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Laparoscopic cholecystectomy (LC) is one of the first laparoscopic procedures performed by surgical trainees. This study aims to determine preoperative and/or intraoperative predictors of difficult LC and to compare complications of LC performed by trainees with that performed by trained surgeons. A cohort of 180 consecutive patients with cholelithiasis who underwent LC was analyzed. We used univariate and binary logistic regression analyses to predict factors associated with difficult LC. We compared the rate of complications of LCs performed by trainees and that performed by trained surgeons using Pearson's chi-square test. Patients with impacted stone in the neck of the gallbladder (GB) (OR, 5.0; 95% CI, 1.59-15.77), with adhesions in the Triangle of Calot (OR, 2.9; 95% CI, 1.27-6.83), or with GB rupture (OR, 3.4; 95% CI, 1.02-11.41) were more likely to experience difficult LC. There was no difference between trainees and trained surgeons in the rate of cystic artery injury (p = .144) or GB rupture (p = .097). However, operative time of LCs performed by trained surgeons was significantly shorter (median, 45 min; IQR, 30-70 min) compared with the surgical trainees' operative time (60 min; IQR, 50-90 min). Surgical trainees can perform difficult LC safely under supervision with no increase in complications albeit with mild increase in operative time.
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AIM OF THE STUDY: Adenovector encoding tissue plasminogen activator (tPA) was shown to reduce experimental peritoneal adhesion. We investigated the targeting potential of our modified adenovector, its ability to reduce adhesions and the epigenetic role of histone methyltransferase EZH2 in adhesion formation. MATERIALS AND METHODS: Control lacZ, nonmodified tPA or modified tPA vectors were instilled in the peritoneal cavity after injury in de novo adhesions or after lysis of adhesions in recurrent adhesions. Adhesion severity was scored and adhesions and liver tissues were examined for adenovirus E4 gene and tPA mRNA expression. Levels of tPA, plasminogen activator inhibitor-1 (PAI-1), transforming growth factor-ß1 (TGF-ß1), and EZH2 expression were measured. RESULTS: E4 transcripts were detected in adhesions of nonmodified and modified and in livers of nonmodified but not in livers of modified de novo adhesions. Both nonmodified (p = 0.021) and modified vectors (p = 0.036) reduced the severity of de novo adhesions compared to lacZ vector. Levels of tPA in nonmodified (p = 0.021) and modified adhesions (p = 0.001) were elevated while PAI-1 (p = 0.013 and p = 0.001, respectively) and TGF-ß1 levels (p = 0.002 and p = 0.016, respectively) were reduced compared with lacZ group. All vectors were not expressed in recurrent adhesions and severity score were not different among groups. EZH2 levels were elevated in de novo nontreated (p = 0.001) and was further increased in recurrent (p = 0.001) nontreated adhesions compared with noninjured peritoneum. CONCLUSION: Modified adenovirus successfully targeted de novo adhesions but not liver tissues and reduced the severity of de novo adhesions. EZH2 is involved in the development and progression of peritoneal adhesions.
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Adenoviridae/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Vectores Genéticos/efectos adversos , Hígado/patología , Enfermedades Peritoneales/metabolismo , Enfermedades Peritoneales/patología , Complicaciones Posoperatorias/metabolismo , Proteínas E4 de Adenovirus/metabolismo , Animales , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Modelos Animales de Enfermedad , Proteína Potenciadora del Homólogo Zeste 2/genética , Epigénesis Genética , Vectores Genéticos/administración & dosificación , Humanos , Instilación de Medicamentos , Masculino , Enfermedades Peritoneales/etiología , Inhibidor 1 de Activador Plasminogénico/metabolismo , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/patología , Ratas , Ratas Wistar , Adherencias Tisulares/etiología , Adherencias Tisulares/metabolismo , Adherencias Tisulares/patología , Activador de Tejido Plasminógeno/genética , Activador de Tejido Plasminógeno/metabolismo , Transfección/instrumentación , Transfección/métodos , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
Liver fibrosis continues to be a major health problem worldwide due to lack of effective therapy. If the etiology cannot be eliminated, liver fibrosis progresses to cirrhosis and eventually to liver failure or malignancy; both are associated with a fatal outcome. Liver transplantation, the only curative therapy, is still mostly unavailable. Liver fibrosis was shown to be a reversible process; however, complete reversibility remains debatable. Recently, the molecular markers of liver fibrosis were shown to be transmitted across generations. Epigenetic mechanisms including DNA methylation, histone posttranslational modifications and noncoding RNA have emerged as major determinants of gene expression during liver fibrogenesis and carcinogenesis. Furthermore, epigenetic mechanisms have been shown to be transmitted through mitosis and meiosis to daughter cells and subsequent generations. However, the exact epigenetic regulation of complete liver fibrosis resolution and inheritance has not been fully elucidated. This communication will highlight the recent advances in the search for delineating the mechanisms governing resolution of liver fibrosis and the potential for multigenerational and transgenerational transmission of fibrosis markers. The fact that epigenetic changes, unlike genetic mutations, are reversible and can be modulated pharmacologically underscores the unique opportunity to develop effective therapy to completely reverse liver fibrosis, to prevent the development of malignancy and to regulate heritability of fibrosis phenotype.
