than in the control group (P < .05). Birth weight was significantly lower in the study group than in the control group (P < .05). The mean times for blood sugar control and from the doctor recommendation for insulin treatment to the patient compliance in the study group were significantly shorter than those in the control group (both P < .05). The proportion of insulin required in the study group was significantly lower than that in the control group (P < .05). There were no significant differences in the time of controlling blood sugar and compliance among the 4 subgroups of the study group. However, subgroups with a dietary diary in the control group were better.Self-monitoring blood sugar plus a routine obstetric examination can help patients with GDM control blood sugar, even without dietary diaries and treadmills. In addition to increasing the number of obstetric examinations, recording dietary diaries is helpful for controlling blood sugar in patients with GDM who are unwilling to measure blood sugar by themselves.


Assuntos
Automonitorização da Glicemia/instrumentação , Diabetes Gestacional/terapia , Resultado da Gravidez/psicologia , Adulto , Glicemia/análise , Automonitorização da Glicemia/psicologia , Automonitorização da Glicemia/normas , China , Estudos de Coortes , Diabetes Gestacional/sangue , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/prevenção & controle , Estudos Retrospectivos
9.
Curr Med Sci ; 40(4): 642-645, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32767262

RESUMO

The SARS-CoV-2 infection status of hospitalized children was surveyed in the department of pediatric hematology and oncology in three different hospitals of epidemic areas in Hubei, China. A cross-sectional study was performed to investigate the clinical characteristics, lung CT scan, SARS-CoV-2 nucleic acid test and serum antibodies of hospitalized children with hemato-oncological diseases from January 23 to April 24, 2020. 299 children were enrolled in this study, including 176 males (58.9%) and 123 females (41.1%), aged from 2 months to 16 years. 255 cases (85.3%) received chemotherapy or other immunosuppressive therapies, and there were 44 cases (14.7%) of other benign diseases. Nucleic acid test was performed on 258 children (86.3%) and one case was positive. 163 cases (54.5%) were tested for serum antibodies, and all of them were negative. Lung CT scan was performed on 247 children (82.6%), and 107 of them showed infectious changes. Only one case (0.33%) of COVID-19 was diagnosed in the group. The prevalence rate of COVID-19 in enrolled children with hemato-oncological diseases in Hubei was 0.33%. Immunosuppressed patients are not prone to produce related antibodies. Comprehensive protective measures and ward management can reduce the risk of SARS-CoV-2 infection in the group patients.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Doenças Hematológicas/epidemiologia , Neoplasias/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Adolescente , COVID-19 , Teste para COVID-19 , Criança , Criança Hospitalizada , Pré-Escolar , China/epidemiologia , Técnicas de Laboratório Clínico/métodos , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/prevenção & controle , Estudos Transversais , Feminino , Humanos , Lactente , Controle de Infecções , Masculino , Programas de Rastreamento , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/prevenção & controle , Prevalência , Fatores de Risco , SARS-CoV-2 , Inquéritos e Questionários
10.
Free Radic Biol Med ; 155: 69-80, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32445866

