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1.
Yi Chuan ; 46(6): 452-465, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38886149

RESUMO

LIN28A and its homolog LIN28B are highly conserved RNA-binding proteins that play important roles in early embryonic development, somatic cell reprogramming, metabolism and tumorigenesis. LIN28A/B are highly expressed in a variety of malignant tumors such as breast cancer. They play important roles in the initiation, maintenance, and metastasis of tumors and are associated with poor prognosis. Previous studies have shown that the main regulatory mechanisms of LIN28A/B include let-7s dependent ways and let-7s independent ways, such as directly targeting mRNA. In this review, we summarize the function and molecular regulatory mechanisms of LIN28A/B in malignant tumors such as liver cancer, breast cancer and colorectal cancer, in order to provide references for further exploring the function and mechanism of LIN28A/B and their possible roles in clinical applications.


Assuntos
Neoplasias , Proteínas de Ligação a RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Progressão da Doença , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética
2.
Ann Plast Surg ; 80(5): 572-580, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29443833

RESUMO

BACKGROUND: Wound healing is a complex process that relies on growth factors and stimulation of angiogenesis. Tissue engineering materials composed of adipose-derived stem cells (ADSCs) and silk fibroin (SF)/chitosan (CS) may be able to solve this problem. The aim of this study was to investigate the wound-healing potential of ADSC-seeded SF/CS in streptozotocin-induced diabetic rats. MATERIALS AND METHODS: Thirty-six male Sprague-Dawley rats were purchased and randomly assigned into 3 groups: a control group (no graft), a group treated with SF/CS film graft, and a group treated with ADSC-seeded SF/CS graft. The number of animals in each group was 12. Diabetes was induced by an intraperitoneal injection of streptozotocin. A cutaneous wound was incised at the dorsal region of all the experimental animals. The ADSCs were labeled with CM-Dil fluorescent staining. Wound healing was assessed for all animal groups by observing the rate of wound closure and hematoxylin and eosin staining. The expression of epidermal growth factor, transforming growth factor-ß, and vascular endothelial growth factor at the wound sites was studied by enzyme-linked immunosorbent assay to evaluate the effect of growth factors secreted by ADSCs. The differentiation of ADSCs was analyzed by immunofluorescence staining. RESULTS: The ADSC-seeded SF/CS film treatment significantly increased the rates of wound closure in treated animals, and hence wound healing was drastically enhanced for ADSC-SF/CS treatment groups compared with control groups and SF/CS film treatment group. Histological observations showed the condition of wound healing. Enzyme-linked immunosorbent assay and immunofluorescence staining observations showed the secretion and differentiation of ADSCs, respectively. CONCLUSIONS: Our analyses clearly suggested that it is feasible and effective to enhance wound healing in a diabetic rat model with ADSC-seeded SF/CS film.


Assuntos
Adipócitos , Quitosana , Diabetes Mellitus Experimental , Fibroínas , Células-Tronco , Cicatrização , Animais , Masculino , Ratos , Adipócitos/citologia , Técnicas de Cultura de Células , Quitosana/farmacologia , Ensaio de Imunoadsorção Enzimática , Fator de Crescimento Epidérmico/metabolismo , Fibroínas/farmacologia , Citometria de Fluxo , Imunofenotipagem , Distribuição Aleatória , Ratos Sprague-Dawley , Células-Tronco/citologia , Fator de Crescimento Transformador beta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos dos fármacos
3.
J Plast Surg Hand Surg ; 55(4): 210-215, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33530846