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Investigación Biomédica , Epigénesis Genética , Cirrosis Hepática/genética , Cirrosis Hepática/terapia , Animales , Metilación de ADN , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Herencia , Histonas/metabolismo , Humanos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/metabolismo , Linaje , Fenotipo , Pronóstico , Procesamiento Proteico-Postraduccional , ARN no Traducido/genética , ARN no Traducido/metabolismo , Factores de RiesgoRESUMEN
Varicose veins affect approximately one-third of the adult population and result in significant psychological, physical, and financial burden. Nevertheless, the molecular pathogenesis of varicose vein formation remains unidentified. Venous hypertension exerted on veins of the lower extremity is considered the principal factor in varicose vein formation. The role of mechanotransduction of the high venous pressure in the pathogenesis of varicose vein formation has not been adequately investigated despite a good progress in understanding the mechanomolecular mechanisms involved in transduction of high blood pressure in the arterial wall. Understanding the nature of the mechanical forces, the mechanosensors and mechanotransducers in the vein wall, and the downstream signaling pathways will provide new molecular targets for the prevention and treatment of varicose veins. This paper summarized the current understanding of mechano-molecular pathways involved in transduction of hemodynamic forces induced by blood pressure and tries to relate this information to setting of venous hypertension in varicose veins.
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Adhesions are the most frequent complication of abdominopelvic surgery, yet the extent of the problem, and its serious consequences, has not been adequately recognized. Adhesions evolved as a life-saving mechanism to limit the spread of intraperitoneal inflammatory conditions. Three different pathophysiological mechanisms can independently trigger adhesion formation. Mesothelial cell injury and loss during operations, tissue hypoxia and inflammation each promotes adhesion formation separately, and potentiate the effect of each other. Studies have repeatedly demonstrated that interruption of a single pathway does not completely prevent adhesion formation. This review summarizes the pathogenesis of adhesion formation and the results of single gene therapy interventions. It explores the promising role of combinatorial gene therapy and vector modifications for the prevention of adhesion formation in order to stimulate new ideas and encourage rapid advancements in this field.
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Terapia Genética/métodos , Enfermedades Peritoneales/patología , Enfermedades Peritoneales/prevención & control , Peritoneo/patología , Adherencias Tisulares/patología , Adherencias Tisulares/prevención & control , Vectores Genéticos , Humanos , Hipoxia/complicaciones , Inflamación/complicaciones , Enfermedades Peritoneales/etiología , Complicaciones Posoperatorias/patología , Complicaciones Posoperatorias/prevención & control , Adherencias Tisulares/etiología , Factor de Crecimiento Transformador beta1/metabolismo , Cicatrización de Heridas/fisiologíaRESUMEN
The liver is an exceptional organ, not only because of its unique anatomical and physiological characteristics, but also because of its unlimited regenerative capacity. Unfolding of the molecular mechanisms that govern liver regeneration has allowed researchers to exploit them to augment liver regeneration. Dramatic progress in the field, however, was made by the introduction of the powerful tool of gene therapy. Transfer of genetic materials, such as hepatocyte growth factor, using both viral and non-viral vectors has proved to be successful in augmenting liver regeneration in various animal models. For future clinical studies, ongoing research aims at eliminating toxicity of viral vectors and increasing transduction efficiency of non-viral vectors, which are the main drawbacks of these systems. Another goal of current research is to develop gene therapy that targets specific liver cells using receptors that are unique to and highly expressed by different liver cell types. The outcome of such investigations will, undoubtedly, pave the way for future successful clinical trials.