RESUMO

PURPOSE: Myocardial ischemia/reperfusion injury (IRI) induces cardiomyocytes death and leads to loss of cardiac function. Circular RNAs (circRNA) have gain increasing interests in modulating myocardial IRI. In this study, we aim to investigate the role and exact mechanism of circTLK1 in the pathogenesis of myocardial IRI. METHODS: Myocardial IRI was developed in mice with measuring hemodynamic parameters and the activity of serum myocardial enzymes to evaluate cardiac function. HE and TTC staining were performed to assess infarct area. Expression patterns of circTLK1 and miR-214 were investigated using qRT-PCR assay. Gene expression of circTLK1, miR-214 or RIPK was altered by transfecting with their overexpression or knockdown vectors. The apoptosis of cardimyocytes was assessed by TUNEL staining and Caspase-3 activity analysis. Apoptosis-related markers Bcl-2, Bax, and caspase3, as well as TNF-α signals were determined by western blotting. The interactions of circTLK1/miR-214 and miR-214/RIPK1 were verified using luciferase reporter assay. RNA immunoprecipitation (RIP) was subjected to further definite the direct binding of circTLK1/miR-214. The regulatory network of circTLK1/miR-214/RIPK1 was further validated in vivo. RESULTS: circTLK1 was an up-regulated circRNA found in a myocardial IRI mouse model. Mice with silencing circTLK1 significantly alleviated the impaired cardiac function indexes and decreased infarct area, thus attenuating the pathogenesis of myocardial IRI. Knockdown of circTLK1 dramatically decreased cardiomyocytes apoptosis, which was determined by apoptosis-related proteins. miR-214 was identified as a downstream effector to reverse circTLK1-mediated damage effects in myocardial IRI. miR-214 could directly target RIPK1 via binding to its' 3'-UTR. Overexpression of RIPK1 led to impaired cardiac function indexes, increased infarct area, and cell apoptosis, which abolished the protective effects of miR-214. The TNF signaling pathway was demonstrated to be involved in the circTLK1/miR-214/RIPK1 regulatory network in myocardial IRI. CONCLUSION: Taken together, our study revealed an up-regulated circRNA, circTLK1, could exacerbate myocardial IRI via targeting miR-214/RIPK1-mediated TNF signaling pathway, which may provide therapeutic targets for treatment.


Assuntos
MicroRNAs , Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Animais , Apoptose , Modelos Animais de Doenças , Camundongos , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/genética , Miócitos Cardíacos , RNA Circular , Proteína Serina-Treonina Quinases de Interação com Receptores , Traumatismo por Reperfusão/genética , Transdução de Sinais
11.
Oncol Lett ; 18(4): 3792-3802, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31579409

RESUMO

The present study focused on exploring the inhibitory mechanism of microRNA (miR)-23a in endometrial cancer. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to investigate miR-23a expression in endometrial tissues and endometrial cancer cells. A colony formation assay using crystal violet staining was performed to compare cell proliferation, while wound-healing and Transwell assays were performed to compare cell migration and invasion. Subsequently, bioinformatics and a luciferase reporter gene assay were used to investigate the effect of miR-23a on sine oculis homeobox homolog 1 (SIX1) expression, and the biological function of SIX1 was analyzed. Additionally, a nude mouse tumorigenicity assay was performed to test the inhibitory effect of miR-23a and Taxol® therapy in endometrial cancer. Finally, immunohistochemistry and RT-qPCR were used to explore the association between miR-23a and SIX1 expression in endometrial cancer tissues. miR-23a was underexpressed in endometrial cancer tissues compared with in para-carcinoma tissues, and the overexpression of miR-23a inhibited proliferation and invasion of endometrial cancer cells. Furthermore, SIX1 was demonstrated to be a downstream target of miR-23a, and miR-23a reduced SIX1 expression. Additionally, SIX1 inversely promoted cell proliferation, migration and invasion. In addition, the effects of reduced cell proliferation and increased cell invasion following miR-23a overexpression could be reversed by adding SIX1 to in vitro culture. Furthermore, the inhibitory effect of miR-23a and Taxol therapy, which reduced SIX1 expression in endometrial cancer, was demonstrated in vivo. Finally, a negative association between miR-23a and SIX1 expression was demonstrated in endometrial cancer tissues. The results of the present study revealed that miR-23a may inhibit endometrial cancer development by targeting SIX1.