RESUMO

Cesarean section results in scarring, which usually leads to adhesion between the subcutaneous fat and the abdominal wall muscle. The present study aimed to evaluate the therapeutic effect of autologous fat grafting on scar adhesion to the abdominal wall after cesarean section. Thirty-six patients with scar adhesion to the abdominal wall after cesarean section were recruited and treated between October 2013 and December 2015. The adhesion between the subcutaneous fat and the abdominal wall muscle was carefully separated through a small incision in the original scar to form multiple subcutaneous tunnels. Aspirated fat was injected into the scar lesion and subcutaneous tunnels, and the wound was then sutured. The clinical outcome was evaluated by comparing the pretreatment and 1-year posttreatment photographs and Patient and Observer Scar Assessment Scale (POSAS) scores. All patients had a marked improvement in the appearance, texture, and depression of the scar during 12 months of follow-up. The 1-year posttreatment POSAS scores for the color, pain, pruritus, hardness, fullness, mobility, and appearance of the scar were significantly decreased compared with the pretreatment scores. Hematoxylin-eosin staining revealed adipocyte-like cells in treated scar tissue specimens obtained 1 year after treatment. None of the patients reported severe adverse reactions. Autologous fat grafting combined with adhesion release may be a good treatment option for abdominal wall scarring after cesarean section. This method is minimally invasive and effective in achieving good functional and esthetic outcomes.


Assuntos
Parede Abdominal , Cicatriz , Parede Abdominal/cirurgia , Cesárea/efeitos adversos , Cicatriz/etiologia , Cicatriz/patologia , Cicatriz/cirurgia , Feminino , Humanos , Gravidez , Aderências Teciduais/etiologia , Aderências Teciduais/cirurgia , Transplante Autólogo
4.
Transfusion ; 50(4): 801-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20003049

RESUMO

BACKGROUND: Direct thrombin inhibitors (DTIs) provide an alternative method of anticoagulation for patients with a history of heparin-induced thrombocytopenia (HIT) or HIT with thrombosis (HITT) undergoing cardiopulmonary bypass (CPB). In the following report, a 65-year-old critically ill patient with a suspected history of HITT was administered argatroban for anticoagulation on bypass during heart transplantation. The patient required massive transfusion support (55 units of red blood cells, 42 units of fresh-frozen plasma, 40 units of cryoprecipitate, 40 units of platelets, and three doses of recombinant Factor VIIa) for severe intraoperative and postoperative bleeding. STUDY DESIGN AND METHODS: Plasma samples from before and after CPB were analyzed postoperatively for argatroban concentration using a modified ecarin clotting time (ECT) assay. RESULTS: Unexpectedly high concentrations of argatroban were measured in these samples (range, 0-32 microg/mL), and a prolonged plasma argatroban half life (t(1/2)) of 514 minutes was observed (published elimination t(1/2) is 39-51 minutes [< or = 181 minutes with hepatic impairment]). CONCLUSIONS: Correlation of plasma argatroban concentration versus the patient's coagulation variables and clinical course suggest that prolonged elevated levels of plasma argatroban may have contributed to the patient's extended coagulopathy. Because DTIs do not have reversal agents, surgical teams and transfusion services should remain aware of the possibility of massive transfusion events during anticoagulation with these agents. This is the first report to measure plasma argatroban concentration in the context of CPB and extended coagulopathy.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Transplante de Coração/efeitos adversos , Heparina/efeitos adversos , Ácidos Pipecólicos/sangue , Inibidores da Agregação Plaquetária/sangue , Trombocitopenia/induzido quimicamente , Trombose/induzido quimicamente , Idoso , Arginina/análogos & derivados , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/induzido quimicamente , Criança , Humanos , Infusões Intravenosas , Ácidos Pipecólicos/efeitos adversos , Ácidos Pipecólicos/uso terapêutico , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Sulfonamidas
5.
Biochem J ; 397(3): 399-406, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16669789

RESUMO

Human and mouse telomerases show a high degree of similarity in both the protein and RNA components. Human telomerase is more active and more processive than the mouse telomerase. There are two key differences between hTR [human TR (telomerase RNA)] and mTR (mouse TR) structures. First, the mouse telomerase contains only 2 nt upstream of its template region, whereas the human telomerase contains 45 nt. Secondly, the template region of human telomerase contains a 5-nt alignment domain, whereas that of mouse has only 2 nt. We hypothesize that these differences are responsible for the differential telomerase activities. Mutations were made in both the hTR and mTR, changing the template length and the length of the RNA upstream of the template, and telomerase was reconstituted in vitro using mouse telomerase reverse transcriptase generated by in vitro translation. We show that the sequences upstream of the template region, with a potential to form a double-stranded helix (the P1 helix) as in hTR, increase telomerase activity. The longer alignment domain increases telomerase activity only in the context of the P1 helix. Thus the TR contributes to regulating the level of activity of mammalian telomerases.