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Ensayos Clínicos como Asunto , Terapia Genética , Regeneración Hepática , Animales , Ciclo Celular , Técnicas de Transferencia de Gen , Vectores Genéticos , Hepatocitos/citología , Hepatocitos/fisiología , Humanos , Hepatopatías/fisiopatología , Hepatopatías/terapiaRESUMEN
BACKGROUND: Tissue-plasminogen activator (tPA) demonstrated beneficial effects on peritoneal adhesion formation; however, its short half-life limits its continual fibrinolytic effect. Therefore, we delivered adenovirus encoding tPA to prevent adhesions. METHODS: Rats were subjected to peritoneal injury and assigned to two protocols. In de novo adhesion protocol, adenovirus encoding human tPA gene (Ad-htPA) was instilled after peritoneal injury in group 1 (n = 22), whereas group 2 received phosphate-buffered saline (PBS) (n = 24). In recurrent adhesion protocol, group 1 (n = 15) received the same Ad-htPA dose after adhesiolysis and group 2 (n = 13) received PBS. Adhesion severity was scored 1 week after ad-htPA instillation. Adhesions were analyzed for htPA mRNA by reverse transcription-polymerase chain reaction and levels of htPA, and fibrinolytic inhibitors PAI-1, TIMP-1, and TGF-beta1 were measured using enzyme-linked immunosorbent assay. RESULTS: htPA mRNA and protein were only expressed in adhesions from treated groups. A reduction in adhesion scores (P < .01) and in fibrinolytic inhibitors (P < .001) occurred in the treatment groups. Also, negative correlation was found (r = -.69, P < .01) between adhesion scores and htPA protein, but a positive correlation was found (r = .90, P < .01) between adhesion score and fibrinolytic inhibitors. No bleeding or wound complications were encountered. CONCLUSION: Administration of adenovector encoding htPA is safe and decreased de novo and recurrent peritoneal adhesions.
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Adenoviridae/genética , Enfermedades Peritoneales/metabolismo , Enfermedades Peritoneales/prevención & control , Adherencias Tisulares/metabolismo , Adherencias Tisulares/prevención & control , Activador de Tejido Plasminógeno/metabolismo , Animales , Modelos Animales de Enfermedad , Fibrinólisis/fisiología , Humanos , Inyecciones Intraperitoneales , Masculino , Ratas , Ratas Wistar , Índice de Severidad de la Enfermedad , Activador de Tejido Plasminógeno/administración & dosificación , Activador de Tejido Plasminógeno/genética , TransfecciónRESUMEN
BACKGROUND: Hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) gene transfer proved to enhance liver regeneration. However, elevation of their plasma levels may induce potentially serious distant effects such as tumorigenesis or proliferative retinopathy. AIMS: This study was performed to examine whether simultaneous administration of low-dose adenovirus encoding HGF and VEGF genes in dogs will stimulate liver proliferation but without inducing liver toxicity or systemic elevation of HGF and VEGF levels. METHODS: Adult dogs received an intravenous injection of low-dose adenoviral vectors encoding human HGF and VEGF (HGF/VEGF), beta-galactosidase (lacZ) or phosphate-buffered saline (PBS). Liver proliferation was measured using the proliferating cell nuclear antigen (PCNA) immunostaining labelling index. HGF and VEGF plasma concentrations and transaminases were repeatedly measured. Transgene expression was evaluated using reverse-transcription polymerase chain reaction. RESULTS: Human HGF and VEGF expressions were detected only in the liver of HGF/VEGF dogs at day 2 after injection but declined at sacrifice (day 7). No expression was detected in the liver of the lacZ or PBS groups. Plasma levels of HGF and VEGF were not statistically different from those in the lacZ group (P=0.81, P=0.22 respectively). The PCNA labelling index was five-fold higher in the HGF/VEGF group compared with the lacZ group (P<0.01). No immunostaining was detected in the PBS group. Transaminases were only elevated (P<0.01) in the lacZ group compared with the other groups. CONCLUSIONS: We showed that simultaneous administration of low-dose adenoviral vectors encoding human HGF and VEGF genes can induce transgene expression and liver proliferation without liver toxicity or systemic growth factor elevation.
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Adenoviridae/genética , Proliferación Celular , Terapia Genética/métodos , Vectores Genéticos , Factor de Crecimiento de Hepatocito/biosíntesis , Regeneración Hepática , Hígado/metabolismo , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Animales , Aspartato Aminotransferasas/sangre , Perros , Terapia Genética/efectos adversos , Factor de Crecimiento de Hepatocito/sangre , Factor de Crecimiento de Hepatocito/genética , Humanos , Inyecciones Intravenosas , Hígado/patología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Factores de Tiempo , Transducción Genética , Factor A de Crecimiento Endotelial Vascular/sangre , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
BACKGROUND: Restenosis due to intimal hyperplasia following percutaneous transluminal angioplasty limits its long-term efficacy. We evaluated the effect of colchicine on the development of intimal hyperplasia following balloon angioplasty and on the vascular endothelial growth factor (VEGF) expression in leukocytes. MATERIAL AND METHODS: Adult dogs underwent balloon angioplasty of the right iliofemoral artery. Group 1 served as control, while groups 2 and 3 (six animals per group) received 0.1 and 0.5 mg/kg/d of colchicine p.o., respectively, starting 2 d before angioplasty and continued for 14 d. Before angioplasty and at day 14, blood samples were collected for drug toxicity analysis and the determination of leukocyte expression of VEGF. Animals were euthanized and iliofemoral arteries were perfusion fixed in situ and processed for histological and morphometric analysis. RESULTS: Balloon angioplasty without colchicine resulted in 446% (P < 0.001), 111% (P = 0.7), and 267% (P < 0.001) increase in intimal and medial thickness and intima/media ratio compared with contralateral uninjured iliofemoral arteries. Low-dose and high-dose colchicine resulted in 32% and 58% reduction in intima/media ratio, respectively (both P < 0.001). VEGF expression in leukocytes of control group was up-regulated (40%), but was down-regulated by 12% and 55%, respectively, in low-dose and high-dose colchicine groups at 2 wk after angioplasty compared with preangioplasty expression. The results of complete blood count and serum transaminases and creatinine were within normal range. CONCLUSION: This study demonstrates that oral colchicine for 2 wk significantly reduces intimal hyperplasia following balloon angioplasty in dogs through down-regulation of leukocyte VEGF expression and without apparent toxicity.