12.
Cell Biosci ; 9: 75, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31548876

RESUMO

BACKGROUND: Cervical cancer is the most common gynecological malignancy with low terminal cure rate, and therefore new therapeutic targets are urgently needed to combat this disease. SMYD2, as an oncogene, is abnormal highly expressed in multiple types of tumors and further affects the occurrence and development, but the potential correlations between SMYD2 expression and cervical cancer progression is still unclear. METHODS: We first used the bioinformatics website to screen the data of cervical cancer in (The Cancer Genome Atlas) TCGA and survival analysis was used to find the different survival rates in the SMYD2 high expression group and low expression group. Through immunohistochemistry, the association between SMYD2 expression and clinical-pathological features of cervical cancer patients was further evaluated. Quantitative PCR and Immunoblot were applied to investigate the relative mRNA and protein expression levels, respectively. In vivo and in vitro experiments were performed to explore the function of SMYD2 in cancer progression. RESULTS: We first found a high expression of SMYD2 in cervical cancer, and survival analysis found that the poorer survival rate in the SMYD2 high expression group than that in the low expression group. Herein, our study demonstrated that the expression of SMYD2 in patients with cervical cancer was associated with FIGO stage, tumor size and further correlated with poor prognosis. Our data further showed that the inhibition of SMYD2 expression in cervical cancer cell line Caski and Siha could dramatically block the proliferation of cervical cancer cells. Additionally, SMYD2-shRNA lentivirus infected remarkably inhibited tumorigenesis in mice compared with the scramble group. CONCLUSIONS: Taken together, this study provides strong evidence of the involvement of SMYD2 in cervical cancer growth and indicates that it could have high potential as a therapeutic target of cervical cancer.

13.
Dis Markers ; 2019: 5380197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30944666

RESUMO

Cervical cancer is one of the most common malignant neoplasms in gynecology. Protein tyrosine kinase 7 (PTK7) with an inactive kinase domain is an important regulator of multiple Wnt pathways under normal and various pathological conditions and overexpressed in various tumors; however, the clinical and biological significance of PTK7 in cervical cancer is still unknown. In the present study, the protein expression level of PTK7 was detected in clinical cervical cancer patient samples, and the relationship between PTK7 expression and clinicopathological features was analyzed. In addition, the Kaplan-Meier method was performed to estimate the overall survival (OS) and progression-free survival (PFS) of patients to investigate the clinicopathological significance of PTK7 expression. Functional assays demonstrated that knocking down PTK7 might inhibit the ability of cancer cells to proliferate and invade or migrate, both in vivo and in vitro. Thus, PTK7 might serve as a potential target for cervical cancer.


Assuntos
Biomarcadores Tumorais/genética , Moléculas de Adesão Celular/genética , Receptores Proteína Tirosina Quinases/genética , Neoplasias do Colo do Útero/genética , Animais , Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Humanos , Camundongos , Receptores Proteína Tirosina Quinases/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
14.
Int J Cardiol ; 280: 152-159, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30679074

RESUMO

BACKGROUND: Myocardial infarction (MI) is a common cardiovascular disease caused by myocardial ischemia. Also, microRNA (miRNA) participates in the pathophysiology of many cardiovascular diseases, which can affect stem cell transplantation in the treatment of MI. In this study, our aim is to explore effect of miR-26b on inflammatory response and myocardial remodeling through the MAPK pathway by targeting PTGS2 in mice with MI. METHODS: Microarray data analysis was conducted to screen MI-related differentially expressed gens (DEGs). Relationship between miR-26b and PTGS2 was testified. Cardiac function, inflammatory reaction, infarct size, and myocardial fibrosis were observed. The miR-26b expression and mRNA and protein levels of, PTGS2, ERK, JNK and p38 and Bcl-2/Bax were examined. The effect of miR-26b on cell apoptosis was also analyzed. RESULTS: MiR-26b was predicted to target PTGS2 further to mediate the MAPK pathway, thus affecting MI. MiR-26b negatively targeted PTGS2. MI mice showed decreased cardiac function, as well as increased inflammatory reaction, myocardial injury, area of fibrosis and myocardial cell apoptosis. After injection of miR-26b agomir or NS-398 (PTGS2 inhibitor), inflammatory response of MI mice was attenuated and myocardial remodeling induced by MI was alleviated. CONCLUSION: These findings indicate that miR-26b inhibits PTGS2 to activate the MAPK pathway, so as to reduce inflammatory response and improve myocardial remodeling in mice with MI.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Mediadores da Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Remodelação Ventricular/fisiologia , Animais , Mediadores da Inflamação/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/administração & dosagem , Infarto do Miocárdio/prevenção & controle , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Remodelação Ventricular/efeitos dos fármacos
15.
J Cell Physiol ; 234(7): 11722-11733, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30536946