Assuntos
RNA/genética , Telomerase/metabolismo , Animais , Extratos Celulares , Linhagem Celular Tumoral , Humanos , Camundongos , Mutação , Estrutura Secundária de Proteína , Telomerase/química , Telomerase/genética , Moldes Genéticos
6.
Kaohsiung J Med Sci ; 33(8): 379-384, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28811006

RESUMO

Autologous fat transplantation has been applied widely in clinic. However, the low survival rate is still a problem to be solved. Studies shows that the human adipose-derived stem cells (ADSCs) transfected by vascular endothelial growth factor (VEGF) can improve the survival rate of autologous fat transplantation. Our study is to evaluate the effects of the conditioned medium of VEGF-transfected human adipose-derived stem cells (VEGF-ADSCs-CM) on fat transplantation. ADSCs were isolated and transfected with MOI = 40. The study was divided into three groups, VEGF-ADSCs-CM group, normal-ADSCs-CM group and control group. The conditioned media for VEGF-ADSCs-CM group and normal-ADSCs-CM group were collected, and then mixed with fat, with the mixtures being injected into the back of nude mice. On 4, 7, 15, 30, 60 days after transplantation, the grafts were evaluated on the wet weight, histology, ELISA and western blot. As the results revealed, the survival rate of VEGF-ADSCs-CM group was highest with the best fat cell morphology, and the VEGF secretion of VEGF-ADSCs-CM group was also highest. Therefore, our study demonstrates that VEGF-ADSCs-CM can improve the survival rate of fat transplantation effectively, and VEGF-ADSCs-CM can be regarded as an effective assisted method for fat transplantation.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Sobrevivência de Enxerto , Transplante de Células-Tronco/métodos , Fator A de Crescimento do Endotélio Vascular/genética , Gordura Abdominal/citologia , Gordura Abdominal/imunologia , Gordura Abdominal/metabolismo , Gordura Abdominal/cirurgia , Adipócitos/citologia , Adipócitos/imunologia , Adipócitos/metabolismo , Animais , Diferenciação Celular , Feminino , Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Plasmídeos/química , Plasmídeos/metabolismo , Células-Tronco/citologia , Células-Tronco/imunologia , Células-Tronco/metabolismo , Transfecção , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/imunologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Clin Chim Acta ; 363(1-2): 165-76, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16154123

RESUMO

BACKGROUND: Traditionally, transfusion medicine, platelet and human leukocyte antigen (HLA) typing, and forensic medicine relied on serologic studies. METHODS: In recent years, molecular testing on nucleic acids has been increasingly applied to these areas. Although conventional molecular diagnostic methods such as PCR-sequence-specific priming, PCR-restriction fragment-length polymorphism, PCR-single-strand conformation polymorphism, sequence-based typing, and DNA fingerprinting have been shown to perform well, their use is limited by long turnaround times, high cost, labor-intensiveness, the need for special technical skills, and/or the high risk of amplicon contamination. With advance of fast and/or high-throughput methods and platforms that often combine amplification and detection, a new era of molecular genotyping is emerging in these fields dominated by serology for a century. As new targets, short tandem repeats, mitochondrial DNA and Y-chromosome sequences were introduced for forensic applications. This article reviews the current status of the application of rapid and/or high-throughput genotyping methods to these areas. RESULTS: The results are already promising with real-time PCR, pyrosequencing, microarrays, and mass spectrometry and show high concordance rates with classic serologic and earlier manual molecular diagnostic methods. Exploration of other emerging methodologies will likely further enhance the diagnostic utility of molecular testing in these areas.