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Fármacos Cardiovasculares/administración & dosificación , Colchicina/administración & dosificación , Hiperplasia/prevención & control , Leucocitos/efectos de los fármacos , Túnica Íntima/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Angioplastia de Balón , Animales , Modelos Animales de Enfermedad , Perros , Regulación hacia Abajo , Arteria Femoral , Expresión Génica , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
BACKGROUND: Homocysteine, vascular endothelial growth factor (VEGF), and endostatin have been implicated in angiogenesis and in the development and progression of atherothrombotic vascular disease. We sought to determine whether homocysteine modulates plasma levels of VEGF and endostatin and their expression in leukocytes in patients with peripheral arterial disease (PAD) or diabetes mellitus (DM). MATERIALS AND METHODS: Ten patients with PAD and 15 patients with type 2 DM were evaluated before and 6 wk after oral administration of folic acid and B vitamins. Evaluation included measurements of plasma levels of homocysteine, VEGF, and endostatin by enzyme-linked immunosorbent assay and the expression of VEGF and endostatin mRNAs in leukocytes using RT-PCR. The measurements were compared with baseline findings in 12 healthy subjects. RESULTS: Basal homocysteine (P < 0.001) and VEGF (P < 0.01) levels were elevated in all patients versus healthy subjects. Basal endostatin levels were lower in patients with PAD but were higher in patients with DM compared with healthy subjects (P < 0.001). In patients with PAD or DM, folic acid and B vitamins administration resulted in significant reduction (P < 0.001) of plasma levels of homocysteine (20.9% and 26.2%), VEGF (29.7% and 40.4%) and endostatin (9.4% and 5.7%), respectively. Moreover, VEGF and endostatin mRNA expression in leukocytes was down-regulated in all patients after B vitamins and folate treatment. CONCLUSION: These findings demonstrate that lowering of homocysteine with B vitamins and folic acid resulted in substantial reduction of plasma levels of VEGF but minimal reduction of endostatin and in down-regulation of their expression in leukocytes in patients with PAD or DM.
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Diabetes Mellitus/tratamiento farmacológico , Endostatinas/sangre , Homocisteína/sangre , Enfermedades Vasculares Periféricas/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/sangre , Complejo Vitamínico B/uso terapéutico , Adulto , Diabetes Mellitus/sangre , Regulación hacia Abajo , Endostatinas/biosíntesis , Femenino , Ácido Fólico/uso terapéutico , Expresión Génica , Humanos , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Neovascularización Patológica , Enfermedades Vasculares Periféricas/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tiamina/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/biosíntesisRESUMEN
OBJECTIVES: Both heme oxygenase-1 (HO-1) and vascular endothelial growth factor (VEGF) have been shown to be involved in the progression of atherosclerosis. The relationship between HO-1 and VEGF gene expression and their proteins in endothelial cells from human atherosclerotic arterial specimens was investigated. DESIGN AND METHODS: The study included seventeen human arterial specimens with early and six specimens with advanced atherosclerotic lesions. Ten specimens were obtained from healthy young adults undergoing arterial reconstruction for trauma and were considered as non-atherosclerotic control. HO-1 and VEGF expressions as well as HO activity and VEGF protein content were measured in isolated endothelial cells (ECs). RESULTS: HO-1 expression and activity (5.3+/-2.1 nmol bilirubin/mg protein/h) were only present in ECs from advanced atherosclerotic lesions. VEGF expression was more strongly expressed in ECs from advanced lesion compared with early lesions and was absent in healthy arteries. VEGF protein (1.35+/-0.69 ng/mg) was only detected in advanced lesions. A significant positive correlation (r=0.9, p<0.01) exists between HO activity and VEGF protein content in ECs of advanced lesions. CONCLUSIONS: This study demonstrated that HO-1 expression and activity in ECs are present only in advanced atherosclerosis whereas, VEGF expression is present in early as well as in advanced atherosclerosis and the degree of its expression increases with severity of atherosclerosis. This study suggests an association between HO activity and VEGF protein in human ECs from advanced atherosclerotic lesions.