RESUMO

Cardiac rupture and ventricular remodeling are recognized as the severe complications and major risk factors of acute myocardial infarction (AMI). This study aims to evaluate the regulatory roles of interleukin-1 receptor-associated kinase 3 (IRAK3) and nuclear factor-κB (NF-κB) signaling pathway in cardiac rupture and ventricular remodeling. Microarray analysis was performed to screen AMI-related differentially expressed genes and IRAK3 was identified. The models of AMI were established in male C57BL/6 mice to investigate the functional role of IRAK3. Afterwards, lentivirus recombinant plasmid si-IRAK3 was constructed for IRAK3 silencing. Next, cardiac function parameters were measured in response to IRAK3 silencing. The regulatory effects that IRAK3 had on myocardial infarct size and the content of myocardial interstitial collagen were analyzed. The regulation of IRAK3 silencing on the NF-κB signaling pathway was further assayed. The obtained results indicated that highly expressed IRAK3 and activated NF-κB signaling pathway were observed in myocardial tissues of mouse models of AMI, accompanied by increased expression of matrix metalloproteinase (MMP)-2/9 and tissue inhibitor of metalloproteinase 2 (TIMP-2). Notably, IRAK3 gene silencing inhibited the activation of NF-κB signaling pathway. Furthermore, IRAK3 gene silencing led to the decreased thickness of infarct area and collagen content of myocardial interstitium, alleviated diastolic, and systolic dysfunctions, as well as, facilitated cardiac functions in mice with AMI, corresponding to decreased expression of MMP-2/9 expression and increased expression of TIMP-2. Taken together, silencing of IRAK3 inactivates the NF-κB signaling pathway, and thereby impeding the cardiac rupture and ventricular remodeling, which eventually prevents AMI progression.


Assuntos
Inativação Gênica , Ruptura Cardíaca/prevenção & controle , Ruptura Cardíaca/fisiopatologia , Quinases Associadas a Receptores de Interleucina-1/genética , Infarto do Miocárdio/fisiopatologia , NF-kappa B/metabolismo , Transdução de Sinais , Remodelação Ventricular , Animais , Colágeno/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Ruptura Cardíaca/genética , Masculino , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/complicações , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Remodelação Ventricular/genética
16.
Sci Rep ; 7(1): 6596, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747764

RESUMO

High-carbon martensite steels (with C > 0.5 wt.%) are very hard but at the same time as brittle as glass in as-quenched or low-temperature-tempered state. Such extreme brittleness, originating from a twin microstructure, has rendered these steels almost useless in martensite state. Therefore, for more than a century it has been a common knowledge that high-carbon martensitic steels are intrinsically brittle and thus are not expected to find any application in harsh loading conditions. Here we report that these brittle steels can be transformed into super-strong ones exhibiting a combination of ultrahigh strength and significant toughness, through a simple grain-refinement treatment, which refines the grain size to ~4 µm. As a result, an ultra-high tensile strength of 2.4~2.6 GPa, a significant elongation of 4~10% and a good fracture toughness (K1C) of 23.5~29.6 MPa m1/2 were obtained in high-carbon martensitic steels with 0.61-0.65 wt.% C. These properties are comparable with those of "the king of super-high-strength steels"-maraging steels, but achieved at merely 1/30~1/50 of the price. The drastic enhancement in mechanical properties is found to arise from a transition from the conventional twin microstructure to a dislocation one by grain refinement. Our finding may provide a new route to manufacturing super-strong steels in a simple and economic way.