Assuntos
Plaquetas/metabolismo , Eritrócitos/metabolismo , Medicina Legal/métodos , Antígenos HLA/metabolismo , Técnicas de Diagnóstico Molecular/métodos , Ácidos Nucleicos/sangue , Impressões Digitais de DNA/métodos , Genótipo , Antígenos HLA/genética , Humanos , Análise em Microsséries/métodos , Técnicas de Diagnóstico Molecular/tendências , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos
8.
Neural Regen Res ; 11(9): 1431-1437, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27857745

RESUMO

13-Methyltetradecanoic acid can stabilize cell membrane and have anti-inflammatory, antioxidant and anti-apoptotic effects. Previous studies mainly focused on peripheral nerve injury, but seldom on the central nervous system. We investigated whether these properties of 13-methyltetradecanoic acid have a neuroprotective effect on focal cerebral ischemia/reperfusion injury, and detected the expression of basic fibroblast growth factor and vascular endothelial growth factor. This study established rat models of middle cerebral artery occlusion/reperfusion injury by ischemia for 2 hours and reperfusion for 24 hours. At the beginning of reperfusion, 13-methyltetradecanoic acid 10, 40 or 80 mg/kg was injected into the tail vein. Results found that various doses of 13-methyltetradecanoic acid effectively reduced infarct volume, mitigate cerebral edema, and increased the mRNA and protein expression of basic fibroblast growth factor and vascular endothelial growth factor at 24 hours of reperfusion. The effect was most significant in the 13-methyltetradecanoic acid 40 and 80 mg/kg groups. The findings suggest that 13-methyltetradecanoic acid can relieve focal ischemia/reperfusion injury immediately after reperfusion, stimulate the upregulation of basic fibroblast growth factor and vascular endothelial growth factor to exert neuroprotective effects.

9.
J Inflamm (Lond) ; 12: 42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26180518

RESUMO

BACKGROUND: The tristetraprolin (TTP) family of mRNA-binding proteins contains three major members, Ttp, Zfp36l1, and Zfp36l2. Ttp down-regulates the stability of AU-rich element-containing mRNAs and functions as an anti-inflammation regulator. METHODS: To examine whether other TTP family proteins also play roles in the inflammatory response, their expression profiles and the possible mRNA targets were determined in the knockdown cells. RESULTS: Ttp mRNA and protein were highly induced by lipopolysaccharide (LPS), whereas Zfp36l1 and Zfp36l2 mRNAs were down-regulated and their proteins were phosphorylated during early lipopolysaccharide stimulation. Biochemical and functional analyses exhibited that the decrease of Zfp36l2 mRNA was cross-regulated by Ttp. Knockdown of Zfp36l1 and Zfp36l2 increased the basal level of Mkp-1 mRNAs by prolonging its half-life. Increasing the expression of Mkp-1 inhibited the activation of p38 MAPK under lipopolysaccharide stimulation and down-regulated Tnfα, and Ttp mRNA. In addition, hyper-phosphorylation of Zfp36l1 might stabilize Mkp-1 expression by forming a complex with the adapter protein 14-3-3 and decreasing the interaction with deadenylase Caf1a. CONCLUSIONS: Our findings imply that the expression and phosphorylation of Zfp36l1 and Zfp36l2 may modulate the basal level of Mkp-1 mRNA to control p38 MAPK activity during lipopolysaccharide stimulation, which would affect the inflammatory mediators production. Zfp36l1 and Zfp36l2 are important regulators of the innate immune response.

10.
Blood Rev ; 17(2): 111-22, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12642123

RESUMO

Even though the blood supply is very safe, the risk of transfusion transmitted disease is not zero. To improve the safety of the blood supply, pathogen reduction (PR) technology has been developed. The principle of most current PR strategies involves modifying DNA or RNA templates and making them inaccessible to DNA or RNA polymerase. Several platforms of pathogen reduction are available including psoralens, alkylating compounds, binary ethyleneimine-like compounds, riboflavin, methylene blue, and solvent-detergent treatment. PR systems have been designed for RBC, plasma, and platelets. PR technology has been found to be effective for a variety of pathogens including lipid-enveloped and non-enveloped viruses, bacteria and parasites. Pre-clinical studies and Phase III clinical trials to evaluate the efficacy and safety of these PR technologies are currently ongoing.