17.
Zhonghua Nan Ke Xue ; 20(5): 439-41, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-24908736

RESUMO

OBJECTIVE: To compare the advantages and disadvantages of the Foley catheter draining method versus the urethral stent plus gastric tube draining method for urine drainage following urethroplasty for hypospadias. METHODS: We retrospectively analyzed the clinical data of 361 cases of hypospadias treated by urethroplasty. After operation, 91 of the cases received urine drainage with the Foley catheter (group A) and 270 with a urethral stent plus a gastric tube (group B). We compared the incidence rates of bladder irritation, fistula, urethral stricture, and urethral diverticulum between the two groups of patients. RESULTS: No statistically significant differences were found between groups A and B in the incidences of bladder irritation (9.89% vs 10.70%, P > 0.05) and urethral diverticulum (1.09% vs 2.22%, P > 0.05). The incidence rate of fistula was markedly higher in group A than in B (20.80% vs 13.30%, P < 0.05), and so was that of urethral stricture (10.90% vs 5.55%, P < 0.05). CONCLUSION: The urethral stent plus gastric tube draining method is more effective than the Foley catheter draining method for urine drainage following urethroplasty.


Assuntos
Drenagem/métodos , Hipospadia/cirurgia , Stents , Uretra/cirurgia , Cateterismo Urinário/métodos , Idoso , Criança , Divertículo/etiologia , Humanos , Incidência , Masculino , Estudos Retrospectivos , Estreitamento Uretral/etiologia , Cateterismo Urinário/instrumentação
19.
Zhonghua Yi Xue Za Zhi ; 93(32): 2545-8, 2013 Aug 27.
Artigo em Chinês | MEDLINE | ID: mdl-24351593

RESUMO

OBJECTIVE: To explore the value of on-pump beating-heart coronary artery bypass grafting (OnP-BH CABG) for left-main patients with coronary heart disease through a comparative study with conventional coronary artery bypass grafting (CCABG). METHODS: The clinical data were retrospectively analyzed for 66 patients of OnP-BH and 48 control cases undergoing CCABG from January 2009 to January 2012 at Department of Cardiac Surgery, People's Hospital of Zhengzhou University. RESULTS: OnP-BH group had a better clinical outcome than CCABG group. There were obvious statistical difference in cardiopulmonary bypass (CPB) time, mean ventilation time, intensive care unit stay and recovery time of plasma cardiac troponin I (OnP-BH group vs CCABG group:(89 ± 25) vs (117 ± 28) min, (15 ± 14) vs (27 ± 19) h, (57 ± 27) vs (79 ± 34) h, (6.2 ± 1.8) vs (7.0 ± 2.4) d, all P < 0.05). The data of preoperative cTnI showed no significant difference between two groups (P > 0.05) .However, after CPB, significant intergroup difference existed in the level of cTnI (µg/L) OnP-BH group vs CCABG group: (0.5 h after CPB: (0.132 ± 0.022) vs (0.265 ± 0.014) , 1 h after CPB: (0.341 ± 0.027) vs (0.572 ± 0.046) , 1 h after operation: (0.641 ± 0.036) vs (0.932 ± 0.047) , 6 h after operation: (1.212 ± 0.765) vs (1.627 ± 0.542) and 24 h after operation: (1.496 ± 0.263) vs (1.734 ± 0.328) , all P < 0.05). CONCLUSIONS: On-pump beating-heart coronary artery bypass grafting is a feasible surgical approach for left-main patients. And it has a low risk and causes less myocardial damage.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Zhonghua Fu Chan Ke Za Zhi ; 45(1): 45-50, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20367926

RESUMO

OBJECTIVE: To study the therapeutic effect of recombinant adeno-associated virus carrying human endostatin gene therapy on endometriosis in mice model. METHODS: Recombinant adeno-associated virus vector carrying human endostatin gene and enhanced green fluorescent proteins gene (rAAV2-endostatin-EGFP) was constructed. Endometrium was from 12 patients with leiomyoma undergoing hysterectomy in Second Hospital, Tianjin Medical University between November and December 2008. Endometriosis models of nude mice were established by transplanting human endometrial fragments intooperitoneal surface. After 1 week, those 60 mice were divided into 3 groups: treatment group including 20 mice injected with rAAV2-endostatin-EGFP to ectopic lesion, control group including 20 mice injected with rAAV2-EGFP to ectopic lesion and blank control group including 20 mice injected with phosphate buffered saline (PBS) to the ectopic lesion. At 1, 2 and 3 weeks after treatment, those mice underwent laparotomy to observe the location and size of ectopic lesion in abdominal cavity. The expression of endostain protein, number of gland, microvessel density (MVD) and vascular endothelial growth factor (VEGF) were measured in ectopic lesions. The serum level of estradiol and progesterone were detected in nude mice among every groups. RESULTS: (1) All endometriosis of nude mice models were established successfully through peritoneum transplanting. After 1 week's treatment, flat lesion nodes, decreased gland number and narrow and atrophy glandular cavity were observed by light microscope. (2) The endostatin gene was transferred into nude mice successfully and expressed effectively. It was observed that endostatin protein expression was shown with enhanced green fluorescent proteins in ectopic lesion. (3) Glands number of ectopic lesion in rAAV2-endostatin-EGFP group (7.8 ± 1.9, 7.0 ± 1.5 and 5.5 ± 1.7) were significantly less than 10.1 ± 1.7, 10.2 ± 2.0 and 9.8 ± 2.4 in rAAV2-EGFP control group and 10.2 ± 2.2, 10.0 ± 2.0 and 9.7 ± 2.2 in PBS control group at 1, 2 and 3 weeks after treatment (all P < 0.05). Glands number of ectopic lesion in rAAV2-endostatin-EGFP group at 3 weeks was significantly less than those at 1 and 2 weeks after treatment (P < 0.05). (4) MVD of ectopic lesion in rAAV2-endostatin-EGFP group (12.2 ± 1.5, 11.4 ± 2.1 and 9.0 ± 1.4) was significantly less than those at rAAV2-EGFP control group (16.5 ± 1.7, 16.5 ± 1.9 and 16.9 ± 1.9) and PBS control group (16.2 ± 1.6, 16.0 ± 1.6 and 16.3 ± 1.7) at 1, 2 and 3 weeks after treatment (all P < 0.05). MVD of ectopic lesion in rAAV2-endostatin-EGFP group at 3 weeks was significantly less than those at 1 and 2 weeks after treatment (P < 0.05). (5) The rate and density of VEGF expression at ectopic lesion in rAAV2-endostatin-EGFP group (35%, 30%, 25% and 1.60 ± 0.43, 1.33 ± 0.30, 1.03 ± 0.36) were significantly less than those at rAAV2-EGFP control group (80%, 75%, 85% and 2.43 ± 0.53, 2.43 ± 0.29, 2.66 ± 0.45) and PBS control group (85%, 90%, 90% and 2.36 ± 0.53, 2.64 ± 0.57, 2.53 ± 0.52) at one 1, 2 and 3 weeks after treatment (all P < 0.05). The expression of VEGF at ectopic lesion in rAAV2-endostatin-EGFP group at 3 weeks was significantly less than those at 1 and 2 weeks after treatment (P < 0.05). (6) The level of estradial and progesterone in serum of nude mice of rAAV2-endostatin-EGFP group [E(2): (48 ± 7) pmol/L, P: (61 ± 8) nmol/L] did not reach statistical difference when compared with those at rAAV2-EGFP control group [E(2): (50 ± 9) pmol/L, P: (60 ± 10) nmol/L] and PBS control group [E(2): (48 ± 7) pmol/L, P: (58 ± 10) nmol/L, P > 0.05]. CONCLUSIONS: The recombinant adeno-associated virus carrying human endostatin gene therapy could inhibit angiogenesis at endometriotic lesions and not influence steroid level. The antiangiogenic gene therapy might become a novel option for endometriosis.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Endometriose/terapia , Endostatinas/genética , Terapia Genética/métodos , Inibidores da Angiogênese/genética , Animais , Dependovirus/genética , Modelos Animais de Doenças , Endometriose/genética , Endometriose/metabolismo , Endostatinas/metabolismo , Endostatinas/uso terapêutico , Feminino , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica , Proteínas Recombinantes/uso terapêutico , Recombinação Genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
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