Assuntos
Bancos de Sangue/normas , Transfusão de Sangue/normas , Sangue/microbiologia , Animais , Antibacterianos , Anti-Infecciosos/uso terapêutico , Aziridinas/uso terapêutico , Infecções Bacterianas/sangue , Infecções Bacterianas/prevenção & controle , Infecções Bacterianas/transmissão , Sangue/efeitos dos fármacos , Transfusão de Sangue/métodos , Furocumarinas/uso terapêutico , Humanos , Riboflavina/uso terapêutico , Viroses/sangue , Viroses/prevenção & controle , Viroses/transmissão
11.
Artigo em Inglês | MEDLINE | ID: mdl-25220781

RESUMO

OBJECTIVE: The purpose of this study is to evaluate the biomechanics of short dental implants. STUDY DESIGN: Three-dimensional finite element analysis was used to simulate stress distribution of 8-mm implants with 6 different diameters in I to IV types of bone densities; meanwhile, axial and oblique loads were applied in this study. RESULTS: It was found that the maximum Von-Mises stress varied significantly when the diameter was within 3.3 mm and 5 mm, whereas the change of peak stress was not obvious when the diameter was within 5.5 mm to 7.1 mm. The peak stress on the implant-bone interface increased with the reduction of bone density. The stress in types I and II had similar distribution and the same was true for types III and IV. CONCLUSIONS: These results revealed that implants with larger diameter (<5.5 mm) and bone quality enhancement may be preferable to get better clinical effects. Prospective clinical studies are required to confirm this.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Análise do Estresse Dentário/métodos , Desenho Assistido por Computador , Planejamento de Prótese Dentária , Módulo de Elasticidade , Análise de Elementos Finitos , Humanos , Imageamento Tridimensional , Teste de Materiais , Osseointegração , Titânio , Tomografia Computadorizada por Raios X/métodos
12.
Int J Oral Sci ; 5(4): 212-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24008269

RESUMO

Cellular fibronectin (cFn) is a type of bioactive non-collagen glycoprotein regarded as the main substance used to maintain periodontal attachment. The content of cFn in some specific sites can reflect the progress of periodontitis or peri-implantitis. This study aims to evaluate the expression of cFn messenger RNA (mRNA) in tissues of adult periodontitis and peri-implantitis by real-time fluorescent quantitative polymerase chain reaction (PCR) and to determine its clinical significance. A total of 30 patients were divided into three groups of 10: healthy, adult periodontitis and peri-implantitis. Periodontal tissue biopsies (1 mm×1 mm×1 mm) from each patient were frozen in liquid nitrogen. Total RNA was extracted from these tissues, and the content, purity and integrity were detected. Specific primers were designed according to the sequence, and the mRNA expression levels of cellular fibronectin were detected by real-time PCR. The purity and integrity of the extracted total RNA were both high, and the specificity of amplified genes was very high with no other pollution. The mRNA expression of cFn in the adult periodontitis group (1.526±0.441) was lower than that in the healthy group (3.253±0.736). However, the mRNA expression of cFn in the peri-implantitis group (3.965±0.537) was significantly higher than that in the healthy group. The difference revealed that although both processes were destructive inflammatory reactions in the periodontium, the pathomechanisms were different and the variation started from the transcription level of the cFn gene.


Assuntos
Fibronectinas/análise , Peri-Implantite/metabolismo , Periodontite/metabolismo , RNA Mensageiro/análise , Adulto , Perda do Osso Alveolar/metabolismo , Feminino , Fibronectinas/genética , Gengiva/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/metabolismo , Índice Periodontal , Bolsa Periodontal/metabolismo , Periodonto/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transcrição Gênica/genética , Adulto Jovem
13.
Am J Clin Pathol ; 133(4): 533-42, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20231605

RESUMO

As the 100th anniversary of the Flexner report nears, medical student education is being reviewed at many levels. One area of concern, expressed in recent reports from some national health care organizations, is the adequacy of training in the discipline of laboratory medicine (also termed clinical pathology). The Academy of Clinical Laboratory Physicians and Scientists appointed an ad hoc committee to review this topic and to develop a suggested curriculum, which was subsequently forwarded to the entire membership for review. The proposed medical student laboratory medicine curriculum defines goals and objectives for training, provides guidelines for instructional methods, and gives examples of how outcomes can be assessed. This curriculum is presented as a potentially helpful outline for use by medical school faculty and curriculum committees.


Assuntos
Currículo/normas , Educação Médica/normas , Patologia Clínica/educação , Competência Clínica/normas , Técnicas de Laboratório Clínico , Humanos , Patologia Clínica/normas , Estudantes de Medicina
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